Journals >Spectroscopy and Spectral Analysis
Contents
2011
Volume: 31 Issue 7
62 Article(s)
Export citation format
Research Article
Study on the Movement of the Carrier Recombination Region in Organic Light-Emitting Diodes (OLEDs) Based on DPVBi/Alq3
YAN Guang, ZHAO Su-ling, XU Zheng, ZHANG Fu-jun, KONG Chao, LIU Xiao-dong, GONG Wei, and GAO Li-yan
Series of organic light emitting devices with basic structure of ITO/PCBM: PVK(x Wt%, ~40 nm)/DPVBi(30 nm)/Alq3(30 nm)/Al were fabricated in order to investigate the carrier recombination region movement in these devices. The carrier injection-dependent, the carrier transport-dependent and the voltage-dependent carrierSeries of organic light emitting devices with basic structure of ITO/PCBM: PVK(x Wt%, ~40 nm)/DPVBi(30 nm)/Alq3(30 nm)/Al were fabricated in order to investigate the carrier recombination region movement in these devices. The carrier injection-dependent, the carrier transport-dependent and the voltage-dependent carrier recombination region movements were investigated respectively by modifying cathode with lithium fluoride, by changing the doping concentration of PCBM and by changing the voltage on the devices. The physical mechanism behind the voltage-dependent carrier recombination region movement was discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1729 (2011)
Synthesis, Crystal Structure and Luminescent Properties of a Dysprosium CoordinaAtion Polymer Based on Pyridine-2,6-Dicarboxylic Acid
FAN Rui-qing, WANG Ping, REN Jin-yu, ZHOU Guang-peng, and YANG Yu-lin
2-D layered Dy coordination polymer ［Dy(PDA)(HPDA)］n (1)(H2PDA=pyridine-2,6-dicarboxylic acid) with (4.82) topological network was synthesized under hydrothermal conditions and was characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. X-ray diffraction analysis reveals that compound 1 2-D layered Dy coordination polymer ［Dy(PDA)(HPDA)］n (1)(H2PDA=pyridine-2,6-dicarboxylic acid) with (4.82) topological network was synthesized under hydrothermal conditions and was characterized by elemental analysis, IR spectrum, and single-crystal X-ray diffraction. X-ray diffraction analysis reveals that compound 1 is monoclinic, space group P2(1)/c. In the structure of compound 1, metal-centered Dy is connected via O atoms of H2PDA ligands to form a (4.82) topology network. The 3-D supramolecular structure of 1 is constructed through π—π stacking interactions between the adjacent layers. The luminescence properties of 1 were determined by UV-Vis and fluorescence spectrum in solid state at room temperature. The H2PDA and 1 exhibit the similar broad maximum absorption peak at 280 nm, which are attributed to ligand-centered π—π* transition. The fluorescence emission band based on ligand-center and characteristic emission of Dy3+ at the same maximum excitation wavelength of 280 nm were observed in 1. The fluorescence decay curve of complex 1 indicated that the processes of decay consists of two components, of which corresponding lifetimes τ1=3.61 μs and τ2=12.81 μs..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1734 (2011)
Research on the Photoelectric Conversion Efficiency of Grating Antireflective Layer Solar Cells
ZHONG Hui, GAO Yong-yi, ZHOU Ren-long, ZHOU Bing-ju, TANG Li-qiang, WU Ling-xi, and LI Hong-jian
A numerical investigation of the effect of grating antireflective layer structure on the photoelectric conversion efficiency of solar cells was carried out by the finite-difference time-domain method. The influence of grating shape, height and the metal film thickness coated on grating surface on energy storage was anaA numerical investigation of the effect of grating antireflective layer structure on the photoelectric conversion efficiency of solar cells was carried out by the finite-difference time-domain method. The influence of grating shape, height and the metal film thickness coated on grating surface on energy storage was analyzed in detail. It was found that the comparison between unoptimized and optimized surface grating structure on solar cells shows that the optimization of surface by grating significantly increases the energy storage capability and greatly improves the efficiency, especially of the photoelectric conversion efficiency and energy storage of the triangle grating. As the film thickness increases, energy storage effect increases, while as the film thickness is too thick, energy storage effect becomes lower and lower..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1739 (2011)
Luminescence of Sr2Mg(BO3)2∶Tb3+ under Vacuum Ultraviolet Excitation
LIN Hui-hong, LIANG Hong-bin, SU Qiang, and ZHANG Guo-bin
The phosphors of Tb3+ activated Sr2Mg(BO3)2 were prepared by high temperature solid-state reaction technique. The phase purity was characterized by the powder X-ray diffraction (XRD). The luminescence properties in VUV-Vis range as well as the decay curves were investigated. The results demonstrate that the band near 1The phosphors of Tb3+ activated Sr2Mg(BO3)2 were prepared by high temperature solid-state reaction technique. The phase purity was characterized by the powder X-ray diffraction (XRD). The luminescence properties in VUV-Vis range as well as the decay curves were investigated. The results demonstrate that the band near 178 nm in the VUV excitation spectra is ascribed to the host-related absorption. The bands of lowest spin-allowed and spin-forbidden f—d transition are located at 235 and 278 nm, respectively. The strongest emission is at 543 nm upon 172 nm excitation and with the color coordinate (0.30, 0.45). The decay time is about 2.8 ms..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1743 (2011)
TG-FTIR Analysis of Thermal Degradation of Bischofite’s Crystals with Aniline Hydrochloride
NI Qian-yin, WU Yu-long, YANG Ming-de, HU Hu-sheng, HE Yong-feng, ZHANG Li-jia, and DANG Jie
The dehydration of bischofite is the key to the use of magnesium resource. Double salts or complex method is an important way to prepare anhydrous magnesium chloride. The crystals of bischofite and aniline hydrochloride were prepared through lowering the temperature of the mixture’s aquatic solution slowly. The pyrolysThe dehydration of bischofite is the key to the use of magnesium resource. Double salts or complex method is an important way to prepare anhydrous magnesium chloride. The crystals of bischofite and aniline hydrochloride were prepared through lowering the temperature of the mixture’s aquatic solution slowly. The pyrolysis of aniline hydrochloride, bischofite and the crystals was qualitatively analyzed by TG-FTIR under 400 ℃. We infered the reaction process through qualitative detection of escaping gas of each decomposition step. The Experimental results showed that there were three steps in the thermal decomposition of bischofite. In the first step, nearly four crystallized waters decomposed, while hydrolysis and decomposition took place together in the next two steps, but hydrolysis was the main reaction at the lower temperature (205～235 ℃), and comparative decomposition was the main one at the higher temperature (235～287 ℃). In the experimental temperature range, aniline hydrochloride didn’t decompose. Water and aniline hydrochloride left the crystals at different temperature, and no hydrolysis reaction occurred. Anhydrous magnesium chloride can be prepared though this way..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1747 (2011)
In Situ FTIR and XPS Study on Selective Hydrodesulfurization Catalyst of FCC Gasoline
Qiherima, YUAN Hui, ZHANG Yun-hong, LI Hui-feng, and XU Guang-tong
Improvement of the selectivity of hydrodesulfurization (HDS) for hydrogenation (HYD) of olefins is crucial to produce sulfur-free (S＜0.001%) gasoline from fluid catalytic-cracked (FCC) gasoline. A series of sulfided CoMo/Al2O3 catalysts with different metal loading were prepared by pore-filling impregnation. MoS2 and CImprovement of the selectivity of hydrodesulfurization (HDS) for hydrogenation (HYD) of olefins is crucial to produce sulfur-free (S＜0.001%) gasoline from fluid catalytic-cracked (FCC) gasoline. A series of sulfided CoMo/Al2O3 catalysts with different metal loading were prepared by pore-filling impregnation. MoS2 and CoMoS active phases on the surface of sulfided CoMo/Al2O3 catalyst were identified and analyzed quantitatively by XPS and in-situ FTIR of adsorbed CO. The results reveal that the increase in CoMoS phase on the catalyst surface improves the HDS activity and selectivity. And the HDS selectivity correlates linearly with the ratio of active site number of CoMoS and MoS2, the higher the ratio of active site number of CoMoS and MoS2, the better the HDS selectivity. In situ variable temperature FTIR analysis shows that CoMoS phase has stronger electron accepting ability than MoS2. The strong electron deficient property of CoMoS active sites is the main reason for its excellent HDS activity and selectivity..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1752 (2011)
Genetic Programming Used for the Measurement of CO Concentration Based on Nondispersive Infrared Absorption Spectroscopy
CHEN Jin, DUAN Fa-jie, TONG Ying, and GAO Qiang
Nondispersive infrared absorption spectroscopy(NDIR) is an important method to measure CO concentration in the air. In the present study, an open-path measurement system and continuous measuring device was developed, and genetic programming was used to establish the calibration model of subjects’ light intensity sampliNondispersive infrared absorption spectroscopy(NDIR) is an important method to measure CO concentration in the air. In the present study, an open-path measurement system and continuous measuring device was developed, and genetic programming was used to establish the calibration model of subjects’ light intensity sampling values. Continuous measurements were carried out in 10 different concentration of CO, and 40 sampled data were acquired and analyzed. For validation set, the correlation coefficient was 0.999 7. The biggest relative error of validation was 4.00%, and the average relative error was 1.11%. Results show that genetic programming can be a good method for the modeling of gas concentration measurements equipped with NDIR systems..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1758 (2011)
High Precision All-Reflection Fourier Transform Imaging Spectrometer Spectral Calibration Using Homogeneous Broadening of the Wave Number Model
CUI De-qi, LIAO Ning-fang, CAO Wei-liang, TAN Bo-neng, and TIAN Li-xun
All-reflection Fourier transform imaging spectrometer (ARFTIS) is a novel imaging spectrometer. The specialty is not only high spectrum resolution, but also wide band and non-chromatism. It is good for remote sensing field of wide band imaging. Single spectrum calibration, average calibration and weighted average calibAll-reflection Fourier transform imaging spectrometer (ARFTIS) is a novel imaging spectrometer. The specialty is not only high spectrum resolution, but also wide band and non-chromatism. It is good for remote sensing field of wide band imaging. Single spectrum calibration, average calibration and weighted average calibration are three common calibration methods. However, they all are limited. Because they cannot meet the demand on both convenience and high precision. In the present paper, the authors propose a novel model for spectrum calibration. It can work in high precision with single spectrum calibration. At the same time, the method is steady, and the average error is less than 5% with multi-bands calibration. It provides a convenient way for the non-professional calibration situation and outer simply calibration work..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1762 (2011)
Using Barium Fluoride Fine Particles as Stationary Phase for TLC/FTIR Analysis
LIU Xi, PAN Qing-hua, DING Jie, ZHU Qing, HE An-qi, YUE Shi-juan, LI Xiao-pei, HU Li-ping, XIA Jin-ming, LIU Cui-ge, WEI Yong-ju, YU Jiang, YANG Zhan-lan, ZHU Xi, XU Yi-zhuang, and WU Jin-guang
In situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase such as silica gel etc. has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of sIn situ TLC/FTIR technique has tremendous potential in the analysis of complex mixtures. However, the progress in this technique was quite slow. The reason is that conventional stationary phase such as silica gel etc. has strong absorption in FTIR spectrum and thus brings about severe interference in the detection of samples. To solve the problem, the authors propose to use barium fluoride fine particles as stationary phase of TLC plate. The reasons are as follows: Barium fluoride wafer has been extensively used as infrared window in FTIR experiments and it has no absorbance in an IR region between 4 000 and 800 cm-1. As a matter of fact, the atomic mass of barium and fluoride is quite large, thus the normal vibration of BaF2 lattice is limited in far-IR region and low frequency part of mid-IR region. Therefore, the interference caused by IR absorption of stationary phase can be resolved if BaF2 is used as stationary phase of TLC plate. Moreover, BaF2 is quite stable and insolvable in water and most organic solvents and it will not be dissolved by mobile phase or react with samples in TLC separation. Additionally, decreasing the particle size of BaF2 is very important in TLC/FTIR analysis technique. The reason is two-fold: First, decreasing the particle size of stationary phase is helpful to improving the efficiency of separation by TLC plate; second, decreasing the size of BaF2 particle can improve the quality of FTIR spectra by alleviating the problem of light scattering. By optimizing the synthetic conditions, fine particles of barium fluoride were obtained. SEM results indicate that the size of the BaF2 particles is around 500 nm. FTIR spectrum of the BaF2 particles shows that no absorption of impurity was observed. Moreover, the elevation of baseline caused by light scattering is insignificant. The authors have developed a new technique named “settlement volatilization method” to prepare TLC plate without polymeric adhesive that may bring about significant interference in FTIR analysis. Preliminary TLC experiments proved that the TLC plate using BaF2 fine particles as stationary phase can separate rhodamine B from methylene blue successfully. Applications of barium fluoride fine particles as stationary phase have bright perspective in the development of new in-situ TLC/FTIR analysis techniques..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1767 (2011)
Rapid Analysis of Added Ingredients in Heroin
WANG Ji-fen, YU Jing, GUO Xin, SUN Xing-long, and WANG Ding-fang
The method of rapid analysis of added ingredients in heroin was studied in the present paper. Adding sucrose, fructose, glucose, starch, caffeine and phenacetin to heroin with a certain percentage, the changes in the infrared spectrum with the concentration of heroin increasing and the detection limit of the additives The method of rapid analysis of added ingredients in heroin was studied in the present paper. Adding sucrose, fructose, glucose, starch, caffeine and phenacetin to heroin with a certain percentage, the changes in the infrared spectrum with the concentration of heroin increasing and the detection limit of the additives were determined. Whether or not heroin can be detected in the sample with high concentration of added ingredients was studied using Raman spectroscopy. Similarly, in high purity of heroin, whether or not Raman spectroscopy can detect the added ingredients was tested. Through systematic experiments, the results showed that: using infrared spectroscopy and Raman spectroscopy to test the added ingredients of heroin is a rapid and effective method. Each has both advantages and disadvantages. We should select the appropriate method according to the actual cases..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1772 (2011)
Application of DPLS-Based LDA in Corn Qualitative Near Infrared Spectroscopy Analysis
QIN Hong, WANG Hui-rong, LI Wei-jun, and JIN Xiao-xian
NIR technology is a rapid, nondestructive and user-friendly method ideally suited for Qualitative analysis. In this paper the authors present the use of discriminant partial least Squares (DPLS)-based linear discriminant analysis (LDA) in corn qualitative near infrared spectroscopy analysis. Firstly, a training set incNIR technology is a rapid, nondestructive and user-friendly method ideally suited for Qualitative analysis. In this paper the authors present the use of discriminant partial least Squares (DPLS)-based linear discriminant analysis (LDA) in corn qualitative near infrared spectroscopy analysis. Firstly, a training set including 30 corn varieties (each variety has 20 samples) was used to build the DPLS regression model, and 28 principal components (DPLS-PCs) were obtained from original spectrum. Secondly, the DPLS-PCs scores of the training set were extracted as DPLS features. Thirdly, LDA was applied to the DPLS features, determining 26 principal components (LDA-PCs). A test sample was first projected onto the DPLS-PCs and then onto the LDA-PCs, and finally 26 DPLS+LDA features were obtained. The recognition results were obtained by minimum distance classifier. DPLS+LDA method achieved 96.18% recognition rate, while traditional DPLS regression method and DPLS feature extraction method only achieved 85.38% and 95.76% recognition rate respectively. The experiment results indicated that DPLS+LDA method is with better generalization ability compared with traditional DPLS regression method and NIRS analysis by DPLS+LDA method is an efficient way to discriminate corn species..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1777 (2011)
Determination of Taste Quality of Green Tea Using FT-NIR Spectroscopy and Variable Selection Methods
WU Rui-mei, ZHAO Jie-wen, CHEN Quan-sheng, and HUANG Xing-yi
The present paper was attempted to study the feasibility to determine the taste quality of green tea using FT-NIR spectroscopy combined with variable selection methods. Chemistry evaluation, as the reference measurement, was used to measure the total taste scores of green tea infusion. First, synergy interval PLS (siPLThe present paper was attempted to study the feasibility to determine the taste quality of green tea using FT-NIR spectroscopy combined with variable selection methods. Chemistry evaluation, as the reference measurement, was used to measure the total taste scores of green tea infusion. First, synergy interval PLS (siPLS) was implemented to select efficient spectral regions from SNV preprocessed spectra; then, optimal variables were selected using genetic algorithm (GA) from these selected spectral regions by siPLS, and the optimal model was achieved with Rp=0.890 8, RMSEP=4.66 in the prediction set when 38 variables and 6 PLS factors were included. Experimental results showed that the performance of siPLS-GA model was superior to those of others. This study demonstrated that NIR spectra could be used successfully to measure taste quality of green tea and siPLS-GA algorithm has superiority to other algorithm in developing NIR spectral regression model..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1782 (2011)
FTIR Analysis of Protein Secondary Structure in Cheddar Cheese during Ripening
WANG Fang, LIU Ai-ping, REN Fa-zheng, ZHANG Xiao-ying, Stephanie Clark, ZHANG Lu-da, and GUO Hui-yuan
Proteolysis is one of the most important biochemical reactions during cheese ripening. Studies on the secondary structure of proteins during ripening would be helpful for characterizing protein changes for assessing cheese quality. Fourier transform infrared spectroscopy (FTIR), with self-deconvolution, second derivatiProteolysis is one of the most important biochemical reactions during cheese ripening. Studies on the secondary structure of proteins during ripening would be helpful for characterizing protein changes for assessing cheese quality. Fourier transform infrared spectroscopy (FTIR), with self-deconvolution, second derivative analysis and band curve-fitting, was used to characterize the secondary structure of proteins in Cheddar cheese during ripening. The spectra of the amide I region showed great similarity, while the relative contents of the secondary structures underwent a series of changes. As ripening progressed, the α-helix content decreased and the β-sheet content increased. This structural shift was attributed to the strengthening of hydrogen bonds that resulted from hydrolysis of caseins. In summary, FTIR could provide the basis for rapid characterization of cheese that is undergoing ripening..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1786 (2011)
Raman Spectrum Study of the Calcium Phosphate Glass Structure Affected by the Addition of TiO2
LIANG Xiao-feng, YIN Guang-fu, YANG Shi-yuan, and WANG Jun-xia
Calcium phosphate glasses in which part of CaO was replaced by TiO2 were prepared by the conventional melt quench method. The structures and their thermal properties were studied by XRD, Raman and DSC techniques. The results show that, TiO2 and calcium phosphate form homogeneous glass with the amount of the additive leCalcium phosphate glasses in which part of CaO was replaced by TiO2 were prepared by the conventional melt quench method. The structures and their thermal properties were studied by XRD, Raman and DSC techniques. The results show that, TiO2 and calcium phosphate form homogeneous glass with the amount of the additive less than 3 mol%. The glasses matrix generates a Ca2P2O7 and CaTi4(PO4)6 crystal phase with the amount of the additives in the range of 6~12 mol%. With the addition of TiO2, the structural changes of the glass system are from metaphosphate to pyrophosphate and orthophosphate. With the TiO2 less than 3 mol%, the cohesion of the glasses structure and the glasses thermal stability is enhanced, and the glasses transition temperature is gradually increased..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1790 (2011)
Raman Spectroscopic Quantitative Analysis of Cluster Structure of Binary Alkali Silicate Glasses
WANG Zhi-chao, YOU Jing-lin, WANG Yuan-yuan, NIU Yu-jing, and DAI Su-juan
A calibration method for Raman spectroscopic quantitative analysis of binary alkaline silicate glasses is proposed. By applying ab initio quantum chemistry simulation, Raman optical activities (ROA) of various cluster units consisting of silicon-oxygen tetrahedra (SiOT) with different number of non-bridging oxygen (NBOA calibration method for Raman spectroscopic quantitative analysis of binary alkaline silicate glasses is proposed. By applying ab initio quantum chemistry simulation, Raman optical activities (ROA) of various cluster units consisting of silicon-oxygen tetrahedra (SiOT) with different number of non-bridging oxygen (NBO) can be obtained. Thus, experimental results could be calibrated in order to reflect and represent directly the true relative density of various silicon-oxygen tetrahedra existing inside the silicate glasses. Cation effect on the intensity of Raman bands was also observed and discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1794 (2011)
XPS and Raman Studies of Diamond-Like Carbon Films Prepared by Various Deposition Techniques
YANG Fa-zhan, WANG Shi-qing, SHEN Li-ru, and CHEN Qing-chuan
