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971.
972.
We introduce mean dimensions for continuous actions of countable sofic groups on compact metrizable spaces. These generalize the Gromov–Lindenstrauss–Weiss mean dimensions for actions of countable amenable groups, and are useful for distinguishing continuous actions of countable sofic groups with infinite entropy. 相似文献
973.
Backbone rearrangement during olefin capture as the rate limiting step in molecular olefin polymerization catalysis and its effect on comonomer affinity
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Francesco Zaccaria Roberta Cipullo Peter H. M. Budzelaar Vincenzo Busico Christian Ehm 《Journal of polymer science. Part A, Polymer chemistry》2017,55(17):2807-2814
Available experimental data for several metallocenes indicate that the ethene/propene copolymerization ratio rc can be much more temperature dependent than would be expected if competing insertion transition states (TS) are rate limiting. Detailed exploration of the reaction paths reveals in several cases the existence of a “capture‐like” transition state before the actual insertion, with free energies close to the insertion TS. Movement around these transition states does not just involve monomer and chain, but also clear distortion of the ligand skeleton to allow entry of the monomer. Taking these additional TSs into account leads to much improved agreement with experiment for a series of metallocenes and a constrained geometry catalyst system. Depending on catalyst and temperature, selectivity is determined by competing insertion/insertion, capture/insertion or capture/capture. It seems likely that this is a common situation especially for highly efficient catalysts, complicating (but not preventing) prediction of copolymerization performance. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2807–2814 相似文献
974.
C. Weiland J. Krajewski R. Opila V. Pallem C. Dussarrat J. C. Woicik 《Surface and interface analysis : SIA》2014,46(6):407-417
We discuss the calculation of nondestructive compositional depth profiles from regularization of variable kinetic energy hard X‐ray photoelectron spectroscopy (VKE‐XPS) data, adapting techniques developed for angle‐resolved XPS. Simulated TiO2/Si film structures are analyzed to demonstrate the applicability of regularization techniques to the VKE‐XPS data and to determine the optimum choice of regularization function and the number of data points. We find that using a maximum entropy‐like method, when the initial model/prior thickness is similar to the simulated film thickness, provides the best results for cases where prior knowledge of the sample exists. For the simple structures analyzed, we find that only five kinetic energy spectra are necessary to provide a good fit to the data, although in general, the number of spectra will depend on the sample structure and noisiness of the data. The maximum entropy‐like algorithm is then applied to two physical films of TiO2 deposited on Si. Results suggest interfacial intermixing. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. 相似文献
975.
In [1 ]and [2 ]Xiongintroducedafractaltheoryintodynamicalsystemresearch ,measuredchaoticsetswiththeHausdorffdimensionandtheHausdorffmeasure .ZhouestimatedtheHausdorffmeasureoffinitetypesubsetin [3].Inthispaper ,theHausdorffmeasuretheoreticentropyofasubshiftins… 相似文献
976.
Brian H. Gilding Roberto Natalini Alberto Tesei 《Transactions of the American Mathematical Society》2000,352(4):1797-1824
A rather complete study of the existence and qualitative behaviour of the boundaries of the support of solutions of the Cauchy problem for nonlinear first-order and second-order scalar conservation laws is presented. Among other properties, it is shown that, under appropriate assumptions, parabolic interfaces converge to hyperbolic ones in the vanishing viscosity limit.
977.
Dr. Jean-François Gaucher Dr. Marie Reille-Seroussi Dr. Sylvain Broussy 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(48):e202200465
Macrocyclization constraints are widely used in the design of protein ligands to stabilize their bioactive conformation and increase their affinities. However, the resulting changes in binding entropy can be puzzling and uncorrelated to affinity gains. Here, the thermodynamic (Isothermal Titration Calorimetry) and structural (X-ray, NMR and CD) analysis of a complete series of lactam-bridged peptide ligands of the vascular endothelial growth factor, and their unconstrained analogs are reported. It is shown that differences in thermodynamics arise mainly from the folding energy of the peptide upon binding. The systematic reduction in conformational entropy penalty due to helix pre-organization can be counterbalanced by an unfavorable vibrational entropy change if the constraints are too rigid. The gain in configurational entropy partially escapes the enthalpy/entropy compensation and leads to an improvement in affinity. The precision of the analytical ITC method makes this study a possible benchmark for constrained peptides optimization. 相似文献
978.
Richard W. Haid Xing Ding Theophilus Kobina Sarpey Aliaksandr S. Bandarenka Batyr Garlyyev 《Current Opinion in Electrochemistry》2022
Understanding the electrical double-layer structure is of paramount importance for designing efficient electrochemical energy conversion systems. Under this aspect, this short review explores the influence of the electrolyte on parameters such as the double-layer capacitance and the potential of maximum entropy. Investigation of those parameters offers a deeper understanding on how the interfacial structure changes near reaction conditions. As a consequence, one can tune the catalyst activity by creating a more favorable environment in the electrolyte. The aim of this short review is to provide the reader with recent studies examining the electrode/electrolyte interface from experimental and theoretical standpoints. 相似文献
979.
This article investigates the behavior of a Moshinsky atom in a 1D harmonic trap. Focus is given on the theoretical foundations of confinement and its impact on the correlation between particles in the Moshinsky atom. The investigation begins by illustrating the (de)localization of the probability density function using Shannon entropy. The basics of correlation and interpretation of correlation using tools such as mutual information and statistical correlation coefficients and how these can be quantified are discussed. Then the concept of confinement is explored. The impact of interaction strength and confinement on Shannon entropy, statistical correlation coefficients, and mutual information is investigated. How interaction strength and confinement can be used to induce correlations between previously uncorrelated particles, as well as how they can be used to suppress correlations between previously correlated particles is discussed. Their implications for quantum information processing and quantum simulation are discussed. In conclusion, confinement is a powerful tool for controlling correlations in quantum systems, and its impact on correlation can be understood through theoretical models. The importance of experimental studies in this field, which provide insights into the behavior of quantum systems under confinement and pave the way for future applications in quantum technology is also emphasized. 相似文献
980.