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101.
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   
102.
103.
The phenomenology of autobiographical memories varies on a number of dimensions: some memories are vivid and others dim; some are emotionally intense and others lack emotional content. The present research sought to develop a psychometrically-sound scale to assess the entire range of dimensions on which autobiographical memories differ. We reviewed the literature on memory experiences and identified 10 relevant dimensions: Vividness, Coherence, Accessibility, Time Perspective, Sensory Details, Visual Perspective, Emotional Intensity, Sharing, Distancing, and Valence. We constructed a comprehensive item pool to assess these dimensions and, using data from several large samples (Ns=941; 510; 212), we showed that: (a) all 10 scales had adequate reliability (median alpha=.87; range=.72 to .97), (b) the 10-factor structure provided a good fit to the data, and (c) gender, personality, and memory recency had theoretically meaningful relations with the 10 scales. For example, gender and ethnicity differences in phenomenology were mediated by memory content, and early and recent memories had distinct phenomenologies. The discussion focuses on the theoretical and practical utility of the 10 scales.  相似文献   
104.
分子靶向治疗是这几年来消化道肿瘤治疗领域的热门话题.这类新一代的分子靶向生物治疗模式,将在临床治疗肿瘤实践中具有广阔的应用前景.从事肿瘤研究的临床医务人员需要综合归纳这些信息,融汇入自己的认知将之合理应用于患者.我们将真正进入传统的细胞毒性药物攻击与非细胞毒性靶向性药物相结合使用的时代,真正实现延长患者的生命,改善其生活质量的目标.  相似文献   
105.
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   
106.
为探究主动发展倾向和社会支持对新生市民城市生活适应性的作用机制,本研究构建了结构方程模型.采用两个自编量表和一个现成量表,运用两阶段抽样调查法,在作为统筹城乡发展试验区的重庆市范围内,对已经取得城镇户口的新生市民进行问卷调查,获得有效样本322人.对采集的数据运用统计分析软件SPSS17.0和AMOS18.0进行数据分析和模型检验.结果表明,城市化新生市民的主动发展倾向和社会支持均对新生市民的城市生活适应具有显著影响,其中,社会支持在主动发展倾向对城市生活适应影响中具有部分中介作用.  相似文献   
107.
108.
Since the 1990s researchers have considered as the dominant view on family obligation a set of responsibilities, duties, and obligation of care and assistance, that adult children should assume when parents are old or infirm. This concept is limited, because it assumes that family obligation is salient only in one period of life: when parents reach old age and are infirm. In contrast, a relational approach to family obligation considers family relationships as central to understanding children's duties and responsibilities. Following Stein, family obligation can be defined as felt obligation: expectations for appropriate and negotiated behaviour, perceived within the context of specific personal relationships with kin across life course. Felt obligation is conceptualized in five dimensions: a duty to maintain contact, assistance, avoidance of conflict, personal sharing, and self‐sufficiency. The purpose of the present study was to analyze perceptions of felt obligation in intergenerational relationships (parent–child and family of origin) in different phases of the family life cycle in a specific cultural context (Italy). The sample was composed of 92 parents with children of different ages (infants, school‐aged children, and young adults). The measure addressed the five dimensions of felt obligation, all assessed in various phases of family life. Results indicated differences in dimensions of felt obligation between intergenerational relationships (both parent–child and with family of origin). Some of these differences, such as self‐sufficiency and personal sharing, assumed more importance and salience in some periods of the life cycle than in others.  相似文献   
109.
The aim of the present studies was to investigate whether age‐related improvement found in naturalistic but experimenter‐given prospective memory (PM) tasks can be generalized to real‐life intentions. In Study 1, younger, middle‐aged, and older adults generated a list of intended activities for the following week; one week later they marked the tasks that they had performed. The participants were also asked to rate the importance of each listed intention and to describe the circumstances of completion that were already known to them. We found that, compared with younger adults, older adults attributed a higher degree of importance to their intentions and had the circumstances of their completion better planned. However, the age‐related benefit in the PM performance for all listed intentions was not present for the very important and well‐planned tasks. In Study 2 we manipulated whether younger adults engaged or not in the detailed planning of when their intentions could be completed. It was demonstrated that younger adults who had to perform detailed planning completed their intended activities more often than those who did not plan for their intentions. The results support explanations of the age‐related benefit in everyday PM that highlight the role of importance and planning.  相似文献   
110.
The authors examined age differences in perceived coping resources and satisfaction with life across 3 older-adult age groups (45-64, 65-74, and 75 years and older). The 98 participants represented healthy, socially active, community-residing adults. Group comparisons were made on 12 individual coping scales, and an overall coping resource effectiveness score was computed. No significant differences were found for 11 of the coping resources or for overall coping resource effectiveness. Similar consistencies in life satisfaction were found across the 3 age groups. The findings indicate that (a) for healthy adults, the oldest old cope at least as effectively as their younger counterparts, despite their likelihood of encountering increased levels of stress; and (b) psychologically, old age may be viewed as a time of resilience and fortitude.  相似文献   
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