Journals >Spectroscopy and Spectral Analysis
Contents
2012
Volume: 32 Issue 7
63 Article(s)
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Research Article
Characteristics of Extreme Ultraviolet Emission from Tin Plasma Using CO2 Laser for Lithography
WU Tao, WANG Xin-bing, WANG Shao-yi, and LU Pei-xiang
The extreme ultraviolet (EUV) emission characteristics from Sn plasma for lithography produced by a pulse discharge CO2 laser was investigated under different conditions. Extreme ultraviolet spectral measurements were made throughout the wavelength region of 6.5 nm to 16.8 nm using a grazing incidence flat-field spectrThe extreme ultraviolet (EUV) emission characteristics from Sn plasma for lithography produced by a pulse discharge CO2 laser was investigated under different conditions. Extreme ultraviolet spectral measurements were made throughout the wavelength region of 6.5 nm to 16.8 nm using a grazing incidence flat-field spectrograph coupled with an X-ray charge-coupled device camera for detection of time-integrated spectra. The dependence of spectral properties of the EUV emission on pulse duration, incidence pulse energy, and buffer gas pressure was investigated. The results show that the peak of EUV spectra was located at 13.5 nm. The intensity of EUV emission increased with increasing laser energy ranging from 30 mJ to 600 mJ in a nonlinear manner with saturation effect. The critical energy of incident pulse laser for the generation of EUV emission is near 30 mJ in our experiment. The highest conversion efficiency of 1.2% in producing 13.5 nm EUV light with 0.27 nm bandwidth was achieved at pump energy of 425 mJ. The EUV spectra from a plate target produced by laser pulse with full width at half maximum range from 50 ns to 120 ns were recorded and negligible differences in their spectral features noticed even though higher spectral intensity was observed by shorter pulse duration. The 2% in-band EUV intensity with 52 ns pulse duration was 1.6 times higher than that with 120 ns pulse duration due to the increase in laser intensity. It was also found that the detected EUV spectral intensity rapidly decreased with increasing buffer air pressure, and the EUV emission could be totally absorbed at the pressure of 200 Pa, while weak EUV emission could be still detected at the buffer He gas pressure of 7×104 Pa. The experimental results showed that the absorption coefficient of 13.5 nm light at air buffer gas pressure of 100 Pa was 3.0 m-1, while the absorption coefficient was 0.96 m-1 at the same He buffer gas pressure..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1729 (2012)
Studies on the Data Processing Method in Chlorine Measurement by Differential Optical Absorption Spectroscopy Technology
YE Cong-lei, XIE Pin-hua, QIN Min, LI Ang, LING Liu-yi, HU Ren-zhi, and YANG Jing-wen
In this paper, based on Differential Optical Absorption Spectroscopy (DOAS) technique, experimental measurements of chlorine was carried out in the laboratory with a small self-built experimental system. In dealing with the standard cross-section of chlorine, we presented two different methods: triangle filtering and pIn this paper, based on Differential Optical Absorption Spectroscopy (DOAS) technique, experimental measurements of chlorine was carried out in the laboratory with a small self-built experimental system. In dealing with the standard cross-section of chlorine, we presented two different methods: triangle filtering and polynomial fitting. Experiments showed that the concentration of chlorine could be accurately retrieved by the latter one. Simulation results showed that the error of retrieval result by fifth-order polynomial fitting was smaller than by other orders and an actual retrieval example shows that the fitting spectrums were nearly coincident with the measured spectrums with a residual delta(peak to peak) below 5‰; The results measured in different sample pools displayed a high linearity of 0.996 1 by this method. The main sources of errors during the entire experiment were simply analyzed. According to the experimental result above, it is feasible to detect chlorine using DOAS technology by polynomial fitting..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1734 (2012)
Calculating the Stark Broadening of Welding Arc Spectra by Fourier Transform Method
PAN Cheng-gang, HUA Xue-ming, ZHANG Wang, LI Fang, and XIAO Xiao
It’s the most effective and accurate method to calculate the electronic density of plasma by using the Stark width of the plasma spectrum. However, it’s difficult to separate Stark width from the composite spectrum linear produced by several mechanisms. In the present paper, Fourier transform was used to separate the LIt’s the most effective and accurate method to calculate the electronic density of plasma by using the Stark width of the plasma spectrum. However, it’s difficult to separate Stark width from the composite spectrum linear produced by several mechanisms. In the present paper, Fourier transform was used to separate the Lorentz linear from the spectrum observed, thus to get the accurate Stark width. And we calculated the distribution of the TIG welding arc plasma. This method does not need to measure arc temperature accurately, to measure the width of the plasma spectrum broadened by instrument, and has the function to reject the noise data. The results show that, on the axis, the electron density of TIG welding arc decreases with the distance from tungsten increasing, and changes from 1.21×1017 cm-3 to 1.58×1017 cm-3; in the radial, the electron density decreases with the distance from axis increasing, and near the tungsten zone the biggest electronic density is off axis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1739 (2012)
Spectral Analysis of Nitrofurantoin in the Terahertz Frequency Range
KANG Xu-sheng, HOU Di-bo, ZHANG Guang-xin, CHEN Xi-ai, YUE Fei-heng, HUANG Ping-jie, and ZHOU Ze-kui
The present article measured the absorption coefficient spectra and refractive index spectra of nitrofurantoin original drug, which is one kind of nitrofuran drugs, in the terahertz frequency range from 0.2 to 1.8 THz using terahertz time-domain spectroscopy. The results showed that there exist a number of characteristThe present article measured the absorption coefficient spectra and refractive index spectra of nitrofurantoin original drug, which is one kind of nitrofuran drugs, in the terahertz frequency range from 0.2 to 1.8 THz using terahertz time-domain spectroscopy. The results showed that there exist a number of characteristic absorption peaks of nitrofurantoin with different intensity in the range and the absorption coefficient spectra can be used to identify nitrofurantoin. The article also simulated absorption coefficient spectra of nitrofurantoin molecule within 0.2～1.8 THz using density functional theory by Gaussian software, and vibrational modes of some peaks in the experimental absorption coefficient spectra were analyzed and identified. The results show that the experimental absorption peaks at 1.25 and 1.60 THz correspond with the theoretical peaks at 1.30 and 1.67 THz, and these experimental peaks were caused by intramolecular vibrational modes of nitrofurantoin..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1744 (2012)
Application of Near Infrared Spectroscopy Technology (NIRS) in Forage Field
YAN Xu, BAI Shi-qie, YAN Jia-jun, GAN You-min, and DAO Zhi-xue
The majority of nutrients in ruminants and other herbivores come from forages. Forage quality not only affects the growth and production efficiency of livestock, but also determines the final output and quality of livestock products. Forage quality mainly depends on nutrient concentrations and their digestibility, palaThe majority of nutrients in ruminants and other herbivores come from forages. Forage quality not only affects the growth and production efficiency of livestock, but also determines the final output and quality of livestock products. Forage quality mainly depends on nutrient concentrations and their digestibility, palatability and the level of presence of antiquality factors and mycotoxins in forage. Near infrared reflectance spectroscopy(NIRS) has been widely used in many research areas because it is a inexpensive, rapid, simple and nondestructive technique offering the potential for qualitative and quantitative analysis. The present paper briefly introduces the principle and characteristics of NIRS, detailedly expounds the application of NIRS in forage quality. In addition, other applications of near infrared spectroscopy technique in forage are also discussed, including forage breeding, identification of variety and classification by kind. This paper comprehensively reviews the status quo of application of NIRS in forage filed, in order to contribute to promoting development of NIRS in this field in China..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1748 (2012)
Investigation on Remote Measurement of Air Pollution by a Method of Infrared Passive Scanning Imaging
JIAO Yang, XU Liang, GAO Min-guang, FENG Ming-chun, JIN Ling, TONG Jing-jing, and LI Sheng
Passive remote sensing by Fourier-transform infrared (FTIR) spectrometry allows detection of air pollution. However, for the localization of a leak and a complete assessment of the situation in the case of the release of a hazardous cloud, information about the position and the distribution of a cloud is essential. ThePassive remote sensing by Fourier-transform infrared (FTIR) spectrometry allows detection of air pollution. However, for the localization of a leak and a complete assessment of the situation in the case of the release of a hazardous cloud, information about the position and the distribution of a cloud is essential. Therefore, an imaging passive remote sensing system comprising an interferometer, a data acquisition and processing software, scan system, a video system, and a personal computer has been developed. The remote sensing of SF6 was done. The column densities of all directions in which a target compound has been identified may be retrieved by a nonlinear least squares fitting algorithm and algorithm of radiation transfer, and a false color image is displayed. The results were visualized by a video image, overlaid by false color concentration distribution image. The system has a high selectivity, and allows visualization and quantification of pollutant clouds..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1754 (2012)
Spectral Investigation of Atmospheric Pressure Plasma Column
LI Xue-chen, CHANG Yuan-yuan, and XU Long-fei
Atmospheric pressure plasma column has many important applications in plasma stealth for aircraft. In the present paper, a plasma column with a length of 65 cm was generated in argon at atmospheric pressure by using dielectric barrier discharge device with water electrodes in coaxial configurations. The discharge mechaAtmospheric pressure plasma column has many important applications in plasma stealth for aircraft. In the present paper, a plasma column with a length of 65 cm was generated in argon at atmospheric pressure by using dielectric barrier discharge device with water electrodes in coaxial configurations. The discharge mechanism of the plasma column was studied by optical method and the result indicates that a moving layer of light emission propagates in the upstream region. The propagation velocity of the plasma bullet is about 0.6×105 m·s-1 through optical measurement. Spectral intensity ratios as functions of the applied voltage and driving frequency were also investigated by spectroscopic method. The variation in spectral intensity ratio implies a change in the averaged electron energy. Results show that the averaged electron energy increases with the increase in the applied voltage and the driving frequency. These results have significant values for industrial applications of the atmospheric pressure discharge and have extensive application potentials in stealth for military aircraft..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1758 (2012)
Near-Infrared Spectroscopy Analysis of Adenosine and Water in Fermentation Cordyceps Powder and Wavelength Assignment
XU Ning, WEI Xuan, REN Bing, HE Yong, and FENG Lei
