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81.
The traditional standard stochastic system models, such as the autoregressive (AR), moving average (MA) and autoregressive moving average (ARMA) models, usually assume the Gaussian property for the fluctuation distribution, and the well-known least squares method is applied on the basis of only the linear correlation data. In the actual sound environment system, the stochastic process exhibits various non-Gaussian distributions, and there exist potentially various nonlinear correlations in addition to the linear correlation between input and output time series. Consequently, the system input and output relationship in the actual phenomenon cannot be represented by a simple model. In this study, a prediction method of output response probability for sound environment systems is derived by introducing a correction method based on the stochastic regression and fuzzy inference for simplified standard system models. The proposed method is applied to the actual data in a sound environment system, and the practical usefulness is verified. 相似文献
82.
Makoto Yanaga Kazutoyo Endo Hiromichi Nakahara Shigeru Ikuta Taichi Miura Masashi Takahashi Masuo Takeda 《Hyperfine Interactions》1989,52(2):147-151
The121Sb Mössbauer spectra of rapidly frozen solutions of antimony compounds were observed. The isomer shifts were compared with the electron density at the antimony nucleus calculated with the ab initio molecular orbital method. A value ΔR/R=?(11±2)×10?4 was derived for the 37.15 keV M1 transition of121Sb. 相似文献
83.
Hamasaki A. Shioji N. Ikuta Y. Hukuda Y. Makita T. Hlrayama K. Matuzaki H. Tukamoto T. Sasaki S. 《Applied biochemistry and biotechnology》1994,45(1):799-809
Applied Biochemistry and Biotechnology - CO2 fixation by microalgal cultures, a potential method for CO2 emissions mitigation, was studied in small (approx 2 m2) ponds using actual flue gas from... 相似文献
84.
Y Matsuda H Hoshika Y Inouye S Ikuta K Matsuura S Nakamura 《Chemical & pharmaceutical bulletin》1987,35(2):711-717
85.
Maeda Isamu Chowdhury Wasimul Q. Idehara Kenji Yagi Kiyohito Mizoguchi Tadashi Akano Toru Mlyasaka Hltoshi Furutani Toshio Ikuta Yoshiaki Shioji Norio Miura Yoshiharu 《Applied biochemistry and biotechnology》1998,(1):301-310
In photosynthetic bacteria, after transition to light-anaerobic and nitrogen-deficient conditions, hydrogen evolution starts
with expression of nitrogenase activity. Until the expression of enough activity,Rhodovulum sulfidophilum consumed substrates and converted them to poly(3-hydrox-ybutyrate) (PHB), resulting in a decrease in the proportion of substrate
converted into hydrogen gas. To prevent conversion to PHB during the period when nitrogenase activity is derepressed, the
authors employed a cultivation method consisting of three stages: cell growth, nitrogenase derepression, and hydrogen production.
Cells cultivated by this method exhibited no lag time before the commencement of hydrogen evolution and gave an improved yield
of hydrogen from the algal fermentative products. 相似文献
86.
Yoshikawa K Ikuta M Arihara S Matsumura E Katayama S 《Chemical & pharmaceutical bulletin》2001,49(8):1030-1032
Two new steroid derivatives, (22E,24R)-3alpha-ureido-ergosta-4,6,8(14),22-tetraene (1) and (22E,24R)-5alpha,8alpha-epidioxyergosta-6,9,22-triene-3beta-ol 3-O-beta-D-glucopyranoside (2) were isolated from the fruit bodies of Chlorophyllum molybdites (Agaricaceae). The structures were established by spectroscopic and chemical methods. These compounds exhibited cytotoxicity against Kato III cells. 相似文献
87.
A new method for standardization of electropherograms obtained by capillary zone electrophoresis was proposed, where the migration time axis was replaced by the effective mobility axis. The mobility increase due to temperature increase by Joule heating and the relaxation effect of the potential gradient were eliminated successfully by introducing a temperature coefficient for mobility expression and a delay time, respectively. The precision of the mobility evaluated by the proposed conversion methods was evaluated for a model sample. By using the conversion method, almost the same electropherograms could be obtained even from the electropherograms originally obtained by using different hardware conditions. 相似文献
88.
