Journals >Spectroscopy and Spectral Analysis
Contents
2013
Volume: 33 Issue 7
60 Article(s)
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Research Article
Development of a Photoacoustic Spectroscopy System for the Measurement of Absorption Coefficient of Atmospheric Aerosols
LIU Qiang, NIU Ming-sheng, WANG Gui-shi, CAO Zhen-song, LIU Kun, CHEN Wei-dong, and GAO Xiao-ming
In the present paper, the authors focus on the effect of the resonance frequency shift due to the changes in temperature and humidity on the PA signal, present several methods to control the noise derived form gas flow and vibration from the sampling pump. Based on the efforts mentioned above, a detection limit of 1.4&In the present paper, the authors focus on the effect of the resonance frequency shift due to the changes in temperature and humidity on the PA signal, present several methods to control the noise derived form gas flow and vibration from the sampling pump. Based on the efforts mentioned above, a detection limit of 1.4×10-8 W·cm-1·Hz-1/2 was achieved for the measurement of atmospheric aerosols absorption coefficient. During the experiments, the PA cell was calibrated with the absorption of standard NO2 gas at 532 nm and the atmospheric aerosols were measured continuously. The measurement results show that the PAS is suitable for the real-time measurement of the absorption coefficient of atmospheric aerosols in their natural suspended state..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1729 (2013)
Spectroscopy Parameters of Ho3+ in Ho3+∶FOG and Ho3+∶FOV
YANG Xiao-dong, CHEN Ying, CHEN Xiao-bo, Sawarobori N, WANG Shui-feng, ZHOU Yong-fen, LI Song, XU Yi-zhuang, CHENG Huan-li, and YANG Guo-jian
In the present paper, the absorption spectra of Ho3+(0.5 mol%)-doped oxyfluoride glass (FOG) sample and Ho3+(0.5 mol%)-doped oxyfluoride vitroceramics (FOV) sample were measured through experiment. The authors calculated the intensity parameters Ω2, 4, 6 of the two materials according to J-O theory, and analyzed the poIn the present paper, the absorption spectra of Ho3+(0.5 mol%)-doped oxyfluoride glass (FOG) sample and Ho3+(0.5 mol%)-doped oxyfluoride vitroceramics (FOV) sample were measured through experiment. The authors calculated the intensity parameters Ω2, 4, 6 of the two materials according to J-O theory, and analyzed the possible reason for the difference between the two materials on the intensity parameters. After that the authors calculated oscillator strength, spontaneous radiative transition rate, branching ratio and integrated emission cross section and some other spectroscopic parameters of several excited states and then made a comparative analysis of the two materials based on these spectroscopic parameters. The authors found that the oscillator strength of trivalent holmium iron in FOV is about the same with the oscillator strength in YAlO3 and is similar to oscillator strength in FOG, while slightly larger than in that LBTAF and much larger than that in LaF3 and ZBLAN. By analyzing the calculated spectroscopic parameters, it can be found that some transitions, especially 5I7→5I8, 5F5→5I8 etc., have a relatively large oscillator strengths(larger than 10－6) and large integrated emission cross sections(larger than 10－18 cm). These transitions have the conditions to form laser passages, so they are worth a lot of attention. At last, application prospects of several strong luminescence transitions were concluded..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1734 (2013)
The Estimation of Cirrus Cloud Particulate Shape Using Combined Simulation and a Three-Wavelength Lidar Measurement
TAO Zong-ming, LIU Dong, WEI He-li, MA Xiao-min, SHI Bo, NIE Miao, ZHOU Jun, and WANG Ying-jian
The global occurrence of cirrus clouds can reach as high as 30%, whose scattering properties are essential impact on the climatic model, radiative transfer, and remote sensing. Their scattering properties are determined by the ice crystal shape, size distribution, refractive index and so on. Retrieval of the backscatteThe global occurrence of cirrus clouds can reach as high as 30%, whose scattering properties are essential impact on the climatic model, radiative transfer, and remote sensing. Their scattering properties are determined by the ice crystal shape, size distribution, refractive index and so on. Retrieval of the backscattering color ratios of cirrus cloud using a 355, 532 and 1 064 nm three-wavelength lidar, combined with the simulation of the three backscattering color ratios of different ice crystal shape, the shape of the lidar-measured ice crystal can be estimated. The results indicate that the shape of cirrus cloud over Hefei city is mostly composed by aggregates..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1739 (2013)
Effect of Ionic Liquid ［bmim］［PF6］ on the Transient Photolysis Behavior of Xanthone
FU Hai-ying, CAO Xi-yan, XING Zhao-guo, and WU Guo-zhong
The transient photochemical behavior of xanthone(XAN) in 1-butyl-3-methyl imidazolium hexafluoride phosphate ionic liquid (［bmim］［PF6］) or binary mixed solution with acetonitrile (MeCN) was investigated by nano-second laser photolysis techniques. The spectral blue shift of 3XAN* was observed in the neat ［bmim］［PF6］ or The transient photochemical behavior of xanthone(XAN) in 1-butyl-3-methyl imidazolium hexafluoride phosphate ionic liquid (［bmim］［PF6］) or binary mixed solution with acetonitrile (MeCN) was investigated by nano-second laser photolysis techniques. The spectral blue shift of 3XAN* was observed in the neat ［bmim］［PF6］ or IL/MeCN mixture solution compared to MeCN solution. And the yield was also increased. Moreover, the energy transfer rate constant of XAN and naphthalene (NAP) was affected by the concentrations of ionic liquid. The values decreased rapidly with increasing VIL. For example, the values were 1.2×1010 mol·L-1·s-1 in MeCN, and 1.1×108 mol·L-1·s-1 in ［bmim］［PF6］, respectively. The photo-induced electron transfer between XAN and N,N-dimethylaniline was also investigated by changing the concentrations of ［bmim］［PF6］ in binary solution..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1744 (2013)
Characterization of Thermal Denaturation Process of Proteinase K by Spectrometry
ZHANG Qi-bing, NA Xin-zhu, and YIN Zong-ning
The effect of different temperatures on the activity and conformational changes of proteinase K was studied. Methods Proteinase K was treated with different temperatures, then denatured natural substrate casein was used to assay enzyme activity, steady-state and time-resolved fluorescence spectroscopy was used to studyThe effect of different temperatures on the activity and conformational changes of proteinase K was studied. Methods Proteinase K was treated with different temperatures, then denatured natural substrate casein was used to assay enzyme activity, steady-state and time-resolved fluorescence spectroscopy was used to study tertiary structure, and circular dichroism was used to study secondary structure. Results show with the temperature rising from 25 to 65 ℃, the enzyme activity and half-life of proteinase K dropped, maximum emission wavelength red shifted from 335 to 354 nm with fluorescence intensity decreasing. Synchronous fluorescence intensity of tryptophan residues decreased and that of tyrosine residues increased. Fluorescence lifetime of tryptophan residues reduced from 4.427 1 to 4.032 4 ns and the fraction of α-helix dropped. It was concluded that it is simple and accurate to use steady-state/time-resolved fluorescence spectroscopy and circular dichroism to investigate thermal stability of proteinase K. Thermal denaturation of proteinase K followed a three-state process. Fluorescence intensity of proteinase K was affected by fluorescence resonance energy transfer from tyrosine to tryptophan residues. The α-helix was the main structure to maintain conformational stability of enzyme active site of proteinase K..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1749 (2013)
Vibrational Temperature of Plasma Plume in Atmospheric Pressure Air
LI Xue-chen, CHANG Yuan-yuan, JIA Peng-ying, ZHAO Huan-huan, and BAO Wen-ting
A tri-electrode discharge device was designed in a dielectric barrier discharge configurations to generate a fairly large volume plasma plume in atmospheric pressure air. The discharge characteristics of the plasma plume were investigated by an optical method. The discharge emission from the plasma plume was collected A tri-electrode discharge device was designed in a dielectric barrier discharge configurations to generate a fairly large volume plasma plume in atmospheric pressure air. The discharge characteristics of the plasma plume were investigated by an optical method. The discharge emission from the plasma plume was collected by a photomultiplier tube. It was found that the number of discharge pulse per cycle of the applied voltage increased with increasing the peak value of the applied voltage. The emission spectra of the plasma plume were collected by a spectrometer. The vibrational temperature was calculated by fitting the experimental data to the theoretical one. Results showed that the vibrational temperature of the plasma plume decreases with increasing the Up. Spatially resolved measurement of the vibrational temperature was also conducted on the plasma plume with the same method. Results showed that the vibrational temperature increases firstly and then decreases with increasing distance from the nozzle. The vibrational temperature reachs its maximum when the distance is 5.4 mm from the nozzle. These experimental phenomena were analyzed qualitatively based on the discharge theory. These results have important significance for the industrial applications of the plasma plume in atmospheric pressure air..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1754 (2013)
Influence of Bi3+ Doping on Properties of CaMoO4∶Eu3+ Phosphors
ZHANG Qing-xia, LONG Dan-dan, ZHANG Fan, QI Xiao-hua, ZHANG Heng, YAN Jing-hui, and ZOU Ming-qiang
Europium doped CaMoO4 and bismuth co-doped CaMoO4∶Eu3+ phosphors were prepared via microemulsion-hydrothermal method. The structure, morphology and luminescence properties of samples were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and fluorescence spectroscopy, respectively. The XRD patteEuropium doped CaMoO4 and bismuth co-doped CaMoO4∶Eu3+ phosphors were prepared via microemulsion-hydrothermal method. The structure, morphology and luminescence properties of samples were investigated by X-ray diffraction(XRD), scanning electron microscopy(SEM) and fluorescence spectroscopy, respectively. The XRD patterns of as-prepared samples were in agreement with the PDF # 29-0351 of CaMoO4, which indicated that the phosphor possessed tetragonal crystal structure. SEM images showed that the samples were basically flake in shape and their average size was 1.5~2.5 μm. The critical molar concentration of activator (Eu3+) in CaMoO4∶Eu3+ was 5%, and the predominant peak of CaMoO4∶Eu3+ located at 616 nm, corresponding to the 5D0→7F2 electronic dipole transition of Eu3+. The photoluminescence color can be tuned from orange-yellow (0.514, 0.537) to white (0.339, 0.333) by adjusting the doping concentrations of Eu3+ ions. To enhance the red emission intensity of Eu3+, Bi3+ was used to co-dope CaMoO4∶Eu3+ as sensitizers. When the concentration of Bi3+ is 3%, luminescence intensity was maximum. The chromaticity coordinates (CIE) varied from orange (0.497, 0.347) to red (0.585, 0.349) with increasing the content of Bi3+..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1758 (2013)
Properties of Phosphorescent Organic Light-Emitting Diodes with Different Doping Order on Light Emitting Layer
ZHANG Wei, ZHANG Fang-hui, and HUANG Jin
