Journals >Spectroscopy and Spectral Analysis
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2015
Volume: 35 Issue 8
60 Article(s)
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Research Article
[in Chinese]
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 1 (2015)
The Study about Spectrum Characteristic Analysis Method in the Induction Period of Gas Explosion Flame
LIU Kui, LI Xiao-bin, and ZHENG Dan
Through analyzing the spectroscopic data of gas explosion flame whose volume fraction is 10% under a small scale experimental condition based on the target emission spectrum analysis methods;presents the gas explosion flame spectrum characteristic analysis methods about frequency domain feature parameters which includeThrough analyzing the spectroscopic data of gas explosion flame whose volume fraction is 10% under a small scale experimental condition based on the target emission spectrum analysis methods;presents the gas explosion flame spectrum characteristic analysis methods about frequency domain feature parameters which include spectral density,band radiation light intensity,band average deviation,the time domain characteristic parameter which include band radiation energy,time average and deviation and the characteristic parameters which include skewness,kurtosis and half width;obtain the results that in the vicinity of somewhere,the spectral density converts between positive and negative in the range of 1nm that the light intensity of gas explosion flame changes dramatically;the definite integral of gas explosion flame spectral waveband is strongest in the 550~900 nm;with the wavelength increases the detected time grow,the gas explosion flame spectral signal strength attenuation trends on the whole and after the peak interval appeared in the process of decay have weaken the strength of the enhanced;results show that the target emission spectrum analysis methods can be applied to do the semi-quantitative analysis of dynamic process of gas explosion,the analysis spectral characteristics can be taken as a standard to detecting gas explosion flame..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2067 (2015)
Terahertz Absorption Spectra Simulation of Glutamine Based on Quantum-Chemical Calculation
ZHANG Tian-yao, ZHANG Zhao-hui, ZHAO Xiao-yan, ZHANG Han, YAN Fang, and QIAN Ping
With simulation of absorption spectra in THz region based on quantum-chemical calculation,the THz absorption features of target materials can be assigned with theoretical normal vibration modes.This is necessary for deeply understanding the origin of THz absorption spectra.The reliabilities of simulation results mainlyWith simulation of absorption spectra in THz region based on quantum-chemical calculation,the THz absorption features of target materials can be assigned with theoretical normal vibration modes.This is necessary for deeply understanding the origin of THz absorption spectra.The reliabilities of simulation results mainly depend on the initial structures and theoretical methods used throughout the calculation.In our study,we utilized THz-TDS to obtain the THz absorption spectrum of solid-state L-glutamine.Then three quantum-chemical calculation schemes with different initial structures commonly used in previous studies were proposed to study the inter-molecular interactions’ contribution to the THz absorption of glutamine,containing monomer structure,dimer structure and crystal unit cell structure.After structure optimization and vibration modes’ calculation based on density functional theory,the calculation results were converted to absorption spectra by Lorentzian line shape function for visual comparison with experimental spectra.The result of dimmer structure is better than monomer structure in number of absorption features while worse than crystal unit cell structure in position of absorption peaks.With the most reliable simulation result from crystal unit cell calculation,we successfully assigned all three experimental absorption peaks of glutamine ranged from 0.3 to 2.6 THz with overall vibration modes.Our study reveals that the crystal unit cell should be used as initial structure during theoretical simulation of solid-state samples’ THz absorption spectrum which comprehensively considers not only the intra-molecular interactions but also inter-molecular interactions..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2073 (2015)
High-Sensitive Carbon Dioxide Detection Using Quartz-Enhanced Photoacoustic Spectroscopy with a 2.0μm Distributed Feedback Laser
LIU Xiao-li, WU Hong-peng, SHAO Jie, DONG Lei, ZHANG Lei, MA Wei-guang, YIN Wang-bao, and JIA Suo-tang
A carbon dioxide (CO2) sensor is developed using quartz enhanced photoacoustic spectroscopy (QEPAS) with a 2.0 μm distributed feedback diode laser.The detection is based on a 2ｆ wavelength-modulation spectroscopy approach by dithering and scanning the laser current.The laser modulation depth is optimized at normal atmoA carbon dioxide (CO2) sensor is developed using quartz enhanced photoacoustic spectroscopy (QEPAS) with a 2.0 μm distributed feedback diode laser.The detection is based on a 2ｆ wavelength-modulation spectroscopy approach by dithering and scanning the laser current.The laser modulation depth is optimized at normal atmosphere pressure and room temperature.The influence of the H2O presence in the sample gas mixture on the CO2 sensor performance is also investigated.The results show that,with 1% CO2 concentration,the H2O in the concentration ranges of 0 to 0.2% has an effect on the CO2 signal amplitude and phase,and the largest amplitude difference is ~2.1 times.When the H2O concentration is over 0.2%,the CO2 signal amplitude is saturated and remains steady.Atmospheric CO2 concentration is well measured using the optimal sensor parameters.Benefiting from the strong absorption line intensity at 4 989.97 cm-1,a detection limit of 19 ppm (1σ,300 ms averaging time) is achieved,which corresponds to a normalized noise equivalent absorption coefficient of 4.71×10-9 cm-1·W·Hz-1/2..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2078 (2015)
A New Method of Accurately Extracting Spectral Values for Discrete Sampling Points
Lv Zhen-zhen, LIU Guang-ming, and YANG Jin-song
In the establishment of remote sensing information inversion model,the actual measured data of discrete sampling points and the corresponding spectrum data to pixels of remote sensing image,are used to establish the relation,thus to realize the goal of information retrieval.Accurate extraction of spectrum value is veryIn the establishment of remote sensing information inversion model,the actual measured data of discrete sampling points and the corresponding spectrum data to pixels of remote sensing image,are used to establish the relation,thus to realize the goal of information retrieval.Accurate extraction of spectrum value is very important to establish the remote sensing inversion mode.Converting target spot layer to ROI (region of interest) and then saving the ROI as ASCII is one of the methods that researchers often used to extract the spectral values.Analyzing the coordinate and spectrum values extracted using original coordinate in ENVI,we found that the extracted and original coordinate were not inconsistent and part of spectrum values not belong to the pixel containing the sampling point.The inversion model based on the above information cannot really reflect relationship between the target properties and spectral values;so that the model is meaningless.We equally divided the pixel into four parts and summed up the law.It was found that only when the sampling points distributed in the upper left corner of pixels,the extracted values were correct.On the basis of the above methods,this paper systematically studied the principle of extraction target coordinate and spectral values,and summarized the rule.A new method for extracting spectral parameters of the pixel that sampling point located in the environment of ENVI software.Firstly,pixel sampling point coordinates for any of the four corner points were extracted by the sample points with original coordinate in ENVI.Secondly,the sampling points were judged in which partition of pixel by comparing the absolute values of difference longitude and latitude of the original and extraction coordinates.Lastly,all points were adjusted to the upper left corner of pixels by symmetry principle and spectrum values were extracted by the same way in the first step.The results indicated that the extracted spectrum values of all points were accurate.Experiment on OLI (Operational Land Imager),TM and ETM+ images showed that this method can accurately extract the discrete spectrum value,and as well,clear principle,simple and feasible operation,strong applicability,This paper provides a new idea for remote sensing image extraction of discrete point spectrum..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2083 (2015)
In Situ Infrared Spectroscopic Determination of Enzyme Activity
REN Zhong-yuan, and WU Yu-qing
A real-time infrared (IR) spectroscopy measurement is an effective means to obtain enzymatic information either in vitro or in living cells,as it can provide direct,continue test of biomacromolecule reactions.The principles of measurements are performed basing on the fact that the absorption bands in spectra of reactanA real-time infrared (IR) spectroscopy measurement is an effective means to obtain enzymatic information either in vitro or in living cells,as it can provide direct,continue test of biomacromolecule reactions.The principles of measurements are performed basing on the fact that the absorption bands in spectra of reactants and products are usually separated to each other and changed independently with time.Therefore,it is possible to measure the enzymatic efficiency at any reaction time according to the changes of characteristic band,from either reactant or product.That is,IR spectroscopy can be used to obtain intracellular structural information during the cells metabolic processes,as which can provide detailed and reliable scientific evidences.In this paper,we summarized the new developments of IR spectra in the in vitro enzymatic assay for several representative enzymes,as well the screening of enzyme inhibitors,which was further extended to the identical aspect by using living cells as detection model.Such important enzymatic examination closes to the physiological conditions without labeling,supplying structural information of the related biomolecules.The developing trends of IR spectra are discussed and the perspectives of it in the research area are also provided in this review..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2087 (2015)
The Impacts of the Variation of Myanmar Jade Component on Its Infrared Spectroscopy
WANG Ya-jun, SHI Bin, YUAN Xin-qiang, PEI Lei, CHEN Tao, and XIE Xiao-li
Myanmar jade is crystalline aggregate with the major mineral of jadeite.Jadeite can be represented by the crystal-chemical formula NaAlSi2O6.Isomorphous substitution occurs in the natural jadeite frequently,with replacement of Na by Ca,and replacement of Al by Mg,Fe,Cr etcetera,which makes the component of Myanmar jadeMyanmar jade is crystalline aggregate with the major mineral of jadeite.Jadeite can be represented by the crystal-chemical formula NaAlSi2O6.Isomorphous substitution occurs in the natural jadeite frequently,with replacement of Na by Ca,and replacement of Al by Mg,Fe,Cr etcetera,which makes the component of Myanmar jade much more complex and leads to the variation of its physical features,including color,transparency,refractive index,specific gravity and infrared spectrum characteristics,forming different types of Myanmar jade.The studies show that the vibrational spectra characteristics of the Myanmar jade varies depending on the substitution of different elements.In this work,we studied the impacts of the variation of Myanmar jade component on its infrared spectroscopy.10 Myanmar jade samples which consisted of different chemical composition were measured using Fourier Transform Infrared Spectroscopy (FTIR),and results show that the IR absorption peaks shift to higher wave numbers,as the atomic ratio of Na/Na+Ca of the samples increases.In the low wave number region,the wave number of the IR absorption peaks at 424,576 and 658 cm-1 and the atomic ratio of Na/Na+Ca of the samples share fine linear correlation,and the correlation coefficients (R2) are,in order,R21=0.944 2,R22=0.928 3,R23=0.909 7.We can utilize infrared spectrum technologies combined with linear model built by us in this work to predicate the atomic ratio of Na/Na+Ca of the unknown Myanmar jade samples.As the atomic ratio of Na/Na+Ca of the unknown Myanmar jade samples equals 0.8,the IR absorption peaks should be at 658.7,574.5,422.5 cm-1.If the wavenumbers of the IR absorption peaks are less than 658.7,574.5 and 422.5 cm-1,the atomic ratio of Na/Na+Ca of the unknown Myanmar jade samples is less than 0.8,which is indicating that the unknown Myanmar jade sample isomphacitic jade,while the wavenumbers of the IR absorption peaks are more than 658.7,574.5 and 422.5 cm-1,the atomic ratio of Na/Na+Ca of the unknown Myanmar jade samples is more than 0.8,which is indicating that the unknown Myanmar jade sample is jadeitic jade.The studies of this work offer a super-quick time-saving and labor-saving nondestructivetesting method for using infrared spectrum technologies to test Myanmar jade samples,analyze their component and predicate which mineral styles the unknown samples are..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2094 (2015)
Two-Dimensional Hetero-Spectral Near-Infrared and Mid-Infrared Correlation Spectroscopy for Discrimination Adulterated Milk
YU Ge, YANG Ren-jie, Lv Ai-jun, and TAN En-zhong
New approach for discriminant analysis of adulterated milk is proposed based on combining hetero-spectral two-dimensional (2D) near-infrared (NIR) and mid-infrared (IR) correlation spectroscopy along with multi-way partial least squares discriminant analysis (NPLS-DA).Firstly,36 pure milk samples were collected and 36 New approach for discriminant analysis of adulterated milk is proposed based on combining hetero-spectral two-dimensional (2D) near-infrared (NIR) and mid-infrared (IR) correlation spectroscopy along with multi-way partial least squares discriminant analysis (NPLS-DA).Firstly,36 pure milk samples were collected and 36 adulterated milk with starch samples (0.01 to 1 g·L-1) were prepared by adding appropriate mass of starch into pure milk.Then,one-dimensional NIR transmittance spectra and IR attenuated total reflection spectra of pure milk and adulterated milk with starch were measured at room temperature.And the synchronous 2D NIR-IR (4 200~4 800 vs.900~1 700 cm-1) correlation spectra of all samples were calculated.Due to the trace of adulterants,the synchronous 2D IR-NIR correlation spectral differences between adulterated milk with starch and pure milk are very subtle.Consequently,it was impossible to directly distinguish whether the sample was pure milk or adulterated milk.Finally,2D IR-NIR correlation spectra were to build a discriminant model to classify adulterated milk and pure milk.The classification accuracy rates of samples in calibration set and in prediction set were 95.8% and 100% respectively.Also,the NPLS-DA models were built based on 2D NIR and 2D IR correlation spectra,respectively.The classification accuracy rates of samples in prediction set were 95.8%.Comparison results showed that the NPLS-DA model could provide better results using 2D NIR-IR correlation spectra than using 2D NIR,and 2D IR correlation spectra.The proposed method can not only effectively extract the feature information of adulterants in milk,but also explores a new perspective method for detection of adulterated food..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2099 (2015)