The geometric structures and isomeric stabilities of various stationary points in CH2Si2 neutral, cation and anion are investigated at the coupled-cluster singles, doubles (triples) (CCSD(T)) level of theory. For the geometrical survey, the basis sets used are of the cc-pVTZ for the neutral and cation. The final energies are calculated by the use of the CCSD(T) level of theory with the aug-cc-pVTZ basis set at their optimized geometries. To the competitive two-anion isomers, the aug-cc-pVTZ basis sets are applied. The global minimum (N-1) of the CH2Si2 neutral has a quite different framework from those of the C3H2 (cyclopropenylidene) and Si3H2 (trisilacyclopropenylidene) neutrals. No competitive low-lying isomers are found in the CH2Si2 neutral. The attractive conformer (C-1) is predicted for the most stable cation, where its framework is quite different from that of the neutral N-1. Both H atoms are connected to the same C atom, but each C–H bond length is different from each other. Two competitive anion isomers with positive (real) electron affinities are predicted. The framework of the most stable anion A-1 is quite similar to that of the cation C-1, whereas both H atoms are equally connected to the same C atom. The framework of the anion isomer A-2 is the same as that in the neutral N-1. The vertical and adiabatic ionization potentials from the most stable neutral N-1 are 9.02 and 8.71 eV, respectively. The adiabatic electron affinity of the lowest lying isomer N-1 is only 0.43 eV and the vertical electron detachment energy form the global minimum anion (A-1) is 2.02 eV. The multi-centered Si–H–Si bonds are found in the neutral, cation, and anion. 相似文献
89.
Standardization of capillary zone electropherograms obtained by using field enhanced sample stacking
Migration times in a capillary zone electropherogram obtained by using the field enhanced sample stacking technique are strongly affected by the injected sample volume. That is, the migration times significantly decrease with the increase of the sample volume. To avoid inaccurate qualitative analysis due to the above phenomena, the time axis of the electropherograms was converted into an effective mobility axis using our conversion method taking account of the temperature increase in the separation tube and relaxation of the potential gradient of the separation field. After the conversion, accurate qualitative analysis was possible in spite of drastic change of the migration time, suggesting our conversion method could be successfully used for the standardization of electropherograms obtained even by using the stacking effect. The cause of the decrease of the migration time in the stacking process was briefly discussed. 相似文献
90.
The geometric structures and isomeric stabilities of various stationary points in C(2)H(2)Si neutral and its cation and anion are investigated at the coupled-cluster singles, doubles (triples) [CCSD(T)] level of theory. For the geometrical survey, the basis sets used are of the Dunning's correlation consistent basis sets of triple-zeta quality (cc-pVTZ) for the neutral and cation. For the anions, the cc-pVTZ basis sets with diffuse functions (aug-cc-pVTZ) are used. The final energies are calculated by the use of the CCSD(T) level of theory with the aug-cc-pVTZ basis set at their optimized geometries. To lower lying neutrals and cations, the Dunning's correlation consistent basis sets of quadruple-zeta quality (cc-pVQZ) are also applied. Both the global minima of the C(2)H(2)Si neutral and cation, N-1 (C(2v):(1)A(1)) and C-1 (C(2v):(2)B(2)), respectively, are silacyclopropenylidene conformers, having a CCSi ring with a C[Double Bond]C double bond. No competitive stable isomers exist in the present C(2)H(2)Si neutral. In the cation, however, the second lowest lying isomer C-2 lies 10.8 kJ/mol above the most stable C-1. The vertical and adiabatic ionization potentials from the lowest lying neutral N-1 are 9.83 and 8.97 eV, respectively, at the CCSD(T)/cc-pVQZ level of theory. The electron addition to the N-1 does not result in the anion with positive (real) electron affinities. On the other hand, the electron addition to the N-2 isomer produces the global minimum anion A-1 (C(2v):(2)B(1)) with the positive electron affinities of 1.13 eV. The second lowest lying anion isomer A-2 with silylenylacetylene conformer, produced from an electron addition to the N-3 neutral, very well competes with the A-1 after the zero-point vibrational energy corrections. The energy difference between the two lowest lying isomers of the neutral and its anion, N-1 and A-1, is only 0.39 eV. 相似文献