Utilizing GIr1(green) and R-4B(red) phosphorescent dye, organic light-emitting diodes with different doping orders on red and green light-emitting layers were fabricated. The authors investigated the luminescent properties of devices combined with the effect of electron (TCTA) and hole (BCP) blocking layer. The resultsUtilizing GIr1(green) and R-4B(red) phosphorescent dye, organic light-emitting diodes with different doping orders on red and green light-emitting layers were fabricated. The authors investigated the luminescent properties of devices combined with the effect of electron (TCTA) and hole (BCP) blocking layer. The results showed that the great impacts on spectrum, light efficiency, luminance and luminescent color were produced based on different doping order, and the authros also found the strong emission peak at the interface of the BCP and CBP layer. With the use of the red and green doping type, 0.527 mA·cm-2, 104 cd·m-2, 19.75 cd·A-1 and （0.371 7, 0.576 8） could be reached, respectively. The reasons were that on the one hand, because of large difference between energy levels of host material CBP and doping material GIr1, R-4B, and charge trapping and hopping via dopants were the main mechanism of change; on the other hand, for the different energy levels between dopants and blocking layers, the doping sequence could affect barrier distribution, and then affect the electric field distribution..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1763 (2013)
Influence of BCP on Efficiency of Red Phosphorescent Electroluminescent Device
HUANG Jin, and ZHANG Fang-hui
The present paper uses the R-4B as phosphor dopant, the main body was CBP, regulation carrier composite layer was BCP, and the device structure was ITO/MoO3 (30)/NPB (40)/TCTA (10)/CBP∶R-4B(6%)(15)/BCP(x)/CBP∶R-4B(6%)(15)/BCP(10)/Alq3(40)/LiF/Al. In the device, x was the thickness of the BCP with five different thickneThe present paper uses the R-4B as phosphor dopant, the main body was CBP, regulation carrier composite layer was BCP, and the device structure was ITO/MoO3 (30)/NPB (40)/TCTA (10)/CBP∶R-4B(6%)(15)/BCP(x)/CBP∶R-4B(6%)(15)/BCP(10)/Alq3(40)/LiF/Al. In the device, x was the thickness of the BCP with five different thickness of the device. At the same time, another contrast device was made, which had been optimized at MoO3 without regulated BCP layer. The result shows that the luminous area was 1.18 cm2, BCP was 4, MoO3 was 30 nm, its performance was the best, light voltage was 4 V, maximum efficiency was 18.9 cd·A-1, its corresponding EL main peak was at 612 nm, and color coordinates was (0.643, 0.353), getting stable and high efficient red phosphor OLED devices..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1767 (2013)
Optical Properties Research of NH4NO3 by Fourier Transform Infrared Spectroscopy
LIU Na, WEI Xiu-li, GAO Min-guang, XU Liang, TONG Jing-jing, LI Xiang-xian, and JIN Ling
In the present paper, the infrared spectrum of aerosol and NH4NO3 was analysed and compared, and the result showed that the infrared spectral features of aerosol are consistent with that of NH4NO3. The absorption coefficient α and the mass absorption cross section κ of NO-3 was calculated by the transmissivity of NO-3 In the present paper, the infrared spectrum of aerosol and NH4NO3 was analysed and compared, and the result showed that the infrared spectral features of aerosol are consistent with that of NH4NO3. The absorption coefficient α and the mass absorption cross section κ of NO-3 was calculated by the transmissivity of NO-3 in NH4NO3 according to Beer-Lambert law. Then the imaginary part of the complex refractive index was calculated through α. The real part of the complex refractive index was derived from the K-K（Kramers-Kroning）relationship. It has important significance for further research on the scattering and absorption characteristics of the different composition of the atmospheric aerosol through analysing the results of the experiment..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1771 (2013)
Study on Soil Carbon Estimation by On-the-Go Near-Infrared Spectra and Partial Least Squares Regression with Variable Selection
SHEN Zhang-quan, LU Bi-hui, SHAN Ying-jie, and XU Hong-wei
The present paper tried to evaluate the effectiveness and improvement of variable selection before modeling with partial least squares regression (PLSR). Based on the independent test dataset, and compared with the PLSR model derived from all spectral variables, the prediction accuracy by modeling after variable selectThe present paper tried to evaluate the effectiveness and improvement of variable selection before modeling with partial least squares regression (PLSR). Based on the independent test dataset, and compared with the PLSR model derived from all spectral variables, the prediction accuracy by modeling after variable selection has been improved. Thus, the results showed that variable selection was beneficial and necessary for soil carbon modeling by on-the-go NIRS. UVE (uninformative variable elimination) and UVE-SPA (successive projection algorithm) could perform effective variable selection and created promising models, and SPA and GA-PLS (genetic algorithm PLS) failed to make appropriate models. For synergy interval PLS (siPLS), change in interval number and number of interval for modeling could affect the prediction accuracy obviously. Promising models could be made by selecting appropriate interval number and number of interval for modeling, and siPLS could achieve similar prediction accuracy to UVE or UVE-SPA, and the shortcoming was that siPLS required a lot of computing time to find optimal combination of intervals for modeling..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1775 (2013)
Influence of Measurement Errors of Radiation in NIR Bands on Water Atmospheric Correction
XU Hua, LI Zheng-qiang, YIN Qiu, and GU Xing-fa
For standard algorithm of atmospheric correction of water, the ratio of two near-infrared (NIR) channels is selected to determine an aerosol model, and then aerosol radiation at every wavelength is accordingly estimated by extrapolation. The uncertainty of radiation measurement in NIR bands will play important part in For standard algorithm of atmospheric correction of water, the ratio of two near-infrared (NIR) channels is selected to determine an aerosol model, and then aerosol radiation at every wavelength is accordingly estimated by extrapolation. The uncertainty of radiation measurement in NIR bands will play important part in the accuracy of water-leaving reflectance. In the present research, erroneous expressions were derived mathematically in order to see the error propagation from NIR bands. The errors distribution of water-leaving reflectance was thoroughly studied. The results show that the bigger the errors of measurement are made, the bigger the errors of water-leaving reflectance are retrieved, with sometimes the NIR band errors canceling out. Moreover, the higher the values of aerosol optical depth or the more the component of small particles in aerosol, the bigger the errors that appear during retrieval..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1781 (2013)
Effect of the Near Infrared Spectrum Resolution on the Nitrogen Content Model in Green Tea
YANG Dan, LIU Xin, LIU Hong-gang, ZHANG Ying-bin, and YIN Peng
The effect of different resolutions(2, 4, 6, 8, 16 cm-1) on the near infrared spectrogram and nitrogen content model for green tea was studied. Test results showed that instrument resolution could influence the spectra quality. The higher the resolution was, the richer the information would be, but the noise would incrThe effect of different resolutions(2, 4, 6, 8, 16 cm-1) on the near infrared spectrogram and nitrogen content model for green tea was studied. Test results showed that instrument resolution could influence the spectra quality. The higher the resolution was, the richer the information would be, but the noise would increase. With lower resolution, spectrogram would be much more smooth, but get seriously distorted, and prediction accuracy would decrease at the same time. The partial least squares model was built after spectral pretreatment. When resolution was 4 cm-1, the RMSEP value of external validation set was 0.054 6, which was obviously lower than others. The Corr.Coeff. was 0.998 2. Its prediction performance was the best and the prediction accuracy better. STDEV and RSD were 0.020 and 0.334 respectively. Resolution 4 cm-1 for near infrared spectrometer collecting green tea samples was the optimal resolution. This research can provide a reference for parameters selection when collecting green tea spectra with near infrared spectrometer, improve the stability and prediction performance of the model and promote the application and promotion of the near infrared spectroscopy for tea..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1786 (2013)
The Research on the Identification of Some Polygonatum Crude Drugs by Fourier Transform Infrared Spectrometry
ZHOU Ye, LI Pei-fu, ZHANG Qing-wei, ZHANG Gong, HE Li-lin, and ZHANG Bo-li
The common peak ratio and variant peak ratio were calculated by FTIR spectroscopy of six medicinal plants of polygonatum. The index sequence of common peak ratio and variant peak ratio of six medicinal plants was established and the FTIR spectroscopy was analyzed by cluster analysis, which indicated the sibship of the The common peak ratio and variant peak ratio were calculated by FTIR spectroscopy of six medicinal plants of polygonatum. The index sequence of common peak ratio and variant peak ratio of six medicinal plants was established and the FTIR spectroscopy was analyzed by cluster analysis, which indicated the sibship of the six medicinal plants. polygonati rhizoma, polygonati odorati rhizoma and their adulterant such as Polygonatum filipes Merr., Polygonatum macropodium Turcz. and Polygonatum humile Fisch Ex Maxim. could be identified by comparing second derivative spectrum of the samples. FTIR with good characteristics such as simple and rapid procedures, nondestructive testing, small amount of sample required, good reproducibility and specificity of fingerprint, provides a new method for identification of polygonati rhizoma, polygonati odorati rhizoma and their adulterant..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1791 (2013)
Miniature Near-Infrared Fibre Optic Spectrometer for the Quantitative Detection of Protein and Fat in Milk Powder
ZHANG Zhong-wei, WEN Zhi-yu, ZENG Tian-ling, WEI Kang-lin, and LIANG Yu-qian
The method based on miniature near-infrared spectrometer combined with Y fiber optic probe to detect the protein and fat in milk powder by diffuse reflectance spectroscopy in the wavelength range of 900～1 700 nm was proposed. By selecting the appropriate spectral bands, the correction models of protein and fat were estThe method based on miniature near-infrared spectrometer combined with Y fiber optic probe to detect the protein and fat in milk powder by diffuse reflectance spectroscopy in the wavelength range of 900～1 700 nm was proposed. By selecting the appropriate spectral bands, the correction models of protein and fat were established with partial least squares algorithm using Unscrambler 9.7 Chemometrics software. The determination coefficients R2 of the correction modes are 0.987 and 0.986 for protein and fat respectively, and the root mean square errors RMSEC are 0.385 and 0.419 respectively. Using these correction models to predict the protein and fat contents with 30 sets of forecast sample data, the prediction standard deviation is SEPProtein=0.751 for protein, and is SEPFat=1.109 for fat. The results indicate that these correction models have prediction capability with unknown samples and meet the on line requirements..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1796 (2013)
