Journals >Spectroscopy and Spectral Analysis
Contents
2017
Volume: 37 Issue 4
61 Article(s)
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Resonance Spectra and Sensing Characteristics of Plasmons in Graphene-Covered Aluminum Nano-Grating
NONG Jin-peng, WEI Wei, ZHU Yong, TANG Lin-long, ZHANG Gui-wen, JIANG Xiao, CHEN Na, and WEI Da-peng
Combining with the extraordinary advantages of fast-speed, label-free, high sensitivity, and real-time results, surface plasmon resonance (SPR) technology has been widely used in fields such as biochemical analysis, environmental monitoring and food safety as well as in many other aspects. In contrast to the SPR sensorCombining with the extraordinary advantages of fast-speed, label-free, high sensitivity, and real-time results, surface plasmon resonance (SPR) technology has been widely used in fields such as biochemical analysis, environmental monitoring and food safety as well as in many other aspects. In contrast to the SPR sensors utilizing the traditional noble metals (gold, silver), SPR sensors based on aluminum plasmonic have recently drawn researchers interests in these fields due to its superior features of low cost, narrow spectral bandwidth and amenability to manufacturing processes. However, aluminum exhibits the intrinsic shortcomings of bad biocompatibility and easy oxidation, which severely limit its applications. To address this problem, a surface plasmon resonance sensor based on graphene-covered aluminum nano-grating is proposed. A monolayer graphene is employed as the sensing layer that can contact directly with the molecular to be measured, because it emerged as a revolutionary two-dimensional material that shows the attractive properties of good chemical stability, large surface volume ratio, strong anti-oxidation ability, and excellent biocompatibility. Firstly, a physical model of the sensor is built based on finite element method employing COMSOL multiphysics, and the influence of the graphene layers and structure parameters of aluminum nano-grating (occupation ratio, height, and period) on the resonance spectral characteristics is investigated. Simulation results show that the coating of the graphene on the aluminum nano-grating exhibits strongly enhanced interaction between incident light and the device. Moreover, the resonance spectrum possesses the narrowest bandwidth when the aluminum nano-grating is covered by a monolayer graphene, and the reflectance of resonance spectrum is zero when the structure parameters of nano-grating are Λ=600 nm, H=40 nm and η=70%, respectively. Secondly, we further investigate the sensing characteristic of the sensor with optimized structure parameters. The results demonstrate that the sensor with a monolayer graphene covered on aluminum nano-grating obtains the highest figure of merit of 24.5 RIU-1, and the corresponding sensitivity is 626 nm·RIU-1. Such a SPR sensor with high sensitivity and good biocompatibility provides a green platform for applications in fields such as biochemical analysis, environmental monitoring and food safety monitoring..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 997 (2017)
Development of Laboratory Microscopic X-Ray Fluorescence Spectrometer and the Study on Spatial Distribution of Elements in Biofilms and Maize Seeds
LUO Li-qiang, SHEN Ya-ting, MA Yan-hong, XU Tao, CHU Bin-bin, ZENG Yuan, and LIU Jian
Microscopic X-ray florescence spectrometry (μXRF) can be used to obtain the information on distribution and correlation of the chemical elements in the biogeochemical samples. The information is useful in revealing conditions of material formation, dynamic processes of elemental distribution and correlation among them,Microscopic X-ray florescence spectrometry (μXRF) can be used to obtain the information on distribution and correlation of the chemical elements in the biogeochemical samples. The information is useful in revealing conditions of material formation, dynamic processes of elemental distribution and correlation among them, as well as biological metabolism. A laboratory μXRF spectrometer was developed with combining a polycapillary microfocus X-ray beam excitation with a rhodium anode (50 kV, 1 mA), a silicon drift detector (SDD) and three-dimensional scanning capability. The angle between the sample stage and the SDD detector was designed to be adjustable so that an in situ determination of a heterotypic sample, such as geological samples, can be made with the μXRF set. A rock-biofilm sample was taken from a field investigation, where there is a small mine and the rock in a shallow pool was covered by a green biofilm. The rock-biofilm sample was stored in a refrigerator for further μXRF measurement. Maize seeds were from markets. Dry maize seeds and ones with Pb-soaked were sliced before the μXRF measurements. Then, the developed laboratory μXRF spectrometer was applied to study the mobilization of lead in the rock-biofilms, and location of K, Ca, Mn, Fe, Cu, Zn and Pb in germination of the maize seeds. We found that (1) Pb accumulated in biofilms with a bioaccumulation factor of 1.7. (2) Pb increased gradually from rock to biofilm, and then decreased from biofilm to air. A peak occurred in the biofilm. (3) In maize seeds without Pb-soaked, K, Ca, Mn, Fe, Cu, Zn and Pb were detectable. Zn was mainly found in endosperm, a small amount of Zn in embryo; trace Fe was detected in endosperm and embryo; Trace Pb was detectable in endosperm, not in embryo. (4) In germination of maize seeds soaked with dilute Pb solution, K was detected in both endosperm and embryo; Fe was distributed in seed coat and endosperm; Cu and Zn were in endosperm; most of Pb occurred in embryo and especially accumulated in fresh roots, which implies that the accumulation of Pb in roots functions as tolerance of detoxification of toxic elements in seed germination..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1003 (2017)
Chemical Compositions and Sources of Glaze-Making Technology of Bluish-White Glaze Fired at Fanchang Kiln, Anhui Province
YANG Yu-zhang, ZENG Ling-yuan, WANG Fa-zhi, CUI Wei, XU Fan, and ZHANG Ju-zhong
Fanchang kiln was one of the earliest Chinese bluish-white porcelain kilns which fired this special porcelain class as early as in Five Dynasties (AD 907-960). This paper aims to explore the characteristics and evolution of chemical compositions of bluish-white porcelain glaze in Fanchang kiln as well as the technologyFanchang kiln was one of the earliest Chinese bluish-white porcelain kilns which fired this special porcelain class as early as in Five Dynasties (AD 907-960). This paper aims to explore the characteristics and evolution of chemical compositions of bluish-white porcelain glaze in Fanchang kiln as well as the technology sources of early bluish-white glaze in Southern China. To determine the chemical compositions of bluish-white glaze from Five Dynasties to the middle Northern Song Dynasty at Fanchan kiln, Energy Dispersive X-ray Fluorescence Spectrometry (EDXRF) was used and the results were analyzed synthetically with the chemical compositions of white porcelain glaze of Ding kiln in northern China; and blue porcelain glaze of Yue kiln in southern China. The analytic results indicate that the chemical compositions of major, minor and trace elements in porcelain glazes changed greatly in the middle North Song Dynasty with the fall of SiO2 and the rise of CaO, but the oxide contents of coloring elements like Fe, Mn, Ti change slightly during this period. Color shift from whitish to green of bluish-white glaze might be related to the change of bodys color at Fanchang kiln. Meanwhile, the chemical composition of early bluish-white glaze represented by Fanchang kiln in south China is similar to Ding kiln in northern China. Its glazed formulation process may be derived from the white kiln represented by Ding kiln in northern China at the same period, and it has little relationship with the Yue kiln in southern China. The research results are of great significance to understand the chemical compositions characteristics of early bluish-white glaze in China as well as the exchange of porcelain making technology between the north and south China during the Late Tang Dynasty and Five Dynasties..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1009 (2017)
Pressure-Induced Phase Transition of NH4HSO4
LIU Shi, CUI Hai-ning, and ZHOU Mi
Due to the important applications of ferroelectric materials in the field of scientific research, the design and mechanism of functional ferroelectric materials have received great attention. The properties of materials cannot be separated from the study of structures. In order to understand the structure and phase behDue to the important applications of ferroelectric materials in the field of scientific research, the design and mechanism of functional ferroelectric materials have received great attention. The properties of materials cannot be separated from the study of structures. In order to understand the structure and phase behavior of a typical ferroelectric material-NH4HSO4, the in-situ high Pressure Raman measurement of NH4HSO4 up to 17 GPa is performed. With the increase of pressure, most of Raman bands shifted to higher wave number region. And the Intensities of two Raman bands (located at 1 018 and 3 183 cm-1) changed greatly with pressure, suggests that the electron density of sulfate and ammonium ion is redistributed. Based on the relationship between the frequency shift and pressure curves, it is found that there are two first-order phase transitions at about 6 GPa and 10.5 GPa, respectively. According to the changes tendency of SO stretching vibration band under compression, it is found that the hydrogen bond at different phases has the opposite change tendency. It provides a new strategy for investigation of AHSO4 ferroelectric materials under pressure..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1016 (2017)
Research Progress of Detection for Nanoparticles in Water
ZHAO Chun, ZHANG Xuan, SUN Zhi-hua, YANG Guang, ZHU Yun-hua, SI Bin, and ZHENG Huai-li
With the broad application of nanomaterials in cosmetics and other industries, the more and more nanoparticles have been released into the aquatic environment, which leads to a number of inevitable environmental issues. At the same time, they cause a negative effect on all kinds of organism including human being. HenceWith the broad application of nanomaterials in cosmetics and other industries, the more and more nanoparticles have been released into the aquatic environment, which leads to a number of inevitable environmental issues. At the same time, they cause a negative effect on all kinds of organism including human being. Hence, the enrichment and detection technologies of nanoparticles in water have attracted more and more attention. Currently, a variety of technologies can be used to detect the concentration of trace nanoparticles, but they all have certain limitations in sensitivity and accuracy. In this paper, the pretreatment techniques such as ultrafiltration, chromatography, solid phase extraction, and cloud point extraction of nanoparticles in aquatic environment are generalized. The common detection techniques of nanoparticles, such as spectrum technology, the inductively coupled with plasma mass spectrometry and electrochemical detection techniques are summarized. Moreover, the further development prospects of pretreatment and detection technologies of nanoparticles are also discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1021 (2017)
The Study of Additivity of Scattering Spectrum Based on BRDF Theory
SONG Wei, MIAO Xin-hui, SHI Jing, XIN Min-si, LI Long, MENG Ling-peng, LU Xu, SHI Cong-ren, TAN Yong, SHAO Zhen, and CAI Hong-xing
In this paper, the additivity principle of scattering spectrum is proved with bidirectional reflectance distribution function theory coupled with the reference of Lambert-Beer law. For planar diffuse system with non-interacting between material particle, there is no interference, diffraction, fluorescence, spectral conIn this paper, the additivity principle of scattering spectrum is proved with bidirectional reflectance distribution function theory coupled with the reference of Lambert-Beer law. For planar diffuse system with non-interacting between material particle, there is no interference, diffraction, fluorescence, spectral conversion, down conversion and other mutual conversion effects between the light source and incident surface material. Furthermore, in the context of non-photochemical phenomenon, nonlinear effects and in accordance with the law of conservation of energy, the material scattering spectrum irradiated by single or multiple light source equal to the linear superposition of the material scattering spectra of each material, which is called the additivity of scattering spectrum. In the experiment, the additivity principle is tested under different lighting conditions and material proportions. It is found that the maximum relative errors are 2.64% and 2.35% for the single and multiple light sources, respectively, which are less than those of theoretical results. Thus, it is shown that the scattering spectrum of material has the additive property which is independent from different lighting conditions and diverse materials and the different proportion of materials. This theory may give a useful method and theoretical reference for extracting feature and recognizing scattering spectra of complex systems. The first propose of the additivity of scattering spectrum provides not only the exact theoretical basis and effective analysis method for the extraction and recognition of complex structures characteristic scattering spectrum and has an important reference value for the experimental analysis and applied research..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1027 (2017)
Research on High Sensitive Detection of HCl Trace Gas Based on QEPAS Technology
MA Yu-fei, HE Ying, YU Xin, YANG Chao-bo, YANG Zhen, BAI Xue-han, and SUN Rui
Hydrogen chloride (HCl) is a toxic and harmful gas. It is of great significance to detecte it with high sensitivity. But up to now there has been a few research reports about the HCl detection using laser spectroscopy. Quartz-enhanced photoacoustic spectroscopy (QEPAS) technology was invented not long ago. This techniqHydrogen chloride (HCl) is a toxic and harmful gas. It is of great significance to detecte it with high sensitivity. But up to now there has been a few research reports about the HCl detection using laser spectroscopy. Quartz-enhanced photoacoustic spectroscopy (QEPAS) technology was invented not long ago. This technique uses a commercially available mm sized piezoelectric quartz tuning fork (QTF) as an acoustic wave transducer. A high Q-factor and a ~32.7 kHz resonance frequency of the QTF improve QEPAS selectivity and immunity to environmental acoustic noise. QEPAS sensor has the advantages of high sensitivity, selectivity and compactness. In this paper, 5 000 ppm HCl∶N2 mixture was selected as the target analyte. A continuous-wave distributed feedback (DFB) single mode diode laser emitting at 1 742.38 μm was used as the exciting source and QEPAS technology was adopted as the detection method. In order to reduce the sensor background noise and simplify the data process, wavelength modulation spectroscopy and a 2nd harmonic detection technique were employed. In this research, acoustic micro-resonator (mR) in the acoustic detection module and the effect of acoustic wave improvement was discussed firstly. The “on beam” architecture of mR was selected and the length and inner diameter of the mR tubes were selected to be 4 and 0.5 mm, respectively. In the experiments, the influence of modulation depth of laser wavelength on QEPAS signal amplitude was investigated. When the acquisition time was 1 sec and modulation depth was 0.23 cm-1, a 1σ minimum detectable concentration limit of 815 ppb was obtained. The corresponding normalized noise equivalent absorption (NNEA) coefficient was 7.41×10-9 cm-1·W·Hz-1/2. In the future, the detection sensitivity can be further improved by adding water vapor into the target HCl gas to enhance the V-T (vibrational-translational) relaxation rate of HCl molecular..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1033 (2017)
Time-Sharing Narrowband CARS Spectroscopy in Olefin Concentration Measurement Applications
YANG Jie, LIU Jin-bo, CAO Rui, CAI Hong-xing, and GUO Jing-wei
