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21.
本文较为全面地综述了Gaussian-1, Gaussian-2(简称G1,G2)理论以及简化的G2 CMP2 ) ,G2 (MP3)理论,将其主要结果进行了比较分析。关于G2理论的应用,除了较为详细地综述了几年来理论在重现实验数据、评价实验数据、预测实验数据及研究化学反应途径等方面的应用外,还结合我仁近期研究结果的主要结论讨论了该理论在研究等电子一等自旋,价层等电一等旋,等旋及非等旋化学反应的能量计算中的应用情况,以及该理论在预测化合物的标准生成蛤方面的应用情况。 相似文献
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本文研究了俘获于掺杂VO++离子的(NH4)2Zn(SO4)2·6H2O单晶中NH3+自由基离子的ESR.从实验上分别测出π电子自由基NH3+的14N和15N核超精细分裂.结果表明,氮核超精细偶合张量具有近似于圆柱形对称。对于15N来说,A11=44.8,A22=19.3,A33=17.8高斯.对于14N来说,A11=31.1,A22=12.5,A33=11.8高斯.在室温下,NH3+自由基绕A11方向作圆锥体运动.文中最后讨论了NH3+自由基离子的可能生成机理。 相似文献
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Auslender, Cominetti and Haddou have studied, in the convex case, a new family of penalty/barrier functions. In this paper, we analyze the asymptotic behavior of augmented penalty algorithms using those penalty functions under the usual second order sufficient optimality conditions, and present order of convergence results (superlinear convergence with order of convergence 4/3). Those results are related to the analysis of pure penalty algorithms, as well as augmented penalty using a quadratic penalty function. Limited numerical examples are presented to appreciate the practical impact of this local asymptotic analysis.This research was partially supported by NSERC grant OGP0005491 相似文献
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We introduce the set of bicomplex numbers
which is a commutative ring with zero divisors defined by
where
We present the conjugates and the moduli associated with the bicomplex numbers. Then we study the bicomplex Schr?dinger equation
and found the continuity equations. The discrete symmetries of the system of equations describing the bicomplex Schr?dinger
equation are obtained. Finally, we study the bicomplex Born formulas under the discrete symmetries. We obtain the standard
Born’s formula for the class of bicomplex wave functions having a null hyperbolic angle. 相似文献
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Adams JE Cox JR Christiano AJ Deakyne CA 《The journal of physical chemistry. A》2008,112(30):6829-6839
The unexpected sorption of gases by a low-density p-tert-butylcalix[4]arene crystal polymorph raises fundamental questions about differential gas transport and sequestration in the organic solid state. To gain insight into the processes underlying these observations, we have used molecular dynamics simulations, augmented with calculations of potentials of mean force, to investigate the stability of isolated host-guest complexes and the relationship between the dynamics of these complexes and the dynamics of a solvated host molecule. Thermal fluctuations of the calixarenes themselves are found to be consistent with proposed mechanisms for gas entry into the host cavities, while relative host-guest stabilities correlate well with experimental absorption-desorption isotherms in some cases (CO2 and CH4) but not in others (C2H2). In these isolated systems, stable complexes characteristically form when the attractive interactions of the guest with the ring of negative charge density on the inner surface of the host cavity are not disrupted by thermal motion. The experimentally observed efficient uptake of gases such as C2H2 by the host crystals suggests, however, that stabilization of host-guest complexes in some systems may derive from dynamical constraints imposed by the crystal lattice. 相似文献
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使用含时密度泛函理论(TDDFT)B3LYP方法计算了IB, IIB, VIIIB过渡金属与8-羟基喹啉络合(MQ)后, 配合物的电子光谱以及二阶非线性光学性质. 结果表明, 掺杂过渡金属后, 形成络合物的能隙值减小100~150 kJ/mol, 最大吸收波长红移150~200 nm左右. 电子从基态到激发态的跃迁主要为p→p*, n→p*跃迁, 属于LLCT, MLCT过程. IB的络合物MQ以及VIIIB的络合物MQ3表现出良好的非线性光学性质. 相似文献