全文获取类型
收费全文 | 722篇 |
免费 | 16篇 |
国内免费 | 3篇 |
专业分类
化学 | 467篇 |
晶体学 | 5篇 |
力学 | 42篇 |
数学 | 88篇 |
物理学 | 139篇 |
出版年
2023年 | 8篇 |
2022年 | 26篇 |
2021年 | 20篇 |
2020年 | 15篇 |
2019年 | 13篇 |
2018年 | 16篇 |
2017年 | 5篇 |
2016年 | 25篇 |
2015年 | 23篇 |
2014年 | 23篇 |
2013年 | 37篇 |
2012年 | 59篇 |
2011年 | 63篇 |
2010年 | 40篇 |
2009年 | 35篇 |
2008年 | 43篇 |
2007年 | 51篇 |
2006年 | 37篇 |
2005年 | 50篇 |
2004年 | 26篇 |
2003年 | 25篇 |
2002年 | 31篇 |
2001年 | 3篇 |
2000年 | 6篇 |
1999年 | 2篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 8篇 |
1995年 | 3篇 |
1994年 | 4篇 |
1992年 | 3篇 |
1991年 | 1篇 |
1990年 | 3篇 |
1988年 | 3篇 |
1987年 | 3篇 |
1986年 | 4篇 |
1985年 | 3篇 |
1984年 | 2篇 |
1982年 | 1篇 |
1981年 | 1篇 |
1979年 | 2篇 |
1976年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1968年 | 1篇 |
1967年 | 1篇 |
1966年 | 1篇 |
1915年 | 1篇 |
排序方式: 共有741条查询结果,搜索用时 15 毫秒
731.
Hanessian S Papeo G Angiolini M Fettis K Beretta M Munro A 《The Journal of organic chemistry》2003,68(19):7204-7218
Alkylation of the monoenolate of N-Boc-l-pyroglutamic acid methyl ester with a variety of benzylic halides and their homologues gave the corresponding anti-C-4-alkylated products as major products. Formation of the N-Boc-iminium ion and Friedel-Crafts intramolecular cationic ring closure afforded a series of fused 1-azacyclodihydroindene derivatives with interesting topologies. Functional diversity was introduced via further manipulation of pendant groups on the original proline motif as well as on the aromatic moiety. 相似文献
732.
An ab initio quantum-classical mixed scheme for the time evolution of electrode-device-electrode systems is introduced to study nuclear dynamics in quantum transport. Two model systems are discussed to illustrate the method. Our results provide the first example of current-induced molecular desorption as obtained from a full time-dependent approach and suggest the use of ac biases as a way to tailor electromigration. They also show the importance of nonadiabatic effects for ultrafast phenomena in nanodevices. 相似文献
733.
Eleonora Marcucci Gianluca Martelli Mario Orena Samuele Rinaldi 《Monatshefte für Chemie / Chemical Monthly》2007,138(1):27-33
Summary. In the presence of DABCO, ethyl glyoxalate and (4S,5R)-1,5-dimethyl-3-acryloyl-4-phenylimidazolidin-2-one gave mixtures of the corresponding Baylis-Hillman adducts enriched in either isomer, depending on the absence or the presence of LiClO4 in the reaction mixture. A diastereomeric mixture in 10:90 dr allowed to definitively establish the mechanism of the reaction leading to trichloroacetamides starting from trichloroacetimidates
of the Baylis-Hillman adducts. 相似文献
734.
Gianluca Garello 《偏微分方程通讯》2013,38(5-6):791-801
The author studies the action of a new selfadjoint algebra of pseudodifferential operators of type (1,1) on Sobolev wave front sets for distributions. 相似文献
735.
Sébastien Boucksom Amaël Broustet Gianluca Pacienza 《Mathematische Zeitschrift》2013,275(1-2):499-507
We explain how to deduce from recent results in the Minimal Model Program a general uniruledness theorem for base loci of adjoint divisors. As a special case, we recover previous results by Takayama. 相似文献
736.
737.
Dr. Gianluigi Albano Dr. Francesco Zinna Francesco Urraci Prof. Maria Annunziata M. Capozzi Prof. Gennaro Pescitelli Prof. Angela Punzi Prof. Lorenzo Di Bari Prof. Gianluca M. Farinola 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(51):e202201178
The chiroptical features of chiral diketopyrrolo[3,4-c]pyrrole (DPP) derivatives have been only marginally investigated to date. In this regard, we have synthesized ad hoc four chiral DPP dyes, functionalized with enantiopure alkyl groups from natural sources either on the lactam moieties or on the terminal positions of the π-conjugated backbone, to promote an efficient self-assembly into chiral supramolecular structures. For each of them, the aggregation modes has been investigated by absorbance and ECD spectroscopies in conditions of solution aggregation and on thin films, considering the effects of deposition technique (drop casting vs. spin coating) and post-deposition operations (solvent and thermal annealing). The effect of the structure of lateral π-conjugated units attached to the central DPP scaffold, as well as that of the position of the alkyl chiral group, has been assessed. ECD revealed superior capability, compared to absorbance spectroscopy, to provide information on the aggregation modes and to detect the possible co-existence of multiple aggregation pathways. 相似文献
738.
Garcia-Pozuelo Daniel Olatunbosun Oluremi Palli Gianluca Strano Salvatore Terzo Mario Tordela Ciro 《Meccanica》2022,57(8):1801-1829
Meccanica - The employment of intelligent tires to test the vehicle performances is ever-increasing in the last years. Many research activities have been made to correlate measurements provided by... 相似文献
739.
Here, we provide a unifying treatment of the convergence of a general form of sampling-type operators, given by the so-called sampling Durrmeyer-type series. The main result consists of the study of a modular convergence theorem in the general setting of Orlicz spaces . From the latter theorem, the convergence in , in , and in the exponential spaces can be obtained as particular cases. For the completeness of the theory, we provide a pointwise and uniform convergence theorem on , in case of bounded continuous and bounded uniformly continuous functions; in this context, we also furnish a quantitative estimate for the order of approximation, using the modulus of continuity of the function to be approximated. Finally, applications and examples with graphical representations are given for several sampling series with special kernels. 相似文献
740.