A scanning narrowband coherent anti-stokes Raman scattering (CARS) spectrometry was built up for the detection of the production of a variety of hydrocarbon components in the methanol to olefins (MTO) process. Methane, ethane, ethylene, propylene CARS spectra were scanned using this spectrometry; the characteristic RamA scanning narrowband coherent anti-stokes Raman scattering (CARS) spectrometry was built up for the detection of the production of a variety of hydrocarbon components in the methanol to olefins (MTO) process. Methane, ethane, ethylene, propylene CARS spectra were scanned using this spectrometry; the characteristic Raman spectrum of each molecule was obtained. Under the same conditions, the relationships between CARS signal energy and different target molecules and other background gases were studied. A simplified model was established to simulate the CARS signal characteristic peak intensity contributed with different molecules, and the concentrations of Raman active molecules were calculated by this mode. This paper proposed a method of the on-line detection of Raman-active gas concentration by time-sharing narrowband CARS spectra. This method may have practical applications in the online analysis of catalytic chemical industry. The experimental error for the detection of the concentration of methanol, ethylene and propylene is less than 9%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1037 (2017)
Study of Tropospheric NO2 VCD from August 2013 to July 2014 with Ground-Based MAX-DOAS in Hefei and Comparison with OMI Observation
MOU Fu-sheng, LI Ang, XIE Pin-hua, WANG Yang, ZHANG Jie, XU Jin, WU Feng-cheng, and CHEN Hao
The tropospheric NO2 vertical column density (VCD) in Hefei area was studied with groud-based MAX-DOAS data from August 2013 to July 2014.It is shown that tropospheric NO2 VCD season mean and month mean values changed greatly. The maximum value was in the winter while the minimum value was in the summer with the seasonThe tropospheric NO2 vertical column density (VCD) in Hefei area was studied with groud-based MAX-DOAS data from August 2013 to July 2014.It is shown that tropospheric NO2 VCD season mean and month mean values changed greatly. The maximum value was in the winter while the minimum value was in the summer with the season mean value in winter of 2.09×1016 mol·cm-2 whihc was 2.2 times of that in the summer. The research of average diurnal variation in different seasons displayed that biggest discrepancy appeared in the afternoon. Comparison between MAX-DOAS measurements and OMI observations had been conducted and results had an good agreement, especially in cloud-free condition (R2=0.88).The season mean value of tropospheric NO2 VCD around Hefei area from OMI observation showed that high NO2 in Hefei was mainly from local accumulation instead of transportation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1042 (2017)
Research Advance of Variable Selection Algorithms in Near Infrared Spectroscopy Analysis
SONG Xiang-zhong, TANG Guo, ZHANG Lu-da, XIONG Yan-mei, and MIN Shun-geng
Researchers begin to realize that near infrared spectroscopy analysis model can be simplified by removing some redundant variables from the full-spectrum with the growing understanding of near infrared spectroscopy. It is obvious that the simplified model constructed with retained informative variables can be interpretResearchers begin to realize that near infrared spectroscopy analysis model can be simplified by removing some redundant variables from the full-spectrum with the growing understanding of near infrared spectroscopy. It is obvious that the simplified model constructed with retained informative variables can be interpreted more easily. Moreover, both prediction performance and robustness of calibration model can be improved wi hvariable selection, which has been proved in numerous applied examples. Therefore, variable selection has become a critical step in the process of constructing near infrared spectroscopy analysis models, and various kinds of variable selection algorithms and their derivative algorithms have been developed by chemometrics scientists. In order to help the researchers in near infrared spectroscopy analysis field to have a fast overview on variable selection algorithms, we try to review some variable selection algorithms commonly used in near infrared spectroscopy area in this article, including their main rationales and characteristics. These variable selection algorithms are divided into five categories according to their different features. These algorithms are based on parameters of partial least squares (PLS) model, intelligent optimization algorithms, successive projections strategy, model population analysis strategy, and spectral intervals respectively. During the process of carding literatures, we find that the development trends of variable selection algorithms mainly focus on two points: firstly, complexity of new proposed algorithms increaces continually; secondly, the combination of different algorithms becomes more and more popular. Furthermore, we also summarized several specific applied problems that may be occurred when variable selection algorithms are applied in near infrared spectroscopy analysis area. For example, how do different spectral pretreatment methods affect the performance of variable selection algorithm? How to address the poor stability and reliability of some variable selection algorithms?.
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1048 (2017)
Study on Strengthening Mechanism and Performance of Environmental Protection Composite Rubber with Steel Slag Instead of Carbon Black Based on Fourier Transform Infrared Spectroscopy
GU Heng-xing, LI Hui, CHENG Dong-bo, XU De-long, YANG Gang, and CHEN Hua
With the molten iron desulphurization slag as research object, the molten iron desulphurization slag / styrene butadiene rubber was prepared by using molten iron desulphurization slag as rubber filler instead of partial carbon black compound styrene butadiene rubber. The performance of molten iron desulphurization slagWith the molten iron desulphurization slag as research object, the molten iron desulphurization slag / styrene butadiene rubber was prepared by using molten iron desulphurization slag as rubber filler instead of partial carbon black compound styrene butadiene rubber. The performance of molten iron desulphurization slag/styrene butadiene rubber was tested with various methods while the structure of molten desulphurization slag was tested with Fourier transform infrared spectrometer during the different periods of curing process. The results showed that the effect of strengthening and reducing the cost of reinforcing agent can be achieved by using molten iron desulphurization slag instead of partial carbon black. The optimum cure time of molten iron desulphurization slag / styrene butadiene rubber (t90) was 25.08 min, the scorch time was 0~15 min, the thermal curing period was 15~25 min, the curing flat period was 25~45 min. The molten desulphurization slag could provide alkali environment during the scorch time, which was beneficial to increase the liquidity of styrene butadiene rubber. During the thermal curing period and curing flat period, the Ca2SiO4 in the molten desulphurization slag could continue to accelerate the hydration reaction to generate C—S—H gel, which could achieve the effect of strengthening styrene butadiene rubber. In addition, molten desulphurization slag could avoid the emergence of over curing period of molten desulphurization slag/styrene butadiene rubber..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1053 (2017)
Theoretical Analysis and Verification of Prediction Variances and Confidence Limits for Global Temperature Compensation Modeling Approaches
SHI Ting, LUAN Xiao-li, and LIU Fei
Temperature fluctuations affect the action between hydrogen groups, which causes the changes of absorption intensity and peak position of the near infrared (NIR) spectrum, which results in less accuracy of the NIR analyzer. This article studies the prediction accuracy of a type of global temperature compensation modelsTemperature fluctuations affect the action between hydrogen groups, which causes the changes of absorption intensity and peak position of the near infrared (NIR) spectrum, which results in less accuracy of the NIR analyzer. This article studies the prediction accuracy of a type of global temperature compensation models for NIR spectrometric analysis from the aspects of prediction variance and confidence limit respectively. In the designed experiments with continuous temperature changing, NIR spectra are collected with an equal time interval. Hence, the continuous impact on the principal compoments of the NIR spectra caused by temperature is observed and analyzed, which illustrates the mechanism of temperature effection to the model prediction results. As verified by the experimental, the measurement of viscosity of an industrial polymeric material is carried out combined with different modelling methods. According to the experimental verification, the accuracy of non-temperature compensation model and global temperature compensation model are as follows, respectively: RMSEC=0.243 0, Rc=0.871 6, RMSEP=0.243 2, Rp=0.869 3; RMSEC=0.258 2, Rc=0.870 6, RMSEP=0.265 2, Rp=0.856 0. The maximum prediction confidence intervals of these two types of models are about 1.8 and 0.9 kPa·s respectively. Therefore, it can be observed that the modeling accuracy of global temperature compensation model is slightly worse, but the predition precision is much better compared with non-temperature compensated model. Both results of theoretical analysis and experimental verification illustrate that the global temperature compensation modelling methods offer the more accurate models and better robustness and reliability..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1058 (2017)
Study on Diversified Adulteration of Ganoderma Lucidum Spore Oil by RVM and New Clustering Algorithms
WANG Wu, WANG Jian-ming, LI Ying, LI Xiang-hui, and LI Yu-rong
In recent years, food adulteration of various kinds has become a severe problem in food safety detection. In order to get rid of the limitations of traditional qualitative identification of new food adulteration, Fourier transform near-infrared spectroscopy (FT-NIR) was used to collect the spectrum ranging from 12 400 In recent years, food adulteration of various kinds has become a severe problem in food safety detection. In order to get rid of the limitations of traditional qualitative identification of new food adulteration, Fourier transform near-infrared spectroscopy (FT-NIR) was used to collect the spectrum ranging from 12 400 to 4 000 cm-1. The pure ganoderma lucidum spore oil adulterated with peanut oil, corn oil, coix seed oil, and hogwash oil were investigated in this study, where the ganoderma lucidum spore oil adulterated with hogwash oil was taken as the new category of food adulteration. Then, Multiple Relevance Vector Machine (RVM) classifiers were constructed with calibration samples of the first 4 categories. The prediction samples and ganoderma lucidum spore oil adulterated with hogwash oil were discriminated by the 4 kinds of classifier. In addition, the discriminated results were further verified with new clustering algorithm. Results showed that the discriminant accuracy of the first four categories was close to 93.75% with RVM classifier, but the ganoderma lucidum spore oil adulterated with hogwash oil was mistaken for pure ganoderma lucidum spore oil because of the limitations of model. So a new clustering algorithm based on local density and distance decision graph was applied to verify that. It was found that the cluster centers were 1 when the samples only contained pure ganoderma lucidum spore oil, however, the cluster centers were 2 when the samples mixed with pure ganoderma lucidum spore and adulterated with hogwash oil. The results demonstrated the FT-NIR in combination with RVM classifier and new clustering algorithm could be used for the identification of the adulterant in the pure ganoderma lucidum spore oil and qualitatively identify new category of food adulteration, providing a new method to solve the problem of food diversified adulteration..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1064 (2017)
Noninvasive Cerebral Blood Flow Measurement Based on NIRS-ICG
ZHA Yu-tong, LIU Guang-da, WANG Yong-xiang, WANG Te, CAI Jing, ZHOU Ge, and SHANG Xiao-hu
Clinicians take cerebral blood flow (CBF) and other cerebral vascular hemodynamic parameters as diagnostic basis for cerebral blood oxygen and cerebrovascular reserve capability. But current detection methods have disadvantages such as technically complexity and poor universality of reagents or equipments to all diagnoClinicians take cerebral blood flow (CBF) and other cerebral vascular hemodynamic parameters as diagnostic basis for cerebral blood oxygen and cerebrovascular reserve capability. But current detection methods have disadvantages such as technically complexity and poor universality of reagents or equipments to all diagnostic groups. To solve the problems above, a new noninvasive, rapid and repeated technique for measurement of CBF by combination of near-infrared spectroscopy (NIRS) and indocyanine green (ICG) pulse-dye densitometry is proposed by the name of NIRS-ICG. After ICG intravenous bolus injection, concentration curves of three main chromophores, which are oxygenated hemoglobin, reduced hemoglobin and ICG, in both brain tissue and cerebral artery, are estimated. And then ICG accumulation rate and introduced quantity models are established in order to obtain CBF and other cerebral vascular hemodynamic parameters. To verify the feasibility of this method, CBF and other parameters of normocapnia piglet and hypercapnia piglets were detected in NIRS-ICG. 3, 6 and 9 percent of CO2 mixed with air was mechanical ventilated into four group Chinese experimental miniature pigs. NIRS-ICG was used to measure CBF, cerebral arterial oxygen saturation (SaO2), and mean transit time (MTT) after rapidly intravenous infusion of ICG. The test value showed that CBF increased with the increase of CO2 ratio, SaO2 decreased with the increase of CO2 ratio, and MTT had no significant change. It is proved that the measurements reflected changes in cerebral blood flow reliably. NIRS-ICG is applicable both in cerebral blood oxygen and cerebrovascular reserve capability detection..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1069 (2017)
Study for the Photon Propagation Properties in Biological Tissue Based on Frequency-Domain Near-Infrared Spectroscopy
HU Wen-yan, LIU Hui, WANG Yu-heng, LI Jun-hui, ZHANG Xiao-shuan, WANG Zhong-yi, and ZHAO Long-lian
Based on the theory of photon radiative transfer in biological tissue and Feng model, we applied frequency-domain near-infrared spectroscopy to study the position changes of the little ball in the biological tissue how to influence the intensity and phase of emergent light, and learn if there are regularities of the inBased on the theory of photon radiative transfer in biological tissue and Feng model, we applied frequency-domain near-infrared spectroscopy to study the position changes of the little ball in the biological tissue how to influence the intensity and phase of emergent light, and learn if there are regularities of the intensity and phase changing. A simulation experiment was designed using the milk as biological tissue and a little ball as the tissue lesions. The ball was fixed to a thin rod and allowed to be moved up and down in the milk. At every step of the little ball, data of AC, DC and Phase were collected and stored in files that were then converted to waveform in Matlab. According to the results of the experiment, the variation trend of the AC and DC plot were displayed same, and the phase plot does indeed display the biphasic behavior. The valleys of the AC, DC and Phase plots were all offset to the right with the increasing of distance between light sources and detectors. And the greater degree of ball deviating from the light sources and detectors, the smaller effects that the ball acted on intensity and phase detected. With the discussion of the results, we could finally delve into the heart of this set of experiments, which was to show that the photons transmission was confirmed concerning the theory of radiative transfer. This research also established foundation to detect the tissue parameters and locate the position of tissue lesions by frequency-domain near-infrared spectroscopy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1074 (2017)
