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111.
陶瓷过滤器高温除尘技术的研究进展 总被引:2,自引:0,他引:2
对陶瓷过滤元件及结构、滤饼的作用和架桥、过滤器故障安全(CPP)系统及陶瓷过滤器高温气体净化一体化技术等几个方面进行了评述,总结了陶瓷过滤器存在着过滤管破裂、清灰效率下降、管板和器壁的连接及脉冲阀的长期稳定性等几个问题,指出新型陶瓷材料的研究和陶瓷过滤器高温气体净化一体化技术是陶瓷过滤器今后的研究方向. 相似文献
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The equations for quantum ballistic transport in inhomogeneous quantum wire structures are transformed into a set of one-dimensional coupled mode equations where the coupling parameters are explicitly dependent on the shape parameters for the confinement potential. In the adiabatic approximation or in the extreme quantum limit the resulting motion is governed by an effective Hamiltonian which contains the influence of quasi-electric fields and quasi-momentum dependent forces which arise from the inhomogeneous shape parameter variation along the quantum waveguide. The subsequent transport may be described by a Boltzmann-like kinetic equation and hot-electron effects arising from variations in the waveguide profile are predicted. It is shown that transport through a wide region of an otherwise narrow wire leads to multiply-connected electron paths which will produce Aharonov-Bohm resonances. The analytical formalism is underpinned by a new numerical method suitable for 3-D studies based on representing the inhomogeneous waveguide by an equivalent network of one-dimensional wires. 相似文献
115.
Zhen Yu Yuping Duan Lidong Liu Shunhua Liu Xujing Liu Xiaogang Li 《Surface and interface analysis : SIA》2009,41(5):361-365
Hot‐dipped aluminum copper with plating auxiliary KF is introduced in this work. In this study, the intermetallic layer thickness varies with dipping temperature and time in a linear relationship. The main phases are identified to be CuAl2 and K3AlF6 by means of X‐ray diffraction. The reaction equations are deduced according to the elements concentration gradient in cross section. The copper diffusion rate in liquid Al is calculated to be 1.13 × 10−12 m2/s by Fick's second law in semi‐infinite solid model, and the obtained conductivity is 1.758–1.767 × 10−2 Ω mm2/m. The results indicate that the interfacial bonding is in a good state and plating auxiliary KF aqueous solution. can significantly improve the substrate wettability. The appropriate hot‐dipping condition for the samples is 953–973 K for 4–8 s. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
116.
To improve the wear resistance of polytetrafluoroethylene (PTFE), a crosslinked aromatic thermosetting polyester (ATSP) has been blended directly with PTFE. Cured ATSP powder which was directly synthesized as a cured powder form was used for this application. Because of the similar processing temperature range of cured ATSP and PTFE, composites within the entire composition range were successfully prepared by blending these two powders using a hot press. Tribological pin‐on‐disk tests (composite pins sliding against gray cast iron disks) showed improvement on friction coefficient of all composites and much less wear than pure PTFE. The composites survived at contact pressures of 7 MPa, which is higher than either pure PTFE or pure ATSP could sustain. With an increase in the amount of ATSP in the composites, storage modulus, and glass transition temperature were higher, and the wear resistance was enhanced. SEM images helped provide explanations for the unusually low mean wear rates that were observed for these composite samples. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
117.
E. Schll 《Solid-state electronics》1989,32(12):1129-1135
The status of our theoretical understanding of self-generated nonlinear and chaotic oscillations in semiconductors associated with impact ionization of impurity centers is reviewed from the viewpoint of hot electron transport theory. A set of hydrodynamic balance equations for the carrier density, mean momentum and energy is developed. It constitutes, together with Maxwell's equations, a macroscopic nonlinear dynamic system. We discuss various simplified versions of this model, which give rise to local or global bifurcations and hysteresis of limit cycle oscillations, a period-doubling route to chaos, mode-locking and quasiperiodicity, traveling waves, and breathing current filaments. 相似文献
118.
L. Rota
P. Lugli
《Solid-state electronics》1989,32(12):1423-1427The theoretical treatment of electron-electron (e-e) scattering in semiconductor transport has always posed formidable problems, due to the long range and to the non-linearity of the interaction. Here we present a Monte Carlo study of the e-e interaction based on a molecular-dynamics approach. The full long range of the Coulomb interaction is accounted for, and no assumptions are needed on the screening process. This is particularly important when different valleys are involved, and a multi-component plasma has to be simulated. The Monte Carlo algorithm is applied to the study of the relaxation of photo-excited electrons in GaAs looking in particular at the energy exchange between electrons in different valleys. Such type of interaction has never been considered up to now in Monte Carlo simulations. The dependence of the e-e interaction on the electron density is discussed in detail. A comparison with a different approach, that treats the e-e scattering in k-space using a screened potential formulation, is also presented. 相似文献
119.
Uniform carrier injection into the channel of n-MOSFETs generates two types of interface states, depending on the oxide electric field: One is linearly proportional to the injected electron density (Type I), while the other shows a half-power dependence (Type II). Charge-pumping measurements in the temperature range of 77K and 263K show that the type I interface states are located in the mid-gap, while the type II interface states are uniformly distributed in wide energy range. Holes generated at the gate/SiO2 interface or in the oxide are found to be responsible for the type I interface states, while hydrogen or hydrogen compounds diffusing from the interface cause the type II interface states. 相似文献
120.
Hamidreza Esmaielpour Vincent R. Whiteside Jinfeng Tang Sangeetha Vijeyaragunathan Tetsuya D. Mishima Shayne Cairns Michael B. Santos Bin Wang Ian R. Sellers 《Progress in Photovoltaics: Research and Applications》2016,24(5):591-599
InAs/AlAsxSb1 − x quantum wells are investigated for their potential as hot carrier solar cells. Continuous wave power and temperature‐dependent photoluminescence indicate a transition in the dominant hot carrier relaxation process from conventional phonon‐mediated carrier relaxation below 90 K to a regime where inhibited radiative recombination dominates the hot carrier relaxation at elevated temperatures. At temperatures below 90 K, photoluminescence measurements are consistent with type‐I quantum wells that exhibit hole localization associated with alloy/interface fluctuations. At elevated temperatures, hole delocalization reveals the true type‐II band alignment, where it is observed that inhibited radiative recombination due to the spatial separation of the charge carriers dominates hot carrier relaxation. This decoupling of phonon‐mediated relaxation results in robust hot carriers at higher temperatures, even at lower excitation powers. These results indicate type‐II quantum wells offer potential as practical hot carrier systems. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献