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排序方式: 共有685条查询结果,搜索用时 15 毫秒
681.
Mark Damen Mario A. Izidoro Debora N. Okamoto Lilian C. G. Oliveira Helene I. V. Amatdjais-Groenen Stijn F. M. van Dongen Koen W. R. van Cleef Ronald P. van Rij Cindy E. J. Dieteren Daniel Girons Bernd N. M. van Buuren Byron E. E. Martina Albert D. M. E. Osterhaus Luiz Juliano Bob J. Scholte Martin C. Feiters 《Molecules (Basel, Switzerland)》2022,27(10)
Dengue is an important arboviral infectious disease for which there is currently no specific cure. We report gemini-like (geminoid) alkylated amphiphilic peptides containing lysines in combination with glycines or alanines (C15H31C(O)-Lys-(Gly or Ala)nLys-NHC16H33, shorthand notation C16-KXnK-C16 with X = A or G, and n = 0–2). The representatives with 1 or 2 Ala inhibit dengue protease and human furin, two serine proteases involved in dengue virus infection that have peptides with cationic amino acids as their preferred substrates, with IC50 values in the lower µM range. The geminoid C16-KAK-C16 combined inhibition of DENV2 protease (IC50 2.3 µM) with efficacy against replication of wildtype DENV2 in LLC-MK2 cells (EC50 4.1 µM) and an absence of toxicity. We conclude that the lysine-based geminoids have activity against dengue virus infection, which is based on their inhibition of the proteases involved in viral replication and are therefore promising leads to further developing antiviral therapeutics, not limited to dengue. 相似文献
682.
K. Janssens A. L. Bugaev E. G. Kozyr V. Lemmens A. A. Guda O. A. Usoltsev S. Smolders A. V. Soldatov D. E. De Vos 《Chemical science》2022,13(35):10251
This work establishes structure–property relationships in Ru-based catalytic systems for selective hydrodeoxygenation of ketones to alkenes by combining extensive catalytic testing, in situ X-ray absorption spectroscopy (XAS) under high pressures and temperatures and ex situ XAS structural characterization supported by density functional theory (DFT) calculations. Catalytic tests revealed the difference in hydrogenation selectivity for ketones (exemplified by acetone) or alkenes (exemplified by propene) upon changing the reaction conditions, more specifically in the presence of CO during a pretreatment step. XAS data demonstrated the evolution of the local ruthenium structure with different amounts of Cl/Br and CO ligands. In addition, in the absence of CO, the catalyst was reduced to Ru0, and this was associated with a significant decrease of the selectivity for ketone hydrogenation. For the Ru–bromide carbonyl complex, selectivity towards acetone hydrogenation over propene hydrogenation was explained on the basis of different relative energies of the first intermediate states of each reaction. These results give a complete understanding of the evolution of the Ru species, used for the catalytic valorization of biobased polyols to olefins in ionic liquids, identifying the undesired deactivation routes as well as possibilities for reactivation.This work establishes structure–property relationships in Ru-based catalytic systems for the selective hydrodeoxygenation of ketones to alkenes. 相似文献
683.
François Janssens 《Fresenius' Journal of Analytical Chemistry》1865,4(1):48-50
Ohne ZusammenfassungAus dem Holländischen übertragen von der Redaction. 相似文献
684.
Dr. Bethany R. Hood Dr. Yovan de Coene Afonso V. Torre Do Vale Froes Dr. Claire F. Jones Dr. Pierre Beaujean Dr. Vincent Liégeois Dr. Fraser MacMillan Prof. Benoît Champagne Prof. Koen Clays Dr. John Fielden 《Angewandte Chemie (International ed. in English)》2023,62(5):e202215537
Electrochemically switched 2nd order non-linear optical responses have been demonstrated for the first time in polyoxometalates (POMs), with an arylimido-derivative showing a leading combination of high on/off contrast (94 %), high visible transparency, and cyclability. Spectro-electrochemical and TD-DFT studies indicate that the switch-off results from weakened charge transfer (CT) character of the electronic transitions in the reduced state. This represents the first study of an imido-POM reduced state, and demonstrates the potential of POM hybrids as electrochemically activated molecular switches. 相似文献
685.