Journals >Spectroscopy and Spectral Analysis
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2015
Volume: 35 Issue 4
59 Article(s)
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Research Article
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1 (2015)
Near-Infrared Imaging Using a High-Speed Monitoring Near Infrared Hyperspectral Camera (Compovision)
Daitaro Ishikawa, Asako Motomura, Yoko Igarashi, and Yukihiro Ozaki
This review paper reports near-infrared (NIR) imaging studies using a newly-developed NIR camera,Compovision.Compovision can measure a significantly wide area of 150 mm×250 mm at high speed of between 2 and 5 s.It enables a wide spectral region measurement in the 1 000～2 350 nm range at 6 nm intervals.We investigaThis review paper reports near-infrared (NIR) imaging studies using a newly-developed NIR camera,Compovision.Compovision can measure a significantly wide area of 150 mm×250 mm at high speed of between 2 and 5 s.It enables a wide spectral region measurement in the 1 000～2 350 nm range at 6 nm intervals.We investigated the potential of Compovision in the applications to industrial problems such as the evaluation of pharmaceutical tablets and polymers.Our studies have demonstrated that NIR imaging based on Compovision can solve several issues such as long acquisition times and relatively low sensitivity of detection.NIR imaging with Compovision is strongly expected to be applied not only to pharmaceutical tablet monitoring and polymer characterization but also to various applications such as those to food products,biomedical substances and organic and inorganic materials..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 865 (2015)
Study on Characteristics of Terahertz Spectra of Organic Functional Groups
MA Chun-qian, XU Xiang-dong, ZOU Rui-jiao, LIU Yi-ke, HE Qiong, JIANG Ya-dong, HUANG Rui, WEN Yue-jiang, and SUN Zi-qiang
Fourier transform infrared (FTIR) was exploited to measure terahertz (THz) spectra in the wave number range of 30~300 cm-1 for saturated straight chain organic molecules at room temperature.The results reveal that different organic functional groups exhibit different THz spectral characteristics.The absorption peaks ofFourier transform infrared (FTIR) was exploited to measure terahertz (THz) spectra in the wave number range of 30~300 cm-1 for saturated straight chain organic molecules at room temperature.The results reveal that different organic functional groups exhibit different THz spectral characteristics.The absorption peaks of vibration modes of organic crystal lattice locate in high frequency range of THz,while those of vibration modes of intermolecular hydrogen (H) bonds appear in low frequency range of THz.Moreover,a typical absorption peak of intermolecular H bonds caused by saturated straight-chain monohydric alcohol hydroxyl functional groups locates at 57 cm-1,while a characteristic absorption peak of intermolecular hydrogen bonds caused by triacontanoic acid carboxyl functional groups appears at 74 cm-1.The intermolecular H bonds not only result in that the THz absorbing abilities of triacontanol and triacontanoic acid are significantly stronger than that of triacontane,but also cause regular red-shift and blue-shift of the THz absorption peaks of triacontanoic acid,as compared with those of triacontanol.In addition,density functional theory (DFT) B3LYP/6-311G(d,p) basis set was employed to simulate the THz spectra of saturated straight-chain alkane,alkanol and acid,respectively.The simulation results indicate that for the organic molecules with stronger intermolecular H bonds,lower consistent degree of the THz spectrum simulated from monomer molecule with the THz spectrum experimentally measured will occur.Moreover,the simulation results of dimer structures agree well with the measured spectra as compared to those simulated from monomer molecule structures.The results presented in this work are of great significance not only to the study of the THz spectral characteristics of other organic functional groups,but also to the clarification of the vibration modes of organic molecules.Particularly,our results are also helpful for clarifying the THz response theory of organics,and for exploiting the applications of organic materials in THz devices..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 870 (2015)
Construction and Characterization of B850-Only LH2 Energy Transfer System in Purple Bacteria
LI Kai, ZHAO Chun-gui, YUE Hui-ying, YANG Su-ping, QU Yin-bo, and JIAO Nian-zhi
To seek microscopic molecular mechanism of energy transfer and complex reconstitution in the photosynthesis,the conditions for construction of B850-only peripheral light-harvesting complex (LH2) and their properties were investigated using absorption,fluorescence spectroscopy,molecular sieve chromatography,ultrafiltratTo seek microscopic molecular mechanism of energy transfer and complex reconstitution in the photosynthesis,the conditions for construction of B850-only peripheral light-harvesting complex (LH2) and their properties were investigated using absorption,fluorescence spectroscopy,molecular sieve chromatography,ultrafiltration and sodium dodecylsulfate polyacrylamide gel electrophoresis (SDS-PAGE) from the purple bacteria.The results indicated that bacteriochlorophylls (BChl) of B800 incubated in 10 mmo·L-1 Tris-HCl (pH 8.0) buffer are selectively released from their binding sites of LH2 of Rhodobacter azotoformans (A-LH2) by 0.08% (W/V) SDS.B850-only A-LH2 was constructed after removing free BChl mixing with 10% methyl alcohol by ultrafiltration.B850 BChl was released after A-LH2 was incubated for 240 min in dark at room temperature (RT).While BChl of B800 incubated in pH 1.9 buffer were selectively released from their binding sites of LH2 of Rhodopseudomonas palustris (P-LH2).The authors acquired two components using molecular sieve chromatography.Free BChl of one component was not removed and self-assembled to P-LH2.The other removed free BChl and B850-only P-LH2 was constructed.B850 unchanged after P-LH2 was incubated.P-LH2 α and β subunits have different molecular weights,but those of A-LH2 are in the contrary.It is concluded that B850-only P-LH2 is more stable than A-LH2.The enigmatic split of the B800 absorption band was not observed in these LH2,but we acquired two kinds of B800-released LH2 from Rhodopseudomonas palustris.The authors’ results may provide a new light to separate homogeneous Apoprotein LH2..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 875 (2015)
A Detection Technique for Gas Concentration Based on the Spectral Line Shape Function
ZHOU Mo, YANG Bing-chu, and TAO Shao-hua
The methods that can rapidly and precisely measure concentrations of various gases have extensive applications in the fields such as air quality analysis,environmental pollution detection,and so on.The gas detection method based on the tunable laser absorption spectroscopy is considered a promising technique.For the inThe methods that can rapidly and precisely measure concentrations of various gases have extensive applications in the fields such as air quality analysis,environmental pollution detection,and so on.The gas detection method based on the tunable laser absorption spectroscopy is considered a promising technique.For the infrared spectrum detection techniques,the line shape function of an absorption spectrum of a gas is an important parameter in qualitative and quantitative analysis of a gas.Specifically,how to obtain the line shape function of an absorption spectrum of a gas quickly and accurately is a key problem in the gas detection fields.In this paper we analyzed several existing line shape functions and proposed a method to calculate precisely the line shape function of a gas,and investigated the relation between the gas concentration and the peak value of a line shape function.Then we experimentally measured the absorption spectra of an acetylene gas in the wavelength range of 1 515～1 545 nm with a tunable laser source and a built-in spectrometer.With Lambert-Beer law we calculated the peak values of the line shape function of the gas at the given frequencies,and obtained a fitting curve for the line shape function in the whole waveband by using a computer program.Comparing the measured results with the calculated results of the Voigt function,we found that there was a deviation between the experimental results and the calculated results.And we found that the measured concentration of the acetylene gas by using the fitting curve of the line shape function was more accurate and compatible with the actual situation.Hence,the empirical formula for the line shape function obtained from the experimental results would be more suitable for the concentration measurement of a gas.As the fitting curve for the line shape function of the acetylene gas has been deduced from the experiment,the corresponding peak values of the spectral lines can be immediately calculated out from the curve and used for the measurements of different concentrations of acetylene gases.Therefore,the calculation for the line shape function values is greatly simplified.The obtained data of the line shape function of the acetylene gas can be used for remote sensing of the gas,and the proposed method can also be applied for the measurements of line shape functions of other gases..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 881 (2015)
Purification of PTCDA by Vacuum Sublimation and Spectral Test and Analysis
ZHANG Xu, ZHANG Jie, YAN Zhao-wen, ZHOU Xing-yu, and ZHANG Fu-jia
The organic semiconductor 3,4,9,10 perylenetetracarboxylic dianhydride (PTCDA) with the purity of 97.5% was purified by sublimation to 99.9%.The high-purity PTCDA material was measured by mass spectra,infrared spectrum and X-ray photoelectron spectroscopy (XPS).Detailed analysis revealed its molecular structure,the forThe organic semiconductor 3,4,9,10 perylenetetracarboxylic dianhydride (PTCDA) with the purity of 97.5% was purified by sublimation to 99.9%.The high-purity PTCDA material was measured by mass spectra,infrared spectrum and X-ray photoelectron spectroscopy (XPS).Detailed analysis revealed its molecular structure,the forming of chemical bond,the vibration modes of atoms in equilibrium lattice position,electronic configuration and the shift of binding energy of atoms.Based on the infrared spectrum analysis,the molecular structure of PTCDA is consisting of perylene core group with five C rings and two anhydrides located at both ends of perylene core,which is mainly bonded with covalent bond.The stretching vibration of C atoms in the crystal lattice dominates in their equilibrium positions.The PTCDA molecules have a large number of π electrons which can move freely;the intermolecular delocalized π bond overlap determines the conductivity of PTCDA.Based on XPS analysis,it can be found that there exist two kinds of C atoms with different binding energy:285.3 and 288.7 eV,respectively,corresponding to the C atoms in the perylene ring and anhydride.In addition,there are two kinds of O atoms,i.e.COand C—O—C,whose bonding energy is 531.3 and 533.1 eV,respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 885 (2015)
Synthesis and Luminescence Properties of BiOCl:Dy3+ Phosphors for NUV Excited White Light-Emitting Diodes
KUANG Qing-liang, LI Yong-jin, QIU Jian-bei, YIN Zhao-yi, YANG Zheng-wen, SONG Zhi-guo, WAN Rong-hua, LIU Qun, and ZHOU Yu-ting
In the present paper,we reported the luminescence properties of BiOCl:Dy3+ and BiOCl:Dy3+,Li+ phosphor synthesized by conventional solid state method.X-ray diffraction (XRD) and excitation and emission spectroscopy were used to characterize the samples.Results show that pure tetragonal BiOCl:Dy3+ crystals can be syntheIn the present paper,we reported the luminescence properties of BiOCl:Dy3+ and BiOCl:Dy3+,Li+ phosphor synthesized by conventional solid state method.X-ray diffraction (XRD) and excitation and emission spectroscopy were used to characterize the samples.Results show that pure tetragonal BiOCl:Dy3+ crystals can be synthesized successfully at 500 ℃,and Li+ ion dopant improves the crystallinity of samples furtherly.Under near UV light excitation,the samples give the characteristic luminescence of Dy3+ ions located at 478 (blue) and 574 nm (yellow),which show a low yellow-to-blue intensity ratio (Y/B) of Dy3+ emission and white light emission.Moreover,codoping of Li+ ion can realize the enhancement of emission intensity and the adjustment of emission color.The characteristics of BiOCl:Dy3+ phosphor,low temperature preparation,good near ultraviolet excitation and white light emission make it to a promising near-ultraviolet WLED phosphor..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 889 (2015)
How to Remove Water Absorption Bands Completely from IR Spectra of Aqueous Solution
BAI Sha-sha, WANG Huan, CHEN Yu-jing, and WANG Hai-shui
Infrared spectral studies of aqueous solution have been severely limited by the strong water absorption.Usually,it is very difficult to experimentally achieve perfect compensation between the amount of water that contributes to the sample and background spectra.In the present paper,we introduced a new method to make thInfrared spectral studies of aqueous solution have been severely limited by the strong water absorption.Usually,it is very difficult to experimentally achieve perfect compensation between the amount of water that contributes to the sample and background spectra.In the present paper,we introduced a new method to make the infrared bands of water disappear during the measurement of an infrared spectrum for aqueous solution.Both background spectrum of the empty ATR cell and that of the water on ATR cell are used in sequence.Qualified infrared spectra of 10% K2CO3 and 10% BSA aqueous solutions were successfully obtained by ATR accessory (single-reflection) without water interference.The experimental results demonstrated that the new method is fast,effective and powerful.The limitation of the new method is also discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 894 (2015)
Spectrum Research on Rheology of High Rank Coal
YU Li-ye, JU Yi-wen, and LI Xiao-shi