Diamond-like carbon(DLC) films were deposited on a silicon chip substrate by a metal pulsed magnetic filtered cathodic vacuum arc deposition technique, a direct current magnetron sputtering technique and a pulsed glow discharge plasma enhanced chemical vapor deposition technique. And the characteristics of DLC films weDiamond-like carbon(DLC) films were deposited on a silicon chip substrate by a metal pulsed magnetic filtered cathodic vacuum arc deposition technique, a direct current magnetron sputtering technique and a pulsed glow discharge plasma enhanced chemical vapor deposition technique. And the characteristics of DLC films were investigated using laser Raman spectroscopy and X-ray photoelectron spectroscopy. The spectra of diamond like carbon were collected using Raman spectrometers with 325 nm flters. It was found that DLC films prepared by various deposition technique have different G-peak, D-peak, T-peak, the full width at half maximum(FWHM)of G-peak, D-peak and T-peak, the intensity ratio I(D)/I(G) and I(T)/I(G) and the sp3 content. Among them, the films grown by metal pulsed magnetic filtered cathodic vacuum arc deposition technique have the largest G-peak wave number and the intensity ratio I(T)/I(G), the minimum of the intensity ratio I(D)/I(G), G-FWHM and the maximum sp3 content； those grown by the direct current magnetron sputtering technique have the 2nd largest G-peak wave number, the intensity ratio I(D)/I(G) and I(T)/I(G) and sp3 content, however, they have the largest G-FWHM, while those grown by the pulsed glow discharge plasma enhanced chemical vapor deposition technique have the minimum G-peak wave number and the intensity ratio I(T)/I(G) and sp3 content, and the maximum intensity ratio I(D)/I(G)..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1800 (2011)
The Study of Vibrational Spectra of 3-Amino-2, 5-Dichlorobenzoic Acid by Density Functional Theory
YANG Shui-jiao, GAO Ai-hua, HU Shang-bin, HE Xiao-qing, JIANG Zhen-yi, and CHU San-yang
To understand the relationship between the vibrational spectra and the geometry structure of 3-amino-2,5-dichlorobenzoic acid (3A2,5DBA) essentially, geometry optimizations and vibrational frequencies calculation of 3A2, 5DBA were performed at Hartree-Fock (HF) and Becke’s three-parameter hybrid functional (B3) for theTo understand the relationship between the vibrational spectra and the geometry structure of 3-amino-2,5-dichlorobenzoic acid (3A2,5DBA) essentially, geometry optimizations and vibrational frequencies calculation of 3A2, 5DBA were performed at Hartree-Fock (HF) and Becke’s three-parameter hybrid functional (B3) for the exchange part and the Lee-Yang-Parr (LYP) correlation function (B3LYP) level using 6-311G(d, p) basis set, respectively. The structural information and 45-complete normal vibrational modes of 3A2, 5DBA were obtained. Comparing the computational geometric parameters of 3A2,5DBA with the values observed in experimental measurement of benzoic acid as well as the computed vibrational frequencies of 3A2, 5DBA with the reported data of pertinent literature, it was revealed that the results coming from B3LYP/6-311G(d, p) are more reasonable than those by HF/6-311G(d, p). Taking into account the difference between the computed 3A2, 5DBA molecule and the experimental measured sample, the calculated vibrational frequencies were reasonably scaled. Under the B3LYP/6-311G(d, p) method, the scale factor was 1.001 3 for the vibrational frequencies with wave numbers＜800 cm-1, while the scale factor was 0.961 3 for the vibrational frequencies with wave numbers＞800 cm-1. With the help of Gaussian View software package, the theoretically calculated vibrational frequencies were assigned much more accurately. In addition, the vibrational analysis of substitutive groups and main functional groups of 3A2, 5DBA was carried out. Through the comparison of the calculated vibrational frequencies with the frequencies of 3A2, 5DBA observed in FTIR experiment, the authors found that the theoretically calculated vibrational frequencies scaled reasonably were in excellent agreement with the data coming from experimental measurements. Meanwhile, according to the related literature reports, it was shown that our work done in the paper about vibrational assignments and vibrational analysis of 3A2, 5DBA turned out to be reasonable..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1804 (2011)
Terahertz Spectroscopic Testing of Food Additive Tert-Butylhydroquinone
ZHANG Man, CAI He, and SHEN Jing-ling
Terahertz time-domain spectroscopy (THz-TDS) technique has a wide range of applications in nondestructive testing. After many years study, people have found that many materials have characteristic absorptions in terahertz range. This letter studies the THz spectra of tert-butylhydroquinone (TBHQ), a food additive that Terahertz time-domain spectroscopy (THz-TDS) technique has a wide range of applications in nondestructive testing. After many years study, people have found that many materials have characteristic absorptions in terahertz range. This letter studies the THz spectra of tert-butylhydroquinone (TBHQ), a food additive that was reported excessively in Mak chicken of McDonald. The authors applied terahertz nondestructive testing technique in identifying this material, testing the absorption and refractive index. The absorption spectra of TBHQ and flour mixture in 0.2~2.2 THz were also investigated. The simulation of vibration for single molecular was undertaken. The results represent that this method is possible by comparing the difference in absorption lines and this method paves the way for detecting food additives..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1809 (2011)
Absorption Line Profile Recovery Based on TDLS and MEMS Micro-Mirror for Photoacoustic Gas Sensing
LI Li, Norhana Arsad, George Stewart, Graham Thursby, Deepak Uttamchandani, Brian Culshaw, and WANG Yi-ding
A novel and efficient absorption line recovery technique is presented. A micro-electromechanical systems (MEMS) mirror driven by an electrothermal actuator is used to generate laser intensity modulation through the mirror reflection. Tunable diode laser spectroscopy (TDLS) and photoacoustic spectroscopy (PAS) are used A novel and efficient absorption line recovery technique is presented. A micro-electromechanical systems (MEMS) mirror driven by an electrothermal actuator is used to generate laser intensity modulation through the mirror reflection. Tunable diode laser spectroscopy (TDLS) and photoacoustic spectroscopy (PAS) are used to recover the target absorption line profile which is compared with the theoretical Voigt profile. The target gas is 0.01% acetylene (C2H2) in a nitrogen host gas. The laser diode wavelength is swept across the P17 absorption line of acetylene at 1 535.4 nm by a current ramp, and an erbium-doped fibre amplifier (EDFA) is used to enhance the optical intensity and increase the signal-to-noise ratio (SNR). A SNR of about 35 is obtained with 100 mW laser power from the EDFA. Good agreement is achieved between the experimental results and the theoretical simulation for the P17 absorption line profile..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1814 (2011)
Researches on the Effect of Gas Humidity on Photoacoustic Spectroscopy Gas Detection System
MENG Gui, LIU Xian-yong, YUAN Chang-ying, GUO Feng, ZHENG Cheng-kun, and PENG Chen
Environmental influence is the important factor in a photoacoustic spectroscopy gas detection (PASGD) system when it is applied in the industrial field. The experiments show that the sensitivity of condenser microphone is affected mostly by the humidity of the gas under test, leading to the PASGD’s result drift. The prEnvironmental influence is the important factor in a photoacoustic spectroscopy gas detection (PASGD) system when it is applied in the industrial field. The experiments show that the sensitivity of condenser microphone is affected mostly by the humidity of the gas under test, leading to the PASGD’s result drift. The present paper puts forward a method to eliminate the influence of gas humidity. A speaker is fixed in the photoacoustic cell, whose amplitude is regarded as the sensitivity self-adaption characterization of sound sensor, used to correct the photoacoustic signal amplitude. Thus the problem of sensitivity changing in sound detection with condenser microphone is solved. Based on this method, a photoacoustic experimental setup, equipped with a diode laser, a resonant photoacoustic cell and a lock-in amplifier, was applied to compare the test for different humidity samples. The results show that this method is useful to eliminating the gas humidity influence and enhancing environmental adaptability of PASGD system..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1819 (2011)
Study of Three-Dimensional Fluorescence Spectra for Measuring Chlorobenzene in Water
YU Hai-bin, WANG Ye-yao, and SONG Cun-yi
Quantitative analysis of chlorobenzene (CB) in water by three-dimensional fluorescence spectrometry was discussed in the present paper. The study showed that there is only one fluorescence peak for CB which lies in the range of excitation wavelength (λex) 210～240 nm and emission wavelength (λem) 330～370 nm. When measurQuantitative analysis of chlorobenzene (CB) in water by three-dimensional fluorescence spectrometry was discussed in the present paper. The study showed that there is only one fluorescence peak for CB which lies in the range of excitation wavelength (λex) 210～240 nm and emission wavelength (λem) 330～370 nm. When measuring CB solution of concentration 0.002~0.05 mg·L-1, the fluorescence intensity was the strongest as λex/λem was 225/340 nm, which presented linear correlation with concentration, and the related coefficient was 0.999 67. The study proved that three-dimensional fluorescence spectrometry can be adopted for quantitative analysis of CB in water. With this method, the detection limit was 3.68×10-6 mg·L-1 and the standard deviation was 0.04% at 90% confidence level..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1823 (2011)
Application of Chemometric Methods in Three-Dimensional Fluorescence Spectral Analysis
GAI Yun, BAO Cheng-man, YE Shu-ming, and CHEN Hang
With the increasing complexity of analytical data, traditional data processing methods for spectral analysis can not meet the analysis needs. The chemometrics uses methods of mathematics, statistics and computer sciences to design optimum chemical measurement procedures and to provide maximum information about fluorescWith the increasing complexity of analytical data, traditional data processing methods for spectral analysis can not meet the analysis needs. The chemometrics uses methods of mathematics, statistics and computer sciences to design optimum chemical measurement procedures and to provide maximum information about fluorescence spectrum by analyzing data. In the present paper, the main kinds of three-dimensional fluorescence spectrum, which are widely analyzed by chemometric methods, were illustrated at first. Secondly, an overview of the chemometric methods such as statistical methods, pattern recognition, neural network and the second-order calibration methods is presented. And the applications of these methods are followed by. Finally, the prospect of chemometric methods applied in multidimensional spectral analysis is discussed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1828 (2011)
Design and Synthesis of Imine Compound for Metal Cation Logical Gates Recognition and Setup of Double-Control Fluorescent Molecule Switch
HUANG Tao, ZHU Yu-lian, DAI Xue-qin, ZHANG Qi, and HUANG Yan
The Schiff base’s reduced product N,N-bis(4-methoxybenzyl) ethane-1,2-diamine, which was used as a receptor L, was designed and synthesized for the first time in the present article. It was found that Cu2+ and Fe3+ could quench L in fluorescence observably and Zn2+ and Cd2+ could enhance L remarkably. So the two pair mThe Schiff base’s reduced product N,N-bis(4-methoxybenzyl) ethane-1,2-diamine, which was used as a receptor L, was designed and synthesized for the first time in the present article. It was found that Cu2+ and Fe3+ could quench L in fluorescence observably and Zn2+ and Cd2+ could enhance L remarkably. So the two pair metal cation could set up “OR” logical gate relation with the receptor molecule L, then a logical recognition system be formed. The data of resolved ZnL’s single crystal indicated that ZnL belonged to monoclinic (CCDC No.747994). Integrated spectrum instrument was used to characterize the structure of its alike series of complex compound. According to ZnL’s excellent fluorescence character and the ability to exchange with contiguous metal cation, Zn2+/ZnL/Co2+, Zn2+/ZnL/Ni2+ fluorescent molecule switch was designed. It is hoped that the work above could be positive for the development of molecule computer, bio-intellectualized inspection technology (therapy) and instrument..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1834 (2011)
