全文获取类型
收费全文 | 399篇 |
免费 | 4篇 |
专业分类
化学 | 171篇 |
晶体学 | 5篇 |
力学 | 20篇 |
数学 | 39篇 |
物理学 | 168篇 |
出版年
2022年 | 3篇 |
2018年 | 4篇 |
2017年 | 4篇 |
2016年 | 6篇 |
2015年 | 6篇 |
2014年 | 10篇 |
2013年 | 13篇 |
2012年 | 24篇 |
2011年 | 22篇 |
2010年 | 19篇 |
2009年 | 11篇 |
2008年 | 16篇 |
2007年 | 22篇 |
2006年 | 19篇 |
2005年 | 22篇 |
2004年 | 20篇 |
2003年 | 9篇 |
2002年 | 17篇 |
2001年 | 7篇 |
2000年 | 10篇 |
1999年 | 4篇 |
1998年 | 7篇 |
1997年 | 4篇 |
1996年 | 6篇 |
1995年 | 5篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 5篇 |
1989年 | 6篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 3篇 |
1978年 | 5篇 |
1976年 | 3篇 |
1975年 | 4篇 |
1974年 | 2篇 |
1973年 | 7篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1965年 | 2篇 |
1964年 | 2篇 |
1946年 | 2篇 |
1945年 | 2篇 |
1944年 | 2篇 |
1943年 | 6篇 |
排序方式: 共有403条查询结果,搜索用时 93 毫秒
401.
ZnAl2O4:Tb phosphor was prepared by combustion synthesis. ZnAl2O4:Tb exhibits three thermally stimulated luminescence (TSL) peaks around 150, 275 and 350 °C. ZnAl2O4:Tb exhibits optically stimulated luminescence (OSL) when stimulated with 470 nm light.Electron spin resonance (ESR) studies were carried out to identify defect centres responsible for TSL peaks observed in ZnAl2O4:Tb. Two defect centres are identified in irradiated ZnAl2O4:Tb phosphor and these centres are assigned to V and F+ centres. V centre appears to correlate with the 150 °C TSL peak, while F+ centre could not be associated with the observed TSL peaks. 相似文献
402.
Vishnu Sripriya Akondi Vineetha Menon Jerome Baudry Jana Whittle 《Molecules (Basel, Switzerland)》2022,27(3)
Most contemporary drug discovery projects start with a ‘hit discovery’ phase where small chemicals are identified that have the capacity to interact, in a chemical sense, with a protein target involved in a given disease. To assist and accelerate this initial drug discovery process, ’virtual docking calculations’ are routinely performed, where computational models of proteins and computational models of small chemicals are evaluated for their capacities to bind together. In cutting-edge, contemporary implementations of this process, several conformations of protein targets are independently assayed in parallel ‘ensemble docking’ calculations. Some of these protein conformations, a minority of them, will be capable of binding many chemicals, while other protein conformations, the majority of them, will not be able to do so. This fact that only some of the conformations accessible to a protein will be ’selected’ by chemicals is known as ’conformational selection’ process in biology. This work describes a machine learning approach to characterize and identify the properties of protein conformations that will be selected (i.e., bind to) chemicals, and classified as potential binding drug candidates, unlike the remaining non-binding drug candidate protein conformations. This work also addresses the class imbalance problem through advanced machine learning techniques that maximize the prediction rate of potential protein molecular conformations for the test case proteins ADORA2A (Adenosine A2a Receptor) and OPRK1 (Opioid Receptor Kappa 1), and subsequently reduces the failure rates and hastens the drug discovery process. 相似文献
403.
An unsteady incompressible Navier–Stokes solver that uses a dual time stepping method combined with spatially high‐order‐accurate finite differences, is developed for large eddy simulation (LES) of turbulent flows. The present solver uses a primitive variable formulation that is based on the artificial compressibility method and various convergence–acceleration techniques are incorporated to efficiently simulate unsteady flows. A localized dynamic subgrid model, which is formulated using the subgrid kinetic energy, is employed for subgrid turbulence modeling. To evaluate the accuracy and the efficiency of the new solver, a posteriori tests for various turbulent flows are carried out and the resulting turbulence statistics are compared with existing experimental and direct numerical simulation (DNS) data. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献