全文获取类型
收费全文 | 513篇 |
免费 | 0篇 |
专业分类
化学 | 280篇 |
晶体学 | 5篇 |
力学 | 3篇 |
数学 | 100篇 |
物理学 | 125篇 |
出版年
2021年 | 3篇 |
2019年 | 3篇 |
2018年 | 3篇 |
2017年 | 4篇 |
2016年 | 3篇 |
2015年 | 5篇 |
2014年 | 4篇 |
2013年 | 21篇 |
2012年 | 12篇 |
2011年 | 16篇 |
2010年 | 10篇 |
2009年 | 11篇 |
2008年 | 23篇 |
2007年 | 21篇 |
2006年 | 19篇 |
2005年 | 21篇 |
2004年 | 19篇 |
2003年 | 13篇 |
2002年 | 14篇 |
2001年 | 9篇 |
2000年 | 17篇 |
1999年 | 7篇 |
1997年 | 14篇 |
1996年 | 15篇 |
1995年 | 13篇 |
1994年 | 8篇 |
1993年 | 8篇 |
1992年 | 11篇 |
1991年 | 9篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 10篇 |
1987年 | 7篇 |
1986年 | 4篇 |
1985年 | 5篇 |
1984年 | 10篇 |
1983年 | 9篇 |
1982年 | 6篇 |
1981年 | 5篇 |
1980年 | 8篇 |
1979年 | 4篇 |
1978年 | 11篇 |
1977年 | 8篇 |
1976年 | 11篇 |
1975年 | 9篇 |
1974年 | 11篇 |
1973年 | 11篇 |
1972年 | 4篇 |
1970年 | 4篇 |
1897年 | 2篇 |
排序方式: 共有513条查询结果,搜索用时 0 毫秒
91.
92.
The (p, 2p) cross sections on 2H, 3He and 4He were measured at 65, 85 and 100 MeV. The experimental data show rather strong energy and target mass dependence, particularly for 4He. 相似文献
93.
H. Roos 《Reports on Mathematical Physics》1978,14(2):161-170
A microcanonical system oΛ is considered together with a manometer Λ. The thermodynamic limit Λ → ∞ is taken for the system Λ composed of oΛ and Λ. This yields a definition of the pressure P(v, ε) of for given values ε and v of the energy and particle densities. P(v, ε) is shown to be equal to the thermodynamic function p(z, β) derived from the grand canonical ensemble for almost all values of ε and v provided the appropriate equilibrium values of the temperature β?1 and the chemical potential μ = β?1 log z are inserted. 相似文献
94.
95.
We prove, correct and extend several results of an earlier paperof ours (using and recalling several of our later papers) aboutthe derived functors of projective limit in abelian categories.In particular we prove that if C is an abelian category satisfyingthe Grothendieck axioms AB3 and AB4* and having a set of generatorsthen the first derived functor of projective limit vanisheson so-called Mittag-Leffler sequences in C. The recent examplesgiven by Deligne and Neeman show that the condition that thecategory has a set of generators is necessary. The conditionAB4* is also necessary, and indeed we give for each integerm 1 an example of a Grothendieck category Cm and a Mittag-Lefflersequence in Cm for which the derived functors of its projectivelimit vanish in all positive degrees except m. This leads toa systematic study of derived functors of infinite productsin Grothendieck categories. Several explicit examples of theapplications of these functors are also studied. 相似文献
96.
The near-infrared electronic spectrum of AuO(1) has been re-examined in light of the new microwave data on the v = 0 and v = 1 vibrations of the X(2)Pi(3/2) state of AuO. The two observed bands in the spectrum, with red-degraded bandheads located at 10726 and 10665 cm(-1), have been reanalyzed. New theoretical work on AuO clarifies the electronic structure, and the bands in the infrared are now assigned as the (0,1) and (1,2) bands of the a(4)Sigma(-)(3/2) - X(2)Pi(3/2) transition, respectively. 相似文献
97.
Learning locally minimax optimal Bayesian networks 总被引:1,自引:0,他引:1
98.
Abstract The effects of temperature are discussed when the ZnS:Cu,Al,Au (P22G) phosphor powder is bombarded by a 2 keV electron beam with a current density of 88 mA/cm2 at an oxygen pressure of 2 × 10?6 Torr at temperatures between 25 and 300°C. The rate of surface reaction decreases at higher temperatures due to the reduction in the mean stay time of the O2 on the surface which is vital for the reactions according to an electron stimulated surface chemical reaction model. A direct correlation between the temperature and the initial cathodoluminescence (CL) brightness which depicts thermal quenching of the CL was observed. 相似文献
99.
Christopher Roos Volker Buss 《Journal of inclusion phenomena and macrocyclic chemistry》1997,27(1):49-56
Based on the analysis of UV/Vis-and CD spectra of several cyanine dyes in - and -cyclodextrin a case is made for the aggregation of the dyes into oligomers. The criteria for this new type of aggregates are: (i) the appearance of a concentration and temperature dependent shoulder on the high energy side of the dimer band in the UV/Vis-spectra; (ii) two oppositely signed high intensity CD absorptions, one centered at the shoulder, the other at about the energy of the monomer absorption. Calculations based on coupled-oscillator theory support the contention that chiral dye aggregates are formed in the presence of cyclodextrins, most probably trimers and tetramers. From UV/Vis- and CD-data a helically twisted sandwich structure is suggested for these aggregates. In contrast to the reported inclusion complexes these aggregates must form — at least partly — outside the chiral host. 相似文献
100.
A. Gehring S. Goy P. Müller O. Roos Br. Tacke Th. Arnd J. von Csiky G. von Eperjessy H. Kappen R. A. Kutschinsky S. T. Jensen St Kühn S. N. Aleschin O. Lemmermann J. König J. Hasenbäumer A. A. J. v. 'Sigmond A. Němec H. Neubauer L. Dworak K. Hesse M. Gračanin Hempelmann L. Fresenius H. Fischer E. Blanck W. Jessen W. Lesch E. Hoffmann B. Dirks F. Scheffer E. Becker R. Balks H. Elleder M. Gerlach Th. Römer A. Densch E. A. Mitscherlich H. Vageler R. Meyer H. Opitz K. H. Rathsack H. Niklas H. Poschenrieder J. Trischler J. Lanik Anna Koppová O. Wehrmann O. Eckstein A. Jacob G. N. Hoffer 《Analytical and bioanalytical chemistry》1932,90(11-12):456-480