共查询到19条相似文献，搜索用时 35 毫秒
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近红外光谱法在连翘提取物含量测定中的应用 总被引：1，自引：0，他引：1
利用近红外光谱法(NIR)快速测定连翘提取物中连翘苷含量.应用近红外光谱仪采集75份连翘提取物样品的近红外漫反射光谱,通过HPLC(high performance liquid chromatography)法测定各样品中连翘苷含量,结合偏最小二乘法建立了连翘苷含量的定量校正模型.结果显示,决定系数、校正均方差和预测均方差分别为0.973 1、0.119和0.110,表明该方法快速、简便、无损.结果准确可靠,为连翘提取物质量的快速评价和在线检测提供了参考和依据. 相似文献
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为对草莓硬度进行预测研究,利用高光谱成像系统获取草莓的高光谱数据,光谱数据波长为400~1 000nm,采用标准正态变换（SNV）、多元散射校正（MSC）、卷积平滑方法（Savitzky Golay ）以及几种方法相结合对光谱数据进行预处理,选择最优的预处理方法,进一步结合化学计量学方法建立PLS预测模型,比较不同的光谱预处理方法对预测模型的效果,以选择最优预测模型。结果表明,经标准正态变换（SVN）处理后建立的偏最小二乘（PLS）模型效果最好,校正集和预测集的相关系数及均方根误差分别为0.989,0.882和0.021,0.073。因此,可采用高光谱成像技术对草莓硬度进行预测。 相似文献
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基于近红外光谱结合化学模式识别中的偏最小二乘法研究了一种快速、简单和低成本检测STR基因型的方法．选择STR基因座D5S818中的总串数相差较大的10—10、11—11与13—13基因型作为研究对象,将这三个基因型样本进行标准的PCR扩增并采集PCR产物的近红外光谱,以每一基因型的任意三分之二样本作为校正集,剩余三分之一作为预测集样本,探索了基于近红外光谱进行基因分型的可能性,结果发现该三类模型能够得到正确的判别,没有误判,预测集预测率达到100％．成功实现了基于近红外光谱对STR基因型的快速、简单和低成本检测． 相似文献
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采用化学方法测定了不同女贞子样品的蛋白质、脂肪和可溶性多糖含量,并对女贞子样品同时进行了近红外光谱测定.基于离散小波变换对女贞子近红外光谱的处理,探讨了同时测定女贞子蛋白质、脂肪和多糖含量的支持向量回归模型和偏最小二乘方法.结果表明:将离散小波变换与支持向量回归模型结合,可明显提高支持向量回归模型对女贞子样品中蛋白质、脂肪和可溶性多糖的预测准确度,结果满意. 相似文献
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近红外光谱法快速测定六味地黄丸中水分含量 总被引：1，自引：0，他引：1
采集不同厂家不同批号六味地黄丸样品的近红外光谱图,将其经First Derivative+MSC预处理,采用Savitzky-Golay平滑法(5点3阶数据平滑)处理,以滤去噪声,在7 819~4 038 cm-1谱段范围内,选择前10个主因子数,利用偏最小二乘法建立六味地黄丸的近红外光谱与药典参考方法测得的水分含量之间的相关模型。建立的水分定量校正模型相关系数R2=0.990 4,内部交叉验证均方差(RMSECV)=0.250 2,预测均方差(RMSEP)=0.099 7,平均回收率为100.75%。本实验所建模型性能较好,对六味地黄丸中水分含量有很好的预测能力,可实现大批量样品的快速检测,对中药制剂的质量分析有一定的参考价值。 相似文献
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校正变换矩阵法用于多组分染色剂的同时测定研究 总被引：1，自引：1，他引：0
将校正变换矩阵法(CTM)与可见分光光度法相结合,对藏红、荧光桃红、曙红三种染色剂进行不经分离同时测定.使用交叉验证法选择主因子数建立了校正模型,预测结果令人满意.在相同条件下,将校正变换矩阵法与偏最小二乘(PLS)回归的结果进行了比较,结果表明两种方法的预测准确性没有显著性差异. 相似文献
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周鑫 《数学学习与研究(教研版)》2015,(3):127
文章介绍了处理多元线性回归模型中多重共线性问题的有偏回归方法——岭回归和偏最小二乘回归,并通过实例比较了两种方法建立的回归方程的拟合效果,而偏最小二乘回归方法相对岭回归方法要更优. 相似文献
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偏最小二乘法用于阿昔洛韦片的近红外漫反射快速、无损含量测定 总被引：2，自引：0，他引：2
目的:采用偏最小二乘法结合近红外漫反射光谱,建立阿昔洛韦片的快速无损含量测定模型.方法:以阿昔洛韦片为分析对象,用光纤探头测定近红外漫反射光谱.对光谱进行不同预处理方法建模并进行比较,多元校正模型为偏最小二乘法.结果:在11995.5～4246.7cm-1波长范围内采用一阶导数结合矢量归一化对光谱进行预处理,结果最优.定量模型的浓度范围为27%～53%.预示集平均回收率为98.69%,RSD为4.60%,RMSEP为0.0526.结论:近红外漫反射光谱法快速,简便,无损,能够用于阿昔洛韦片含量测定. 相似文献
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在波长范围220-370nm,间隔0.2nm,测定了三种硝基甲苯异构体混合物乙醇溶液的吸光度数据,并用偏最小二乘法进行回归分析,结果显示邻硝基甲苯、间硝基甲苯和对硝基甲苯的回收率分别在98.225％-101.19％、100.25％-103.09％和99.547-100.94％之间.从计算结果可以看出,偏最小二乘法具有良好的预测效果,可用于多组分混合物的同时测定. 相似文献
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Application Fourier transform near infrared spectrometer in rapid estimation of soluble solids content of intact citrus fruits 总被引：1，自引：0，他引：1
Lu HS Xu HR Ying YB Fu XP Yu HY Tian HQ 《Journal of Zhejiang University. Science. B》2006,7(10):794-799
INTRODUCTION Soluble solids content (SSC) is a major charac- teristic used for assessing citrus fruit quality. Near-infrared spectroscopy (NIRS) has been used as a rapid and nondestructive technique for determining the soluble solids content of fruit. Kawano et al.(1992) measured sugar content of peaches in the wavelength region of 680~1235 nm. Their experiments indicated good correlation between the NIR spectra and the sugar content (r=0.97, SEP=0.05 °Brix). Slaughter (1995) devel… 相似文献
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INTRODUCTION Consumers’ acceptance of fresh or processedapples is the ultimate goal of apple breeders, foodscientists and supermarket managers. Internal qualityassessment has focused on two major objectives:removal of fruit with internal defects and taste selec-tion. Three major parameters including sugar content,acidity and firmness have to be taken into account todetermine the internal quality and the taste of an apple.Near infrared spectroscopy has been used to measureseveral properti… 相似文献
