VictorJuiz/thesis huggingface dataset:
Activation of small molecules by solid-supported frustrated Lewis pairs

The aims of this thesis have been to develop heterogeneous frustrated Lewis pairs for the catalytic activation of small molecules. Frustrated Lewis pairs capable of H2 activation and CO2 hydrogenation based on electron-deficient tri-aryl boranes and sterically encumbered phosphines have been immobilised on silica. The reactivity of these heterogeneous systems with small molecules has been tested and compared with a variety of soluble siloxane and silsesquioxane molecular models. The use of layered double hydroxides as a potential support for the immobilisation of FLPs has also been explored.
Chapter One introduces the methanol economy and provides a background to recent advances in CO2 capture and hydrogenation. The development of frustrated Lewis pairs, their reactivity with small molecules, together with theoretical studies on the mechanism of H2 cleavage and CO2 fixation by FLPs are summarised. Recent developments on heterogeneous frustrated Lewis pairs is discussed, in addition to a brief account of surface organometallic chemistry grafting procedures on silica and layered double hydroxide (LDH) supports.
Chapter Two reports H2 heterolytic cleavage by [B(C6Cl5)(C6F5)2/PtBu3] FLP and the H2 reduction of CO2 to give the methoxy borate [(C6Cl5)(C6F5)2BOCH3][HPtBu3]. These results are compared with formato- and methoxy borate derivatives prepared independently via reaction of formic acid and MeOH with [B(C6Cl5)(C6F5)2/PtBu3]. The products are characterised by FTIR and NMR spectroscopy, [(C6Cl5)(C6F5)2BOCHO][HPtBu3] is characterised by single crystal X-ray structure analysis.
Chapter Three details the synthesis of a group of siloxane and silsesquioxane bound Lewis acids [(tBuO)3SiOB(C6F5)2], [(tBuO)3SiOB(Fxyl)2] (Fxyl = 3,5-bis-trifluoromethylphenyl), [T8(OB(C6F5)2)2] (T8 = (C4H9)8Si8O12), [T8(OB(Fxyl)2)2], and preparation of the corresponding FLPs with Lewis bases PtBu3 and PMes3 as soluble molecular models for silica-immobilised FLPs. Their ability to activate H2 is investigated. The side-product ((tBuO)3Si)2OBC6F5 is characterised by single-crystal X-ray structure analysis.
Chapter Four describes the preparation of heterogeneous Lewis acids by immobilisation of -B(C6F5)2 and -B(Fxyl)2 on the surface of thermally pretreated silica, and the subsequent formation of the corresponding solid-supported FLPs (s-FLPs) by addition of PtBu3 to the Lewis acids. s-FLPs are shown to activate H2, D2 and CD3OD. The products are characterised by FTIR and solid state NMR (SSNMR) spectroscopy.
Chapter Five investigates the immobilisation of B(C6F5)2 on a thermally pretreated aqueous miscible organic layered double hydroxide (AMO-LDH) support, and formation of LDH FLP by the addition of a Lewis base, PtBu3. The B(C6F5)2 modified LDH-FLP is shown to react with H2 and D2 and the products are characterised by SSNMR and FTIR spectroscopy.
Chapter Six provides experimental procedures, characterisation techniques and data for those compounds described in the preceding chapters.

Advisor: O'Hare, D
Modelling the optical properties of semiconducting nanostructures

