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1.
We present conditions for the invertibility of Markov chains with values from + and general measure of irreducibility. The results are obtained by the classical method of test functions combined with the method of perturbation of partial potentials.Translated from Ukrainskyi Matematychnyi Zhurnal, Vol. 56, No. 5, pp. 705–712, May, 2004. 相似文献
2.
V. A. Pushkarchuk S. Ya. Kilin A. P. Nizovtsev A. L. Pushkarchuk V. E. Borisenko C. von Borczyskowski A. B. Filonov 《Optics and Spectroscopy》2005,99(2):245-256
The electronic and spin properties of different nanocrystals of carbon are studied. The properties of these cluster systems are modeled in terms of the ab initio (Hartree-Fock) and semiempirical (PM3, AM1) quantum-chemical methods. The calculations are performed for different carbon nanocluster systems: defect-free and with [NV]? centers, hydrogen passivated (C38H42, C71H84, C86H78), and with a free (unpassivated) surface (C38, C71, C86). The spin properties of unhydrated nanoclusters were studied for the first time. The structure of all the clusters under study was optimized using the total energy minimization principle. It is shown that, in the case of hydrated carbon nanocrystals passivated by hydrogen atoms, diamond-like clusters are formed. The atomic structure of an unpassivated nanocrystal depends on the number of atoms in the cluster, as well as on its initial geometrical parameters. In some cases, clusters with a fullerene-like surface are formed. In hydrogenpassivated diamond nanocrystals with [NV]? centers, the spin density is localized at the nuclei of C atoms nearest to the center vacancies. For the unpassivated counterparts, the spin density is localized at the nuclei of C atoms forming the surface of the corresponding nanocrystal. 相似文献
3.
We have studied the deep levels in gallium arsenide implanted with oxygen ions at a low dose of 2·1010 cm−2 and the influence of those levels on the current-voltage characteristics of Ni/Pd/Ga Schottky-barrier structures. The deep
levels were checked by the thermally-stimulated-current (TSC) method. The number of peaks on the TSC curves and their amplitudes
are shown to depend on the oxygen-ion energy and the temperature of the post-implantation anneal. An important role in the
formation of centers associated with oxygen is played by gallium diffusion into the protective SiO2/Si3N4 insulator layer as well as by elastic and plastic strain phenomena that occur during deposition of the coating and post-implantation
annealing of the specimens. The deep levels due to oxygen are responsible for the appearance of excess currents resulting
from recombination as well as for ohmic leakages.
V. D. Kuznetsov Siberian Physicotechnical Institute at Tomsk State University. Translated from Izvestiya Vysshikh Uchebnykh
Zavedenii, Fizika, No. 5, pp. 30–36, May, 1996. 相似文献
4.
5.
N. Filonov 《Communications in Mathematical Physics》2003,240(1-2):161-170
The periodic Maxwell operator is considered. Piecewise constant coefficients are constructed in such a way that the spectrum of operator has the gaps. 相似文献
6.
The Dirichlet and Neumann problems for the Laplace operator in a bounded domain in Euclidean space are considered. Some estimates
of the difference N
N(λ) - N
D(λ) of counting functions are discussed. 相似文献
7.
NL Asfandiarov AI Fokin VG Lukin EP Nafikova GS Lomakin VS Fal'ko YV Chizhov 《Rapid communications in mass spectrometry : RCM》1999,13(12):1116-1123
A series of anthraquinone (C(14)O(2)H(8)) derivatives has been studied by means of electron capture negative ion mass spectrometry (ECNI-MS), photoelectron spectroscopy (PES), and AM1 quantum chemical calculations. Mean lifetimes of molecular negative ions M(-.) (MNI) have been measured. The mechanism of long-lived MNI formation in the epithermal energy region of incident electrons has been investigated. A simple model of a molecule (a spherical potential well with the repulsive centrifugal term) has been applied for the analysis of the energy dependence of cross sections at the first stage of the electron capture process. It has been shown that a temporary resonance of MNI at the energy approximately 0.5 eV corresponds to a shape resonance with lifetime 1-2.10(-13) s in the f-partial wave (l = 3) of the incident electron. The next resonant state of MNI at the energy approximately 1.7 eV has been associated with the electron excited Feshbach resonance (whose parent state is a triplet npi* transition). In all cases the initial electron state of the MNI relaxes into the ground state by means of a radiationless transition, and the final state of the MNI is a nuclear excited resonance with a lifetime measurable on the mass spectrometry timescale. Copyright 1999 John Wiley & Sons, Ltd. 相似文献
8.
An attempt is made to explain the shape of the curved steps at the (010) face of orthorhombic lysozyme crystals and to determine the density, the rate of formation, and the velocity of kinks. The interpretation is performed in terms of the concepts developed in studies on the crystallization of long-chain polymers within the Frank model. It is demonstrated that this model is incorrectly generalized to the case of high kink densities. A algorithm for determining the coordinates of the growth front in images obtained with atomicforce microscopes is proposed and implemented. 相似文献
9.
K. N. Filonov V. N. Kurlov N. V. Klassen E. A. Kudrenko E. A. Shteinman 《Bulletin of the Russian Academy of Sciences: Physics》2009,73(10):1374-1376
A new method has been developed for obtaining various versions of nanostructured SiC films and coatings, whose structure can
be altered in a controlled way for different applications. The films and coatings obtained can be useful in metallurgy, nuclear
power industry, microelectronics, and high-temperature furnaces. 相似文献
10.
The time of switching, step length and delay time of a discharge were investigated in this present project, under the following experimental conditions: plain brass electrodes, two- to 20-fold overvoltage and air pressure 30 mm Hg. In addition, the relative intensity of bremsstrahlung from the anode was measured and the-quanta energy was determined by the radiation attenuation method in aluminum plates. It is suggested that such short delay times obtained can be explained first of all by the accelerated motion of electrons and secondly by the bremsstrahlung from the anode.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 1, pp. 61–65, January, 1973. 相似文献