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Dr. Beau Webber
Current Grants : EPSRC: Gas Hydrates in porous media. |
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Hi, I have, since shortly after the founding of the University of Kent,
been a member of the NMR group in the Physics Laboratory.
I was a founder member of the Physics Lab's Condensed Matter Group
and I am still closely associated with its successor,
the Functional Materials Group, in the now Department of Physical Sciences, as an Honorary Research Fellow.
I am now also a Senior Research Associate at Heriot-Watt University, in the Institute of Petroleum Engineering, working with two groups, the Centre for Gas Hydrate Research, and the Behaviour and Modeling of Faults/Fractures/Fluids Systems project. I am now also the director of a small nano-science and nano-metrology company, Lab-Tools Ltd. I study structured matter, mainly on the nano- to meso- to micro-scale: from about 1 Å up to a few µm, primarily using techniques based on NMR and neutron scattering. I do this both from a wish to study the novel properties of the matter, and also from a wish to apply this knowledge to the science of metrology over this nano-scale to micro-scale range. In particular, I study the behaviour of liquids in confined geometry, both at and near the surfaces of substrates. In both cases the physical properties of liquids are modified, sometimes substantially. |
 Functional Materials Group Some of my web pages : |
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First I study the properties of liquids in well characterised porous materials, such as sol-gel silicas, and the templated MCM and SBA-15 silicas. Then I apply this understanding to investigate the properties of uncharacterised porous materials, such as porous carbons, fired or un-fired clays, marine sediments, oil-bearing rocks, meteorite fragments ....
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Some older pages describing our techniques for functionalising and characterising porous materials.
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I specialise in combining results from different measuring techniques,
using computer based models, and also in designing novel measurement protocols.
The prime experimental techniques I use are :
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NMR Cryoporometry is a technique for measuring pore size distributions that we originated at Kent and are still further developing.
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Nano-structured liquidsWhen in pores, water can remain a stable liquid (i.e. in an equilibrium state) more than 20C° below its usual melting temperature - for other liquids the effect can be even larger. Even when ice is formed under these conditions, it can become much more mobile than normal brittle ice, particularly near surfaces.We now partly understand this behaviour in these confined systems, at least on the larger length scales, in terms of the changes in the thermodynamic state - in particular, alterations of the local Gibbs Free Energy. However there are still less-well understood effects, such as the effect of pore geometry on the thermodynamic state. As one approaches the atomic scale there is a need to use tools that take into consideration the atomic nature of the system. We are now beginning to apply ab-initio quantum mechanical molecular dynamic calculations to throw more light on the behaviour of liquids and their solids near surfaces (see figure). |
 3D model of laminar silicon porous system, with surface films of liquid nitrogen - one timestep from a CASTEP ab-initio QM MD simulation. |
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Follow the IoP link to see our invited paper :
Structural and Dynamic Studies of Water in
Mesoporous Silicas using Neutron Scattering and
Nuclear Magnetic Resonance.
Beau Webber and John Dore.
Invited article, IoP: Journal of Physics: Condensed Matter -
Special Issue: Water in Confined Geometry. 16, S5449-S5470, 2004. PII: S0953-8984(04)78970-5.
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 stacks.iop.org/JPhysCM/16/S5449 |
Water/ice systems at interfacesIt is our current belief, from measuring the nano-scale dynamics using NMR relaxation, that there is a layer about 1nm thick at ice interfaces where there is considerably enhanced rotational motion, resulting in the continual making and breaking of hydrogen bonds - "plastic ice". This may be the nano-scale view of the well-known need for plastic terms in the macroscopic viscous-plastic (VP) or elastic-viscous-plastic (EVP) dynamical models of ice and snow-packs in the environment.Follow the IoP link to see our paper : Plastic ice in confined geometry: The evidence from neutron diffraction and NMR relaxation. J. Beau W. Webber, John C Dore, John H. Strange, Ross Anderson, Bahman Tohidi. J. Phys.: Condens. Matter 19, 415117, 2007, Special Issue: Proceedings of The International Workshop On Current Challenges in Liquid and Glass Science (The Cosener's House, Abingdon, Uk, 10-12 January 2007). An invited review summarising this work has just been submitted : Studies of nano-structured liquids in confined geometry and at surfaces: phase, structural and dynamical changes due to confinement and the presence of silica and vapour interfaces. J. Beau W.Webber.
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stacks.iop.org/0953-8984/19/415117 |
ApplicationsInteresting though this behaviour is, in its own right, there are also important technological interests in studying such properties of liquids in pores, as the changes in melting point and mobility in confined geometry are indicators for other changes, such as the Gibbs Free Energy, that are relevant to many systems where properties are modified by nano-structure.Such cases are :
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This work has already indicated that for methane hydrate formed in the pore space of model systems,
there is a hysteresis in the phase plots.
