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101.
在已有的众多准等熵加载技术中,磁驱动准等熵加载技术具有准等熵程度高、压力范围大、实验材料种类多、效费比高等特点。利用中物院流体物理研究所建成的磁驱动准等熵压缩和高速飞片实验装置CQ-1.5(最高加载压力为50GPa),成功开展了45钢的准等熵压缩实验,对装置的主要参数进行了介绍;利用激光干涉测试系统DPS获得了45钢飞片的自由面速度历史,通过反积分处理给出了材料准等熵压缩的p-V关系。通过分析实验数据,获得了45钢3种形式的等熵方程的参数。实验获得的最高等熵压力为47.5GPa。 相似文献
102.
综合自动测试系统集成策略 总被引:5,自引:0,他引:5
从应用需求的角度来描述现代军用自动测试系统的组成与发展 ,并对自动测试系统的集成过程加以描述 ,从而讨论现阶段我国军用综合自动测试系统集成的策略。 相似文献
103.
本文描述了ESD的基本概念,介绍了电力电子集成电路的ESD保护方法和技术。最后,指出了在版图设计中应注意的一些问题。 相似文献
104.
105.
Design and fabrication of Schottky barrier diodes (SBD) with a commercial standard 0.35μm CMOS process are described.In order to reduce the series resistor of Schottky contact,interdigitating the fingers of schottky diode layout is adopted.The I-V,C-V,and S parameter are measured.The parameters of realized SBD such as the saturation current,breakdown voltage,and the Schottky barrier height are given.The SPICE simulation model of the realized SBDs is given. 相似文献
106.
Extending fixed‐grid time integration schemes for unsteady CFD applications to moving grids, while formally preserving their numerical stability and time accuracy properties, is a nontrivial task. A general computational framework for constructing stability‐preserving ALE extensions of Eulerian multistep time integration schemes can be found in the literature. A complementary framework for designing accuracy‐preserving ALE extensions of such schemes is also available. However, the application of neither of these two computational frameworks to a multistage method such as a Runge–Kutta (RK) scheme is straightforward. Yet, the RK methods are an important family of explicit and implicit schemes for the approximation of solutions of ordinary differential equations in general and a popular one in CFD applications. This paper presents a methodology for filling this gap. It also applies it to the design of ALE extensions of fixed‐grid explicit and implicit second‐order time‐accurate RK (RK2) methods. To this end, it presents the discrete geometric conservation law associated with ALE RK2 schemes and a method for enforcing it. It also proves, in the context of the nonlinear scalar conservation law, that satisfying this discrete geometric conservation law is a necessary and sufficient condition for a proposed ALE extension of an RK2 scheme to preserve on moving grids the nonlinear stability properties of its fixed‐grid counterpart. All theoretical findings reported in this paper are illustrated with the ALE solution of inviscid and viscous unsteady, nonlinear flow problems associated with vibrations of the AGARD Wing 445.6. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
107.
《Microelectronics Reliability》2014,54(9-10):1953-1958
The effects of silicon etching using the Bosch process and LPCVD oxide deposition on the performance of open TSVs are analyzed through simulation. Using an in-house process simulator, a structure is generated which contains scalloped sidewalls as a result of the Bosch etch process. During the LPCVD deposition step, oxide is expected to be thinner at the trench bottom when compared to the top; however, additional localized thinning is observed around each scallop. The scalloped structure is compared to a structure where the etching step is not performed, but rather a flat trench profile is assumed. Both structures are imported into a finite element tool in order to analyze the effects of processing on device performance. The scalloped structure is shown to have an increased resistance and capacitance when compared to the flat TSV. Additionally, the scalloped TSV does not perform as well at high frequencies, where the signal loss is shown to increase. However, the scallops allow the TSV to respond better to an applied stress. This is due to the scallops’ enhanced range of motion and displacement, meaning they can compensate for the stress along the entire sidewall and not only on the TSV top, as in the flat structure. 相似文献
108.
系统阐述了我国两化融合的本质、发展规律、阶段特征、实现途径,总结了两化融合在我国的实践和发展,最后提出了若干政策建议。通过理论研究和总结,为践行具有中国特色的两化融合之路提供借鉴和参考。 相似文献
109.
Pavel M. Polestshuk 《Journal of computational chemistry》2013,34(3):206-219
The approach for the integration over a region covered by zero‐flux surface is described. This approach based on the surface triangulation technique is efficiently realized in a newly developed program TWOE . The elaborated method is tested on several atomic properties including the source function. TWOE results are compared with those produced by using well‐known existing programs. Absolute errors in computed atomic properties are shown to range usually from 10?6 to 10?5 au. The demonstrative examples prove that present realization has perfect convergence of atomic properties with increasing size of angular grid and allows to obtain highly accurate data even in the most difficult cases. It is believed that the developed program can be bridgehead that allows to implement atomic partitioning of any desired molecular property with high accuracy. © 2012 Wiley Periodicals, Inc. 相似文献
110.
《Microelectronics Reliability》2014,54(9-10):1959-1962
Managing the emerging internal mechanical stress in chips, particularly if they are 3D stacked, is a key task to maintain performance and reliability of microelectronic products. Hence, a strong need of a physics-based simulation methodology emerges. This physics-based simulation, however, requires material parameters with high accuracy. A full-chip analysis can then be performed, balancing the need for local resolution and computing time. The key for an efficient simulation of a 3D stacked IC is a comprehensive database with material properties for multiple scales of the affected materials. Therefore, effective “composite-type” material data for several regions of interest are needed. Advanced techniques to measure FEA- and design-relevant properties such as adhesion properties and effective CTE values are presented. 相似文献