全文获取类型
收费全文 | 221篇 |
免费 | 0篇 |
专业分类
化学 | 50篇 |
力学 | 3篇 |
数学 | 58篇 |
物理学 | 110篇 |
出版年
2022年 | 4篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 9篇 |
2017年 | 9篇 |
2016年 | 9篇 |
2015年 | 3篇 |
2014年 | 6篇 |
2013年 | 8篇 |
2012年 | 8篇 |
2011年 | 9篇 |
2010年 | 10篇 |
2009年 | 8篇 |
2008年 | 5篇 |
2007年 | 4篇 |
2006年 | 4篇 |
2005年 | 11篇 |
2004年 | 4篇 |
2003年 | 10篇 |
2002年 | 4篇 |
2001年 | 8篇 |
2000年 | 2篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 5篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 2篇 |
1989年 | 3篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 5篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 2篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 2篇 |
1974年 | 1篇 |
1973年 | 2篇 |
1971年 | 2篇 |
1970年 | 4篇 |
1968年 | 5篇 |
1967年 | 5篇 |
1966年 | 4篇 |
1965年 | 2篇 |
1962年 | 1篇 |
排序方式: 共有221条查询结果,搜索用时 46 毫秒
1.
The lattice IR reflection spectra of a ZnTe/Zn0.8Cd0.2Te superlattice measured at temperatures of 300 and 10 K are analyzed. The ZnTe/Zn0.8Cd0.2Te superlattice is grown by molecular-beam epitaxy on a GaAs substrate with a ZnTe buffer layer. It is found that the lattice IR reflection spectra of the studied structure exhibit only one reflection band. Dispersion analysis of the experimental spectrum has revealed the presence of one lattice TO mode close in frequency to the mode of pure ZnTe. This result is explained by a shift in the frequency of the lattice modes of the ZnTe and Zn0.8Cd0.2Te layers of the superlattice toward each other. In turn, this shift is caused by internal elastic stresses in the superlattice due to a mismatch between the lattice parameters of the materials of these layers. 相似文献
2.
3.
ESR results are reported for solutions and glasses containing vanadyl diethyldithiophosphate, vanadyl and vanadium diethyldithiocarbamates, and vanadium butylxanthogenate. Comparison with compounds of known structure gives the structures of these complexes. 相似文献
4.
Andrei N. Kozyrev Andrei F. Mironov Jorge Davila Anthony Harriman 《Journal of heterocyclic chemistry》1988,25(3):885-889
The synthesis and characterisation of a C6 hydrocarbon linked porphyrin dimer and its zinc complex is described. From fluorescence quantum yields and excited singlet and triplet state lifetimes, recorded for the dimers and the corresponding monomer species, it is suggested that the dimeric porphyrins exist in solution in open and closed conformations. The open conformations retain photophysical properties similar to those of the relevant monomeric species but the closed conformations do not fluoresce. 相似文献
5.
S. P. Bugaev A. V. Kozyrev V. A. Kuvshinov N. S. Sochugov P. A. Khryapov 《Plasma Chemistry and Plasma Processing》1998,18(2):247-261
Oxidative conversion of a mixture of natural gas and oxygen in a barrier-discharge plasma-chemical reaction was investigated experimentally. The process was conducted at atmospheric pressure and room temperature. The discharge was initiated by high-voltage pulses of 50–100 s duration at a repetition frequency of up to 2 kHz. The principal feature of the process was that in the plasma-chemical reactor conditions were created which stimulated the condensation of the products of incomplete oxidation of methane that resulted in the formation of aerosol even from nonsaturated vapor. The removal of intermediate reagents from the gaseous phases into the aerosol prevented them from further oxidation. Depending on the experimental conditions, the mass percentage of the components of the condensate formed varied within the following limits: formic acid from 20 to 40%, methanol from 8 to 15%, methylformate from 4 to 8%, and water from 40 to 60%. The conversion process has been realized on a laboratory setup of average power up to 1 kW. In the single-pass mode, a 57% degree of conversion of the mixture has been achieved. The energy value of the condensate is 15–20 kWh/kg. 相似文献
6.
A. A. Dadykin A. G. Naumovets Yu. N. Kozyrev M. Yu. Rubezhanska P. M. Lytvyn Yu. M. Litvin 《Progress in Surface Science》2003,74(1-8):305-318
Monolayer and multilayer Ge nanocluster structures were prepared on Si(1 0 0) using molecular beam epitaxy. The cluster size was 10 nm and cluster density was 1010 cm−2. A stable field electron emission was obtained from these structures, showing current peaks in the current–voltage characteristics, which may be attributed to the resonant electron tunneling via the energy levels of the nanocluster potential well. For cluster multilayers, the current–voltage curves also showed current peaks with a complex shape. The cluster multilayer structures had a considerable temperature sensitivity, as well as photosensitivity, in the wavelength range from 0.4 to 10 μm. 相似文献
7.
V. F. Tarasenko E. Kh. Baksht A. G. Burachenko D. V. Beloplotov A. V. Kozyrev 《Doklady Physics》2016,61(11):539-542
Spectral and amplitude–time characteristics of PMMA radiation under the impact of runaway electrons with subnanosecond duration are studied. The PMMA radiation spectra for a subnanosecond electron beam pulse duration are determined for the first time. The studies show that radiation of the band with a maximum at about 490 nm the intensity of which decreases toward the short-wave spectral region is recorded in the glow spectra. The glow intensity of this band varies proportionally to the number of electrons in the beam, which allows the possibility of using this radiation for determination of the number of high energy electrons in electron beams. 相似文献
8.
The boundary of the zone in which sputtered atoms are thermalized in the substrate–target drift space during the ion-plasma magnetron deposition of films is determined theoretically and experimentally. A comparison of the thicknesses of films deposited on the front and back sides of substrates situated at different distances from the target makes it possible to divide the flow of atoms sputtered toward substrates into direct and diffusion flows and to determine the dimensions of the spatial zone in which sputtered atoms are thermalized. The experimental data are in quantitative agreement with the results of a statistical simulation of the thermalization process of atomic particles during the ion-plasma deposition. This simulation enables optimization of the technology of defect-free growth of films with uniform thickness on substrates with complex 3D configuration. 相似文献
9.
S. P. Kozyrev I. V. Kucherenko M. Cestelli Guidi R. Triboulet 《Physics of the Solid State》2007,49(12):2307-2311
The paper reports on assignment of lattice reflection spectra of the Hg1?x Znx Te alloys (x = 0.10, 0.35, and 0.55) measured in the 40–300-K temperature interval and on a comparative analysis of the lattice vibration parameters for two alloy systems, HgZnTe and HgCdTe, in the low-frequency optical vibration region (the region of the anomalous Hg-Te vibrational mode in HgTe). While the parameters of the fundamental lattice modes are closely similar, the temperature dependences of the low-frequency modes of the two alloy systems are radically different. Their thermal activation energies for the HgZnTe and HgCdTe alloys are 3.3 and 50.0 meV, respectively. The results of the experiment are treated in terms of the double-well potential model for the Hg atom in the alloy lattice. 相似文献
10.
Magkoev T. T. Grigorkina G. S. Zaalishvili V. B. Burdzieva O. G. Kozyrev E. N. Tuaev G. E. Fukutani K. 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2020,94(2):401-404
Russian Journal of Physical Chemistry A - A set of ultrahigh-vacuum surface analysis techniques are used to make a comparative study of the formation of nanosized gold clusters on the surfaces of... 相似文献