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11.
The classical Voigt functions occur frequently in a wide variety of problems in astrophysical spectroscopy, emission, absorption
and transfer of radiation in heated atmosphere, and plasma dispersion, and indeed also in the theory of neutron reactions.
Here, in the present paper, by applying several known upper bounds for the first-kind Bessel function J
ν
(x) given recently by (for example) Landau, Olenko and Krasikov, sharp bounding inequalities are obtained for the unified multivariable
Voigt function V
μ,ν
(x; y) in terms of the confluent Fox-Wright function 1ψ0 and its incomplete variant 1ψ0. Connections of the unified multivariable Voigt function V
μ,ν
(x; y) with other unifications and generalizations of the classical Voigt function are also briefly pointed out. 相似文献
12.
Praveen K. Tandon Gayatri Sumita Sahgal Manish Srivastava Santosh B. Singh 《应用有机金属化学》2007,21(3):135-138
Catalytic activities of three transition metals, as iridium (III) chloride, rhodium (III) chloride and palladium (II) chloride, were compared in the oxidation of six aromatic aldehydes (benzaldehyde, p‐chloro benzaldehyde, p‐nitro benzaldehyde, m‐nitro benzaldehyde, p‐methoxy benzaldehyde and cinnamaldehyde), two hydrocarbons (viz. (anthracene and phenanthrene)) and one aromatic and one cyclic alcohol (cyclohexanol and benzyl alcohol) by 50% H2O2. The presence of traces (substrate: catalyst ratio equal to 1:62500 to 1:1961) of the chlorides of iridium(III), rhodium(III) and palladium(II) catalyze these oxidations, resulting in good to excellent yields. It was observed that in most of the cases palladium(II) chloride is the most efficient catalyst. Conditions for the highest and most economical yields were obtained. Deviation from the optimum conditions decreases the yields. Oxidation in aromatic aldehydes is selective at the aldehydeic group only and other groups remain unaffected. This new, simple and economical method, which is environmentally safe, also requires less time. Reactive species of catalysts, existing in the reaction mixture are also discussed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
13.
Satya Prakash 《Pramana》1989,33(1):109-131
This article summarizes the recent radiochemical investigations on mass, charge kinetic energy and fragment angular distributions
in low energy fission of actinides. 相似文献
14.
Summary Some simple ideas are used here to prove a theorem on generating functions for a certain class of q-polynomials. This general theorem is then applied to derive a fairly large number of known as well as new generating functions for the familiar q-analogues of various polynomial systems including, for example, the classical orthogonal polynomials of Hermite, Jacobi, and Laguerre. A number of other interesting consequences of the theorem are also discussed. 相似文献
15.
Over the last two decades many strategies have been planned to design specific drugs for rare diseases to target their action
at the DNA level. Advancements in our understanding of the interactions of small nonpeptide molecules with DNA have opened
the doors for “rational” drug design. Special methods have now been developed to give accurate account of the precise location
of ligand-DNA adducts on target DNA. We are now in a position to think of designing ligands that recognize particular sequences
of base pairs. This work will allow us to enter into a new era of gene therapy for diseases like Cystic fibrosis, Alzheimer’s
disease and many related disorders at genetic level. These ligands can also be employed in the treatment of various types
of cancers. They may also be useful as highly specific probes to locate particular sequences in the genomic DNA. 相似文献
16.
17.
Homopolymerization of methyl methacrylate (MMA) was carried out in the presence of triphenylstibonium 1,2,3,4-tetraphenyl-cyclopentadienylide
as an initiator in dioxane at 65°C±0·l°C. The system follows non-ideal radical kinetics (R
p
∝ [M]1·4 [I]0·44
@#@) due to primary radical termination as well as degradative chain-transfer reaction. The overall activation energy and average
value ofk
2
p
/k
t
were 64 kJmol−1 and 0.173 × 10−3 1 mol−1 s−1 respectively 相似文献
18.
It has been found that the states of the 2-charge extremal D1–D5 system are given by smooth geometries that have no singularity and no horizon individually, but a ‘horizon’ does arise after ‘coarse-graining’. To see how this concept extends to the 3-charge extremal system, we construct a perturbation on the D1–D5 geometry that carries one unit of momentum charge P. The perturbation is found to be regular everywhere and normalizable, so we conclude that at least this state of the 3-charge system behaves like the 2-charge states. The solution is constructed by matching (to several orders) solutions in the inner and outer regions of the geometry. We conjecture the general form of ‘hair’ expected for the 3-charge system, and the nature of the interior of black holes in general. 相似文献
19.
Themaximal minor polytope Π
m, n
is the Newton polytope of the product of all maximal minors of anm×n matrix of indeterminates. The family of polytopes {Π
m, n
} interpolates between the symmetric transportation polytope (form=n−1) and the permutohedron (form=2). Both transportation polytope and the permutohedron aresimple polytopes but in general Π
m, n
is not simple. The main result of this paper is an explicit construction of a class of simple vertices of Π
m, n
for generalm andn. We call themvertices of diagonal type. For every such vertexv we explicitly describe all the edges and facets of Π
m, n
which containv. Simple vertices of Π
m, n
have an interesting algebro-geometric application: they correspond tononsingular extreme toric degenerations of the determinantal variety ofm×n matrices not of full rank.
Andrei Zelevinsky was partially supported by the NSF under Grant DMS-9104867. 相似文献
20.