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61.
Cem Cüneyt Ersanl igdem Albayrak Mustafa Odabaog
lu Canan Kazak Ahmet Erdnmez 《Acta Crystallographica. Section C, Structural Chemistry》2004,60(6):o455-o457
The two title molecules, both C15H14N2O3, are roughly planar and display a trans conformation with respect to the –N=N– double bond, as found for other diazene derivatives. In both compounds, there are intramolecular O—H⋯O hydrogen bonds and the crystal packing is governed by weak intermolecular C—H⋯O hydrogen bonds and π–π stacking. 相似文献
62.
In the literature about algebraic geometry codes one finds a lot of results improving Goppa’s minimum distance bound. These improvements often use the idea of “shrinking” or “growing” the defining divisors of the codes under certain technical conditions. The main contribution of this article is to show that most of these improvements can be obtained in a unified way from one (rather simple) theorem. Our result does not only simplify previous results but it also improves them further. 相似文献
63.
We present here a general purpose numerical Schrödinger–Poisson solver for radially symmetric nanowire core–shell structures for electronic and optoelectronic applications. The solver provides self-consistent solutions of the Schrödinger equation and the Poisson equation in cylindrical coordinates, for nanowire core–shell structures with radial compositional variation. Quantized energy levels as well as their associated electron wavefunctions and populations can be obtained from the solutions. Individual equation solvers were verified by comparison with scenarios where analytical results exist; verification of the self-consistent solution process was done by comparing results in the large radius limit with numerical solutions for a rectangular slab structure. We apply this solver to compute the charge/capacitance–voltage characteristics for a nanowire field effect device with wrap-around gate. It is shown that quantum confinement and the low dimensionality can give rise to, for representative nanowire FETs considered, 30% reduction in gate capacitance compared to the classically predicted value, and is 1/3 of the geometrical barrier limited capacitance. 相似文献
64.
In the last years, there has been great interest to the formulation and application of wavelet transformation in variety of fields to investigate the characteristics of dynamical systems. Recently, a method based on the scalogram analysis of the continuous wavelet transform, the scale index has been proposed to measure aperiodicity and determine the transitions from aperiodic behaviour to periodic behaviour in nonlinear dynamical systems. In this work we test the scale index method by performing the analysis of the deterministic behaviour of the fermion-like two-dimensional Akdeniz–Smailagic instanton solution in Thirring Model. We show that the scale index method can also be considered to detect the periodic behaviours of the fermion-like instanton solutions. 相似文献
65.
臭氧催化氧化作为高级氧化技术是目前水处理领域研究的热点,其中非均相臭氧催化氧化技术因其氧化能力强、降低臭氧投加量特别是能显著提高有机物矿化率等优点而备受关注。非均相催化臭氧氧化领域不断研究新的催化剂,但是其反应过程及机制更加复杂。催化臭氧氧化的性能很大程度上取决于催化剂及其表面性质。污染物在催化剂表面形成络合物,或者臭氧在催化剂表面分解产生不同的含氧物种如表面氧原子、过氧化物和羟基自由基等。本文评述了非均相臭氧催化氧化反应中存在的多种机理,主要是自由基理论、氧空位理论、表面原子氧理论、表面络合物理论和臭氧直接氧化理论。催化剂表面的羟基基团是主要的催化活性中心,本文探讨了表面羟基基团催化反应机制,得出催化剂表面性质决定其表面活性位点的特性及含量,对诱导臭氧分解产生含氧活性物种起了关键作用;概述了催化剂改性后的结构形态、比表面积及其性能和作用机制;并讨论了非均相臭氧催化氧化反应催化剂未来的发展趋势,为催化臭氧氧化污水处理技术提供了理论参考。 相似文献
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67.
This paper addresses the numerical computation of nonlinear normal modes defined as two-dimensional invariant manifolds in phase space. A novel finite-element-based algorithm, combining the streamline upwind Petrov–Galerkin method with mesh moving and domain prediction–correction techniques, is proposed to solve the manifold-governing partial differential equations. It is first validated using conservative examples through the comparison with a reference solution given by numerical continuation. The algorithm is then demonstrated on nonconservative examples. 相似文献
68.
Enrique Murillo Yesury Mosquera Tibor Kurtán Gergely Gulyás‐Fekete Veronika Nagy József Deli 《Helvetica chimica acta》2012,95(6):983-988
From the ripe fruits of red mamey (Pouteria sapota), two new carotenoids, 3′‐deoxycapsorubin and 3,3′‐dideoxycapsorubin, were isolated and identified based on their UV/VIS, CD, 1H‐NMR, and mass spectral data. 相似文献
69.
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