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Books > Professional & Technical > Industrial chemistry & manufacturing technologies > Metals technology / metallurgy
The book describes the valorization of biomass-derived compounds
over gold catalysts. Since biomass is a rich renewable feedstock
for diverse platform molecules, including those currently derived
from petroleum, the interest in various transformation routes has
become intense. Catalytic conversion of biomass is one of the main
approaches to improving the economic viability of biorefineries. In
addition, Gold catalysts were found to have outstanding activity
and selectivity in many key reactions. This book collects
information about transformations of the most promising and
important compounds derived from cellulose, hemicelluloses, and
woody biomass extractives. Since gold catalysts possess high
stability under oxidative conditions, selective oxidation reactions
were discussed more thoroughly than other critical reactions such
as partial hydrogenation, acetalization, and isomerization. The
influence of reaction conditions, the role of the catalyst, and the
advantages and disadvantages of using gold are presented for all of
the reactions mentioned above. This book provides an overview of
the recent research results focusing on application of gold
catalysts for synthesis of valuable chemicals using renewable
feedstocks.
The first International Conference on Thermoelectric Properties of
Metallic Conductors was held at Michigan State University on August
10-12, 1977. The conference was sponsored and supported by the
National Science Foundation, the Office of Naval Research and the
Ford Motor Company. Although the topic may appear, at first glance,
rather narrow and of limited interest, it impacts significantly on
numerous fields of research, in each instance providing a unique
and fru- ful technique for securing important data that is
frequently difficult to obtain by other means. Thus, though
thermoelectricity is the thread that binds these pages together,
the papers constitute a patchwork quilt that includes critical
phenomena, superconductivity, many-body theory, quasi
one-dimensional systems, liquid metals, to mention only a few. This
volume contains the 12 invited and 31 contributed papers, arranged
in the order in which they were presented, as well as much of the
frequently spirited and always illuminating discussion that
followed these papers. Regrettably, not all of the discussion is
included. Difficulties with the recording system during the first
session (Wednesday morning) did not become apparent before the end
of that session, and, consequently, none of the discussion--some of
it fairly heated--appears in the proceedings; other remarks were
lost to posterity through occasional malfunctioning of the record
ing facilities and/or failure of speakers to come near a
microphone."
The rare earths have a unique place among the elements. Although
very much alike chemically and in most phy ical properties they
each have very different and striking magnetic properties. The
reason, of course, lies in their 4f electrons which determine the
magnetic properties but have little effect on other chemical and
physical behaviour. Although they are not rare, some indeed are
among the more common heavy elements in the earth's crust, the
difficulty of separation has meant that their intricate magnetic
properties have only recently been unravelled. Now, however, the
general pattern of their magnetism is well charted and the
underlying theory is well understood. Both are thoroughly
summarised in this book. It provides an excellent example of the
kind of extensive synthesis which is possible with modem solid
state physics. it represents only a high plateau in the ascent to
complete understanding. But It will become clear to the reader that
while the overall position is satisfactory there are many details
still to be elucidated experimentally and much to be done
theoretically before all the underlying forces are identified and
estimated from a priori calculations. It is hoped that the book
will provide a useful stimulus in this direction. It should also be
of use to those who are interested in related disciplines, for
example the rare earth compounds, or the transition metals. In
addition rare earths promise to be important technologically as
alloy constituents.
Industrial advances frequently depend on the development of new,
special-purpose ma terials possessing specific magnetic,
electrical, optical, strength, friction, antifriction, and other
properties. Metal alloys produced by the conventional technique of
metallurgical reduc tion often do not meet these new requirements.
Powder metallurgy, therefore, is of consider able importance in
solving many problems of present-day materials science. Its
production techniques-solid-phase and liquid-phase sintering,
impregnation, hot pressing - make it pos, ... sible to obtain
materials from metallic components which are immiscible in the
liquid state and also materials in which metals are combined with
nonmetallic components such as refract ory compounds- oxides,
carbides, nitrides, borides, sUicides, sulfides, etc. The
properties of sintered parts depend essentially on the processes
occurring during their formation. One of the most promising methods
of producing sintered materials of high density with the best
combination of various properties is liquid-phase sintering. In
recent years, many publications have appeared concerning processes
of sintering specific combinations of com ponents, the theoretical
basis of liquid-phase sintering, and the laws governing this
process. The present work examines liquid-phase sintering processes
and the action of capillary forces in models of dispersed
solid-liquid systems, and also gives data from theoretical and
experi mental studies of liquid-phase sintering in various metal
and metal-ceramic systems. Some theoretical generalizations on the
principles of sintering processes are presented, and the driv ing
forces of sintering and the effect of different conditions on
liquid-phase sintering processes are considered."
