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51.
Effects of maturation and storage on solubility,emulsion stability and gelation properties of isolated soy proteins 总被引:11,自引:0,他引:11
J. J. Yao K. Tanteeratarm L. S. Wei 《Journal of the American Oil Chemists' Society》1990,67(12):974-979
Solubility, emulsion stability and gelation of isolated soy proteins and their 7S and 11S fractions from three stages of seed
maturity were studied. The pH-solubility profile was similar irrespective of maturation and six-month storage. The 11S protein
was more soluble in the acidic pH range than the 7S protein. Oil-in-water emulsion stability of isolated soy protein from
mature soybeans was higher than that from the immature ones. This is due to the fact that there was more 7S fraction in the
mature soybeans, and 7S protein was found to form a more stable emulsion than that formed from 11S protein. The result suggests
that isolated soy protein from mature soybeans would serve as a better emulsifying agent. Heat-induced soy protein gels became
weaker as the soybeans became more mature. This can be attributed to the higher content in the immature soybeans of 11S fraction
which gives a stronger gel than 7S fraction in the protein from immature soybeans. 相似文献
52.
五类电缆的工艺设计与制造 总被引:2,自引:0,他引:2
淮平 《光纤与电缆及其应用技术》2001,(6):20-23
介绍了局域网用五类电缆的性能要求、工艺设计及制造方法,并指出了五类电缆的市场前景。 相似文献
53.
54.
针对西门子S7-300可编程控制器的脉冲输出功能,将25个半音阶音符的周期及对应的脉冲数存放S7-300相应的内存单元中,通过合理分配S7-300的I/O端口,设计了一种音乐演奏控制系统.在硬件电路和软件编程的基础上,结合Wincc flexible仿真软件进行仿真与调试,实现了音乐演奏系统的功能需求.实践表明,该设计具有功能强、运用灵活、可靠性高、稳定性好、编程简单、使用方便以及体积小、功耗低等特点. 相似文献
55.
Among the new materials currently employed as electron donor element in active layers of organic solar cells (OSCs), PTB7 holds the best results. It has been extensively studied and now there is a search for new derivatives to improve its properties. In this work, a set of 24 polymers derived from polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7) was studied theoretically, using chemical modifications in the benzodithiophene (BDT) moiety of the PTB7 monomeric units. After evaluations of the electronic and optical properties, including the open circuit voltage and exciton dissociation and recombination conditions, the results indicate that employing chlorine as substituent yields the most promising material for application in active layers together with Phenyl-C61-Butyric-Acid-Methyl-Ester (PCBM) as electron acceptor material. 相似文献
56.
Yijian Jiang Ruyan Guo and A.S.Bhalla Institute of Laser Engineering Beijing University of Technology Beijing Materials Research Laboratory The Pennsylvania State University University Park PA USA 《中国激光》2008,(11)
Ta2O5 single crystals have been grown by the laser heated pedestal growth (LHPG) technique up to several centimeters length with diameter of 1.1 mm. The crystal, characterized by X-ray diffraction, dielectric measurement, and thermal expansion analysis, has Htri-Ta2O5 symmetry. Dielectric permittivity, loss tangent along [001] and [110] direction were investigated over the temperature range from -80 ℃ to 100 ℃. Large dielectric anisotropy in Ta2O5 single crystal was observed. At room temperature, the dielectric permittivities (1 MHz) along [001] and [110] are 33.2 and 231.9, respectively. The reason of dielectric enhancement in Ta2O5 crystal grown by LHPG was also discussed. 相似文献
57.
Samples of YBa2Cu3Ox (123) with excess Y2BaCuO5 (211) in the molar ratio of 5:1 ( 123/211) were processed using the “solid liquid melt growth” (SLMG) technique. The effect
of hold time above the peritectic on the magnetic properties was examined. Extended hold times above the peritectic during
processing degrade the magnetic properties of SLMG processed 123. In SLMG 123, the very fine (>100 nm) 211 particles produced
by this processing route are the primarymagnetic flux pinners. Extended hold periods reduce the number and/or coarsen the
average size of these fine precipitates, resulting in a reduced magnetization. These results were compared to undoped Y123
processed by the more traditional melt texture growth (MTG). In MTG processing, extended hold times above the peritectic are
found to result in improved magnetic behavior because of increased defect densities. 相似文献
58.
The paper proposes that 1/f noise in materials and devices under non-equilibrium conditions is of electromagnetic origin rather than being related to charge carriers. For samples represented by simple resistors the analysis shows that the noise is due to the discrete nature of photons constituting the impinging electromagnetic flux from the source feeding the resistor. The paper presents detailed analysis of the external and internal electromagnetic fields of the resistor environment, with appropriate interpretation in terms of discrete photons. From quantum theory photons are known to retain their energy under interactions in linear environments. This property implies a departure from macroscopic electromagnetics in that photons cannot be partially transmitted and partially reflected, a phenomenon requiring appropriate modifications of boundary conditions at the resistor surface. These special demands call for inclusion of a supplementary internal resistor mode, serving as a lossless idler which is active only for matching purposes. At the resistor terminals the impinging photons give rise to excitation of RF current and voltage noise with an exact 1/f frequency distribution, which is in agreement with all available experimental measurements. The paper presents detailed formulae for noise spectral densities under general drive conditions from DC and RF sources of arbitrary internal resistance. The presented theoretical noise formulae have the same form as earlier empirical formulae for 1/f noise. With an RF source at frequency f0 the analysis predicts noise with 1/|f-f0| frequency distribution, which is compatible with available experimental observations. 相似文献
59.
介绍了5ESS交换机的软件补丁SU(Software Update)的基本知识,做SU前的准备工作,SU的安装过程和常见故障处理. 相似文献
60.