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141.
扩散限制聚集与粘性指化图案的模拟研究顾健德,田安民,鄢国森(四川大学化学系,成都,610064)关键词DLA,粘性指化,计算机模拟大自然经常以非常奇妙的方式向人们展示其魅力,吸引人们不断去思考和探索.四川大学图书馆文献阅览室的玻璃顶棚上出现的粘性指化... 相似文献
142.
ZHANG Yifeng GUO Hong ZHANG Guangming YAN Xiuyun YIN Shougen ZHANG Zhengpu Institute of Taitai Pharmaceutical Co. Ltd Shengzhen China State Key Lab. of Functional Polymeric Materials for Adsorption Separation Institute of Polyme 《Chinese Journal of Reactive Polymers》2002,(1)
1. INTRODUCTION Fig.1 The Chemical Structure of Milupeinan As a new type of antibiotics Milupeinan, not only possesses antibacterial activities against a wide range of Gram-positive and Gram-negative bacteria, but also higgh stability under th… 相似文献
143.
Discovery of High-Pressure Basic Granulite Terrain in North China Archaean Craton and Preliminary Study 总被引:2,自引:0,他引:2
High-pressure basic granulite terrain of 2.65 Ga from Jiouhuai'an in the junction of the Hebei and Shanxi provinces was discovered and reported recently. The three metamorphic mineral assemblages and their mineral reaction texture of the basic granulites have been identified, which represent three main metamorphic episodes of 1.4—1.5 Gpa, 800℃; 0.7—0.9 Gpa, 820℃ and 0.5—0.6 Gpa, 700℃. Their steep decompressional clockwise P-T path implies that a late Archaean continental collision and sole thrusting event perhaps occurred in North China Craton. This is important to study petrogenesis of high-pressure granulites, composition and texture of deep crust in North China Craton, and early Precambrian collision tectonism. 相似文献
144.
Two new compounds from Zingiber officinale 总被引:1,自引:0,他引:1
Yu Zhao Qiao Feng Tao Rong Ping Zhang Chang Xin Zhou Hui Dou Shu Yun Shi Ye Cheng Xiao Lian Li Sun Su Zeng Ke Xin Huang Xiao Dong Zhang Xiao Kun Li 《中国化学快报》2007,18(10):1247-1249
A new cyclic diarylheptanoid,1,5-epoxy-3-hydroxy-1-(3-methoxy-4,5-dihydroxyphenyl)-7-(4-hydroxyphenyl)-heptane (1),as well as a new monoterpene,10-O-β-D-glucopyranosyl-hydroxy cineole (2) were isolated from the rhizomes of Zingiber officinale. The structures of compounds 1 and 2 were established based on their spectral data.In addition,the antioxidant activities of these compounds were also measured. 相似文献
145.
Kwak WJ Han CK Chang HW Kim HP Kang SS Son KH 《Chemical & pharmaceutical bulletin》2003,51(3):333-335
A new triterpenoid saponin, loniceroside C was isolated from the aerial parts of Lonicera japonica. Its structure was established to be 3-O-beta-D-glucopyranosyl hederagenin 28-O-alpha-L-rhamnopyranosyl (1-->2)-[beta-D-xylopyranosyl(1-->6)]-beta-D-glucopyranosyl ester by spectroscopic techniques and chemical transformations. Loniceroside C showed in vivo antiinflammatory activity against mouse ear edema provoked by croton oil. 相似文献
146.
应用分子动力学模拟了25 ℃和50 ℃时新型室温熔盐二(三氟甲基磺酸酰)亚胺锂[LiN(SO2CF3)2, LiTFSI]与尿素(摩尔比为1:3.6)体系的结构与动力学性质. 在两个温度下体系的微观结构基本相同, Li+的配位数约为5, 且都是与溶剂和阴离子中的氧原子发生配位. 对TFSI-的研究表明, 每个TFSI-只提供四个氧中的一个与Li+配位; 而且在Li+的配位层中, TFSI-具有顺、反和gauche 等不同的构象, 并且不同构象出现的几率会随着温度的改变而改变. 相似文献
147.
二甲基甲酰胺中四种钕盐的电导 总被引:3,自引:0,他引:3
通过电导测量研究了四种钕盐:Nd(CF3SO3)3、Nd(ClO4)3、Nd(NO3)3和NdCl3在极性非质子溶剂DMF中的电导性质.利用线性拟合方法求得在25 ℃下Nd(CF3SO3)3和Nd(ClO4)3的极限摩尔电导率分别为278.8和 280.7 S•cm2•mol-1.用间接方法求得Nd(NO3)3 与NdCl3 的极限摩尔电导率分别为297.2和287.3 S•cm2 •mol-1.在25~65 ℃温度范围内,Nd(CF3SO3)3和Nd(ClO4)3的电导率随温度呈线性变化. Nd(NO3)3和NdCl3的电导行为表现出明显的离子缔合. 相似文献
148.
头发锌含量测定的应用价值评价 总被引:1,自引:0,他引:1
以114例2-5岁儿童为对象,同时取其末梢血和头发,测定锌含量。以全血锌值为标准,评价头锌测定的应用价值。结果显示,头发锌测定的灵敏度可达86.1%,特异度为52.4%,符合率为73.7%。 相似文献
149.
Kun Zhao Shuqi Zhuang Zhu Chang Haiyan Songm Liming Dai Pingang He Yuzhi Fang 《Electroanalysis》2007,19(10):1069-1074
A sensitive amperometric glucose biosensor based on platinum nanoparticles (PtNPs) combined aligned carbon nanotubes (ACNTs) electrode was investigated. PtNPs which can enhance the electrocatalytic activity of the electrode for electrooxidating hydrogen peroxide by enzymatic reaction were electrocrystallized on 4‐aminobenzene monolayer‐grafted ACNTs electrode by potential‐step method. These PtNPs combined ACNTs' (PtNPs/ACNTs) surfaces were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The highly dispersed PtNPs on ACNTs can be obtained. The enzyme electrode exhibits excellent response performance to glucose with linear range from 1×10?5–7×10?3 mol L?1 and fast response time within 5 s. Furthermore, this glucose biosensor also has good reproducibility. It is demonstrated that the PtNPs/ACNTs electrode with high electrocatalytic activity is a suitable basic electrode for preparing enzyme electrodes. 相似文献
150.
A strategy for design of bioimprinted proteins with glutathione peroxidase (GPX) activity has been proposed. The proteins imprinted with a glutathione derivative were converted into selenium-containing proteins by chemical modifying the reactive hydroxyl groups of serines followed by sodium hydrogen selenide displacement. These selenium-containing proteins exhibited remarkable GPX activities and the GPX activities of reduction of H2O2 by glutathione (GSH) were found to be 101-817 U μmol−1, which approaches the activity of a selenium-containing catalytic antibody elicited by a hapten similar to our template. The steady state kinetic study for imprinted protein catalysis revealed Michaelis-Menten kinetics for both H2O2 and GSH, e.g. the pesudo-first-order rate constant kcat (H2O2) and the apparent Michaelis constant Km (H2O2) at 1 mM GSH were calculated to be 784 min−1 and 1.24×10−3 M, respectively, and the apparent second-order rate constant kcat (H2O2)/Km (H2O2) was determined to be 6.33×105 (M min)−1. The kinetics and the template inhibition showed that the strategy might be a remarkably efficient one for generating artificial enzyme with GPX activity. 相似文献