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121.
Yoshio Hoei Masaru Okabe Kazuo Yamaura Shuji Matsuzawa 《Journal of polymer science. Part A, Polymer chemistry》1996,34(13):2775-2782
A characterization for crystalline junction polymer gels has been extended by introducing a new parameter which implies a measure of the number of the polymer molecules passing through the crystallizing junctions. The parameter has been considered in a theoretical gel melting relation derived by Takahashi, Nakamura, and Kagawa and a crystallite size distribution has also been considered. The equation obtained was examined on ethylene–propylene copolymer gels by using the previous data of melting temperatures determined from DSC, crystallite sizes from x-ray and DSC measurements, and reaction probabilities from 13C-NMR measurements. Consequently, the parameter was found to be helpful as one additional measure. Also, it was confirmed that the average crystallite sizes estimated in several different ways were all in good agreement with the conventional data. © 1996 John Wiley & Sons, Inc. 相似文献
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Hiroshi Kobayashi Youkoh Kaizu Hitoshi Kimura Hideyo Matsuzawa Hirohiko Adachi 《Molecular physics》2013,111(6):1009-1030
The DV-Xα molecular-orbital calculations have been carried out on [Crbpy(CO)4](bpy,2,2′-bipyridine) and its electron attachment and detachment products. The one-electron attachment of [Crbpy(CO)4] yields a complex of bipyridine anion radical, while the one-electron detachment results in ionization of the central metal atom. The lowest excited state of [Crbpy(CO)4] is the metal-to-ligand charge-transfer (MLCT) excited state which consists of the bipyridine anion radical and the central metal ionized. The transition-state calculation predicts the lowest MLCT excited states at around 23~30×103 cm?1 and the lowest bipyridine (π,π*) excitations at 36×103 cm?1 and 42~45×103 cm?1. The calculation also concludes that the MLCT excitation induces a counter migration of the other electrons not directly involved in the charge-transfer excitation. The configuration-interaction calculations predict the lowest MLCT excited singlet states at around 21~35×103 cm?1 and the lowest bipyridine (π, π*) excited singlet states at 42~62×103 cm?1, while the emissive lowest MLCT triplet state is at 17×103 cm?1. The transition moments evaluated with the transition-state wavefunctions can reproduce qualitatively the observed absorption spectral profile. The intensity of the MLCT transitions is obtained from the allowed (π, π*) transitions of coordinated bipyridine but is not due to the intrinsic transition moments of MLCT excitations. 相似文献
124.
F. Nannelli V. S. U. Fazio Y. Matsuzawa L. Komitov K. Ichimura 《Molecular Crystals and Liquid Crystals》2013,570(1):621-630
Abstract Many nematic liquid crystals (NLCs) lack a polar headgroup and thus are not able to form stable monolayers at the air/water (a/w) interface. A way to obtain monomolecular films of these compounds is to incorporate them into host monolayers of amphiphilic molecules. We report a comparative investigation of mixed films of Calix[4]resorcinarene O-octacarboxymethylated (CRO) with the non-amphiphilic NLC MBBA and with the amphiphilic stearic acid (SA). The comparative study is useful for a better understanding of the characteristics of the CRO-MBBA mixed films. Surface-pressure and surface-potential measurements on the monolayers at a/w interface, as well as ellipsometric and spectroscopic measurements on transferred Langmuir-Blodgett (LB) films, confirm that MBBA is additively incorporated into CRO films. 相似文献
125.
A chiral tetrathiafulvalene (TTF) dimer bridged by an allene framework (1) was synthesized. An X-ray analysis of 1 revealed an effective conjugation between TTF and the allene backbone. Allene 1 was resolved into both enantiomers, which showed strong chiroptical electrochromic properties. Absolute configuration of the allene was validated by theoretical study of the electronic circular dichroism (ECD) spectrum. ECD spectra of cationic species 1(2+) and 1(4+) exhibited intense Cotton Effects over the visible region. 相似文献
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127.
Moser DF Naka A Guzei IA Müller T West R 《Journal of the American Chemical Society》2005,127(42):14730-14738
Reactions of stable silylenes 1 and 2 with a variety of halogenated organic compounds have been studied. Depending on the nature of the halocarbon, the products can be disilanes, LSiX-LSiR, or monosilanes, LSiXR, or a mixture of both types of products. Hexachloroethane reacts with the silylenes to give mainly the dichlorodisilane, LSiX-LSiX. The experimental results are rationalized in terms of several related free-radical chain mechanisms. 相似文献
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Mayumi Chida Satoru Takahashi Ryunosuke Konishi Dr. Takeshi Matsumoto Dr. Akinobu Nakada Dr. Masanori Wakizaka Dr. Wataru Kosaka Prof. Hitoshi Miyasaka Prof. Ho-Chol Chang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(66):16354-16366
The combination of a cobalt-dioxolene core that exhibits valence tautomerism (VT) with pyridine-3,5-dicarboxylic acid functionalized with chains bearing two, four, or six oxyethylene units led to new complexes ConEGEspy (n = 2, 4, and 6). These complexes commonly form violet crystals of the low-spin (ls)-[CoIII(nEGEspy)2(3,6-DTBSQ)(3,6-DTBCat)] (ls-[CoIII], 3,6-DTBSQ = 3,6-di-tert-butyl semiquinonato, 3,6-DTBCat = 3,6-di-tert-butyl catecholato). Interestingly, violet crystals of Co2EGEspy in the ls-[CoIII] transitioned into a green liquid, accompanied by an almost complete VT shift (94 %) to the high-spin (hs)-[CoII(nEGEspy)2(3,6-DTBSQ)2] (hs-[CoII]) upon melting. In contrast, violet crystals of Co4EGEspy and Co6EGEspy in the ls-[CoIII] exhibited partial VT (33 %) and only a 9.3 % VT shift after melting, respectively. These data demonstrate the tunability of the synchronicity of the molecular VT and macroscopic solid-liquid transitions by optimizing the tethered chains, thus establishing a new strategy for coupling bistable molecules with the macroscopic world. 相似文献