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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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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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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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Rapid, Non-Destructive, Textile Classification Using SIMCA on Diffuse Near-Infrared Reflectance Spectra 被引量:1
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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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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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Determination of Active Components in a Natural Herb with Near Infrared Spectroscopy Based on Artificial Neural Networks 被引量:7
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作者 LIUXue-song QUHai-bin CHENGYi-yu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2005年第1期36-43,共8页
The non-linear relationships between the contents of ginsenoside Rg 1, Rb 1, Rd and Panax notoginseng saponins(PNS) in Panax notoginseng root herb and the near infrared(NIR) diffuse reflectance spectra of the herb wer... The non-linear relationships between the contents of ginsenoside Rg 1, Rb 1, Rd and Panax notoginseng saponins(PNS) in Panax notoginseng root herb and the near infrared(NIR) diffuse reflectance spectra of the herb were established by means of artificial neural networks(ANNs). Four three-layered perception feed-forward networks were trained with an error back-propagation algorithm. The significant principal components of the NIR spectral data matrix were utilized as the input of the networks. The networks architecture and parameters were selected so as to offer less prediction errors. Relative prediction errors for Rg 1, Rb 1, Rd and PNS obtained with the optimum ANN models were 8.99%, 6.54%, 8.29%, and 5.17%, respectively, which were superior to those obtained with PLSR methods. It is verified that ANN is a suitable approach to model this complex non-linearity. The developed method is fast, non-destructive and accurate and it provides a new efficient approach for determining the active components in the complex system of natural herbs. 展开更多
关键词 活性成分 天然药草 近红外线光谱分析 人工神经网络 非线性 PLSR 田七
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氢氧化钠分子结构原位漫反射一维及二维漫反射中红外光谱研究 被引量:1
