Download RMMP2002 - Department of Physics

Contents
Biographies
Professor Tony S Clough
Dr Simon J Doran
Dr Joe L Keddie
Professor Peter J McDonald
Dr Richard PL Sear
Dr Paul J Sellin
Professor Nicholas M Spyrou
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Project Titles
Professor Tony Clough
 Diffusion of Small Molecules in Polymers (Biological and Non-Biological)
Dr Simon Doran
 Development of an Optical Tomography Scanner for Radiation Dosimetry in
Radiotherapy Treatment Planning
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Dr Joe Keddie
 Pressure-Sensitive Adhesives: Surface Properties and Formation Mechanism
 Probing Polymer/Polymer Interfaces
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Dr Joe Keddie/Dr Richard Sear
 Adsorption of Polymers at the Solid/Liquid Interface
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Professor Peter McDonald
 Magnetic Resonance Imaging of Drug Release from Solid Polymer Matrices
 Magnetic Resonance Imaging of Granular Flows
 Magnetic Resonance Imaging of Silane Treatment Processes Applied to Cement
Based Materials
 Magnetic Resonance Imaging of Water Diffusion in Biologically Important Polymer
 The Development of Gas Phase NMR Porosimetry
Dr Richard Sear
 Phase Transitions in Driven Systems
 Theoretical Study of the Fastest Way to Crystallise a Protein
Dr Paul Sellin
 Characterisation of UV Photoconduction in CVD Diamond Films for use as
a Radiotherapy Megavoltage X-Ray Sensor
 Diamond Ion-Implanted Metal-Semiconductor Field Effect Transistors for Smart
Sensor Applications
 Investigation of Charge Transport of Pixellated Gallium Arsenide X-Ray Imaging
Sensors
Continued on next page……………………..
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Professor Nicholas Spyrou
 Boron Capture Neutron Therapy and Brain Composition
 Coincidence Tomography Using Cascade Gamma-Rays Compared to Positron
Emission Tomography and Application to Elemental Analysis and Functional Studies
 Hydrophilic Materials and Breast Tissue Characterisation
 Neutron Spectrometry for the Naval Nuclear Propulsion Program
 The Binding and Localisation of Radionuclides in Biological Systems using
Perturbed Angular Correlation Measurements
 The Use of Electrical Impedance Measurements Comparison with Scintigraphy
in Gastric Motility Investigations; Satiety in Man
 The Use of Monte Carlo Methods in Radiotherapy and Shielding of Medical
Linear Accelerators
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Please note that the above projects are not exhaustive. They are specific research projects
related to current academic research programmes. If you are interested in a topic or have a
specific interest, which is not listed above, please contact Professor Peter McDonald:
[email protected]
Phone: +44 (0)1483 686798
Fax: +44 (0)1483 686781
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Radiation, Materials and Medical Physics Group
Professor Anthony S Clough PhD (London), CPhys, FInstP
Professor of Physics
Tony Clough graduated from QMC London in 1965 from where he gained his PhD in 1969 in
Experimental Nuclear Physics. He has worked on Particle Physics, Nuclear Structure and Applied
Nuclear Physics experiments since then at Rutherford and Daresbury Laboratories (UK), CERN (Geneva),
TRIUMF (Vancouver) and Los Alamos (USA). For the past few years he has worked at Surrey’s own Ion
Beam facility initiating the application of nuclear analysis techniques to diffusion problems in polymers and
biological materials.
Dr Simon J Doran PhD (Cambridge)
Lecturer in Magnetic Resonance Imaging
Simon Doran graduated from Cambridge University in 1988 with a BA in Natural Sciences,
specialising in Physics and Theoretical Physics. He worked with Professor LD Hall’s MRI group in
Cambridge during his PhD, preparing a thesis on the role of quantitative relaxometry in MRI. He
was a European fellow at the INSERM (Institut National de la Santé et de la Recherche Médicale)
biomedical NMR laboratory in Grenoble, France from 1993–95, where he performed research into
novel techniques of fast MR imaging. He joined the University of Surrey in 1995 as a NHS-funded
lecturer in Magnetic Resonance Imaging and has since been working to establish closer links
between the University and local hospitals. He currently has an active collaboration with the MR
Section of the Institute of Cancer Research/Royal Marsden Hospital at Sutton.
Dr Joseph L Keddie B.A, BSc (Alfred, USA) MS, PhD (Cornell, USA)
Lecturer
Joe Keddie, a lecturer at Surrey since 1995, has primary research interests in probing polymer
surfaces and interfaces using techniques including ellipsometry, ion beam analysis, atomic force
microscopy and magnetic resonance imaging. Much of his research - often in collaboration with
other group members - studies the behaviour of waterborne polymer colloids (i.e. tiny polymer
particles dispersed in water) as they coalesce, dry and evolve. Previously, he was a researcher in
the Polymers and Colloids Group of the Cavendish Laboratory at the University of Cambridge,
where he developed the use of ellipsometry and environmental-SEM for the study of latex film
formation. He is the co-author of about 50 publications on thin film and surface analysis and holds
two US patents. He and collaborators have obtained substantial funding from several industries
including Avecia, Dow Corning, UCB, and ICI. He was awarded the Paterson Medal and Prize
from the Institute of Physics in recognition of his contributions to the study of polymer dynamics at
surfaces, in thin films and in colloidal dispersions and was also named a Fellow of the Institute.
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Professor Peter J McDonald BSc, PhD (Nottingham), CPhys, MInstP
Professor of Physics
Since joining the Physics Department in 1985, Peter McDonald has been instrumental in establishing
a vibrant NMR imaging group. He and his students have developed a variety of solid state imaging
techniques which compliment the liquid state methods now widely used for medical diagnosis and
have pioneered their application in a number of technologically important areas. Amongst the facilities
available for this work are unique facilities for stray field imaging. Recent applications work has
focussed on fluid transport in porous media ranging from zeolites as used in detergents to cement and
concrete for the building industry materials and to foodstuffs. Much of the work looks as liquid
transport in polymers for engineering, biological and biomedical applications. There is also a highly
innovative programme using magnetic resonance imaging to study the drying of aqueous dispersions
as used in, for example, paints. Peter McDonald is current chairman of the British Radio Frequency
Spectroscopy Group of the Institute of Physics and is a member of the Spatially Resolved Magnetic
Resonance Division Committee of the international Groupement Ampere. In 1994 he completed a
Department of Trade and Industry sponsored secondment to Unilever Research Port Sunlight
Laboratory and in 1998 a sabbatical visit to the University of Ulm, Germany. He is the current
chairman of the Radiation, Materials and Medical Physics Group and also of UniS Materials at Surrey.
Dr Richard PL Sear BSc, PhD (Sheffield)
Foundation Fund Lecturer
Richard Sear joined the Department in September 1998 as a lecturer. He works on understanding the
phase behaviour and structure of polymers, colloids and similar soft condensed matter systems. He
graduated from Sheffield University in 1992 with a BSc in Chemical Physics and then stayed on in
Sheffield to do a PhD with George Jackson in the Department of Chemistry. The PhD work was
mainly on associating liquids and liquid crystals. In October 1995, he moved to the FOM Institute for
Atomic and Molecular Physics where he worked as a Royal Society Fellow with Bela Mulder and
Daan Frenkel, on the phase behaviour of complex fluid mixtures. From October 1997 to August 1998
he worked with Bill Gelbart and Jim Heath at the Department of Chemistry and Biochemistry of the
University of California, Los Angeles on pattern formation by nanoparticles.
Dr Paul J Sellin BSc, PhD (Edinburgh)
Lecturer in Physics
Paul Sellin joined the Radiation Physics Research Group in 1998 to develop pixellated semiconductor
radiation detectors. He had previously been a Research Associate at the University of Sheffield for
four years where he was a member of the Particle Physics Group, developing radiation detectors
using Gallium Arsenide. His interests now include the development of Gallium Arsenide pixel
detectors for use in the imaging of synchrotron x-rays, the use of CVD diamond for radiation
detection, and the development of high speed data acquisition systems for pixellated devices.
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Professor Nicholas M Spyrou MPhil, DIC, MD, MANS
Professor of Physics
Nicholas Spyrou is Professor of Radiation and Medical Physics and Chairman of Medical Physics.
