### Wettability modification of oil reservoir rocks studied by atomic force microscopy (AFM)

Sherifat Omokhuwa Yesufu-Rufai
In oil/brine/rock systems, oil recovery is influenced by the wetting preference of the rock surface, which is dependent on numerous factors including rock mineralogy, brine chemistry and reservoir temperature and pressure. These factors make the assessment of rock wettability challenging and subjective and extensive analysis is required to obtain reliable data. In this work, the alteration of surface wetting behaviour when the chemical environment is changed was studied in detail. It presents the fundamental characterisation...

### Improving patient assessment and outcomes in contaminated abdominal wall reconstruction.

Jonathan Daniel Hodgkinson
This work aims to comprehensively evaluate patient assessment and explore avenues to improve outcomes for patients undergoing contaminated abdominal wall reconstruction (CAWR). A systematic review was performed to establish current outcomes from CAWR. Evaluation of national Hospital Episode Statistics data demonstrated contamination is a key risk factor for hernia recurrence (HR) justifying evaluation in isolation from clean defects. Risk factors for the development of CAW defects were evaluated using national and local data. Factors including...

### Expanding the applications of Rapid Evaporative Ionisation Mass Spectrometry (REIMS): microbial detection, diagnostics and metabolic profiling

The swift diagnosis of infection and identification of the causative microorganism is imperative to improving patient outcomes. Traditional identification techniques rely on microbial culturing, which is time consuming, labour intensive and subject to interpretation. Molecular methods are expensive and require extensive sample preparation. Commercial MALDI-ToF systems have become integrated into clinical microbiology laboratory workflows due to their ease of use, low per-sample cost, and ability to reduce sample turnaround times by one day. Although these...

### The mechanics of transitional soils

Barabra Shipton
Over the past two decades research in soil mechanics has shown that the behaviour of clean sands can be described within a Critical State framework similar to that for clays. More recent research has identified that there are many intermediate graded soils for which these types of Critical State framework do not work. These soils have been called ‘transitional’ in that they have a grading and a mode of behaviour between that of clean sands...

### Time resolved X-ray absorption spectroscopy in Poly(3-hexylthiophene)

Douglas Garratt
This thesis details the extension of time resolved x-ray absorption spectroscopy to the study of organic photovoltaic (OPV) materials. These materials have attracted signi cant research interest due to the potential to provide low cost, thin, flexible solar cells which can be solution processed. Here, we apply a tabletop, high harmonic generation based soft x-ray source to static and time resolved x-ray absorption spectroscopy of poly(3-hexylthiophene) (P3HT), a widely studied material in OPV research. The...

### Investigating reaction systems for high-temperature thermochemical energy storage and discharge integrated with concentrated solar power

In this thesis, two distinct reversible chemical reactions were studied for thermochemical energy storage (TCES) applications with a focus on integration with concentrated solar power (CSP): the reversible hydration of calcium oxide with steam and the redox behavior of certain copper manganese mixed metal oxides. A holistic investigation approach was employed encompassing the study of reaction kinetics, reactor design, process configuration, and the performing of a techno-economic assessment. Kinetic data for the reactions was experimentally...

### Bioinspired needle steering: a mechanics-based model

Thomas Edward Watts
Increasing adoption of robotic assisted surgery has opened up the possibility of using novel surgical instruments with control complexity beyond the dexterity of a human user. Steerable needles are one such technology, developed within the research community to enable greater clinical access in minimally invasive surgical procedures. Of the numerous designs developed, the Programmable Bevel-tip Needle (PBN) is unique in that it does not rely on rotation about its long axis but instead steers via...

### Blast performance of composite sandwich structures with hybrid laminate skins

Emily Louise Rolfe
This research project has investigated the performance of composite sandwich panels with hybrid skins against air and underwater blast loading. The loads are equivalent to those that could arise from sea mine detonation. Composite sandwich materials offer many benefits over conventional ship building materials. However, due to their variability and subsequent unpredictability, widespread use of composite sandwich panels in structural applications across the naval industry has been slow. The panel variability and interactions between the...

### Carborane-induced deformation of polycyclic aromatic hydrocarbons, and their intriguing emissive properties

Carboranes, C2B10H12, are bulky, icosahedral cluster compounds, with unique molecular bonding and electronic properties. Since their discovery in the middle of the 19th century, they have been studied and used in a wide range of chemical fields, with the aims of exploiting their excellent thermal and chemical stability, electron-withdrawing capability, and, more recently, their ability to act as modifiers and promotors of photoluminescence (PL). The effects of carboranes on PL have now been widely reported...

