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31.
Y. Tsuchiya Y. Nakajima T. Tamegai S. Nagasawa M. Hidaka 《Physica C: Superconductivity and its Applications》2011,471(21-22):808-811
We have observed flux penetrations into square superconducting networks of Nb with various thicknesses and hole-shapes by using magneto-optical imaging method. The penetrated pattern does not depend on the thickness and extends along diagonal direction when the samples have smaller area in the intersection of networks. We have also observed similar superconducting networks with and without small holes at the intersection. The small holes at the intersection do not work as a promoter for the diagonal flux penetration though the parallel flux penetration becomes weak. We discuss possible origins of these anomalous anisotropic flux penetrations. 相似文献
32.
A. Nakajima Y. Masuda E. Matsuda Y. Ueda H. Sameshima T. Ikenoue 《Applied magnetic resonance》2011,40(4):535-544
The reaction between 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl (PCAM), which is a blood–brain-barrier (BBB)
permeable stable cyclic nitroxide, and ascorbic acid was examined in a low dissolved oxygen-phosphate buffer (low DO-PB, 0.1 mM
DO) under 8% oxygen in a glove bag or in an ordinal dissolved oxygen-phosphate buffer (ordinal DO-PB, 0.3 mM DO) under 21%
oxygen in an open atmosphere with and without diethylenetriaminepentaacetic acid (DTPA). In PB with DTPA, no difference was
observed between the results in the low DO-PB and those in the ordinal DO-PB. In the ordinal DO-PB without DTPA, the rate
constant of the PCAM decrease was half that in the low DO-PB without DTPA. The present results indicate that high DO and coexisting
transition metal ions caused the oxidation of ascorbic acid, which degraded the PCAM reduction. The stable nitroxide-ascorbic
acid system without DTPA was found to be applicable to an in vitro model for the acute hypoxia ischemia. 相似文献
33.
Visible‐Light‐Mediated Addition of α‐Aminoalkyl Radicals to [60]Fullerene by Using Photoredox Catalysts 下载免费PDF全文
Dr. Yoshihiro Miyake Yuya Ashida Dr. Kazunari Nakajima Prof. Dr. Yoshiaki Nishibayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(20):6120-6125
The functionalization of fullerene has been extensively studied and various fullerene derivatives have been synthesized. We have succeeded in the functionalization of [60]fullerene by using α‐aminoalkyl radicals generated by visible‐light‐mediated single‐electron oxidation of α‐silylamines as synthetic intermediates. In these reactions, the introduction of diarylamino groups, which are useful electron donors, has been easily achieved. 相似文献
34.
Tasuku Nakajima Hidemitsu Furukawa Yoshimi Tanaka Takayuki Kurokawa Jian Ping Gong 《Journal of Polymer Science.Polymer Physics》2011,49(17):1246-1254
Introduction of soft filler in a hard body, which is one of the common toughening methods of hard polymeric materials, was applied for further toughening of robust double network (DN) hydrogels composed of poly(2‐acrylamido‐2‐methylpropanesulfonic acid) gels (PAMPS gels) as the first component and polyacrylamide (PAAm) as the second component. The fracture energy of the DN gels with the void structure (called void‐DN gels) became twice when the volume fraction of void was 1–3 vol % and the void diameter was much larger than the Flory radius of the PAAm chains. Such toughening was induced by wider range of internal fracture of the PAMPS network derived from partial stress concentration near void structure. Considering the mechanical tests and the dynamic light scattering results, it is implied that the absence of the load‐bearing PAAm structure inside the void is important for the toughening. © 2011 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 49: 1246–1254, 2011 相似文献
35.
Masahito Segi Hiroaki Yamamoto Takeyoshi Hori Tadashi Nakajima 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):599-602
Selenoaldehydes and selenoketones, generated by thermal retro-Diels-Alder reaction of their cycloadducts with cyclopentadiene, reacted with oxygen-functionalized conjugated dienes such as 1-acetoxy-1,3-butadiene, Danishefsky's diene, and 1,4-diacetoxy-1,3-butadiene to give the corresponding cycloadducts in good yields regioselectively. 相似文献
36.
Tsuyoshi Satoh Takayuki Kuramoto Shingo Ogata Hiroyuki Watanabe Takahito Saitou Makoto Tadokoro 《Tetrahedron: Asymmetry》2010,21(1):1-5
Treatment of enantiomerically pure 1-chlorovinyl p-tolyl sulfoxides, derived from cyclic ketones and (R)-chloromethyl p-tolyl sulfoxide, with the lithium enolate of tert-butyl carboxylates gave adducts in quantitative yields as single diastereomers. The adducts were treated with i-PrMgCl in toluene to afford optically active bicyclo[n.1.0]alkanes bearing a tert-butyl carboxylate moiety in up to 99% enantiomeric excess through the enantioselective 1,3-CH insertion reaction of the generated chiral magnesium carbenoids. This is the first example of the enantioselective 1,3-CH insertion reaction of magnesium carbenoid. 相似文献
37.
Naoto Nishio Kentaro Yamana Yasutaka Yamaguchi Takehiko Inaba Koji Kuroda Tadashi Nakajima Kouhei Ohno Hideo Fujimura 《国际流体数值方法杂志》2010,63(12):1435-1447
In this study, the whole process of liquid droplet impact onto a liquid surface up to the consequent formation of the central column was simulated using the smoothed particle hydrodynamics method (SPH), and compared with an experiment using a high‐speed video camera. The surface tension tensor for the particle‐based expression was adequately included as the gradient of the surface tension and that enabled the simulation leading to the formations of crater and crown as well as the consequent central column. The simulated time series of the crater depth and diameter and crown height corresponded quantitatively well with the experimental result up to the rebound motion while discrepancies remained as a lower central column height in the simulation, and this seemed to be ascribed to the difficulty in realizing the complex surface structure that inevitably appeared in the fast rebound motion. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
38.
The nano-palpation technique,i.e.,nanometer-scale elastic and viscoelastic measurements based on atomic force microscope,is introduced.It is demonstrated to be very useful in analyzing nanometer-scale materials properties for the surfaces and interfaces of various types of soft materials.It enables us to obtain not only structural information but also mechanical information about a material at the same place and at the same time. 相似文献
39.
We revisited the vanadium oxide phosphors, AVO3 (A:K, Rb, and Cs) and M3V2O8 (A:Mg and Zn) for a revaluation of possibility of these compounds for lighting applications, and the internal quantum efficiency (η) and luminescent colour properties for AVO3 (A:K, Rb, and Cs) and M3V2O8 (A:Mg, and Zn) have been presented. The AVO3 showed the broadband emission from 380 to 800 nm, and the η for the KVO3, RbVO3 and CsVO3 were 4%, 79% and 87%, respectively. The CIE colour coordinates are located at white region on the chromaticity diagram. The M3V2O8 (A:Mg and Zn) also exhibited a quite broadband emission between 410 and 900 nm, indicating yellow luminescent colour. The Zn3V2O8 showed high η value, 52%, compared to that of the Mg3V2O8 (η=6%). This enhancement of η in the Zn3V2O8 could be due to the increasing exciton diffusion assisted by the hybridizations of Zn 3d and O 2p orbitals for the valence band, and Zn 4s and Ti 3d orbitals for the conduction band. 相似文献
40.