NIRS for Predicting Nutritive Value of Elymus Sibiricus
YAN Xu, BAI Shi-qie, YAN Jia-jun, HU Chao, LI Da-xu, YOU Ming-hong, ZHANG Yu, DAO Zhi-xue, ZHANG Chang-bing, and GAN You-min
AbstractSiberian wildrye (Elymus sibiricus L.) is one of the predominant pasture species in Qinghai-Tibet plateau of China.It supplies a large number of fodders to domestic animals in spring and winter,and provides a large proportion of the summer and autumn grazing in these alpine regions.Crude protein (CP),acid deterAbstractSiberian wildrye (Elymus sibiricus L.) is one of the predominant pasture species in Qinghai-Tibet plateau of China.It supplies a large number of fodders to domestic animals in spring and winter,and provides a large proportion of the summer and autumn grazing in these alpine regions.Crude protein (CP),acid detergent fiber (ADF),neutral detergent fiber (NDF) and in vitro dry matter digestibility (IVDMD) are the most important aspects of nutritive value of forages.A successful application of near infrared spectroscopy (NIRS) in combination with partial least square regression (PLSR) for the determination of four parameters (CP,ADF,NDF and IVDMD) of Siberian wildrye was developed.The standard errors of calibration (SEC,%DM) and R2cal values (in parentheses) were 0.329 9(0.994 5),0.779 9(0.949 9),1.343 0(0.913 3),and 1.376 2(0.982 2) for CP,ADF,NDF and IVDMD equations,respectively.The standard errors of prediction (SEP,%DM) and R2val values (in parentheses) were 0.362 1(0.993 8),0.787 8(0.944 9),1.385 2(0.890 7),and 1.430 3(0.979 0) for CP,ADF,NDF and IVDMD,respectively.A good correlation (r>0.943 8) was found between results from NIRS and the traditional chemical method,and residual predictive deviation (RPD) ranged from 3.02 to 12.63.It was concluded that NIR spectroscopic technique associated with chemometrics is sufficiently sensitive to allow the accurate prediction of the concentrations of components (CP,ADF and NDF) and IVDMD of Siberian wildrye..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2103 (2015)
Preparation of Rubber Accelerator Zinc Diethyldithiocarbamate and Its Spectral Analysis
ZHANG Zhi-liang, JIA Tai-xuan, JIANG Yue-hua, PENG Hong-yan, XU Guang-pu, and LI Hong-liang
In the study,rubber accelerator Zinc diethyldithiocarbamate (EZ) was synthesized firstly.Complex EZ of single crystal was cultivated by solvent evaporation method.EZ was detected and characterized by XRD single crystal diffraction,FTIR and TG-DSC.The micro-structure and intrinsic regularity were revealed.Its highly effIn the study,rubber accelerator Zinc diethyldithiocarbamate (EZ) was synthesized firstly.Complex EZ of single crystal was cultivated by solvent evaporation method.EZ was detected and characterized by XRD single crystal diffraction,FTIR and TG-DSC.The micro-structure and intrinsic regularity were revealed.Its highly efficient performance of rubber vulcanization promotion was decided due to its orientation structure?and high order.The result of TG-DSC showed that complex EZ was possessed with a little CS2.The chemical bond types in EZ were revealed by FTIR,the same as single crystal?diffraction testing by different way.The decomposition temperature of EZ was very high.It could provided reference with research on rubber vulcanizing properties by EZ on rubber vulcanizing machine.This study can help the enterprises to designate the working standard tracing detection of EZ industrialized production.Performance index of EZ was judged.The project of EZ industry standard can be declared by the enterprises,written a draft standard on the basis experimental data..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2108 (2015)
Bare Soil Moisture Inversion Model Based on Visible-Shortwave Infrared Reflectance
ZHENG Xiao-po, SUN Yue-jun, QIN Qi-ming, REN Hua-zhong, GAO Zhong-ling, WU Ling, MENG Qing-ye, WANG Jin-liang, and WANG Jian-hua
Soil is the loose solum of land surface that can support plants.It consists of minerals,organics,atmosphere,moisture,microbes,et al.Among its complex compositions,soil moisture varies greatly.Therefore,the fast and accurate inversion of soil moisture by using remote sensing is very crucial.In order to reduce the influeSoil is the loose solum of land surface that can support plants.It consists of minerals,organics,atmosphere,moisture,microbes,et al.Among its complex compositions,soil moisture varies greatly.Therefore,the fast and accurate inversion of soil moisture by using remote sensing is very crucial.In order to reduce the influence of soil type on the retrieval of soil moisture,this paper proposed a normalized spectral slope and absorption index named NSSAI to estimate soil moisture.The modeling of the new index contains several key steps:Firstly,soil samples with different moisture level were artificially prepared,and soil reflectance spectra was consequently measured using spectroradiometer produced by ASD Company.Secondly,the moisture absorption spectral feature located at shortwave wavelengths and the spectral slope of visible wavelengths were calculated after analyzing the regular spectral feature change patterns of different soil at different moisture conditions.Then advantages of the two features at reducing soil types’ effects was synthesized to build the NSSAI.Thirdly,a linear relationship between NSSAI and soil moisture was established.The result showed that NSSAI worked better (correlation coefficient is 0.93) than most of other traditional methods in soil moisture extraction.It can weaken the influences caused by soil types at different moisture levels and improve the bare soil moisture inversion accuracy..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2113 (2015)
NIR Assignment of Magnolol by 2D-COS Technology and Model Application Huoxiangzhengqi Oral Liduid
PEI Yan-ling, WU Zhi-sheng, SHI Xin-yuan, PAN Xiao-ning, PENG Yan-fang, and QIAO Yan-jiang
Near infrared (NIR) spectroscopy assignment of Magnolol was performed using deuterated chloroform solvent and two-dimensional correlation spectroscopy (2D-COS) technology.According to the synchronous spectra of deuterated chloroform solvent and Magnolol,1 365~1 455,1 600~1 720,2 000~2 181 and 2 275~2 465 nm were the chNear infrared (NIR) spectroscopy assignment of Magnolol was performed using deuterated chloroform solvent and two-dimensional correlation spectroscopy (2D-COS) technology.According to the synchronous spectra of deuterated chloroform solvent and Magnolol,1 365~1 455,1 600~1 720,2 000~2 181 and 2 275~2 465 nm were the characteristic absorption of Magnolol.Connected with the structure of Magnolol,1 440 nm was the stretching vibration of phenolic group O—H,1 679 nm was the stretching vibration of aryl and methyl which connected with aryl,2 117,2 304,2 339 and 2 370 nm were the combination of the stretching vibration,bending vibration and deformation vibration for aryl C—H,2 445 nm were the bending vibration of methyl which linked with aryl group,these bands attribut to the characteristics of Magnolol.Huoxiangzhengqi Oral Liduid was adopted to study the Magnolol,the characteristic band by spectral assignment and the band by interval Partial Least Squares (iPLS) and Synergy interval Partial Least Squares (SiPLS) were used to establish Partial Least Squares (PLS) quantitative model,the coefficient of determination R2cal and R2pre were greater than 0.99,the Root Mean of Square Error of Calibration (RMSEC),Root Mean of Square Error of Cross Validation (RMSECV) and Root Mean of Square Error of Prediction(RMSEP) were very small.It indicated that the characteristic band by spectral assignment has the same results with the Chemometrics in PLS model.It provided a reference for NIR spectral assignment of chemical compositions in Chinese Materia Medica,and the band filters of NIR were interpreted..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2119 (2015)
Progress in Application of Two-Dimensional Correlation Spectroscopy for Detection of Food Quality
Yang Renjie, Yang Yanrong, Liu Haixue, Dong Guimei, Du Yanhong, Shan Huiyong, and Zhang Weiyu
In recent years,the food safety and quality has always been a serious issue.Therefore,it is urgent to develop a rapid and widely available method to determine the quality of food.Due to high spectral resolution,good spectral selectivity and good ability of spectrogram analysis,the technology of two-dimensional(2D) corrIn recent years,the food safety and quality has always been a serious issue.Therefore,it is urgent to develop a rapid and widely available method to determine the quality of food.Due to high spectral resolution,good spectral selectivity and good ability of spectrogram analysis,the technology of two-dimensional(2D) correlation spectroscopy is an effective method for solving three major problems encountered by the conventional one-dimensional(1D) spectrum:low selectivity of the spectra,difficulty in extracting the information of the spectral feature and difficulty in spectrogram analysis.Therefore,2D correlation spectroscopy,which is suited to distinguish similar samples hardly distinguished by the conventional 1D spectroscopy,has been successfully applied in many complex biological systems.The developmental process,the experimental way to obtain spectrum,the fundamental mathematical principle and the properties of 2D correlation spectroscopy were introduced in this paper.At the same time,it is pointed out that the origin of weak characteristic bands of substance can be verified in terms of the positive or negative corss peaks in synchronous 2D correlation spectrum combined with the existence or inexistence of corss peaks in asynchronous 2D correlation spectrum The application of 2D near-infrared,mid-infrared,fluorescence,and raman correlation spectroscopy in the detection of food quality and adulteration,concentrated specifically on diary product,wine,oil,meat,honey,and rice were reviewed.Finally,the limitations and future development prospects were pointed out..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2124 (2015)
Advance of Development and Application of GC-IR Technology
HUANG Yi-fei, CAI Zan, HU Jing, LIN Li-qiong, XIAO Xiao-hua, and LI Gong-ke
The gas chromatograph (GC)-infrared spectroscopy (IR) technique combines the particular separating capacity of GC and the faultlessly with distinguishing capacity of molecular structure of IR,its detective sensitivity is very high and itis used to separate and identify many kinds of complicated compounds from element sThe gas chromatograph (GC)-infrared spectroscopy (IR) technique combines the particular separating capacity of GC and the faultlessly with distinguishing capacity of molecular structure of IR,its detective sensitivity is very high and itis used to separate and identify many kinds of complicated compounds from element speciation analysis,natural products,and gasoline.This paper introduces the principle of GC-IR.Three types of interface techniques,light pipe technique,matrix isolation technique and direct deposition technique are compared.Connection type with other detections and factors influencing sensitivity in interface are also introduced.The improvement and achievement in coupling GC system,interface,data processing techniques and its application is reviewed in the present paper..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2130 (2015)
Purity Detection Model Update of Maize Seeds Based on Active Learning
TANG Jin-ya, HUANG Min, and ZHU Qi-bing
Seed purity reflects the degree of seed varieties in typical consistent characteristics,so it is great important to improve the reliability and accuracy of seed purity detection to guarantee the quality of seeds.Hyperspectral imaging can reflect the internal and external characteristics of seeds at the same time,which Seed purity reflects the degree of seed varieties in typical consistent characteristics,so it is great important to improve the reliability and accuracy of seed purity detection to guarantee the quality of seeds.Hyperspectral imaging can reflect the internal and external characteristics of seeds at the same time,which has been widely used in nondestructive detection of agricultural products.The essence of nondestructive detection of agricultural products using hyperspectral imaging technique is to establish the mathematical model between the spectral information and the quality of agricultural products.Since the spectral information is easily affected by the sample growth environment,the stability and generalization of model would weaken when the test samples harvested from different origin and year.Active learning algorithm was investigated to add representative samples to expand the sample space for the original model,so as to implement the rapid update of the model’s ability.Random selection (RS) and Kennard- Stone algorithm (KS) were performed to compare the model update effect with active learning algorithm.The experimental results indicated that in the division of different proportion of sample set (1∶1,3∶1,4∶1),the updated purity detection model for maize seeds from 2010 year which was added 40 samples selected by active learning algorithm from 2011 year increased the prediction accuracy for 2011 new samples from 47%,33.75%,49% to 98.89%,98.33%,98.33%.For the updated purity detection model of 2011 year,its prediction accuracy for 2010 new samples increased by 50.83%,54.58%,53.75% to 94.57%,94.02%,94.57% after adding 56 new samples from 2010 year.Meanwhile the effect of model updated by active learning algorithm was better than that of RS and KS.Therefore,the update for purity detection model of maize seeds is feasible by active learning algorithm..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2136 (2015)
Detection of Adulteration in Milk Powder with Starch Near Infrared
WANG Ning-ning1, SHEN Bing-hui2, GUAN Jian-jun1, ZHAO Zhong-rui1, ZHU Ye-wei3, ZHANG Lu-da2, YAN Yan-lu4, ZHENG Yu-yan5, DONG Cheng-yu6, and KANG Ding-ming1
Three China trademarks of milk powder called Mengniu,Yili,Wandashan were taken as testing samples.Each of them mixed varied amount of starch in different gradient,which were consisted of 32 adulterated milk powder samples mixed with starch,was taken as standard samples for constructing predicted model.To those 32 samplThree China trademarks of milk powder called Mengniu,Yili,Wandashan were taken as testing samples.Each of them mixed varied amount of starch in different gradient,which were consisted of 32 adulterated milk powder samples mixed with starch,was taken as standard samples for constructing predicted model.To those 32 samples,the reflecting spectrum characteristics in middle wave of near infrared spectrum with Near Infrared Spectrum Analyzer (Micro NIR 1700) produced by JDSU Ltd.USA were collected for five repeats in five different days.The time span was nearly two months.Firstly,we build the model used the reflecting spectrum characteristics of those samples with biomimetic pattern recognition (BPR) arithmetic to do the qualitative analysis.The analysis included the reliability of testing result and stability of the model.When we took ninety percent as the evaluation threshold of testing result of CAR(Correct Acceptance Rate)and CRR (Correct Rejection Rate),the lowest starch content of adulterate milk powder in all tested samples which the tested result were bigger than that abovementioned threshold was designated CAR threshold (CAR-T) and CRR threshold (CRR-T).CAR means the correct rate of accepting a sample which is belong to itself,CRR means correct rate of refusing to accept a sample which is not belong to itself.The results were shown that,when we constructed a model based on the near infrared spectrum data from each of three China trademark milk powders,respectively,if we constructed a model with infrared spectrum data tested in a same day,both the CAR-T and CRR-T of adulterate starch content of a sample can reach 0.1% in predicting the remainder infrared spectrum data tested within a same day.The three China trademarks of milk powder had the same result.In addition,when we ignored the trademarks,put the spectrum data of adulterate milk powder samples mixed with the same content of starch of three China trademarks milk powder together to construct a model,the CAR-T of mixed starch content of a sample may reach 0.1%,the CRR-T can reach 1%,if the model construction and predicting were performed with near infrared spectrum data tested in a same day.However,the CAR-T can just stably reach up to 5% and the CRR-T have the same result,if the model construction and predicting were crossly performed with mixed near infrared spectrum data tested in different days.Furthermore,the correct recognizing threshold mixed starch of a sample can stably reach up to 1% and the CAR-T can reach 5%,if the model construction was based on near infrared spectrum data combined the previous four days to predict the output of the another day.On the other hand,we also engaged quantitative analysis to the starch content in milk power with two kinds of arithmetic (PLSR,LS-SVR).In contrast with the testing outputs,the reliability of both the CAR-T and CRR-T in qualitative analysis was further validated..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2141 (2015)
