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51.
Characterization by Auger electron spectroscopy (AES) and Fourier transformation infrared spectroscopy (FTIR) confirms (Ta2O5)x(Al2O3)1−x alloys are homogeneous pseudo-binary alloys with increased thermal stability with respect to end member oxides, Ta2O5 and Al2O3. Capacitance–voltage (C–V) and current density–voltage (J–V) data as a function of temperate show that the Ta d-states of the alloys act as localized electron traps, and are at an energy approximately equal to the conduction band offset of Ta2O5 with respect to Si. 相似文献
52.
Z. -Q. Fang D. C. Look R. Chandrasekaran S. Rao S. E. Saddow 《Journal of Electronic Materials》2004,33(5):456-459
Porous SiC (PSC) has been proposed as a buffer layer for reducing defects in epitaxial SiC layers. In this study, electrical
characteristics of a 6H-SiC epitaxial layer grown by chemical vapor deposition on a porous SiC substrate (SiC-on-PSC) have
been compared to those simultaneously grown on a standard SiC substrate (SiC-on-STD). Schottky barrier diodes (SBDs) have
been fabricated on both epitaxial layers and then investigated with temperature-dependent current-voltage (I-V), capacitance-voltage
(C-V), and deep-level transient spectroscopy (DLTS) measurements. The SBDs on both SiC-on-PSC and SiC-on-STD show about the
same I-V and C-V characteristics, and at least four electron traps, i.e., B (0.75 eV), C (0.63 eV), D (0.40 eV), and E (0.16
eV), can be identically found in both SBDs by DLTS measurements. Thus, we conclude that the electrical quality of SiC-on-PSC
is comparable to that of SiC-on-STD, and that the higher breakdown voltages observed in SBDs on SiC-on-PSC are not obviously
related to a different defect structure. 相似文献
53.
The survival probability of a particle which moves according to a biased random walk in a one-dimensional lattice containing randomly distributed deep traps is studied at large times. Exact asymptotic expansions are deduced for fields exceeding a certain threshold, using the method of images. In order to cover the whole range of fields, we also derive the behavior of the survival probability below this threshold, using the eigenvalue expansion method. The connection with the continuous diffusion model is discussed. 相似文献
54.
Calcium sulphate phosphors activated with samarium as an impurity with various percentage composition have been prepared and
their fluorescence rise and phosphorescence decay behaviours have been studied. The growth curve is investigated to study
the density of traps. The process of filling of traps during x-ray excitation is revealed. The decay curves are analysed to
study the distribution of traps, the nature of decay and kinetics involved in the luminescence process. The concentration
dependence of fluorescence emission of the phosphors is also discussed. 相似文献
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An improved hot carrier injection (HCI) degradation model was proposed based on interface trap generation and oxide charge injection theory. It was evident that the degradation behavior of electric parameters such as Idlin, Idsat, Gm and Vt fitted well with this model. Devices were prepared with 0.35μm technology and different LDD processes. Idlin and Idsat after HCI stress were analyzed with the improved model. The effects of interface trap generation and oxide charge injection on device degradation were extracted, and the charge injection site could be obtained by this method. The work provides important information to device designers and process engineers. 相似文献
59.
Dmytro Shyshlov 《Molecular physics》2013,111(14):1912-1925
We report a rigorous computational treatment of quantum dynamics of cold ions in a double-well trap using the time-dependent Schrödinger equation. Our method employs a numerically accurate approach that avoids approximations, such as assumption of weak coupling between the wells; normal mode nature of vibrations; or harmonic approximation for energy spectrum of the double-well system. Our goal is to reproduce, from first principles, the process of energy swaps between the wells observed in the experiments at NIST [Nature 471, 196 (2011)] and Innsbruck [Nature 471, 200 (2011)]. The model parameters and the initial conditions are carefully chosen to mimic experimental conditions. We obtain accurate energies and wave functions of the system numerically, and study the evolution of motional wave packets to provide new insight. This model reproduces experimental results obtained by NIST and Innsbruck in detail. We explain the energy transfer in terms of wave packet dynamics in the asymmetric potential energy well. We also show that, for a localised initial wave packet, this phenomenon can be interpreted using the terms of classical dynamics, such as trajectory of motion governed by the well-known simple principle: the angle of reflection equals the angle of incidence. 相似文献
60.
N. Shashank Vikram Singh Sanjeev K. Gupta K. V. Madhu J. Akhtar R. Damle 《辐射效应与固体损伤》2013,168(4):313-322
Ni/SiO2/Si MOS structures were fabricated on n-type Si wafers and were irradiated with 50 MeV Li3+ ions with fluences ranging from 1×1010 to 1×1012 ions/cm2. High frequency C–V characteristics are studied in situ to estimate the build-up of fixed and oxide charges. The nature of the charge build-up with ion fluence is analyzed. Defect levels in bulk Si and its properties such as activation energy, capture cross-section, trap concentration and carrier lifetimes are studied using deep-level transient spectroscopy. Electron traps with energies ranging from 0.069 to 0.523 eV are observed in Li ion-irradiated devices. The dependence of series resistance, substrate doping and accumulation capacitance on Li ion fluence are clearly explained. The study of dielectric properties (tan δ and quality factor) confirms the degradation of the oxide layer to a greater extent due to ion irradiation. 相似文献