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71.
M. D. Efremov V. A. Volodin L. I. Fedina A. A. Gutakovskii D. V. Marin S. A. Kochubei A. A. Popov Yu. A. Minakov V. N. Ulasyuk 《Technical Physics Letters》2003,29(7):569-571
Polycrystalline silicon films on polyimide substrates were obtained by a method based on the crystallization of amorphous
films under the impact of nanosecond pulses of excimer laser radiation. Characteristics of the film structure were studied
by methods of Raman scattering and high-resolution electron microscopy. For the laser crystallization regimes employed, nanocrystalline
silicon films with an average grain size of 5 nm were obtained. The results are of interest for the development of large-scale
microelectronic devices (active thin-film transistor matrices) on cheap flexible substrates. 相似文献
72.
Phonological competition theory states that competition among discrepant segments of similar words leads to inhibition of high-frequency word-naming responses in form-related priming tasks. If segments are selected sequentially, competition should be greater for begin-related pairs (storage-story), in which discrepant segments are late in the words, than for end-related pairs (glory-story), in which discrepant segments are selected before the shared ones. This pattern was not observed in standard visual priming, probably because of the influence of parallel orthographic input. However, it was observed in a repetitive word-pair production task in which visual input was absent. The findings favor a class of models in which nonsequential activation of phonological content precedes sequential selection of the segments of words to be spoken. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
A.Gabaldon A.Molina C.Roldan J.A.Fuentes E.Gomez F.Marin F.Se Quera P.Morales 本刊编辑部 《供用电》2003,20(6):6-9
0 引言 为了在用能效率上作出工程努力,Cortagena技术大学去年4月已决定实施一项雄心勃勃的计划,要在此后的4年中削减用电费用。为了证实不同政策的可行性和成本效益,应用于原海军医院(工业工程高等技术学校总部)的许多展示活动将在最近期内完成。当然,在此建筑中合理用电的对象将集中在两个主要的电气末端即:电 相似文献
74.
Joris W. Thybaut C.S. Laxmi Narasimhan Guy B. Marin Joeri F.M. Denayer Gino V. Baron Pierre A. Jacobs Johan A. Martens 《Catalysis Letters》2004,94(1-2):81-88
Hydroconversion of octane over platinum loaded acid zeolites was simulated using a single-event microkinetic model. Significantly different values for the alkene standard protonation enthalpies, i.e., ?59.2 and –94 kJ mol?1 for the charging of secondary and tertiary carbon atoms respectively, were obtained. This difference is in favor of a carbocationic nature of the reactive intermediates on the acid sites rather than surface alkoxides. The concentration of alkylcarbenium ions on a Pt/H-USY catalyst resulting from protonation of alkenes in n-octane hydrocracking was calculated. It was strongly dependent on pressure and temperature. At a reaction temperature of 506 K, a total pressure of 0.45 MPa and H2/HC molar ratio of 13.13, the concentration of alkylcarbenium ions corresponds to 15% of the total acid site concentration. At higher total pressures this percentage is lower and can be assumed to be negligible. The presence of a finite alkylcarbenium ion concentration in the zeolite pores results in a reduction of the free space available for physisorption of alkanes. Refined kinetic models are obtained when including this effect. Depending on the nature of the zeolite, alkylcarbenium ion concentrations can be significantly different owing to differences in alkane physisorption and alkene protonation. Literature data were rationalized using the refined kinetic model. 相似文献
75.
76.
K. D. Mynbaev N. L. Bazhenov M. V. Yakushev D. V. Marin V. S. Varavin Yu. G. Sidorov S. A. Dvoretsky 《Technical Physics Letters》2014,40(8):708-711
The impurity-defect structure of heteroepitaxial Cd x Hg1 ? x Te/Si (0.35 < x < 0.39) layers grown by molecular beam epitaxy for the creation of arsenic-ion-implanted p +-n junctions has been studied by the photoluminescence method. It is established that full realization of the possibilities of p +-on-n photodiode structures based on the CdHgTe/Si system is hindered by uncontrolled doping of the material that leads to the formation of both shallow (impurity level energy ~10 meV) and deep (~50 meV) acceptor levels. 相似文献
77.
Kevin P. Musselman Andrew Marin Andreas Wisnet Christina Scheu Judith L. MacManus‐Driscoll Lukas Schmidt‐Mende 《Advanced functional materials》2011,21(3):573-582
A novel buffering method is presented to improve the stability of zinc oxide processed in aqueous solutions. By buffering the aqueous solution with a suitable quantity of sacrificial zinc species, the dissolution of functional zinc oxide structures and the formation of unwanted impurities can be prevented. The method is demonstrated for ZnO films and nanowires processed in aqueous solutions used for the selective etching of mesoporous anodic alumina templates and the electrochemical deposition of Cu2O. In both cases, improved ZnO stability is observed with the buffering method. ZnO‐Cu2O heterojunction solar cells (bilayer and nanowire cells) synthesized using both traditional and buffered deposition methods are characterized by impedance spectroscopy and solar simulation measurements. Buffering the Cu2O deposition solution is found to reduce unwanted recombination at the heterojunction and improve the photovoltaic performance. 相似文献
78.
Heteroepitaxial structures n-Cd x Hg1 ? x Te for the near-infrared spectral range (x ≈ 0.4) are grown by molecular beam epitaxy on Si(310) substrates 72.6 and 100 mm in diameter. High composition homogeneity over the structure area is attained; the variation in x for 100-mm wafers is 0.015–0.025. During growth, the mercury-cadmium telluride (MCT) layers are doped with In with the concentration (0.5–3) × 1015 cm?3. The magnetic-field dependences of the Hall effect are studied in the range of magnetic fields 0.05–1.0 T at liquid-nitrogen and room temperatures. The experimental values of the electron mobility at room temperature are close to the calculated ones, while at liquid-nitrogen temperature, they are lower than the calculated mobilities. The possible causes of this phenomenon such as the influence of the MCT transition layer at the interface with the CdTe buffer layer and lattice defects of MCT are discussed. The variation in the concentration and mobility of charge carriers in MCT structures after activation annealing are studied. 相似文献
79.
The authors present a stochastic model of electric capacity expansion planning under uncertainty in demand. The goal of this problem is to determine the most interesting investments (plants and capacity levels) over the considered planning time (up to several years). Periods are divided into smaller subperiods (e.g. weekly or monthly) for which demand is assumed uncertain and modeled as a continuous probability distribution function. This leads to consider the risk associated to each decision for the capacity to be used (electricity generation). A first approach as a nonlinear continuous model is presented. Benders decomposition and Lagrangean relaxation-decomposition are proposed as solution methods, where the structures of the related sub-problems are exploited to speed up the convergence. The authors provide a large computational experience and comparisons within these methods and other general purpose optimization packages, and focus the report on the advantages of each 相似文献