全文获取类型
收费全文 | 573篇 |
免费 | 35篇 |
国内免费 | 3篇 |
专业分类
化学 | 308篇 |
晶体学 | 7篇 |
力学 | 26篇 |
数学 | 170篇 |
物理学 | 100篇 |
出版年
2023年 | 6篇 |
2022年 | 18篇 |
2021年 | 19篇 |
2020年 | 27篇 |
2019年 | 20篇 |
2018年 | 36篇 |
2017年 | 15篇 |
2016年 | 32篇 |
2015年 | 27篇 |
2014年 | 28篇 |
2013年 | 43篇 |
2012年 | 53篇 |
2011年 | 36篇 |
2010年 | 27篇 |
2009年 | 18篇 |
2008年 | 25篇 |
2007年 | 13篇 |
2006年 | 22篇 |
2005年 | 21篇 |
2004年 | 17篇 |
2003年 | 12篇 |
2002年 | 10篇 |
2001年 | 3篇 |
2000年 | 7篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 2篇 |
1996年 | 2篇 |
1994年 | 2篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 4篇 |
1990年 | 4篇 |
1988年 | 4篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 6篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 7篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 2篇 |
1975年 | 3篇 |
1974年 | 2篇 |
1972年 | 2篇 |
1971年 | 3篇 |
1968年 | 1篇 |
排序方式: 共有611条查询结果,搜索用时 15 毫秒
601.
Tran Thi Lan Huong Le Van Cuong Pham Thu Huong Tran Phuong Thao Le-Thi-Thu Huong Phan Thi Phuong Dung Dao Thi Kim Oanh Nguyen Thi Mai Huong Hoang-Van Quan Tran Khac Vu Jisung Kim Jae-Hee Lee Sang-Bae Han Pham-The Hai Nguyen-Hai Nam 《Chemical Papers》2017,71(9):1759-1769
In our search for novel small molecules targeting histone deacetylases, we have designed and synthesized a series of novel hydroxamic acids incorporating indole moiety as a cap group (3a–l). Biological evaluation showed that these hydroxamic acids potently inhibited HDAC2 with IC50 values in submicromolar range and up to tenfold (compound 3j) better than that of SAHA (also known as suberoylanilide hydroxamic acid). In four human cancer cell lines [SW620 (colon), PC-3 (prostate), AsPC-1 (pancreatic), NCI-H23 (lung)], the synthesized compounds that exhibited potent cytotoxicity with several compounds (3k, 3l) were found to be 12- to 77-fold more cytotoxic than SAHA. Docking experiments indicated that the compounds tightly bound to HDAC2 at the active binding site with binding affinities much higher than that of SAHA. Our present results demonstrate that these novel hydroxamic acids are potential for further development as anticancer agents. 相似文献
602.
Kamzin A. S. Valiullin A. A. Khurshid H. Nemati Z. Srikanth H. Phan M. H. 《Physics of the Solid State》2018,60(2):382-389
Physics of the Solid State - FeO/Fe3O4 nanoparticles were synthesized by thermal decomposition. Electron microscopy revealed that these nanoparticles were of the core-shell type and had a spherical... 相似文献
603.
The paper focuses on stress analyses of structures subjected to excitation forces operating at resonant frequencies. The structures
are analysed experimentally using the Thermoelastic Stress Analysis (TSA) technique. Experiments are carried out for fixed-free
beams of different dimensions and materials, and also for a steel rectangular plate with clamped edges. These structures are
excited by a shaker via a stinger. For materials with low thermal conductivity, the agreement between the theory, numerical
results and experimental results is excellent. As the thermal conductivity of the material is increased, the correspondence
is not as close. This is because of non-adiabatic behaviour. The implications of these results are discussed in detail in
the paper and a means of deriving the severity of heat transfer is provided. Other factors that influence the TSA results
from structures under natural loading are also discussed. 相似文献
604.
Quoc Hung Phan 《Journal of Dynamics and Differential Equations》2017,29(3):1131-1144
We study the Liouville-type theorem for the semilinear parabolic equation \(u_t-\Delta u =|x|^a u^p\) with \(p>1\) and \(a\in {\mathbb R}\). Relying on the recent result of Quittner (Math Ann, doi: 10.1007/s00208-015-1219-7, 2015), we establish the optimal Liouville-type theorem in dimension \(N=2\), in the class of nonnegative bounded solutions. We also provide a partial result in dimension \(N\ge 3\). As applications of Liouville-type theorems, we derive the blow-up rate estimates for the corresponding Cauchy problem. 相似文献
605.
606.
We consider Ekeland’s variational principle for multivalued maps. Instead of dealing with directional perturbations in a direction of the positive cone of the image space, we perturb the map under question by a convex subset of the positive cone to get stronger and more general versions. Many example are provided to highlight relations of our results to existing ones, including their advantages. 相似文献
607.
Phan H. Giang 《International Journal of Approximate Reasoning》2012,53(1):38-53
This paper examines proposals for decision making with Dempster-Shafer belief functions from the perspectives of requirements for rational decision under ignorance and sequential consistency. The focus is on the proposals by Jaffray & Wakker and Giang & Shenoy applied for partially consonant belief functions. We formalize the concept of sequential consistency of an evaluation model and prove results about sequential consistency of Jaffray-Wakker’s model and Giang-Shenoy’s model under various conditions. We demonstrate that the often neglected assumption about two-stage resolution of uncertainty used in Jaffray-Wakker’s model actually disambiguates the foci of a belief function, and therefore, makes it a partially consonant on the extended state space. 相似文献
608.
We derive and justify a normal form reduction of the nonlinear Schrödinger equation for a general pitchfork bifurcation of the symmetric bound state that occurs in a double-well symmetric potential. We prove persistence of normal form dynamics for both supercritical and subcritical pitchfork bifurcations in the time-dependent solutions of the nonlinear Schrödinger equation over long but finite time intervals. 相似文献
609.
610.