Determination of Chlorogenic Acid, Rutin, Scopoletin and Total Polyphenol in Tobacco by Fourier Transform Near Infrared Spectroscopy
LENG Hong-qiong, GUO Ya-dong, LIU Wei, ZHANG Tao, DENG Liang, and SHEN Zhi-qiang
The objective of the present study was to investigate the feasibility of predicting chlorogenic acid, rutin, scopoletin and total polyphenol in tobacco by Fourier transform near-infrared (FT-NIR) spectroscopy. The partial least squares(PLS) regression method, second derivative and Norris derivative filter were applied The objective of the present study was to investigate the feasibility of predicting chlorogenic acid, rutin, scopoletin and total polyphenol in tobacco by Fourier transform near-infrared (FT-NIR) spectroscopy. The partial least squares(PLS) regression method, second derivative and Norris derivative filter were applied in the NIR spectroscopy prediction of chlorogenic acid, rutin, scopoletin and total polyphenol in the range of 7 500 to 4 000 cm-1. For chlorogenic acid, rutin, scopoletin and total polyphenol, the determination coefficients were 0.976 6, 0.941 9, 0.957 1 and 0.966 6, respectively. The SEP/SEC values for them were <1.2, and the SD/SEP values for them were >2. The root mean square error of cross validation (RMSECV) of the four calibration models were 1.938 9, 1.046 2, 0.047 9 and 2.745 2, respectively. NIR spectroscopy was compared with the conventional methods. The results show that the two methods showed no significant difference at the significant level of 0.05. NIR spectroscopy technology can accurately analyze chlorogenic acid, rutin, scopoletin and total polyphenol in tobacco..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1801 (2013)
Quantization Determination Study of Micro-Raman Spectroscopy of Methemoglobin Induced by Sodium Nitrite
GUO Shi-jun, ZENG Chang-chun, LI Li-jun, NIE Guang, and LIU Song-hao
In the present study, Raman spectral characteristics of methemoglobin (MetHb) induced by sodium nitrite (NaNO2) were investigated. Hemoglobin (Hb) was oxidated to MetHb with NaNO2, the Raman spectral specific changes of MetHb was studied by determining the Raman spectral changes of methemoglobin/total hemoglobin of difIn the present study, Raman spectral characteristics of methemoglobin (MetHb) induced by sodium nitrite (NaNO2) were investigated. Hemoglobin (Hb) was oxidated to MetHb with NaNO2, the Raman spectral specific changes of MetHb was studied by determining the Raman spectral changes of methemoglobin/total hemoglobin of different ratios, and the Raman intensities of methemoglobin/total hemoglobin of different ratios at 1 586, 1 605 and 1 637 cm-1 were linearly fitted to realize its quantitative detection. The results show that the completely oxidized MetHb can be obtained when the molar ratio of NaNO2 to Hb is 3.5∶1 whose Raman characteristic peaks are at around 499, 1 340, 1 562 and 1 622 cm-1, and that the linear fitting correlation coefficients R2 of the Raman intensities of methemoglobin/total hemoglobin of different ratios at 1 586, 1 605 and 1 637 cm-1 are 0.972 84, 0.997 97 and 0.991 26 respectively, which shows a good linear relationship. This study indicates that the Raman spectrums of MetHb induced by NaNO2 have characteristic differences when compared with normal Hb, that the locations and intensities of Raman characteristic peaks change correspondingly with the alterations of the ratios of methemoglobin/total hemoglobin, and that there are linear correlations between the ratios and their corresponding Raman intensities, which would provide theoretical bases for the clinical Raman spectral detection and quantitative study of methemoglobinemia..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1805 (2013)
Application of Polarized Raman Spectroscopy in the Research on Molecule Conformation
ZHANG Yu-feng, GONG Yan, QIAO Bao-hua, FENG Tian-li, and WANG Wen-qing
In the present paper, the carbon tetrachloride (CCl4) is the main object of study. According to the calculation of the degree of depolarization, the authors can understand CCl4 crystal vibration. With the comparison between the calculated theoretical value and the experimental value, we are sure that our work is accuraIn the present paper, the carbon tetrachloride (CCl4) is the main object of study. According to the calculation of the degree of depolarization, the authors can understand CCl4 crystal vibration. With the comparison between the calculated theoretical value and the experimental value, we are sure that our work is accurate..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1810 (2013)
Green Synthesis of Silver Nanoparticles and Their Application in SERS
YANG Bi-wen, GUO Zhou-yi, LIU Zhi-ming, WAN Ming-ming, QIN Xiao-chu, and ZHONG Hui-qing
In the present paper, we have successfully synthesized silver nancomparticles by reducing of silver nitrate in alkaline solution via 60 ℃ water bath for 20 minutes with the use of tyrosine, a nontoxic and green macromolecule, as a reducing and stabilizing agent. The formation of silver nanoparticles was observed visualIn the present paper, we have successfully synthesized silver nancomparticles by reducing of silver nitrate in alkaline solution via 60 ℃ water bath for 20 minutes with the use of tyrosine, a nontoxic and green macromolecule, as a reducing and stabilizing agent. The formation of silver nanoparticles was observed visually by color change of the solutions (from faint yellow to brown yellow). The morphologies of the Ag NPs were characterized by UV-Vis absorption spectroscopy and transmission electron microscopy (TEM). The UV-Vis absorption peak of silver nanoparticles located at 412 nm. The TEM image of silver nanoparticles indicated that the diameters of nanospheres are mainly in the range 15～25 nm. In order to evaluate the SERS activity of the silver nancomparticles, crystal violet and folic acid were used as the Raman probe molecule. The experimental results indicated that there are two ascendancies, firstly, the approach is convenient and the reaction condition is facile, secondly, tyrosine is a water-soluble, nontoxic and biodegradable macromolecule, which makes this approach provide a green strategy to prepare Ag NPs. Significantly, the synthesized Ag NPs exhibits good surface enhanced Raman scattering (SERS) activity as SERS substrates to detect crystal violet and folic acid in aqueous solution..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1816 (2013)
Effect of Straw Incorporation on Three-Dimensional Fluorescence Spectrum of Dissolved Organic Matter in Arid Loess
FAN Chun-hui, ZHANG Ying-chao, HE Lei, and WANG Jia-hong
The three-dimensional fluorescence spectrum was used to investigate the fluorescence characterization of dissolved organic matter (DOM) before and after straw incorporation in arid loess, and the variation of humification degree and Pb(Ⅱ) speciation were illustrated. The results showed that the fluorescence peaks of loThe three-dimensional fluorescence spectrum was used to investigate the fluorescence characterization of dissolved organic matter (DOM) before and after straw incorporation in arid loess, and the variation of humification degree and Pb(Ⅱ) speciation were illustrated. The results showed that the fluorescence peaks of loess appears at the regions of λex/em=240～270/280～340 and λex/em=325/450, referred as UV fulvic-like fluorescence, and visible fulvic-like and humic-like fluorescence, respectively. After straw incorporation for 60 days, the intensity of UV fulvic-like fluorescence peaks increases, and novel humic-like fluorescence peaks appears around the region of λex/em=250/440 and λex/em=320～350/350～400. The longer time of straw incorporation would accelerate the humification degree of loess and decrease the bioactivity of Pb(Ⅱ). The three-dimensional fluorescence spectrum is appropriate for characterization identification of DOM in arid loess before and after straw incorporation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1820 (2013)
Studies on Fluorescence Spectral Characteristics of Fulvic Acid (FA) from Xingkai Lake Sediments
ZHAO Jin, XI Bei-dou, XU Qi-gong, ZHAO Yue, WEI Zi-min, XU Jin-long, and ZHAO Xin-yu
Four samples (sample No. HXXD, HXXX, HXDX and HXDB) were taken from Xingkai Lake Sediments in Heilongjiang province and fluorescence spectral characteristics of Fulvic acid (FA) from sediments were studied. Conventional and excitation-emission matrix (EEM) all indicated that FA from HXXD sediment exhibited primary peakFour samples (sample No. HXXD, HXXX, HXDX and HXDB) were taken from Xingkai Lake Sediments in Heilongjiang province and fluorescence spectral characteristics of Fulvic acid (FA) from sediments were studied. Conventional and excitation-emission matrix (EEM) all indicated that FA from HXXD sediment exhibited primary peaks at longer wavelengths. The analysis of fluorescence characteristic parameters indicated that the degree of humification of FA from all sample points were in the order: HXXD>HXDX>HXDB>HXXX. Fluorescence index (f450/500) suggested that FA from HXXD mainly originated from terrestrial sources, while the FA from other samples mainly originated from aquatic organism sources and terrestrial sources. Based on EEM fluorescence regional integration (FIR), the percent fluorescence responses (Pi, n) of five regions in 3EEMs was calculated. The distributions of PⅤ, n (humic acid-like region) and PⅢ, n (fulvic acid-like region) were the largest in all samples. The conclusion of the degree of humification of FA based on FIR was consistent with the analysis of conventional fluorescence parameters. The correlation analysis showed that, r(A, C) was significantly correlative with PⅤ, n/PⅢ, n, (PⅤ, n+PⅢ, n)/(PⅠ, n+PⅡ, n+PⅢ, n) and PⅤ, n. The results suggest that r(A, C) index is a reasonable tool for assessing humification degree of FA from Xingkai Lake sediments..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1824 (2013)
Effect of REE on Growth of Bacteria and Fluorescence spectrum of DNA
CHAI Rui-juan, and WANG Yu-liang
Growth curve of bacteria treated by the rare earth elements and calmodulin inhibitor (chlorpromazine) was studied, and the effect of REE on calf thymus-DNA and intracellular DNA in bacteria was studied by fluorescence spectrum. The results showed that the logarithmic phase of growth and fission of bacteria can be advanGrowth curve of bacteria treated by the rare earth elements and calmodulin inhibitor (chlorpromazine) was studied, and the effect of REE on calf thymus-DNA and intracellular DNA in bacteria was studied by fluorescence spectrum. The results showed that the logarithmic phase of growth and fission of bacteria can be advanced by REE, so they grew faster than contrast. At the same time, Bacillus subtilis was found bigger by SEM. But growth and fission was inhibited by chlorpromazine, indicating that the mechanism about growth and fission of bacteria by REE was connected with calmodulin inhibitor. Fluorescence of ct-DNA can be enhanced by REE. But intracellular DNA in bacteria was different, it can be enhanced by Ce(NO3)3, quenched by La(NO3)3. so we think that the function of REE to biological materials was very complicated..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1829 (2013)
A Method for Measuring Emission Spectrum of YAG Phosphor Used in LED White Light under Practical Conditions
XU Yan-fang, ZHANG Guo-sheng, LI Lu-hai, and DING Ying-kun
