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2018 Vol. 38, No. 02 Published: 2018-02-01

	333	Transient Measure Technique for Excitation Temperature and Radiation Temperature Based on Multi-Spectral Method
		ZHU Ze-zhong^1，2, SHEN Hua^1，2*, WANG Nian^1，2, ZHU Ri-hong^1，2
		DOI: 10.3964/j.issn.1000-0593(2018)02-0333-07
		In recent years, with the rapid development of cutting-edge technology at domestic and foreign, temperature measurement has a very important guiding significance and research value in the field of national defense construction and industrial manufacturing. Especially in the transient ultrahigh temperature measurement, temperature measurement accuracy requirements are more stringent. Because of its high precision and applicability, multi spectral method is widely used by experts at domestic and foreign. In this paper, a new method is proposed to solve the transient excitation temperature and radiation temperature of the target with high accuracy at the same time. This method can obtain the target excitation temperature by finding the higher reliability of the target physical characteristic data and the more accurate multi spectral line fitting method. By establishing a more accurate mathematical model and algorithm, the effect of spectral emissivity on the whole process of temperature measurement is reduced. The relevant temperature measurement experiments show that the system temperature measurement accuracy of this method reached 3%.
		2018 Vol. 38 (02): 333-339 [Abstract] ( 354 ) RICH HTML PDF (4235 KB) ( 529 )

	340	Study on the Analytical Method of Thermally Stimulated Current Spectroscopy of CdZnTe Crystal
		FU Xu^1,2, WANG Fang-bao^1,2, XU Ling-yan^1,2, XU Ya-dong^1,2, JIE Wan-qi^1,2*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0340-06
		Thermally stimulated current (TSC) spectroscopy is a quite effective method for the defects studies in wide bandgap semiconductors, from which the physical information, i. e. defect types, activation energy (E_a，i), concentration (N_i) and capture cross-section (σ_i), can be given. The discrepancy and effects of heating-rate-dependent Arrhenius method and simultaneous multiple peak analysis (SIMPA) on the data processing results of TSC were studied in this work. The results indicated that Arrhenius method were more accurate in terms of the thermal activation energy of different traps. However, more heating rate, which meaned longer test cycles, were needed to maintain the accuracy. And also, this method could not deal with conditions of traps over-lap. In contrast, the SIMPA method could obtain the trap signatures (E_a，i, N_i, σ_i) with only one heating rate. However, parameters, i. e. β, E_a，i, σ_i and carrier mobility and lifetime product (μt), had significant effects on the peak position, height and width, which directly influenced the results of the fitting curve. Furthermore, the IRTM images of sample from the head of the ingots showed lower concentration of Te inclusions with belt-like distribution compared to that from the tail. Through the investigation of TSC spectroscopy, the concentration of shallow levels were much higher in the sample from the tail of the ingots than that from the head. The low temperature persistent photoconductivity (PPC) experiments showed a curvilineal variation for the tail sample. The results showed that the concentration and distribution of Te inclusions could probably result in the concentration variation of shallow trap centers, which present longer trapping time and shorter de-trapping time of optical excited carriers in crystal.
		2018 Vol. 38 (02): 340-345 [Abstract] ( 315 ) RICH HTML PDF (3474 KB) ( 165 )

	346	Study on Cavity Ring-Down Spectroscopy in High Power Ion Source
		HU Chun-dong^1，2, YAN Jing-yang^1，2, WANG Yan^1，2, LIANG Li-zhen^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0346-06
		High power ion source is a core component of neutral beam injector for tokamak. Negative ion source is the reference source for ITER neutral beam injection system as negative ion beam has a high neutralization efficiency in high energy. Cavity ring-down spectroscopy (CRDS) is a highly sensitive optical absorption spectroscopic technique. CRDS is able to measure the absolute line-of-sight integrated density of negative hydrogen ions based on photodetachment process. Compared with laser photodetachment method and optical emission spectroscopy, CRDS is insensitive to electromagnetic interference and doesn’t need plasma parameters for calculating, thus yielding reliable results. CRDS system is composed of laser, optical cavity, detector and data acquisition system. Equipment selection principle was analyzed. The basic principle of CRDS was presented, and then the analytical form of using CRDS to measure H^- density was derived in detail. CRDS has already been applied to high power ion source in laboratories of Germany, Japan and Italy. Results displayed that source parameters, including pressure and power, affected H^- density. H^- density increased from 10¹⁶ m^-3 magnitude to 10¹⁷ m^-3 magnitude in Cs seeded operation. The linearity between H^- density and extracted current was proved by NIFS.
		2018 Vol. 38 (02): 346-351 [Abstract] ( 207 ) RICH HTML PDF (3038 KB) ( 163 )

	352	Variety Identification of Bulk Commercial Coal Based on Full-Spectrum Spectroscopy Analytical Technique
		REN Yu^1,2, SUN Xue-jian^2*, DAI Xiao-ai¹, CEN Yi², TIAN Ya-ming¹, WANG Nan², ZHANG Li-fu²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0352-06
		To obtain the precise result, complex chemical analysis or complicated sample preparation is needed in universal coal analysis methods. In the paper, a new method to distinguish the type of bulk commercial coal using full spectroscopy which combined visible and near-infrared reflectance spectroscopy (Vis-NIRS) and short-wave infrared reflectance spectroscopy (SWIR) analytical technique and Multilayer Perceptron (MLP) classification method was advanced. The method was non-contact with no sample preparation and no chemical analysis. Besides, the classification information of coal can be quickly and efficiently obtained by this method. In the paper, the band range of original spectral data whose noise was excessive was deleted. The noise of remaining part was denoised by wavelet threshold denoising method. The spectral data pretreated was divided into three data sets: Vis-NIRS data set (500~900 nm), SWIR data set (1 000~2 350 nm) and full-spectrum data set (500~2 350 nm). Principal component analysis (PCA) was adopted in three datasets. The extracted principal components were entered in the MLP classification model. Multilayer perceptron was consist of input layer, hidden layers (two layers), softmax classifier. The contrastive study of classification accuracywas made among the three datasets. Random forest and Support Vector Machine (SVM) was used to verification analysis. The research showed: in the classification research of bulk commercial coal, because of the abundant data information of full-spectrum data, a better classification result can be obtained. When the number of training sample was 132, using the MLP classifier can achieve the highest classification accuracy which was 98.03%. The classification results of random forest and SVM verified the superiority and universality of the full spectrum dataset. The method provides reliable technical support for on-line analysis of coal and development of portable coal detecting instrument.
		2018 Vol. 38 (02): 352-357 [Abstract] ( 279 ) RICH HTML PDF (2335 KB) ( 388 )

	358	Laser Particle Size Analysis and Genesis of the Yellow Silt in the Coastal Area of South China
		WANG Jing¹, GAO Quan-zhou^1*, CHEN Guo-neng²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0358-09
		A layer of yellow silt is widely distributed on the low hills and platforms in the coastal area of south China. Seven typical sections in the study area were analyzed using laser grain size analysis to determine the sedimentary characteristics and genesis of the yellow slit. The typical loess, marine and fluvial deposits were also adopted for contrastive study. The results showed that the yellow silt sections were all featured by the modal size group of coarse silt (10~50 μm) and the secondary grain size of clay (<5 μm), which were corresponding to the “basic grain size group” and “second grain size group” of the typical loess, and the lithology were clayed silt. Aeolian characteristics of the yellow silt were further indicated by grain size parameters, scatter diagrams, frequency distributional curves and grain size index. The result of grain size discriminant analysis was negative, also supporting an aeolian origin of the yellow silt. All of the grain size characteristics of the yellow silt and the sedimentary type and environment they reflected were comparable to that of the typical loess, but quite different from associated fluvial and marine deposits.
		2018 Vol. 38 (02): 358-366 [Abstract] ( 180 ) RICH HTML PDF (6562 KB) ( 216 )

	367	Study on the Mechanism of Laser Paint Removal Based on LIBS and Time Resolved Characteristic Signal
		CHEN Lin, DENG Guo-liang, FENG Guo-ying^*, XUE Hong-yan, LI Jia-qi
		DOI: 10.3964/j.issn.1000-0593(2018)02-0367-05
		Laser paint stripping is an effective, clean and novel technology. The key for promoting the applications of this technology is to study the mechanisms involved in the process of laser paint removal. Based on the laser-induced breakdown spectroscopy (LIBS), we measured the plasma spectrum versus the irradiated pulse numbers. The electron density and temperature were calculated. Time resolved intensity of the spectrum peak, which corresponded to the characteristic element in the paint, was carried out. The results showed that the paint were stripped progressively as the number of the pulse increasing. The electron density and temperature decreased when the paint was removed. The signal corresponded to Ti lasts for several μs. It changed dramatically before and after the paint removal, which can be used to as a fast, accurate and online way to determine whether the paint has been clean out.
		2018 Vol. 38 (02): 367-371 [Abstract] ( 312 ) RICH HTML PDF (2740 KB) ( 153 )

	372	The Multi-Beam Interference Suppression for Measuring Penicillin Vial’s Oxygen Concentration Based on Tunable Diode Laser Absorption Spectroscopy
		ZHU Gao-feng^{1, 2}, HU Xin¹, ZHU Hong-qiu^1*, HU En-ze¹, ZHU Jian-ping³
		DOI: 10.3964/j.issn.1000-0593(2018)02-0372-05
		Penicillin vial’s oxygen concentration detection based on tunable diode laser absorption spectroscopy (TDLAS) was conducted in the open, on a single and short optical path. In this system, the multiple reflections and transmissions were caused by parallel glass walls, and the multi-beam interference impacted the signal wave form and the accuracy of the detection. A method was created tochange the incident angle of laser, and the influence of incident angle was the oretically analyzed to the distribution of transmission intensity. The calculation formula of incident angle was deductedin order that the superposition part of two coherent beamslocated in the outside of the detection range, and then the theoretical optimal incident angle was determined according to the field parameters. The 2f signal of sample(concentration 1%) was severally measured for many times in different time, and the signal to noise ratio (SNR) could be use as the optimization index of optimal angle. Finally, the actual optimal incident angle acquired in this system was determined. To compare with the optimal incident angle and the incident angle of high coefficient of determination, the concentration prediction result of cross validation showed that the correlation coefficients were 0.995 9 and 0.988 9 respectively. The former was 0.7% larger than the latter, and the root mean square errors of prediction (RMSEP) were 0.003 1 and 0.005 3 respectively. In addition, the former was reduced by 41.5% than the latter. This validates the effectiveness of the proposed method which can suppress the Multi-beam Interference and further improve the accuracy.
		2018 Vol. 38 (02): 372-376 [Abstract] ( 312 ) RICH HTML PDF (2131 KB) ( 367 )

	377	A Nearest Neighbor Search Algorithm for Color Based on Sequential NPsim Matrix
		ZHANG Ting^1,2, WANG Gong-ming^3*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0377-09
		The core of color nearest neighbor search based on spectral representation is high dimensional nearest neighbor searching, which is affected by equidistance of similarity measurement and low query efficiency of indexed tree seriously. To solve this problem, a color nearest neighbor search algorithm based on sequential NPsim matrix was proposed. First of all, the NPsim values between every two colors in color space were calculated and stored into the corresponding position of the NPsim matrix. After that, the elements in each raw of NPsim matrix were sorted in descending order to represent the similarity degree from strong to weak. Finally, the Top-K neighbors of given color can be found directly according to its raw number in the sequential NPsim matrix. To validate this algorithm, the nearest neighbor search algorithms based on KD-tree or SR-tree were compared on Munsell spectral data set. Experimental results indicated that the precise was better than that of other algorithms, the construction time of sequential NPsim matrix was longer than that of them, but the searching speed was more than thousands times of others and independent of K value. In addition, the construction of sequential NPsim matrix was easy to be paralleled to speed up, but the parallelization of construction of KD-tree or SR-tree was difficult.
		2018 Vol. 38 (02): 377-385 [Abstract] ( 211 ) RICH HTML PDF (2633 KB) ( 94 )

