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31.
The main purpose of this paper is to introduce and investigate a new class of generalized Apostol–Bernoulli polynomials based on a definition given by Natalini and Bernardini (2003) [22] for the generalized Bernoulli polynomials. We obtain a generalization of the Srivastava–Pintér addition theorem (Srivastava and Pintér (2004) [23]). We also give a list of expressions involving special functions that could be used to obtain some analogues of the Srivastava–Pintér addition theorem. Finally, we give an analogue featuring the new class of generalized Apostol–Bernoulli polynomials. 相似文献
32.
The evaluation of on-line intelligent transportation system (ITS) measures, such as adaptive route-guidance and traffic management systems, depends heavily on the use of faster than real time traffic simulation models. Off-line applications, such as the testing of ITS strategies and planning studies, are also best served by fast-running traffic models due to the repetitive or iterative nature of such investigations. This paper describes a simulation-based, iterative dynamic equilibrium traffic assignment model. The determination of time-dependent path flows is modeled as a master problem that is solved using the method of successive averages (MSA). The determination of path travel times for a given set of path flows is the network-loading sub-problem, which is solved using the space-time queuing approach of Mahut. This loading method has been shown to provide reasonably accurate results with very little computational effort. The model was applied to the Stockholm road network, which consists of 2100 links, 1191 nodes, 228 zones, representing and 4964 turns. The results show that this model is applicable to medium-size networks with a very reasonable computation time. 相似文献
33.
Deanna De Marcano Bernardo Mndez Jeannette De Mndez Jos Monasterios Aníbal C. Rojas Thomas G. Halsall 《Magnetic resonance in chemistry : MRC》1983,21(8):524-525
The 13C NMR spectra of a series of some Δ4(20),11-taxadiene derivatives are reported. A detailed analysis of their assignments is presented. 相似文献
34.
Deanna Marcano Jeannette De Mndez Ana C. Ortiz Mirna Salinas 《Magnetic resonance in chemistry : MRC》1984,22(11):736-738
The 13C chemical shift data of several D-homoandrostanes with heteroatoms (N,O) in the 17a-position are reported. Heteroatom effects on the shieldings of the carbons of rings C and D are discussed. 相似文献
35.
G. Perrault M. Tremblay M. Bédard G. Duchesne R. Voyzelle 《European Polymer Journal》1974,10(2):143-148
The molecular probe technique has been shown to be useful for measuring the glass transition temperature of a highly-filled composite, or of a polybutadiene prepolymer covering surfaces of varying types. The measured Tg of 193°K is independent of the curing stage as well as of the nature of functional groups. Transitions between 349 and 364°K were detected in a Fe2O3-containing composite, showing the general applicability of the technique. Studies of the slope of the curve relating the logarithm of the specific retention volume to the reciprocal of the absolute temperature can lead to useful information concerning the orientation of the polybutadiene prepolymer at the polymer-solid interface. 相似文献
36.
37.
Slater JW D'Alessandro DM Keene FR Steel PJ 《Dalton transactions (Cambridge, England : 2003)》2006,(16):1954-1962
The dinuclear bis(2,2'-bipyridine)ruthenium complex of 4,5-di(2-pyridyl)imidazolate has been prepared and separated into its (meso and rac) diastereoisomers. The 2-phenyl substituted analogue forms the meso isomer selectively. All three complexes have been characterised by 1H NMR and X-ray crystallography. Electrochemical measurements and spectroelectrochemistry of the mixed-valence states reveal strong metal-metal interactions and IVCT bands that are highly dependent on the electrolyte. 相似文献
38.
Bautista DL Morris DH Stein L Asher W Hammitt T 《Journal of chemical information and modeling》2006,46(1):334-344
In this study, we have developed a two receptor model system to describe the R and R states of G-protein coupled receptors, specifically the alpha(1D) adrenergic receptor. The two models interact with agonist (epinephrine) and antagonist (BMY7378) differently. The active model has increased interactions with epinephrine. The inactive model has increased interactions with BMY7378. We also explored the protonation state of the ligands. When the most basic amine was protonated, we found increased hydrogen bonding and increased aromatic interactions. Protonated epinephrine hydrogen bonds with Asp176 and has aromatic residues Trp172, Trp235, Trp361, and Phe388 within 3 Angstroms. Protonated BMY7378 hydrogen bonds with Trp172 and Lys236 and has aromatic residues Trp172, Trp254, Phe364, Phe384, and Phe388 within 3 Angstroms. We conclude that the two model system is required to represent the two states of the receptor and that protonation of the ligand is also critical. 相似文献
39.
[reaction: see text] The absolute configuration of methyl lactobacillate and its 9,10 homologue, both isolated from Escherichia coli B-ATCC 11303, was found to be 11R,12S and 9R,10S, respectively. 相似文献
40.
We study the Mott transition, antiferromagnetism, and superconductivity in layered organic conductors using the cellular dynamical mean-field theory for the frustrated Hubbard model. A d-wave superconducting phase appears between an antiferromagnetic insulator and a metal for t'/t=0.3-0.7 or between a nonmagnetic Mott insulator (spin liquid) and a metal for t'/t>or=0.8, in agreement with experiments on layered organic conductors including kappa-(ET)2Cu2(CN)3. These phases are separated by a strong first-order transition. The phase diagram gives much insight into the mechanism for -wave superconductivity. Two predictions are made. 相似文献