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121.
Yuval Ne’eman 《Acta Physica Hungarica A》2004,19(3-4):241-246
I trace the evolution of the scientific world view in general and of the variational approach specifically, including transformation groups I then review the impact of these ideas at the atomic, nuclear and particle levels. 相似文献
122.
Yuval Peres 《Israel Journal of Mathematics》1988,62(1):17-31
The Kamae and Mendes France version of the Van der Corput equidistribution theorem is extended further to summability methods
different from Cesàro summability and groups different from the circle. The theorem is shown to follow naturally from consideration
of Banach limits and spectral theory. 相似文献
123.
Summary Four different location parameter models are compared within the sufficiency and deficiency concept. The starting is a location model of a Weibull type sample with shape parameter -1<a<1. Here our basic inequality concerns the approximate sufficiency of the k lower extremes. In addition, the lower extremes are approximately equal, in distribution, to
where S
m is the sum of m i.i.d. standard exponential random variables and t is the location parameter. The final step leads us to the model of extreme value processes
... 相似文献
124.
125.
Yuval Ne'eman 《Foundations of Physics》1996,26(12):1607-1615
CHN≓ (1966)was an algebraic algorithm which reproduced and extended the predictions of the non-interacting≓ quark model in the asymptotic high-energy region. It wus formulated within the conceptual framework of on- mass- shell physics and of the complex angular-momentum plane. Prior to the advent of the standard model, it was reinterpreted in terms of the Melosh transformation relating current≓ to constituent≓ quarks. It is now lied up to the QCD paradigm.Also on leave from Center for Particle Physics, University of Texas, Austin, Texas 78712. 相似文献
126.
The existence of a topological double-covering for the GL(n, R) and diffeomorphism groups is reviewed. These groups do not
have finite-dimensional faithful representations. An explicit construction and the classification of all
(n, R), n=3,4 unitary irreducible representations is presented. Infinite-component spinorial and tensorial
fields, “manifields”, are introduced. Particle content of the ladder manifields, as given by the
(3, R) “little” group, is determined. The manifields are lifted to the corresponding world spinorial and tensorial manifields
by making use of generalized infinite-component frame fields. World manifields transform w.r.t. corresponding
representations, which are constructed explicitly.
Supported in part by the Science Foundation (Belgrade). 相似文献
127.
K. W. Woooburn N. J. Vardaxis J. S. Hill A. H. Kaye J. A. Reiss D. R. Phillips 《Photochemistry and photobiology》1992,55(5):697-704
The cytotoxicity (in the dark), phototoxicity (red light) and subcellular localization (using confocal laser scanning microscopy) were determined for 15 porphyrins (1-15) in C6 glioma cells. The partition coefficient in 2-octanol was also determined for each porphyrin at pH 7.4. The cytotoxicity increased with pi (log of partition coefficient) up to pi values of +2. The 7 porphyrins with cationic side chains exhibited a classical parabolic correlation between phototoxicity and pi, with maximal activity at a pi value of approximately 1.0. There was also a significant correlation between subcellular localization and degree of phototoxicity, with the three most photosensitive porphyrins all possessing cationic side chains, and all three localizing in mitochondria. 相似文献
128.
Proteins are the main proton mediators in various biological proton circuits. Using proteins for the formation of long-range proton conductors is offering a bioinspired approach for proton conductive polymers. One of the main challenges in the field of proton conductors is to explore the local environment within the polymers, along with deciphering the conduction mechanism. Here, we show that the protonic conductivity across a protein-based biopolymer can be hindered using straightforward chemical modifications, targeting carboxylate- or amine-terminated residues of the protein, as well as exploring the effect of surface hydrophobicity on proton conduction. We further use the natural tryptophan residue as a local fluorescent probe for the inner local hydration state of the protein surface and its tendency to form hydrogen bonds with nearby water molecules, along with the dynamicity of the process. Our electrical and spectroscopic measurements of the different chemically-modified protein materials as well as the material at different water–aprotic solvent mixtures result in our fundamental understanding of the proton mediators within the material and gaining important insights on the proton conduction mechanism. Our biopolymer can be used as an attractive platform for the study of bio-related protonic circuits as well as a proton conducting biopolymer for various applications, such as protonic transistors, ionic transducers and fuel cells.Post formation modification of protein-based materials can attenuate the proton conduction efficiency resulting from change in conduction mechanism, charge carrier mobility, carrier concentrations and inner hydration layer. 相似文献
129.
130.
K.M. Bhutta J. Schmalhorst G. Reiss 《Journal of magnetism and magnetic materials》2009,321(20):3384-3390
The local topographic and conducting properties of ultra-thin MgO films with polycrystalline Ru and amorphous CoFeB as lower electrodes were investigated. The local conductance and topography of the ultra-thin MgO films (from 0.5 to 1.0 nm) were simultaneously measured with a modified conducting atomic force microscope (CAFM). The imaging force was carefully chosen in order to avoid structural damages in the insulating layers. The promising results include the decrease of the density of hotspots with large conductance with the thickness of MgO and show that an insulating barrier is obtained at 1 nm thickness. 相似文献