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21.
Viktor Sverdlov Tibor Grasser Hans Kosina Siegfried Selberherr 《Journal of Computational Electronics》2006,5(4):487-450
Transport in single and double barrier devices is studied using a Monte Carlo solver for the Wigner transport equation. This
approach allows the effects of tunneling and scattering to be included. Several numerical methods have been improved to render
the Wigner Monte Carlo technique more robust, including a newly developed particle annihilation algorithm. A self-consistent
iteration scheme with the Poisson equation was introduced. The role of scattering and space charge effects on the electrical
characteristics of n-i-n nanostructures, ultra-scaled double gate MOSFETs, and GaAs resonant tunneling diodes is demonstrated.
An erratum to this article can be found at 相似文献
22.
I. G. Rodionova E. T. Shapovalov M. E. Kovalevskaya O. N. Baklanova D. A. Burko N. I. Endel' Yu. B. Gusev R. E. Gliner A. M. Lamukhin V. V. Kuznetsov V. L. Chernousov S. D. Zinchenko S. V. Efimov M. V. Shurygina A. D. Gorin 《Metallurgist》2005,49(7-8):314-323
A method involving alternating immersion in a 3.5% NaCl solution has been developed for corrosion tests of automobile sheet.
Results obtained from 30 cycles of tests (10 + 50 min) of specimens of steels 08Yu, 08ps, 08YuP, 08YuDP, 08GSYuT, and IF established
the dependence of the steel's unit weight gain from corrosion products on its combined content of carbon and silicon: steels
with a lower content of these elements show a smaller gain in weight, i.e., they exhibit greater corrosion resistance. Steel
alloyed with copper (0.23–0.34%) and phosphorus (0.06–0.08%) – the production of which has been mastered by the company Severstal'
— has the highest resistance to corrosion. Use of the method makes it possible to rank grades of automobile sheet in one of
three corrosion-resistance classifications in relation to their chemical composition and the parameters of the production
process.
__________
Translated from Metallurg, No. 8, pp. 46–52, August, 2005. 相似文献
23.
Yurii G. Tkachenko Viktor F. Britun Emmanuil V. Prilutskii Dzhemma Z. Yurchenko Galina A. Bovkun 《Powder Metallurgy and Metal Ceramics》2005,44(3-4):196-201
We have investigated how the composition, grain morphology, and method of preparing the starting mixture affect the processes that form the structure and phase composition of B4C - SiC composites during hot pressing. We found that, depending on the composition of the initial powder mixtures, which is responsible for different mechanisms of consolidation of ceramic materials during hot pressing, the grain size of the main B4C phase and its defect content as well as the nature of the SiC phase distribution within the material differ significantly. When B4C - SiC composites with a low SiC content are made from initial B4C - B4Si - B - C powder mixtures those composites have a high cracking resistance because of their fine grain structure.__________Translated from Poroshkovaya Metallurgiya, Nos. 3–4(442), pp. 112–119, March–April, 2005. 相似文献
24.
Polonium presents no danger under normal operating conditions when the coolant loop is sealed. In our country, we have almost 40 years of experience in working with radioactive lead–bismuth coolant in the reactors used in nuclear-powered submarines and ground-based testing prototypes. This experience has made it possible to study how the polonium radiation conditions inside working enclosures are produced and to develop effective safety measures for different operating regimes, including irregular situations and accidents.Data are presented on the polonium radiation conditions in certain typical operating and accident situations in a nuclear submarine: spillage of a substantial amount of coolant directly into the reactor bay, the consequences of an interloop leak in a steam generator, and refueling with fresh nuclear fuel.Regular medical-biological examinations of the workers participating in the operation of the system, repair work, and liquidation of the consequences of accidents did not show any cases of irradiation by polonium above the established health norms.Inferences are drawn from studies performed in this and other countries of polonium emission from lead-based polonium-containing media when such media are heated in vacuum and in an inert-gas atmosphere in the temperature range 300–800°C. 相似文献
25.