	386	Temperature Dependence of Terahertz Spectra of Amino Acid
		YU Jiang-ping¹, LI Chun², YI Wen-ting¹, JIN Biao-bing², LIU Yun-fei¹, JIANG Ling^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0386-08
		We employed terahertz time domain spectra (THz-TDS) to measure the spectra of L-Asparagine，L-Cysteine，L-Alanine and L-Tyrosine in the frequency range of 0.5～2 THz at different temperatures. We measured the terahertz absorption spectra of amino acids at room temperature, 250, 200, 150, 100, 70, 40, 10 and 4.5 K by cooling the samples. The absorption peaks of the four amino acids in the low frequency range (0.5～2 THz) were demonstrated by Fourier transform infrared spectroscopy (FTIR) at room temperature, and the range of high frequency band (3～6 THz) was measured by Raman strength of these four amino acids at room temperature using Raman spectroscopy. Measurement results indicated that the temperature variation had an important effect on the absorption spectra. When the temperature falled, the absorption peak shifted to higher frequencies, and several new absorption peaks appeared. Aliphatic and aromatic amino acid displayed different responses in the line width and the absorption strength. Furthermore, we used the quantum chemistry Gaussian 09 software package to calculate the THz spectra of one molecule and unit cell of L-Asparagine and L-Tyrosine at room temperature by density functional theory. The calculation results indicate that intermolecular vibration and rotation strongly influence the absorption in THz frequencies for L-Asparagine and L-Tyrosine.
		2018 Vol. 38 (02): 386-393 [Abstract] ( 280 ) RICH HTML PDF (4929 KB) ( 237 )

	394	Background Subtraction Method of TERS Topography Imaging Based on B-Spline
		FAN Xian-guang¹, WANG Xiao-dong¹, WANG Xin^1*, XU Ying-jie¹, QUE Jing¹, TANG Ming¹, HE Hao¹, ZUO Yong²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0394-07
		In the topography imaging of Tip-Enhanced Raman Spectroscopy, the difficulty of keeping the tip and the scan stage absolutely parallel, the fast change of the height of the tip due to the quick variety of the electron density, and the long response time of the scanning control system result in imaging background with inclined or boundary curly. Imaging background would bring a negative impact to the identification and analysis of the sample’s topographic image，while background subtraction is an important means to solve this problem, which is also an important part of topographic image’s preprocessing. The general principle of background subtraction is to fit the topographic image’s background firstly and then subtract it from the image. The traditional fitting method is polynomial fitting line by line, but this method will always destroy the sample’s actual spatial topography by over-fitting, and it is prone to leave clear line texture on the image. In this paper, the traditional method was improved, and the B-spline surface fitting method was used to approach the background of topographic image through constant iteration. The advantage of B-spline surface, namely low-order and smoothness, can help the method overcome the disadvantages of traditional polynomial method. In the experiments, the topographic image of Au (111) single-crystal and synthetic golden slice were detected, and then the proposed method and the traditional method were applied to perform background subtraction. Experimental results showed that the proposed method can eliminate the topographic image’s background effectively without destroying the sample’s actual spatial topography by over-fitting and leaving line texture on the image. Therefore, the proposed method provided more accurate and reliable information for the further analysis of topographic images, and it’s a more effective background subtraction method of TERS topography imaging.
		2018 Vol. 38 (02): 394-400 [Abstract] ( 161 ) RICH HTML PDF (5193 KB) ( 116 )

	401	The Controllable Synthesis and Luminescent Properties of ScF₃, NaScF₄, (NH₄)₂NaScF₆ Nanaocrysals
		ZHANG Li-gang^1，2, ZHAO Su-ling^1*, XU Zheng¹, ZHU Wei¹, BAI Yong-qing², QU Jiao², FAN Hong²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0401-06
		Scandium fluoride possess chemical stability, with low phonon energy and low potential cytotoxicity, is a new type of high efficient based material, and also distance between Sc³⁺-Sc³⁺ ions is also lower. Thus it has more peculiar physical and chemical properties, recently. Recently, Scandium fluoride codoped with Yb³⁺/Er³⁺have attracted significant interest and become study hot fields. In the paper, using Polyetherimide (PEI) as surfactant, a series ScF₃∶Yb³⁺/Er³⁺, NaScF₄∶Yb³⁺/Er³⁺, (NH₄)₂NaScF₆∶Yb³⁺/Er³⁺ nanocrystals were prepared at 200 ℃ by a facile hydrothermal method. By X-ray diffraction (XRD), Transmission electron microscopy (TEM), Scanning electron microscope (SEM) and fluorescence spectrometer, the crystal phase, morphology and luminescent characteristics of prepared samples were investigated. The results showed that the product, phase and morphology of sample can be tailored through varying the ratio of NH₄F/Ln³⁺ (NH₄F/Ln³⁺=1∶1, 2∶1, 2. 5∶1, 3∶1, 4∶1, 6∶1, 10∶1, 20∶1, 30∶1, 40∶1, 50∶1). When the NH₄F/Ln³⁺ ratio were 2.5∶1, the pure cubic phase ScF₃ was obtained. When NH₄F∶Ln³⁺ ratio was 4∶1, the hexagonal phases NaScF₄ was obtained. When the NH₄F∶Ln³⁺ ratio was 40∶1, the products were changed to pure cubic phase (NH₄)₂NaScF₆. The TEM and the SEM showed that the crystallinity of samples was high and the particle size was uniform. The morphology were square nano piece and polyhedron of football shape in different ratio of NH₄F/Ln³⁺. Meanwhile, the UC fluorescence emission spectra were measured. The color of UC emission were tuned from orange to red, green and yellow in samples by adjusting the ratio of NH₄F/Ln³⁺. It turned out that just change NH₄F one raw materials dosage, can generate ScF₃∶Yb³⁺/Er³⁺, NaScF₄∶Yb³⁺/Er³⁺, (NH₄)₂NaScF₆∶Yb³⁺/Er³⁺ three different kinds of products, which illustrate that NH₄F dosage has decisive effect to the type of products. The UC emission intensity and out colour can be also significantly influenced by the ratio of NH₄F/Ln³⁺.
		2018 Vol. 38 (02): 401-406 [Abstract] ( 206 ) RICH HTML PDF (3896 KB) ( 200 )

	407	FTIR Spectra and LA-ICP-MS Research of Growth Zones in Sapphire Bands from Changle, Shandong Province
		LI Xiao-xiao¹, YANG Zhi-jun^{1, 2*}, HUANG Shan-shan¹, CHEN Yao-ming¹, ZENG Xuan¹, ZHOU Wen-xiu¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0407-06
		The results of micro-infrared spectra and LA-ICP-MS research of growthzones in sapphire showed that there was an internal relationship between the formationof color of growth zone and —OH content in sapphire. In the sapphire which contained hexagonal growth zones, the content of —OH was similar in the same zone and varied from zone to zone. The content of —OH decreased gradually from dark growth zone to light growth zone. The content of —OH depended on the content of trace element Ti in the zones, which suggested that the content of —OH in the growth zones could be used to reflect the change rules of the formation process of sapphire. In the higher hydrogen condition, more Ti⁴⁺/Fe²⁺ substituted Al³⁺ into the sapphire crystal lattice. Otherwise, less or no Ti⁴⁺/Fe²⁺ substituted Al³⁺ into the sapphire crystal lattice. Therefore, systematic research of the distribution characteristic of —OH in the sapphire will be conducive to the formation mechanism of color of sapphire and provide new scientific ideas for high quality sapphire synthesis and optimization.
		2018 Vol. 38 (02): 407-412 [Abstract] ( 223 ) RICH HTML PDF (2206 KB) ( 161 )

	413	Research on Image Data Matching Method Based on Infrared Spectrum Technology of UAV
		TAN Xiang^{1, 2}, MAO Hai-ying², ZHI Xiao-dong³, HU Xing-bang¹, MA Ai-nai¹, YAN Lei^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0413-05
		UAV loading infrared/near-infrared spectroscopy on regional image acquisition load has become an important field of remote sensing technology, through classifying the position information of the portable image, and getting the vegetation cover, temperature index and a series of factors. In this paper, we used FREE BIRD low altitude unmanned aerial vehicle (UAV) to mount Tetracam- infrared camera (3 million 100 thousand pixels) to get the image of a river in Xinjiang, Manasi. In order to get more accurate vegetation temperature and other factors, we needed UAV infrared/near infrared image registration, through the optimization of SIFT, detection of outliers and RANSAC parameters, to obtain reliable matching results. After the matching algorithm of the image ,the original image of the error ratio were below 60%, which was one of the innovations of this paper to meet the needs of the application. After registering the images, the images were spliced, and the infrared images were spliced according to the degree of overlap of the course of not less than 60%, while the probability of the adjacent overlap was not less than 50%. At the same time, this paper compared the SIFT and SUFT two kinds of algorithms, using FLIR sensor SIFT algorithm and improved optimization to obtain 1 600 thermal infrared image matching and image inversion of ground by utilization of synchronous measurement data. We used ENVI software to carry out the inversion of vegetation coverage temperature inversion and inversion vegetation map to get the single image and the infrared image of the study area. The algorithm model is more optimized through the comparison of the two algorithms, while the model of regression analysis and test of accuracy, the correlation coefficient R² of the model is 0.767, and accuracy is 81.51% with higher model precision. This model provides theoretical and practical basis for the registration and extraction of inversion of UAV infrared image.
		2018 Vol. 38 (02): 413-417 [Abstract] ( 220 ) RICH HTML PDF (2603 KB) ( 322 )

	418	Study of Mechanism of Aluminum Sizing Precipitant on Xuan Paper Based on Spectral Analysis
		HE Qiu-ju^1，2, WANG Li-qin^1*, ZHANG Ya-xu¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0418-06
		In order to investigate the action mechanism of aluminum salts in the process of surface sizing of Xuan paper used in painting and calligraphy，the aluminum species distribution of Alum，polyaluminum chloride (PAC) and polyaluminum sulfate (PAS)，which were commonly used as sizing precipitant，in aqueous solution and mixed with gelatin on the surface of Xuan paper were studied by Al-Ferron complex timed spectrophotometric method (Al-Ferron)，high-field ²⁷Al-NMR spectroscopy (²⁷Al-NMR) and attenuated total reflection infrared spectroscopy (ATR-FTIR) for the first time. (1) Al-Ferron and ²⁷Al-NMR analysis showed that the hydrolysis products of alum and PAS solution were mainly monomeric aluminum Al(H₂O)³⁺₆(Al1)，AlSO⁺₄ and polymeric aluminum[Al₃₀O₈(OH)₅₆(H₂O)₂₄]¹⁸⁺(Al₃₀)；except for Al₁ and Al₃₀，polymeric aluminum [AlO₄Al₁₂(OH)₂₄(H₂O)₁₂]⁷⁺(Al₁₃) was also existed in PAC solution；(2) ²⁷Al-NMR analysis showed that the peaks of monomeric and polymeric aluminum were weakened significantly with the combination of aluminum salt and gelatin，and the results of ATR-FTIR showed that the reduced positive hydrolyzed products were probably bonded with hydroxyl (—OH) or carboxyl (—COOH) from gelatin. The tight network structure they formed could improve the crosslinking and water-resistance of the glue. Meanwhile，as a role of precipitants，aluminum hydrolyzed products could transform negative gelatin particles into positive charge，prompting gelatin particles deposited on the negatively charged fibers. After sizing, the hydroxyl groups, some amino and carboxyl groups of gelatin collagen could form many hydrogen bonds with the carboxyl groups in the non ionic region of the plant fibers, so the water resistance of the Xuan paper was improved obviously. In summary，as an effective means to study sizing mechanism，the combination of Al-Ferron，high-field ²⁷Al-NMR and ATR-FTIR technology can rapidly reveal the chemical structure changes of aluminum salts in paper sizing process.
		2018 Vol. 38 (02): 418-423 [Abstract] ( 218 ) RICH HTML PDF (2450 KB) ( 254 )

	424	Rapid Detection of Lotus Seed Powder Based on Near Infrared Spectrum Technology
		FU Cai-li¹, LI Ying¹, CHEN Li-fan¹, WANG Shao-yun¹, WANG Wu^2*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0424-06
		Lotus seed is an important medicine and edible food, but to dry lotus seeds cook requires a long time, so lotus seed powder is more popular by consumers to adapt to the modern fast-paced way of life. In this paper, lotus seed powder adulterated with sweet potato powder, corn flour and wheat flour were identified by near infrared spectroscopy (NIRs) technique. Support vector machine (SVM), least squares support vector machine (LS-SVM) and partial least squares discriminate analysis (PLS-DA) were used to identify the model when thecategory was known, and the clustering algorithm was usedotherwise. In addition, the moisture content of lotus seeds powder was quantitatively analyzed by partial least squares (PLS) regression. The results showed that the discrimination accuracy of LS-SVM modelis 100%, and the clustering algorithm could effectively identify the 5% adulteration ofsweet potato powder, corn flour and wheat flour. Moreover, performance of PLS model to predict the moisture content in the lotus seed powder is good, and the accuracy of model by Normalize was satisfactory with the coefficients of determination of calibration (R²_c=0.973 2), the coefficients of determination of prediction (R²_p=0.969 5), root mean square errors of calibration (RMSEC=0.111 5), and good root mean square errors of prediction (RMSEP=0.118 9). The results showed that the near infrared spectroscopy is a fast, accurate and nondestructive analysis method to rapidly identify the lotus seed powder, accurately determinate the water content in lotus seed powder, and availably provide a useful idea for quality testing of daily food.
		2018 Vol. 38 (02): 424-429 [Abstract] ( 279 ) RICH HTML PDF (3116 KB) ( 601 )

