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This textbook bridges the gap between basic literature on the
physics of solar cells and highly specialized books about
photovoltaic solar energy conversion. It is intended to give
students with a background in engineering, materials science,
chemistry or physics a comprehensive introduction to materials
concepts for solar cells. To this end, general principles of solar
cells and materials demands are explained in the first part of this
book. The second part is devoted to the four classes of materials
concepts for solar cells: solar cells based on crystals of silicon,
epitaxial layer systems of III-V semiconductors, thin-film
absorbers on foreign substrates, and nano-composite absorbers.
A modern challenge is for solar cell materials to enable the
highest solar energy conversion efficiencies, at costs as low as
possible, and at an energy balance as sustainable as necessary in
the future. This textbook explains the principles, concepts and
materials used in solar cells. It combines basic knowledge about
solar cells and the demanded criteria for the materials with a
comprehensive introduction into each of the four classes of
materials for solar cells, i.e. solar cells based on crystalline
silicon, epitaxial layer systems of III-V semiconductors, thin-film
absorbers on foreign substrates, and nano-composite absorbers. In
this sense, it bridges a gap between basic literature on the
physics of solar cells and books specialized on certain types of
solar cells.The last five years had several breakthroughs in
photovoltaics and in the research on solar cells and solar cell
materials. We consider them in this second edition. For example,
the high potential of crystalline silicon with charge-selective
hetero-junctions and alkaline treatments of thin-film absorbers,
based on chalcopyrite, enabled new records. Research activities
were boosted by the class of hybrid organic-inorganic metal halide
perovskites, a promising newcomer in the field.This is essential
reading for students interested in solar cells and materials for
solar cells. It encourages students to solve tasks at the end of
each chapter. It has been well applied for postgraduate students
with background in materials science, engineering, chemistry or
physics.
This textbook bridges the gap between basic literature on the
physics of solar cells and highly specialized books about
photovoltaic solar energy conversion. It is intended to give
students with a background in engineering, materials science,
chemistry or physics a comprehensive introduction to materials
concepts for solar cells. To this end, general principles of solar
cells and materials demands are explained in the first part of this
book. The second part is devoted to the four classes of materials
concepts for solar cells: solar cells based on crystals of silicon,
epitaxial layer systems of III-V semiconductors, thin-film
absorbers on foreign substrates, and nano-composite absorbers.
Surface photovoltage (SPV) techniques provide information about
photoactive materials with respect to charge separation in space.
This book aims to share experience in measuring and analyzing SPV
signals and addresses researchers and developers interested in
learning more about and in applying SPV methods. For this purpose,
basics about processes in photoactive materials and principles of
SPV measurements are combined with examples from research and
development over the last two decades.SPV measurements with Kelvin
probes, fixed capacitors, electron beams and photoelectrons are
explained. Details are given for continuous, modulated and
transient SPV spectroscopy. Simulation principles of SPV signals by
random walks are introduced and applied for small systems.
Application examples are selected for the characterization of
silicon surfaces, gallium arsenide layers, electronic states in
colloidal quantum dots, transport phenomena in metal oxides and
local charge separation across photocatalytic active crystallites.
Lithium-cesium-tantalum (LCT) pegmatites are important resources
for rare metals. For Cs, only the LCT pegmatites with the zeolite
group mineral pollucite at Bikita (Zimbabwe Craton) and Tanco
(Superior Province Craton) are of commercial importance. Common
characteristics of world-class LCT pegmatite deposits include their
Meso- to Neoarchean age and geological setting within greenstone
belt lithologies on Archean Cratons. This study presents the first
coherent and comparative scientific investigation of five major LCT
pegmatite systems from the Yilgarn, Pilbara and Zimbabwe Craton.
For the evaluation of their Cs potential and of the genetic
concepts of pollucite formation, the pegmatites from Wodgina,
Londonderry, Mount Deans and Cattlin Creek were compared to the
Bikita pollucite mineralization. The integration of the new
data (e.g., geochronological and radiogenic isotope data) into the
complex geological framework: 1) enhances our knowledge of the
formation of LCT pegmatite systems, and 2) will contribute to the
further exploration of additional world-class LCT pegmatite
deposits, which 3) may host massive pollucite
mineralisations.Â
This wide-ranging book introduces information as a key concept not
only in physics, from quantum mechanics to thermodynamics, but also
in the neighboring sciences and in the humanities. The central part
analyzes dynamical processes as manifestations of information flows
between microscopic and macroscopic scales and between systems and
their environment. Quantum mechanics is interpreted as a
reconstruction of mechanics based on fundamental limitations of
information processing on the smallest scales. These become
particularly manifest in quantum chaos and in quantum computing.
Covering subjects such as causality, prediction, undecidability,
chaos, and quantum randomness, the book also provides an
information-theoretical view of predictability. More than 180
illustrations visualize the concepts and arguments. The book takes
inspiration from the author's graduate-level topical lecture but is
also well suited for undergraduate studies and is a valuable
resource for researchers and professionals.
