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91.
Journal of Solid State Electrochemistry - 相似文献
92.
Journal of Solid State Electrochemistry - 相似文献
93.
We present and study a model for the nonequilibrium statistical mechanics of protein distributions in a proliferating cell population. Our model describes how the total protein variation is shaped by two processes: variation in protein production internal to the cells and variation in division and inheritance at the population level. It enables us to assess the contribution of each of these components separately. We find that, even if production is deterministic, cell division can generate a large variation in protein distribution. In this limit we solve exactly a special case and draw an analogy between protein distribution along cell generations and stress distribution in layers of granular material. At the other limit of extremely noisy protein production, we find that the population structure restrains variation and that the details of division do not affect the tail of the distribution. 相似文献
94.
95.
We use ending laminations for Weil–Petersson geodesics to establish that bounded geometry is equivalent to bounded combinatorics for Weil–Petersson geodesic segments, rays, and lines. Further, a more general notion of non-annular bounded combinatorics, which allows arbitrarily large Dehn-twisting, corresponds to an equivalent condition for Weil–Petersson geodesics. As an application, we show theWeil–Petersson geodesic flow has compact invariant subsets with arbitrarily large topological entropy. 相似文献
96.
Qiu-Cheng Chen Zi-Ye Xiao Shachar Fite Dr. Amir Mizrahi Dr. Natalia Fridman Xuan Zhan Or Keisar Dr. Yair Cohen Prof. Dr. Zeev Gross 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(48):11383-11388
Although the affinity of metallocorroles to axial ligands is quite low, this is not the case when the chelated element is phosphorus. This work is hence focused on the mechanism of ligand exchange of six-coordinate phosphorus corroles as a tool for affecting their chemical and physical properties. These fundamental investigations allowed for the development of facile methodologies for the synthesis of a large series of complexes and the establishment of several new structure/activity profiles that may be used to understand and predict spectroscopic features and for tailor-made modification of photophysical and electrochemical properties. This is exemplified by the facile access to complexes with terminal groups that are of large potential for practical applications based on click chemistry, optical imaging, and surface science. 相似文献
97.
Parallel application of block-iterative methods in medical imaging and radiation therapy 总被引:9,自引:0,他引:9
Yair Censor 《Mathematical Programming》1988,42(1-3):307-325
Some row-action algorithms which exploit special objective function and constraints structure have proven advantageous for solving huge and sparse feasibility or optimization problems. Recently developed block-iterative versions of such special-purpose methods enable parallel computation when the underlying problem is appropriately decomposed. This opens the door for parallel computation in image reconstruction problems of computerized tomography and in the inverse problem of radiation therapy treatment planning, all in their fully discretized modelling approach. Since there is more than one way of deriving block-iterative versions of any row-action method, the choice has to be made with reference to the underlying real-world problem.This research was done with partial support of National Institutes of Health, Grant HL-28438 while the author was with the Medical Image Processing Group (MIPG) at the Department of Radiology, Hospital of the University of Pennsylvania, Philadelphia, PA, USA. 相似文献
98.
Yair Censor 《Journal of Mathematical Analysis and Applications》1985,106(1):19-25
The problem of solving iteratively a large and possibly sparse system of interval linear inequalities α ? Ax ? β is considered. An algorithm of the row-action type is proposed which, in each iterative step, effectively takes account of a pair of inequalities describing a single interval inequality. The algorithm realizes in an automatic manner a relaxation principle proposed by Goffin but also allows further external relaxation parameters. 相似文献
99.
100.
Shimon Gross Alexander Brandis Louise Chen Varda Rosenbach-Belkin Susanne Roehrs Avigdor Scherz Yoram Salomon 《Photochemistry and photobiology》1997,66(6):872-878
Abstract— A model for studying the efficiency of photodynamic action with a photosensitizer placed exclusively on the bacterial cell wall has been used. Bacteriochlorophyllide molecules, conjugated to rabbit immunoglobulin G (IgG), were synthesized. The conjugated pigment bacteriochlo-rophyll (Bchl)-IgG bound with high specificity to protein-A residues naturally exposed on the cell wall of the bacterium Staphylococcus aureus Cowan I. In bacterial suspensions the phototoxicity of the targeted conjugates (0.5-2.5 pigment per IgG molecule) was dose dependent (LD50 = 1.7 μ M ) in the presence of light (Λ > 550 nm) and inhibited by native IgG but not by ovalbumin, suggesting selective interaction with protein-A on the bacterial cell wall. No dark toxicity was noticed even with the highest conjugate concentration tested. In contrast, the photocytotoxicity of bacteriochlorophyll-serine (Bchl-Ser, LD50 = 0.07 μ M ) used as a nontargeted control was not inhibited by IgG. In spite of its lower apparent potency, Bchl-IgG was found to be 30 times more efficacious than Bchl-Ser: At LD50 , only 66000 Bchl-IgG molecules were bound per bacterium compared to 1900 000 molecules of Bchl-Ser. The higher efficacy of Bchl-IgG is explained by its exclusive position on the bacterial cell wall. Consequently, photogeneration of oxidative species is confined to the cell wall and its vicinity, a seemingly highly susceptible domain for photodynamic action. In considering the design of cell-specific sensitizers for bacterial and cancer therapies, it would be beneficial to identify the more discretely sensitive subcellular domains as targets. 相似文献