Comparison of Three Spectroscopies for the Determination of Composition of LDPE/PP Blend with Partial Least-Squares
CHEN Ru-huang, and JIN Gang
This paper presented an application of mid-infrared (MIR),near-infrared (NIR) and Raman spectroscopies for collecting the spectra of 31 kinds of low density polyethylene/polyprolene (LDPE/PP) samples with different proportions.The different pre-processing methods (multiplicative scatter correction,mean centering and SaThis paper presented an application of mid-infrared (MIR),near-infrared (NIR) and Raman spectroscopies for collecting the spectra of 31 kinds of low density polyethylene/polyprolene (LDPE/PP) samples with different proportions.The different pre-processing methods (multiplicative scatter correction,mean centering and Savitzky-Golay first derivative) and spectral region were explored to develop partial least-squares (PLS) model for LDPE,their influence on the accuracy of PLS model also being discussed.Three spectroscopies were compared about the accuracy of quantitative measurement.Consequently,the pre-processing methods and spectral region have a great impact on the accuracy of PLS model,especially the spectra with subtle difference,random noise and baseline variation.After being pre-processed and spectral region selected,the calibration model of MIR,NIR and Raman exhibited R2/RMSEC values of 0.990 6/2.941,0.997 3/1.561 and 0.997 2/1.598 respectively,which corrsponding to 0.887 6/10.15,0.849 3/11.75 and 0.875 7/10.67 before any treatment.The results also suggested MIR,NIR and Raman are three strong tools to predict the content of LDPE in LDPE/PP blend.However,NIR and Raman showed higher accuracy after being pre-processed and more suitability to fast quantitative characterization due to their high measuring speed..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2147 (2015)
Prediction the Soluble Solid Content in Sugarcanes by Using Near Infrared Hyperspectral Iimaging System
GAO Jun-feng, ZHANG Chu, XIE Chuan-qi, ZHU Feng-le, GUO Zhen-hao, and HE Yong
In order to explore the feasibility of prediction soluble solid contents (SSC) in sugarcane stalks by using near infrared hyperspectral imaging techniques,two hundred and forty sugarcane stalks which come from three different varieties were studied.After obtaining the raw hyperspectral images of sugarcane stalks,the spIn order to explore the feasibility of prediction soluble solid contents (SSC) in sugarcane stalks by using near infrared hyperspectral imaging techniques,two hundred and forty sugarcane stalks which come from three different varieties were studied.After obtaining the raw hyperspectral images of sugarcane stalks,the spectral information and textural features were discussed respectively.The prediction models were established by using partial least squares regression (PLSR),principal components regression (PCR) and least squares support vector machines (LS-SVM) algorithms.Besides,three different selected wavelengths algorithms such as successive projection (SPA) algorithms,intervals partial least squares (iPLS) algorithms and uninformation variables elimination (UVE) algorithm were analyzed after building partial least squares regression model.The results indicate that partial least squares regression model based on spectral features can be an steady model to predict SSC and the correlation coefficient (R2) of calibration sets and prediction sets are 0.879,0.843.The root mean square errors of calibration sets and prediction sets are 0.644,0.742 respectively.The obtained 105 wavelengths which were selected by UVE algorithm are effective spectral features.The R2 results of calibration sets and prediction sets of its PLSR model are 0.860,0.813.The root mean square errors of calibration sets and prediction sets are 0.693,0.810 respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2154 (2015)
Experimental Investigation of Infrared Spectral Emissivity of Copper at 300~1 123 K
ZHANG Kai-hua, YU Kun, ZHANG Feng, and LIU Yu-fang
In this study,a new reflective experimental apparatus,which can measure the spectral emissivity of opaque materials accurately and real timely,has been developed based on the Kirchhoff’s law by using the GaAs semiconductor laser as the standard radiation source.The spectral emissivity of brass and red copper at wavelenIn this study,a new reflective experimental apparatus,which can measure the spectral emissivity of opaque materials accurately and real timely,has been developed based on the Kirchhoff’s law by using the GaAs semiconductor laser as the standard radiation source.The spectral emissivity of brass and red copper at wavelength λ=1.55 μm were investigated systematically with the temperatures range from 300 up to 1 123 K by using this apparatus and the influence of temperature,oxidation and heating time on the spectral emissivity of two kinds of specimens were also discussed.The experimental data showed that the spectral emissivity increased with increase of temperature and appeared its peak value and valley value when the thickness of oxide film was at some degree.The spectral emissivity of red copper was always greater than that of brass.The formula for calculating the thickness of oxide film was derived from the reflection model composed of a metal and oxide film,then the peak and valley thickness of the red copper were estimated according to this model.The experimental data of constant temperature measurements showed that the spectral emissivity had a slight increase with heating time increasing.Two hours later,the spectral emissivity of two kinds of samples trended to be stable when the thickness of oxide film was at some degree.The values of spectral emissivity at high temperatures were always larger than that of low temperatures.The results of this study will further enrich spectral emissivity data of copper and provide experimental basis for its application..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2159 (2015)
Infrared Spectral Characteristics of Ambers from Three Main Sources (Baltic,Dominica and Myanmar)
WANG Yan, SHI Guang-hai, SHI Wei, and WU Rui-hua
Infrared spectra of ambers from Baltic,Dominica and Myanmar are obtained by Specular Reflection and KBr Pellet Transmission Methods.Although the infrared spectra of these ambers present similar features for ambers from different locations,refined differences in location and intensity of absorption peaks could be identiInfrared spectra of ambers from Baltic,Dominica and Myanmar are obtained by Specular Reflection and KBr Pellet Transmission Methods.Although the infrared spectra of these ambers present similar features for ambers from different locations,refined differences in location and intensity of absorption peaks could be identified among them.Between 3 000 and 2 800 cm-1,two obvious bands with a weak shoulder peak are seen in the Baltic amber spectrum,whereas there are two bands in the Dominica’s and three bands in the Myanmar’s.In region of 1 740~1 690 cm-1,one band appears at 1 732 cm-1 in the spectra of the Baltic amber sample,distinctly different from those of the Dominican and Myanmar ambers which have a doublet at 1 730 and 1 695 cm-1.For the Dominican amber,the intensity of 1 730 cm-1 is much stronger than that of 1 695 cm-1,being contrary to the spectra of the Myanmar amber,whose intensity of 1 730 cm-1 is weaker than that of 1 695 cm-1.Within region of 1 300~1 000 cm-1,Baltic amber can be distinguished from other two origin ambers by a horizontal shoulder,often called “Baltic shoulder”,with a definite band at 1 163 cm-1.Spectra of the Dominican amber show a unique band at 1 240 cm-1,while spectra of the Myanmar amber have a triplet at 1 224,1 130 or 1 154 cm-1 and 1 033 cm-1,like “ wave of mountain” altogether.Ratios of absorption intensity of 1 381 vs.1 456 cm-1 are about 0.9,0.8 and 0.7 respectively for the Baltic,Dominican and Myanmar ambers.These differences of absorption spectra could be used as the identifiable characteristics corresponding to the ambers locality.The correlation between the ambers’ infrared spectra and localities is probably due to their age,plant provenance and geological environment indivadually.On the basis of presence and intensity of the bands attributed to exocyclic methylene groups,it is suggested that the Myanmar amber formed earliest,followed by Baltic and then the youngest Dominican.These finding reveals that infrared spectroscopy may have significance for identifing amber locality,and thus potentially have archeological implications in determining source of some ancient ambers..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2164 (2015)
A Modified Procedure to Isolate Synchronous Cells from Yyeasts with Continuous Percoll Density Gradient and Their Raman Discri Mination
HUANG Shu-shi, LAI Jun-zhuo, LU Ming-qian, CHENG Qin, LIAO Wei, and CHEN Li-mei
A modified procedure of Percoll density gradient centrifugation was developed to isolate and fractionate synchronous cells from stationary phase (sp) cultures of different yeast strains,as well as Raman spectra discrimination of single yeast cells was reported.About 1.75 mL Percoll solution in 2 mL polypropylene centriA modified procedure of Percoll density gradient centrifugation was developed to isolate and fractionate synchronous cells from stationary phase (sp) cultures of different yeast strains,as well as Raman spectra discrimination of single yeast cells was reported.About 1.75 mL Percoll solution in 2 mL polypropylene centrifugal tube was centrifuged at 19 320 g,20 ℃ with an angle rotor for 15 min to form continuous densities gradient (1.00~1.31 g·mL-1),approximately 100 μＬ sample was overlaid onto the preformed continuous density gradient carefully,subsequently,centrifuged at 400 g for 60 min in a tabletop centrifuge equipped with a angle rotor at 25 ℃.Yeast samples could be observed that the suspensions were separated into two cell fractions obviously.Both fractions of different yeast strains were respectively determined by differential interference contrast (DIC),phase contrast microscope and synchronous culture to distinguish their morphological and growth trait.The results showed that the lower fraction cells were unbudded,mostly unicellular,highly refractive,homogeneous and uniform in size,and represented growth characteristic synchronously;Their protoplasm had relatively high density,and contained significant concentrations of glycogen;all of which were accordant with description of quiescent yeast cells and G0 cells in previously published paper.It was shown that lower fraction was quiescent cells,synchronous G0 cells as well.A Raman tweezers setup was used to investigate the differences between two fractions,G0 cells and non G0 cells,at a single cell level.The result showed that both G0 cells and the non G0 cells had the same characteristic peaks corresponding biological macromolecules including proteins,carbohydrates and nucleic acids,but all characteristic peak intensities of G0 cells were higher than that of non G0 cells,implied that the macromolecular substance content of G0 cells was more higher.Principal component analysis (PCA) was performed between G0 cells and non G0 cells,the results showed that the chemical composition content among the synchronization G0 cells has less difference,and G0 cells were homogeneous but non G0 cells were heterogeneous,indicating single cell optical tweezers Raman spectroscopy could identify the synchronous and asynchronous cells.The modified method is feasible,economical and efficient highly.G0 synchronous cells of most yeast strains could be isolated by a modification of Percoll density gradient centrifugation..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2170 (2015)
Study on the Effects of Ginsenoside Rb1 on DPPC Bilayers by Using Thermo-Raman Spectrum and DSC
HUI Ge, LIU Wei, ZHANG Jing-zhou, ZHOU Tie-li, WANG Si-ming, ZHAO Yu, and ZHAO Bing
The research on the interactions between Ginsenosides and biomembranes plays a crucial role in thorough understanding the pharmacological activity and biologyical effect of Chinese medicine Panax ginseng.With the bilayer structure,DPPC often serves as an simulation model of the cell membrane to study the role of drug mThe research on the interactions between Ginsenosides and biomembranes plays a crucial role in thorough understanding the pharmacological activity and biologyical effect of Chinese medicine Panax ginseng.With the bilayer structure,DPPC often serves as an simulation model of the cell membrane to study the role of drug molecules and cell membranes.Ginsenoside Rb1,one of the most important components of Panaxginseng,playing the significant roles of pharmacological effects and biological properties.Raman and differential scanning calorimetry(DSC) are respectively a powerful tool for discussing the molecular interaction,and a kind of general technology by which researching the bilayer monomer structures and its interactions with drug molecules.However,rarely research reports on the interactions between drug molecules and biomembranes by means of both technologies above.In this paper,the influence of ginsenoside monomer Rb1 on DPPC membrane bilayers was investigated by thermo-Raman and DSC.In Raman spectra,the changes of DPPC molecule have been observed before and after interacted with ginsenoside Rb1,the data analysis indicates three aspects:the O—C—C—N+ polar head group skeleton,C—C stretching vibration area,and the C—H bond stretching vibrarion in terminated methyl group of alkyl chains.The results showed that ginsenoside Rb1 molecule with certain concentration has not changed the gauche conformation of the polar head backbone group in DPPC bilayers,the order of the internal molecular chain and the lateral chain-chain packing have been decreased as the temperature increased,the lateral disposed disorder has been increased.The changes of some thermodynamic constants obtained by DSC experiment such as phase transition temperature (Tm)、the temperature at which the transition is half completed (ΔT1/2),and the transition enthalpy normalized per mol of DPPC (ΔH) have been showed further results of the thermo Raman experiments,with increasing the concentration of ginsenoside Rb1,the pre-transition temperature of DPPC bilayers dropped immediately with small amount of the Rb1 drug when the containtion was only 5 mol% and the whole system has been destructed at the same time,the main phase transition peak showed as a new little shoulder seam,however,both pre-and main transition peak disappeared completely until the drug concentration increased to 20 mol%,the phase transition temperature of DPPC has been reduced significantly,and the fluidity of bilayers has been increased.Both experiments indicated that the strong effects of ginsenoside Rb1 on DPPC..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2176 (2015)
