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991.
This paper deals with mathematical study of diffusive fluid transport and distribution in human dermal parts. It accounts
the intracellular fluid which continuously flows through the skin shells in order to maintain fluid balance within the body.
A mathematical model is envisaged for this process and the finite element method (FEM) is employed to calculate the concentration
of the fluid at different skin layers. This estimation is analyzed in relation with other parameters of the tissue medium
and the atmosphere. 相似文献
992.
The third-order nonlinear optical (NLO) property of the α- and β- isomers of [Mo8O26]4? polyoxometallate ion were studied by DFT/TDDFT method. The second static hyperpolarisabilities, γiiii, γiijj and γmean were calculated by finite-field method as an extension of the usual DFT run, and the results suggest that without any ligands coordinated, the two isomer molecules in high symmetry own modestly large γ values (γmean ~5×10?32esu, 3×10?32esu, respectively), and the electronic properties of the two isomers were also studied by DFT method for the discussion of the origination of the NLO response, especially the unique effect of the molecular orbital ‘closed loops' on the NLO response. 相似文献
993.
《国际化学动力学杂志》2018,50(9):681-690
Group additivity methods simplify the determination of thermodynamic properties of a wide range of chemically related species involved in detailed reaction schemes. In this paper, we expand Benson's group additivity method to organosilanes. Based on quantum‐chemical calculations, the thermodynamic data of 22 stable silicon‐organic species are calculated, presented in the form of NASA polynomials, and compared to the available experimental data. Based on this theoretical database, a complete set of 24 Si‐ and C‐atom‐centered, single‐bonded and nonradical group additivity values for enthalpy of formation, standard entropy, and heat capacity at temperatures from 200 to 4000 K is derived through unweighted multivariate linear regression. 相似文献
994.
The ultrasonic extraction (UE) method of anthocyanin from Clitoria ternatea flowers using response surface methodology (RSM) was performed in this study. By using RSM, the objective is to optimise the extraction yield of anthocyanin from C. ternatea which is influenced by various factors, including the extraction temperature, time, ratio of solvent to solid and ultrasonic power. The empirical model was investigated by performing first-level optimisation in a two-level factorial design with Design Expert 7 software. In comparison with the conventional solvent extraction, UE showed a 246.48% better extraction yield and produced an anthocyanin extract with a radical scavenging activity of 68.48% at the optimised factors of 50°C, 150 min, 15 mL/g and 240 W. 相似文献
995.
将基于软铋矿BSO光折变晶体的非对称结构光寻址空间光调制器的内部功能实现过程进行合理划分,对其中的一个关键部分进行理论分析,得到相应脉冲响应函数的主要解析表达式,并对调制传递函数的空间频率响应受到绝缘层介电常数、晶体层厚度以及晶体层内电荷纵向分布等因素的影响进行了数值分析和讨论。讨论分析和补充验证实验表明,功能实现过程各组成部分之间有着紧密的内在联系,分析结果能够反映整个功能实现过程涉及的各主要因素对调制传递函数空间频率响应的影响。对于如何通过合理选择和优化材料特性、结构参数、工作条件等因素,提高此类空间光调制器调制传递函数的空间频率响应特性具有一定的指导意义。 相似文献
996.
A general method for the investigation of adsorption kinetics of nonlinear,nonisothermal systems, based on frequency response analysis, ispresented. It is based on the definition of higher-order frequency response functions (FRFs) on the adsorber and on the particle level. FRFs on the adsorber level can be estimated from experimentally measuredadsorber FR and used to calculate FRFs on the particle level,which can be further used for model identification, by comparison withtheoretical particle FRFs. The general procedure for calculation of particle FRFs from those of adsorber is given. Also, the generalprocedure for theoretical derivation of particle FRFs is given andillustrated with an example of nonisothermal adsorption governed bymicropore diffusion and film resistance heat transfer, as well as theprocedure for calculating unmeasured adsorber FRFs, which isillustrated with an example of a batch adsorber with volume modulation. 相似文献
997.
Yosuke Hisamatsu 《Tetrahedron letters》2007,48(4):617-621
A new macrocyclic host, which contains a 2,6-bis(oxazol-2-yl)pyridine unit and a 2,7-dialkoxynaphthalene unit tethered by the appropriate length of alkyl side chains is prepared. This host undergoes highly selective complex formation with an adenine nucleobase, accompanied by a fluorescence response in CHCl3 by a combination of multiple hydrogen bonding and π-π stacking interactions. 相似文献
998.
999.
Kazuyuki Takeda Yutaka Tabuchi Makoto Negoro Masahiro Kitagawa 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2009,197(2):242-244
A new approach to compensate rf-pulse transients is proposed. Based on the idea of the response theory of a linear system, a formula is derived to obtain the required excitation voltage profile back from the intended target rf-pulse shape. The validity of the formula is experimentally confirmed by monitoring the rf-field created inside the sample coil with a pickup coil. Since this approach realizes accurate rf-pulse shapes without reducing the Q-factor of the tank circuit of the probe, it can be used not only to suppress the transient tail of the rf-pulse, but also as a general concept for accurate rf-pulsing. 相似文献
1000.
It is shown that during the propagation of surface plasmon polariton (SPP) in the system of two touching spheres (or cones) when one is a metal and the other is a semiconductor, the conditions of strong localization of the surface wave are realized. At the point of contact, an essential decrease of the wavelength of the SPP is observed and the diffraction processes do not hinder its localization on the nanometric scale. As a result, wave fields increase anomalously. The considered phenomena open a new possibility to propose the experimental way for exploring the gigantic enhancement of the nonlinear optical response from a rough surface. 相似文献