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41.
10 wt pct Ni steel is a high-strength steel that possesses good ballistic resistance from the deformation induced transformation of austenite to martensite, known as the transformation-induced-plasticity effect. The effects of rapid heating and cooling rates associated with welding thermal cycles on the phase transformations and microstructures, specifically in the heat-affected zone, were determined using dilatometry, microhardness, and microstructural characterization. Heating rate experiments demonstrate that the Ac3 temperature is dependent on heating rate, varying from 1094 K (821 °C) at a heating rate of 1 °C/s to 1324 K (1051 °C) at a heating rate of 1830 °C/s. A continuous cooling transformation diagram produced for 10 wt pct Ni steel reveals that martensite will form over a wide range of cooling rates, which reflects a very high hardenability of this alloy. These results were applied to a single pass, autogenous, gas tungsten arc weld. The diffusion of nickel from regions of austenite to martensite during the welding thermal cycle manifests itself in a muddled, rod-like lath martensitic microstructure. The results of these studies show that the nickel enrichment of the austenite in 10 wt pct Ni steel plays a critical role in phase transformations during welding.  相似文献   
42.
Cobalt disilicide is grown epitaxially on (100) Si from a 15 nm Co/2 nm Ti bilayer by rapid thermal annealing (RTA) at 900°C. Polycrystalline CoSi2 is grown on (100) Si using a 15 nm Co layer and the same annealing condition. Silicide/p+-Si/n-Si diodes are made using the silicide as dopant source:11B+ ions are implanted at 3.5–7.5 kV and activated by RTA at 600–900°C. Shallow junctions with total junction depth (silicide plus p+ region) measured by high-resolution secondaryion mass spectroscopy of 100 nm are fabricated. Areal leakage current densities of 13 nA/cm2 and 2 nA/cm2 at a reverse bias of -5V are obtained for the epitaxial silicide and polycrystalline silicide junctions, respectively, after 700°C post-implant annealing.  相似文献   
43.
Meeting the mental health needs of Veterans returning from recent deployment requires the coordinated effort of partnerships across Department of Defense (DoD), Department of Veterans Affairs (VA), and state and local communities. Although the proportion of Veterans of Iraq and Afghanistan who have accessed VA health care has grown, the majority of these new combat Veterans have yet to present for VA care. The stigma associated with reporting a deployment-related mental health problem may be one factor in this, but access to treatment may also be an important concern among the one third of American Veterans who live in rural or highly rural areas. As these Veterans are more likely to present to a primary care, faith-based or mental health provider in their own community, partnerships between community providers, DoD, and VA are of critical importance in ensuring appropriate care, regardless of treatment setting. In an effort to improve services and access to services, especially to rural Veterans, an educational public health initiative was created to educate community providers about military culture, deployment-related mental health issues, VA resources, and evidence-based treatments. We describe the development, dissemination and evaluation of this initiative, as well as lessons learned for future similar endeavors. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
44.
Raising an adolescent or adult child with a developmental disability confers exceptional caregiving challenges on parents. We examined trajectories of 2 indicators of emotional well-being (depressive symptoms and anxiety) in a sample of primarily Caucasian mothers (N = 379; M age = 51.22 years at Time 1) of adolescent and adult children with an autism spectrum disorder (ASD; M age = 21.91 years at Time 1, 73.2% male). We also investigated within-person associations of child context time-varying covariates (autism symptoms, behavior problems, residential status) and maternal context time-varying covariates (social support network size and stressful family events) with the trajectories of emotional well-being. Data were collected on 5 occasions across a 10-year period. Average patterns of stable (depressive symptoms) and improved (anxiety) emotional well-being were evident, and well-being trajectories were sensitive to fluctuations in both child and maternal context variables. On occasions when behavior problems were higher, depressive symptoms and anxiety were higher. On occasions after which the grown child moved out of the family home, anxiety was lower. Anxiety was higher on occasions when social support networks were smaller and when more stressful life events were experienced. These results have implications for midlife and aging families of children with an ASD and those who provide services to these families. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
45.
