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Near Infrared Spectroscopy (NIRS) Model-Based Prediction for Protein Content in Cowpea
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作者 Kavera Biradar Waltram Ravelombola +1 位作者 Aurora Manley Caroline Ruhl 《American Journal of Plant Sciences》 CAS 2024年第3期145-160,共16页
Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models... Cowpea (Vigna unguiculata L. Walp) is a multi-purpose legume with high quality protein for human consumption and livestock. The objective of this work was to develop near-infrared spectroscopy (NIRS) prediction models to estimate protein content in cowpea. A total of 116 cowpea breeding lines with a wide range of protein contents (19.28 % to 32.04%) were selected to build the model using whole seed and ground seed samples. Partial least-squares discriminant analysis (PLS-DA) regression technique with different pre-treatments (derivatives, standard normal variate, and multiplicative scatter correction) were carried out to develop the protein prediction model. Results showed: 1) spectral plots of both the whole seed and ground seed showed higher spectral scatter at higher wavelengths (>1450 nm), 2) data pre-processing affects prediction accuracy for bot whole seed and ground seed samples, 3) prediction using ground seed samples (0.64 R<sup>2</sup> 0.85) is better than the whole seed (0.33 R<sup>2</sup> 0.78), and 4) the data pre-processing second derivative with standard normal variate has the best prediction (R<sup>2</sup>_whole seed = 0.78, R<sup>2</sup>_ground seed = 0.85). The results will be of interest in cowpea breeding programs aimed at improving total seed protein content. 展开更多
关键词 COWPEA GERMPLASM PROTEIN Near-infrared Spectroscopy (nirS) Partial Least Squares (PLS)
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Construction of universal quantitative models for the determination of cefoperazone sodium/sulbactam sodium for injection from different manufacturers using near-infrared reflectance spectroscopy 被引量:4
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作者 逄焕欢 冯艳春 +1 位作者 张学博 胡昌勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第1期22-29,共8页
To develop near-infrared (NIR) reflectance spectroscopic methods for the quantitative analysis of cefoperazone sodium/ sulbactam sodium from different manufacturers for injection powder medicaments. Various powders ... To develop near-infrared (NIR) reflectance spectroscopic methods for the quantitative analysis of cefoperazone sodium/ sulbactam sodium from different manufacturers for injection powder medicaments. Various powders of cefoperazone sodium/ sulbactam sodium were directly analyzed by non-destructive NIR reflectance spectroscopy using the spectrometer EQUINOX55. Two quantitative methods via integrating sphere (IS) and fiberoptic probe (FOP) models were explored from 6 batches of commercial samples and 42 batches of laboratory samples at a content ranging from 30% to 70% for cefoperazone and 60% to 20% for sulbactam. The root mean square errors of cross validation (RMSECV) and the root mean square errors of prediction (RMSEP) of IS were 1.79% and 2.85%, respectively, for cefoperazone sodium, and were 1.86% and 3.08%, respectively, for sulbactam sodium; and those of FOP were 2.93% and 2.92%, respectively, for cefoperazone sodium, and were 2.23% and 3.01%, respectively, for sulbactam sodium. Based on the ICH guidelines and Ref. 12, the quantitative models were then evaluated in terms of specificity, linearity, accuracy, precision, robustness and model transferability. The non-destructive quantitative NIR methods used in this study are applicable for rapid analysis of injectable powdered drugs from different manufacturers. 展开更多
关键词 nir diffuse reflectance spectroscopy Non-destructive determination Cefoperazone sodium/sulbactam sodium Injection powder medicament Validation Counterfeit medicine
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RAPID DETERMINATION OF PROTEIN IN MILLET BY FOURIER TRANSFORM NEAR-INFRARED(FTNIR)DIFFUSE REFLECTANCE SPECTROSCOPY
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作者 Le Ming SHI Zhi Hong XU Zhong Xiao PAN Zhi Liang LI Laboratory of Computer Chemistry,Institute of Chemical Metallurgy,Chinese Academy of Sciences,Beijing 100080 Yan Lu YAN Mao JIN Central Laboratory,Beijing Agricultural University,Beijing 100094 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期247-250,共4页
