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201.
A. M. Blokhin D. L. Tkachev 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》2010,50(1):849-864
We prove the local-in-time well-posedness of the initial boundary value problem for a system of quasilinear equations. This system is used for finding numerical stationary solutions of the hydrodynamical model of charge transport in the silicon MESFET (metal semiconductor field effect transistor). The initial boundary value problem has the following peculiarities: the quasilinear system is not a Cauchy-Kovalevskaya-type system; the boundary is a non-smooth curve and has angular points; nonlinearity of the problem is mainly connected with squares of gradients of the unknown functions. By using a special representation for the solution of a model problem we reduce the original problem to an integro-differential system. The local-in-time existence of a weakened generalized solution of this system is then proved by the fixed-point argument. 相似文献
202.
Under study are the stationary solutions of the mathematical model describing nonisothermal electroconvection of a weakly conducting polymeric liquid in the channel between two coaxial cylinders. 相似文献
203.
Zhukov A. E. Moiseev E. I. Kryzhanovskaya N. V. Blokhin S. A. Kulagina M. M. Guseva Yu. A. Mintairov S. A. Kalyuzhnyy N. A. Mozharov A. M. Zubov F. I. Maximov M. V. 《Semiconductors》2019,53(8):1099-1103
Semiconductors - Microdisk lasers 10–30 μm in diameter operating at room temperature without thermal stabilization and with an active region based on nanostructures of hybrid... 相似文献
204.
Nuclear and physical properties (activation and transmutation of elements) of BN and Al2O3 dielectric materials subjected to neutron irradiation for up to 5 years in Russian fast (BN-600) and fusion (DEMO-S) reactors were calculated using the ACDAM-2.0 software complex for different post-irradiation cooling times (up to 10 years). Analytical relations were derived for the calculated quantities. The results may be used in the analysis of properties of irradiated dielectric materials and may help establish the rules for safe handling of these materials. 相似文献
205.
We study the classical problem of a supersonic stationary flow of a nonviscous nonheat-conducting gas in local thermodynamic equilibrium past an infinite plane wedge. Under the Lopatinski? condition on the shock wave (neutral stability), we prove the well-posedness of the linearized mixed problem (the main solution is a weak shock wave), obtain a representation of the classical solution, where, in this case (in contrast to the case of the uniform Lopatinski? condition—an absolutely stable shock wave), plane waves additionally appear in the representation. If the initial data have compact support, the solution reaches the given regime in infinite time. 相似文献
206.
207.
A. V. Babichev N. V. Kryzhanovskaya E. I. Moiseev A. G. Gladyshev L. Ya. Karachinsky I. I. Novikov S. A. Blokhin M. A. Bobrov Yu. M. Zadiranov S. I. Troshkov A. Yu. Egorov 《Semiconductors》2017,51(9):1127-1132
The possibility of fabricating hybrid metamorphic heterostructures for vertical-cavity surfaceemitting lasers working in the 1300-nm spectral range is demonstrated. The metamorphic semiconductor part of the heterostructure with a GaAs/AlGaAs distributed Bragg reflector and an active region based on InAlGaAs/InGaAs quantum wells is grown by molecular-beam epitaxy on a GaAs (100) substrate. The top dielectric mirror with a SiO2/Ta2O5 distributed Bragg reflector is formed by magnetron sputtering. The spectra of the room-temperature microphotoluminescence of these vertical-cavity surface-emitting laser heterostructures are studied under 532-nm excitation in the power range of 0–70 mW (with a focused-beam diameter of ~1 μm). The superlinear dependence of the photoluminescence intensity on the excitation power, narrowing of the photoluminescence peaks, and a change in the modal composition may be indications of lasing. The results obtained give evidence that the technology of the metamorphic growth of heterostructures on GaAs substrates can be used for the fabrication of vertical-cavity surface-emitting lasers working in the 1300- nm spectral range. 相似文献
208.
Alina Amirova Anastasiya Tobolina Tatyana Kirila Alexey Blokhin Alla Razina Andrey Tenkovtsev 《International Journal of Polymer Analysis and Characterization》2018,23(3):278-285
New thermoresponsive star-shaped poly(2-isopropyl-2-oxazoline) (PiPrOx) and poly(2-ethyl-2-oxazoline) (PEtOx) with arm grafting to upper rim of calix[8]arene core were synthesized and studied in aqueous solutions by light scattering and turbidimetry methods. The solution behavior was compared with that for polyoxazoline stars with varying positions of arm grafting, i.e., to lower rim of calix[8]arene. The observed growth of the phase separation temperature for PiPrOx as compared to PEtOx is explained by different dehydration temperatures of ethyl- and isopropyloxazoline units. The phase separation temperatures decrease after the changeover from lower rim grafting to upper rim one due to varying configurations of calix[8]arene. 相似文献
209.
N. V. Kryzhanovskaya M. V. Maximov S. A. Blokhin M. A. Bobrov M. M. Kulagina S. I. Troshkov Yu. M. Zadiranov A. A. Lipovskii E. I. Moiseev Yu. V. Kudashova D. A. Livshits V. M. Ustinov A. E. Zhukov 《Semiconductors》2016,50(3):390-393
Microdisk injection lasers on GaAs substrates, with a minimum diameter of 15 μm and an active region based on InAs/InGaAs quantum dots, are fabricated. The lasers operate in the continuous-wave mode at room temperature without external cooling. The lasing wavelength is around 1.27 μm at a minimum threshold current of 1.6 mA. The specific thermal resistance is estimated to be 5 × 10–3 °C cm2/W. 相似文献
210.
Kryzhanovskaya N. V. Blokhin S. A. Maximov M. V. Nadtochy A. M. Zhukov A. E. Fedorova K. V. Ledentsov N. N. Ustinov V. M. Il’inskaya N. D. Bimberg D. 《Semiconductors》2011,45(7):962-965
Effect of parameters of the AlGaAs-(AlGa)
x
O
y
layer forming the pedestal of a microdisk laser with an active region based on InAs/InGaAs quantum dots on specific features
of the emission spectrum at a temperature of 15 K under optical excitation has been studied. A decrease in the oxidation depth
of the Al0.97Ga0.03As layer results in a decrease in the intensity of “whispering gallery mode” lines; simultaneously, the lasing threshold becomes
higher and the Q factor is diminished by increased leakages into the substrate region. 相似文献