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231.

The structures of HgBa3Ca4Cu4O10+ delta(Hg-1234) samples have been characterized by means of high-resolution electron microscopy, electron diffraction, X-ray energy-dispersive spectroscopy (XEDS) and electron-energy-loss spectroscopy (EELS) techniques. A modulated structure with a modulation vector of q = (0.036-0.048) b* + 0.5c* was found for Hg-1234. High-resolution electron microscopy on the modulated structure revealed slight displacements of atomic layers along the c direction. The anomalous contrast induced by the modulation was observed to be distributed asymmetrically between the HgOdelta layers, leading to the breakdown of the (001) mirror symmetry of the basic structure. XEDS compositional analyses showed a depletion of mercury for the modulated Hg1234 compared with the unmodulated Hg-1234, while EELS analysis suggested the presence of carbon in the modulated Hg-1234 phase. In addition, a sidecentred ordered (Cu, Hg)-1223 phase with low mercury content was identified as one of the major impurity phases in the Hg-1234 samples.  相似文献   
232.
In this study, the precipitate characteristics and selected area diffraction patterns (SADP) of the β?′ and Q?′ precipitates formed at the over-aged state of Al–Mg–Si–Cu alloys are systematically investigated by means of high-resolution transmission electron microscopy and transition matrix. The β?′ precipitates have two cross-sections, rectangle-shaped and round-shaped aligned with [0?0?1]Al direction, but only rectangle-shaped cross-section exists for Q?′ precipitates. And, both of them have 12 variants and orientations with Al matrix. However, there are only three different zone axes, [0?0?0?1]β?′, [1?4?5?0]β?′, and [5?4?1?0]β?′ for β?′ precipitates, and [0?0?0?1]Q?′, [1?4?5?0]Q?′, and [3?2 1?0]Q?′ for Q?′ precipitates, parallel to the [0?0?1]Al direction when they are precipitated from the Al matrix, respectively. Then, a new [0?0?1]Al SADP model, which superposes diffraction patterns of the β?′ and Q?′ precipitates, is established. Furthermore, some “cross-shaped” diffraction streaks appeared at over-aged state can be explained reasonably by this model, which is good in agreement with the experimental data.  相似文献   
233.
Researchers and practitioners conduct multi-informant assessments of child and family behavior under the assumption that informants have unique perspectives on these behaviors. These unique perspectives stem, in part, from differences among informants in the settings in which they observe behaviors (e.g., home, school, peer interactions). These differences are assumed to contribute to the discrepancies commonly observed in the outcomes of multi-informant assessments. Although assessments often prompt informants to think about setting-specific behaviors when providing reports about child and family behavior, the notion that differences in setting-based behavioral observations contribute to discrepant reports has yet to be experimentally tested. We trained informants to use setting information as the basis for providing behavioral reports, with a focus on parental knowledge of children’s whereabouts and activities. Using a within-subjects controlled design, we randomly assigned 16 mothers and adolescents to the order in which they received a program that trains informants to use setting information when providing parental knowledge reports (Setting-Sensitive Assessment), and a control program involving no training on how to provide reports. Relative to the control program, the Setting-Sensitive Assessment training increased the differences between mother and adolescent reports of parental knowledge, suggesting that mothers and adolescents observe parental knowledge behaviors in different settings. This study provides the first experimental evidence to support the assumption that discrepancies arise because informants incorporate unique setting information into their reports.  相似文献   
234.
This study examined the relationship among child maltreatment, parental bonding, and a lifetime history of major depressive disorder (MDD) in a sample of 119 Latino students. Forty-five students reported a lifetime history of MDD and 74 reported not having a lifetime history of MDD. The results indicated that emotional abuse and maternal overprotection were significantly associated with having a lifetime history of MDD. The findings support the importance of examining these factors among depressed Latinos. Future research should continue to explore both the role of child maltreatment and parental bonding in relation to a lifetime history of MDD in this population.  相似文献   
235.
品牌印象是消费者基于对品牌信息的感知和体验而在头脑中留下的品牌部分或整体信息。在文献研究和关键事件访谈的基础上,通过筛选条目、形成初步问卷、预测验和正式测验等程序,经探索性因素分析和验证性因素分析,重测信度、聚合效度、辨别效度、法则效度和效标关联效度等检验,发现全方位的品牌印象由品牌质量印象、品牌传播印象、品牌服务印象和品牌价格印象等四个维度构成。用于测量品牌印象的多维量表、各维单项目量表和单项目量表均具有较好的信度和效度。  相似文献   
236.
Since the 1950s, there has been a systemic development of research on creative personality. Three themes are apparent in this literature: individual differences of creative people, the construct of creative personality, and longitudinal studies about creative personality. However, little research has been conducted in any of these areas with Chinese samples, and the purpose of this study is to study the construct of Chinese adolescents' creative personality. Confirmatory factor analyses were conducted with data from 1,300 Chinese adolescents. The results provide evidence that adolescents' creative personality consists of three largely independent dimensions: Internal, External, and Self. The internal factor includes self-confidence, norm-doubt, internal motivation, and persistence; the external factor includes curiosity, risk-taking, openness and independence; the self factor pertains to self-acceptance.  相似文献   
237.
In recent years, the social sciences have seen a resurgence in the study of divergent thinking (DT) measures. However, many of these recent advances have focused on abstract, decontextualized DT tasks (e.g., list as many things as you can think of that have wheels). This study provides a new perspective by exploring the reliability and validity evidence for several methods for scoring real-world DT tasks (i.e., tasks situated within a real-world problem or situation). The results suggest a combination of objective and subjective scoring methods may be optimal for originality scoring for contextualized DT tasks, which stands in contrast to recent research suggesting the objective, percentage scoring technique may be optimal for scoring originality on abstract tasks.  相似文献   
238.
This article aims to summarize the current ethical issues in the field of clinical and counseling psychology and the process of developing professional ethical standards in China. First, through a review of the history of counseling and psychotherapy in China, general background information is provided. Important ethical issues are then discussed based on the results from several empirical studies. Finally, the process of developing the new edition of the Chinese Psychological Society Code of Ethics for Clinical and Counseling Psychology, the main contents as well as the considerations taken into account in the development of this code are presented.  相似文献   
239.
240.
This article is concerned with using the bootstrap to assign confidence intervals for rotated factor loadings and factor correlations in ordinary least squares exploratory factor analysis. Coverage performances of SE-based intervals, percentile intervals, bias-corrected percentile intervals, bias-corrected accelerated percentile intervals, and hybrid intervals are explored using simulation studies involving different sample sizes, perfect and imperfect models, and normal and elliptical data. The bootstrap confidence intervals are also illustrated using a personality data set of 537 Chinese men. The results suggest that the bootstrap is an effective method for assigning confidence intervals at moderately large sample sizes.  相似文献   
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