Based on near-infrared spectroscopy, four characteristic wavebands 4 277.63~4 3166.20, 4 887.06~4 941.07, 5 056.78～5 172.50 and 5 218.78~5 303.64 cm-1, and two characteristic wavebands 4 902.49~4 817.64 and 4 740.49~4 107.91 cm-1 were chosen to establish the partial least squares (PLS) regression model of water and adeBased on near-infrared spectroscopy, four characteristic wavebands 4 277.63~4 3166.20, 4 887.06~4 941.07, 5 056.78～5 172.50 and 5 218.78~5 303.64 cm-1, and two characteristic wavebands 4 902.49~4 817.64 and 4 740.49~4 107.91 cm-1 were chosen to establish the partial least squares (PLS) regression model of water and adenosine in fermentation cordyceps powder, respectively. The prediction results of water and adenosine contents of the whole spectra PLS model were as follows: correlation coefficients (r) were 0.868 3 and 0.788 2, RMS error predictions (RMSEP) were 0.001 999 and 0.000 134, the remaining prediction deviations (RPD) were 1.974 4 and 1.640 7, respectively. However, using characteristic wavebands modeling can achieve a better performance with r of 0.869 1 and 0.829 0, RMSEP of 0.001 934 and 0.001 250, and RPD of 2.040 7 and 1.847 6 for water and adenosine respectively, and can largely improve calibration speed, providing the theoretical basis for the development of the testing instruments. So choosing the characteristic wavebands in this work to determine the water and adenosine in fermentation cordyceps powder is more effective..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1762 (2012)
Effects of Indocyanine Green on Near-Infrared Optical Properties and Optical Coherence Tomographic Image of Cerebral Blood Vessel in Vivo in Rats
WANG Cui-ping, ZENG Chang-chun, GUAN Xiao-yue, ZHU Zhi-rong, and LIU Song-hao
The scope of this research lies in the effects of indocyanine green (ICG) on the near-infrared optical properties and optical coherence tomographic image of cerebral blood vessel in vivo in rats. The skulls of SD rats were opened under nembutal anesthesia to expose and mark the middle cerebral artery. The reflectance sThe scope of this research lies in the effects of indocyanine green (ICG) on the near-infrared optical properties and optical coherence tomographic image of cerebral blood vessel in vivo in rats. The skulls of SD rats were opened under nembutal anesthesia to expose and mark the middle cerebral artery. The reflectance spectra of middle cerebral artery were monitored by Vis/NIR spectrometer and the optical attenuation coefficients of middle cerebral artery were detected by optical coherence tomography (OCT) when indocyanine green was administrated intravenously through tail veins. It was shown that the reflectance spectra of middle cerebral artery could provide guidance for OCT image, where characteristic changes appeared around 800 nm, an absorption peak of indocyanine green. Additionally, significant difference (p<0.01) was observed between the optical attenuation coefficients of middle cerebral artery with and without indocyanine green, which were 24.692±1.471 and 15.088±1.602, respectively. It was concluded that indocyanine green, as an optical contrast agent to enhance detection of cerebral artery by the reflectance spectra and OCT imaging, has the potential for monitoring and imaging of cerebral blood vessels..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1766 (2012)
Preparation of Fluoridated Hydroxyapatite Coatings on Titanium by Electrolytic Deposition and Its FTIR Characteristics
HUANG Yong, PANG Xiao-feng, LI Gun, YAN Ya-jing, HAN Shu-guang, and ZENG Hong-juan
Fluoridated hydroxyapatite coatings (FHAP) were prepared on titanium substrate by electrochemical deposition technique containing Ca2+, PO3-4, and F－ ions. The deposition was all conducted at a constant current of 0.9 mA for 60 min at 60 ℃. The as-prepared coatings were exa mined by scanning electron microscope (SEM), Fluoridated hydroxyapatite coatings (FHAP) were prepared on titanium substrate by electrochemical deposition technique containing Ca2+, PO3-4, and F－ ions. The deposition was all conducted at a constant current of 0.9 mA for 60 min at 60 ℃. The as-prepared coatings were exa mined by scanning electron microscope (SEM), energy-dispersive Xray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR) and Xray diffraction (XRD) tests. The results indicate that the FHAP cryatals take the morphology of nanoscale-rodlike cone rather than the micron-daisy petal, and the composite coating becomes more compact. The FTIR test indicates that the symmetry of stretching and bending vibration modes of hydroxyl changed, simulated body fluid immersion test proved that the FHAP coating had induced carbonate-apatite formation, indicating that the composite coating possesses excellent biocompatibility..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1771 (2012)
The Study of Transpiration Influence on Plant Infrared Radiation Character
LING Jun, ZHANG Shuan-qin, PAN Jia-liang, LIAN Chang-chun, and YANG Hui
Studying vegetation infrared radiation character is the base of developing infrared camouflage and concealment technology of ground military target. Accurate fusion of target and background can be achieved by simulating formation mechanism of vegetation infrared radiation character. Leaf transpiration is characteristicStudying vegetation infrared radiation character is the base of developing infrared camouflage and concealment technology of ground military target. Accurate fusion of target and background can be achieved by simulating formation mechanism of vegetation infrared radiation character. Leaf transpiration is characteristic physiological mechanism of vegetation and one of the main factors that influence its infrared radiation character. In the present paper, physical model of leaf energy balance is set up. Based on this model the influence of plant transpiration on leaf temperature is analyzed and calculated. The daily periodic variation of transpiration, leaf temperature and infrared radiation character of typical plants such as camphor tree and holly is actually measured with porometer and infrared thermal imaging system. By contrasting plant leaf with dryness leaf, experimental data indicates that plant transpiration can regulate leaf energy balance effectively and control leaf temperature in a reasonable range and suppress deep range variation of leaf infrared radiation character..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1775 (2012)
Study of the Effect of Temperature on the Conformation of Ovotransferrin by Two-Dimensional Infrared Correlation Spectroscopy
REN Guo-dong, GUO Ai-ling, GENG Fang, MA Mei-hu, HUANG Qun, and WU Xiao-fen
The conformation changes of Apo-Ovotransferrin and Holo-Ovotransferrin were studied with the heat treatment 25~95 ℃ by using Fourier transform infrared spectroscopy (FTIR) and two-dimensional correlation spectroscopy analyzer. The results of one-dimensional infrared spectroscopy showed that with the increase in temperaThe conformation changes of Apo-Ovotransferrin and Holo-Ovotransferrin were studied with the heat treatment 25~95 ℃ by using Fourier transform infrared spectroscopy (FTIR) and two-dimensional correlation spectroscopy analyzer. The results of one-dimensional infrared spectroscopy showed that with the increase in temperature, the peak at 3 300 cm-1 of Apo-Ovotransferrin shifted more than that of Holo-Ovotransferrin. The peak at 3 300 cm-1 derived from stretching vibrations of N—H and O—H indicates that iron-binding enhanced the role of hydrogen bonds and resistance to heat. The changing order of the secondary structure of ovotransferrin was determined by analyzing two-dimensional infrared spectra, witch is β-sheet>amideⅡ>—CH2— bending vibration. In addition, it was found that the cross-peaks at 1 652 and 1 688 cm-1 are different in synchronous and asynchronous counter maps by comparing Apo-Ovotransferrin with Holo-Ovotransferrin. It was suggested that the temperature made less impact on the α-helix in Holo-Ovotransferrin than on that in Apo-Ovotransferrin, however, the β-turn in Holo-Ovotransferrin was more sensitive to temperature..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1780 (2012)
Rapid Identification of Softwood and Hardwood by Near Infrared Spectroscopy of Cross-Sectional Surfaces
YANG Zhong, LV Bin, HUANG An-min, LIU Ya-na, and XIE Xu-qin
The feasibility of wood identification of softwood and hardwood by near infrared spectroscopy (NIR) coupled with partial least squares discriminant analysis (PLS-DA) was investigated in the present paper. The near infrared spectra (780～2 500 nm) were collected from wood cross-section from one softwood species (Chinese The feasibility of wood identification of softwood and hardwood by near infrared spectroscopy (NIR) coupled with partial least squares discriminant analysis (PLS-DA) was investigated in the present paper. The near infrared spectra (780～2 500 nm) were collected from wood cross-section from one softwood species (Chinese fir) and one hardwood species (eucalyptus). The results show that: (1) The identification accuracy of the calibration samples predicted by the model based on NIR coupled the PLS-DA was 100%. The correlation coefficient between the NIR predicted category variable value and the true value was 0.990, and the SEC was 0.071; (2) The identification accuracy by the model based on the spectra with 780~1 100 nm wavelengths also was 100%, and the correlation coefficient and SEC were 0.990 and 0.070, respectively; (3) The identification accuracy for the test samples was 100%. It was suggested that NIR can be used to rapidly and accurately identify softwood and hardwood samples. It also provides a new approach to identifying wood species..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1785 (2012)
The Analysis for Silver Iodide Fine Particles of TLC/FTIR Matrix
ZHU Qing, SU Xiao, WU Hai-jun, ZHAI Yan-jun, XIA Jin-ming, Buhebate, XU Yi-zhuang, and WU Jin-guang
In situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the proIn situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the problem, the authors propose to use AgI fine particles as stationary phase of TLC plate. The reasons are as follows: Silver iodide fine particles have no absorbance in an IR region between 4 000 and 800 cm-1, therefore, the interference caused by IR absorption of stationary phase can be removed. Moreover, silver iodide is stable and insolvable in water and organic solvents and thus it will not be destroyed by mobile phase or react with samples during the TLC separation. To improve TLC separation efficiency and quality of FTIR spectra during the TLC/FTIR analysis, the size of AgI particles should be below 500 nm. We used orthogonal design approach to optimize the experimental condition to AgI particles so that the average size of AgI particles is around 100 nm. No absorption of impurity or adsorbed water were observed in FTIR spectrum of the AgI particles the authors used “settlement volatilization method” to prepare TLC plate without using polymeric adhesive that may bring about significant interference in FTIR analysis. Preliminary TLC experiments proved that the TLC plate using AgI fine particles as stationary phase can separate mixtures of rhodamine B and bromophenol blue successfully. Applications of silver iodide fine particles as stationary phase have bright perspective in the development of in-situ TLC/FTIR analysis techniques..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1790 (2012)
Comparative Study on the Performance of Deformable Mirror of NIR Based Human Eye Aberration Correction System
NIU Sai-sai, SHEN Jian-xin, LIANG Chun, ZHANG Yun-hai, and LI Bang-ming
The structure features and spatial characteristics of the two kinds of micro-machined membrane deformable mirrors, OKO 37-element and BMC 140-element, which work in the NIR based human eye aberration correction system, are compared and analyzed. At same time, the principal component analysis was carried out for the infThe structure features and spatial characteristics of the two kinds of micro-machined membrane deformable mirrors, OKO 37-element and BMC 140-element, which work in the NIR based human eye aberration correction system, are compared and analyzed. At same time, the principal component analysis was carried out for the influence function of the mirror, the voltage control model was established and the optimal control mode of deformable mirror can be determined by adjusting the control parameter d. Finally, the simulation experiments for fitting aberration of unit Zernike mode and human eye aberration of Thibos model were carried out. The experiment results show that the capability for fitting the each Zernike mode of BMC 140-element mirror is twice more than the OKO 37-element mirror at least. When correcting the Thibos model human eye aberration whose average RMS error is 0.638λ(λ=0.785 μm), the residual RMS error of BMC mirror is 0.063λ which achieves the diffraction limit (λ/14) of the optical system, but the correction capability of OKO mirror is far less than BMC mirror due to the large cross-linked value between actuators, small density distribution of actuators and some other influencing factors, and the residual wave-front RMS error is 0.168λ. The methodology can also be used for other types of deformable mirror performance evaluation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1795 (2012)
