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The ERC-funded FRAGSUS Project (Fragility and sustainability in small island environments: adaptation, cultural change and collapse in prehistory, 2013–18), led by Caroline Malone (Queens University Belfast) has explored issues of environmental fragility and Neolithic social resilience and sustainability during the Holocene period in the Maltese Islands. This, the first volume of three, presents the palaeo-environmental story of early Maltese landscapes. The project employed a programme of high-resolution chronological and stratigraphic investigations of the valley systems on Malta and Gozo. Buried deposits extracted through coring and geoarchaeological study yielded rich and chronologically controlled data that allow an important new understanding of environmental change in the islands. The study combined AMS radiocarbon and OSL chronologies with detailed palynological, molluscan and geoarchaeological analyses. These enable environmental reconstruction of prehistoric landscapes and the changing resources exploited by the islanders between the seventh and second millennia bc. The interdisciplinary studies combined with excavated economic and environmental materials from archaeological sites allows Temple landscapes to examine the dramatic and damaging impacts made by the first farming communities on the islands’ soil and resources. The project reveals the remarkable resilience of the soil-vegetational system of the island landscapes, as well as the adaptations made by Neolithic communities to harness their productivity, in the face of climatic change and inexorable soil erosion. Neolithic people evidently understood how to maintain soil fertility and cope with the inherently unstable changing landscapes of Malta. In contrast, second millennium bc Bronze Age societies failed to adapt effectively to the long-term aridifying trend so clearly highlighted in the soil and vegetation record. This failure led to severe and irreversible erosion and very different and short-lived socio-economic systems across the Maltese islands.

This is the data set associated with the journal article titled 'A Computationally Efficient Framework for Modelling Energy Consumption of ICE and Electric Vehicles'. The data files are in MATLAB file format. Figure 4 was generated using the vehicle speed profiles of an electric bus (EB) when it operated in London and of the EB's baseline simulation model, and using the state of charge (SOC) profiles of the EB when it operated in London and of the EB's baseline simulation model. Figure 5 was generated using the electricity consumption of the EB's baseline simulation model and of the EB's computationally efficient model for different drive cycles. It shows how the proposed computationally efficient model's electricity consumption compares with that of the baseline model. Figure 6 was generated using the speed profiles of a diesel heavy goods vehicle (HGV) when it operated on-road and of the HGV's baseline simulation model, and using the fuel consumption profiles of the diesel HGV when it operated on-road and of the HGV's baseline simulation model. It also contains the road elevation profile. Figure 7 was generated using the fuel consumption values of the diesel HGV's baseline simulation model and of the HGV's computationally efficient model for different drive cycles. It shows how the proposed computationally efficient model's diesel consumption compares with that of the baseline model. All the files were generated using MATLAB software package from Mathworks.

Frustration in the energy landscape has been quantified using a number of different metrics. These metrics have been applied to the databases in the subdirectories, which contain information about the energy landscape in the form of minima and transition states. The frustration metrics are coded within The PATHSAMPLE program, available for download at: http://www-wales.ch.cam.ac.uk/PATHSAMPLE/ Documentation can also be found at the same web address. The relevant keywords for the work described in this paper can be found at: http://www-wales.ch.cam.ac.uk/PATHSAMPLE.2.1.doc/node5.html Keywords CV, SHANNON and SHANNONR are described in the documentation. SHANNON and SHANNONR calculate frustration measures for the landscape as a function of temperature. The CV keyword gives a heat capacity calculation and hence allows an estimate of the melting temperature. Each Directory holds the database for the relevant system and input files for the PATHSAMPLE program. The output of the frustration calculation, for SHANNON, is given in Shannon.out. Some databases also contain output for the heat capacity calculation in CV.out. If required the OPTIM program is also available for download at: http://www-wales.ch.cam.ac.uk/OPTIM/ Documentation can also be found at the same web address. The program for drawing disconnectivity graphs, disconnectionDPS, can be found at: http://www-wales.ch.cam.ac.uk/software.html There is also input and output for the disconnectivity graph construction in each directory.

See the README file for a detailed description of the dataset. The data has been collected using a number of techniques. Figure 1 contains data gathered using photoelectron spectroscopy and have been saved in a .vms format. The data has been analysed and processed using CasaXPS and Origin respectively. Figure 2 contains data from photoluminescence and Transient absorbance spectroscopy and have been saved as .asc and .txt files. Figure 3 contains plots that have been gathered via X-ray diffraction and Time-of-flight Secondary Ion Mass spectroscopy techniques (ToF-SIMs). The ToF-SIMs data includes the response from all the species that evolves with ion bombardment but the species of interest are I2- and O2-. Figure 4 contains all the photovoltaic performance data in .txt format which can be opened and plotted using the Matlab script provided. The photovoltaic metrics, PCE, Jsc, VOC and FF have been generated with the Matlab script which can be taken forward for the box plot plotting as shown in Figure 4. Figure 5 is a summary of the PICTs data which has been derived from the raw data in Figure S11. Please see the ReadME files for more details.

Abstract for communication: "Bismuth-based compounds have recently gained increasing attention as potentially non-toxic and defect-tolerant solar absorbers. However, many of the new materials recently investigated show limited photovoltaic performance. Herein, we explore in detail one such compound through theory and experiment: bismuth oxyiodide (BiOI). We grow BiOI thin films by chemical vapor transport and find them to maintain the same tetragonal phase in ambient air for at least 197 days. Our computations suggest BiOI to be tolerant to antisite and vacancy defects. We demonstrate an all-inorganic solar cell (ITO|NiOx|BiOI|ZnO|Al) with negligible hysteresis and up to 80% external quantum efficiency under select monochromatic excitation. The short-circuit current densities and power conversion efficiencies under AM 1.5G illumination are nearly double those of previously-reported BiOI solar cells, as well as other bismuth halide and chalcohalide photovoltaics recently explored by many groups. Through a detailed loss analysis using optical characterization, photoemission spectroscopy and device modeling, we provide direction for future improvements in efficiency. Our work demonstrates that BiOI, previously considered to be a poor photocatalyst, is promising for photovoltaics."