Aiming to discuss the change characteristic of macromolecular structures of high rank coal in different rheological conditions,the high rank undeformed coal from southern Qinshui basin and the coal after variable temperature and variable pressure rheology experiments were investigated and analyzed in detail through FouAiming to discuss the change characteristic of macromolecular structures of high rank coal in different rheological conditions,the high rank undeformed coal from southern Qinshui basin and the coal after variable temperature and variable pressure rheology experiments were investigated and analyzed in detail through Fourier transform infrared spectroscopy (FTIR) and laser Raman spectra analysis.The result shows that the texture and composition of different types of rheological coals under different temperature and pressure exhibit significant differences.Experiments of variable temperature and pressure of high rank coal (temperature:300~400 ℃,confining pressure:50~100 MPa,strain:less than 10% and strain rate:10-4~10-7·s-1) will distort their macromolecular structures and recombine the chemistry structures.When the temperature is 300 ℃ or 350 ℃,the high rank coal generates brittle or brittle-ductile rheology easily,mechanical energy transforms to heat energy,some branches and functional groups with weaker bond energy break and fall off,which split as dissociative micromolecule,with stress degradation as principal role,and stress polycondensation occurs with aromatic texture increasing.When the temperature is up to 400 ℃,ductile rheology of the high rank coal occurs with the secondary defects increasing,mechanical energy transforms to strain energy which helps the early shedding small molecules be embedded or adsorbed in the defect or on the surface of macromolecular preferentially and change the aliphatic and aromatic structures.It is affected by stress degradation and polycondensation progress,and the latter is dominated.The confining pressure and water injection of coal do not have much effect on the macromolecular structure obviously..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 899 (2015)
The Significance of Analysis of Soil from the Surface of Hetao Plain,Inner Mongolia with Near Infrared Spectra
XIA Yuan-yuan, CAO Jian-jin, WU Zheng-quan, YUAN Xue-ling, and LIN Zu-xu
The technology of near infrared spectrum,marked by its convenience and effectiveness,which has been applied extensively in lithological analysis,is suitable for component analysis of regional geology,due to its superiority in analyzing numerous samples in a relatively short time.Since different mineral molecule peaks wThe technology of near infrared spectrum,marked by its convenience and effectiveness,which has been applied extensively in lithological analysis,is suitable for component analysis of regional geology,due to its superiority in analyzing numerous samples in a relatively short time.Since different mineral molecule peaks will show different characters when being analyzed in the near infrared spectrum,we can acquire the information about the mineral composition,water content,mineral crystallinity and etc.In this passage,the soil from the surface of Hetao Plain has been analyzed,and in this case,we can obtain the information about the mineral composition,water content,mineral crystallinity and etc.Referring the features of local environment and climate,we could surmise the source of the minerals in soil and the environment where they formed.The result not only consummates the geological characterization of Hetao area,but also has great significance revealing mechanism of soil-formation in Hetao area.The result shows that the soil from surface of Hetao Plain is mainly composed by altered minerals,such as kaolinite,smectite,ledikite,muscovite etc,and is presumed to be from acidic rock mass of the Yinshan mountains.The passage also indicates that the Yinshan mountains have great impact on the formation of the soil on Hetao Plain in the aspect of climate,for example,though the climate of inner Mongolia is continental arid climate,enough rainfall and the substantial differences in mean annual precipitation ensure the relatively moist environment in this area,and make the sediments altered adequately,proposing new aspects about exploring the mechanism of the soil-formation in Hetao area..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 905 (2015)
Application of Fourier Transform Infrared Spectra (FTIR) Fingerprint in the Quality Control of Mineral Chinese Medicine Limonitum
LIU Sheng-jin, YANG Huan, WU De-kang, XU Chun-xiang, LIN Rui-chao, TIAN Jin-gai, and FANG Fang
In the present paper,the fingerprint of Limonitum (a mineral Chinese medicine) by FTIR was established,and the spectrograms among crude samples,processed one and the adulterant sample were compared．Eighteen batches of Limonitum samples from different production areas were analyzed and the angle cosine value of transmitIn the present paper,the fingerprint of Limonitum (a mineral Chinese medicine) by FTIR was established,and the spectrograms among crude samples,processed one and the adulterant sample were compared．Eighteen batches of Limonitum samples from different production areas were analyzed and the angle cosine value of transmittance (%)of common peaks was calculated to get the similarity of the FTIR fingerprints．The result showed that the similarities and the coefficients of the samples were all more than 0.90.The processed samples revealed significant differences compared with the crude one.This study analyzed the composition characteristics of Limonitum in FTIR fingerprint,and it was simple and fast to distinguish the crude,processed and the counterfeit samples.The FTIR fingerprints provide a new method for evaluating the quality of Limonitum..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 909 (2015)
Multidimensional Scaling Linear Regression Applied to FTIR Spectral Quantitative Analysis of Clinical Parameters of Human Blood Serum
CHEN Hua-zhou, SONG Qi-qing, SHI Kai, and JIA Zhen
In the present paper it was proposed to establish multidimensional scaling linear regression (MDS-MLR) models by combining multidimensional scaling (MDS) with multiple linear regression (MLR),in which MDS owns the ability of dimensionality reduction on spectral variables.Thus the informative spectral wavelengths can beIn the present paper it was proposed to establish multidimensional scaling linear regression (MDS-MLR) models by combining multidimensional scaling (MDS) with multiple linear regression (MLR),in which MDS owns the ability of dimensionality reduction on spectral variables.Thus the informative spectral wavelengths can be selected for each of the 4 clinical parameters (i.e.glucose,LDL cholesterol,triglycerides and urea) by MDS-MLR method,and the effect of spectral colinearity can be restrained,so that the calibration models can be optimized.Experiments showed that the MDS-MLR models will allow to produce appreciated modeling results when combined with the preprocessing method of moving average (MA).The optimized models were verified by the samples in validation set,and the validating correlation coefficients for each clinical parameter were all upper than 0.9.These results indicated that FTIR predicted values and the biochemical values of each clinical parameter were highly correlated,which demonstrated that MDS-MLR method has the potential of being applied to the FTIR spectroscopic analysis of human serum.FTIR rapid determination technology combined with the MDS-MLR modeling method is expected to realize the rapid assessment of human health and sub-health level..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 914 (2015)
Quantitative Approach to Melamine Detection in Egg White with Surface-Enhanced Raman Spectroscopy
WANG Qiao-hua, LIU Ya-li, MA Mei-hu, and WANG Hong
Due to the harmfulness of melamine to human,the quantitative detection of melamine in egg is very necessary.In the present study,the surface enhanced Raman spectra technology combined with chemometric analysis method was used to conduct melamine quantitative detection in egg white.Firstly,the melamine egg sample could Due to the harmfulness of melamine to human,the quantitative detection of melamine in egg is very necessary.In the present study,the surface enhanced Raman spectra technology combined with chemometric analysis method was used to conduct melamine quantitative detection in egg white.Firstly,the melamine egg sample could be got by the method of artificial feeding hens usingdifferent feeding formulation.Then the surface enhanced Raman spectra of egg white was determined using portable Raman spectroscopy (Opto Trace RamTracer-200) and Raman enhancement reagents,and the melamine content within the white eggs was measured with gas chromatography mass spectrometry technology.The software of Raman Analyzer was used for baseline correction of Raman spectra.The correlation coefficient method was used to choose 320 spectral variables from the surface enhanced Raman spectroscopy as input variables to establish partial least squares quantitative calibration model .And the peaks-decomposition method was used to establish peaks-decomposition quantitative calibration model.Both models selected 90 and 44 samples respectively as calibration sets and validation sets during model establishment,and both models achieved good prediction effect.The determination coefficient between predicted values of partial least squares quantitative calibration model and measured values of gas chromatography mass spectrometry was 0.856,and root mean square error of prediction was 1.547.The determination coefficient was 0.947 and RMSEP was 0.893 for the peaks-decomposition quantitative calibration model.This study demonstrated that the method can effectively quantitatively detect melamine in eggs.Testing a sample only takes 15 minutes,which can provide a new way for the melamine egg detection..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 919 (2015)
Raman Spectroscopic Study on the Determination of SO2-4 Concentration in Aqueous Solution under High Temperature and Pressure
TIAN Feng, ZHENG Hai-fei, and SUN Qiang
In the present work,the Raman spectra of SO2-4 ions in aqueous solutions were studied.The quantitative analysis shows that there is a significant correlation between the Raman intensity ratio(R) and the SO2-4 concentration.The SO2-4 concentration in aqueous solution at ambient temperature and pressure can be determinedIn the present work,the Raman spectra of SO2-4 ions in aqueous solutions were studied.The quantitative analysis shows that there is a significant correlation between the Raman intensity ratio(R) and the SO2-4 concentration.The SO2-4 concentration in aqueous solution at ambient temperature and pressure can be determined by the Raman intensity according to the linear fitting equation ｃ(SO2-4)=4.779 6R(r2=0.999 4).Furthermore,the research proves that the temperature and pressure will affect the relationship between the Raman intensity ratio and the concentration of SO2-4 ions.The quantitative equation for measuring the SO2-4 concentration in aqueous solution at high temperature and high pressure is ｃ(SO2-4)=4.779 6(R+1.469×10-4ΔT+1.340×10-4ΔP),where R is defined as the ratio of the SO2-4 ions band intensity to the OH stretching single band intensity,ΔT is the temperature relative to 23 ℃,ΔP is the pressure relative to 0.1 MPa,23 ℃≤T≤390 ℃,the concentration range of the SO2-4 ions is 0.5～1.5 mol·L-1,and the uncertainty of the equation is 6.5%.Raman spectroscopy can be used to measure the concentration of the Raman-active species in aqueous solutions..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 924 (2015)
Study on Raman Spectra of Some Animal and Plant Oils
WANG Xiang, and DAI Chang-jian
The spectral characteristics of different kinds of oil,either from plant seeds or animal fat,were studied with Raman spectroscopy.The experimental data were processed with the adaptive iteratively reweighted penalized least squares method to realize baseline correction,and provide evident information about their microsThe spectral characteristics of different kinds of oil,either from plant seeds or animal fat,were studied with Raman spectroscopy.The experimental data were processed with the adaptive iteratively reweighted penalized least squares method to realize baseline correction,and provide evident information about their microscopic world.The spectra were analyzed and compared with each other in three parts:the Raman spectra comparison among different samples of plant oils,the analysis of the animal fat and the comparison between plant oils and the animal fat.The differences among the oils were observed in the analysis,including Raman shift and Raman intensity differences.This study not only yields the spectral basis for distinguishing or recognizing the different edible oils,but also confirms that Raman spectroscopy is an effective tool for identifying different oils..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 929 (2015)
Characterizing Structural Composition of Dissolved and Particulate Organic Matter from Sediment Pore Water in a Urban River Using Excitation-Emission Matrix Fluorescence with Self-Organizing Map
YU Hui-bin, SONG Yong-hui, YANG Nan, DU Er-deng, PENG Jian-feng, and ZHI Er-quan
Excitation-emission matrix (EEM) fluorescence with self-organizing map was applied to characterize structural composition and spatial distribution of dissolved (DOM) and particulate (POM) organic matter from sediment pore water in a typical urban river.Ten sediment pore water samples were collected from the mainstream Excitation-emission matrix (EEM) fluorescence with self-organizing map was applied to characterize structural composition and spatial distribution of dissolved (DOM) and particulate (POM) organic matter from sediment pore water in a typical urban river.Ten sediment pore water samples were collected from the mainstream of Baitabuhe River in Shenyang City of northeast China,along a human impact gradient,i.e.river source,rural and urban regions.DOM and POM were extracted from the pore water,and their EEM fluorescence spectra were measured.f450/500 of DOM ranged from 1.82 to 1.91,indicating that DOM is mainly from microbial source;f450/500 of POM ranged from 1.42 to 1.68,suggesting that POM derived from land.Four components were identified from DOM and POM fractions by self-organizing map,which included tyrosine-like,tryptophan-like,fulvic-like and humic-like matters.Tyrosine-like originated from fresh and less degraded material with a high potential for oxidation,which was considered as representative components of DOM and POM.Tryptophan-like was associated with microbial byproduct-like material,and can indicate microbial activities.The abundance sum of all components in DOM is roughly 2 times more than that in POM.The mean relative abundance of tyrosine-like was more than 50%,while tryptophan-like was about 18.6%～23.1%.Abundance of fulvic-like was much more than that of humic-like,but they were only a small proportion of organic matter fractions.Based on principal component analysis,the characteristics of DOM and POM distinctly were distributed along river source,rural region and urban region,proving that the river was deeply influenced by human activity..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 934 (2015)
