全文获取类型
收费全文 | 1544篇 |
免费 | 46篇 |
国内免费 | 3篇 |
专业分类
化学 | 1284篇 |
晶体学 | 15篇 |
力学 | 18篇 |
数学 | 101篇 |
物理学 | 175篇 |
出版年
2023年 | 5篇 |
2021年 | 7篇 |
2020年 | 8篇 |
2019年 | 18篇 |
2018年 | 20篇 |
2017年 | 7篇 |
2016年 | 36篇 |
2015年 | 31篇 |
2014年 | 41篇 |
2013年 | 80篇 |
2012年 | 70篇 |
2011年 | 84篇 |
2010年 | 56篇 |
2009年 | 33篇 |
2008年 | 82篇 |
2007年 | 63篇 |
2006年 | 80篇 |
2005年 | 70篇 |
2004年 | 74篇 |
2003年 | 92篇 |
2002年 | 75篇 |
2001年 | 22篇 |
2000年 | 54篇 |
1999年 | 24篇 |
1998年 | 18篇 |
1997年 | 24篇 |
1996年 | 26篇 |
1995年 | 23篇 |
1994年 | 22篇 |
1993年 | 21篇 |
1992年 | 20篇 |
1991年 | 18篇 |
1990年 | 16篇 |
1989年 | 6篇 |
1988年 | 15篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 20篇 |
1984年 | 22篇 |
1983年 | 9篇 |
1982年 | 20篇 |
1981年 | 22篇 |
1980年 | 24篇 |
1979年 | 26篇 |
1978年 | 22篇 |
1977年 | 13篇 |
1976年 | 14篇 |
1974年 | 8篇 |
1973年 | 10篇 |
1968年 | 5篇 |
排序方式: 共有1593条查询结果,搜索用时 15 毫秒
151.
Yoshiyuki Kani Shigeru Ohba Sayo Ito Yuzo Nishida 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e201-e201
The structure of the title compound, [Cu2(C19H18N3O)2](ClO4)2, was reported with insufficient accuracy because of a twinning problem by Adams, Bailey, Campbell, Fenton & He [J. Chem. Soc. DaltonTrans. (1996), pp. 2233–2237]. The dinuclear phenolate‐bridged CuII complex has an inversion centre. 相似文献
152.
153.
Yuuki Hirayama Kentaro Yamaguchi Shigeru Sakamoto Michiko Iwamura 《Tetrahedron letters》2005,46(6):1027-1030
A new AB2 type building block for synthesis of dendritic compounds is made starting from Michael addition of 2 equiv of 3-hydroxyacetophenone to acrylate, followed by decarboxylation and deprotection of either carboxyl or hydroxyl protecting groups. [G1]-[G4] dendrons and [G2] dendrimer were synthesized by the reiterative [hydrogenolysis then DCC/DPTS coupling] sequence using a combination of convergent and divergent growth methods. 相似文献
154.
155.
Hori A Kataoka H Okano T Sakamoto S Yamaguchi K Fujita M 《Chemical communications (Cambridge, England)》2003,(2):182-183
The reversible cross-catenation of two different coordination rings (Pd(II)- and Pt(II)-linked rings) has been achieved by using the labile nature of the Pd-N interaction and efficient hydrophobic contact between the rings. 相似文献
156.
Ryota Kikuchi Takashi Misaka Shigeru Obayashi 《International Journal of Computational Fluid Dynamics》2016,30(4):285-306
An integrated method consisting of a proper orthogonal decomposition (POD)-based reduced-order model (ROM) and a particle filter (PF) is proposed for real-time prediction of an unsteady flow field. The proposed method is validated using identical twin experiments of an unsteady flow field around a circular cylinder for Reynolds numbers of 100 and 1000. In this study, a PF is employed (ROM-PF) to modify the temporal coefficient of the ROM based on observation data because the prediction capability of the ROM alone is limited due to the stability issue. The proposed method reproduces the unsteady flow field several orders faster than a reference numerical simulation based on Navier–Stokes equations. Furthermore, the effects of parameters, related to observation and simulation, on the prediction accuracy are studied. Most of the energy modes of the unsteady flow field are captured, and it is possible to stably predict the long-term evolution with ROM-PF. 相似文献
157.
158.
Sakihito Kitajima Kaeko Kamei Shigeru Taketani Masamitsu Yamaguchi Fumiko Kawai Aino Komatsu Yoshihiro Inukai 《BMC biochemistry》2010,11(1):6
Background
Plant latex is the cytoplasm of highly specialized cells known as laticifers, and is thought to have a critical role in defense against herbivorous insects. Proteins abundantly accumulated in latex might therefore be involved in the defense system. 相似文献159.
Shigeru Arimoto Mark Spivakovsky Hiromu Ohno Peter Zizler Keith F. Taylor Tokio Yamabe Paul G. Mezey 《International journal of quantum chemistry》2001,84(4):389-400
The present Part VI of this series of articles provides a mathematical and methodical link between (i) fundamental methodology in the repeat space theory (RST), which is referred to as the approach via the aspect of form and general topology and which has universal unifying power to handle additivity problems of molecules that have many identical moieties, and (ii) frontier electron theory of reactivity indices. Using theoretical tools required to link (i) and (ii), we establish a theorem from which the Generalized Alpha Existence Theorem (a theorem essential in the RST and proved in the previous Part V) directly follows. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem 84: 389–400, 2001 相似文献
160.
Noriko Hata Shiho Hieda Mika Yamada Rie Yasui Hideki Kuramitz Shigeru Taguchi 《Analytical sciences》2008,24(7):925-928
The formation of a liquid organic ion associate in an aqueous sample was applied to the concentration and determination of cadmium in environmental water samples. Cadmium was converted into a complex with 2-(5-bromo-2-pyridylazo)-5-(N-propyl-N-sulfopropylamino)phenol (5-Br-PAPS) in a 40-mL sample solution, and was extracted into a liquid ion associate of phenolsulfonate and benzethonium during phase formation. More than 400-fold enrichment was easily attained by this technique, because the volume of the liquid organic phase formed was very small, ca. 2 microL. After dilution of the organic phase with a small volume of 2-methoxyethanol, the cadmium in the solution was determined by GF-AAS. The detection limit was 0.09 ng/L (3sigma(b)). This method was applied to the determination of cadmium in river water and seawater. 相似文献