Nondestructive Identification of the Root of Mountain Cultivation Ginseng and Growth Years by Near Infrared Spectroscopy
BU Hai-bo, NIE Li-xing, WANG Dan, DU Hong, WANG Gang-li, and LI Xiang-ri
Mountain cultivation ginseng (MCG) and garden cultivation ginseng (GCG) were identified by near infrared spectroscopy, so were MCG of different growth years. 96 MCG samples of different growth years, including 24 of fifteen years and 72 of ten years, and 177 GCG samples were collected. After the near infrared spectra oMountain cultivation ginseng (MCG) and garden cultivation ginseng (GCG) were identified by near infrared spectroscopy, so were MCG of different growth years. 96 MCG samples of different growth years, including 24 of fifteen years and 72 of ten years, and 177 GCG samples were collected. After the near infrared spectra of these samples were collected, discriminant analysis was used to distinguish MCG and GCG, so was MCG of different years. After the original spectra were pretreated, discriminant analysis models of MCG and GCG, MCG of different growth years were developed respectively with selected principal component numbers in full spectra region. The correct discrimination rate of two groups of model was both 100%. The proposed methods are accurate, fast and nondestructive, and can be applied to the quality control of MCG. It has an important significance for building market image of MCG..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1801 (2012)
Infrared Spectrum Characteristics of Vehicle Body Paint
CHEN Tao, LONG Xian-jun, WEI Lang, GONG Biao, and LI Chun-ming
Two hundred eighty seven samples of vehicle paint were collected, and 940 spectra were obtained by Fourier transform infrared micro spectrometer. The spectral features of varnish, finish layer, and coated layers of different models and different color were analyzed, and the spectra similarities were compared. The resulTwo hundred eighty seven samples of vehicle paint were collected, and 940 spectra were obtained by Fourier transform infrared micro spectrometer. The spectral features of varnish, finish layer, and coated layers of different models and different color were analyzed, and the spectra similarities were compared. The results show that the varnish similarity on the same models with different color is 99.5%, and some similar model with the same manufacturer had high similarity. The finish spectra have remarkable differences with different model and different color, and the similarity degree is under 70%. The coated layer similarity varies between 83.33% and 96.91% among the common lacquer putty, and it ranges between 70.12% and 96.44% among the water-based lacquer putty. The metal components of paint will influence the spectrum characteristics. The spectra of the vehicle paint will change with the usage time..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1806 (2012)
Study on Extracts of Active Substances from Larch Bark by FTIR Spectroscopy
CUI Xiao-xia, ZHANG Xiao-li, TANG Huan-wei, ZHANG Li-ping, XU Chang-hua, and SUN Su-qin
The present study is to compare and analyze extracts of active substances from larch bark using ultrasonic wave quickly and undamagedly via Fourier transform infrared spectroscopy, second derivative IR spectroscopy and two dimensional spectroscopy. In the spectra of active substances from larch bark, there are four maiThe present study is to compare and analyze extracts of active substances from larch bark using ultrasonic wave quickly and undamagedly via Fourier transform infrared spectroscopy, second derivative IR spectroscopy and two dimensional spectroscopy. In the spectra of active substances from larch bark, there are four main components as the structural unit, and (+)-catechin, (-)-epicatechin, gallic acid and vitisinol represented a series of poly polyphenolic compounds. Furthermore the linkage between unit in proanthocyanidins dimmers was confirmed at position C(4)-C(8). Through observing the second derivative IR spectra of active substances from larch bark, the absorption peaks, 1 631, 1 561 and 1 469 cm-1 of active substances moved to the smaller wave number direction, while 1 606, 1 385, 1 285 and 1 157 cm-1 of active substances moved to the bigger wave number direction, and the intensity of characteristic peaks can represent the content of corresponding compound. In the two dimensional spectra, the active substances from larch bark have five automatic peaks in 1 345~1 675 cm-1. The authors developed the new method to analyse and evaluate the active substances from larch bark successfully..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1810 (2012)
Study on Secondary Structural Changes of Protein in the Formation of Microcapsule by FTIR Spectroscopy
SHI Yan, LIU Fan, GE Hui, CHEN Zhi-wei, and ZHENG Wei-wan
The mixture of whey protein and isolated soy protein with maltodextrin as microcapsules wall material was adopted. The secondary structure constitution of these two kinds of proteins in the process of heating and spray drying together with maltodextrin were studied by Fourier transform infrared spectra. The result showThe mixture of whey protein and isolated soy protein with maltodextrin as microcapsules wall material was adopted. The secondary structure constitution of these two kinds of proteins in the process of heating and spray drying together with maltodextrin were studied by Fourier transform infrared spectra. The result showed that both whey protein and isolated soy protein exhibited differences in the secondary structures. The rate of α-helix in whey protein decreased 1.9% and β-turn content of the protein remains virtually unchanged, β-sheet increased 8.19%, and random coil decreased 7.18%. At the same time the content of α-helix in isolated soy protein decreased 1.64%, the change of β-sheet is not obvious while β-turn increased 10.20% and random coil decreased 9.03%. Meanwhile, the amideⅠbands of these two proteins both shifted to the lower wave number direction, indicating that in the formation process of the microcapsule wall structure there are complex interactions between maltodextrin and proteins, and the hydrogen bonds which comes into existence are comparatively strong. With the help of scanning electron microscope, it was discovered that the surface is more smooth and integrated when the microcapsules wall material contains whey protein, which is high in alpha helix..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1815 (2012)
Study on Characteristics of Laser Ablation in KTP Crystal and Its Influence on the Raman Spectroscopy
HAN Jing-hua, DUAN Tao, FAN Wei-xing, FENG Guo-ying, YANG Li-ming, NIU Rui-hua, YANG Jie, ZHAI Ling-ling, and GUO Chao
The research and development of the KTP crystal with high threshold is of very importance for its application in high-energy laser systems. Ablation characteristics in KTP crystal as well as their influence on the Raman spectroscopy were studied by UV laser with high repetition frequency.The research results show that The research and development of the KTP crystal with high threshold is of very importance for its application in high-energy laser systems. Ablation characteristics in KTP crystal as well as their influence on the Raman spectroscopy were studied by UV laser with high repetition frequency.The research results show that the laser plasma effects are the main reasons for the damage in the KTP crystal. The inverse bremsstrahlung absorption effect can increase the deposition of the laser pulse energy greatly; the ionization effect can make the crystal dislocated completely; shock wave effect can push away the mixture of melted, vaporized and ionized materials and cause cracks in the pit. Through investigation and comparison of the Raman spectroscopy before and after the laser ablation, it was found that the distribution characteristics of Raman peaks are almost the same, suggesting that the basic structures of KTP crystal do not change. But almost all the Raman characteristic peaks’ RIR values have changed and the widths are broadened, which means that the crystalline degree has been decreased. The Raman peaks of TiO6 and PO4 oxygen polyhedron shift to the lower wave number, which indicates that bonding force becomes weaker and the KTP crystal can be damaged easily..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1820 (2012)
SERS Spectroscopy Study of Three Pathogenic Bacteria
SU Yong-bo, SI Min-zhen, ZHANG De-qing, LIU Ren-ming, and LIN Feng-chun
The SERS spectra of staphylococcus aureus, proteus, and Escherichia coli was obtained on colloidal Ag nanoparticles prepared by the microwave method with the portable Raman spectrometer. Staphylococcus aureus have obvious Raman vibrating peak at 725, 1 330 and 1 450 cm-1, proteus have obvious Raman vibrating peaks at 6The SERS spectra of staphylococcus aureus, proteus, and Escherichia coli was obtained on colloidal Ag nanoparticles prepared by the microwave method with the portable Raman spectrometer. Staphylococcus aureus have obvious Raman vibrating peak at 725, 1 330 and 1 450 cm-1, proteus have obvious Raman vibrating peaks at 650, 725, 950, 1 325 and 1 463 cm-1, while E. coli have obvious Raman vibrating peaks at 650, 950, 1 125, 1 242, 1 320 and 1 457 cm-1. Each peak was assigned preliminarily. Not only the position of Raman vibration peaks but also the intensity of the three bacteria is obviously different, so SERS can be used for identification and distinction of E. coli, staphylococcus aureus and proteus..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1825 (2012)
Fast Discrimination of Edible Vegetable Oil Based on Raman Spectroscopy
ZHOU Xiu-jun, DAI Lian-kui, and LI Sheng
A novel method to fast discriminate edible vegetable oils by Raman spectroscopy is presented. The training set is composed of different edible vegetable oils with known classes. Based on their original Raman spectra, baseline correction and normalization were applied to obtain standard spectra. Two characteristic peaksA novel method to fast discriminate edible vegetable oils by Raman spectroscopy is presented. The training set is composed of different edible vegetable oils with known classes. Based on their original Raman spectra, baseline correction and normalization were applied to obtain standard spectra. Two characteristic peaks describing the unsaturated degree of vegetable oil were selected as feature vectors; then the centers of all classes were calculated. For an edible vegetable oil with unknown class, the same pretreatment and feature extraction methods were used. The Euclidian distances between the feature vector of the unknown sample and the center of each class were calculated, and the class of the unknown sample was finally determined by the minimum distance. For 43 edible vegetable oil samples from seven different classes, experimental results show that the clustering effect of each class was more obvious and the class distance was much larger with the new feature extraction method compared with PCA. The above classification model can be applied to discriminate unknown edible vegetable oils rapidly and accurately..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1829 (2012)
Fluorescence Spectrum Monitor for Early Warning of Greenhouse Cucumber Aphis Pests
SUI Yuan-yuan, YU Hai-ye, ZHANG Lei, LUO Han, REN Shun, and ZHAO Guo-gang
The infection and degree of cucumber aphis pests was studied by analyzing chlorophyllfluorescence spectrum in greenhouse. Based on the configuration of the spectrum, characteristic points were established, in which the intensity of waveband F632 was the first characteristic point between healthy and aphis pests leaves.The infection and degree of cucumber aphis pests was studied by analyzing chlorophyllfluorescence spectrum in greenhouse. Based on the configuration of the spectrum, characteristic points were established, in which the intensity of waveband F632 was the first characteristic point between healthy and aphis pests leaves. The second characteristic point was K which was the change rate of spectral curve from waveband F512 to F632. The early warning could be executed on plants depending on these two points. The models of the infection and degrees of aphis pests were established for different wavebands by the least square support vector machine classification method (LSSVMR) radial basis function(RBF). The accuracy rate of classification and prediction of the models was compared by different peaks and valleys value in wavebands. The results indicated that the prediction accuracy of the model established by waveband F632 was the most perfect (96.34%)..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1834 (2012)