In this paper,the Fourier transform near-infrared(FTNIR)diffuse reflectance spectroscopy is applied for the rapid determination of protein in millet.The partial least-squares(PLS)regression is successfully used as an ... In this paper,the Fourier transform near-infrared(FTNIR)diffuse reflectance spectroscopy is applied for the rapid determination of protein in millet.The partial least-squares(PLS)regression is successfully used as an effective multivariate calibration technique.The calibration set is composed of 20 standard millet samples that the protein contents were determined by the traditional Kjeldahl method.The optimal model dimension is found to be 5 by cross-validation.22 millet samples were determined by the proposed FTNIR-PLS method.The correlation coefficient between the concentration values obtained by the FTNIR-PLS method and the traditional Kjeldahl method is 0.9805.The standard error of prediction(SEP)is 0.28% and the mean recovery is 100.2%.The proposed method has been successfully applied for the routine analysis of protein in about 10,000 grain samples. 展开更多
关键词 PLS nir FTnir)DIFFUSE reflectance SPECTROSCOPY RAPID DETERMINATION OF PROTEIN IN MILLET BY FOURIER TRANSFORM NEAR-infrared
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Noninvasive Detection of Cerebral Blood Flow and Blood Oxygen Based on Inductive Sensing Technology and Near Infrared Spectroscopy
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作者 Cheng Zhou Zexiang Lyu +6 位作者 Maoting Zhang Xin Zou Liang Wei Feng Wang Mingxin Qin Jia Xu Jian Sun 《Journal of Beijing Institute of Technology》 EI CAS 2024年第3期204-212,共9页
The synchronous monitoring of cerebral blood flow and blood oxygen levels plays a pivotal role in the prevention,diagnosis,and treatment of cerebrovascular diseases.This study introduces a novel noninvasive device uti... The synchronous monitoring of cerebral blood flow and blood oxygen levels plays a pivotal role in the prevention,diagnosis,and treatment of cerebrovascular diseases.This study introduces a novel noninvasive device utilizing inductive sensing and near-infrared spectroscopy technology to facilitate simultaneous monitoring of cerebral blood flow and blood oxygen levels.The device consists of modules for cerebral blood flow monitoring,cerebral blood oxygen monitoring,control,communication,and a host machine.Through experiments conducted on healthy subjects,it was confirmed that the device can effectively achieve synchronous monitoring and recording of cerebral blood flow and blood oxygen signals.The results demonstrate the device’s capability to accurately measure these signals simultaneously.This technology enables dynamic monitoring of cerebral blood flow and blood oxygen signals with potential clinical applications in preventing,diagnosing,treating cerebrovascular diseases while reducing their associated harm. 展开更多
关键词 cerebrovascular disease synchronous monitoring inductive sensing near infrared spec-troscopy(nirS)
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The Study of Using Near-infrared Diffuse Reflectance Spectroscopy Rapid Identify Wheat Drought Resistance-Ⅱ 被引量:2
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作者 吴少辉 冯伟森 +5 位作者 谷运红 焦珍 张学品 杨洪强 王卫东 张灿军 《Agricultural Science & Technology》 CAS 2013年第10期1507-1512,共6页
[Objective] The aim was to build an evaluation method rapidly identifying wheat drought tolerance with near infrared diffuse reflectance spectroscopy. [Method] In the research, 36 wheat varieties in 2007-2009 were cho... [Objective] The aim was to build an evaluation method rapidly identifying wheat drought tolerance with near infrared diffuse reflectance spectroscopy. [Method] In the research, 36 wheat varieties in 2007-2009 were chosen and drought-tolerance degrees of wheat were graded and identified according to Winter-wheat Drought Tol- erance Evaluation Technical Standards (GB/T 21127-2007), and harvest wheat grains underwent spectrum collection, with a full-spectrum analyzer, to establish a database. [Result] Based on qualitative analysis and full-spectrum correlation research, the coef- ficient of determination (RSQ) and cross-validation coefficient of determination (1-VR) were concluded at 0.697 5 and 0.600 2, showing near-infrared diffuse reflectance spectroscopy is of significant differences among wheat varieties and of significant or extremely significant correlation with drought-tolerance indices. [Conclusion] The re- search indicates that to evaluate drought-tolerance of wheat with near-infrared diffuse reflectance spectroscopy is a rapid and feasible way, which is simple, convenient without damages on grains, and of practical values for construction wheat drought-tol- erance evaluation index system and identification of breeding materials. 展开更多