	430	Detection of Early Tiny Bruises in Apples using Confocal Raman Spectroscopy
		CHEN Si-yu¹, ZHANG Shu-hui², ZHANG Shu¹, TAN Zuo-jun^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0430-06
		Mechanical damage of apple can result from compression, vibrations and collisions during harvesting, handling, transport operation and storing process. The part of tiny bruise apple is unable to be identified by the naked eye and is more likely to be invaded by micro-organism and pathogen, which will not only cause the affected fruit to rot, but will also affect other intact fruit. Therefore, it is significant for the postharvest treatment and storage to a identify the early tiny bruise of apple quickly and accurately, which can reduce economic losses. Raman spectroscopy combined with chemometric methods was used to rapidly classify apple flesh with early tiny bruising. SG (Savitzky-Golay) was used to smooth spectroscopy. AirPLS (adaptive iteratively reweighted penalized least squares) was used to correct the baseline of spectroscopy. After using KS method to divide training set and verification set, classified models were developed with non-linear support vector machine (SVM) regression which were based on the linear and polynomial kernel functions. The classification accuracy rate was 97.8%. The results showed that Raman spectroscopy combined with chemometric methods can quickly identify the early tiny bruise of apple, demonstrating the application prospect of Raman spectroscopy to discriminate the early tiny bruise apple.
		2018 Vol. 38 (02): 430-435 [Abstract] ( 341 ) RICH HTML PDF (3542 KB) ( 287 )

	436	Wavelength Selection by siPLS-LASSO for NIR Spectroscopy and Its Application
		MEI Cong-li^1，2, CHEN Yao², YIN Liang², JIANG Hui², CHEN Xu², DING Yu-han², LIU Guo-hai²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0436-05
		Near-infrared spectroscopy (NIR) is widely used in entire production processes and product quality test, especially in food and drug industries. It has many advantages, e. g. no requirement of sample pretreatment, low cost, non-destructive detection, and fast determination. However, the application of the whole spectrum data in modeling can lead to complexity and poor stability. The synergy interval PLS(siPLS) is the most common dimensionality reduction method for spectral data. However, it cannot deal with the collinearity problem of spectral data. Least absolute shrinkage and selection operator (LASSO) is a relatively new method for data dimensionality reduction. However, when it comes to small samples, its instability cannot be ignored. For disadvantages of siPLS and LASSO in NIR calibration, a novel wavelength selection method named siPLS-LASSO was proposed. It was validated in a wheat-straw solid-state fermentation process by monitoring pH values. In the method, siPLS was firstly used to selected intervals of NIR spectroscopy. Secondly, LASSO was used to select wavelengths on the selected intervals. Finally, the selected wavelengths were used to construct PLS model for prediction. For comparisons, several conventional wavelength selection methods were also studied. In the case study, 33 wavelengths were eventually selected by the siPLS-LASSO method and used for PLS modelling. The RMSEP and Rp of the model were 0.071 1 and 0.980 8 respectively. Results showed that the proposed siPLS-LASSO was an effective method of wavelength selection and can improve prediction performance of models.
		2018 Vol. 38 (02): 436-440 [Abstract] ( 221 ) RICH HTML PDF (1236 KB) ( 327 )

	441	Derivatization Enhanced Raman Characteristic Vibration Spectrum of PAEs Based on Pharmacophore Model
		QIU You-li^1,2, XIN Mei-ling^1,2, LI Yu^1,2*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0441-07
		In this paper, 3D QSAR pharmacophore models of PAEs Raman characteristic vibration spectrum were established by Discovery Studio software for 17 phthalic acid esters were used as training set and 5phthalic acid esters used as test set. The substitution reaction of PAEs (take environmental priority controlled pollutants DMP, DBP and DNOP for example) used the optimal pharmacophore model built by Hypo 1 and 9 kinds of common hydrophobic groups. At the same time, the Raman characteristic vibration spectrum of PAEs and derivatives in gaseous environment were calculated by using density functional theory at B3LYP/6-31g(d) level, which was to screen derivative reaction of PAEs Raman characteristic vibration spectrum enhanced significantly. The results showed that the pharmacophore model (Hypo 1) was significant and had good predictive abilities with the greatest correlation coefficient (R²) of 0.83, the smallest value of root mean square (RMS) of 0.182 and the total cost of 71.865, the configuration value of 12.68 (<17). There were 23PAEs derivatives based on Hypo 1, including 9 DMP derivatives, 9 DBP derivatives, 5 DNOP derivatives, and the positive frequencies of derivative molecules were greater than 0, which illustrate the structure of PAEs derivatives were stable. The Raman characteristic vibration spectrum intensity of DMP-CH₂CH₃, DBP-Cl, DNOP-C₆H₅ increased comparing with DMP, DBP, DNOP by 6.25 times, 2.05 times and 1.56 times respectively, which indicated that PAEs derivatization had significantly enhanced effect on Raman characteristic vibration spectrum intensity. In addition, the substitution reaction energy barriers of PAEs derivatives were calculated by using density functional theory at B3LYP/6-31g(d) level, (take DNOP for example), and the substitution reaction order of the substituent —C₆H₅, —CH₂CH₂CH₃, —SH, —Cl, —NO₂ and DNOP molecule was —CH₂CH₂CH₃>—C₆H₅>—NO₂>—SH>—Cl, which can be uesd as the basis of screening PAEs molecular derivatization enhanced Raman spectrum reaction and provide theoretical support for the enhanced Raman spectrum detection technology.
		2018 Vol. 38 (02): 441-447 [Abstract] ( 188 ) RICH HTML PDF (2176 KB) ( 149 )

	448	Essential Oils of Zingiberaceae Alpinia Kwangsiensis and Achasma Yunnanensis in Situ Research with Raman
		SI Min-zhen^{1, 2}, ZHANG De-qing^{1, 2}, LI Lun^{1, 2}, ZHANG Chuan-yun^{1, 2}
		DOI: 10.3964/j.issn.1000-0593(2018)02-0448-06
		Non-destructive analysis of the essential oils ingredient in oil cells at room temperature was presented. This work showed the possibility to detect in situ the main components of the essential oils in Alpinia kwangsiensis and Achasma yunnanensis oil cells by means of Raman spectroscopy. Water slice of fresh samples were prepared. The oil cells in water slice can be seen using 20 objective lens of DXR Laser confocal micro Raman spectrometer. At the Alpinia kwangsiensis oil cell, high intensity bands were present in 1 638，1 600，1 555，1 203，1 001 cm^-1，and low intensity bands were present in 1 716，1 577，1 496，1 407，1 346，1 307，1 273，1 181，1 156，1 029，958，618，218 cm^-1. Together 26 spectroscopic bands were obtained. The Raman spectrum of the Methyl cinnamate, together 29 spectroscopic bands, were obtained. It was found that the 22 presented spectroscopic bands of Alpinia kwangsiensis oil cell correlated very well with those obtained by the Methyl cinnamate；At the Achasma yunnanensis oil cell, high intensity bands were present in 1 648，1 639，1 607，1 174，842，836 cm^-1，and low intensity bands were present in 1 292，1 244，1 235，1 204，631 cm^-1. Together 24 spectroscopic bands were obtained. The Raman spectrum of the 4-Allyl anisole, together with 29 spectroscopic bands(between 300～1 700 cm^-1) was obtained. It was found that the 23 presented spectroscopic bands of Achasma yunnanensis oil cell correlated very well with those obtained by the 4-Allyl anisole. The experimental work was supported by quantum chemical calculations at the B3LYP/6-311G level of theory. The essential oils ingredient in oil cells of Zingiberaceae samples can be detected directly and quickly without extraction. This method can be use to quality control and development research for zingiberaceae plant essential oil extraction.
		2018 Vol. 38 (02): 448-453 [Abstract] ( 228 ) RICH HTML PDF (2131 KB) ( 201 )

	454	Dynamic Surface-Enhanced Raman Spectroscopy for Rapid and Quantitative Analysis of Edifenphos
		WENG Shi-zhuang¹, YUAN Bao-hong², ZHENG Shou-guo³, ZHANG Dong-yan¹, ZHAO Jin-ling¹, HUANG Lin-sheng^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0454-05
		Dynamic surface-enhanced Raman spectroscopy (SERS) is based on thestate transition of nanostructure from wetstate to dry state to realize spectra measurement, and it not only produces giant Raman enhancement but also provides reproducible and stable SERS signal. In the paper, we proposed a novel method for the rapid and quantitative analysis of edifenphos based on dynamicsurface-enhanced Raman spectroscopy with multivariate analysis method. In experiment, the spectra of 100, 50, 10, 5, 1, 0.5 and 0.1 mg·L^-1edifenphos were measured using dynamic surface-enhanced Raman spectroscopy, and the baseline shift of spectra was removed by the polynomial correction method. Then, the spectra of full range (600~1 800 cm^-1) and characteristic range (674~713，890~1 195，1 341~1 399 and 1 549~1 612 cm^-1) were used to develop the regression model for the rapid and quantitative analysis ofedifenphos using support vector machine regression (SVR), respectively. Simultaneously, we also evaluated the effect of the principle component analysis (PCA) on the construction of the regression model. The experiments showed the model developed with the spectra of characteristic range had lower prediction error and PCA can improve the prediction accuracy of the corresponding model further. The best regression model (RMSECV=0.065 7 mg·L^-1) was built with the spectra of characteristic range extracted by PCA, and the regression model can predict the concentration of edifenphos solutions accurately. Finally, to evaluate the effect of the method in practical application, the edifenphos residue on the apple peel were also detected using the proposed method, which was compared with the gas chromatography. The detection results showed the multiple detection value for each sample was in a small range, and the mean value was basically consistent with the detection value of gas chromatography, in which the maximal relative error was about 5.13 %. Additionally, the detection process of dynamic surface-enhanced Raman spectroscopy only needed 2 min and 2 μL samples volume, and the subsequent data analysis generally consumed several seconds. In a word, the dynamic surface-enhanced Raman spectroscopy can provide the high reproducible and precision detection of edifenphos, and the multivariate analysis method can realize the intelligent and rapid analysis of Raman spectra of edifenphos. Therefore, the dynamic surface-enhanced Raman spectroscopy with the multivariate analysis method is of great advantage for the rapid and accurate detection of edifenphos.
		2018 Vol. 38 (02): 454-458 [Abstract] ( 212 ) RICH HTML PDF (2498 KB) ( 150 )

	459	Discrimination of Human, Dog and Rabbit Blood Using Raman Spectroscopy
		DONG Jia-lin¹, HONG Ming-jian^{1, 3*}, ZHENG Xiang-quan^{2, 3}, XU Yi^{2, 3}
		DOI: 10.3964/j.issn.1000-0593(2018)02-0459-08
		The identification of multiple species blood is particularly important for entry-exit inspection and quarantine, forensic investigation and wildlife protection. The traditional methods often destroy blood samples and make further analysis of samples impossible. Raman Spectroscopy is a vibrational spectrum, which can obtain the information of molecular vibration and rotation so as to analyze the chemical composition of the material. It provides the possibility of non-destructive blood identification. Currently, there are several methods of blood identification based on Raman spectroscopy, but these methods use the linear classification model, ignoring nonlinear relationship between the spectrum and sample, and lead to the bad performance of the model. Moreover, the small sample number of each species usually results in the under-fitting the model. Therefore, this paper set up a classification model for the nonlinear relationship using the support vector machine to identify Raman spectra of blood, overcame the shortcoming of the linear classification model which emphasizes the linear characteristic of the spectrum in the training, and absorbed the nonlinear relationship in the Raman spectrum effectively, realizing the three classification of human, dog and rabbit blood. There are a total of 326 samples which were measured by Ocean Raman spectrometer with excitation wavelength of 785 nm, including 110 humans, 116 dogs and 100 rabbits. Savitzky-Golay smoothing filter, weighted least squares baseline correction, and vector normalization were used to preprocess them. The 2/3 of these samples were used as calibration set for training and the remaining samples were used as test set for blind testing. Experimental results showed that the classification accuracy of proposed model for the calibration set and the blind test were 100% and 93.52%, and outperformed the existing linear classification models. This indicates that proposed classification model has good application prospects and research value.
		2018 Vol. 38 (02): 459-466 [Abstract] ( 237 ) RICH HTML PDF (6289 KB) ( 200 )