A Method for Determination of Trace Naphthalene and Phenanthrene in Water Using Constant-Wavelength Synchronous Fluorescence Spectrometry
SONG Guang-qing, XI Hong-bo, ZHOU Yue-xi, LI Jie, ZHAO Jing-tian, and CUI Jun-hua
In view of synchronous fluorescence possessing the character of good selectivity, high sensitivity, less interference, etc. it can be used for simultaneous determination of multi-component mixtures of polycyclic aromatic hydrocarbons(PAHs). A new method of constant-wavelength synchronous fluorescence spectrometry to deIn view of synchronous fluorescence possessing the character of good selectivity, high sensitivity, less interference, etc. it can be used for simultaneous determination of multi-component mixtures of polycyclic aromatic hydrocarbons(PAHs). A new method of constant-wavelength synchronous fluorescence spectrometry to determine two naphthalene and phenanthrene of PAHs was developed in this study. The effect of different experimental conditions, such as different disolvents for character of fluorescence spectra and the choose of the optimal wavelength difference were studied. Experiment showed that the simultaneous indentification and quantitative determination of the two PAHs when Δλ=100 was chosen. The fluorescence intensity was linearly related to naphthalene and phenanthrene concentration in the range of 0.5～25.0 μg·L-1 with correlation coefficient 0.999 5 and 0.999 7, respectively. The detection limits were all lower than 0.03 μg·L-1, and the relative standard deviations for naphthalene and phenanthrene were 1.19% and 180%(n=7), respectively. Results show that the compounds can be analyzed qualitatively and quantitatively by synchronous fluorescence spectrometry..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1838 (2012)
Research on the Degradation of BaP with Potassium Ferrate Characterized by Fluorescence
CHEN Yu-zhe, HE Qiang, YU Dan-ni, LI Si, and TAN Xue-mei
The degradation of Benzo(a)pyrene (BaP) by potassium ferrate was researched by means of multiple fluorescence spectroscopic methods such as synchronous, time-scan, excitation emission matrix (EEM) and photometry, under the optimal condition. Within the degradation process, the characteristics of the BaP’s concentrationThe degradation of Benzo(a)pyrene (BaP) by potassium ferrate was researched by means of multiple fluorescence spectroscopic methods such as synchronous, time-scan, excitation emission matrix (EEM) and photometry, under the optimal condition. Within the degradation process, the characteristics of the BaP’s concentration at different time-intervals, and the kinetics of the degradation of BaP by potassium ferrate were discussed. From the experimental data, both synchronous and EEM spectra’s results showed that the concentration of BaP was reduced 90% by potassium ferrate within 20 s after degradation, and the reaction process was very slow after 60 s. The degradation kinetic equation, ln(F0/Ft)=0.563 2t+0.171 2, (R2=0.994 2), was obtained through a convenient and fast way combining the time-scan fluorescence data and photometry data, and the photometry included the synchronous photometry and emission photometry. According to the kinetic equation, the degradation of BaP by potassium ferrate was in accord with the order of the first order reaction. So this article could provide a very useful conference for the research on the pollutant degradation by potassium ferrate, especially for the degradation process and the degradation mechanisms..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1842 (2012)
The Investigation of Organic Matter Removal in Water Treatment Plant by EEM Spectra Coupled with Self-Organizing Map
DU Er-deng, GUO Ying-qing, SUN Yue, GAO Nai-yun, and WANG Li-ping
Three-dimensional excitation and emission matrix fluorescence spectra (3D-EEM) has attracted the increasing attention of researchers in water monitoring and water treatment areas. The self-organizing map (SOM) is a kind of non-supervised and self-learning neural network with the feature of high self-stability and noiseThree-dimensional excitation and emission matrix fluorescence spectra (3D-EEM) has attracted the increasing attention of researchers in water monitoring and water treatment areas. The self-organizing map (SOM) is a kind of non-supervised and self-learning neural network with the feature of high self-stability and noise tolerance. In the present paper, SOM technique was employed for the exploratory analysis of EEM spectra of water samples in a water treatment plant. The results showed that EEM spectra could be clustered into three classes, corresponding to tryptophan-like protein substances, tyrosine-like protein substances, and UV fulvic-like substances. The three components could be effectively removed during the whole water treatment process with the high removal of 84.6% (tyrosine-like), 79.9% (tryptophan-like), and 69.1% (UV fulvic-like). The results show that SOM technique can be used as an effective tool for EEM spectra analysis, which is helpful for the optimization of water treatment process parameters, the improvement of process performance, and the operation of water treatment plant..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1846 (2012)
Research on Transient Temperature Detection by Spectrum Function Variation of Speckle Pattern Interferometry
WU Jin-hui, YANG Rui-feng, and WANG Gao
To improve the accuracy of the transient temperature detection system, transient temperature inversion processing algorithms was proposed based on spectrum analysis of speckle pattern interferometry. The interference fringes were formed by speckle interferometry in the system, and due to transient temperature changes tTo improve the accuracy of the transient temperature detection system, transient temperature inversion processing algorithms was proposed based on spectrum analysis of speckle pattern interferometry. The interference fringes were formed by speckle interferometry in the system, and due to transient temperature changes that cause the material strain, the speckle interference pattern changes. The interference fringes on the measured surface were obtained by the area array CCD collection before and after deformation. The corresponding spectrum density function will change with the changes in the transient temperature, and the amplitude changes of center wavelength were inverted by the speckle pattern interferometry. Through detecting and calculating the ratio of the amplitude of the center wavelength, the transient temperature can be obtained by spectrum analysis. In the analysis and calculation for the function of transient temperature and material strain, material strain and interference fringes, the amplitude and phase function of the transient temperature change and interference fringes were derived, providing the necessary conditions for detecting spectral density function temperature. The experiment used 660 nm laser diode and SI6600 type area CCD detector. By extracting the offset of the center wavelength from the spectrum distribution function, the calculation and calibration data were compared to the data obtained with the traditional method of interference temperature detection, and the result showed that the detection accuracy can achieve 0.3%. Compared to traditional direct detection of interference fringes changes, the accuracy improved nearly three times by the method..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1852 (2012)
Effects of Different Fertilization Treatments on Soil Humic Acid Structure Characteristics
ZHAO Nan, and LV Yi-zhong
The present article used soil humic acid as research object to study effects on the structure characteristics of soil humic acid under the condition of applying cake fertilizer, green manure, straw fertilizer with the same contents of nitrogen and phosphorus. It used element analysis, micro infrared, and solid 13C-NMR The present article used soil humic acid as research object to study effects on the structure characteristics of soil humic acid under the condition of applying cake fertilizer, green manure, straw fertilizer with the same contents of nitrogen and phosphorus. It used element analysis, micro infrared, and solid 13C-NMR for structure analysis, the results indicated that: The chemical composition and structure characteristics of humic acids were similar, but they also had many obvious differences. (1) The atomic ratios of H/C, O/C, and C/N were all different for the humic acids, the soil humic acid of cake fertilizer processing had the highest contents of H and N, green manure processing of soil humic acid contained the highest content of O, while straw fertilizer processing of soil humic acid contained highest content of C. (2) Infrared analysis displayed that the three soil humic acids contained protein. Cake fertilizer processing of soil humic acid contained the most amino compounds, green manure processing of soil humic acid contained the maximum contents of hydroxyl and aliphatic hydrocarbon, while straw fertilizer processing of soil humic acid contained the highest contents of alcohol and phenol. (3) Solid 13C-NMR data indicated that cake fertilizer processing of soil humic acid contained the most carboxyl carbon, green manure processing of soil humic acid contained the highest contents of alkyl carbon and carbonyl carbon, while straw fertilizer processing of soil humic acids had the most alkoxy carbon and aromatic carbon..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1856 (2012)
An Unsupervised Classification of Hyperspectral Images Based on Pixels Reduction with Spatial Coherence Property
YUE Jiang, ZHANG Yi, XU Hang-wei, and BAI Lian-fa
In order to improve classification and edge accuracy, PRSCP and linear regression analysis are introduced; a new algorithm of unsupervised classification based on PRSCP is proposed. The algorithm procedure starts with the similarity of pixel spectral, and then makes use of minimum related window to combine similar pixeIn order to improve classification and edge accuracy, PRSCP and linear regression analysis are introduced; a new algorithm of unsupervised classification based on PRSCP is proposed. The algorithm procedure starts with the similarity of pixel spectral, and then makes use of minimum related window to combine similar pixels spatially adjacent into a block. Linear expression is applied to model the spectral vector of pixels in the same block, and significance of the linear expression is verified by F-statistic. The basic vector of block is estimated via ODLR, and blocks with similar basic vectors are combined into the same class. AVIRIS data is used to evaluate the performance of the proposed algorithm, which is also compared with K-MEANS and ISODATA. Experimental results show that the proposed algorithm outperforms K-MEANS and ISODATA in terms of classification accuracy, edge and robustness..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1860 (2012)
Influence of Composite Cathode of Ag/LiF/Al on the Performance of P3HT∶PCBM Solar Cells
ZHOU Jian-ping, CHEN Xiao-hong, and XU Zheng
The improved photocurrent of regioregular poly(3-hexylthiophene) (P3HT) and 6,6-phenyl C61-butyric acid methylester (PCBM) based polymer solar cells (PSCs) using LiF and Al cathode, modified with a reasonable thin Ag layer, was demonstrated. Using an optimal 4nm Ag layer-modified electrode gave 20% improved short-circuThe improved photocurrent of regioregular poly(3-hexylthiophene) (P3HT) and 6,6-phenyl C61-butyric acid methylester (PCBM) based polymer solar cells (PSCs) using LiF and Al cathode, modified with a reasonable thin Ag layer, was demonstrated. Using an optimal 4nm Ag layer-modified electrode gave 20% improved short-circuit photocurrent density over PSCs with only LiF/Al cathode under AM1.5G illumination of 100 mW·cm-2. The increased short-circuit photocurrent density is ascribed to plasmon enhancement of the polymer absorption by nanotextured Ag film. The fill factor and open voltage of PSCs using Ag/LiF/Al cathode are decreased compared with the control PSCs with only LiF/Al cathode, which result in the decrease in power conversion efficiency of PSCs modified with Ag film. The possible reason for the deteriorated performance of PSCs with Ag/LiF/Al is stronger carrier recombination at nanotextured Ag..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1865 (2012)
On-Orbit Response Variation Analysis of FY-3 MERSI Reflective Solar Bands Based on Dunhuang Site Calibration