关键词 Near infrared diffuse reflectance spectroscopy of wheat drought resis- tance screening index
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Discrimination of Transgenic Rice Based on Near Infrared Reflectance Spectroscopy and Partial Least Squares Regression Discriminant Analysis 被引量:7
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作者 ZHANG Long WANG Shan-shan +2 位作者 DING Yan-fei PAN Jia-rong ZHU Cheng 《Rice science》 SCIE CSCD 2015年第5期245-249,共5页
Near infrared reflectance spectroscopy (NIRS), a non-destructive measurement technique, was combined with partial least squares regression discrimiant analysis (PLS-DA) to discriminate the transgenic (TCTP and mi... Near infrared reflectance spectroscopy (NIRS), a non-destructive measurement technique, was combined with partial least squares regression discrimiant analysis (PLS-DA) to discriminate the transgenic (TCTP and mi166) and wild type (Zhonghua 11) rice. Furthermore, rice lines transformed with protein gene (OsTCTP) and regulation gene (Osmi166) were also discriminated by the NIRS method. The performances of PLS-DA in spectral ranges of 4 000-8 000 cm-1 and 4 000-10 000 cm-1 were compared to obtain the optimal spectral range. As a result, the transgenic and wild type rice were distinguished from each other in the range of 4 000-10 000 cm-1, and the correct classification rate was 100.0% in the validation test. The transgenic rice TCTP and mi166 were also distinguished from each other in the range of 4 000-10 000 cm-1, and the correct classification rate was also 100.0%. In conclusion, NIRS combined with PLS-DA can be used for the discrimination of transgenic rice. 展开更多
关键词 near infrared reflectance spectroscopy genetically-modified food regulation gene protein gene partial least squares regression discrimiant analysis
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Supercritical water syntheses of transition metal-doped CeO_2 nano-catalysts for selective catalytic reduction of NO by CO:An in situ diffuse reflectance Fourier transform infrared spectroscopy study 被引量:12
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作者 Xiaoxia Dai Weiyu Jiang +4 位作者 Wanglong Wang Xiaole Weng Yuan Shang Yehui Xue Zhongbiao Wu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第4期728-735,共8页
In the present study,we synthesized CeO2 catalysts doped with various transition metals(M=Co,Fe,or Cu)using a supercritical water hydrothermal route,which led to the incorporation of the metal ions in the CeO2 lattice... In the present study,we synthesized CeO2 catalysts doped with various transition metals(M=Co,Fe,or Cu)using a supercritical water hydrothermal route,which led to the incorporation of the metal ions in the CeO2 lattice,forming solid solutions.The catalysts were then used for the selective catalytic reduction(SCR)of NO by CO.The Cu‐doped catalyst exhibited the highest SCR activity;it had a T50(i.e.,50%NO conversion)of only 83°C and a T90(i.e.,90%NO conversion)of 126°C.Such an activity was also higher than in many state‐of‐the‐art catalysts.In situ diffuse reflectance Fourier transform infrared spectroscopy suggested that the MOx‐CeO2 catalysts(M=Co and Fe)mainly followed an Eley‐Rideal reaction mechanism for CO‐SCR.In contrast,a Langmuir‐Hinshelwood SCR reaction mechanism occurred in CuO‐CeO2 owing to the presence of Cu+species,which ensured effective adsorption of CO.This explains why CuO‐CeO2 exhibited the highest activity with regard to the SCR of NO by CO. 展开更多
关键词 Supercritical water Nitrogen oxides CO Selective catalytic reduction Diffuse reflectance Fourier transform infrared spectroscopy CEO2
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Determination of Protein and Starch Content in Whole Maize Kernel by Near Infrared Reflectance Spectroscopy 被引量:2
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作者 WEILiang-ming YANYan-lu DAIJing-rui 《Agricultural Sciences in China》 CAS CSCD 2004年第7期490-495,共6页
