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排序方式: 共有236条查询结果,搜索用时 15 毫秒
91.
J. Muter L. de Koningh N. J. Lane A. von Asboth F. Wallenstein H. Finck E. von Raumer H. Schlegel F. Voigtländer A. Lidoff E. Twitchell K. Farnsteiner Brunner G. Halphen D. Wesson A. Ssabanejew M. Saytzeff C. Saytzeff A. Saytzeff A. C. Geitel O. Hehner C. A. Mitchell B. Stahmer F. Krafft C. Hell Chr Jordanoff K. Hazura A. Friedreich A. Grüssner R. Benedikt D. Kurbatoff und E. Ljubarsky 《Fresenius' Journal of Analytical Chemistry》1900,39(3):167-183
Ohne Zusammenfassung 相似文献
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Unsymmetrical monohydroxypentaalkoxytriphenylenes have been conveniently prepared from the readily accessible symmetrical hexa-alkyloxytriphenylenes using boron tribromide mediated ether cleavage. 相似文献
94.
Gyuzel Yu. Mitronova Dr. Vladimir N. Belov Dr. Mariano L. Bossi Dr. Christian A. Wurm Dr. Lars Meyer Dr. Rebecca Medda Dr. Gael Moneron Dr. Stefan Bretschneider Dr. Christian Eggeling Dr. Stefan Jakobs Dr. Stefan W. Hell Prof. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(15):4477-4488
New photostable rhodamine dyes represented by the compounds 1 a – r and 3 – 5 are proposed as efficient fluorescent markers with unique combination of structural features. Unlike rhodamines with monoalkylated nitrogen atoms, N′,N‐bis(2,2,2‐trifluoroethyl) derivatives 1 e , 1 i , 1 j , 3 ‐H and 5 were found to undergo sulfonation of the xanthene fragment at the positions 4′ and 5′. Two fluorine atoms were introduced into the positions 2′ and 7′ of the 3′,6′‐diaminoxanthene fragment in compounds 1 a – d , 1 i – l and 1 m – r . The new rhodamine dyes may be excited with λ=488 or 514 nm light; most of them emit light at λ=512–554 nm (compounds 1 q and 1r at λ=576 and 589 nm in methanol, respectively) and have high fluorescence quantum yields in solution (up to 98 %), relatively long excited‐state lifetimes (>3 ns) and are resistant against photobleaching, especially at high laser intensities, as is usually applied in confocal microscopy. Sulfonation of the xanthene fragment with 30 % SO3 in H2SO4 is compatible with the secondary amide bond (rhodamine‐CON(Me)CH2CH2COOH) formed with MeNHCH2CH2COOCH3 to providing the sterically unhindered carboxylic group required for further (bio)conjugation reactions. After creating the amino reactive sites, the modified derivatives may be used as fluorescent markers and labels for (bio)molecules in optical microscopy and nanoscopy with very‐high light intensities. Further, the new rhodamine dyes are able to pass the plasma membrane of living cells, introducing them as potential labels for recent live‐cell‐tag approaches. We exemplify the excellent performance of the fluorinated rhodamines in optical microscopy by fluorescence correlation spectroscopy (FCS) and stimulated emission depletion (STED) nanoscopy experiments. 相似文献
95.
Zoltán Baán Attila Potor Agnieszka Cwik Zoltán Hell György Keglevich Zoltán Finta 《合成通讯》2013,43(10):1601-1609
A new Pd/MgLa mixed oxide and the known Pd/MgAl hydrotalcite catalysts were applied and recycled successfully in catalytic transfer hydrogenation reactions in ionic liquids. Some α,β‐unsaturated carboxylic acid derivatives were hydrogenated in excellent yields. The catalysts were recycled without significant loss of activity. Besides that, a number of halogenated aromatic compounds were dehalogenated under similar catalytic transfer conditions. 相似文献
96.
Volker Burkart Rahel K Siegenthaler Elias Blasius Koen Vandenbroeck Iraide Alloza Waltraud Fingberg Nanette C Schloot Philipp Christen Hubert Kolb 《BMC biochemistry》2010,11(1):44
Background
Chaperones facilitate proper folding of peptides and bind to misfolded proteins as occurring during periods of cell stress. Complexes of peptides with chaperones induce peptide-directed immunity. Here we analyzed the interaction of (pre)proinsulin with the best characterized chaperone of the hsp70 family, bacterial DnaK. 相似文献97.
A novel hydroxyamino phosphane was synthesised through the reaction of 2-imidazolidinone with ClPPh2 and subsequently reaction
of the resulting bisphosphino derivative with the Grignard reagent BrMgC5H11. The interaction of the pentyl substituent with one of the two phosphino groups and the structure in solution is shown by
multinuclear NMR-spectroscopy..
相似文献
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