SUN Ling, GUO Mao-hua, XU Na, ZHANG Li-jun, LIU Jing-jing, HU Xiu-qing, LI Yuan, RONG Zhi-guo, and ZHAO Ze-hui
MERSI is the keystone payload of FengYun-3 and there have been two sensors operating on-orbit since 2008. The on-orbit response changes obviously at reflective solar bands (RSBs) and must be effectively monitored and corrected. However MERSI can not realize the RSBs onboard absolute radiometric calibration. This paper MERSI is the keystone payload of FengYun-3 and there have been two sensors operating on-orbit since 2008. The on-orbit response changes obviously at reflective solar bands (RSBs) and must be effectively monitored and corrected. However MERSI can not realize the RSBs onboard absolute radiometric calibration. This paper presents a new vicarious calibration (VC) method for RSBs based on in-situ BRDF model, and vector radiometric transfer model 6SV with gaseous absorption correction using MOTRAN. The results of synchronous VC experiments in 4 years show that the calibration uncertainties are within 5% except for band at the center of water vapor absorption, and 3% for most bands. Aqua MODIS was taken as the radiometric reference to evaluate the accuracy of this VC method. By comparison of the simulated radiation at top of atmosphere (TOA) with MODIS measurement, it was revealed that the average relative differences are within 3% for window bands with wavelengths less than 1 μm, and 5% for bands with wavelengths larger than 1 μm (except for band 7 at 2.1 μm). Besides, the synchronous nadir observation cross analysis shows the excellent agreement between re-calibrated MERSI TOA apparent reflectance and MODIS measurements. Based on the multi-year site calibration results, it was found that the calibration coefficients could be fitted with two-order polynomials, thus the daily calibration updates could be realized and the response variation between two calibration experiments could be corrected timely; there are large response changes at bands with wavelengths less than 0.6 μm, the degradation rate of the first year at band 8 (0.41 μm) is about 14%; the on-orbit response degradation is maximum at the beginning, the degradation rates slow down after one year in operation, and after two years the responses even increase at some band with wavelengths larger than 0.6 μm..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1869 (2012)
The Application of Spectral Geological Profile in the Alteration Mapping
LI Qing-ting, LIN Qi-zhong, ZHANG Bing, and LU Lin-lin
Geological section can help validating and understanding of the alteration information which is extracted from remote sensing images. In the paper, the concept of spectral geological profile was introduced based on the principle of geological section and the method of spectral information extraction. The spectral profiGeological section can help validating and understanding of the alteration information which is extracted from remote sensing images. In the paper, the concept of spectral geological profile was introduced based on the principle of geological section and the method of spectral information extraction. The spectral profile can realize the storage and vision of spectra along the geological profile, but the spectral geological spectral profile includes more information besides the information of spectral profile. The main object of spectral geological spectral profile is to obtain the distribution of alteration types and content of minerals along the profile which can be extracted from spectra measured by field spectrometer, especially for the spatial distribution and mode of alteration association. Technical method and work flow of alteration information extraction was studied for the spectral geological profile. The spectral geological profile was set up using the ground reflectance spectra and the alteration information was extracted from the remote sensing image with the help of typical spectra geological profile. At last the meaning and effect of the spectral geological profile was discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1878 (2012)
Research on the Spectral Feature and Identification of the Surface Vegetation Stressed by Stored CO2 Underground Leakage
CHEN Yun-hao, JIANG Jin-bao, Michael D Steven, GONG A-du, and LI Yi-fan
With the global climate warming, reducing greenhouse gas emissions becomes a focused problem for the world. The carbon capture and storage (CCS) techniques could mitigate CO2 into atmosphere, but there is a risk in case that the CO2 leaks from underground. The objective of this paper is to study the chlorophyll contentWith the global climate warming, reducing greenhouse gas emissions becomes a focused problem for the world. The carbon capture and storage (CCS) techniques could mitigate CO2 into atmosphere, but there is a risk in case that the CO2 leaks from underground. The objective of this paper is to study the chlorophyll contents (SPAD value), relative water contents (RWC) and leaf spectra changing features of beetroot under CO2 leakage stress through field experiment. The result shows that the chlorophyll contents and RWC of beetroot under CO2 leakage stress become lower than the control beetroot’, and the leaf reflectance increases in the 550 nm region and decreases in the 680nm region. A new vegetation index (R550/R680) was designed for identifying beetroot under CO2 leakage stress, and the result indicates that the vegetation index R550/R680 could identify the beetroots after CO2 leakage for 7 days. The index has strong sensitivity, stability and identification for monitoring the beetroots under CO2 stress. The result of this paper has very important meaning and application values for selecting spots of CCS project, monitoring and evaluating land-surface ecology under CO2 stress and monitoring the leakage spots by using remote sensing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1882 (2012)
Effects of Spectral Resolution and Noise on the Measurement of Indices
DU Wei, LUO A-li, and ZHAO Yong-heng
In the present paper, we analysed the effects of spectral resolutions and signal-to-noise ratios (SNRs) on 19 atomic absorption line indices of Lick index system. First of all, adopting method of convolving a spectrum with a Gaussian profile, we transformed spectra into those under different resolutions and then measurIn the present paper, we analysed the effects of spectral resolutions and signal-to-noise ratios (SNRs) on 19 atomic absorption line indices of Lick index system. First of all, adopting method of convolving a spectrum with a Gaussian profile, we transformed spectra into those under different resolutions and then measured the line indices on them. Comparisons of the indices under various resolutions allow to investigate the impact of spectral resolution change on the accuracy of measurements of indices. Secondly, by adding random noises with different Gaussian distribution to a spectrum, the authors transformed theoretical spectra with no noises into those under diverse SNRs and then measured line indices on them. Comparisons of the indices under different SNRs greatly helped analyse the influence of SNR on the precision of the measurements of line indices. It comes from comparisons and analysis that the spectral resolution change can cause an index measurement change depending on the extent of the change of spectral resolution. Such a kind of change relationship varies with the indices. The lower the SNR, the less precise the measurements of indices. The effect of SNR on the measurements of indices can be ignored if SNR is larger than 25..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1886 (2012)
Feasibility of Monitoring Karst Standing Conditions with Vegetation Spectra
YUE Yue-min, WANG Ke-lin, and XIONG Ying
Karst regions are typically ecological fragile zones constrained by geological setting, which resulted in high heterogeneity of vegetation standing conditions. The karst vegetation was featured with stone, dry and high calcium carbonate content growth conditions. Based on vegetation spectral analysis and canonical corrKarst regions are typically ecological fragile zones constrained by geological setting, which resulted in high heterogeneity of vegetation standing conditions. The karst vegetation was featured with stone, dry and high calcium carbonate content growth conditions. Based on vegetation spectral analysis and canonical correspondence analysis (CCA), the present study aimed to examine the feasibility of using vegetation spectra to monitor the heterogeneous karst standing conditions. The results showed that there were significant differences between karst vegetation and non-karst vegetation within the spectral range of 1 300～2 500 nm reflectance and 400～680 nm first-derivative spectra. It was found that soil moisture and calcium carbonate contents had the most significant effects on vegetation spectral features in karst regions. Ordination diagrams of CCA could distinguish the differences of karst vegetation and non-karst vegetation. Our study demonstrates that vegetation spectra are highly related to karst standing conditions and it is feasible to monitor karst standing conditions with vegetation spectral features..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1891 (2012)
Influence of Foliar Dust on Crop Reflectance Spectrum and Nitrogen Monitoring
WANG Tao, LIU Yang, WU Hai-yun, and ZUO Yue-ming
More researches were carried out to investigate the application of spectral technology on crop nutrition diagnosis. However, the complex conditions in the field results in the uncertainty of spectrum. In this paper, the influence of foliar dust on spectral of the crop beside the nation road was studied, the differencesMore researches were carried out to investigate the application of spectral technology on crop nutrition diagnosis. However, the complex conditions in the field results in the uncertainty of spectrum. In this paper, the influence of foliar dust on spectral of the crop beside the nation road was studied, the differences of the raw spectral reflectance and first derivative spectral reflectance between the foliar with dust and the foliar washed with deionised water were analyzed, nitrogen prediction models were built on the disturbance of foliar dust. Result showed that the dust foliar spectral reflectance increased in the visible light (350～720 nm) and shortwave infrared (SWIR) (1 360～2 500 nm) regions whereas the spectral reflectance in the near infrared (NIR) (720～1 360 nm) wavelength regions decreased. There were no change rules for blue edge position, yellow edge position, red edge position, blue edge slope and yellow edge slope on the effect of foliar dust, but red edge slope, blue edge area, yellow edge area, red edge area decreased. Determinate coefficient(R2) of nitrogen prediction models reduced in the condition of foliar dust. The primary research work about the condition of foliar dust was studied which helps to provide foundation for evaluating effect of foliar dust and proposing foliar dust modification model in the future..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1895 (2012)
Division of Winter Wheat Yield Estimation by Remote Sensing Based on MODIS EVI Time Series Data and Spectral Angle Clustering
ZHU Zai-chun, CHEN Lian-qun, ZHANG Jin-shui, PAN Yao-zhong, ZHU Wen-quan, and HU Tan-gao
Crop yield estimation division is the basis of crop yield estimation; it provides an important scientific basis for estimation research and practice. In the paper, MODIS EVI time-series data during winter wheat growth period is selected as the division data; JiangSu province is study area; A division method combined ofCrop yield estimation division is the basis of crop yield estimation; it provides an important scientific basis for estimation research and practice. In the paper, MODIS EVI time-series data during winter wheat growth period is selected as the division data; JiangSu province is study area; A division method combined of advanced spectral angle mapping(SVM) and K-means clustering is presented, and tested in winter wheat yield estimation by remote sensing. The results show that: division method of spectral angle clustering can take full advantage of crop growth process that is reflected by MODIS time series data, and can fully reflect region differences of winter wheat that is brought by climate difference. Compared with the traditional division method, yield estimation result based on division result of spectral angle clustering has higher R2(0.702 6 than 0.624 8) and lower RMSE (343.34 than 381.34 kg·hm-2), reflecting the advantages of the new division method in the winter wheat yield estimation. The division method in the paper only use convenient obtaining time-series remote sensing data of low-resolution as division data, can divide winter wheat into similar and well characterized region, accuracy and stability of yield estimation model is also very good, which provides an efficient way for winter wheat estimation by remote sensing, and is conducive to winter wheat yield estimation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1899 (2012)