Study on Detection of Talcum Powder in Green Tea Based on Fourier Transform Infrared (FTIR) Transmission Spectroscopy
LI Xiao-li, ZHANG Yu-ying, and HE Yong
This paper studied the feasibility to detect talcum powder illegally added in tea based on Fourier transform infrared (FTIR) transmission spectroscopy with chemometric methods. In this study, 210 tea samples with 12 dose concentrations of talcum powder were prepared for FTIR spectra acquirement. Firstly, Savitzky-GolayThis paper studied the feasibility to detect talcum powder illegally added in tea based on Fourier transform infrared (FTIR) transmission spectroscopy with chemometric methods. In this study, 210 tea samples with 12 dose concentrations of talcum powder were prepared for FTIR spectra acquirement. Firstly, Savitzky-Golay (SG) smoothing, normalize and standard normal variate (SNV) were used to preprocess the raw spectra. It was shown that SNV preprocessing had the best performance. After that, a hybrid method of backward interval partial least squares (biPLS) regression and successive projections algorithm (SPA) was used to select 5 characteristic wavenumbers, which only accounted for 0.18% of the whole wavenumbers. Then, PLS regression and least square support vector machine (LS-SVM) were utilized to build linear and nonlinear models based on these 5 characteristic wavenumbers, respectively. Finally, the optimal model was achieved with LS-SVM with highRP=0.921 and low RMSEP=0.131. It concluded that talcum powder in green tea could be detected based on FTIR spectroscopy coupled with chemometrics..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1081 (2017)
Preliminary Research on the Adaptability of NIR Quantitative Calibration Models for Metal Elements in Soil
WANG Dong, MA Zhi-hong, WANG Ji-hua, JIN Xin-xin, HOU Jin-jian, and PAN Li-gang
In order to research the adaptability of the NIR quantitative calibration models for the metal elements in soil, in this research, near-infrared spectroscopy combined with partial least square regression algorithm was applied to develop the quantitative calibration models of K, As, Hg, Cu, Zn, Pb, Cr, Cd in the air-dryIn order to research the adaptability of the NIR quantitative calibration models for the metal elements in soil, in this research, near-infrared spectroscopy combined with partial least square regression algorithm was applied to develop the quantitative calibration models of K, As, Hg, Cu, Zn, Pb, Cr, Cd in the air-dry soil samples after the outliers having been eliminated. The content prediction of the elements mentioned above was carried out for the air-dry soil samples and the oven-dry soil samples for the external validation set respectively. The result indicates that the correlation coefficient between the estimated and specified values of the air-dry soil samples is larger than that of the oven-dry soil samples for each element. A significant correlation exists between the estimated and specified values of the air-dry soil samples for each element, while there is no significant correlation exists between that of K, Hg, Cr of the oven-dry soil samples. In this thesis, the adaptability of the NIR quantitative calibration models for the metal elements in soil was researched preliminarily, which, to some extent, can provide reference for the rapid quantitative monitoring method of the metal elements in soil and the monitoring of the home environment of agricultural products..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1086 (2017)
Study of Sabina Chinensis Heartwood and Sapwood Pyrolysis with TG-FTIR Analysis
WANG Zhen-yu, QIU Shu, HE Zheng-bin, YI Song-lin, and MU Jun
Biomass pyrolysis is one of the most important means to realize effective treatment and efficient utilization of biomass wastes and materials. Therefore, it has great practical significance to research the process and mechanism of biomass pyrolysis. Wood, as a renewable material with a rich source , is a kind of pyrolyBiomass pyrolysis is one of the most important means to realize effective treatment and efficient utilization of biomass wastes and materials. Therefore, it has great practical significance to research the process and mechanism of biomass pyrolysis. Wood, as a renewable material with a rich source , is a kind of pyrolysis raw material among lots of biomass. As we all know, because of the difference of composition and other aspects, pyrolysis characteristics of different tree species have obvious differences. However, even the same kind of wood such as the heartwood and sapwood of lumber show different pyrolysis characteristics and products in the process of pyrolysis, due to the significant differences in such aspects as microstructure, chemical composition and the amount of each component, which is studied feild in this paper. In the experiment, sabina chinensis, a kind of common landscaping, are taken as test material, whose heartwood and sapwood are clearly distinct. In order to research the pyrolysis differences between heartwood and sapwood, TG-FTIR method is used to obtain the thermogravimetric curves and volatile spectrograms during the process. Results elucidated that the content of cellulose, hemicellulose, lignin and extracts have a remarkably effect on both heartwood and sapwood. On account of higher content of hemicellulose and lignin, the heartwood of sabina chinensis showed higher weight loss ratio than sapwood during the early and late stages. Whats more, higher content of extracts increased the weight loss ratio of heartwood in the medium stage, which reduced the differences between heartwood and sapwood. On contrary, sapwood with more cellulose had more obvious weight loss during 300~380 ℃ and higher weight loss ratio in the DTG curve. In addition, the infrared spectrum indicated that both heartwood and sapwood produced almost same volatiles, but there were differences in amount. And when the pyrolysis came to the maximum weight loss velocity, volatiles produced increased significantly. Moreover, sapwood produced more organic compounds, while heartwood produced more water and CO2..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1090 (2017)
Study on an Algorithm for Near Infrared Spectrum Multiclass Identification and Measurement Based on Feature Hierarchical Selection and Sample Fusion Degree
ZHU Cheng, GONG Hui-li, DING Xiang-qian, and HOU Rui-chun
Aiming at solving the difficulty of getting the best feature subset from high dimensional and the low identification accuracy of existing models, this paper proposes an algorithm for near infrared spectrum identification and measurement based on feature hierarchical selection and sample fusion degree. The paper firstlyAiming at solving the difficulty of getting the best feature subset from high dimensional and the low identification accuracy of existing models, this paper proposes an algorithm for near infrared spectrum identification and measurement based on feature hierarchical selection and sample fusion degree. The paper firstly introduces the concept of jump degree, and proposes a feature hierarchical method to divide all the features into different subsets in terms of their importance to sample, which avoid the complicated process of deleting unrelated features one by one when constructing feature subset from the original feature data; At the same time, this paper improves sample fusion degree, while regarding it as the category judgment type of the improved KNN algorithm that take the place of probability, which has increased the precision of multiclass identification. The low identification accuracy was solved better though it. In order to verify the validity of our algorithm, five kinds of 382 representative tobacco samples were chosen as the experimental objects to build tobacco producing area identification models and 64 tobacco samples were chose as test samples; At last, with Root Mean Square Error of Prediction (RMSEP), Root Means Square Error of Cross Validation (RMSECV) and Correlation Coefficient (r) as the evaluation index of stability and identification accuracy as evaluation standard, the algorithm above made a comparison with other algorithms. The experimental results show that the model constructed by our algorithm has better stability with lower RMSEP (0.117), RMSECV (0.106) and higher r (0.973). The identification accuracy of our algorithm is the highest, reaching at 98.44%. The algorithm proposed in this paper has an excellent identification performance for high dimensional spectral data..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1095 (2017)
Rapid Quality Evaluation of Anxi Tieguanyin Tea Based on Genetic Algorithm
WANG Bing-yu, SUN Wei-jiang, HUANG Yan, YU Wen-quan, WU Quan-jin, LIN Fu-ming, and XIA Jin-mei
Anxi Tieguanyin tea was collected as the research materials in this study. In order to find a fast and non-destructive method for rapid quality evaluation of Anxi Tieguanyin tea, the Genetic Algorithm (GA) was applied to wavelength selection befoe it is combined with partial least squares (PLS) to construct PLS and GA-Anxi Tieguanyin tea was collected as the research materials in this study. In order to find a fast and non-destructive method for rapid quality evaluation of Anxi Tieguanyin tea, the Genetic Algorithm (GA) was applied to wavelength selection befoe it is combined with partial least squares (PLS) to construct PLS and GA-PLS calibration model. The results showed that the PLS model displayed the highest prediction performance after the Fourier transform near-infrared (FT-NIR) spectrum being processed by smoothing, the second derivative and normalized methods. Statistic results with PLS: RC=0.921, RMSEC=0.543, RP=0.913, RMSEP=0.665. NIR spectra ranging from 6 670 to 4 000 cm-1 were selected, and 1 557 data volume for building calibration model were reduced to 408 with Genetic algorithm. Statistic results with GA-PLS: RC=0.959, RMSEC=0.413, RP=0.940, RMSEP=0.587. It has shown that the prediction precision of calibration set and validation set of GA-PLS model is better than those of PLS model. According to the results, it can effectively improve the prediction ability of the model when the Genetic Algorithm (GA) is applied to select the wavelengths in a traditional model which is based on the near infrared spectroscopy combined with partial least squares. It can also achieve the innovation of the methodology. Furthermore, the quality evaluation GA-PLS model provides strong reference and possesses promotional value. In addition, it provides valuable reference and new avenue for improving the standard of detection technology of tea quality in China..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1100 (2017)
Detection of Adulterated Sesame Oil Based on Synchronous-Asynchronous Two-Dimensional Mid-Infrared Correlation Spectroscopy
YU Ge, YANG Ren-jie, L Ai-jun, and TAN En-zhong
An innovative method for classification of adulterated sesame oil was applied by using synchronous-asynchronous two-dimensional (2D) mid-infrared correlation spectroscopy in combination with way partial least squares discriminant analysis (NPLS-DA). 40 pure sesame oils and 40 adulterated sesame oils with corn oil (3%~6An innovative method for classification of adulterated sesame oil was applied by using synchronous-asynchronous two-dimensional (2D) mid-infrared correlation spectroscopy in combination with way partial least squares discriminant analysis (NPLS-DA). 40 pure sesame oils and 40 adulterated sesame oils with corn oil (3%~60%) were prepared and one-dimensional (1D) infrared absorption spectra(650~4 000 cm-1) were measured at room temperature. 1D spectral characteristics of pure and adulterated sesame oil were studied. Under the perturbation of the concentration of corn oil in sesame oils, the synchronous and asynchronous 2D mid-infrared correlation spectra were calculated and normalized. Synchronous-asynchronous 2D mid-infrared correlation matrix was obtained by computing the sum of the upper triangular part of the normalized synchronous 2D mid-infrared correlation matrix and the strictly lower triangular part of the normalized asynchronous 2D mid-infrared correlation matrix. The qualitative analysis NPLS-DA models were constructed to classify adulterated sesame oil by using synchronous-asynchronous 2D mid-infrared correlation spectra, synchronous 2D mid-nfrared correlation spectra, and asynchronous 2D mid-nfrared correlation spectra. For samples in prediction set, the rate of correct classification was 100% by using synchronous-asynchronous 2D mid-infrared correlation spectra, versus 96.2% by using synchronous and asynchronous 2D mid-infrared correlation spectra. Compared with synchronous, or asynchronous 2D mid-infrared correlation spectra, synchronous-asynchronous 2D mid-infrared correlation spectra not only contain more integrated characteristic information of adulterated oil, but also eliminate redundancy. Therefore, synchronous-asynchronous 2D mid-infrared correlation spectra can provide better classification results..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1105 (2017)
Determination of Osthole and Columbianadin in Angelicae Pubescentis Radix with Near Infrared Spectroscopy
ZHAN Hao, FANG Jing, YANG Bin, FU Mei-hong, LIU Meng-ting, LI Hua, WANG Zhu-ju, TANG Li-ying, WU Hong-wei, YANG Lan, and ZHANG Dong
Near infrared spectroscop is applied to establish a rapid detection method of osthole and columbianadin in Angelicae pubescentis Radix. Near infrared spectroscopy (NIR) has become a new analytical technique for quantitative analysis of Chinese medicinal materials because of its rapid analysis speed and no need for sampNear infrared spectroscop is applied to establish a rapid detection method of osthole and columbianadin in Angelicae pubescentis Radix. Near infrared spectroscopy (NIR) has become a new analytical technique for quantitative analysis of Chinese medicinal materials because of its rapid analysis speed and no need for sample pretreatment. 97 batches of samples are collected from different regions with the determination of samples with high performance liquid chromatography (HPLC) and NIR. Due to subtle difference between the spectra, it needs to preprocess by comparing the results of different pretreatment methods to select the optimal model parameters. The results showed that the pretreatment method for the first derivative, osthole in performance optimization model, the determination coefficients was 0.941 3 while the root mean square prediction (RMSEP) was 0.141; determination coefficients of calibration set was 0.923 3, and the root mean square error of calibration (RMSEC) was 0.163. Without pretreatment of columbianadin model in optimal performance, the determination coefficients was 0.857 4 and the root mean square prediction was 0.103; when the determination coefficients of calibration set was 0.831 5, and the root mean square error of calibration was 0.112. Studies have shown that the near infrared spectroscopy combined with partial least squares method is simple, rapid, efficient and nondestructive which can achieve the goal in terms of quantitative analysis for quality control of medicines research with osthole and columbianadin in Angelicae Pubescentis Radix. At the same time a new method for the development of near infrared spectroscopy technology of traditional real-time analysis is proposed, it also has great significance to guarantee the stability of Chinese medicinal materials quality control..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1110 (2017)
Research on Optimization of Wheat Seed Germination Rate NIR Model Based on Si-cPLS
WU Jing-zhu, DONG Wen-fei, DONG Jing-jing, CHEN Yan, MAO Wen-hua, and LIU Cui-ling
To improve the detecting accuracy and robustness of wheat seed germination rate with near infrared spectroscopy technique, single PLS model and consensus PLS model(cPLS) developed on the full-spectral were compared and analyzed, thus, the Si-cPLS model which developed on the characteristic spectral regions was put forwTo improve the detecting accuracy and robustness of wheat seed germination rate with near infrared spectroscopy technique, single PLS model and consensus PLS model(cPLS) developed on the full-spectral were compared and analyzed, thus, the Si-cPLS model which developed on the characteristic spectral regions was put forward. There were 84 samples partitioned into 66 training samples and 18 prediction samples using SPXY method. By randomly selecting 50 samples from training set as calibration set, a series of sub PLS models were build. 100 PLS sub models satisfying predefined criterion were selected and combined one cPLS model by averaging all predicted results. With this basis Si-cPLS model were developed on characteristic spectral regions selected with synergy interval method. Statistics on 50 repeat prediction of wheat seed germination by full-spectral PLS model, full-spectral cPLS model, and Si-cPLS model showed that, the mean correlation coefficient(R) were 0.901, 0.922 and 0.936 respectively, the mean RMSEP were 13.735%, 12.533% and 10.273% respectively with standard deviation of RMSEP of 1.144%, 0.096% and 0.080% respectively. Results showed that cPLS model was more stable and reliable than single PLS model, While Si-cPLS could further increase the stability and prediction accuracy of cPLS model..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1114 (2017)
