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41.
Reynolds AM 《Physical review letters》2003,91(8):084503
The Lagrangian stochastic model of Reynolds [Phys. Fluids 15, L1-4 (2003)]] for the accelerations of fluid particles in turbulence is shown to predict precisely the observed Reynolds-number dependency of the distribution of Lagrangian accelerations and the exponents characterizing the observed extended self-similarity scaling of the Lagrangian velocity structure functions. Departures from superstatistics of the log-normal kind are accounted for and their impact upon model predictions is quantified. 相似文献
42.
Several novel glycofuranoses disaccharides related to mycobacterial cell wall polysaccharides were synthesized regio- and stereoselectively using 2,3,5-tri-O-benzoyl-alpha-D-arabinofuranosyl trichloroacetimidate as a glycosyl donor. 相似文献
43.
Brian N. Figgis Philip A. Reynolds Alexandre N. Sobolev 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):731-734
The crystal structures of the α‐alums rubidium chromium bis(sulfate) dodecahydrate, RbCr(SO4)2·12H2O, and caesium chromium bis[tetraoxoselenate(VI)] dodecahydrate, CsCr(SeO4)2·12H2O, have been determined by X‐ray diffraction at 293 and 12 K. The metal atoms lie on sites and the anions lie on threefold rotation axes. The accurate and extensive data sets lead to much more precise determinations than are available from earlier work, particularly at 12 K. The changes in the atomic displacement parameters between 293 and 12 K correspond to the respective predominances of intermolecular and intramolecular vibrational effects. 相似文献
44.
A Metal–Organic Framework with Cooperative Phosphines That Permit Post‐Synthetic Installation of Open Metal Sites 下载免费PDF全文
Samuel G. Dunning Gianne Nandra Adam D. Conn Wenrui Chai R. Eric Sikma Ji Sun Lee Pranaw Kunal Joseph E. Reynolds III Jong‐San Chang Alexander Steiner Graeme Henkelman Simon M. Humphrey 《Angewandte Chemie (International ed. in English)》2018,57(30):9295-9299
PCM‐101 is a phosphine coordination material comprised of tris(p‐carboxylato)triphenylphosphine and secondary pillaring groups coordinated to [M3(OH)]5+ nodes (M=Co, Ni). PCM‐101 has a unique topology in which R3P: sites are arranged directly trans to one another, with a P???P separation distance dictated by the pillars. Post‐synthetic coordination of soft metals to the P: sites proceeds at room temperature to provide X‐ray quality crystals that permit full structural resolution. Addition of AuCl groups forces a large distortion of the parent framework. In contrast, CuBr undergoes insertion directly between the trans‐P sites to form dimers that mimic solution‐phase complexes, but that are geometrically strained due to steric pressure exerted by the MOF scaffold. The metalated materials are active in heterogeneous hydroaddition catalysis under mild conditions, yielding different major products compared to their molecular counterparts. 相似文献
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The title compound was prepared by the condensation of 4,6-diphenyl-2H-pyran-2-one and acetophenone in phosphorus oxychloride. The absorption spectrum of this 2,2-methine dye is compared with those of the corresponding 2,4- and 4,4-methine dyes. 相似文献
47.
Peter E. R. Blanchard Emily Reynolds Brendan J. Kennedy Chris D. Ling Zhaoming Zhang Gordon Thorogood Bruce C. C. Cowie Lars Thomsen 《Journal of synchrotron radiation》2014,21(6):1275-1281
Tc L3‐edge XANES spectra have been collected on powder samples of SrTcO3 (octahedral Tc4+) and NH4TcO4 (tetrahedral Tc7+) immobilized in an epoxy resin. Features in the Tc L3‐edge XANES spectra are compared with the pre‐edge feature of the Tc K‐edge as well as other 4d transition metal L3‐edges. Evidence of crystal field splitting is obvious in the Tc L3‐edge, which is sensitive to the coordination number and oxidation state of the Tc cation. The Tc L3 absorption edge energy difference between SrTcO3 (Tc4+) and NH4TcO4 (Tc7+) shows that the energy shift at the Tc L3‐edge is an effective tool for studying changes in the oxidation states of technetium compounds. The Tc L3‐edge spectra are compared with those obtained from Mo and Ru oxide standards with various oxidation states and coordination environments. Most importantly, fitting the Tc L3‐edge to component peaks can provide direct evidence of crystal field splitting that cannot be obtained from the Tc K‐edge. 相似文献
48.
Frey GL Reynolds KJ Friend RH Cohen H Feldman Y 《Journal of the American Chemical Society》2003,125(19):5998-6007
The development of low-cost, large-area electronic applications requires the deposition of active materials in simple and inexpensive techniques at room temperature, properties usually associated with polymer films. In this study, we demonstrate the integration of solution-processed inorganic films in light-emitting diodes. The layered transition metal dichalcogenide (LTMDC) films are deposited through Li intercalation and exfoliation in aqueous solution and partially oxidized in an oxygen plasma generator. The chemical composition and thickness of the LTMDC and corresponding transition metal oxide (TMO) films are investigated by X-ray photoelectron spectroscopy. The morphology and topography of the films are studied by atomic force microscopy. X-ray powder diffraction is used to determine the orientation of the LTMDC film. Finally, the LTMDC and their corresponding oxides are utilized as hole-injecting and electron-blocking materials in polymer light-emitting diodes with the general structure ITO/LTMDC/TMO/polyfluorene/Ca/Al. Efficient hole injection and electron blocking by the inorganic layers result in outstanding device performance and high efficiency. 相似文献
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