He is Director of the MSc course in Medical Physics and Co-ordinator of the BSc (Hons)/MPhys
courses in Physics with Medical Physics. His first degree was in Nuclear Engineering, followed by
postgraduate degrees and research in Reactor and Neutron Physics at Imperial College, London
where he was also a research associate. When he joined Surrey as a lecturer he was instrumental in
the setting up of the two MSc courses, in Medical Physics and in Radiation & Environmental
Protection. Both enjoy a worldwide reputation and attract ~50 students per year.
He has initiated a large number of research projects and developed a variety of novel methods using
ionising and non ionising radiation probes in order to study the structure and function of biological
systems, and more specifically their elemental composition and distribution. He is an international
authority on radioanalytical methods for determination of trace element concentrations in tissues and
fluids, has developed rapid techniques for the measurement of very short-lived radionuclides using
neutrons and charged particles and pioneered neutron induced gamma-ray emission tomography.
He has built up a significant research activity in the fundamental concepts of imaging and imaging
theory, detection systems and tomography in emission and transmission modes. Research in
positron emission tomography (PET) over the last 20 years has focused on novel methods of
detection, image reconstruction and applications to neurological diseases and cancer. Current
projects include: binding sites of elements in cells; proton micro tomography; electrical impedance
epigastrography for gastric motility, diabetes, cardiac aortic by-pass grafting, radiotherapy, dosimetry
and shielding for medical linear accelerators by development of neutron detectors. He has
supervised 66 research students to PhD degrees and over 300 MSc dissertations in Medical Physics
and in Radiation & Environmental Protection. He is the author of over 240 publications and has made
more than 250 presentations at international conferences. He is a member of many international
committees and an executive member of the Biology and Medicine Division of the American Nuclear
Society. He is also a member of the NHS-Knowledge Group Network, under the chairmanship of one
of the Chief Scientific Advisors, on instrumentation, equipment and imaging issues. He chairs the
sub-group on PET and cyclotrons for radionuclide production.
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Diffusion of Small Molecules in Polymers (Biological and Non-Biological)
Supervisor (s):
Co-Supervisor (s):
Professor AS Clough
To be confirmed
Major Aims:
 To measure diffusion profiles of small molecules in skin, hair and hydrophilic polymers.
Techniques used and source of expertise:
 MeV ion beam analysis.
 Surrey University Tandetran – New £1M Accelerator.
During the last few years we have developed an accelerator–based facility that allows us to measure diffusion
profiles of small molecules in almost any material. We use a 3He microbeam and a combination of nuclear
reaction analysis and ion induced x-ray detection. The combination of techniques is presently unique in the
world.
Projects we are currently working on include:
 Water diffusion in drug-release polymers.
 Water and chlorine diffusion into cements.
 Surfactant diffusion into hair.
 Deodorant diffusion into skin.
 Water diffusion in fibre-optic cables.
We collaborate extensively with industry and a student would benefit from a combination of academic and
commercially relevant work involving state of the art equipment, computing and straightforward
mathematical analysis.
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Development of an Optical Tomography Scanner for Radiation Dosimetry in
Radiotherapy Treatment Planning
Supervisor (s):
Co-Supervisor (s):
Dr SJ Doran
Dr E J Morton / Dr W B Gilboy
Major Aims:
 To design, simulation and construction of an optical tomography scanner.
 To acquire optical tomography data and comparison with Magnetic Resonance Imaging.
 To prepare gel samples for optical and MRI scanning.
Techniques used and source of expertise:
 Optical computed tomography — Physics Dept.
 Magnetic Resonance Imaging — Physics Dept., Institute of Cancer Research
The use and importance of radiotherapy have increased greatly over the past decades. A key goal of
modern conformal and brachytherapy techniques is improvement in the delivery of radiation dose, to allow
treatments with higher specificity to be given safely to patients. Augmented doses at the tumour site while
sparing healthy tissue lead to a higher percentage of successful treatments, to a reduced risk of
complication or recurrence and thus to a lower overall healthcare bill. However, increases in local dose and
dose-gradient require an ever more stringent quality control of the treatment delivery. So there is a pressing
need for an accurate method of measuring radiation dose with the following characteristics: (i) noninvasiveness; (ii) high spatial resolution; (iii) ability to make measurements over 3-D regions; (iv) speed,
ease of application and automated analysis of data.
3-D radiation dosimetry using optical tomography (OT) was first proposed in 1996 by Gore et al. [1], but by
the time of publication, the idea had already been independently suggested at the University of Surrey by
Dr. Gilboy and initial designs for a prototype scanner made. Radiation dosimetry by this method involves
scanning a particular type of gel that changes colour when it is irradiated. OT works on the same principal as
the X-ray CT, widely used in hospitals and industry, except that radiation in the visible spectrum is used. OT
has not been intensively developed in the past for the simple reason that most materials of interest are
opaque to these wavelengths. However, it is ideal for use in gel dosimetry, because the gels are transparent
and then change their optical absorption properties when they are irradiated.
OT methods have the key advantage, compared with Magnetic Resonance Imaging, the competing
technique, that the apparatus required is cheap enough to be installed in any hospital Medical Physics
department. The method that we propose has the potential of making 3-D acquisitions that are 1–2 orders of
magnitude quicker the equivalent MRI scan for a full 3-D volume.
The project will involve development of a second, improved, prototype OT scanner, including computer
simulation, development of reconstruction algorithms, assembly of the scanner components and interfacing
hardware to a PC platform. There will also be an opportunity to manufacture the gel samples and make
direct comparisons of the OT technique with Magnetic Resonance Imaging (performed at the Institute of
Cancer Research).
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JC Gore et al., “Radiation dose distributions in three dimensions from tomographic optical density
scanning of polymer gels: I. Development of an optical scanner”. Phys. Med. Biol., 1996. 41: p. 26952704.
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Pressure-Sensitive Adhesives:
Surface Properties and Formation Mechanisms
Supervisor (s):
Co-Supervisor (s):
Dr JL Keddie
Dr M Sferrazza
Major Aims:
 To develop the use of ellipsometry, atomic force microscopy and magnetic resonance imaging to
determine the surface structure of pressure-sensitive adhesives.
 To apply and extend existing mathematical models of film formation to consider the specific
parameters relevant to adhesives, such as viscoelasticity, drying rate and particle size.
 To gain insight into how and why the polymer particles composing the adhesive deform and
coalesce.
Techniques used and source of expertise:
 Spectroscopic ellipsometry (in the Physics Department).
 Atomic force microscopy (in the Department of Materials Science and Engineering).
 Magnetic Resonance Imaging (in the Physics Department).
 Physical testing (performed at UCB Chemicals in Belgium).
Pressure-sensitive adhesives (PSAs) are frequently encountered in everyday life on the back of sticky labels and
on envelopes. The technology of making these very useful "soft solids" has developed faster than the basic
scientific understanding of them. This research project will be conducted in close collaboration with UCB
Chemicals (in Belgium) who are funding a post-doctoral researcher to gain a fundamental into thei performance
and properties of PSAs. There will be obvious opportunity for industrial collaboration.
The adhesives are deposited from a waterborne dispersion of microscopic particles. There are many mysteries
remaining as to how and why these particles deform and coalesce to create a functional material1. How can the
particle coalescence be optimised? What determines the water profile during drying? How can the adhesive's
density and strength be controlled? Within the last two years, new models of drying2 and film formation3 in
colloidal materials have been developed. These provide a basic framework for experimental work that tackles
questions about adhesives.
This project will make use of the full battery of techniques available at the University for non-invasively probing
small particles and polymer surfaces, with particular emphasis on atomic force microscopy (AFM), magnetic
resonance imaging (MRI), and ellipsometry.
AFM is a powerful type of microscopy that uses a very fine stylus to lightly "tap" a surface. It provides
topographical information combined with spatial details of the surface viscoelasticity. MRI is used widely in
hospitals for clinical applications, but within the last decade it has been applied more often to materials, especially
by the Surrey group led by Prof Peter McDonald. This project will make use of a novel type of MRI developed at
Surrey that is particularly well-suited to the study of planar films and coatings. The technique provides onedimensional profiles of concentration and polymer mobility with resolution on the order of 5 m.