Research on Identification and Determination of Pesticides in Apples Using Raman Spectroscopy
ZHAI Chen, PENG Yan-kun, LI Yong-yu, DHAKAL Sagar, XU Tian-feng, and GUO Lang-hua
Raman spectroscopy combined with chemometric methods has been thought to an efficient method for identification and determination of pesticide residues in fruits and vegetables.In the present research,a rapid and nondestructive method was proposed and testified based on self-developed Raman system for the identificatioRaman spectroscopy combined with chemometric methods has been thought to an efficient method for identification and determination of pesticide residues in fruits and vegetables.In the present research,a rapid and nondestructive method was proposed and testified based on self-developed Raman system for the identification and determination of deltamethrin and acetamiprid remaining in apple.The peaks of Raman spectra at 574 and 843 cm-1 can be used to identify deltamethrin and acetamiprid,respectively,the characteristic peaks of deltamethrin and acetamiprid were still visible when the concentrations of the two pesticides were 0.78 and 0.15 mg·kg-1 in apples samples,respectively.Calibration models of pesticide content were developed by partial least square (PLS) algorithm with different spectra pretreatment methods (Savitzky-Golay smoothing,first derivative transformation,second derivative transformation,baseline calibration,standard normal variable transformation).The baseline calibration methods by 8th order polynomial fitting gave the best results.For deltamethrin,the obtained prediction coefficient (Rp) value from PLS model for the results of prediction and gas chromatography measurement was 0.94;and the root mean square error of prediction (RMSEP) was 0.55 mg·kg-1.The values of Rp and RMSEP were respective 0.85 and 0.12 mg·kg-1 for acetamiprid.According to the detect performance,applying Raman technology in the nondestructive determination of pesticide residuals in apples is feasible.In consideration of that it needs no pretreatment before spectra collection and causes no damage to sample,this technology can be used in detection department,fruit and vegetable processing enterprises,supermarket,and vegetable market.The result of this research is promising for development of industrially feasible technology for rapid,nondestructive and real time detection of different types of pesticide with its concentration in apples.This supplies a rapid nondestructive and environmentally friendly way for the determination of fruit and vegetable quality and safety..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2180 (2015)
Study on Vibrational Spectra Characteristics of Gem-Quality Natrolite
LIU Xian-yu, SHEN Xi-tian, LU Ren, and ZHAO Shan-rong
Recently,there is a batch of colorless faceted gem-quality natrolite appear in the international jewelry market.In order to provide some information that can help us to distinguish them from the imitations.The infrared spectrometer and Raman spectrometer were employed to study the characteristics of the vibrational speRecently,there is a batch of colorless faceted gem-quality natrolite appear in the international jewelry market.In order to provide some information that can help us to distinguish them from the imitations.The infrared spectrometer and Raman spectrometer were employed to study the characteristics of the vibrational spectrum of three natrolite samples in this article.The typical infrared spectra shows that:the absorption region 4 000~1 200 cm-1 is induced by stretching vibration of the hydroxyl group,the strong absorption peaks range from 1 200~600 cm-1 are relative with the anti-symmetry and symmetry stretching vibration of tetrahedral T—O bonds (T=Si or Al).The Raman spectra scattering peaks are located in the range of 300~600 and 700~1 200 cm-1.The low intensity Raman scattering spectrum in the range of 300~360 cm-1 corresponds to the vibration of the water molecules in the crystal.The medium intensity Raman scattering spectrum is assigned to the deformation of SiO4 tetrahedra.The Raman spectra scattering peak at 726 cm-1 is assigned to the stretching vibration of Al—O;The Si—O stretching vibration displays the Raman spectra scattering peaks at 974,1 038 and 1 084 cm-1..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2186 (2015)
Study on Synthesis and Luminescence Mechanism of Novel Green Sr3Y(PO4)3:Ce3+,Tb3+ Phosphors
DONG Guo-shuai, LIU Hai-bo, LUO Li, and WANG Yin-hai
A novel green light-emitting phosphor Sr3Y(PO4)3Ce3+,Tb3+ was synthesized by the traditional high temperature solid state reaction method.Luminescence mechanism and crystal structure were investigated by X-Ray Diffraction (XRD) and photoluminescence spectra (PL).The XRD patterns demonstrate that the samples belong to tA novel green light-emitting phosphor Sr3Y(PO4)3Ce3+,Tb3+ was synthesized by the traditional high temperature solid state reaction method.Luminescence mechanism and crystal structure were investigated by X-Ray Diffraction (XRD) and photoluminescence spectra (PL).The XRD patterns demonstrate that the samples belong to the single phase of Sr3Y(PO4)3 in experimental doping concentrations range.Obviously,the excitation band of Sr3Y(PO4)3∶Tb3+ and the emission of Sr3Y(PO4)3∶Ce3+ have a significant spectral overlap in the wavelength range of 330~380 nm,which implies the great possibility of an efficient ET from Ce3+ to Tb3+.Under the 315 nm ultraviolet excitation,a blue emission(320~420 nm)from Ce3+ and a yellowish-green emission(480~500,530~560 nm)from Tb3+ were obtained from Sr3Y(PO4)3∶Ce3+,Tb3+.When the Ce3+ concentration was 7%,the emission could be adjusted from blue to green region by tuning the Tb3+ doping concentrations from 1% to 50% through an energy transfer process.This text plot the schematic energy levels of Ce3+,and Tb3+ with electronic transitions and energy transfer processes in Sr3Y(PO4)3∶Ce3+,Tb3+,which disclose the electron motion processes of Sr3Y(PO4)3∶Ce3+,Tb3+.From the dependence of relative emission intensity of Ce3+,Tb3+ (5D4→7Fj)and ET efficiency from Ce3+ to Tb3+ on the concentrations of Tb3+,It can be seen that the relative intensity of Tb3+ and the values of ηET increase gradually with the increasing of Tb3+ as well as the relative intensity of Ce3+ decreases remarkably.The largest energy transfer efficiency reaches as high as 80% when the concentration of Tb3+ was 50%,demonstrating the efficient energy transfer from Ce3+ to Tb3+.The CIE chromaticity coordinate positions are plotted,as can be seen the emitting color of Ce3+ and Tb3+ singly doped Sr3Y(PO4)3∶Ce3+,Tb3+ phosphor are blue and yellowish green,respectively.The emitting color of samples Sr3Y(PO4)3∶Ce3+,Tb3+ changes from blue region to green region with the rising doping contents of Tb3+.Sr3Y(PO4)3∶Ce3+ and Tb3+ phosphor can be used as a green light-emitting phosphor in white LED devices and LCD backlights..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2189 (2015)
Photosynthetic Parameters Inversion Algorithm Study Based on Chlorophyll Fluorescence Induction Kinetics Curve
QIU Xiao-han, ZHANG Yu-jun, YIN Gao-fang, SHI Chao-yi, YU Xiao-ya, ZHAO Nan-jing, and LIU Wen-qing
The fast chlorophyll fluorescence induction curve contains rich information of photosynthesis.It can reflect various information of vegetation,such as,the survival status,the pathological condition and the physiology trends under the stress state.Through the acquisition of algae fluorescence and induced optical signal,The fast chlorophyll fluorescence induction curve contains rich information of photosynthesis.It can reflect various information of vegetation,such as,the survival status,the pathological condition and the physiology trends under the stress state.Through the acquisition of algae fluorescence and induced optical signal,the fast phase of chlorophyll fluorescence kinetics curve was fitted.Based on least square fitting method,we introduced adaptive minimum error approaching method for fast multivariate nonlinear regression fitting toward chlorophyll fluorescence kinetics curve.We realized Fo (fixedfluorescent),Fm (maximum fluorescence yield),σPSII (PSII functional absorption cross section) details parameters inversion and the photosynthetic parameters inversion of Chlorella pyrenoidosa.And we also studied physiological variation of Chlorella pyrenoidosa under the stress of Cu2+..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2194 (2015)
Planktonic Algae’s Distribution and Correlation with Dissolved Organic Matters’ Fluorescence in the End of the Three Gorges Reservoir’s Back Water Zone
FAN Lei-lei, LI Si, YU Dan-ni, HE Qiang, JI Fang-ying, JIANG Zhong-yuan, GAO Zhi-xi, and AO Ke-hou
For researching the community structure,composition,and distribution of the planktonic algae in the Three Gorges Reservoir(TRG),especially,within TRG water levels’ fluctuating,mpacting to water quality with the algae’s growing,6 sampling cites in the end of the TGR’s back water zone,from Chaotianmen to Taihonggang TownFor researching the community structure,composition,and distribution of the planktonic algae in the Three Gorges Reservoir(TRG),especially,within TRG water levels’ fluctuating,mpacting to water quality with the algae’s growing,6 sampling cites in the end of the TGR’s back water zone,from Chaotianmen to Taihonggang Town,are chosen to monitor,at the sensitive stages time of algal bloom between March to May 2012,namely,water levels lowing from the highest impounding.the community’s structure,composition,and distribution of the planktonic algae in the TGR,and the correlation of water quality parameters and DOM’s fluorescence features with algae density,are obtained.According to the experimental results,blue algae fibre,chlorella,melosira,navicula are the dominated algae in the end of the TGR’s back water zone,from Chaotianmen to Taihonggang Town,algae density are 0.40~0.56×106,1.9~0.8×106,0.36~0.25×106,0.42~0.15×106 cells·L-1 respectively.Besides,anabaena,phormidium,cladophora,feather,ovate algae are existing in only limited 2 sections.The fitting results reveal obvious linear correlation of the EEM characteristics of DOM with the 4 kinds of dominated algal density,which could be useful conference for the algae bloom monitor,conveniently and effectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2198 (2015)
Sensitive Determination of Chondroitin Sulfate by Fluorescence Recovery of an Anionic Aluminum Phthalocyanine-Cationic Surfactant Ion-Association Complex Used as a Fluorescent Probe Emitting at Red Region
CHEN Lin, HUANG Ping, YANG Hui-qing, DENG Ya-bin, GUO Meng-lin, and LI Dong-hui
Determination of chondroitin sulfate in the biomedical field has an important value.The conventional methods for the assay of chondroitin sulfate are still unsatisfactory in sensitivity,selectivity or simplicity.This work aimed at developing a novel method for sensitive and selective determination of chondroitin sulfatDetermination of chondroitin sulfate in the biomedical field has an important value.The conventional methods for the assay of chondroitin sulfate are still unsatisfactory in sensitivity,selectivity or simplicity.This work aimed at developing a novel method for sensitive and selective determination of chondroitin sulfate by fluorimetry.We found that some kinds of cationic surfactants have the ability to quench the fluorescence of tetrasulfonated aluminum phthalocyanine (AlS4Pc),a strongly fluorescent compound which emits at red region,with high efficiency.But,the fluorescence of the above-mentioned fluorescence quenching system recovered significantly when chondroitin sulfate (CS) exits.Tetradecyl dimethyl benzyl ammonium chloride(TDBAC)which was screened from all of the candidates of cationic surfactants was chosen as the quencher because it shows the most efficient quenching effect.It was found that the fluorescence of AlS4Pc was extremely quenched by TDBAC because of the formation of association complex between AlS4Pc and TDBAC.Fluorescence of the association complex recovered dramatically after the addition of chondroitin sulfate (CS) due to the ability of chondroitin sulfate to shift the association equilibrium of the association,leading to the release of AlS4Pc,thus resulting in an increase in the fluorescence of the reaction system.Based on this phenomenon,a novel method with simplicity,accuracy and sensitivity was developed for quantitative determination of CS.Factors including the reaction time,influencing factors and the effect of coexisting substances were investigated and discussed.Under optimum conditions the linear range of the calibration curve was 0.20~10.0μg·mL-1.The detection limit for CS was 0.070 μg·mL-1.The method has been applied to the analysis of practical samples with satisfied results.This work expands the applications of AlS4Pc in biomedical area..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2203 (2015)
Lanthanum Coordination Polymer Based on Benzimidazole-Dicarboxylic Acid and Phenanthroline:Crystal Structure,Fluorescence and Fluorescent Sensing for Organic Small Molecules
DONG Gao-yun, MA Xue, LI Jia-jia, and LI Xia
Two new complexes,{［Eu3(bidc)4(phen)2(NO3)］·2H2O}n(1) and ［Tb2(bidc)3(H2O)2］(2)(bidc=benzimidazole-dicarboxylate,phen=1,10-phenanthrolIne) were synthesized.Complex 1 shows 1D chain structure.The asymmetric unit of 1 contains three crystallographically different Eu3+,Eu (1)O6N2,Eu(2)O8 and Eu(3)O6N2.Complex 2 reveaTwo new complexes,{［Eu3(bidc)4(phen)2(NO3)］·2H2O}n(1) and ［Tb2(bidc)3(H2O)2］(2)(bidc=benzimidazole-dicarboxylate,phen=1,10-phenanthrolIne) were synthesized.Complex 1 shows 1D chain structure.The asymmetric unit of 1 contains three crystallographically different Eu3+,Eu (1)O6N2,Eu(2)O8 and Eu(3)O6N2.Complex 2 reveals 2D structure.It contains two crystallographically similar Tb3+,Tb(1)O8 and Tb(2)O8.Complex 1 displays the emission peaks at 581,593,615,654 and 702 nm,corresponding to the 5D0→7FJ (J=0－4) transitions of Eu3+.The most intense emission at 615 nm is attributed to the 5D0→7F2 transition,implies a red emission light of 1.The intensity rations I(5D0/7F2)/I(5D0/7F1) is about 2.5,indicating the chemical environment around Eu3+ does not have an inversion center.Complex 2 exhibits four emission peaks at 492,545,584 and 622 nm,corresponding to the 5D4→7FJ(J=6－3) transitions of Tb3+.The emission band at 545 nm corresponds to the 5D4→7F5 transition of the Tb3+,which gives an intense green luminescence output for the solid sample.Notably,the solvent-dependent luminescence behavior of complexes 1 and 2 was discussed.They show highly selective for nitrobenzene via a fluorescence quenching mechanism.The highly selective and sensitive sensing nitrobenzene leads to its application in environmental system..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2208 (2015)
Excitation-Emission Matrix Fluorescence Spectra Characteristics of DOM in a Combined Constructed Wetland
Lv Jing-jing, ZHANG Lie-yu, XI Bei-dou, HOU Li-an, and LI Ming
