全文获取类型
收费全文 | 317篇 |
免费 | 9篇 |
专业分类
化学 | 191篇 |
晶体学 | 11篇 |
数学 | 30篇 |
物理学 | 94篇 |
出版年
2017年 | 5篇 |
2016年 | 3篇 |
2015年 | 8篇 |
2014年 | 8篇 |
2013年 | 13篇 |
2012年 | 7篇 |
2011年 | 11篇 |
2010年 | 4篇 |
2009年 | 6篇 |
2008年 | 11篇 |
2007年 | 14篇 |
2006年 | 4篇 |
2005年 | 7篇 |
2004年 | 9篇 |
2003年 | 12篇 |
2002年 | 10篇 |
2001年 | 10篇 |
2000年 | 8篇 |
1999年 | 9篇 |
1998年 | 3篇 |
1997年 | 2篇 |
1996年 | 5篇 |
1995年 | 10篇 |
1994年 | 7篇 |
1993年 | 8篇 |
1992年 | 6篇 |
1991年 | 9篇 |
1990年 | 5篇 |
1989年 | 10篇 |
1988年 | 6篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1984年 | 8篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1980年 | 5篇 |
1979年 | 5篇 |
1978年 | 6篇 |
1977年 | 5篇 |
1976年 | 9篇 |
1975年 | 6篇 |
1974年 | 6篇 |
1973年 | 3篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1966年 | 2篇 |
1961年 | 1篇 |
排序方式: 共有326条查询结果,搜索用时 15 毫秒
321.
Dr. Ken Niwa Kentaro Suzuki Prof. Dr. Shunsuke Muto Prof. Dr. Kazuyoshi Tatsumi Prof. Dr. Kazuo Soda Dr. Takumi Kikegawa Prof. Dr. Masashi Hasegawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(43):13885-13888
The last remaining marcasite‐type RuN2 was successfully synthesized by direct chemical reaction between ruthenium and molecular nitrogen above the pressure of 32 GPa. For the first time, we found that Ru 4d is weakly hybridized with N 2p in the structure by using transmission electron microscopy equipped with electron‐energy‐loss spectroscopy. Our finding give important knowledge about the platinum‐group pernitride with respect to the chemical bonding between platinum‐group element and nitrogen. 相似文献
322.
Ryosuke Takise Kei Muto Prof. Dr. Junichiro Yamaguchi Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2014,53(26):6791-6794
The nickel‐catalyzed α‐arylation of ketones with readily available phenol derivatives (esters and carbamates) provides access to useful α‐arylketones. For this transformation, 3,4‐bis(dicyclohexylphosphino)thiophene (dcypt) was identified as a new, enabling, air‐stable ligand for this transformation. The intermediate of an assumed C? O oxidative addition was isolated and characterized by X‐ray crystal‐structure analysis. 相似文献
323.
Naruki M Fukao Y Funahashi H Ishino M Kanda H Kitaguchi M Mihara S Miwa K Miyashita T Murakami T Nakura T Sakuma F Togawa M Yamada S Yoshimura Y En'yo H Muto R Tabaru T Yokkaichi S Chiba J Ieiri M Sasaki O Sekimoto M Tanaka KH Hamagaki H Ozawa K 《Physical review letters》2006,96(9):092301
The invariant mass spectra of e+e- pairs produced in 12 GeV proton-induced nuclear reactions are measured at the KEK Proton Synchrotron. On the low-mass side of the meson peak, a significant enhancement over the known hadronic sources has been observed. The mass spectra, including the excess, are well reproduced by a model that takes into account the density dependence of the vector meson mass modification, as theoretically predicted. 相似文献
324.
Enrique Artal Bartolo Shinzo Bannai Taketo Shirane Hiro-o Tokunaga 《Mathematische Nachrichten》2023,296(6):2214-2235
There is a close relationship between the embedded topology of complex plane curves and the (group-theoretic) arithmetic of elliptic curves. In a recent paper, we studied the topology of some arrangements of curves that include a special smooth component, via the torsion properties induced by the divisors in the special curve associated to the remaining components, which is an arithmetic property. When this special curve has maximal flexes, there is a natural isomorphism between its Jacobian variety and the degree zero part of its Picard group. In this paper, we consider curve arrangements that contain a special smooth component with a maximal flex and exploit these properties to obtain Zariski tuples, which show the interplay between topology, geometry, and arithmetic. 相似文献
325.
30wt% solid content, anionic seed copolymer latex P(methyl acrylate-co-methyl methacrylate) was prepared by conventional emulsion polymerization, and then the seeded emulsion polymerization was carried out accompanied with the electrostatic coagulation during the reaction in the presence of counter-ion species, such as cationic monomer and initiator. In this article, effects of cationic monomer (dimethyl aminoethyl methacrylate, DM) content, secondary monomer to seed polymer weight ratio, M/P and amount of emulsifier (polyoxyethylene nonylphenylether with 23 units of ethylene oxide, PEO23) were investigated on the effective particle growth and the stability of final latex. With 10wt% DM in monomer, M/P ratio at 2.0 were recommended. An optimal policy for handling the emulsifier content without the nucleation of secondary particles while achieving the controlled coagulative growth was proposed from the observations of polymer yield and particle size during the polymerization. 相似文献
326.
In a previous study, it was found that monodisperse polystyrene (PSt) hollow particles can be prepared under special conditions by combining a Shirasu Porous Glass (SPG) emulsification technique and subsequent suspension polymerization process. The dispersed phase mainly containing St, hexadecane (HD), and initiator, was pressed through the uniform pores of a SPG membrane into the continuous phase to form uniform droplets. Then, the droplets were polymerized at 70°C. It was proposed that rapid phase separation between PSt and HD was a main reason responsible for the formation of hollow particle. Rapid phase separation confined the HD inside the droplets, it belonged to a non-equilibrium morphology. In this study, HD/St ratio was increased to a high value to confirm the above proposition by promoting rapid phase separation further between HD and PSt, to prevent monomer diffusion into aqueous phase, and to obtain hollow particle with a large hole. 相似文献