Effect of Different Distribution of Components Concentration on the Accuracy of Quantitative Spectral Analysis
LI Gang, ZHAO Zhe, WANG Hui-quan, LIN Ling, ZHANG Bao-ju, and WU Xiao-rong
In order to discuss the effect of different distribution of components concentration on the accuracy of quantitative spectral analysis, according to the Lambert-Beer law, ideal absorption spectra of samples with three components were established. Gaussian noise was added to the spectra. Correction and prediction modelsIn order to discuss the effect of different distribution of components concentration on the accuracy of quantitative spectral analysis, according to the Lambert-Beer law, ideal absorption spectra of samples with three components were established. Gaussian noise was added to the spectra. Correction and prediction models were built by partial least squares regression to reflect the unequal modeling and prediction results between different distributions of components. Results show that, in the case of pure linear absorption, the accuracy of model is related to the distribution of components concentration. Not only to the component we focus on, but also to the non-tested components, the larger covered and more uniform distribution is a significant point of calibration set samples to establish a universal model and provide a satisfactory accuracy. This research supplies a theoretic guidance for reasonable choice of samples with suitable concentration distribution, which enhances the quality of model and reduces the prediction error of the predict set..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1905 (2012)
Local Heating of Murine Skin by Millimeter Waves Based on HBHE
HU Shuang-xi, FAN Chun-li, YANG Li, and SUN Feng-rui
The authors deduced Gaussian function of millimeter wave power distribution, and built up a transient thermal multilayer model for the heating of murine skin by high power millimeter waves with finite volume method (FVM) based on HBHE in the present paper. We analyzed the calculated results and compared them with the rThe authors deduced Gaussian function of millimeter wave power distribution, and built up a transient thermal multilayer model for the heating of murine skin by high power millimeter waves with finite volume method (FVM) based on HBHE in the present paper. We analyzed the calculated results and compared them with the results calculated by Pennes' equation and the experimental ones; found that the temperature calculated by HBHE was more reasonable. Especially under high power millimeter wave, the calculated results were basically consistent with the experimental ones, and the superiority of the theoretical model was confirmed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1909 (2012)
Study on Polarization Spectral Feature of Suspended Sediment in the Water Body
ZHU Jin, WANG Xian-hua, and PAN Bang-long
Remote sensing of lake water based on water-leaving radiance is to retrieve the concentrations of suspended sediment, phytoplankton and yellow substance which have great impacts on spectrum to assess the water quality. Howerver, because of the complexity of the lake water compositons and the interference between the diRemote sensing of lake water based on water-leaving radiance is to retrieve the concentrations of suspended sediment, phytoplankton and yellow substance which have great impacts on spectrum to assess the water quality. Howerver, because of the complexity of the lake water compositons and the interference between the different components, it is of great difficulty to get accurate results with the reflectance spectrum method developed recently. In the present paper, the authors firstly discussed the reflectance and polarization spectral feature of suspended sediment water body, found out the relations of the reflectance and the degree of polarization of water-leaving radiance and the concentration of suspended sediment at the sensitive bands. The authors also compared the effectiveness of the retrieval approaches based on reflectance and polarization in laboratory water body and Chaohu water body respectively. The results show that in the lake water body where the constituents are very complex, the polarization information has greater capacity of anti-jamming, therefore it will have great potential applictions in lake water quality remote sensing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1913 (2012)
Study on the Soil Salinization Monitoring Based on Synthetical Hyperspectral Index
DING Jian-li, WU Man-chun, LIU Hai-xia, and LI Zheng-guang
The present paper selected the spectral reflectivity of saline soil and vegetation of Weigan-Kuqa River Delta Oasis in the northern margin of the Tarim Basin in Xinjiang as objects, and used various spectral transforms to process the data with continum removed methods, derivate spectra, reciprocal, first order differenThe present paper selected the spectral reflectivity of saline soil and vegetation of Weigan-Kuqa River Delta Oasis in the northern margin of the Tarim Basin in Xinjiang as objects, and used various spectral transforms to process the data with continum removed methods, derivate spectra, reciprocal, first order differential and root mean square etc, then analyzed the spectrum features and decided the most sensitive band ranges most relevant to salinization, and used field hyperspectral vegetation index, soil salinity index and measured synthetical spectral index to respectively establish hyperspectral quantitative models which could evaluate the soil salinization degrees. By comparing various spectral transformations of hyperspectral data the result showed that the first derivative of measured soil and vegetation hyperspectral were most sensitive to soil salinization degrees. The hyperspectral quantitative model based on measured synthetical spectral index could monitor soil salinization accurately and was better than the models simply based on vegetation index or soil salinity index. The research provided some scientific basis with soil salinization detection..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1918 (2012)
Analysis of Spectral Characteristics of Oil Film on Water Based on Wavelet Transform
LI Ying, LIU Bing-xin, LI Bao-yu, and CHEN Duo
The diagnostic features are the basis to detect and characterize the oil film on water through optical remote sensing. This work shows the results of lab spectral measurements of light diesel oil with thickness ranged 1.0～127 μm. A wavelet transform were performed to the reflectance, and the singularity (388～393 nm) waThe diagnostic features are the basis to detect and characterize the oil film on water through optical remote sensing. This work shows the results of lab spectral measurements of light diesel oil with thickness ranged 1.0～127 μm. A wavelet transform were performed to the reflectance, and the singularity (388～393 nm) was explored as the indicators of oil film thickness. The results indicate that the reflectance of light diesel oil film is higher than that of water in the range from 350～2 500 nm. There is a reflectance peak near 388 nm when the thickness of oil film is larger than 6 μm, however, no distinguished features could be recognized when oil films were thinner than 6 μm. The wavelet coefficients of the fifth decomposition level by applying Daubechies 4 (db4) mother wavelets proved successful for identifying the singularity of oil film’s reflectance spectra and its accurate position. With the thickness lager than 6 μm, the detail coefficients performed an abrupt change within the range of 388～393 nm, and became more violent while oil films’ thickness increased. This research demonstrated that oil films on water with different thickness could be distinguished based on wavelet detail coefficients, with important implications for detection of oils on water using UV and short wave optical remote sensing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1923 (2012)
Analysis on the Spectral Properties of the Stilbene 420 Laser Dye
PENG Yu-feng, MENG De-wen, PAN Xiao-li, and PENG Fang
Stilbene 420 dye solution was prepared and the laser dye absorption spectrum was measured. Q-switched frequency-doubling Nd∶YAG laser was used as the pumping source to realize the stilbene 420 dye laser and fluorescence spectra analysis. Laser spectroscopy reached the strongest peak at 425 nm and full width at half maxStilbene 420 dye solution was prepared and the laser dye absorption spectrum was measured. Q-switched frequency-doubling Nd∶YAG laser was used as the pumping source to realize the stilbene 420 dye laser and fluorescence spectra analysis. Laser spectroscopy reached the strongest peak at 425 nm and full width at half maximun (FWHM) is 1 nm. Spectral range was from 420 nm to 440 nm. Fluorescence spectrum peak was at 428.5 nm. Compared with the strongest peak laser, the wavelength difference was 3.5 nm. The highest dye conversion efficiency was 9.26%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1928 (2012)
Determination of Acidity in Oranges Based on Emphatic Orthogonal Signal Correction and Principal Component Orthogonal Signal Correction
YANG Fan, QIU Xiao-zhen, HAO Rui, GAO Fan, DU Wei, and ZHANG Zhuo-yong
Near infrared (NIR) spectroscopy technology based on a portable NIR analyzer, combined with PC-OSC algorithm, EOSC algorithm and generalized regression neural network (GRNN) has been applied to establishing quantitative models for prediction of acidity in 112 orange samples. The obtained results demonstrated that the fNear infrared (NIR) spectroscopy technology based on a portable NIR analyzer, combined with PC-OSC algorithm, EOSC algorithm and generalized regression neural network (GRNN) has been applied to establishing quantitative models for prediction of acidity in 112 orange samples. The obtained results demonstrated that the fitting and the predictive accuracy of the models with EOSC algorithm were satisfactory and the EOSC algorithm was not as susceptible to overfitting the data as PC-OSC algorithm. The correlation between actual and predicted values of calibration samples (Rc) obtained by the EOSC acidity model was 0.888 0, and prediction samples (Rp) was 0.885 6. The RMSEP was 0.081 65. The results proved that the portable NIR analyzer combined with EOSC algorithm and GRNN can be a feasible tool for the determination of acidity in oranges..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1931 (2012)
Measuring the Density of Wood and Bamboo Using Computed Tomography
PENG Guan-yun, JIANG Ze-hui, LIU Xing-e, YU Yan, YANG Shu-min, DENG Biao, XIAO Ti-qiao, and WANG Xiao-huan
CT is widespread non-destructive detection technique for wood materials, and the density measurement is a key role during this application. In the present report, the use of CT for air-dry density measurement of wood and bamboo is described. The authors found that there were marked linear correlations between air-dry dCT is widespread non-destructive detection technique for wood materials, and the density measurement is a key role during this application. In the present report, the use of CT for air-dry density measurement of wood and bamboo is described. The authors found that there were marked linear correlations between air-dry density(0.303～1.061 g·cm-3) of 24 kinds of woods and their respective CT value, as well as 25 kinds of lignin materials (including 24 kinds of woods and 1 kind of bamboo) and the CT value, both with correlation coefficient of 0.99, which belonged to the CT technological breakthrough for wood quantitative detection. These research results show that CT is an appropriate way to measure density for wood and bamboo, and would provide technical support for CT used in the field of wood science research and wood processing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1935 (2012)
Detection of Trace Uranium in Air with Field Spectrometry
YANG Ya-xin, XIAO Sai-jin, LIU Qing-cheng, HUANG Long-zhu, PENG Dao-feng, and ZHENG Yong-ming
