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111.
On the basis of previous papers,this work discusses the theory of composite fields composed of colored stratons.Varicus equivalent representations of the S-matrix elements are given.The formulae for the transition matrix elements between states involving baryons in the theory of Straton Model are derived.Finally,the field- current relations are extended to spin 1/2 baryons and their applications are discussed. 相似文献
112.
In this paper we introduce the concept of "same order" in the perturbution expansion of the quatized composite field theory which is different from single particle theory. For example, in the case of Q. E. D., "same order" is defined by means of a coupling constant, but here it closely relates the operators occuring in the B. S. equations. Feymann graphs of the "same order" are defined for different kinds of transitions in the composite field theory. Finally, we prove that guage invariance is a natural result as long as all "same order" Feymann graphs are calculated for an electromagnetic transition between composite particles. 相似文献
113.
114.
The two pure nucleonic mechanisms (the conventional sequential mechanism and the two-nucleon pion absorption-emission mechanisml[1]) are studied within a unified framework of Distorted Wave Impulse Approximation (DWIA). The distorted pion waves are obtained by solving the Klein-Gordon equation with the first-order optical potential. The difference between this approach and the eikonal approximation is showed. For the two-nucleon pion absorption-emission mechanism the effective Landau-Migadal interaction of Pines, et al.[2] is used for the two bound nucleons, the result is compared with that by using the Paris force. By combining theee two mechanism the O0 excitation functions for the DCX reactions to the isobaric analog states on the 14C, 18O, 26Mg and 42Ca are calculated and compared with the experimental data. 相似文献
115.
A new formula as a series of commutators of two axial vector currents and the nuclear Hamiltonian HS derived for estimating the 2β-decay nuclear matrix element without using explicitly the closure approximation. With a simple assumption of the nuclear wave function and the Hamiltonian HS, it is shown that the leading term in 2υ-2β decay matrix element vanishes and thus the smallness of 2υ-2β decay probability seems to be understood. 相似文献
116.
The ionized Lifetime of the hydrogen negativeion in a uniform electric field is again calculated by using improved perturbation theory.The choice of the H--ion wave function and the normalization of wave function of continuous state are discussed. The numerical calculations by using Rotenberg-Stein wave function with five parameters are performed. Comparison of our results with experimental results obtained by G. M. Stinson et al. is given. 相似文献
117.
Clerodane diterpenoids are widely distributed in nature and constitute one of the largest and, yet, still rapidly growing family of secondary metabolites. Of the relatively few clerodanes tested for biological activity, many were found to possess interesting antifeedant and medicinal properties and are potentially useful as insecticidal, antitumour, antifungal, antibiotic, anti-peptic ulcer, and psychotropic agents. The structural complexity and biological activity associated with this class of natural products have attracted extensive effort towards their total synthesis. In most of the reported syntheses, the synthetic sequence is specific to the target molecule. We have recently developed a versatile synthetic approach which is applicable to the synthesis of a large number of target molecules with minor modifications. The key operation of this approach is the face-selective Diels-Alder reaction of dienone ester 1. The successful application of this approach has culminated in the total synthesis of several cisclerodane diterpenoids. We have since made considerable improvement on this general synthetic approach, in terms of the overall efficiency, making use of compounds 2 and 3 as dienophiles. This newly developed general synthetic approach towards clerodane diterpenoids will be presented. 相似文献
118.
HO Kai-ming 《高等学校化学研究》2011,(2)
We designed and optimized a large number of the isomers of Si12+ at the level of density functional theory (DFT)-B3LYP/6-311++G(d) using the Gaussian 03 software package. An unambiguous structure of the Si12+ cluster is presented, whose IR spectrum agrees well with the experiment result. The most stable geometric structures of Gen+(n=2―15) clusters were determined by the all-electron PBE/DND method in DMol3 of the Material Studio Package, and compared with those of the corresponding Sin+ geometries. Most st... 相似文献
119.
本实验测量了C12(d,p)C13及Ca40(d,p)Ca41基态反应质子群的角分布和微分截面。氘核能量为13.3MeV,对C12和Ca40的反应,其测量角度范围分别为3°—167°和10°—164°,每隔2.5°或5°测量一点,其主要结果如下:(1)对于这两群质子,在主削裂峯附近的实验点和用简单Butler理论算得的理论角分布曲线都符合得相当好;理论计算数据对实验数据在主峯处归一;由此而定得的核能级参数与前人所得到的是一致的。(2)大角度区的实验截面数值没有减小到象Butler理论所要求的那样小,并有非常明显的次极大出现,其位置与Butler理论所预言的不一致;这些特点可以用扭曲波理论来解释,非氘核削裂机制也可能有部分贡献。(3)在C12(d,p)C13反应中,前角度区的截面有很大下降,而后角区则有明显的增加,这些现象都和Butler理论不一致;然而,这也可以用扭曲波来解释。(4)用主峯处的截面和Butler理论算得的基态的约化宽度,对C12(d,p)C13和Ca40(d,p)Ca41反应分别为r2=0.17和0.041;用扭曲波理论计算时,则得到较大的r2值,后者更接近于单粒子模型所预言的数值,基于上面这些事实,对本实验的数据使用扭曲波理论来进行分析似乎是值得的。 相似文献
120.
Bicomponent aqueous solutions of copper and nickel ions have been used to investigate the sorption of metal ions onto peat. Peat, a low cost sorbent, has shown a high capacity for the sorption of single component metal ions attributed to extensive carboxylic acids within its structure. Copper and nickel ions were selected as typical metals in the effluents of electroplating industries. The effects of competitive sorption in batch systems were studied at various metal ion concentrations. In this study the Butler and Ockrent model was modified using a coefficient, . Two models were developed based on the interaction coefficient . The first model incorporates a constant fixed factor for each metal ion into the Butler-Ockrent equation. The second model incorporates a variable factor into the Butler-Ockrent equation; this interaction factor varies as a function of sorbent surface coverage. Predicted equilibrium data are found to be in excellent agreement with experimental values using both modified models for various mole ratios of copper and nickel ions in competitive sorption. 相似文献