Using 128 bulk-kernel samples of inbred lines and hybrids, a study was conducted toinvestigate the feasibility and method of measuring protein and starch contents inintact seeds of maize by near infrared reflectance s... Using 128 bulk-kernel samples of inbred lines and hybrids, a study was conducted toinvestigate the feasibility and method of measuring protein and starch contents inintact seeds of maize by near infrared reflectance spectroscopy (NIRS). The chemometricalgorithms of partial least square (PLS) regression was used. The results indicated thatthe calibration models developed by the spectral data pretreatment of firstderivative+multivariate scattering correction within the spectral region of 10000-4000cm-1, and first derivative + straight line subtraction in 9000-4000cm-1 were thebest for protein and starch, respectively. All these models yielded coefficients ofdetermination of calibration (R2cal) above 0.97, while R2cv and R2val of cross and externalvalidation ranged from 0.92 to 0.95, respectively; however, the root of mean squareerrors of calibration, cross and external validation (RMSEE, RMSECV and RMSEP) werebelow 1(ranged 0.3-0.7),respectively. This study demonstrated that it is feasible touse NIRS as a rapid, accurate, and none-destructive technique to predict protein andstarch contents of whole kernel in the maize quality improvement program. 展开更多
关键词 MAIZE Near infrared reflectance spectroscopy (nirS) Protein and starch CALIBRATION model
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Application of Near Infrared Diffuse Reflectance Spectroscopy with Radial Basis Function Neural Network to Determination of Rifampincin Isoniazid and Pyrazinamide Tablets 被引量:3
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作者 DU Lin-na WU Li-hang +5 位作者 LU Jia-hui GUO Wei-liang MENG Qing-fan JIANG Chao-jun SHEN Si-le TENG Li-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第5期518-523,共6页
Partial least squares(PLS),back-propagation neural network(BPNN)and radial basis function neural network(RBFNN)were respectively used for estalishing quantative analysis models with near infrared(NIR)diffuse r... Partial least squares(PLS),back-propagation neural network(BPNN)and radial basis function neural network(RBFNN)were respectively used for estalishing quantative analysis models with near infrared(NIR)diffuse reflectance spectra for determining the contents of rifampincin(RMP),isoniazid(INH)and pyrazinamide(PZA)in rifampicin isoniazid and pyrazinamide tablets.Savitzky-Golay smoothing,first derivative,second derivative,fast Fourier transform(FFT)and standard normal variate(SNV)transformation methods were applied to pretreating raw NIR diffuse reflectance spectra.The raw and pretreated spectra were divided into several regions,depending on the average spectrum and RSD spectrum.Principal component analysis(PCA)method was used for analyzing the raw and pretreated spectra in different regions in order to reduce the dimensions of input data.The optimum spectral regions and the models' parameters were chosen by comparing the root mean square error of cross-validation(RMSECV)values which were obtained by leave-one-out cross-validation method.The RMSECV values of the RBFNN models for determining the contents of RMP,INH and PZA were 0.00288,0.00226 and 0.00341,respectively.Using these models for predicting the contents of INH,RMP and PZA in prediction set,the RMSEP values were 0.00266,0.00227 and 0.00411,respectively.These results are better than those obtained from PLS models and BPNN models.With additional advantages of fast calculation speed and less dependence on the initial conditions,RBFNN is a suitable tool to model complex systems. 展开更多
关键词 Rifampicin isoniazid and pyrazinamide tablets nir diffuse reflectance spectroscopy Partial least square Back-propagation neural network Radial basis function neural network
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Geographic Classification of Chinese Grape Wines by Near-Infrared Reflectance Spectroscopy 被引量:1
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作者 赵芳 赵育 +1 位作者 毛文华 战吉宬 《Journal of Donghua University(English Edition)》 EI CAS 2012年第1期40-45,共6页