Determination of Methanol Content in Methanol Diesel Based on Near Infrared Spectroscopy
OUYANG Ai-guo, HUANG Zhi-hong, and LIU Yan-de
Near infrared spectroscopy combined with chemometric resolution method was applied to analyze methanol content in methanol diesel quantitatively. In this experiment, 32 samples of methanol diesel in the range of 2%~25.8% (φ) were used for spectroscopy collection and analysis. Three quantitative analysis models of partiNear infrared spectroscopy combined with chemometric resolution method was applied to analyze methanol content in methanol diesel quantitatively. In this experiment, 32 samples of methanol diesel in the range of 2%~25.8% (φ) were used for spectroscopy collection and analysis. Three quantitative analysis models of partial least squares (PLS), support vector machine (SVM) and least squares support vector machines (LS-SVM) were established in the range of 4 500~70 000 cm-1. The Radial Basis Function (Radial Basis Function, RBF) was the optimal kernel function of the SVM model compared three different kinds of prediction model during process of building the SVM model. The research results showed correlation coefficient (RP) and the root mean square error of prediction (RMSEP) of PLS, SVM and LS-SVM were 0.985 9, 0.990 3, 0.998 9 and 0.405 2, 0.356 3, 0.062 4 respectively. It was obviously that the three kinds of prediction model could obtain better results especially with LS-SVM modeling. The research results indicated that near infrared spectroscopy combined with chemometrics resolution method could achieve better results when used for detecting methanol content in methanol diesel. Moreover, using near infrared spectroscopy combined with chemometric resolution method to analyze methanol content in methanol diesel quantitatively may have reference value and application potentiality for near infrared spectroscopy quick and non-destructive test of methanol content in methanol diesel..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1118 (2017)
The Application and Progress of Laser Tweezers Raman Spectroscopy in Biomedicine
LI Zhi-hua, ZHENG Zu-ci, WENG Cun-cheng, LIN Duo, WANG Qi-wen, and FENG Shang-yuan
Laser tweezers Raman spectroscopy (LTRS) integrating with optical tweezers with confocal Raman spectroscopy ensures the trapping, manipulation, measurement and biochemical analysis under physiological conditions for the single living cell analysis in suspension. Due to the unique advantage in single-cell research, LTRSLaser tweezers Raman spectroscopy (LTRS) integrating with optical tweezers with confocal Raman spectroscopy ensures the trapping, manipulation, measurement and biochemical analysis under physiological conditions for the single living cell analysis in suspension. Due to the unique advantage in single-cell research, LTRS has drawn more and more attention. In this review, the biomedical applications and the development of laser tweezers Raman spectroscopy in recent years are taken as the main line, centering around the four areas: Raman spectroscopy in the analysis of cell and cell sorting, multi-optical tweezers Raman spectroscopy systems, micro-fluidic transport systems and the technology of multi-mode analysis, to summarize the recent development of LTRS in multi-data acquisition and integration, high efficiency, high-throughput and the transport of automation by combination with other novel techniques or upgrading technologies. At the same time, the technology applied in biomedicine is introduced. Finally, a perspective of the future development for the powerful cell analysis technology is presented..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1123 (2017)
A SERS Study on Self-Assembly Process of 1-Hexanethiol on Ag Nanoparticles: Effects on Adsorption Time and Concentration
LUAN Xin-tong, ZHOU Tie-li, SUN Cheng-bin, TAO Yan-chun, ZHAO Bing, WANG Xu, and RUAN Wei-dong
Surface-enhanced Raman scattering (SERS) is an ultra-sensitive spectroscopic technique which has great application prosepct in characterization of dynamic molecular structures. Self-assembled monolayers (SAMs) of alkanethiolates are a typical kind of ultrathin films which have tremendous applications in the fields of bSurface-enhanced Raman scattering (SERS) is an ultra-sensitive spectroscopic technique which has great application prosepct in characterization of dynamic molecular structures. Self-assembled monolayers (SAMs) of alkanethiolates are a typical kind of ultrathin films which have tremendous applications in the fields of bionics, materials, electronics, biology and chemistry. In the present study, the SAM structures of 1-hexanethiol when adsorbing on Ag nanoparticles were explored. The vibrational modes of trans (T) and gauche (G) conformations were employed to illustrate the molecular structures. The intensity ratios of T and G bands concerning to C—S, C—C and CH3 groups indicate the crystallinity of the SAMs. The results show that when HT is in high concentrations the crystalline process is quick, while in low concentrations, the crystalline process is very slow. The dynamic study on the formation of SAM films is of great significance for the corrosion protection, device fabrication, and sensor applications..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1130 (2017)
Study on Drug Groups in Huo-Xue-Hua-Yu Decoction with Surfaced-Enhanced Raman Scattering Spectroscopic
CHEN Wei-wei, LIU Yu, SHI Hong, YU Yun, LIN Duo, FENG Shang-yuan, LIN Jia, HUANG Hao, and CHEN Rong
In integrated treatment of traditional Chinese medicine, prescriptions are used as carriers. Attention has been given to the integration, and the methodology of treatment is based on syndrome differentiation. To reveal the rule of drug group in prescription, according to the own drug efficacy of traditional Chinese medIn integrated treatment of traditional Chinese medicine, prescriptions are used as carriers. Attention has been given to the integration, and the methodology of treatment is based on syndrome differentiation. To reveal the rule of drug group in prescription, according to the own drug efficacy of traditional Chinese medicine, Huo-Xue-Hua-Yu decoction (HXHYD) was divided into four drug-group decoctions as follow: Tiao-He drug group decoction (THDGD), Hua-Yu-Sheng-Xin drug group decoction (HYSXDGD), Huo-Xue-Zhi-Tong drug group decoction (HXZTDGD) and Bu-Qi drug group decoction (BQDGD). There are strong interactions between Ag nanoparticles and decoction, thus leading to a tremendous enhancement in the intensity of the decoction Raman scattering, the Surface-enhanced Raman Scattering (SERS) spectroscopy of HXHYD, THDGD, HYSXDGD, HXZTDGD and BQDGD were obtained and analyzed, and the characteristic Raman bands of five decoctions were tentatively assigned. Mainly eighteen Raman signals (523, 538, 622, 647, 732, 959, 977, 1 003, 1 048, 1 077, 1 145, 1 245, 1 326, 1 402, 1 456, 1 470, 1 518 and 1 605 cm-1) in five decoctions were discussed. Some Raman bands in SERS spectra of drug group decoctions were retained in the HXHYD, such as 538, 622, 647, 732, 959, 1 003, 1 048, 1 326, 1 402, 1 456, 1 470, 1 518 and 1 605 cm-1. However some Raman bands never appeared in the HXHYD, such as 1 077, 1 145 and 1 245 cm-1. New Raman bands were generated in the SERS spectra of HXHYD, such as 523 and 977 cm-1, which meant new created chemical compositions. The results showed that medical ingredients in the HXHYD were not the simple addition of THDGD, HYSXDGD, HXZTDGD and BQDGD, and SERS technique has great potential for providing a novel method for effectively and accurately studying drug group rule of prescription..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1134 (2017)
Quantitative Approach to Determination of δ13C Value of CO2 with Micro-Laser Raman Spectroscopy
LI Jia-jia, LI Rong-xi, DONG Hui, WANG Zhi-hai, ZHAO Bang-sheng, and CHENG Jing-hua
Stable isotope of individual fluid inclusion has great significance in researching the formation of rock and mineral paleo-fluid, geology of ore deposits, oil/gas mineral deposits and geodynamics of tectonic evolution. Micro-Laser Raman analysis is a method for stable isotopes in single fluid inclusions. This study proStable isotope of individual fluid inclusion has great significance in researching the formation of rock and mineral paleo-fluid, geology of ore deposits, oil/gas mineral deposits and geodynamics of tectonic evolution. Micro-Laser Raman analysis is a method for stable isotopes in single fluid inclusions. This study proposed a method to calculate δ13C value with Micro-Laser Raman spectroscopy. 12CO2 and 13CO2 mixed with N2 at various molar fraction ratios respectively through self-devised experimental apparatus. The determination of Raman parameters provides theoretical basis for calculating the δ13C value. Based on the study of principles and feasibility of the method of laser Raman spectroscopy, a series of known molar fractions of 12CO2/13CO2 binary mixtures as artificial CO2 fluid inclusions have been prepared. The artificial CO2 fluid inclusions and CO2 gas from Shengli Oil-field have been analyzed with Micro-Laser Raman analysis method. And the molar fraction ratio N13/N12 is related to Raman parameters, the value of δ13C could be calculated by formula δ13C=［(C13/C12)sample/(C13/C12)PDB-1］×1 000‰. The δ13C value of CO2 gas from Shengli Oil-field is -5.6‰ and -5.318 ‰ by using mass spectrometry and Micro-Laser Raman analysis method, respectively. The results demonstrate that it builds up a way to determine δ13C Value of CO2 with Micro-Laser Raman Spectroscopy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1139 (2017)
Research on Fluorescence Spectral Characteristics of Phycocyanin under Different Habitat Conditions
ZHANG Xiao-ling, YIN Gao-fang, ZHAO Nan-jing, QIN Zhi-song, XIAO Xue, DUAN Jing-bo, YANG Rui-fang, TU Meng-di, LIU Jian-guo, and LIU Wen-qing
The development of cyanobacterial biomass detection technology is an important part to deal with the frequent occurrence of water bloom events. Phycocyanin, to some extent, as a special protein of cyanobacteria, is more accurate reaction in natural water cyanobacterial biomassthan chlorophyll, thus become an important The development of cyanobacterial biomass detection technology is an important part to deal with the frequent occurrence of water bloom events. Phycocyanin, to some extent, as a special protein of cyanobacteria, is more accurate reaction in natural water cyanobacterial biomassthan chlorophyll, thus become an important index in cyanobacterial biomass detection. This paper, with different light intensity and different growth stages as the research objects. compares the reliability of the two methods of the envelope method and the single point method , exploring the fluorescence spectral characteristics of phycocyanin in vivo Microcystis Anabaena by using three-dimensional fluorescence spectroscopy. The results show that: (1) The fluorescence intensity increases with the growth of long-term; (2) It is more reliable to use envelope method to analyze the characteristic fluorescence spectra of the fluorescent spectrum than the single point method. (3) The fluorescence spectra of Phycocyanin in vivo Microcystis were basically unchanged in EX=614 nm/ EM=654 nm. The excitation wavelength of the phycocyanin fluorescence in vivo Microcystis decreases with the growth with 610 and 620 nm in the long term, and the emission wavelength varied between 650 and 660 nm, which is related to the sample particle size and spectral scanning mode. This study provided the experimental basis for the development of the fluorescent detection technology of cyanobacteria..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1145 (2017)
Effect of Soil Moisture Content on the Fluorescence Characteristics of Polycyclic Aromatic Hydrocarbons
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Fluorescence spectroscopy has been used to detect polycyclic aromatic hydrocarbons (PAHs) in soil. However, the soil moisture has a strong interference to the fluorescence intensity of PAHs, which is a challenge to the development of the rapid real-time detection technology of PAHs in soil. In order to analyze the effeFluorescence spectroscopy has been used to detect polycyclic aromatic hydrocarbons (PAHs) in soil. However, the soil moisture has a strong interference to the fluorescence intensity of PAHs, which is a challenge to the development of the rapid real-time detection technology of PAHs in soil. In order to analyze the effect of soil moisture on the fluorescence characteristics of PAHs, 8 phenanthrene contaminated soil samples were prepared with different moisture content (5%~40%, interval of 5%). The dynamic one-dimensional fluorescence spectra of soil samples with different moisture content were obtained by LS-55 fluorophotometer. Two-dimensional (2D) correlation fluorescence spectrum was calculated under the perturbation of soil moisture content. It was found that the fluorescence intensity of phenanthrene at 386, 408 and 432 nm enhanced with the increase of soil moisture content, while the Rayleigh scattering light intensity at 333 nm was decreased. And, it is pointed out that the effect of soil moisture on fluorescence can be corrected by establishing the relationship among fluorescence intensity, Rayleigh scattering intensity and soil moisture content. Meanwhile, the effect of soil moisture on the standard curve of phenanthrene concentration was studied. It is demonstrated that the soil moisture has a great influence on the quantitation of phenanthrene..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1152 (2017)
Application of Fluorescence Spectrometry Combined with Fisher Discriminant Analysis in Radix Panacis Quinquefolii Identification
CHEN Jia-wei, HU Cui-ying, and MA Ji
The purpose of this paper was to establish a reliable Fisher discriminant model which was able to recognize the decoction pieces of radix panacis quinquefolii and its common counterfeits rapidly, objectively and accurately. The fluorescence spectra of 90 samples (decoction pieces of radix panacis quinquefolii, radix gThe purpose of this paper was to establish a reliable Fisher discriminant model which was able to recognize the decoction pieces of radix panacis quinquefolii and its common counterfeits rapidly, objectively and accurately. The fluorescence spectra of 90 samples (decoction pieces of radix panacis quinquefolii, radix ginseng and platycodon grandiflorum each 30 copies) that from different source were detected by a self-build staring spectral imaging instrument in this study. The experimental parameters included spectral wavelengths range from 400 to 720 nm, with the interval of 5 nm. Standard normal variate (SNV) transformation was used for spectral pretreatment, to reduce the noise information in original spectral data. According to the principle features and optimizing effect of principal component analysis (PCA) and stepwise discriminant analysis (SDA), PCA in combination with PCA was needed. At first, SNV spectral data was processed with PCA to obtain main information of spectrum distributed in the first few principal components. Then 12 principal components that with strong discriminant ability were selected from 65 principal components, and used for established the Fisher discriminant model. All kind of samples showed up a good clustering phenomenon in the scatter diagram, which plotted based on samples scores in two discriminant functions. In order to obtain an accurate discriminant result of the model, the Euclidean distance between the central of each species and the samples that under discriminate was calculated and as the gist. The result showed that the discriminant accuracy of the Fisher discriminant model in training set and prediction set was 98.33% and 96.67% respectively, demonstrating that the superior reliability and accuracy existed in the model. Therefore, fluorescence spectroscopy combined with Fisher discriminant analysis could be applied to the rapid identification between the decoction pieces of radix panacis quinquefolii and its counterfeits..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1157 (2017)
