...1/ ENERGY BANDS IN SOLIDS In this chapter we begin with a review of the basic atomic properties of matter leading to discrete electronic energy levels in atoms. We find that these energy levels are spread into energy bands in a crystal. This band structure allows us to distinguish between an insulator, a semiconductor, and a metal. 1-1 CHARGED PARTICLES The charge, or quantity, of negative electricity and the mass of the electron have been found to be 1.60 X 10- 19 C (coulomb) and 9.11 X 10- 31 kg, respectively. The values of many important physical constants are given in Appendix A, and a list of conversion factors and prefixes is given in Appendix B. Some idea of the number of electrons per second that represents current of the usual order of magnitude is readily possible. F'or example, since the charge per electron is 1.60 X 10- 19 C, the number of electrons per coulomb is the reciprocal of this nutnber, or approximately, 6 X 10 18 Further, since a current of 1 A (ampere) is the flow of 1 Cis, then a current of only 1 pA (1 picoampere, or 10- 12 A) represents the motion of approximately 6 million electrons per second. Yet a current of 1 pA is so small that considerable difficulty is experienced in attempting to measure it. The charge of a positive ion is an integral multiple of the charge of the electron, although it is of opposite sign. For the case of singly ionized particles, the charge is equal to that of the electron. For the case of doubly ionized particles...
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...Lobschat, L., Zinnbauer, M. A., Pallas, F., & Joachimsthaler, E. (2013). Why Social Currency Becomes a Key Driver of a Firm's Brand Equity – Insights from the Automotive Industry. Long Range Planning, 46(PLS applications in strategic management: Partial Least Squares modeling in strategy research), 125-148. doi:10.1016/j.lrp.2012.11.004 Introduction In the past decade, managers have endeavored to build brands by creating a strong identity and conveying this identity through consistently managing relevant touch points with customers (e.g., Aaker and Joachimsthaler, 2000; Keller and Lehmann, 2003). To this end, managers are striving to better understand consumer behavior and positively influence consumers' brand perceptions through marketing initiatives (e.g., Keller, 1993). However, the direction of influence on a brand's perception and image has become increasingly bilateral. Today, consumers are no longer simply “receivers” of company- and brand-related information. Instead, they operate as “senders” of this information, e.g., by giving brand recommendations, by expressing criticism, or by sharing information with others (Hennig-Thurau et al., 2010). For this reason, managers no longer have exclusive control over information circulating about a company or brand. Consumers therefore play an important role in forming a company's or brand's perception and value in the marketplace (Keller, 2007). Exchange of information about companies and brands between consumers is not...
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...Acknowledgments ix Acknowledgments This book owes a great deal to the mental energy of several generations of scholars. As an undergraduate at the University of Cape Town, Francis Wilson made me aware of the importance of migrant labour and Robin Hallett inspired me, and a generation of students, to study the African past. At the School of Oriental and African Studies in London I was fortunate enough to have David Birmingham as a thesis supervisor. I hope that some of his knowledge and understanding of Lusophone Africa has found its way into this book. I owe an equal debt to Shula Marks who, over the years, has provided me with criticism and inspiration. In the United States I learnt a great deal from ]eanne Penvenne, Marcia Wright and, especially, Leroy Vail. In Switzerland I benefitted from the friendship and assistance of Laurent Monier of the IUED in Geneva, Francois Iecquier of the University of Lausanne and Mariette Ouwerhand of the dépurtement évangélrlyue (the former Swiss Mission). In South Africa, Patricia Davison of the South African Museum introduced me to material culture and made me aware of the richness of difference; the late Monica Wilson taught me the fundamentals of anthropology and Andrew Spiegel and Robert Thornton struggled to keep me abreast of changes in the discipline; Sue Newton-King and Nigel Penn brought shafts of light from the eighteenthcentury to bear on early industrialism. Charles van Onselen laid a major part of the intellectual foundations on...
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