The diffusion of moisture in sorbent solids part II. activated alumina     

Stanley H. Jury  Mark A. Pollock  Eul K. Kim 《Journal of The Franklin Institute》1977,303(5):425-436

Ordinary and thermal diffusion of moisture in activated alumina are investigated using a new diffusion cell design and scheme of analysis reported earlier. The specific form of the mass flux equation has a pronounced effect on the magnitude of the associated thermal diffusion ratio. In the case of activated alumina-moist air, if a partial pressure gradient is used, then the thermal diffusion term is small if not zero.Free, Knudsen and surface diffusion all play a part in the diffusion through activated alumina. However, surface diffusion makes the major contribution and for this reason the model in this case can be simplified to a two parameter surface model.The activation energy for surface diffusion is constant and is approximately equal to the mean isosteric heat of absorption. In addition, mean pore radius, turtuosity, and other physical constants are computed from the least square fit of experimental data. Furthermore, the model is theoretically consistent over the entire concentration range (0≦ C_A ≦ C_Asat).A new fact about activated alumina (Grade F1) it that it does not transfer moisture in a nonisothermal condition so long as the partial pressures of moisture on the two sides of the pellet are the same. There appears to be no previous report of this fact in the periodical literature.  相似文献   

Preface     

John Swift  Nick Stanley 《The International Journal of Art & Design Education》1999,18(1):1-6

  相似文献   

Teaching and Research Quality Indicators and the Shaping of Higher Education   总被引：4，自引：0，他引：4  

Patrick  William J.  Stanley  Elizabeth C. 《Research in higher education》1998,39(1):19-41

Two important sets of performance indicators have become established in the United Kingdom: research quality ratings and teaching quality ratings. The research quality ratings and, to a lesser extent, the teaching quality ratings, influence the level of government funding provided to higher education institutions. This paper considers the correlation between the two ratings and the possible consequences of policies that reshape the higher education sector by concentrating research resources in a limited number of institutions. Comparisons are made between quality assurance/assessment approaches in the United Kingdom and those in the United States.  相似文献   

Introducing technology education: Using teachers' questions as a platform for professional development     

Dr Sarah J. Stein  Cambell J. McRobbie  Ian S. Ginns 《Research in Science Education》1999,29(4):501-514

This paper explores the issues and concems identified by a small group of teachers implementing technology ideas using the national document,A Statement on Technology for Australian Schools (Curriculum Corporation, 1994a), represented in four key questions they posed as a result of reflection upon their existing ideas and practices, early in the study. These same issues and concerns framed their later experiences as the study progressed. The case study of one of the teachers is used, to illustrate how the teachers implemented technology education working from their own perspectives and tackling issues and concerns that made sense to them. By reviewing the teachers' own questions about technology implementation, it is becoming, clear that what may be important for professional development in technology education is related to the questions that the teachers themselves are asking about their own, beliefs and practices.  相似文献   

Resetting the Stage: Introducing a Special Section About Learning Sequences and Developmental Theory     

Zachary Stein 《Mind, Brain, and Education》2009,3(2):94-95

  相似文献   

On the Difference Between Designing Children and Raising Them: Ethics and the Use of Educationally Oriented Biotechnology     

Zachary Stein 《Mind, Brain, and Education》2010,4(2):53-67

The use of educationally oriented biotechnology has grown drastically in recent decades and is likely to continue to grow. Advances in both the neurosciences and genetics have opened up important areas of application and industry, from psychopharmacology to gene-chip technologies. This article reviews the current state of educationally oriented biological technologies, eventually focusing on the use of psychiatric drugs with children and adolescents to improve their academic performance. Distinguishing between “good” and “bad” uses of biological technologies is complicated by conflicting theoretical views about human development, the etiology of disability, and the diagnostic categories that structure treatments. To address these issues I introduce a set of ethical concepts, which are based on a biopsychosocial approach to human development. The difference between designing children and raising children marks an ethically salient difference between approaches that focus on only part of the child (e.g., her brain) and approaches that focus on the full biopsychosocial complexity of the developing child in context. This clarifies the importance of the child's right to both autonomy and care. Implications for policy and practice are offered.  相似文献   

Book reviews     

Peter Stanley 《高等教育研究与发展》2010,29(1):103-109

  相似文献   

Mathematics in early childhood: Teacher educators’ accounts of their work     

Kristin Lyn Whyte  M. Abigail Stein  Debbie Kim  Natalie Jou  Cynthia E. Coburn 《Journal of Early Childhood Teacher Education》2018,39(3):213-231

  相似文献   

Energy Cost of Rebound-Running     

Victor L. Katch  John F. Villanacci  Stanley P. Sady 《Research quarterly for exercise and sport》2013,84(2):269-272

Using Sonstroem, Harlow, and Josephs' (1994) expanded version of the Exercise and Self-Esteem Model (EXSEM; Sonstroem &; Morgan, 1989), we explored how 9 older adults (6 women and 3 men, aged 65–72 years) involved in a resistance training program experienced and perceived changes in physical self-worth (i.e., improved strength, functional competency, physical condition, and body satisfaction). We conducted three in-depth interviews with each participant over the course of the program. In individual log books, participants recorded the weight lifted and the number of repetitions for each exercise. Our findings showed the course of changes in physical self-perceptions in these older adults and how actual individual changes in strength performance related to perceived changes in important psychological outcomes.  相似文献   

Improving K-12 pedagogy via a Cloud designed for education   总被引：1，自引：0，他引：1  

Sarah Stein  Jennifer Ware  Johanne Laboy  Henry E. Schaffer 《International Journal of Information Management》2013

Cloud computing offers an opportunity to improve K-12 pedagogy with services tailored to teachers’ needs in individual classrooms. The Cloud can deliver services such as remote access to learning tools in a cost effective manner to school systems struggling with reductions in local and state funding. This article explores the distinct ways that a Cloud designed specifically for education can be applied to K-12 education's academic mission. It uses observations from a case study in North Carolina rural high schools using an educational Cloud called the Virtual Computing Lab to access dynamic geometry and algebra software.  相似文献