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201.
汾渭盆地地裂缝成因研究中的若干关键问题 总被引:12,自引:0,他引:12
汾渭盆地是我国地裂缝发育最强烈的地区,地裂缝类型多样,成因复杂。本文概述了汾渭盆地地裂缝的分布规律,分析了目前汾渭盆地地裂缝成因研究中存在的主要问题,重点围绕构造型地裂缝的成因问题,提出如下研究思路:通过多学科联合手段,重点研究汾渭盆地地裂缝灾害的分布规律及其与活动构造的分布关系与成生联系,建立构造地裂缝的地质结构模型;将现代物理数值模拟技术与高精度观测技术相结合,分析研究构造活动启动地裂缝灾害的力学机理以及构造作用与抽水作用耦合致裂机理;以GPS观测资料为约束,将汾渭盆地地裂缝的成生与青藏、华北大陆变形的动力学过程联系起来,研究该区地裂缝与现今中国大陆动力学的内在联系,揭示大陆驱动力产生地质灾害的动力学机制与模式。 相似文献
202.
Natalia Terenti Gavril-Ionel Giurgi Lorant Szolga Ioan Stroia Anamaria Terec Ion Grosu Andreea Petronela Crian 《Molecules (Basel, Switzerland)》2022,27(4)
Four acceptor–donor–acceptor (A–D–A)-type molecules bearing indacenodithiophene as donating central core and various end-capping acceptor units have been designed and synthesised as n-type materials suitable for organic solar cells (OSCs). The studied optical and electrochemical properties supported by theoretical calculations revealed that the nature and the strength of the terminal groups exert a decisive influence on the polymer bulk-heterojunction OSC performance. 相似文献
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204.
V. A. Shcherbacov A. Kh. Tabarov D. I. Puşcaşu 《Journal of Mathematical Sciences》2009,163(6):785-795
Conditions when a congruence of a left (right) division groupoid and a left (right) cancellation groupoid is closed (“normal”)
are given. Conditions for the simplicity of the above-mentioned groupoids are obtained. 相似文献
205.
Elvan Üstün Aykut Özgür Kübra A. Coşkun Serpil Demir Düşünceli İsmail Özdemir Yusuf Tutar 《Transition Metal Chemistry》2017,42(4):331-337
Carbon monoxide is an important signaling molecule which is produced by heme oxygenase-1. CO shows antiproliferative activity against cancer cells; hence, activation of HO-1 is a significant inhibition strategy against tumor formation and survival of cancer cells. In this work, manganese-based CO-releasing molecules (CORMs) were designed and synthesized to inhibit breast cancer cell proliferation. Human invasive ductal breast cancer cells (MCF-7) were treated with the synthesized CORMs to investigate the effect of the complexes on breast cancer survival under UV light. In vitro experiments indicated that the complexes inhibited breast cancer cell proliferation, and further, the antiproliferative effects were increased under UV light. Thus, these novel CORMs may provide a drug template for the treatment of invasive ductal breast cancer. 相似文献
206.
Cobalt-modified nickel-zinc catalyst CuNi(Zn)Co is prepared on a copper substrate by using electrodeposition. Its catalytic efficiency for methanol oxidation is studied with cyclic voltammetry, chronoamperometry, and chronopotentiometry techniques. The surface morphology and chemical composition of catalyst are characterized by scanning electron microscopy and energy dispersive X-ray spectroscopy. The oxidation kinetic parameters activation energy (Ea), active species on the surface (Γ), and rate constant (k) are determined from cyclic voltammograms which are performed at different methanol concentrations and temperatures. The results show that Ni(Zn)Co catalyst has higher catalytic activity than Ni, Co, and NiZn coatings as a composite catalyst for a promising choice of methanol electrooxidation in the alkaline medium. 相似文献
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209.
Fatma Başak Aydemir Akın Günay Figen Öztoprak Ş. İlker Birbil Pınar Yolum 《Journal of Global Optimization》2013,57(2):499-519
This paper proposes the use of multiagent cooperation for solving global optimization problems through the introduction of a new multiagent environment, MANGO. The strength of the environment lays in its flexible structure based on communicating software agents that attempt to solve a problem cooperatively. This structure allows the execution of a wide range of global optimization algorithms described as a set of interacting operations. At one extreme, MANGO welcomes an individual non-cooperating agent, which is basically the traditional way of solving a global optimization problem. At the other extreme, autonomous agents existing in the environment cooperate as they see fit during run time. We explain the development and communication tools provided in the environment as well as examples of agent realizations and cooperation scenarios. We also show how the multiagent structure is more effective than having a single nonlinear optimization algorithm with randomly selected initial points. 相似文献
210.
A novel synthesis of highly enantioenriched dipeptides containing homophenylalanine is described. The process involves a crystallisation-induced asymmetric transformation (CIAT) in a Michael addition followed by exhaustive reduction. A unique example of a formally stereodivergent CIAT in conjugate addition of an achiral N-nucleophile to enantiomerically pure Michael acceptor has been discovered. 相似文献