Near-infrared reflectance spectroscopy (NIRS) was applied to classify grape wines of different geographical origins (Changli, Huailai, and Yantai, China). Near infrared (NIR) spectra were collected in transmission mod... Near-infrared reflectance spectroscopy (NIRS) was applied to classify grape wines of different geographical origins (Changli, Huailai, and Yantai, China). Near infrared (NIR) spectra were collected in transmission mode in the wavelength range of 800-2500 nm. Wines (n=90) were randomly split into two sets, calibration set (n=54) and validation set (n=36). Discriminant analysis models were developed using BP neural network and discriminant partial least-squares discriminant analysis (PLS-DA). The prediction performance of calibration models in different wavelength range was also investigated. BP neural network models and PLS-DA models correctly classified 100% of the wines in calibration set. When used to predict wines in validation set, BP neural network models correctly classified 100%, 81.8%, and 90.9% of the wines from Changli, Huailai, and Yantai respectively, and PLS-DA models correctly classified 100% of all samples. The results demonstrated that NIRS could be used to discriminate Chinese grape wines as a rapid and reliable method. 展开更多
关键词 near-infrared reflectance spectroscopy (nirS) Chinese grape wines discriminant analysis models BP neural network PLS-DA
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Rapid, Non-Destructive, Textile Classification Using SIMCA on Diffuse Near-Infrared Reflectance Spectra 被引量:2
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作者 Christopher B. Davis Kenneth W. Busch +2 位作者 Dennis H. Rabbe Marianna A. Busch Judith R. Lusk 《Journal of Modern Physics》 2015年第6期711-718,共8页
Soft independent modeling of class analogy (SIMCA) was successful in classifying a large library of 758 commercially available, non-blended samples of acetate, cotton, polyester, rayon, silk and wool 89% - 98% of the ... Soft independent modeling of class analogy (SIMCA) was successful in classifying a large library of 758 commercially available, non-blended samples of acetate, cotton, polyester, rayon, silk and wool 89% - 98% of the time at the 95% confidence level (p = 0.05 significance level). In the present study, cotton and silk had a 62% and 24% chance, respectively, of being classified with their own group and also with rayon. SIMCA correctly identified a counterfeit “silk” sample as polyester. When coupled with diffuse NIR reflectance spectroscopy and a large sample library, SIMCA shows considerable promise as a quick, non-destructive, multivariate method for fiber identification. A major advantage is simplicity. No sample pretreatment of any kind was required, and no adjust-ments were made for fiber origin, manufacturing process residues, topical finishes, weave pattern, or dye content. Increasing the sample library should make the models more robust and improve identification rates over those reported in this paper. 展开更多
关键词 DIFFUSE NEAR-infrared (nir) reflectance Spectroscopy CHEMOMETRICS Soft Independent Modeling of Class ANALOGY (SIMCA) Pattern Recognition TEXTILE Identification Multivariate Analysis
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Quantitative Analysis of Berberine in Processed Coptis by Near-Infrared Diffuse Reflectance Spectroscopy 被引量:4
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作者 ZHANG Yong XIE Yun-fei +3 位作者 SONG Feng-rui LIU Zhi-qiang CONG Qian ZHAO Bing 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2008年第6期717-721,共5页
The near-infrared(NIR) diffuse reflectance spectroscopy was used to study the content of Berberine in the processed Coptis. The allocated proportions of Coptis to ginger, yellow liquor or Evodia rutaecarpa changed a... The near-infrared(NIR) diffuse reflectance spectroscopy was used to study the content of Berberine in the processed Coptis. The allocated proportions of Coptis to ginger, yellow liquor or Evodia rutaecarpa changed according to the results of orthogonal design as well as the temperature. For as withdrawing the full and effective information from the spectral data as possible, the spectral data was preprocessed through first derivative and multiplicative scatter correetion(MSC) according to the optimization results of different preprocessing methods. Firstly, the model was established by partial least squares(PLS); the coefficient of determination(R2) of the prediction was 0.839, the root mean squared error of prediction(RMSEP) was 0.1422, and the mean relative error(RME) was 0.0276. Secondly, for reducing the dimension and removing noise, the spectral variables were highly effectively compressed via the wavelet transformation(WT) technology and the Haar wavelet was selected to decompose the spectral signals. After the wavelet coefficients from WT were