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61.
A key challenge in the fabrication of superhard nanocomposite films is how to control the distribution of grain sizes in these materials. High-resolution transmission electron microscopy has been used to measure nanograin-size distributions in the Ti–B–N films with various B contents. The results show that the mean grain size decreases with increase of B content and the grain-size distribution conforms to a log-normal function when the hardness approaches a maximum value. The transition from normal to log-normal distributions can be determined by analysis in terms of a minimum information criterion. The origin of a log-normal size distribution probably results from heterogeneity arising from a diffusion-drift process.  相似文献   
62.
This article describes a design strategy deployed in developing ultra-ductile Mg alloys based on a microalloying concept, which aims to restrict grain growth considerably during alloy casting and forming. We discuss the efficiency of the design approach, and evaluate the resulting microstructural and mechanical properties. After processing, the so-designed alloys ZQCa3 (Mg–3Zn–0.5Ag–0.25Ca–0.15Mn, in wt.%) and ZKQCa3 (Mg–3Zn–0.5Zr–0.5Ag–0.25Ca–0.15Mn, in wt.%) reveal very fine grains (<10 µm), high ductility (elongation to fracture of up to 30%) at moderate strength or high strength (ultimate tensile strength of up to 350 MPa) at reasonable ductility. These properties are explained based on thermodynamic modelling, microstructure analysis including transmission electron microscopy studies, and microstructural and mechanical testing after annealing, and are compared to a related commercial alloy (ZK31).  相似文献   
63.
The effect of a high magnetic field on the morphology of the MnBi primary phase during the directional solidification has been investigated experimentally and the results show that an application of a high magnetic field has enhanced the faceted growth and the coarsening of the MnBi primary phase. This may be attributed to the effect of a high magnetic field on the diffusion of the solute Mn and the growth anisotropy of the MnBi crystal.  相似文献   
64.
ABSTRACT

This study examines the patterns and relationships between twelve independent variables and the expressed subjective well-being of older adults within that classic community setting of the Lynds' “Middletown.” The twelve variables include measures of church attendance, religious activity, religious conservatism/liberalism, subjective health status, social participation, importance of leisure, participation in physical activity, age, sex, marital status, and level of education.  相似文献   
65.
Coping is related to mental and physical health outcomes, but cultural and societal differences may influence its nature and structure. This study reports on the adaptation of the Coping Responses Inventory for Adult (CRI-A) to the Iranian social and cultural context. Study 1 was designed to obtain qualitative data and test the construct and discriminative validity of coping scales. Factor analysis of the CRI and Iranian items yielded seven factors: Religious Coping, Problem Solving, Cognitive Avoidance, Positive Reappraisal, Seeking Guidance and Support, Seeking Alternative Rewards, and Acceptance/Resignation. Internally, consistencies varied considerably from 0.92 to 0.53. All sub-scales from the Coping Responses Inventory for Adult (CRI-A) were resistant to social desirability biases with the exception of Religious Coping and Problem Solving. In Study 2, the replicability of the adapted CRI-A factorial structure and concurrent validity for the newly developed religious coping sub-scale was demonstrated. Given the importance of the role of religious coping in health and well-being outcomes, the expression and use of which may be substantially influenced by cultural practices and norms, it is recommended that future research pursues the validation of context-specific constructs of religious and spiritual coping.  相似文献   
66.
Forgiveness is a complex construct with an important role in religious traditions worldwide, and is associated with mental and physical health outcomes. This seven-year longitudinal study examined changes within individuals during, and differences based on birth cohort, in forgiveness during late life. Growth curve analysis was used to analyse the general pattern of change across the course of older adulthood in eight dimensions related to forgiveness. Increases over time were observed in forgiveness of others, conditionality of forgiveness of others, forgiveness of self, feelings of being forgiven by God, and feelings of being forgiven by others. Decreases over time were observed in difficulty forgiving oneself, and perceptions of conditionality in God's forgiveness. Religious commitment was related to reporting more a more forgiving attitude on seven of these dimensions, but also to more perceived conditionality in God's forgiveness. Finally, differences in mean levels of forgiveness emerged between birth cohorts.  相似文献   
67.
The growth and development of community psychology in Zambia has been necessitated by many social problems encountered by Zambians be they health, economic or psychological. The work of governmental and nongovernmental organizations at community level has contributed to the development of this sub-field of psychology. Community psychology in Zambia has many challenges to overcome, including the lack of trained manpower and availability of funds. Community psychology has great potential to contribute to the wellbeing of different communities in Zambia.  相似文献   
68.
Background: There is accumulating evidence that positive mental health and psychopathology should be seen as separate indicators of mental health. This study contributes to this evidence by investigating the bidirectional relation between positive mental health and psychopathological symptoms over time. Methods: Positive mental health (MHC-SF) and psychopathological symptoms (BSI) were longitudinally measured in a representative adult sample (N?=?1932) on four measurement occasions in nine months. A cross-lagged panel design was applied and evaluated with a latent growth model combined with an item response theory measurement model. Results: Psychopathological symptoms were longitudinally related to positive mental health and vice versa, controlling for initial levels. The changes over time were even more important than the absolute levels of psychopathological symptoms and positive mental health, respectively. Conclusions: The results underline the need for a comprehensive perspective on mental health, incorporating both the treatment of symptoms and the enhancement of well-being.  相似文献   
69.
Selection experiments and game theory models have revealed that the changes in agonistic behavior following selection for rapid growth rate of fish depend on the access of food. If food is spatially restricted and in excess of demand, the intensity of agonistic behaviors will decrease. This prediction was tested in an experiment on wild and sea‐ranched brown trout (Salmo trutta L.) fry originating from a common stock. Agonistic behavior, activity, and specific growth rate were studied in tanks (56 × 56 cm) at high (159.4 fry/m2) and low (9.6 fry/m2) stocking densities given either a large or small food ration (3.0% and 1.5%, respectively, food per total body weight and day). Observations were done during 4 days in each trial. Generally, fry of sea‐ranched origin had a higher growth rate. No differences in activity were found. Intensity of agonistic behavior was higher among wild groups. There was a tendency for interaction between density and strain, e.g., wild fish were relatively more aggressive at higher densities. Food ration had no effect on level of agonistic behavior. These results indicate that the selection for rapid growth in hatcheries may indirectly select for reduced aggressiveness. Genetic integrity and diversity of wild populations may be threatened when interbreeding occurs between wild and hatchery fish. Aggr. Behav. 28:145–153, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   
70.
This paper presents a latent growth SEM approach for the estimation of treatment effects, and power to detect such effects, within a true experimental design setting in which subjects are randomly assigned to treatment and control conditions. Power estimation is a critical component of intervention experiment design and the testing of their results. Although researchers have become increasingly sophisticated in applying tests for statistical significance in intervention contexts, few are aware of the power of these tests. The issues raised in this paper are not new; however, reminding researchers to consider these points is important. Exactly how the researcher handles these issues will depend on the questions asked and the resources available, as well as other considerations. Discussion underscores the relationship between the reliability of a study's measures and concomitant increases in power obtained within the SEM framework.  相似文献   
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