In this thesis we describe the development of a real-space implementation of the Bethe-Salpeter equation (BSE) and use it in conjunction with a semi-empirical tight-binding model to investigate the optoelectronic properties of colloidal quantum- confined nanostructures. This novel implementation exploits the limited radial extent and small size of the atomic orbital basis to treat finite systems containing up to &Tilde;4000 atoms in a fully many-body framework.
In the first part of this thesis our tight-binding model is initially benchmarked on zincblende CdSe nanocrystals, before subsequently being used to investigate the electronic states of zincblende CdSe nanoplatelets as a function of thickness. The band-edge electronic states are found to show minimal variation for a range of thicknesses and the results of our tight-binding model show good agreement with those predicted using a 14-band k·p model for a nanoplatelet of 4 monolayers (ML) in thickness. Optical absorption spectra were also computed in the independent-particle approximation. While the results of the tight-binding model show good agreement with those of the 14-band k·p model in the low-energy region of the spectrum, agreement with experiment was poor. This reflects the need for a many-body treatment of optical absorption in nanoplatelet systems.
In the second part of this thesis we apply our tight-binding plus BSE model to study the excitonic properties of CdSe nanocrystals and nanoplatelets. Simulations performed on CdSe nanocrystals examined an approximation of the BSE equivalent to configuration interaction singles (CIS), and found that both the optical gap and the low-energy spectral features were unaffected by the approximation. A comparison of exciton binding energies with those predicted by CIS demonstrates the sensitivity of results to the exact treatment of dielectric screening and the decision of whether or not to screen exchange. Our model predicts optical gaps that are in strong agreement with average experimental data for all but the smallest diameters, but was not able to reproduce low-energy spectral features that were fully consistent with experiment. This was attributed to the absence of the spin-orbit interaction in the model.
Simulations performed on CdSe nanoplatelets investigate the optical gaps and exciton binding energies as a function of thickness. Exciton binding energies were found to reach &Tilde;200 meV for the thinnest system, however, optical gaps were slightly overestimated in comparison to experiment. This is attributed to the reduced lateral dimensions used in our simulations and our bulk treatment of dielectric screening. A two-dimensional treatment of dielectric screening is expected to further increase binding energies. Calculations of the excitonic absorption spectrum reproduce the characteristic spectral features observed in experiment, and show strong agreement with the spectra of nanoplatelets, with thicknesses ranging from 3 ML to 5 ML.

Keywords: tight binding
exciton
excited state
Bethe Salpeter
optical properties
colloidal nanostructure
Advisor: Smith, J
Giustino, F
The political economy of Palestinians in Israel: encounters with development and neo-liberalization

The framework of ‘economic development’ has transformed the political economy of the Palestinians of 1948 (also known as Palestinian citizens of Israel). The discourse of development became increasingly assertive in the 2000s, and it has since redefined the way the Israeli government, private sector and an array of third sector organizations engage the Palestinian population. This dissertation analyzes the ways in which Palestinian citizens encounter economic transformations in Israel to provide a critique of the policy and discourse of development, its alignment with neo-liberalization, and the way it fulfils the goals of Zionism. It focuses on transformations in four sectors or spheres: (i) changes in consumption habits, seen as a path to modernity, (ii) efforts to de-segregate labor markets, (iii) ‘new’ industrial patterns under domestic outsourcing, and (iv) contestations among a neo-liberalizing faction of the Palestinian upper class that has embraced development.
Despite the rapid transformations that have taken place, the case studies demonstrate that the technology of development continues to build on essentialist relations and separatist dynamics, and it keeps Palestinians enframed as inferior, marked as cheaper ‘Arab labor.’ The continued reproduction of these categories, however, is not merely a reflection of inaction; it can be seen as an expression of a particular stage of neo-liberalization. It is part of a larger attempt to de-politicize the status of Palestinian citizens in Israel, using economic methods as a way to disempower political consciousness.
However, de-politicization is not necessarily successful, as the case studies reveal that Palestinian encounters with development have resulted in highly politicized encounters. Relying on ethnographic methodology, this dissertation focuses extensively on these subjective and affective encounters to analyze the ‘making’ of the economy, a discursive sphere and a site of political performance. The analysis represents an attempt to ‘re-claim’ the economic sphere and politicize the analysis of development.

