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361.
Electronic interaction of m-aminoacetophenone (MAAP) with t-amyl alcohol in the excited state has been investigated by steady-state and nanosecond spectroscopies. It was shown that the MAAP molecules forms a complex with two t-amyl alcohol molecules in the ground state, and that the complex further associates with the alcohol molecules in the excited state. 相似文献
362.
Yoshifumi Ikoma Takayoshi Masaki Shinji Kawai Teruaki Motooka 《Applied Surface Science》2007,253(21):8657-8660
We report on Si nanodot formation by chemical vapor deposition (CVD) of ultrathin films and following oxidation. The film growth was carried out by hot-filament assisted CVD of CH3SiH3 and Dy(DPM)3 gas jets at the substrate temperature of 600 °C. The transmission electron microscopy observation and X-ray photoelectron spectroscopy analysis indicated that ∼35 nm Dy-doped amorphous silicon oxycarbide (SiCxOy) films were grown on Si(1 0 0). The Dy concentration was 10-20% throughout the film. By further oxidation at 860 °C, the smooth amorphous film was changed to a rough structure composed of crystalline Si nanodots surrounded by heavily Dy-doped SiO2. 相似文献
363.
Nishino MN Fujimoto M Phan TD Mukai T Saito Y Kuznetsova MM Rastätter L 《Physical review letters》2008,101(6):065003
Earth's magnetosphere is an obstacle to the supersonic solar wind and the bow shock is formed in the front side of it. In ordinary hydrodynamics, the flow decelerated at the shock is diverted around the obstacle symmetrically about the Earth-Sun line, which is indeed observed in the magnetosheath most of the time. Here we show a case under a very low-density solar wind in which duskward flow was observed in the dawnside magnetosheath. A Rankine-Hugoniot test shows that the magnetic effect is crucial for this "wrong flow" to appear. A full three-dimensional magnetohydrodynamics (MHD) simulation of the situation confirming this interpretation and earlier simulations is also performed. It is illustrated that in addition to the "wrong flow" feature, various peculiar characteristics appear in the global picture of the MHD flow interaction with the obstacle. 相似文献
364.
2-Aryl-1-phenyl-5-styrylphospholes were prepared in good yields in a one-pot procedure from the corresponding 1,9-diarylnona-8-ene-1,6-diynes and dichloro(phenyl)phosphine via intermediary titanacyclopentadienes. According to the UV-vis absorption and fluorescence spectra of this class of compounds, the optical properties of the phosphole-vinylene-bridged pi-conjugated system have been revealed to depend strongly on the electronic character of the terminal functionalities. In particular, the polarizability at the excited-state has been found to be considerably greater than that in the ground state. High molecular hyperpolarizabilities obtained for the push-pull type of 2-aryl-5-styrylphospholes in the hyper-Rayleigh scattering measurements demonstrate the potential utility of the stilbene-type phosphole derivatives as a new class of second-order NLO chromophores. 相似文献
365.
Magnetic field effect on chemical wave propagation from the Belousov-Zhabotinsky reaction 总被引:1,自引:0,他引:1
Nishikiori R Morimoto S Fujiwara Y Katsuki A Morgunov R Tanimoto Y 《The journal of physical chemistry. A》2011,115(18):4592-4597
Effects of magnetic field (maximum field, 4 and 93 T(2) m(-1)) on the propagation speed of a chemical wavefront from the Belousov-Zhabotinsky reaction were studied in a thin glass tube. The downward and upward speed and the horizontal one are, respectively affected significantly by vertical and horizontal magnetic fields. Observations of the wavefront shape in magnetic fields showed that the magnetic force-induced convection causes the observed effects. 相似文献
366.
Changsheng Ding Hongfei Lin Kazuhisa Sato Yoshifumi Tsutai Hiromichi Ohtaki Mabito Iguchi 《Journal of Dispersion Science and Technology》2013,34(2):241-245
Spray coating method is a cost-effective technique suitable for the preparation of uniform and large-area thin films. This article presents findings on the preparation of dense electrolyte thin films by spray coating method. Dense, crack-free Gd-doped CeO2 (GDC) thin films with a thickness of approximately 2 µm were successfully prepared on porous NiO-GDC substrates. The influence of the dispersion of GDC nanopowders in susupension on the microstructure of the thin films was investigated. Results show that agglomeration of GDC nanopowders in suspension resulted in a porous microstructure and a densely packed microstructure was obtained for the film prepared from a well-dispersed suspension. 相似文献
367.