	467	Polarization Characterization of Laser-Induced Fluorescence from the Simulated Oil Samples Based on Polar Decomposition of Mueller Matrix
		LUAN Xiao-ning¹, ZHANG Feng¹, GUO Jin-jia¹, CUI Ting-wei², ZHENG Rong-er^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0467-08
		By refering to the principle and structure of the Mueller matrix ellipsometry, a LIF ellipsometric setup with rotating waveplate was built up to investigate the polarization characterization of laser-induced fluorescence from the simulated oil spill samples under excitation of laser with different elliptical polarization states. The setup was calibrated with the Eigenvalue Calibration Method at first to obtain the exact modulation states of both the polarization modulation matrix W(λ) and the polarization analyses matrix A(λ). Then with the fluorescence intensity matrices Flu(λ) measured by sequentially modulation of the polarization-state generator unit and the polarization-state analyzer unit, LIF Mueller matrices of light, medium and heavy crude oil samples as well as diesel were established and analyzed via polar decomposition. It was found that the depolarization properties of fluorescence spectrum from different samples were of significant differences. The depolarization coefficient extracted from the LIF Mueller matrix from diesel varied little with the wavelength increasing, which maintained a high degree of depolarization value within the whole spectral range, while those from other three crude samples kept rising under the same circumstances. With respect to the variation amplitude of the depolarization coefficient, the medium crude sample exceeded the heavy crude but was inferior to the light one. Among the four simulated oil samples, the depolarization coefficient extracted from LIF Mueller matrices from light crude and heavy crude samples were highest and lowest respectively, while those from diesel and medium samples lied between them. Compared to the results of LIF orthogonal polarization experiment under linearly polarized excitation, the depolarization coefficients Δ(λ) extracted from polar decomposition of LIF Mueller matrices were highly relevant to those DODP obtained from orthogonal polarization characterization of fluorescence spectrum of the simulated oil samples. And it was also found that both the diattenuation and retardation properties of the fluorescence spectrum from the simulated oil samples were very weak and showed little differences.
		2018 Vol. 38 (02): 467-474 [Abstract] ( 247 ) RICH HTML PDF (6390 KB) ( 182 )

	475	Research of Identification Method for the Oil Spills Species Based on Fluorescence Excitation-Emission Matrix and Parallel Factor Analysis
		ZHOU Yan-lei¹, ZHOU Fei-fei¹, JIANG Cong-cong¹, SHI Xiao-yong^1，2*, SU Rong-guo¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0475-06
		Accidental oil spills occur frequently around the world and they can have serious influence on the human health and the ecosystem due to the compounds in oil. Thus, there is an urgent need for an accurate method for determining the source of spills. In order to meet the rapidly demand identifying methods of oil spills, this paper utilized parallel factor analysis to develop an identification method for the crude oils and fuel oils based on their fluorescence excitation-emission matrixes. Firstly, the fluorescence excitation-emission matrixes of six kinds of crude oils (Roncador crude oil, Basra crude oil, Russian crude oil, Saudi crude oil (heavy crude oil), Upper Zakum crude oil, sea two station crude oil) and three kinds of fuel oils (380 CST fuel oil, Fuel oils No.5—No.7, LanShan fuel oil) were normalized after removing scatter by Blannany triangulation with linear interpolation. Afterwards, the parallel factor analysis was used for the fluorescence excitation-emission matrixes. Seven factors can be reliably extracted from the data set, and then seven fluorescence components were obtained, which made up the characteristic spectrum. By clustering analysis and Bayesian Discrimination of the characteristic spectrum from the samples that had experienced weathered for 3, 15 and 45 days and not experienced weathered, the capacity of the oil fluorescence spectrum analysis was determined and the fluorescence feature spectra library consisted of 12 standard fluorescence spectra of crude oils and 6 standard fluorescence spectra of fuel oils was established. In the end, multiple linear regression was used to recognize the samples that had experienced weathered for 0, 7 and 30 days by the oil standard fluorescence spectra. The results showed that, except for Russian crude oil, the method could clearly classify 5 kinds of crude oils and 3 kinds of fuel oils which had experienced weathered and had not experienced. Furthermore, the accuracy of the identification for crude oils and fuel oils were 100.0%, and the overall accuracy of the identification for crude oils and fuel oils were 87.5% and 100%, respectively.
		2018 Vol. 38 (02): 475-480 [Abstract] ( 231 ) RICH HTML PDF (3238 KB) ( 375 )

	481	The Preliminary Study on the Relationship between Two Dimensional Fluorescence Peak Value of Surface Water and Water Quality Indexes in Ebinur Lake Basin
		ZHANG Xian-long^{1, 2}, ZHANG Fei^{1, 2, 3*}, ZHANG Hai-wei^{1, 2}, HAI Qing⁴, CHEN Li-hua⁵
		DOI: 10.3964/j.issn.1000-0593(2018)02-0481-07
		With the progress and development of technology, domestic and foreign scholars have already made a lot of researches on the evaluation and estimation of water quality indexes by different technical means. However, the method of estimating water quality by using two-dimensional fluorescence peak value is still rare. The paper took the surface water of Ebinur Lake basin as the research object, using multivariate statistical analysis and stepwise regression analysis method, and explored the interrelationship of two-dimensional fluorescence peak value and water quality indexes by establishing an estimation model. The results showed that: (1)The water quality was different for the different river of Ebinur Lake basin, the total nitrogen(TN) content of Bortala River was the highest, and the total phosphorus(TP) content of reservoir and canal were the highest. (2)The same water sample has three fluorescence peaks (Peak1, Peak2, Peak3), and the fluorescence peak intensity gradually weakened. The intensity of two-dimensional fluorescence peak value in different rivers was different, among them, the variation range of fluorescence intensity in Bortala River，reservoir and canal were the highest. (3)The correlation analysis between two-dimensional fluorescence peak value and water quality indexes showed that Peak1 and five days biochemical oxygen demand(BOD₅), Peak2 and BOD₅, Peak2 and chemical oxygen demand(COD), Peak2 and dissolved oxygen(DO) both had good correlation, and the correlation coefficient was 0.479, 0.371, 0.655 and 0.618 respectively. The estimation model was established by the single fluorescence peak value and water quality indexes, which could not meet the monitoring requirements, because the poor accuracy of the four models were verified. Therefore, based on the single fluorescence peak value model, we established a integrated model of the three peaks and water quality indexes of each water sample for obtaining multiple regression equation. We found that the integrated model of the three groups of fluorescence peak and DO had the best effect through the model validation, the Correlation Coefficient was 0.756, and the Root Mean Square Error was 1.001. Therefore, the synthetic estimation model of two-dimensional fluorescence peak value and water quality indexes is feasible, which has a certain reference for the monitoring of water quality in arid area, and provides scientific basis for the development, utilization and protection of water resources in the Ebinur Lake basin.
		2018 Vol. 38 (02): 481-487 [Abstract] ( 173 ) RICH HTML PDF (3316 KB) ( 87 )

	488	The Study of Hydrothermal Conditions’s Impact on the Structure of Black Soil Fulvic Acid Based on the Fluorescence Spectral Characteristics
		GU Si-yu, LI Yue, CAI Yue-tong, GUO Xing-jun, ZHU Yu-wei, YU Xue-wei, YANG Yan, ZHANG Hui-hui^*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0488-06
		In order to understand the influence of hydrothermal conditions to the humification degree of fulvic acid in field black-soil, four samples Beian, Hailun, Binxian and Shuangcheng which were taken from four typical black soil regions in Heilongjiang, China, were selected for this study. In this study, the fulvic acid substances in these samples were extracted, and characterized their fluorescence properties. The results showed that, from north to south , as the increase of hydrothermal distribution, the concentration of fulvic acid substances, in Beian，Hailun，Binxian and Shuangcheng, presented a decrease trend. And the amount of the decrease were 9.90，8.71，5.48 and 4.70 g·kg^-1, respectively. Humic acid and fulvic acid ratio is on the decline were 1.46，1.42，0.80 and 0.74 in turn, Higher proportion of fulvic acid leading to Humus structure tends to be more simple. The results of excitation-emission matrix regional integration analysis further confirmed that the intensity of fluorescence peak A and peak C in Beian presented the highest values and intensity of fluorescence peakA and peak C in Shuangcheng presented the lowest values in these four study regions. Compared with Beian, Hailun and Binxian study regional intensity of fluorescence Peak C was lower, and Regional integration (FRI) method showed that, from north to south, as the increase of hydrothermal distribution，visible light area like fulvic acid material significantly reduced; Parallel factor analysis (PARAFAC) results showed that the fulvic acid substances in these four study regions could be divided into two components. Component C1 was characterized as simple structure and low molecular weights substances, and Component C2 was regarded as complex structure and high molecular weights substances. With the increase of hydrothermal distribution , Component C1 was on the rise and Component C2 presented a decrease trend. The increase of Component C1 mainly came from the degradation of the intermediate of Component C2, and a higher proportion of Component C1 promoted the decomposition of FA in the soil. Two-dimensional synchronous scanning map showed that the lower latitude, the simpler structure of humic presented. FA in the black-soil, larger molecular weight and structure of complex material priority cracked form a simple structure relatively, high condensation degree of small molecular compound, and then decomposed completely. Based on the results above, a conclusion could be concluded, that hydrothermal conditions have disadvantage for accumulation of FA substances in black-soil.
		2018 Vol. 38 (02): 488-493 [Abstract] ( 256 ) RICH HTML PDF (4780 KB) ( 341 )

	494	We studied on the Intermolecular Interaction between Perfluorooctanoic Acid and Serum Protein by UV-Fluorescence Spectrometry and the Establishment of the Theoretical Models
		WANG Yan¹, Lü Da², GUO Ming^{1, 3*}, ZHAO Xiao-xue¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0494-08
		Study on the establishment of intermolecular interaction between perfluorooctanoic acid (PFOA) and human serum protein (HSA) and its theoretical modeling. Fluorescence spectrums combined with ultraviolet spectrum have been studied the intermolecular interaction between PFOA and HSA to obtain PFOA-HSA ultraviolet-fluorescence spectrum features. The UV-fluorescence characteristic spectra showed that PFOA regularly decreased the UV absorption and fluorescence intensity of HSA, and the maximum emission wavelength of HSA caused obvious blue shift, which indicated that there was intermolecular interaction between PFOA and HSA. The binding constants between PFOA and HSA were obtained by analyzing spectrum experiments data, which indicated the medium intermolecular interaction between PFOA and HSA. On the basis of Van’t Hoff equation to analyze spectrum experiments datas to attain the thermodynamic parameters of the intermolecular interaction between PFOA and HSA. The obtained thermodynamic parameters were ΔH>0, ΔS>0, ΔG<0, which indicated that the main forces between HSA and PFOA were hydrophobic force and hydrogen bond by Ross theories, and the intermolecular interaction between HSA and PFOA was spontaneous process. Synchronous fluorescence spectrum revealed that the intermolecular interaction of PFOA and HSA resulted in a change in the microdomain conformation of the serum protein molecule, which changed the conformational domain of the tryptophan residue. In this paper, the polarizing factor M was proposed to quantitatively characterize the interaction between PFOA and HSA by fluorescence polarization spectroscopy. Based on spectral data analysis, the theoretical model of the interaction between PFOA and HSA was established, The theoretical model results showed that the intermolecular interaction of PFOA and HSA occured mainly in the HSA active site Ⅰ region and the intermolecular interaction between HSA and PFOA was a spontaneous process. The results of spectral experiments were basically consistent with the theoretical modeling results. These data can provide a useful reference for a comprehensive understanding of the intermolecular interactions between biological macromolecules and perfluorinated compounds and the study of microscopic toxicological mechanisms.
		2018 Vol. 38 (02): 494-501 [Abstract] ( 216 ) RICH HTML PDF (3611 KB) ( 129 )