Advisor: Armbrust, W
Hybrid methods for protein loop modelling

Loops are often vital for protein function, and therefore accurate prediction of their structures is highly desirable. A particularly important example is the H3 loop of antibodies. Antibodies are proteins of the immune system that are able to bind to a huge variety of different substances, in order to initiate their removal from the body. The binding characteristics of an antibody are mainly determined by the six loops, or complementarity determining regions, that make up their binding site. The most important of these is the H3 loop - however, since it is extremely variable in structure, the accuracy of H3 structure prediction is often poor.
Current loop modelling algorithms can mostly be divided into two categories: knowledge-based, where databases of fragments are searched to find suitable conformations; and ab initio, where conformations are generated computationally. In this thesis, we test the ability of such methods to predict H3 structures using one of each: the previously published, knowledge-based algorithm FREAD; and our own new ab initio method MECHANO.
Existing knowledge-based methods only use fragments that are the same length as the target, even though loops of slightly different lengths may adopt similar conformations. We describe the development of a novel algorithm, Sphinx, which combines ab initio techniques with the potential extra structural information contained within loops of a different length to improve structure prediction.
Finally we look at protein flexibility, by identifying loops for which there are multiple structures deposited in the PDB. We examine the outcome of performing structure prediction on loops with varying amounts of flexibility, and investigate differences between those loops that show a high degree of structural variability and those that do not.

Advisor: Deane, C
Shi, J
Neutron strain tomography

This thesis concerns the development of a technique known as ‘neutron strain tomography’, in order to non-destructively map, in three dimensions, residual elastic strain. The fundamental idea behind this research is that the strain values provided by through thickness transmission strain measurements are the result of averaging a number of strains within the sample. If a two-dimensional energy-resolving pixellated detector is used to record the transmission strains, a spatially resolved two-dimensional image of the average strain within the sample is obtained. This implies that if one records two-dimensional average strain data from the same sample from a number of different orientations there may be a route to reconstructing a set of higher dimensional volume data based on these two dimensional datasets.
The principle aim of this thesis has been to help develop neutron strain tomography into a viable tool for three-dimensional strain imaging. The main themes explored in this research are the generalisation of the method to arbitrary strain fields and its extension to high resolution strain 'imaging'.
Solutions and challenges associated with the first theme are outlined in chapters 2 and 3 which lay the theoretical foundations for the algorithms we employ in this research and the results obtained using these algorithms respectively. The second theme, resolution, is discussed in chapter 4 where the possibilities offered by high-resolution, energy resolving, neutron detectors is discussed in the context of neutron strain tomography. The descriptions of the algorithms, the comparison of possible approaches, and the improvements afforded by new detector technologies is intended to serve as an entry point guide for researchers wishing to further continue this work.

Advisor: Korsunsky, A
Data-level privacy through data perturbation in distributed multi-application environments

Wireless sensor networks used to have a main role as a monitoring tool for environmental purposes and animal tracking. This spectrum of applications, however, has dramatically grown in the past few years. Such evolution means that what used to be application-specific networks are now multi application environments, often with federation capabilities. This shift results in a challenging environment for data privacy, mainly caused by the broadening of the spectrum of data access points and involved entities.
This thesis first evaluates existing privacy preserving data aggregation techniques to determine how suitable they are for providing data privacy in this more elaborate environment. Such evaluation led to the design of the set difference attack, which explores the fact that they all rely purely on data aggregation to achieve privacy, which is shown through simulation not to be suitable to the task. It also indicates that some form of uncertainty is required in order to mitigate the attack. Another relevant finding is that the attack can also be effective against standalone networks, by exploring the node availability factor.
Uncertainty is achieved via the use of differential privacy, which offers a strong and formal privacy guarantee through data perturbation. In order to make it suitable to work in a wireless sensor network environment, which mainly deals with time-series data, two new approaches to address it have been proposed. These have a contrasting effect when it comes to utility and privacy levels, offering a flexible balance between privacy and data utility for sensed entities and data analysts/consumers.
Lastly, this thesis proposes a framework to assist in the design of privacy preserving data aggregation protocols to suit application needs while at the same time complying with desired privacy requirements. The framework's evaluation compares and contrasts several scenarios to demonstrate the level of flexibility and effectiveness that the designed protocols can provide.
Overall, this thesis demonstrates that data perturbation can be made significantly practical through the proposed framework. Although some problems remain, with further improvements to data correlation methods and better use of some intrinsic characteristics of such networks, the use of data perturbation may become a practical and efficient privacy preserving mechanism for wireless sensor networks.