Studies on the Oxidation of Tyrosine Induced by Hydroxyl Radical with Fluorescence Spectroscopic Method
SUN Yan-hui, WANG Wei-long, WU Lin-sheng, and JIA Xiao-li
Dityrosine is a marker of tyrosine oxidation. To study effecting factors of hydroxyl radical on tyrosine oxidation, synchronous fluorescence spectra with two dimensional correlation was used. The results showed that the peak position and intensity of dityrosine changed while pH value varied. In the system of tyrosine oDityrosine is a marker of tyrosine oxidation. To study effecting factors of hydroxyl radical on tyrosine oxidation, synchronous fluorescence spectra with two dimensional correlation was used. The results showed that the peak position and intensity of dityrosine changed while pH value varied. In the system of tyrosine oxidation, with the increment of tyrosine concentration, the concentration of dityrosine decreased. With the increment of hydrogen peroxide concentration, the concentration of dityrosine increased. The oxidation reaction was prone to taking place in acid conditions while difficult to develop in basic conditions. With the development of oxidation reaction, the fluorescence intensity of dityrosine increased and then decreased. Two dimentional correlation synchronous fluorescence spectra showed that the variation in the intensity at 292 nm preceded that of 281 , 300 and 374 nm. Thus, fluorescence spectroscopy was simple and easy for studying tyrosine oxidation induced by hydroxyl radical..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1838 (2011)
New Methods and Technologies Expandable to the Laser Detection of Biological and Medical Samples
SHI Gui-zhen, DU Hai, GE Liao-hai, TIAN Yu, HUANG Mao-cheng, and WANG Wen-yun
The multicolour three-photon resonant photoionization spectra and high-time-resolved laser spectrum of UI were measured with a setup composed of a Nd∶YAG-laser(532 nm, operated at 10 Hz)-pumped pulsed tunable dye laser system, a time-of-flight mass spectrometer, including micro-channel plate components, ns-oscilloscopeThe multicolour three-photon resonant photoionization spectra and high-time-resolved laser spectrum of UI were measured with a setup composed of a Nd∶YAG-laser(532 nm, operated at 10 Hz)-pumped pulsed tunable dye laser system, a time-of-flight mass spectrometer, including micro-channel plate components, ns-oscilloscope, boxcar integrator, and so on. Creative inventions of this paper are for the first time by laser-induced quantum population of the graphic method, the causes for single-colour and two-colour three-photon resonant photoionization spectra peak were given in the three-colour three-photon resonant photoionization experiment； The question how to avoid producing single-colour and two-colour three-photon resonant photoionization spectra peak was solved, That is, how to solve the problem to avoid “false peaks”, so that multicolour three-photon resonant photoionization purity was raised remarkably; On this basis, not only in close proximity to energy level position with just a difference 0.642 cm-1, the isotopes A and B of uranium, which are difficult to distinguish, were well resolved, but the two excited state lifetime values were obtained respectively. This technology is not limited to uranium spectrum, but more importantly, it’s versatile. The new methods and technologies of basic research can be expanded to samples of biological and medical research fields with laser detecting and analysis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1842 (2011)
Multi-Population Elitists Shared Genetic Algorithm for Outlier Detection of Spectroscopy Analysis
CAO Hui, and ZHOU Yan
The present paper proposed an outlier detection method for spectral analysis based on multi-population elitists shared genetic algorithm. The method was exploited in the NIR data set analysis to remove the outliers from the data set, and partial least squares (PLS) was combined with the proposed method to build a prediThe present paper proposed an outlier detection method for spectral analysis based on multi-population elitists shared genetic algorithm. The method was exploited in the NIR data set analysis to remove the outliers from the data set, and partial least squares (PLS) was combined with the proposed method to build a prediction model. In contrast with Monte Carlo cross validation, leave-one-out cross validation, Mahalanobis-distance and traditional genetic algorithm for outlier detection, the prediction residual error sum of squares (PRESS) for moisture prediction model based on the proposed method decreases in the rate of 72.4%, 39.5%, 39.5% and 14.5%; the PRESS value for fat prediction model decreases in the rate of 86.2%, 75.9%, 84.9% and 19.9%; and the PRESS value for protein prediction model decreases in the rate of 56.5%, 35.7%, 35.7% and 18.2% respectively. Results indicated that the method is applicable for spectral outlier detection for different species, and the model based on the data set without the removed outliers is more accurate and robust..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1847 (2011)
Spectroscopy Study on the Selectively Distinguishing Cefalexin with the Molecular Imprinted Polymer
JIANG Yu-xiang, PANG Dao-lin, HE Qiang, LAI Cheng-yue, ZHENG Huai-li, and LI Fang
Molecular imprinted polymers of cefalexin (CFL) were prepared by non-covalent molecular imprinting technique in the present paper. Using CFL as template molecule, acrylamide (AM) or methacrylic acid (MAA) as functional monomer, ethylene dimethacrylate (EGDMA) as cross-linker, AIBN as initiator and methanol as porogen aMolecular imprinted polymers of cefalexin (CFL) were prepared by non-covalent molecular imprinting technique in the present paper. Using CFL as template molecule, acrylamide (AM) or methacrylic acid (MAA) as functional monomer, ethylene dimethacrylate (EGDMA) as cross-linker, AIBN as initiator and methanol as porogen agent, different molecularly imprinted polymers (MIPs) of CFL were synthesized by bulk or suspension polymerization as synthetic method. The intermolecular action between AM and CFL was investigated by UV and IR spectrophotometric analysis, and the results indicated that polymerizing functional monomer AM could bond effectively with template molecule CFL. By using UV spectrophotometric analysis method, it was found that the MIP prepared with AM-EGDMA by bulk polymerization showed the highest binding capacity for CFL. Test of selective adsorption made clear that the MIP represented more excellent identification property to CFL than to cefadroxol and ampicillin. The MIPs were used as solid-phase extraction sorbent for extraction and enrichment of CFL in actual samples. And the recoveries for CFL extraction were found to be 99.3%～99.7%(n=3), demonstrating the feasibility of the prepared MIPs for CFL extraction..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1852 (2011)
Single-Trial Estimation of Dynamic Spectrum
LI Gang, XIONG Chan, WANG Hui-quan, LIN Ling, ZHANG Bao-ju, and TONG Ying
To improve the efficiency and accuracy of the dynamic spectrum data processing, the method of single-trial estimation was adopted. First, the rising edge of the whole band PPG was extracted, which was calculated by averaging superimposed collected photoelectric plethysmography (PPG) at all wavelengths as a template perTo improve the efficiency and accuracy of the dynamic spectrum data processing, the method of single-trial estimation was adopted. First, the rising edge of the whole band PPG was extracted, which was calculated by averaging superimposed collected photoelectric plethysmography (PPG) at all wavelengths as a template per single pulse; Second, this template was used to correct the rising edge of PPG at all wavelengths, and the difference of absorbance was calculate, and then a single-trial DS was obtained; finally, the single-trial DS which contained the gross error under the 3σ criterion was removed, and then the remaining superimposed single-trial DS was averaged as the final output of the DS. Data measured from 10 volunteers were compared with the results of the extraction in frequency domain: the correlation coefficient distribution of the DS from the same finger of the same individual was improved from 0.006 775 to 0.000 384 0; the correlation coefficient distribution of the DS from the different fingers of the same individual was improved from 0.013 93 to 0.002 205, whereas the differences of DS between different individuals were significantly increased. The results show that the method of single-trial estimation can get the DS data more quickly with high quality, and accelerate the process of DS put into practical application..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1857 (2011)
Spectra and Influences of Rayleigh and Stimulated Brillouin Scattering in Fiber-Optic Distributed Disturbance Sensor
ZHANG Chun-xi, LIANG Sheng, FENG Xiu-juan, LIN Wen-tai, LI Chen, LI Qin, ZHONG Xiang, and LI Li-jing
Spectra and influences of Rayleigh backscattering (RB) and stimulated Brillouin scattering (SBS) in the fiber-optic distributed disturbance sensor (FDDS) were investigated. Models of RB, double RB (DRB) and SBS in long fibers were established. By numerical simulation, it was found that optical signal-to-noise ratio is Spectra and influences of Rayleigh backscattering (RB) and stimulated Brillouin scattering (SBS) in the fiber-optic distributed disturbance sensor (FDDS) were investigated. Models of RB, double RB (DRB) and SBS in long fibers were established. By numerical simulation, it was found that optical signal-to-noise ratio is extraordinarily reduced due to SBS and RB, which results in location errors. Numerical results were confirmed by experiments and helpful to improving the location precision for applications with long monitored length..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1862 (2011)
Monitoring Models of the Plant Nitrogen Content Based on Cotton Canopy Hyperspectral Reflectance
WANG Ke-ru, PAN Wen-chao, LI Shao-kun, CHEN Bing, XIAO Hua, WANG Fang-yong, and CHEN Jiang-lu
Cotton production for accurate non-destructive, rapid monitoring of plant nitrogen content there is an urgent demand. Canopy spectral characteristics of the cotton plant and its quantitative relationship between nitrogen content, can achieve non-destructive monitoring of cotton nitrogen. Two consecutive years by differCotton production for accurate non-destructive, rapid monitoring of plant nitrogen content there is an urgent demand. Canopy spectral characteristics of the cotton plant and its quantitative relationship between nitrogen content, can achieve non-destructive monitoring of cotton nitrogen. Two consecutive years by different nitrogen test, cotton canopy hyperspectral data collection and simultaneous determination of canopy nitrogen content, analysis of different fertilizer treatments of cotton canopy spectral characteristics and the relationship between nitrogen content of cotton, the results show that: nitrogen content of cotton plant in different periods and spectral reflectance in the visible band (400～700 nm) was negatively related to the near-infrared 700～1 300 nm band was a significant positive correlation, and in the short-wave infrared 1 300～1 800 nm band correlation is more complicated. Canopy scale, the whole growth stage of cotton, the visible band are sensitive to nitrogen content in cotton band, and near-infrared only is the cotton boll nitrogen content of the sensitive band; short-wave infrared band only in the budding period Cotton nitrogen sensitive band. Using nitrogen-sensitive bands in different periods can be constructed Cotton Cotton Nitrogen monitoring indicators..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1868 (2011)
Based on Moire Interference Accurate Detection of the Laser Center Wavelength