### Improving the domain generalization and robustness of neural networks for medical imaging

Chen Chen
Deep neural networks are powerful tools to process medical images, with great potential to accelerate clinical workflows and facilitate large-scale studies. However, in order to achieve satisfactory performance at deployment, these networks generally require massive labeled data collected from various domains (e.g., hospitals, scanners), which is rarely available in practice. The main goal of this work is to improve the domain generalization and robustness of neural networks for medical imaging when labeled data is limited....

### Transition metal nitrides as alternative plasmonic materials

Ryan Bower
Plasmonic materials display high local field enhancements and enable the sub-wavelength confinement of light. This has applications in next-generation nanoscale photonic and optoelectronic devices, chemical and biological sensing, and efficient energy harvesting amongst others. However, the typical plasmonic materials, gold and silver, have intrinsic material limitations that prohibit their widespread use in practical plasmonic devices. These limitations include poor thermal stability, limited spectral tunability, and incompatibility with existing complementary metal-oxide-semiconductor (CMOS) device fabrication processes, in...

### A 2D atom interferometer accelerometer in the horizontal plane

Shane De Silva
The thesis presented here describes the construction and early testing of an atom interferometer able to measure horizontal accelerations along two orthogonal axes. An ultra-high vacuum chamber is built for this cold atom interferometry. Rubidium 87 atoms are prepared in a 2D$^+$ MOT and then directed into the main chamber where they are captured in a 3D MOT. The atoms are cooled from the MOT equilibrium temperature of $\sim$ \SI{140}{mK} down to a few $\mu$K...

### Graphene plasmon cavities

Xiaofei Xiao
In the past decades, we have witnessed the rapid growth of plasmonics, which is a field investigating the properties and applications of surface plasmon polaritons. Two key features of plasmons are that they enable us overcome the diffraction limit and they provide large field enhancement on the surface of metals. However, traditional surface plasmon polaritons have some significant drawbacks, such as high loss and low tunability. Fortunately, new materials with plasmon-like behaviour, such as graphene...

### Development of carbonic anhydrase mimics that target the inefficiencies of rubisco by increasing local CO2 concentration in situ

Jon George David Rains
It is predicted that the global population will be over 9.8 billion people by 2050. In order to meet this rise in population, an increase of at least 50% of crop yields will need to be achieved by this date. Increasing photosynthetic efficiency remains one of the few routes left for substantial increases in crop yields. Ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), the enzyme responsible for fixating carbon dioxide from the atmosphere, is one of the major...

### Modelling and analysing the impact of flexible technologies on market-based generation investment planning

Temitayo Oderinwale
In recent times, the value of flexibility potentials available at the demand side in addressing techno-economic challenges associated with the decarbonisation of power systems has attracted notable interest from governments, industry and academia. Notwithstanding these interests, its impacts on long-term power system planning has only been investigated using system cost minimisation models. Such models are inherited from the era of vertically integrated power utilities and cannot represent the profit-oriented decisions of the liberalised electricity industry....

### Investigation of Alexithymia and related psychological factors in relation to body mass index and obesity

Nurul Hanis Ramzi
Common obesity is thought to be the result of genetic variations influencing susceptibility to environmental circumstances related to food intake, mediated by appetite-regulating pathways, and also affected by emotional processing and other behavioural traits. Alexithymia is a psychological construct for emotional processing deficits, characterised by impaired identification and description of feelings, and externally-oriented thinking. Here, I investigate the relationship between alexithymia, measured by the 20-item Toronto Alexithymia scale (TAS-20), and adiposity in two Northern Finland...

### Reconfigurable nanowires for thermo-electric applications

Ali Hamid
Nano-structuration of bulk into nanowires and nanosheets has led to massive changes in device behaviour and to opportunities for designing novel devices that exploit these changes. The combination of these two consequences of nanoscale devices in integrated circuits will lead to further enhancements in their performance in the future. In this project, different novel device structures have been designed and their performance investigated using Sentaurus Technology Computer Aided Design (TCAD) software. Sentaurus TCAD is a...