Mechanical alloying (or mechanical milling) was invented in the
1970's as a method to develop dispersion-strengthened high
temperature alloys with unique properties. With the discovery of
formation of amorphous alloys using this technique, it has received
new research interest in developing different material systems.
Potential applications of this technique have been demonstrated in
different areas of materials research. This book is intended as an
introduction to mechanical alloying technique used in difference
areas. This book contains basic information on the preparation of
materials using the mechanical alloying technique. It is useful not
only to undergraduate and post-graduate students, but also to
scientists and engineers who wish to gain some understanding on the
basic process and mechanisms of the process. The book begins with a
brief introduction to provide a historical background understanding
to the development of the mechanical alloying process. The
experimental set-up in the alloying process is important. Currently
there are different types of ball mills available. Some of them are
specially designed for mechanical alloying process. Since the
resultant materials are milling intensity and milling temperature
dependent, ball mills should be carefully selected in order to
obtain the desired materials and structures. This is discussed in
chapter 2. The actual mechanical alloying process is being
considered in Chapter 3. As it is essential to understand the use
of processing control agents, the physical properties of some
commonly used processing control agents are listed.
Electrometallurgy is a broad field but it is not a new one. It was
the great Faraday in the 1830s who discovered laws covering the
electrodeposition of metals and its relation to the current passed
and equivalent weight of the metal undergoing depo- tion. Since
that time, applications and developments of his discoveries have
spread to many areas of technology. Electrowinning is the most well
known, partly because it embraces the process by which aluminum is
extracted from its ores. In electrorefining, the impure metal is
made into anode and the pure metal dissolved therefrom is deposited
on a cathode. Electroplating is exemplified by its use in the
manufacture of car bumpers. Finally, in electroreforming, objects
may be metallized, often with a very thin layer of the coating
desired. The numerous technologies vary greatly in the degree to
which they are intell- tualized. Until the work of Popov et al. ,
electrometallurgy has been regarded as largely empirical, an
activity in which there was much art and little science. This will
all change with the publication of this book. Several aspects of
the background of its senior author, Konstantin Popov, make him
uniquely suited to the job of intellectual- ing electrometallurgy.
First, he had as his mentor the great surely the leading
electrochemist in Eastern Europe since the death of Frumkin.
Second, he has had ample experience with the leading
electrochemical engineer in America, Ralph White.
The increasing use of powder metallurgy techniques to make an
almost infinite variety of materials and products places greater
emphasis on utilization of sophisticated experimental techniques.
Usually research and development efforts initiate the use of newly
developed equipment and analytical procedures. Indeed, the contents
of this book are strongly linked to research endeavors, in both the
academic and industrials worlds. However, this volume can serve a
much needed function in industrial applied powder metallurgy.
Although many research ers will find the contents of great value,
the technical personnel more involved with production, quality
control, customer services and product design now have at their
dispo sal a means to learn about the potential uses of several very
important techniques. With today's "knowledge explosion" the
present set of papers greatly facilitates the comprehension and
adoption of new procedures. If powder metallurgy is to continue its
rapid rate of growth in virtually all segments of industry, then
the transition of modern equipment and procedures from tools of
research and development laboratories to everyday plant operations
and applications must be hastened. The editors hope that this
volume aids in this process, as well as assisting students and
researchers by providing a ready source of up-to-date useful
information.
High-technology and environmental applications of the rare-earth
elements (REE) have grown dramatically in diversity and importance
over the past four decades. This book provides a scientific
understanding of rare earth properties and uses, present and
future. It also points the way to efficient recycle of the rare
earths in end-of-use products and efficient use of rare earths in
new products. Scientists and students will appreciate the book's
approach to the availability, structure and properties of rare
earths and how they have led to myriad critical uses, present and
future. Experts should buy this book to get an integrated picture
of production and use (present and future) of rare earths and the
science behind this picture. This book will prove valuable
to.non-scientists as well in order to get an integrated picture of
production and use of rare earths in the 21st Century, and the
science behind this picture.
