全文获取类型
收费全文 | 347篇 |
免费 | 14篇 |
国内免费 | 3篇 |
专业分类
化学 | 271篇 |
晶体学 | 2篇 |
力学 | 4篇 |
数学 | 36篇 |
物理学 | 51篇 |
出版年
2023年 | 3篇 |
2022年 | 12篇 |
2021年 | 11篇 |
2020年 | 7篇 |
2019年 | 11篇 |
2018年 | 7篇 |
2017年 | 6篇 |
2016年 | 11篇 |
2015年 | 16篇 |
2014年 | 8篇 |
2013年 | 29篇 |
2012年 | 26篇 |
2011年 | 30篇 |
2010年 | 18篇 |
2009年 | 24篇 |
2008年 | 20篇 |
2007年 | 15篇 |
2006年 | 21篇 |
2005年 | 13篇 |
2004年 | 6篇 |
2003年 | 8篇 |
2002年 | 9篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 4篇 |
1997年 | 1篇 |
1996年 | 4篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1989年 | 2篇 |
1988年 | 2篇 |
1987年 | 3篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1966年 | 1篇 |
1948年 | 1篇 |
1936年 | 2篇 |
1934年 | 1篇 |
1926年 | 1篇 |
1917年 | 3篇 |
排序方式: 共有364条查询结果,搜索用时 15 毫秒
31.
Alberto García Nora Bretón Isidore Hauser 《International Journal of Theoretical Physics》1988,27(5):635-640
It is shown that any stationary axisymmetric solution to the vacuum field equations of the Jordan-Brans-Dicke (JBD) theory may be obtained from a composition of any stationary axisymmetric vacuum Einstein spacetime with the Weyl class of metrics. Thus, generating solution techniques can be used to obtain any stationary axisymmetric JBD vacuum solution. In this manner, C. B. G. McIntosh's results concerning this topic are improved upon. 相似文献
32.
33.
34.
35.
2‐Aminoacetophenone (AAP) was recognized as the key compound for the so‐called untypical aging off‐flavor (UTA) in Vitis vinifera wines. In this study, it was shown that AAP can be formed by photooxidation of free and protein‐bound tryptophan (TRP) in combination with a subsequent storage in model wine. Solutions of TRP and lysozyme were exposed to artificial sunlight both in the presence and in the absence of the photosensitizer riboflavin. Aliquots of the irradiation batches were stored in model wine solutions containing tartaric acid, sulfite and ethanol in different combinations. AAP formation could be identified from both free and bound (lysozyme) TRP, while free TRP resulted in higher yields. The presence of riboflavin during irradiation generally favored the AAP formation. AAP formation increased with increasing irradiation times, but AAP was not detectable, if TRP was directly incubated in model wine. Not only the irradiation time but also the storage time of model wines favored the formation of AAP. Concerning the model wine composition, it became evident that the presence of tartaric acid resulted in the highest AAP formation during storage. 相似文献
36.
Pauwels N Aspeslagh S Vanhoenacker G Sandra K Yu ED Zajonc DM Elewaut D Linclau B Van Calenbergh S 《Organic & biomolecular chemistry》2011,9(24):8413-8421
A synthetic approach is presented for the synthesis of galacturonic acid and D-fucosyl modified KRN7000. The approach allows for late-stage functionalisation of both the sugar 6'-OH and the sphingosine amino groups, which enables convenient synthesis of promising 6'-modified KRN7000 analogues. 相似文献
37.
Ohne Zusammenfassung 相似文献
38.
Raúl Comelli Zunilda Finelli Sergio Canavese Nora Fígoli 《Reaction Kinetics and Catalysis Letters》1995,55(1):171-181
The effect of Mg addition to Pd impregnated silica-alumina catalysts and the behavior of these catalysts in synthesis gas to hydrocarbons transformation have been studied. Measurements of H2 chemisorption and temperature programmed NH3 desorption allow us to consider that Mg addition to Pd containing catalysts increases the Pd dispersity, the support acidity not being modified. The presence of Mg enhances hydrocarbon production. Meanwhile, the hydrocarbon distribution is not modified. A large amount of light alkanes in the reaction products is obtained. 相似文献
39.
40.
An inexpensive ruthenium catalyst enabled oxidative annulations of alkynes by acrylamides with ample scope, which allowed for the preparation of 2-pyridones employing various electron-rich and electron-deficient acrylamides as well as (di)aryl- and (di)alkyl-substituted alkynes. 相似文献