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Book Review Magnetic Resonance Microscopy. Edited by B. Blmich and W. Kuhn

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those described earlier. These include current-voltage measurements of partially
ordered metal/functionalized polythiophene/metal structures (Umbach), and
the characterization and modification of
molecular materials by scanning tunneling microscopy (Rabe). The morphology
and electronic structure of conducting
polymers and the structure and dynamics
of monolayers of long-chain alkyl derivatives are being studied with the latter technique. Investigations of molecular packing, epitaxy with the substrate, defect and
domain mobility, and the ability to modify materials on the nanometer scale will be
of critical importance for the rational design of thin film structures. An important
aspect of nanoscale materials is their
chemical characterization, e.g., to obtain
information about composition, valence
states, and molecular energy levels. Photoemission spectroscopy provides detailed
information on these aspects, with
nanometer vertical sensitivity and lateral
resolution at the micron scale. A useful
overview of the technique and examples,
including conjugated polymer films on
metals, is given by Salaneck. The final
chapter by Gopel deals with the preparation of molecular thin film structures by
vapor deposition and their characterization under ultra-high vacuum (UHV) conditions, in particular the changes of structural and electronic properties observed
when one varies the coverage from submonolayer to monolayer and multilayer
thickness, and on exposure to gases such
as oxygen. Electron energy loss, photoemission spectroscopy, and conductivity
measurements of molecular sandwich
structures such as phthalocyanine films
are discussed.
In summary, this book provides a timely overview of research activities and concepts in the field of molecular electronics
and will be useful to readers with various
interests.
Thomas Bein
Department of Chemistry
Purdue University, Indiana (USA)
128
~
Magnetic Resonance Microscopy. Edited
by B. Blumich and W Kuhn. VCH Verlagsgesellschaft, Weinheim, 1992. X,
604 pp., hardcover DM 268.00.---ISBN
3-527-28403-6
Magnetic resonance (MR) microscopy
is an old idea which has only recently
started to attract increasing interest. It
arose out of the rapid development of M R
tomography for medical applications, but
it was not until quite late that efforts to
adapt the M R imaging principle to observe small volumes with high spatial
resolution were begun. The technique that
has developed from this work not only
gives high resolution in the pm range, but
has the further advantage of “speed”.
Thus, unlike routine MR imaging in
medicine, it is possible to obtain images
from substances with large natural
linewidths (solids in the extreme case)
with useful spatial resolution. These
two properties of an MR microscope
make possible a wide variety of applications.
This book collects together the papers
presented at the first International Conference on MR Microscopy, held in September 1991 in Heidelberg. Thus it is not
a textbook in the conventional sense, but
gives a picture of the state of the art in this
relatively new field. The contributions are
grouped in five chapters.
The first chapter deals with the fundamental principles of forming images of
substances with large natural linewidths.
All the authors are concerned with the
same subject. and consequently some repetition i s unavoidable. In the second article of this chapter W. S. Veeman gives a
lucid explanation of the problems of MR
imaging of solids and the various approaches to solving them. Readers with a
particular interest in the theory are well
served by the article by R. Kimmich,
which explains in detail many different
ways of generating three-dimensional images. Those who make the effort to work
carefully through this article will then
have an understanding of how “simple”
experiments can yield images of solid samples, and how even chemical shift imaging
is possible. The chapter ends with two interesting articles on imaging by electron
spin resonance (ESR).
The second chapter is concerned with
applications of the various imaging tech-
f~?;VCH Verlugsgesellschufi m h H , D-69451 Weinheim, 1994
~
~~~
niques to polymers and other solid-like
substances, and indicates the present limitations on resolution. Although there is
much repetition, the articles contain important information, for example on the
problem of artefacts caused by inclusions
in solids, which can make the experiments
difficult to perform successfully. There
are also interesting contributions describing dynamic studies of processes such as
photopolymerization and the imaging of
“chemical waves”.
The third chapter deals with measurements of flow and diffusion. Everyone involved in carrying out flow and diffusion
experiments (including routine tomography measurements) will benefit from the
help with theoretical and experimental
problems offered by these articles.
The fourth chapter shows, with examples of the images obtained, how the
high resolution capability of M R microscopy is being applied to studies of
plants.
The book concludes with a chapter
showing how the high spatial resolution
of M R microscopes and the very high sensitivity attainable by using high magnetic
field strengths can be used in biomedical
research. Possible applications include
those based on imaging of heteronuclides,
and localized spectroscopy of very small
volumes (also by ESR spectroscopy).
Who will benefit from this book? Newcomers to MR microscopy will not find it
easy to get to grips with the methodology
if they start here; they should first learn
something about conventional MR imaging before reading this book. On the other
hand, the reader wishing to learn about
the potential uses of an MR spectrometer
for the imaging of small specimens will
find all the relevant techniques and experiments described here. This book cannot,
of course, offer a systematic and exhaustive treatment of the capabilities and
problems along the lines of a textbook.
Here it might have been useful if the
editor had supplied an introduction
or a summary at the end of each chapter. Also the omission of the names of the
authors of the individual contributions
from the list of contents is rather unhelpful.
Hans Post
Bruker Medizintechnik
Rheinstetten (FRG)
nS7n-U833/94jUiof-O/2R3 10.00+ .25,U
Angrw. Chem. Irzt.
Ed. Engl. 1994, 33, N o . 1
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