Keywords: Data privacy
Data aggregation
Wireless Sensor Networks
Differential Privacy
Advisor: Brown, I
Martin, A
Beyond famines: wartime state, society, and politicization of food in colonial India, 1939 – 1945

This thesis explores the origin of one of the most engrossing concerns of the post-colonial Indian state, that is, its extensive, intricate, and expensive feeding arrangements for the civilians. It tracks the colonial origin of the post-colonial welfare state, of which state-management of food is one of the most publicized manifestations.
This thesis examines the intervention of the late colonial British state in food procurement and distribution in India during the Second World War, and various forms of such intervention, such as the introduction of food rationing and food austerity laws. It argues that the war necessitated actions on the part of the colonial state to secure food supplies to a vastly expanded British Indian Army, to the foreign Allied troops stationed in India, and to the workers employed in war-industries.
The thesis brings forth the constitutional and political predicaments that deprived the colonial central government’s food administration of success. It further reveals how the bitter bargaining about food imports into India between the Government of India and the War Cabinet in Britain hampered the state efforts to tackle the food crisis.
By discussing the religious and cultural codes vis-à-vis food consumption that influenced government food policies, this thesis has situated food in the historiography of consumption in colonial India. In addition to adopting a political approach to study food, it has also applied sociological treatment, particularly while dealing with how the wartime scarcity, and consequent austerity laws, forced people to accept novel consumption cultures. It also contributes to the historiography of ‘everyday state’. Through its wartime intervention in everyday food affairs, the colonial state that had been distant and abstract in the perception of most common households, suddenly became a reality to be dealt with in everyday life within the domestic site. Thus, the macro state penetrated micro levels of existence. The colonial state now even developed elaborate food surveillance to gather intelligence about violation of food laws.
This thesis unravels the responses of some of the political and religious organizations to state intervention in quotidian food consumption. Following in this vein, through a study of the political use of famine-relief in wartime Bengal, it introduces a new site to the study of communal politics in India, namely, propagation of Hindu communal politics through distribution of food by the Hindu Mahasabha party. Further, it demonstrates how the Muslim League government’s failure to prevent the Great Bengal Famine of 1943-44 was politically used by the Mahasabha to oppose the League’s emerging demand for the creation of Pakistan.

Keywords: communalism
Second World War
South Asia
food
famine-relief
India
rationing
communal politics
history
famine
Advisor: O'Hanlon, R
Necessity in international law

This thesis examines the role of necessity, as a defence to State responsibility, in international law. Necessity provides a State with a defence to the responsibility that would otherwise arise from its breach of an international obligation where the only way that State can safeguard an essential interest from a grave and imminent peril is to breach an obligation owed to a less imperilled State. It is a defence that has generated a considerable body of jurisprudence in recent years and yet it continues to be plagued by a perception that States have abused it in the past and by fears that States will abuse it in the future – 'necessity', declared the German Chancellor on the eve of World War I, 'knows no law'.
This thesis contends that this perception is flawed and these fears are unfounded. The main claim of this thesis is that necessity operates as a safety valve within the law of State responsibility that mediates between the binding quality of international obligations and the harsh consequences that may follow from requiring compliance with those obligations at all costs. This safety valve promotes the reasonable application of international law and it recognises that international law must sometimes bend so that it does not break. The thesis bears out this claim by contending that necessity has a stronger pedigree than is commonly appreciated and that it is solidly grounded in, and its contours are constrained by, customary international law. It charts those contours by first examining the scope of the obligations to which necessity may provide a defence, which includes examining how necessity relates to fields of law that contain their own safety valves regulating emergency situations. It then proceeds to examine the conditions that a State must satisfy in order to establish necessity and it finally examines the consequences of necessity, including for the stability of international law. The thesis concludes that any suggestion that 'necessity knows no law' has no place in international law today.