Data Compression of Time Series Three-Dimensional Fluorescence Spectroscopy
YU Shao-hui, XIAO Xue, and XU Ge
There has been abundant data saved in time series three-dimensional fluorescence spectroscopy, which is helpful to the qualitative and quantitative analysis of organic matter. However, redundant information also complicates the analysis and decreases the computation efficiency. Based on time-frequency of time series thThere has been abundant data saved in time series three-dimensional fluorescence spectroscopy, which is helpful to the qualitative and quantitative analysis of organic matter. However, redundant information also complicates the analysis and decreases the computation efficiency. Based on time-frequency of time series three-dimensional fluorescence spectroscopy, three-dimensional fluorescence spectroscopy is compressed with cluster analysis and 2-D wavelet transform. Some key factors, such as sample distance, inter-calss distance, composite correlation coefficient and R-square stastic, are discussed. The introductions of correlation coefficient and R-square statistic not only improve the precision of cluster analysis but also reduce the data for 2-D wavelet transform. Experiment results show that the important information in the original data is still kept in the compressed time series three-dimensional fluorescence spectroscopy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1163 (2017)
Research on the Fluorescence Properties of Synthetic Pigment Sunset Yellow and Allura Red
ZHAO Jin-chen, CHEN Guo-qing, ZHU Chun, WU Jian-chun, WU Ya-min, ZHU Zhuo-wei, GU Song, DU Jia-meng, and XI Liu-hua
For sunset yellow and allura red, the fluorescence spectra have been measured with British Edinburgh FLS920 Steady and Time-Resolved Fluorescence Spectrometer. Two geometries which involve the ground state and the excited state of sunset yellow and allura red are constructed by utilizing Gaussian 09W software. Based onFor sunset yellow and allura red, the fluorescence spectra have been measured with British Edinburgh FLS920 Steady and Time-Resolved Fluorescence Spectrometer. Two geometries which involve the ground state and the excited state of sunset yellow and allura red are constructed by utilizing Gaussian 09W software. Based on the density functional theory and time-dependent density functional theory, the optimization and calculation about the ground state as well as the excited one are completed. The MPWK function and 6-31g (d) basis sets are applied during the optimization process. Compared with the function and basis sets in the former job, the B3LYP functional and 6-311g (d, p) basis sets are employed when the calculation is carried out. With the consideration of the influence of the solvent effects on the calculation results, thereby, it is necessary to add the polarized continuum model. In the end, the calculated fluorescence spectra are compared with the experimental measurement of spectra, respectively, the results about sunset yellow show that the calculated fluorescence peak at 435 nm which has a relative error of 3.57%, compared with the 420 nm by experiment. For allura red, the calculated fluorescence peak at 443 nm, which means a relative error of 2.55% exists, compared with the 432 nm by experiment. That is to say, for the fluorescence peak of sunset yellow and allura red, their relative errors are in the reasonable range. In a word, the calculation results show that the calculated fluorescence peaks are advisable. When studying the fluorescence properties of two molecules, we find the fluorescence peaks are related to intramolecular charge transfer..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1168 (2017)
Research on Target Recognition System for Camouflage Target Based on Dual Modulation
LI Dong-ming, BI Hai-ping, LIU Zhi-chao, YANG Jin-hua, ZHANG Li-juan, WANG Liang, and CHEN Gui-fen
In order to achieve effective detection target covered by camouflage nets, and to improve recognition ability to camouflage target, a target recognition system was designed based on the electro-optical and magneto-optical dual modulation. The system was composed of polarizer, electro-optical modulation module, magneto-In order to achieve effective detection target covered by camouflage nets, and to improve recognition ability to camouflage target, a target recognition system was designed based on the electro-optical and magneto-optical dual modulation. The system was composed of polarizer, electro-optical modulation module, magneto-optical modulation module, analyzer, photoelectric detectors and other components. It produced the modulation function combination of electro-optical modulation and magneto-optical modulation, and the composite modulation function was derived. On the basis of vector analysis, the impact of the function of the intensity of echo light was analyzed with the modulation parameters for electro-optical and magneto-optical. In the experiment, a square steel side length of 1m was used as the test target, and two kinds of commonly camouflage nets were used for target detection in different background environments. Under different polarization angles conditions, the response voltage of echo light was tested and analyzed. Experimental results show that there are obvious response peak for the target and camouflage nets, however, because of the different position and angle of the target, the peak position is different. At the same time, the intensity of echo light from the background can not generate a strong response voltage. Therefore, the extreme signal of response voltage can be obtained to identify a camouflaged target in the entire magneto-optical modulation cycle. As for wavelength variable experiments, it had a certain influence for echo peak and background noise caused by the changes of the light source wavelengths. Therefor, it can be adjusted by the source wavelength increasing the SNR of target image. In short, the system has a good recognition ability for camouflage target..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1174 (2017)
Application of Machine Learning in Determination of Nitrate Nitrogen Based on Ultraviolet Spectrophotometry
LIU Si-xiang, FAN Wei-hua, GUO Hui, ZHAO Hui, and JIN Qing-hui
Ultraviolet spectrophotometry has been widely applied in determination of water quality parameters because of its advantagous properties compared to chemical method, such as high efficiency, easy operation and non-secondary pollutions. Nitrate nitrogen is one of major pollutants in waste water. The standard ultravioletUltraviolet spectrophotometry has been widely applied in determination of water quality parameters because of its advantagous properties compared to chemical method, such as high efficiency, easy operation and non-secondary pollutions. Nitrate nitrogen is one of major pollutants in waste water. The standard ultraviolet spectrophotometry used to determinate the concentration of nitrate nitrogen in water is firstly to determinate the absorbances at wavelength 220 and 275 nm, which is used to calibrate the former, followed by the plotting of standard curve. While the linear equation described by Lambert-Beers law and the linearity in the superposition of absorbances of various substance, on which the standard ultraviolet spectrophotometry based, are not fitted well anymore with the increase of concentration. In addition, it was found to be difficult to construct absorption model of nitrate solution at wavelength 220 nm in experiment. To overcome the disadvantages in single-wavelength or double-wavalengths spectrophotometry, the absorbances at the wavelength that covered by the absorption peak are introduced into the construction of the model and to avoid the increase of the model complexification resulted by the introduction of more wavelengths, we run the principal components analysis on the original absorbances data. The data with dimensions compressed from 107 down to 4 after process construct the absorbance model using locally weighted linear regression. Good performance were achieved in both training samples set and test samples set using this model and it was able to deal with the non-linear relation between the absorbance and concentration thus raised the upper range limit concentrations of nitrate nitrogen up to hundreds mg·L-1 from 4 mg·L-1 defined in the standard method. Meanwhile the principle and procedure of this analytical method are suitable for the absorbance model construction of other solutions..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1179 (2017)
Spectroscopic Characteristics of Dissolved Organic Matter from Top Soils on SongHuaba Reservoir in Kunmimg
LI Shuai-dong, ZHANG Ming-li, YANG Hao, LIU Da-qing, YU Li-yan, HUANG Tao, and HUANG Chang-chun
Single spectral technology can not comprehensively reflect structural features and sources of dissolved organic matter (DOM), therefore, in this study ultraviolet-visible (UV-Vis) and the three-dimensional excitation emission matrix fluorescence (3D-EEM) spectroscopy is applied to investigate the structure and origin oSingle spectral technology can not comprehensively reflect structural features and sources of dissolved organic matter (DOM), therefore, in this study ultraviolet-visible (UV-Vis) and the three-dimensional excitation emission matrix fluorescence (3D-EEM) spectroscopy is applied to investigate the structure and origin of dissolved organic matters (DOM) from top soils on SongHuaba reservoir in Kunming. The results showed that the characters of all samples UV-visible spectra were similar. The ultraviolet absorbance of DOM samples decreased gradually with the wavelength increasing. There was an obvious shoulder absorption peak in the 250～280 nm band. The parameters of A250/A365 (absorbance at 250 to 365 nm) ranged from 2.59 to 5.21, which were illustrated that soil DOMs were composed of fulvic acid or humic acid with higher molecular weight. SUVA254 (the specific UV absorbance at 254 nm) and SUVA260 (the specific UV absorbance at 260 nm) were 1.19～3.00 and 1.15～2.89, which showed significant correlation, indicating that soil DOMs had a higher degree of humification and more hydrophilic components in this reservoir. The 3D-EEM spectrum revealed that all DOM samples had three special peaks, which were UV fulvic-like fluorescence, visible fulvic-like fluorescence and humic-like fluorescence, but protein-like fluorescence was not special. As a whole, the fluorescence index (FI) was closed to 1.4, which suggested that the soil DOMs in SongHuaba revesior were main from the external import. Autochthonous index (BIX) was less than 1, which suggested that the soil DOMs were affected by human activities and had low inherent character and bioavailability. These results serve to provide a theoretical basis for the further study of the DOMs effect on the migration and transformation of organic or heavy metal contaminants..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1183 (2017)
The Composition, Structure and Bioavailability of Dissolved Organic Nitrogen (DON) in the Water-Land Interface from Erhai Lake: A Case Study in Yongan Revier
LI Yan-ping, WANG Sheng-rui, ZHAO Hai-chao, ZHANG Li, and ZHANG Rui
The composition, structure and bioavailability characteristics of dissolved organic nitrogen (DON) in the water-land interface of Erhai Lake were studied by using fluorescence and UV-vis absorbance. Moreover, the effect on water quality was also discussed. Results showed that: (1) The DON concentration of the water-lanThe composition, structure and bioavailability characteristics of dissolved organic nitrogen (DON) in the water-land interface of Erhai Lake were studied by using fluorescence and UV-vis absorbance. Moreover, the effect on water quality was also discussed. Results showed that: (1) The DON concentration of the water-land interface from Erhai Lake via Yongan River was between 0.25 and 1.39 mg·L-1, and the DON concentration were relatively high by summer and autumn from the inflow river input into the Erhai Lake. The loading of DON into the Erhai Lake by Yongan River between 0.48 and 2.34 t, and it was relatively high in summer, suggesting that the potential risk for impact on the water quality of Erhai Lake was relatively large by the inflow river into the Erhai Lake, especially in the summer. (2) The DON mainly comprised humic-like substances in the water-land interface from the Yongan river flow into the Erhai Lake, showing the decrease by the microbial degradation with 15.27%, however, aromatic proteins-like and dissolved metabolites of the microorganisms were accumulated by 42.00% and 20.68%, respectively to some extent. In addition, the humification degree of DON was gradually decreased by 14.97% via Yongan River into Erhai Lake. Moreover, the substitution groups in the aromatic rings of DON showed that the transformation of mainly contained aliphatic chains to carbonyl, carboxyl, hydroxyl and esters from inflow river into Erhai Lake, particularly in the summer; (3) The composition characteristic parameters of DON (P(Ⅲ+Ⅴ, n)/P(Ⅰ+Ⅱ, n), A253/A203) was positively correlated with the contents of the different nitrogen (N) forms (R2=0.64～0.74, p<0.1, p<0.05) in the water-land interface from Erhai Lake via Yongan river, that was, the structure affect their bioavailability; the different structural characteristic parameters of DON in the water-land interface from Erhai Lake had a significant positive correlation with water quality(R=0.82～0.96, p<0.05, p<0.01), indicating that the composition, structure and bioavailability of DON had contributed to the water pollution in the water-land interface from the Yongan river input into the Erhai lake, especially being greatly affected by the terrestrial pollution such as human activity in summer. Therefore, the change of composition and structure of DON (such as P(Ⅲ+Ⅴ, n)/P(Ⅰ+Ⅱ, n), A253/A203) in the water-land interface from the Yongan river into lake could reflect the condition of the water quality of Erhai Lake to some extent..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1189 (2017)
Studies on the Ionic Liquid-Assisted Hydrothermal Synthesis of Zn2SnO4
WANG Zhen-xing, XUE Juan-qin, and LI Di
Zinc stannate was prepared with ionic liquid-assisted hydrothermal method. The effect of pH value, hydrothermal time and temperature on the crystal structure, morphology and photocatalytic activity had been investigated in detail. The crystal structure, degree of crystallinity and phase purity of the zinc stannate wereZinc stannate was prepared with ionic liquid-assisted hydrothermal method. The effect of pH value, hydrothermal time and temperature on the crystal structure, morphology and photocatalytic activity had been investigated in detail. The crystal structure, degree of crystallinity and phase purity of the zinc stannate were characterized with X-ray diffractions (XRD). Transmission electron microscopy (TEM) is used to analyze the morphology of the prepared zinc stannate. The photocatalytic activity of the samples was evaluated using degradation of methylene blue under ultraviolet light irradiation. The results indicated that the Zn2SnO4 sample prepared at pH 9, 220 ℃ and 32 h showed the highest activity for photocatalytic degradation of methylene blue. Research on the photocatalytic mechanism of degradation of methylene blue with Zn2SnO4 suggested that the difference in photocatalytic activities of the samples was mainly attributed to defects which can act as recombination centers for photoinduced electrons and holes, reducing the total photocatalytic activity; OH· radicals were the dominant photooxidants..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1198 (2017)
Study on the Interaction of Cefazolin and Ceftriaxone with Human Serum Albumin with Multi-Spectroscopic and Docking Methods
WANG Yi-run, HUANG Fang, and LIU Ying