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作者 于宏伟 吉一帆 +3 位作者 柴嘉欣 李阳 乔静 吴雨靓 《中国氯碱》 CAS 2024年第1期42-48,共7页
通过原位一维漫反射中红外(MIR)光谱开展了氢氧化钠分子结构研究。实验发现,氢氧化钠分子结构主要红外吸收模式包括OH基团伸缩振动模式(νOH-NaOH-_(一维))和OH基团面内摇摆振动模式(ρOH-NaOH-_(一维))。进一步开展了氢氧化钠分子结构... 通过原位一维漫反射中红外(MIR)光谱开展了氢氧化钠分子结构研究。实验发现,氢氧化钠分子结构主要红外吸收模式包括OH基团伸缩振动模式(νOH-NaOH-_(一维))和OH基团面内摇摆振动模式(ρOH-NaOH-_(一维))。进一步开展了氢氧化钠分子结构的原位二维漫反射MIR光谱研究。采用原位漫反射一维及二维漫反射MIR光谱开展氢氧化钠结构研究,对氯碱工业具有重要意义。 展开更多
关键词 原位漫反射一维中红外光谱 原位漫反射二维中红外光谱 结构 氢氧化钠
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Titanium dioxide as an adsorbent to enhance the detection ability of near-infrared diffuse reflectance spectroscopy 被引量:4
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作者 Shuyu Wang Jin Zhang +1 位作者 Wensheng Cai Xueguang Shao 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第5期1024-1026,共3页
A method for quantitative determination of fish sperm deoxyribonucleic acid(fsDNA)was developed by using titanium dioxide(TiO2)as an adsorbent and near-infrared diffuse reflectance spectroscopy(NIRDRS).The selective e... A method for quantitative determination of fish sperm deoxyribonucleic acid(fsDNA)was developed by using titanium dioxide(TiO2)as an adsorbent and near-infrared diffuse reflectance spectroscopy(NIRDRS).The selective enrichment of fsDNA was proved by comparing the adsorption efficiency of bovine serum albumin,tyrosine and tryptophan,and the low adsorption background of TiO2 was illustrated by comparing the spectra of four commonly-used inorganic adsorbents(alkaline aluminium oxide,neutral aluminium oxide,nano-hydroxyapatite and silica).The spectral feature of fsDNA can be clearly observed in the spectrum of the sample.Partial least squares(PLS)model was built for quantitative determination of fsDNA using 28 solutions,and 13 solutions with interferences were used for validation of the model.The results showed that the correlation coefficient(R)between the predicted and the reference concentration is 0.9727 and the recoveries of the validation samples are in the range of 98.2%-100.7%. 展开更多
关键词 near-infrared diffuse reflectance spectroscopy Quantitative model DETECTION ABILITY Titanium dioxide Fish SPERM DNA
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Determination of triglycerides in human serum by near-infrared diffuse reflectance spectroscopy using silver mirror as a substrate 被引量:1
