全文获取类型
收费全文 | 13855篇 |
免费 | 346篇 |
国内免费 | 5篇 |
专业分类
化学 | 7059篇 |
晶体学 | 155篇 |
力学 | 286篇 |
数学 | 2784篇 |
物理学 | 3922篇 |
出版年
2022年 | 146篇 |
2021年 | 198篇 |
2020年 | 184篇 |
2019年 | 192篇 |
2018年 | 229篇 |
2017年 | 225篇 |
2016年 | 488篇 |
2015年 | 453篇 |
2014年 | 494篇 |
2013年 | 957篇 |
2012年 | 640篇 |
2011年 | 715篇 |
2010年 | 503篇 |
2009年 | 435篇 |
2008年 | 427篇 |
2007年 | 374篇 |
2006年 | 324篇 |
2005年 | 189篇 |
2004年 | 222篇 |
2003年 | 225篇 |
2002年 | 232篇 |
2001年 | 184篇 |
2000年 | 225篇 |
1999年 | 190篇 |
1998年 | 179篇 |
1997年 | 167篇 |
1996年 | 168篇 |
1995年 | 160篇 |
1994年 | 154篇 |
1993年 | 164篇 |
1992年 | 153篇 |
1991年 | 139篇 |
1990年 | 152篇 |
1989年 | 133篇 |
1988年 | 144篇 |
1987年 | 145篇 |
1986年 | 120篇 |
1985年 | 181篇 |
1984年 | 187篇 |
1983年 | 133篇 |
1982年 | 156篇 |
1981年 | 150篇 |
1980年 | 151篇 |
1979年 | 161篇 |
1978年 | 152篇 |
1977年 | 144篇 |
1976年 | 162篇 |
1975年 | 168篇 |
1974年 | 155篇 |
1965年 | 116篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Palladium and molybdenum polycrystalline layers (clusters) have been deposited in a stainless steel UHV system onto a layer of alumina (Al2O3). This layer has been prepared by high temperature oxidation of an aluminium layer. The interaction of this system with nitrogen has been investigated at room temperature by an FEM technique. Under these conditions nitrogen spillover from molybdenum to palladium has been observed. 相似文献
2.
3.
4.
Lubomír Kubáček 《Applications of Mathematics》2006,51(6):565-582
Some remarks to problems of point and interval estimation, testing and problems of outliers are presented in the case of multivariate
regression model.
This work was supported by the Council of Czech Government J14/98:153100011. 相似文献
5.
6.
V. Balek T. Mitsuhashi I.M. Bountseva H. Haneda Z. Malek J. Šubrt 《Journal of Sol-Gel Science and Technology》2003,26(1-3):185-189
The diffusion structural analysis (DSA) was used to characterize microstructure changes of hydrous titania gel films under in situ conditions of heating. TG and DTA were used in order to elucidate the processes controlling the formation of anatase film during heating of hydrous titania gel film. The annealing of porosity and near surface structure defects of the dehydrated titania films was indicated by DSA in the temperature range 255–700°C as the decrease of radon release rate. It was demonstrated that the annealing was enhanced on heating in oxygen in comparison with heating in argon. The DSA experimental results were compared with model curves describing the radon diffusion mobility and the annealing of radon diffusion paths. 相似文献
7.
Harnack inequality for some classes of Markov processes 总被引:3,自引:0,他引:3
In this paper we establish a Harnack inequality for nonnegative harmonic functions of some classes of Markov processes with jumps.
Mathematics Subject Classification (2000): Primary 60J45, 60J75, Secondary 60J25.This work was completed while the authors were in the Research in Pairs program at the Mathematisches Forschungsinstitut Oberwolfach. We thank the Institute for the hospitality.The research of this author is supported in part by NSF Grant DMS-9803240.The research of this author is supported in part by MZT grant 0037107 of the Republic of Croatia. 相似文献
8.
9.
We study condensation of ethanol-hexanol vapour by numerical solution of kinetic equations. The number of droplets formed
in unit volume is computed within self-consistent classical model. It is shown that formation of ethanol-rich droplets prevails
at the initial stage of nucleation process, but in the stationary state formation of droplets near the saddle point (on cluster
formation energy surface) plays the dominant role.
Presented at the 6th Joint Seminar “Development of Materials Science in Research and Education”, Karlštejn, Czech Republic,
17–19 September 1996.
This work was supported by Grant No. A1010615 of the Grant Agency of the Academy of Sciences of the Czech Republic. 相似文献
10.
Botjan Japelj Simon Re
nik Petra ebaek Branko Stanovnik Jurij Svete 《Journal of heterocyclic chemistry》2005,42(6):1167-1173
A series of alkyl l‐heteroaryl‐1H‐1,2,3‐triazole‐4‐carboxylates 6a‐u were synthesised in four steps from methyl (Z)‐2‐benzyloxycarbonylarmino‐3‐(dimethylamino)prop‐2‐enoate ( 1 ) and heterocyclic amines 2a‐s. Triazoles 6a‐o were tested against antimycobacterial activity. For the most active compound, n‐pentyl 1‐(6‐phenylpyridazin‐3‐yl)‐1H‐1,2,3‐triazole‐4‐carboxylate ( 6n ), minimum inhibitory concentration 3.13 μg/ml was determined. 相似文献