Cefazolin (CFZ) is the first generation of β-lactam semi-synthetic cephalosporin and which are mainly used to treat Gram positive and negative bacteria. Ceftriaxone (CRO) belongs to the third generation of β-lactam broad-spectrum antibiotic and are particularly useful in treating the disease caused by sensitive bacteriCefazolin (CFZ) is the first generation of β-lactam semi-synthetic cephalosporin and which are mainly used to treat Gram positive and negative bacteria. Ceftriaxone (CRO) belongs to the third generation of β-lactam broad-spectrum antibiotic and are particularly useful in treating the disease caused by sensitive bacteria and post-surgery infection prevention. Human serum albumin (HSA) is the most abundant protein in plasma and can bind with a variety of endogenous and exogenous compounds reversibly, which is playing a role in storage and transport. Therefore, detailed investigating the interaction of CFZ and CRO with HSA are very important to understand the pharmacokinetic behavior of the CFZ and CRO. The interaction between CFZ and CRO with HSA were investigated with fluorescence spectroscopy, three-dimensional fluorescence spectroscopy, circular dichroism (CD) and molecular docking and so on under imitated physiological conditions. The results showed that CFZ and CRO could interact with HSA to form complex at 298 and 310 K, which led to quench the intrinsic fluorescence of HSA via static quenching. After correcting the binding parameters, the Stern-Volmer quenching constants (KSV) and binding constants (Ka) of HSA-CFZ and HSA-CRO system inversely correlated with temperatures, and there was one binding site between HSA-CFZ or HSA-CRO system. Based on the Fster’s theory of non-radiation energy transfer, the specific binding distance between HSA-CFZ or HSA-CRO system was 2.41 or 1.40 nm, respectively. Hill’s coefficients (nH<1) proved that a negative cooperativity was found when CFZ or CRO bound to HSA. The thermodynamic parameters (ΔH(HSA-CFZ)=-22.67 kJ·mol-1, ΔH(HSA-CRO)=-39.56 kJ·mol-1, ΔS(HSA-CFZ)=-4.90 J·mol-1·K-1, ΔS(HSA-CRO)=-37.28 J·mol-1·K-1) demonstrated that CFZ and CRO can spontaneously bind with HSA through hydrogen bonds and van der Waals forces. Three-dimensional fluorescence spectroscopy and circular dichroism (CD) showed that CFZ and CRO could change the micro-environment and conformation of HSA. The results of molecular docking revealed that CFZ and CRO were located in Sudlow’s site Ⅰ of HSA proven bycompetitive binding experiments. This study will be helpful to understand the mechanism which affects the conformation and function of HSA with CFZ and CRO in biological processes..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1205 (2017)
Spectral Study on the Interaction between Ionic Liquid and Fleroxacin
JIANG Tao, ZHANG Jing, ZHAO Wen-yan, ZHANG Chun-ling, and JIA Rui-mei
Ionic liquid can effectively extract quinolones medicines from aqueous phase. In order to explore the extraction mechanism, the interaction between ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate (［C6mim］PF6) and fleroxacin (FLX) were studied by using fluorescence, UV-VIS absorption and infrared spectrometIonic liquid can effectively extract quinolones medicines from aqueous phase. In order to explore the extraction mechanism, the interaction between ionic liquid 1-hexyl-3-methylimidazolium hexafluorophosphate (［C6mim］PF6) and fleroxacin (FLX) were studied by using fluorescence, UV-VIS absorption and infrared spectrometry. With the increasing addition of ［C6mim］PF6, inerratic fluorescence quenching of FLX solution could be observed from fluorescence spectra. Stern-Volmer constant had negative correlation with temperature. Besides, the addition of ［C6mim］PF6 caused a decrease and red-shift of absorption peak in UV-VIS absorption spectra of FLX, which indicated the fluorescence quenching of FLX by ［C6mim］PF6 was due to the formation of ［C6mim］PF6-FLX complex in the ground state through static quenching procedure. Apparent affinity binding constants Ka of interaction between ［C6mim］PF6 and FLX were 130.0, 198.3, 170.6 L·mol-1 at 15, 25, 35 ℃, respectively. Calculating of thermodynamics parameters, ΔG<0, ΔS＞0, ΔH＞0, demonstrated extraction was a spontaneous process, and hydrophobic interaction probably was the major driving force of extraction. ［C6mim］PF6 could orderly distribute in water with the hydrophilic imidazole ring pointing out to the aqueous phase and the hydrophobic alkyl chains together arranging into hydrophobic cavities. In these hydrophobic cavities, the H of —CH— adjacent to N of imidazole rings is a potential H-bond donor, and intensive π electrons in FLX could act as H-bond acceptor, so the FLX entered the hydrophobic cavities of ［C6mim］PF6 due to the interaction of —CH…π type bonds between —CH of ［C6mim］+ and π electrons included in FLX. Furthermore, based on infrared spectra, it suggested that the hydrophobic interaction might be the result of FLX replacing the H2O molecular combined with PF-6 through the hydrogen bonding interaction between PF-6 and —COOH groups of FLX..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1211 (2017)
Deep Ultraviolet Supercontinuum Study in the Highly Nonlinear Photonic Crystal Fiber
YANG Jian-ju, HAN Ying, WANG Wei, ZHOU Gui-yao, ZHAO Xing-tao, HOU Lan-tian, QU Yu-wei, and NIU Jing-xia
Photonic crystal fiber is a good nonlinear medium which plays an important role in generating supercontinuum. Deep ultraviolet supercontinuum light sources in many applications have urgent needs, but due to the influence of experimental conditions and fiber parameters, using highly nonlinear photonic crystal fiber prodPhotonic crystal fiber is a good nonlinear medium which plays an important role in generating supercontinuum. Deep ultraviolet supercontinuum light sources in many applications have urgent needs, but due to the influence of experimental conditions and fiber parameters, using highly nonlinear photonic crystal fiber produced deep ultraviolet supercontinuum (<280 nm) has reported less. In this paper, we study the frequency conversion of high nonlinear photonic crystal fiber in the deep ultraviolet region, and analyze its physical mechanism through theoretical and experimental. Photonic crystal fiber with length of 1.45 m and the zero dispersion wavelength of 825 nm made in our lab is pumped by the femtosecond Ti: sapphire laser in the abnormal region and the dependences of deep ultraviolet supercontinuum on the different pump powers and pump wavelengths are investigated. The experiment results show that when the pump wavelength is fixed to 860 nm, the broadening range of deep ultraviolet supercontinuum is gradually broadened with the increase of pump power; when the pump power is fixed to 0.4 W, the cross-phase modulation between the solitons and the dispersive waves can effectively extend the fundamental mode deep ultraviolet supercontinuum into the wavelength of 212 nm. The increase of pump wavelength not only broadens supercontinuum range but also greatly improves the conversion efficiency of deep ultraviolet supercontinuum..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1215 (2017)
Inspection of the Sensory Preference for Table Grape with Visual-Near Infrared Spectroscopy
YUAN Lei-ming, CAI Jian-rong, SUN Li, XU Deng-cheng, and YE Hua
The sensory preference of consumer was influenced by the internal qualities of fruit, which directly determined the tendency of consumer’s purchase. The visual-near infrared spectroscopy was employed to inspect the internal qualities of “kyoho” table grape and the grade of the sensory preference, aiming to provide the The sensory preference of consumer was influenced by the internal qualities of fruit, which directly determined the tendency of consumer’s purchase. The visual-near infrared spectroscopy was employed to inspect the internal qualities of “kyoho” table grape and the grade of the sensory preference, aiming to provide the fruit with superior qualities for consumers. Spectra in diffuse reflection and transmission acquisition mode were comparatively conducted to measure the internal qualities of table grape. Results show that the transmission spectra had a better capacity to characterize the internal information of grape berries, and the partial least square (PLS) model was optimized to measure sugar content (SC) and total acidity (TA) with root mean square error of prediction (RMSEP) of 0.598%brix, 0.048 g·L-1 respectively. Three nonlinear classification methods were comparatively investigated between the sensory preference of customers and the principal component of transmittance spectra of table grape, and the extreme learning machine combined with principal component analysis (PCA-ELM) model obtained the best performance with the classification accuracy of 78.7%. It was concluded that spectra characterized the internal information of fruit could be used to preliminarily grade the sensory preference of consumers, however, the relationship between them requires further study..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1220 (2017)
Autumn Variation Characteristics Analysis of Leaf Spectrum of Several Common Tree Species
WU Jian, PENG Jian, WANG Meng-he, XU Jian-hui, and GU Liu-wan
Leaf growth will change along with time, so species spectral characteristics will be affected. The researches on spectral changing rule of the same tree leaf under the conditions of different time and spectral characteristics of different tree leaves under the condition of the same time can not only provide theoreticalLeaf growth will change along with time, so species spectral characteristics will be affected. The researches on spectral changing rule of the same tree leaf under the conditions of different time and spectral characteristics of different tree leaves under the condition of the same time can not only provide theoretical basis for vegetation leaf spectral change rule along with time, but also are the keys of vegetation information accurate identification with hyperspectral remote sensing. Ten kinds of common tree species in Beijing were selected and leaf spectrum of each tree species in different time was observed by using spectrometer. At the same time, the observed spectrum was dealt with first order differential and typical bands analysis. Then spectrum difference of different tree leaves at the same time were contrasted and spectrum change laws of the same species in different time were analyzed, and the effective bands of species identification by hyperspectral remote sensing under the condition of different time were explored. The results showed that the leaf spectrum of different tree species had significant changes along with time but the changing rules were different, and there were significant differences among different tree species leaves spectrum in the same time, so it proved a theoretical basis for high precision tree species identification. This study aims at providing basic data and theoretical support for tree species identification of hyperspectral remote sensing and the building of leaf spectrum base database..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1225 (2017)
Visualization of the Water Content for Salmon Fish Fillets Based on Hyperspectral Imaging Technique
ZHAN Bai-shao, ZHANG Hai-liang, and YANG Jian-guo
The potential of near-infrared hyperspectral imaging, as a rapid and nondestructive technique with the spectral wavelength range of 899~1 694 nm, was conducted to predict moisture content (MC) in Atlantic salmon fillets. Altogether 100 fish fillets cutting out from different parts of 5 whole fillets were collected for The potential of near-infrared hyperspectral imaging, as a rapid and nondestructive technique with the spectral wavelength range of 899~1 694 nm, was conducted to predict moisture content (MC) in Atlantic salmon fillets. Altogether 100 fish fillets cutting out from different parts of 5 whole fillets were collected for hyperspectral image scanning. Mean spectral data were extracted automatically from the region of interest (ROI) of Atlantic salmon fillet surface. In order to reduce high dimensionality of hyperspectral images, successive projections algorithm (SPA) was performed to select optimal wavelengths for detection of MC in Atlantic salmon fillets. Partial least square (PLS) was carried out for the detection of MC in Atlantic salmon fillets based on spectral. The results showed that SPA-PLS achieved satisfactory result with R2 of 0.913 and 0.904, RMSEP of 0.965% and 1.169% for both calibration and prediction sets respectively. Then SPA-PLS models were built pixel-wise to the hyperspectral images of the prediction samples to produce chemical images for visualizing MC distribution. The results demonstrated that the potential of hyperspectral imaging technique to predict MC distribution in salmon fillets..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1232 (2017)
Emission Spectrum Diagnosis of Argon/Methane/Air Dielectric Barrier Discharge Plasma
SONG Yi, LOU Guo-feng, ZHANG Fan, and YANG Yang
The discharge of methane/air mixture gas had been investigated by using argon as carrier gas under atmospheric pressure for the first time. The characteristics of the discharge and the emission spectra of the plasma were gained to reveal the properties of ignition and combustion of the mixture gas assisted by plasma unThe discharge of methane/air mixture gas had been investigated by using argon as carrier gas under atmospheric pressure for the first time. The characteristics of the discharge and the emission spectra of the plasma were gained to reveal the properties of ignition and combustion of the mixture gas assisted by plasma under lean-burn condition. Based on the parallel-plate electrode radio frequency (13.56 MHz) dielectric barrier discharge plasma generator, the discharge behavior of the gas mixture, with volume fraction of 90% argon and 10% air, was studied by experiments under atmospheric pressure. A stable and uniform discharge was achieved when methane had been added into the mixture gas at stoichiometric ratio (Φ＝1), while the content of argon maintained at 90%. At last, six discharge experiments were made at different level of the equivalent ratio (0.4 to 1.9). To identify the radicals generated during the process, the data of the emission spectrum were recorded by the spectrometer under different discharge conditions. By using a program compiled by the authors for the nitrogen second positive band system simulation, comparison between the experimental and simulated spectra of band (0-2) 380.4 nm, (1-3) 375.4 nm was used to determine the rotational temperature of nitrogen molecules. The rotational temperature is considered as the temperature of discharge gas. Research results show that the discharging gas temperature would reach 1 150 K in the case of 90%argon/10%air; the temperature would rise to 1 390 K when the mixture was added stoichiometric air and methane; in the case of different equivalence ratios, the plasma gas temperature would go up at the range of 70～240 K, against the mixture of 90%Argon/10%air; The existence of some active radicals, such as CH/H/OH/CH2O, and the raise of temperature indicated that plasma chemical reaction occurred and the release of chemical heat..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1237 (2017)
On-Line Measurement of Converter Combustion Flame with Radiation Thermometry and AES
WANG Yong-qing, CHEN Yan-ru, ZHAO Qi, ZHOU Mu-chun, and SHAO Yan-ming
The end-point control of basic oxygen gurnace (BOF) consists of temperature control and element control. The flame of converter can reflect the decarburization rate and operation parameters of converter. The atomic emission spectra of alkali metals such as kalium and sodium exist in the boiler flames, the temperature oThe end-point control of basic oxygen gurnace (BOF) consists of temperature control and element control. The flame of converter can reflect the decarburization rate and operation parameters of converter. The atomic emission spectra of alkali metals such as kalium and sodium exist in the boiler flames, the temperature of flame can be calculated with the spectral line inversion technique. Two-color method, three-color method and two-line method are used to calculate the flame temperature. The characteristic lines are extracted from the fitting baseline and the wavelet ridge line fitting baseline. Characteristic spectral lines are fitted with Gauss function and Lorenz function. The results show that the radiation thermometry is sensitive to the spectral lines, the reasonable band is necessary to measure the flame temperature effectively and accurately. Two-line method is limited by mathematical model of characteristic spectral line, transition probability of spectral line, degenerate degree of energy level, optical thickness of flame. High resolution spectrometer is necessary to measure the converter flame temperature..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1243 (2017)
