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991.
Egito AS Miclo L López C Adam A Girardet JM Gaillard JL 《Journal of dairy science》2002,85(4):697-706
The equine alpha(s1)- and beta-caseins (CN) were purified by chromatography on DEAE-cellulose and by reversed-phase HPLC. The alpha(s1)-, beta-, and kappa-CN were characterized either by monodimensional urea-PAGE or sodium dodecylsulfate (SDS)-PAGE or by bidimensional electrophoresis. Kappa-casein was characterized after electrophoresis by glycoprotein-specific staining. To identify alpha(s1)-CN without ambiguity, internal sequences were determined after trypsin or chymosin digestion of purified alpha(s1)-CN. These sequences, that could be estimated to correspond to 62% of the full protein, presented strong identities with regions of alpha(s1)-CN primary structures of other species. In particular, 51, 48, 43, and 40% identities were obtained with corresponding regions of sow, dromedary, cow, and human alpha(s1)-CN, respectively. On the other hand, trace amounts of equine gamma-CN-like and proteose peptone component 5-like peptides were found in the whole CN. They were identified by microsequencing and corresponded to beta-CN peptides generated by plasmin action on the whole CN. The equine alpha(s1), beta-, and kappa-CN were separated by bidimensional electrophoresis in numerous isoelectric variants with apparent isoelectric points distributed between pH 4.4 to 6.3, 4.4 to 5.9, and 3.5 to 5.5, respectively. The beta- and kappa-CN displayed a more acidic character in the mare than in the cow. 相似文献
992.
Oommen BS McMahon DJ Oberg CJ Broadbent JR Strickland M 《Journal of dairy science》2002,85(11):2750-2758
Low-moisture part-skim Mozzarella cheeses were manufactured from 2% fat milk and aged for 21 d. Treatments included cheeses made with one of three different strains of Lactobacillus delbrueckii ssp. bulgaricus in combination with a single strain of Streptococcus thermophilus. A fourth, control treatment consisted of cheeses made with only S. thermophilus. Although total proteolytic ability of these strains, as indicated by the o-phthaldialdehyde analysis, was similar in each of the three strains of L. bulgaricus, these strains exhibited different proteolytic specificities toward the peptide, alpha(s1)-CN (f 1-23). On the basis of their alpha(s1)-CN (f 1-23) cleavage patterns and a previously described classification, these strains were assigned to the groups I, III, and V. The objective of this study was to investigate the influence of lactobacilli proteolytic systems, based on specificity toward alpha(s1)-CN (f 1-23), on functionality of part-skim Mozzarella cheese. Moisture, fat, protein, salt-in-moisture, and moisture in nonfat substances content of cheeses made with groups I, III, and V strain were similar. Control cheese had a lower moisture content than did other treatments. Significant differences were observed in functional properties between cheeses manufactured using groups III and V strains. Cheeses made with groups I and III strains were similar in their meltability, hardness, cohesiveness, melt strength, and stretch quality. Meltability and cohesiveness increased with age, while melt strength and stretch quality decreased with age for all cheeses. Additionally, HPLC showed that total peak areas of water-soluble peptides derived from cleavage of alpha(s1)-CN (f 1-23) by different strains of lactobacilli could be highly correlated to meltability and stretch characteristics of cheeses made with those strains. 相似文献
993.
本文证明,被双缝衍射实验否定的是如下先入为主的假定:微观粒子通过某一条缝到达屏上某处的概率,与另一条缝是否打开无关。考虑到“概率的加法定理”,这种看法可表成:“当一个粒子束通过一个带有两条缝的隔板到达一个屏上时,在两条缝同时打开的条件下单个粒子落在屏上某处的概率,等于在两条缝轮流打开的条件下该粒子落在该处的两个概率之和。”把两条缝同时打开还是轮流打开这样的实验条件称为“通道条件”,则上述命题可表成“概率不依赖于通道条件”。 另一方面,按照上面的用语,量子力学中的“概率幅的迭加原理”应表成“概率幅不依赖于通道条件”。相应地,我们把“概率不依赖于通道条件”这一错误的命题称为“概率的迭加假定”。 由于没有引进“通道条件”,人们混淆了“概率的迭加假定”和“概率的加法定理”两个命题。经典物理学默认概率的迭加假定,从而不能理解双缝衍射实验;量子力学则相反,为了说明双缝衍射实验而否定概率的加法公式,从而遇到诠释上的困难。 任何替代量子力学解释量子现象的理论都得说明双缝衍射实验,这就必须引进通道条件或引进概率幅。而贝尔定理涉及的隐变量理论却不满足这一先决条件,因此,它必然与实验事实相矛盾。这样我们就重新发现了洛查克的论据:贝尔不等式与定域性原理无 相似文献
994.
A. A. Galyaev 《Automation and Remote Control》2006,67(6):856-867
The impact of a system of elastically linked material points against an absolutely rigid obstacle is analytically described and limit to an elastic homogeneous rod is studied. 相似文献
995.