YAN Xiao-yan, QIN Jian-min, WU Jin-hui, and QIAO Ji-ping
To improve spectrum resolution of the traditional Fourier interferometer with the same size lens, was proposed based on orthogonal wedge Fourier interferometer system. The interferometer system gets the optical path difference by the prism of two mutually perpendicular, which can make the laser Interferences on the CCDTo improve spectrum resolution of the traditional Fourier interferometer with the same size lens, was proposed based on orthogonal wedge Fourier interferometer system. The interferometer system gets the optical path difference by the prism of two mutually perpendicular, which can make the laser Interferences on the CCD Array. The detector use the area array CCD linear array CCD, and the system collected the interference fringes on the Two-dimensional plane. On the basis of the spectrum distribution of orthogonal inclination Moire interferometer by calculating optical path difference function, the system made the splicing of interference fringes on the area array CCD and Moire transform, finally got the spectrum resolution. The results from the MATLAB simulation software shows that the Maximum optical path difference of the orthogonal inclination Moire interferometer can be generated up to 234 μm, which is higher than the traditional Fourier interferometer about one order of magnitude, so the spectrum resolution also increased by nearly 10 times theoretical. Experimental calibration of the spectrometer with a selection of LAB SPAKR 750A-type spectrometer, measurements for the center wavelength of 635 nm semiconductor laser, the results show basically the same center wavelength position. However, the spectrum detected by orthogonal inclination Moire interferometer system near the center wavelength is better than the traditional interferometer system..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1873 (2011)
The Design and Implementation of the Web Typical Surface Object Spectral Information System in Arid Areas Based on .NET and SuperMap
XIA Jun, TASHPOLAT·Tiyip, ZHANG Fei, and JI Hong-liang
The characteristic of object spectrum is not only the base of the quantification analysis of remote sensing, but also the main content of the basic research of remote sensing. The typical surface object spectral database in arid areas oasis is of great significance for applied research on remote sensing in soil salinizThe characteristic of object spectrum is not only the base of the quantification analysis of remote sensing, but also the main content of the basic research of remote sensing. The typical surface object spectral database in arid areas oasis is of great significance for applied research on remote sensing in soil salinization. In the present paper, the authors took the Ugan-Kuqa River Delta Oasis as an example, unified .NET and the SuperMap platform with SQL Server database stored data, used the B/S pattern and the C# language to design and develop the typical surface object spectral information system, and established the typical surface object spectral database according to the characteristics of arid areas oasis. The system implemented the classified storage and the management of typical surface object spectral information and the related attribute data of the study areas; this system also implemented visualized two-way query between the maps and attribute data, the drawings of the surface object spectral response curves and the processing of the derivative spectral data and its drawings. In addition, the system initially possessed a simple spectral data mining and analysis capabilities, and this advantage provided an efficient, reliable and convenient data management and application platform for the Ugan-Kuqa River Delta Oasis’s follow-up study in soil salinization. Finally, It’s easy to maintain, convinient for secondary development and practically operating in good condition..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1878 (2011)
Inversion of the Lake Total Nitrogen Concentration by Multiple Regression Kriging Model Based on Hyperspectral Data of HJ-1A
PAN Bang-long, YI Wei-ning, WANG Xian-hua, QIN Hui-ping, WANG Jia-cheng, and QIAO Yan-li
The content of total nitrogen in the waters is an important index to measure lake water quality, and the technique of remote sensing plays a large role in quantitatively monitoring the dynamic change and timely grasping the status of lake pollution. Taking Chaohu as an example, quantitative inversion models of total niThe content of total nitrogen in the waters is an important index to measure lake water quality, and the technique of remote sensing plays a large role in quantitatively monitoring the dynamic change and timely grasping the status of lake pollution. Taking Chaohu as an example, quantitative inversion models of total nitrogen were established by multivariable regression Kriging under analyzing of an correlation between total nitrogen and chlorophyll-a or suspended solids by HIS hyperspectral remote sensing data of HJ-1A satellite. The result shows that the correlation of 0.76 was discovered between total nitrogen and the multiple combination with band 72, band 79 and band 97, while the correlation could be increased to 0.83 by applying combined model of multiple linear regression and ordinary Kriging. The optimization of the residuals of the conventional regression model can improve the accuracy of the inversion effectively. These results also provide useful exploration for further establishing a common model of quantitative inversion of lake total nitrogen concentration..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1884 (2011)
Study on Molecular Spectrum of Fried Linseed Oil
NA Peng-jun, and JIN Xiao-yong
In order to ensure security of fried food and find out regularity of frying oil, the change of linseed oil fried in different time was investigated by three dimensional fluorescence and UV. The experiment results showed that the property of fried oil has not changed obviously in first two hours, but with the prolongatiIn order to ensure security of fried food and find out regularity of frying oil, the change of linseed oil fried in different time was investigated by three dimensional fluorescence and UV. The experiment results showed that the property of fried oil has not changed obviously in first two hours, but with the prolongation of frying time, the fluorescence spectra and UV spectra of fried linseed oil changed immensely after frying for six hours, which indicates that more harmful substances were produced after linseed oil was fried more than six hours..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1889 (2011)
Characteristic Wavelengths Analysis for Remote Sensing Reflectance on Water Surface in Taihu Lake
SHEN Qian, ZHANG Bing, LI Jun-sheng, WU Yuan-feng, WU Di, SONG Yang, ZHANG Fang-fang, and WANG Gan-lin
The research on characteristic wavelengths analysis of reflectance spectrum is a very important and basic task for remote sensing of inland-water color. The present paper analyzed remote sensing reflectances of 312 samples measured in Taihu Lake between 2006 and 2009, and these reflectances were separated into three clThe research on characteristic wavelengths analysis of reflectance spectrum is a very important and basic task for remote sensing of inland-water color. The present paper analyzed remote sensing reflectances of 312 samples measured in Taihu Lake between 2006 and 2009, and these reflectances were separated into three classes by chlorophyll-a concentrations. The reflectance spectra smoothed by Savitzky-Golay algorithm were calculated by first- and second-order derivatives. Then, zero values were located in the derivatives and counted at all wavelengths. Thus the frequency distribution of zeros at each wavelength was got. At which wavelength a local maximum of the frequencies appears a characteristic wavelength will most likely be there. These characteristic wavelengths are corresponding to maximum, minimum, from-concave-to-convex inflection point and from-convex-to-concave inflection point of a spectrum curve. At last the paper provided the characteristic wavelengths for Taihu Lake water at the spectral coverage from 350 to 900 nm, which are 359, 440, 464, 472, 552, 566, 583, 628, 636, 645, 660, 676, 689, 706, 728, 791, 806, and 825 nm. In addition, these wavelengths we found were explained by absorption of phytoplankton pigments and components of water in Taihu Lake. Being able to distinguish overlaps between peaks and vales at the same wavelength in different measurements, the method to analyze characteristic wavelengths is universally applicable to various spectrum curves. The characteristic wavelengths chosen by the paper are helpful to improving some algorithms of retrieval of water quality parameters..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1892 (2011)
Passive SLF Spectrum Analysis for Tracing the Mining Dynamic of CBM
JIANG Hong-bo, QIN Qi-ming, and LI Bai-shou
Exploration and development of the coal-bed methane (CBM) is very important to economics, environment and society. It is a key factor to trace and assess the process of the coal-bed gas mining dynamically for its efficient development. In the present article, based on the theory of natural resources super low frequencyExploration and development of the coal-bed methane (CBM) is very important to economics, environment and society. It is a key factor to trace and assess the process of the coal-bed gas mining dynamically for its efficient development. In the present article, based on the theory of natural resources super low frequency (SLF) electromagnetic detecting, the method that uses the SLF to trace the coal-bed gas mining dynamic is introduced. The field tests in 2007 and 2010 in the QIN-Shui basin, Shanxi province of China indicate that this method is efficient for the dynamic of the coal-bed gas mining..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1898 (2011)
Cross Comparison of ASTER and Landsat ETM+ Multispectral Measurements for NDVI and SAVI Vegetation Indices
XU Han-qiu, and ZHANG Tie-jun
The present paper investigates the quantitative relationship between the NDVI and SAVI vegetation indices of Landsat and ASTER sensors based on three tandem image pairs. The study examines how well ASTER sensor vegetation observations replicate ETM+ vegetation observations, and more importantly, the difference in the vThe present paper investigates the quantitative relationship between the NDVI and SAVI vegetation indices of Landsat and ASTER sensors based on three tandem image pairs. The study examines how well ASTER sensor vegetation observations replicate ETM+ vegetation observations, and more importantly, the difference in the vegetation observations between the two sensors. The DN values of the three image pairs were first converted to at-sensor reflectance to reduce radiometric differences between two sensors, images. The NDVI and SAVI vegetation indices of the two sensors were then calculated using the converted reflectance. The quantitative relationship was revealed through regression analysis on the scatter plots of the vegetation index values of the two sensors. The models for the conversion between the two sensors, vegetation indices were also obtained from the regression. The results show that the difference does exist between the two sensors, vegetation indices though they have a very strong positive linear relationship. The study found that the red and near infrared measurements differ between the two sensors, with ASTER generally producing higher reflectance in the red band and lower reflectance in the near infrared band than the ETM+ sensor. This results in the ASTER sensor producing lower spectral vegetation index measurements, for the same target, than ETM+. The relative spectral response function differences in the red and near infrared bands between the two sensors are believed to be the main factor contributing to their differences in vegetation index measurements, because the red and near infrared relative spectral response features of the ASTER sensor overlap the vegetation “red edge” spectral region. The obtained conversion models have high accuracy with a RMSE less than 0.04 for both sensors’ inter-conversion between corresponding vegetation indices..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1902 (2011)