Comparative Analysis of Several Mineral Elements Contents in Vascular Bundle of Satsuma Mandarin and Ponkan Mandarin Fruit
YAO Shi-xiang, XIE Jiao, and ZENG Kai-fang
Vascular bundle of Citrus fruit is the tissue between citrus albedo and segment epidermis, mediating the nutrients and water transport between flesh and rind. Such vascular bundle is well-known traditional Chinese medicine with multiple curative effects. The present study was performed to analyze the morphology and relVascular bundle of Citrus fruit is the tissue between citrus albedo and segment epidermis, mediating the nutrients and water transport between flesh and rind. Such vascular bundle is well-known traditional Chinese medicine with multiple curative effects. The present study was performed to analyze the morphology and relative water content of the vascular bundle of Citrus fruit, and further the atomic absorption spectrometry was employed to elucidate several mineral elements contents (K, Ca, Mg, Cu, Zn) in vascular bundle of mandarin and Ponkan mandarin fruit. After brief discussion, several conclusions was made as follows: (1) Relative water content of the vascular bundle was (63.57%±1.53%) in Satsuma mandarin, which was much lower than that in Ponkan mandarin (70.25%±0.24%). (2) Content of K, Ca, Mg in vascular bundle was 3 525～6 495, 6 866～9 430, 394～632 mg·kg-1, respectively in terms of dry weight. Concentration of Cu and Zn in the vascular bundle was 1.5～2.3 and 8.5～14.7 mg·kg-1 , respectively in terms of dry weight. (3) Content of K, Ca, Mg, Zn was relatively higher in vascular bundle of Ponkan mandarin than that of Satsuma mandarin. The present results suggested a well correlation between mineral elements contents in vascular bundle and the water content of fruit, contributing to further research of section-drying in Citrus fruits, as well as deep utilization of this promising resource..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1250 (2017)
Quantitative Analysis of Manganese in Low Alloy Steel with Micro-Laser-Induced Breakdown Spectroscopy
WANG Xu-zhao, AO Zhong-qi, GUO Lian-bo, LI Xiang-you, ZENG Xiao-yan, and LU Yong-feng
Manganese in the low alloy steel was analyzed quantitatively using micro-laser-induced breakdown spectroscopy. The spatial resolution of 20 μm and the single pulse limit of detection of 0.10% were obtained. The calibration curve of Mn was established with basic calibration method, with determination coefficient (R2) ofManganese in the low alloy steel was analyzed quantitatively using micro-laser-induced breakdown spectroscopy. The spatial resolution of 20 μm and the single pulse limit of detection of 0.10% were obtained. The calibration curve of Mn was established with basic calibration method, with determination coefficient (R2) of 0.97. The average relative error of Mn concentration prediction on 7 samples is 12.91%, and the root-mean-square error of cross-validation (RMSECV) is 0.11%. The R2 reaches 0.99 when using internal calibration method, as well as the average relative error of Mn concentration prediction on 7 samples and RMSECV were decreased to 7.25% and 0.07%, respectively. These results show that MicroLIBS technique is an effective approach for material surfaces quantitative microanalysis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1254 (2017)
Study on the Interferences and Direct Determination of Sc in Metallurgical Tails with Inductively Coupled Plasma Mass Spectrometry
LI Jian-ting, ZHANG Yi-ming, DU Mei, HAO Qian, and LI Jian-qiang
After the mineral dressing of iron ore from Bayan Obo ore, the content of scandium is up to 0.05% in tailings, which make it very valuable for utilization. A method for determine the trace scandium in the tailings and Niobium-rich slag with ICP-MS was established in this paper as a simple method with high sensitivity aAfter the mineral dressing of iron ore from Bayan Obo ore, the content of scandium is up to 0.05% in tailings, which make it very valuable for utilization. A method for determine the trace scandium in the tailings and Niobium-rich slag with ICP-MS was established in this paper as a simple method with high sensitivity and accuracy. The working parameters of instrument, sample processing, the interference and eliminating method of coexisting elements were researched systemically. Cesium, thallium and rhodium were selected as the proper internal standard elements to overcome the non-mass spectrometry interference in the procedure of determination. The results of interference investigation showed that some elements in tailings, such as boron, silicon, calcium, zirconium and aluminum, were likely to cause mass spectrometry interference for the determination of scandium, but the concentration of boron was low(<100 μg·mL-1) in the sample that made it have not noticeable interference in the determination. In addition, smaller mass spectrometry interferences made by aluminum and calcium were negligible under the condition of determination. Most noticeably of all, zirconium and silicon mass interferences were more serious, zirconium would form a double charge (90Zr++) ion to interfere the 45Sc+, actually double-charged ions ionization yield was generally not high enough, the interference would be ignored at low concentration, if higher content of zirconium existed, the equation c′=0.021c(Zr)-0.55 was used to correct results. Moreover, high dissociation energy of silicon-oxygen bond and high related isotopic abundance made silicon oxides (28Si17O+, 29Si16O+) have higher stability, therefore the interference in the Bayan Obo ore tailings at measurement condition was more serious, and the formula c″=0.013c(Si)+0.019 can be used to correct results when silicon was not removed in the pretreatment. In summary, the mass spectrometry interferences to the scandium could be eliminated at determination of tailings. Four different sample pretreatment methods were studied and the result showed that sample determination results were consistent with the standard value and the recoveries of standard sample which were between 97%~99%; the silicon and boron mass spectrometry interferences was effectively overcame when used a mixed acids treatment method which contained Hydrochloric acid, hydrofluoric acid and sulfuric acid, besides it could cut down the measurement fluid salinity therefore so then reduced non-mass spectrometry interference. Standard and actual samples were determined and the results showed that the method, established in this paper to direct determination of scandium of the Bayan Obo metallurgical tailings by ICP-MS, was accurate and the relative standard deviation was less than 5%, and the method detection limit was 0.000 1%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1259 (2017)
Analysis of the Main Mineral Composition of Clay Minerals Newly Found in Chuxiong Yunnan
LI Jia-wang, SI Min-zhen, and MAO Huan-xu
To analyze the main mineral composition of the newly found clay minerals in Chuxiong, Yunnan and to determine whether the major minerals are attapulgite clay, this paper conducts tests and researches with infrared spectrum and X-ray fluorescence spectrum on the five kinds of the newly found clay samples. In terms of thTo analyze the main mineral composition of the newly found clay minerals in Chuxiong, Yunnan and to determine whether the major minerals are attapulgite clay, this paper conducts tests and researches with infrared spectrum and X-ray fluorescence spectrum on the five kinds of the newly found clay samples. In terms of the infrared spectrum of five samples, the absorption band at 3 437 cm-1 is the hydroxyl vibration caused by the water of crystallization in attapulgite clay, the absorption band at 3 651 and 3 621 cm-1 is symmetric and asymmetric stretching vibration caused by the hydroxyl of the structure water connected with Mg, Al octahedral on the edge of the hole of attapulgite clay; The absorption peak at 3 699 cm-1 is hydroxyl stretching vibration with internal structure between the tetrahedral and octahedral structure of Mg, Al connected; absorption peak at 1 633 cm-1 is the hydroxyl bending vibration absorption peak of the structure and absorption water, Absorption peak at 1 010 cm-1 is the bond’s (Si—O)characteristic peak of covalent bond (Si—O—Al), Absorption peak at 913 cm-1 is dioctahedral hydroxyl (Al2OH) deformation of the vibration characteristic absorption peak, near the absorption band at 536 and 536 cm-1 is the bond’s (O—Si)characteristic peak of covalent bond (Si—O—Si). The experiments showed that clay minerals of five samples contain higher composition of attapulgite clay, It is found that infrared spectra of three black sample ware compare with spectrum of attapulgite clay similarity in more than 93%, three black samples containing composition of attapulgite clay is very high; the five kinds of attapulgite clay samples may be attapulgite clay minerals. The attapulgite clay formula of attapulgite clay samples is mainly Al5Si8O20(OH2)4·4H2O..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1264 (2017)
An Analysis of Outlier Spectrum: LAMOST J140242.45+092049.8
YANG Hai-feng, CAI Jiang-hui, ZHANG Ji-fu, LUO A-li, ZHAO Xu-jun, and YANG Yu-qing
LAMOST regular survey has successfully observed more than 100, 000 galaxy spectra, which provides important data for mining the precious and rare objects to improve the existing theories. In this paper, the spectrum J140242.45+092049.8 is particularly chosen from LAMOST DR3 by using the outlier mining method based on tLAMOST regular survey has successfully observed more than 100, 000 galaxy spectra, which provides important data for mining the precious and rare objects to improve the existing theories. In this paper, the spectrum J140242.45+092049.8 is particularly chosen from LAMOST DR3 by using the outlier mining method based on the relevant subspaceand intensively discussed these rare characteristics respectively. First of all, the dual-redshift system (absorption system: z1=0.020 95, emission system: z2=0.069 5) are measured and identified by fuzzilyrecognizing the characteristics lines and cross matching the information of the homologous spectrum observed with SDSS. As a whole, the Δz=0.048, which is far greater than the physical interacting threshold (Δz<0.008) provided with Keel, indicating that they are superimposed in the light of sight rather than physical interacting occurring between the foreground galaxy and background one, and the possibility of lens for such “absorption+emission” mode dual-redshift spectrum is illuminated by studying the availableliterature and analyzing the image feature provided with SDSS. For the foreground galaxy (absorption system), the strong Balmer absorption lines and iron lines appeared simultaneouslyin the spectrumimplies that this object will be most likely be E+A galaxy. For the background galaxy (emission system), the characteristic of double peak emission lines is analyzed and the strange relationship between the emission lines is also discussed in the end..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1269 (2017)
Study on Inhomogeneous Correction of Interference Pattern of Spatial Heterodyne Spectrometer
WANG Xin-qiang, ZHANG Li-juan, XIONG Wei, ZHANG Wen-tao, YE Song, and WANG Jie-jun
The intensity distribution is inhomogeneous in the interference pattern received with CCD because of the processing errors and agglutination errors produced during researching and processing of the spatial heterodyne spectrometer, which reduces the accuracy of the transform spectrum. An inhomogeneous correction method The intensity distribution is inhomogeneous in the interference pattern received with CCD because of the processing errors and agglutination errors produced during researching and processing of the spatial heterodyne spectrometer, which reduces the accuracy of the transform spectrum. An inhomogeneous correction method to interference pattern is proposed through analyzing producing mechanism and characteristics of the inhomogeneity existed in interference pattern intensity of spatial heterodyne spectrometer. According to the method, actual interference pattern was decomposed monotonously, piecewise normalized and recombined to solve light intensity distribution function; then the transform spectrum was convolved with Fourier transform result of the reverse light intensity distribution function to obtain inhomogenous correction spectrum; lastly the inverse Fourier transform was implemented to corrected spectrum to realize inhomogenous correction of interference pattern. The correction method could be used in measured monochromatic interference pattern of near infrared light in spatial heterodyne spectrometer. The results show that the method could effectively improve the homogeneity of interference pattern intensity distribution and inhibit edge frequency signal of transform spectrum. Compared with the simulated ideal spectrum, the noise in 1 571 nm spectrum reduces 40.7% while the noise in 1 572 nm spectrum reduces 24% with signal to noise and accuracy of the spectrum being increased..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1274 (2017)
New Measuring Method of Diffraction Efficiency for Concave Grating Based on Fourier Optics Principle
MA Zhen-yu, QI Xiang-dong, LI Xiao-tian, Bayanheshig, YAO Xue-feng, Jirigalantu, ZHANG Shan-wen, and YU Hai-li
Concave diffraction grating not only possesses the function of dispersion and focusing for the light beam at the same time, but also has the advantages of aberration correction, low stray light, none ghost line existence and high signal-to-noise ratio. It has been received extensive attention in the spectral instrumentConcave diffraction grating not only possesses the function of dispersion and focusing for the light beam at the same time, but also has the advantages of aberration correction, low stray light, none ghost line existence and high signal-to-noise ratio. It has been received extensive attention in the spectral instrument field. As one of the most important performance properties of concave diffraction grating, the measurement level of the diffraction efficiency for concave grating becomes one of the most concerned topics in the spectral instrument industry. Double monochromatic structure is usually adopted to measure the diffraction efficiency for concave grating in the traditional method, but it involves two major problems: the first one is the differences of output bandwidths during measuring standard mirror and the tested grating, and the second one is the overlapping of diffracted spectra and scatter light in the instrument. Therefore, the traditional method which contains above problems influences the measurement accuracy of diffraction efficiency for high performance concave grating. In this paper, a new measuring method of diffraction efficiency based on Fourier Optics principle is proposed. The mathematical model of diffraction efficiency measurement is firstly deduced and then verified with ray tracing and Fourier optics simulation. Aiming at reducing the influence of the moving cube corners tilt error, lateral shift error, source instability and maximal moving distance error, we put forward to introducing an assistant detector to collect data together with the main detector. The relative mathematical deduction and simulation have been made under the condition of existence and non-existent of the assistant detector, the result shows that we can effectively control the influences of the above errors and can greatly increase the measurement accuracy of diffraction efficiency when the assistant detector is introduced in the light path. Compared with the traditional double monochromatic structure, our method not only solve the problem mentioned above, but also has the advantages of multi-wavelengths measurement in the same time, high luminous flux, high spectral resolution, and high wave-number accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1279 (2017)
Study on the Slitfunction Test Method Based on Hyperspectral Imaging
MAO Jing-hua, WANG Yong-mei, SHI En-tao, ZHANG Zhong-mou, and JIANG Fang