The environmental impact of this difference between hydrate formation and dissociation temperatures is that, for a marine hydrate, a small rise in sea temperature (say, 0.1 K), which causes the dissociation of some hydrate and the release of some methane gas, may not be reversible by an equivalent drop in sea temperature but instead require a far greater temperature decrease before the hydrate can re-form. There is an urgent need to determine the magnitude this effect in real marine and lake sediments. Some preliminary answers are being obtained late in this project, now that we understand how to obtain them. Final Grant Report
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Our progress towards a better understanding, by applying NMR cryoporometry,
NMR relaxation and neutron diffraction studies, is covered in this list of our
published output during these two simultaneous grants, on the subject
of liquids in pores :
Grant related pore-liquid publications : 2003-04 to 2004-12
1) 1D NMR Cryoporometric structural studies of stratified geological samples.This is part of a larger project :Behaviour and Modeling of Faults/Fractures/Fluids Systems.The goal of BMFFFS is to make a step-change in the way that faults are considered in oil exploration and production strategies. The BMFFFS Project (Behaviour and Modelling of Faults/Fractures/Fluids Systems) is one of a set of six research projects concerned with the theme of "Structurally Complex Reservoirs". This large, themed programme of research - involving projects conducted by a number of international research groups- was brokered by the Industry Technology Facilitator on behalf of its member companies. This is an international project, on which four groups are working :
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bmfffs project home page |
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Rock Deformation Research Group (RDR), University of Leeds |
Department of Geology and Geophysics, Texas A&M University |
School of Physical Sciences, University of Kent, Canterbury. |
Naturally occurring methane clathrates have a number of features
that give them great significance :
Hydrate phase equilibria in porous media: effect of pore size and salinity Kasper K. Østergaard, Ross Anderson, Maria Llamedo and Bahman Tohidi. Terra Nova Volume 14 Issue 5 Page 307 - October 2002. NMR relaxation measurements offer an interesting way to characterise liquid and gas hydrates forming in porous media, particularly as these measurement may in principle be spatially resolved. The relaxation times are fast, but the apparatus at Kent is well able to resolve these signals. Initial studies have been made on liquid hydrates in sol-gel silicas. These preliminary studies resolved features that required more fundamental studies to be performed on pure water, in both sol-gel and the highly mono-modal SBA-15 silica, by both NMR relaxation and Neutron Diffraction (see the above IoP paper). |
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This application of NMR cryoporometry, to the study of pores in
melanin shells of fungi, is a novel application of cryoporometry into the
biological world.
These melanin 'ghosts' offer a clean system for NMR cryoporometry, as there are no changes to the bulk melting point caused by dissolved components in the water, all changes to the melting point coming from the Gibbs-Thomson dimensional effects on the thermodynamics of the system. Pore changes were related to the melanin treatment history. Publication : The Architecture of Cell Wall-Associated Melanin in the Human Pathogenic Fungus Cryptococcus Neoforman. Helene C. Eisenman, Joshua D. Nosanchuk, J. Beau W. Webber, Ray J. Emerson, Terri A. Camesano and Arturo Casadevall. Biochemistry, 44, 3683-3693, 2005. DOI: 10.1021/bi047731m |
Albert Einstein College of Medicine, Yeshiva University, NY |
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This Project was funded under the "Time-out for Reach-out" initiative.
Significant advances were made in updating SPS design technology capabilities, and a number of modes of out-reach were explored, including SME data bases, presentations at conferences, and web-based approaches. Funded projects have since been obtained as a result of this outreach. |
Anaylsis and nano- to micro- Metrology ServicesThe University of Kent School of Physical Sciences has the capability to perform both physical and chemical analyses.Details of physical analyses, concentrating on pore characterisation in the nano- to meso- scale, may be found on this page : www.kent.ac.uk/physical-sciences/nmr/nmr_contract.html, and of chemical analyses, at : www.kent.ac.uk/physical-sciences/tac/index.htm. Further information on our bulk metrology program on the nano- through meso- to micro- scale may be found on our nanometrology pages: |
 Our application of Nano-Science to Nano-Metrology, as analytic techniques for Industry and Academia. |
Instrumentation Design ServiceI specialise in designing novel measurement protocols, and have a strong ability to then implement these, using an appropriate combination of the latest hardware and software.I have sold NMR instrumentation internationally to 8 countries, and also have produced instrumentation for various other disciplines including fibre-optics. I can generate applications for MS Windows and Unix environments, and for Mac by agreement. 
I created, and was the original web-ring master for, the international web-ring for scientific instrumentation.
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Scientific Instrumentation and Software for Industry and Academia
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