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231.
Anna Bogomolnaia Michel Le Breton Alexei Savvateev Shlomo Weber 《International Journal of Game Theory》2007,35(2):185-204
In this paper, we consider a population represented by a continuum of individuals uniformly distributed over the unit interval
that faces a problem of location and financing of public facilities under the equal share rule. We examine three notions of
stability of emerging jurisdiction structures (stability under unanimous consent, free mobility and core) and provide a characterization
of stable structures.
Financial support for Alexei Savvateev was obtained through grants R98-0631 from the Economic Education and Research Consortium,
# NSh-1939.2003.6 School Support, Russian Foundation for Basic Research No. 04-02-17227, and the Fund for Promotion of Russian
Sciences is gratefully acknowledged. 相似文献
232.
Lior Boguslavsky Shlomo Margel 《Journal of polymer science. Part A, Polymer chemistry》2004,42(19):4847-4861
Polyacrylonitrile/polystyrene micrometer‐sized composite particles of narrow size distribution were prepared by a single‐step swelling of uniform polystyrene template microspheres with emulsion droplets of methylene chloride containing the monomer acrylonitrile and the initiator benzoyl peroxide. Methylene chloride was then evaporated carefully, followed by polymerization of acrylonitrile at 70 °C within the shrunken template particles. Polymerization of acrylonitrile also occurred at the particles' surface due to the interaction of surface polyacrylonitrile oligoradicals with acrylonitrile dissolved in the aqueous phase. Uniform polyacrylonitrile particles of higher surface area were formed by dissolving the template polystyrene polymer of the composite particles. Surface and bulk characterization of the particles were performed by methods such as FTIR, elemental analysis, TGA‐DSC, XRD, XPS, advancing contact angle, light microscope, SEM and cross‐sectional TEM. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4847–4861, 2004 相似文献
233.
We develop an algorithm to construct a convex polytopeP withn vertices, contained in an arbitrary convex bodyK inR
d
, so that the ratio of the volumes |K/P|/|K| is dominated byc ·. d/n
2/(d–1).Supported in part by the fund for the promotion of research in the Technion 相似文献
234.
We study the percolation properties of graph partitioning on random regular graphs with N vertices of degree k. Optimal graph partitioning is directly related to optimal attack and immunization of complex networks. We find that for any partitioning process (even if nonoptimal) that partitions the graph into essentially equal sized connected components (clusters), the system undergoes a percolation phase transition at f = fc = 1-2/k where f is the fraction of edges removed to partition the graph. For optimal partitioning, at the percolation threshold, we find S approximately N 0.4 where S is the size of the clusters and l approximately N 0.25 where l is their diameter. Also, we find that S undergoes multiple nonpercolation transitions for f相似文献
235.
Transitions in the dynamics of complex systems can be characterized by changes in the synchronization behavior of their components. Taking the human cardiorespiratory system as an example and using an automated procedure for screening the synchrograms of 112 healthy subjects we study the frequency and the distribution of synchronization episodes under different physiological conditions that occur during sleep. We find that phase synchronization between heartbeat and breathing is significantly enhanced during non-rapid-eye-movement (non-REM) sleep (deep sleep and light sleep) and reduced during REM sleep. Our results suggest that the synchronization is mainly due to a weak influence of the breathing oscillator upon the heartbeat oscillator, which is disturbed in the presence of long-term correlated noise, superimposed by the activity of higher brain regions during REM sleep. 相似文献
236.
Yuh Kobayashi Hideki Takayasu Shlomo Havlin Misako Takayasu 《Entropy (Basel, Switzerland)》2021,23(2)
Although the sizes of business firms have been a subject of intensive research, the definition of a “size” of a firm remains unclear. In this study, we empirically characterize in detail the scaling relations between size measures of business firms, analyzing them based on allometric scaling. Using a large dataset of Japanese firms that tracked approximately one million firms annually for two decades (1994–2015), we examined up to the trivariate relations between corporate size measures: annual sales, capital stock, total assets, and numbers of employees and trading partners. The data were examined using a multivariate generalization of a previously proposed method for analyzing bivariate scalings. We found that relations between measures other than the capital stock are marked by allometric scaling relations. Power–law exponents for scalings and distributions of multiple firm size measures were mostly robust throughout the years but had fluctuations that appeared to correlate with national economic conditions. We established theoretical relations between the exponents. We expect these results to allow direct estimation of the effects of using alternative size measures of business firms in regression analyses, to facilitate the modeling of firms, and to enhance the current theoretical understanding of complex systems. 相似文献
237.