Ellipsometry is a very powerful optical analytical technique that has been used extensively over the past 30 years,
primarily in the study of semiconductors but increasingly more in the analysis of polymer thin films and interfaces.
The technique relies on the reflection of light with a known state of polarisation from a planar sample surface or
parallel interfaces. Ellipsometry measurements are sensitive to steps or gradients in complex optical constants.
Refractive index profiles are used to determine the thickness of films and adsorbed layers, interfacial widths and
surface roughness. Ellipsometry has an advantage of being a laboratory-based technique that is non-invasive
(unless of course, the specimen is light sensitive). Because the technique is relatively fast processes may be
studied as a function of time. Under good experimental conditions, ellipsometry can detect sub-monolayer
coverage on a surface. This research will use a state of the art spectroscopic ellipsometer in the School’s Soft
Solids Laboratory.
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JL Keddie, Materials Science and Engineering Reports (1997), 21, p.101-170
AF Routh and WB Russel, AIChE Journal (1998), 44, p.2088-2098
AF Routh and WB Russel, Langmuir (1999), 15, p.7762-7773
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Probing Polymer/Polymer Interfaces
Supervisor (s):
Co-Supervisor (s):
Dr JL Keddie
Dr M Sferrazza
Major Aims:
 To establish infrared ellipsometry, combined with visible ellipsometry, as a technique for the
non-invasive study of interfaces between two polymers.
 To use infrared ellipsometry to characterise the structure, bonding and dynamics at immiscible
polymer interfaces.
 To study the thermal expansivity and glass transition in polymer films at polymer/polymer
interfaces and near the air surface.
Techniques used and sources of expertise:
 Spectroscopic Ellipsometry (available in the Department).
 Infrared Ellipsometry (new state-of-the-art instrument is now available in the Department).
This fundamental research will address questions of great interest and importance in condensed
matter physics. Moreover, the results will be of direct relevance to technological applications of
polymers, including welding, adhesion, diffusion and wear. The research group benefits from
many collaborations with industry.
Ellipsometry is an optical technique that relies on the reflection of polarised light to probe the
structure of an interface between two media. Ellipsometry is well-established as a means of
characterising the dynamics of polymers in thin films. In particular, it can non-invasively determine
changes in film thickness as a thin film is heated. From such measurements, information is
gained about the polymer's thermal expansivity and its passage through the glass transition
(analogous to a melting transition). Previous work has shown that an air surface can lead to a
depression in the glass transition temperature of a polymer in comparison to the value obtained
from the bulk substance. Other studies have found that an attractive interface can influence the
polymer dynamics.
A limitation of conventional ellipsometry is that it relies on a difference in the refractive index in the
visible region. Thus, it is not suitable for studying most polymer films on similar polymer
substrates or buried at an interface between two polymers. A recent development in ellipsometry
is the use of infrared, rather than visible, radiation in order to provide chemical as well as structural
information. A state-of-the-art ellipsometer is now available in the Physics Department at the
University of Surrey. It is expected that the technique will be ideal for characterising bonding and
structure at polymer/polymer interfaces. This project will explore how the confinement of a thin
film between other polymers influences its dynamic behaviour. In related studies, the dynamics of
polymers in thin films on polymer substrates will be probed and compared to what is found on
inorganic substrates.
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Adsorption of Polymers at the Solid/Liquid Interface
Supervisor (s):
Co-Supervisor (s):
Dr JL Keddie / Dr RPL Sear
Professor PJ McDonald
Major Aims:
 To develop improved techniques of ellipsometry to measure the amount of polymer adsorbed
at a solid/liquid interface.
 To explore the effects of molecular weight distribution on the total amount adsorbed.
 To test existing and new theory of polymer adsorption using ellipsometry experiments.
Techniques used and source of expertise:
 Spectroscopic ellipsometry (JLK).
 Modeling (RPLS).
Many applications of polymers involve their sticking to the interface between solids and liquids. Among
these are detergents, paints (particles in water), foods processing, and biomedical applications. The theory
of adsorption for simple polymer adsorption is well-developed. Some recent theory, developed by Dr Sear
at the University of Surrey, predicts that the distribution of the sizes (i.e. molecular weights) of the polymer
has a profound effect on the total adsorbed amount1. This project aims to test the predictions of this theory.
Ellipsometry is a well-established optical technique for the analysis of interfaces. The technique can
measure thicknesses of layers to within the nearest Å! It has recently been used - along with neutron
reflectivity and atomic force microscopy - to determine the structure of nanometer-thick layers of molecules
adsorbed on a solid surface2. The technique can also determine the total amount "sticking" to an interface
(in units of mass per unit area)3. Improvements to the sample cell and the experimental apparatus - as part
of this project - should enable even more reliable measurements to be made.
The project will use commercially available polymers of controlled molecular weight and various distributions
of molecular weight to test thoroughly the predictions of theory. The polymers will be dissolved in either
water or organic solvent and then placed in the ellipsometry cell for measurements of adsorption onto
various substrates. After that, more complex systems, such as diblock copolymers and polyelectrolytes at
various pH values will be studied.
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RPL Sear, Journal of Chemical Physics, 111, pp. 2255-2258, 1999.
DA Styrkas, JL Keddie, JR Lu, TJ Su and PA Zhdan, Journal of Applied Physics, 85, pp. 868-875, 1999.
DA Styrkas et al., in Polymer Surfaces and Interfaces III, John Wiley and Sons, Chapter 1, 1999.
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Magnetic Resonance Imaging of Drug Release from Solid Polymer Matrices
Supervisor (s):
Co-Supervisor (s):
Professor PJ McDonald
Dr DC Stevens (Polymer Research Centre)
Major Aims:
 To better understand the mechanisms of drug release from solid polymer matrices so as to
enable more prescriptive design of slow drug release devices.
Techniques used and source of expertise:
 Magnetic Resonance Imaging
 Polymer Science
 Pharmacy
Controlled release is central to many existing and foreseen technologies including agriculture (slow release
of pesticides and fertilisers), foods (release of flavours), industrial protective coatings (functional paints such
as self-clean or self-repair) and pharmaceuticals (controlled release of drugs and care products). This last
area is perhaps the most important, both from quality of life and commercial perspectives. Consequently,
although aspects of this proposal are undoubtedly generic, the work focuses on pharmaceutical applications
of controlled release where benefit may be most immediate.
For controlled drug release, the drug is usually encapsulated in a polymer matrix from which it is slowly
released by the action of water once implanted or digested into the body. Improved quality of life follows
from targeted delivery, temporally uniform dose delivery, improved drug compliance and the like. The
pharmaceutical industry is highly regulated. It is therefore surprising how little basic understanding there is
of control release mechanisms of drugs from polymer matrices. New formulations and other advances
continue to arise primarily from trial-and-error laboratory practice. The primary aim of this project is to
remove some of this hit and miss and arrive at some understanding of generic processes, which will enable
more predictive formulation and drug delivery device design.
To that end, the applicants propose a study of basic mechanisms of drug release from polymer matrices
targeting three central delivery modes: [i] release of soluble drugs from fixed, insoluble matrices; [ii] release
of soluble and insoluble drugs from swelling matrices and [iii] release of insoluble drugs from soluble or
erodable matrices.
The programme extends a very productive study of liquid uptake into polymers using stray field and
conventional magnetic resonance imaging (MRI) carried at Surrey in recent years which has led to an
identification of a second mechanism of Case II liquid transport in polymers1 and a much improved
understanding of binary solvent ingress 2. The MRI methodology will now be complemented by other
chemical and physical structural characterisation methods to further understand the effects of matrix
microstructure and drug distribution. Wide ranging molecular spectroscopy, electron, Raman and scanning
probe microscopies and meso/microvoid characterisation methods will be used. These techniques will be
made available within the Polymer Research Centre at the University of Surrey under the leadership of the
co-applicant Dr GC Stevens. Strong pharmaceutical focus and relevance will be maintained by close
collaboration with Napp Pharmaceuticals based in Cambridge.
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PJ McDonald, J Godward, R Sackin, RPL Sear, ‘Surface Flux Limited Diffusion of Solvent into Polymer’,
Macromolecules, 34 (2001) 1048
R Sackin, E Ciampi, J Godward, JL Keddie and PJ McDonald, ‘Fickian Ingress of Binary Solvent
Mixtures into Glassy Polymer’, Macromolecules, 34, 890, (2001)
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Magnetic Resonance Imaging of Granular Flows
Supervisor (s):
Co-Supervisor (s);
Professor PJ McDonald (Magnetic Resonance)
Dr RPL Sear (Theory)
Major Aims:
 To visualise patterns occurring in granular flow and develop theoretical analysis of these
patterns.
