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261.
Y. Z. Liu X. T. Zu J. Lian L. Wang X. Q. Huang Z. G. Wang 《Philosophical Magazine Letters》2013,93(11):705-712
Ti–Al–Zr alloy has been oxidized at 360°C in alkaline steam at a pressure of 10.3?±?0.7?MPa. Cross-sectional transmission electron microscopy (TEM) observations indicated that the oxide scale of Ti–Al–Zr alloy was composed of outer and inner subscales, in which the outer layer consists of anatase-TiO2 and the inner layer a mixture of TiO and Ti2O. The thickness of the Ti2O, TiO and anatase-TiO2 were approximately 50, 100 and 400?nm, respectively. These results were confirmed by X-ray energy dispersive spectrometry (EDS) measurements. The enhanced corrosion of titanium alloys in LiOH solution is attributed to a high hexagonal Ti2O to tetragonal TiO2 phase transformation rate induced by the substitution of Li+ for Ti4+ in the oxide layer. 相似文献
262.
Yan Chong Zhengdong Liu Andy Godfrey Wei Liu Yuqing Weng 《Philosophical Magazine Letters》2013,93(12):688-696
Cellular precipitation (also known as discontinuous precipitation) has been observed at the grain boundaries of a newly developed nickel-based Inconel740H alloy designed for use at 700?°C in advanced ultrasupercritical coal-fired power plants. By means of element mapping and selected area diffraction, the cellular precipitates were identified as Cr-rich M23C6 carbides. The onset of cellular precipitation was found to follow a pucker mechanism in Inconel740H. The cellular precipitates at the grain boundaries, even at low volume fractions, were severely detrimental to the creep strength at 750?°C. The creep rupture life of Inconel740H containing cellular precipitates at grain boundaries was only one-tenth of that for the alloy without cellular precipitates. The reason for the drastically decreased creep rupture life is attributed to the poor resistance of cellular precipitates to crack propagation during creep. 相似文献
263.
人是一种承担着有死性的存在物,一切从人出发并为了人的事业都必须在"人固有一死"的背景中进行。首先阐述了死亡对于医学的背景意义:死亡是人类面临的客观的、必要的限制,关于死亡的立场对于医学具有源始性与优先性,最后从三个方面揭示了当代医学对于死亡的立场:遗忘。 相似文献
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该研究以广州市与台中市大学生为被试,抽取500人为预测样本及800人为正式施测样本,通过探索性因素分析和验证性因素分析编制生命意义量表,并通过t检验和潜在剖面分析考察两岸大学生生命意义现况的差异.结果表明:(1)编制的生命意义量表由存在意义、追寻意义、存在盈实、苦难接纳、死亡接纳以及求意义的意志等6个维度组成,具有良好的信度和效度.(2)两岸大学生生命意义总体无显著差异;存在盈实、苦难接受与死亡接纳维度有显著或非常显著的差异.(3)潜在剖面分析结果显示,两岸大学生生命意义类型相似.Wald检验结果表明,对于“死亡接纳”维度,台湾与大陆学生在各潜在类别的均分上存在显著的差异. 相似文献
267.
The purpose of this study was to develop a “Scale for Evaluating Creative Culinary Products” based on the nature of these products. We adopted the Consensual Assessment Technique (CAT) to establish the credibility of the scale. The scale comprises 8 categories: professional technique; aroma, taste, and texture; color; modeling and arrangement; garnish; dishware; handling of ingredients; and overall assessment. There are 34 assessment criteria for these 8 categories. Nine culinary experts were invited to evaluate, by means of these criteria, the products of 28 college students studying Chinese cuisine. The degree of interjudge reliability was .98, and the correlation between each criterion and the total scale was between .578 and .856. Through confirmatory factor analysis, the scale was demonstrated to possess a high degree of validity. 相似文献
268.
Visual attention can be deployed to stimuli based on our willful, top-down goal (endogenous attention) or on their intrinsic saliency against the background (exogenous attention). Flexibility is thought to be a hallmark of endogenous attention, whereas decades of research show that exogenous attention is attracted to the retinotopic locations of the salient stimuli. However, to the extent that salient stimuli in the natural environment usually form specific spatial relations with the surrounding context and are dynamic, exogenous attention, to be adaptive, should embrace these structural regularities. Here we test a non-retinotopic, object-centered mechanism in exogenous attention, in which exogenous attention is dynamically attracted to a relative, object-centered location. Using a moving frame configuration, we presented two frames in succession, forming either apparent translational motion or in mirror reflection, with a completely uninformative, transient cue presented at one of the item locations in the first frame. Despite that the cue is presented in a spatially separate frame, in both translation and mirror reflection, behavioralperformance in visual search is enhanced when the target in the second frame appears at the same relative location as the cue location than at other locations. These results provide unambiguous evidence for non-retinotopic exogenous attention and further reveal an object-centered mechanism supporting flexible exogenous attention. Moreover, attentional generalization across mirror reflection may constitute an attentional correlate of perceptual generalization across lateral mirror images, supporting an adaptive, functional account of mirror images confusion. 相似文献
269.
This cross‐sectional study investigated the significant differences in students’ self‐efficacy and their involvement in learning science. Nine hundred and twenty‐two elementary school fifth graders, 499 junior high school eighth graders, and 1455 senior or vocational high school eleventh graders completed the students’ questionnaire. Analyses of variance (ANOVAs) and independent t‐tests compared the significant similarities and differences across school levels and genders. The initial findings were as follows: A sharp decline in boys’ and girls’ self‐efficacy scores from elementary to secondary school levels; boys have significantly higher self‐efficacy scores than girls at vocational and senior high school levels; students with more involvement in science learning presented significantly higher self‐efficacy scores than those with less involvement. The significant discrepancies in terms of gender and age in students’ self‐efficacy and involvement in learning science need to be addressed. Implications and limitations are provided. 相似文献
270.
Yih-Lan Liu 《The Journal of genetic psychology》2013,174(5):557-581
A 2-year longitudinal study was conducted to test 3 causal models about adolescent autonomy, filial piety, beliefs about parental authority, and obedience in terms of personal, prudential, and multifaceted issues. Four hundred and thirty-six students from 10 junior and senior high schools in Taiwan (boys, n = 223; senior high school, n = 211) participated in the study. Hypothesis 1 predicted that autonomy (individuating autonomy vs. relating autonomy) would positively correlate with beliefs about authority legitimacy and obligation to obey, but was not supported. Hypothesis 2 predicted that filial piety (authoritarian piety vs. reciprocal piety) would positively associate with authority beliefs, and was partially supported. Authoritarian piety showed the positive relation with authority beliefs. Hypothesis 3 predicted that beliefs about authority legitimacy and obligation to obey would positively associate with obedience, and was supported. Hypothesis 4 predicted that age might moderate the structure models across domains, but the results indicated that age did not moderate the structural model in the prudential and multifaceted domains. The overall findings of this study reveal that adolescent beliefs about authority serve as a mediator between authoritarian piety and obedience, suggesting that traditional piety still has an influence on parent–child interaction in today's society. 相似文献