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作者 Shuyu Wang Jin Zhang +3 位作者 Cuicui Wang Xiaoming Yu Wensheng Cai Xueguang Shao 《Chinese Chemical Letters》 SCIE CAS CSCD 2019年第1期111-114,共4页
Near infrared diffuse reflectance spectroscopy(NIRDRS) has gained wide attention due to its convenience for rapid quantitative analysis of complex samples. A method for rapid analysis of triglycerides in human serum u... Near infrared diffuse reflectance spectroscopy(NIRDRS) has gained wide attention due to its convenience for rapid quantitative analysis of complex samples. A method for rapid analysis of triglycerides in human serum using NIRDRS with silver mirror as the substrate is developed. Due to the even and high reflectance of the silver mirror, the spectral response is enhanced and the background interference is reduced.Furthermore, both linear and nonlinear modeling strategies were investigated adopting the partial least squares(PLS) and least squares support vector regression(LS-SVR), continuous wavelet transform(CWT)was used for spectral preprocessing, and variable selection was tried using Monte Carlo uninformative variable elimination(MC-UVE), randomization test(RT) and competitive adaptive reweighted sampling(CARS) for optimization the models. The results show that the determination coefficient(R) between the predicted and reference concentration is 0.9624 and the root mean squared error of prediction(RMSEP) is 0.21. The maximum deviation of the prediction results is as low as 0.473 mmol/L. The proposed method may provide an alternative method for routine analysis of serum triglycerides in clinical applications. 展开更多
关键词 near-infrared diffuse reflectance spectroscopy Silver MIRROR Variable selection Quantitative model SERUM TRIGLYCERIDES
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近红外光谱技术(NIRS)在草地生态学研究中的应用 被引量:17
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作者 聂志东 韩建国 +1 位作者 张录达 李军会 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2007年第4期691-696,共6页
近红外光谱技术(NIRS)是一种快速、高效、无损的现代检测技术,已经在许多领域广泛应用。文章阐述了NIRS应用于草地生态学研究的意义,介绍了NIRS用于测定牧草营养成分、矿物质、土壤养分含量,分析了牧草混合物的组成、动物对所采食牧草... 近红外光谱技术(NIRS)是一种快速、高效、无损的现代检测技术,已经在许多领域广泛应用。文章阐述了NIRS应用于草地生态学研究的意义,介绍了NIRS用于测定牧草营养成分、矿物质、土壤养分含量,分析了牧草混合物的组成、动物对所采食牧草的反应、牧草病虫害抗性等一些复杂特性,以及进行生化标记、同位素鉴别研究。综合这些研究可以看出,NIRS能够作为一种整体研究工具应用于草地生态学的许多研究领域中,可以检测各种常规化学成分、分析草地生态系统的各种动态指标和系统运行的多项整体特性。希望通过本文的总结分析,推动NIRS在中国草地生态学研究中的应用,加速该领域研究手段的现代化。 展开更多
关键词 近红外光谱技术(nirs) 生态 牧草 应用
