全文获取类型
收费全文 | 389篇 |
免费 | 23篇 |
专业分类
化学 | 302篇 |
晶体学 | 1篇 |
力学 | 4篇 |
数学 | 29篇 |
物理学 | 76篇 |
出版年
2023年 | 5篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 13篇 |
2019年 | 5篇 |
2018年 | 5篇 |
2017年 | 4篇 |
2016年 | 8篇 |
2015年 | 15篇 |
2014年 | 14篇 |
2013年 | 29篇 |
2012年 | 25篇 |
2011年 | 18篇 |
2010年 | 17篇 |
2009年 | 19篇 |
2008年 | 28篇 |
2007年 | 21篇 |
2006年 | 27篇 |
2005年 | 17篇 |
2004年 | 22篇 |
2003年 | 27篇 |
2002年 | 21篇 |
2001年 | 6篇 |
2000年 | 9篇 |
1999年 | 8篇 |
1998年 | 9篇 |
1997年 | 4篇 |
1996年 | 4篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 4篇 |
1992年 | 1篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1943年 | 1篇 |
1912年 | 1篇 |
排序方式: 共有412条查询结果,搜索用时 15 毫秒
41.
Pomestchenko IE Luman CR Hissler M Ziessel R Castellano FN 《Inorganic chemistry》2003,42(5):1394-1396
Room temperature phosphorescence has been observed in a synthetically facile Pt(II) complex, Pt(dbbpy)(CtriplebondC-pyrene)(2) (dbbpy = 4,4'-di(tert-butyl)-2,2'-bipyridine; CtriplebondC-pyrene = 1-ethynylpyrene), in fluid solution. The static and time-resolved absorption and luminescence data are consistent with phosphorescence emerging from the appended CtriplebondC-pyrenyl units following excitation into the low energy dpi Pt --> pi* dbbpy metal-to-ligand charge transfer absorption bands. 相似文献
42.
43.
W. J. Firth C. T. Seaton E. M. Wright S. D. Smith M. E. Prise G. Litfin J. Mlynek F. Mitschke R. Deserno W. Lange H. J. Eichler F. Maßmann C. Zaki J. Heritage F. V. Karpushko G. V. Simitsyn J. A. Martin-Pereda M. A. Muriel P. W. Smith W. J. Tomlinson Ch. Harder K. Y. Lau A. Yariv J. C. Khoo S. Shepard S. Nahar S. L. Zhuang 《Applied physics. B, Lasers and optics》1982,28(2-3):131-141
44.
An electrochemical sensor with two soluble enzymes allows assay of 0.1–10 mM, l- carnitine with an accuracy of 2%. The assay takes about 2 min. The first enzyme, carnitine dehydrogenase, catalyzes the oxidation of l-carnitine by NAD+. The NADH formed is oxidized by hexacyanoferrate(III) in a reaction catalyzed by diaphorase, and the hexacyanoferrate(II) produced is oxidized by electrolysis at 0.3 V. The sensor can be used for several days. 相似文献
45.
van der Eerden AM Visser T Nijhuis TA Ikeda Y Lepage M Koningsberger DC Weckhuysen BM 《Journal of the American Chemical Society》2005,127(10):3272-3273
Atomic XAFS is a very attractive technique for probing electronic properties of supported metal nanoclusters. For platinum nanoparticles on different supports, the technique is found to be in good agreement with infrared CO adsorption measurements. The advantages of AXAFS, however, are that no probe molecule is required and that real-time measurements under reaction conditions are possible. 相似文献
46.
We consider the two-dimensional motion of a rigid structure immersed in an incompressible fluid governed by Navier–Stokes equations. The control force acts on a fixed subset of the fluid domain. We prove that our system is null controllable; that is, for small initial data, the system can be driven at rest and the structure can be driven to the origin at a given . The result holds for a structure symmetric with respect to the center of mass and for initial conditions satisfying strong compatibility conditions. To cite this article: M. Boulakia, A. Osses, C. R. Acad. Sci. Paris, Ser. I 343 (2006). 相似文献
47.
48.
An efficient method for the synthesis of N-acyl-benzotriazoles from a wide variety of protected amino acids, as well as from compounds frequently used in drug discovery such as biotin and N-Fmoc polyethylene glycol, has been developed. The reaction of carboxylic acid derivatives with benzotriazole in the presence of T3P® yielded the corresponding N-acyl-benzotriazoles, which were obtained in high purity following a simple work-up procedure, in most cases via precipitation of the desired product in water. 相似文献
49.
Anca‐Elena Dascalu Alina Ghinet Muriel Billamboz Emmanuelle Lipka 《Electrophoresis》2019,40(15):1986-1991
CD‐CZE methods were developed for complete stereoisomeric separations of a series of six γ‐lactam analogues, of which some were neutral, or cationic depending on the background electrolyte nature. The tested cyclodextrin was the versatile sulfobutylether‐ β‐CD, used either in a phosphate buffer using capillaries dynamically coated with polyethylene oxide or in a borate buffer using uncoated capillaries. Long‐end and short‐end modes and concentration variations of chiral selectors allowed finding conditions of complete separation of four out of the six derivatives (i.e., 1 , 2 , 3, and 4 ) in short run times, confirming their broad range of applications. To separate the two last compounds, the highly sulfated‐ γ‐CD was examined as chiral selector in acidic phosphate conditions. The enantiomers of the γ‐lactam analogues 5 and 6 were baseline resolved with 5.5 and 4%, respectively as concentration in the buffer. 相似文献
50.
We demonstrate a simple technique for the implementation of an all-optical integrator based on a uniform-period fiber Bragg grating (FBG) in reflection that is designed to present a decreasing exponential impulse response. The proposed FBG integrator is readily feasible and can perform close to ideal integration of few-picosecond and subpicosecond pulses. 相似文献