全文获取类型
收费全文 | 345篇 |
免费 | 29篇 |
专业分类
化学 | 296篇 |
晶体学 | 1篇 |
力学 | 4篇 |
数学 | 30篇 |
物理学 | 43篇 |
出版年
2024年 | 1篇 |
2023年 | 2篇 |
2022年 | 6篇 |
2021年 | 6篇 |
2020年 | 10篇 |
2019年 | 6篇 |
2017年 | 2篇 |
2016年 | 26篇 |
2015年 | 17篇 |
2014年 | 20篇 |
2013年 | 25篇 |
2012年 | 22篇 |
2011年 | 24篇 |
2010年 | 23篇 |
2009年 | 8篇 |
2008年 | 30篇 |
2007年 | 18篇 |
2006年 | 17篇 |
2005年 | 15篇 |
2004年 | 14篇 |
2003年 | 5篇 |
2002年 | 5篇 |
2001年 | 4篇 |
2000年 | 2篇 |
1999年 | 5篇 |
1997年 | 1篇 |
1995年 | 1篇 |
1994年 | 3篇 |
1993年 | 6篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1985年 | 3篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 8篇 |
1976年 | 2篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1971年 | 1篇 |
1966年 | 4篇 |
1964年 | 1篇 |
1950年 | 1篇 |
1948年 | 4篇 |
1947年 | 6篇 |
1946年 | 3篇 |
1933年 | 2篇 |
1925年 | 1篇 |
1923年 | 1篇 |
1920年 | 1篇 |
排序方式: 共有374条查询结果,搜索用时 0 毫秒
31.
32.
Franziska Doll Annette Buntz Anne‐Katrin Späte Verena F. Schart Alexander Timper Waldemar Schrimpf Prof. Dr. Christof R. Hauck Prof. Dr. Andreas Zumbusch Prof. Dr. Valentin Wittmann 《Angewandte Chemie (International ed. in English)》2016,55(6):2262-2266
Protein glycosylation is a ubiquitous post‐translational modification that is involved in the regulation of many aspects of protein function. In order to uncover the biological roles of this modification, imaging the glycosylation state of specific proteins within living cells would be of fundamental importance. To date, however, this has not been achieved. Herein, we demonstrate protein‐specific detection of the glycosylation of the intracellular proteins OGT, Foxo1, p53, and Akt1 in living cells. Our generally applicable approach relies on Diels–Alder chemistry to fluorescently label intracellular carbohydrates through metabolic engineering. The target proteins are tagged with enhanced green fluorescent protein (EGFP). Förster resonance energy transfer (FRET) between the EGFP and the glycan‐anchored fluorophore is detected with high contrast even in presence of a large excess of acceptor fluorophores by fluorescence lifetime imaging microscopy (FLIM). 相似文献
33.
34.
Various substituted dibenzo[b,f][1,4]oxazepines underwent an enantioselective alkylation with Et2Zn catalyzed by a (R)-VAPOL-Zn(II) complex. The corresponding chiral 11-ethyl-10,11-dihydrodibenzo[b,f][1,4]oxazepine derivatives were obtained with good yields and moderate enantioselectivities. This represents the first example of enantioselective addition of Et2Zn to cyclic aldimines. 相似文献
35.
36.
Michael Müller Prof. Dr. Markus Albrecht Verena Gossen Tanja Peters Andreas Hoffmann Prof. Dr. Gerhard Raabe Dr. Arto Valkonen Prof. Kari Rissanen 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(41):12446-12453
The directionality of interaction of electron‐deficient π systems with spherical anions (e.g,. halides) can be controlled by secondary effects like NH or CH hydrogen bonding. In this study a series of pentafluorophenyl‐substituted salts with polyhalide anions is investigated. The compounds are obtained by aerobic oxidation of the corresponding halide upon crystallization. Solid‐state structures reveal that in bromide 2 , directing NH–anion interactions position the bromide ion in an η1‐type fashion over but not in the center of the aromatic ring. The same directing forces are effective in corresponding tribromide salt 3 . In the crystal, the bromide ion is paneled by four electron‐deficient aromatic ring systems. In addition, compounds 4 and 6 , which have triiodide and the rare tetraiodide dianion as anions, are described. Computational studies reveal that the latter is highly unstable. In the present case it is stabilized by the crystal lattice, for example, by interaction with electron‐deficient π systems. 相似文献
37.
Syntheses and Crystal Structures of Rb4Br2O and Rb6Br4O In the quasi‐binary system RbBr/Rb2O, the addition compounds Rb4Br2O and Rb6Br4O are obtained by solid state reaction of the boundary components RbBr and Rb2O. Crystals of red‐orange Rb4Br2O as well as of orange Rb6Br4O decompose immediately when exposed to air. Rb4Br2O (Pearson code tI14, I4/mmm, a = 544.4(6) pm, c = 1725(2) pm, Z = 2, 175 symmetry independent reflections with Io > 2σ(I), R1= 0.0618) crystallizes in the anti K2NiF4 structure type; Rb6Br4O (Pearson code hR22, R3c, a = 1307.8(3) pm, c = 1646.6(5) pm, Z = 6, 630 symmetry independent reflections with Io > 2σ(I), R1 = 0.0759) in the anti K4CdCl6 structure type. Both structures contain characteristic ORb6‐octahedra and can be understood as expanded perovskites, following the general systematics of alkaline metal oxide halides. 相似文献
38.
39.
40.
Kerstin T. Wiss Patrick Theato 《Journal of polymer science. Part A, Polymer chemistry》2010,48(21):4758-4767
The synthesis of block copolymers via polymer conjugation of well‐defined building blocks offers excellent control over the structures obtained, but often several coupling strategies need to be explored to find an efficient one depending on the building blocks. To facilitate the synthesis of polymers with adjustable functional end‐groups for polymer conjugation, we report on the combination of activated ester chemistry with RAFT polymerization using a chain transfer agent (CTA) with a pentafluorophenyl ester (PFP‐CTA), which allows for flexible functionalization of either the CTA prior to polymerization or the obtained polymer after polymerization. Different polymethacrylates, namely PMMA, P(t‐BuMA) and PDEGMEMA, were synthesized with an alkyne‐CTA obtained from the aminolysis of the PFP‐CTA with propargylamine, and the successful incorporation of the alkyne moiety could be shown via 1H and 13C NMR spectroscopy and MALDI TOF MS. Further, the reactive α‐end‐groups of polymers synthesized using the unmodified PFP‐CTA could be converted into azide and alkyne end‐groups after polymerization, and the high functionalization efficiencies could be demonstrated via successful coupling of the resulting polymers via CuAAC. Thus, the PFP‐CTA allows for high combinatory flexibility in polymer synthesis facilitating polymer conjugation as useful method for the synthesis of block copolymers. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010 相似文献