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近红外光谱技术(NIRS)在检测牧草霉菌毒素中的应用 被引量:11
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作者 许庆方 韩建国 +1 位作者 玉柱 岳文斌 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2010年第5期1243-1247,共5页
具有快速、高效、无损、在线等优势的近红外光谱技术(nearinfrared reflectance spectroscopy technique,NIRS)已经在农业、食品、化工、医学等领域获得广泛应用。牧草在加工贮藏过程中,受多种真菌的侵染,引起霉菌毒素在牧草中积累。霉... 具有快速、高效、无损、在线等优势的近红外光谱技术(nearinfrared reflectance spectroscopy technique,NIRS)已经在农业、食品、化工、医学等领域获得广泛应用。牧草在加工贮藏过程中,受多种真菌的侵染,引起霉菌毒素在牧草中积累。霉菌毒素会通过动植物产品进入人畜的食物链,引起人畜中毒。牧草中霉菌毒素的常规检测不但需要粉碎、浸提、层析等繁琐的样品前处理过程,还需要酶联免疫吸附法、高效液相色谱法、溥层色谱法等后续检测过程。通过发展高精度、低检出限的光谱仪器,建立相应霉菌毒素检测的软件技术与校正模型,能够在牧草利用中达到快速准确检测霉菌毒素的含量和性质,从而为牧草的合理加工与利用提供依据,促进NIRS技术在健康畜产品生产领域的应用。 展开更多
关键词 近红外光谱技术(nirs) 霉菌毒素 牧草
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近红外反射光谱法(NIRS)测定棉仁粉中蛋白质和棉酚含量的研究 被引量:11
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作者 秦利 沈晓佳 +1 位作者 陈进红 祝水金 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2010年第3期635-639,共5页
选用49份不同蛋白质和棉酚含量的陆地棉种质资源和188份陆地棉重组近交系为材料,以多年份、多地点种植收获的种子材料组成原始样品集,分别对棉仁粉中蛋白质含量和棉酚含量进行化学测定,采用改进的偏最小二乘法(Modified PLS)和(2,4,4,1... 选用49份不同蛋白质和棉酚含量的陆地棉种质资源和188份陆地棉重组近交系为材料,以多年份、多地点种植收获的种子材料组成原始样品集,分别对棉仁粉中蛋白质含量和棉酚含量进行化学测定,采用改进的偏最小二乘法(Modified PLS)和(2,4,4,1)的数学转换方法建立近红外反射光谱(NIRS)定标模型,以寻找棉籽蛋白质含量和棉酚含量的快速测定方法。结果表明,蛋白质含量的定标决定系数(RSQ=0.933)和交叉检验决定系数(1-VR=0.929)较高,定标标准误差(SEC=0.623)和交互校验标准误差(SECV=0.638)较小,预测模型的建模效果较好,可替代化学分析。棉酚含量预测模型的RSQ,1-VR,SEC和SECV分别为0.836,0.811,0.074和0.079,模型预测效果略差于蛋白质模型,但仍可用于棉仁粉中棉酚含量的测定。 展开更多
关键词 近红外反射光谱(nirs) 棉仁粉 棉酚含量 蛋白质含量
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近红外光谱技术(NIRS)在反刍动物营养研究中的应用现状 被引量:8
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作者 郭旭生 尚占环 +1 位作者 方向文 龙瑞军 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2009年第3期641-646,共6页
近红外光谱技术(NIRS)分析样品时以其方便、快捷和准确等诸多优点在动物营养研究中得到了广泛的应用;用NIRS技术预测家畜日粮中有机物消化率时所产生的标准偏差(SECV)在1.6%~2.8%之间,而预测干物质的消化率时所产生的SECV在1... 近红外光谱技术(NIRS)分析样品时以其方便、快捷和准确等诸多优点在动物营养研究中得到了广泛的应用;用NIRS技术预测家畜日粮中有机物消化率时所产生的标准偏差(SECV)在1.6%~2.8%之间,而预测干物质的消化率时所产生的SECV在1.6%~3.5%之间。NIRS能够准确地预测饲料中的化学成分和生物学组分以及反刍家畜十二指肠微生物蛋白的流量,但对于预测饲料在瘤胃降解率的动态特性时与实际相差很大。NIRS技术预测舍饲家畜采食量与体内法得到的结果相似,但在预测放牧家畜采食量时其预测误差为14%左右。上述结果表明,NIRS技术在预测反刍家畜消化代谢、日粮营养评价、采食量等方面已取得了很大的进展,并在反刍动物营养研究领域中有着广阔的应用空间。 展开更多
关键词 近红外光谱技术(nirs) 消化率 采食量 食性 反刍动物
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基于NIRS技术的复合化肥成分定量分析及应用研究 被引量:7
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作者 宋乐 张红 +5 位作者 倪晓宇 吴林 刘斌美 余立祥 王琦 吴跃进 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2014年第1期73-77,共5页
