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31.
Yasutaka Kuwahara Takashi Mihogi Koji Hamahara Kazuki Kusu Hisayoshi Kobayashi Hiromi Yamashita 《Chemical science》2021,12(29):9902
Production of methanol from anthropogenic carbon dioxide (CO2) is a promising chemical process that can alleviate both the environmental burden and the dependence on fossil fuels. In catalytic CO2 hydrogenation to methanol, reduction of CO2 to intermediate species is generally considered to be a crucial step. It is of great significance to design and develop advanced heterogeneous catalysts and to engineer the surface structures to promote CO2-to-methanol conversion. We herein report an oxygen-defective molybdenum sub-oxide coupled with Pt nanoparticles (Pt/HxMoO3−y) which affords high methanol yield with a methanol formation rate of 1.53 mmol g-cat−1 h−1 in liquid-phase CO2 hydrogenation under relatively mild reaction conditions (total 4.0 MPa, 200 °C), outperforming other oxide-supported Pt catalysts in terms of both the yield and selectivity for methanol. Experiments and comprehensive analyses including in situ X-ray absorption fine structure (XAFS), in situ diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy and density functional theory (DFT) calculations reveal that both abundant surface oxygen vacancies (VO) and the redox ability of Mo species in quasi-stable HxMoO3−y confer the catalyst with enhanced adsorption and activation capability to subsequently transform CO2 to methanol. Moreover, the Pt NPs act as H2 dissociation sites to regenerate oxygen vacancies and as hydrogenation sites for the CO intermediate to finally afford methanol. Based on the experimental and computational studies, an oxygen-vacancy-mediated “reverse Mars–van Krevelen (M–vK)” mechanism is proposed. This study affords a new strategy for the design and development of an efficient heterogeneous catalyst for CO2 conversion.Oxygen-defective molybdenum sub-oxide coupled with Pt nanoparticles affords high methanol yield in liquid-phase CO2 hydrogenation via reverse Mars–van Krevelen mechanism. 相似文献
32.
Hiroshi Maruyama Masao Shiozaki Sadao Oida Tetsuo Hiraoka 《Tetrahedron letters》1985,26(37):4521-4522
Base treatment of N-propargyl epoxyamide 5 afforded the acetylenic 3-(hydroxyethyl)-2-azetidinone 9a, which was subsequently transformed to phenyl thiolester 2, a versatile intermediate for the carbapenem synthesis. 相似文献
33.
Naoko Morisaki Jun Furukawa Hisayoshi Kobayashi Shigeo Iwasaki Shigeo Nozoe Shigenobu Okuda 《Tetrahedron letters》1985,26(39):4755-4758
Deuterium labeled -6-protoilludene () was synthesized and fed to the illudin-producing fungus (ATCC 11719). The hydrocarbon () was incorporated into illudin-M () and -S (). 相似文献
34.
Noguchi H Yoda E Ishizawa N Kondo JN Wada A Kobayashi H Domen K 《The journal of physical chemistry. B》2005,109(36):17217-17223
The reaction dynamics of trans-2-butene adsorbed to acidic hydroxyl groups on the surface of ferrierite zeolite is examined by time-resolved spectroscopy using a tunable infrared picosecond pulse laser system. The transient absorption spectra measured by a two-color pump-probe technique at 188-243 K reveal bleaching and hot bands of the OD stretching mode 2 ps after excitation. This vibrationally excited state relaxes within 20 ps at 188 K, while the bleaching band includes a long-lifetime component that lasts for more than 100 ps at 243 K. Thus, the OD (isotope-exchanged hydroxy groups) stretching band does not entirely recover in this period and is mirrored by an analogous weakening of the CH bending band of the adsorbed trans-2-butene. Simultaneously, three new bands in CH stretching region were observed at 3045, 3095, and 3130 cm(-1). This result suggests the presence of a short-lived intermediate formed by reaction between the acidic hydroxyl groups and adsorbed trans-2-butene. 相似文献
35.