Monte-Carlo Algorithm for Phase Function of Medium Scattering in Radiative Heat Transfer
DU Yong-cheng, and YANG Li
Phase function of the compley distributed systems is the significant parameter in the field of radiative heat transfer in medium. The Monte-Carlo method has the advantages of both numerical algorithm and experiment measurement. Multiple scattering phase function of the complex distributed systems based on the Monte-CarPhase function of the compley distributed systems is the significant parameter in the field of radiative heat transfer in medium. The Monte-Carlo method has the advantages of both numerical algorithm and experiment measurement. Multiple scattering phase function of the complex distributed systems based on the Monte-Carlo method overcomes the former deficiency and expresses the influence of the multiple scattering, also, it can calculate phase functions of any controlled volume. According to a number of mathematical experiments, the larger the density of the medium is the better-proportioned the scattered energy is in the 4π solid space..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1908 (2011)
Validation and Analysis of Water Column Correction Algorithm at Sanya Bay
YANG Chao-yu, YANG Ding-tian, YE Hai-bin, and CAO Wen-xi
Water column correction has been a substantial challenge for remote sensing. In order to improve the accuracy of coastal ocean monitoring where optical properties are complex, optical property of shallow water at Sanya Bay and the suitable water column correction algorithms were studies in the present paper. The authorWater column correction has been a substantial challenge for remote sensing. In order to improve the accuracy of coastal ocean monitoring where optical properties are complex, optical property of shallow water at Sanya Bay and the suitable water column correction algorithms were studies in the present paper. The authors extracted the bottom reflectance without water column effects by using a water column correction algorithm which is based on the simulation of the underwater light field in idealized water. And we compared the results which were calculated by the model and Christian’s model respectively. Based on a detailed analysis, we concluded that: Because the optical properties of Sanya Bay are complex and vary greatly with location, Christian’s model lost its advantage in the area. Conversely, the bottom reflectance calculating by the algorithm based on the simulation of the underwater light field in idealized water agreed well with in situ measured bottom reflectance, although the reflectance was lower than in situ measured reflectance value between 400 and 500 nm. So, it is reasonable to extract bottom information by using the water column correction algorithm in local bay area where optical properties are complex..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1912 (2011)
Preparation and Structural Analysis of Diatomite-Supported SPFS Flocculant
ZHENG Huai-li, FANG Hui-li, JIANG Shao-jie, YANG Chun, MA Jiang-ya, and ZHANG Zhao-qing
In the presetn study, polymerized ferric sulphate (PFS) flocculant was prepared and tested. In the preparation of PFS flocculant, industrial by-product ferrous sulfate heptahydrate (FeSO4·7H2O) was reused as the main material. By composition with diatomite and drying up at certain temperature in vacuum drying ovenIn the presetn study, polymerized ferric sulphate (PFS) flocculant was prepared and tested. In the preparation of PFS flocculant, industrial by-product ferrous sulfate heptahydrate (FeSO4·7H2O) was reused as the main material. By composition with diatomite and drying up at certain temperature in vacuum drying oven, solid PFS flocculant was produced. Structural characteristics of the new flocculant product were examined through infrared spectroscopy and scanning electron microscopy (SEM), which showed that by compositing with diatomite, new group bridging emerged in the structure of PFS, which made the bond of groups stronger. In addition, part of the metalic contents in diatomite was polymerized with PFS, the product of which was polymerized ferric complex. Furthermore, the absorbing and agglomerating capacity of the diatomite carrier was significant. Considering the factors listed above, the new solid polymerized ferric sulphate (SPFS) flocculant was characterized with a larger molecule structure and enhanced absorbing, bridging and rolling sweep capacities. Through orthogonal experiment, optimum conditions of synthesis were as follows: the ratio of FeSO4·7H2O/diatomite in weight was 43/1, the reaction time is 1 h and the reaction temperature is 55 ℃. By wastewater treatment experiment, it was found that the synthetic products showed good flocculation performance in the treatment of domestic sewage, the removal of COD was 80.00% and the removal of turbidity was 99.98%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1917 (2011)
Study on Chemical Compositions and Crystallinity Changes of Bamboo Treated with γ Rays
SUN Feng-bo, JIANG Ze-hui, FEI Ben-hua, LU Fang, YU Zi-xuan, and CHANG Xiang-zhen
The structures and qualities of main chemical compositions in cell wall of bamboo treated with γ rays were tested by nuclear magnetic resonance spectrometer (NMR) and X-ray Diffraction (XRD). The result indicated that the bamboo crystallinity increased at the beginning of irradiation process, while the crystallinity reThe structures and qualities of main chemical compositions in cell wall of bamboo treated with γ rays were tested by nuclear magnetic resonance spectrometer (NMR) and X-ray Diffraction (XRD). The result indicated that the bamboo crystallinity increased at the beginning of irradiation process, while the crystallinity reduced when the irradiation dose was raised to about 100 kGy. During the whole irradiation process, hemicellulose degraded, and with the irradiation doses increased the non-phenolic lignin changed to the phenolic..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1922 (2011)
Study on Spatial Interpolation of the Average Temperature in the Yili River Valley Based on DEM
CHEN Dong-hua, ZOU Chen, WANG Su-ying, LI Hu, and ZHANG Xin-shi
On the basis of the monthly mean temperature data of 19 meteorological stations from 1961 to 2008 in the Yili River Valley, the correlation between mean annual temperature and elevation was analyzed to get access to the temperature lapse rate of 0.564 ℃/100 m. The main purpose of this study was to apply a spatial interOn the basis of the monthly mean temperature data of 19 meteorological stations from 1961 to 2008 in the Yili River Valley, the correlation between mean annual temperature and elevation was analyzed to get access to the temperature lapse rate of 0.564 ℃/100 m. The main purpose of this study was to apply a spatial interpolation method based on DEM and compare with the traditional ones of inverse distance weight (IDW) and Kriging methods. According to the cross-validation results, it was concluded that the accuracy of interpolation method based on DEM was superior to the other two methods. Combined with DEM data, the mean annual temperature distribution map with 90 m resolution was established and it expressed the main trend of temperature changing with terrain and reflected the spatial variability of temperature..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1925 (2011)
Determination of Soil Available Nutrient Contents Using Multi-Element Hollow Cathode Lamp
LU Shao-kun, HE Dong-xian, HU Juan-xiu, and WANG Yu-chang
The soil available nutrient determination based on atomic absorption spectrometry using multi-element hollow cathode lamp (HCL) is improved from the instrument using single-element HCLs via modifying the software and hardware. As a test, available Cu, Fe, Zn, Mg and Ca contents of 30 fluvo-aquic soil samples measured bThe soil available nutrient determination based on atomic absorption spectrometry using multi-element hollow cathode lamp (HCL) is improved from the instrument using single-element HCLs via modifying the software and hardware. As a test, available Cu, Fe, Zn, Mg and Ca contents of 30 fluvo-aquic soil samples measured by atomic absorption spectrometry using a multi-element HCL were compared with that measured by using single-element HCLs for 3 replications. A significant linear relationship with the slope close to 1 was found in soil available Cu, Fe, Zn and Ca contents measured by using multi-element HCL and single-element HCLs. The linear correlation coefficient of 0.86 and the slope of 0.85 were found in soil available Mg content. No significant difference was revealed from the above comparison data via analysis of variance. Therefore, the soil available nutrient determination based on atomic absorption spectrometry using multi-element HCL has the same measurement accuracy and is 50%～60% time-saving compared to that by using single-element HCLs..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1930 (2011)
Application of ICP-MS/ICP-AES to Detecting Nutrition and Heavy Metal Contents in Grain of Detached Wheat Spikes in Vitro Culture
ZHANG Dai-jing, JIANG Li-na, ZHANG Zhi-juan, SHAO Yun, and LI Chun-xi
The heavy metals in the environment led to the defect of nutrient contents in grains and metabolic disturbance seriously. In order to research the effect of heavy metal copper and cadmium on nutrient contents and heavy metal contents of wheat grain, the present paper studied the nutrition element (P, K, Ca, Mg, Na, Fe,The heavy metals in the environment led to the defect of nutrient contents in grains and metabolic disturbance seriously. In order to research the effect of heavy metal copper and cadmium on nutrient contents and heavy metal contents of wheat grain, the present paper studied the nutrition element (P, K, Ca, Mg, Na, Fe, Mn, Zn and B) and contents of heavy metal (Pb, Cr, Hg, Cu and Cd) in organs of detached wheat spikes in vitro culture by ICP-MS/ICP-AES. The results showed that the weight of grain reduced significantly with copper and cadmium treatment. Under different copper treatment, the contents of P, K, Mg, Ca, Na, Mn and Zn increased, but Fe and B contents reduced. Exogenous cadmium promoted the absorption of P, K, Ca, Mg and Mn while interrupted the absorption of Na, Fe, Zn and B. Exogenous copper and cadmium treatment reduced the Hg content in wheat grain, but the Cu and Cd contents were 55-folds and 62 folds of the national food sanitation standard. All the data showed that the effects of copper and cadmium are disadvantageous to the accumulation of nutrient and heavy metal contents..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1935 (2011)
Determination and Correlation Analysis of Trace Elements in Boletus Tomentipes
LI Tao, WANG Yuan-zhong, ZHANG Ji, ZHAO Yan-li, and LIU Hong-gao
The contents of eleven trace elements in Boletus tomentipes were determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The results showed that the fruiting bodies of B. tomentipes were very rich in Mg and Fe (>100 mg·kg-1) and rich in Mn, Zn and Cu (>10 mg·kg-1). Cr, Pb, Ni, CThe contents of eleven trace elements in Boletus tomentipes were determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The results showed that the fruiting bodies of B. tomentipes were very rich in Mg and Fe (>100 mg·kg-1) and rich in Mn, Zn and Cu (>10 mg·kg-1). Cr, Pb, Ni, Cd, and As were relatively minor contents (0.1～10.0 mg·kg-1) of this species, while Hg occurred at the smallest content (<0.1 mg·kg-1). Among the determined 11 trace elements, Zn—Cu had significantly positive correlation (r=0.659, P<0.05), whereas, Hg—As, Ni—Fe, and Zn—Mg had significantly negative correlation (r=－0.672, －0.610, －0.617, P<0.05). This paper presented the trace elements properties of B. tomentipes, and is expected to be useful for exploitation and quality evaluation of this species..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1939 (2011)