Currently, fossil fuels make up a significant proportion of global energy demand and cause many concerns, such as increasing greenhouse gas emission. Therefore, there is a considerable need for cost-effective, facile and efficient processing of environmental-friendly energy harvesting and storage systems. Solar energy is one of the most promising energy sources that meet the energy demand. The silicon-based solar cells exhibit competitive power conversion efficiency and dominate the solar cell market in recent years. In contrast, organic solar cells (OSCs) have emerged as promising third-generation photovoltaic devices owing to their outstanding properties such as the potential of low-cost mass manufacturing, lightweight, mechanical flexibility and easy processability. Therefore, OSCs have received growing attention from the research community. For solar cell technologies, a smectic liquid crystal C8-BTBT was selected in Chapter 3 due to its unique thermal dynamic and crystal properties. A range of ternary OSCs with and without C8-BTBT loading at gradient weight fractions were thermally treated and fabricated. In addition, the assessment of fabricated OSCs on the photovoltaic characteristics reveals the evolution of various cell parameters with annealing temperature and C8-BTBT weight fractions. The cell with 5 wt% C8-BTBT loading exhibited the best performance after thermal annealing treatment at 120 oC. Furthermore, flexible hydrogel substrates were fabricated for flexible OSCs in Chapter 4. The PHEMA hydrogel films were optimised via adjusting photopolymerisation duration under UV light. Based on the fabricated PHEMA substrates, flexible OSCs were subsequently made, whose extracted device parameters showed comparable characteristics with those in Chapter 3. Moreover, PHEMA-based OSCs can be dissolved in different types of polar solvents, which is promising for realising sustainable and recyclable solar cells. For the development of energy storage devices, asymmetric carbon nanohorns were proposed as an active material to fabricate flexible solid‐state carbon wire (CW)‐based electrochemical supercapacitors (ss‐CWECs) which exhibited high power density and ultra‐low cutoff frequency. Based on microscopy and electrochemical characterisation, the fundamental reaction mechanism in polyvinyl‐based electrolyte system was elucidated in Chapter 5, as being associated with deprotonation reaction under the acid, base, and elevated temperature conditions. In Chapter 6, by using activated carbon, multi‐walled carbon nanotubes, and single‐wall carbon nanohorns as hybrid electrode materials (5:1:1), remarkable specific length capacitance of 48.76 mF cm−1 and charge-discharge stability (over 2000 times cycles) of ss‐CWECs were demonstrated, which are the highest reported to date. Furthermore, a high‐pass filter for eliminating ultra‐low electronic noise was demonstrated, enabling an optical Morse Code communication system to be operated. vThe collective works in this thesis demonstrate novel energy conversion and storage applications with the liquid crystal in OSCs and carbon nanoparticles in supercapacitors. These results provide a step forwards in the development of energy conversion and storage devices for a more efficient energy system.

It has been shown that the Fluoride Salt-Cooled High-Temperature Reactors (FHR) can benefit from adopting some features of well-established Advanced Gas-cooled Reactors (AGR) technology pioneered in the United Kingdom. AGRs offer a number of technological advantages that can potentially speed up the development of FHRs, such as experience with operation at high temperatures, graphite moderated core, fuel design, on-line refuelling, and experience in manufacturing and construction of large concrete pressure vessels with steel liners. This paper summarises relevant information available in the open literature on AGR core operation and design, focusing on neutronic characteristics. The obtained information was used to test the capabilities of Monte Carlo code Serpent to reproduce fuel temperature coefficient of a typical AGR. Then, the paper presents a neutronic analysis of the impact of CO2 coolant substitution with molten salt (FLiBe). The results obtained from the analysis showed that Serpent accurately reproduces the value and behaviour of fuel temperature coefficient both for fresh and depleted fuel conditions. However, subsequent sensitivity and uncertainty analysis showed high uncertainties in the calculated fuel temperature coefficients. The change of the coolant results in significant variation of an AGR neutronic characteristics. The analysis suggests that the use of FLiBe salt as a coolant in AGR-type reactors introduces additional design challenges related to the uncertainties in nuclear data. This work summarises an initial stage of AGRESR project, which was aiming to review the AGR technology relevant to FHR development.

The purpose of this research is to introduce a qualitative sustainability performance assessment framework for food supply networks, based on the perception of their key stakeholders’ upper management. Moreover, the paper provides industry insights by exemplifying the value of the proposed framework for the UK food industry. A critical review on the most acknowledged sustainability assessment methodologies and tools resulted in the synthesis of the proposed framework. An illustrative application follows, based on data from semi-structured interviews with C-level executives from key players of the UK poultry sector. The results demonstrate an easy-to-use approach, with a comprehensive and sharp outcome on supply chain sustainability performance assessment. Industry insights demonstrate an adequate sustainability performance with respect to the entire supply chain. A detailed view on different echelons reveals specific areas that could be improved, such as the environmental performance at both farming (production) and processing levels. This work extends the scope of current sustainability performance assessment tools by providing a tangible triple bottom-line overview, as well as echelon-specific and indicator-specific details, in a user-friendly, yet straightforward, way. UK food industry insights are valuable for practitioners and academics. The illustration is based exclusively on C-level executives’ viewpoint; thus, any generalization of the results should be considered to this effect. Supply chain stakeholders, policy-makers, and researchers could perform a quick and reliable supply network sustainability performance assessment.