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41.
近年来 ,自组装及其形成的多层复合膜已经在导电、生物传感器及非线性光学等领域得到深入研究 ,特别是以聚阴离子与聚阳离子相互作用的静电自组装研究更为深入 .这一技术制备方法简单 ,无需特别的设备 ,对膜层厚度能随意调控 ,并以水作为介质 ,对环境无害 [1~ 3] .共轭高分子 (如聚苯胺、聚吡咯及聚苯亚乙烯等 )通过自组装形成共轭高分子膜 ,对制备具有导电、光电和传输等功能的薄膜半导体器件具有重要意义 .聚乙炔类是最早被发现且理论与应用研究最多的一类共轭高分子材料[4 ,5] .本文以聚 ( 4 -羧酸苯基 )乙炔 ( PCPA)为聚阴离子 ,以重… 相似文献
42.
Journal of Optimization Theory and Applications - In this paper, we study a general minimization vector problem which is expressed in terms of a perturbation mapping defined on a product of locally... 相似文献
43.
We provide a direct computational proof of the known inclusion
where
is the product Hardy space defined for example by R. Fefferman and
is the classical Hardy space used, for example, by E.M. Stein. We
introduce a third space
of Hardy type and analyze the interrelations among these spaces. We give simple sufficient conditions for a given function
of two variables to be the double Fourier transform of a function in
and
respectively. In particular, we obtain a broad class of multipliers on
and
respectively. We also present analogous sufficient conditions in the case of double trigonometric series and, as a by-product,
obtain new multipliers on
and
respectively. 相似文献
44.
Edwards KW Ogg M Bellerive A Britton DI Hyatt ER MacFarlane DB Patel PM Spaan B Sadoff AJ Ammar R Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kelly M Kotov S Kravchenko I Kwak N Lam H Kubota Y Lattery M Momayezi M Nelson JK Patton S Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Ling Z Mahmood AH O'Neill JJ Severini H Sun CR Wappler F Crawford G Daubenmier CM Fulton R Fujino D Gan KK Honscheid K Kagan H Kass R Lee J Sung M White C Wolf A Zoeller MM Butler F Fu X Nemati B 《Physical review letters》1995,74(17):3331-3335
45.
A new fusion agent is proposed for the analysis of cement and cement raw meal using AAS. In the described method, 0.8 g of the fusion agent, consisting of equal portions of oxalic acid, lithium carbonate and lithium tetraborate, was mixed with 0.2 g of the sample, and the mixture was fused for 10 min at 925 degrees C in a platinum crucilbe. The fusion cake was dissolved with dilute hydrochloric acid (1 + 10) and diluted to 500 ml for the determination of Si, Al, Fe, Ti, Na and K expressed as SiO(2), Al(2)O(3), Fe(2)O(3), TiO(2), Na(2)O, and K(2)O respectively. For the determination of Ca and Mg (expressed as CaO and MgO respectively), 10 ml of the previous sample solution were mixed with 4 ml of 6% (m/v) lanthanum nitrate solution and the solution was diluted to 100 ml. The method was found to have good accuracy and precision. The time required to determine the eight elements was around 80 min for each sample. 相似文献
46.
47.
Strachan JD Adler H Alling P Ancher C Anderson H Anderson JL Ashcroft D Barnes CW Barnes G Batha S Bell MG Bell R Bitter M Blanchard W Bretz NL Budny R Bush CE Camp R Caorlin M Cauffman S Chang Z Cheng CZ Collins J Coward G Darrow DS DeLooper J Duong H Dudek L Durst R Efthimion PC Ernst D Fisher R Fonck RJ Fredrickson E Fromm N Fu GY Furth HP Gentile C Gorelenkov N Grek B Grisham LR Hammett G Hanson GR Hawryluk RJ Heidbrink W Herrmann HW Hill KW Hosea J Hsuan H Janos A Jassby DL Jobes FC 《Physical review letters》1994,72(22):3526-3529
48.
49.
Ammar R Ball S Baringer P Bean A Besson D Coppage D Copty N Davis R Hancock N Kelly M Kwak N Lam H Kubota Y Lattery M Nelson JK Patton S Perticone D Poling R Savinov V Schrenk S Wang R Alam MS Kim IJ Nemati B O'Neill JJ Severini H Sun CR Zoeller MM Crawford G Daubenmier CM Fulton R Fujino D Gan KK Honscheid K Kagan H Kass R Lee J Malchow R Morrow F Skovpen Y Sung M White C Butler F Fu X Kalbfleisch G Ross WR Skubic P Snow J Wang PL Wood M Brown DN Fast J McIlwain RL Miao T Miller DH Modesitt M 《Physical review D: Particles and fields》1994,49(11):5701-5704
50.
Summary A critical issue in drug discovery utilizing combinatorial chemistry as part of the discovery process is the choice of scaffolds to be used for a proper presentation, in a three-dimensional space, of the critical elements of structure necessary for molecular recognition (binding) and information transfer (agonist/ antagonist). In the case of polypeptide ligands, considerations related to the properties of various backbone structures (-helix, -sheets, etc.; , space) and those related to three-dimensional presentation of side-chain moieties (topography; (chi) space) must be addressed, although they often present quite different elements in the molecular recognition puzzle. We have addressed aspects of this problem by examining the three-dimensional structures of chemically different scaffolds at various distances from the scaffold to evaluate their putative diversity. We find that chemically diverse scaffolds can readily become topographically similar. We suggest a topographical approach involving design in chi space to deal with these problems. 相似文献