	502	The Fluorescnece Lifetime and Quantum Chemistry Calculation of Ethyl Caproate and Ethyl Acetate
		ZHANG Xiao-he^{1, 2}, MA Chao-qun^{1, 2*}, CHEN Guo-qing^{1, 2}, LIU Huai-bo^{1, 2}, ZHU Chun^{1, 2}, SONG Xin-shu^{1, 2}, ZHU Cong-hai^{1, 2}
		DOI: 10.3964/j.issn.1000-0593(2018)02-0502-04
		This paper presents a method for quantitative analysis of the volume ratios of various substances in mixtures using fluorescence lifetime. The two kinds of fluorescent materials, ethyl caproate and ethyl acetate, were selected as standard samples. The spectral overlap of thyl caproate and ethyl acetate was 78%. For materials with high overlap of fluorescence emission spectra, it was difficult to make quantitative analysis with the combination of ordinary fluorescence with algorithm, because their overlap of fluorescence emission spectra was serious. The molecular structure of the two substances was quantified by quantum chemistry. The life time of ethyl caproate was 1.0 ns and the ethyl acetate was 5.3 ns. However, their fluorescence decay curves were obviously different. Therefore, this paper did quantitative analysis to them through time resolved fluorescence spectrometry. By analyzing the change trend of the fluorescence lifetime curve of the two substances at different volume ratios, a prediction model of fluorescence lifetime and volume ratio of two substances was established and tested. The experimental results showed that the method can achieve the measurement of the volume ratio of the mixed solution, and the mean residuals were controlled within 1%, which had certain practical value.
		2018 Vol. 38 (02): 502-505 [Abstract] ( 305 ) RICH HTML PDF (2222 KB) ( 460 )

	506	Research on Threshold Improved Denoising Algorithm Based on Lifting Wavelet Transform in UV-Vis Spectrum
		ZHOU Feng-bo^{1, 3}, LI Chang-geng¹, ZHU Hong-qiu^2*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0506-05
		In the quantitative analysis of UV-Vis spectroscopy, the random noisewhich affects the accuracy of the spectral quantitative analysis resultsseriously, is caused by spectrophotometer internal optical systems, light sources, detectors, electronic components, circuit design and external environmental interference and other factors. In order to improve the accuracy of UV-Vis spectral analysis, the spectral data need to be denoised firstly. Because wavelet analysis has the characteristics of multiresolution, low entropy and decorrelation, the denoising algorithm based on wavelet transform is superior to the traditional denoising algorithm. Currently there are threshold denoising method, coefficient correlation denoising method and modulus maxima denoising method in wavelet transform domain. In these method，the threshold denoising method proposed by Donoho is the most commonly used in engineering application. According to Donoho threshold denoising principle, this paper proposes a threshold improved algorithm based on lifting wavelet transform. On the one hand, the lifting wavelet transform is the second generation wavelet transform, inherits the multi-resolution characteristic of the wavelet transform, and does not need the Fourier transform, which has the characteristics of small computation, fast speed and simple realization. On the other hand, a new threshold function is proposed to overcome the discontinuous shortcoming in the hard threshold method and reduce the constant deviation in the soft threshold method. At the same time, the threshold estimation is adjusted to facilitate the retention of the signal wavelet coefficients and the elimination of the noise wavelet coefficients. The UV-Vis spectrum of three groups poly-metal ions were used to test the performance of the proposed denoising method. In the experiment, random noise was first added to the spectrum, and then removed by the proposed denoising method. The signal to noise ratio(SNR) and the root mean square error(RMSE) were used to evaluate the performance of the proposed denoising method. The experimental results showed that the proposed method was superior to the soft threshold method and the hard threshold method in improving SNR and decreasing RMSE, which can effectively eliminate the spectral noise and keepsome important detail features in the spectral signal. So, this proposed method is more suitable for the denoising pretreatment before the UV-Vis spectral data modeling, and will have a good application prospect in UV-Vis spectroscopic analysis.
		2018 Vol. 38 (02): 506-510 [Abstract] ( 284 ) RICH HTML PDF (2141 KB) ( 279 )

	511	Changes Analysis of Post-Fire Vegetation Spectrum and Index Based on Time Series GF-1 WFV Images
		SUN Gui-fen¹, QIN Xian-lin^1*, YIN Ling-yu¹, LIU Shu-chao¹, LI Zeng-yuan¹, CHEN Xiao-zhong², ZHONG Xiang-qing²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0511-07
		To explore the ability of domestic high-resolution satellite remote sensing technology monitoring the effect of fire disturbance on vegetation growth and the characterize vegetation index, two burned sites formed by forest fire in 2014 in Yajiang county and Mianning county of Sichuan province were selected as the study area. The change of vegetation spectral features of burned area at different burned severity between pre-fire and post-fire has been analyzed using the selected GF-1 WFV data. At the same time, post-firetime series GF-1 WFV data has been used to analyze the monthly variation of Normalized Difference Vegetation Index(NDVI), Enhanced Vegetation Index (EVI) and Global Environment Monitoring Index (GEMI) which can characterize vegetation growth status of fire disturbance vegetation at different fire severity during two years after the forest fires taking place. With Combination of the latitude, altitude and climatic conditions of the study area, vegetation recovery pattern of post-fire vegetation was analyzed. Results showed that the vegetation pigments and cell structure were destroyed by the fire, which made its spectral features no longer show the unique spectral characteristics of normal vegetation. In the visible region, spectral reflectance of fire-disturbed vegetation at different fire severity was higher than that of normal vegetation and its value increased withthe severity. In the near infrared band, the reflectance of vegetation decreased after fire disturbance and its value was much lower than that of normal vegetation. NDVI, EVI and GEMI were highly correlated in the characterization of vegetation restoration process and sensitive to vegetation seasonal variation, which made it capability to reflect vegetation restoration process and they had the ability to describe the dynamic process of vegetation restoration. The changes of vegetation index of disturbed vegetation in vegetation restoration process were basically same as that of normal vegetation. Growing and non-growing season existed in the restoration process of affected vegetation as well. NDVI, EVI and GEMI of the vegetation at burned area were always lower than those of the normal vegetation and the higher the vegetation burned severity, the lower the vegetation index value was.
		2018 Vol. 38 (02): 511-517 [Abstract] ( 236 ) RICH HTML PDF (3259 KB) ( 357 )

	518	The Comparison of Inhibition on LDL Non-Enzymatic Glycosylation and Oxidation between Ethyl Acetate Extracts of Clove and Clove Bud Oil Based on Spectroscopy Technology
		XIE Zhi-yong^1,2, XIE Li-qin^1,2, JIANG Shen-hua^1,2,3*, QU Wen-juan^1,3, ZHANG Xiao-xia^1,2, ZHANG Hua-hao^1,2, HAO Shu^1,2, ZHANG Liang-hui^1,2, MA Hai-le^1,3, SHEN Yong-gen^1,4
		DOI: 10.3964/j.issn.1000-0593(2018)02-0518-10
		Non-enzymatic glycosylation and oxidation of low density lipoprotein (LDL) both have been crucial factors leading to atherosclerosis (AS). It was found in previous studies that clove had inhibitory effects on the glycosylationof bovine serum albumin (BSA) and high-density lipoprotein (HDL), while ethyl acetate extracts of clove (EAEC) and clove bud oil (CBO) had strong antioxidant activity. In order to determine the most effective components of clove to inhibit LDL from glycosylation and oxidation, the comparisons of inhibition between EAEC and CBO on LDLglycosylation and oxidation were studied in this paper on the basis of the previous studies based on spectroscopy technology. The glycosylation incubation system of LDL-glucose was firstly established in this experiment. The inhibition between EAEC and CBO on LDL glycosylation was compared by the determination of the products during the early, middle and the end periods of glycosylation, and the spectra variations of the three-dimensional fluorescence. Secondly, LDL-CuSO₄ as oxidation incubation system was established, and the inhibition between EAEC and CBO on LDL oxidation was compared by the determinations of fluorescence indicators and three-dimensional fluorescence spectroscopy, UV-Visible spectra. The results indicated that EAEC and CBO both have inhibition of the formation of Amadori, dicarbonyl compounds, AGEs and pentosidines which are products during the early, middle and the end period of LDL glycosylation respectively, and the inhibition effects of EAEC were stronger than those of CBO; three-dimensional fluorescence spectroscopy showed the same results as above. During LDL oxidation, the inhibition of CBO on tryptophan (Trp) fluorescence quenching, the formation of total fluorescence products and lipofuscin, lysine (Lys) modification were significantly better than those of EAEC; three-dimensional fluorescence spectroscopy showed the same results; CBO had stronger inhibitory effect than EAEC on conjugated diene (CD) generated and spectrum redshift in UV-Visible scanning spectra. This study provides a reference for further separation and purification of the key components, research anddevelopment of functional foods inhibiting LDL glycosylationand oxidation ofclove.
		2018 Vol. 38 (02): 518-527 [Abstract] ( 212 ) RICH HTML PDF (5866 KB) ( 133 )

	528	Study on the Quick Non-Destructive Detection of Citrus Huanglongbing Based on the Spectrometry of VIS and NIR
		LIU Yan-de¹, XIAO Huai-chun¹, SUN Xu-dong¹, HAN Ru-bing¹, YE Ling-yu¹, HUANG Liang¹, XIAO Yu-song¹, LIAO Xiao-hong²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0528-07
		Huanglongbing (HLB) is a devastating disease of citrus fruit trees, which is very harmful to citrus industry. Based on the theory of model averaging, the feasibility of improving the accuracy of quick and non-destructive detection of citrus HLB was studied using the visible and near infrared spectrum technique. The visible and near infrared spectra of citrus leaves were collected and record, and three kinds of leaves with slight HLB, moderate HLB, serious HLB was identied using real time fluorescent quantitative PCR and nutrient deficiency and normal was identified by PCR also, in all five types. Three kinds of different strategies, including the spectra directly stitched, the normalized spectral stitched and model averaging were as basis, combined with partial least squares discriminant analysis (PLS-DA) and multiple linear regression (MLR) method, and the non-destructive detection Spectrometry model of citrus HLB were developed using visible and near infrared spectroscopy respectively. By comparison, it can be found that the detection accuracy of Spectrometry model was higher than visible or near infrared spectroscopy single detection model while the detection accuracy of spectra directly stitched PLS-DA model was highest after derivative preprocessing. The correlation coefficient (R_P) of the model was 0.97, the root mean square error (RMSEP) 0.67, and the total midjudgement rate 3%. The reason was to eliminate baseline drift of spectra. The detection accuracy of spectra directly stitched PLS-DA model after normalized was second, and the total midjudgement rate was 7%. The detection accuracy of visible and near infrared average model was lowest, and the total midjudgement rate was 7.2%. The experimental resultsshowed that using visible and near infrared spectroscopy combined with spectra stitched method can improved the detection accuracy of non-destructive detection model of Citrus HLB, and the research can provide a reference for other areas of the Spectrometry.
		2018 Vol. 38 (02): 528-534 [Abstract] ( 292 ) RICH HTML PDF (5045 KB) ( 259 )

	535	College of Geosciences and Surveying Engineering, China University of Mining and Technology, Beijing 100083, China
		QIAO Xiao-jun, JIANG Jin-bao^*, LI Hui, QI Xiao-tong, YUAN De-shuai
		DOI: 10.3964/j.issn.1000-0593(2018)02-0535-05
		Moldy peanuts are likely to contain a strong carcinogen-aflatoxin. Identifying and separating the moldy peanuts quickly can prevent aflatoxin entering the food chain at the source, and reduce the risk of human ingesting aflatoxin. The study is to determine spectral features or index models to identify moldy peanuts efficiently by spectral analysis in Visible and Near-Infrared (VIR) hyperspectral images. Totally 253 moldy peanuts samples and 247 healthy samples were selected to obtain hyperspectral images, and a mean spectrum was calculated from each peanut kernel to represent the moldy or healthy sample. The continuous continuum removal was carried out on the spectra pixel-by-pixel. The modified first-order differential with different step-length was conducted, and the index of Area_500～650 was calculated among dominantly separable spectral region of 500~650 nm. Then, the continuous Wavelet transform was applied to extract the spectral information of shapes and locations. Also, the index of Index_cwt was proposed to extract mold information. Results showed that the J-M distance was 1.95 in Area_500-650 and 1.99 in Index_cwt, which indicates that the performance of both Area_500～650 and Index_cwt is good enough to separate the moldy peanuts from the healthy.
		2018 Vol. 38 (02): 535-539 [Abstract] ( 379 ) RICH HTML PDF (2686 KB) ( 387 )