A modern challenge is for solar cell materials to enable the
highest solar energy conversion efficiencies, at costs as low as
possible, and at an energy balance as sustainable as necessary in
the future. This textbook explains the principles, concepts and
materials used in solar cells. It combines basic knowledge about
solar cells and the demanded criteria for the materials with a
comprehensive introduction into each of the four classes of
materials for solar cells, i.e. solar cells based on crystalline
silicon, epitaxial layer systems of III-V semiconductors, thin-film
absorbers on foreign substrates, and nano-composite absorbers. In
this sense, it bridges a gap between basic literature on the
physics of solar cells and books specialized on certain types of
solar cells.The last five years had several breakthroughs in
photovoltaics and in the research on solar cells and solar cell
materials. We consider them in this second edition. For example,
the high potential of crystalline silicon with charge-selective
hetero-junctions and alkaline treatments of thin-film absorbers,
based on chalcopyrite, enabled new records. Research activities
were boosted by the class of hybrid organic-inorganic metal halide
perovskites, a promising newcomer in the field.This is essential
reading for students interested in solar cells and materials for
solar cells. It encourages students to solve tasks at the end of
each chapter. It has been well applied for postgraduate students
with background in materials science, engineering, chemistry or
physics.
Masterarbeit aus dem Jahr 2011 im Fachbereich BWL - Personal und
Organisation, Note: 1,0, Leuphana Universitat Luneburg,
Veranstaltung: Performane Management, Psychologie, BWL, Sprache:
Deutsch, Anmerkungen: Empirische Studie mit uber 200 Teilnehmern.
Theorie u.a. beruhend auf Deci/Ryan sowie Hackman/Oldham. Rund 200
Seiten. Inkl. Fragebogen im Anhang., Abstract: Die vorliegende
Arbeit nimmt die Forschung um die altersbedingte Veranderung von
Motiven auf und untersucht vier Motive, die eng mit intrinsischer
Motivation verbunden sind: Selbstentfaltung, Autonomie, Affiliation
und Generativitat. Die ersten drei Motive hangen stark mit den von
Deci und Ryan definierten Grundbedurfnissen ihrer
Selbstbestimmungstheorie zusammen (Deci & Ryan, 1993 und 2000).
Die Forschung und Theorien zum Generativitatsmotiv, insbesondere im
Arbeitskontext, sind deutlich junger und seltener (u. a. Grube,
2009, Zacher et al., 2011, Kooij & van de Voorde, 2011). Die
Studie bestatigt Unterschiede zwischen jungeren und alteren
Mitarbeitern hinsichtlich des Autonomie- und des
Generativitatsmotivs. Allerdings wird deutlich, dass neben dem
Alter auch die Dauer der Betriebszugehorigkeit, die eng mit dem
Alter zusammenhangt, und die Funktion des Beschaftigten fur die
Auspragung der Motive eine Rolle spielen. Hinsichtlich der Motive
nach Selbstentfaltung und Affiliation zeigt die Arbeit, dass
jungere und altere Mitarbeiter ahnlich hohe Auspragungen haben.
Alle bekannten empirischen Studien zu altersbedingten Veranderungen
rund um das Thema Arbeitsmotivation beschaftigen sich bisher
entweder mit den Motiven und der Motivation oder den
Arbeitsbedingungen und der Motivation. Diese Arbeit fuhrt nun alle
drei Elemente zusammen. Neben der intrinsischen Motivation und den
Motiven als eine Ursache fur Motivation werden auch die zur
Befriedigung der Motive notwendigen Arbeitsbedingungen untersucht.
Die vorliegende Arbeit untersucht die Wahrnehmung von vier der funf
von Hackman und Oldham als Kernfaktoren
Die demografische Entwicklung in Deutschland hat einen erheblichen
Einfluss auf die Altersstruktur in Unternehmen. In vielen Regionen
und Branchen sinkt das Angebot an jungen Arbeitskr ften.
Gleichzeitig f hren die Abschaffung der staatlichen Unterst tzung
der Fr hverrentung und die Anhebung der Regelaltersrente auf 67
Jahre dazu, dass immer mehr ltere Menschen arbeiten. Das
Durchschnittsalter in den Unternehmen steigt; die Notwendigkeit der
(Weiter-)Besch ftigung erfahrener Mitarbeiter ebenfalls. Schon seit
mehreren Jahrzehnten besch ftigt sich die Forschung mit dem Erhalt
der k rperlichen und geistigen Leistungsf higkeit lterer Besch
ftigter. Seit Anfang der 2000er Jahre r ckte auch die
Arbeitsmotivation als eine zu ber cksichtigende Komponente verst
rkt ins Blickfeld. Mitarbeiter nur f r eine m glichste lange Besch
ftigung zu bef higen, wurde nicht mehr als ausreichend betrachtet.
Es galt gleichzeitig, ihren Leistungswillen zu erhalten. Diese
Studie untersucht mehrere Komponenten der Arbeitsmotivation und
deren Zusammenhang zum Alter. Neben der Frage, ob sich j ngere und
ltere Mitarbeiter hinsichtlich ihrer intrinsischen
Arbeitsmotivation grunds tzlich unterscheiden, stehen zwei Aspekte
im Fokus. Zum einen wurde untersucht, ob ltere Mitarbeiter
spezifische Arbeits- und Organisationsfaktoren f r ihre Motivation
ben tigen. Daf r wurde berpr ft, ob sich j ngere und ltere
Mitarbeiter in ihren arbeitsbezogenen Motiven unterscheiden. Zum
anderen sollte herausgefunden werden, ob es altersabh ngige
Unterschiede im Vorhandensein bzw. der Wahrnehmung bestimmter
Arbeitsbedingungen gibt. Die untersuchten Motive werden gr tenteils
auf die Selbstbestimmungstheorie von Deci und Ryan zur ckgef hrt.
Die Arbeitsbedingungen auf das Modell der Jobcharakteristika von
Hackman und Oldham. Daneben spielen einige neuere Forschungen zur
Generativit t und der M glichkeit zur Weitergabe von Wissen eine
Rolle. Die Untersuchung macht altersbedingte Unterschiede sowohl in
der Wahrnehm
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