提出了一种基于近红外漫反射光谱测定复合肥料中尿素、缩二脲和水分等成分含量的新方法。文中在对原始光谱进行预处理后建立了检测这三种成分含量的偏最小二乘(PLS)模型,其检验决定系数R2值分别为0.986 1和0.971 3,所建立模型的交互验... 提出了一种基于近红外漫反射光谱测定复合肥料中尿素、缩二脲和水分等成分含量的新方法。文中在对原始光谱进行预处理后建立了检测这三种成分含量的偏最小二乘(PLS)模型,其检验决定系数R2值分别为0.986 1和0.971 3,所建立模型的交互验证均方根误差RMSECV分别为2.59,0.38,0.132,模型预测相关因子分别为0.973 3,0.921 5,0.967 9;从市售的复合化肥中选取六种样品验证模型的准确性,其相关因子分别为0.923 7,0.978 6,0.987 4。研究结果表明,该方法可以对复合肥料中尿素、缩二脲和水分等成分含量进行快速测定,与传统分析方法相比具有分析时间短、操作简便、环保无污染等优点,有较好的应用前景和实际意义。 展开更多
关键词 近红外光谱 漫反射 复合肥料 尿素 缩二脲 水分 偏最小二乘模型
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FT-NIRS技术应用于稻米直链淀粉含量分析研究 被引量:10
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作者 张洪江 吴金红 +2 位作者 梅捍卫 黄芳 罗利军 《植物遗传资源学报》 CAS CSCD 2005年第1期91-95,共5页
运用近红外光谱快速分析技术,使用偏最小二乘法建立了近红外光谱和水稻糙米直链淀粉含量的数学模型,并进行糙米直链淀粉含量预测。结果表明糙米近红外光谱与其直链淀粉含量具有良好的相关性,决定系数r2=0.8429,最大绝对误差4.82%,平均误... 运用近红外光谱快速分析技术,使用偏最小二乘法建立了近红外光谱和水稻糙米直链淀粉含量的数学模型,并进行糙米直链淀粉含量预测。结果表明糙米近红外光谱与其直链淀粉含量具有良好的相关性,决定系数r2=0.8429,最大绝对误差4.82%,平均误差2.30%。该方法在不破坏样品的前提下快速分析水稻直链淀粉含量,可用于稻种资源的快速鉴定,对于水稻优质育种及其相关研究具有重要意义。 展开更多
关键词 含量分析 技术应用 直链淀粉含量 近红外光谱 稻米 快速分析技术 偏最小二乘法 数学模型 含量预测 平均误差 绝对误差 快速鉴定 稻种资源 相关研究 优质育种 糙米 水稻 相关性
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棉籽17种氨基酸含量的NIRS定标模型构建与测定方法研究 被引量:6
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作者 黄庄荣 陈进红 +1 位作者 刘海英 祝水金 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2011年第10期2692-2696,共5页
选用氨基酸含量差异较大的多年份、多品种、多地点种植的445份棉花种子为材料,分别对其进行近红外光谱扫描。用一阶导数的数学处理(1,4,4,1)、标准正态变换和去趋势(SNV+D)最佳组合的预处理方法,结合改良的偏最小二乘法(MPL... 选用氨基酸含量差异较大的多年份、多品种、多地点种植的445份棉花种子为材料,分别对其进行近红外光谱扫描。用一阶导数的数学处理(1,4,4,1)、标准正态变换和去趋势(SNV+D)最佳组合的预处理方法,结合改良的偏最小二乘法(MPLS)构建棉籽17种氨基酸成分的近红外定标模型。定标结果表明,天冬氨酸、苏氨酸、谷氨酸、甘氨酸、丙氨酸、缬氨酸、异亮氨酸、亮氨酸、苯丙氨酸、赖氨酸、组氨酸和精氨酸等12种氨基酸含量的定标模型较好,其RPDc为3.735-7.132,外部检验,上为0.910-0.979,近红外光谱分析完全可以替代化学测定;而丝氨酸、蛋氨酸、酪氨酸和脯氨酸等四种氨基酸的定标模型次之,其RP—Dc为2.205-2.814,外部检验r^2为0.800-0.830,近红外分析技术虽不能完全替代化学测定的结果,但仍可用于大量样品的筛选。半胱氨酸定标方程的RPDc较小(RPDc=1.358),因此,棉籽中半胱氨酸含量不能用近红外分析方法进行检测。 展开更多
关键词 棉籽 氨基酸 近红外反射光谱 定标模型
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近红外光谱技术(NIRS)在牧草领域中的应用研究进展 被引量:3
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作者 严旭 白史且 +2 位作者 鄢家俊 干友民 刀志学 《光谱学与光谱分析》 SCIE EI CAS CSCD 北大核心 2012年第7期1748-1753,共6页
牧草是草食动物最主要的营养来源。牧草品质的优劣不仅影响家畜的生长发育和生产效率,也决定着最终畜产品的产量与品质。牧草品质的优劣主要取决于牧草营养成分及其消化率、适口性、以及牧草中所含抗营养因子和真菌毒素、霉菌毒素的含... 牧草是草食动物最主要的营养来源。牧草品质的优劣不仅影响家畜的生长发育和生产效率,也决定着最终畜产品的产量与品质。牧草品质的优劣主要取决于牧草营养成分及其消化率、适口性、以及牧草中所含抗营养因子和真菌毒素、霉菌毒素的含量水平。近红外光谱技术(NIRS)是一种低成本、快速、简单、无损的定性、定量分析技术,已在许多领域广泛应用。该文简要介绍了NIRS的原理和特点,详细综述了NIRS在牧草品质分析、牧草育种、牧草品种鉴定和性状分类中的应用。通过较全面综述NIRS在牧草领域中的应用现状,以期有助于NIRS在我国牧草领域中的发展。 展开更多