### Regulation of monoallelic exclusion in trypanosoma brucei

James Budzak
Nuclear bodies play a crucial role in the compartmentalisation and regulation of gene expression. However, the importance of nuclear bodies in controlling gene expression in more diverse organisms is still largely unexplored. The early branching eukaryote Trypanosoma brucei has long been known to regulate expression of its Variant Surface Glycoprotein (VSG) genes using a unique nuclear body called the Expression Site Body (ESB). The ESB has been defined as an extra-nucleolar structure enriched in RNA...

### Upper mantle conditions in the North Atlantic Ocean and their implications for continental break-up

Zsófia Zalai
Mantle conditions during the opening of the North Atlantic Ocean and specifically the presence or otherwise of a deep mantle plume have been much debated. Current models fall into two groups: plume impingement and plate-driven models. The Plume model associates the arrival of the Icelandic plume with continental break-up of the North Atlantic and the observed excess magmatism is associated with passive upwelling and elevated mantle potential temperatures. However, the Plate model associates this excess...

### The instability of some time periodically forced flows

Gursharan Sagoo
In this thesis the instability of two viscous incompressible flows is discussed by using numerical and analytical methods. The first problem concerns the steady streaming flow, that is contained within a hollow stationary cylinder and induced by the transverse oscillation of a solid inner cylinder. The small gap limit is taken so that a series solution in odd powers of the angular variable is possible. From the studies by Hall & Papageorgiou [37] and Watson...

### Major faulting in London: relating tectonic-scale processes to site-scale engineering geology

Tom Morgan
Critical infrastructure projects in London increasingly encounter unexpected ground conditions caused by major faults in the near surface geology. Their presence challenges the traditional interpretation of minimal faulting, which stems from limited exposure and structural information, and historical misinterpretation. These major faults are now recognised as both a geological unknown and a geotechnical risk since their origins, extents and architectures are poorly constrained. This research investigates major faults in London to characterise them structurally and...

### Transient loading and dynamic response of structures due to pressure waves and deflagration

Hannes Lukas Gauch
Accidental deflagration of gas clouds poses a persisting safety risk in industries handling flammable substances. Today, the assessment of structures against accidental loads is an integral part of the design process of modules in, among others, the oil&gas industry. Simplified models to estimate structural loading and response to deflagration incidents are yet scarce, and are mostly extrapolated from models developed for military applications. In this thesis various aspects of the effects of deflagration waves on...

### Correlating bone micromechanics to nanoscale characteristics

Nouf Aldegaither
Bone’s biomechanical properties derive from the hierarchical arrangement of its constituents with toughening mechanisms acting at every length scale. At the nanoscale, bone is a natural composite material consisting of protein (90% collagen and 10% non-collagenous proteins), mineral, and water. These components, their complex arrangement, interactions between them, and organisation of the mineralised collagen fibrils, make bone a tough and strong composite. However, almost nothing is known about how these components contribute to bone’s toughness...

### Functional tumour heterogeneity in advanced ovarian cancer

Ratri Wulandari
High-grade serous ovarian cancer (HGSOC) is the most lethal gynaecological malignancy. It is characterised by high degrees of genomic instability and heterogeneity, with many patients initially responding to chemotherapy but ultimately relapsing as they develop of resistance to platinum chemotherapy. The diversity of platinum resistance mechanisms and complete lack of predictive biomarkers means that delivering the best treatment for ovarian cancer patients remains challenging. Novel therapies targeting the molecular pathways dysregulated in HGSOC are being...

### Performance and transferability of land use regression models for ultrafine particles in London, UK

Zhenchun Yang
Over the past twenty years, a novel air pollutant -Ultrafine Particles (UFP), has attracted attention from scientific researches. UFP are particulate matters with a diameter of less than 100 nm. Currently, there is inadequate evidence to make a conclusion of the independent health impacts of UFP due to a lack of exposure data as UFP are not regulated or routinely monitored. Land Use Regression (LUR) models have been increasingly used to predict intra-city variations of...

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#### Affiliations

• Imperial College London
1,541
• University of Oxford
25
• Chinese Academy of Medical Sciences & Peking Union Medical College
22
• University of Nottingham
20
• Johns Hopkins University
19
• Zhejiang University
17
• Harvard University
17
• University of Cambridge
15
• George Institute for Global Health
14
• UNSW Sydney
14