Using three-dimensional fluorescence technology,we studied fluorescent characteristics of two polluted rivers by a surface flow+vertical flow combined constructed wetlands of dissolving organic matter.The results showed that (1) the main sources of water-soluble humic organic matter in constructed wetland was biologicaUsing three-dimensional fluorescence technology,we studied fluorescent characteristics of two polluted rivers by a surface flow+vertical flow combined constructed wetlands of dissolving organic matter.The results showed that (1) the main sources of water-soluble humic organic matter in constructed wetland was biological metabolic input instead of terrigenous input; (2) in the later section of the surface flow constructed wetland,part of proteinoid substance changed into fulvic acid-like substance,which showed that the composition of dissolved organic matter and material structure tended to be stable after surface flow combined constructed wetland treatment; (3) it was of great significance that surface flow constructed wetland in structure transformation of water soluble organic matter,which could significantly improve the stability of water soluble organic matter.Surface flow+vertical flow combined constructed wetland process of dissolved organic matter had a good removal effect..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2212 (2015)
Determination of H2S in Rat Intestinal Perfusion Solution Based on Fluorescence Analysis
HOU Jun-feng, LI Xin-xia, SHEN Xue-ru, Miliban Huojia, and GUAN Ming
Under alkaline conditions,Fluorescein mercury has strong fluorescence,however,when it met S2-,its fluorescence would quench,in view of the above,a fluorescence method for determination of H2S in biological samples was established.In the 0.1 mol·L-1 NaOH dilution,when the concentration of fluorescein Mercury and NaUnder alkaline conditions,Fluorescein mercury has strong fluorescence,however,when it met S2-,its fluorescence would quench,in view of the above,a fluorescence method for determination of H2S in biological samples was established.In the 0.1 mol·L-1 NaOH dilution,when the concentration of fluorescein Mercury and Na2S was 5.0×10-5 and 1.0×10-5 mol·L-1 respectively,the fluorescence intensity of system was determined at 522 nm.The results showed that,at the range of 4.0×10-7~2.0×10-6 mol·L-1,the concentration decreasing of H2S and fluorescence intensity had good linear relationship,r=0.998 0,the RSD of precision test was 4.59% (n=7),the detection limit was 3.5×10-8 mol·L-1,the content of H2S in the sample were 1.01×10-6 and 1.15×10-6 mol·L-1,and the recovery rate was 95.8%~101.0%,the method has the advantages of simple operation,high sensitivity,good selectivity,can accurately determine of H2S in intestinal perfused solution,and provides the basis for the determination of endogenous H2S..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2217 (2015)
Authentication of Age of Bloodstains Using UV Visible Reflection Spectrum
GAO Qian-yu, and GAO Shi-ming
The age of bloodstains is tightly related to the time elapsed since the crime was committed.The inference of the time that the crime was committed is of great significance to solve the case,and it was also a difficult problem in judicial authentication.Therefore,establishing a method of rapid determination of bleeding The age of bloodstains is tightly related to the time elapsed since the crime was committed.The inference of the time that the crime was committed is of great significance to solve the case,and it was also a difficult problem in judicial authentication.Therefore,establishing a method of rapid determination of bleeding time is very necessary.Using a UV-visible spectrometer with a reflection accessory called ISR-240A and whiteboard as a reference standard,the reflection spectra of blood gauze,aluminum,glass and plastic were measured every hour under the condition of 16 ℃ and 70% humidity within 8 hours.Using SPSS to process the data,R541/R577 was figured out and linear fitting was completed.The same method was carried on on the gauze of blood at 24 ℃.The results showed that,within 8 hours,spectral reflectance values of blood at 541 and 577 nm increased gradually with the passage of injury time.In addition to the R2 of the glass with blood is 0.769,the rest of the R2 were greater than 0.900.The values of F were greater than F0.05(1,6)=5.59.Therefore,the linear regression model is significant meaningful.The method of using a UV-Visible spectrometer without doing any operations of the test samples is simple.Moreover,it does no harm to the further inspection in aspects of personal information,which is suitable for the judicial practice..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2221 (2015)
Study on the Character Relationship Between the Density and Susceptibility of the Rock and the Reflection Spectrum
XU Meng-long, YANG Chang-bao, LIU Wan-song, WU Yan-gang, and ZHANG Chen-xi
It chooses 15 kinds of rock from the three major rock categories as the rock samples (the number of rock samples is 208) and obtains the density,susceptibility and reflection spectrum at the wave band of 350~2 500 nm.It calculates the correlative coefficients with the aim of studying the characteristic relationship betIt chooses 15 kinds of rock from the three major rock categories as the rock samples (the number of rock samples is 208) and obtains the density,susceptibility and reflection spectrum at the wave band of 350~2 500 nm.It calculates the correlative coefficients with the aim of studying the characteristic relationship between the property (including the density and the susceptibility) of the rock and the reflectivity.It concludes the wave band of the reflection spectrum which owes the prospect to discuss the density and susceptibility of the rock qualitatively or quantitatively,meanwhile,it sums up the characteristic of the curves of the correlative coefficients.In this paper,the discussion and analysis based on the results show that the study on the character relationship between the property of rock (density and susceptibility) and the reflection spectrum is meaningful and workable..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2225 (2015)
Spectral Study on the Effects of Angle-Tuned Filter Wedge Angle Parameter to Reflecting Characteristics
YU Kan, HUANG De-xiu, YIN Juan-juan, and BAO Jia-qi
Three-port tunable optical filter is a key device in the all-optic intelligent switching network and dense wavelength division multiplexing system.The characteristics of the reflecting spectrum,especially the reflectivity and the isolation degree are very important to the three-port filter.Angle-tuned thin film filter Three-port tunable optical filter is a key device in the all-optic intelligent switching network and dense wavelength division multiplexing system.The characteristics of the reflecting spectrum,especially the reflectivity and the isolation degree are very important to the three-port filter.Angle-tuned thin film filter is widely used as a three-port tunable filter for its high rectangular degree and good temperature stability.The characteristics of the reflecting spectrum are greatly influenced not only by the incident angle,but also by the wedge angle parameter of the non-paralleled wedge thin film filter.In the present paper,the influences of the wedge angle parameter to the reflectivity and the half bandwidth are analyzed,and the reflecting spectrum characterstics are simulationed in different wedge angle parameter and polarity.The wedge angle-tuned thin film filter with 0.8° wedge angle parameter is fabricated.The experimental results show that keeping the wedge angle the same orientation to the incident angle will worsen the reflectivity and the rectangular degree of the reflecting spectrum.However,keeping the wedge angle orientation reverse to the incident angle will enhance the reflectivity and decrease the bandwidth,which will give higher reflectivity and isolation degree to the three-port filter than that of high parallel degree angle-tuned thin film filter..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2231 (2015)
Modeling Soil Spectral Reflectance with Different Mass Moisture Content
SUN Yue-jun, ZHENG Xiao-po, QIN Qi-ming, MENG Qing-ye, GAO Zhong-ling, REN Hua-zhong, WU Ling, WANG Jun, and WANG Jian-hua
The spatio-temporal distribution and variation of soil moisture content have a significant impact on soil temperature,heat balance between land and atmosphere and atmospheric circulation.Hence,it is of great significance to monitor the soil moisture content dynamically at a large scale and to acquire its continuous chaThe spatio-temporal distribution and variation of soil moisture content have a significant impact on soil temperature,heat balance between land and atmosphere and atmospheric circulation.Hence,it is of great significance to monitor the soil moisture content dynamically at a large scale and to acquire its continuous change during a certain period of time.The object of this paper is to explore the relationship between the mass moisture content of soil and soil spectrum.This was accomplished by building a spectral simulation model of soil with different mass moisture content using hyperspectral remote sensing data.The spectra of soil samples of 8 sampling sites in Beijing were obtained using ASD Field Spectrometer.Their mass moisture contents were measured using oven drying method.Spectra of two soil samples under different mass moisture content were used to construct soil spectral simulation model,and the model was validated using spectra of the other six soil samples.The results show that the accuracy of the model is higher when the mass water content of soil is below field capacity.At last,we used the spectra of three sampling points on campus of Peking University to test the model,and the minimum value of root mean square error between simulated and measured spectral reflectance was 0.005 8.Therefore the model is expected to perform well in simulating the spectrum reflectance of different types of soil when mass water content below field capacity..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2236 (2015)
On the Tributylphosphate-Based Super-Concentrated HCl System
GUO Lin, HUANG Kun, GUO Ran, HE An-qi, WENG Shi-fu, YANG Zhan-lan, ZHAO Ying, XIA Jin-ming, XU Yi-zhuang, KANG Ting-guo, and WU Jin-guang
We reported a new super-concentrated hydrochloric acid system prepared by using tri-n-butyl phosphate (TBP)-constructed reversed micelles at ambient temperature and pressure.According to the titration result,the molar ratio of H+ to H2O (denoted as nH+/nH2O) in the super-concentrated HCl range from 0.50 to 1.50 which aWe reported a new super-concentrated hydrochloric acid system prepared by using tri-n-butyl phosphate (TBP)-constructed reversed micelles at ambient temperature and pressure.According to the titration result,the molar ratio of H+ to H2O (denoted as nH+/nH2O) in the super-concentrated HCl range from 0.50 to 1.50 which are higher than that in saturated aqueous HCl bulk solution (0.28).Significant a moment of hydrochloric acid is confined in W/O reversed micelles.Therefore,the behavior and status of HCl are different from those of conventional bluk solution.FTIR spectroscopic results demonstrate that a significant amount of HCl remains in the molecular form rather than being ionized into H+ and Cl－.Thus,super-concentrated HCl provides an extraordinary chemical environment which may have significant influence on certain substances.We found that the color of the solution is reddish brown when copper ion is dissolved in super-concentrated HCl,while the color of the saturated HCl aqueous solution (37 Wt%) containing copper ion is green.That is to say,the copper ions exist in a special state under the unique chemical environment of super-concentrated HCl.UV-Vis-NIR spectra indicate that both d-d transition band and charge transfer transition band of copper ions in super-concentrated HCl solution underwent significant variations.In addition,copper ions also have obvious influence on the hydrogen bond network among HCl in the super-concentrated HCl solution.Remarkable variation is introduced in the H—Cl stretching band in FTIR spectra..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2241 (2015)
Changes of Forest Canopy Spectral Reflectance with Seasons in Lang Ya Mountains
LI Wei-tao, PENG Dao-li, ZHANG Yan, WU Jian, and CHEN Tai-sheng
The physiological mechanism and ecological structure of forest trees can change with the changes of years.In a certain extent,the changes were expressed through the canopy spectral features.The mastery of changing rules about spectral characteristics of trees over the years is benefit to remote sensing interpretation aThe physiological mechanism and ecological structure of forest trees can change with the changes of years.In a certain extent,the changes were expressed through the canopy spectral features.The mastery of changing rules about spectral characteristics of trees over the years is benefit to remote sensing interpretation and provide scientific basis for the classification of different trees.The study adopted high-resolution spectrometer to measure the canopy spectral characteristics for seven major deciduous trees and seven evergreen trees to gain the spectrum curve of four different ages and calculate the first derivative curve.The analysis of changing rules about spectral characteristics of different deciduous trees and evergreen trees and the comparison of changes about spectrum of various trees in the visible and infrared band could find the best year and best band for identification of trees.The results showed that the canopy spectral reflectance of deciduous and evergreen trees increases with the increase of age.And the spectral changes of two species were most obvious in the near infrared band..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2246 (2015)
MAX-DOAS Tomography Reconstruction for Gas Plume
WEI Min-hong, TONG Min-ming, LI Su-wen, and XIAO Jian-yu
In order to achieve precisely two-dimensional spatial distribution reconstruction of smoke plume,passive MAX-DOAS tomography is established,the measurement of the spatial distribution of the exhaust plume is implemented by more passive multi-axis differential absorption spectrum system.First,the multi-axis differentialIn order to achieve precisely two-dimensional spatial distribution reconstruction of smoke plume,passive MAX-DOAS tomography is established,the measurement of the spatial distribution of the exhaust plume is implemented by more passive multi-axis differential absorption spectrum system.First,the multi-axis differential absorption spectrum system and its mechanism of inverse gas concentration are introduced in the paper.Then,algebra iterative algorithm is adopted to extract the information of the trace gas concentration in reconstruction simulation with different models and different scanning optical path,and the reconstruction program is designed.Then,the numerical simulation results are compared.Finally,a platform of multi-axis differential absorption optical tomography system is set up,a field campaign was carried out.The numerical simulation results show that the MAX-DOAS tomography can accurately reconstruct two-dimensional spatial distribution of plume model,the reconstruction error of MAX-DOAS tomography with four light sources is about a third of the reconstruction error with double light sources,moreover,the reconstruction time is about a quarter of the reconstruction time of double light sources,and the reconstruction error of the twin peaks model is greater than that of the one peak model.Field test results show that the integral data of reconstruction image is consistent with the measured projection data of multi-axis differential absorption spectrum,the spatial distribution reconstruction of plume is in line with the actual situation.Studies have shown that the result of numerical simulation and field test results have consistency..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2252 (2015)