As a natural radioactive element, uranium and its compounds exist as aerosol and transfer in air. In gas phase, uranium can cause various kinds of radioactive damage to human body. The change in its concentration in a local area is related to the exploration and utilization of nuclear energy. Therefore, the developmentAs a natural radioactive element, uranium and its compounds exist as aerosol and transfer in air. In gas phase, uranium can cause various kinds of radioactive damage to human body. The change in its concentration in a local area is related to the exploration and utilization of nuclear energy. Therefore, the development of field method for rapid uranium detection in air sample is very important. In this contribution, the air samples over uranium ores collected by a general pump was absorbed with 2.0 mol·L-1 nitrate and then reacted with solid reagent kit. When the reaction between trace uranium and chromogenic reagent was finished, the homemade portable photometer was used to measure the absorbance. The results showed that the concentration of uranium in air samples over low grade uranium ores can be successfully determined by the present method and the values agree with that obtained by ICP-MS. The RSD measured by the new method was 1.72%. The application of the new field spectrometry in discriminating uranium ores from other ores has the potential advantages of easy operation, cost-saving and high accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1939 (2012)
Investigation of Spectroscopy of ZnCuInS/ZnS Quantum Dots and Poly-TPD
ZHANG Yu, LIU Wen-yan, ZHANG Tie-qiang, WANG Ya-nan, GU Peng-fei, WANG Peng, WANG Yi-ding, and WANG Fang-rong
In the present paper ZnCuInS/ZnS core/shell quantum dots were prepared with the particle size of 3.2 nm. Its radiation is based on the donor-acceptor pair transitions, not the band edge emission. According to the measurement of photoluminescence spectrum emitted by ZnCuInS/ZnS core/shell quantum dots, the emitting peakIn the present paper ZnCuInS/ZnS core/shell quantum dots were prepared with the particle size of 3.2 nm. Its radiation is based on the donor-acceptor pair transitions, not the band edge emission. According to the measurement of photoluminescence spectrum emitted by ZnCuInS/ZnS core/shell quantum dots, the emitting peak of 620 nm and the full width at half-maximum of 95 nm were achieved as red emitter; meanwhile, organic poly(N,N′-bis(4-butylphenyl)-N,N′-bis(phenyl)benzidine) (Poly-TPD) film was deposited and used as cyan-emitter with the peak of 480 nm. Two structures of Poly-TPD were analyzed and discussed according to the photoluminescence spectrum. Two wavelengths are complementary color. Therefore, two films were deposited one by one as bilayer emitter to obtain the complementary emission. After the suitable bias was applied on the films, the white emission was achieved with the Commission Internationale de l’Eclairage (CIE) chromaticity coordinates of (0.336, 0.339) and color rendering index of 92. Therefore, the bilayer-structure is a promising candidate for white light emitting diodes fabrication..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1943 (2012)
Synthesis of Maleic Anhydride-Acrylamide Copolymer and Study of Its Adsorption Properties by ICP-AES
CAI Qing, XIE Zhi-hai, JIANG Xiao-yan, LIU Yu, and YAN Hong-tao
A novel adsorbent was prepared with maleic anhydride and acrylamide as functional monomer, N,N-methylenebisacrylamide as cross-linking agent, and ammonium persulfate as initiator through aqueous polymerization reaction. The adsorbent was characterized by Fourier transmission infrared spectra (FTIR) and ThermogravimetryA novel adsorbent was prepared with maleic anhydride and acrylamide as functional monomer, N,N-methylenebisacrylamide as cross-linking agent, and ammonium persulfate as initiator through aqueous polymerization reaction. The adsorbent was characterized by Fourier transmission infrared spectra (FTIR) and Thermogravimetry (TG). The adsorption properties and selectivity properties were investigated by inductively coupled plasma atomic emission spectrum (ICP-AES). The result indicated that the optimum acidity was pH 3.5 and the reaction attained equilibrium at 1 h under stirring. The polymer adsorbent exhibited high selectivity for Fe3+ and its saturated adsorption capacity was 78.81 mg·g-1. The adsorption kinetics was well described by pseudo-second kinetic equation, and the adsorption of the copolymer for Fe3+ accorded with Freundlich isothermal model. The adsorption process was found to be endothermic..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1946 (2012)
Determination and Distribution Patterns Analysis of Rare Earth Elements in Sediments of Prydz Bay
WANG Zhi-guang, CHEN Fa-rong, ZHENG Li, BAO Hui-xin, LI Jing-xi, YU Xi-juan, and WANG Xiao-ru
A sensitive quantificational method was developed for the analysis of Sc, Y, La, Ce, Pr, Nd, Sm, Eu, etc. in sediments of Prydz Bay by inductively coupled plasma mass spectrometry, and then the REE distribution patterns were analyzed. The samples were digested by microwave using HNO3-H2O2-HF as oxidant. The results shoA sensitive quantificational method was developed for the analysis of Sc, Y, La, Ce, Pr, Nd, Sm, Eu, etc. in sediments of Prydz Bay by inductively coupled plasma mass spectrometry, and then the REE distribution patterns were analyzed. The samples were digested by microwave using HNO3-H2O2-HF as oxidant. The results showed that the total contents of rare earth elements in eight sites ranged from 117.35 to 348.63 μg·g-1 and the maximum value was 2.97 times of the minimum value. The REE distribution patterns of different sites in sediments were basically identical and there was an obvious fractionation between LREEs and HREEs. The linear correlation of the method was preferable (r=0.999 7～1.000 0). The RSDs (n=3) were no more than 5.0%, and the relative errors were no more than 10%. The detection limits of rare earth elements reached ng·L-1 level except for Sc. This method was suitable for the analysis of REEs in sediments with the advantages of rapidness, simplicity, high precision and accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1950 (2012)
Characteristics of Chemical Composition of Glass Finds from the Qiemo Tomb Sites on the Silk Road
CHENG Qian, GUO Jin-long, WANG Bo, and CUI Jian-feng
Qiemo was an ancient country on the south branch of the Silk Road. The Zagunluke tomb site is located at the Qiemo County of the Xinjiang Uygur Autonomous Region. Glass beads and only colourless glass cup were excavated from the 3rd cultural layer of the tomb site M133 and M49, dated between the 1st AD-6th AD. LA-ICP-AQiemo was an ancient country on the south branch of the Silk Road. The Zagunluke tomb site is located at the Qiemo County of the Xinjiang Uygur Autonomous Region. Glass beads and only colourless glass cup were excavated from the 3rd cultural layer of the tomb site M133 and M49, dated between the 1st AD-6th AD. LA-ICP-AES was applied to analyse chemical composition of these glass finds with the corning glass as reference. According to the result, characteristics of chemical composition are very similar to typical soda-lime glass, which indicates the glasses were imported productions from the west. These soda-lime glasses were divided into two groups in terms of flux source: natron glass and plant ash glass. This analytical research indicates the history of glass trade and communication between the East and the West on the Silk Road..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1955 (2012)
Determination of Six Metal Elements in Animal Samples by Flame Atomic Absorption Spectrometry with Wet Digestion
LIU Ming-jia, ZHOU Zhi-qiang, ZU Yuan-gang, and ZHANG Yu-hong
The contents of 6 metal elements (Ca, Mg, K, Na, Cu and Fe ) were determined in serum, urine, feces and different tissue and organs (heart, kidney, stomach, liver, spleen, intestine and lung) of Wistar rats and mice by flame atomic absorption spectrometry (FAAS) with wet digestion. The samples were digested by the mixtThe contents of 6 metal elements (Ca, Mg, K, Na, Cu and Fe ) were determined in serum, urine, feces and different tissue and organs (heart, kidney, stomach, liver, spleen, intestine and lung) of Wistar rats and mice by flame atomic absorption spectrometry (FAAS) with wet digestion. The samples were digested by the mixture of HNO3 and HClO4 (4∶1, V/V) at 120 ℃, the correlation coefficient for the standard curves was 0.999 4～0.999 8, the relative standard deviation (RSD) was from 0.33% to 4.52%, and the recovery for the samples was from 97.7% to 104.2%, meeting the demand of elements content determination in biological samples. The assay method for the determination of the 6 metal elements in animal samples established in this study has the advantages of easy operation, high sensitivity, less sample requiring and accurate results, and the method can be widely used in the determination of various metal elements in biological samples..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1961 (2012)
Temperature Effect Correction for Chang’E-3 Alpha Particle X-Ray Spectrometer
WU Ming-ye, WANG Huan-yu, PENG Wen-xi, ZHANG Cheng-mo, ZHANG Jia-yu, CUI Xing-zhu, LIANG Xiao-hua, WANG Jin-zhou, YANG Jia-wei, FAN Rui-rui, LIU Ya-qing, DONG Yi-fan, WU Feng, and ZHAO Xiao-yun
Alpha particle X-ray spectrometer (APXS) is one of the payloads of Chang’E-3 lunar rover of China’s Lunar Exploration Project. The present paper introduces briefly the components of APXS, how it works and its working environment on the lunar surface. The environmental temperature effect has been studied with simulationAlpha particle X-ray spectrometer (APXS) is one of the payloads of Chang’E-3 lunar rover of China’s Lunar Exploration Project. The present paper introduces briefly the components of APXS, how it works and its working environment on the lunar surface. The environmental temperature effect has been studied with simulations and experiments, and the results show that the temperature of the APXS sensor will be varying during the measuring on the lunar surface. And another experiment reveals that the energy resolution becomes worse if the sensor’s temperature is varying. In this paper, a correction method based on Pearson’s chi-squared test is presented. The method can improve the energy resolution when the sensor’s temperature is varying. We have tested the method with the spectra acquired by APXS in the temperature varying period of Temperature Cycling Test, and the results show that the method is efficient and reliable..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1965 (2012)
The Element Determination of Six Samples of Petal Powders by Using XRF Spectrometry
MEI Yan, MA Mi-xia, and NIE Zuo-ren
Elements and contents in three kinds of petal powders of white and red rose, carnation, and butterfly orchis were determined by using XRF technic, and the data for every group were compared and analysed. The results indicated that all powders contain no toxic elements determined but have lots of normal elements and traElements and contents in three kinds of petal powders of white and red rose, carnation, and butterfly orchis were determined by using XRF technic, and the data for every group were compared and analysed. The results indicated that all powders contain no toxic elements determined but have lots of normal elements and trace elements, such as Fe, Cu, Zn, Mn, Ni, Si, Sr, and Rb. The same sort of powder had approximately equivalent elements but their contents are different, and the element content of the white sort. was higher than the red one..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1969 (2012)
Study of Dioscorea Opposita Thunb from Different Producing Areas with XRF and PXRD
ZHANG Jing-chao, ZHU Yan-ying, DING Xi-feng, LIU Mei-yi, GUO Xi-hua, WU Peng-le, and GUAN Ying
The contents of various elements in rhizoma dioscoreae were analyzed and compared with those of shishou D. opposita Thunb on the whole jointly by XRF and PXRD. The results showed that the element Cu, Al and Mn could not be detected in rhizoma dioscoreae, but the element Mg, Zn and Cr were found, and other elements contThe contents of various elements in rhizoma dioscoreae were analyzed and compared with those of shishou D. opposita Thunb on the whole jointly by XRF and PXRD. The results showed that the element Cu, Al and Mn could not be detected in rhizoma dioscoreae, but the element Mg, Zn and Cr were found, and other elements contents changed to different degrees; there are starch and whewellite in both groups, the crystal type of starches separated from rhizoma dioscoreae cultivars was a typical B-type pattern, but as C-type and V-type in shishou D. opposita Thunb, which is a mixture of A-type, B-type and V-type. The combination of two testing techniques could be applied to the mensuration and analysis of the elements and micro-structural of Dioscorea opposita Thunb which could be from different producing areas..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1972 (2012)
