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11.
Co对Ni(OH)2电极中质子扩散行为的研究   总被引:2,自引:0,他引:2  
曹晓燕  周作祥 《电化学》1996,2(3):319-326
本文采用恒电位阶跃,循环伏安及恒电流放电池,考察含Co量0%-53%的Ni(OH)2电极充电过程中质子的扩散系数:充电过程该值为10^-9-10^-10cm^2/s,放电过程则为10^-11cm^2/s.数据处理时对文献中有关公式进行了修正。  相似文献   
12.
Density Functional Theory (DFT) studies on the ground states (2A'2) of NO3 radical and on the ground state (1A1') and the first triplet state (3E") of NO3 cation provide an unambiguous prediction about their geometrical structure-, the ground states of both NO3 radical and NO3 cation have D3h symmetry and the geometrical configuration of the first triplet state 3E" of NO3 cation has C2v symmetry. It is shown that as far as the ionization energy calculations on NO, radical are concerned, the results are only slightly different, no mater that gradient corrections of the exchange-correlation energy are included during self-consistent iterations or they are included as perturbations after the self-consistent iterations.  相似文献   
13.
The electronic and molecular structures of the monomer and dimer of trimethylalu-minium have been studied using density functional theory and ab initio MP2 method. The optimized geometry of the monomer Al(CH3)3 is of C3h symmetry, whereas that of the dimer [A1(CH3)3]2 contains a carbon-bridged four-membered ring structure with C2h symmetry. The hydrogen-bridged six-membered ring structure is found to be unstable. The calculated dimerization energy for the four-membered ring structure is 78 kJ/mol, in close proximity to the experimental value of 85.27 kJ/mol.  相似文献   
14.
采用微波消解-火焰原子吸收光谱法测定秦岭山区2种金粟兰属药用植物银线草和多穗金粟兰中铁、锌、铜、锰、钙、镁、钠、钾的含量。结果显示:银线草和多穗金粟兰中含有丰富的宏量和微量元素,银线草中所测元素含量依次为KCaNaMgFeZnMnCu,多穗金粟兰为KCaMgNaFeMnZnCu;所测得的8种元素中,银线草中的含量均高于多穗金粟兰,加标回收率在95.7%—108.2%之间,相对标准偏差(RSD)均小于5%。该方法简便、快捷、灵敏、准确,为探讨微量元素与银线草和多穗金粟兰的药效关系及进一步开发利用提供了理论依据。  相似文献   
15.
比较加入几种不同的混酸,用微波消解仪对土壤样品进行消解,采用双向视电感耦合发射光谱仪(DUO-ICP-AES)标准加入法(MSA)测定土壤中6项重金属元素含量。研究表明,HNO3-HClO4-HF-HCl处理土壤的效果比王水、HNO3-HF更佳,同时该法快速简单,回收率和精密度较好,干扰少,为土壤重金属含量的快速测定开辟了新方法。  相似文献   
16.
首次报导了1,2,5-噻二唑衍生物3-氯-1,2,5-噻二唑(A)和3,4=二氯-1,2,5-噻二唑(B)化合物的紫外光电子能谱(UPS),谱带的指认建筑在对谱带形状、相对强度、实验电离能(IPS)的分析以对研究分子Gaussian 94ST0-6G从头计算电离能(-ε1)。化合物B UPS谱带的IPS比相应的化合物A的IPS均你芝归结为B分子中两个取代C1原子上电子的拥挤效应。计算的B的 有量(  相似文献   
17.
The dynamical properties on reaction path (IRC) in internal coordinates have been obtained, which in. clude ω_K (frequencies orthogonal to IRC), L_K (vibrational modes), B_(KF) (coupling constants between the IRC and vibra tions orthogonal to it), B_(KL) (coupling constants between every two vibrations orthogonal to IRC). A set of theory of teac. tion path in molecular internal coordinates has been also constructed. The dynamical properties, including ω_K, B_(KF) B_(KL) of the reaction H~1O~2H~3 H~4→H~1O~2 H~3H~4 have been calculated, which explicitly explain the interaction, chang ing trend and contribution of each chemical bond (including bond angle) in the reaction.  相似文献   
18.
给出了分子内坐标下反应途径的动力学性质 ,即垂直于IRC的振动频率ωK和振动模式LK,这些振动模式与沿IRC运动的耦合常数BKF及它们之间彼此的耦合常数BKL.通过建立一套分子内坐标下的反应途径理论 ,以H1O2 H3 H4→H1O2 H3 H4反应为例 ,证明给出的这些动力学性质BKL,ωK,BKF清楚地说明了在化学反应中各化学键 (包括键角 )的相互作用、变化情况及各自对反应的贡献 .  相似文献   
19.
以有机化学实验中的蒸馏技术为实例,联系相平衡、界面现象等内容,组织讨论有机化学蒸馏实验中的物理化学知识点,旨在进一步培养学生的学习兴趣和科学的学习方法。  相似文献   
20.
The molecular constants of selected diatomic lanthanide compounds (LaH, LaO, LaF, EuH, EuO, EuF, EuS, GdO, GdF, GdH, YbH, YbO, YbF, YbS, LuH, LuO and LuF) have been calculated by using relativistic small-core pseudopotentials and optimized (14s13p10d8f6g)/ [6s6p5d4f3g] valence basis sets. The results are in good agreement with available experimental data, with exception of YbO and LuF. The reasons for the discrepancies in case of YbO are due to a complicated mixing of configurations in the ground state, whereas in case of LuF the binding energy estimated by experimentalists appears to be too low.  相似文献   
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