Bizyulev A. N. Muzhitskii V. F. Zagidulin R. V. Efimov A. G. Sysoev A. M. 《Russian Journal of Nondestructive Testing》2004,40(5):350-355
The field of application, the features of operation, and the main performance characteristics of a -12 eddy-current flaw detector are considered. Methods of digital data processing for improving the recognition of flaw-produced signals against the background noise are presented. 相似文献
26.
A simple method is proposed for determining the critical pressure that does not destroy Cd x Hg1?x Te diodes in hybrid assembling. The method allows obtaining a set of data that reliably define the critical parameter (the value of force) of the flip-chip hybrid FPA process. The method was tested on Cd x Hg1?x Te samples (x = 0.21). It is found that the abrupt change in the electrophysical properties of the material occurs when the diameter of indium bumps increases 2 times and more during compression at a pressure of about 3 kg/mm2. The obtained gage load/bump deformation dependences show that this pressure corresponds to the beginning of the region of indium strengthening on the deformation curve. 相似文献
27.
Márk Juhász Viktor L. Nagy Hajnal Székely Dorottya Kocsis Zsolt Tulassay János F. László 《Journal of the Royal Society Interface》2014,11(98)
This pilot study was devoted to the effect of static magnetic field (SMF)-exposure on erosive gastritis. The randomized, self- and placebo-controlled, double-blind, pilot study included 16 patients of the 2nd Department of Internal Medicine, Semmelweis University diagnosed with erosive gastritis. The instrumental analysis followed a qualitative (pre-intervention) assessment of the symptoms by the patient: lower heartburn (in the ventricle), upper heartburn (in the oesophagus), epigastric pain, regurgitation, bloating and dry cough. Medical diagnosis included a double-line upper panendoscopy followed by 30 min local inhomogeneous SMF-exposure intervention at the lower sternal region over the stomach with peak-to-peak magnetic induction of 3 mT and 30 mT m−1 gradient at the target site. A qualitative (post-intervention) assessment of the same symptoms closed the examination. Sham- or SMF-exposure was used in a double-blind manner. The authors succeeded in justifying the clinically and statistically significant beneficial effect of the SMF- over sham-exposure on the symptoms of erosive gastritis, the average effect of inhibition was 56% by p = 0.001, n = 42 + 96. This pilot study was aimed to encourage gastroenterologists to test local, inhomogeneous SMF-exposure on erosive gastritis patients, so this intervention may become an evidence-based alternative or complementary method in the clinical use especially in cases when conventional therapy options are contraindicated. 相似文献
28.
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30.
Didem Ag Seleci Viktor Maurer Firat Baris Barlas Julian Cedric Porsiel Bilal Temel Elcin Ceylan Suna Timur Frank Stahl Thomas Scheper Georg Garnweitner 《International journal of molecular sciences》2021,22(9)
The development of multifunctional nanoscale systems that can mediate efficient tumor targeting, together with high cellular internalization, is crucial for the diagnosis of glioma. The combination of imaging agents into one platform provides dual imaging and allows further surface modification with targeting ligands for specific glioma detection. Herein, transferrin (Tf)-decorated niosomes with integrated magnetic iron oxide nanoparticles (MIONs) and quantum dots (QDs) were formulated (PEGNIO/QDs/MIONs/Tf) for efficient imaging of glioma, supported by magnetic and active targeting. Transmission electron microscopy confirmed the complete co-encapsulation of MIONs and QDs in the niosomes. Flow cytometry analysis demonstrated enhanced cellular uptake of the niosomal formulation by glioma cells. In vitro imaging studies showed that PEGNIO/QDs/MIONs/Tf produces an obvious negative-contrast enhancement effect on glioma cells by magnetic resonance imaging (MRI) and also improved fluorescence intensity under fluorescence microscopy. This novel platform represents the first niosome-based system which combines magnetic nanoparticles and QDs, and has application potential in dual-targeted imaging of glioma. 相似文献