Techniques used and source of expertise:
 Magnetic Resonance Imaging.
 Computational Techniques/Computing Theory.
Perhaps the newest and fastest growing area of experimental physics is the study of the flow of sand and
related systems called granular media. Five years ago there were about 20 papers per year on granular
media in The Physical Review (the most prestigious physics journal); now there are about 125 per year. We
know less about granular media than we do about neutron stars and yet it is so common. If a box containing
a granular medium is tipped on its side then the surface tends to slide under the influence of gravity while a
few cms from the surface very little happens You can try this using a box half full of muesli and the sliding
layer is easily visible. What is not easily visible is where the layer of moving muesli meets the static muesli.
For this MRI (Magnetic Resonance Imaging) is required. What is known is that, under certain circumstances,
and particularly those involving repetitive motion, particles of different shape and size separate into different
regions in some most surprising ways. This project will use MRI to look inside a flowing granular medium at
the development of some of these patterns.
The results of this experimental project will be compared with theoretical and computer calculations in
collaboration with Dr Sear to better understand the results.
Someone undertaking this project can expect to get a thorough introduction to magnetic resonance imaging.
They will also learn something of a critical problem which has long defeated process engineers but where
Physics might now just be able to provide some answers of real commercial value.
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Magnetic Resonance Imaging of Silane Treatment Processes Applied to Cement
Based Materials
Supervisor (s):
Co-Supervisor:
Professor PJ McDonald
Dr M Mulheron (Civil Engineering)
Major Aims:
 To develop a new method of hydrophobic coating of cement systems.
Techniques used and source of expertise:
 Magnetic Resonance Imaging.
 Cement engineering.
Ask most people about magnetic resonance imaging (MRI) and they will immediately think in terms of the
latest whole body and head scanners used in medical diagnosis and neurological science. But that need
not be the case. Magnetic resonance is making a large impact in many industrial settings. Already, the
petroleum industry uses MR for down bore hole well logging where it provides useful in-situ information on
rock-formation pore-size, permeability, oil/water content and oil viscosity. The food and chemicals industries
use it for manufacturing process control.
This project offers a student the opportunity to be in at the beginning of MR technological applications to
cements and concretes. Using state of the art, stray field imaging equipment and expertise at Surrey, Mike
Mulheron and Peter McDonald have been exploring the application processes and efficacy of conventional
silane hydrophobing treatments applied to building materials. The particular project involved here concerns
the development of a new method of vapour treating materials. The technology promises to be of value in
the preservation of historic structures.
In the fullness of time, and with the continual reduction in cost of computing, magnetic materials and
electronics, it is anticipated that MR will transfer to building site just as it has transferred to the coal face of
other industries. A student undertaking this project can expect to learn about this emergent technology and
to apply it to a civil engineering problem of current concern. The skills developed will potentially lead to
opportunities in a diverse range of areas both in civil engineering and in other industries.
Reference:
A Chowdhury, A Gillies, PJ McDonald & M Mulheron, Magazine of Concrete Research, 53 (2001) 347
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Magnetic Resonance Imaging of Water Diffusion in Biologically Important Polymers
Supervisor (s):
Co-Supervisor:
Professor PJ McDonald
Dr AHL Chamberlain (School of Biological Sciences)
Major Aims:
 To improve understanding of water transport in compressed polymer powders.
Techniques used and source of expertise:
 Magnetic Resonance Imaging.
 Bio-science sampling handling methodologies.
Magnetic resonance imaging has found widespread application in medical diagnostics and is now often the
imaging technique of choice for a wide range of clinical disorders. Less well known is the fact that magnetic
resonance imaging and its sister technique magnetic resonance spectroscopy are very powerful tools in the
hands of materials scientists.
The Physics Department at the University of Surrey hosts a world-wide unique suite of equipment for stray
field magnetic resonance imaging of materials systems. In an on going collaboration between Dr Tony
Chamberlain in the School of Biological Sciences and Dr Peter McDonald in Physics these facilities are
being used to study water diffusion in a range of bio-polymer systems. Most recently, they have developed a
new model of the water transport process in compacted beds of xanthan powder. A key aim of this new PhD
project is to obtain the magnetic resonance imaging data necessary to enable a rigorous analysis of the
model.
The proposed work is of relevance in two key areas: Food science and food processing and agro-sciences
including plant-soil-water interactions. In the former case, xanthan is a key component of processed food
where it is widely used as a thickener. The work is also relevant to an understanding of biofilms which form
on the exposed surfaces of process plant. These biofilms may act as a medium in which both spoilage and
pathogenic organisms may survive even under drying conditions.
Further information
EPSRC research studentships are likely to be available for this work to well qualified students coming from
either the physical or bio-sciences. A student following such a PhD as offered here would gain a substantive
training in magnetic resonance techniques, allowing them to pursue a subsequent career in this rapidly
developing field where job opportunities are currently plentiful. They would also gain widespread exposure
to a number of potential employers through the established industrial stray field imaging consortium at
Surrey.
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3
TD Hart, AHL Chamberlain, JM Lynch, B Newling and PJ McDonald “A stray field magnetic resonance
study of water diffusion in bacterial exopolysaccharides”, Enzyme and Microbial Technol. 24 (1999) 339.
I Hopkinson, RAL Jones, S Black, DM Lane and PJ McDonald “Fickian and Case II diffusion of water
into amylose: a stray field NMR study” Carbohydrate Polymers 34, (1997) 39.
U Goerke, AHL Chamberlain, EA Crilly and PJ McDonald, “A model of water transport into powdered
xanthan combining gel swelling and vapour transport”, Phys. Rev. E 62 (2000) 5353.
12
The Development of Gas Phase NMR Porosimetry
Supervisor (s):
Co-Supervisor (s):
Professor PJ McDonald
Dr SJ Doran
Major Aims:
 To further develop methods of gas phase NMR characterisations of porous media.
 To apply the newly developed techniques to one or more application.
Techniques used and source of expertise:
 Nuclear Magnetic Resonance.
 Magnetic Resonance Imaging.
To characterise the pore structure of porous media from foods to rocks to building materials and to washing
powders is a problem of immense commercial importance. In recent years, NMR of absorbed liquids has
come to the fore as a superlative technique for doing this. Information is available about pore structure, pore
connectivity, modes of pore filling and much else. The fact that the method is non-destructive and generally
rather quick to apply is just for the better.
But what about gases? There are some hints that gas NMR may be just as good, if not better in certain
systems, particularly cement based building materials. The objective of this project is to fully explore the
new opportunities offered by 19F NMR of fluorinated gases absorbed in porous materials. Some of the
questions to be answered include: How far do the models developed for liquid state work carry over to the
gas phase? To what extent is the much greater diffusivity of gas compared to liquid an advantage and to
what extent is the lower gas density a disadvantage? Can additional information gleaned from molecules
adsorbed on pore wall surfaces? What is the optimum field strength – high for high sensitivity or low for
reduced susceptibility / diffusion induced spin relaxation?
Access to a range of NMR systems will be guaranteed for this project which is sure to open up a number of
exciting applications opportunities.
The project requires a student with a mix of skills and interests. It will involve both theoretical and
experimental work – the design and testing of NMR pulse sequences for a start design – and offers the
student the opportunity to become involved in one or more collaborative application areas from which future
employment opportunities might well emerge. There is also a requirement for some computing, from
spectrometer programming right through to image analysis. The project is equally suited to students with
first degrees in Physics, Chemistry and Materials Science or Engineering.
13
Phase Transitions in Driven Systems
Supervisor (s):
Co-Supervisor (s):
Dr RPL Sear
Dr DA Faux
Major Aims:
 To apply computer simulation to better understanding transitions in flowing systems.
Techniques used and sources of expertise:
 Computer simulation.