Stereology is the science that relates three-dimensional structure
to the two-dimensional images that can be measured. The most common
field of application is in microscopy, both of man-made materials
(metals, ceramics, composites, etc.) and of biological tissue
samples. This book covers the applications and terminology of both
fields. Recent emphasis in stereology is concerned with sampling
strategies to avoid bias due to directionality and non-uniformity,
and these methods are fully covered. So are the classic techniques
that measure size distributions, surface curvature, etc., which are
widely useful but not discussed in other recent texts. Finally,
most stereology is taught as manual procedures using counting and
grids, but this text also covers the use of modern desktop
computers for image analysis and processing to obtain and interpret
the stereological data.
This monograph describes mathematical models that enable
prediction of phase compositions for various technological
processes, as developed on the base of a complex physico-chemical
analysis of reaction. It studies thermodynamics and kinetics of
specific stages of complex pyrometallurgical processes involving
boron, carbon, sulfur, tungsten, phosphorus, and many more, as well
as their exposure to all sorts of factors.
First and foremost, this enables to optimize processes and
technologies at the stage of design, while traditional empirical
means of development of new technologies are basically incapable of
providing an optimal solution. Simulation results of metals and
alloys production, welding and coating technologies allow obtaining
materials with pre-given composition, structure and properties in a
cost-saving and conscious manner. Moreover, a so-called "inverse
problem," i.e., selecting source materials which would ensure the
required results, cannot be solved by any other means.
THE PHYSICAL BASIS FOR HETEROGENEOUS CATALYSIS is the proceedings
of the ninth Battelle Colloquium in the Materials Sciences, held in
Gstaad, Switzerland, September 2-6, 1974. It took as its theme the
application of modern theoretical and experimental surface physics
to heterogeneous catalysis. Progress in the field by classical
chemical methods seemed to have slowed down, at a time when the
need for better catalysts was particularly great. The Organizing
Committee thought it might be possible to accelerate progress by
the application of the powerful techniques evolved in recent years
for studying atomically clean surfaces. However, the translation of
ideas derived from clean single crystal surfaces with well
characterized chemisorbed layers to real catalysts with high ratios
of surface to mass on which reactions were taking place and
requiring transport of mass and energy is a giant step, raising
many questions and requiring thorough discussion by surface
physicists on the one hand and catalytic chemists on the other. The
1974 Battelle Colloquium provided a forum for this exchange. As its
usual custom, the Colloquium started the first day of introduc tory
lectures by three distinguished scientists who have contributed
impor tantly over many years to this field."
Composite Materials in Aerospace Design is one of six titles in a
coherent and definitive series dedicated to advanced composite
materials research, development and usage in the former Soviet
Union. Much of the information presented has been classified until
recently. Thus each volume provides a unique insight into hitherto
unknown research and development data. This volume deals with the
design philosophy and methodology used to produce primary and
secondary load bearing composite structures with high life
expectancies. The underlying theme is of extensive advanced
composites research and development programs in aircraft and
spacecraft applications, including the space orbital ship `BURAN'.
The applicability of much of this work to other market sectors,
such as automotive, shipbuilding and sporting goods is also
examined in some detail. The text starts by describing typical
structures for which composites may be used in this area and some
of the basic requirements from the materials being used. Design of
components with composite materials is then discussed, with
specific reference to case studies. This is followed by discussion
and results from evaluation of finished structures and components,
methods of joining with conventional materials and finally,
non-destructive testing methods and forecasting of the performance
of the composite materials and the structures which they form.
Composite Materials in Aerospace Design will be of interest to
anyone researching or developing in composite materials science and
technology, as well as design and aerospace engineers, both in
industry and universities.
Silicon Carbide Microsystems for Harsh Environments reviews
state-of-the-art Silicon Carbide (SiC) technologies that, when
combined, create microsystems capable of surviving in harsh
environments, technological readiness of the system components, key
issues when integrating these components into systems, and other
hurdles in harsh environment operation. The authors use the SiC
technology platform suite the model platform for developing harsh
environment microsystems and then detail the current status of the
specific individual technologies (electronics, MEMS, packaging).
Additionally, methods towards system level integration of
components and key challenges are evaluated and discussed based on
the current state of SiC materials processing and device
technology. Issues such as temperature mismatch, process
compatibility and temperature stability of individual components
and how these issues manifest when building the system receive
thorough investigation. The material covered not only reviews the
state-of-the-art MEMS devices, provides a framework for the joining
of electronics and MEMS along with packaging into usable
harsh-environment-ready sensor modules.