A new method for measuring the emission spectra of the YAG phosphor under blue light excitation was proposed. Utilizing the Gaussian function and Fermi function fitting and simulated annealing optimization techniques, mathematical fitting functions for matching mixed emission spectrum were obtained. And so, the emissioA new method for measuring the emission spectra of the YAG phosphor under blue light excitation was proposed. Utilizing the Gaussian function and Fermi function fitting and simulated annealing optimization techniques, mathematical fitting functions for matching mixed emission spectrum were obtained. And so, the emission spectrum of the YAG phosphor was separated, further its luminescence properties can be characterized. Our experiment results proved that its characteristic parameters present non-negligible differences. The optical metric differences such as those in quantum efficiency, light emitting efficiency and energy efficiency are higher than 1%. The difference in CCT (correlated color temperature) is up to tens of K, and chromaticity indicators also produce differences in chromaticity coordinates, dominant wavelength and color purity. But little change is there in the half-peak bandwidth, and peak wavelength is basically unaffected. All these show that the established method can improve the measurement accuracy of YAG yellow phosphor emission spectrum under practical conditions..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1834 (2013)
Water Quality Analysis by UV-Vis Spectroscopy: A Review of Methodology and Application
HOU Di-bo, ZHANG Jian, CHEN Lin, HUANG Ping-jie, and ZHANG Guang-xin
Compared with the traditional approaches, UV-Vis spectroscopy is gaining growing acceptance in the field of online water-quality monitoring as an effective method for water quality analysis. UV-Vis spectroscopy has the advantages of fast response, low maintenance costs, and no secondary pollution. In the present paper,Compared with the traditional approaches, UV-Vis spectroscopy is gaining growing acceptance in the field of online water-quality monitoring as an effective method for water quality analysis. UV-Vis spectroscopy has the advantages of fast response, low maintenance costs, and no secondary pollution. In the present paper, the principle of water quality analysis by UV-Vis spectroscopy is introduced. Existing researches on the online analysis of water quality using UV-Vis spectrum and data fusion technologies are comprehensively reviewed. The applications of UV-Vis based methods in multi-parameter water-quality monitoring, water-quality classification, and water-quality alarm are also discussed. Finally, future research directions are outlined..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1839 (2013)
Quantitative Analysis of Protein Concentration by Absorption Peak Integration Method of UV Spectroscopy—Taking Alkaline Phosphatase as an Example
ZHU Yuan-rong, WU Feng-chang, and LIN Ying
Adsorption of alkaline phosphatase (APase) on minerals (goethite, montmorillonite) and sediments from Taihu Lake was studied. However, the concentration of alkaline phosphatase in the supernatant cannot be analyzed by the adsorption at 280 nm due to that the UV spectroscopy was changed. Quantitative analysis of alkalinAdsorption of alkaline phosphatase (APase) on minerals (goethite, montmorillonite) and sediments from Taihu Lake was studied. However, the concentration of alkaline phosphatase in the supernatant cannot be analyzed by the adsorption at 280 nm due to that the UV spectroscopy was changed. Quantitative analysis of alkaline phosphatase in the supernatant by the absorption peak (252~305 nm) integration method of UV spectroscopy was developed. This method determined the concentrations of alkaline phosphatase well. Compared to the results of Bradford, the absorption peak integration method can determine the concentrations of supernatant fast, conveniently, and accurately. This method can also be applied to other protein solution analysis and similar experiments. The drawbacks of traditional single wavelength method (280nm) were overcome to some extent based on the method of absorption peak integration..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1845 (2013)
Study on the UV-Quantitative Analysis of Theabrownins in Pu-Erh Tea
YANG Yan, PENG Chun-xiu, LIU Hua-rong, SHENG Jun, and GONG Jia-shun
An UV-quantitative analysis method for the theabrownin (TB) in Pu-erh tea and its derived products was established in the present study. The results showed that the Pu-erh tea shows characteristic absorption at the wavelength of 270 nm, which can be used as wavelength for the content determination of TB. The preparatioAn UV-quantitative analysis method for the theabrownin (TB) in Pu-erh tea and its derived products was established in the present study. The results showed that the Pu-erh tea shows characteristic absorption at the wavelength of 270 nm, which can be used as wavelength for the content determination of TB. The preparation methods of standard TB and standard curve were also established. The determination results show that the method is simple, the results have certain credibility, and the established method can be used for the determination of TB in Pu-erh tea and its derived products..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1850 (2013)
Modeling Continuous Scaling of NDVI Based on Fractal Theory
LUAN Hai-jun, TIAN Qing-jiu, YU Tao, HU Xin-li, HUANG Yan, DU Ling-tong, ZHAO Li-min, WEI Xi, HAN Jie, ZHANG Zhou-wei, and LI Shao-peng
Scale effect was one of the very important scientific problems of remote sensing. The scale effect of quantitative remote sensing can be used to study retrievals’ relationship between different-resolution images, and its research became an effective way to confront the challenges, such as validation of quantitative remScale effect was one of the very important scientific problems of remote sensing. The scale effect of quantitative remote sensing can be used to study retrievals’ relationship between different-resolution images, and its research became an effective way to confront the challenges, such as validation of quantitative remote sensing products et al. Traditional up-scaling methods cannot describe scale changing features of retrievals on entire series of scales; meanwhile, they are faced with serious parameters correction issues because of imaging parameters’ variation of different sensors, such as geometrical correction, spectral correction, etc. Utilizing single sensor image, fractal methodology was utilized to solve these problems. Taking NDVI(computed by land surface radiance) as example and based on Enhanced Thematic Mapper Plus (ETM+) image, a scheme was proposed to model continuous scaling of retrievals. Then the experimental results indicated that: (a) For NDVI, scale effect existed, and it could be described by fractal model of continuous scaling; (2) The fractal method was suitable for validation of NDVI. All of these proved that fractal was an effective methodology of studying scaling of quantitative remote sensing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1857 (2013)
Noninvasive Medical Imaging System for Tissue Classification Using RGB LED and Micro-Spectroscopy
YANG Bor-wen, LIN Yu-min, WANG Shih-yuan, and YING Shang-ping
As skin is the exterior organ of human body, cosmetic industry advances year by year. To reveal the details of skin tissue, three-dimensional medical imaging is required. Based on the idea of “readout instead of write”, a new scheme named spectral classification imaging (SCI) is proposed in the present study to reduce As skin is the exterior organ of human body, cosmetic industry advances year by year. To reveal the details of skin tissue, three-dimensional medical imaging is required. Based on the idea of “readout instead of write”, a new scheme named spectral classification imaging (SCI) is proposed in the present study to reduce the invasiveness by applying the reflection spectra of the sample points for three-dimensional medical imaging. Broad-band light source and the spectrometer were employed to collect the spectra curves of scanned region, which were classified into several tissue types by their cross-correlations. A colorful tissue tomography can finally be obtained by filling in each image pixel the color indicating the corresponding tissue type. The lateral/longitudinal resolutions and penetration depth were analyzed to characterize the SCI system. The lateral resolution is based on the source’s diffraction limit, the longitudinal resolution is by its depth-of-focus, and the penetration depth is equivalent to its skin depth. The imaging results of an amethyst of 0.6 mm (x-direction)×0.6 mm (y-direction) with a total of 120×120 pixels per frame and a guppy fish of 3.2 mm (x-direction)×2.4 mm (y-direction) of 160×120 pixels, are presented to show the image quality. The effects of the cross-correlation coefficient and the number of source wavelengths on the imaging results were explored. The value of cross-correlation threshold determines the required time for imaging, the resulted number of tissue groups, and the variety of tissue colors in the imaging result. Owing to its virtual noninvasiveness and easy configuration, the SCI system is highly promising for practical uses. RGB LEDs possess merits of broad bandwidth, low cost, long lifetime, small volume, and are ready to be integrated into a multi-color source module. Replacing the wide-band light source and the spectrometer module with a composite RGB LED with discrete wavelengths and a micro-spectrometer for spectra retrieval, the system has great potential to be minimized as a hand-held product for noninvasive medical imaging. It leads to reduced use of non-eco-friendly cosmetics and extended advance of cosmetic dermatology..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1863 (2013)
Theoretical Research on a High Q Factor Elliptical Differential Photoacoustic Resonator
TANG Xi-yao, YANG Yuan-hong, and YANG Ming-wei
The sensitivity of photoacoustic (PA) sensors strongly depends on the characteristic of PA cell. In the present paper, a novel elliptical differential PA cell was proposed to enhance the signal noise ratio of PA system. An acoustic characteristic mathematic model was built and the acoustic characteristic of PA cell wasThe sensitivity of photoacoustic (PA) sensors strongly depends on the characteristic of PA cell. In the present paper, a novel elliptical differential PA cell was proposed to enhance the signal noise ratio of PA system. An acoustic characteristic mathematic model was built and the acoustic characteristic of PA cell was simulated with COMSOL software. The result shows that peak pressures would occur at the two ends of major axis with a π phase difference when the mixed modes in the cross section of elliptical cell have odd azimuthal nodes along the minor axis. When the half major axis is less than 4 cm, the resonant frequency could be greater than 10kHz and the Q factor could achieve 1 835. Differential detection of PA signal could be realized and the common mode environment noise would be suppressed effectively. The signal noise ratio can be enhanced and high sensitivity detection could be achieved with this high Q factor elliptical differential cell..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1868 (2013)
Application of Rational Ant Colony Optimization to Improve the Reproducibility Degree of Laser Three-Dimensional Copy
CUI Xiao-yan, HUO Zhong-gang, XIN Zhong-hua, TIAN Xiao, and ZHANG Xiao-dong