Analysis of Samples from Wastewater Treatment Plant and Receiving Waters Using EEM Fluorescence Spectroscopy
LI Wei-hua, LIU Yi-xin, WANG Wei, SHENG Guo-ping, YU Han-qing, and SHUAI Lei
The samples from several treatment units in wastewater treatment plant (WWTP) and different sample sites of receiving waters were characterized using excitation-emission matrix (EEM) fluorescence spectroscopy.After analyzed by parallel factor analysis (PARAFAC) method,the EEM fluorescence spectra of the principal compoThe samples from several treatment units in wastewater treatment plant (WWTP) and different sample sites of receiving waters were characterized using excitation-emission matrix (EEM) fluorescence spectroscopy.After analyzed by parallel factor analysis (PARAFAC) method,the EEM fluorescence spectra of the principal components and fluorescence intensity scores matrix were acquired.Results showed that protein-like and fulvic-like substances were the main components of the samples from the WWTP and the receiving water body.The intensity of protein-like fluorescence in the influent samples was rather strong,and those of the following samples decreased significantly.The protein-like fluorescence intensity of the samples was relatively weak from the upstream of receiving water body,while those of the samples increased significantly from the water body near the urban area.The protein-like fluorescence intensity of upstream samples of the WWTP disposal outlet was stronger than that of downstream in the receiving waters.The fluorescence intensity scores of protein-like substance could be correlated with the COD concentration of the samples and the correlation curves were established.The correlation coefficient of the WWTP samples was 0.930 and that of receiving water body samples was 0.913.The protein-like fluorescence could be used to evaluate the organic pollution of the samples.This study will provide a new method to investigate the operation status of WWTP and corresponding effect on the receiving water body..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 940 (2015)
Excitation-Emission Matrix Fluorescence Spectra Characteristics of DOM in Integrated Verical Flow Constructed Wetland for Treating Eutrophic Water
LI Shu-juan, GE Li-yun, and DENG Huan-huan
Three-dimensional fluorescence parameters can reflect classification,properties and content change of pollutants in wastewater treatment.In the present paper,by using three-dimensional fluorescence characteristic analysis,comparative analysis of conventional organic pollutants such as COD,TN and TP,and three dimensionaThree-dimensional fluorescence parameters can reflect classification,properties and content change of pollutants in wastewater treatment.In the present paper,by using three-dimensional fluorescence characteristic analysis,comparative analysis of conventional organic pollutants such as COD,TN and TP,and three dimensional fluorescence spectrum analysis,the classification and content of dissolved organic pollutants were identified.We studied fluorescence spectra,fluorescence peak (R.U.),fluorescence index (FI),humification index (HIX) of DOM’s four components in the entrance and effluent water and interstitial water,as well as the correlation between these four components and COD,TN and TP.The results showed that the position and intensity of the characteristic fluorescence peak center changed significantly before and after sewage treatment,indicating that the relative composition and content of the organic wastewater varied with wastewater treatment.Furthermore,the test results presented that humic-like composition was not degraded significantly,while protein-like composition was degraded significantly.And the protein-like component and COD,TN and TP presented significant positive correlation.This paper analyzed the fluorescence characteristics changes of dissolved organic matter in sewage treatment by using three-dimensional fluorescence spectrometry,and discussed the feasibility of three-dimensional fluorescence technique applied for description of dissolved organic pollutant degradation rule in the wastewater treatment process..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 946 (2015)
Fluorescence Resonance Energy Transfer Detection of Cobalt Ions by Silver Triangular Nanoplates and Rhodamine 6G
ZHANG Xiu-qing, PENG Jun, LING Jian, LIU Chao-juan, CAO Qiu-e, and DING Zhong-tao
In the present paper,the authors studied fluorescence resonance energy transfer (FRET) phenomenon between silver triangular nanoplates and bovine serum albumin (BSA)/Rhodamine 6G fluorescence complex,and established a fluorescence method for the detection of cobalt ions.We found that when increasing the silver triangulIn the present paper,the authors studied fluorescence resonance energy transfer (FRET) phenomenon between silver triangular nanoplates and bovine serum albumin (BSA)/Rhodamine 6G fluorescence complex,and established a fluorescence method for the detection of cobalt ions.We found that when increasing the silver triangular nanoplates added to certain concentrations of fluorescent bovine serum albumin (BSA) /Rhodamine 6G complex,the fluorescence of Rhodamine 6G would be quenched up to 80% due to the FRET between the quencher and donor.However,in the presence of cobalt ions,the disassociation of the fluorescent complex from silver triangular nanoplates occurred and the fluorescence of the Rhodamine 6G recovered.The recovery of fluorescence intensity rate (I/I0) has a good relationship with the cobalt ion concentration (cCO2+) added.Thus,the authors developed a fluorescence method for the detection of cobalt ions based on the FRET of silver triangular nanoplates and Rhodamine 6G..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 951 (2015)
Study on Therapeutic Effects of Ermiao Pill and Ermiao Pill Categorized Formula in Hyperuricemic Rats Using Spectroscopic Methods
CHEN Wei-jia, WU Yi, XU Chen, LIU Shu, WANG Wen-zhe, SONG Feng-rui, LIU Zhong-ying, and LIU Zhi-qiang
A stable mouse model of hyperuricemia was established by intraperitoneal injection of xanthine and oxonate,comparing the water extracts (containing crude drug 360 mg·mL-1) of Ermiao pill categorized formula (The ratio of atractylodes lancea to cortex phellodendri was 1:1,1:2 and 2:1,respectively) and Ermiao pill (A stable mouse model of hyperuricemia was established by intraperitoneal injection of xanthine and oxonate,comparing the water extracts (containing crude drug 360 mg·mL-1) of Ermiao pill categorized formula (The ratio of atractylodes lancea to cortex phellodendri was 1:1,1:2 and 2:1,respectively) and Ermiao pill (360 mg·mL-1) administered to different groups of animals continuously for two weeks and assessing the protection or treatment of drug on hyperuricemia.The xanthine oxidase (XOD) activities in serum and liver were detected by ultraviolet-visible spectroscopy at 570 nm wavelength,The results showed that as compared with each group,the XOD activity of the model group was significantly increased in serum (p<0.01),XOD activity showed no significant difference in liver (p>0.05),but compared with the model group,the XOD activity of each treatment group was significantly lower in serum and liver (p<0.01),especially for the group treated with Ermiao pill categorized formula with the ratio of Atractylodes lancea to Cortex Phellodendri being 1:2.The morphological changes of glomerular and tubular interstitial fibrosis were measured by Hematoxylin-eosin staining (HE staining) and Masson trichrome staining (Masson staining)for kidney paraffin sections.The results showed that the glomerular atrophy,vascular loops confusion,a certain degree of inflammatory cell infiltration,interstitial fibrosis and other phenomena appeared in the model group.Compared to model group,these pathological phenomena of the treatment groups were significantly improved.The area showed that compared with each group,the fibrosis of the model group was significantly increased (p<0.01 or p<0.05),but compared with Ermiao pill categorized formula,the differences for the group of Ermiao pill was lower (p<0.01),especially for the group treated with Ermiao pill categorized formula with the ratio of Atractylodes lancea to Cortex Phellodendri being 1:2.In this experiment,the damage of kidney and XOD activity serve as the index to evaluate the protection or treatment of drug on hyperuricemia,providing a scientific basis for the development of Ermiao pill categorized formula..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 956 (2015)
Using UV-Vis Absorbance for Characterization of Maturity in Composting Process with Different Materials
ZHAO Yue, WEI Yu-quan, LI Yang, XI Bei-dou, WEI Zi-min, WANG Xing-lei, ZHAO Zhi-nan, and DING Jei
The present study was conducted to assess the degree of humification in DOM during composting using different raw materials,and their effect on maturity of compost based on UV-Vis spectra measurements and chemometrics method.The raw materials of composting studied included chicken manure,pig manure,kitchen waste,lawn wThe present study was conducted to assess the degree of humification in DOM during composting using different raw materials,and their effect on maturity of compost based on UV-Vis spectra measurements and chemometrics method.The raw materials of composting studied included chicken manure,pig manure,kitchen waste,lawn waste,fruits and vegetables waste,straw waste,green waste,sludge,and municipal solid waste.During composting,the parameters of UV-Vis spectra of DOM,including SUVA254,SUVA280,E250/E365,E4/E6,E2/E4,E2/E6,E253/E203,E253/E220,A226～400,S275～295 and S350～400 were calculated,Statistical analysis indicated that all the parameter were significantly changed during composting.SUVA254 and SUVA280 of DOM were continuously increased,E250/E365 and E4/E6 were continuously decreased in DOM,while A226～400,S275～295 and S350～400 of DOM at the final stage were significantly different with those at other stages of composting.Correlation analysis indicated that the parameters were significantly correlated with each other except for E2/E4 and E235/E203.Furthermore,principal component analysis suggested that A226～400,SUVA254,S350～400,SUVA280 and S275～295 were reasonable parameters for assessing the compost maturity.To distinguish maturity degree among different composts,hierarchical cluster analysis,an integrated tool utilizing multiple UV-Vis parameters,was performed based on the data (A226～400,SUVA254,S350～400,SUVA280 and S275～295) of DOM derived from the final stage of composting.Composts from different sources were clustered into 2 groups.The first group included chicken manure,pig manure,lawn waste,fruits and vegetables waste,green waste,sludge,and municipal solid waste characterized by a lower maturity degree,and the second group contained straw waste and kitchen waste associated with a higher maturity degree.The above results suggest that a multi-index of UV-Vis spectra could accurately evaluate the compost maturity,and A226～400,SUVA254,S350～400,SUVA280 and S275～295 of DOM could serve as primary parameters when the compost maturity was assessed using UV-Vis spectra..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 961 (2015)
Mutual Effect on Determination of Gibberellins and Glyphosate in Groundwater by Spectrophotometry
ZHANG Li, CHEN Liang, and LIU Fei
In the present study,a spectrophotometry method for the simultaneous determination of gibberellins (GA3) and glyphosate in groundwater was established and optimized.In addition,the mutual effect on simultaneous determination of GA3 and glyphosate was studied.Based on the experiment,good linearity (R2>0.99) was obtaiIn the present study,a spectrophotometry method for the simultaneous determination of gibberellins (GA3) and glyphosate in groundwater was established and optimized.In addition,the mutual effect on simultaneous determination of GA3 and glyphosate was studied.Based on the experiment,good linearity (R2>0.99) was obtained for GA3 in the range of 0~20 and 0~100 μg and for glyphosate in the range of 0~8 and 5~15 μg.The method's detection limit (MDL) of GA3 and glyphosate was 0.48 and 0.82 μg,respectively;and the recovery rates of 15 to 150 μg GA3 and 3 to 10 μg glyphosate in all samples at a spiked level were 71.3%±1.9% and 98.4%±8.1%,respectively.No obvious influence of glyphosate (0～100 mg·L-1) on the recovery rates of GA3 was observed,but the presence of glyphosate could cause slight determination precision decrease of GA3.Meanwhile,adding 2 mg·L-1 GA3 can increase the recovery rate of glyphosate..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 966 (2015)
Trace Carbon Monoxide Detection with a Cavity Ring-Down Spectrometer
CHEN Bing, ZHOU Ze-yi, KANG Peng, LIU An-wen, and HU Shui-ming
A cavity ring-down spectrometer (CRDS) was built based on telecom distributed feedback (DFB) diode lasers.The ring down cavity was formed by mirrors of 99.997% reflectivity with a separation of 130 cm,with an empty ring down time of about 150 μs.A minimum detectable absorption coefficient of 5×10-12 cm-1 was obtaiA cavity ring-down spectrometer (CRDS) was built based on telecom distributed feedback (DFB) diode lasers.The ring down cavity was formed by mirrors of 99.997% reflectivity with a separation of 130 cm,with an empty ring down time of about 150 μs.A minimum detectable absorption coefficient of 5×10-12 cm-1 was obtained by averaging about 1 000 recorded spectra.The ring down cavity is thermo-isolated,and used as an interferometer to calibrate the recorded spectrum.A feedback control scheme was applied to step scan the laser frequency,successively matching each of the longitudinal modes of the cavity.By measuring the CO contents in a standard gas sample,the quantitative capability of the CRDS instrument was demonstrated,and a CO detection limit of 4 ppb was achieved.The instrument was applied to monitor the CO concentration in ambient air..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 971 (2015)
Research on Accuracy and Stability of Inversing Vegetation Chlorophyll Content by Spectral Index Method
JIANG Hai-ling, YANG Hang, CHEN Xiao-ping, WANG Shu-dong, LI Xue-ke, LIU Kai, and CEN Yi
