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排序方式: 共有3472条查询结果,搜索用时 15 毫秒
1.
Massoumi Sina Challamel Noël Lerbet Jean Wautier Antoine Nicot François Darve Félix 《Meccanica》2022,57(8):2043-2066
Meccanica - This study is an attempt towards a better understanding of the length scale effects on the bending response of the granular beams. To this aim, a unidimensional discrete granular chain... 相似文献
2.
Journal of Statistical Physics - We study mathematically the equilibrium properties of the Bose–Hubbard Hamiltonian in the limit of a vanishing hopping amplitude. This system conserves the... 相似文献
3.
Tran Thu Ha Nguyen Hong Phong François-Xavier Le Dimet Hong Son Hoang 《Comptes Rendus Mecanique》2019,347(5):423-444
This article presents a correction method for a better resolution of the problem of estimating and predicting pollution, governed by Burgers' equations. The originality of the method consists in the introduction of an error function into the system's equations of state to model uncertainty in the model. The initial conditions and diffusion coefficients, present in the equations for pollution and concentration, and also those in the model error equations, are estimated by solving a data assimilation problem. The efficiency of the correction method is compared with that produced by the traditional method without introduction of an error function.Three test cases are presented in this study in order to compare the performances of the proposed methods. In the first two tests, the reference is the analytical solution and the last test is formulated as part of the “twin experiment”.The numerical results obtained confirm the important role of the model error equation for improving the prediction capability of the system, in terms of both accuracy and speed of convergence. 相似文献
4.
Almeida Carolane M. de Carvalho João G. M. Fujimori Mahmi França Eduardo L. Honorio-França Adenilda C. Parreira Renato L. T. Orenha Renato P. Gatto Claudia C. 《Structural chemistry》2020,31(5):2093-2103
Structural Chemistry - The current work reports the synthesis and structural investigation of three novel complexes with 2-acetyl-pyridine-N(4)-phenylthiosemicarbazone (HL1), [Ni(L1)Cl] (1),... 相似文献
5.
Fran?ois?NicotEmail author Luc?Sibille Pierre-Yves?Hicher 《Continuum Mechanics and Thermodynamics》2015,27(1-2):173-193
When granular materials are subjected to proportional strain loading paths, they manifest a variety of behaviors depending on the initial void ratio of the specimen as well as the imposed dilatancy/contractancy rate. In some cases, the stress components may vanish over the duration of the test, and the specimen may progressively liquefy. To investigate this behavior, the authors have developed a kinematic approach to be deployed in two parts. First, numerical simulations are performed by means of a discrete element method. Secondly, two micromechanical models have corroborated the DEM results. The performance of these models may explain a number of microstructural mechanisms responsible for the macroscopic constitutive behavior. 相似文献
6.
Measurement of emerging dechloranes in human serum using modulated gas chromatography coupled to electron capture negative ionization time‐of‐flight mass spectrometry 下载免费PDF全文
7.
François N. Miros Guangxi Huang Yingjie Zhao Naomi Sakai 《Supramolecular chemistry》2015,27(5-6):303-309
Catalysis with anion–π interactions is emerging as an important topic in supramolecular chemistry. Among the reactions explored so far on π-acidic surfaces, coumarin synthesis stands out as a cascade process with several coupled anionic transition states. Increasing π-acidity has been shown in a different context to increase transition-state stabilisation and thus catalytic activity. In this report, we explore the possible use of macrocycles to accelerate coumarin synthesis between two π-acidic surfaces. To our disappointment, we found that compared to monomeric π-acids, coumarin synthesis within divalent macrocycles is clearly slower. Hindered access to an overly confined active site within the macrocycles could possibly account for this loss in activity, but several other explanations are certainly possible. However, operational coumarin synthesis on monomeric π-acidic surfaces is shown to tolerate structural modifications. Best results are obtained with structures that aim for proximity without obstructing transition-state stabilisation on the π-acidic surface. 相似文献
8.
Back Cover: Experimental and Theoretical Study of the Reactivity of Gold Nanoparticles Towards Benzimidazole‐2‐ylidene Ligands (Chem. Eur. J. 30/2016) 下载免费PDF全文
Dr. María Rodríguez‐Castillo Gustavo Lugo‐Preciado Dr. Danielle Laurencin Dr. Frederik Tielens Dr. Arie van der Lee Dr. Sébastien Clément Dr. Yannick Guari Dr. José M. López‐de‐Luzuriaga Dr. Miguel Monge Dr. Françoise Remacle Dr. Sébastien Richeter 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(30):10680-10680
9.
Sorin‐Claudiu Roşca Dr. Chiara Dinoi Dr. Elsa Caytan Dr. Vincent Dorcet Prof. Dr. Michel Etienne Prof. Dr. Jean‐François Carpentier Dr. Yann Sarazin 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(19):6505-6509
Strontium and calcium (alkaline earth: Ae) olefin complexes stabilised by secondary Ae???F?C and β‐agostic Ae???H?Si interactions are presented. Olefin coordination onto the alkaline earths is plain in the solid state, and it is thermodynamically favoured over the coordination of THF. The existence of the Ae???olefin interactions is corroborated by solution NMR data and DFT computations. The coordination mode of the olefin varies with steric effects and, if enforced, olefin dissociation can be compensated by the other non‐covalent interactions, as supported by DFT computations. 相似文献
10.