全文获取类型
收费全文 | 30282篇 |
免费 | 397篇 |
国内免费 | 424篇 |
专业分类
化学 | 11414篇 |
晶体学 | 284篇 |
力学 | 1516篇 |
综合类 | 24篇 |
数学 | 9081篇 |
物理学 | 8784篇 |
出版年
2023年 | 36篇 |
2022年 | 80篇 |
2021年 | 102篇 |
2020年 | 86篇 |
2019年 | 66篇 |
2018年 | 1256篇 |
2017年 | 1504篇 |
2016年 | 784篇 |
2015年 | 651篇 |
2014年 | 576篇 |
2013年 | 775篇 |
2012年 | 3270篇 |
2011年 | 2459篇 |
2010年 | 1888篇 |
2009年 | 1639篇 |
2008年 | 645篇 |
2007年 | 695篇 |
2006年 | 666篇 |
2005年 | 4478篇 |
2004年 | 3926篇 |
2003年 | 2310篇 |
2002年 | 499篇 |
2001年 | 309篇 |
2000年 | 121篇 |
1999年 | 197篇 |
1998年 | 130篇 |
1997年 | 89篇 |
1996年 | 73篇 |
1995年 | 54篇 |
1994年 | 59篇 |
1993年 | 32篇 |
1992年 | 174篇 |
1991年 | 167篇 |
1990年 | 157篇 |
1989年 | 122篇 |
1988年 | 109篇 |
1987年 | 67篇 |
1986年 | 48篇 |
1985年 | 38篇 |
1979年 | 30篇 |
1976年 | 81篇 |
1975年 | 37篇 |
1974年 | 40篇 |
1973年 | 48篇 |
1972年 | 39篇 |
1970年 | 34篇 |
1969年 | 37篇 |
1968年 | 35篇 |
1967年 | 30篇 |
1966年 | 37篇 |
排序方式: 共有10000条查询结果,搜索用时 36 毫秒
111.
M. Smi?anská J. Hladky M. Novák M. Vecko A. N. Aleev V. A. Arefiev V. P. Balandin V. K. Berdyshev V. K. Birulev A. S. Chvyrov et al. 《Czechoslovak Journal of Physics》1990,40(12):1293-1305
We present results of the exclusive diffractive reaction np 0K0p at 0·08 < |t|< 0·53 GeV2/c2 and momenta between 30–70 GeV/c at the Serpukhov neutron beam. Thet-dependence is exp (Bt) withB= 11·4± 2·3 (GeV/c)–2 and it exhibits the diffractive minimum at ¦t¦ 0·28 GeV2/c2 for 0K0 massesM < 1·8 GeV/c2.B decreases with increasingM. Correlation with the beam direction is observed in the rest frame of the 0K0 system: the cross section rises for the forward-going 0. The rise is more pronounced for higherM. The cross section of reaction np 0K0p for 0<|t|< 0·53 GeV2/c2 is 10·3 ± 2·5 ± 2·8 b. 相似文献
112.
N. M. Agababyan I. V. Ajinenko Yu. A. Belokopytov K. S. Belous H. Boettcher F. Botterweck M. M. Chapkin P. V. Chliapnikov F. Crijns A. De Roeck E. A. De Wolf K. Dziunikowska A. M. F. Endler A. Eskreys Z. C. Garutchava P. van Hal T. Haupt A. I. Katargin W. Kittel S. S. Megrabyan F. Meijers A. B. Micha?owska V. I. Nikolaenko K. Olkiewicz V. M. Ronjin R. Rosmalen H. M. T. Saarikko L. Scholten E. K. Shabalina J. Stepaniak O. G. Tchikilev V. A. Uvarov F. Verbeure R. Wischnewski S. A. Zotkin Y. V. Yarba EHS-NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1990,46(3):387-395
We report on a study of ρ0, ρ+, ω, \(\bar K^{*0} (892)\) andK *0 (892) inclusive production in π+ p interactions at 250 GeV/c, for ρ+, \(\bar K^{*0} (892)\) for the first time in a π+ p experiment. The data are compared withK + p data in the same experiment, with results of other experiments and with quark-parton models. Interesting differences are found between ρ+,0 and ω production. 相似文献
113.
The emission and excitation spectra of Cr3+ -doped Gd3Ga5O12 (GGG) and Gd3Sc2Ga3O12 (GSGG) are explained in the light of multisite effects. The situation is particularly complicated in the case of GSGG, where the different sites have2E energy levels near each other which overlap with the4A2 4T2 absorption bands. The spectra obtained under selective excitations are interpreted on the multisite assumption. 相似文献
114.
In this paper, a natural R
+
n+1
extension of singular integrals, i.e.,T
κ:f→K*φ
t
*t with K a standard C-Z kernel and ϕ usual one, is investigated. One of the main results is: Let (dμ, udx) ∈C1 and u-Mw, w∈A∞, then Tk is of type (Lp(udx), Lp(dμ)). As a related topic, a maximal operator
is proved to be of type
, where
, provided (dμ, udx) ∈C1 and u∈ A∞.
Supported by National Science Foundation of China 相似文献
115.
Book Review
Functional analysis and boundary-value problems: An introductory treatmentB. Dayanand Reddy: Pitman Monographs and Survey in Pure and Applied Mathematics, Longman Scientific and Technical, 1986, 333 pp., £45.00 net 相似文献116.
