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91.
Molybdenum bismuth telluride thin films have been prepared on clean glass substrate using arrested precipitation technique which is based on self-organized growth process. As deposited MoBi2Te5 thin films were dried in constant temperature oven at 110°C and further characterized for their optical, structural, morphological, compositional, and electrical analysis. Optical absorption spectra recorded in the wavelength range 300–800?nm showed band gap (E g) 1.44?eV. X-ray diffraction pattern and scanning electron microscopic images showed that MoBi2Te5 thin films are granular, nanocrystalline having rhombohedral structure. The compositional analysis showed close agreements in theoretical and experimental atomic percentages of Mo4+, Bi3+, and Te2? suggest that chemical formula MoBi2Te5 assigned to as deposited molybdenum bismuth telluride new material is confirmed. The electrical conductivity and thermoelectric power measurement showed that the films are semiconducting with n-type conduction. The fill factor and conversion efficiency was characterized by photoelectrochemical (PEC) technique. In this article, we report the optostructural, morphological, compositional, and electrical characteristics of nanocrystalline MoBi2Te5 thin films to check its suitability as photoelectrode in PEC cell.  相似文献   
92.
Al–Pb ribbons containing 1?at.%?Pb have been produced by melt-spinning and subsequently investigated by high-resolution transmission electron microscopy. It is shown that the lattice mismatch of about 22% between the nanometre-sized Pb inclusions and the surrounding Al matrix is accommodated by a periodic array of misfit dislocations at the Al–Pb interface. The closing failures of Burgers circuits drawn around misfit dislocations on {111} and {100} facets identify the corresponding Burgers vectors as (a 0/4)? 211 ? and (a 0/2)? 110?, respectively. The Burgers vector of (a 0/4)? 211? corresponds to the projected edge part of a 60° (a 0/2)? 110? dislocation. The Pb inclusions themselves appear to be free of defects.  相似文献   
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94.
Gentrification changes the neighborhood and family contexts in which children are socialized-for better and worse-yet little is known about its consequences for youth. This review, drawn from research in urban planning, sociology, and psychology, maps out mechanisms by which gentrification may impact children. We discuss indicators of gentrification and link neighborhood factors, including institutional resources and collective socialization, to family processes more proximally related to child development. Finally, we discuss implications for intervention and public policy recommendations that are intended to tip the scales toward better outcomes for low-income youth in gentrifying areas.  相似文献   
95.
The paper reviews policies promoting faith-based organizations' (FBO) participation in publicly-funded programs since the Charitable Choice statute was enacted during the Clinton administration and then additional faith-based initiatives were implemented by the Bush administration. The paper focuses on research findings on FBO participation in publicly-funded human service programs under these policies. It then proposes a framework for evaluation to assess the appropriateness of public funding for behavioral health services delivered by FBOs, in order to address: (1) the programmatic and systemic effects resulting from the infusion of new players from the faith community, and the consequences to the profile of services and who gets served; and (2) the content and effectiveness of faith-infused services as a basis for identifying interventions appropriate for public funding. The analysis considers classification issues, theoretical bases of measured effects of faith-infused services, and the transferability of faith-based interventions across religious and secular applications in order to satisfy constitutional issues and client choice.  相似文献   
96.
Contributions to public goods are premised on the expectation that the collective will realize benefit in excess of the value of required contributions. However, past research has focused on public goods of fixed and known value, for which the added value of the produced public good is obvious. Research has largely ignored public goods whose eventual value is uncertain at the time contribution decisions are made. Two studies explored the effects of outcome variance on individuals’ contributions to a public good and their reasons for contributing. Contributions were negatively affected by loss prospects in the distribution of possible outcomes. Further, loss prospects directly discouraged contributions because of loss aversion, and indirectly discouraged contributions by fueling fears that others would not contribute. The negative effects of loss prospects were stronger when social uncertainty was low. Implications for social dilemma research and the effective management of collective action are discussed.  相似文献   
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98.
Public speaking is a highly prevalent fear that prevents from successful social communication. The Personal Report of Confidence as a Speaker (PRCS) is one of the most commonly used measures to assess people’s fear of public speaking. However, few studies have evaluated its factor structure. In this paper, two studies analyzed the psychometric properties of the short form of the PRCS (Hook, Smith, & Valentiner, 2008) and its convergent validity with the Self Statements During Public Speaking (SSPS) scale in Spain. Study 1 (N = 190) provided information about exploratory factor analysis and internal consistency. Study 2, with a different sample (N = 392), complemented Study 1 with confirmatory factor analysis, internal consistency, convergent validity with SSPS and test of measurement invariance across gender groups. Results of exploratory factor analysis yielded a one factor solution. Different indices of the confirmatory factor analysis (CFI, TLI, SRMR, RMSEA) confirmed a good fit. Internal consistency was high in both studies and convergent validity with SSPS was found. Evidence of configural, metric and scalar invariance across gender groups was obtained. These findings support the use of the short form of the PRCS and suggest that it is a useful instrument for public speaking assessment.  相似文献   
99.
Research on online support forums has largely overlooked the quality of support provision. The present experiment examined how others' responses and a support-seeker's reply can influence action‐focused supportiveness, emotion‐focused supportiveness, and politeness of readers' support messages. Results showed that the supportiveness of others' comments was associated with subsequent readers' perceptions of public opinion toward the support‐seeker and readers' liking of the support‐seeker, which in turn influenced the quality of readers' support messages.  相似文献   
100.
In four experiments conducted on the world wide web, subjects evaluated the priority of policies presented separately or presented jointly in pairs, and/or reported their emotional responses to the problem that each policy addressed. Strength of emotional responses was more strongly related to priority when policies were presented separately than when they were presented jointly. We found evidence for one mechanism that could produce these results: joint presentation increases the evaluability of the policies, thus increasing the influence of cognitive evaluations of importance on priority judgements, and reducing the relative influence of emotional responses. We also found evidence that importance can affect emotional responses. We found no evidence for other mechanisms in which the emotions evoked by one item spread to the other item in joint presentation. The role of evaluability points to the applied value of evaluating policies in the context of alternatives.  相似文献   
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