Several theoretical perspectives suggest that knowledge of children's perceptions of and beliefs about their parents' depression may be critical for understanding its impact on children. This paper describes the development and preliminary evidence for the psychometric properties of a new measure, the Children's Perceptions of Others' Depression – Mother Version (CPOD-MV), which assesses theoretically and empirically driven constructs related to children's understanding and beliefs about their mothers' depression. These constructs include children's perceptions of the severity, chronicity, and impairment of their mothers' depression; self-blame for their mother's depression; and beliefs about their abilities to deal with their mother's depression. The CPOD-MV underwent two stages of development: (1) a review of the literature to identify key constructs, focus groups to help generate items, and clinicians' ratings on the relevance and comprehensibility of the drafted items and (2) a study of the measure's psychometric properties. The literature review, focus groups, and item-reduction techniques yielded a 21-item measure. Reliability, factor structure, and discriminant, convergent, and concurrent validity were tested in a sample of 10- to 17-year-old children whose mothers had been treated for depression. The scale had good internal consistency; factor structure suggestive of a single construct; and discriminant, concurrent, convergent, and incremental validity, suggesting the importance of measuring children's perceptions of their mothers' depression beyond knowledge of mothers' depression symptom level when explaining which children have the greatest risk for emotional and behavioral problems among children of depressed mothers. These findings support continued development and beginning clinical applications of the scale. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
46.
The present intergenerational study examined the perceived impact of the recent U.S. economic crisis on a sample of 68 young adult–parent dyads. The relative contribution of perceived economic pressure, reports of adult child–parent relationship quality, and concerns about the economic future in accounting for variation in self-reports of psychological distress for adult children and their middle-aged parents were examined. Parents' concerns about their children's economic future accounted for variation in their reports of anxiety and depressed mood above and beyond that of perceived economic pressures and their views of the parent–child relationship. In contrast, for young adults, reports of personal economic pressure were generally related to self-reported anxiety and depressed mood. Implications of findings for research and practice are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
47.
Reports an error in Factor structure of the BASC–2 Behavioral and Emotional Screening System Student Form by E. Dowdy, et al. (Psychological Assessment. np). There was an omission in the author note. The author note should have included a disclosure as follows, “Randy W. Kamphaus wishes to disclose a potential conflict of interest in that he receives a portion of royalties on net sales of BESS.” (The following abstract of the original article appeared in record 2011-04578-001.) The BASC–2 Behavioral and Emotional Screening System (BESS) Student Form (Kamphaus & Reynolds, 2007) is a recently developed youth self-report rating scale designed to identify students at risk for behavioral and emotional problems. The BESS Student Form was derived from the Behavior Assessment System for Children—Second Edition Self-Report of Personality (BASC–2 SRP; Reynolds & Kamphaus, 2004) using principal component analytic procedures and theoretical considerations. Using 3 samples, the authors conducted exploratory factor analyses (EFA) and confirmatory factor analyses (CFA) to understand the underlying factor structure of the BESS Student Form. The results of the EFA suggested that the SRP contained a 4-factor (i.e., Personal Adjustment, Inattention/Hyperactivity, Internalizing, School Problems) emergent structure, which was supported by CFA in 2 additional samples. Practical and research implications are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
48.
Trained 192 Peking duck embryos (Anas platythynchos) in an operant escape task on Day 25 of incubation (total incubation period of 27 days) following decerebration on Day 24. Experimental embryos successfully acquired the operant response, which involved the performance of a discrete foot flexion to terminate a shock applied to the wing. The decerebrate embryos resembled normal unoperated embryos of this age in their acquisition of the operant behavior. Results demonstrate that this form of learning can be acquired without benefit of telencephalic structures, at least at this point in development. Differences in the consequences of decerebration during prenatal or neonatal vs adult stages are discussed. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
49.
Three cohorts of 10- to 14-year-old adolescents were sampled to obtain perceptions of their parents' conflict-resolution styles, their own conflict-resolution styles, and their behavioral adjustment, to test J. H. Grych and F. D. Fincham's (1990) cognitive-contextual model of the relationship of marital conflict to child adjustment. As found previously, boys and girls were not exposed to different levels or types of interparental conflict, although boys tended to blame themselves more. Adolescents' reports of their own conflict-resolution styles with siblings were clearly related to level and types of their more general adjustment levels. A series of regressions supported Grych and Fincham's model for internalizing problems (and avoidant resolution style) in adolescents; only minimal support was found with externalizing problems (and attacking resolution style). Gender-specific patterns of intergenerational transmission of resolution styles were found and are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
50.
Ninety-seven couples completed questionnaires about their involvement in joint religious activities and their perceptions regarding the sanctification of marriage, including perceived sacred qualities of marriage and beliefs about the manifestation of God in marriage. In contrast to individual religiousness and religious homogamy (distal religious constructs), these proximal religious variables directly reflect an integration of religion and marriage, and they were associated with greater global marital adjustment, more perceived benefits from marriage, less marital conflict, more verbal collaboration, and less use of verbal aggression and stalemate to discuss disagreements for both wives and husbands. The proximal measures also added substantial unique variance (adjusted R2 change ranged from .06 to .48) to specific aspects of marital functioning after controlling demographic factors and distal religious variables in hierarchical regression analyses. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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