全文获取类型
收费全文 | 647篇 |
免费 | 19篇 |
国内免费 | 3篇 |
专业分类
化学 | 530篇 |
晶体学 | 9篇 |
力学 | 5篇 |
综合类 | 1篇 |
数学 | 12篇 |
物理学 | 112篇 |
出版年
2021年 | 6篇 |
2020年 | 11篇 |
2019年 | 3篇 |
2018年 | 8篇 |
2017年 | 8篇 |
2016年 | 8篇 |
2015年 | 5篇 |
2014年 | 15篇 |
2013年 | 23篇 |
2012年 | 30篇 |
2011年 | 28篇 |
2010年 | 20篇 |
2009年 | 20篇 |
2008年 | 32篇 |
2007年 | 37篇 |
2006年 | 47篇 |
2005年 | 49篇 |
2004年 | 41篇 |
2003年 | 35篇 |
2002年 | 34篇 |
2001年 | 3篇 |
2000年 | 13篇 |
1999年 | 7篇 |
1998年 | 11篇 |
1997年 | 9篇 |
1996年 | 6篇 |
1995年 | 8篇 |
1994年 | 11篇 |
1993年 | 13篇 |
1992年 | 11篇 |
1991年 | 8篇 |
1990年 | 7篇 |
1989年 | 13篇 |
1988年 | 5篇 |
1987年 | 12篇 |
1986年 | 14篇 |
1985年 | 16篇 |
1984年 | 6篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1976年 | 2篇 |
1975年 | 5篇 |
1974年 | 5篇 |
1973年 | 7篇 |
1972年 | 1篇 |
1970年 | 1篇 |
排序方式: 共有669条查询结果,搜索用时 15 毫秒
141.
Cheng Yang Gaku Fukuhara Asao Nakamura Yumi Origane Tadashi Mori Takehiko Wada Yoshihisa Inoue 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):433-437
The complexation behavior of 6-amino-6-deoxy-γ-cyclodextrin (CD), 6A,6X-diamino-6A,6X-deoxy-γ-CDs and 3A-amino-3A-deoxy-altro-γ-CD with 2-anthracenecarboxylic acid (AC) was studied by NMR, UV–vis and circular dichroism spectroscopy. These modified γ-CD derivatives were found to form stable 1:2 host-guest ternary complexes with AC in aqueous solution. Compared with native
γ-CD, the primary-face-aminated γ-CDs exhibited remarkably enhanced overall association constants as a result of the additional electrostatic interactions
between the oppositely charged host and guest. In contrast, the ternary complex formation of the secondary-face-aminated γ-CD with AC was hindered. 相似文献
142.
Yoshihisa Kurasawa Yumiko Kamigaki Ho Sik Kim Keiko Yonekura Atsushi Takada Yoshihisa Okamoto 《Journal of heterocyclic chemistry》1989,26(3):869-870
Dihydropyrazolo[5, 1-c][1, 2, 4]triazines 6, 7 and 8 were found to predominate as the 4, 6-dihydro tautomeric form in solution by the measurement of ID NOE different spectra. 相似文献
143.
The dithia[3.3]pyridinophane consisting of two pyridine rings has been found out to assume the syn-structure by the X-ray crystallography, meaning the two nitrogen atoms point in the same direction. From this cyclophane and cis-protected palladium(II), the self-assembled coordination molecular cage has been constructed. 相似文献
144.
145.
Das Kaustav Yuasa Tomonori Nishidate Izumi Funamizu Hideki Aizu Yoshihisa 《Optical Review》2020,27(2):233-245
Optical Review - This paper presents a numerical study on simulated spectra and point spread functions in the database that we constructed by moderate grouping of nine layers in a skin model. The... 相似文献
146.
Qifeng Wang Sadaki Samitsu Yoshihisa Fujii Chiaki Yoshikawa Toyohide Miyazaki Hidekuni Banno Izumi Ichinose 《Journal of Polymer Science.Polymer Physics》2015,53(9):615-620
Polymer nanoparticles are readily obtainable by rapidly mixing a dilute polymer solution and a poor solvent. The nanoparticles of poly(vinylphenol), poly(vinylidene fluoride), and emeraldine base polyaniline prepared by nanoprecipitation become sticky when their diameters decrease down to a few tens of nanometers, and such polymer nanoparticles spontaneously assemble into rigid fractal networks of the nanoparticles. By filtering these fibrous nanoparticle networks on a microfiltration membrane, ultrafiltration membranes with a thin free‐standing filter cake layer made of nanoparticles are obtainable. The nanoparticle membranes are robust at least up to the applied pressure of 2 MPa and can separate 99% of 10 nm Au nanoparticles from the aqueous dispersion at the flux of more than 1835 L m?2 h?1 even at very low pressure difference of 0.08 MPa. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 615–620 相似文献
147.
K. Aizu 《Phase Transitions》2013,86(1-4):19-23
Parts of the author's conception regarding the variety of drastic transitions between solid phases were described in different previous papers. These parts are supplemented here and integrated into this paper. 相似文献
148.
149.
Yoshihisa Morita 《Journal of Dynamics and Differential Equations》1990,2(1):69-115
A study is made of systems of weakly coupled, semilinear, parabolic equations, namely reaction-diffusion systems, subject to the homogeneous Neumann boundary conditions in parametrized nonconvex domains inR
2. It is assumed that the domain approaches a union of two disjoint domains as the parameter varies. Under some conditions the long-time behavior of bounded solutions is discussed and the existence of a finite-dimensional invariant manifold is shown, together with its attractivity. This manifold is represented by a graph of some function defined in a possibly large bounded region of the phase space, and the original system is reduced to an ODE system on it. Since an explicit form of the reduced ODE system is given, its dynamics can be studied in detail, which in turn reveals the global dynamics of the original reaction-diffusion system. One can thereby prove, among other things, the existence of asymptotically stable equilibrium solutions of the original system having large spatial inhomogeneity. The existence and stability of a spatially inhomogeneous periodic solution of large amplitude are also discussed. 相似文献
150.
Osaka I Kondou M Selvapalam N Samal S Kim K Rekharsky MV Inoue Y Arakawa R 《Journal of mass spectrometry : JMS》2006,41(2):202-207
When an intramolecular cavity exists in a molecule, it can trap another chemical species to form a host-guest complex. We examine the formation of such an inclusion complex with cucurbit[n]uril (CBn, n = 6, 7) as the host to trap alkali metal or ammonium ions as the guest, by electrospray ionization mass spectrometry (ESI-MS). The results show that the inclusion complexes are formed between the three-dimensional cylinder of CBn hosts and the guest cations. Selectivity of the complex formation is dependent both on (1) ion-dipole interactions between the cylindrical portal of the CBn hosts and the guest cations and (2) the hydrophobic interactions at the inner cavity of CBn. 相似文献