Three-dimensional (3D) copying of artificial ears and pistol printing are pushing laser three-dimensional copying technique to a new page. Laser three-dimensional scanning is a fresh field in laser application, and plays an irreplaceable part in three-dimensional copying. Its accuracy is the highest among all present cThree-dimensional (3D) copying of artificial ears and pistol printing are pushing laser three-dimensional copying technique to a new page. Laser three-dimensional scanning is a fresh field in laser application, and plays an irreplaceable part in three-dimensional copying. Its accuracy is the highest among all present copying techniques. Reproducibility degree marks the agreement of copied object with the original object on geometry, being the most important index property in laser three-dimensional copying technique. In the present paper, the error of laser three-dimensional copying was analyzed. The conclusion is that the data processing to the point cloud of laser scanning is the key technique to reduce the error and increase the reproducibility degree. The main innovation of this paper is as follows. On the basis of traditional ant colony optimization, rational ant colony optimization algorithm proposed by the author was applied to the laser three-dimensional copying as a new algorithm, and was put into practice. Compared with customary algorithm, rational ant colony optimization algorithm shows distinct advantages in data processing of laser three-dimensional copying, reducing the error and increasing the reproducibility degree of the copy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1873 (2013)
Distribution Characteristics of Soil Heavy Metals in Bamboo Forest of Phyllostachys edulis on Lead-Zinc Orefield
SU Wen-hui, FENG Huan-ying, FAN Shao-hui, LI Xing-jun, and XU Qing-biao
The woodland and farmland soil nearby lead-zinc mine has been polluted seriously due to the mining. Bamboo forest of Phyllostachys edulis has high economic value and is distributed widely in China. The Phyllostachys edulis forest nearby lead-zinc mine was selected, and the distribution characteristics of main heavy metThe woodland and farmland soil nearby lead-zinc mine has been polluted seriously due to the mining. Bamboo forest of Phyllostachys edulis has high economic value and is distributed widely in China. The Phyllostachys edulis forest nearby lead-zinc mine was selected, and the distribution characteristics of main heavy metal Cu, Zn, Pb and Cd in soil were studied. The result showed that the concentration of Cu, Zn, Pb and Cd in bamboo rhizome zone reached 38.10~50.87, 92.24~137.75, 32.04~46.22 and 0.03~0.35 mg·kg-1 respectively, which was lower than that in non-rhizome zone soil significantly. This result indicated that the distribution and concentration of heavy metals in soil were influenced partly by bamboo developed rhizome-root system and human frequent tending management. About the influence of distance from pollution source and slope position, the heavy metals content in soil showed a decreasing trend as the distance increased, and for most elements, the content in soil of the middle slope position was high, and was a little lower in upper slope position..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1877 (2013)
Study of Prediction Models for Oil Thickness Based on Spectral Curve
SUN Peng, SONG Mei-ping, and AN Ju-bai
Nowdays, oil spill accidents on sea occur frequently. It is a practical topic to estimate the amount of spilled oil, which is helpful for the subsequent processing and loss assessment. With the rapid development of hyperspectral remote sensing technology, estimating the oil thickness becomes possible. Firstly, a seriesNowdays, oil spill accidents on sea occur frequently. It is a practical topic to estimate the amount of spilled oil, which is helpful for the subsequent processing and loss assessment. With the rapid development of hyperspectral remote sensing technology, estimating the oil thickness becomes possible. Firstly, a series of oil thicknesses are tested with the AvaSpec Spectrometer to get their corresponding spectral curves. And then the characteristics of the spectral curve are extracted to analyze their relationship with the oil thickness. The study shows that the oil thickness has large correlation with variables based on hyperspectral positions such as Rg, Ro, and vegetation indexes such as RDVI, TVI and Haboudane. Curve fitting, BP neural network and SVD iteration method were chosen to build the prediction models for oil thicknesses. Finally, the analysis and evaluation of each estimating model are provided..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1881 (2013)
Correlation of Visual Spectral Response with Aging and Its Effect on Color Discrimination
HUANG Min, LIU Hao-xue, and LIAO Ning-fang
The variation in normal observers’ color perception and discrimination will occur with the aging effect. The authors carried out a psychophysical experiment with the method of binocular observational technique. Three observers at the age of 21, 32 and 58 were organized to match the 9 printed color samples on EIZO monitThe variation in normal observers’ color perception and discrimination will occur with the aging effect. The authors carried out a psychophysical experiment with the method of binocular observational technique. Three observers at the age of 21, 32 and 58 were organized to match the 9 printed color samples on EIZO monitor with the repetition of 7 times. Groups of data for cross-media color matching with different age were established to investigate the response of photoreceptor cells. The results indicated that with the aging effect the chroma of the matched color will decrease obviously and the spectral response of the blue channel will decrease for blue and purple colors. The results validate the prediction of CIEPO06 model to some extent and provide some theoretical basis and experimental supports for the application of color reproduction and the color evaluation of the products related to age..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1886 (2013)
Backscattering Characteristics of Amphidinium carterae Hulburt
JIANG Ling-ling, WANG Lin, ZHAO Dong-zhi, and WANG Xiang
Variability of the backscattering characteristics of the alga amphidinium carterae hulburt and its interpretation were examined using the measured data performed during July 2012 in the laboratory. The results indicated that the backscattering coefficient has the characteristic of spectral variability, and was highly pVariability of the backscattering characteristics of the alga amphidinium carterae hulburt and its interpretation were examined using the measured data performed during July 2012 in the laboratory. The results indicated that the backscattering coefficient has the characteristic of spectral variability, and was highly power correlated with the chlorophyll concentration, the minimum of the correlation coefficient reached up to 0.96; otherwise, the shape of the particulate backscattering coefficient spectra was also changed from the low chlorophyll concentration to the higher concentration because of the influence of chlorophyll absorption. At the same time, the authors got another value of the particulate backscattering ratio ranging between 0.006 4 and 0.011 6 at 620 nm, although a global increase in particulate backscattering ratio with growing chlorophyll concentration was also visible, but the regularity is not obviously especially at the higher chlorophyll concentration and unlike backscattering coefficient, the spectral shapes of the backscattering ratio remained constant. The authors also found that particle density was one of the main factors controlling the variability of particles backscattering ratio for the pure algal water, and the authors fit a power law function to them and the correlation coefficient at 620 nm was as high as 0.98..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1892 (2013)
Study on Reflectance Spectra Morphological Character of the Hyperspectral Mixed Pixels at Different Component Proportion
ZHU Feng, GONG Hui-li, SUN Tian-lin, HOU Jie, GUO Xiao-meng, and GUO Lin
Under the experimental condition, the hyperspectral reflectance spectra of the mixed pixel of lotus and water body were acquired using the multi-angles dichotic reflex platform and ASD spectrum instrument. The reflectance spectral morphological character index variation of the hyperspectral mixed pixel at different comUnder the experimental condition, the hyperspectral reflectance spectra of the mixed pixel of lotus and water body were acquired using the multi-angles dichotic reflex platform and ASD spectrum instrument. The reflectance spectral morphological character index variation of the hyperspectral mixed pixel at different component proportion was analyzed. The conclusions are as follows: the correlation between these morphological indexes was obvious, and the best morphological index was chosen by removing the index whose R2 was greater than 0.5 (R is correlation coefficient); the variation of different morphological index was obvious; the cluster analysis shows that there was a critical value in the progress of the transformation from the pure pixel (water) to mixed pixel. If the proportion was less than the critical value, the reflectance spectra reflected the reflection characteristics of pure pixel; otherwise, it was the reflection of characteristics of mixed pixel..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1897 (2013)
Research on the Atmospheric Correction for ZY-3 MUX Image
YANG Lei, PAN Zhi-qiang, FU Qiao-yan, HAN Qi-jin, SUN Ke, ZHANG Xue-wen, and WANG Ai-chun
The resolution of the ZY-3 MUX data is 5.8 meter, which is used to the subject classification. It is very difficult to use the dark target method for the atmosphere correction due to the lack of near infrared band in ZY-3 MUX data. The present paper uses the atmospheric correction coefficient look-up table（LUT）construcThe resolution of the ZY-3 MUX data is 5.8 meter, which is used to the subject classification. It is very difficult to use the dark target method for the atmosphere correction due to the lack of near infrared band in ZY-3 MUX data. The present paper uses the atmospheric correction coefficient look-up table（LUT）constructed by the radiation transmission model 6S based on the aerosol optical depth retrieved from the MODIS data for the atmospheric correction of ZY-3 image. To validate the results, the paper compares the surface spectral curves of the gypsum mine and Gobi and the NDVI values from the corrected and TOA reflectance, the relative error of the atmosphere corrected and the ground-based surface reflectance is less than 6%; the atmospheric correction increases the difference between vegetation NDVI and other features NDVI, highlights vegetation monitoring application ability..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1903 (2013)
Analysis of Sensitive Spectral Bands for Burning Status Detection Using Hyper-Spectral Images of Tiangong-01
QIN Xian-lin, ZHU Xi, YANG Fei, ZHAO Kai-rui, PANG Yong, LI Zeng-yuan, LI Xu-zhi, and ZHANG Jiu-xing
To obtain the sensitive spectral bands for detection of information on 4 kinds of burning status, i.e. flaming, smoldering, smoke, and fire scar, with satellite data, analysis was conducted to identify suitable satellite spectral bands for detection of information on these 4 kinds of burning status by using hyper-spectTo obtain the sensitive spectral bands for detection of information on 4 kinds of burning status, i.e. flaming, smoldering, smoke, and fire scar, with satellite data, analysis was conducted to identify suitable satellite spectral bands for detection of information on these 4 kinds of burning status by using hyper-spectrum images of Tiangong-01(TG-01) and employing a method combining statistics and spectral analysis. The results show that: in the hyper-spectral images of TG-01, the spectral bands differ obviously for detection of these 4 kinds of burning status; in all hyper-spectral short-wave infrared channels, the reflectance of flaming is higher than that of all other 3 kinds of burning status, and the reflectance of smoke is the lowest; the reflectance of smoke is higher than that of all other 3 kinds of burning status in the channels corresponding to hyper-spectral visible near-infrared and panchromatic sensors. For spectral band selection, more suitable spectral bands for flaming detection are 1 000.0～1 956.0 and 2 020.0～2 400.0 nm; the suitable spectral bands for identifying smoldering are 930.0～1 000.0 and 1 084.0～2 400.0 nm; the suitable spectral bands for smoke detection is in 400.0～920.0 nm; for fire scar detection, it is suitable to select bands with central wavelengths of 900.0～930.0 and 1 300.0～2 400.0 nm, and then to combine them to construct a detection model..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1908 (2013)
