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61.
K. Saito T. Sasaki S. Sugawara J.Q. Guo A.P. Tsai 《Philosophical Magazine Letters》2013,93(5):307-315
Faceted micropits obtained by electrochemical etching of a single quasicrystal of an Al-Pd-Mn icosahedral phase have been examined by optical and electron microscopy. Anodic etching of the flat surface of a fivefold plane in a solution composed of CH3OH and HNO3(3:1 in volume ratio) reveals a variety of icosahedrally faceted micropits which originated from pre-existing microvoids and etch pits of pentagonal pyramid shape due to the other origins, probably structural defects inside the specimen. As the dissolution progresses, the micropits make successive changes in their shapes, ending in pentagonal pyramids before they vanish. 相似文献
62.
It is interesting to investigate the formation of He bubbles in amorphous alloys because point defects do not exist in amorphous materials. In the present study, the microstructural evolution of amorphous Fe79B16Si5 alloy, either irradiated with 5?keV He+ ions or implanted with 150?eV He+ ions without causing displacement damage, and then annealed at a high temperature, was investigated using transmission electron microscopy (TEM). Vacancy-type defects were formed in the amorphous alloy after irradiation with 5?keV He+ ions, and He bubbles formed during annealing the irradiated samples at high temperature. On the other hand, for samples implanted with 150?eV He+ ions, although He atoms are also trapped in the free volume, no He bubbles were observed during annealing the samples even up to 873?K. In conclusion, the formation of He bubbles is related to the formation and migration of vacancy-type defects even in amorphous alloys. 相似文献
63.
The microstructure and crystallization behaviour of melt-spun Al88Ni9Ce2Fe1 amorphous alloy and nanophase composites have been studied by means of X-ray diffraction, transmission electron microscopy and scanning and isothermal calorimetry. The diffraction patterns from Al88Ni9Ce2Fe1 amorphous alloys are diffuse, indicating a basically amorphous structure but contain two rings presumed to be associated with quenched-in nuclei. In the cases of Al88Ni9Ce2Fe1 nanophase composites, nanoscale precipitated particles are homogeneously dispersed in an amorphous matrix, and the crystallite diameter and volume fraction are sensitive to quenching conditions. During thermal crystallization, a two-step phase transformation occurs in the amorphous alloy and nanocomposites, which is characterized by a diffusion-controlled precipitation of nanoscale Al particles and the growth of a Al3(Ni, Fe) nanophase prior to a Al11Ce3 nanophase. This study gives insight into structure-control for obtaining nanophases dispersed in an amorphous matrix by rapid quenching. 相似文献
64.
Jacques Vermeulen Q. Michael Temane Ernst J. van der Merwe 《Journal of Psychology in Africa》2013,23(4):557-560
The aim of this research was to explore a group of black South Africans' experiences of telling their untold stories of survival about the apartheid era. The expectation was that if they did become more aware of these alternative stories, it could have a far-reaching effect on their lives. A qualitative study was conducted with a group of seven black South African survivors of the apartheid era, ranging in age from 42–62 years (males =5, females =2). These participants formed part of an earlier study investigating their perceptions regarding factors that helped them to survive the apartheid era. For the present study, unstructured interviews were conducted focusing on their subjective experiences after the initial study. Analysis of the data yielded seven prevalent themes, namely a positive experience that made a difference, gaining of a positive attitude, not all white people are bad, transgressing the past and moving on, awareness of personal strengths, forgiveness and starting to talk to family and friends. The participants became aware of their untold stories of survival and experienced a positive change within themselves, towards others, the past and the future. 相似文献
65.
Itumeleng P. Khumalo Q. Michael Temane Marié P. Wissing 《Journal of Psychology in Africa》2013,23(1):13-22
This study aimed to develop and validate the General Psychological Well-being Scale (GPWS) in an African sample, based on the empirical overlap between hedonic and eudaimonic facets of well-being as found in previous research. The quantitative cross-sectional study was conducted in three phases: secondary data analysis (n = 2005), pilot study (n = 296) and main study (n = 459). The pilot and main study included the GPWS as well as other psychological well-being measures for criterion-related validity. The pilot study yielded satisfactory psychometric properties. The main study yielded a high, reliable Cronbach alpha of.89 and evidence of construct validity. The GPWS appears to be a unidimensional scale suitable for research use with Setswana-speaking people. 相似文献
66.
