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排序方式: 共有420条查询结果,搜索用时 46 毫秒
41.
M. Sugawara Y. Toh T. Czosnyka M. Oshima T. Hayakawa H. Kusakari Y. Hatsukawa J. Katakura N. Shinohara M. Matsuda T. Morikawa A. Seki F. Sakata 《The European Physical Journal A - Hadrons and Nuclei》2003,16(3):409-414
Electromagnetic properties of the low-lying states in a 70Ge nucleus were studied through the multiple Coulomb excitation of a 70Ge beam with a natPb target. Relative γ-ray intensities were measured as a function of emission angle relative to the scattered projectile.
Sixteen E2 matrix elements, including diagonal ones, for 6 low-lying states have been determined using the least-squares search code
GOSIA. The expectation values 〈Q
2〉 of 01
+ and 02
+ states in 70Ge are compared with those in 72, 74, 76Ge. Simple mixing calculations indicate that the 02
+ states in 70Ge and 72Se can be treated as deformed intruder states. It is shown that the deformed intruder becomes the ground state in 74Kr. These interpretations of the 02
+ states in this region are compared with the potential-energy surface calculations by the Nilsson-Strutinsky model, which
allow to interpret the experimental results in a qualitative way from the theoretical point of view.
Received: 2 September 2002 / Accepted: 5 November 2002 / Published online: 25 February 2003
RID="a"
ID="a"e-mail: sugawara@pf.it-chiba.ac.jp
Communicated by D. Schwalm 相似文献
42.
A laser-induced forward transfer technique has been applied for the maskless patterning of amorphous V2O5 thin films. A sheet beam of a frequency doubled (SHG) Q-switched Nd:YAG laser was irradiated on a transparent glass substrate (donor), the rear surface of which was pre-coated with a vacuum-deposited V2O5 180 nm thick film was either in direct contact with a second glass substrate (receiver) or a 0.14 mm air-gap was maintained between the donor film and the receiving substrate. Clear, regular stripe pattern of the laser-induced transferred film was obtained on the receiver. The pattern was characterized using X-ray diffraction (XRD), optical absorption spectroscopy, scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), atomic force microscopy (AFM), etc. 相似文献
43.
44.
We have made theoretical studies on the limitation of the open-circuit voltageV
oc of a hydrogenated amorphous silicon (a-Si:H) p-i-n type solar cell. The effects of the tail states in the a-Si:H i layer and of the interface recombination are discussed in detail. The opencircuit voltage increases when the distribution of the tail states is sharp and/or the capture cross sections of these states are small. This is because the recombination rate of photogenerated carriers and/or the density of space charge due to trapped carriers in these states become low in these conditions. These effects of the tail states on the value ofV
oc become pronounced when the built-in potential of the p-i-n junction is high. The decrease in the effective recombination velocity of carriers at the p/i and n/i interfaces results in an increase ofV
oc. This increase becomes remarkable when the effects of the tail states on the value ofV
oc are small. Both the sharp distribution of tail states and the small value of the interface recombination velocity are necessary to increase considerably the value ofV
oc. We show the conditions of the material parameters necessary to obtain an open-circuit voltage of 1.0 V. 相似文献
45.
46.
Kentaro Okuma Jun-ichi Sakata Yuji Tachibana Takumi Honda Hiroshi Ohta 《Tetrahedron letters》1987,28(52):6649-6652
Wittig reagents were successfully changed to symmetrical olefins when treated with elemental selenium. The reaction proceeds through a selenocarbonyl intermediate, which existence was confirmed by Diels-Alder reaction. 相似文献
47.
Harada T Ikeda S Hashimoto F Sakata T Ikeue K Torimoto T Matsumura M 《Langmuir : the ACS journal of surfaces and colloids》2010,26(22):17720-17725
A core-shell composite consisting of a palladium (Pd) nanoparticle and a hollow carbon shell (Pd@hmC) was employed as a catalyst for aerobic oxidation of various alcohols. The core-shell structure was synthesized by consecutive coatings of Pd nanoparticles with siliceous and carbon layers followed by removal of the intermediate siliceous layer. Structural characterizations using TEM and N(2) adsorption-desorption measurements revealed that Pd@hmC thus-obtained was composed of a Pd nanoparticle core of 3-6 nm in diameter and a hollow carbon shell with well-developed mesopore (ca. 2.5 nm in diameter) and micropore (ca. 0.4-0.8 nm in diameter) systems. When compared to some Pd-supported carbons, Pd@hmC showed a high level of catalytic activity for oxidation of benzyl alcohol into benzaldehyde using atmospheric pressure of O(2) as an oxidant. The Pd@hmC composite also exhibited a high level of catalytic activity for aerobic oxidations of other primary benzylic and allylic alcohols into corresponding aldehydes. The presence of a well-developed pore system in the lateral carbon shell enabled efficient diffusion of both substrates and products to reach the central Pd nanoparticles, leading to such high catalytic activities. This core-shell structure also provided high thermal stability of Pd nanoparticles toward coalescence and/or aggregation due to the physical isolation of each Pd nanoparticle from neighboring particles by the carbon shell: this specific property of Pd@hmC resulted in possible regeneration of catalytic activity for these aerobic oxidations by a high-temperature heat treatment of the sample recovered after catalytic reactions. 相似文献
48.
Katsuhide Murata Mihai Brebu Yusaku Sakata 《Journal of Analytical and Applied Pyrolysis》2010,89(1):30-38
Catalytic degradation of polyolefins was performed in a continuous flow reactor that allows the study of the degradation processes at steady state, characterized by constant values of reaction parameters and properties of the products. The continuous flow reactor was operated at atmospheric pressure and at feed rate of 0–1.5 kg h?1 polyolefins over two silica–alumina catalysts having different SiO2/Al2O3 mole ratio. Polyethylene (PE), polypropylene (PP) and polystyrene (PS) were degraded at 420, 380 and 360 °C respectively. The cracking effect of silica–alumina was proved by the increased amount of gaseous products and by the decreased molecular weight of liquid products. The differences in surface area and in concentration and acidic strength of active centers of the two catalysts affected the distribution of degradation products. Molar rate of degradation was increased in the presence of catalysts, however the mass rate of degradation was decreased leading to higher values of the calculated activation energies. These interesting results might open new perspectives in understanding the macroscopic mechanism for catalytic degradation of polyolefins. 相似文献
49.
Yoshiteru Sakata Hiroshi Imahori Ken-Ichi Sugiura 《Journal of inclusion phenomena and macrocyclic chemistry》2001,41(1-4):31-36
Guidelines for the design of molecules with a long lifetime of the charge-separated state and for the formation of a self-assembled monolayer were studied by preparing various model compounds linking donor and acceptor with chemical bonds. Based on the obtained results we designed and prepared the SAMs of C60-(porphyrin)-(ferrocene)-(CH2)11SH on a gold surface and observed a photocurrent with high efficiency (25% quantum yield). In addition, a well-defined, rigid-sheet-structured oligoporphyrin with 21 porphyrin chromophores was prepared as a model for antenna chlorophylls. 相似文献
50.