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121.
122.
碱溶法,原子吸收光谱直接测定人发、指甲的微量元素 总被引:9,自引:0,他引:9
居红芳 《光谱学与光谱分析》2002,22(4):681-684
本文探讨 2mol·L-1 NaOH溶液溶解人发、指甲 ,并在氘灯扣除背景下用火焰原子吸收法和石墨炉原子吸收法测定其中的Ca ,Zn ,Fe,Mn ,Ni,Cd ,Cu ,Pb ,Bi等元素 ,结果显示 ,所测元素含量与文献值基本相符 ,回收率除Bi偏低外 ,其它元素均在 90 0 %~ 110 8%内。并且发现人体的头发与指甲中所含元素含量没有对应关系 ,头发中所含元素含量高的 ,指甲中所含元素含量不一定高 ;头发中所含元素含量低的 ,指甲中所含元素含量不一定低 相似文献
123.
Tb, Ce, Eu activated oxyfluoride glass-ceramics with the composition SiO2 · Al2O3 · Li2O · LaF3 have been studied by cathodoluminescence (CL). We compared CL intensities and decay times of the Tb, Ce, Eu activated glass-ceramic samples and observed that the Tb activated sample has the most intense luminescence, but the Ce activated sample has the shortest decay times. Induced optical absorption and thermostimulated luminescence have been observed after X-ray irradiation of samples. 相似文献
124.
The structural characteristics of typical n+-on-p HgCdTe photodiodes have been studied by laser beam-induced current (LBIC). The dependence of LBIC on laser wavelength, junction depth and localized leakage has been presented. The diffusion length of minority carrier of p-type region is extracted by the exponential decay fitting of the curve of LBIC. It is found that the peak magnitude of LBIC and junction depth approximate to a linear relationship for practical values of device fabrication. The diffusion length monotonously increases with the junction depth. A notable shift of LBIC profile is observed when localized leakage exists. This provides a useful explain for LBIC applying to characterize the structure and process uniformity of HgCdTe infrared detectors. 相似文献
125.
In this paper, we will discuss the properties of solvable complete Lie algebra, describe the structures of the root spaces of solvable complete Lie algebra, prove that solvable Lie algebras of maximal rank are com-plete, and construct some new complete Lie algebras from Kac-Moody algebras. 相似文献
126.
二维纳米金单层膜的构建及其生物电化学应用 总被引:2,自引:0,他引:2
利用Langmuir-Blodgett (LB)技术在氧化铟锡(ITO)电极上制备了二维纳米金(nano-Au)单层膜,采用扫描电子显微镜表征了二维纳米金单层膜.实验结果表明:表面压为28 mN/m时,可获得分散性好、形状规则且分布均匀的二维球形纳米金单层膜.利用LB技术制备了肌红蛋白(Mb)薄膜,并将其固定在二维纳米金单层膜修饰的电极表面,研究了肌红蛋白LB膜的直接电化学行为.结果表明:纳米金粒子能够有效地加速肌红蛋白的电子转移,其电子转移速率为1.415 s-1. 相似文献
127.
Qian Guohua 《Proceedings of the American Mathematical Society》2004,132(7):1899-1903
Let be a finite group and the largest irreducible character degree of . In this note, we show the following results: if , then ; if and, in addition, is -solvable with abelian Sylow -subgroup, then .
128.
Lei Shen Qian-Qian Ma Qing Liu Tian-Tian Jia Yue Xu Ting Zhu Dun-Ru Zhu Jie Yang 《Journal of the Iranian Chemical Society》2018,15(3):637-647
Six new complexes [Mn8(μ4-O)4(phpz)8(MeOH)4]·(MeOH)(H2O) (1) [Co2(HphpzH)(Hphpz)2(phpz)2]·4(MeOH) (2), Ni(Hphpz)2 (3), [Ni(Hphpz)2]·H2O (4), [Zn4(pzpy)4Cl4] (5) and [Cu2(pzpy)2(HCO2)2(H2O)2] (6) have been synthesized by hydrothermal reactions of MCl2·4H2O (M = Mn, Co, Ni, Zn or Cu) with 5-(2-hydroxyphenyl)-3-pyrazole (HphpzH) or 2-(1H-pyrazol-3-yl)pyridine (Hpzpy). The complexes were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction. Complex 1 is an octanuclear Mn(III) cluster, complexes 2 and 6 are binuclear Co(III) and Cu(II), respectively, complexes 3 and 4 are isomorphous mononuclear species, while complex 5 is a tetranuclear Zn(II) cluster. The magnetic behavior of complex 1 was investigated. Magnetic susceptibility measurements revealed antiferromagnetic exchange interactions between the metal centers in the clusters. The luminescence properties of the complexes were investigated at room temperature in the solid state. 相似文献
129.
The multifractal analysis of relativistic shower particles produced in 32S–emulsion interactions at 200 AGeV has been investigated using the method of modified multifractal moments, Gq, in pseudo-rapidity space. The anomalous fractal dimension, dq, and generalized fractal dimensions, Dq, are determined for the present data for different order of moment. The experimental data reflects multifractal geometry in a multipion production process. The downward concave shape of the multifractal spectral function, f(αq), gives an evidence for self-similar cascade mechanism. The multifractal specific heat has also been evaluated for the present data using the generalized fractal dimensions, Dq. We compared our experimental results with those obtained from simulated events of the Lund Monte Carlo Code FRITIOF and uncorrelated Monte Carlo events, (MC-RAND) generated randomly in pseudorapidity space based on the assumption of independent emission of particles. The experimental data on multifractality has been found to exhibit a remarkable proximity to the analogous data obtained from the FRITIOF code and the uncorrelated Monte Carlo events. 相似文献
130.
In this paper, we investigate the stability and the shift between the extinction state and the stable one of a large density and the stochastic resonance (SR) for a metapopulation system subjected to two types of time delay terms, cross-correlation noises and multiplicative signal. By using the fast descent method and the method of small delay approximation, the expressions of the effective potential function and the signal-to-noise ratio (SNR) are obtained. We denote by Q the intensity of the multiplicative noise, and M the intensity of the additive noise, θ and τ the two time delay terms introduced into the metapopulation system. Our main results show some facts that time delay θ and the strength of correlation noise λ can restrain the development of the metapopulation, while the other term of time delay τ can accelerate the expansion of the population from the extinction state to the large stable one. We discover that it is possible to enhance the signal-to-noise ratio by adjusting the intensities of the multiplicative, additive noises and the time delays of the stochastic metapopulation system 相似文献