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71.
A. El Allati  Y. Hassouni  N. Metwally 《中国物理 B》2011,20(11):110303-110303
The dynamics of the maximum entangled coherent state traveling through an amplitude damping channel is investigated. For small values of the transmissivity rate, the traveling state is very fragile to this noise channel, which suffers from the phase flip error with high probability. The entanglement decays smoothly for larger values of the transmissivity rate and speedily for smaller values of this rate. As the number of modes increases, the traveling state over this noise channel quickly loses its entanglement. The odd and even states vanish at the same value of field intensity.  相似文献   
72.
Powder iron has been bombarded by a 5 keV Kr+ ions in a vacuum better than 10-7 torr and under few 10-6 torr ultra pure oxygen partial pressure. The optical spectra of the sputtered particles were recorded between 340.0 nm and 410.0 nm. These spectra exhibit discrete lines, which are attributed to neutral excited atoms of iron. Two iron oxides, namely hematite (Fe2O3)_{3}) and magnetite (Fe3O4)_{4}), in powder form, were studied under the same experimental conditions and identical lines were observed in the obtained spectra. The absolute intensities of the spectral lines in all spectra were measured and the differences in the recorded yield photons were discussed in term of electron-transfer processes between the excited sputtered atom and the bombarded surface. In accordance with the proposed interpretation, we suggest values for the energy gaps and electronic affinities for the studied oxides and for the oxide layer that might be formed by the adsorption of oxygen atoms.  相似文献   
73.
Zn x Cd1–x S thin films (0x0.20) were prepared using rf sputtering in argon atmosphere and characterized using X-ray diffraction, optical transmission, electrical resistivity and photoconductive decay measurements. The films were found to possess hexagonal structure. The crystallite size and degree of preferential orientation were found to decrease with the increase ofx and to improve upon annealing in vacuum at 250 °C. The transmission edge shifted towards shorter wavelengths with the increase ofx in agreement with the expected shift in the energy band gap. The films were found to exhibit room temperature resistivity in the range 100–1000 cm. The obtained values of long wavelength transmission (70–80%) and minority carrier diffusion length (30 m) are high enough for the application of these films in the field of solar cells.  相似文献   
74.
Scatterometry is a well established technique currently utilized in research, as well as in industrial applications, to retrieve the properties of a given scatterer (the target) by looking at how the light coming from a certain source is diffracted in the far field. Currently the light source is often a discharge lamp that, after wavelength filtering, can be thought as a quasi-monochromatic, but spatially incoherent, source. In the present work, benefits of using a focused spot from a spatially coherent light source, as that emitted by a laser, are investigated on a theoretical viewpoint. The focused spot is scanned over the object of interest and, for each scan position, a far-field diffraction pattern is recorded. Our results show that spatially coherent light can sensibly increase the accuracy of the technique with respect to the target’s geometrical profile.  相似文献   
75.
In this paper, we have addressed the problem of the radiation transport with the Monte Carlo N particle(MCNP) code. This is a general purpose Monte Carlo tool designed to transport neutron, photon and electron in three dimensional geometries. To examine the performance of MCNP5 code in the field of external radiotherapy, we performed the modeling of an Electron Density phantom (EDP) irradiated by photons from 60Co source. The model was used to calculate the Percent Depth Dose (PDD) at different depths in an EDP. One field size for PDD has been examined. A 60Co photons source placed at 80 cm source to surface distance (SSD). The results of calculations were compared to TPS data obtained at National Institute of Oncology of Rabat.  相似文献   
76.
A high resolution (0.0018 cm−1) Fourier transform instrument has been used to record the spectrum of an enriched 34S (95.3%) sample of sulfur dioxide. A thorough analysis of the ν2, 2ν2 − ν2, ν1, ν1 + ν2 − ν2, ν3, ν2 + ν3 − ν2, ν1 + ν2 and ν2 + ν3 bands has been carried out leading to a large set of assigned lines. From these lines ground state combination differences were obtained and fit together with the existing microwave, millimeter, and terahertz rotational lines. An improved set of ground state rotational constants were obtained. Next, the upper state rotational levels were fit. For the (0 1 0), (1 1 0) and (0 1 1) states, a simple Watson-type Hamiltonian sufficed. However, it was necessary to include explicitly interacting terms in the Hamiltonian matrix in order to fit the rotational levels of the (0 2 0), (1 0 0) and (1 0 1) states to within their experimental accuracy. More explicitly, it was necessary to use a ΔK = 2 term to model the Fermi interaction between the (0 2 0) and (1 0 0) levels and a ΔK = 3 term to model the Coriolis interaction between the (1 0 0) and (0 0 1) levels. Precise Hamiltonian constants were derived for the (0 0 0), (0 1 0), (1 0 0), (0 0 1), (0 2 0), (1 1 0) and (0 1 1) vibrational states.  相似文献   
77.
We present new measurements of electron scattering from high-momentum nucleons in nuclei. These data allow an improved determination of the strength of two-nucleon correlations for several nuclei, including light nuclei where clustering effects can, for the first time, be examined. The data also include the kinematic region where three-nucleon correlations are expected to dominate.  相似文献   
78.
The apparently universal 1‐bond → 2‐mode percolation behavior in the Raman spectra of zincblende semiconductor alloys is generally observed for the short bond only, and not for the long one. In this work we perform a combined high‐pressure‐backward/near‐forward Raman study of the leading percolation‐type (Zn,Be)Se alloy (~50 at.% Be), which exhibits a distinct percolation doublet in the spectral range of its short Be―Se bond, in search of a Zn―Se analogue. The high‐pressure‐backward insight is not conclusive per se, but clarifies the perspective behind the near‐forward Raman study. The latter reveals an unique Zn―Se phonon–polariton. Its fair contour modeling depending on the scattering angle is achieved within the linear dielectric approach, based on ellipsometry measurement of the ZnBeSe refractive index. Somewhat surprisingly this reveals that the phonon–polariton in question is a ‘fractional’ one in that it carries only half of the available Zn―Se oscillator strength, as ideally expected in case of a BeSe‐like bimodal Raman behavior of the long Zn―Se bond. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
79.
Recently, electron energy distribution function (EEDF) extraction techniques have been evaluated using regularized solutions to the integral problem. These techniques do not assume any mathematical representation of the EEDF and solve the integral problem for any function that best represents the EEDF. Also, unlike the more widely used point-by-point extraction of the second-derivative relationship, the integrated relationship between electron current and the EEDF is used, instead of a relatively small fraction of the integrated data in the point-by-point method. In this paper, the electron current for an arbitrary distribution function is derived, assuming that the distribution is a sum of step functions representing such a function. This technique for EEDF extraction is validated by adding noise to numerically generated data and using a regularized least squares (RLS) method to calculate the original function by solving for the individual step function contribution to the total electron current. Comparisons are then made between the expected and the reconstructed solution to evaluate its accuracy with respect to EEDF reconstruction and integrated normalization of the electron density.   相似文献   
80.
We suggest theoretically the possibility to transmit information through a decohering quantum channel employing Glauber’s coherent states. In fact, we study the dynamics of quantum correlations of two-mode entangled bipartite coherent states in the presence of the amplitude damping effect. In addition, we examine the quantum correlations based on quantum discord, which is a powerful key source in quantum information processing.  相似文献   
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