Hisayoshi Kobayashi Masaru Yamaguchi Satohiro Yoshida 《Theoretical chemistry accounts》1982,61(5):473-484
A method is presented to represent the chemisorptive interactions concisely. The canonical molecular orbitals of a chemisorption system are transformed into new orbitals where the charge transfer interactions between the surface and the adsorbate are maximized or minimized. The chemisorptive bonds are well described by a small number of the transformed orbitals. The analysis of chemisorptive interactions is carried out for the Pt(111) + CO, W(110) + CO and Pt(112) + CO systems. The weakening of the C-O bond in the W(110) face and in the trench region of the Pt(112) face is larger than that in the Pt(111) face in conformity with the experimental data. The interactions are, to a good approximation, represented by five or six orbitals and are explained in terms of the and donation of CO to the surface and the back donation to CO. 相似文献
36.
Sato J Saito N Yamada Y Maeda K Takata T Kondo JN Hara M Kobayashi H Domen K Inoue Y 《Journal of the American Chemical Society》2005,127(12):4150-4151
Germanium nitride beta-Ge3N4 dispersed with RuO2 nanoparticles is presented as the first example of a non-oxide photocatalyst for the stoichiometric decomposition of H2O into H2 and O2. All of the successful photocatalysts developed for overall water splitting over the past 30 years have been based on oxides of metals. The discovery of a non-oxide photocatalyst, such as nitrides and oxynitrides, achieving the same function is therefore expected to stimulate research on non-oxide photocatalysts. New opportunities for progress in the development of visible light-driven photocatalysis can thus be expected, as the higher valence band positions of metal nitrides compared to the corresponding metal oxides provide narrower band gaps, which are suitable for visible light activity. 相似文献
37.
Takiguchi Yu Seo Min-Woong Kagawa Keiichiro Takamoto Hisayoshi Inoue Takashi Kawahito Shoji Terakawa Susumu 《Optical Review》2016,23(2):364-368
Optical Review - We propose a novel full-electronically controlled laser confocal microscope in which a liquid-crystal-on-silicon spatial light modulator and a custom CMOS imaging sensor are... 相似文献
38.
Lipid A analogues containing a glucose moiety on their non-reducing end were synthesized, and their LPS-antagonistic activities were measured. The inhibitory activities (IC50) on LPS-induced TNFα production of these six compounds, 26, 33, 44β, 52β, 59, and 61, toward human whole blood cells were 0.49, 0.65, 0.51, 0.98, 0.46, and 1.11 nM, respectively. Inhibitory doses (ID50) of compounds 26, 33, 44β, 59, and 61 on TNFα production induced by coinjection of galactosamine and LPS in C3H/HeN mice were measured. The ID50 values of these compounds were 0.45, 0.96, <0.2, 1.08, and <0.2 mg/kg, respectively. Moreover, C3H/HeN mice preinjected with compounds 26, 33, and 44β were protected from lethality induced by coinjection of galactosamine and LPS. Out of eight mice preinjected with 1 mg/kg of compounds 26, 33, and 44β, five, eight and six mice were protected, respectively. 相似文献
39.
S. Sugai Y. Takayanagi N. Hayamizu T. Muroi J. Nohara R. Shiozaki K. Okazaki K. Takenaka 《Physica C: Superconductivity and its Applications》2010
Electronic Raman scattering has no sum rule in no and weak correlation, but the existence of sum rule has been proposed in strong correlation. The present Raman scattering disclosed that the first moment of the Raman susceptibility is proportional to the generalized moment of the optical conductivity in the metallic phase. The present experiment disclosed that a large amount of electronic states are incoherent states. The incoherent states are the relevant states for the superconductivity, because the gap opens in the incoherent states as well as the coherent states. 相似文献
40.
An internally contracted multireference configuration interaction is developed which employs wave functions that explicitly depend on the electron-electron distance (MRCI-F12). This MRCI-F12 method has the same applicability as the MRCI method, while having much improved basis-set convergence with little extra computational cost. The F12b approximation is used to arrive at a computationally efficient implementation. The MRCI-F12 method is applied to the singlet-triplet separation of methylene, the dissociation energy of ozone, properties of diatomic molecules, and the reaction barrier and exothermicity of the F + H(2) reaction. These examples demonstrate that already with basis sets of moderate size the method provides near complete basis set MRCI accuracy, and hence quantitative agreement with the experimental data. As a side product, we have also implemented the explicitly correlated multireference averaged coupled pair functional method (MRACPF-F12). 相似文献