Solidification thermal parameters,microstructural evolution and dendritic growth in an AlCuNi alloy

ABSTRACT

Unsteady-state upward solidification experiment was carried out with the Al-3Cu-3Ni (wt.%) alloy. Temperature profiles were obtained through a water-cooled directional solidification device. Analysis on the resulting as-cast microstructure and its adaptation to thermal solidification parameter, such as growth and cooling rates and solidification local time, V_L, T_R and t_SL, respectively, was carried out. The results showed that the resulting microstructure is constituted by an Al-rich primary phase (Al _α ), characterised by a dendritic network, and by second phases that take place within the interdendritic regions, forming a eutectic mixture composed by the β-Al₃Ni?+?θ-Al₂Cu intermetallic compounds (IMCs), whose size and morphology have been affected by V_L and T_R. The length of the microstructural scale of the Al _α phase was measured by the secondary dendritic spacing (λ ₂). The experimental mathematical expression of λ ₂ obtained in this work was compared with mathematical models proposed in the literature that associate t_SL-λ ₂ for non-equilibrium and equilibrium solidification conditions.     

Career support needs of learners with historical disadvantage: an exploratory study

This study explored the career support needs of learners from a historically disadvantaged rural South African school setting. Participants were a convenience sample of 20 high school learners (females=60%; males=40%; age range 15–17 years; schools grades 9–10). They completed focus group interviews relating to their career awareness and needs. The data were thematically analysed. The results suggested learners have significant in-school career awareness and support needs. The learners accessed career related information informally from social networks they were using out of school rather than in the educational setting.     

Addressing Cultural Factors in Development of System Interventions

SUMMARY

The purpose of this article is to address various issues concerning multicultural interventions at a system level. Diversity is presented through a different conceptual approach and specific implications for school psychological practice are addressed. In this theoretical context an alternative model of school psychological services that was developed in the Greek educational system is presented and a primary intervention program is described as a paradigm of multicultural system/community intervention. Finally, the components of a transnational approach to multicultural system/community interventions that provides the basic procedural guidelines to developing effective, culturally sensitive interventions in the school environment is proposed.     

Philosophy of Education as an Academic Discipline in Turkey: The Past and the Present

This article aims to present the past and present state and future possibilities of philosophy of education as an academic discipline in Turkey as related to teacher training programs and academic studies in higher education institutions. It takes philosophy of education as consisting of the approaches that have emerged in its history. It has come to Turkey as a part of the modernization of education. It seems that during the Republican era in Turkey before World War II, mainly due to the dominance of the German conception of educational studies, the pedagogy and the history of pedagogy courses and the textbooks for them, which were central to the curricula of teacher training schools, contained the subjects of philosophy of education in its continental form; and after World War II philosophy of education is mostly understood, primarily due to Turkey’s changing international relations and the spread of American influence, as the isms and the doctrines approaches as found in the USA between the 1940s and 1960s, while other approaches in the field have been less influential. The article identifies how the restructuring of the teacher training system and the curricula of Faculties of Education in 1998 was a serious blow to the discipline, since it excluded philosophy of education from the curricula of teacher preparation schools, and the flourishing discipline thus lost its hold and importance in the undergraduate programs, and then in graduate programs. But the 2006 revision of the curricula has given a kiss of life to the discipline. There are reasons to think that it can recover in the coming period.

An Examination of the Effects of Repeated Readings with Secondary Students

Reading is a fundamental skill for success in school and as an adult. However, many children and adults experience difficulties reading. Previous research has demonstrated that repeated readings is an effective intervention for increasing both fluency and comprehension for elementary age readers of all skill levels. However, the impact of repeated readings on fluency and comprehension has not been examined with secondary students with reading deficits. The purpose of this study was to examine the effectiveness of repeated readings for increasing four secondary student's fluency on passages at their instructional level, at the ninth grade level, and on generalization passages from their school curriculum. Furthermore, the effects on comprehension were also explored. A comparison group of average readers served as an estimate for how fluently secondary students read. The results of this study demonstrated that fluency improvements were achieved for all of the participants with just ten additional hours of practice. Effects on comprehension were not as clear. Limitations and future directions for research are discussed.     

Prolegomena to any Future History of Analytic Philosophy

Abstract: The careful historical and metaphilosophical attention recently bestowed upon analytic philosophy has revealed that traditional ways of defining it are inadequate. In the face of this inadequacy, contemporary authors have proposed new definitions that detach analytic philosophy from its turn of the twentieth century origins. I argue that this contemporary trend in defining analytic philosophy is misguided, and that it diminishes the likelihood of our coming to an accurate historical and metaphilosophical understanding of it. This is especially unsatisfactory since such understanding is essential to finding an adequate remedy for the widely perceived ills of contemporary analytic philosophy. I suggest that a more fruitful approach to developing such understanding might begin with treating the unity of analytic philosophy as illusory.     

终生控制理论:关于人的整个生命历程的动机理论

终生控制理论提出控制是人类发展的动机系统,其目的是促进人的生存与发展并达到最优化。本文详细介绍了终生控制理论的核心概念：初级控制和二级控制、二者的功能及相互关系,以及有关研究与争论。     

Secondary Beliefs: A Mediator between Illness Representations and Coping Behavior in Arthritis Sufferers

The aim of the current study was to investigate the factors of secondary beliefs and illness representations, and their relationship with particular coping strategies used in the management of arthritis, and more specifically, if secondary beliefs, as defined in Rational Emotive Behavioral Therapy (REBT), mediated the relationship between illness representations and coping, as outlined by the Self-Regulatory Model (SRM). A sample of 63 arthritis sufferers aged between 32.0 and 100.1 years was recruited. Participants were asked to complete three questionnaires: Ways of Coping Questionnaire (WOCQ); revised Illness Perception Questionnaire (IPQ-R); Secondary Beliefs Scale (SBS). Analyses revealed that all eight coping strategies measured were significantly related to one or more illness representation, lending support to the SRM. Furthermore, secondary beliefs were found to mediate the relationship between illness representations and coping for three of the strategies measured: confrontive coping, accepting responsibility and seeking social support, while they also appeared to be directly related to the escape-avoidance strategy. Therefore, support for the REBT model was also evidenced. Overall, these results have highlighted the importance of cognitive factors in influencing coping behavior, a finding that could prove useful when designing interventions aiming to promote beneficial coping in arthritis sufferers.