Determination of Trace Elements Be, Cd, As and Pb in Air of Residential Areas by Inductively Coupled Plasma-Mass Spectrometry Coupled with Ultrasonic Leaching
CHEN Xi, DING Liang, HE Gong-li, XU Xiao-ya, ZHANG Miao, XU Dong-qun, and LIN Shao-bin
In the present paper, the method for determining the trace elements Be, Cd, As and Pb in air of residential areas by inductively coupled plasma-mass spectrometry was established. Ultrasonic leaching procedures were applied to extract the trace elements from the filter membrane of the atmospheric particulates. The operaIn the present paper, the method for determining the trace elements Be, Cd, As and Pb in air of residential areas by inductively coupled plasma-mass spectrometry was established. Ultrasonic leaching procedures were applied to extract the trace elements from the filter membrane of the atmospheric particulates. The operating condition of the instrument was optimized. 72Ge, 115In and 204Tl were chosen as the internal elements and the effect of matrix, interface and fluctuation of instrument was overcome effectively. Satisfactory linearity of working curves of four elements was obtained, giving all the correlation coefficients over 0.999 5, and the detection limit of the method was between 0.006 and 0.045 ng·m-3. The mean values of National Standard Reference Material GBW(E)080212 were in agreement with the certified values. The sampling filters membranes, divided into four equal parts and with added standard solution with different concentions were analyzed, and the recovery rate of samples were in the range of 91.6%～109.7% with the related standard deviation between 0.7% and 4.8%. The obtained results showed that the method of determining the trace elements Be, Cd, As and Pb in air of residential areas by inductively coupled plasma-mass spectrometry proved to be simple, accurate, sophisticated and stable..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1942 (2011)
Determination of Trace Silver in Water Samples by Solid Phase Extraction Portable Tungsten-Coil Electrothermal Atomic Absorption Spectrometry
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
A simple method has been developed for the determination of silver in environmental water samples using solid phase extraction with tungsten-coil electrothermal atomic absorption spectrometry. Silica gel was used as an adsorbent and packed into a syringe barrel for solid phase extraction of silver prior to its determinA simple method has been developed for the determination of silver in environmental water samples using solid phase extraction with tungsten-coil electrothermal atomic absorption spectrometry. Silica gel was used as an adsorbent and packed into a syringe barrel for solid phase extraction of silver prior to its determination by using a portable tungsten-coil electrothermal atomic absorption spectrometer. Optimum conditions for adsorption and desorption of silver ion, as well as interferences from co-existing ions, were investigated. A sample pH value of 6.0, a sample loading flow rate of 4.0 mL·min-1, and the mixture of 4%(m/v) thiourea and 2%(φ) nitrate acid with the eluent flow rate of 0.5 mL·min-1 for desorption were selected for further studies. Under optimal conditions, a linear range of 0.20～4.00 ng·mL-1, a limit of detection (3σ) of 0.03 ng·mL-1 and a preconcentration factor of 94 were achieved. The proposed method was validated by testing three environmental water samples with satisfactory results..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1946 (2011)
Determination of Total Mercury and Ionic Mercury in Artificial Gastric Juice of Tibetan Medicine Dangzuo by GAE-AFS
LI Cen, YANG Hong-xia, WEI Li-xin, DU Yu-zhi, and ZHANG Guo-ying
The mercury in Tibetan medicine has become important focus in the research on medicine safety evaluation. The total mercury and the ionic mercury in artificial gastric juice of Tibetan medicine Dangzuo were detected by Gold Amalgam Enrichment-Atomic Fluorescence Spectrometry (GAE-AFS). In the present study, Tibetan medThe mercury in Tibetan medicine has become important focus in the research on medicine safety evaluation. The total mercury and the ionic mercury in artificial gastric juice of Tibetan medicine Dangzuo were detected by Gold Amalgam Enrichment-Atomic Fluorescence Spectrometry (GAE-AFS). In the present study, Tibetan medicine Dangzuo was prepared by H2SO4-KNO3 digestion system and artificial gastric juice. The established method and condition of instrument were investigated. Under the optimum experimental conditions and instrumental operation parameters, the recovery(n=6)of HgS is 99.56 % (RSD=1.94%), the limit of detection for mercury is 0.2 ng·L-1, the linear range is 0～500 ng·L-1, and r=0.999 9. Then, the total mercury and the ionic mercury in artificial gastric juice in Dangzuo samples from different Tibetan regions were assayed. The result showed that the ranges of total mercury and ionic mercury in artificial gastric juice were 3.998 0～16.735 8 mg·g-1 and 45.537 7～1 033.985 0 ng·g-1, respectively. The analytical method mentioned above is rapid and accurate for determining the amount of mercury in Tibetan medicine Dangzuo..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1950 (2011)
Influence of Ancient Glass Samples Surface Conditions on Chemical Composition Analysis Using Portable XRF
LIU Song, LI Qing-hui, and GAN Fu-xi
Portable X-ray fluorescence analysis (PXRF) is one kind of surface analysis techniques, and the sample surface condition is an important factor that influences the quantitative analysis results. The ancient glass samples studied in the present paper were excavated from Xinjiang, Guangxi, Jiangsu provinces, and they belPortable X-ray fluorescence analysis (PXRF) is one kind of surface analysis techniques, and the sample surface condition is an important factor that influences the quantitative analysis results. The ancient glass samples studied in the present paper were excavated from Xinjiang, Guangxi, Jiangsu provinces, and they belong to Na2O-CaO-SiO2, K2O-SiO2, and PbO-BaO-SiO2 system, respectively. Quantitative analysis results of weathered surface and inside of the ancient glass samples were compared. The concentration change of main fluxes in different parts of the samples was pointed out. Meanwhile, the authors studied the effect of distance between the sample and the reference plane, and curve shape of the sample on the quantitative results. The results obtained were calibrated by three methods, and the validity of these three methods was proved. Finally, the normalizing method was proved to be a better method for quantitative analysis of antiques. This paper also has guiding significance for chemical composition analysis of ancient jade samples using PXRF..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1954 (2011)
Nondestructive Analysis of Some Ancient Glass in Jin and Yuan Dynasty, by EDXRF Probe
LI Qing-lin, XU Cheng-tai, LING Xue, and YAO Zheng-quan
The chemical composition of some glass samples in Jin and Yuan Dynasty were analyzed by EDXRF, to discuss the technological character of these glass samples. The result shows that the chemical composition of these glass samples is very complex. According to the chemical composition, these glass samples include K2O-CaO-The chemical composition of some glass samples in Jin and Yuan Dynasty were analyzed by EDXRF, to discuss the technological character of these glass samples. The result shows that the chemical composition of these glass samples is very complex. According to the chemical composition, these glass samples include K2O-CaO-SiO2, Na2O-CaO-SiO2 and K2O-CaO-PbO-SiO2 glass, and a crystal SiO2 sample which was once considered a glass sample. The reason for the color of all blue glass samples is the existence of CuO, but not CoO..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1960 (2011)
Preparation of Electrodeposited Cr-La Coating and Its Spectral Properties
LIU Xiao-zhen, WANG Gang, SONG Ling-ling, LI Xin, and ZHU Xu-qiang
Cr-La coating(dc) and Cr-La coating(pulse) were prepared by electrodeposition method of direct current and pulsating current respectively. The Cr-La coating (dc) and Cr-La coating (pulse) were characterized with ICP-AES, EDAX, XRD and SEM techniques, respectively. Cr-La coating(dc) was amorphous. There were crystallineCr-La coating(dc) and Cr-La coating(pulse) were prepared by electrodeposition method of direct current and pulsating current respectively. The Cr-La coating (dc) and Cr-La coating (pulse) were characterized with ICP-AES, EDAX, XRD and SEM techniques, respectively. Cr-La coating(dc) was amorphous. There were crystalline La and CrC in Cr-La coating(pulse). The microhardness of the Cr-La coating(dc) and Cr-La coating(pulse) were as high as 860.3 and 930.2 HV respectively, which were higher 11.15% and 20.18% higher than that of the Cr coating (774.0 HV). The wear weight losses of Cr-La coating(dc) and Cr-La coating(pulse) were 1.29 and 2.25 times lower than that of Cr coating, respectively. The friction coefficient of Cr coating, Cr-La coating(dc) and Cr-La coating(pulse) were 0.884, 0.640 and 0.648 respectively. The properties of wear weight loss and microhardness of coatings were improved with pulsating current. The wear weight loss and microhardness of Cr-La coating(pulse) were lower 1.75 time lower and higher 8.13% higher than that of the Cr-La coating(dc), respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1964 (2011)
Advance in Imaging Spectropolarimeter
WANG Xin-quan, XIANGLI Bin, HUANG Min, HU Liang, ZHOU Jin-song, and JING Juan-juan
Imaging spectropolarimeter (ISP) is a type of novel photoelectric sensor which integrated the functions of imaging, spectrometry and polarimetry. In the present paper, the concept of the ISP is introduced, and the advances in ISP at home and abroad in recent years is reviewed. The principles of ISPs based on novel deviImaging spectropolarimeter (ISP) is a type of novel photoelectric sensor which integrated the functions of imaging, spectrometry and polarimetry. In the present paper, the concept of the ISP is introduced, and the advances in ISP at home and abroad in recent years is reviewed. The principles of ISPs based on novel devices, such as acousto-optic tunable filter (AOTF) and liquid crystal tunable filter (LCTF), are illustrated. In addition, the principles of ISPs developed by adding polarized components to the dispersing-type imaging spectrometer, spatially modulated Fourier transform imaging spectrometer, and computer tomography imaging spectrometer are introduced. Moreover, the trends of ISP are discussed too..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1968 (2011)
Micro Hadamard Transform Near-Infrared Spectrometer
ZHANG Zhi-hai, MUO Xiang-xia, GUO Yuan-jun, and WANG Wei
A new type micro Hadamard transform (HT) near-infrared (NIR) spectrometer is proposed in the present paper. It has a MOEMS (Micro-Opto-Electro-Mechanical Systems) blazed grating HT mask. It has merits of compactness, agility of dynamic mask generation and high scan speed. The structure and theory of this spectrometer aA new type micro Hadamard transform (HT) near-infrared (NIR) spectrometer is proposed in the present paper. It has a MOEMS (Micro-Opto-Electro-Mechanical Systems) blazed grating HT mask. It has merits of compactness, agility of dynamic mask generation and high scan speed. The structure and theory of this spectrometer are analyzed. The 63-order Hadamard-S matrix and mask are designed. The mask is dynamically generated by program of MOEMS blazed gratings. The spectrum is in agreement with that measured by Shimadzu spectrometer in experiments. It has a wavelength range between 900 and 1 700 nm, spectral resolution of 19 nm, single scan time of 2.4 s, SNR of 44.67∶1, optical path of 70 mm×130 mm, and weight under 1 kg. It can meet the requirement of real time detection and portable application..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1975 (2011)