input into the artificial neural network(ANN) instead of the spectra signal, the quantitative analysis model of Berberine in processed Coptis was established. The R^2 of the model was 0.9153, the RMSEP was 0.0444, and the RME was 0.0091. The values of appraisal index, namely R^2, RMSECV, and RME, indicate that the generalization ability and prediction precision of ANN are superior to those of PLS. The overall results show that NIR spectroscopy combined with ANN can be efficiently utilized for the rapid and accurate analysis of routine chemical compositions in Coptis. Accordingly, the result can provide technical support for the further analysis of Berberine and other components in processed Coptis. Simultaneously, the research can also offer the foundation of quantitative analysis of other NIR application. 展开更多
关键词 Near-infrared(nir spectroscopy Partial least squares Artificial neural network Wavelet transformation BERBERINE
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Use of near-infrared reflectance spectroscopy for the rapid determination of the digestible energy and metabolizable energy content of corn fed to growing pigs 被引量:4
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作者 Juntao Li Quanfeng Li +4 位作者 Defa Li Yiqiang Chen Xiaoxiao Wang Wenjun Yang Liying Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2017年第1期161-169,共9页
Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and sevente... Background: The ability of near-infrared reflectance spectroscopy(NIRS) to determine the digestible energy(DE)and metabolizable energy(ME) content of corn fed to growing pigs was tested. One hundred and seventeen corn samples, comprising different planting regions and varieties were collected from all over China in a three-year period. The samples were randomly split into a calibration set(n = 88) and a validation set(n = 29). The actual and calculated DE and ME content of the corn samples was determined by digestion-metabolism experiments and the prediction equations of Noblet and Perez(J Anim Sci. 71:3389–98,1993). The samples were then subjected to NIRS scanning and calibrations were performed by the modified partial least square(MPLS) regression method based on77 different spectral pre-treatments. The NIRS equations based on the actually determined and calculated DE and ME were built separately and then validated using validation samples.Results: The NIRS equations obtained from actually determined DE, the coefficient of determination for calibration(RSQcal), cross-validation(R^2CV), and validation(RSQv) were 0.89, 0.87 and 0.86, and these values for determined ME were 0.87, 0.86 and 0.86. For the NIRS equations built from calculated DE, the RSQcal, R^2CV, and RSQvvalues were 0.88, 0.85 and 0.84, and these values for calculated ME were 0.86, 0.84 and 0.82. Except for the equation based on calculated ME(RPD_v= 2.38, 〈 2.50), the other three equations built from actually determined energy and calculated DE produced good prediction performance(RPD_vranging from 2.53 to 2.69, 〉 2.50) when applied to validation samples.Conclusion: These results indicate that NIRS can be used as a quantitative method for the rapid determination of the available energy in corn fed to growing pigs, and the NIRS equations based on the actually determined energy produced better predictive performance than those built from calculated energy values. 展开更多
关键词 Corn Digestible energy Growing pigs Metabolizable energy Near-infrared reflectance spectroscopy
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Characterization of 4H-SiC substrates and epilayers by Fourier transform infrared reflectance spectroscopy
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作者 董林 孙国胜 +7 位作者 郑柳 刘兴昉 张峰 闫果果 赵万顺 王雷 李锡光 王占国 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第4期548-554,共7页
