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241.
The average velocities of screw dislocations in Ni 3 Al single crystals have been directly measured as a function of resolved shear stress (RSS) and orientation in the temperature domain of the flow stress anomaly using the etch-pit technique. The velocity was found to be extremely sensitive to the RSS in all cases. In contrast with ordinary metals, the screw dislocation velocities in Ni 3 Al show anomalous behaviour; under a constant RSS, the velocities decrease dramatically with increasing temperature. Furthermore, the velocities and the tension-compression asymmetry of the velocities depend on the orientation of applied stress. 相似文献
242.
The aggregation behavior of Au atoms and atomic islands on silicone oil surfaces has been systematically investigated by analyzing the evolution of surface coverage. The apparent Au surface coverage increases linearly with the nominal film thickness at low thicknesses and the rate of increase is almost independent of deposition flux. However, as the deposition flux increases, the surface coverage goes up linearly. Further analysis reveals that the deposition flux strongly affects the system free-energy of the island-oil system and therefore the aggregation behavior of the Au atoms and islands. 相似文献
243.
In this letter, the dislocation patterns on the common primary slip plane in a fatigued \[1-34]-\[182-7] copper bicrystal with a Sigma=19b grain boundary (GB) have been investigated using the electron channelling contrast technique in a scanning electron microscope. The results show that the two-phase dislocation structure, such as veins and persistent slip band (PSB) walls, embedded within veins, can be clearly seen on the common primary slip plane. In particular, the interactions of PSBs with the GB are clearly revealed. It is found that there are three kinds of interaction mode between the GB and the dislocations during cyclic deformation, and those are discussed. It is suggested that the dislocations carried by PSBs cannot transfer through the GB continuously even though the bicrystal has a common primary slip plane and its surface slip bands are continuous across the GB. 相似文献
244.
Huaiyu Zhang Delishia M. Pittman Nicole L. Fischer Tomina J. Schwenke Erika R. Carr 《Journal of aggression, maltreatment & trauma》2013,22(5):501-519
Childhood maltreatment places individuals, including African American women who are undereducated and economically disadvantaged, at risk for developing posttraumatic stress disorder (PTSD) symptoms. Participants were 192 African American women with a history in the prior year of both a suicide attempt and intimate partner violence (IPV) exposure. They were recruited from a public hospital that provides medical and mental health treatment to mostly low-income patients. A simple mediator model was used to examine if (a) existential well-being (sense of purpose) or religious well-being (relationship with God) mediated the link between childhood maltreatment and adult PTSD symptoms. Sequential multiple mediator models determined if physical and nonphysical IPV enhanced our understanding of the mediational association among the aforementioned variables. Findings suggest that existential well-being mediated the association between childhood maltreatment and adult PTSD symptoms in a simple mediator model, and existential well-being and recent nonphysical IPV served as sequential multiple mediators of this link. However, religious well-being and physical IPV were not significant mediators. Findings underscore the importance of enhancing existential well-being in the treatment of suicidal African American women with a history of childhood maltreatment and IPV. 相似文献
245.
246.
采用家庭功能与同伴行为模式问卷和学习自我调节问卷,对913名青少年进行了测试。考察青少年同伴行为模式的发展特点,以及同伴行为模式在家庭功能与青少年学习自我调节关系中的中介作用。结果表明:青少年同伴行为模式对学习支持度随年级升高而下降;随年级升高,青少年在学习自我调节各维度上及总分的平均分越来越低;青少年的同伴行为模式可以正向预测学习自我调节,并在家庭功能与学习自我调节之间起部分中介的作用。家庭功能除直接影响学习自我调节外,还通过青少年的同伴行为模式间接影响他们的学习自我调节。 相似文献
247.
偏离行为的研究在社会学和组织行为学领域都有较丰富的成果,然而其关注点主要集中于对社会或组织产生负面作用的消极偏离行为。近年来相关领域的学者越来越关注积极偏离行为(Positive Deviance, PD)的研究。该文综述了关于积极偏离行为的定义的各方观点,同时分析了积极偏离行为与相似构念的差异,并综述了积极偏离行为的测量方式,以及积极偏离行为的前因变量和结果变量。最后对积极偏离行为未来的研究方向进行了展望。 相似文献
248.
Xiao Zhang Helena R. Slobodskaya Hitoshi Kaneko 《International journal of psychology》2024,59(1):64-73
This study examined associations between self-reported mental health problems, body image, bullying victimisation and school safety in large adolescent samples in Japan and Russia, considering the effects of gender, culture and their interactions. In both Japan and Russia, girls reported a greater number of mental health problems, less bullying victimisation and much higher body dissatisfaction than boys did. Japanese adolescents rated themselves higher on total difficulties, reported less body dissatisfaction and bullying victimisation, and rated their school safety lower than that of Russian youths. Cross-cultural differences in total difficulties and body image were qualified by gender. Body dissatisfaction, bullying victimisation and school safety all independently contributed to adolescent mental health problems. The protective effect of school safety on total difficulties was larger for girls than for boys; the strength of the association between bullying victimisation and adolescent mental health problems differed across genders and cultures. The findings indicate a need for a cross-cultural approach and provide a strong basis for targeted interventions that seek to improve adolescent mental health. 相似文献
249.
We contrast two approaches to probing the depth of theory-of-mind (ToM) reasoning by adults in matrix game settings: our own and that of Stahl and Wilson. 相似文献
250.
瑞文标准推理测验在我国的修订 总被引:36,自引:3,他引:36
为了满足科研与实际工作对团体智力测验的迫切需要,由17个单位组成的全国协作组对瑞文标准推理测验进行了修订。常模团体的建立以1982年全国人口普查资料为依据,按各地区人口分布,各类人员比例取样,共包括年龄跨度从5岁半至70岁以上的5108人。经过标准化的施测手续,测定了1986年中国城市常模。 测验结果的项目分析、信度和效度等技术指标达到或超过了国外同类研究。 研究发现除40岁组外,其他各年龄组均无显著男女差异。本研究还对中国大陆城市青少年的成绩与香港、英国和新西兰相应年龄组的成绩做了比较。 相似文献