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51.
Monte Carlo simulations are adopted to study the electron transport porcess in the non-uniform electric field.Some important parameters of electrons in diamond films dynamic process at low temperature via EACVD such as angle distribution,energy distribution,average energy of electrons are given.The results indicate that the electron scattering near the substrate is mainly of a large-angle scattering,exhibiting a double-peaking distribution .All of the conclusions provide some theoretical data referential to the vapor dynamic model of diamond film growth at low temperature via EACVD. 相似文献
52.
Fluorinated amorphous carbon films (a-C:F) were prepared at different temperatures using a microwave electron cyclotron resonance chemical vapor deposition (ECR-CVD) reactor with CHF3 and C2H2 as source gases. Films were annealed at 500℃ in vacuum ambience inorder to investigate the relationship of their thermal stability, optical and electrical propertieswith deposition temperature. Results indicate that the films deposited at high temperature have a less CFx bonding and a more cross-linking structure thus a better thermal stability. They also have a lower bandgap, higher dielectric constant and higher leakage current. 相似文献
53.
储松潮 《电力电容器与无功补偿》2003,(1)
电容器用双向拉伸聚丙烯薄膜的打滑现象 ,是影响薄膜电容器制造质量的关键因素之一。本文分析了薄膜打滑机理、薄膜粗化机理 ,并进行了大量工艺试验 ,研究了影响薄膜打滑的主要因素 ,并提出了解决方法。优化合理的加工温度工艺是改进薄膜打滑的关键 相似文献
54.
介绍以纯金属为基体,PVC为载体,α-萘胺为活性物质,三氯甲烷为溶剂研制成的聚合物膜电极,将它用于测定溶液的pH,取得了一些成效。 相似文献
55.
Joe Essid 《Computers and the Humanities》2004,38(3):317-333
A few ideas from film theory, most notably Eisenstein's concept of montage, can improve students' understanding of hypertexts and lessen their resistance to open-ended, nonlinear narratives. These structural characteristics, so frustrating to many new readers of hypertext, can also be found in popular and experimental films. In particular, Godfrey Reggio's (1983) documentary Koyaanisqatsi provides a good starting point for merging hypertext and film theory. Koyaanisqatsi not only broke new ground for documentary film; its structure also resembles Landow's model for an axial hypertext. At the same time, techniques pioneered by Landow, Joyce, Guyer, and others involved in creating and critiquing hypertext can be used to examine film. Having students look closely at Koyaanisqatsi's composition allows them to become amateur cinematographers, who now possess software for breaking a film down and examining its composition, montage, transitions, subliminal messages, and motifs – a process that may then be applied to hypertext. 相似文献
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Many studies have been carried out on two-phase flow heat transfer in channels with hydraulic diameter bigger than 6 mm, but relatively little work has been done for small diameter channels in the meso and compact range (diameter from 0.1 to 3 mm). The use of exchangers with small channels in refrigeration units, which are very numerous besides, could bring a significant reduction of the internal volume of the exchanger, and therefore diminish the refrigerant charge of the whole refrigerating system. One can imagine the interest to widen knowledge on the flow and the heat transfer in small-diameter tubes. This paper examine the thermal behavior of refrigerants boiling in small pipes. The correlations available for in-tube evaporation heat transfer coefficient are discussed and evaluated, when possible, and new research areas of relevance than can contribute to expand the use of small-diameter channels evaporators in refrigeration units are suggested. 相似文献
59.
王学华 《武汉理工大学学报(材料科学英文版)》2004,19(1)
1 IntroductionInrecentyears ,theoreticalandexperimentalinvesti gationsonthetitaniumoxidefilmsareconductedonac countoftheirremarkableproperties .Titaniumdioxidefilmshaveattractedconsiderableattentiontoapplytomi croelectronicdevices ,opticalthin filmdevice… 相似文献
60.
Structural and electrochemical properties of vanadium oxide thin films grown by d.c. and r.f. reactive sputtering at room temperature 总被引:7,自引:0,他引:7
Vanadium oxide thin films were grown at room temperature by direct current and radio-frequency reactive sputtering systems to compare the structural and electrochemical properties. Rutherford backscattering spectrometry and Fourier transform infrared measurements reveal that the composition of the as-deposited films consists of the V2O5 phase regardless of the deposition methods. Wide-angle X-ray diffraction measurements show that the crystallinity of the as-deposited V2O5 films is different depending on the deposition method. Films deposited by direct current reactive sputtering were amorphous, whereas films deposited by radio-frequency reactive sputtering were crystalline. Scanning electron microscopy measurements show that the V2O5 films grown by radio-frequency reactive sputtering had a large grain size but the films grown by direct current reactive sputtering were amorphous. Charge–discharge measurements taken at room temperature with a constant current clearly indicate that the films grown by direct current sputtering demonstrated typical amorphous behavior, whereas the V2O5 films grown by radio-frequency sputtering demonstrated the discharge behavior of crystalline V2O5. The origin of the structural and electrochemical properties of film grown by radio-frequency reactive sputtering is a self-bias effect. The self-bias effect induces ion bombardment during the growth of vanadium oxide thin film. These results suggest that direct current reactive sputtering is more desirable for growing amorphous V2O5 thin film than radio-frequency reactive sputtering. 相似文献