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1.
Cyclic Markov equilibria in stochastic games 总被引:1,自引:0,他引:1
We examine a three-person stochastic game where the only existing equilibria consist of cyclic Markov strategies. Unlike in two-person games of a similar type, stationary ε-equilibria (ε > 0) do not exist for this game. Besides we characterize the set of feasible equilibrium rewards. 相似文献
2.
3.
An expression for the heat conductivity
xx
is derived in the effective medium approximation. Mott type formulas are obtained for
xx
and the Peltier coefficient
xx
. Using percolation theory in a three-dimensional system the Wiedemann-Franz ratio was found to depend on the temperature like
. The Mott type formulas were evaluated in a similar way for a two-dimensional system in the quantum Hall regime within the high-field percolation model. In contrast to previous calculations of the high field hopping conductivity
xx
, the results are fully consistent with the experimental data on
xx
and the density of states at the Fermi level. Finally,
xx
is estimated which together with
xx
and
xy
=ie
2/h(i=0,1,2,...), determines both thermopower coefficients
xx
and
xy
.Dedicated to Professor W. Brenig on the occasion of his 60th birthday 相似文献
4.
Vladimir Kovacik Janos Hirsch Detlef Thlmann Hans-Friedrich Grützmacher 《Journal of mass spectrometry : JMS》1991,26(12):1085-1088
Glycosidic oxocarbenium ions A1+ were formed by isobutane chemical ionization from methyl 2,3,4,6-tetra-O-methyl-β-D -mannopyranoside, methyl 2,3,4,6-tetra-0-methyl-β-D -galactopyranoside and methyl 2,3,4,6-tetra-O-methyl-β-D -glucopyranoside (the ring - O-being converted into ? O ? ), and then- reaction with ammonia was studied by Fourier transform ion cyclotron resonance Spectrometry. Very slow formation (reaction efficiency 0.6-1.4%) of the adduct ion [A1 + NH3]4 was observed as the main process for carefully thermalized ions A1+. Interestingly, the efficiency of the adduct ion formation depends on the sterochemistry of ions A1+. 相似文献
5.
A facile and efficient stereospecific route to the enzyme-inhibitory 2-amide analogs of phosphatidycholine is reported. 相似文献
6.
Nanosensors based on responsive polymer brushes and gold nanoparticle enhanced transmission surface plasmon resonance spectroscopy 总被引:4,自引:0,他引:4
Tokareva I Minko S Fendler JH Hutter E 《Journal of the American Chemical Society》2004,126(49):15950-15951
Swelling (and shrinking) of poly(2-vinylpyridine), P2VP, polymer brushes, caused by pH changes, could be readily monitored by transmission surface plasmon resonance, T-SPR, spectroscopy. Gold nanoparticles attached to the P2VP polymer brushes dramatically enhanced the pH-induced shift in the T-SPR absorption spectra. (A 50 nm shift of the absorption maximum of the T-SPR spectrum of the supporting gold nanoislands was observed upon changing the pH from 5.0 to 2.0, corresponding to a swelling of the polymer brushes from 8.1 +/- 0.7 to 24.0 +/- 2.0 nm. Same shift in the opposite direction was observed upon changing the pH from 2.0 to 5.0.) 相似文献
7.
8.
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
9.
10.
When dissolved in trifluoroacetic or fluorosulfonic acid, 6-methylene-tricyclo[3.2.1.02,7]oct-3-ene-8-one derivatives of type 2 (;scheme 1); give polymethyltropylium salts in moderate to good yields by CO-extrusion. These tropylium salts can be isolated pure as hexachloroplatinates. Thus the tricyclic compound 6 gives 1,2,4-trimethyltropylium trifluoroacetate 19 in trifluoroacetic acid (;scheme 3);. This salt in CDCl3 is in equilibrium with its covalent cycloheptatriene (;tropilidene); form 20 , the ratio of the two forms being 1.5–2.1/1. The tropylium salt 19 is reduced by lithium aluminium hydride to a mixture of 1,2,4-trimethylcycloheptatrienes, isomeric with respect to the double bonds, which on hydride abstraction with trityl-tetrafluoroborate gives again the 1,2,4-trimethyltropylium salt 19 (;scheme 3);. From the trimethyl-substituted tricyclic compounds 7 and 8 , in trifluoroacetic acid, are obtained respectively the 1,2,4,6- and 1,2,3,4-tetramethyltropylium ions (; 22 and 24 ); (;schemes 4 and 5);. In this way the 1,2,3,5,6-pentamethyl-tropylium ion (; 26 ); was obtained from 9 (;scheme 6);. With the higher substituted tropylium trifluoroacetates in CDCl3 the equilibrium tropylium trifluoroacetate ? trifluoroacetoxycycloheptatrienes lies well to the left. The hexamethylated tricyclic compound 10 gives a small quantity of heptamethyltropylium trifluoroacetate (; 27 ); and as the main product the C(;3);-protonated species 28 (;scheme 7);, which when treated with aqueous sodium hydrogencarbonate yielded unchanged educt 10 . - The heptamethyltropylium ion (; 27 ); was, apart from polymeric species, the only product from the treatment of starting material 10 with fluorosulfonic acid (;50%);; its salts have as yet not been isolated in their pure form, however. The mechanism for the rearrangement of the tricyclic compounds of type 2 into tropylium salts is presented for compound 6 in scheme 8: The first step is the protonation at C(;9);. Ring opening of the cyclopropane of the tertiary carbenium ion 29 gives the allylic ion 30 , which then yields the aromatic tropylium salt 19 by carbon monoxide extrusion in a linear cheletropic reaction. The smooth conversion with strong acids of the easily accessible tricyclic compounds of type 2 to the corresponding polymethylated tropylium salts, presents a new and useful method for the synthesis of the latter compounds. 相似文献