Kimberly M. Burkhart Michele Knox Jeanne Brockmyer 《Journal of child and family studies》2013,22(7):942-951
Research documents that parents play a critical role in the development and maintenance of behavior problems in children. Few bullying prevention programs, however, target children in early childhood or include a parenting component in spite of experts recommending that parent training in behavior management be addressed. Based upon these recommendations, the present study examines the relationship among parent characteristics (hostility, depression, and overall parenting skills) and child bullying and the effects of the American Psychological Association’s ACT Raising Safe Kids program on reducing early childhood bullying. The ACT-RSK program is a primary family violence and child physical abuse prevention program for parents of young children. Fifty-two parents/caregivers, representing children ages 4–10, completed the Brief Symptom Inventory, the ACT Parents Raising Safe Kids Scale, and Early Childhood Bullying Questionnaire (derived from the Child Behavior Checklist and Strengths and Difficulties Questionnaire). Twenty-five of these parents/caregivers were trained in effective parenting including nonviolent discipline, child development, anger management, social problem-solving skills, effects of violent media on children, and methods to protect children from exposure to violence through the ACT-RSK program. The remaining 27 parents/caregivers received treatment as usual. Results indicate decreased bullying in children whose parents completed the ACT-RSK program. Furthermore, of the parent characteristics assessed, parental hostility is the only significant parent predictor for child bullying. These findings suggest the efficacy of this brief intervention for preventing bullying. 相似文献
67.
Michele Knox Kimberly Burkhart Sadik A. Khuder 《Journal of aggression, maltreatment & trauma》2013,22(7):800-811
Parental hostility and parental depression are associated with childhood behavior problems, but these have been studied independently in the literature. This study examined the relationships between parental hostility and depression and childhood aggression and conduct problems. Parental hostility was hypothesized to predict children's current and future (two months later) aggression and conduct problems. Participants were primary caregivers of children 0 to 10 years of age. Results indicate that hostility is a better predictor of present and future childhood aggression and conduct problems than depression. Implications of this finding for preventing and treating childhood aggression and conduct problems are discussed. 相似文献
68.
Exploring the Validity of the Values-In-Action Inventory of Strengths (VIA-IS) in an African Context
Itumeleng P. Khumalo Marie P. Wissing Q. Michael Temane 《Journal of Psychology in Africa》2013,23(1):133-142
This study explored the validity of the Values-In-Action Inventory of Strengths (VIA-IS) in an African context. A convenience sample of 256 African students completed the VIA-IS in English. The majority of strengths subscales had good reliability coefficients and mean scores comparable to those reported in a Western context. Satisfactory criterion-related validity was established through correlations with other well-being indices. First and second order confirmatory factor analyses only partly supported construct validity. All strengths subscales consisted of more than one factor. The hypothesised six-virtue cluster pattern was partially supported. Exploratory factor analysis suggested the possibility of an emic factor pattern of strengths consisting of 3 components: Within the first factor, Intrapersonal and Relationship Strengths, two clusters are distinguished, namely, Intrapersonal Strengths, and Horizontal and Vertical Relationship Strengths. The second factor was Integrity in Group Context. Thus, the VIA-IS has merit, but is not completely valid in its original form. 相似文献
69.
The aim of this study was to determine whether gender moderates the relationship between spirituality and psychological well-being. A secondary data analysis based on a cross sectional survey was implemented. A convenience sample of 508 participants (males = 143, females = 365; age range 18–65 with 66% in the 18–25 category) from the North-West Province of South Africa completed questionnaires on spirituality and psychological well-being after informed consent was obtained. Findings show that gender moderates the relationship between spirituality and psychological well-being. This moderation effect was stronger in the case of existential well-being rather than religious well-being as components of spiritual wellbeing, and also stronger in one of the sub-groups. Future studies may explore the role of contextual factors such as cultural orientation and other socio-demographic variables in this moderation effect, as well as gender based perceptions and practices of spirituality with a view to facilitate gender sensitive psychological well-being programmes. 相似文献
70.
Stephanie D. Stepp PhD Jennifer Q. Morse PhD Kirsten E. Yaggi MSW Sarah K. Reynolds PhD L. Ian Reed MA Paul A. Pilkonis PhD 《Suicide & life-threatening behavior》2008,38(5):592-607
The relationships among adult attachment styles, interpersonal problems, and categories of suicide‐related behaviors (i.e., self‐harm, suicide attempts, and their co‐occurrence) were examined in a predominantly psychiatric sample (N = 406). Both anxious and avoidant attachment styles were associated with interpersonal problems. In turn, specific interpersonal problems differentially mediated the relations between attachment style and type of suicide‐related behaviors. These findings suggest the importance of distinguishing between these groups of behaviors in terms of etiological pathways, maintenance processes, and treatment interventions. 相似文献