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21.
化学浸提法研究中药茯苓中活性铝的形态分布   总被引:1,自引:1,他引:1  
利用KCl、NH4Ac、HCl、NaOH四种浸提液对中药茯苓中铝的存在形态分别进行浸取溶出,采用分光光度法对不同形态的铝含量进行测定,得到茯苓中活性铝的形态分布,有机铝含量占总量的58.9%;胶态Al(OH)3占总量41.1%;浸提液中铝的回收率为97.0%~109.3%。  相似文献   
22.
辐照降解茯苓多糖效应研究   总被引:1,自引:0,他引:1  
采用扫描电镜、水溶性糖含量检测、紫外光谱、红外光谱等分析方法,系统研究了不同剂量60Co辐照处理对茯苓多糖的降解效应。结果表明,茯苓经辐照后,微观结构上颗粒变小、形状不规则,1000kGy和1200kGy处理出现平整切口;随着辐照剂量的增大,水溶性总糖、水溶性茯苓多糖增加,且1000kGy效应最显著;紫外光谱检测结果显示,1000kGy和1200kGy辐照处理有羰基生成;红外检测结果显示,800、1000、1200kGy辐照处理后羰基均明显增加,且1000kGy和1200kGy处理间的差异不明显;说明辐照茯苓后,茯苓多糖可有效裂解为以羰基类化合物为主且相对分子质量较小的物质,并呈剂量关系。  相似文献   
23.
In the last few years renewed attention has been paid to the study of light scattering from random media. This is due to the recent discovery of a phenomenon that dynamic light scattering from a fluctuating random medium may produce shifts of spectral lines, even when the source and the scattering medium are at rest relative to the observer. It has also been demonstrated that a similar phenomenon may occur in static light scattering from spatially random media without dynamic fluctuations. By the well-known analogy between the processes of scattering and radiation, these phenomena in scattering are found to be closely related to the correlation-induced spectral changes in the coherence theory which are often referred to as the Wolf effect. In this paper some recent developments are reviewed on research regarding the phenomena of changes in the spectrum of light induced by scattering from random media. Emphasis is placed on a number of up-to-date attempts for elucidating the effects of multiple scattering on these phenomena.This review was presented as an invited paper at the Symposium on Spectral Effects in Collective Phenomena organized as a satellite meeting of the Seventh Rochester Conference on Coherence and Quantum Optics, June 7–10 1995 (Rochester, NY).  相似文献   
24.
本文在目标函数是一致凸且采用Wolfe线搜索的条件下,给出无约束最优化问题的DFP算法的全局收敛性的几个充分性条件,并与「1」中的条件进行了比较。  相似文献   
25.
The first domestication of the dog occurred in East Asia, and major ancestor of the dog was a wolf subspecies, Canis lupus chanco. This finding derives from data on the nucleotide sequences of mtDNA and the frequency of genes controlling blood protein polymorphisms in various subspecies of wolves and dog breeds around the world. The results of the allele frequency distribution of genes controlling 16 blood protein polymorphisms, and the incidence of dogs possessing erythrocytes with high potassium (HK) in Japan, East Asia and Europe allowed us to posturate the following hypothesis about the origins of Japanese dogs and the history of their development. In the Jomon period the first dogs entered the Japanese archipelago from southern or northern continental Asia. These dogs eventually spread throughout Japan. Then, during the Yayoi and Kofun periods, other dogs were brought over via the Korean Peninsula, and crossbreeding occurred with the original dogs. The resulted offspring can be assumed to be the ancestors of most of the Japanese breeds that exist today. Ethological studies have revealed a significant breed difference in behavioral traits among canine breeds with Japanese dogs, showing more aggressive dispositions than most of European dogs.  相似文献   
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The main goal of this paper is to give a characterization of Wolf, Schechter, and Browder essential spectra of (2 × 2) matrix operator on a Banach space. Furthermore, we apply the obtained results to transport equations. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
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