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排序方式: 共有844条查询结果,搜索用时 31 毫秒
31.
N. V. Mamedov N. N. Shchitov D. V. Kolodko I. A. Sorokin D. N. Sinel’nikov 《Technical Physics》2018,63(8):1129-1136
The results of investigation of discharge characteristics of the Penning plasma source are presented. Volt-ampere characteristics (VAC), energy distribution, and mass-charge composition of ions emitted from the discharge under different modes of its combustion were measured. The connection between the discharge current bursts and increase in the potential drop (up to 50% of the anode voltage) is established. The measured VACs agree well with the theoretical dependencies. It is shown that the content of atomic hydrogen ions increases from 5 to 10% with an increase in the anode voltage from 1 to 3.5 kV and the power applied in the discharge (from 0.2 to 3 W). 相似文献
32.
Lomaev M. I. Nechaev B. A. Padalko V. N. Kuznetsov S. I. Sorokin D. A. Tarasenko V. F. Yalovets A. P. 《Technical Physics》2012,57(1):124-130
Neutron emission during a nanosecond deuterium discharge formed at the nonuniform electric field is investigated. A stable
neutron yield is observed when the cathode is made of metallic plates covered by a layer of deuterated zirconium and the anode
is made of stainless steel in the form of a tube. It is shown that, when the deuterium pressure equals several Torr, neutrons
are emitted from both deuterated and deuterium-free cathodes. The influence of the anode design on the neutron yield is studied. 相似文献
33.
Electronic band structure and energetic stability of two types of 〈110〉 and 〈001〉 oriented silicon nanowires in β-Sn phase
with the surface terminated by hydrogen atoms were studied using density functional theory. It was found that β-Sn nanowires
are metastable with zero band gap against to nanowires in diamond phase. The relative energy of the studied wires tends to
the energy of the bulk silicon crystal in β-Sn phase. 相似文献
34.
Guralchuk GY Sorokin AV Katrunov IK Yefimova SL Lebedenko AN Malyukin YV Yarmoluk SM 《Journal of fluorescence》2007,17(4):370-376
Optical spectroscopy experiments were used to study the features of cyanine dye 3,3′-dimethyl-9-(2-thienyl)-thiacarbocyanine
iodide (L-21) aggregation in binary solutions DMF:Tris–HCl buffer (pH = 8) containing nucleic acids (DNA or RNA). The appearance
of absorption and luminescence bands associated with J-aggregates and dimers that are formed within the minor groove of DNA
has been observed. The model of L-21 J-aggregate structure is proposed. It has been found that dimers are the building blocks
of L-21 J-aggregates. Disorientation in dimers caused by the minor groove curvature is reason of observation of Davydov splitting
in absorption spectrum of L-21 J-aggregates. In the solution containing DNA the absorption and luminescence bands of L-21
J-aggregates exhibit the specific properties that allows the dye L-21 to be used as a fluorescent probe for DNA detection. 相似文献
35.
N. N. Andrianova A. M. Borisov Yu. S. Virgiliev E. S. Mashkova A. S. Nemov E. A. Pitirimova A. I. Sorokin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2007,1(2):121-126
The temperature dependences (?200°C < T ≤ 350°C) of the ion-induced electron emission yield γ and the structures of modified surface layers have been studied experimentally for SU-850, SU-1000, SU-1300, SU-2000, and SU-2500 glassy carbons under high-dose 30-keV Ar+ and N 2 + ion irradiation. Glassy carbons manufactured using a relatively high heat-treatment temperature T ht exhibit a stepwise increase in the electron yield at certain annealing temperatures T a. The same behavior is observed for graphitized carbon materials. For low-temperature glassy carbons, the electron yield exhibits a monotonic increase with increasing irradiation temperature. The observed differences are related to the occurrence of different structural types of fullerene-like nanoparticles in the low-and high-temperature glassy carbons. 相似文献
36.
Sorokin N. I. Buchinskaya I. I. Ivanovskaya N. A. Orekhov A. S. 《Crystallography Reports》2022,67(2):272-277
Crystallography Reports - Ceramic samples of the Pb0.67Cd0.33F2 composition have been obtained using grinding and mechanical synthesis with subsequent cold pressing. The ceramic density was 84... 相似文献
37.
Sorokin N. I. Gaynutdinov R. V. Voronov V. V. Chernova E. V. Fedorov P. P. 《Crystallography Reports》2021,66(1):126-129
Crystallography Reports - The electrical conductivity of natural samples of exogenous silicides has been studied. In the temperature range of 515?700 K, the conductivity increases from 1.1... 相似文献
38.
Crystallography Reports - The compositions of nonstoichiometric phases Pb1 – xRxF2 + x (CaF2 type, R is a rare-earth element) have been optimized with... 相似文献
39.
Sulyanova E. A. Bolotina N. B. Kalukanov A. I. Sorokin N. I. Karimov D. N. Verin I. A. Sobolev B. P. 《Crystallography Reports》2019,64(1):41-50
Crystallography Reports - The defect structure of as-grown SrF2 and nonstoichiometric phases Sr1 – xLaxF2 + x (x = 0.11, 0.20, 0.32, 0.37, 0.47) single... 相似文献