Spectral index method was widely applied to the inversion of crop chlorophyll content.In the present study,PSR3500 spectrometer and SPAD-502 chlorophyll fluorometer were used to acquire the spectrum and relative chlorophyll content (SPAD value) of winter wheat leaves on May 2nd 2013 when it was at the jointing stage ofSpectral index method was widely applied to the inversion of crop chlorophyll content.In the present study,PSR3500 spectrometer and SPAD-502 chlorophyll fluorometer were used to acquire the spectrum and relative chlorophyll content (SPAD value) of winter wheat leaves on May 2nd 2013 when it was at the jointing stage of winter wheat.Then the measured spectra were resampled to simulate TM multispectral data and Hyperion hyperspectral data respectively,using the Gaussian spectral response function.We chose four typical spectral indices including normalized difference vegetation index (NDVI),triangle vegetation index (TVI),the ratio of modified transformed chlorophyll absorption ratio index(MCARI) to optimized soil adjusted vegetation index(OSAVI) (MCARI/OSAVI) and vegetation index based on universal pattern decomposition (VIUPD),which were constructed with the feature bands sensitive to the vegetation chlorophyll.After calculating these spectral indices based on the resampling TM and Hyperion data,the regression equation between spectral indices and chlorophyll content was established.For TM,the result indicates that VIUPD has the best correlation with chlorophyll (R2=0.819 7) followed by NDVI (R2=0.791 8),while MCARI/OSAVI and TVI also show a good correlation with R2 higher than 0.5.For the simulated Hyperion data,VIUPD again ranks first with R2=0.817 1,followed by MCARI/OSAVI (R2=0.658 6),while NDVI and TVI show very low values with R2 less than 0.2.It was demonstrated that VIUPD has the best accuracy and stability to estimate chlorophyll of winter wheat whether using simulated TM data or Hyperion data,which reaffirms that VIUPD is comparatively sensor independent.The chlorophyll estimation accuracy and stability of MCARI/OSAVI also works well,partly because OSAVI could reduce the influence of backgrounds.Two broadband spectral indices NDVI and TVI are weak for the chlorophyll estimation of simulated Hyperion data mainly because of their dependence on few bands and the strong influence of atmosphere,solar altitude,viewing angle of sensor,background and so on.In conclusion,the stability and consistency of chlorophyll estimation is equally important to the estimation accuracy by spectral index method.VIUPD introduced in the study has the best performance to estimate winter wheat chlorophyll,which illustrates its potential ability in the area of estimating vegetation biochemical parameters..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 975 (2015)
Impact of Vegetation Structure on Drought Indices Based on MODIS Spectrum
DU Ling-tong, TIAN Qing-jiu, and WANG Lei
The drought indices based on MODIS spectral reflectance data are widely used for drought characterization and monitoring in agricultural context.Based on the PROSAIL model and MODIS observational data in Shandong in 2010,the present paper studied the impact of vegetation structure of leaf area index and physiological gThe drought indices based on MODIS spectral reflectance data are widely used for drought characterization and monitoring in agricultural context.Based on the PROSAIL model and MODIS observational data in Shandong in 2010,the present paper studied the impact of vegetation structure of leaf area index and physiological growth cycle on MODIS spectral drought index.The results showed that the reflectance of three MODIS bands in spectrum of near-infrared and shortwave infrared changes significantly with leaf water content of vegetation.Therefore,the five kinds of MODIS spectral drought index constructed by those MODIS bands can be used to monitor the leaf water content of vegetation.However,all drought indices are affected by leaf area index.In general,the impact is serious in the case of low LAI values and is weakened with the increase in LAI value.The study found that physiological vegetation growth cycle also affects the magnitude of MODIS spectral drought indices.In conclusion,the impact of vegetation structure must be carefully considered when using MODIS spectral drought indices to monitor drought.The conclusion of this study provides a theoretical basis for remote sensing of drought monitoring..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 982 (2015)
Study on the Reliability Assessment Method of Heavy Vehicle Gearbox Based on Spectrometric Analysis
BAO Ke, ZHANG Zhong, CAO Yuan-fu, and CHEN Yi-jie
Spectrometric oil analysis is of great importance for wear condition monitoring of gearbox.In this context,the contents of main elements compositions in the bench test of heavy vehicle gearbox are obtained by atomic emission spectrometric oil analysis first.Then correlation analysis of the test data and wearing mechaniSpectrometric oil analysis is of great importance for wear condition monitoring of gearbox.In this context,the contents of main elements compositions in the bench test of heavy vehicle gearbox are obtained by atomic emission spectrometric oil analysis first.Then correlation analysis of the test data and wearing mechanism analysis are carried out to get the metal element which could be used to describe the wearing and failure of the gearbox.The spectrometric data after filling/changing oil are corrected,and the laws of the contents of main elements compositions during tests are expressed as linear functions.After that,the reliability assessment is executed with considering the degradation law and discreteness of test data,in which the mean and standard deviation of normal distribution of spectrometric oil data at each time point are adopted.Finally,the influences of the threshold are discussed.It has been proved that the contents of metal element Cu,which is got by spectrometric oil analysis of different samples,could be used to assess the reliability of heavy vehicle gearbox.The reason is that the metal element Cu is closely related to the general wear state of gearbox,and is easy to be measured.When the threshold of Cu content is treated as a constant,bigger threshold means higher reliability at the same time,and the mean value of threshold has significant impact on the reliability assessment results as R>0.9.When the threshold is treated as a random variable,bigger dispersion of threshold means smaller slope of reliability against time,and also means lower reliability of gearbox as R>0.9 at the same time.In this study,the spectrometric oil analysis and probability statistics are used together for the reliability assessment of gear box,which extends the application range of spectrometric analysis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 987 (2015)
Multi-Target Recognition of Internal and External Defects of Potato by Semi-Transmission Hyperspectral Imaging and Manifold Learning Algorithm
HUANG Tao, LI Xiao-yu, JIN Rui, KU Jing, XU Sen-miao, XU Meng-ling, WU Zhen-zhong, and KONG De-guo
The present paper put forward a non-destructive detection method which combines semi-transmission hyperspectral imaging technology with manifold learning dimension reduction algorithm and least squares support vector machine (LSSVM) to recognize internal and external defects in potatoes simultaneously.Three hundred fifThe present paper put forward a non-destructive detection method which combines semi-transmission hyperspectral imaging technology with manifold learning dimension reduction algorithm and least squares support vector machine (LSSVM) to recognize internal and external defects in potatoes simultaneously.Three hundred fifteen potatoes were bought in farmers market as research object,and semi-transmission hyperspectral image acquisition system was constructed to acquire the hyperspectral images of normal external defects (bud and green rind) and internal defect (hollow heart) potatoes.In order to conform to the actual production,defect part is randomly put right,side and back to the acquisition probe when the hyperspectral images of external defects potatoes are acquired.The average spectrums (390~1 040 nm) were extracted from the region of interests for spectral preprocessing.Then three kinds of manifold learning algorithm were respectively utilized to reduce the dimension of spectrum data,including supervised locally linear embedding (SLLE),locally linear embedding (LLE) and isometric mapping (ISOMAP),the low-dimensional data gotten by manifold learning algorithms is used as model input,Error Correcting Output Code (ECOC) and LSSVM were combined to develop the multi-target classification model.By comparing and analyzing results of the three models,we concluded that SLLE is the optimal manifold learning dimension reduction algorithm,and the SLLE-LSSVM model is determined to get the best recognition rate for recognizing internal and external defects potatoes.For test set data,the single recognition rate of normal,bud,green rind and hollow heart potato reached 96.83%,86.96%,86.96% and 95% respectively,and he hybrid recognition rate was 93.02%.The results indicate that combining the semi-transmission hyperspectral imaging technology with SLLE-LSSVM is a feasible qualitative analytical method which can simultaneously recognize the internal and external defects potatoes and also provide technical reference for rapid on-line non-destructive detecting of the internal and external defects potatoes..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 992 (2015)
Detection of Carbon Dioxide Concentration in Soil Profile Based on Nondispersive Infrared Spectroscopy Technique
TU Zhi-hua, ZHAO Yang, ZHENG Li-wen, JIA Guo-dong, CHEN Li-hua, and YU Xin-xiao
In order to explore the variation of CO2 concentration and soil respiration in soil profile,the nondispersive infrared (NDIR) spectroscopy technique was applied to continually estimate the soil CO2 concentration in different soil layers (the humus horizon,A-,B-,C-horizon) in situ.The main instrument used in this experiIn order to explore the variation of CO2 concentration and soil respiration in soil profile,the nondispersive infrared (NDIR) spectroscopy technique was applied to continually estimate the soil CO2 concentration in different soil layers (the humus horizon,A-,B-,C-horizon) in situ.The main instrument used in this experiment was silicon-based nondispersive infrared sensor,which could work in severe environment.We collected the measurement value by NDIR spectroscopy technique throughout 2013.The values of soil carbon flux in different soil layers were calculated based on the model of gradient method and calibrated by measuring with an automated soil CO2 efflux system (LI-8100).The results showed that:a vertical gradient for the carbon dioxide concentration in soil profile was found,and the concentration was highest in the deepest soil horizon.Moreover,A linear correlation between the soil CO2 effluxes was calculated based on model and measurement,and the model prediction correlation coefficient was 0.906 9,0.718 5,0.838 2,and 0.903 0 in the H-,A-,B-,and C-horizon,respectively.The roots of mean square error (RMSE) were 0.206 7,0.104 1,0.015 6,and 0.009 6 in the H-,A-,B-,and C-horizon,respectively.These results suggest that the gradient method based on the NDIR spectroscopy technique can be successfully used to measure soil CO2 efflux in different soil layers,which reveal that diffusion and convection transport CO2 between the soil layers.It is a promising sensor for detecting CO2 concentration in soil profile,providing the basic data for calculating the global carbon in soil profile..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 997 (2015)
Three-Iindex-Value Method for Rapid Screening Unqualified Vegetable Oil
HE Wen-xuan, HONG Gui-shui, FANG Run, CAI Xian-chun, and HUANG Sheng
In the present study,by measuring the A3 005 (representing unsaturation),A985 (representing conjugated fatty acids),A960+A985 (representing trans-fatty acid ) of southern common vegetable oils (peanut oil,corn oil,canola oil,soybean oil,sunflower oil,tea seed oil and olive oil),“waste oil” and overdue vegetable oils,thIn the present study,by measuring the A3 005 (representing unsaturation),A985 (representing conjugated fatty acids),A960+A985 (representing trans-fatty acid ) of southern common vegetable oils (peanut oil,corn oil,canola oil,soybean oil,sunflower oil,tea seed oil and olive oil),“waste oil” and overdue vegetable oils,the pass-setting-range of these three index values for the vegetable oils was obtained.On this basis,a method for rapid screening unqualified vegetable oil (expired,adding low-cost oil,adding “waste oil”) was established.The method effectively improved the monitoring efficiency of vegetable oil.With this method of screening a number of suspected substandard oils were proved unqualified by determination of fatty acid composition and 11,12,13,17 fatty acid content.Through the combination of several detection methods,the causes for disqualification of vegetable oils can be further inferred..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1001 (2015)
Biosorption of Radionuclide Uranium by Deinococcus Radiodurans
Yang Jie, Dong Faqin, Dai Qunwei, Liu Mingxue, Nie Xiaoqin, Zhang Dong, Ma Jialin, and Zhou Xian
As a biological adsorbent,Living deinococcus radiodurans was used for removing radionuclide uranium in the aqueous solution.The effect factors on biosorption of radionuclide uranium were researched in the present paper,including solution pH values and initial uranium concentration.Meanwhile,the biosorption mechanism waAs a biological adsorbent,Living deinococcus radiodurans was used for removing radionuclide uranium in the aqueous solution.The effect factors on biosorption of radionuclide uranium were researched in the present paper,including solution pH values and initial uranium concentration.Meanwhile,the biosorption mechanism was researched by the method of FTIR and SEM/EDS.The results show that the optimum conditions for biosorption are as follows:pH=5,ｃ0=100 mg·L-1 and the maximum biosorption capacity is up to 240 mgU·g-1.According to the SEM results and EDXS analysis,it is indicated that the cell surface is attached by lots of sheet uranium crystals,and the main biosorpiton way of uranium is the ion exchange or surface complexation.Comparing FTIR spectra and FTIR fitting spectra before and after biosorption,we can find that the whole spectra has a certain change,particularly active groups (such as amide groups of the protein,hydroxy,carboxyl and phosphate group) are involved in the biosorption process.Then,there is a new peak at 906 cm-1 and it is a stretching vibration peak of UO2+2.Obviously,it is possible that as an anti radiation microorganism,deinococcus radiodurans could be used for removing radionuclide uranium in radiation environment..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1010 (2015)
Retrieving Chromophoric Dissolved Organic Matter in Guanting Reservoir Based on in-situ Measured Reflectance Data
ZHOU Ya-ming, LI Jun-sheng, SHEN Qian, and ZHANG Fang-fang
