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961.
A governing equation describing the mass-transfer fluxes in practical membrane formation is derived using Markoffian and Onsager's thermodynamic systems. This equation unambiguously demonstrates that isothermal mass-transfer fluxes at the spinodal composition may not be zero for systems operated in the gravitational field. This study suggests that the mass transfer equations derived by Cheng and Gryte are a special case of the present study and are not fully capable of describing the mass transfer in practical membrane formation. Experimental results published in previous literature qualitatively support our assessment. The limitations of using Markoffian and Onsager's thermodynamic systems for membrane formation study are also reviewed. In conclusion, new thermodynamic theories for polymer solutions are needed to quantitatively describe the mass transfer fluxes in practical membrane formation. 相似文献
962.
用一种参数化的形式研究了弦上具有硬胶子纽结所导致的有效弦张量的增长,在此种形式下强子一强子碰撞中有效弦张量随碰撞能量的增加而增加是来自碰撞中微喷注的产生,这种机制既能解释强子一强子碰撞奇异夸克压低因嵶铀媾鲎材芰恐龆龅男形帜芙馐停澹澹蚊恢懈靡蜃佑肽芰拷莆薰氐南窒蟆 相似文献
963.
Y. Tai J. Murakami K. Saito M. Ikeyama K. Tajiri M. Watanabe S. Tanemura T. Mizota 《The European Physical Journal D - Atomic, Molecular, Optical and Plasma Physics》2003,24(1-3):261-263
Plasma desorption mass spectrometry has been applied to
characterization of dodecanthiol-passivated gold nanoparticles.
An overview of the experimental set-up and mass analyses for the
nanoparticles prepared in different conditions are shown. Mass
distributions were found to shift to higher mass regions with
increasing reaction temperature and reaction period. The results
are consistent with those of transmission electron microscopy
observations, UV-visible absorption spectra and also with a
reported laser desorption mass spectrometry. 相似文献
964.
In this paper, we investigate the numerical identification of the diffusion parameters in a linear parabolic problem. The identification is formulated as a constrained minimization problem. By using the augmented Lagrangian method, the inverse problem is reduced to a coupled nonlinear algebraic system, which can be solved efficiently with the preconditioned conjugate gradient method. Finally, we present some numerical experiments to show the efficiency of the proposed methods, even for identifying highly discontinuous parameters.This work was partially supported by the Research Council of Norway, Grant
NFR-128224/431. 相似文献
965.
966.
Ping‐Cheih Wang Chia‐Fen Lee Tai‐Horng Young Dong‐Tsamn Lin Wen‐Yen Chiu 《Journal of polymer science. Part A, Polymer chemistry》2005,43(7):1342-1356
Magnetic poly(methyl methacrylate) (PMMA)/poly(methyl methacrylate‐co‐methacrylic acid) [P(MMA–MAA)] composite polymer latices were synthesized by two‐stage soapless emulsion polymerization in the presence of magnetite (Fe3O4) ferrofluids. Different types and concentrations of fatty acids were reacted with the Fe3O4 particles, which were prepared by the coprecipitation of Fe(II) and Fe(III) salts to obtain stable Fe3O4 ferrofluids. The Fe3O4/polymer particles were monodisperse, and the composite polymer particle size was approximately 100 nm. The morphology of the magnetic composite polymer latex particles was a core–shell structure. The core was PMMA encapsulating Fe3O4 particles, and the shell was the P(MMA–MAA) copolymer. The carboxylic acid functional groups (COOH) of methacrylic acid (MAA) were mostly distributed on the surface of the composite polymer latex particles. Antibodies (anti‐human immunoglobulin G) were then chemically bound with COOH groups onto the surface of the magnetic core–shell composite latices through the medium of carbodiimide to form the antibody‐coated magnetic latices (magnetic immunolatices). The MAA shell composition of the composite latex could be adjusted to control the number of COOH groups and thus the number of antibody molecules on the magnetic composite latex particles. With a magnetic sorting device, the magnetic immunolatices derived from the magnetic PMMA/P(MMA–MAA) core–shell composite polymer latex performed well in cell‐separation experiments based on the antigen–antibody reaction. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 1342–1356, 2005 相似文献
967.
In quantum communication, the channel noise and the misalignment of the reference frames between the communication parties will lead to the failure of quantum state transmission. Here an alignment-free spatial-polarization hyperentanglement transmission scheme is provided for hyperentangled photons. In this scheme, before the spatial-polarization hyperentanglement is transmitted through the fiber channel, it is first encoded as a time-bin entanglement with the same polarization. After the photons pass through the noise channel, the polarization errors caused by reference frames misalignment and channel noise can be corrected by time-bin entanglement. In principle, by implementing this scheme, the communication parties can share the original hyperentangled state, and the success probability can approach unity. The scheme is robust to random channel noise and reference frames misalignment, and the decoherence effect caused by the misalignment of the reference frames between the communication parties can be completely suppressed by implementing this scheme. 相似文献
968.
Chen Zaiqing Liu Hui Xiong Qi Huang Xiaoqiao Tai Yonghang Shi Junsheng 《Optical Review》2023,30(1):50-60
Optical Review - The stereo image consisting of an achromatic image and a chromatic image (mixed stereo pair) can be fused as a three-dimensional (3D) color scene by human observers. It is said... 相似文献
969.
970.
Scanning electron microscopy has been extensively used for the material characterization of objects of artistic and archaeological
importance, especially in combination with energy dispersive X-ray microanalysis (SEM/EDX). The advantages and limitations
of SEM/EDX are presented in a few case studies: analysis of pigments in cross-sections of paint layers, quantitative analysis
of archaeological glass from the Roman period excavated in Ephesos/Turkey, and investigations on glasses with medieval composition
concerning their weathering stability and degradation phenomena. 相似文献