This book deals with a novel and practical advanced method for
control of tandem cold metal rolling processes based on the
emerging state-dependent Riccati equation technique. After a short
history of tandem cold rolling, various types of cold rolling
processes are described. A basic mathematical model of the process
is discussed, and the diverse conventional control methods are
compared. A detailed treatment of the theoretical and practical
aspects of the state-dependent algebraic Riccati equation technique
is given, with specific details of the new procedure described and
results of simulations performed to verify the control model and
overall system performance with the new controller coupled to the
process model included. These results and data derived from actual
operating mills are compared showing the improvements in
performance using the new method. Material is included which shows
how the new technique can be extended to the control of a broad
range of large-scale complex nonlinear processes.
In the preliminary stage of designing new structural hardware that
must perform a given mission in a fluctuating load environment,
there are several factors the designers should consider. Trade
studies for different design configurations should be performed
and, based on strength and weight considerations, among others, an
optimum configuration selected. The selected design must be able to
withstand the environment in question without failure. Therefore, a
comprehen sive structural analysis that consists of static,
dynamic, fatigue, and fracture is necessary to ensure the integrity
of the structure. During the past few decades, fracture mechanics
has become a necessary discipline for the solution of many
structural problems. These problems include the prevention of
failures resulting from preexisting cracks in the parent material,
welds or that develop under cyclic loading environment during the
life of the structure. The importance of fatigue and fracture in
nuclear, pressure vessel, aircraft, and aerospace structural
hardware cannot be overemphasized where safety is of utmost
concern. This book is written for the designer and strength
analyst, as well as for the material and process engineer who is
concerned with the integrity of the structural hardware under
load-varying environments in which fatigue and frac ture must be
given special attention. The book is a result of years of both
acade mic and industrial experiences that the principal author and
co-authors have accumulated through their work with aircraft and
aerospace structures."
In an attempt to meet the demand for new ultra-high strength
materials, the processing of novel material configurations with
unique microstructure is being explored in systems which are
further and further from equilibrium. One such class of emerging
materials is the so-called nanophased or nanostructured materials.
This class of materials includes metals and alloys, ceramics, and
polymers characterized by controlled ultra-fine microstructural
features in the form oflayered, fibrous, or phase and grain
distribution. While it is clear that these materials are in an
early stage of development, there is now a sufficient body of
literature to fuel discussion of how the mechanical properties and
deformation behavior can be controlled through control of the
microstructure. This NATO-Advanced Study Institute was convened in
order to assess our current state of knowledge in the field of
mechanical properties and deformation behavior in materials with
ultra fine microstructure, to identify opportunities and needs for
further research, and to identify the potential for technological
applications. The Institute was the first international scientific
meeting devoted to a discussion on the mechanical properties and
deformation behavior of materials having grain sizes down to a few
nanometers. Included in these discussions were the topics of
superplasticity, tribology, and the supermodulus effect. Lectures
were also presented which covered a variety of other themes
including synthesis, characterization, thermodynamic stability, and
general physical properties."
This book is intended to give an introduction and a comprehensive
overview concerning the main areas of surface magnetism with
special emphasis on rare earth metals. Investigations in this ?eld
require experimental techniques which are sensitive to the topmost
layers on the one hand and simultaneously to magnetic properties on
the other hand. Using additionally tools with a high lateral
resolution the visualization of magnetic domains becomes possible.
Theunderstandingofmagneticandelectronicbehaviorrequirestheknowledgeof
the structure on a microscopic scale. Due to this important
relationship the dep- dence of electronic on structural properties
is the ?rst topic. This contains inves- gations not only on rare
earth metals but additionally on 3d ferromagnetic systems. It is
important to keep in mind that the chemical behavior of a surface
det- mines the surface electronic properties. Thus, variations,
e.g. due to adsorbate atoms, have a signi?cant in?uence. This
aspect will be focused on as the next topic with the description of
selected substrate layers which were exposed to different types of
gaseous molecules. Investigations on the surface magnetism of
itinerant ferromagnetic materials, including the in?uence of
adsorbates on surface magnetic properties, and magnets with
localized moments is the ?nal and main topic of this volume. It
will end with the realization of laterally resolved spin polarized
vacuum tunneling which enables to image magnetic domains on the
nanometer scale. Acknowledgements This work summarizes my research
on the above-mentioned topics performed at the Universities of
Bielefeld, Mainz, Hamburg, and Dusseldorf."
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