Consider a long elastic isotropic beam with a convex cross-section and a sufficiently smooth boundary. Suppose that a self-equilibrated load is applied at each end but the sides are stress-free and there are no internal body forces. It is proved in the context of three-dimensional, nonlinear elastostatics that if the first four derivatives of the displacement vector are a priori assumed to be everywhere sufficiently small with respect to the physical constants and the geometry of the cross-section, then the strains at any point decay exponentially with the distance of the point from the nearest end.This result is an extension of known results on Saint-Venant's Principle in linear and two-dimensional nonlinear elasticity. 相似文献
238.
Einav Amit Rofeamor Obena Yi-Ting Wang Roman Zhuravel Aaron James F. Reyes Shir Elbaz Dvir Rotem Danny Porath Assaf Friedler Yu-Ju Chen Shlomo Yitzchaik 《Chemical science》2015,6(8):4756-4766
We present an integrated approach for highly sensitive identification and validation of substrate-specific kinases as cancer biomarkers. Our approach combines phosphoproteomics for high throughput cancer-related biomarker discovery from patient tissues and an impedimetric kinase activity biosensor for sensitive validation. Using non-small-cell lung cancer (NSCLC) as a proof-of-concept study, label-free quantitative phosphoproteomic analysis of a pair of cancerous and its adjacent normal tissues revealed 198 phosphoproteins that are over-phosphorylated in NSCLC. Among the differentially regulated phosphorylation sites, the most significant alteration was in residue S165 in the Hepatoma Derived Growth Factor (HDGF) protein. Hence, HDGF was selected as a model system for the electrochemical studies. Further motif-based analysis of this altered phosphorylation site revealed that extracellular-signal-regulated kinase 1/2 (ERK1/2) are most likely to be the corresponding kinases. For validation of the kinase–substrate pair, densely packed peptide monolayers corresponding to the HDGF phosphorylation site were coupled to a gold electrode. Phosphorylation of the monolayer by ERK2 and dephosphorylation by alkaline phosphatase (AP) were detected by electrochemical impedance spectroscopy (EIS) and surface roughness analysis. Compared to other methods for quantification of kinase concentration, this label-free electrochemical assay offers the advantages of ultra-sensitivity as well as higher specificity for the detection of cancer-related kinase–substrate pair. With implementation of multiple kinase–substrate biomarker pairs, we expect this integrated approach to become a high throughput platform for discovery and validation of phosphorylation-mediated biomarkers. 相似文献
239.
S. Shlomo V. M. Kolomietz G. Colò 《The European Physical Journal A - Hadrons and Nuclei》2006,30(1):23-30
Accurate assessment of the value of the incompressibility coefficient, K, of symmetric nuclear matter, which is directly related to the curvature of the equation of state (EOS), is needed to extend
our knowledge of the EOS in the vicinity of the saturation point. We review the current status of K as determined from experimental data on isoscalar giant monopole and dipole resonances (compression modes) in nuclei, by
employing the microscopic theory based on the random-phase approximation (RPA). 相似文献
240.
Shay Potash Prof. Shlomo Rozen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(17):5289-5296
The quest for obtaining conjugated oligothiophene‐containing molecules with narrower HOMO–LUMO gaps and higher oxidation and reduction potentials is the subject of this study. Molecules containing the bithiophene tetraoxide ( 2 ) and the terthiophene hexaoxide ( 3 ) moieties were prepared and studied. They were obtained by transferring oxygen atoms to the corresponding dibromo oligothiophenes with the HOF ? CH3CN complex and then cross‐coupling them with either thiophene‐ or acetylene tin derivatives. The photophysical and electrochemical studies of the products revealed that this particular class of mixed thiophenes is characterized by significantly smaller frontier orbital gaps and higher oxidation and reduction potentials compared with any other arrangement of oligothiophenes including various [all]‐S,S‐oxygenated thiophene derivatives. 相似文献