Components of Urinary Nanocrystals and Their Influence on Formation of Calcium Oxalate Stones
LI Yu-bao, WEN Xiao-ling, XUE Jun-fa, and OUYANG Jian-ming
High-resolution transmission electron microscopy,X-ray diffraction,selected area electron diffraction (SAED),and energy dispersive spectroscopy (EDS) were accurately performed to analyze the components of nanocrystals in the urine of patients with calcium oxalate (CaOx) stones.XRD,SAED and FFT detected the presence of High-resolution transmission electron microscopy,X-ray diffraction,selected area electron diffraction (SAED),and energy dispersive spectroscopy (EDS) were accurately performed to analyze the components of nanocrystals in the urine of patients with calcium oxalate (CaOx) stones.XRD,SAED and FFT detected the presence of calcium oxalate monohydrate (COM),uric acid (UA),and calcium phosphate (CaP).EDS detected the elements of C,O,Ca,with a small amount of N and P.These results showed that the main components of urinary nanocrystals were COM,with a small amount UA and phosphate.HRTEM observation showed that the particle size of urinary nanocrystals was dozens of nanometers.The result was consistent with the calculation by Debye-Scherrer equation.When the urine was filtered through a microporous membrane of 0.45,1.2,and 3 μm,respectively,the number of diffraction peaks of the obtained urine crystallites increased with the increased pore size,indicating the increase of urinary crystallite species.Crystal nucleation,growth,aggregation,and adhesion of crystals to the renal epithelial cells are important processes for CaOx stone formation.The presence of a large amount of COM crystals in patients’ urine is a critical factor for CaOx stones formation.Nano UA and CaP crystallite can induce the CaOx stone formation as central nidus..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2257 (2015)
A Method for Retrieving Thermospheric O/N2 from Measurements of OI130.4nm Dayglow
WANG Jing, TANG Yi, NAN Yi-bing, and NI Guo-qiang
Thermospheric O/N2 can be retrieved from the radiance of OI 130.4 nm dayglow.In the paper,the algebraic relationship between the two variables is established,and the characteristics of the radiance varying with observing angle and solar zenith angles are discussed,based on which the look-up tables of the regularizationThermospheric O/N2 can be retrieved from the radiance of OI 130.4 nm dayglow.In the paper,the algebraic relationship between the two variables is established,and the characteristics of the radiance varying with observing angle and solar zenith angles are discussed,based on which the look-up tables of the regularization factors are made up,thus putting up a method for retrieving thermospheric O/N2 from measurements of OI 130.4 nm dayglow and meanwhile introducing a correcting coefficient in the algorithm to dismiss the error brought about by the difference between the ideal atmosphere representative by NRLMSISE-00 and the real atmosphere.Finally,the simulated dayglow radiance data of Oct 1,2002 are used as an example to testify the validation of the algorithm.The results demonstrated that the algorithm is able to reconstruct most of the features of O/N2 and has an obvious advantage over the conventional algorithm..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2263 (2015)
Influence of the Composition of the Initial Mixtures on the Physicochemical and Biological Properties and Spectral Characteristics of Composts
SONG Cai-hong, LI Ming-xiao, WEI Zi-min, XI Bei-dou, ZHAO Yue, JIA Xuan, LIU Ya-ru, and LIU Dong-ming
In this work,biogas residues,the remnant of the anaerobic digestion,was used for composting with livestock manure as the co-substrate.It is important for improving the soil quality in China,because the negative influence of biogas residues being utilized directly as organic fertilizer (a mainstream way of disposing bioIn this work,biogas residues,the remnant of the anaerobic digestion,was used for composting with livestock manure as the co-substrate.It is important for improving the soil quality in China,because the negative influence of biogas residues being utilized directly as organic fertilizer (a mainstream way of disposing biogas residues in China) on the soil could be eliminated or mitigated via composting.The composition of composting substrate has a great influence on the composting process.To explore the influence of the composition of the initial mixtures on the physicochemical properties and spectroscopic characteristics of composts,fifteen co-composting of biogas residue,pig manure and chicken manure,with different material ratios,were carried out.Physicochemical and biological indicators were determined.Meanwhile,spectroscopic methods,such as UV-Vis,synchronous fluorescence and 3D-EEM spectra were used for identifyingcharacteristic spectral parameters companied with FRI and PARAFAC.Therefore,spectroscopic characteristics of composts were characterized.The relationship between physicochemical properties of composts and the composition of the initial mixtures was established using CCA.Similarly,that between spectroscopic characteristics of composts and the composition of the initial mixtures was also established.The results showed that:physicochemical properties of composts exhibits a significant correlation with the composition of the initial mixtures.A significant correlation between spectroscopic characteristics of composts and the composition of the initial mixtures was also observed.In the two CCA,the former four axes account for 83.9% and 97.5% of the total sample variation.The influence of enviro nmental factors on physicochemical properties of composts was in the order of pig manure amount>chicken manure amount>biogas residue amount and that on spectroscopic characteristics of composts was in the order of biogas residue amount>pig manure amount>chicken manure amount.Carbon-rich raw materials favor the maturation of compost.A high proportion of nitrogen-rich raw materials does not lead to the accumulation of ammonia in compost.A low proportion of biogas residue favors the formation of humic substances during the co-composting of biogas residue and livestock manure.In summary,the evaluation of compost fermentation effect should synthetically consider physic-chemical,biological indicators and spectral parameters instead of a single index..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2268 (2015)
Preliminary Research on Bubble Characteristics of Ancient Glaze Using OCT Technology
YAN Xin, DONG Jun-qing, LI Qing-hui, GUO Mu-sen, BU Gong, and HU Yong-qing
The bubble is one of the most common feature in ancient glaze.The size and distribution of bubbles are closely associated with recipes of the raw materials for the body and glaze and the making process.To characterize the bubbles is essential for the study of ceramic production process,production places,times characterThe bubble is one of the most common feature in ancient glaze.The size and distribution of bubbles are closely associated with recipes of the raw materials for the body and glaze and the making process.To characterize the bubbles is essential for the study of ceramic production process,production places,times characteristics and so on.In order to explore the possibility of using the optical coherence tomography (OCT) imaging technology to characterize the bubbles and the bubble distribution characteristic in glaze of ancient porcelain,sweep frequency OCT imaging system is used to detect five different types ancient porcelain chips.According to the two dimensional sectional images and three dimensional tomographic images of the transparent layer of glaze obtained by the OCT imaging system,the two dimensional sectional images characteristics and three dimensional slices characteristics of the bubbles in glaze are studied.The bubble characteristics in the glaze and its possible causes that gases in the body of the ceramic overflow to the glaze layer in the firing process are comprehensively analyzed.Meantime,the size of bubble is calculated according to the two dimensional sectional images based on pixel,and the result is compared with the traditional microscopic test result.The bubble size,two dimensional sectional characteristics and three dimensional tomographic image characteristics of opaque glaze are also studied.Experimental results show that the bubble characteristics in glaze of different ancient porcelain chips are obvious difference,the result of the bubble size calculated based on pixel coincides with the result of the bubble size observed by traditional microscope with ten times magnification,slices of the body near the body-glaze binding region based on OCT imaging technology three dimensional tomography can effectively reflect the bubble characteristics in glaze.The measurement of using OCT imaging technology to characterize bubble characteristics of the glaze is proposed,and the feasibility and the validity of the measurement are certified,and the nondestructive detection of bubble characteristics in ancient porcelain glaze is realized.Especially for the analysis of bubble characteristics of opaque glaze,the OCT imaging technology overcomes the limitations of using the traditional microscope technology to study the distribution of bubble in glaze in the past,and provides a novel,reliable analysis method for the analysis of ceramic glaze bubble characteristics..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2275 (2015)
Measurement of Mole Ratio for Alkali Metal Mixture by Using Spectral Absorption Method
ZOU Sheng, ZHANG Hong, CHEN Yao, and CHEN Xi-yuan
The ratio of alkali metal mixture is one of the most important parameters in gauge head belonging to the ultra-sensitivity inertial measurement equipment,which is required to detect precisely.According to the feature that ratio of alkali metal is related to alkali metal vapor density,the theory of optical depth is usedThe ratio of alkali metal mixture is one of the most important parameters in gauge head belonging to the ultra-sensitivity inertial measurement equipment,which is required to detect precisely.According to the feature that ratio of alkali metal is related to alkali metal vapor density,the theory of optical depth is used to detect the ratio of alkali metal in the present article.The result shows that the data got by the theory of optical depth compared with empirical formula differs at three orders of magnitude,which can’t ensure the accuracy.By changing the data processing method,model between spectral absorption rate and temperature in cell is established.The temperature in alkali metal cell is calibrated by spectral absorption rate.The ratio of alkali metal atoms in the cell is analyzed by calculating the alkali density with empirical formula.The computational error is less than 10%..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2281 (2015)
Effects of Temperature on the Preparation of Al/Zn3N2 Thin Films Using Magnetron Reactive Sputtering
FENG Jun-qin, and CHEN Jun-fang
The effects of substrate temperature on the plasma active species were investigated by plasma optical emission spectroscopy.With increasing substrate temperature,the characteristic spectroscopy intensity of the first positive series of N2 (B3Πg→A3Σ+u),the second positive N2 (C3Πu→B3Πg),the first negative series N+2 (B2The effects of substrate temperature on the plasma active species were investigated by plasma optical emission spectroscopy.With increasing substrate temperature,the characteristic spectroscopy intensity of the first positive series of N2 (B3Πg→A3Σ+u),the second positive N2 (C3Πu→B3Πg),the first negative series N+2 (B2Σ+u→X2Σ+g) and Zn are increased.Due to the substrate temperature,each ion kinetic energy is increased and the collision ionization intensified in the chamber.That leading to plasma ion density increase.These phenomenons’s show that the substrate temperature raises in a certain range was conducive to zinc nitride thin films growth.Zn3N2 thin films were prepared on Al films using ion sources-assisted magnetron sputtering deposition method.The degree of crystalline of the films was examined with X-ray diffraction (XRD).The results show that has a dominant peak located at 34.359°in room temperature,which was corresponding to the (321) plane of cubic anti-bixbyite zinc nitride structure (JCPDS Card No35-0762).When the substrate temperature was 100 ℃,in addition to the (321) reflection,more diffraction peaks appeared corresponding to the (222),(400) and (600) planes,which were located at 31.756°,36.620° and 56.612°respectively.When the substrate temperature was 200 ℃,in addition to the (321),(222),(400) and (600) reflection,more new diffraction peaks also appeared corresponding to the (411),(332),(431) and (622) planes,which were located at 39.070,43.179°,47.004° and 62.561°respectively.These results show the film crystalline increased gradually with raise the substrate temperature.XP-1 profilometer were used to analyze the thickness of the Zn3N2 films.The Zn3N2 films deposited on Al films in mixture gas plasma had a deposition rate of 2.0,2.2,and 2.7 nm·min-1.These results indicate that the deposition rate was gradually enhanced as substrate temperature increased.Field emission scanning electron microscope (SEM) images revealed that the particles of zinc nitride thin films became smaller but more uniform and density with increase the substrate temperature.The Zn3N2 thin films were strongly bound on the Al films.The experiments of films properties analysis results about the substrate temperature were consistent with the results of the plasma optical emission spectroscopy.The results would help improving the preparation of magnetron sputtering technique and getting better Zn3N2 thin films.On the other hand,the results were reflected that the plasma emission spectrum was fast and effective method to analyze the intrinsic characteristics of plasma..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2287 (2015)
Synthesis and Properties of 1,11,15,25-Tetrahydroxy-4,8,18,22-Di(Bridged Dipropionate Carboxyl) Phthalocyanine Copper
XIA Dao-cheng, LI Wan-cheng, LI Jie-jun, WANG Gai-ping, DUAN Hong-wei, REN Xu-wen, FENG Kai, LI Pei-tao, WANG Hui-fang, and PU Gai-qin
In this dissertation,we study the synthesis and character of new substituted Phthalocyanine.Due to the widely application of Pcs in the fields,such as the communication,medical treatment,chemical industry and so on,therefore,they have been a hot topic over several decades by scientists.Nowadays,scientists have preparedIn this dissertation,we study the synthesis and character of new substituted Phthalocyanine.Due to the widely application of Pcs in the fields,such as the communication,medical treatment,chemical industry and so on,therefore,they have been a hot topic over several decades by scientists.Nowadays,scientists have prepared thousands of Pcs and their derivatives.However,along with the human society development and the progress in science and technology,the new phthalocyanine with novle characteristics are still the goal of the scientists.In this dissertion,the synthetic methods of the phthlocyanine is improved.The synthesis and characterization of 1,11,15,25-tetrahydroxy-4,8,18,22-di(bridged dipropionate carboxyl) phthalocyanines are reported in this paper.The mixtures of malonic acid and 3,6-dihydroxy-phthalonitrile was added to water under stiriing.Then,a catalyst amount of sulfuric acid was added.The first synthetic precursor,i.e.,malonic acid 3,3′-bis(6-hydroxy phthalonitrile) butter,its molecular formula is C19H8N4O6.phthalocyanines was prepared by malonic acid 3,3′-bis(6-hydroxy phthalonitrile) butter and dihydrate zinc acetate,copper acetate monohydrate in n-amyl alcohol,using DBU as a catalyst under the 135 ℃,molecular formula of phthalocyanine complexes is C38H16N8O12M.The product was characterized by Ultraviolet-visible (UV/Vis) Spectrum absorption and fluorescence,The results are agreement with the proposed structures.And electrochemical properties were studied..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2292 (2015)