Remote Sensing Image Segmentation Based on a Multiresolution Region Granularity Analysis Method
ZHENG Chen, SUN Ding-qian, and CHEN Xiao-hui
Remote sensing image has abundant granularity information. In order to utilize this information, a multiresolution region granularity analysis method is proposed in the present paper for image segmentation. The proposed method firstly uses the mean shift to obtain the initial over-segmented regions at each resolution oRemote sensing image has abundant granularity information. In order to utilize this information, a multiresolution region granularity analysis method is proposed in the present paper for image segmentation. The proposed method firstly uses the mean shift to obtain the initial over-segmented regions at each resolution of the image, and then extracts the granularity information based on the region size and the region context, the Markov random field is employed to provide the final segmentation result by modeling the spectrum information and the granularity information. The SPOT5 remote sensing images of Pingshuo and the aerial image of Taizhou were tested to evaluate the proposed method. Compared with other spectrum-based methods, our method shows a better performance and results improved the segmentation accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1912 (2013)
Research on Remote Sensing Monitoring of Soil Salinization Based on Measured Hyperspectral and EM38 Data
YAO Yuan, DING Jian-li, Ardak·Kelimu, ZHANG Fang, and LEI Lei
In the present study, the delta oasis between the Weigan River and the Kuqa River was selected as our study area. Firstly, the measured hyperspectral data related to different soil salinization extent was combined with electromagnetic induction instrument (EM38) in order to establish a soil salinization monitoring modeIn the present study, the delta oasis between the Weigan River and the Kuqa River was selected as our study area. Firstly, the measured hyperspectral data related to different soil salinization extent was combined with electromagnetic induction instrument (EM38) in order to establish a soil salinization monitoring model; Secondly, by using the scaling transformation method, the model was adopted to calibrate the soil salinity index calculated from Landsat-TM images. Thirdly, the calibrated Landsat-TM images were used for the retrieval of regional soil salinity, and the retrieved data was verified based on the measured data. We found that at wavelengths of 456, 533, 686 and 1 373 nm, the interpretated data of EM38 were highly correlated with soil spectral reflectance (obtained via first order differentiation transformation of the spectra). Additionally, the soil salinity index model constructed from the combination of 456, 686 and 1 373 nm waveband was the best model among the different salinization monitoring models. The authors’ conclusion is that with R2=0.799 3 (p<0.01), extracting the salinity information at regional scale by combining the electromagnetic and multispectral data performed better than those monitoring models with only salinity index extracted from multispectral remote sensing method (R2=0.587 4, p<0.01). Our findings provides scientific bases for the future studies related to more accurate monitoring and prediction of soil salinization..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1917 (2013)
Nondestructive Discrimination of Waxed Apples Based on Hyperspectral Imaging Technology
GAO Jun-feng, ZHANG Hai-liang, KONG Wen-wen, and HE Yong
The potential of hyperspectral imaging technology was evaluated for discriminating three types of waxed apples. Three types of apples smeared with fruit wax, with industrial wax, and not waxed respectively were imaged by a hyperspectral imaging system with a spectral range of 308～1 024 nm. ENVI software processing platThe potential of hyperspectral imaging technology was evaluated for discriminating three types of waxed apples. Three types of apples smeared with fruit wax, with industrial wax, and not waxed respectively were imaged by a hyperspectral imaging system with a spectral range of 308～1 024 nm. ENVI software processing platform was used for extracting hyperspectral image object of diffuse reflection spectral response characteristics. Eighty four of 126 apple samples were selected randomly as calibration set and the rest were prediction set. After different preprocess, the related mathematical models were established by using the partial least squares (PLS), the least squares support vector machine (LS-SVM) and BP neural network methods and so on. The results showed that the model of MSC-SPA-LSSVM was the best to discriminate three kinds of waxed apples with 100%, 100% and 92.86% correct prediction respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1922 (2013)
Retrieval Method for Estimating Snow Depth Using Hyperspectral Data in Snowmelt Period
XU Qian, LIU Zhi-hui, and FANG Shi-feng
The snow surface reflectance spectra with different depth in snowmelt period and snow depth data were measured and its correlation was analyzed. The characteristic absorption band data of the valley with higher correlation were used to establish a single band snow depth regression model. The highest contribution rate oThe snow surface reflectance spectra with different depth in snowmelt period and snow depth data were measured and its correlation was analyzed. The characteristic absorption band data of the valley with higher correlation were used to establish a single band snow depth regression model. The highest contribution rate of the band was selected as the input variable of the neural network model to retrieve snow depth. The results show that in Juntang Lake area, near 1 022, 1 241 and 1 492 nm exists characteristic absorption valley of snow, and compared to estimation accuracy of the single-band inversion of snow depth model (R2=0.53), ANN-BP model has a higher inversion level, and determination coefficient (R2=0.86, RMSE=0.67) was obtained with 4 nodes in hidden layers, indicating that ANN-BP model can greatly improve the ability of inversion of snow depth with hyperspectral data..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1927 (2013)
Research on Hyperspectral Remote Sensing Inversion of Barrier Factors in Saline-Alkaline Land Use
HAN Ji-chang, and LI Xiao-ming
In the present paper, the meliorated saline-alkaline land by mixing sand in the north of Shaanxi province was chosen as the study area. The growth situation of the corn in the study area was measured, and soil samples and hyperspectral data were collected. The barrier factors for saline-alkaline land use were obtained In the present paper, the meliorated saline-alkaline land by mixing sand in the north of Shaanxi province was chosen as the study area. The growth situation of the corn in the study area was measured, and soil samples and hyperspectral data were collected. The barrier factors for saline-alkaline land use were obtained by analysing the properties of soil samples. And the hyperspectral characteristics of the barrier factors were studied to elicit the quantitative inverse model, and the accuracy was verified. The study results indicated that the salt content in soil was the primary factor restricting the saline-alkaline land use, and capillary porosity was also the barrier factor because of its good correlation with the salt content. The precisions of quantitative inverse model of salt content and capillary porosity with hyperspectral data were good (the determinate coefficients R2 were 0.938 and 0.973). The test result with testing points showed that there were good correlations between the measured value and predicted value of salt content and capillary porosity (the slope was near to 1, and R2 was 0.840 4 and 0.796 5), the accuracy was good. It is of great promotion for guiding the saline-alkaline land consolidation and use that the barrier factors for saline-alkaline land use were interpreted quantitatively by hyperspectral data..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1932 (2013)
Application of Argon-Nitrogen Mixed Gas Inductively Coupled Plasma in Elements and Isotopes Analysis
LIU Sheng-hua, CHEN Tao, LI Zhen, WANG Li-yun, LIU Yong-sheng, HU Sheng-hong, and HU Zhao-chu
To improve the precision and accuracy of elements and isotopes analysis in traditional Ar-ICP, the addition of nitrogen in ICP has been widely used. The present review focused on the discussions of the basic physical and chemical properties of the Ar-N2 mixed gas inductively coupled plasma and the mechanisms of the speTo improve the precision and accuracy of elements and isotopes analysis in traditional Ar-ICP, the addition of nitrogen in ICP has been widely used. The present review focused on the discussions of the basic physical and chemical properties of the Ar-N2 mixed gas inductively coupled plasma and the mechanisms of the special nature of Ar-N2 mixed gas plasma. The applications of Ar-N2 inductively coupled plasma in spectral analysis and mass spectrometry analysis in the past 40 years were summarized. The authors also give an overall outlook on the application of this technology..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1936 (2013)
Comparison of Fluorescence Spectroscopy and Plasma-Mass Spectrometry Results of the Meso/Cenozoic Basic Rocks in SE China and Its Geo-Implication
LOU Feng, CHEN Guo-neng, CHEN Guo-hui, and HUANG Hai-hua
With comparison of the fluorescence spectroscopy and plasma-mass spectroscopy analysis results of the Meso/Cenozoic basic rocks of SE China, the authors found that the average SiO2 content of the Mesozoic basic rocks in this area is about 50%, while that of the Cenozoic basic rocks is about 43%. The former belongs to tWith comparison of the fluorescence spectroscopy and plasma-mass spectroscopy analysis results of the Meso/Cenozoic basic rocks of SE China, the authors found that the average SiO2 content of the Mesozoic basic rocks in this area is about 50%, while that of the Cenozoic basic rocks is about 43%. The former belongs to the basic group and the later to the ultrabasic group in igneous rock classification. Cenozoic basalts, accompanied with high magnesium content and low silica-alumina component, are obviously basic or ultrabasic rocks. Distinctive difference in the content of trace elements and of REE is also presented between the Mesozoic and the Cenozoic basic rocks. Distribution models of both trace elements and REE of the Mesozoic basic rocks are similar to those of the upper crust, and the models of the Cenozoic basic rocks are like those of OIB, indicating that basic rocks of the Cenozoic and OIB should originate from the mantle while that of the Mesozoic is from the bottom part of the upper crust with relationship to the evolution of the Mesozoic crustal magma layer of this area..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1943 (2013)
Study on Trace Elements of Lake Sediments by ICP-AES and XRF Core Scanning
CHENG Ai-ying, YU Jun-qing, GAO Chun-liang, ZHANG Li-sha, and HE Xian-hu