A non-zero-approaching adaptive learning rate is proposed to guarantee the global convergence of Oja's principal component analysis (PCA) learning algorithm. Most of the existing adaptive learning rates for Oja's PCA learning algorithm are required to approach zero as the learning step increases. However, this is not practical in many applications due to the computational round-off limitations and tracking requirements. The proposed adaptive learning rate overcomes this shortcoming. The learning rate converges to a positive constant, thus it increases the evolution rate as the learning step increases. This is different from learning rates which approach zero which slow the convergence considerably and increasingly with time. Rigorous mathematical proofs for global convergence of Oja's algorithm with the proposed learning rate are given in detail via studying the convergence of an equivalent deterministic discrete time (DDT) system. Extensive simulations are carried out to illustrate and verify the theory derived. Simulation results show that this adaptive learning rate is more suitable for Oja's PCA algorithm to be used in an online learning situation. 相似文献
996.
The component solubilities of the HCl–MgCl2–H2O system at 40 °C were calculated by using Pitzer’s ion-interaction model and the solubility equilibrium constant of HCl⋅MgCl2⋅7H2O at 40 °C was evaluated according to the solubility data for the HCl–MgCl2–H2O system at −19.8, 0, 20, 25 and 50 °C. This study can provide the parameters necessary for solubility prediction for the HCl–LiCl–MgCl2–H2O system at 40 °C and supply a theoretical basis for the manufacturing process which was proposed by Gao and employed to extract MgCl2⋅6H2O from salt lake brine. 相似文献
997.
T. Czibk Z. Dezs Cs. Horvth S. Lipcsei J. Vgh I. Ps 《Nuclear Engineering and Design》2006,236(22):2356-2364
In 2004 the Hungarian Paks NPP completed a project for upgrading the reactivity measuring system applied during reactor startup experiments. Almost all components of the previous system were replaced, only ex-core ionisation chambers remained unaltered. New hardware and software components were introduced for neutron flux signal handling, for data acquisition, as well as for measurement evaluation and data presentation. High-precision picoamper meters were installed at each reactor unit, current signals are handled by a portable signal processing unit. The system applies an accurate on-line reactivity calculation algorithm based on the point-kinetic model with six delayed neutron groups. Detailed off-line evaluation and analysis of startup measurements can be performed on the portable unit, as well.The paper describes the architecture, data acquisition modules, services and man–machine interface of the new system. Functions and results are illustrated with measured data recorded during a startup of Unit 3. In 2003 and 2004 the RMR was installed and tested at all Paks NPP units successfully and now it is in regular use during unit startups.The second part of the paper illustrates an extension of the new system to perform reactivity measurements using the well-known Rossi-α and Feynman-α statistical methods. The modified system was needed to estimate the reactivity of a subcritical system formed by damaged fuel assemblies stored at the fuel service pit of Paks Unit 2. Theoretical background of the applied algorithms is outlined, then results of validation tests and on site measurements are treated. The measurements have shown that the subcriticality of the damaged fuel was sufficiently deep if the high boron concentration in the fuel service pit was maintained. 相似文献
998.
U-Boot在S3C2410上的移植 总被引:1,自引:0,他引:1
bootloader是嵌入式系统中必不可少的用以完成系统的启动加载任务的一段软件代码。U-boot作bootloader的集大成者.现已得到了广泛的应用.本文通过将u—boot移植到基于s3c2410的开发板上详细地介绍了u-boot的运行原理和移植过程。 相似文献
999.
曹伟 《数字社区&智能家居》2005,(36)
本文简介了用vb6.0设计开发“标准化考试系统的制作”过程。它完成服务端对考生、考试科目、考试题目及答案等基本信息的浏览、查询、统计、注册等操作,完成了客户端学生考试和答案信息的反馈。主要讨论了制作的实施过程与教学设计方式以及制作中的若干问题,并提出了考试系统的标准化制作的整个流程模块,并给出了实例。 相似文献
1000.
湍流对部分相干光光谱移动的影响 总被引:18,自引:3,他引:18
Wolf效应,即部分相干光除满足定标律之外,即使在自由空间中传输时其光谱一般也会发生变化,是一类著名的相关诱导光谱变化现象。以高斯-谢尔模型(GSM)光束作为部分相干光的典型例子,研究湍流对高斯-谢尔模型光束光谱移动的影响。基于部分相干光的传输定理,并考虑湍流的存在,推导出了高斯-谢尔模型光束通过湍流介质的光谱公式,并作了数值计算。研究表明,无论定标律是否满足,湍流都会影响高斯-谢尔模型光束的光谱。湍流越强,与无湍流情况比较光谱移动越大。特别是,若不满足定标律时轴外光谱还会出现分裂。高斯-谢尔模型光束在湍流介质中的光谱移动由光束的空问相干性、折射率结构常数Cn^2和位置等参量决定。 相似文献