Phase transitions in what are called equilibrium systems are both common and appear in undergraduate
physics degrees. The most familiar examples are the phase transitions of water: the freezing of liquid water
into ice and the boiling of liquid water into water vapour. Essentially, a phase transition is where a
substance changes qualitatively, for example in freezing it goes from being a liquid, which flows, to being a
crystal which is solid and doesn't flow. This PhD project would be to look at phase transitions, qualitative
changes or jumps in what are called driven systems. Such phase transitions don't appear on undergraduate
courses as yet because only a decade ago few people were working on them, but recently interest in them
has taken off. When we describe a system as being driven we mean that we are pumping energy into it in
some way, a common example is a flowing liquid or an electrical current, in both cases we are doing work
on the system, pumping energy into the system, and causing it to flow.
Computer simulation methods are very well suited to studying driven systems as it is easy to write a
program to simulate a driven system and then the results can be directly visualised to see what is going on,
therefore the main approach used in the project will be computer simulation. The project will study effects
like the formation of stripes and other patterns.
Finally a couple of points: The project is theoretical in nature not experimental, it involves computer
simulation. Also, it is pure science not applied, patterns such as those above will be studied to understand
them because they are there and because I am curious, not because money can be made from them.
Although having said that, people want to make computerchips out of stripe patterns like those just above,
the stripes could form the templates for the wires of a computer chip.
There is further information at my web pages: http://www.ph.surrey.ac.uk/~phs1rs.
14
Theoretical Study of the Fastest Way to Crystallise a Protein
Supervisor (s):
Co-Supervisor (s):
Dr RPL Sear
Dr DA Faux
Major Aims:
 To apply statistical mechanical theory to find the conditions under which crystallization is
fastest.
Techniques used and source of expertise:
 Simple analytical theory and number crunching.
Phase transitions in what are called equilibrium systems are both common and appear in undergraduate
physics degrees. The most familiar examples are the phase transitions of water: the freezing of liquid water
into ice and the boiling of liquid water into water vapour. Essentially, a phase transition is where a
substance changes qualitatively, for example in freezing it goes from being a liquid, which flows, to being a
crystal which is solid and doesn't flow. This PhD project would be to look at the dynamics of equilibrium
phase transitions, i.e., how a phase transition such as the freezing of liquid water into ice occurs. A phase
transition like freezing is started off by heterogeneous nucleation. What happens is that a tiny, only a few
molecules across, crystal of ice forms at a surface in contact with the water. For example, if you are making
ice cubes then the ice crystals will start to form either at the walls of the plastic ice-cube holder or on tiny dirt
particles in the water (no water, certainly not tap water is completely free from dirt particles).
Heterogeneous nucleation is an activated process, for the nucleus of the ice crystal, or of any other phase,
to form a barrier must be crossed and the rate at which crystals form depends exponentially on the height of
the barrier. Indeed if the barrier is very high nucleation does not occur at all and the water won't freeze. The
project will study heterogeneous nucleation in particular how high the barrier is, not in water but in simple toy
models of proteins. The crystallisation of proteins is both an excellent playground for looking at the physics
of crystallisation and a subject of great interest by molecular biologists. Typically crystallising a protein is
both very important to determining its all-important structure, and very difficult.
Finally a couple of points: The project is theoretical in nature not experimental, it involves computer
simulation of nucleation and possibly also some simple analytic calculations. Also, it is essentially pure
science not applied, nucleation will be studied because it is interesting and because I am curious, not
because money can be made from them. Although having said that, protein crystallisation really is a very
important problem for many people.
There is further information in my web pages: http://www.ph.surrey.ac.uk/~phs1rs.
15
Characterisation of UV Photoconduction in CVD Diamond Films for use as a
Radiotherapy Megavoltage X-Ray Sensor
Supervisor (s):
Co-Supervisor (s):
Dr PJ Sellin
Dr EJ Morton
Major Aims:
 To experimentally investigate the signal response of sensors fabricated from CVD diamond films to
UV radiation.
 To investigate the performance of the hybrid sensor to megavoltage X-rays, for medical
applications by the coupling of a suitable scintillator to the diamond film.
 To compare the experimental sensor response to Monte Carlo simulations of charge transport in
CVD diamond.
Techniques used and source of expertise:
 Radiation measurements of the response of scintillator/diamond sensors to high energy x-rays.
 Characterisation and fabrication of CVD diamond sensors.
 Software modelling of sensor performance and comparison to experimental data.
This project is to study the performance of CVD diamond films for use as megavoltage X-ray detectors. The
proposed sensor will consist of a scintillator coupled to a CVD diamond detector. The scintillator acts as a
high efficiency X-ray photon conversion medium, producing UV photons, which are then detected in the
diamond sensor to produce a photocurrent. The particular application areas for the proposed device will be
in medical megavoltage X-ray detection, with other possible applications as ‘smart’ UV sensors for industrial
process control and monitoring.
Recently improvements in the quality of CVD diamond films have generated considerable interest in using
the material for sensor applications. Charge carrier lifetimes have increased to the level where significant
photocurrents are observed when illuminated with UV photons with wavelengths less than approximately
225 nm. As a result UV sensors can be fabricated which possess a unique range of properties derived from
the particular characteristics of diamond films. These include a sharp cut-off in sensitivity (by 6 orders of
magnitude) between far UV and visible light, a high tolerance of elevated temperature and harsh chemical
environments, and a high radiation tolerance. In addition the extremely high resistivity of diamond film
produces a sensor with very low dark currents and a correspondingly high dynamic range.
In this project a sensor will be developed to detect megavoltage X-rays, as produced from a cancer
radiotherapy machine. Such a device must have a high conversion efficiency for the X-ray photons
(achieved with the use of a suitable scintillator as an X-ray converter). It must produce an output signal with
a large signal to noise ratio, and must be highly radiation hard in order to operate after many hours of
accumulated dose from the X-ray beam. The proposed device is uniquely able to satisfy these criteria and
would be the first application of a diamond-based UV sensor for measurements of ionising radiation. Initial
measurements would characterise the photocurrents produced from specially prepared diamond films as a
function of wavelength in the UV region, so allowing the spectral photosensitivity to be deduced. A variety of
diamond sensors will be studied, fabricated using different diamond electrode patterns and geometries, in an
attempt to optimise the sensitivity of the devices. In addition there is some evidence that particular surface
treatments to the diamond films, such as annealing with particular gas mixtures, can improve the UV
sensitivity of the sensor.
Following this, the coupling of a scintillator to the diamond sensor will be investigated. Suitable optical
coupling greases will have to be chosen in order to maximise the transfer of UV photons between the two
surfaces, and the resulting light output from different sizes of scintillator will be measured. Computer
modelling methods such as Monte Carlo simulations can be used in parallel to verify the performance of the
device and optimise scintillator/diamond coupling. Finally the performance of the combined
scintillator/diamond detector will be characterised in realistic X-ray beams in terms of key parameters such
as sensitivity, dark current and radiation hardness. These measurements will make use of existing
collaborations with medical physicists at the nearby Royal Surrey County Hospital.
16
Diamond Ion-Implanted Metal-Semiconductor Field Effect Transistors for Smart
Sensor Applications
Supervisor (s):
Co-Supervisor (s):
Dr PJ Sellin
Dr EJ Morton
Major Aims:
 To fabricate MESFETs directly onto CVD diamond films using ion-beam implantation.
 To characterise the MESFET performance, in particular in terms of charge switches for use in
diamond smart sensors.
 To produce a prototype diamond smart sensor using a matrix of MESFET switches.
Techniques used and source of expertise:
 Device modelling of MESFETs in CVD diamond using commercial semiconductor software
modelling packages.
 Diamond MESFET fabrication using the University of Surrey’s Ion Beam Implantation Facility.
 Characterisation of the performance of CVD diamond MESFETs.
In this project it is proposed to fabricate unique ion-implanted metal-semiconductor field effect transistors
(MESFETs) on polycrystalline diamond film for the development of diamond-based smart sensors. Diamond
film offers a unique set of electrical and mechanical properties for electronic devices due to its high electron
and hole mobilities, wide band gap, large thermal conductivity and high saturated carrier velocity. Diamond
MESFETs potentially offer a fifty times improvement across the global range of transistor performance
parameters compared to comparable silicon devices. Recent studies have demonstrated a range of novel
biological, chemical and radiation sensors using this material that have exploited various properties of the
material such as chemical inertness, operation at high temperature, and ultra-violet sensitivity. In this
project ion-implanted diamond MESFETs will be investigated in terms of their electrical switching
characteristics. Such devices could then be integrated onto a film containing an array of diamond sensors to
provide charge readout and control circuitry and so realise a ‘smart’ diamond sensor.
