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Books > Science & Mathematics > Physics > Applied physics & special topics
This book addresses the mechanism of enrichment of heavy elements
in galaxies, a long standing problem in astronomy. It mainly
focuses on explaining the origin of heavy elements by performing
state-of-the-art, high-resolution hydrodynamic simulations of dwarf
galaxies. In this book, the author successfully develops a model of
galactic chemodynamical evolution by means of which the neutron
star mergers can be used to explain the observed abundance pattern
of the heavy elements synthesized by the rapid neutron capture
process, such as europium, gold, and uranium in the Local Group
dwarf galaxies. The book argues that heavy elements are significant
indicators of the evolutionary history of the early galaxies, and
presents theoretical findings that open new avenues to
understanding the formation and evolution of galaxies based on the
abundance of heavy elements in metal-poor stars.
Prior to the 1920s it was generally thought, with a few exceptions,
that our galaxy, the Milky Way, was the entire universe. Based on
the work of Henrietta Leavitt with Cepheid variables, astronomer
Edwin Hubble was able to determine that others had to lie outside
our own. This books looks at 60 of those that possess some unusual
qualities that make them of particular interest, from supermassive
black holes and colliding galaxies to powerful radio sources.
This volume explores how ionic liquids are used in different areas
of biotechnology. It also provides insights on the interaction of
ionic liquids with biomolecules and biomaterials. Ionic liquids
have become essential players in the fields of synthesis,
catalysis, extraction and electrochemistry, and their unique
properties have opened a wide range of applications in
biotechnology. Readers will discover diverse examples of the
application of ionic liquids as solvents for biomaterials
extraction and pretreatment, in enzymatic and whole cell catalysed
reaction, and as activation agents for biocatalysis. Particular
attention is given to the biologically functionalized ionic liquids
employed in medical and pharmaceutical applications. Although ionic
liquids are considered "green solvents", the contributing authors
will also explore their environmental impact when applied to
biotechnology. Chemical, biological and medical scientists
interested in ionic liquids and biotechnology will find this work
instructive and informative.
In the field of particle and astrophysics one of the major
unresolved problems is to understand the nature and properties of
dark matter, which constitutes almost 80% of the matter content of
the universe. This book gives a pedagogical introduction to the
field of dark matter in general, and in particular to the model
building perspective. This book focuses on teaching the basic tools
for model building of dark matter, and it aims to motivate the
reader to propose a new dark matter model.
This thesis provides new insights into the seemingly anomalous
ubiquity of lithium-rich red giant stars. The theory of stellar
evolution, one of the most successful models of modern
astrophysics, predicts that red giant stars should display
negligible levels of lithium (Li) on their surfaces. However,
Li-rich giants, defined as those showing more than three times the
Li content of the Sun, are found everywhere astronomers look in
apparent defiance of established theory. The author addresses this
problem, analyzing the different possible explanations for such an
anomaly, which include interaction with a binary companion, the
production of Li in the interior of the star with its subsequent
transport to stellar exteriors, and the stellar interaction with
planets. The author focuses on this last possibility, where the Li
enrichment may be due to the ingestion of planets or brown dwarfs
as the stars in question grew in size while becoming giants. She
shows that this process is indeed able to explain an important
fraction of giants with Li levels above the three times solar
threshold, but that some other mechanism is needed to explain the
remaining fraction. While this is an important discovery in its own
right, the result that makes this thesis groundbreaking is its
demonstration that the threshold between Li-normal and Li-rich is
mass dependent rather than a fixed proportion of the Sun's content.
This corrects a fundamental misapprehension of the phenomenon and
opens up a new framework in which to understand and solve the
problem. Finally, the author presents interesting observational
applications and samples with which to test this new approach to
the problem of Li enrichment in giants.
This thesis describes the design, development, characterisation and
clinical translation of three novel devices for optical endoscopic
imaging. Over the past decade, rapid innovation in optics and
photonics has led to the availability of low-cost and
high-performance optical technologies that can be exploited for
biomedical applications, but relatively few have been translated
into clinic. The work presented outlines for the first time, a
comprehensive analysis of the common barriers and unique challenges
associated with the translation of optical imaging techniques. To
assist developers streamline translation of optical imaging devices
in future, a roadmap to clinical translation is outlined, and key
translational characteristics are defined. Guided by these,
subsequent development of endoscopic devices resulted in
preparation and approval of endoscopes for first in human trials in
the oesophagus, for early detection of cancer, and in the brain,
for delineation of tumour during surgical resection. The thesis
culminates in the presentation of results from the first in human
use of a compact multispectral endoscope for imaging endogenous
tissue contrast in the oesophagus. With continuation of the work as
outlined at the end of this thesis, the novel techniques described
have the potential to improve the standard of care in their
respective indications.
This book recounts the developments of fundamental electrodynamics from Ampère's investigation of the forces between electric currents to Einstein's introduction of a new doctrine of space and time. Thorough accounts are given of crucial episodes such as Faraday's redefinition of charge and current, the genesis of Maxwell's field equations, and Hertz' experiments on fast electric oscillations. Darrigol provides a vivid picture of the intellectual and instrumental variety of nineteenth century physics, emphasising the diverse, evolving practices of electrodynamics, and the interactions between the corresponding scientific traditions. This richly documented, clearly written, and abundantly illustrated history should appeal to students and scholars of physics, and also to those interested in the history and philosophy of science.