Simultaneous Detection of External and Internal Quality Parameters of Huping Jujube Fruits using Hyperspectral Imaging Technology
XUE Jian-xin, ZHANG Shu-juan, and ZHANG Jing-jing
Nondestructive detection of external and internal quality parameters of jujube is crucial for improving jujube’s shelf life and industry production.Hyperspectral imaging is an emerging technique that integrates conventional imaging and spectroscopy to acquire both spatial and spectral information from a sample.It takesNondestructive detection of external and internal quality parameters of jujube is crucial for improving jujube’s shelf life and industry production.Hyperspectral imaging is an emerging technique that integrates conventional imaging and spectroscopy to acquire both spatial and spectral information from a sample.It takes the advantages of the conventional RGB,near-infrared spectroscopy,and multi-spectral imaging.In this work,hyperspectral imaging technology covered the range of 450~1 000 nm has been evaluated for nondestructive determination of “natural defects” (shrink,crack,insect damage and peck injury) and soluble solids content(SSC) in Huping jujube fruit.400 RGB images were acquired through four different defect (50 for each stage) and normal(200) classes of the Huping jujube samples.After acquiring hyperspectral images of Huping jujube fruits,the spectral data were extracted from region of interests(ROIs).Using Kennard-Stone algorithm,all kinds of samples were randomly divided into training set (280) and test set (120) according to the proportion of 3∶1.Seven principal components (PCs) were selected based on principal component analysis (PCA),and seven textural feature variables (contrast,correlation,energy,homogeneity,variance,mean and entropy) were extracted by gray level co-occurrence matrix (GLCM).The least squares support vector machine (LS-SVM) models were built based on the PCs spectral,textural,combined PCs and textural features,respectively.The satisfactory results show the correct discrimination rate of 92.5% for the prediction samples,as well as correlation coefficient (Rp) of 0.944 for the prediction set to calculate SSC content based on PCs and textural features.The study demonstrated that hyperspectral image technique can be a reliable tool to simultaneous detection of external (“natural defects”) and internal (SSC) quality parameters of Huping jujube fruits,which provided a theoretical reference for nondestructive detection of jujube fruit..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2297 (2015)
Research and Application of the ICP-MS Detection Technology for the Content of Nb and Ta in Geochemical Sample
LI Zi-qiang, LI Xiao-ying, ZHU Kun, XU Xiao-xia, and YAN Zhi-yuan
In order to provide the test analysis technology to support the exploration and development of niobium and tantalum resource,based on the special chemical properties of Nb and Ta in geochemical sample,we studied the detection methods for the content of Nb and Ta in geochemical sample by using inductively coupled plasmaIn order to provide the test analysis technology to support the exploration and development of niobium and tantalum resource,based on the special chemical properties of Nb and Ta in geochemical sample,we studied the detection methods for the content of Nb and Ta in geochemical sample by using inductively coupled plasma mass spectrometry (ICP-MS).The results show that the sample dissolution and instrumental parameter of ICP-MS,especially the former have significant influence?on detection results.Therefore,optimizing important parameters of sample dissolution is the key of the detection technology.The optimal parameters are that:the weight of sample is 50 mg;the dosage of HF acid is 15 mL;the concentration of nitric acid and tartaric acid in the sample solution is 2% and 1.5%,respectively;the validity period of detection for sample solution ≤1 d.The detection method has been validated by the national geochemistry standard reference material.The precise and exaction of method meet the required of industry standards.The detection limits of method for Nb and Ta are 1.05 and 0.13 μg·g-1,respectively.The experiment proved that the ICP-MS detection methods,which using certain preparation process of sample solutions,is suitable for accurate and rapid determination of Nb and Ta in geochemical sample,especially geochemical survey samples which with a large amount and low content of Nb and Ta..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2303 (2015)
Investigation of Cu Concentration in the CuSO4 Solution by Laser Induced Breakdown Spectroscopy
ZHANG Ya-wei, GAO Xun, ZHANG Yuan, YUAN Tong, and LIN Jing-quan
In this paper,the concentration of copper element in the CuSO4 solution was measured by Laser Induced Breakdown Spectroscopy with aqueous jets.We used the CuSO4 solution with 7 kinds of concentration and adopted statistical exploratory data analysis method to get calibration curve of Cu,whose linear fitting coefficientIn this paper,the concentration of copper element in the CuSO4 solution was measured by Laser Induced Breakdown Spectroscopy with aqueous jets.We used the CuSO4 solution with 7 kinds of concentration and adopted statistical exploratory data analysis method to get calibration curve of Cu,whose linear fitting coefficient R2 was larger than 0.98.The average RSD of LIBS was 6.96%,and the average LOD of Cu was determined to be 12 ppm.The values of relative error by analyzing Cu Ⅰ 324.75 nm and Cu Ⅰ 327.40 nm spectral lines were respectively 6.52% and 5.86%,with the method called leave-one-out cross validation.The experimental relative error had a greater value,which was 10.3%,when the concentration of Cu was 10 ppm.However,the relative error decreased to 1.1% for the concentration of 2 000 ppm,which indicated that LIBS need to be studied on its accuracy further in detecting lower analytical concentrations.LIBS has the promising application in detecting heavy metal elements in the environmental wastewater pollution..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2308 (2015)
Determination of Total Iron and Fe2+ in Basalt
LIU Jian-xun, CHEN Mei-rong, JIAN Zheng-guo, WU Gang, and WU Zhi-shen
Basalt is the raw material of basalt fiber.The content of FeO and Fe2O3 has a great impact on the properties of basalt fibers.ICP-OES and dichromate method were used to test total Fe and Fe2+ in basalt.Suitable instrument parameters and analysis lines of Fe were chosen for ICP-OES.The relative standard deviation (RSD) Basalt is the raw material of basalt fiber.The content of FeO and Fe2O3 has a great impact on the properties of basalt fibers.ICP-OES and dichromate method were used to test total Fe and Fe2+ in basalt.Suitable instrument parameters and analysis lines of Fe were chosen for ICP-OES.The relative standard deviation (RSD) of ICP-OES is 2.2%,and the recovery is in the range of 98%~101%.The method shows simple,rapid and highly accurate for determination of total Fe and Fe2+ in basalt.The RSD of ICP-OES and dichromate method is 0.42% and 1.4%,respectively..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2312 (2015)
Spectroscopic Research on Slag Nanocrystal Glass Ceramics Containing Rare Earth Elements
OUYANG Shun-li, LI Bao-wei, ZHANG Xue-feng, JIA Xiao-lin, ZHAO Ming, and DENG Lei-bo
The research group prepared the high-performance slag nanocrystal glass ceramics by utilizing the valuable elements of the wastes in the Chinese Bayan Obo which are characterized by their symbiotic or associated existence.In this paper,inductively coupled plasma emission spectroscopy (ICP),X-ray diffraction (XRD),RamanThe research group prepared the high-performance slag nanocrystal glass ceramics by utilizing the valuable elements of the wastes in the Chinese Bayan Obo which are characterized by their symbiotic or associated existence.In this paper,inductively coupled plasma emission spectroscopy (ICP),X-ray diffraction (XRD),Raman spectroscopy (Raman) and scanning electron microscopy (SEM) are all used in the depth analysis for the composition and structure of the samples.The experiment results of ICP,XRD and SEM showed that the principal crystalline phase of the slag nanocrystal glass ceramics containing rare earth elements is diopside,its grain size ranges from 45 to 100 nm,the elements showed in the SEM scan are basically in consistent with the component analysis of ICP.Raman analysis indicated that its amorphous phase is a three-dimensional network structure composed by the structural unit of silicon-oxy tetrahedron with different non-bridging oxygen bonds.According to the further analysis,we found that the rare earth microelement has significant effect on the network structure.Compared the nanocrystal slag glass ceramic with the glass ceramics of similar ingredients,we found that generally,the Raman band wavenumber for the former is lower than the later.The composition difference between the glass ceramics and the slag nanocrystal with the similar ingredients mainly lies on the rare earth elements and other trace elements.Therefore,we think that the rare earth elements and other trace elements remains in the slag nanocrystal glass ceramics have a significant effect on the network structure of amorphous phase.The research method of this study provides an approach for the relationship among the composition,structure and performance of the glass ceramics..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2316 (2015)
Decomposition of X-Ray Fluorescence Overlapping Peaks Based on Statistical and Genetic Algorithms
HUANG Hong-quan, DING Wei-cheng, GONG Di-chen, and FANG Fang
In fluorescence analysis,the phenomenon of overlapping often occurs among adjacent peaks.In the view of the random physical properties of formation process of X fluorescence spectra,Gaussian Mixture Statistics Model (GMSM) and Genetic Algorithms were used for the decomposition of overlapping peaks.First,the GMSM was prIn fluorescence analysis,the phenomenon of overlapping often occurs among adjacent peaks.In the view of the random physical properties of formation process of X fluorescence spectra,Gaussian Mixture Statistics Model (GMSM) and Genetic Algorithms were used for the decomposition of overlapping peaks.First,the GMSM was proposed to describe the overlapping peaks,and the local convergence problem of expectation maximization (EM) was analyzed.Secondly,the GMSM parameters were regarded as individual genes,and the log-likelihood function of overlapping peaks random data was set as fitness function.A fast algorithm for the objective function value was proposed.Finally,the population search technology of Genetic Algorithm was used to find the global optimal solution,and to realize the decomposition of overlapping peaks.All measured data were regarded as “useful” data.The “useful” degree was reflected by their probability.The GMSM method can achieve the “best match” effect in the maximum global probability with zero loss of original data,which can fit the random of radiation measurement process.The decomposition experiments of four serious overlapping peaks show high precision of the peak position,peak area and standard deviation.The maximum error was 0.7 channel,2.3% and 2.17%,respectively,which is especially suitable for the condition of serious overlap and can be widely used for the decomposition of other energy spectrum..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2320 (2015)
Time-Resolved XEOL Experiment System on BL14W1 at SSRF
ZHANG Zhao-hong, JIANG Zheng, XUE Song, and ZHENG Li-fang
A novel time-resolved X-ray excited optical luminescence(TRXEOL) experiment system was developed for X ray absorption fine structure spectroscopy(XAFS) beamline at Shanghai Synchrotron Radiation Facility(SSRF).The TRXEOL system is composed of three parts:timing system,spectrometer system and nuclear instrument module(NA novel time-resolved X-ray excited optical luminescence(TRXEOL) experiment system was developed for X ray absorption fine structure spectroscopy(XAFS) beamline at Shanghai Synchrotron Radiation Facility(SSRF).The TRXEOL system is composed of three parts:timing system,spectrometer system and nuclear instrument module(NIM) system.These three systems were integrated to measure and record the optical luminescence from the sample excited by the synchrotron X-ray pulses,according to the time-correlated single photon counting methodology.It’s the first time in the domestic synchrotron radiation facilities to achieve TRXEOL experiment using the synchrotron X-ray pulses and the time structure of the storage ring.In this work,a SSRF-self-developed timing system was used,which is based on the Field programmable Gate Array and the high-speed serial communication technology.The timing system can provide trigger pulse synchronized with the X-ray pulse.The timing jitter is about 6 ps,and the timing delay resolution is 5 ps.The NIM system is the core of the TRXEOL experiment system,it has three main modules:the Co nstant Fraction Discriminator(CFD),the Time to Amplitude Converter(TAC) and the Multi-Channel Analyzer(MCA).During one excitation circle,the spectrometer and the Photomultiplier Tube detector tra nslate the induced luminescence of the sample excited by a single X-ray pulse into electrical pulse.The CFD module eliminates the timing walk larger than 50 ps induced by the amplitude of the electrical pulse.The TAC module calculates the time interval between the timing trigger pulse and the luminescence electrical pulse,and converts the interval into proportional amplitude of voltage.After plenty of circles,the MCA module gets the luminescence decay curve by recording and analyzing the voltage signals.And the data acquisition system gets the TRXEOL spectra by scanning the spectrometer and acquiring the frequency of the voltage pulses from the TAC module.The TRXEOL experiment system hel ps researchers measure optical decay curves and spectra of the sample in different time windows.Many luminescence behaviors would be explained more deeply,together with the aid of the optical XAFS to get the electron structure of the sample.A sample of ZnO nanowire was studied using the TRXEOL system.The ordinary XEOL spectrum obtained could distinguish the 390 nm wavelength and the 500 nm wavelength luminescence center.The decay curve at 0 nm wavelength could clearly show the fast luminescence process and the slow luminescence process.The full width at half maximum of the fast luminescence decay curve was about 0.5 ns,showing that the minimum time resolution of the TRXEOL system is less than 1 ns.The TRXEOL spectra obtained could respectively get the luminescence information within different time windows.It was demo nstrated that the TRXEOL system is not only feasible and reliable,but also supply XAFS beamline with the technical preparatio ns of time resolved techniques..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2324 (2015)
A Comparison of Arsenic Speciation in 13 Pteris Vittata L.Populations
WAN Xiao-ming, LIU Ying-ru, LEI Mei, HUANG Ze-chun, and CHEN Tong-bin
