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151.
152.
A method is presented for the analysis of single degree of freedom non-linear oscillators characterized by second order non-linear ordinary differential equations containing a parameter ε which need not be small. The method is based on expanding the solution as a sine power series. We explain our results as an application to the Duffing oscillators. 相似文献
153.
The ESR method is used to study the oxidation kinetics of the CH3, C2H5, n-C4H9, i-C4H9, s-C4H9, t-C4H9, n-C6H13, C6H11, C6H5CH2, CH3C6H4CH2, and C6H5CH2CH2 radicals in methanol matrix at 87 K. The reaction kinetics are shown to be describable in terms of a time-dependent rate constant k(t). The contribution from the matrix relaxation to k(t) has been determined. The oxidation rate and the shape of the kinetic curve are independent of the type of the radical. Models interpreting the experimental data are discussed. 相似文献
154.
155.
In this paper, we investigate the BTZ black hole in P-V critical point of view. As we know, the BTZ black hole does not have P-V critical behavior. So in this case, we introduce some anstaz that give us the modified BTZ black hole. Finally, we show that this modified BTZ black hole is satisfied by the equation of state of Liquid-gas phase transition. 相似文献
156.
157.
The apparent molar volume and apparent molar isentropic compressibility of solutions of sodium di-hydrogen phosphate (NaH2PO4) in (1-propanol + water) mixed-solvent media with alcohol mass fractions of 0.00, 0.05, 0.10, and 0.15 are reported over the range of temperature (283.15 to 303.15) K at 5 K intervals. The results were fitted to a Redlich–Mayer type equation from which the apparent molar volume and apparent molar isentropic compressibility of the solutions at the infinite dilution were also calculated at the working temperature. The results show a positive transfer volume of NaH2PO4 from an aqueous solution to an aqueous 1-propanol solution. The apparent molar isentropic compressibility of NaH2PO4 in aqueous 1-propanol solutions is negative and it increases with increasing the concentration of NaH2PO4, 1-propanol, and temperature. Electrical conductivity and refractive index of the solutions are also studied at T = 298.15 K. The effects of the electrolyte concentration and relative permittivity of the medium on the molar conductivity were also investigated. 相似文献
158.
S. M. Sadeghi 《Journal of nanoparticle research》2016,18(2):46
We investigate formation of unique quantum states (metastates) in quantum dot-metallic nanoparticle systems via self-induced coherent dynamics generated by interaction of these systems with a visible and an infrared laser fields. In such metastates, the quantum decoherence rates of the quantum dots can become zero and even negative while they start to rapidly change with time. Under these conditions, the energy dissipation rates and plasmon fields of the nanoparticle systems undergo undamped oscillations with gigahertz frequency, while the amplitudes of both visible and the infrared laser fields are considered to be time-independent. These dynamics also lead to variation of the plasmon absorption of the metallic nanoparticles between high and nearly zero values, forming electromagnetically induced transparency oscillations. We show that under these conditions, the effective transition energies and broadening of the quantum dots undergo oscillatory dynamics, highlighting the unique aspects of the metastates. These results extend the horizon for investigation of light-matter interaction in the presence of zero or negative polarization dephasing rates with strong time dependency. 相似文献
159.
The diffusioosmosis of an electrolyte solution inside a uniformly charged rectangular channel at steady locally developed conditions is the subject of this study. Utilizing a finite element based numerical procedure, we try to estimate the errors incurred by modeling the actual rectangular geometry of typical microchannels as a slit. We demonstrate that the flow pattern and direction are generally dependent upon the width‐to‐height ratio of the channel. Such a finding, besides showing the ineffectiveness of the slit geometry in representing a rectangular channel of small aspect ratio, informs us of another mechanism of controlling the diffusioosmotic flow. Inspections of the mean velocity reveal that, although it drastically grows by increasing the aspect ratio at smaller values of this parameter, no significant change is observed when the aspect ratio is 5 or higher. The same trend is observed when EDL is shrunk and is considered as a basis for the introduction of a slip‐like velocity, similar to the concept of the Helmholtz–Smoluchowski electroosmotic velocity, which will be of high practical importance when dealing with a micronsized channel. Because of its significance, an expression is presented for this slip velocity utilizing the curve fitting of the results, assuming a typical Peclet number. 相似文献
160.
Rostampour Malihe Aboudzadeh Mohammadreza Sadeghi Mahdi Hamidi Saeid Alirezapour Behroz Soltani Naser Aslani Gholamreza 《Journal of Radioanalytical and Nuclear Chemistry》2017,314(3):1759-1766
Excitation functions and theoretical yields via charge particle induced reactions were evaluated using EMPIRE-3.2.2 and ALICE/ASH codes and the obtained results have been discussed and compared with the available reported experimental data. It has been verified that natCu(p,n)65Zn reaction is the optimum 65Zn production route. The 65Zn was produced using natCu(p,xn) 65Zn reaction in the energy range of 16.8 → 12.2 MeV with the thick target yield of 0.15 ± 0.005 MBq/μA h. The 65Zn radionuclide was purified by anion exchange chromatography.
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