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151.
Patrizio Angelini William Evans Fabrizio Frati Joachim Gudmundsson 《Journal of Graph Theory》2016,82(1):45-64
We show that every n‐vertex planar graph admits a simultaneous embedding without mapping and with fixed edges with any ‐vertex planar graph. In order to achieve this result, we prove that every n‐vertex plane graph has an induced outerplane subgraph containing at least vertices. Also, we show that every n‐vertex planar graph and every n‐vertex planar partial 3‐tree admit a simultaneous embedding without mapping and with fixed edges. 相似文献
152.
Concomitant Carboxylate and Oxalate Formation From the Activation of CO2 by a Thorium(III) Complex 下载免费PDF全文
Alasdair Formanuik Dr. Fabrizio Ortu Christopher J. Inman Dr. Andrew Kerridge Dr. Ludovic Castro Prof. Laurent Maron Dr. David P. Mills 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(50):17976-17979
Improving our comprehension of diverse CO2 activation pathways is of vital importance for the widespread future utilization of this abundant greenhouse gas. CO2 activation by uranium(III) complexes is now relatively well understood, with oxo/carbonate formation predominating as CO2 is readily reduced to CO, but isolated thorium(III) CO2 activation is unprecedented. We show that the thorium(III) complex, [Th(Cp′′)3] ( 1 , Cp′′={C5H3(SiMe3)2‐1,3}), reacts with CO2 to give the mixed oxalate‐carboxylate thorium(IV) complex [{Th(Cp′′)2[κ2‐O2C{C5H3‐3,3′‐(SiMe3)2}]}2(μ‐κ2:κ2‐C2O4)] ( 3 ). The concomitant formation of oxalate and carboxylate is unique for CO2 activation, as in previous examples either reduction or insertion is favored to yield a single product. Therefore, thorium(III) CO2 activation can differ from better understood uranium(III) chemistry. 相似文献
153.
Fabrizio Colombo Roman Lávička Irene Sabadini Vladimír Souček 《Mathematical Methods in the Applied Sciences》2016,39(3):412-424
In this paper, we introduce some integral transforms that map slice monogenic functions to monogenic functions. We then show that one of these integral transforms, which is based on the Cauchy formula of slice monogenic functions, is useful to define a functional calculus depending on a parameter for n‐tuples of bounded operators. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
154.
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156.
We report the first-principle calculation and analysis of the vibrationally resolved steady-state absorption and fluorescence spectra, and of the zero-time fluorescence spectrum of a sizable molecule, coumarin C153, in two different solvents. Our approach, bringing together the most recent developments in the fields of time-dependent density functional theory and of polarizable continuum solvent models, with an efficient method for the computation of vibrational contributions to transition intensities, allows a remarkable agreement with experiments, both concerning the line shapes and the solvatochromic and Stokes shifts. The method is also able to nicely describe the solvent relaxation effect on the fluorescence spectra, perfectly reproducing the energy shift between zero-time and steady-state fluorescence. 相似文献
157.
Altland K Benson MD Costello CE Ferlini A Hazenberg BP Hund E Kristen AV Linke RP Merlini G Salvi F Saraiva MJ Singer R Skinner M Winter P 《Electrophoresis》2007,28(12):2053-2064
Mutations of the human transthyretin (TTR) gene have attracted medical interest as a cause of amyloidosis. Recently, we have described in detail an electrophoretic procedure with PAGE followed by IEF in urea gradients for the study of the microheterogeneity of TTR monomers (Altland, K., Winter, P., Sauerborn, M. K., Electrophoresis 1999, 20, 1349-1364). In this paper, we present a study on 49 different mutations of TTR including 33 that result in electrically neutral amino acid substitutions. The aims of the investigation were to test the sensitivity of the procedure to detect TTR variants in patients with TTR amyloidosis and their relatives and to identify some common characteristics that could explain the amyloidogenicity of these variants. We found that all tested amyloidogenic mutations could be detected by our method with the exception of those for which the corresponding variant was absent in plasma samples. Most of the electrically neutral amyloidogenic TTR variants had in common a reduced conformational stability of monomers by the activity of protons and urea. For three variants, e.g. TTR-F64L, TTR-I107V and TTR-V122I, the monomers had a conformational stability close to that of normal monomers but we found experimental and structural arguments for a weakening of the monomer-monomer contact. All types of amyloidogenic mutations affected the stability of TTR tetramers. 相似文献
158.
Mazzeo P Di Pasquale D Ruggieri F Fanelli M D'Archivio AA Carlucci G 《Biomedical chromatography : BMC》2007,21(11):1166-1171
A high-performance liquid chromatographic method for the simultaneous determination of di(2-ethylhexyl)phthalate (DEHP) and its major metabolite mono(2-ethylhexyl)phthalate (MEHP) in seminal plasma was developed and validated. The method involves liquid-liquid extraction followed by isocratic reversed-phase chromatography with diode-array detection. The recovery, selectivity, linearity, precision and accuracy of the method were evaluated from the analysis of spiked seminal plasma samples. The effect of mobile-phase composition and pH on the retention of the target analytes was investigated. The limits of detection were 0.010 and 0.015 microg/mL, for DEHP and MEHP, respectively. This method was used to analyze real samples in support of clinical studies on these potential endocrine disruptors. 相似文献
159.
In the recent paper [Adv. Applied Math., 38 (2007), 210–226] it is proved that the special matchings of permutations generate
a Coxeter group. In this paper we generalize this result to a class of Coxeter groups which includes many Weyl and affine
Weyl groups. Our proofs are simpler, and shorter, than those in [loc. cit.]
All authors are partially supported by EU grant HPRN-CT-2001-00272.
Received: 30 October 2006 相似文献
160.
Sicilia F Blancafort L Bearpark MJ Robb MA 《The journal of physical chemistry. A》2007,111(11):2182-2192
In this paper, we present a practical approach for the characterization of critical points on conical intersection seams as either local minima or saddle points using second-derivative technology. The utility of this methodology is illustrated by the analysis of seven S0/S1 (2Ag/1Ag) conical intersection points involved in the photochemistry of butadiene. The characterization of critical points on the crossing seam requires second derivatives computed in curvilinear coordinates. Using such coordinates, we can represent the branching space and the intersection space to second order. Although these curvilinear coordinates are conceptually important, they also give rise to two additional practical applications. First, such coordinates yield information on the nature of vibrational modes that are stimulated following radiationless decay at a crossing point. Second, the second-order force field is directly comparable to experimental spectroscopic data for Jahn-Teller systems. We will illustrate the latter idea for the cyclopentadienyl radical. 相似文献