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The electronic structures of the μ phase of Co7Mo6 were investigated by means of first-principles calculation based on the density functional theory. The calculated equilibrium lattice parameters of Co7Mo6 are in good agreement with the experimental results. The results of calculation reveal that the addition of tungsten (W) promotes the stability of the μ phase of Co7Mo6 and W tends to participate in its formation. Through analysing the calculated electronic structure (partial density of states and charge density difference), it can be noted that a strong interaction exists due to d–d hybridization. Also, the majority of the atoms may contribute their valence electrons to the formation of metallic bonds in binary and ternary systems. Furthermore, the calculated results show that the doped W atom prefers to occupy the Co site in Co7Mo6 μ phase.  相似文献   
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Work in the field of multiple criteria analysis has generally focused on evaluation procedures, taking as its starting point a well-defined problem with specified alternatives and criteria. However, in reality, problems are rarely so well-structured; hence, in order to usefully support decision making in practice, multiple criteria analysts need to address the issue of problem structuring. In this respect, much can be learned from the body of work stemming from operational research and systems in the U.K., known collectively as problem-structuring methods. In this paper we describe a study which sought to integrate one of these approaches, SODA (strategic options development and analysis), using the COPE software for cognitive mapping, with multiple criteria evaluation based on a multi-attribute value function using V·I·S·A. The study took the form of a 2 day action research workshop to explore the strategic direction of the Supplies and Commercial Services Department of a large U.K. NHS Hospital Trust and to develop an action plan consistent with the agreed direction. Even though the workshop was intended to be exploratory, from the point of view of both the facilitators and the participants, it enabled the group to make progress towards the definition of a strategic direction and led to an increased understanding and awareness of the issues. Drawing on this experience, we comment in general on the potential benefits arising from the integration of these two approaches and suggest fruitful areas for future research and development of the software tools and associated methodologies. © 1997 by John Wiley & Sons, Ltd. J. Multi-Crit. Decis. Anal. 6 : 115–130 (1997) No. of Figures: 9. No. of Tables: 0. No. of References: 37.  相似文献   
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Stepfamilies are an increasingly common family form, many of which are headed by a resident mother and stepfather. Stepfather–child relationships exert notable influence on stepfamily stability and individual well‐being. Although various stepfather roles have been observed, more research is warranted by which stepfather–child interactions are explored holistically and across a variety of life domains (e.g., recreational, personal, academic, and disciplinary). Thus, the primary purpose of the current study is to explore varying interactional patterns between youth and their stepfathers. A latent class analysis is conducted using a representative sample of 1,183 youth (53% female; mean age = 15.64 years, SD = 1.70 years; 62% non‐Hispanic White) residing in mother–stepfather families from Wave I of the National Longitudinal Study of Adolescent to Adult Health. Latent‐class enumeration processes support a four‐class solution, with latent classes representing inactive, academically oriented, casually connected, and versatile and involved patterns of youth–stepparent interaction. Notable differences and similarities are evident across patterns with respect to family relationship quality, youth well‐being, and socio‐demographic characteristics. Differences are most stark between the inactive and versatile and involved patterns. Ultimately, the results showcase notable variation in youth–stepparent interactional patterns, and one size does not necessarily fit all stepfamilies. Family practitioners should be mindful of variation in youth–stepparent interactional patterns and assist stepfamilies in seeking out stepparent–child dynamics that are most compatible with the needs and dynamics of the larger family system.  相似文献   
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Informed by dyadic approaches and culturally informed, ecological perspectives of marriage, we applied an actor–partner interdependence mediation model (APIMeM) in a sample of 120 Mexican‐origin couples to examine (a) the associations linking Mexican immigrant husbands’ and wives’ gender role attitudes to marital satisfaction directly and indirectly through marital processes (i.e., warmth and negativity) and (b) whether the associations between spouses’ gender role attitudes and marital processes were moderated by wives’ employment. Although previous research has identified spouses’ gender role attitudes as potential predictors of spouses’ marital satisfaction, no study has examined these links in a dyadic model that elucidates how gender role attitudes may operate through processes to shape marital satisfaction and conditions under which associations may differ. We found that when spouses reported less sex‐typed attitudes, their partners reported feeling more connected to them and more satisfied with the marriage, regardless of whether wives were employed. Our results suggest that marital satisfaction was highest for those Mexican‐origin couples in which marital partners were less sex‐typed in their attitudes about marital roles to the extent that partners’ attitudinal role flexibility promoted spouses’ feelings of warmth and connection to their partner.  相似文献   
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Coparenting between biological parents is a strong predictor of child adjustment. To date, however, little is known about the coparenting dynamics between parent and stepparent in stepfamilies. This study aimed at exploring the links between coparenting in the mother–stepfather dyad and child behavior in stepfamilies compared with the links between mother–father coparenting and child behavior in first‐marriage families. Two modes of coparenting were assessed: overt coparenting, that is, coparental behaviors in the presence of the child, and covert coparenting, that is, the way each parent speaks of the other parent to the child. The sample (= 80) comprised 48 stepfamilies and 32 first‐marriage families with a child between 7 and 13 years old. Overt coparenting was assessed through direct observation in the standardized situation of the PicNic Game. Covert coparenting and child behavior were assessed through mother‐reported questionnaires. Results showed (a) more covert coparenting behaviors in first‐marriage families, (b) no differences in overt coparenting, (c) more child difficulties reported in stepfamilies, (d) less optimal overt coparenting being linked with more difficulties in children in both family structures, and (e) an interaction effect between family structure and coparenting, showing that overt coparenting is linked with child behavior mainly in stepfamilies.  相似文献   
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