	540	Exploration of the Interaction Mechanism between Doxorubicin Hydrochloride and DNA by Spectroscopic Techniques and Isothermal Titration Calorimetry
		WANG Huan, GOU Xing-xing, PU Xiao-hua^*, WANG Jiao, HU Xiao-bing, LI Zong-xiao
		DOI: 10.3964/j.issn.1000-0593(2018)02-0540-06
		The interaction processing of anti-cancer drug doxorubicin hydrochloride (DOX) with DNA was systematically investigated using fluorescence spectroscopy, ultraviolet-visible spectroscopy, infrared spectroscopy，circular dichroism and isothermal titration calorimetry measurements. The binding constant Ka, the binding-site number n, the reaction enthalpy ΔH and the reaction entropy ΔS of the interaction were obtained. In the binding process, the helix of B-DNA can have a certain degree of structural variations. The data of fluorescence spectrum indicated that DNA was a good quencher for the fluorescence of DOX. IR data certified the cation DOX⁺ binding with the phosphate groups of DNA through strong electrostatic attraction, while the C—H bonds of DOX may be associated with the bases of DNA by hydrophobic interaction. The Changes of enthalpy and entropy of the binding process were determined by ITC, which indicated that the process was driven by the hydrophobic interactions between the hydrocarbon chain of DOX and the bases of DNA.
		2018 Vol. 38 (02): 540-545 [Abstract] ( 373 ) RICH HTML PDF (2630 KB) ( 413 )

	546	Effects of Cuprum Stress on Position of Red Edge of Maize Leaf Reflection Hyperspectra and Relations to Chlorophyll Content
		LI Yuan-xi^{1, 3, 5}, CHEN Xi-yun^{1, 2*} ，LUO Da^{1, 4, 5}, LI Bo-ying¹, WANG Shu-ren¹, ZHANG Li-wei¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0546-06
		The effects of Cuprum stress on reflectance spectra and chlorophyll content of maize leaves were studied by corn planting under 5 different Cu²⁺ concentration treatment. During the indoor experiment, hyperspectral reflectance and the corresponding contents of chlorophyll of leaves of maize seedling were measured and their changing trends and relationships between Cu²⁺ concentration, chlorophyll content and red edge position (wavelength of reflection spectra) were analyzed. Results showed that the corn leaf reflection spectra had the obvious “blue shift of red edge” phenomenon, namely the red edge position of leaf spectra moved to short wave. The red edge position significantly correlated to Cuprum concentration (R=0.76), i. e. the blue shift of red edge increased with Cuprum concentration. In the meanwhile red edge blue-shifts increased with the extension of stress time. The chlorophyll a, chlorophyll b content and their ratio (Chla/Chlb) were significantly different between the five stress treatments (p=0.002, 0.007, 0.001). The content of chlorophyll covaried with Chla/Chlb. At the same time, Chla/Chlb and the concentration of Cuprum in the culture solution showed negative and significant correlation (r=-0.898), whilst, Chla/Chlb was significant and positively correlated with the mean red edge position (r=0.814). These results indicated that the blue shift of red edge of the reflectance spectra in the leaves of maize caused by Cuprum stress should attributed to the increase of chlorophyll b relative to chlorophyll a, which changed the leaf absorption spectrum and altered the red edge position of leaf reflectance.
		2018 Vol. 38 (02): 546-551 [Abstract] ( 236 ) RICH HTML PDF (1079 KB) ( 106 )

	552	Pork Freshness Spectral Feature Index: Development and Sensitivity Analysis
		HUANG Chang-ping¹, ZHU Xin-ran^{1, 2}, ZHANG Chen-lu³, QIAO Na^{1, 4}, HU Shun-shi³, ZHANG Li-fu^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0552-07
		While it is easy to rotten resulting from numerous factors including the enzyme reaction and microbial reaction during its storage, transportation and varied fine processes, pork is one of the main meat products daily consumed in China, . Consequently, before brought onto the dinner table, the pork bought from the market may be not fresh, which will not only affect the taste but also human health. Pork freshness is considered as one of the major driving factors for consumers to buy or not. Therefore, it is very important and also urgently needed to detect pork freshness in situ timely, quickly and accurately in order for consumer’s food safety. Compared to traditional physical and chemical testing methods operated in laboratory, the novel visible/near-infrared spectral analysis technology for detection of cold fresh pork quality has attracted wide interest recently, due to -features quickness, high efficiency, non-destruction and non-contact of the visible/near-infrared spectral analysis technology.And hence it is more suitable for food safety quick-detection. However, most of current researches have focused on the spectral model development based on statistical methods, which results in lack of physical meaning and poor applicability, and hence hinders the application and popularization of the spectroscopy technology. The visible/near-infrared spectral features of pork with varied freshness were investigated in this paper. On this basis, a pork freshness spectral feature index (FI) was constructed using the stable absorption property of pork myoglobin at 760 nm. Additionally, the sensitivities of FI to spectral resolution and signal-to-noise (SNR) were analyzed by simulations. Our research indicated that FI was simple but had a clear physical meaning, and can become a good proxy of pork freshness. Furthermore, the FI showed a relative low dependency on the spectrometer’s key properties, such as spectral resolution and SNR. It may work well as long as the spectral resolutions at both 760 nm and adjacent bands are better than 10 nm, and the SNRs are no lower than 45∶1. This study may provide a scientific basis for the design and development of low-cost and handheld portable spectrometers aiming for pork freshness quick detection in consumer markets.
		2018 Vol. 38 (02): 552-558 [Abstract] ( 283 ) RICH HTML PDF (6016 KB) ( 254 )

	559	Classification of Fishness Based on Hyperspectra Imaging Technology
		ZHANG Hai-liang¹, CHU Bing-quan², YE Qing¹, LIU Xue-mei¹, LUO Wei^1*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0559-05
		This study investigated the feasibility of using near infrared hyperspectral imaging system (NIR-HIS) technique for non-destructiveidentification of fresh and frozen-thawed fish fillets. Hyperspectral images of freshness, storage time, and frozen-thawed times offillets for turbot flesh were obtained in the spectral region of 380~1 023 nm. Reflectance values were extracted from each region of interest (ROI) of each sample. Competitive adaptive reweighted sampling (CARS) algorithm, successive projections algorithm (SPA) and genetic algorithm (GA) were carried out to identify the most significant wavelengths. Based on the fifty-seven, thirty-one and sixty-six wavelengths suggested by CARS, SPA and GA, respectively, two classified models (least squares-support vector machine, LS-SVM and SIMCA) were established. Among the established models, SPA-LS-SVM model performed well withthe highest classification rate (100%) in calibration and 98% in prediction sets. SPA-LS-SVM and CARS-LS-SVM models obtainedbetter results 98% and 96% of classification rate in prediction set with thirty-one and fifty-seven effective wavelengths respectively. The CARS-SIMCA, GA-SIMCA and SPA-SIMCA models obtained poor results with 52% of classification rate in prediction set. The results showedthat NIR-HIS technique could be used to identify the varieties of fresh and frozen-thawed fish fillets rapidly and non-destructively, and SPA and CARS were effective wavelengths selection methods.
		2018 Vol. 38 (02): 559-563 [Abstract] ( 238 ) RICH HTML PDF (2585 KB) ( 241 )

	564	A Model on Extracting the Pollution Information of Heavy Metal Copper Ion Based on the Soil Spectra Analyzed by HHT in Time-Frequency
		YANG Ke-ming¹, WANG Guo-ping^1，2, FU Ping-jie¹, ZHANG Wei¹, WANG Xiao-feng¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0564-06
		The amount of information that the different Cu²⁺ contents in soil are mapped to the soil spectra is very weak, and the noises in the hyperspectral data are also very difficult to avoid. Thus the sky point of the research would be how to extract the weak Cu²⁺ information from the complex noise environment of soil spectra. The empirical mode decomposition (EMD) algorithm can effectively remove the noise in hyperspectral data. Further more, the EMD is the premise of Hilbert transform that is a kind of time-frequency analysis on nonlinear and unstable signal. Therefore the time-frequency analysis algorithm on Hilbert-Huang transform (HHT) could be used for de-noise processing and information extracting of the soil spectra after the Huang transform is introduced. In this paper, through the HHT was applied in time-frequency to analyze the soil spectra polluted by different Cu²⁺ concentrations, and the information mining of Cu²⁺ pollution in soil spectra was achieved based on the curves such as envelope, modulation signal and frequency spectrum of each intrinsic mode function (IMF) component that could be decomposed out from the original soil spectra by EMD. The study results showed that, the analyzing results of soil spectra were identical based on the time-frequency HHT when the soil was polluted by same Cu²⁺ concentrations, but non-identical when polluted by different Cu²⁺ concentrations, so that the Cu²⁺ content in soil can be also retrieved based on the IMF components. Accordingly, the HHT analysis in time-frequency provides a new method and idea for information extracting, spectral diagnosing and Cu²⁺ content retrieving of soil spectra.
		2018 Vol. 38 (02): 564-569 [Abstract] ( 224 ) RICH HTML PDF (5935 KB) ( 212 )

	570	A Simple and Efficient Method for CRISPR/Cas9-Induced Rice Mutant Screening
		FENG Xu-ping^{1, 2}, PENG Cheng³, ZHANG Chu^{1, 2}, LIU Xiao-dan^{1, 2}, SHEN Ting-ting^{1, 2}, HE Yong^{1, 2*}, XU Jun-feng³
		DOI: 10.3964/j.issn.1000-0593(2018)02-0570-05
		Mutant screening is an important step for CRISPR/Cas9 gene editing technology employed in crop breeding program. The present study proposes a visual identification method of CRISPR/Cas9-induced rice mutants based on near-infrared hyperspectral image technology. A total of 1 200 samples of rice seeds were collected, comprising 600 wide types and 600 CRISPR/Cas9-induced mutant samples. The whole data set was divided into two groups according to the Kennard-Stone algorithm, a calibration set (400 samples) and a prediction set (200 samples) for each class. 24 optimal wavelengths were selected by 2^nd spectra algorithm after preprocessing the selection spectral region with absolute noises by wavelet transform. Radial basis function neural network (RBFNN), extreme learning machine (ELM) and K-nearest neighbor (KNN) were used to build discrimination models based on the preprocessed full spectra and feature wavelengths. The results demonstrated that neural networks models achieved good recognition ability. The RBFNN model calculated on the optimal wavelength showed classification rates of 92.25% and 89.50% for calibration set and prediction set, respectively. Finally, the classification of mutant seeds could be visualized on prediction maps by predicting the features of each pixel on individual hyperspectral image based on 2^nd derivative-RBFNN model. It was concluded that hyperspectral imaging together with chemometric data analysis was a promising technique to identify CRISPR/Cas9-induced rice mutants, which offered a powerful tool for evaluating large number of samples from CRISPR/Cas9 gene editing performance trials and breeding programs.
		2018 Vol. 38 (02): 570-574 [Abstract] ( 284 ) RICH HTML PDF (2197 KB) ( 274 )

	575	Hyperspectral Remote Sensing Based Modeling of Cu Content in Mining Soil
		TU Yu-long, ZOU Bin^*, JIANG Xiao-lu, TAO Chao, TANG Yu-qi, FENG Hui-hui
		DOI: 10.3964/j.issn.1000-0593(2018)02-0575-07
		To explore the feasibility of evaluating soil Cu content with Hyperspectral Remote Sensing method, 83 soil samples were collection from a certain diggings in Hunan Province. Using ASD field spectrometer and Induced Coupled Plasma Atomic Emission Spectrometry collecting the reflectance spectra and Cu content. The reflectance spectra were processing with several method: resampling, first/second derivative, standard normal variate. Based on the transformational spectra, potential modeling variables were selected by using principal component analysis and correlation analysis. Final model with stepwise regression were established. Important wavelengths were recognized that respond to Cu content based on the optimal model. The result showedthat, compared to traditional principal component analysis method, because of retaining the weak spectrum signal, principal component stepwise regression with standard normal variate spectra can improve the accuracy of Cu content estimation (R²=0.86), and the estimation of predicting samples is effective. The residual error of modeling samples and predicting samples is 0.76 and 1.29, and it passed the F test. In study area, the reflectance on 360~400, 922~1 009, 1 833~1 890 and 2 200~2 500 nm was indicative to Cu content. The study result will enrich a typical case of diggings in South of China, and provide theoretical support for developing method of soil environment monitor based on Hyperspectral Remote Sensing.
		2018 Vol. 38 (02): 575-581 [Abstract] ( 279 ) RICH HTML PDF (6210 KB) ( 263 )