This book provides a unified treatment of the characteristics of
telescopes of all types, both those whose performance is set by
geometrical aberrations and the effect of the atmosphere, and those
diffraction-limited telescopes designed for observations from above
the atmosphere. The emphasis throughout is on basic principles,
such as Fermat's principle, and their application to optical
systems specifically designed to image distant celestial
sources.
The book also contains thorough discussions of the principles
underlying all spectroscopic instrumentation, with special emphasis
on grating instruments used with telescopes. An introduction to
adaptive optics provides the needed background for further inquiry
into this rapidly developing area.
* Geometrical aberration theory based on Fermat's
principle
* Diffraction theory and transfer function approach to near-perfect
telescopes
* Thorough discussion of 2-mirror telescopes, including
misalignments
* Basic principles of spectrometry; grating and echelle
instruments
* Schmidt and other catadioptric telescopes
* Principles of adaptive optics
* Over 220 figures and nearly 90 summary tables
The invention of the semiconductor laser along with silica glass
fiber has enabled an incredible revolution in global communication
infrastructure of direct benefit to all. Development of devices and
system concepts that exploit the same fundamental light-matter
interaction continues. Researchers and technologists are pursuing a
broad range of emerging applications, everything from automobile
collision avoidance to secure quantum key distribution. This book
sets out to summarize key aspects of semiconductor laser device
physics and principles of laser operation. It provides a convenient
reference and essential knowledge to be understood before exploring
more sophisticated device concepts. The contents serve as a
foundation for scientists and engineers, without the need to invest
in specialized detailed study. Supplementary material in the form
of MATLAB is available for numerically generated figures.
This monograph presents recent advances in neural network (NN)
approaches and applications to chemical reaction dynamics. Topics
covered include: (i) the development of ab initio potential-energy
surfaces (PES) for complex multichannel systems using modified
novelty sampling and feedforward NNs; (ii) methods for sampling the
configuration space of critical importance, such as trajectory and
novelty sampling methods and gradient fitting methods; (iii)
parametrization of interatomic potential functions using a genetic
algorithm accelerated with a NN; (iv) parametrization of analytic
interatomic potential functions using NNs; (v) self-starting
methods for obtaining analytic PES from ab inito electronic
structure calculations using direct dynamics; (vi) development of a
novel method, namely, combined function derivative approximation
(CFDA) for simultaneous fitting of a PES and its corresponding
force fields using feedforward neural networks; (vii) development
of generalized PES using many-body expansions, NNs, and moiety
energy approximations; (viii) NN methods for data analysis,
reaction probabilities, and statistical error reduction in chemical
reaction dynamics; (ix) accurate prediction of higher-level
electronic structure energies (e.g. MP4 or higher) for large
databases using NNs, lower-level (Hartree-Fock) energies, and small
subsets of the higher-energy database; and finally (x) illustrative
examples of NN applications to chemical reaction dynamics of
increasing complexity starting from simple near equilibrium
structures (vibrational state studies) to more complex
non-adiabatic reactions.
The monograph is prepared by an interdisciplinary group of
researchers working as a team for nearly two decades at Oklahoma
State University, Stillwater, OK with expertise in gas phase
reaction dynamics; neural networks; various aspects of MD and Monte
Carlo (MC) simulations of nanometric cutting, tribology, and
material properties at nanoscale; scaling laws from atomistic to
continuum; and neural networks applications to chemical reaction
dynamics. It is anticipated that this emerging field of NN in
chemical reaction dynamics will play an increasingly important role
in MD, MC, and quantum mechanical studies in the years to come.
Marine enzymes and specialized metabolism - Part B, Volume 605 in
the Methods in Enzymology series, highlights experimental methods
on diverse marine enzymes involved in the construction of bioactive
natural product molecules. Unique sections in this new release
include discussions on polysaccharide-degrading enzymes from marine
gastropods, radical SAM epimerases from sponge microbes, DMS/P
demethylase in bacteria, reconstitution of particulate methane
monooxygenase into membrane mimetics, the structure and function of
cyanobactin enzymes, marine cyanobacterial polyketide
beta-branching enzymology, marine cyanobacterial PKS-NRPS
enzymology and structural biology, biochemical profiling of DMSP
lyases, and more.
Black holes entered the world of science fiction and films in the
1960s, and their popularity in our culture remains today. The buzz
surrounding black holes was and is due, in large part, to their
speculative nature. It is still difficult for the general public to
determine fact versus fiction as it pertains to this terrifying
idea: something big enough to swallow anything and everything in
close proximity, with a gravitational force so strong that nothing,
including light, can escape. In the fall of 2015, scientists at the
Laser Interferometry Gravitational-Wave Observatory (LIGO) detected
the first sounds from black holes, brought to earth by the
gravitational waves that emitted from the merging of two black
holes 1.4 billion light years away in space. This confirmed the
existence of gravitational waves, which Albert Einstein predicted
in 1916. In the spring of 2017, physicists and astronomers who were
working on the Event Horizon Telescope (EHT) project captured the
first image of a black hole. This was the supermassive black hole
hosted by the galaxy M87 in the constellation Virgo, 53 million
light years away, and the image shows the shadow the black hole
casts upon the bright light surrounding it. In this book, John
Moffat shares the history of black holes and presents the latest
research into these mysterious celestial objects, including the
astounding results from gravitational wave detection and the shadow
of the black hole.