Study and Simulation of the Intensity Modulation-Fourier Transform Spectropolarimeter
WANG Xin-quan, XIANGLI Bin, HUANG Min, HU Liang, and JING Juan-juan
Intensity modulation-Fourier transform spectropolarimetry (IMFTSP) is a novel technology that combines the intensity modulation spectropolarimetry and Fourier transform spectroscopy. The IMFTSP can obtain full Stokes spectropolarimetric parameters simultaneously, and maintains the throughput (Jacquinot) and multiplex (Intensity modulation-Fourier transform spectropolarimetry (IMFTSP) is a novel technology that combines the intensity modulation spectropolarimetry and Fourier transform spectroscopy. The IMFTSP can obtain full Stokes spectropolarimetric parameters simultaneously, and maintains the throughput (Jacquinot) and multiplex (Fellgett) advantages. Yet aside from this, the IMFTSP has the advantage of reducing the complexity of data processing. The data collecting and spectropolarimetric parameters reconstruction processes were analyzed theoretically in this paper, the theoretical formulas are presented, and a whole process mathematical simulation for the IMFTSP system is introduced. The theory analysis and simulation results proved the feasibility of the IMFTSP..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1980 (2011)
Research on Photometric Calibration and Reflectance Calculation of CE-1 IIS Data
CHEN Chao, QIN Qi-ming, ZHANG Ning, WANG Jin-liang, LI Jun, and JIANG Hong-bo
The interference imaging spectrometer (IIS) is an important payload of the Chang’e-1 (CE-1) lunar satellite to achieve the distribution and content analysis of major elements and mineral types on the lunar surface. Due to the different observing conditions, the obtained lunar brightness varied significantly from place The interference imaging spectrometer (IIS) is an important payload of the Chang’e-1 (CE-1) lunar satellite to achieve the distribution and content analysis of major elements and mineral types on the lunar surface. Due to the different observing conditions, the obtained lunar brightness varied significantly from place to place. Thus, photometric calibration is required to eliminate the radiance difference caused by the different observing conditions. In the present paper, based on the analysis of IIS-2B data (after radiance calibration) of CE-1 satellite, we introduced the improved Lommel-Seeliger model to calibrate the IIS-2B radiance data pixel by pixel. Subsequently, an area adjacent to Apollo16 site was selected as the calibration target, and the bidirectional spectrum for soil sample 62231 was used as a calibration standard to obtain the reflectance from radiance data. Finally, soil sample 71501 was selected to take the accuracy evaluation on the reflectance results. Our work is useful for mineral identification and information extraction, as well as for the mapping of different minerals and rocks distribution on lunar surface..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1985 (2011)
Design and Analysis of a Depolarizer for the Space-Borne Grating Imaging Spectrometer
ZHAO Fa-cai, WANG Shu-rong, QU Yi, and LIN Guan-yu
The main portion of the space-borne grating imaging spectrometer-grating has intense polarization response. The objective of spectrometer is to measure the intensity accurately without bias as to the incident polarization state. One common method to overcome polarization bias in optical systems is the insertion of a deThe main portion of the space-borne grating imaging spectrometer-grating has intense polarization response. The objective of spectrometer is to measure the intensity accurately without bias as to the incident polarization state. One common method to overcome polarization bias in optical systems is the insertion of a depolarizer. The theory of horizontal-vertical (H-V) quartz depolarizer operation is described. A single H-V depolarizer was met the spectrometer polarization requirement according to its polarization character. Both the degree of depolarization and image degradation (especially the image doubling) were analyzed for the depolarizer design. The analysis results show that it satisfies the design requirements of the spectrometer, the polarization sensitivity is within the specification of 1% and the decrease in MTF due to the depolarizer is less than 1.5%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1991 (2011)
Research on Endmember Extraction Algorithm Based on Spectral Classification
GAO Xiao-hui, XIANGLI Bin, WEI Ru-yi, Lv Qun-bo, and WEI Jun-xia
Spectral unmixing is an important task for data processing of hyperspectral remote sensing, which is comprised of extracting the pure spectra (endmember) and calculating the abundance value of pure spectra. The most efficient endmember extracting algorithms (EEAs) is designed based on convexity geometry such as pure piSpectral unmixing is an important task for data processing of hyperspectral remote sensing, which is comprised of extracting the pure spectra (endmember) and calculating the abundance value of pure spectra. The most efficient endmember extracting algorithms (EEAs) is designed based on convexity geometry such as pure pixel index (PPI), N-finder algorithm (N-FINDR). Most EEAs choose pure spectra from all pixels of an image so that they have disadvantages like slow processing speed and poor precision. Partial algorithms need reducing the spectral dimension, which results in the difficulty in small target identification. This paper proposed an algorithm that classifies the hyperspetral image into some classes with homogeneous spectra and considers the mean spectra of a class as standard spectra for the class, then extracts pure spectrum from all standard spectra of classes. It reduces computation and the effect of system error, enhancing the speed and precision of endmember extraction. Using the least squares with constraints on spectral extraction and spectral unmixing, by controlling the band average value of the maximum spectral redundant allowance to control the number of endmembers, does not need to reduce the spectral dimension and predetermine the number of endmembers, so compared to N-finder algorithm, such algorithm is more rational..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1995 (2011)
The Characteristics of Multicolor Imaging System for Logarithmic Wavefront Coding
ZHANG Rong-fu, WANG Liang-liang, WANG Tao, LU Kang, LI Bin-yan, and ZHUANG Song-lin
The wavefront coding extension the depth of field (DOE) of an imaging system is by insert a phase plate into the pupil plane of a spatially incoherent imaging system, the encoded image can be digitally restored to produce a final image with improved depth dependent detail. To study the multicolor imaging performance ofThe wavefront coding extension the depth of field (DOE) of an imaging system is by insert a phase plate into the pupil plane of a spatially incoherent imaging system, the encoded image can be digitally restored to produce a final image with improved depth dependent detail. To study the multicolor imaging performance of a logarithmic wavefront coding system, the phase and chromatic aberration variation with wavelength are analyzed, and characteristics such as shape, distribution and width of two wavelengths’ PSF are compared. The research results show that if the chromatic aberration is excellently corrected then the technology can be used for multicolor even broadband spectrum DOE imaging system. Otherwise, the encode image can not be effectively decoded..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1999 (2011)
Extracting Buildings Height and Distribution Information in Tianjin City from the Shadows in ALOS Images
ZHANG Xiao-mei, HE Guo-jin, WANG Wei, JIAO Wei-li, and WANG Qin-jun
Spectral difference is an important aspect for extracting shadows of buildings. Based on the analysis of the relationship between the building heights and the shadows in ALOS Images, the paper presents the principle and the method for building heights estimation in a city from the shadows of an image, and works out a fSpectral difference is an important aspect for extracting shadows of buildings. Based on the analysis of the relationship between the building heights and the shadows in ALOS Images, the paper presents the principle and the method for building heights estimation in a city from the shadows of an image, and works out a feasible approach to determining shadow zones in a panchromatic ALOS Images. It has also contributed a standard process for extracting buildings distribution information of different heights in a city from the shadows in a panchromatic ALOS Images. A result with about 87.6% accuracy has been achieved while applying this technique to Tianjin City, which has demonstrated prospective applications of satellite remote sensing to urban purposes..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 2003 (2011)
A Dual-Wavelength Spectroscopic Method for the Low Chemical Oxygen Demand Determination
JIANG Ran, CHAI Xin-sheng, ZHANG Cui, and TANG Hong-liang
The present paper reports a dual wavelength spectroscopic method for the determination of chemical oxygen demand(COD) of low content samples, based on the absorption measurement at 440 and 560 nm. Since the absorptivities of Cr3+ at these two wavelengths are the same, a net absorption from dichromate ions can be determThe present paper reports a dual wavelength spectroscopic method for the determination of chemical oxygen demand(COD) of low content samples, based on the absorption measurement at 440 and 560 nm. Since the absorptivities of Cr3+ at these two wavelengths are the same, a net absorption from dichromate ions can be determined by subtracting the absorption at 560 nm(only contributed by Cr3+) from the absorption at 440 nm. The results showed that the detection limit of quantification is 8.6 mg·L-1 and the relative standard deviations are in the 2%～15% range for the low COD standard samples (≤100 mg·L-1) in this proposed method. Further more, the method does not require calibration based on the standard samples. The present method is simple, reliable, and accurate; it is suitable for the application in a mass testing for low COD samples..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 2007 (2011)
Simulated Annealing Based Phase Correction of Interferogram in Fourier Transform Imaging Spectrometer
HUANG Feng-zhen, YUAN Yan, ZHANG Xiu-bao, WANG Qian, and ZHOU Zhi-liang
Phase correction is one of the key technologies in the spectrum recovery of the Fourier transform imaging spectrometer. The present paper proposes a correction method based on simulated annealing algorithm to calculate phase error, which overcomes the disadvantage of the existing methods that can not correct the interfPhase correction is one of the key technologies in the spectrum recovery of the Fourier transform imaging spectrometer. The present paper proposes a correction method based on simulated annealing algorithm to calculate phase error, which overcomes the disadvantage of the existing methods that can not correct the interferogram with noise. The method determines the phase optimum solution by controlling the phase decrease function, attaining objective function value by correcting interferogram data with random phase value generated in the phase range, and determining the objective function increment in accordance with the Metropolis criterion. The simulation result of the algorithm indicates that the optimized phase error is less than 0.5%, and both the error accuracy and stability of the spectrum-recovered relative spectrum is less than 1%, which is a great improvement compared with the existing algorithm..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 2011 (2011)
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 31, Issue 7, 1 (2011)
© Copyright 2018-2021 | Chinese Laser Press. All Rights Reserved 沪ICP备15018463号-20