全文获取类型
收费全文 | 1172篇 |
免费 | 39篇 |
国内免费 | 2篇 |
专业分类
化学 | 793篇 |
晶体学 | 33篇 |
力学 | 20篇 |
数学 | 67篇 |
物理学 | 300篇 |
出版年
2021年 | 7篇 |
2019年 | 15篇 |
2018年 | 10篇 |
2017年 | 8篇 |
2016年 | 29篇 |
2015年 | 34篇 |
2014年 | 24篇 |
2013年 | 34篇 |
2012年 | 45篇 |
2011年 | 52篇 |
2010年 | 34篇 |
2009年 | 37篇 |
2008年 | 56篇 |
2007年 | 59篇 |
2006年 | 50篇 |
2005年 | 39篇 |
2004年 | 56篇 |
2003年 | 27篇 |
2002年 | 29篇 |
2001年 | 18篇 |
2000年 | 25篇 |
1999年 | 9篇 |
1998年 | 14篇 |
1997年 | 19篇 |
1996年 | 21篇 |
1995年 | 22篇 |
1994年 | 21篇 |
1993年 | 19篇 |
1992年 | 19篇 |
1991年 | 20篇 |
1990年 | 17篇 |
1989年 | 25篇 |
1988年 | 22篇 |
1987年 | 22篇 |
1986年 | 14篇 |
1985年 | 15篇 |
1984年 | 16篇 |
1983年 | 8篇 |
1982年 | 11篇 |
1981年 | 13篇 |
1980年 | 15篇 |
1979年 | 9篇 |
1978年 | 17篇 |
1977年 | 19篇 |
1976年 | 10篇 |
1975年 | 13篇 |
1974年 | 7篇 |
1973年 | 10篇 |
1971年 | 7篇 |
1966年 | 6篇 |
排序方式: 共有1213条查询结果,搜索用时 15 毫秒
91.
E. Rupp G. Siebler W. Brachmann F. Lehmann B. Lokau M. Berdau W. Schmitz und A. Noll 《Fresenius' Journal of Analytical Chemistry》1925,67(10):409-411
Ohne Zusammenfassung 相似文献
92.
93.
94.
G. T. Jones R. W. L. Jones B. W. Kennedy S. W. O'Neale H. Klein D. R. O. Morrison P. Schmid H. Wachsmuth F. Hamisi D. B. Miller M. M. Mobayyen S. Wainstein M. Aderholz D. Hantke E. Hoffmann U. F. Katz J. Kern N. Schmitz W. Wittek G. Corrigan G. Myatt D. Radojicic P. N. Shotton S. J. Towers F. W. Bullock S. Burke 《Zeitschrift fur Physik C Particles and Fields》1989,44(3):379-384
Within the framework of the quark-parton model, the quark and anti-quark structure functions of the proton have been measured by fitting them to the distributions of the events in the Bjorkeny variable. The data used form the largest sample of neutrino and antineutrino interactions on a pure hydrogen target available, and come from exposures of BEBC to the CERN wide band neutrino and antineutrino beams. It is found that the ratiod v /u v of valence quark distributions falls with increasing Bjorkenx. In the context of the quark-parton model the results constrain the isospin composition of the accompanying diquark system. Models involving scattering from diquarks are in disagreement with the data. 相似文献
95.
E. A. Mitscherlich H. Fischer L. T. Bowser A. Strigel J. Dodt und B. Schmitz 《Fresenius' Journal of Analytical Chemistry》1913,52(9):587-590
Ohne Zusammenfassung 相似文献
96.
On the Crystal Chemistry of Some Alkali Thiomanganates and -zincates. With a Remark on the ThCr2Si2-Type New quaternary sulfides ALiMS2 (A ? K, Rb, Cs and M ? Mn, Zn) were synthesized by a reaction of alkali carbonates with manganese and zinc, respectively, in a stream of H2S at 800°C. Single crystal X-ray investigations revealed the structures of KLiMnS2 and KLiZnS2. All compounds are isotypic and crystallize in the BaZn2P2-structure type. The atomic arrangements are treated as nine spheres close packings of sulfur atoms filled with cations. Criteria are given to distinguish the BaZn2P2-structure type from the ThCr2Si2-structure type. 相似文献
97.
Simone Portmann Hiu Ying Kwan Regula Theurillat Andrea Schmitz Meike Mevissen Wolfgang Thormann 《Journal of chromatography. A》2010,1217(51):7942-7948
Ketamine, a phencyclidine derivative, is used for induction of anesthesia, as an anesthetic drug for short term surgical interventions and in subanesthetic doses for postoperative pain relief. Ketamine undergoes extensive hepatic first-pass metabolism. Enantioselective capillary electrophoresis with multiple isomer sulfated β-cyclodextrin as chiral selector was used to identify cytochrome P450 enzymes involved in hepatic ketamine and norketamine biotransformation in vitro. The N-demethylation of ketamine to norketamine and subsequently the biotransformation of norketamine to other metabolites were studied via analysis of alkaline extracts of in vitro incubations of racemic ketamine and racemic norketamine with nine recombinantly expressed human cytochrome P450 enzymes and human liver microsomes. Norketamine was formed by CYP3A4, CYP2C19, CYP2B6, CYP2A6, CYP2D6 and CYP2C9, whereas CYP2B6 and CYP2A6 were identified to be the only enzymes which enable the hydroxylation of norketamine. The latter two enzymes produced metabolic patterns similar to those found in incubations with human liver microsomes. The kinetic data of ketamine N-demethylation with CYP3A4 and CYP2B6 were best described with the Michaelis–Menten model and the Hill equation, respectively. This is the first study elucidating the individual enzymes responsible for hydroxylation of norketamine. The obtained data suggest that in vitro biotransformation of ketamine and norketamine is stereoselective. 相似文献
98.
K. Kadija N. Schmitz P. Seyboth 《The European Physical Journal C - Particles and Fields》2011,71(1):239-241
A model for antiproton production in nucleon-nucleus and nucleus-nucleus collisions at 200 GeV per nucleon, based on the Wounded Nucleon Model is developed. The predictions are compared to published nucleon-nucleus and sulphur-nucleus data. The results suggest the presence of similar antiproton production processes in nucleon-nucleus and nucleus-nucleus collisions near midrapidity. 相似文献
99.
Willers T Cezar JC Brookes NB Hu Z Strigari F Körner P Hollmann N Schmitz D Bianchi A Fisk Z Tanaka A Tjeng LH Severing A 《Physical review letters》2011,107(23):236402
We have been able to induce a linear dichroic signal in the Yb M(5) x-ray absorption white line of cubic YbInNi(4) by the application of a magnetic field. The nonzero integrated intensity of the magnetic field induced dichroic spectrum indicates a net noncubic 4f orbital polarization. A quantitative analysis of the temperature and field strength dependence establishes that the crystal-field ground state is a Γ(8) quartet. The results demonstrate the potential of magnetic field induced linear dichroism as a new powerful approach for the investigation of the degeneracy and orbital degrees of freedom of cubic heavy-fermion and Kondo systems. 相似文献
100.