In the present paper,Guanting Reservoir located in Zhangjiakou City,Hebei province and Yanqing District,Beijing,was selected as the study area,and Chromophoric dissolved organic matter (CDOM) content (represented by the CDOM absorption coefficient at 440 nm,aCDOM(440)) was inverted through semi-analytical method and emIn the present paper,Guanting Reservoir located in Zhangjiakou City,Hebei province and Yanqing District,Beijing,was selected as the study area,and Chromophoric dissolved organic matter (CDOM) content (represented by the CDOM absorption coefficient at 440 nm,aCDOM(440)) was inverted through semi-analytical method and empirical method.The data used in this paper include the spectral data (Rrs(λ)) collected on October 26,2013 over Guanting Reservoir and aCDOM(λ) measured in the laboratory.A semi-analytical method (QAA-CDOM) was validated and improved accordingly.The inversion result accuracy of QAA-CDOM was not bad,the root-mean-square error (RMSE) was 0.10 and the mean relative error (σ) was 10.8%.The QAA-CDOM method was improved by recalculating the value of Q (the ratio of upwelling irradiance to upwelling radiance just below the water surface) by the field spectral data to replace the fixed value.After this improvement,the inversion accuracy was slightly improved,with RMSE of 0.09 and σ of 10.2%.After that,four band ratios were used in linear regression with aCDOM(440) to build empirical inversion models.The results showed that the performance of the model based on Rrs(531)/Rrs(551) was the best,with R2 of 0.63.The RMSE and σ of the aCDOM(440) result inverted by the empirical method were 0.08 and 8.8% respectively.The empirical method was of higher precision than that of the semi-analytical method,but the bands and coefficients used in the empirical method need to be calibrated by concurrently measured data in each study area.On the contrary,semi-analytical method does not need calibration,and is easier to be applied..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1015 (2015)
Determination of Soluble Solid Content in Strawberry Using Hyperspectral Imaging Combined with Feature Extraction Methods
DING Xi-bin, ZHANG Chu, LIU Fei, SONG Xing-lin, KONG Wen-wen, and HE Yong
Hyperspectral imaging combined with feature extraction methods were applied to determine soluble sugar content (SSC) in mature and scatheless strawberry.Hyperspectral images of 154 strawberries covering the spectral range of 874～1 734 nm were captured and the spectral data were extracted from the hyperspectral images,aHyperspectral imaging combined with feature extraction methods were applied to determine soluble sugar content (SSC) in mature and scatheless strawberry.Hyperspectral images of 154 strawberries covering the spectral range of 874～1 734 nm were captured and the spectral data were extracted from the hyperspectral images,and the spectra of 941～1 612 nm were preprocessed by moving average (MA).Nineteen samples were defined as outliers by the residual method,and the remaining 135 samples were divided into the calibration set (n=90) and the prediction set (n=45).Successive projections algorithm (SPA),genetic algorithm partial least squares (GAPLS) combined with SPA,weighted regression coefficient (Bw) and competitive adaptive reweighted sampling (CARS) were applied to select 14,17,24 and 25 effective wavelengths,respectively.Principal component analysis (PCA) and wavelet transform (WT) were applied to extract feature information with 20 and 58 features,respectively.PLS models were built based on the full spectra,the effective wavelengths and the features,respectively.All PLS models obtained good results.PLS models using full spectra and features extracted by WT obtained the best results with correlation coefficient of calibration (rc) and correlation coefficient of prediction (rp) over 0.9.The overall results indicated that hyperspectral imaging combined with feature extraction methods could be used for detection of SSC in strawberry..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1020 (2015)
Research on Oil Sands Spectral Characteristics and Oil Content by Remote Sensing Estimation
YOU Jin-feng, XING Li-xin, PAN Jun, SHAN Xuan-long, LIANG Li-heng, and FAN Rui-xue
Visible and near infrared spectroscopy is a proven technology to be widely used in identification and exploration of hydrocarbon energy sources with high spectral resolution for detail diagnostic absorption characteristics of hydrocarbon groups.The most prominent regions for hydrocarbon absorption bands are 1 740～1 780Visible and near infrared spectroscopy is a proven technology to be widely used in identification and exploration of hydrocarbon energy sources with high spectral resolution for detail diagnostic absorption characteristics of hydrocarbon groups.The most prominent regions for hydrocarbon absorption bands are 1 740～1 780,2 300～2 340 and 2 340～2 360 nm by the reflectance of oil sands samples.These spectral ranges are dominated by various C—H overlapping overtones and combination bands.Meanwhile,there is relatively weak even or no absorption characteristics in the region from 1 700 to 1 730 nm in the spectra of oil sands samples with low bitumen content.With the increase in oil content,in the spectral range of 1 700~1 730 nm the obvious hydrocarbon absorption begins to appear.The bitumen content is the critical parameter for oil sands reserves estimation.The absorption depth was used to depict the response intensity of the absorption bands controlled by first-order overtones and combinations of the various C—H stretching and bending fundamentals.According to the Pearson and partial correlation relationships of oil content and absorption depth dominated by hydrocarbon groups in 1 740～1 780,2 300～2 340 and 2 340～2 360 nm wavelength range,the scheme of association mode was established between the intensity of spectral response and bitumen content,and then unary linear regression(ULR) and partial least squares regression (PLSR) methods were employed to model the equation between absorption depth attributed to various C—H bond and bitumen content.There were two calibration equations in which ULR method was employed to model the relationship between absorption depth near 2 350 nm region and bitumen content and PLSR method was developed to model the relationship between absorption depth of 1 758,2 310,2 350 nm regions and oil content.It turned out that the calibration models had good predictive ability and high robustness and they could provide the scientific basis for rapid estimation of oil content in oil sands in future..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1025 (2015)
Research Progress in Analytical Technology for Heavy Metals in Atmospheric Particles
WANG Yu-jie, TU Zhen-quan, ZHOU Li, CHI Yong-jie, and LUO Qin
Atmospheric particles have become the primary atmospheric pollutions,of which the heavy metals,owing to non-degradability and hysteresis,a serious threat to human life and natural environment,have become a hot research issue currently.The analytical methods of heavy metals in atmospheric particles are summarized in theAtmospheric particles have become the primary atmospheric pollutions,of which the heavy metals,owing to non-degradability and hysteresis,a serious threat to human life and natural environment,have become a hot research issue currently.The analytical methods of heavy metals in atmospheric particles are summarized in the present review,including atomic absorption spectrometry,inductively coupled plasma atomic emission spectrometry,inductively coupled plasma mass spectrometry,neutron activation analysis,fluorescence spectrometry,glow discharge atomic emission spectrometry,microwave plasma atomic emission spectrometry,and laser induced breakdown spectroscopy,and some proposals are tried to make for improving the shortcomings of these technologies:continuum source Atomic absorption spectrometry for simultaneously measuring multi-elements,atomic emission spectrometry for direct determination of particulates,high resolution laser ablation inductively coupled plasma mass spectrometry for determination of solid samples,low scattering synchrotron fluorescence spectrum for determination of atmospheric particulate matter and k0 neutron activation analysis for determination of radioactive elements in the troposphere.Analysis techniques of heavy metals in atmospheric particulate matter are promoted to develop toward being real-time,fast,low-detection-limit,direct-measurement and simple-operation due to the spatial and temporal distribution difference of the heavy metals in atmospheric particles and human requirement for improvement of ambient air quality as well as rapid development of modern instrument science and technology..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1030 (2015)
Influence of Flame Emission Spectroscopy on K measurement Using Laser Induced Breakdown Spectroscopy
ZHANG Zhi-hao, SONG Qiang, Zeyad T.Alwahabi, and YAO Qiang
During the combustion of coal or biomass,the inherent alkali metals in the fuel will be released to the gas phase.The released alkali species condensed during the cooling of the flue gas,which may subsequently cause problems with ash deposition and corrosion in thermal fuel conversion systems.Laser Induced Breakdown SpDuring the combustion of coal or biomass,the inherent alkali metals in the fuel will be released to the gas phase.The released alkali species condensed during the cooling of the flue gas,which may subsequently cause problems with ash deposition and corrosion in thermal fuel conversion systems.Laser Induced Breakdown Spectroscopy (LIBS) is an effective technique to measure the alkali species in the plume of burning coal or biomass.In this study,an LIBS experimental system with a flat flame burner was set up,and the Flame Emission Spectroscopy (FES) and LIBS of K in the flat flame environment were measured using different ICCD gate-width times.The experimental results revealed that with the same ICCD gate-width time,the LIBS intensity of K was higher than the FES intensity of K in the flat flame.With the increase of the ICCD gate-width time,both intensities increased,but their increase rates were different:the increase rate of the LIBS intensity of K was firstly fast then became slow,but the increase rate of the FES intensity of K was constant.Furthermore,the intensity ratio of LIBS to FES of K increased monotonically with the ICCD gate-width time in the range of 0～8 μs,until reaching approximately 4.Then,further increasing the ICCD gate-width time,such ratio decreased slowly with an asymptote value of 1.After analyzing the influences of the FES on the LIBS measurement of K in a flame condition,it is proposed that to minimize such influence,the optimization of the ICCD gate-width time was necessary,which maximized the intensity ratio of LIBS to FES of K and facilitated the measurement accuracy of K in the flame environment using LIBS..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1033 (2015)
Study on Content Determination of Lead and Arsenic in Four Traditional Tibetan Medicine Prescription Preparations by Wet Digestion Flow Injection-Hydride Generation-Atomic Absorption Spectrometry
ZHENG Zhi-yuan, DU Yu-zhi, ZHANG Ming, YU Ming-jie, LI Cen, YANG Hong-xia, ZHAO Jing, XIA Zheng-hua, and WEI Li-xin
Four common traditional tibetan medicine prescription preparations “Anzhijinghuasan,Dangzuo,Renqingchangjue and Rannasangpei” in tibetan areas were selected as study objects in the present study.The purpose was to try to establish a kind of wet digestion and flow injection-hydride generation-atomic absorption spectromeFour common traditional tibetan medicine prescription preparations “Anzhijinghuasan,Dangzuo,Renqingchangjue and Rannasangpei” in tibetan areas were selected as study objects in the present study.The purpose was to try to establish a kind of wet digestion and flow injection-hydride generation-atomic absorption spectrometry (FI-HAAS) associated analysis method for the content determinations of lead and arsenic in traditional tibetan medicine under optimized digestion and measurement conditions and determine their contents accurately.Under these optimum operating conditions,experimental results were as follows.The detection limits for lead and arsenic were 0.067 and 0.012 μg·mL-1 respectively.The quantification limits for lead and arsenic were 0.22 and 0.041 μg·mL-1 respectively.The linear ranges for lead and arsenic were 25～1 600 ng·mL-1 (r=0.999 5) and 12.5～800 ng·mL-1(r=0.999 4) respectively.The degrees of precision(RSD) for lead and arsenic were 2.0% and 3.2% respectively.The recovery rates for lead and arsenic were 98.00%～99.98% and 96.67%～99.87% respectively.The content determination results of lead and arsenic in four traditional tibetan medicine prescription preparations were as follows.The contents of lead and arsenic in Anzhijinghuasan are 0.63～0.67 μg·g-1 and 0.32～0.33 μg·g-1in Anzhijinghuasan,42.92～43.36 μg·g-1 and 24.67～25.87 μg·g-1 in Dangzuo,1 611.39～1 631.36 μg·g-1 and 926.76～956.52 μg·g-1 in Renqing Changjue,and 1 102.28～1 119.27 μg·g-1 and 509.96～516.87 μg·g-1 in Rannasangpei,respectively.This study established a method for content determination of lead and arsenic in traditional tibetan medicine,and determined the content levels of lead and arsenic in four tibetan medicine prescription preparations accurately.In addition,these results also provide the basis for the safe and effective use of those medicines in clinic..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1037 (2015)
Determination of Arsenic in Food Package Aluminum by Ultrasound Assisted Solid Phase Extraction/ICP-AES
QIN Wen-xia, GONG Qi, LI Min, DENG Li-xin, MO Li-shu, and LI Yan-lin
Determination of arsenic in pure aluminum by inductively coupled plasma atomic emission spectrometry was interfered by aluminum matrix.The experiment showed that when the mass concentration of Al was greater than or equal to 5 000 times the As in the test solution,the measurement error was greater than 5%.In order to eDetermination of arsenic in pure aluminum by inductively coupled plasma atomic emission spectrometry was interfered by aluminum matrix.The experiment showed that when the mass concentration of Al was greater than or equal to 5 000 times the As in the test solution,the measurement error was greater than 5%.In order to eliminate the interference,strong acid cation exchange fiber (SACEF) was used as solid phase extraction agent to adsorb Al3+.The extraction conditions included amount of SACEF,extraction time,temperature and pH were investigated.The optimal extraction conditions were that 0.900 0 g SACEF was used to extract the aluminum from the sample solution of pH 2.0 at 55 ℃ for 5 min with the ultrasonic assist,and in this case,the arsenic in the form of arsenic acid was not extracted and left in the solution for the determination.The results showed that after treating 10.00 mL test solution containing 1.00 μg arsenic and 20.0 mg aluminum,arsenic did not lose.The mass concentration of residual aluminum in the raffinate was about 2 000 times the As,which had not interfered the determination of arsenic.The detection limit (3 s) was 0.027 μg·mL-1 and quantification limit (10 s) was 0.091 μg·mL-1.The proposed method was successfully applied to the separation and determination of arsenic in the synthetic samples,the aluminum cans and the barbecue aluminum foil.Recovery was in the range of 98.3%~105% and RSD (n=3) was in the range of 0.1%~4.3%.The results showed that the content of arsenic in the aluminum cans and the aluminum barbecue foil was below the limited value of national standard (GB/T 3190—2008)..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1043 (2015)
