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991.
E Aida Pea‐Ramos Youling L Xiong Guillermo E Arteaga 《Journal of the science of food and agriculture》2004,84(14):1908-1918
Whey protein isolate (WPI) was hydrolysed for 1 h using Alcalase, Protamex and Flavourzyme. Native WPI, hydrolysed WPI and two commercial WPI hydrolysates were subjected to fractionation by size exclusion chromatography. Antioxidant activity of WPI fractions was measured with a liposome‐oxidising system (50 µM FeCl3/0.1 µM ascorbate, pH 7.0). Lipid oxidation was measured as thiobarbituric acid‐reactive substances (TBARS). Gel electrophoresis and amino acid analysis were run to identify the peptide composition. The influence of amino acid composition on antioxidant activity was evaluated using multivariate analysis methods (correlation analysis, principal component analysis, multiple linear regression and discriminant analysis). TBARS assays indicated the presence of antioxidant activity in all protein fractions, including non‐hydrolysed WPI. For native and hydrolysed WPI samples the first fraction (> 45 kDa) showed a higher TBARS inhibition effect (24–27%) when compared with lower‐molecular‐weight fractions and hydrolysate mixtures. In contrast, for commercial WPI hydrolysates a higher inhibitory effect was found in most of the lower‐molecular‐weight fractions (30–55%). The ability of WPI fractions to delay lipid oxidation was found to be related to the prevalence of histidine and hydrophobic amino acids. Copyright © 2004 Society of Chemical Industry 相似文献
992.
V Arvis B Michalet‐Doreau C Debain 《Journal of the science of food and agriculture》2004,84(14):1848-1854
We present a new computer vision method for measuring the physical characteristics of maize silages based on the extraction of image textural features, namely five Haralick features, the moments of order 1 and 2 on the grey levels of the image, and a fractal parameter. To show the effectiveness of these features for characterising the physical properties of the maize silage, a trial was performed on three maize cultivars (Zea mays L, a mid–early hybrid and an early hybrid) to study the effects of the ensiling process. The features could discern effects of the ensiling process on the physical properties of the maize silage. These effects were neither significant by comparing particle size distributions, nor with chemical compositions, whereas a biological response (degradation in the rumen) to the ensiling process exists. Thus image textural features seemed to give new and interesting measurements of the physical properties of the silage, explaining the biological response better than other methods. Furthermore, the ensiling effect was not the same with all the maize types and varied with the proportion of large particles in the silages. Linear relations between features before and after the ensiling process made it possible to predict a measure on a silage knowing its value on the parent forage. Copyright © 2004 Society of Chemical Industry 相似文献
993.
994.
勘探地球物理技术最新进展——2002年SEG年会综述Ⅱ:解释与压力预测 总被引:4,自引:4,他引:0
孙建国 《勘探地球物理进展》2003,26(2):148-159
根据2002年SEG年会部分论文编译而成,包括解释技术和压力预测技术。概要性地介绍了偏移成像技术;新属性技术;自动地震相分析技术;油气检测技术;储层反演技术和2种实用的压力预测技术。 相似文献
995.
余浩 《山东大学学报(工学版)》2003,33(3):337-340
分析了我国中医药数据分析作业方式的不足,试图通过建立网络数据分析中心,为中医药部门提供了一条实现网络化,标准化,信息化的思路. 相似文献
996.
底部框剪砌体房屋空间弹塑性地震反应分析 总被引:10,自引:3,他引:7
本文提出了底部框剪砌体房屋这类上下混合承重结构体系的空间弹塑性地震反应时程分析方法。针对砌体结构和框架抗震墙结构截然不同的抗震性能,对上部砌体结构采用空间剪扭分析法,而对下部框架抗震墙结构采用空间协同分析法,建立了组合型串联刚片系振动模型。对单向和双向地震波输入结构层位移反应进行了比较。 相似文献
997.
Specimen preparation and image processing and analysis techniques for automated quantification of concrete microcracks and voids 总被引:4,自引:0,他引:4
Parviz Soroushian Mohamed Elzafraney Ali Nossoni 《Cement and Concrete Research》2003,33(12):1949-1962
Specimen preparation and image processing/analysis techniques were developed for use in automated quantitative microstructural investigation of concrete, focusing on concrete microcracks and voids. Different specimen preparation techniques were developed for use in fluorescent and scanning electron microscopy (SEM) of concrete; then techniques produce a sharp contrast between microcracks/voids and the body of concrete. The image processing/analysis techniques developed specifically for use with concrete address the following usages: automatic threshold; development of intersecting microcracks/voids and connected voids; distinction of microcracks form voids based on geometric attributes; and noise filtration. 相似文献
998.
ANOM(均值分析)是一种有效的质量工具,可以用来分析实验因素对输出的影响是否显著。可以应用于单因子,双因子的实验设计,无论是计量值数据,还是计数值数据,ANOM检验异常值的能力都很强,介绍了ANOM的基本分析过程,对ANOM和ANOVA进行了检验异常值灵敏度大小的比较,同时给出了实例。 相似文献
999.
从目前市场需求和就业率出发,进行形势分析,提出优化专业设置、加强实践环节、提高高职学院办学层次、推进“双证书”制度等改革方法,以促进化工职业教育的发展。 相似文献
1000.
Alexander Vikhansky 《Chemical engineering science》2006,61(15):4966-4972
We consider two stochastic simulation algorithms for the calculation of parametric derivatives of solutions of a population balance equation, namely, forward and adjoint sensitivity methods. The dispersed system is approximated by an N-particle stochastic weighted ensemble. The infinitesimal deviations of the solution are accounted for through infinitesimal deviation of the statistical weights that are recalculated at each coagulation. In the forward method these deviations of the statistical weights immediately give parametric derivatives of the solution. In the second method the deviations of the statistical weights are used to calculate a finite-mode approximation of the linearized version of the population balance equation. The linearized equation allows for the calculation of the eigenmodes and eigenvalues of the process, while the parametric derivatives of the solution are given by a Lagrange formalism. 相似文献