XANES Study of Lead Speciation in Duckweed
CHU Bin-bin, LUO Li-qiang, XU Tao, YUAN Jing, SUN Jian-ling, ZENG Yuan, MA Yan-hong, and YI Shan
Qixiashan lead-zinc mine of Nanjing was one of the largest lead zinc deposits in East China. Its exploitation has been over 50 years, and the environmental pollution has also been increasing. The lead concentration in the local environment was high, but lead migration and toxic mechanism has not been clear. Therefore, Qixiashan lead-zinc mine of Nanjing was one of the largest lead zinc deposits in East China. Its exploitation has been over 50 years, and the environmental pollution has also been increasing. The lead concentration in the local environment was high, but lead migration and toxic mechanism has not been clear. Therefore, biogeochemistry research of the lead zinc mine was carried out. Using ICP-MS and Pb-LⅢ edge XANES, lead concentration and speciation were analyzed respectively, and duckweed which can tolerate and enriched heavy metals was found in the pollution area. The results showed that the lead concentration of duckweed was 39.4 mg·kg-1. XANES analysis and linear combination fit indicated that lead stearate and lead sulfide accounted for 65% and 36.9% respectively in the lead speciation of duckweed, suggesting that the main lead speciation of duckweed was sulfur-containing lead-organic acid..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1975 (2012)
Macromolecular Aromatic Network Characteristics of Chinese Power Coal Analyzed by Synchronous Fluorescence and X-Ray Diffraction
YE Cui-ping, FENG Jie, and LI Wen-ying
Coal structure, especially the macromolecular aromatic skeleton structure, has a strong influence on coke reactivity and coal gasification, so it is the key to grasp the macromolecular aromatic skeleton coal structure for getting the reasonable high efficiency utilization of coal. However, it is difficult to acquire thCoal structure, especially the macromolecular aromatic skeleton structure, has a strong influence on coke reactivity and coal gasification, so it is the key to grasp the macromolecular aromatic skeleton coal structure for getting the reasonable high efficiency utilization of coal. However, it is difficult to acquire their information due to the complex compositions and structure of coal. It has been found that the macromolecular aromatic network coal structure would be most isolated if small molecular of coal was first extracted. Then the macromolecular aromatic skeleton coal structure would be clearly analyzed by instruments, such as X-ray diffraction (XRD), fluorescence spectroscopy with synchronous mode (Syn-F), Gel permeation chromatography (GPC) etc. Based on the previous results, according to the stepwise fractional liquid extraction, two Chinese typical power coals, PS and HDG, were extracted by silica gel as stationary phase and acetonitrile, tetrahydrofuran (THF), pyridine and 1-methyl-2-pyrollidinone (NMP) as a solvent group for sequential elution. GPC, Syn-F and XRD were applied to investigate molecular mass distribution, condensed aromatic structure and crystal characteristics. The results showed that the size of aromatic layers (La) is small(3～3.95 nm) and the stacking heights (Lc) are 0.8～1.2 nm. The molecular mass distribution of the macromolecular aromatic network structure is between 400 and 1 130 amu, with condensed aromatic numbers of 3～7 in the structure units..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1979 (2012)
The Microstructure and Phase Composition of Metal Melting Marks Caused by Different Fire
WANG Hai-rong, LIU Jian-yong, YAO Hao-wei, and LIANG Dong
Four different types of molten metal fire marks were studied through X-ray diffraction (XRD) and 3D image processing software (Image-pro). As a result, the microstructure, average grain size, phase composition and its distribution was obtained. The results showed that on the surface of molten metal fire marks there maiFour different types of molten metal fire marks were studied through X-ray diffraction (XRD) and 3D image processing software (Image-pro). As a result, the microstructure, average grain size, phase composition and its distribution was obtained. The results showed that on the surface of molten metal fire marks there mainly existed cubic crystal of Cu2O, cellular crystals of Cu and columnar crystals of Cu. And in four different modes of fire, the microstructure and composition of molten metal marks was of significant difference, that is: (1) the average grain size of molten marks by a short circuit fire was about 3～5 μm, and its Cu2O was the lowest; melt marks by circuit overload had an average grain size similar to short-circuit, but their Cu2O content was about 30%; (2) melt marks by secondary short-circuit contained a certain number of larger diameter micro-hole, and their average grain size was about 30 μm; broadening and splitting provision of the diffraction peaks of Cu and Cu2O showed that their ablation was the deepest; (3) melting marks by fire showed the equiaxed maximum intensity of Cu2O diffraction peaks, and there was almost no micro-holes..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1984 (2012)
Research on the Composition Characteristics of Chinese Ancient Southern White Porcelain
WU Juan, YE Zheng-long, WU Jun-ming, ZHANG Mao-lin, LI Qi-jiang, WANG Li-li, and JIANG Peng-fei
The southern white porcelain is the rise in our country’s pottery, it is later than the development of northern white porcelain, but it is rising stars, blockbuster, well-grounded, keeping continuous. Jingdezhen kiln and Dehua kiln are the most representative kilns among the southern white porcelain kilns. the present The southern white porcelain is the rise in our country’s pottery, it is later than the development of northern white porcelain, but it is rising stars, blockbuster, well-grounded, keeping continuous. Jingdezhen kiln and Dehua kiln are the most representative kilns among the southern white porcelain kilns. the present paper used EDXRF to test 30 pieces of Song, Yuan and Ming period’ Dehua white porcelains and Jingdezhen Yuan dynasty Shufu white porcelains samples to analyze the different characteristics of the bodies and the glaze of these samples in terms of time and space. The results show that in the bodies and the glaze of Jingdezhen Shufu white porcelains the iron content is obviously on the high side, and the Dehua white porcelains’ potassium content is obviously on the high side, and along with time development they have been in a rising trend, which should be the main reason for the sudden rise of Dehua white porcelain sculptures..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1989 (2012)
Spectral Calibration for the Large Aperture Infrared Radiometer
YE Zhao, WAN Zhi, LI Xian-sheng, REN Jian-wei, and LIU Hong-xing
The present paper introduced a spectral calibration method to calibrate a large aperture infrared radiation facility. We developed a radiometer which consisted of optical system, infrared detectors(cavity pyroelectric detector and HgCdTe detector 2～14 μm), fine mechanical modulator, lock in amplifier, signal processor,The present paper introduced a spectral calibration method to calibrate a large aperture infrared radiation facility. We developed a radiometer which consisted of optical system, infrared detectors(cavity pyroelectric detector and HgCdTe detector 2～14 μm), fine mechanical modulator, lock in amplifier, signal processor, etc. At first, we analyzed the method on how to measure the spectral calibration of the large aperture infrared radiometer, and established the spectral calibration facility. Then, we tested the nonlinear response for the cavity pyroelectric detector and HgCdTe detector. Finally, we used the cavity pyroelectric detector to calibrate the relative spectral responsivity of HgCdTe detector at several wavelengths on the facility. Through the comparison of the two methods for measuring the relative spectral responsivity, the average of multiple measurements and comparative analysis of two methods were given. The uncertainty analysis of the whole system showed that the measurement uncertainty of the facility was better than 3.4%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1994 (2012)
Analysis of Multi-Micromirrors Tilt Error in Space-Modulated Fourier Transform Infrared Spectrometry
ZHENG Ying, LIANG Jing-qiu, and LIANG Zhong-zhu
The system of space-modulated Fourier transform infrared spectrometer without moving parts is stable and compact, moreover, it can realize the on-line monitoring and real-time detection. The position accuracy of multi-micromirrors as the key components has a great influence on spectrometric performance. In the present The system of space-modulated Fourier transform infrared spectrometer without moving parts is stable and compact, moreover, it can realize the on-line monitoring and real-time detection. The position accuracy of multi-micromirrors as the key components has a great influence on spectrometric performance. In the present paper, the multi-mcromirrors tilt error caused by optical path difference changes was calculated and simulated. The analysis shows that, as the multi-micromirrors tilt angle increased, the interference pattern contrast decreased and the signal to noise ratio reduced. The results could be used in the tolerance distribution and the systemic alignment in the next step..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1999 (2012)
Research on the Phase-Shifted Fiber Grating Spectrum Characteristics in the Inhomogeneous Strain Fields
WANG Zheng-fang, WANG Jing, SUI Qing-mei, JIANG Shan-chao, JIA Lei, and CAO Yu-qiang
Based on the transfer matrix method, the spectrum characteristics of phase-shifted fiber grating were analyzed systematically, and the reflection spectra of phase-shifted fiber grating under uniform strain, linear strain, secondary strain and cubic strain were simulated respectively. The regularity conclusion that the Based on the transfer matrix method, the spectrum characteristics of phase-shifted fiber grating were analyzed systematically, and the reflection spectra of phase-shifted fiber grating under uniform strain, linear strain, secondary strain and cubic strain were simulated respectively. The regularity conclusion that the influence of different strain distribution functions on reflectivity, transmission bandwidth, wavelength of transmission window and spectral shape came out. In order to verify the simulation result, strain-tuning equipment was designed based on cantilever with different structures. Finite element method was carried out to simulate the strain distribution of phased shift fiber grating fixed on the surface of cantilever during the strain-tuning experiment. Experiment result demonstrated that the reflection spectra of phase-shifted fiber grating under uniform strain, linear strain and secondary strain exhibited a regular change, which is in agreement with simulation results..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 2003 (2012)
The Design and Experiment of Multi-Parameter Water Quality Monitoring Microsystem Based on MOEMS Microspectrometer
WEI Kang-lin, WEN Zhi-yu, GUO Jian, and CHEN Song-bo
Aiming at the monitoring and protecting of water resource environment, a multi-parameter water quality monitoring microsystem based on microspectrometer was put forward in the present paper. The microsystem is mainly composed of MOEMS microspectrometer, flow paths system and embedded measuring & controlling system.Aiming at the monitoring and protecting of water resource environment, a multi-parameter water quality monitoring microsystem based on microspectrometer was put forward in the present paper. The microsystem is mainly composed of MOEMS microspectrometer, flow paths system and embedded measuring & controlling system. It has the functions of self-injecting samples and detection regents, automatic constant temperature, self -stirring, self- cleaning and samples’ spectrum detection. The principle prototype machine of the microsystem was developed, and its structure principle was introduced in the paper. Through experiment research, it was proved that the principle prototype machine can rapidly detect quite a few water quality parameters and can meet the demands of on-line water quality monitoring, moreover, the principle prototype machine has strong function expansibility..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 2009 (2012)
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 32, Issue 7, 1 (2012)
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