HC-SCR (selective reduction of nitrogen oxide by hydrocarbon) and our view on its reaction mechanism are briefly described,
and then our attempts in the last few years to design catalysts based on the concept of bifunctional catalysis for HC-SCR
are reviewed. The example chosen is the NO-C3H6-O2-H2O reaction catalyzed by mechanical mixtures of transition metal oxides (e.g., Mn2O3) and metal-loaded ZSM-5 zeolites. The synergistic effect of two components was explained based on a reaction mechanism comprising
NO oxidation, oxidative decomposition of the products of NO2-C3H6 reactions and polymerization of (or carbon deposition from) C3H6. 相似文献
368.
Yoshifumi Nagumo Kazuya Tanaka Kaushal Tewari Khwankaew Thiraporn Toru Tsuchida Toshimitsu Honma Norikuni Ohtake Kuni Sueyoshi Yoshihiko Takahashi Takuji Ohyama 《Journal of chromatography. A》2009,1216(29):5614-5618
A rapid and simple method for determination of cyanamide in fertilizer, soil and plants has been developed. In this method, cyanamide is extracted with 2% acetic acid and the extract separated by centrifugation. It is then purified by passing through a membrane filter. The extract was derivatized with 6-aminoquinolyl-N-hydroxysuccinimidyl-carbamate and the derivatized compound separated by ultra-high-pressure liquid chromatography. It is then detected with a UV detector at 260 nm by the same method as is used for amino acid analysis. The proposed method is fast, simple and cheap and also has good selectivity and sensitivity for the determination of cyanamide in a wide range of biotic and abiotic materials. 相似文献
369.
Takamizawa A Itoh Y Osawa R Iwasaki N Nishimura Y Akashi S Hiraoka K 《Journal of mass spectrometry : JMS》2004,39(9):1053-1058
The laser spray developed in our laboratory was applied to the analysis of bovine serum albumin (BSA), double-stranded DNA (dsDNA) and a protein-DNA complex. The tip of a stainless-steel capillary was irradiated with a 10.6 micro m infrared laser by increasing the laser power from 0 W (electrospray) to 1.4 W. The laser beam was focused to about 0.3 mm at the tip of the stainless-steel capillary. When BSA aqueous solution was irradiated by the laser, highly charged monomer ions were newly observed in addition to the multiply charged ions of non-denatured monomer, dimer and trimer moieties. This indicates that BSA suffers from denaturation on irradiation with an infrared laser in solution. A 1.4 W laser power is not sufficient to cause the complete denaturation of BSA under the present experimental conditions. Whereas dsDNA was found to dissociate almost completely to single-stranded DNA constituents on laser irradiation with a power of 1.2 W, no fragmentation of DNA molecules was observed. For a protein-DNA complex, i.e. a complex of c-Myb DNA binding domain and dsDNA, dissociation of the complex to the component moieties was observed. These findings indicate that the laser spray can selectively dissociate non-covalent complexes into subunits without causing dissociation of the covalent bonds of the subunits. The laser spray will be a versatile method for the investigation of the structures and stabilities of biomolecules including non-covalent complexes. 相似文献
370.
Automatized Parameterization of the Density‐functional Tight‐binding Method. II. Two‐center Integrals 下载免费PDF全文
Henryk A. Witek Chien‐Pin Chou Grzegorz Mazur Yoshifumi Nishimura Stephan Irle Bálint Aradi Thomas Frauenheim Keiji Morokuma 《中国化学会会志》2016,63(1):57-68
We present an efficient numerical integration scheme (TWOCENT) to be used in the context of automatized parameterization of the density‐functional tight‐binding (DFTB) method. The accuracy of the integration process is assessed and its range of applicability is discussed. The functionality of the developed code is tested by reproducing the electronic portion of the existing mio parameter sets and by reproducing a series of reference DFT band structures of elemental solids. 相似文献