全文获取类型
收费全文 | 128篇 |
免费 | 6篇 |
国内免费 | 1篇 |
专业分类
化学 | 65篇 |
力学 | 2篇 |
数学 | 36篇 |
物理学 | 32篇 |
出版年
2022年 | 2篇 |
2021年 | 2篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2017年 | 3篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 6篇 |
2013年 | 5篇 |
2011年 | 5篇 |
2010年 | 4篇 |
2009年 | 4篇 |
2007年 | 2篇 |
2006年 | 7篇 |
2005年 | 6篇 |
2004年 | 3篇 |
2003年 | 2篇 |
2002年 | 3篇 |
2001年 | 2篇 |
2000年 | 2篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 2篇 |
1992年 | 1篇 |
1989年 | 3篇 |
1988年 | 4篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1982年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 1篇 |
1977年 | 3篇 |
1976年 | 2篇 |
1975年 | 2篇 |
1973年 | 1篇 |
1971年 | 2篇 |
1970年 | 2篇 |
1969年 | 1篇 |
1968年 | 1篇 |
1967年 | 2篇 |
1966年 | 2篇 |
1943年 | 1篇 |
1935年 | 2篇 |
1933年 | 2篇 |
1932年 | 1篇 |
1931年 | 2篇 |
排序方式: 共有135条查询结果,搜索用时 31 毫秒
131.
A. K. Wick 《Helvetica chimica acta》1971,54(3):769-782
The behaviour of di-(1-anthraquinonyl)-amine, when cyclised in pyridine-aluminium chloride or pure aluminium chloride fusions, has been compared. The formation of blue educt complexes with aluminium chloride in the latter case has been revealed as a factor which inhibits cyclisation. The results are discussed and generalised, classifying carbazolation of anthrimides as an intramolecular Scholl-type reaction. 相似文献
132.
First principles DFT calculations are used to gain insights into the molecular mechanism of Cr passivation of FeCr alloy surfaces. The systems studied represent early stages of oxidation of FeCr alloys when the oxide layers extend just a few atomic layers into the bulk. A Monte-Carlo atom-swapping algorithm was developed to efficiently explore possible atomic positions and identify the most promising structures that yield overall energy lowering. Analysis of the resulting low energy structures show that the surface oxide layer is rich in chromium while there is a reduction in chromium in the metallic phase near the alloy-oxide interface. Furthermore, there is an increased concentration of Fe near the oxide-air surface. Analysis of the molecular structure of the oxide layers found that oxidized Cr was predominantly in the Cr2O3 phase, while oxidized Fe was present as both FeO and Fe2O3. We propose that the oxidative variability of Fe facilitates O diffusion in the iron-rich phases because of the range of geometries available for accommodating the O atom. In contrast, O diffusion is less facile in Cr, which has little variability in oxidation state. 相似文献
133.
Nanotoxicology: an interdisciplinary challenge 总被引:1,自引:0,他引:1
The increasing consumption of products containing nanomaterials that can be currently observed and forecasts of new developments and applications fan the fear of individuals and organizations regarding new risks to health. Considering experiences gained from previous technology developments, such fears are not completely unfounded. But are they really justified? And is it justified, moreover, to speak of “nanotoxicology” as a new discipline? This Review seeks to cast light on the phenomena that may occur as nanoobjects interact with cells, tissues, and organisms. Furthermore, we will demonstrate that the many data made available on the biological effects of nanomaterials do not always come from studies that can be considered reliable. We will point out the aspect of reliability with specific examples from the literature and will not address specific (nano)materials. In particular, inadequate methods will be described together with recommendations how to avoid this in the future, thereby contributing to a sustainable improvement of the available data. 相似文献
134.
We provide a new proof of Volberg’s Theorem characterizing thin interpolating sequences as those for which the Gram matrix associated to the normalized reproducing kernels is a compact perturbation of the identity. In the same paper, Volberg characterized sequences for which the Gram matrix is a compact perturbation of a unitary as well as those for which the Gram matrix is a Schatten-2 class perturbation of a unitary operator. We extend this characterization from 2 to p, where 2 ≤ p ≤ ∞. 相似文献
135.
Journal of Fourier Analysis and Applications - The purpose of this article is to provide an alternative proof of the weak-type $$\left( 1,\ldots ,1;\frac{1}{m}\right) $$ estimate for m-multilinear... 相似文献