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191.
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
192.
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
193.
器官供需严重不平衡导致了人体器官买卖的产生,器官买卖对供体和受体均存在潜在风险,对社会危险性也不容忽视.分析了器官买卖链条中供体、受体和中介各自的角色和地位,并提出了立法推动尸体器官捐献、加强医院和医务人员承担的法律责任、打击买卖中介和加强网络监管等建议. 相似文献
194.
对于女性盆腔脏器脱垂的手术治疗,传统的手术方式包括阴道封闭术、曼氏手术和阴式全子宫切除术.阴道封闭术操作相对简单,适用于无性生活要求的、合并症较多的年老体弱者,但术后可能存在新发压力性尿失禁,并且导致性功能障碍,术中是否切除子宫尚有争议.曼氏手术保留子宫、操作简单,但术后脱垂复发及妊娠后宫颈机能不全问题仍有待研究.阴式全子宫切除术对于POP-Q评分II期及以内的脱垂患者,治疗效果最佳,期别高的患者术后复发仍可使用保守或再次手术治疗补救,本手术方式术后较少出现性交痛.总而言之,选择适当的适应证并积极与患者沟通后,女性盆腔脏器脱垂的传统手术治疗仍为不错的治疗方式. 相似文献
195.
196.
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
197.
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
198.
The purpose of this study was to investigate the differences of knee concentric and eccentric strength and impact related knee biomechanics between jumpers and non-jumpers during step-off landing tasks. Ten male college swimming athletes (non-jumpers) and 10 track and volleyball athletes (jumpers) were recruited to participate in two test sessions: a muscle strength testing session of concentric and eccentric extension for dominant knee joint at 60 °/s and 180 °/s and a landing testing session. The participants performed five trials of step-off landing in each of four conditions: soft and stiff landing from 0.4 m and 0.6 m landing heights. The three-dimensional kinematics and ground reaction force were recorded simultaneously during step-off landing conditions. The results showed that the jumpers had significantly greater peak knee eccentric extension and concentric flexion torques compared to the non-jumpers. No significant group effects were found for peak vertical ground reaction force and knee range of motion during landing. The jumpers had significantly greater knee contact flexion angle, maximum knee flexion angle and initial knee extension moment compared to the non-jumpers. These results suggest that these athletes adopted a favorable impact attenuation strategy that is related to the greater knee eccentric muscle strength and training. 相似文献
199.
The current study aimed to analyze the importance of trait emotional intelligence in life satisfaction and to extend the previous literature by investigating the potential mediating effects of resilience and affect balance in this relationship. To test the study hypotheses, self-report measures of trait emotional intelligence, resilience, positive and negative affect, and life satisfaction were administrated to 263 undergraduates. Correlation analysis indicated that trait emotional intelligence was positively correlated with life satisfaction. Mediational analyses showed that trait emotional intelligence exerted its indirect effect on life satisfaction through the simple mediating effect of affect balance and the three-path mediating effect of resilience–affect balance. In addition, resilience played as a partial mediator between trait emotional intelligence and affect balance. Furthermore, multi-group analyses showed that the mediational model was not moderated by gender. Therefore, this study makes a contribution to the complex nature of the association between trait emotional intelligence and subjective well-being. 相似文献
200.
Luke Clark Rui Liu Rebecca McKavanagh Alice Garrett Barnaby D. Dunn Michael R. F. Aitken 《决策行为杂志》2013,26(5):442-450
Gambling near‐misses are non‐rewarded events that resemble a winning configuration. Past research using slot machines has shown that moderate rates of near‐misses increase gambling persistence, but the mechanisms supporting this persistence are unclear. One hypothesis is that near‐misses are mistakenly interpreted as signals of skill acquisition, supporting learning and fuelling the ‘illusion of control’. A slot machine simulation was administered to 60 volunteers, with ratings of the perceived chances of winning, pleasure and motivation to play following particular outcomes. Psychophysiological measures (electrodermal activity and heart rate) were taken, and gambling persistence was measured after 30 trials. Near‐misses were similar to full‐miss outcomes in that they were regarded as unpleasant. However, near‐misses were akin to win outcomes in that they increased motivations to play and electrodermal activity. Learning was evidenced by the expectancy of winning increasing following wins and decreasing after losses. Although there was no overall change in expectancy of winning after near‐misses across all participants, those subjects reporting a greater increase in the expectancy of winning following a near‐miss showed more persistent play, consistent with the learning hypothesis. Greater heart rate acceleration following near‐misses was also associated with persistence. We also observed differential effects of near‐misses where the reel stopped either side of the winning position (‘payline’): motivational effects were restricted to near‐misses stopping before the payline, whereas near‐misses that stopped after the payline were primarily aversive. The payline effects are not predicted by the learning hypothesis and may indicate an affective component to near‐misses, possibly linked to counterfactual processing. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献