全文获取类型
收费全文 | 1265篇 |
免费 | 40篇 |
国内免费 | 8篇 |
专业分类
化学 | 912篇 |
晶体学 | 33篇 |
力学 | 28篇 |
数学 | 69篇 |
物理学 | 271篇 |
出版年
2024年 | 3篇 |
2023年 | 14篇 |
2022年 | 20篇 |
2021年 | 18篇 |
2020年 | 39篇 |
2019年 | 43篇 |
2018年 | 31篇 |
2017年 | 39篇 |
2016年 | 56篇 |
2015年 | 38篇 |
2014年 | 91篇 |
2013年 | 99篇 |
2012年 | 92篇 |
2011年 | 125篇 |
2010年 | 60篇 |
2009年 | 72篇 |
2008年 | 88篇 |
2007年 | 85篇 |
2006年 | 60篇 |
2005年 | 43篇 |
2004年 | 47篇 |
2003年 | 45篇 |
2002年 | 36篇 |
2001年 | 12篇 |
2000年 | 9篇 |
1999年 | 4篇 |
1998年 | 8篇 |
1997年 | 7篇 |
1996年 | 8篇 |
1995年 | 3篇 |
1994年 | 2篇 |
1993年 | 2篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1981年 | 1篇 |
排序方式: 共有1313条查询结果,搜索用时 15 毫秒
131.
132.
Kumar Sunil Jeon H. C. Kang T. W. Kalia Rajesh Sharma J. K. Panwar Sanjay Kalia Sapna Sharma Vandana Choubey R. K. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2017,91(13):2666-2670
Russian Journal of Physical Chemistry A - In the present work, the effect of temperature and moisture has been studied on nano-porous polycarbonate membranes of size 15, 50, and 80 nm, respectively... 相似文献
133.
134.
135.
V. V. Vinogradov A. V. Agafonov A. V. Vinogradov K. T. Pillai Rajesh V. Pai S. K. Mukerjee S. K. Aggarwal 《Journal of Sol-Gel Science and Technology》2011,60(1):6-10
Mesoporous γ-Al2O3 materials with high surface area and a narrow pore size distribution were synthesized by facile sol–gel procedure with application
of the polymer–colloid complex as a template. 相似文献
136.
Tungsten oxide thin films are of great interest due to their promising applications in various optoelectronic thin film devices. We have investigated the microstructural evolution of tungsten oxide thin films grown by DC magnetron sputtering on silicon substrate. The structural characterization and surface morphology were carried out using X-ray diffraction and Scanning Electron Microscopy (SEM). The as deposited films were amorphous, where as, the films annealed above 400 °C were crystalline. In order to explain the microstructural changes due to annealing, we have proposed a “instability wheel” model for the evolution of the microstructure. This model explains the transformation of mater into various geometries within them selves, followed by external perturbation. 相似文献
137.
Radon exhalation rate from fly ash samples and from the homogeneous mixture of fly ash of different proportions additive in soil and cement samples to study the effect of the addition was measured by cup dosimeter using SSNTDs. Radon activities were found to vary from (1018±38) to ( whereas the radon exhalation rate varied from (366±14) to . A gradual increase has been observed in samples having fly ash as an additive in cement samples whereas a gradual decrease was observed in soil samples after the addition of fly ash. 238U in fly ash was measured by a low-level NaI (Tl)-based gamma ray spectrometer. The results show enhancement in U concentration in fly ash as compared to coal samples, whereas radon exhalation rate is less in fly ash samples. 相似文献
138.
A series of three new mononucleating thiosemicarbazone ligands possessing potential S, N, and O coordination sites have been
prepared by the reaction of 2-formylphenoxy acetic acid with substituted thiosemicarbazides. Complexes of these ligands with
CoII, NiII, CuII, and ZnII have prepared and characterized by physico-chemical and spectroscopic methods. In all the complexes, the dibasic tetradentate
nature of the ligand is evident. 相似文献
139.
Chemical characterization of bamboo borer dust (BBD) indicated that it contained 2.5 ±0.5% of an organic entity that was a
watersoluble, acid-labile phosphate, nonreducing sugar with a retention period of 5.2 min on a sugar pack column during high
pressure liquid chromatography (HPLC). It was subsequently identified and confirmed as glucose-1-phosphate (G-l-P) from its
response to phosphoglucomutase and glucose-6-phosphatase treatment. Although the presence of G-l-P in such a large quantity
in BBD is inexplicable, it provides a rare and rich source of G-l-P, making it a potential starting material for its isolation
in pure state. 相似文献
140.
Rajesh Pereira 《Linear algebra and its applications》2007,421(1):117-121
We explore the use of the weak log-majorization order in the analytic theory of polynomials. We examine the relationship between weak log-majorization and Mahler measure. We also improve the weak log-majorization form of the de Bruijn-Springer-Mahler inequality. 相似文献