The infrared reflectance spectra of both 4H SiC substrates and epilayers are measured in a wave number range from 400 cm 1 to 4000 cm-1 using a Fourier-transform spectrometer. The thicknesses of the 4H-SiC epilayers a... The infrared reflectance spectra of both 4H SiC substrates and epilayers are measured in a wave number range from 400 cm 1 to 4000 cm-1 using a Fourier-transform spectrometer. The thicknesses of the 4H-SiC epilayers and the electrical properties, including the free-carrier concentrations and the mobilities of both the 4H SiC substrates and the epilayers, are characterized through full line-shape fitting analyses. The correlations of the theoretical spectral profiles with the 4H-SiC electrical properties in the 30 cm-1-4000 cm 1 and 400 cm-1-4000 cm-1 spectral regions are established by introducing a parameter defined as error quadratic sum. It is indicated that their correlations become stronger at a higher carrier concentration and in a wider spectral region (30 cm-1-4000 cm-1). These results suggest that the infrared reflectance technique can be used to accurately determine the thicknesses of the epilayers and the carrier concentrations, and the mobilities of both lightly and heavily doped 4H-SiC wafers. 展开更多
关键词 4H SiC infrared reflectance epilayer thickness electrical properties
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Far-Infrared Reflectance of the Sintered Samples of Y-Ba-Cu-0 at DifiFerent Quenching Temperature
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作者 ZENG Wensheng ZHANG Guizhong +4 位作者 LI Zengfa ZHANG Guangyin YANG Xiaoming YAN Jie SONG Deying 《Chinese Physics Letters》 SCIE CAS CSCD 1991年第1期36-39,共4页
The sintered samples of Y-Ba-Cu-0 were quenched in air at different temperatures from 950 to 300℃ and their room-temperature far-infrared reflectance spectra were obtained.The spectra were studied by using the Drudc ... The sintered samples of Y-Ba-Cu-0 were quenched in air at different temperatures from 950 to 300℃ and their room-temperature far-infrared reflectance spectra were obtained.The spectra were studied by using the Drudc model and Lorcntzian phonon.From the curve of carrier density vs quench temperature,an orthorhombic-tetragonal phase change is indicated.The phonon oscillation strength changes were explained by the abnormal sensibility in the reflectance spectra. 展开更多
关键词 STRENGTH reflectance infrared
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Application of Short-wave Near-infrared Reflectance Spectroscopy in Controlling Extract of Fructus Cnidii Using Supercritical Carbon Dioxide 被引量:1
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作者 MI Hong GUO Ye +4 位作者 LI Wen-liang Qu Nan DOU Ying REN Yu-qiu REN Yu-lin 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第1期116-119,共4页
Fructus cnidii (Chinese name shechuangzi) is the fruit produced by Cnidium monnieri (L.) Cusson (Umbelliferae). It is a perennial herb that is used to treat skin-related diseases and gynecopathyell. Recent pharm... Fructus cnidii (Chinese name shechuangzi) is the fruit produced by Cnidium monnieri (L.) Cusson (Umbelliferae). It is a perennial herb that is used to treat skin-related diseases and gynecopathyell. Recent pharmacological studies have revealed crude extracts or components isolated from fructus cnidii possess antiallergic, antipruritic, antidermatophytic, antibacterial, antifungal, and antiosteoporotic activities. Osthole and imperatorin are the major compounds present in shechuangzi. They are often used as standards for the evaluation of the quality of shechuangzi products. 展开更多
关键词 Fructus cnidii Supercfitical carbon dioxide Short-wave near-infrared diffuse reflectance spectrum Artificial neural network Degree of approximation
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Influence of the Mode of Wavelength on the Infrared Reflectance and Transmittance in the Fabric
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作者 徐卫林 姚穆 《Journal of China Textile University(English Edition)》 EI CAS 1998年第2期25-27,共3页
The study and the practical utilization of the infrared inthe textile field is analysed simply.The test method ofthe infrared transmittance(α_T)and the reflectance(α_R)in the fabric is introduced.The test results of... The study and the practical utilization of the infrared inthe textile field is analysed simply.The test method ofthe infrared transmittance(α_T)and the reflectance(α_R)in the fabric is introduced.The test results of aset of polyester/cotton plain fabrlcs show that the infra-red reflecting regulation can be expressed by quasi-co-sine function.The parameters affecting the α_T and α_Rare analysed, α_T decreases according to negative expo-nent function as the weight per square meter of the fab-ric increases,and α_R increases.Both α_T and α_R will in-crease when the mode of wavelength(λ_m) of the infra-red decreases.It can be deduced that the infrared ab-sorptance of the fabric will increase as λ_m increases inthe studied range. 展开更多
关键词 infrared TRANSMITTANCE reflectance MODE of the wavelength.