	582	Determination of Rare Earth Elements in Geological Samples by High-Energy Polarized Energy-Dispersive X-Ray Fluorescence Spectrometry
		YUAN Jing, SHEN Jia-lin^*, LIU Jian-kun, ZHENG Rong-hua
		DOI: 10.3964/j.issn.1000-0593(2018)02-0582-08
		Rapid determination of rare earth elements (REEs) in geological samples based on X-ray Fluorescence Spectrometry (XRF) is always a difficulty because of the characteristics of the rare earth elements and the limitations of traditional X-ray fluorescence spectrometer. To sovle this problom, a rapid simultaneous multi-element analysis for La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu and Y in soil, rock and deposit has been established using High-Eenrgy Polarized Energy-Dispersive X-ray Fluorescence Spectrometer (HE-P-EDXRF). The pressed powder pellet technique was adoped because of its simple sample preparation. Fifty-nine reference samples were used for the calibration. The measureing conditions of target elements were discussed, including the selection of analytical line and secondary target, matrix effect and spectral overlapping interence of some elements. The correlation coefficients of the linear regression lines for La, Ce, Pr, Nd and Ywere >0.99, and the rest were >0.969. Detection limits for Pr were 4.09 ppm and 0.03~2.13 ppm for the rest. The rock composition standard material GBW07105 was detected for 10 replicate measurements, and the relative standard deviations(RSD) was 0.81%~8.35%. The average relative error of test set between EDXRF data and ICP-MS data was 4.4%~15.4%. In a word, this method could achieve accurate determination of rare earth elements in rock, soil and deposit rapidly, and it is simple in operation.
		2018 Vol. 38 (02): 582-589 [Abstract] ( 262 ) RICH HTML PDF (2718 KB) ( 481 )

	590	Research of Carborne γ-Ray Energe Spectrum Radiation Dose Rate Based on FFT-BP Network Model
		XU Li-peng^{1, 2}, GE Liang-quan^1*, DENG Xiao-qin², CHEN Li², ZHAO Qiang², LI Bin², WANG Liang²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0590-05
		In order to measure the radiation dose rate accurately with carborne γ spectrometer patrol system, proposed a modified back-propagation network(BP network) model basised on fast fourier transform background deduct method(FFT-BP network model). Using γ-ray energy spectrum analysis method to test the carborne γ-ray energe spectrum of Cs-137 of different spacings, adopting FFT method to deduct the background of spectrum data then get new spectrum data. The modified B-P network model is applied to qualitatively predict the radiation dose rate of unknow dose carborne γ spectrum, by comparing the predicted results with fitting results of 3 function models to verify the effect of FFT-BP network model. The results show the FFT deduct method can weaken the influence of the scattering background on γ spectrum and reduce spectrum background effectively. The correlation coefficients between characteristic peak area and net area getting from new spectrum are 0.99 (p<0.05), which shows a remarkable correlation. In the process of model fitting, FFT-BP network model shows strong ability of learning and generalization, the prediction of experimental results is ideal, relative error and accumulative error are below 0.6% and 9% respectively, it has better effect than mathematical methods and gamma spectra method and it also can reduce the error of radiation dose rate analized by γ-spectra analysis method, improve the work efficiency effectively. There fore, FFT-BP network model can apply to predictive analysis of γ-ray energy spectrum radiation dose, which provide a new and efficient method for carborne γ spectrometer patrol system to measure radiation dose.
		2018 Vol. 38 (02): 590-594 [Abstract] ( 313 ) RICH HTML PDF (2383 KB) ( 171 )

	595	Development of a Compact Synchronizer for Laser-Induced Breakdown Spectroscopy
		LI Qiu-shi, LI Jia-ming, YANG Ping, YANG Xin-yan, HAO Zhong-qi, SHEN Meng, ZHU Yi-ning, GUO Lian-bo, LI Xiang-you^*, ZENG Xiao-yan
		DOI: 10.3964/j.issn.1000-0593(2018)02-0595-05
		The intensities and signal-to-noise ratios(SNRs)of characteristic spectrum are remarkably different under disparate delay times in Laser-Induced Breakdown Spectroscopy(LIBS), which affects the performance of quantitative analysis directly. Conventionally, the general digital delay generator is used to control the delay time in LIBS, butit’s not suitable for compact LIBS equipmentsdue to its large size, high power and high price. In this study, a compact synchronizer (LDG3.0) with 55 ps resolution was designed and built by using a microcontroller unit and simple circuits. The LDG3. 0 had a considerably smaller size, lower power and lower price than a general digital delay generator DG535. Quantitative analysis of V element in iron samples was investigated to compare the performance of LDG3.0 and DG535 in LIBSsystem. The results showed that the two LIBS systems with LDG3.0 and DG535 had almost the same calibration curve of V, and the determination coefficient R² were both above 0.997. The average relative standard deviation(RSD) of V by LIBS system with LDG3.0 was 2.28% which slightly smaller than LIBS system with DG535, and the limit of detection (LoD) of the former was 19.90 μg·g^-1 which sligthly below the latter. Therefore, the self-builtsynchronizer LDG3.0 has approximately the same accuracy with DG535 in LIBS systemand meets the control and integration requirements of LIBS. The LDG3.0 is especially suitable for compact LIBS instruments.
		2018 Vol. 38 (02): 595-599 [Abstract] ( 258 ) RICH HTML PDF (2718 KB) ( 324 )

	600	Feasibility Study of Mars Rover’s Laser Induced Breakdown Spectroscopy Based Mie-Lidar Design
		HONG Guang-lie¹, ZHOU Yan-bo^1，2, LIU Hao¹, KONG Wei¹, SHU Rong^1,2*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0600-06
		It has important significance on the investigation of ground-based detection of mars aerosol for study mars atmospheric environment. To perform aerosol detection based on the constraint of saving mars rover’s or lander’s volume and weight, we investigated the feasibility of designing a Mie-Lidar which compacted with rover based Laser Induced Breakdown Spectroscopy (LIBS). Beam splitter parts and detection module, along with rover based LIBS’s hardware, comprised the LIBS based Mie-Lidar, the LIBS and the Mie-Lidar work independently and they didn’t interfere each other. One day’s primitive data collected by Phoenix mission’s lander was processed, and extinction coefficient profile was derived, with this profile and LIBS’s parameter, signal-to-noise ratio (SNR) of the Lidar calculated. The result showed that LIBS based Lidar reached SNR of 25 dB at 4 km height, i.e., top of martian boundary layer, and downgraded to 0 dB around 10 km altitude. Such outcome proved that letting LIBS based Mie-Lidar working on mars is feasible. It is not only volume and wight saving, but simplifies data recovering processess when we detect mars aerosol with LIBS based Mie-Lidar.
		2018 Vol. 38 (02): 600-605 [Abstract] ( 242 ) RICH HTML PDF (1638 KB) ( 468 )

	606	Experimental Study on Broadband Coherent Anti-Stokes Spectroscopy
		HOU Guo-hui, CHEN Bing-ling, LUO Teng, LIU Jie, LIN Zi-yang, CHEN Dan-ni^, QU Jun-le^
		DOI: 10.3964/j.issn.1000-0593(2018)02-0606-05
		Our imaging system is based on a super-continuum source, which can provide all the samples’ active Raman vibration mode in a range from 0～4 000 cm^-1 at the same time. The coming probe pulse interacts with the sample, forming the broadband coherent anti-Stokes Raman scattering (CARS) signal. Then, the image can be reconstructed according to the different chemical bonds, and the distribution of different chemical bonds in the sample can be obtained. In this paper, 110-nm pure polystyrene beads formed a certain thickness of thin films, which can endure high power, by tuning the detection pulse and super-continuum pulse overlay time, measuring the time distribution of the CARS signal and then using exponential decay curve fitting through a chemical bond signal intensity at 1 000 cm^-1. This is called the dephasing time. Additionally, it was compared with the CARS dephasing time reported in the literature, and it was determined that it belonged to two-colour or three-colour CARS. To inspect the system application in biological imaging, we carried out the in vivo tissue biology application experiment through recorded data reconstructed in the CARS image at 2 940 cm^-1 and the distribution of CH chemical bonds in tissues, and then directly used wavelet transform for image denoising. The denoised image had a clearer outline, and the results showed that the resonant part of the CARS signal contrast was strong and directly using the wavelet transform denoising method can obtain a better image effect. However, the signal-to-noise ratio of the resonant signal was poor, so the use of this approach was not appropriate, and other methods needed to be used to obtain a good signal contrast with the image. Then, according to the interest chemical bond with a good signal contrast to reconstruct image, after the wavelet transform for image denoising, the image will not only become clear and smooth, but have a good vision effect.
		2018 Vol. 38 (02): 606-610 [Abstract] ( 235 ) RICH HTML PDF (3170 KB) ( 183 )

	611	Research on Low Cost Hydrogen Sulfide Sensor Based on Spectral Absorption
		CHEN Shu-wang¹, WANG Zhao-zhao¹, TANG Dong-lin²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0611-05
		Nowadays, the development trend of H₂S concentration detection is real-time detection. The method based on spectral absorption principle is one of the development directions. The broadband light source was used to replace the high cost narrow band light source used in the past, so as to reduce the cost of the whole system and improve the practicability of the detection system. Narrow band light can be obtained by Bragg grating filtering for broad band light source. The light wave obtained by this method must be noise and fluctuate. So it was filtered to eliminate the noise and fluctuation of part of the system, and then the light beam splitter was used to make the difference between the detected optical path and the reference optical path. The differential signal not only eliminated part of the system noise and fluctuation, but also eliminated fundamental wave component. The useful signal value was relatively large, and the signal-to-noise ratio was increased. The second harmonic signal was deduced by mathematical analysis. The second harmonic was observed by SIMILINK simulation. Different concentrations of H₂S gas would have different output signals, and the concentration of gas would be obtained. The advantages of the dual optical path difference method, harmonic detection technique and narrow band filtering technology were that the cost was reduced, the signal-to-noise ratio was increased, and the detection capability of the system was improved. The experimental results showed that it was feasible to detect H₂S gas concentration by using the dual optical path difference method to extract harmonic signal on the basic of LED broad band light source. This method will reduce the system cost and provide the possibility for large-scale practical application.
		2018 Vol. 38 (02): 611-615 [Abstract] ( 201 ) RICH HTML PDF (1552 KB) ( 98 )

	616	Photoacoustic Spectroscopy Based Methane Sensor Using a Double-Pass Photoacoustic Cell
		YANG Yan-fang^{1, 2}, PEI Kai-long^{1, 2}, YIN Xu-kun^{1, 2}, WU Hong-peng^{1, 2}, LI Shang-zhi^{1, 2}, CUI Ru-yue^{1, 2}, MA Wei-guang^{1, 2}, ZHANG Lei^{1, 2}, YIN Wang-bao^{1, 2}, DONG Lei^{1, 2*}, JIA Suo-tang^{1, 2}
		DOI: 10.3964/j.issn.1000-0593(2018)02-0616-05
		A laser based Photoacoustic sensor system was demonstrated and developed for methane (CH₄) detection using a custom double-pass photoacoustic cell with a large inner diameter. The sensor used a butterfly-package distributed feedback (DFB) laser with its wavelength targeting the CH₄ absorption line at 6 046.96 cm^-1. A high-reflection plane mirror was positioned behind the photoacoustic cell to enhance the absorption optical path and improve the detection sensitivity. The sensor parameters including the modulation frequency, modulation depth of the laser and gas flow were optimized. Under theatmospheric pressure, the novel CH₄ sensor showed a detection sensitivity of 0.21 ppm with a 1 s averaging time, which corresponded to a 1σ normalized noise equivalent absorption (NNEA) of 2.1×10^-8 cm^-1·W·Hz^-1/2. The excellent performance of this CH₄ sensor promises broad applicability to industry, mine, medical and environmental monitoring, etc.
		2018 Vol. 38 (02): 616-620 [Abstract] ( 243 ) RICH HTML PDF (2375 KB) ( 122 )

