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111.
112.
The goal of this study was to examine the means used by textbook authors to introduce, define, and explain the mole concept in high school and introductory college chemistry textbooks. The analysis was framed by four questions:
  • 1 How is the mole defined?
  • 2 What concepts about the atom are introduced prior to the mole?
  • 3 Is Avogadro's constant presented as an experimentally determined value?
  • 4 What is the context for introducing the mole?
Twenty-nine high school and introductory college level chemistry texts were examined. After independent reading of appropriate sections of each text, discussion of differences, second or third readings of texts, and subsequent discussions, both authors reach 100% agreement concerning the results. Major conclusions were
  • 1 Two ways of defining the mole dominate the texts. One way defines the mole as Avogadro's number (6.02 × 1023) particles; the other method defines the mole in terms of carbon-12.
  • 2 All texts that present a definition in terms of C-12 introduce and define concepts about the atom prior to introducing the mole.
  • 3 Most texts at all levels point out that the value 6.02 × 1023 is an experimentally determined quantity.
  • 4 Nearly all texts discuss the mole in relation to die problem of finding a way to count particles that are too small to be directly weighed. Most texts also use a familiar counting unit, such as the dozen, to introduce the mole by analogy.
Four issues were discussed: (a) the defining attributes of the mole concept itself and the cognitive requirements for comprehending the two most frequently used definitions; (b) the connection between the definition of the mole presented in the text and the concepts about atoms that are introduced before the mole concept is developed; (c) the experimental nature of Avogadro's number; and (d) the context or setting for developing the mole concept.  相似文献   
113.
114.
On 14 May 1987, the Education Ministers of the Twelve reached agreement on the European Community Action Scheme for the Mobility of University Students (ERASMUS). With a total of 85 million ECU** ** One ECU is worth approximately $ 0.8131 United States dollars. View all notes earmarked for its initial phase (1 July 1987 to 30 June 1990), the programme will aim at encouraging increased student and staff mobility throughout the European Community by means of the creation of a European University Network, the award of grants to individual students, arrangements for the mutual recognition of qualifications and courses or parts of courses, and a range of additional supporting measures. In the following article, the authors will examine, in some detail, the Actions provided for in the Programme, which was formally adopted by the Council on 15 June 1987.

  相似文献   

115.
The paper reviews the lessons of planning and running an Engineering Management practitioner development programme in a partnership between BP and the University of Manchester. This distance-learning programme is for professional engineers in mid-career experienced in the engineering and support activities for delivering safe, compliant and reliable projects and operations worldwide. The programme concentrates on the why and how of leadership and judgement in managing the engineering of large and small projects and operational support. Two intensive residential weeks are combined with a virtual learning environment over one year. Assessed assignments between and after the residential weeks provide opportunities for individual reflective learning for each delegate through applying concepts and the lessons of case studies to their experience, current challenges and expected responsibilities. This successful partnership between a major global company and a university rich in research and teaching required a significant dedication of intellectual and leadership effort by all concerned. The rewards for both parties and most importantly for the engineers themselves are extensive.  相似文献   
116.
117.
Data on perinatal and early childhood somatic and psychological risk factors of a random sample of children were gathered in early to middle childhood and employed to examine the long-term risk of emotional and behavioral problems of late childhood and adolescence. 3 issues were addressed: First, can syndromic specificity of such effects be identified on scaled and diagnostic measures of syndromes? Second, are these effects attributable to excess risk of low-income children for both perinatal and later childhood problems? Third, are the intervening mechanisms identifiable as intellectual impairment, vulnerability to poor health, poor maternal caretaking, maternal rejection, or maternal stress associated with marital problems? Findings indicated that elevated risk was present for all syndromes, both at the scale level and at the diagnostic level. None of the examined intervening mechanisms fully accounted for the effects of early risks.  相似文献   
118.
119.
学术殖民主义在行动:美国认证他国大学   总被引:5,自引:3,他引:5  
美国认证是针对美国高等教育的现实而设计的,它反映了美国学术系统的历史、规范以及价值观。作为一个学术超级大国,美国有义务不在全球滥用其学术强势。不存在任何形式的世界认证警察。  相似文献   
120.
Acknowledging the affective in higher education   总被引:1,自引:0,他引:1  
This article argues that we need richer conceptions of students as affective and embodied selves and a clearer theorisation of the role of emotion in educational encounters. These areas are currently under‐researched and under‐theorised in higher education. The first part of the article explores the literature on emotion. The second reports on a case study which aimed to map students' emotional journeys over their first year at university. These data highlight the importance of relationships, students' changing emotions over the year, their perceptions of their academic studies and understandings of life at university. The article concludes that it is important to understand the affective dimension in pedagogic encounters and the lifeworld of students, and that it is possible to do so without a collapse into therapeutic discourses.  相似文献   
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