A dedicated electro-optical characterisation system will be developed to evaluate the performance of the
MESFET structures. The characterisation system will perform low-noise current and voltage measurements
of the devices both in pulsed and DC modes, and will be fully automated via a personal computer and
associated software. Optical stimulation of the devices will be possible by back illumination of the films using
a focussed high intensity blue light emitting diode. Back illumination is possible because the majority of the
film thickness, which is non-implanted, is transparent and so insensitive to visible wavelengths. Optical
pulsing will be used to investigate the transient charge transport properties of the doped p-type transistor
channel.
The development of diamond MESFETs on polycrystalline film will be a unique achievement and have direct
relevance to a wide variety of commercial interests. Consequently there will be considerable scope for
liaison between the academic research group and industry.
An additional student stipend via an industrially sponsored CASE award may be available for this project.
17
Investigation of Charge Transport of Pixellated Gallium Arsenide
X-Ray Imaging Sensors
Supervisor (s):
Co-Supervisor (s):
Dr PJ Sellin
Dr EJ Morton
Major Aims:
 To simulate and model the charge transport properties of highly pixellated gallium arsenide X-ray
imaging sensors using Monte Carlo modeling techniques.
 To measure the signal response from highly pixellated Gallium Arsenide sensors and compare
the experimental data with the software models.
Techniques used and source of expertise:
 Monte Carlo simulation codes using C++.
 Optical and electrical semiconductor device characterisation.
 Radiation physics and nuclear measurement techniques.
Pixellated X-ray imaging sensors fabricated from semi-insulating Gallium Arsenide (GaAs) offer
considerable potential as high efficiency photon detectors for X-rays with energies in the range of
approximately 10 - 60 keV. GaAs is a material that has recently produced a lot of interest for use in radiation
sensors, in place of more conventional materials such as silicon. In this project the performance of
pixellated GaAs sensors will be modeled using a range of software tools, and compared with laboratory
measurements. The effects on device performance of very small pixel sizes will be investigated (the socalled “small pixel effect”) in an attempt to understand the performance of these devices in applications such
as digital medical X-ray imaging and Synchrotron X-ray imaging.
Initial Monte Carlo simulations of these devices have indicated that the use of small pixels (ie as small as 50
microns in diameter) tends to reduce the size of the signal pulse, due to distortion of the electric field in the
device close to the pixel contact. A complete simulation of this behaviour now needs to be carried out, in
particular by extending the simple models to a full 3-dimensional treatment including realistic geometries that
completely describe the small features of the pixellated devices. Monte Carlo simulations will be used,
programmed in C++, to follow the movement of individual charges through the sensor and so calculate the
induced signal observed at the sensor contacts. In addition a commercial 3-dimensional finite element
analysis program will be used to accurately calculate the internal electric field maps within the device, which
is then used as an input parameter to the Monte Carlo simulation.
In parallel with the simulation studies a variety of semiconductor characterisation techniques will be used to
experimentally measure the signal pulses from pixellated GaAs sensors that are fabricated within the
University. The group possesses a wide range of modern semiconductor characterisation equipment and
several dedicate laboratories. By careful measurement of the fast transient pulsed output from the sensors,
these data will be used to validate the software models.
The overall aim of the project will be to improve the spatial resolution and charge transport properties of
pixellated GaAs imaging sensors in order to bring these devices closer to realisation as commercial digital
X-ray sensors.
18
Boron Capture Neutron Therapy and Brain Composition
Supervisor (s):
Co-Supervisor (s):
Professor NM Spyrou
To be confirmed
Major Aims:
 To develop computer codes for determining neutron interactions in the human head for boron
neutron capture therapy (BNCT).
 To investigate brain composition and localisation of boron compounds for BNCT.
 To examine modes of “in-vivo” detection of neutron capture interactions for quality assurance.
Techniques used and source of expertise:
 Monte Carlo methods of neutron and photon interactions at variable energies.
 Radioanalytical methods, proton induced X-ray emission (PIXE) analysis, instrumentation
neutron activation’s analysis (INAA).
 Inductively coupled plasma mass spectrometry (ICPMS).
 Neutron transmission measurements.
Over the years research has concentrated on the elemental analysis and trace element distribution of biological
systems, developing techniques using proton beam microprobes and neutron induced short-lived nuclides for “in vitro”
measurements. Combined with the principles of tomography these provide powerful tools of investigation. The new
EPSRC funded charged particle accelerator, will further enhance capabilities for ion beam analysis and imaging.
Research for “in-vivo” medical applications is focused on the development of quantitative techniques in tomography, the
problems of detection, scattering and attenuation associated with PET and the benefits of carrying out simultaneous
emission and transmission 2D and 3D imaging. A position sensitive detector for charged particles and neutrons based
on dRAMs is at various stages of development, as are other novel neutron detectors and dosimeters using both
experimental and Monte Carlo calculations. The study of high-energy photon and neutron beams from medical linear
accelerators, dosimetry and radiation shielding is an important activity. Electrical impedance epigastrography has over
the past decade provided the means for measurements using a non-ionising radiation, non-invasive technique for
gastric motility.
Projects of current interest are:








Analysis of Alzheimer and normal brain, for trace elements.
Trace elements in diabetes and heart by-pass surgery.
The study of hydrophilic materials for phantoms.
Radiation beams and shielding of medical linear accelerators.
Simultaneous PET and transmission tomography.
Elemental composition of biological cells using a proton microprobe.
A novel neutron dosimeter and neutron spectrometers.
Gastric functions and motility.
Collaboration takes place with other University departments and other institutions such as the MRC Cyclotron Unit
Royal Postgraduate Medical School (London), the Nuclear Department (HMS Sultan, Gosport), the Gastrointestinal
Science Research Unit , The Wingate Institute (London), the Department of Radiography (City University, London), The
Intensive Treatment Unit, St George’s Hospital (London), the Portsmouth Hospitals, the University of Gröningen (The
Netherlands), the University of Pittsburgh (USA), the University of Ankara (Turkey) and the National Physical Laboratory
(UK).
Research in several of the projects is of a multidisciplinary nature and there are significant benefits to be gained from
these interactions. Collaboration between the Centre for Vision, Speech and Signal Processing (School of EEITM) and
the Physics Department is strengthened through the appointment of a Foundation Lecturer in medical imaging and the
development of research projects and co-supervised students in the field.
19
Coincidence Tomography Using Cascade Gamma–Rays Compared to Positron
Emission Tomography and Application to Elemental Analysis and Functional
Studies
Supervisor (s):
Co-Supervisor (s):
Professor NM Spyrou
To be confirmed
Major Aims:
 To establish the novel techniques of coincidence tomography using cascade gamma rays.
 To study usefulness of the technique in comparison with PET, its limitations and advantages.
 To study applications to neutron activated specimens for elemental analysis and in vivo functional
investigations (brain, tumours, transplants etc).
 To study Alzheimer’s and normal brain tissues.
Techniques used and source of expertise:
 Gamma-ray spectrometry and coincident counting.
 Positron emission tomography.
 Reconstruction methods of tomography.
 Measurement of gamma-ray spectra from irradiated samples.
 Determination of elemental composition using a new proton microprobe.
Over the years research has concentrated on the elemental analysis and trace element distribution of biological
systems, developing techniques using proton beam microprobes and neutron induced short-lived nuclides for “in vitro”
measurements. Combined with the principles of tomography these provide powerful tools of investigation. The new
EPSRC funded charged particle accelerator, will further enhance capabilities for ion beam analysis and imaging.
Research for “in-vivo” medical applications is focused on the development of quantitative techniques in tomography, the
problems of detection, scattering and attenuation associated with PET and the benefits of carrying out simultaneous
emission and transmission 2D and 3D imaging. A position sensitive detector for charged particles and neutrons based
on dRAMs is at various stages of development, as are other novel neutron detectors and dosimeters using both
experimental and Monte Carlo calculations. The study of high-energy photon and neutron beams from medical linear
accelerators, dosimetry and radiation shielding is an important activity. Electrical impedance epigastrography has over
the past decade provided the means for measurements using a non-ionising radiation, non-invasive technique for
gastric motility.