Determination of Trace Germanium in Plant Samples by Dry Ashing-Atomic Fluorescence Spectrometry
CHEN Hai-jie, YU Zhao-shui, BAI Jin-feng, LI Qing-xia, LIU Ya-xuan, BO Wei, and ZHANG Qin
To reduce the limit of detection (LOD) and allow the accurate determination of Ge,a dry ashing method was performed to enrich the Ge in plant samples.A method for the determination of trace Ge in plant samples by HG-AFS was established.Study of the effect of temperature on the ashing of plant samples showed that no volTo reduce the limit of detection (LOD) and allow the accurate determination of Ge,a dry ashing method was performed to enrich the Ge in plant samples.A method for the determination of trace Ge in plant samples by HG-AFS was established.Study of the effect of temperature on the ashing of plant samples showed that no volatile loss of Ge occurred even at 900 ℃.Additional experiments indicated that a 4 h burning process at 600 ℃ would be sufficient to fully ash the plant samples.Various digestion methods (involving nitric acid,hydrofluoric acid,and sulfuric acid digestion methods) for ashed samples were investigated.High-temperature ashing with large sample weights was used,which could reduce the reagent doses and the method’s LOD effectively and simultaneously,the precision of the method was improved.The method’s LOD was 0.27 ng·g-1,and the relative standard deviation was 3.99%～6.81%.Verified with national biological reference materials (grade Ⅰ),the proposed method was accurate and reliable..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1048 (2015)
Determination of Mineral Elements in Choerospondias Axillaris and Its Extractives by ICP-AES
ZHAI Yu-xin, CHEN Jun, LI Ti, LIU Ji-yan, WANG Xie-yi, CHENG Chao, and LIU Cheng-mei
Nine elements in Choerospondias axillaris flesh,peels,aqueous extractives and gastric digesta were determined by the inductively coupled plasma atomic emission spectrometry (ICP-AES) in the present study.The results showed that the contents of Fe,Ca,Zn,Mn,Al,Mg,Cu,K and P in the flesh were 27.37,269.88,1.51,2.45,1.95,1Nine elements in Choerospondias axillaris flesh,peels,aqueous extractives and gastric digesta were determined by the inductively coupled plasma atomic emission spectrometry (ICP-AES) in the present study.The results showed that the contents of Fe,Ca,Zn,Mn,Al,Mg,Cu,K and P in the flesh were 27.37,269.88,1.51,2.45,1.95,195.30,2.45,2 970.11,and 133.94 μg·g-1,respectively.They are lower than that in the peels,about 40.31%,11.70%,21.68%,4.27%,10.58%,15.76%,68.72%,42.04%,and 22.59%,respectively.For microwave assistant extraction,the release rate of Mn was highest (81.68%),while Fe was lowest (4.42%) in the flesh.The release rate of Zn was the highest (79.00%),while that of Al was the lowest (4.94%) in the peels.Except Fe,Cu and Zn,the release rates of the other elements in flesh were higher than those in the peels.After gastric digestion,the release rates of nine elements were 3.25%~87.51% in the flesh and 7.11%~50.69% in the peels.The release rates of minerals in the flesh were found to be higher than those in the peels except Fe and Cu.Microwave assistant extraction can more efficiently release Fe,Ca,Mn,Mg and K from the flesh than the gastric digestion do.While gastric digestion had a significant effect on the peels,the release rates of elements,except Zn,were higher than those in microwave assistant extraction.Therefore,the difference of distribution and release of mineral elements between peels and flesh of Choerospondias axillaris was understood,which will provide a positive guide for further study of bioavailability of minerals for human body..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1052 (2015)
Identification of Chinese Traditional Medicine Cistanches Herba from Different Places by HPLC-ESI-MS and FTIR Methods
ZHOU Ye, LI Wei, HAN Li-feng, SONG Xin-bo, LI Pei-fu, WANG Rui, and ZHANG Bo-li
Five samples of Cistanches Herba from different places were analyzed by HPLC-ESI-MS and FTIR methods.The effective compositions in Cistanches Herba including cistanoside A,echinacoside,acteoside ,isoacteoside,2’-actylacteoside,cistanoside C and tubluoside B were determined by HPLC-MS.The common peak ratio and variant pFive samples of Cistanches Herba from different places were analyzed by HPLC-ESI-MS and FTIR methods.The effective compositions in Cistanches Herba including cistanoside A,echinacoside,acteoside ,isoacteoside,2’-actylacteoside,cistanoside C and tubluoside B were determined by HPLC-MS.The common peak ratio and variant peak ratio were calculated by FTIR spectroscopy of the five samples and the dual index sequence of common peak ratio and variant peak ratio were established.The results showed that the evaluation results of the samples by the two methods were the same.The general fake plant Cynomorii Herba could be identified by FTIR.HPLC-ESI-MS,which has high sensitivity and rapid determination procedure,can be used to evaluate quality of Cistanches Herba by quantitative analysis of the primary compositions.FTIR is a non-destructive analysis method without complicated extraction and separation procedures to the samples.The absorption strength and the absorption shape were the synergistic effect of the functional groups and the nestification of the components in Cistanches Herba.The provided method has some advantages such as rapid analysis process,good reproducibility,non-destructive,small quantity of sample,simple treatment,good specificity,low-cost and environment-friendly.The method meets the trend of complex analysis and whole analysis for the Chinese medicines.Combination of FTIR and HPLC-ESI-MS was a good method for identification and evaluation of quality of Chinese medicines..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1056 (2015)
Study on Speciation Analysis and Ecological Risk Assessment of Heavy Metals in Surface Sediments in Gansu,Ningxia and Inner Mongolia Sections of the Yellow River in Wet Season with HR-ICP-MS
MA Xiao-ling, LIU Jing-jun, ZUO Hang, HUANG Fang, and LIU Ying
In order to continuously study the contents,pollution condition and potential ecological risk of heavy metals in surface sediments in Gansu,Ningxia and Inner Mongolia sections of the Yellow River in wet seasons in different years,the speciation analysis of 9 kinds of heavy metals including Cd,Pb,Cr,Ni,Cu,V,Co,Zn and MnIn order to continuously study the contents,pollution condition and potential ecological risk of heavy metals in surface sediments in Gansu,Ningxia and Inner Mongolia sections of the Yellow River in wet seasons in different years,the speciation analysis of 9 kinds of heavy metals including Cd,Pb,Cr,Ni,Cu,V,Co,Zn and Mn,pollution condition and potential ecological risk of heavy metals in surface sediments from 10 sampling sites like Baotoufuqiao (S2),Shizuishantaolezhen (S6) and Wujinxia (S9) in Gansu,Ningxia and Inner Mongolia sections of the Yellow River in 2012 wet season were studied with BCR sequential extraction and high resolution inductively coupled plasma-mass spectrometry (HR-ICP-MS) based on our previous works.The results implied that the order of heavy metals average contents in the 10 sediment samples were the same:Mn＞V＞Zn＞Cr＞Cu＞Ni＞Pb＞Co＞Cd.In the sediments,heavy metals mainly existed in the form of residual fraction,which indicated that the bioavailability or environmental impact was low.Results of geo-accumulation indices (Igeo) showed that ICdgeo was the largest among the heavy metals with the strongest pollution,while IMngeo was the smallest.Enrichment factor (EF) indicated that only Cd and Cu were enriched at some sampling sites.In S5,because EFCd reached 4.69,Cd was affected by human activities obviously and the result was consistent with Igeo.Potential ecological risk index (RI) implied that the RI values in S1,S2 and S5 were between 150 and 300,which belonged to moderate polluting degree,while others were less than 150,belonging to light pollution degree.The results of this paper could not only provide reliable experimental data and theoretical basis for the relevant departments,but also supply the technical support for constructing mathematics model of sediments-pollutants transport,systematically researching the migration and transformation rule of persistent toxic substances and environmental assessment in these reaches..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1062 (2015)
Research on Test Method of Metallic Element Contained in Tea Based on EDXRF Technique
QIN Xu-lei, LI Ye, SONG Zhong-hua, WANG Guo-zheng, LI Shen, SHAN Gao-feng, and DUANMU Qing-duo
As it has been certified by experimental testing that when using the energy-dispersive X-ray fluorescence (EDXRF) method to analyze the metallic elements contained in the tea the energy segment of effective X-ray fluorescence photons is located between 3 and 16 keV.Accordingly the spectral correction element is targeteAs it has been certified by experimental testing that when using the energy-dispersive X-ray fluorescence (EDXRF) method to analyze the metallic elements contained in the tea the energy segment of effective X-ray fluorescence photons is located between 3 and 16 keV.Accordingly the spectral correction element is targeted at the copper elements located near the energy center(8 keV).The copper elements are also used as the picketage to be the standard curve.In the energy segment of effective X-ray fluorescence photons contained in the tea 1.25 mg·kg-1 of the average detection limit was obtained by using the spiked method to analyze four elements of copper,iron,zinc and lead.Compared with the flame atomic absorption spectrum(FAAS),the actual relative error of the tested value by EDXRF is less than 6%,and the relative standard deviation is less than 5%.The result by T test shows that p>0.05.The conclusions are that there are no statistically significant differences between EDXRF and FAAS.The measured results gained by the two methods agree with each other.And EDXRF can be used thoroughly to test the metal contents contained in the tea.The result shows that it is feasible to test the metallic contents contained in the tea by EDXRF,and its measured result can meet the requirements of field testing and analysis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1068 (2015)
Chemical Components,Mercury Coordination Structure and Micro-Morphology of Tibetan Medicine Zuotai
LI Cen, Zhan-dui, Leng-ben-cai-rang, Sang-lao, Suo-lang, Duo-jie-la-dan, Duo-ji, DU Yu-zhi, LI Lin-shuai, ZHANG Ming, YANG Hong-xia, BI Hong-tao, and WEI Li-xin
In order to reveal the chemical substance basis of pharmacodynamic effects of Zuotai,energy dispersive spectrometry of X-ray (EDX),X-ray fluorescence spectroscopy (XRF),synchrotron radiation X-ray absorption fine structure (SR-XAFS),X-ray diffraction (XRD),scanning electron microscope (SEM) and atomic force microscope In order to reveal the chemical substance basis of pharmacodynamic effects of Zuotai,energy dispersive spectrometry of X-ray (EDX),X-ray fluorescence spectroscopy (XRF),synchrotron radiation X-ray absorption fine structure (SR-XAFS),X-ray diffraction (XRD),scanning electron microscope (SEM) and atomic force microscope (AFM) were used to analyze the elements,the chemical valence and local structure of mercury,and the chemical phase composition and micro-morphology of Zuotai.EDX and XRF analysis shows that the main elements in Zuotai are Hg and S,with some other minor elements,such as O,Fe,Al,Cu,K,Ag,Ca,Mg etc.SR-XAFS analysis shows that:the oxidation state of mercury in Zuotai is divalence,its neighbor atoms are S,and its coordination number is four.XRD assay found that β-HgS (cubic,F-43m 216) and S8 (orthorhombic,Fddd 70) are the main phase compositions in Zuotai.Besides,it also has a small amount of C (hexagonal,P63/mmc 194),Fe1.05S0.95 (hexagonal,P63/mmc 194),Cu6S6 (hexagonal,P63/mmc 194),Cu1.8S (cubic,F-43m 216) and so on.And it was found that the crystallinity of Zuotai is about 59%,and the amorphous morphology substance in it is about 41%.SEM and AFM detection suggests that Zuotai is a kind of ancient micro-nano drug,and its particle size is mainly in the range of 100～600 nm,even less than 100 nm,which commonly further aggregate into several to 30 μm loose amorphous particles.In summary,the present study elucidated physicochemical characterization(elements composition,coordination information of mercury,phase composition and micro-morphology) of Zuotai,and it will play a positive role in promoting the interpretation of this mysterious drug..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1072 (2015)
Preparation and Performance of Ultrafast γ-CuI Scintillation Conversion Screen
XIA Ming, GU Mu, LIU Xiao-lin, LIU Bo, HUANG Shi-ming, and NI Chen
Micro-columnar structured γ-CuI scintillation conversion screen with columnar diameter in the micrometer and thickness about 17 μm were prepared by thermal evaporation method on quartz substrates with different temperatures.X-ray excited luminescence spectra of the screens show two peaks located at 430 nm and near 700 Micro-columnar structured γ-CuI scintillation conversion screen with columnar diameter in the micrometer and thickness about 17 μm were prepared by thermal evaporation method on quartz substrates with different temperatures.X-ray excited luminescence spectra of the screens show two peaks located at 430 nm and near 700 nm,which correspond to the fast and slow emission components,respectively.The fast one dominated.The intensity of 430 nm peak decreased as the substrate temperature rose from 170 ℃ to 210 ℃.At the same time the intensity of 700 nm band increased.The changes may be attributed to the iodine loss from screen caused by the substrate temperature.The phenomenon of iodine loss was observed by the Rutherford backscattering experiment.The crystal structure of the screens presents (111) preferred orientation,which is independent of the substrate temperature.As the temperature rose to 210 ℃,two weak additional peaks of (220) and (420) γ-CuI crystal planes in X-ray diffraction patterns appeared due to the increase in kinetic energy of CuI molecules.The scanning electron microscopy images of the screens showed that the columnar structure was improved when the substrate temperature increased from 170 ℃ to 190 ℃,but it would be degenerated when the temperature continued to rise to 210 ℃ because of the surface and bulk diffusion effects of the depositing molecules.Finally,the spatial resolution of the γ-CuI scintillation screens was measured by knife-edge method,and they are 4.5,7.2 and 5.6 lp·mm-1 for the screens prepared at the substrates temperatures of 170,190 and 210 ℃,respectively.The result shows that micro-column structure could improve the spatial resolution of γ-CuI scintillation screen..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1079 (2015)