	621	SONG-China Project High Resolution Spectrograph and High Precision Radial Velocity Measurements of Asteroseismology
		YAN Zheng-zhou^1，2，5, DENG Li-cai¹, ZHANG Chun-guang¹, LUO Chang-qing¹, Grundahl F³, HU Zhong-wen⁴, JI Hang-xin⁴, WANG Jia-ning⁴, XU Ming-ming⁴, DAI Song-xing⁴, Andersen M F³, WANG Kun⁵, TIAN Jian-feng¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0621-06
		SONG (Stellar Observations Network Group) is an international collaboration project involving many countries. Chinese stellar physics community is participating the project as a national member, contributing a full set of instruments and a site. The key instrument is a high resolution spectrograph which, when adopting iodine cell for wave length calibration, can deliver radial velocity measurements at an accuracy of 1 m·s^-1. Such a high accuracy together with the long term stability is the keys to the science goals of SONG, one of which is to study the internal structure of stars directly using the technique of Asteroseismology. In this paper, we are going to present the design, parameters and performance of the spectrograph by using spectra taken during the commissioning of the system. As long term thermo-mechanic stability of the system is extremely important for the science goals, we will also describe the laboratory environments to realize such a condition.
		2018 Vol. 38 (02): 621-626 [Abstract] ( 323 ) RICH HTML PDF (4476 KB) ( 226 )

	627	Measurement of the Gas Temperature in Microwave Plasma by Molecular Emission Spectrometry
		DENG Lei, ZHANG Gui-xin^*, LIU Cheng, XIE Hong
		DOI: 10.3964/j.issn.1000-0593(2018)02-0627-07
		In this study, gas temperature measurements of argon, nitrogen, and air microwave plasmas are achieved by the molecular emission spectrometry of the A²Σ⁺→X²Π_r electronic system of OH radical. The gas temperatures at different microwave powers or gas flow rates were explored, and the axial temperature distributions of nitrogen and air microwave plasma plumes were measured. The experimental results showed that temperatures in the core region of microwave plasma were higher than 2000 K at different working conditions, even up to over 6 000 K in air microwave plasma. At the same working condition, the three kinds of microwave plasma gas temperatures meet: T_Ar<T_N₂<T_Air. The gas temperature increased slightly with the increase of microwave power, and decreased slightly with the decrease of gas flow rate overall. The gas temperatures of nitrogen and air microwave plasma plumes reduced quickly along the axial direction. In order to verify the accuracy of molecular emission spectrometry, the thermocouple was used as a comparison to take the temperature of the dielectric barrier discharge argon plasma. Experiments showed that the temperature measurements of molecular emission spectrometry and thermocouple are fairly consistent.
		2018 Vol. 38 (02): 627-633 [Abstract] ( 286 ) RICH HTML PDF (4810 KB) ( 111 )

	634	Studies on Luminescent Properties of TCNE-Phenanthroline Complex
		Lü Yu-guang, SHI Qi, GUO Qiang, SONG Shan-shan, QIN Yu-shan, WANG Bo, YANG Li-bin^*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0634-04
		Based on the development of probes in recent years, the preparation of luminescent materials with better optical properties has become a hotspot of current chemical workers. This work is intended to prepare a new type of luminescent material with better optical performance to meet people’s daily life and medical demands. The complex of tetracynoethylene-1,10-phenanthroline was formed with tetracynoethylene (TCNE) and 1,10-phenanthroline (Phen) under specific conditions and characterized by UV-Vis spectrometry, Fluorescence spectrometry and Raman scattering spectrometry. Then the reaction mechanism was explored preliminarily. The absorption peaks of complex was compared with the absorption peaks of ligands. It showed that the absorption of complexes was due to the absorption of ligand 1,10-phenanthroline, indicating that tetracynoethylene and 1,10-phenanthroline formed stable complexes. At the same time, the fluorescence spectra were analyzed. It was found that the emission peak of the complex was similar to that of the ligand tetracynoethylene, and the fluorescence of the complex was believed to be derived from the π—π^* electron transition of the ligand. It can be seen from the Raman spectra that the Raman intensity of the complex at 1 000~1 600 cm^-1 was significantly enhanced compared with the Raman intensity of tetracynoethylene ligand. The resonant Raman scattering was strongly coupled at 1 000~1 600 cm^-1, and these resonant Raman peaks were strongly enhanced due to the charge transfer between molecules. The results suggested that the ligand tetracynoethylene had coordinated successfully with ligand 1,10-Phenanthroline and the fluorescence intensity was significantly improved. At the same time, the absorption of complex mainly came from the ligands absorption. In the above study, the 1,10-Phenanthroline-tetracyanoethylene charge transfer complex was synthesized for the first time and its optical properties were studied. This study provided an experimental basis for the design and synthesis of complexes with superior luminescent properties, promoting the progress of the career of the optics and contributed the exploration and development of new nucleic acid probes.
		2018 Vol. 38 (02): 634-637 [Abstract] ( 185 ) RICH HTML PDF (1290 KB) ( 79 )

	638	Research on the Influence of Spectral Response on Radiation Spectroscopy Thermometry
		YANG Bin¹, GUO Hao-ran¹, CHEN Xiao-long², PAN Ke-wei², GUI Xin-yang¹, CAI Xiao-shu¹, LIU Pei-jin³
		DOI: 10.3964/j.issn.1000-0593(2018)02-0638-05
		In order to comprehend the influence of spectral response coefficients on radiation spectroscopy thermometry, the VIS (visible, 200～1 100 nm) and NIR (near-infrared, 900～1 700 nm) spectrometers were used to measure the blackbody radiation spectrums at different temperature. The spectral characteristics of high temperature blackbody radiation spectrums in different wavebands were analyzed. The appropriate response wavebands of different spectrometers were selected to measure temperature. The changes of spectral response coefficient with temperature in this optimized waveband were obtained. The influence of temperature on response coefficient was analyzed in detail. The wavelength range of temperature fitting of radiation spectroscopy and the selecting criterions of response coefficient were summarized. And the influence of selecting of wavelength and response coefficient on thermometry were analyzed. It provides the important references for improving on measurement accuracy of radiation spectroscopy thermometry.
		2018 Vol. 38 (02): 638-642 [Abstract] ( 258 ) RICH HTML PDF (2152 KB) ( 114 )

	643	Terahertz-Statistics-Dependent Approach for Monitoring PM_2.5 in Air
		JIANG Chen¹, ZHAN Hong-lei^1, LI Qian¹, ZHAO Kun^1, ZHANG Zhen-wei², ZHANG Cun-lin²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0643-07
		The study presented a quantitative investigation in monitoring the fine particulate matter with the aerodynamic diameters less than 2.5 μm (PM_2.5) in air with terahertz (THz) technique. Absorption bands were observed and linear relations were obtained between PM_2.5 mass and absorbance at selected frequencies with correlation coefficients R of ~0.86. The utilization of principal component analysis (PCA) proved the similar absorption trend in the entire range with increasing PM_2.5 mass. In order to improve the prediction precision, we employed other three statistical methods including partial least square (PLS), support vector machine (SVM) and back propagation artificial neural network (BPANN) for the quantification of PM_2.5. Compared with single linear models, statistical models had larger prediction correlation and smaller errors. For BPANN model, R and root-mean square error (RMSE) achieved 0.999 as well as 0.016 mg in training and 0.912 as well as 0.207 mg. Therefore, the combination of THz technique and statistical methods represents high precision of prediction and really can act as an effective tool to monitor PM_2.5 together with other normal approaches.
		2018 Vol. 38 (02): 643-649 [Abstract] ( 192 ) RICH HTML PDF (2499 KB) ( 87 )

	650	Contrast Analysis of ¹³C Nuclear Magnetic Resonance and Infrared Spectroscopy of Particulate Organic Carbons in Different Fertilizations
		QU Xiao-jing^1,2, WU Jing-gui^1*, LI Ming-ming³, ZHANG Le-le², CAO Li-jia²
		DOI: 10.3964/j.issn.1000-0593(2018)02-0650-04
		This paper comparatively studied the structural differences of particulate organic carbon (POC) in different organic fertilizations, to clear the mechanism of action of POC in soil carbon sequestration. Compared with chemical fertilization as the control, four kinds of organic material for this positioning fertilizer experiment were chosen, and the effects we analyzed of different organic fertilization on the structure of POC through the ¹³C Nuclear Magnetic Resonance (NMR) and Infrared Spectroscopy (IR). The results showed that POC was mainly composed of oxygen-containing groups and aliphatic structures, in which aliphaticity is higher than 75% and the content of oxygen-containing groups are higher than 50%; Different organic fertilization had greater difference impact on POC’s structure, and leaves fertilization could be improve POC aromaticity. At the same time, hydrophilic also increased significantly, about 0.78% than the control; Cow dung, maize straw or leaves could increase the aromaticity of POC in the short-term, the cow dung or straw treatment was more favorable for the stability of POC. Especially the straw treatment which aromaticity was higher 0.35% and 0.11% than control and cow dung, and the hydrophilicity was far lower than the two. The results of Infrared spectrum and nuclear magnetic analysis were basically identical, infrared spectrum can be used for preliminary screening for a large number of POC samples.
		2018 Vol. 38 (02): 650-653 [Abstract] ( 248 ) RICH HTML PDF (677 KB) ( 81 )

	654	Interaction between Fleroxacin and Lysozyme by Using Multi-Spectral Techniques and Molecular Docking
		FANG Qing¹, WANG Yi-run¹, GUO Chen-hui¹, LIU Ying^1,2*
		DOI: 10.3964/j.issn.1000-0593(2018)02-0654-06
		The interaction of fleroxacin (FLE) with extracelluar protein (lysozyme, LYSO) was investigated by using multi-spectral techniques and molecular docking in vitro. Fluorescence spectra studies indicated that FLE quenched LYSO fluorescence in a static mode with binding constants (K_a) of 4.10×10⁴ and 0.74×10⁴ L·mol^-1 at 298 and 310 K, respectively. The thermodynamic parameters demonstrated that hydrogen bonds and van der Waals forces played the major role in the binding process. Based on the Frster theory of nonradiative energy transfer, the binding distance (r) between FLE and the inner tryptophan residues of LYSO was calculated to be 3.16 nm. The Hill’s coefficient (n_H) was calculated by using involved equations, implying the negative cooperativity between them. Circular dichroism spectra (CD) indicated the secondary structure of LYSO was partially destroyed by FLE with the α-helix percentage decreasing from 21.1% to 8.8%. UV-Vis spectral, synchronous fluorescence and three-dimensional fluorescence spectra revealed the binding interaction could cause conformational and micro-environmental changes of LYSO. The results of molecular docking showed that FLE was mainly bound in the active site hinge region where ASP-52, TRP-62 and TRP-63 were located, and well supported the thermodynamic results. Besides, FIE made the activity of lysozyme decrease with the increasing concentration of fleroxacin, indicating that structural changes in lysozyme can cause the inhibition of lysozyme activity. The work clarified the interaction mechanism of FLE with LYSO at molecular level.
		2018 Vol. 38 (02): 654-659 [Abstract] ( 183 ) RICH HTML PDF (2562 KB) ( 90 )

	660	Stellar Spectra Classification with Entropy-Based Learning Machine
		LIU Zhong-bao¹, REN Juan-juan², SONG Wen-ai^1*, ZHANG Jing¹, KONG Xiao², FU Li-zhen¹
		DOI: 10.3964/j.issn.1000-0593(2018)02-0660-05
		Data mining are widely used in the stellar spectra classification. In order to improve the efficiencies of traditional spectra classification methods, Entropy-based Learning Machine (ELM) was proposed in this paper. The entropy was used to describe the uncertainty of classification in ELM. In order to obtain the desired classification efficiencies, the classification uncertainty should be minimized, based on which, we can obtain the optimization problem of ELM. It can be verified that ELM performs well in the binary classification and in the rare spectra mining. Several comparative experiments on the 4 subclasses of K-type spectra, 3 subclasses of F-type spectra and 3 subclasses of G-type spectra from Sloan Digital Sky Survey (SDSS) verified that ELM performs better than kNN (k Nearest Neighbor) and SVM (Support Vector Machine) in dealing with the problem of stellar spectra classification on the SDSS datasets.
		2018 Vol. 38 (02): 660-664 [Abstract] ( 246 ) RICH HTML PDF (410 KB) ( 95 )

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