Projects of current interest are:








Analysis of Alzheimer and normal brain, for trace elements.
Trace elements in diabetes and heart by-pass surgery.
The study of hydrophilic materials for phantoms.
Radiation beams and shielding of medical linear accelerators.
Simultaneous PET and transmission tomography.
Elemental composition of biological cells using a proton microprobe.
A novel neutron dosimeter and neutron spectrometers.
Gastric functions and motility.
Collaboration takes place with other University departments and other institutions such as the MRC Cyclotron Unit
Royal Postgraduate Medical School (London), the Nuclear Department (HMS Sultan, Gosport), the Gastrointestinal
Science Research Unit , The Wingate Institute (London), the Department of Radiography (City University, London), The
Intensive Treatment Unit, St George’s Hospital (London), the Portsmouth Hospitals, the University of Gröningen (The
Netherlands), the University of Pittsburgh (USA), the University of Ankara (Turkey) and the National Physical Laboratory
(UK).
Research in several of the projects is of a multidisciplinary nature and there are significant benefits to be gained from
these interactions. Collaboration between the Centre for Vision, Speech and Signal Processing (School of EEITM) and
the Physics Department is strengthened through the appointment of a Foundation Lecturer in medical imaging and the
development of research projects and co-supervised students in the field.
20
Hydrophilic Materials and Breast Tissue Characterisation
Supervisor (s):
Co-Supervisor (s):
Professor NM Spyrou
To be confirmed
Major Aims:
 To develop a phantom made of hydrophilic materials and other mixtures for radiological and
radiotheraputical applications.
 To characterise hydrophilic materials and tissue using dual energy absorptiometry and
transmission tomography; additional information from energy dispersive X-ray diffraction (EDXRD)
and microprobe analysis techniques.
 To develop a specific phantom for breast tissue.
Techniques used and source of expertise:
 Accurate photon attenuation measurement.
 Transmission tomography using single, dual and multienergetic photons.
 Energy dispersive X-ray diffraction.
 Hydrophilic Materials Processing.
 Computer codes for attenuation and transmission tomography.
Over the years research has concentrated on the elemental analysis and trace element distribution of biological
systems, developing techniques using proton beam microprobes and neutron induced short-lived nuclides for “in vitro”
measurements. Combined with the principles of tomography these provide powerful tools of investigation. The new
EPSRC funded charged particle accelerator, will further enhance capabilities for ion beam analysis and imaging.
Research for “in-vivo” medical applications is focused on the development of quantitative techniques in tomography, the
problems of detection, scattering and attenuation associated with PET and the benefits of carrying out simultaneous
emission and transmission 2D and 3D imaging. A position sensitive detector for charged particles and neutrons based
on dRAMs is at various stages of development, as are other novel neutron detectors and dosimeters using both
experimental and Monte Carlo calculations. The study of high-energy photon and neutron beams from medical linear
accelerators, dosimetry and radiation shielding is an important activity. Electrical impedance epigastrography has over
the past decade provided the means for measurements using a non-ionising radiation, non-invasive technique for
gastric motility.
Projects of current interest are:








Analysis of Alzheimer and normal brain, for trace elements.
Trace elements in diabetes and heart by-pass surgery.
The study of hydrophilic materials for phantoms.
Radiation beams and shielding of medical linear accelerators.
Simultaneous PET and transmission tomography.
Elemental composition of biological cells using a proton microprobe.
A novel neutron dosimeter and neutron spectrometers.
Gastric functions and motility.
Collaboration takes place with other University departments and other institutions such as the MRC Cyclotron Unit
Royal Postgraduate Medical School (London), the Nuclear Department (HMS Sultan, Gosport), the Gastrointestinal
Science Research Unit , The Wingate Institute (London), the Department of Radiography (City University, London), The
Intensive Treatment Unit, St George’s Hospital (London), the Portsmouth Hospitals, the University of Gröningen (The
Netherlands), the University of Pittsburgh (USA), the University of Ankara (Turkey) and the National Physical Laboratory
(UK).
Research in several of the projects is of a multidisciplinary nature and there are significant benefits to be gained from
these interactions. Collaboration between the Centre for Vision, Speech and Signal Processing (School of EEITM) and
the Physics Department is strengthened through the appointment of a Foundation Lecturer in medical imaging and the
development of research projects and co-supervised students in the field.
21
Neutron Spectroscopyy for the Naval Nuclear Propulsion Program
Supervisor (s):
Co-Supervisor (s):
Professor NM Spyrou
Professor PA Beeley (Nuclear Dept, HMS Sultan, Gosport)
Major Aims:
 To develop a novel neutron spectrometry system to provide suitable spectroscopic and dosimetric
information for use in reactor fields.
 To consider detailed spectral information for application in more complicated neutron and gamma
fields and study the response of such a system.
 To provide information about the neutron fluence-to-dose function over the energy range (thermal
to 20MeV).
Techniques used and source of expertise:
 Neutron detection and spectrometry
 Digital pulse processing.
 Monte Carlo techniques.
 Neutron and gamma-ray dosimetry.
Over the years research has concentrated on the elemental analysis and trace element distribution of biological
systems, developing techniques using proton beam microprobes and neutron induced short-lived nuclides for “in vitro”
measurements. Combined with the principles of tomography these provide powerful tools of investigation. The new
EPSRC funded charged particle accelerator, will further enhance capabilities for ion beam analysis and imaging.
Research for “in-vivo” medical applications is focused on the development of quantitative techniques in tomography, the
problems of detection, scattering and attenuation associated with PET and the benefits of carrying out simultaneous
emission and transmission 2D and 3D imaging. A position sensitive detector for charged particles and neutrons based
on dRAMs is at various stages of development, as are other novel neutron detectors and dosimeters using both
experimental and Monte Carlo calculations. The study of high-energy photon and neutron beams from medical linear
accelerators, dosimetry and radiation shielding is an important activity. Electrical impedance epigastrography has over
the past decade provided the means for measurements using a non-ionising radiation, non-invasive technique for
gastric motility.
Projects of current interest are:








Analysis of Alzheimer and normal brain, for trace elements.
Trace elements in diabetes and heart by-pass surgery.
The study of hydrophilic materials for phantoms.
Radiation beams and shielding of medical linear accelerators.
Simultaneous PET and transmission tomography.
Elemental composition of biological cells using a proton microprobe.
A novel neutron dosimeter and neutron spectrometers.
Gastric functions and motility.
Collaboration takes place with other University departments and other institutions such as the MRC Cyclotron Unit
Royal Postgraduate Medical School (London), the Nuclear Department (HMS Sultan, Gosport), the Gastrointestinal
Science Research Unit , The Wingate Institute (London), the Department of Radiography (City University, London), The
Intensive Treatment Unit, St George’s Hospital (London), the Portsmouth Hospitals, the University of Gröningen (The
Netherlands), the University of Pittsburgh (USA), the University of Ankara (Turkey) and the National Physical Laboratory
(UK).
Research in several of the projects is of a multidisciplinary nature and there are significant benefits to be gained from
these interactions. Collaboration between the Centre for Vision, Speech and Signal Processing (School of EEITM) and
the Physics Department is strengthened through the appointment of a Foundation Lecturer in medical imaging and the
development of research projects and co-supervised students in the field.
22
The Binding and Localisation of Radionuclides in Biological Systems Using
Perturbed Angular Correlation Measurements
Supervisor (s):
Co-Supervisor (s):
Professor NM Spyrou
To be confirmed
Major Aims:
 To localise and measure the binding sites of trace elements of interest in biological systems.
 To identify radioisotopes of the elements of interest or analogues of these, which can be produced
in a research reactor or a cyclotron.
 To refine and enhance the present TDPAC system for repetitive, routine and more reliable
measurements.
 To develop a system using the existing small dimensions PET scanner
Techniques used and source of expertise:
 Gamma-ray spectrometry.
 Gamma-gamma angular correlation measurements in both time integrated and differential modes.
 Preparation and handling of radionuclides produced.
 Computer codes to TDPAC.