It is the first time to study sediment of Toson lake in Qaidam Basin. Trace elements including Cd, Cr, Cu, Zn and Pb in lake sediment were measured by ICP-AES method, studied and optimized from different resolution methods respectively, and finally determined a optimum pretreatment system for sediment of Toson lake, naIt is the first time to study sediment of Toson lake in Qaidam Basin. Trace elements including Cd, Cr, Cu, Zn and Pb in lake sediment were measured by ICP-AES method, studied and optimized from different resolution methods respectively, and finally determined a optimum pretreatment system for sediment of Toson lake, namely, HCl-HNO3-HF-HClO4-H2O2 system in the proportions of 5∶5∶5∶1∶1 was determined. At the same time, the data measured by XRF core scanning were compared, the use of moisture content correction method was analyzed, and the influence of the moisture content on the scanning method was discussed. The results showed that, compared to the background value, the contents of Cd and Zn were a little higher, the content of Cr, Cu and Pb was within the background value limits. XRF core scanning was controlled by sediment elements as well as water content in sediment to some extent. The results by the two methods showed a significant positive correlation, with the correlation coefficient up to 0.673～0.925, and they have a great comparability..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1949 (2013)
Study on the Determination of 14 Inorganic Elements in Coffee by Inductively Coupled Plasma Mass Spectrometry
NIE Xi-du, and FU Liang
Samples of coffee were digested by microwave digestion, and inorganic elements amounts of Na, Mg, P, Ca, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Mo and Pb in sample solutions were determined by inductively coupled plasma mass spectrometry (ICP-MS). HNO3+H2O2 was used to achieve the complete decomposition of the organic matrix Samples of coffee were digested by microwave digestion, and inorganic elements amounts of Na, Mg, P, Ca, Cr, Mn, Fe, Co, Cu, Zn, As, Se, Mo and Pb in sample solutions were determined by inductively coupled plasma mass spectrometry (ICP-MS). HNO3+H2O2 was used to achieve the complete decomposition of the organic matrix in a closed-vessel microwave oven. The working parameters of the instrument were optimized. The results showed that the relative standard deviation (RSD) was less than 3.84% for all the elements, and the recovery was found to be 92.00%～106.52% by adding standard recovery experiment. This method was simple, sensitive and precise and can perform simultaneous multi-elements determination of coffee, which could satisfy the sample examination request and provide scientific rationale for determining inorganic elements of coffee..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1953 (2013)
Determination of Ru, Rh and Pd in 30%Trialkyl Phosphine Oxide(TRPO)-Kerosene by Inductively Coupled Plasma-Atomic Emission Spectrum (ICP-AES)
WANG Jian-chen, and ZHANG Lin
The determination method of Ru, Rh and Pd in 30%TRPO-kerosene ICP-AES was studied by using aqueous calibration reference solution and choosing ethanol as diluent. The effects of the contents of 30%TRPO-kerosene and aqueous solution and the concentration of HNO3 in 30%TRPO-kerosene on the intensities of Ru, Rh and Pd weThe determination method of Ru, Rh and Pd in 30%TRPO-kerosene ICP-AES was studied by using aqueous calibration reference solution and choosing ethanol as diluent. The effects of the contents of 30%TRPO-kerosene and aqueous solution and the concentration of HNO3 in 30%TRPO-kerosene on the intensities of Ru, Rh and Pd were described. The optimized condition for preparing samples and calibration solutions was chosen as follows: The contents of 30%TRPO-kerosene and aqueous phase were 10%(Ｖ/Ｖ) and 5% (Ｖ/Ｖ) respectively and the concentration of HNO3 30%TRPO-kerosene was 0.20 mol·L-1. The determination method of Au, Ru and Pd was set up according to the above condition. The detection limit, precision and recovery ratio of Ru, Rh and Pd are well. The method is not only used in determination of Au, Ru and Pd in 30%TRPO-kerosene, but also used in other organic phases..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1957 (2013)
Study on the Simultaneous Determintion of Various Components in Cement Samples by Inductive Coupled Plasma-Atomic Emission Spectrometry
XU Xue-qin
A simple and rapid method for determination of CaO, MgO, Fe2O3, Al2O3 and TiO2 in cement samples by inductive coupled plasma-atomic emission spectrometry (ICP-AES) was developed. In order to carry out the analysis, the cement samples were dissolved with mixed aqua regia, hydrofluoric acid, perchloric acid, hydrochloricA simple and rapid method for determination of CaO, MgO, Fe2O3, Al2O3 and TiO2 in cement samples by inductive coupled plasma-atomic emission spectrometry (ICP-AES) was developed. In order to carry out the analysis, the cement samples were dissolved with mixed aqua regia, hydrofluoric acid, perchloric acid, hydrochloric acid, and the standard solution was prepared by a series of standard cement samples. The matrix interference and the mutual interference of elements under test were studied by ICP-AES. The detection limits are in the range of 3.79×10-4~1.07×10-2 μg·mL-1. The recovery rates and relative standard deviations (RSD) of the method are in the range of 87.5%~105.6% and less than 1% respectively. Research results show that the method can meet the requirements of rapid chemical analysis for cement..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1961 (2013)
Analysis of X-Ray Fluorescence Spectroscopy and Plasma Mass Spectrometry of the Guidong Granite Body and Its Implications to Granite Evolution
LI Hong-wei, CHEN Guo-neng, and PENG Zhuo-lun1
The Guidong composite granite body (CGB) located in the north Guangdong Province consists of numerous rock bodies formed respectively in the early and late Jurassic and early Cretaceous. Analysis of the granites of different period with X-ray fluorescence spectroscopy and plasma mass spectrometry indicates: (1) From thThe Guidong composite granite body (CGB) located in the north Guangdong Province consists of numerous rock bodies formed respectively in the early and late Jurassic and early Cretaceous. Analysis of the granites of different period with X-ray fluorescence spectroscopy and plasma mass spectrometry indicates: (1) From the top of a granite body downwards, the felsic components of rock decrease, while the mafic and ∑REE, LREE/HREE, (La/Yb)N, as well as δEu value increase, suggesting the material differentiation in the in-situ melting of crustal rocks and crystallisation of magma; (2) From old to young of the different period granite-massifs in the Guidong CGB, the felsic compositions totally decrease, and the mafic components, ∑REE, LREE/HREE, (La/Yb)N, and δEu value increase as well, implying multiple crustal melting (remelting) events in the Mesozoic in this area; and (3) Primitive mantle-normalized spider diagram for trace elements of Guidong CGB suggests high maturity of the crust involved in the in-situ melting..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1965 (2013)
Infrared Spectra and XRD Characteristics of Alunite in the Zijinshan Gold-Copper Deposit
WANG Cui-zhi, and ZHANG Wen-yuan
The structural characteristics and composition of alunite in the Zijinshan gold-copper deposit were studied by infrared absorption spectroscopy and X-ray powder diffraction analysis. The results show that infrared spectral absorption peaks, the growth degree of crystal faces (006) and (004）, and crystal cell parametersThe structural characteristics and composition of alunite in the Zijinshan gold-copper deposit were studied by infrared absorption spectroscopy and X-ray powder diffraction analysis. The results show that infrared spectral absorption peaks, the growth degree of crystal faces (006) and (004）, and crystal cell parameters of the alunite display gradually decreasing trend from the crater to northwest along the metallogenic belt. Combined with electron probe analysis results, we go further and obtain that the alunite mainly belongs to potassium alunite, and the characteristics of infrared spectra and XRD of the alunite mainly have relation to the content of potassium of the alunite in different parts of volcanic mechanism. Near the crater, with higher temperature, it is helpful for the isomorphism replacement between sodium and potassium, the content of sodium is higher and the content of potassium is lower relatively in the alunite; and away from the crater, the temperature is relatively lower, it is against the isomorphism replacement between sodium and potassium, the content of sodium is lower, and the content of potassium is higher relatively in the alunite..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1969 (2013)
Study on the Traditional Lime Mortar from the Memorial Archway in the Southern Anhui Province
WEI Guo-feng, SUN Sheng, WANG Cheng-xing, ZHANG Bing-jian, and CHEN Xi-min
The traditional lime mortar was investigated by means of scanning electron microscope (SEM), X-ray diffractometry and Fourier transform infrared spectrometry (FTIR). The results show that the mortar from the memorial archway in the southern Anhui province was the organic-inorganic composite materials composed of lime wThe traditional lime mortar was investigated by means of scanning electron microscope (SEM), X-ray diffractometry and Fourier transform infrared spectrometry (FTIR). The results show that the mortar from the memorial archway in the southern Anhui province was the organic-inorganic composite materials composed of lime with tung oil or sticky rice. It was found that the excellent performance of the tung oil-lime mortar can be explained by the compact lamellar organic-inorganic composite structure that was produced by carbonization reaction of lime, cross-linking reactions of tung oil and oxygen and complexing reaction of Ca2+ and —COO－. The compact micro-structure of sticky rice-lime mortar, which was produced due to carbonation process of lime controlled by amylopectin, should be the cause of the good performance of this kind of organic-inorganic mortar..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1973 (2013)
Mineralogical and Spectral Characteristics of Copper Pectolite
ZHENG Chen, YIN Zuo-wei, YIN Ke, LI Yi-long, CHEN Quan-li, and LIU Yun-gui
Copper pectolite, a type of pectolite with blue stripes, is a rare gem material with a great market prospect. Mineralogy and genesis were investigated using X-ray diffraction (XRD), Fourier infrared absorption spectroscopy (FTIR), Raman spectroscopy (Raman), scanning electron microscopes (SEM) and ultraviolet-visible sCopper pectolite, a type of pectolite with blue stripes, is a rare gem material with a great market prospect. Mineralogy and genesis were investigated using X-ray diffraction (XRD), Fourier infrared absorption spectroscopy (FTIR), Raman spectroscopy (Raman), scanning electron microscopes (SEM) and ultraviolet-visible spectrometer(UV-VIS) to understand the mineralogical compositions and characteristics of the parts with different color. XRD, FTIR and Raman result showed that copper pectolite is composed of pectolite and minor calcite, consistent with the result of SEM. FTIR showed that an obvious band at 1 500 cm-1 with 883 and 710 cm-1 occurred on the white part that contain minor calcite, while the band was absent on the blue part. UV-Vis absorption spectroscopy analysis showed that the blue part has 640 nm absorption band in the UV area that indicates containing elements Cu. The different mineralogical compositions of the white and blue part indicate their different geological conditions.
