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Doubina N Jenkins JL Paniagua SA Mazzio KA MacDonald GA Jen AK Armstrong NR Marder SR Luscombe CK 《Langmuir : the ACS journal of surfaces and colloids》2012,28(3):1900-1908
Poly(3-methylthiophene) (P3MT) was synthesized directly from indium tin oxide (ITO) electrodes modified with a phosphonic acid initiator, using Kumada catalyst transfer polymerization (KCTP). This work represents the first time that polymer thickness has been controlled in a surface initiated KCTP reaction, highlighting the utility of KCTP in achieving controlled polymerizations. Polymer film thicknesses were regulated by the variation of the solution monomer concentration and ranged from 30 to 265 nm. Electrochemical oxidative doping of these films was used to manipulate their near surface composition and effective work function. Doped states of the P3MT film are maintained even after the sample is removed from solution and potential control confirming the robustness of the films. Such materials with controllable thicknesses and electronic properties have the potential to be useful as interlayer materials for organic electronic applications. 相似文献
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Stephen Barlow Michael W. Day Seth R. Marder 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(3):303-304
The 1‐(2,3,4,5,1′,2′,3′,4′‐octamethylferrocen‐1‐yl)‐3‐(ruthenocenyl)allylium cation readily undergoes one‐electron oxidation to a dication in which an octamethylferrocenium moiety is bridged by a vinylene group to a [(η6‐fulvene)(η5‐cyclopentadienyl)ruthenium]+ moiety. In the title compound, 1‐(2,3,4,5,1′,2′,3′,4′‐octamethylferrocen‐1‐yl)‐3‐(ruthenocenylidene)prop‐1‐enium(2+) bis(tetrafluoroborate), [FeRu(C5H5)(C9H13)(C17H19)](BF4)2, the C—C bond lengths in the bridge (average for two independent molecules) are, starting from the ipso octamethylferrocenium carbon and ending at the exo carbon of the coordinated fulvene, 1.455 (6), 1.344 (3) and 1.449 (8) Å, indicating a localized electronic structure. 相似文献
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Jonathan C. Collings Andrei S. Batsanov Judith A. K. Howard Todd B. Marder 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):870-872
The structure of the title complex, C10F8·C14H10, comprises mixed stacks of alternating diphenylacetylene and octafluoronaphthalene molecules, both lying at inversion centres and parallel to within 8.6 (1)°, in contrast with the herring‐bone packing observed in crystals of either pure component. 相似文献
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Lei Ji Stefan Riese Alexander Schmiedel Marco Holzapfel Maximillian Fest Jrn Nitsch Basile F. E. Curchod Alexandra Friedrich Lin Wu Hamad H. Al Mamari Sebastian Hammer Jens Pflaum Mark A. Fox David J. Tozer Maik Finze Christoph Lambert Todd B. Marder 《Chemical science》2022,13(18):5205
Reversible conversion between excited-states plays an important role in many photophysical phenomena. Using 1-(pyren-2′-yl)-o-carborane as a model, we studied the photoinduced reversible charge-transfer (CT) process and the thermodynamic equilibrium between the locally-excited (LE) state and CT state, by combining steady state, time-resolved, and temperature-dependent fluorescence spectroscopy, fs- and ns-transient absorption, and DFT and LR-TDDFT calculations. Our results show that the energy gaps and energy barriers between the LE, CT, and a non-emissive ‘mixed’ state of 1-(pyren-2′-yl)-o-carborane are very small, and all three excited states are accessible at room temperature. The internal-conversion and reverse internal-conversion between LE and CT states are significantly faster than the radiative decay, and the two states have the same lifetimes and are in thermodynamic equilibrium.Reversible conversion between excited-states is key to many photophysical phenomena. We studied the equilibrium between LE and CT states by time-resolved and temperature-dependent fluorescence, fs- and ns-transient absorption, and LR-TDDFT calculations. 相似文献
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The vibronic profiles of one-photon absorption spectra of dioxaborine heterocycles in gas phase and solution have been calculated at the Hartree-Fock and density-functional-theory levels. The polarizable continuum model has been applied to simulate the solvent effect, while the linear coupling model is used to compute the Franck-Condon and Herzberg-Teller contributions. It is found that a good agreement between theory and experiment can be achieved when the solvent effect and electron correlation are taken into account simultaneously. For the first excited charge-transfer state, the maximum of its Herzberg-Teller profile is blueshifted from that of the Franck-Condon profile. The shifted energy is found to be around 0.2 eV, which agrees well with the measured energy difference between two- and one-photon absorptions of the first excited state. 相似文献