Keywords: State Responsibility
Emergency
Necessity
The lightscape of literary London, 1880-1950

From the first electric lights in London along Pall Mall, and in the Holborn Viaduct in 1878 to the nationalisation of National Grid in 1947, the narrative of the simple ascendency of a new technology over its outdated predecessor is essential to the way we have imagined electric light in London at the end of the nineteenth century. However, as this thesis will demonstrate, the interplay between gas and electric light-two co-existing and competing illuminary technologies-created a particular and peculiar landscape of light, a 'lightscape', setting London apart from its contemporaries throughout the late nineteenth and early twentieth centuries. Indeed, this narrative forms the basis of many assertions made in critical discussions of artificial illumination and technology in the late-twentieth century; however, this was not how electric light was understood at the time nor does it capture how electric light both captivated and eluded the imagination of contemporary Londoners.
The influence of the electric light in the representations of London is certainly a literary question, as many of those writing during this period of electrification are particularly attentive to the city's rich and diverse lightscape. Though this has yet to be made explicit in existing scholarship, electric lights are the nexus of several important and ongoing discourses in the study of Victorian, Post-Victorian, Modernist, and twentieth-century literature. This thesis will address how the literary influence of the electric light and its relationship with its illuminary predecessors transcends the widespread electrification of London to engage with an imaginary London, providing not only a connection with our past experiences and conceptions of the city, modernity, and technology but also an understanding of what Frank Mort describes as the 'long cultural reach of the nineteenth century into the post-war period' (218).

Keywords: Virginia Woolf
British literature
detective fiction
science fiction
spy fiction
modernism
literature and science
Arnold Bennett
gothic fiction
Advisor: Whitworth, M
Influence of eddies on vertical transport and nutrients in subtropical gyres

The presence of large-scale Ekman pumping associated with the climatological wind-stress curl is the textbook explanation for low biological activity in the subtropical gyres. Using an idealised model it is shown that Eulerian-mean Ekman pumping may be opposed by an eddy-driven circulation, analogous to the way in which the atmospheric Ferrel cell and the Southern Ocean Deacon cell are opposed by eddy-driven circulations. Potential vorticity fluxes, Lagrangian particle tracking, and depth-density streamfunctions are used to show that, in the model, the rectified effect of eddies acts to largely cancel the Eulerian-mean Ekman downwelling. To distinguish this effect from eddy compensation, it is proposed that the suppression of Eulerian-mean downwelling by eddies be called "eddy cancellation."
Eddy cancellation highlights that the thermocline forms a barrier between the surface waters and the abyssal ocean. The presence of this barrier suggests that the nutrient budget of the subtropical mode water and euphotic zone should be considered together. An idealised two-layer axisymmetric model of nutrient concentration in subtropical gyres is developed. This model is used to explore the concept of a unified nutrient budget for the euphotic zone and mode water of subtropical gyres. The steady-state nutrient distribution and fluxes from the idealised model are compared with observations and previous studies. These comparisons show that the solutions of the idealised model are reasonable. Following this validation the sensitivity of the model to changes in parameter values is explored. The model predicts a non-monotonic response to changes in the residual Ekman pumping velocity, with a productivity minimum at 30 m year -1. The model also predicts a positive relationship between primary productivity and mode water thickness. The predicted relationship between primary productivity and mode water thickness is tested using observational datasets, which provide some evidence to support the conclusion that thicker mode waters lead to higher productivity in the oligotrophic gyres.

Advisor: Marshall, D