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1977 (2013)
Impact and Improvement of the Mechanical Shutter on Large-Array Filter-Type Multispectral Imaging System
ZHAO Bao-wei, XIANGLI Bin, Lv Qun-bo, ZHANG Gui-feng, and LIU Jiu
The present paper analyzes the impact of mechanical shutter on the spectral image acquisition and processing of large-array filter-type multispectral imaging system. The final image quality relies highly on the mechanical shutter due to the fluctuation at exposure time. The conventional mechanical shutter’s structure aThe present paper analyzes the impact of mechanical shutter on the spectral image acquisition and processing of large-array filter-type multispectral imaging system. The final image quality relies highly on the mechanical shutter due to the fluctuation at exposure time. The conventional mechanical shutter’s structure and driving method was analyzed to find out the key fact for its poor stability. An improved method of mechanical transmission and circuit driving was proposed. Laboratory experiments showed that with the improved design strategy, the maximum rate of change between adjacent exposures was reduced from 15.05% to 0.96%, which is a great improvement of the exposure time stability. Field test was also carried out and the results show that the combined color images are closer to the realistic targets and no abrupt color change iwas found. It’s of great significance for practical application in multispectral image process, interpretation and target identification..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1982 (2013)
Imaging Quality Evaluation of Computational Imaging Spectrometry
QIAN Lu-lu, XIANGLI Bin, Lv Qun-bo, ZHOU Zhi-liang, and FU Qiang
As a novel imaging spectrometry, computational imaging spectrometry（CIS）has the advantages of high throughput, snapshot imaging etc. However, there is little research on imaging quality evaluation of CIS system. In the present paper, a quantitive evaluation method for imaging quality of CIS system was presented. ISO 12As a novel imaging spectrometry, computational imaging spectrometry（CIS）has the advantages of high throughput, snapshot imaging etc. However, there is little research on imaging quality evaluation of CIS system. In the present paper, a quantitive evaluation method for imaging quality of CIS system was presented. ISO 12233 chart was used as the objective source, and then imaging and reconstruction of the spatial-spectral information was provided. Calculating modulation transfer functions (MTFs) for the reconstructed images was considered as the criterion of the imaging quality evaluation of CIS system. The result shows that MTFs for single-frame sampling decrease rapidly with the aliasing spectral number increasing. When the number of the aliasing spectra is 9, MTF for the reconstructed image decreases by 50% compared to the original scene. This work helps better understand the pros and cons of CIS system and arrange the aliasing spectral number reasonably to reconstruct the object scene precisely..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1987 (2013)
Optical Path Difference in Off-Plane Quasi-Littrow Dispersion Mountings
ZHANG Yin-xin, YANG Huai-dong, HUANG Zhan-hua, and JIN Guo-fan
The present paper analyzes the relative relation between the meridian and sagittal rays in off-plane quasi-Littrow (OP-QL) dispersion mountings. It’s concluded that the off-plane angle will cause the rotation of the beam and result in the mismatch between the sagittal beams on different optical elements. Therefore the The present paper analyzes the relative relation between the meridian and sagittal rays in off-plane quasi-Littrow (OP-QL) dispersion mountings. It’s concluded that the off-plane angle will cause the rotation of the beam and result in the mismatch between the sagittal beams on different optical elements. Therefore the total optical path difference (OPD) should be an accumulation of corresponding beams instead of the sagittal beam of each element itself. Then, a directional derivative based method is put forward to calculate the OPD for spherical mirrors in various directions. Based on the method, the numerical OPD for OP-QL mountings is solved. Finally, this methodology is validated with both echelette and echelle examples..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1992 (2013)
General Calculation Method of Diffraction Efficiency of Concave Blazed Gratings
LI Ting, HUANG Yuan-shen, XU Bang-lian, LI Bai-cheng, ZHANG Da-wei, TAO Chun-xian, LING Jin-zhong, and ZHUANG Song-lin
In order to make diffraction energy of concave gratings more concentrated in the desired order, the present paper puts forward that the concave blazed grating with variable groove angles could be fabricated on the concave substrates by mechanical ruling method, and the theoretical method of simultaneously calculating tIn order to make diffraction energy of concave gratings more concentrated in the desired order, the present paper puts forward that the concave blazed grating with variable groove angles could be fabricated on the concave substrates by mechanical ruling method, and the theoretical method of simultaneously calculating the diffraction efficiency in the main section and non-main section is deduced by using Fresnel-Kirchhoff’s diffraction formula, which makes up the shortage of the diffraction efficiency calculated only in the main section. Finally, the diffraction efficiency curves varied with wavelength is simulated by Matlab software, and the variation laws of the diffraction efficiency are compared for different production methods and application parameters, which provides a valuable reference for the design and production of the concave gratings..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1997 (2013)
Study on the Characteristics of Radiance Calibration Using Nonuniformity Extended Source
WANG Jian-wei, HUANG Min, XIANGLI Bin, and TU Xiao-long
Integrating sphere and diffuser are always used as extended source, and they have different effects on radiance calibration of imaging spectrometer with parameter difference. In the present paper, a mathematical model based on the theory of radiative transfer and calibration principle is founded to calculate the irradiIntegrating sphere and diffuser are always used as extended source, and they have different effects on radiance calibration of imaging spectrometer with parameter difference. In the present paper, a mathematical model based on the theory of radiative transfer and calibration principle is founded to calculate the irradiance and calibration coefficients on CCD, taking relatively poor uniformity lights-board calibration system for example. The effects of the nonuniformity on the calibration was analyzed, which makes up the correlation of calibration coefficient matrix under ideal and unideal situation. The results show that the nonuniformity makes the viewing angle and the position of the point of intersection of the optical axis and the diffuse reflection plate have relatively large effects on calibration, while the observing distance’s effect is small; under different viewing angles, a deviation value can be found that makes the calibration results closest to the desired results. So, the calibration error can be reduced by choosing appropriate deviation value..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 2002 (2013)
Hadamard Transform Spectral Imager of Adaptive Spectral Resolution Based on DMD
XU Jun, LIU Zhi-wei, JIANG Nan, ZHU Zhen-min, LIU Hai-wen, and LI Bin-cheng
Digital micro-mirror device (DMD) can be controlled to form Hadamard encoding masks flexibly and efficiently. A kind of Hadamard transform spectral imager of adaptive spectral resolution based on DMD is proposed. The structure and the working principle of the instrument are described and the implementation method of adDigital micro-mirror device (DMD) can be controlled to form Hadamard encoding masks flexibly and efficiently. A kind of Hadamard transform spectral imager of adaptive spectral resolution based on DMD is proposed. The structure and the working principle of the instrument are described and the implementation method of adaptive spectral resolution is analyzed. It can adjust the spectral resolution according to the target and the observational requirements, and a reasonable compromise can be reached between the spectral accuracy and the computation of data. It not only meets the requirements of the target classification and recognition, but also improves the speed of data transmission and processing..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 2006 (2013)
A Novel Scheme SVR(Haar) for Automatically Estimating Stellar Atmospheric Parameters from Spectrum
LU Yu, LI Xiang-ru, WANG Yong-jun, and YANG Tan
A novel scheme SVR(Haar) is proposed in the present work for automatically estimating the physical parameters of stellar spectra. The observed spectrum is disturbed usually by noise which is caused by the universe radiation, the atmosphere and observation equipment. Furthermore, the noise usually is the component of thA novel scheme SVR(Haar) is proposed in the present work for automatically estimating the physical parameters of stellar spectra. The observed spectrum is disturbed usually by noise which is caused by the universe radiation, the atmosphere and observation equipment. Furthermore, the noise usually is the component of the spectrum with higher frequency. Therefore, we propose to extract features with Haar wavelet by removing higher frequency components. Researches show that this procedure can improve the accuracy of the estimation. Secondly, the support vector regression model is employed for estimating physical parameters of the stellar spectra. In this method, the ε insensitive domain techniques can further improve the probability to the slight distortion of the spectrum from imperfect calibration, and enhance the robustness of the proposed scheme. To check the effectiveness of the proposed scheme SVR(Haar), we did experiments extensively on authoritative simulated stellar spectra and real spectra observed by SLOAN, and compared it with the typical methods in the literature. The results show that the SVR(Haar) is better than the principal component analysis and non-parametric regression model in the literature..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 2010 (2013)
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 33, Issue 7, 1 (2013)
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