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961.
原子吸收法测定中药脑心通中微量和宏量元素的含量 总被引:1,自引:0,他引:1
采用原子吸收分光光度法测定了脑心通胶囊中钠、钾、钙、镁、铁、铬、锰、镍、镉、铜、锌11种元素的含量。结果表明,脑心通胶囊中含有较丰富的微量元素,为探讨中药脑心通中微量元素与治疗心脑血管疾病的关系提供了有用的数据。 相似文献
962.
963.
964.
实验光谱学和理论计算都发现,“重原子”能隔离分子中的某些振动能景,如SiH_4中Si—H振动泛频的“局域模”.Roger 等在研究F 原子与M(CH_2CH=CH_2)_4(M=Sn,Ge)的反应中,发现了Sn,Ge 对过剩能量转移到其它部分有强烈的阻碍作用(在中间态的寿命时间内).最近,在研究O(~1D)+M(CH_3)_4生成OH(v)反应中,观测到类似的现象.M=C 时,Lutz 用激光诱导荧光方法检测OH 的振动分布,振动是冷的,v=1与v=0的布居比为0.05, 相似文献
965.
966.
Li Xiaolin Tong Chunhan Zhu Jieqing Zhang Jiaohua 《Journal of Radioanalytical and Nuclear Chemistry》1995,198(2):385-392
In determining the trace platinum group elements and gold in rocks and ores by the neutron activation analysis after a nickel sulphide fire assay preconcentration, there are interferences due to nuclides produced from second order nuclear reactions. This paper presents the degree of interference calculated over the ranges of long irradiation times and of reactor neutron flux from 1·1013 to 1·1015 n·cm–2·s–1. According to the results of these calculations, every one of the second order interfering reactions on the PGE+Au, except the197Au(n, )198Au(n, )199Au reaction, can be neglected under the long irradiation time or high reactor neutron flux. Special attention is given to the interference from gold in the determining platinum. 相似文献
967.
Li Q Chen X Zhang H Xue C Fan Y Hu Z 《Fresenius' Journal of Analytical Chemistry》2000,368(7):715-719
Proteins can be determined using a common spectrofluorometer to detect the intensity of resonance light scattering (RLS). Under acidic conditions, the reaction between m-carboxychlorophosphonazo (CPA-mK) and proteins enhances the weak light scattering of CPA-mK drastically. This enhanced intensity is proportional to the concentration of proteins. The linear ranges for human serum albumin are 0.5-35.0 microg/mL, with detection limits of 0.104 microg/mL. The method yields results comparable to those of the calorimetric method using Coomassie Brilliant Blue G-250 (CBB) with relative standard deviations of 0.72-2.10% (n = 10). There is almost no interference by amino acids and most of the metal ions. 相似文献
968.
Potential alternative to petrochemical polymers, soy protein isolate (SPI), a plentily available, natural biopolymer is chemically
modified with thiourea at 2.5, 5, 7.5, 10, 15 and 20 mass/mass% for better processing of plastic as a raw material. From the
FTIR studies, it has been ascertained that there is no bonding reaction between SPI and thiourea and it acts as a modifier
only. Thermogravimetric analysis of the modified material has been followed using a computer analysis method, LOTUS package,
developed by us for assigning the degradation mechanism. A number of equations have been used to evaluate the kinetic parameters.
The mechanism of degradation of the biopolymer is explained on the basis of the kinetic analysis. 相似文献
969.
Using the polyglycol gel method, a series of Pr2 − x
SrxCoO4 ± y
(0.2 ≤ x ≤ 1.0) mixed oxides were prepared, and their catalytic activities were studied in the test reaction of NO reduction by CO.
The solid-state physicochemical properties, including crystal structure, defect structure, IR spectrum, valence state of B-site
ions, nonstoichiometry oxygen (y), oxygen species, and redox properties, were characterized by means of XRD, IR, TPD, TPR,
XPS, and chemical analysis. The results show that all mixed oxides display a K2NiF4 structure. When x = 0.2 and 1.0, the obtained samples still have little uncertain mixed oxides; however, the mixed oxides (x = 0.4, 0.6, 0.8) all represent a single A2BO4 phase. With the increase of x, lattice parameters, unit-cell volume, and average crystalline size decrease gradually, whereas microstrain density, the
concentration of Co3+, the amounts of lattice oxygen released and the concentration of oxygen vacancy increase. The catalytic activities of Pr2 − x
SrxCoO4 ± y
catalysts for NO reduction by CO are closely correlated with oxygen vacancy and the concentration of Co3+.
Published in Russian in Kinetika i Kataliz, 2006, Vol. 47, No. 3, pp. 431–437.
The text was submitted by the authors in English. 相似文献
970.
The compound Cs10.5[(V16O40)(Si4.5V1.5O10)].3.5H2O is the first example of an extended structure in which a polyoxometallate anion is linked by an extended tetrahedral unit. 相似文献