关键词 牧草 近红外光谱技术(nirs) 品质 育种 鉴定 分类
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应用近红外(NIRS)技术分析小样品油菜籽粒含油量及硫甙含量 被引量:4
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作者 张美华 刘丽 +1 位作者 俎峰 王敬乔 《南方农业学报》 CAS CSCD 北大核心 2013年第1期28-32,共5页
【目的】对193份甘蓝型油菜籽粒进行常量样品(3.0g)及小量样品(0.3g)含油量及硫甙含量近红外光谱分析技术(NIRS)分析和回归模型研究,以期在育种过程中建立实用的油菜小样品含油量及硫甙含量测定数学模型。【方法】利用NIRS对甘蓝型油菜... 【目的】对193份甘蓝型油菜籽粒进行常量样品(3.0g)及小量样品(0.3g)含油量及硫甙含量近红外光谱分析技术(NIRS)分析和回归模型研究,以期在育种过程中建立实用的油菜小样品含油量及硫甙含量测定数学模型。【方法】利用NIRS对甘蓝型油菜籽粒进行含油量及硫甙含量测定,并进行回归分析。【结果】在众多回归模型中,对于小量样品籽粒含油量及硫甙含量,二次模型均为最优拟合模型,回归方程式分别为:y=40.190+0.892x-0.007x2(R2=0.970);y=-92.040+0.748x+0.002x2(R2=0.960)(y为常量测量结果,x为小量测量结果)。【结论】获得的二次回归方程式可以很好地将小量样品测定数据转化为常量样品分析结果,为高含油量和低硫甙油菜品种的选育奠定基础。 展开更多
关键词 近红外 甘蓝型油菜 含油量 低硫甙 回归分析
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NIRS结合TQ软件对氯化铵掺假牛奶定量分析 被引量:2
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作者 范睿 周勇 +5 位作者 孙晓凯 牛金叶 孙发哲 陈杰 孔玲 陈志伟 《安徽农业科学》 CAS 2017年第7期87-91,共5页
[目的]应用近红外光谱法建立氯化铵掺假牛奶定量分析模型。[方法]氯化铵是提高牛奶中含氮量的典型掺假物质,样品直接使用近红外光谱仪采用漫反射和三氯乙酸预处理后使用透射模块分别扫描并建立定量分析模型,并对模型进行验证。[结果]建... [目的]应用近红外光谱法建立氯化铵掺假牛奶定量分析模型。[方法]氯化铵是提高牛奶中含氮量的典型掺假物质,样品直接使用近红外光谱仪采用漫反射和三氯乙酸预处理后使用透射模块分别扫描并建立定量分析模型,并对模型进行验证。[结果]建立了漫反射氯化铵含量定量分析模型和透射氯化铵含量定量分析模型,后者模型更加准确可靠,均方根校正标准差(RMSEC)、相关系数(R2)、均方根预测标准差(RMSEP)分别为0.032 4、0.998 4、0.049 8,回收率为107.607 4%。[结论]三氯乙酸预处理后的透射模型更加精确,可以用于牛奶中氯化铵掺假检测,为进一步研究牛奶中其他物质掺假检测提供借鉴。 展开更多
关键词 牛奶 近红外 氯化铵 透射 漫反射
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聚光太阳能驱动二氧化碳甲烷化实验研究
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作者 孙帆 辛宇 +2 位作者 邢学利 洪慧 娄佳慧 《西安交通大学学报》 EI CSCD 北大核心 2024年第1期89-98,共10页
针对聚光光热驱动CO_(2)甲烷化反应过程中聚光的作用机制尚不清晰的问题,以具有优异反应活性及光热转换特性的Ni/Al_(2)O_(3)催化剂为研究对象,开展了聚光光热驱动和热驱动下的CO_(2)甲烷化实验及机理研究。通过表观活化能测试、温度梯... 针对聚光光热驱动CO_(2)甲烷化反应过程中聚光的作用机制尚不清晰的问题,以具有优异反应活性及光热转换特性的Ni/Al_(2)O_(3)催化剂为研究对象,开展了聚光光热驱动和热驱动下的CO_(2)甲烷化实验及机理研究。通过表观活化能测试、温度梯度实验及时间分辨的原位漫反射红外光谱实验,探究了聚光在反应过程中的作用机制,揭示了光热驱动CO_(2)甲烷化的反应机理。结果表明,与纯热驱动过程相比,光热驱动在相同温度下表现出更佳的催化性能。光热驱动下w(Ni)为15%的Ni/Al_(2)O_(3)催化剂在350℃下可达到86.8%的CO_(2)转化率,达到峰值转化率所需的温度比纯热驱动过程降低了25℃。此外,光热较热驱动过程的表观活化能降低了25%,且光致温度梯度进一步促进了CO_(2)的转化。时间分辨的原位漫反射红外光谱实验结果表明,聚光改善了CO_(2)在催化剂表面的吸附,促进了关键中间体的转变,增强了CO*生成CH4的反应路径,从微观动力学上促进了CO_(2)的转化。该研究为认识聚光太阳能驱动CO_(2)甲烷化过程中聚光的作用机制提供了新的思路。 展开更多
关键词 聚光太阳能 二氧化碳 甲烷化 原位漫反射红外
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