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21.
Tetsuya Ikuta Yuki Miyanami Hayato Iwamoto Takayoshi Shimura Kiyoshi Yasutake 《Science and Technology of Advanced Materials》2007,8(3):142-145
Selective epitaxial Si with a high arsenic concentration of 2.2×1019 atoms/cm3 was deposited at a high growth rate of 3.3 nm/min under atmospheric pressure. It was confirmed that this method had excellent selectivity and produced films having good crystalline quality, abrupt dopant profiles at the interfaces, and smooth surfaces. The growth mechanism is discussed in terms of the relationship between the effects of arsenic surface segregation and etching by hydrogen chloride. 相似文献
22.
Colour extension properties of individual pigments and effects on shades of foundations in cake form
AKIRA TSUGITA TAKASHI FUKISHIMA TOHRU YONEYA YASUSH INISHIJIMA 《International journal of cosmetic science》1985,7(1):15-27
The mechanism of colour change during the pigment dispersion process and during powder application to the skin surface was studied by examining the colour extension properties of Yellow. Red , and Black iron oxides in white powder bases. A new measure for the evaluation of the degree of colour extension was devised. This measure corresponded well with human visual sensation, and was found to be useful for comparing the rates of colour extension of pigments. The rate of colour extension of pigments was found to vary in the order: Yellow acicular Red granular Red Black. This result explains colour darkening and the change towards reddish tones during the pigment dispersion process, because Yellow extends fully in the early stage of the process but Red , especially in granular form, and Black continue to extend even in the later stage. Acicular Red iron oxide is more favourably employed than the granular form to attain sufficient colour extension of foundations with lower energy expenditure, and to decrease the discrepancy between the cake colour and the colour of applied powder.
Le développement des oxydes de fer et effet sur les nuances des fonds de teint compacts 相似文献
Le développement des oxydes de fer et effet sur les nuances des fonds de teint compacts 相似文献
23.
Martin Sulzmann Kenny Zhuo Ming Lu 《Electronic Notes in Theoretical Computer Science》2006,148(2):239
We consider the problem of integrating XDuce into ML. This is difficult because of incompatible type and value representations. Our solution is a type-driven translation scheme from XDuce to ML based on a structured representation of XDuce values. XDuce type inference guides the insertion of appropriate coercion functions to translate regular expression pattern matching and uses of semantic subtyping. We can extend our translation scheme to include ML function calls and patterns into XDuce. Thus, we can embed XDuce into ML. Our results allow to enrich the ML language with support for dealing with semi-structured data. 相似文献
24.
Hong ZHU 《Frontiers of Computer Science in China》2012,6(1):40-56
Meta-modelling plays an important role in model driven software development.In this paper,a graphic extension of BNF (GEBNF) is proposed to define the abstract syntax of graphic modelling languages.Fro... 相似文献
25.
Two experiments, with 80 undergraduates, replicated and extended research by R. T. Croyle and J. Cooper (see record 1984-11595-001) indicating that cognitive dissonance involves physiological arousal. In Exp I, Ss wrote counterattitudinal essays under conditions of high or low choice and, to assess arousal effects owing to effort, with or without a list of arguments provided by the experimenter. In high-choice conditions only and regardless of effort, Ss showed both arousal (heightened galvanic skin response) and attitude change. Arousal, however, did not decline following attitude change. The more effortful task (no arguments provided) produced increased arousal but not greater attitude change. In Exp II, the opportunity to change one's attitude following a freely chosen counterattitudinal essay was manipulated. As in Exp I, arousal increased following the essay but did not decline following a postessay attitude change opportunity. When Ss were not given an attitude change opportunity, however, arousal did decline. It is suggested that if dissonance is a drive state, drive reduction typically may be accomplished through gradual cognitive change or forgetting. (47 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
浅析科技英语中词义的汉译 总被引:1,自引:0,他引:1
通过实例阐述了在进行科技英语的汉译时,只有根据原文的专业、行业、技术内容、词的本义和可能的引伸义,结合词的上下文语境,才能准确、恰当地确定英语词义的汉译。文章指出明白通畅、浅显易懂、准确的词义是科技英语汉译成功的基础。 相似文献
27.
管无芯弯曲中塑性变形规律的研究 总被引:7,自引:1,他引:7
通过大量管材弯曲试验,分析了沿弯曲线的切向和管壁厚方向的应力应变状态,给出弯管内、外侧管壁厚变化量和切向应变的近似计算公式。在后续试验的基础上,逐步将修正公式适用于实际生产。同时,为管材弯曲成形机理研究作了相应的基础准备工作。 相似文献
28.
针对配电网发生单相接地故障且分布式电源(distributed generations, DGs)大量接入后,配电网结构和运行方式复杂多变、故障后电气量不明显、故障特征弱等特点,提出一种基于改进局部均值分解(improved local mean decomposition, ILMD)和能量相对熵的主动配电网故障定位方法。首先,利用镜像延拓将信号在两端延拓,消除LMD存在的端点效应,同时,在信号中加入自适应噪声,克服LMD存在的模态混叠问题,对各区段暂态零序电流进行ILMD分解;然后对分解后所有乘积函数(product function, PF)的能量相对熵进行计算,所有PF分量的相对能量熵之和即为区段间的相对能量熵,通过所设置的定位判据,对故障区段进行判断。仿真结果表明,所提算法在10 kV小电流接地系统和改进的IEEE33节点系统中,在不同的仿真条件下故障定位结果准确率高,验证了所提方法的准确性。 相似文献
29.
30.
Thermal radical copolymerization of styrene (S) and maleimide (MI) at 125°C in diglyme in the presence of 2,2,6,6‐tetramethylpiperidin‐1‐yloxyl radical (TEMPO) was studied. Mole fractions of maleimide in the feed, FMI, varied in the range 0.1–0.9. A quasiliving reaction process proceeded yielding copolymers with a low polydispersity (Mw/Mn = 1.17–1.41). The found azeotropic composition, (FMI)A = 0.46, did not differ substantially from that (0.5) in the conventional radical S‐MI copolymerization. At a higher conversion or MI content in the feed, deactivation of the copolymer chains occurred. The obtained TEMPO‐terminated S‐MI copolymers readily initiated polymerization of styrene; chain extension of the macroinitiators took place, giving poly(S‐co‐MI)‐block‐poly(S) diblock copolymers. The synthesized copolymers containing S and MI units were characterized by elemental analysis, NMR spectroscopy, size‐exclusion chromatography, and differential scanning calorimetry. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 1863–1868, 2004 相似文献