全文获取类型
收费全文 | 343篇 |
免费 | 8篇 |
国内免费 | 59篇 |
专业分类
化学 | 133篇 |
力学 | 19篇 |
综合类 | 19篇 |
数学 | 93篇 |
物理学 | 146篇 |
出版年
2015年 | 1篇 |
2014年 | 2篇 |
2013年 | 4篇 |
2012年 | 2篇 |
2011年 | 57篇 |
2010年 | 31篇 |
2009年 | 18篇 |
2008年 | 2篇 |
2007年 | 6篇 |
2006年 | 4篇 |
2005年 | 16篇 |
2004年 | 69篇 |
2003年 | 39篇 |
2002年 | 33篇 |
2001年 | 26篇 |
2000年 | 8篇 |
1999年 | 5篇 |
1998年 | 6篇 |
1997年 | 9篇 |
1996年 | 2篇 |
1995年 | 1篇 |
1994年 | 4篇 |
1993年 | 15篇 |
1992年 | 16篇 |
1991年 | 13篇 |
1990年 | 5篇 |
1989年 | 9篇 |
1988年 | 4篇 |
1987年 | 1篇 |
1986年 | 2篇 |
排序方式: 共有410条查询结果,搜索用时 15 毫秒
101.
CAI Xin LIU JinSong & WANG ShengLie Wuhan National Laboratory for Optoelectronics School of Optoelectronic Science Engineering Huazhong University of Science Technology Wuhan China School of Science Wuhan University of Technology Wuhan 《中国科学:物理学 力学 天文学(英文版)》2010,(5)
The transverse effects of two Gauss waves mixing in a photovoltaic photorefractive crystal,i.e.,the dynamical evolutions of signal beam with different parameters,are traced numerically and experimentally.Both the one-dimensional numerical simulations and two-dimensional experimental investigations show that the self-focusing effect of signal beam becomes more obvious as the intensity of pump beam and the angle between the signal and pump beams increase.In accordance with these results,the state of two Gauss... 相似文献
102.
WANG ChunXiang XU ShunQing LV ZiQuan LI YuanYuan WANG YouJie & CHEN Tian Key Laboratory of Environment Health Ministry of Education School of Public Health Tongji Medical College Huazhong University of Science Technology Wuhan China 《中国科学:化学》2010,(5)
Persistent organic pollutants(POPs),such as dioxins,polychlorinated biphenyls(PCBs) ,and organochlorine pesticides(OCPs),which are synthetic chemicals or by-products with an intrinsic resistance to natural degradation processes,are released into the environment,resulting in the widespread dispersal and accumulation in the environment,as well as in human and ecological food chains.Due to their ubiquity in the environment and lipophilic properties,there is emerging concern over the potential risks of human ex... 相似文献
103.
基于有限势容高化学势库和无限势容低化学势库间工作的等温内可逆化学机,在循环总时间一定的条件下,应用最优控制理论导出了一类普适传质规律下对应于最大输出功时化学机循环最优构型.特例分析表明传质定律为g∝△μ(△μ为化学势差)时循环最优构型为低化学势侧工质中关键组分的化学势(或浓度)为常数,而工质与有限势容高化学势库间关键组分的化学势(或浓度)均随时间呈非线性变化且化学势之差(浓度之比)为常数的等温内可逆化学机循环;传质定律为g∝△c(△c为浓度差)时循环最优构型与传质定律g∝△μ下循环最优构型存在显著不同;当高化学势库也为无限势容化学势库时,循环最优构型由两个等化学势传质分支和两个等质量流率分支组成,且与具体的传质定律无关.本文的研究对象具有一定的普适性,研究结果对于实际化学机的优化设计与最优运行具有一定参考价值. 相似文献
104.
Hui Jing Zhang Yong Gang Hu Yong Qian Wanga Jie Zhangc a School of Environmental Science Engineering Huazhong University of Science Technology Wuhan China b State Key Laboratory of Agricultural Microbiology College of Life Science Technology Huazhong Agricultural University Wuhan China c College of Environmental Science & Technology Huangshi Institute of Technology Huangshi China 《中国化学快报》2010,(8)
<正>The possibility of direct analytical applications of ferrate(Ⅵ) solution,which was freshly electrogenerated in low-concentration NaOH electrolyte,was studied by a flow-injection-chemiluminescence(FI-CL) system.It was found that some inorganic ions, organic molecule and biomolecule could enhance the chemiluminescence emission caused by ferrate(Ⅵ)-luminol reaction.V(Ⅴ), Ca(Ⅱ),Mg(Ⅱ),phloroglucinol,and bovine hemoglobin(Hb) chosen as samples were successfully detected by this developed method.The analytical characteristics of the system for the analytes determination including linear ranges,correlation coefficients, limits of detection combined with FI analysis were studied. 相似文献
105.
邓引斌 《数学物理学报(B辑英文版)》2001,(4)
Where n is a bounded smooth dornain in RN, A.u = Z k(IVuIp--'e) is the p1aPlacei = 1operator, p 2 2, q E be, ff) are some given real number. By this result, we deduce the famousOpial inequality in RN.As we know, the solvabiliy of problem (1) resuIts from whether the minimumcan be achieved. If (2) is achieved, the attained function W(x) is the nontrivial solution ofproblem (1) corre8ponding to A = A1(p, q, n) and ^ = ^1(p, ql n) is the corresponding ndnimumeigenvalue. Since q i8 8maller … 相似文献
106.
JIAO Yong PENG LiHua & LIU PeiDe School of Mathematics Statistics Wuhan University Wuhan China 《中国科学A辑(英文版)》2008,(11)
An interpolation theorem for weak Orlicz spaces generalized by N-functions satisfying MΔ condition is given. It is proved to be true for weak Orlicz martingale spaces by weak atomic decomposition of weak Hardy martingale spaces. And applying the interpolation theorem, we obtain some embedding relationships among weak Orlicz martingale spaces. 相似文献
107.
Kerr效应对非线性Jaynes-Cummings模型场熵和缠结的影响 总被引:4,自引:2,他引:2
Phoenix和Knight提出的量子熵理论,用量子熵作为缠结程度的量度,研究了附加克尔介质依赖强度耦合Jaynes-Cummings模型场熵演化的动力学特性和原子-场的缠结特性,详细地讨论了克尔效应及初始相干光场的强弱对场熵演化特性和原子-场缠结特性的影响,并与原子反转特性相比较.结果表明:在初始相干光场较弱时(n=10),克尔介质的非线性相互作用破坏了场熵演化的周期性,原子-场不再周期消缠结.但在初始相干光场较强时(n=50),克尔介质非线性相互作用只是使场熵演化的周期性减弱,场熵的演化仍近似地有周期性,原子-场仍周期消缠结,克尔效应越强,周期越小.当克尔介质与光场强耦合相互作用时(χ/g=5),原子-场持续消缠结. 相似文献
108.
In this paper, the authors extend the definition of quasi-convex mappings and obtain the corresponding growth theorem.on the unit ball of a complex Hilbert space X. 相似文献
109.
110.
于林 《应用泛函分析学报》2003,(4)
证明了B值鞅空间,pHSr(X)和pHσr(X)的共轭分别是qKSr′(X*)与qKσr′(X*),此外还讨论了pKSr(X)和pKr(X),pKσr(X)和pK+r(X)的相互嵌入关系与Banach空间的p一致光滑性和q一致凸性之间的密切联系. 相似文献