This book provides a general introduction to nanogels, and designs
of various stimuli-sensitive nanogels that are able to control drug
release in response to specific stimuli. Nanogels are
three-dimensional nanosized networks that formed by physically or
chemically crosslinking polymers. They have highly interesting
properties such as biocompatibility, high stability, particle size
adjustment, drug loading capability and modification of the surface
for active targeting. They can respond to stimuli which results in
the controlled release of drug and targeting of the site.
This book presents the fundamentals and the state of the art of the
photophysics of molecular oxygen. The author examines optical
transitions between the lowest-lying electronic states in molecular
oxygen and how these transitions respond to perturbation, either
from an organic molecule or from the plasmon field of a metal
nanoparticle. We live on a planet filled with light and oxygen. The
interaction between these two components forms the basis of excited
state chemistry spanning the fields of synthetic organic chemistry,
materials chemistry, molecular biology, and photodynamic treatment
of cancer. Still, the fundamental ways in which oxygen is affected
by light is an active subject of research and is continually being
developed and rationalized. In this book, readers will learn that
singlet oxygen, the excited state of oxygen that exhibits unique
chemical reactivity, can be selectively made via direct optical
excitation of oxygen in a sensitizer-free system. Readers will also
discover that this approach can perturb living cells differently
depending on the singlet oxygen "dose".
Biophysical Basis of Physiology and Calcium Signaling Mechanism in
Cardiac and Smooth Muscle acts as a bridge between physiology and
physics by discussing the physiology and calcium signaling
mechanism in cardiac and smooth muscle. By exploring the mechanism
of the cyclic release of stored Ca^(2+) in the SR or ER, this book
covers the cell communication system, including excitable cells,
recognizing the most relevant mechanisms of cell communication.
Serving as a bridge between physiology and physics, coverage spans
the physiology and calcium signaling mechanism in cardiac and
smooth muscle, offering insight to physiological scientists,
pharmaceutical scientists, medical doctors, biologists and
physicists.
At the heart of this book is the generalized theoretical approach
that is applied to investigate the geoelectrical structure of the
Earth's mantle. It also analyzes the results of regional and global
induction sounding of the Earth's mantle and compares them with the
results obtained by other geophysical methods. The generalized
theoretical approach employs the Induction Law as a basis for
identifying extended relations between magnetic field components,
including their plane divergence, impedances and spatial
derivatives. The estimations of impedance values and spatial
derivatives are performed using the theory of stochastic processes.
The book also considers the external sources of magnetic fields
used for sounding the Earths mantle from the modern theory
perspective, as well as the problem of coincidence of
magneto-variation and magnetotelluric methods. Further, it
discusses secular variations in the Earth's resistance caused by
non-induction sources, factors that are correlated with the number
of earthquakes in the region and shifted in time with global
indexes. It is a valuable resource for scientists applying deep
induction soundings or interested in the structures of and
processes in the Earth's interior.
This book focuses on the microscopic understanding of the function
of organic semiconductors. By tracing the link between their
morphological structure and electronic properties across multiple
scales, it represents an important advance in this direction.
Organic semiconductors are materials at the interface between hard
and soft matter: they combine structural variability,
processibility and mechanical flexibility with the ability to
efficiently transport charge and energy. This unique set of
properties makes them a promising class of materials for electronic
devices, including organic solar cells and light-emitting diodes.
Understanding their function at the microscopic scale - the goal of
this work - is a prerequisite for the rational design and
optimization of the underlying materials. Based on new multiscale
simulation protocols, the book studies the complex interplay
between molecular architecture, supramolecular organization and
electronic structure in order to reveal why some materials perform
well - and why others do not. In particular, by examining the
long-range effects that interrelate microscopic states and
mesoscopic structure in these materials, the book provides
qualitative and quantitative insights into e.g. the
charge-generation process, which also serve as a basis for new
optimization strategies.
This thesis focuses on theoretical analysis of the sophisticated
ultrafast optical experiments that probe the crucial first few
picoseconds of quantum light harvesting, making an important
contribution to quantum biology, an exciting new field at the
intersection of condensed matter, physical chemistry and biology.
It provides new insights into the role of vibrational dynamics
during singlet fission of organic pentacene thin films, and
targeting the importance of vibrational dynamics in the design of
nanoscale organic light harvesting devices, it also develops a new
wavelet analysis technique to probe vibronic dynamics in
time-resolved nonlinear optical experiments. Lastly, the thesis
explores the theory of how non-linear "breather" vibrations are
excited and propagate in the disordered nanostructures of
photosynthetic proteins.
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