In order to meet the needs of high-precision measurements of atmospheric trace constituents, accurate description the slitfunction of the detector for atmosperic element measurements is required. Considering the characteristic of large field, wide wavelength range, high spatial and spectral resolution, a slitfunction mIn order to meet the needs of high-precision measurements of atmospheric trace constituents, accurate description the slitfunction of the detector for atmosperic element measurements is required. Considering the characteristic of large field, wide wavelength range, high spatial and spectral resolution, a slitfunction measurement stimulus has been developed. Firstly the theory of slitfunction measurement was supplied. The slitfunction measurement can output high-resolution and wide spectrum and the slit function of the detector for atmosperic element measurements was tested by building an experimental device, The mathematical expression was offered accurately, and the results were analyzed. The results show that: the spectral resolution is about 0.423~0.597 nm of the detector for hyperspectral atmospheric element measurements, and the slitfunction approximating Gaussian distribution. Since the large field of the detector for hyperspectral imaging instrument, a phenomenon of smiling was appealed. This result led to the spectral resolution in the edge of the field slightly below that in the center of the field. For accurate and complete measurement of the slitfunction an echelle monochromator has been developed, which offers a number of high-resolution spectral lines, that can be used to spectral calibration..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1286 (2017)
Research on the Tuning Instantaneous Linewidth Measurement Method of Lasers Based on Time-Varying Power Spectrum
AN Ying, HUANG Xiao-hong, LIU Jing-wang, and LIU Ting-ting
Linewidth measurement of semiconductor laser always uses the heterodyne technology and the linewidth is confirmed with the power spectral density function of the beat signal. According this method, linewidth depends on the power spectral density function confirmed with Fourier transform, but the power spectral density Linewidth measurement of semiconductor laser always uses the heterodyne technology and the linewidth is confirmed with the power spectral density function of the beat signal. According this method, linewidth depends on the power spectral density function confirmed with Fourier transform, but the power spectral density function only defining for the wide-sense stationary signals can not apply to the unstable signals such as the beat signals. Fourier transform is a global transformation losing temporal information, so the dynamic or instantaneous linewidth getting through the power spectral density function is a stable value or a dynamic point in a period of time but not a instantaneous one. In order to contain the instantaneous linewidth of the semiconductor laser in the tuning process, the coherent and the incoherent measuring methods based on the time-varying power spectrum is proposed. The instantaneous linewidth measuring method based on time varying power spectrum has two ways according the time delay, the tuning instantaneous linewidth can be learned by building time varying power spectrum of the beat signals or the laser through doing time-frequency analysis to the beat signals. When doing time-frequency analysis, the beat signals must be decomposed to several mono-component signals firstly because the beat signals are typical non-stationary multi-component signals, and only when the signal is a mono-component signal, has the instantaneous frequency a clear and justifiable physical interpretation. However, the precision of decomposition algorithms is affected seriously by a main slow-varying tendency which changes as a sine or a frequency-modulated wave superimposing the beat signals, and the trend is so legible that it can be obtained in advance, so we propose the Tendency Local Mean Decomposition (TLMD) algorithm combining trend pre-extraction and Local Mean Decomposition (LMD) method which brings more excellence to decompose the beat signals. The time-varying power spectrums of the beat signal and the laser by using the product functions come from decomposition have been built, and the instantaneous linewidth of the distributed feedback semiconductor laser tuned by a sawtooth wave current of 50~51 and 50~100 mA has been obtained finally..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1291 (2017)
Determination of Active Ingredient in Emamectin Benzoate Formulation by Data Fusion Strategy Based on Near/Mid Infrared Spectra and Competitive Adaptive Reweighted Sampling
HU Jing, TANG Guo, DENG Hai-yan, and XIONG Yan-mei
Rapid determination of pesticide active ingredient has been a trend in pesticide quality control. In this paper, we aimed to use data fusion strategy to develop a rapid and reliable method to determine the active ingredient in the emamectin benzoate formulation by fusing the information of NIR and MIR. Data fusion straRapid determination of pesticide active ingredient has been a trend in pesticide quality control. In this paper, we aimed to use data fusion strategy to develop a rapid and reliable method to determine the active ingredient in the emamectin benzoate formulation by fusing the information of NIR and MIR. Data fusion strategy combined with partial least squares (PLS) regression was applied. Competitive adaptive reweighted sampling was engaged to investigate effective variables in the PLS regression. Compared with the models established by independent NIR or MIR, there was a significant improvement provided by data fusion strategy, which benefited from the synergistic effect of complementary information obtained from NIR and MIR spectra. In the meantime, CARS was proved to be an effective variable selection technique in the modeling process that makes the model simpler and more efficient. The results in this work showed that data fusion is an effective modeling strategy that improves the model performance by utilizing more information from different sources. The feasibility of data fusion strategy can obtain better results in determination of low concentration samples (0.1%～1.0%), and data fusion of NIR and MIR spectra combined with a variable selection algorithm could be a promising strategy to determine the active ingredient in commercial pesticide formulation. Eventually, a data fusion method based on near infrared (NIR) spectra and mid infrared (MIR) spectra for determination the active ingredient of emamectin benzoate in the commercial formulation was developed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1297 (2017)
The Calibration Research of DOAS Based on Spectral Optical Density
LIU Zi-long, SUN Li-qun, GUO Yin, YANG Huai-dong, DING Wu-wen, and ZHANG Qiao-xiang
DOAS (differential optical absorption spectroscopy) is an important gas measurement system based on the Lambert-Beer law especially for the trace gas measurement. The measurement key of DOAS is the calibration of the measurement limit. The traditional calibration method is using standard gas. But the concentration valuDOAS (differential optical absorption spectroscopy) is an important gas measurement system based on the Lambert-Beer law especially for the trace gas measurement. The measurement key of DOAS is the calibration of the measurement limit. The traditional calibration method is using standard gas. But the concentration value of standard gas has a large measurement uncertainty which can be large than 10% at ppt. This uncertainty is large than the corresponding specification of instruments which are calibrated. So this traditional method is invalid. A new calibration method is given which is based on spectral optical density. The relationship between measurement limit and optical density can be established using Lambert-Beer law. The optical density as a physical quantity can be measured in 10-6 or more precisely, so the corresponding measurement limit can also be calibrated in ppb or ppt. Firstly, the kinds of optical densities and the total optical density of the measurement system which be calibrated should be analyzed and calculated according to the optical structure (or optical design diagram) of the system. This step is the key of this method because the types of the standard optical densities which are necessary for the measurement of the standard optical density film on the optical density standard equipment. Meanwhile, the optical structure should be understood in order to achieve this calculation. The optical structure include the optical path, every optic cell specification, sphere aberration, astimigation distribution, etc. Secondly, the standard optical density film should be filled in the optical path of the measurement system and the corresponding optical density value is measured. Especially, the optical density film must be filled in the proper station which is confirmed at the step 1 when calculate the different type of the optical density. The error station would make large measurement error which would make large effect into the end data. Then the two above optical density can be compared and the difference of the two value can be considered as the measurement limit. This method is based on the optical measurement without the standard gas. The evaluation error sources only are the measurement error of optical density and the alignment error of the optical structure of the calibrated system. So the calibration of the measurement system can be achieved on small uncertainty, and the measurement limit can be more precise. This method is applied on an open path DOAS and the corresponding experiment data are given..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1302 (2017)
A Probe into the Contents and Spatial Distribution Characteristics of Available Heavy Metals in the Soil of Shell Ridge Island of Yellow River Delta with ICP-OES Method
YANG Hong-jun, SUN Jing-kuan, SONG Ai-yun, QU Fan-zhu, DONG Lin-shui, and FU Zhan-yong
With the application of ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry), available heavy metals (i.e. As, Cd, Cu, Fe, Hg, Mn, Pb, Se, Zn) in the soil of Shell Ridge Island of Yellow River Delta are rapidly determined. The spatial distribution characteristics in the soil of Shell Ridge Island are studWith the application of ICP-OES (Inductively Coupled Plasma-Optical Emission Spectrometry), available heavy metals (i.e. As, Cd, Cu, Fe, Hg, Mn, Pb, Se, Zn) in the soil of Shell Ridge Island of Yellow River Delta are rapidly determined. The spatial distribution characteristics in the soil of Shell Ridge Island are studied, and the distribution rules and influence factors of available heavy metals in soil are analyzed. As indicated in the conclusion, for the contents of nine available heavy metals in the soil samples from Shell Ridge Island of Yellow River Delta, all elements, except for Cadmium (Cd) and Mercury (Hg), fall far below the level 1 background content as specified in the National Environmental Quality Standard for Soils. In this sense, the overall soil of Shell Ridge Island is at clean level. As indicated in the horizontal distribution, due to more human disturbances at the back side of sea and less seawater leaching, the contents of seven available heavy metals (As, Cd, Cu, Fe, Mn, Pb, Zn) are significantly higher than that at the seaward side, and there are significant variations (p≤0.05). As indicated in the analysis of longitudinal soil profile, due to the influences of soil mechanical composition, artificial sand borrowing, terrain and water flow direction, the average concentration value of available heavy metals rise with the increased proportion of soil particles (particle size <0.5 mm) in the profile sample whereas declines with the increased proportion of soil particles (particle size >0.5 mm). There is a downward movement trend of the heavy metals in the soil of Shell Ridge Island, and the maximum value of most available heavy metal contents are located at every layer under the surface layer. However, there are no obvious changes in the overall contents of heavy metals in every layer. Such heavy metals as As, Cd, Cu, Fe, Pb and Zn in the soil of Shell Ridge Island may roughly have the same source, yet different from the source of Hg, Mn and Se. Synoptically speaking, the soil environment in the Shell Ridge Island of Yellow River Delta is not subject to obvious external pollution, while the available heavy metals in the soil of Shell Ridge Island mainly come from the parent material filter feeding bivalve for concentration of heavy metals in seawater, soil particles for the absorption of heavy metals in the environment during weathering process and the migration & transformation of heavy metal pollutants from external industrial regions..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1307 (2017)
XRD Investigation of a Natural Oligoclase at Pressure Up to 27 GPa
DU Jian-guo, MA Yan-zhang, ZHU Hong-yang, XIE Chao, HOU Dong-bin, LI Ying, and SUN Feng-xia
The volume compressibility of natural oligoclase (Na0.86K0.02Ca0.12Mg0.01(Fe0.01Al1.12Si2.87O8)) was investigated by in situ powder synchrotron X-ray diffraction (XRD) methods at pressure up to 27 GPa, and the equations of state (EoS) of the oligoclase were obtained. The experimental data indicate that the oligoclase sThe volume compressibility of natural oligoclase (Na0.86K0.02Ca0.12Mg0.01(Fe0.01Al1.12Si2.87O8)) was investigated by in situ powder synchrotron X-ray diffraction (XRD) methods at pressure up to 27 GPa, and the equations of state (EoS) of the oligoclase were obtained. The experimental data indicate that the oligoclase specimen underwent triclinic to monoclinic phase transition (P1 to C2) at about 3.5 GPa and a further phase transition from C2 to C2/m in monoclinic symmetry at about 10 GPa with increasing pressure. The bulk modulus of the triclinic phase was calculated to be K0=73.8 GPa, and those of monoclinic phases with C2 symmetry and C2/m symmetry to be K(C2)=124 GPa and K(C2/m)=272 GPa, respectively. The stiffness of the T-O-T angle, the strength of the M-O bond and bending of Si-O-Al angle are as a function of the chemical compositions of feldspars. The substitution of mingled ions for main ions in the crystal structure of the oligoclase modified T-O-T angle and the strength of the M-O bonds, resulting in variation of high pressure behavior of the oligoclase. Unit cell compression of triclinic phase oligoclase is obviously anisotropic. The results indicate that oligoclase may probably contribute to the deep recycle of alkali and alkaline-earth elements in the cool subduction zone..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1314 (2017)
Electron Paramagnetic Resonance (EPR) Studies on Free Radical Scavenging Capacity of EGB and EGB Cigarette
JIANG Guo-bin, XU Li, CAO Fu-liang, LI Guo-zheng, and LEI Meng
Free radicals exist both in human body and cigarette smoke, in the forms of many species, i.e. superoxide radical (O-·2), hydroxyl radical (HO·), alkyl radical (R·), alkoxyl radical (RO·) or alkyl peroxyl radical (ROO·), there is no doubt of their pathophysioligical reaction and oxidative damagFree radicals exist both in human body and cigarette smoke, in the forms of many species, i.e. superoxide radical (O-·2), hydroxyl radical (HO·), alkyl radical (R·), alkoxyl radical (RO·) or alkyl peroxyl radical (ROO·), there is no doubt of their pathophysioligical reaction and oxidative damage. Electron paramagnetic resonance (EPR) in conjunction with spin trapping technique is a selected method for free radical detection and quantification. Ginkgo biloba leaves extract (EGB), a phytomedicine mainly composed of flavonoids, terpenoids and proanthocyanidins, is potential in free radical scavenging and antioxidant. In current paper, the scavenging effect against chemical/biological system radical (DPPH, HO·, O-·2) and cigarette smoke radical (gas-phase and particulate-phase radical) for EGB and EGB cigarette have been studied using EPR method, respectively. Several selected flavonoids (Quercetin, Rutin) and Proanthocyanidin also have been assayed and compared. The results show that EGB is managed to scavenging free radical originated by chemical/biological system and cigarette smoke. Although inhibitory capacity is weaker than flavonoids and proanthocyanidin, EGB is obtained easily through extraction and can be developed to natural antioxidant and free radical scavenger in food and tobacco. EPR is a reliable tool in free radical scavenging duing to its good sensitivity and high stability. The spin trap DEPMPO exhibits superiority in trapping superoxide radical and PBN is more efficient in trapping smoke gas-phase radical than DMPO. The mechanism of EGB scavenging free radical has been discussed, multiple phenolic hydroxyl groups are the main reason..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1322 (2017)
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 37, Issue 4, 1 (2017)
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