S. A. Goncharov A. M. Mukhamedzhanov E. A. Romanovskii G. E. Valiev I. R. Gulamov Yu. I. Denisov T. Iskhakov A. Karakhodzhaev G. K. Nie R. Yarmuchamedov V. A. Stepanenko V. Kroha 《Czechoslovak Journal of Physics》1988,38(1):12-18
The differential cross sections of tritons from the (d, t) reaction on9Be,10B and13C targets have been measured in the angular range of 5°
LAB110° with relatively small errors, 5%. The experimental data were analysed in terms of the standard DWBA using both zero-range and exact finite-range approaches. 相似文献
117.
R. E. Ansorge B. ?sman C. N. Booth L. Burow P. Carlson R. S. De Wolf B. Eckart G. Ekspong C. Fuglesang J. Gaudaen C. Geich-Gimbel B. Holl R. Hospes K. Jon-And D. P. Johnson F. Lotse N. Manthos D. J. Munday J. E. V. Ovens W. Pelzer J. G. Rushbrooke F. Triantis L. Van hamme C. Walck C. P. Ward D. R. Ward C. J. S. Webber T. O. White G. Wilquet N. Yamdagni UA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,41(2):179-190
A detailed analysis ofK s 0 production in \(\bar pp\) |<2.5 the average transverse momentum is found to be 0.53±0.07 GeV/c at 200 GeV and 0.62±0.08 GeV/c at 900 GeV, which is an increase with respect to data at c.m. energies below 60 GeV. TheK s 0 production cross sections in inelastic collisions are 29±4 mb at 200 GeV and 63±6 mb at 900 GeV, showing an increase compared to lower energy data. The central kaon density is found to increase as a logarithmic function of energy. At 900 GeV, where statistics are sufficient to allow one to draw conclusions, the average transverse momentum is higher in events with large charged multiplicity than in events with low multiplicity. 相似文献
118.
M. Adamus N. M. Agababyan I. V. Ajinenko Yu. A. Belokopytov H. Bia?kowska H. B?ttcher P. V. Chliapnikov F. Crijns A. De Roeck E. A. De Wolf K. Dziunikowska A. M. F. Endler W. Friebel H. Graessler P. van Hal J. K. Karamyan D. Kisielewska W. Kittel A. I. Kurnosenko B. B. Levchenko F. Meijers M. Merk A. B. Micha?owska V. I. Nikolaenko L. C. S. Oliveira K. Olkiewicz V. M. Ronjin A. M. Rybin H. M. T. Saarikko Y. T. M. Saarikko W. Schmitz L. Scholten N. A. Sotnikova J. Stepaniak O. G. Tchikilev L. A. Tikhonova V. A. Uvarov F. Verbeure R. Wischnewski EHS/NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1988,37(2):215-229
The charged particle multiplicity distribution has been studied for non-single-diffractive π+ p andpp collisions at \(\sqrt s = 22\) GeV, for full phase space as well as for intervals in rapidity, azimuthal angle and transverse momentum. In general, the multiplicity distribution is well described by a negative binomial. From comparison of the distribution for negative or positive particles to that of all charged particles, cascading is favoured as an interpretation over stimulated emission. Interesting consequences follow from a comparison of our results to those at collider energies and toe + e ? data at comparable energy. Furthermore, evidence is given that the multiplicity distribution is not exactly of negative binomial type in every (connected or disconnected) phase space region. 相似文献
119.
G. Rauprich H. J. Hähn M. Karus P. Nießen K. R. Nyga H. Oswald L. Sydow H. Paetz gen Schieck Y. Koike 《Few-Body Systems》1988,5(2):67-77
The
elastic scattering was investigated especially in the Coulomb sensitive scattering regions. Angular distributions of the differential cross section and of the analyzing powerA
y, with emphasis on small scattering angles, were measured at 10.0 and 14.1 MeV. For extreme backward angles up toJ
c.m.=179° the differential cross section was measured at 12.0, 14.1 and 16.5 MeV. The data have been compared with recent Faddeev calculations based on the realistic meson-exchange Paris potential and including an approximate Coulomb correction. There are discrepancies between the data and the calculations especially for the analyzing power. This indicates that the approximate treatment of Coulomb effects and possibly also the purely nuclear part of the calculations need to be improved. 相似文献
120.
V. V. Aivazyan I. V. Ajinenko Yu. A. Belokopytov P. C. Bosetti H. B?ttcher F. Botterweck P. V. Chliapnikov F. Crijns A. De Roeck E. A. De Wolf Th. Driever K. Dziunikowska A. Eskreys W. Friebel Z. C. Garutchava V. G. Gavrjusev H. Graessler P. van Hal T. Haupt W. Kittel S. S. Megrabyan F. Meijers A. B. Micha?owska V. I. Nikolaenko L. C. S. Oliveira K. Olkiewicz L. P. Petrovikh E. Riipinen V. M. Ronjin A. M. Rybin H. M. T. Saarikko W. Schmitz L. Scholten R. Schulte O. G. Tchikilev L. A. Tikhonova A. G. Tomaradze V. A. Uvarov F. Verbeure R. Wischnewski A. Wróblewski S. A. Zotkin NA Collaboration 《Zeitschrift fur Physik C Particles and Fields》1989,42(4):533-542
Forward-backward multiplicity correlations in σ+,K + p andpp collisions at 250 GeV/c ( \(\sqrt s \) =22 GeV) are given for all charges and for the different charge combinations. The correlations are found to be caused predominantly by centrally produced particles. It is demonstrated that this result is an agreement with observations at the ISR and the CERNp \(\bar p\) -Collider. The results are compared to expectations from LUND, DPM and FRITIOF Monte Carlo models and a geometrical picture relating correlations in hadron-hadron collisions toe + e ? data in terms of impact parameters is tested. 相似文献