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Preparation of Cr_2O_3-based pigments with high NIR reflectance via thermal decomposition of CrOOH 被引量:8
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作者 梁书婷 张红玲 +4 位作者 雒敏婷 刘红霞 白玉兰 徐红彬 张懿 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第8期2646-2652,共7页
In order to reduce greenhouse gas emission and urban heat island mitigation, pure and titanium(Ti)-doped Cr2O3 cool pigments were prepared via the thermal decomposition of CrOOH. The result reveals that the pure Cr2... In order to reduce greenhouse gas emission and urban heat island mitigation, pure and titanium(Ti)-doped Cr2O3 cool pigments were prepared via the thermal decomposition of CrOOH. The result reveals that the pure Cr2O3 pigment presents both a high near-infrared reflectance and excellent yellowish-green color. Meanwhile, titanium was doped to improve the NIR reflectance and strengthen the color. The color of the designed pigments was brighter, and most importantly, the NIR reflectance increased from 84.04% to 91.25% with increasing Ti content from 0 to 0.006% (mole fraction). However, excessive doping of Ti4+ for Cr3+ in Cr2O3 (x(Ti)≥0.008%) decreased the NIR reflectance. One possible reason is that the conductivity type of the Cr2?xTixO3+δ changed from p-type conduction to n-type conduction with increasing Ti content, accompanied by the change of the electrical resistivity and the NIR reflectance. The prepared yellowish-green Cr2O3 pigments have a great potential for extensive applications in construction and military. 展开更多
关键词 CrOOH CrOOH cool pigments nir reflectance
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Near-infrared spectroscopy method for rapid proximate quantitative analysis of nutrient composition in Pacific oyster Crassostrea gigas 被引量:1
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作者 Zhe LI Haigang QI +4 位作者 Ying YU Cong LIU Rihao CONG Li LI Guofan ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2023年第1期342-351,共10页
Glycogen,amino acids,fatty acids,and other nutrient components affect the flavor and nutritional quality of oysters.Methods based on near-infrared reflectance spectroscopy(NIRS)were developed to rapidly and proximatel... Glycogen,amino acids,fatty acids,and other nutrient components affect the flavor and nutritional quality of oysters.Methods based on near-infrared reflectance spectroscopy(NIRS)were developed to rapidly and proximately determine the nutrient content of the Pacific oyster Crassostreagigas.Samples of C.gigas from 19 costal sites were freeze-dried,ground,and scanned for spectral data collection using a Fourier transform NIR spectrometer(Thermo Fisher Scientific).NIRS models of glycogen and other nutrients were established using partial least squares,multiplication scattering correction first-order derivation,and Norris smoothing.The R_(C) values of the glycogen,fatty acids,amino acids,and taurine NIRS models were 0.9678,0.9312,0.9132,and 0.8928,respectively,and the residual prediction deviation(RPD)values of these components were 3.15,2.16,3.11,and 1.59,respectively,indicating a high correlation between the predicted and observed values,and that the models can be used in practice.The models were used to evaluate the nutrient compositions of 1278 oyster samples.Glycogen content was found to be positively correlated with fatty acids and negatively correlated with amino acids.The glycogen,amino acid,and taurine levels of C.gigas cultured in the subtidal and intertidal zones were also significantly different.This study suggests that C.gigas NIRS models can be a cost-effective alternative to traditional methods for the rapid and proximate analysis of various slaughter traits and may also contribute to future genetic and breeding-related studies in Pacific oysters. 展开更多
关键词 Pacific oyster Crassostrea gigas near-infrared reflectance spectroscopy(nirS) nutrient composition rapid determination
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Thermal Performance of Building Roof with Infrared Reflective Coatings 被引量:1
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作者 SHEN Hui,TAN Hong-wei,KATSUO MIKI,LIU Xiao-yu(Research Institute of HVAC and Gas Engineering,College of Mechanical Engineering,Tongji University,Shanghai 200092,China) 《湖南大学学报(自然科学版)》 EI CAS CSCD 北大核心 2009年第S1期151-155,共5页
This paper investigated the applicability and effects of infrared reflective coating on energy consumption of factory building in hot summer and warm winter zone.It first resorted to theoretical calculation,which demo... This paper investigated the applicability and effects of infrared reflective coating on energy consumption of factory building in hot summer and warm winter zone.It first resorted to theoretical calculation,which demonstrated the beneficial effects of infrared reflective coating on reducing building energy consumption.Then it analyzed a field measurement done on two identical rooms respectively with ordinary coated roof and infrared reflective coated roof from November 2006 to October 2007,on a 24h basis.The measured data include exterior and interior roof surface temperature,indoor air temperature,and indoor globe temperature.The related weather data is from a weather station near the measured area.The continuous measurement has been accomplished in southern China,and the measured data indicate that roof surface temperature and heat gain are significantly decreased in summer while slight negative effects in winter are induced by adopting infrared reflective coating.Thus it is simple and applicable to reduce building energy consumption in this area by applying infrared reflective coating.Regress equation between reduced roof thermal property,such as surface temperature and heat gain,and reduction in absorbed solar radiation shows their highly linear relationship.Based on the measured data,it is estimated that the reduced power consumption is 3.45 kWh/m2·month in June. 展开更多
关键词 infrared reflectIVE coating hot SUMMER and WARM WINTER zone measurement reflectIVITY
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