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排序方式: 共有193条查询结果,搜索用时 31 毫秒
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In this paper, we propose an algorithm which computes the correlated equilibrium with global-optimal (i.e., maximum) expected social welfare for single stage polynomial games. We first derive tractable primal/dual semidefinite programming (SDP) relaxations for an infinite-dimensional formulation of correlated equilibria. We give an asymptotic convergence proof, which ensures solving the sequence of relaxations leads to solutions that converge to the correlated equilibrium with the highest expected social welfare. Finally, we give a dedicated sequential SDP algorithm and demonstrate it in a wireless application with numerical results.  相似文献   
66.
α,β-Unsaturated acetylenic γ-hydroxyketones have been shown to react with ethyl acetoacetate in a Michael-addition fashion and subsequently undergo cyclization followed by dehydration to give substituted furans with a predictable regiospecificity. The yields were good to excellent. A mechanism for the transformation is proposed, and this mechanism explains why furan formation does not take place when the same unsaturated ketones are treated with α-methylated acetoacetate and diethyl malonate.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource: Full experimental and spectral details.]  相似文献   
67.
It is widely believed that, in contrast to its electron-doped counterparts, the hole-doped compound Ba(1-x)K(x)Fe(2)As(2) exhibits a mesoscopic phase separation of magnetism and superconductivity in the underdoped region of the phase diagram. Here, we report a combined high-resolution x-ray powder diffraction and volume-sensitive muon spin rotation study of Ba(1-x)K(x)Fe(2)As(2) showing that this paradigm does not hold true in the underdoped region of the phase diagram (0≤x≤0.25). Instead we find a microscopic coexistence of the two forms of order. A competition of magnetism and superconductivity is evident from a significant reduction of the magnetic moment and a concomitant decrease of the magnetoelastically coupled orthorhombic lattice distortion below the superconducting phase transition.  相似文献   
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The closing of the nuclear fuel cycle is an unsolved problem of great importance. Separating radionuclides produced in a nuclear reactor is useful both for the storage of nuclear waste and for recycling of nuclear fuel. These separations can be performed by designing appropriate chelation chemistries and liquid-liquid extraction schemes, such as in the TALSPEAK process (Trivalent Actinide-Lanthanide Separation by Phosphorus reagent Extraction from Aqueous Komplexes). However, there are no approved methods for the industrial scale reprocessing of civilian nuclear fuel in the United States. One bottleneck in the design of next-generation solvent extraction-based nuclear fuel reprocessing schemes is a lack of interfacial mass transfer rate constants obtained under well-controlled conditions for lanthanide and actinide ligand complexes; such rate constants are a prerequisite for mechanistic understanding of the extraction chemistries involved and are of great assistance in the design of new chemistries. In addition, rate constants obtained under conditions of known interfacial area have immediate, practical utility in models required for the scaling-up of laboratory-scale demonstrations to industrial-scale solutions. Existing experimental techniques for determining these rate constants suffer from two key drawbacks: either slow mixing or unknown interfacial area. The volume of waste produced by traditional methods is an additional, practical concern in experiments involving radioactive elements, both from disposal cost and experimenter safety standpoints. In this paper, we test a plug-based microfluidic system that uses flowing plugs (droplets) in microfluidic channels to determine absolute interfacial mass transfer rate constants under conditions of both rapid mixing and controlled interfacial area. We utilize this system to determine, for the first time, the rate constants for interfacial transfer of all lanthanides, minus promethium, plus yttrium, under TALSPEAK process conditions, as a first step toward testing the molecular mechanism of this separation process.  相似文献   
69.
The present work introduces the determination of fluoroquinolone antibiotics (FQs) in aqueous solutions through the fluorescent response of Eu(TTA)3 and [Eu(TTA)31] (TTA and 1 are thenoyltrifluoroacetonate and phosphine oxide derivative) complexes encapsulated into the polyelectrolyte capsules fabricated through layer-by-layer deposition of poly(sodium 4-styrenesulfonate) (PSS) and polyethyleneimine (PEI). The variation of luminescent core, polyelectrolyte deposition and concentration conditions reveals two modes of fluorescent response on FQs of diverse structure namely the sensitization and quenching of Eu(III) centered luminescence. The obtained regularities reveal the ternary complex formation and the ligand exchange occurring at the interface of polyelectrolyte coated [Eu(TTA)31] based colloids as the reasons of the diverse fluorescent response of Eu(III) centered luminescence on FQs. The factors affecting the fluorescent response have been revealed, which are: the content of luminescent core, the mode of polyelectrolyte deposition, concentration and structure of FQs. The discrimination of moxifloxacin and lomefloxacin from levofloxacin, ofloxacin, difloxacin, perfloxacin through the quenching of Eu(III) luminescence in PSS-[Eu(TTA)31] colloids has been revealed.  相似文献   
70.
In this paper we consider boundary-value problems in domains with perforated boundaries. We use the classification of homogenized (limit) problems depending on the ratio of small parameters, which characterize the diameter of the holes and the distance between them. We study the analogue of the Helmholtz resonator for domains with a perforated boundary.  相似文献   
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