The Influence of Oxygen Incorporation on the Microstructure and Band Gap Properties of the nc-Si Films
JIANG Zhao-yi, YU Wei, LIU Jian-ping, LIU Hai-xu, YIN Chen-chen, and DING Wen-ge
The authors prepared nc-SiOx:H thin films using plasma enhanced chemical vapor deposition methods (PECVD) and investigated the influence of oxygen incorporation on the microstructure and band gap properties of the films.The results indicated that with the increase in oxygen mixing ratio (CO2/SiH4),the grain size of theThe authors prepared nc-SiOx:H thin films using plasma enhanced chemical vapor deposition methods (PECVD) and investigated the influence of oxygen incorporation on the microstructure and band gap properties of the films.The results indicated that with the increase in oxygen mixing ratio (CO2/SiH4),the grain size of the nanocrystal-silicon grain as well as the crystallinity of the film reduced,and the surface tensile stress of the nanocrystal-silicon grain first increased and then decreased.Fourier infrared absorption spectra analysis indicated that,with the increase in oxygen mixing ratio,the intensity of the oxygen rich Si—O bond increased while that of the silicon rich Si—O bond decreased and the structure factor reduced in the meantime accompanied by the improved order degree of thin films.The structure factor increased when the oxygen mixing ratio exceeded 0.08,which shows that the order degree of thin films dropped.In addition,the optical gap increased and the band tail width first increased and then decreased as a result of the incorporation of the oxygen.As a result,the microstructure and band gap properties of the films can be controlled by incorporating oxygen.And the crystallinity and optical gap of the material was high,and the microstructure of the films was improved at the same time when the oxygen mixing ratio was 0.08,so it can be used as intrinsic layer of the thin-film solar cells..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1084 (2015)
Study on the Interface Characteristics of Cemented Carbide after Stripping Ti Department Coatings
YAN Qiang, LIANG Zheng, SONG Hui-jin, WU Tao, and WU Jun
TiAlN Coatings were stripped by chemical method,which were deposited on YW2 Alloy by arc ion plating.The surface morphology and composition of the cemented carbide after stripping TiAlN coatings by chemistry method were analyzed.It was found that TiAlN coatings on the cemented carbide substrates could be removed by beiTiAlN Coatings were stripped by chemical method,which were deposited on YW2 Alloy by arc ion plating.The surface morphology and composition of the cemented carbide after stripping TiAlN coatings by chemistry method were analyzed.It was found that TiAlN coatings on the cemented carbide substrates could be removed by being taken in 30% of hydrogen peroxide and potassium oxalate in alkaline mixed solution(VNaOH solution:V30%H2O2:VCOOK solution=1:1:1)at 45 ℃ for 45 minutes.The surface of the cemented carbide substrate was bright,and the color was the same as that before depositing TiAlN coatings.The surface of the substrate after removing was studied by X-ray photoelectron spectrum (XPS).The results showed that binding energies of the W element and the main peak of N element on the substrate surface were much close to the criterion binding energy in the XPS data-base;and the valence of the element on the YW2 alloy changed little.The Al,Ti and N elements diffusing into the superficial zone of the sample during the coating depositing process made their contents increase and the band energy location offset after stripping the coating.TiN and AlN were formed,which benefit to increase the film-substrate cohesion during re-preparing coatings.The influence of stripping solution on the corrosion degree of cemented carbide substrate was small..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1089 (2015)
Effect of Heat Treatment Temperature on the Spectral Properties of Cu-Ni Coating
LIU Xiao-zhen, SHEN Qin-wei, LIU Xiao-zhou, CHEN Jie, ZHU Liang-wei, and QI Jie
Cu-Ni coatings were prepared on the surface of nickel by electrodeposition method,and Cu-Ni coatings were heat-treated in 25 ~ 900 ℃.Heat-treated Cu-Ni coatings were characterized with scanning electron microscopy (SEM),energy dispersive x-ray analysis (EDAX) and X-ray diffraction (XRD) techniques,respectively.Effects Cu-Ni coatings were prepared on the surface of nickel by electrodeposition method,and Cu-Ni coatings were heat-treated in 25 ~ 900 ℃.Heat-treated Cu-Ni coatings were characterized with scanning electron microscopy (SEM),energy dispersive x-ray analysis (EDAX) and X-ray diffraction (XRD) techniques,respectively.Effects of heat treatment temperature on the spectral properties of Cu-Ni coatings were studied.The surface of Cu-Ni coating is composed of the nodules.The nodules of Cu-Ni coating surface become smaller with the increase in heat treatment temperature in 25 ~ 600 ℃.The nodules of Cu-Ni coating surface become smaller and the dividing line between the nodules becomes more blurred with the increase in heat treatment temperature in 600 ~ 900 ℃.The contents of copper in Cu-Ni coating decrease from 82.52 at% to 78.30 at% with the increase in heat treatment temperature in the range of 25 ~ 900 ℃;the contents of nickel in Cu-Ni coating increase from 17.48 at% to 21.70 at% with the increase in heat treatment temperature in the range of 25 ~ 900 ℃.The crystal structure of Cu-Ni coating is Cu0.81Ni0.19 cubic crystal structure.The crystal structure of the Cu0.81Ni0.19 becomes more complete with the increase in heat treatment temperature in 25 ~ 300 ℃.Part of crystal structure of the Cu0.81Ni0.19 can turn Cu0.81Ni0.19 cubic crystal structure into Cu3.8Ni cubic crystal structure,and is advantageous to Cu3.8Ni (311) and Cu0.81Ni0.19 (311) growth with the increase in heat treatment temperature in 600 ~ 900 ℃..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1094 (2015)
Correction of Fiber Throughput Variation Due to the Focal Ratio Degradation
CHEN Jian-jun, BAI Zhong-rui, LI Guang-wei, WANG Shu-qing, LUO A-li, and ZHAO Yong-heng
The focal ratio degradation (FRD) of optical fiber is one of major sources causing light loss in multi-fiber astronomical instruments.Meanwhile,the sky subtraction is crucial to multi-fiber spectra reduction,especially for the objects which are as faint as the sky background,not to mention for those even fainter ones.TThe focal ratio degradation (FRD) of optical fiber is one of major sources causing light loss in multi-fiber astronomical instruments.Meanwhile,the sky subtraction is crucial to multi-fiber spectra reduction,especially for the objects which are as faint as the sky background,not to mention for those even fainter ones.To improve the accuracy of sky subtraction,it is necessary to normalize the throughput among object fibers and sky sampling fibers.The rotation and twist during mounting and rotating could change the FRD of individual fibers,which means the variation of the transmission throughput among fibers.We investigate such throughput variation among LAMOST fibers and its correlation with the intensity of sky emission lines on all wavelength coverage in this paper.On the basis of this work,we present an approach to correcting the varied fiber throughput by measuring the intensity of the sky emission lines as the secondary throughput correction.This approach has been applied to LAMOST 2D Pipeline..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1099 (2015)
Spectra Classification Based on Local Mean-Based K-Nearest Centroid Neighbor Method
TU Liang-ping, WEI Hui-ming, WANG Zhi-heng, WEI Peng, LUO A-li, and ZHAO Yong-heng
In the present paper,a local mean-based K-nearest centroid neighbor (LMKNCN) technique is used for the classification of stars,galaxies and quasars(QSOS).The main idea of LMKNCN is that it depends on the principle of the nearest centroid neighborhood(NCN),and selects K centroid neighbors of each class as training samplIn the present paper,a local mean-based K-nearest centroid neighbor (LMKNCN) technique is used for the classification of stars,galaxies and quasars(QSOS).The main idea of LMKNCN is that it depends on the principle of the nearest centroid neighborhood(NCN),and selects K centroid neighbors of each class as training samples and then classifies a query pattern into the class with the distance of the local centroid mean vector to the samples .In this paper,KNN,KNCN and LMKNCN were experimentally compared with these three different kinds of spectra data which are from the United States SDSS-DR8.Among these three methods,the rate of correct classification of the LMKNCN algorithm is higher than the other two algorithms or comparable and the average rate of correct classification is higher than the other two algorithms,especially for the identification of quasars.Experiment shows that the results in this work have important significance for studying galaxies,stars and quasars spectra classification..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1103 (2015)
Instrumentation and Application of a Portable Pretreating System for a Speedy Plasmon-Enhanced Raman Spectroscopy Detection Towards Food Safety
NI Wei-quan, HE Jian, LIU Guo-kun, CHEN Hong-ju, ZENG Yong-ming, and TIAN Zhong-qun
The present paper developed a portable and fast sample pretreatment apparatus.It has many virtues like being portable,low power consumption and convenient operation,short extraction time and sound repeatability.Therefore,it can meet the requirements of on-site rapid detection pretreatment.The apparatus consists of fourThe present paper developed a portable and fast sample pretreatment apparatus.It has many virtues like being portable,low power consumption and convenient operation,short extraction time and sound repeatability.Therefore,it can meet the requirements of on-site rapid detection pretreatment.The apparatus consists of four functional modules:ultrasonic extraction unit,heating unit,exhaust gas evaporation and absorption unit and control system.In addition,LED control panel and alarm device were designed.The whole treatment process needs three steps:ultrasonic extraction,liquid-liquid extraction and solvent evaporation by heating and pumping.For test of this apparatus performance,three real samples (pepper powder,pepper oil,bean sauce) containing banned additive Rhodamine B were taken as experiment objects.Compared with conventional laboratory pretreatment method,the PERS spectra achieved by two methods were little changed,but the experiment time was halved.In addition,the test results showed relative standard deviation less than ±5%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1107 (2015)
Establishment and Improvement of Portable X-Ray Fluorescence Spectrometer Detection Model Based on Wavelet Transform
LI Fang, WANG Ji-hua, LU An-xiang, and HAN Ping
The concentration of Cr,Cu,Zn,As and Pb in soil was tested by portable X-ray fluorescence spectrometer.Each sample was tested for 3 times,then after using wavelet threshold noise filtering method for denoising and smoothing the spectra,a standard curve for each heavy metal was established according to the standard valuThe concentration of Cr,Cu,Zn,As and Pb in soil was tested by portable X-ray fluorescence spectrometer.Each sample was tested for 3 times,then after using wavelet threshold noise filtering method for denoising and smoothing the spectra,a standard curve for each heavy metal was established according to the standard values of heavy metals in soil and the corresponding counts which was the average of the 3 processed spectra.The signal to noise ratio (SNR),mean square error (MSE) and information entropy (H) were taken to assess the effects of denoising when using wavelet threshold noise filtering method for determining the best wavelet basis and wavelet decomposition level.Some samples with different concentrations and H3BO3 (blank) were chosen to retest this instrument to verify its stability.The results show that:the best denoising result was obtained with the coif3 wavelet basis at the decomposition level of 3 when using the wavelet transform method.The determination coefficient (R2) range of the instrument is 0.990~0.996,indicating that a high degree of linearity was found between the contents of heavy metals in soil and each X-ray fluorescence spectral characteristic peak intensity with the instrument measurement within the range(0~1 500 mg·kg-1).After retesting and calculating,the results indicate that all the detection limits of the instrument are below the soil standards at national level.The accuracy of the model has been effectively improved,and the instrument also shows good precision with the practical application of wavelet transform to the establishment and improvement of X-ray fluorescence spectrometer detection model.Thus the instrument can be applied in on-site rapid screening of heavy metal in contaminated soil..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1111 (2015)
Study on the Spectral Characteristics of the Narrow-Band Filter in SHS
LUO Hai-yan, SHI Hai-liang, LI Zhi-wei, LI Shuang, XIONG Wei, and HONG Jin
The spectral response of spatial heterodyne spectroscopy (SHS) is determined by the spectrum property of narrow-band filter.As discussed in previous studies,the symmetric heterodyned interferogram of high frequency waves modulated by SHS and lack of sample lead to spectral confusion,which is associated with the true anThe spectral response of spatial heterodyne spectroscopy (SHS) is determined by the spectrum property of narrow-band filter.As discussed in previous studies,the symmetric heterodyned interferogram of high frequency waves modulated by SHS and lack of sample lead to spectral confusion,which is associated with the true and ghost spectra.Because of the deviation from theoretical index of narrow-band filter in the process of coating,the boarded spectral response and middle wave shift are presented,and conditions in the theoretical Littrow wavelength made the effective wavelength range of SHS reduced.According to the measured curve of filter,a new wavenumber of zero spatial frequency can be reset by tunable laser,and it is easy for SHS to improve the spectral aliasing distortion.The results show that it is utilized to the maximum extent of the effective bandwidth by adjusting the grating angle of rotation to change the Littrow wavelength of the basic frequency,and the spectral region increased to 14.9 nm from original 12.9 nm..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1116 (2015)