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To develop nondestructive acidity prediction for intact Fuji apples, the potential of Fourier transform near infrared (FT-NIR) method with fiber optics in interactance mode was investigated. Interactance in the 800 nm to 2619 nm region was measured for intact apples, harvested from early to late maturity stages. Spectral data were analyzed by two multivariate calibration techniques including partial least squares (PLS) and principal component regression (PCR) methods. A total of 120 Fuji apples were tested and 80 of them were used to form a calibration data set. The influences of different data preprocessing and spectra treatments were also quantified. Calibration models based on smoothing spectra were slightly worse than that based on derivative spectra, and the best result was obtained when the segment length was 5 nm and the gap size was 10 points. Depending on data preprocessing and PLS method, the best prediction model yielded correlation coefficient of determination (r^2) of 0.759,low root mean square error of prediction (RMSEP) of 0.0677, low root mean square error of calibration (RMSEC) of 0.0562. The results indicated the feasibility of FT-NIR spectral analysis for predicting apple valid acidity in a nondestructive way. 相似文献
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将小波变换（WT）与主成分回归（PCR）法相结合,对苋菜红、胭脂红、、诱惑红、赤藓红四种食用色素进行同时测定。选用Bior1．1小波对四组分混合物的原始吸光度数据进行一次分解,以低频系数作校正集并用交叉验证法选择主成分数进行PCR建模,获得了令人满意的预测结果。 相似文献
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INTRODUCTION Determination of fruit and vegetable quality is very important for both producers and processors. Watermelon as a delicious fruit has been widely ac-cepted in the world and its internal quality is impor-tant for consumers and merchants. The current fa-vorite way for checking a watermelon is to sense sound or vibration by slapping or rapping it. It is time consuming, tedious, and subject to error. Several studies on assessing the quality of watermelon based on its acoustic o… 相似文献
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主成分回归──光度法研究食用色素混合体系的同时测定 总被引：2，自引：0，他引：2
胭脂红、苋菜红、日落黄这三种食用色素的吸收光谱重叠严重。本文研究用主成分回归光度法解析普峰重叠体系,并对由这三种色素合成的混合样品进行了三组分的同时测定,结果令人满意,误差ASR％＜3．0％,回收率在97％～103％范围内。该法简便、快速、准确、无需预分离、可广泛地用于混合色素多组分的同时测定。 相似文献
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Yu Luo Wen-long Li Wen-hua Huang Xue-hua Liu Yan-gang Song Hai-bin Qu 《Journal of Zhejiang University. Science. B》2017,18(5):383-392
A near infrared spectroscopy (NIRS) approach was established for quality control of the alcohol precipitation liquid in the manufacture of Codonopsis Radix. By applying NIRS with multivariate analysis, it was possible to build variation into the calibration sample set, and the Plackett-Burman design, Box-Behnken design, and a concentrating-diluting method were used to obtain the sample set covered with sufficient fluctuation of process parameters and extended concentration information. NIR data were calibrated to predict the four quality indicators using partial least squares regression (PLSR). In the four calibration models, the root mean squares errors of prediction (RMSEPs) were 1.22 μg/ml, 10.5 μg/ml, 1.43 μg/ml, and 0.433% for lobetyolin, total flavonoids, pigments, and total solid contents, respectively. The results indicated that multi-components quantification of the alcohol precipitation liquid of Codonopsis Radix could be achieved with an NIRS-based method, which offers a useful tool for real-time release testing (RTRT) of intermediates in the manufacture of Codonopsis Radix. 相似文献
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The separation of ternary methanol/methyl butyl ether/1-butylchloride mixtures was investigated, which are the main components of the waste liquid. After preliminary studies on the ternary system, the integrated process of extraction and distillation was put forward to separate the ternary system. The results show that methanol carl be removed from the mixtures by extraction using water as the extracting agent. Through distillation of extract and dried raffinate respectively, methanol, methyl butyl ether and 1-butylchloride can be separated and recovered. In addition, the optimal volume for the extracting agent and effects of reflux ratio on the yield of product were also studied. The optimal volume ratio of the extracting agent to material is 1： 3.5, and the yield of the product increases with the increase of reflux ratio. 相似文献