Over the years research has concentrated on the elemental analysis and trace element distribution of biological
systems, developing techniques using proton beam microprobes and neutron induced short-lived nuclides for “in vitro”
measurements. Combined with the principles of tomography these provide powerful tools of investigation. The new
EPSRC funded charged particle accelerator, will further enhance capabilities for ion beam analysis and imaging.
Research for “in-vivo” medical applications is focused on the development of quantitative techniques in tomography, the
problems of detection, scattering and attenuation associated with PET and the benefits of carrying out simultaneous
emission and transmission 2D and 3D imaging. A position sensitive detector for charged particles and neutrons based
on dRAMs is at various stages of development, as are other novel neutron detectors and dosimeters using both
experimental and Monte Carlo calculations. The study of high-energy photon and neutron beams from medical linear
accelerators, dosimetry and radiation shielding is an important activity. Electrical impedance epigastrography has over
the past decade provided the means for measurements using a non-ionising radiation, non-invasive technique for
gastric motility.
Projects of current interest are:








Analysis of Alzheimer and normal brain, for trace elements.
Trace elements in diabetes and heart by-pass surgery.
The study of hydrophilic materials for phantoms.
Radiation beams and shielding of medical linear accelerators.
Simultaneous PET and transmission tomography.
Elemental composition of biological cells using a proton microprobe.
A novel neutron dosimeter and neutron spectrometers.
Gastric functions and motility.
Collaboration takes place with other University departments and other institutions such as the MRC Cyclotron Unit
Royal Postgraduate Medical School (London), the Nuclear Department (HMS Sultan, Gosport), the Gastrointestinal
Science Research Unit , The Wingate Institute (London), the Department of Radiography (City University, London), The
Intensive Treatment Unit, St George’s Hospital (London), the Portsmouth Hospitals, the University of Gröningen (The
Netherlands), the University of Pittsburgh (USA), the University of Ankara (Turkey) and the National Physical Laboratory
(UK).
Research in several of the projects is of a multidisciplinary nature and there are significant benefits to be gained from
these interactions. Collaboration between the Centre for Vision, Speech and Signal Processing (School of EEITM) and
the Physics Department is strengthened through the appointment of a Foundation Lecturer in medical imaging and the
development of research projects and co-supervised students in the field.
23
The Use of Electrical Impedance Measurements Comparison with Scintigraphy in
Gastric Motility Investigations; Satiety in Man
Supervisor (s):
Co-Supervisor (s):
Professor NM Spyrou
Professor PJ Horton, Department of Medical Physics and
Dr AJ Sutton, Clinical Pharmacology Unit, Royal Surrey County
Hospital
Major Aims:
 To establish the technique of electrical impedance epigastrography in measuring stomach
emptying (flow) and contraction, for specific applications.
 To examine the possibility of using electrical impedance tomography (EIT).
 To aid the investigations into appetite and nutrition as well as clinical disorders of the GI tract.
 To associate clinical disorders of the GI tract, if time permits.
Techniques used and source of expertise:
 Electrical impedance epigastrography.
 Electrical impedance tomography.
 Signal processing and multivariate analysis of data.
Over the years research has concentrated on the elemental analysis and trace element distribution of biological
systems, developing techniques using proton beam microprobes and neutron induced short-lived nuclides for “in vitro”
measurements. Combined with the principles of tomography these provide powerful tools of investigation. The new
EPSRC funded charged particle accelerator, will further enhance capabilities for ion beam analysis and imaging.
Research for “in-vivo” medical applications is focused on the development of quantitative techniques in tomography, the
problems of detection, scattering and attenuation associated with PET and the benefits of carrying out simultaneous
emission and transmission 2D and 3D imaging. A position sensitive detector for charged particles and neutrons based
on dRAMs is at various stages of development, as are other novel neutron detectors and dosimeters using both
experimental and Monte Carlo calculations. The study of high-energy photon and neutron beams from medical linear
accelerators, dosimetry and radiation shielding is an important activity. Electrical impedance epigastrography has over
the past decade provided the means for measurements using a non-ionising radiation, non-invasive technique for
gastric motility.
Projects of current interest are:








Analysis of Alzheimer and normal brain, for trace elements.
Trace elements in diabetes and heart by-pass surgery.
The study of hydrophilic materials for phantoms.
Radiation beams and shielding of medical linear accelerators.
Simultaneous PET and transmission tomography.
Elemental composition of biological cells using a proton microprobe.
A novel neutron dosimeter and neutron spectrometers.
Gastric functions and motility.
Collaboration takes place with other University departments and other institutions such as the MRC Cyclotron Unit
Royal Postgraduate Medical School (London), the Nuclear Department (HMS Sultan, Gosport), the Gastrointestinal
Science Research Unit , The Wingate Institute (London), the Department of Radiography (City University, London), The
Intensive Treatment Unit, St George’s Hospital (London), the Portsmouth Hospitals, the University of Gröningen (The
Netherlands), the University of Pittsburgh (USA), the University of Ankara (Turkey) and the National Physical Laboratory
(UK).
Research in several of the projects is of a multidisciplinary nature and there are significant benefits to be gained from
these interactions. Collaboration between the Centre for Vision, Speech and Signal Processing (School of EEITM) and
the Physics Department is strengthened through the appointment of a Foundation Lecturer in medical imaging and the
development of research projects and co-supervised students in the field.
24
The Use of Monte Carlo Methods in Radiotherapy and Shielding of Medical Linear
Accelerators
Supervisor (s):
Co-Supervisor (s):
Professor NM Spyrou
Dr M Hosseini-Ashrafi (Portsmouth Hospitals)
Major Aims:
 To devise appropriate treatment planning regimes in intensity modulated radiotherapy.
 To provide radically new radiation shielding designs and experimentally validate calculations for
high energy medical linear accelerators, for both bremsstrahlung photons and neutrons.
Techniques used and source of expertise:
 Monte Carlo methods for modelling targets and shields.
 Radiotherapy planning.
 Gamma-ray and neutron detection and measurements.
 Dosimetry of photons and neutrons.
Over the years research has concentrated on the elemental analysis and trace element distribution of biological
systems, developing techniques using proton beam microprobes and neutron induced short-lived nuclides for “in vitro”
measurements. Combined with the principles of tomography these provide powerful tools of investigation. The new
EPSRC funded charged particle accelerator, will further enhance capabilities for ion beam analysis and imaging.
Research for “in-vivo” medical applications is focused on the development of quantitative techniques in tomography, the
problems of detection, scattering and attenuation associated with PET and the benefits of carrying out simultaneous
emission and transmission 2D and 3D imaging. A position sensitive detector for charged particles and neutrons based
on dRAMs is at various stages of development, as are other novel neutron detectors and dosimeters using both
experimental and Monte Carlo calculations. The study of high-energy photon and neutron beams from medical linear
accelerators, dosimetry and radiation shielding is an important activity. Electrical impedance epigastrography has over
the past decade provided the means for measurements using a non-ionising radiation, non-invasive technique for
gastric motility.
Projects of current interest are:








Analysis of Alzheimer and normal brain, for trace elements.
Trace elements in diabetes and heart by-pass surgery.
The study of hydrophilic materials for phantoms.
Radiation beams and shielding of medical linear accelerators.
Simultaneous PET and transmission tomography.
Elemental composition of biological cells using a proton microprobe.
A novel neutron dosimeter and neutron spectrometers.
Gastric functions and motility.
Collaboration takes place with other University departments and other institutions such as the MRC Cyclotron Unit
Royal Postgraduate Medical School (London), the Nuclear Department (HMS Sultan, Gosport), the Gastrointestinal
Science Research Unit , The Wingate Institute (London), the Department of Radiography (City University, London), The
Intensive Treatment Unit, St George’s Hospital (London), the Portsmouth Hospitals, the University of Gröningen (The
Netherlands), the University of Pittsburgh (USA), the University of Ankara (Turkey) and the National Physical Laboratory
(UK).
Research in several of the projects is of a multidisciplinary nature and there are significant benefits to be gained from
these interactions. Collaboration between the Centre for Vision, Speech and Signal Processing (School of EEITM) and
the Physics Department is strengthened through the appointment of a Foundation Lecturer in medical imaging and the
development of research projects and co-supervised students in the field.
25