A Method for Selecting Self-Adoptive Chromaticity of the Projected Markers
ZHAO Shou-bo, ZHANG Fu-min, QU Xing-hua, ZHENG Shi-wei, and CHEN Zhe
The authors designed a self-adaptive projection system which is composed of color camera,projector and PC.In detail,digital micro-mirror device (DMD) as a spatial light modulator for the projector was introduced in the optical path to modulate the illuminant spectrum based on red,green and blue light emitting diodes (LThe authors designed a self-adaptive projection system which is composed of color camera,projector and PC.In detail,digital micro-mirror device (DMD) as a spatial light modulator for the projector was introduced in the optical path to modulate the illuminant spectrum based on red,green and blue light emitting diodes (LED).However,the color visibility of active markers is affected by the screen which has unknown reflective spectrum as well.Here active markers are projected spot array.And chromaticity feature of markers is sometimes submerged in similar spectral screen.In order to enhance the color visibility of active markers relative to screen,a method for selecting self-adaptive chromaticity of the projected markers in 3D scanning metrology is described.Color camera with 3 channels limits the accuracy of device characterization.For achieving interconversion of device-independent color space and device-dependent color space,high-dimensional linear model of reflective spectrum was built.Prior training samples provide additional constraints to yield high-dimensional linear model with more than three degrees of freedom.Meanwhile,spectral power distribution of ambient light was estimated.Subsequently,markers’ chromaticity in CIE color spaces was selected via maximization principle of Euclidean distance.The setting values of RGB were easily estimated via inverse transform.Finally,we implemented a typical experiment to show the performance of the proposed approach.An 24 Munsell Color Checker was used as projective screen.Color difference in the chromaticity coordinates between the active marker and the color patch was utilized to evaluate the color visibility of active markers relative to the screen.The result comparison between self-adaptive projection system and traditional diode-laser light projector was listed and discussed to highlight advantage of our proposed method..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1120 (2015)
Analysis of SPR Signal by Using Optimized Savitzky-Golay Filter
CHEN Shu-wang, WANG Jun-xing, SHENG Wei-nan, LIU Jin, ZHANG Wen-bin, and ZHOU Peng
The spectrum of surface plasmon resonance shows different amplitudes and peak widths with the effects of resonant intensity and position,so it’s necessary to develop the self-adaptive methods to guarantee the accurate positioning of SPR formant.Based on the optimized Savitzky-Golay filter,this paper presents a method fThe spectrum of surface plasmon resonance shows different amplitudes and peak widths with the effects of resonant intensity and position,so it’s necessary to develop the self-adaptive methods to guarantee the accurate positioning of SPR formant.Based on the optimized Savitzky-Golay filter,this paper presents a method for SPR spectrum,which can optimize the parameters (polynomial degree and window size) according to the characteristics of the real time SPR spectrum,and minimizes the Stein’s unbiased risk estimate of the mean squared error,and it can be quickly solved by Monte-Carlo methods.It is confirmed that SURE can accurately reflect the trends and the results of the true MSE.The experiment measures the SPR signals of sucrose under different concentrations and integration time through the SPR system.By using the proposed method of optimal parameters on the SPR signal filtering,the results show that the repeatability error of the position of SPR formant is smaller compared with the fixed parameters,and does not increase with the addition of noise levels..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1124 (2015)
Research on Spectral Polarization Imaging System Based on Static Modulation
ZHAO Hai-bo, LI Huan, LIN Xu-ling, and WANG Zheng
The main disadvantages of traditional spectral polarization imaging system are:complex structure,with moving parts,low throughput.A novel method of spectral polarization imaging system is discussed,which is based on static polarization intensity modulation combined with Savart polariscope interference imaging.The imagiThe main disadvantages of traditional spectral polarization imaging system are:complex structure,with moving parts,low throughput.A novel method of spectral polarization imaging system is discussed,which is based on static polarization intensity modulation combined with Savart polariscope interference imaging.The imaging system can obtain real-time information of spectral and four Stokes polarization messages.Compared with the conventional methods,the advantages of the imaging system are compactness,low mass and no moving parts,no electrical control,no slit and big throughput.The system structure and the basic theory are introduced.The experimental system is established in the laboratory.The experimental system consists of re-imaging optics,polarization intensity module,interference imaging module,and CCD data collecting and processing module.The spectral range is visible and near-infrared (480～950 nm).The white board and the plane toy are imaged by using the experimental system.The ability of obtaining spectral polarization imaging information is verified.The calibration system of static polarization modulation is set up.The statistical error of polarization degree detection is less than 5%.The validity and feasibility of the basic principle is proved by the experimental result.The spectral polarization data captured by the system can be applied to object identification,object classification and remote sensing detection..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1129 (2015)
AOTF-Based Imaging Spectrometer and Its Applications in the Identification of Metameric Targets
LIU Kang, GAO Zhi-fan, WU Qiong-shui, and ZENG Li-bo
For obtaining spectrum information and space distribution information of metameric targets at the same time,an AOTF-based imaging spectrometer was developed,which consists of a front imaging lens assembly,an AOTF filter imaging module,an AOTF driver,a plane array CCD,an image acquisition card and a PC.Under the controlFor obtaining spectrum information and space distribution information of metameric targets at the same time,an AOTF-based imaging spectrometer was developed,which consists of a front imaging lens assembly,an AOTF filter imaging module,an AOTF driver,a plane array CCD,an image acquisition card and a PC.Under the control of the PC,a spectral image cube can be obtained by a fast wavelength scanning process,thereby the spectrum information of any point on the image is available.The developed imaging spectrometer,with a spectral range from 550~1 000 nm and a spectral resolution of 2.6 nm(@632 nm),and a less than 80 s switch time between any two wavelengths,has the characteristics of no mechanical moving part,low power dissipation and strong vibration resistance.The identification test of true and false roses and the information recovery experiment of altered physical evidence were carried out,The true and false roses were identified and the altered physical evidence was recovered,The experimental results showed that the imaging spectrometer has an excellent ability of identifying metameric targets,indicating a good application prospect..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1134 (2015)
Monitoring of Curing Temperature of Pouring Explosive Based on Fiber Bragg Grating
ZHANG Chen, WANG Gao, LIANG Hai-jian, YUAN Jun-ming, CHANG Shuang-jun, LIU Yu-cun, WANG Heng-fei, and ZHAO Yu
For the first time,we real time measured released reaction heat between the binder and the curing agent in the curing process of cast explosive using fiber Bragg grating.In order to obtain the temperature in the process of pouring explosive casting real time and accurately,we designed the temperature monitoring system For the first time,we real time measured released reaction heat between the binder and the curing agent in the curing process of cast explosive using fiber Bragg grating.In order to obtain the temperature in the process of pouring explosive casting real time and accurately,we designed the temperature monitoring system based on fiber Bragg grating.Given the risk of explosive component,long curing time and the requirements of constant temperature,a suitable measurement method for direct real-time monitoring has not been found.In recent years,due to its superior characteristics,fiber Bragg grating is widely used in the field of communication and sensing.We will make the collected reflection wavelength to convert real-time temperature displaying,utilizing linear relationship between fiber Bragg grating and temperature.Through WDM technology,seven grating points are written in two optical fibers to measure at the same time,and distribution trend of explosives internal temperature can be displayed in real time by multi-point distributed measurement.The curved design of the sensor not only improves the connection between sensor and jumper,but also benefits to place in oven.The txt data is made to draw a graph using origin software,and the changes in temperature in the curing process are displayed intuitively.The results show that this method is simple and high-precision,and meets the testing requirements of curing temperature of explosives..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1138 (2015)
Study of Spectral Property and Measurement of Linear Variable Filters
LIU Qing, ZHOU Jin-song, NIE Yun-feng, LI Yang, and ZHANG Gui-feng
Linear variable filters(LVF) are widely used in a variety of small rapid spectrometric detecting devices.In the present paper,the splitting property of LVF was studied,and the spectral-property expression in Gaussian form was given,and the relationship between indexes of expression and LVF center transmission,width of Linear variable filters(LVF) are widely used in a variety of small rapid spectrometric detecting devices.In the present paper,the splitting property of LVF was studied,and the spectral-property expression in Gaussian form was given,and the relationship between indexes of expression and LVF center transmission,width of spectrum,and linear dispersion was specified.Measurement based on monochromator for imaging spectrometers calibration was introduced,the sensitivity for detection system was discussed,and the tolerance was analyzed.It was shown that the slit displacement of monochromator relative to the optical axle and the slope of LVF affect the detecting accuracy most,and the tolerance can be reduced by adjustment of optical path and structure to reach requirement.System was built and the detection for spectral property of sample LVF was made.The result of data processing indicates that MSE for center transmission detection was lower than 0.05%,and the accuracy of this method was proved.Reference-parameters of relevant system designing and calibrating based on the LVF can be provided by this method..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1142 (2015)
Adaptive “3R” De-Noising Algorithm Based on Near Infrared Bi-Spectrum
ZHAO Xiao-yu, FANG Yi-ming, TAN Feng, WANG Zhi-gang, and TONG Liang
Adaptive de-noising algorithm is proposed based on transmission spectrum and absorption spectrum of near infrared.Near infrared transmission spectrum and absorption spectrum collected synchronously are decomposed into intrinsic mode functions by ensemble empirical mode decomposition;the intrinsic mode function is a sinAdaptive de-noising algorithm is proposed based on transmission spectrum and absorption spectrum of near infrared.Near infrared transmission spectrum and absorption spectrum collected synchronously are decomposed into intrinsic mode functions by ensemble empirical mode decomposition;the intrinsic mode function is a single frequency component.Correlations between intrinsic mode functions and transmission spectrum,absorption spectrum were calculated,and the correlation between intrinsic mode functions of transmission spectrum and absorption spectrum was also computed.The results show that the intrinsic mode function with minimum correlation coefficient should be noise component.The self-correlation of this intrinsic mode function was analyzed to judge whether the intrinsic mode function is noise.IF the self-correlation is very large at the midpoint and is zero or very small at the other point of the spectrum,then the intrinsic mode function is noise component for judgment,based on which “3R” algorithm is named to judge whether the intrinsic mode function is noise component.Removing noise component,constructing spectral signal and circulating the previous decomposition was conducted,and the noise reduction process was ended until it did not meet the “3R” rule.To do experiment on the simulated spectrum with noise,the effect of de-noising with “3R” algorithm is better than EMD and EEMD low pass filter,and it is not so good as wavelet decomposition.In the real spectrum testing,the model was established between spectra treated by above methods with chlorophyll on three layers.BP neural network,and the model de-noised by “3R” method has the biggest correlation coefficient and prediction coefficient,but the smallest correction standard error and prediction standard error.“3R” method’s effects on the peak position and peak intensity of spectrum are the smallest among the four kinds of de-noising methods.Experiments show that the “3R” algorithm based on bi-spectrum can be used for near infrared spectra de-nosing without presetting the number of iterations,there is no need to consider layers of decomposition,also no need of basis function,and the adaptability is very strong..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 4, 1146 (2015)
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