Synchrotron radiation X-ray absorption near edge structure was employed to study the arsenic (As) speciation in 13 Pteris vittata L.populations collected from 7 provinces,cities,and autonomous regions in China.As in roots of P.vittata was mainly combined with oxygen (O),with a small amount of As combined with glutathioSynchrotron radiation X-ray absorption near edge structure was employed to study the arsenic (As) speciation in 13 Pteris vittata L.populations collected from 7 provinces,cities,and autonomous regions in China.As in roots of P.vittata was mainly combined with oxygen (O),with a small amount of As combined with glutathione (GSH).Populations from Hunan and Guangxi provinces showed higher percentages of As-GSH in soots.As in roots of P.vittata was predominated with As(Ⅴ),with the percentage of As(Ⅴ) to the total As being 59.6±0.6%~83.8±3.8%.The As(Ⅴ) percentage was in the order of HN5HN3>HN1>TW>CQ>AH>FJ>HN5>HN2>GX2>GX3>HN4>GX1,within the range of 2.4%~12.9%.Different from that in roots,As in shoots was predominated with As(Ⅲ),with no As(Ⅴ) detected.The disclosure of As speciation in the roots and shoots of P.vittata contributes to the future research on As accumulation mechanism..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2329 (2015)
Spectral Analysis of Trace Fluorine Phase in Phosphogypsum
ZHAO Hong-tao, LI Hui-quan, BAO Wei-jun, WANG Chen-ye, LI Song-geng, and LIN Wei-gang
Phosphogypsum,which contains more than 90% of the calcium sulfate dihydrate(CaSO4·2H2O),is a kind of important renewable gypsum resources.Unlike the natural gypsum,however,phosphorus,fluorine,organic matter and other harmful impurities in phosphogypsum limit its practical use.To ascertain the existence form,contenPhosphogypsum,which contains more than 90% of the calcium sulfate dihydrate(CaSO4·2H2O),is a kind of important renewable gypsum resources.Unlike the natural gypsum,however,phosphorus,fluorine,organic matter and other harmful impurities in phosphogypsum limit its practical use.To ascertain the existence form,content and phase distribution of trace fluoride in phosphogypsum has important theoretical values in removing trace fluoride effectively.In this present paper,the main existence form and phase distribution of trace fluoride in phosphogypsum was investigated by the combination of X-ray photoelectron spectroscopy (XPS) and Electron microprobe analysis (EMPA).The results show that trace fluoride phase mainly includes NaF,KF,CaF2,K2SiF6,Na2SiF6,Na3AlF6,K3AlF6,AlF3·3H2O,AlF2.3(OH)0.7·H2O,Ca5(PO4)3F,Ca10(PO4)6F2.Among them,4.83% of fluorine exists in the form of fluoride (NaF,KF,CaF2);Accordingly,8.43% in the form of fluoride phosphate(Ca5(PO4)3F,Ca10(PO4)6F2);12.21% in the form of fluorine aluminate(Na3AlF6,K3AlF6);41.52% in the form of fluorosilicate(K2SiF6,Na2SiF6);33.02% in the form of aluminum fluoride with crystal water(AlF3·3H2O,AlF2.3(OH)0.7·H2O).In the analysis of phase constitution for trace elements in solid samples,the method of combining XPS and EMPA has more advantages.This study also provides theoretical basis for the removal of trace fluorine impurity and the effective recovery of fluorine resources..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2333 (2015)
Automatic Recognition of Overlapped Spectral Peaks by Combined Symmetric Zero-Area Conversion and L-M Fitting
BI Yun-feng, LI Ying, DU Zeng-feng, CHEN Liang, and ZHENG Rong-er
The peaks’ overlapping often exists in Raman spectroscopy analysis,because of the low spectral resolution of the spectrograph and the complex sample components.The overlapped peaks lead to the errors in peak parameters extraction easily,and at last lead to the analysis error of sample components,which increases the difThe peaks’ overlapping often exists in Raman spectroscopy analysis,because of the low spectral resolution of the spectrograph and the complex sample components.The overlapped peaks lead to the errors in peak parameters extraction easily,and at last lead to the analysis error of sample components,which increases the difficulty in automatic analysis of field spectra.The identification of overlapped peaks is the key difficulty of in-situ spectra analysis.To solve this problem,an automatic method of identifying the overlapped peaks was established basing on an analysis model with multiple Gaussian shape peaks.The peak number and the initial parameters(the peak position,peak height,and width) were obtained by symmetric zero-area transformation firstly,and then the parameters were optimized by Levenberg-Marquardt fitting method eventually.Some algorithm experiments were executed to test the method respectively by simulated data and Raman spectra data,and the former showed that the symmetric zero-area transformation method can extract the initial peak parameters with high accuracy,and then converges fast,and is adaptive to signal with wide dynamic range of SNR ,but has false and omissive peaks to low SNR signal.The research results show that the automatic method of identifying the overlapped peaks with symmetric zero-area transformation combined with L-M fitting has a certain practical value..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2339 (2015)
Moving Mirror Scanning System Based on the Flexible Hinge Support
XIE Fei, FENG Fei, WANG Fu-bei, WU Qiong-shui, and ZENG Li-bo
In order to improve moving mirror drive of Fourier transform infrared spectrometer,we design a dynamic scanning system based on flexible hinge support.Using the flexible hinge support way and the voice coil motor drive mode.Specifically,Using right Angle with high accuracy high stability type flexible hinge support mecIn order to improve moving mirror drive of Fourier transform infrared spectrometer,we design a dynamic scanning system based on flexible hinge support.Using the flexible hinge support way and the voice coil motor drive mode.Specifically,Using right Angle with high accuracy high stability type flexible hinge support mechanism support moving mirror,dynamic mirror can be moved forward and backward driven by voice coil motor reciprocating motion,DSP control system to control the moving mirror at a constant speed.The experimental results show that the designed of moving mirror scanning system has advantages of stability direction,speed stability,superior seismic performance..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2343 (2015)
Calibration Method for the Monochromator Based on Continuous Spectrum Light Source
ZHANG Lei, and DAI Jing-min
For the inevitable errors of the monochromator in the process of producing and installing,it must be calibrated before being used.For the traditional calibration method using mercury lamp,the number of wavelengths limits the calibration precision of the monochromator.Based on the principle of grating monochromator,caliFor the inevitable errors of the monochromator in the process of producing and installing,it must be calibrated before being used.For the traditional calibration method using mercury lamp,the number of wavelengths limits the calibration precision of the monochromator.Based on the principle of grating monochromator,calibration method for the monochromator based on continuous spectrum light source is proposed.Calibration system is designed and built,which is composed of broadband light source using tungsten halogen lamp,power source,light filter,the monochromator,spectroscopy to detect the intensity of the monochromator output,and computer.Divide the intensity detected on the output of monochromator by the intensity detected directly the tungsten halogen lamp.The result is the transmissivity function of the monochromator eliminating the influence of the halogen tungsten lamp radiation and the spectrometer response function.On a certain dial number,the transmissivity function is measured,normalized and the peak wavelength is calculated.22 groups of wavelength data and dial number are acquired.8,14,18,22 points are chosen separately to calibrate the relationship between the wavelength and the dial number of monochromator by linear fitting and quadratic fitting.Experimental results show the calibration result in 22 points is better than others,(8 points similar to the calibration method using mercury lamp).The result of quadratic fitting with 22 points as the finalresult is better than linear fitting.So the calibration method for monochromator using the continuous spectrum light source with more calibration points is superior to the traditional calibration method using mercury lamp..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2348 (2015)
Research on Assessment Methods of Spectrum Data Quality of Core Scan
XIU Lian-cun, ZHENG Zhi-zhong, YIN Liang, CHEN Chun-xia, YU Zheng-kui, HUANG Bin, ZHANG Qiu-ning, XIU Xiao-xu, and GAO Yang
Core scan is the instrument used for core spectrum and pictures detection that has been developed in recent years.Cores’ data can be digitized with this equipment,then automatic core catalog can be achieved,which provides basis for geological research,mineral deposit study and peripheral deposit prospecting.Meanwhile,aCore scan is the instrument used for core spectrum and pictures detection that has been developed in recent years.Cores’ data can be digitized with this equipment,then automatic core catalog can be achieved,which provides basis for geological research,mineral deposit study and peripheral deposit prospecting.Meanwhile,an online database of cores can be established by the means of core digitalization to solve the cost problem caused by core preservation and share resources.Quality of core data measurement directly affects the mineral identification,reliability of parameter inversion results.Therefore it’s very important to quasi-manage the assessment of data quality with the instrument before cores’ spectrum testing services.Combined with the independent R&D of CSD350A type core scan,and on the basis of spectroscopy basic theory,spectrum analysis methods,core spectrum analysis requirements,key issues such as data quality assessment methods,evaluation criteria and target parameters has been discussed in depth,and comprehensive assessment of independent R&D of core scan has been conducted,which indicates the reliability and validity of spectrum measurements of the instrument.Experimental tests show that the methods including test parameters and items can perfectly response the measurements of reflectance spectrum,wavelength accuracy,repeatability and signal to noise ratio with the instrument.Thus the quality of core scan data can be evaluated correctly,and the foundation of data quality for commercial services can be provided.In the case of the current lack of relevant assessment criteria,the method this study proposes for the assessment has great value in the work of core spectrum measurements..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2352 (2015)
Biological Process Oriented Online Fourier Transform Infrared Spectrometer
XIE Fei, WU Qiong-shui, and ZENG Li-bo
An online Fourier Transform Infrared Spectrometer and an ATR (Attenuated Total Reflection) probe,specifically at the application of real time measurement of the reaction substrate concentration in biological processes,were designed.(1) The spectrometer combined the theories of double cube-corner reflectors and flat mirAn online Fourier Transform Infrared Spectrometer and an ATR (Attenuated Total Reflection) probe,specifically at the application of real time measurement of the reaction substrate concentration in biological processes,were designed.(1) The spectrometer combined the theories of double cube-corner reflectors and flat mirror,which created a kind of high performance interferometer system.The light path folding way was utilized to makes the interferometer compact structure.Adopting double cube-corner reflectors,greatly reduces the influence of factors in the process of moving mirror movement such as rotation,tilt,etc.The parallelogram oscillation flexible support device was utilized to support the moving mirror moves.It cancelled the friction and vibration during mirror moving,and ensures the smooth operation.The ZnSe splitter significantly improved the hardware reliability in high moisture environment.The method of 60° entrance to light splitter improves the luminous flux.(2)An ATR in situ measuring probe with simple structure,large-flux,economical and practical character was designed in this article.The transmission of incident light and the light output utilized the infrared pipe with large diameter and innerplanted-high plating membrane,which conducted for the infrared transmission media of ATR probe.It greatly reduced the energy loss of infrared light after multiple reflection on the inner wall of the light pipe.Therefore,the ATR probe obtained high flux,improved the signal strength,which make the signal detected easily.Finally,the high sensitivity of MCT (Mercury Cadmium Telluride) detector was utilized to realize infrared interference signal collection,and improved the data quality of detection.The test results showed that the system yields the advantages of perfect moisture-proof performance,luminous flux,online measurement,etc.The designed online Fourier infrared spectrometer can real-time measured common reactant substrates such as glycerin in the bioreactor under high quality.There is a large potential market,such as online analysis in biological,chemical testing and material analysis..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2357 (2015)
A New Strategy of Spectrum and Polarization Measuring based on LCVR and AOTF
WANG Yao-li, ZHANG Rui, WANG Zhi-bin, WEN Ting-dun, and LI Ke-wu
In view of the existing relatively cumbersome polarization measurement method of using liquid crystal phase variable retarder (LCVR) and acousto-optic tunable filter (AOTF),a new strategy of spectrum and polarization measurement is put forward.This method removed mechanical movement and reduced the amount of phase delaIn view of the existing relatively cumbersome polarization measurement method of using liquid crystal phase variable retarder (LCVR) and acousto-optic tunable filter (AOTF),a new strategy of spectrum and polarization measurement is put forward.This method removed mechanical movement and reduced the amount of phase delay from four groups to two groups.This method realizes the spectrum and polarization measurements by measuring the plus and minus 1 level diffraction light of the system with two LCVR,one AOTF and two same version detectors.For the polarization measurement of a particular wavelength,the computer controlled LCVR driving voltage to achieve the required phase delay in accordance with the requirements of the wavelength,it also controlled the driving frequency to implement the required wavelength selection of AOTF.Because of the different driving frequencies of AOTF corresponding to the different wavelengths,so it can get the spectral information by scanning the whole frequency bands,In this paper detailed principles are deduced and the polarization model of AOTF is analyzed,it also deduced the measurement formula of I,Q,U in the corresponding Stokes parameter through the theoretical calculation Muller matrix of the LCVR and AOTF.Finally it analyzed and simulated the measurement error of the whole system which was caused by the tiny deviation of phase delay,the simulation results show that relative error <3% when the phase delay amount within the range of ±π/100.This experiment proved the feasibility and accuracy of the measurement system,the results show that the error of the measuring system overall <6%.This study provides a new method of polarization measurement which is simple,feasible and precise,it has important application value..
Spectroscopy and Spectral Analysis
- Publication Date: Jan. 01, 1900
- Vol. 35, Issue 8, 2362 (2015)
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