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51.
The decay of one monolayer gold atoms at the nickel surface by bombardment with 5 keV Ar+ ions at room temperature has been studied by means of the RBS technique. It is found that the gold concentration decreases bi-exponentially with increasing ion fluence. It is shown that the fast decay component gives the removal cross-section which is the summation of the desorption and the recoil-implantation cross-sections. The recoil-implantation cross-section is evaluated from the difference between the removal cross-section and the desorption cross-section obtained at a previous high-temperature experiment. 相似文献
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54.
This article describes a pilot plant test, which was carried out to examine the effect of start-up operation conditions on catalytic performance in the commercial hydrotreating equipment. From the simulated several pilot tests, it was found that the operation conditions of this commercial equipment were very severe and the hydrogen supply to the catalyst active site was critical. When the heavy residue containing large amount of asphaltene was supplied at the start of run (SOR) in the commercial equipment, the permanent adsorption of carbonaceous deposit on the active site should cause leading the catalyst deactivation. 相似文献
55.
A truncation scheme of the Bogoliubov-Born-Green-Kirkwood-Yvon hierarchy for reduced density matrices, where a three-body density matrix is approximated by the antisymmetrized products of two-body density matrices, is proposed. This truncation scheme is tested for three model Hamiltonians. It is shown that the obtained results are in good agreement with the exact solutions. 相似文献
56.
Zhi Zhi Hu Shizuka Takami Masaru Kimura Yoshimitsu Tachi Yoshinori Naruta 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(10):e465-e466
The structure of lophine peroxide was confirmed to be 2,4,5‐triphenyl‐4H‐imidazol‐4‐yl hydroperoxide and not the 2,5‐endoperoxide. The asymmetric unit is composed of an O—H?N hydrogen‐bonded dimer of lophine peroxide with an R/R or S/S configuration and a CH2Cl2 solvent molecule, i.e. 2C21H16N2O2·CH2Cl2. 相似文献
57.
M. Yoshida K. Ishii K. Ikeuchi I. Jarrige Y. Murakami J. Mizuki K. Tsutsui T. Tohyama S. Maekawa K. Kudo Y. Koike Y. Endoh 《Physica C: Superconductivity and its Applications》2010
We report a resonant inelastic X-ray scattering (RIXS) study of charge excitations in the two-leg ladder Sr14Cu24O41. RIXS spectra at 1–5 eV are found to be dependent on temperature. An intraband excitation of the ladder, which appears as a continuum intensity below the Mott gap, decreases in intensity with temperature. Because the intraband excitation is related to the dynamics of doped holes in the ladder, its decrease of the intraband excitation is attributed to the reduction of the mobile holes in the ladder at low temperature. 相似文献
58.
Ye T Takami T Wang R Jiang J Weiss PS 《Journal of the American Chemical Society》2006,128(34):10984-10985
Lanthanide double-decker (DD) complexes represent an interesting system to engineer intermolecular interactions at different distances from the surface. Such atomic-level understanding and control are crucial for the development of molecular devices with three-dimensional complexity. We herein demonstrate an example of how the surface arrangements of DD molecules are influenced by varying intermolecular interactions. By varying the size of a ligand, we observed significant expansion of the lattice even though the top ligands of DD molecules remain too small to interact directly with each other. We also demonstrate that DD molecules in different local environments adopt significantly different structures. Such structures suggest that subtle interactions exist between the top ligand of one molecule and the bottom ligands of its neighbors. 相似文献
59.
Sugiyama J Nozaki H Ikedo Y Mukai K Andreica D Amato A Brewer JH Ansaldo EJ Morris GD Takami T Ikuta H 《Physical review letters》2006,96(19):197206
The quasi-one-dimensional (Q1D) cobalt oxides A(N + 2)Co(n + 1)O(3n + 3) (A = Ca, Sr, and Ba, n = 1 - infinity) were investigated by muon-spin spectroscopy under applied pressures of up to 1.1 GPa. The relationship between the onset Néel temperature T(on)(N) and the interchain distance (d(ic)), which increases monotonically with n, is well fitted by the formula T(N)/T(N,0) = (1 - d(ic)/d(ic,o)(beta), here for T(on)(N) approximately 100 K for Ca(3)Co(2)O(6) (n = 1) and approximately 15 for BaCoCoO(3) (n = infinity at ambient P. The T(on)(N) - d(ic) curve also predicts a large dependence of Y(N) for the compounds with n > or = 5, i.e., in the vicinity of , while the compounds show only a very small effect. Indeed, our high-pressure mu(+) results show that of BaCoO(3) is enhanced by with a slope of 2.2 K(Gpa), whereas no detectable changes by P for both Ca(3)Co(2)O(6) and Sr(4)Co(3)O(9) (n = 2). This clearly confirms the role of the 2D-antiferromagnetic interaction on T(on)(N) in the Q1D cobalt oxides. 相似文献
60.
E. Simoen C. Claeys H. Ohyama Y. Takami H. Sunaga 《Journal of Radioanalytical and Nuclear Chemistry》1999,239(1):207-211
The impact of several factors, related to the doping density, the substrate type and the thermal pre-treatment on the proton
radiation damage coefficients of Si diodes is discussed and verified experimentally. The diode parameters investigated are
the leakage current density, the recombination lifetime and the low-frequency noise current spectral density. Proton irradiations
have been performed in the energy range 10 MeV to 100 MeV and in the fluence range of 5·109 to 4·1011 cm−2, typical for space applications. The obtained coefficients are compared with theoretical NIEL predictions. 相似文献