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Research data supporting the full paper entitled "Snail shell derived magnetic nanocatalysts for biodiesel production: Process optimization through response surface methodology, kinetics, and thermodynamic studies" by S. Ao et al. in Biomass and Bioenergy. A heterogeneous biomass-based catalyst based on CaO derived from snail shells and magnetite nanoparticles was used and recycled in the generation of biodiesel from Soybean oil. The following supporting data that characterizes the fresh and recycled catalyst and also the product(s) of biodiesel formation are deposited here: X-ray powder diffraction (XRD) data from a PANalytical X’Pert Pro diffractometer. Cu Kα radiation was used over 2theta = 10-60°, and with 40 kV and 100 mA as functional voltage and current, respectively. Fourier Transform Infrared (FT-IR) analyses in the range 400–4000 cm-1 from a Bruker 3000 HYPERION FT-IR spectrometer. Thermogravimetric analysis (TGA) from a TG/DTA (Netzsch Geratebau GMBH, model no. STA 409) under air flow of 1.5 bar and 2 L h-1. Scanning electron microscopy (SEM) images, acquired at 5kV and energy dispersive X-ray spectroscopy (EDS) data and maps acquired at 10kV on a TESCAN MIRA3 FEG-SEM equipped with an Oxford Instruments X-maxN 80 EDS detector. Prior to SEM-EDS, samples were sputter coated with 10 nm of Pt using a Quorum Technologies Q150T ES coater. Elemental composition from an Elementar Vari EL Cube (Germany). A Quantachrome® ASiQwin™ instrument was used for analysis by the Brunauer-Emmett-Teller (BET) and pore volume analyser at 77 K through N2 adsorption-desorption processes. X-ray photoelectron spectroscopy (XPS) examination using an ESCALAB Xi+ system with a micro-focused dual-anode Al/Mg K source. Temperature-programmed desorption using a flow of helium (100 cm3 min-1) whilst heating the samples to 50 °C at a rate of 5 °C min-1. A stream of CO2 was permitted to flow over the sample after 30 minutes at this temperature. Physisorbed species were removed from the sample by passing it through a flow of helium for one hour at a rate of 100 cm3 min-1. The desorption of NH3 and CO2 was measured with a flow of helium gas at 900 °C and a temperature ramp-rate of 10 °C min-1. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) and C, H, N elemental analyses using a Thermo Scientific iCAP 7400 ICP-OES spectrometer and an Exeter analytical CE 440 elemental analyser (975 °C), respectively. Vibrating-sample magnetometer (VSM) data obtained from a Lake Shore 7410 series instrument. The magnetometer was calibrated using a nickel reference sphere. A 1.5 Tesla applied field maximum was used for the tests. 1H and {1H}13C NMR (nuclear magnetic resonance) data from a 600 MHz JEOL ECZR series instrument at 28 °C. Signals were internally referenced against tetramethylsilane. GC (Gas chromatography) data from an Agilent 7890 GC operating in head space injector mode and with a CPSIL 8CB capillary column (30 m × 0.25 mm × 0.25 μm) employed a GC-FID detector. The oven temperature was initially 55 °C and was increased with a rate of 10 °C min-1 up to 230 °C. The temperature of the detector and the injector were 300 °C and 250 °C respectively. For quantitative analysis of the products, methanol (GC/MS grade) was used as an internal standard.

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.

There is an increasing strategic imperative for leading manufactures to rethink their operations, particularly within the context of the sustainable development goals (SDGs), and their environmental, social, and governance (ESG) commitments. Today, ESG performance is a critical component of business strategy, and a source of competitive advantage. From a strategic operations management perspective, an under explored dimension is the role mergers & acquisitions (M&A) plays in enhancing the ESG profile of an organisation, and that of its product supply chain. While outcomes from M&A may produce mixed financial results, the challenges of enhancing post-merger ESG performance is not well understood in the operations management literature, or practically considered during M&A, representing a gap of both theoretical and practical relevance. The objective of this research is to study sustainable supply chains enabled by M&A, by examining motivations, strategic considerations, and integration outcomes from a capabilities perspective. The research question is: How might sustainable supply chain perspectives inform M&A? A multiple case study research approach was adopted, drawing upon eight in-depth product-supply chain M&A transactions within the agri-food and energy sectors. These industries were selected based on their recent volume of M&A activity, and their increasing strategic significance on sustainability. This research contributes to two main streams of sustainable supply chain theory: theory describing supply chain strategies for competitive advantage, and those theories for developing organisational and performance processes for operations sustainability. This thesis contributes five new insights relevant to firms active in M&A, with ambitious sustainable supply chain goals. Firstly, a deal analysis and maturity model framework, integrating key concepts from sustainable supply chain management and the M&A process literature is defined. Secondly, existing merger motives that explain M&A target selection are expanded to include product stewardship, firm ESG performance, and network transformation as sustainable supply chain motivations. Thirdly, this research provides insight into the strategic considerations of relevance by M&A process phase when executing sustainability-targeted M&A. Fourthly, the integration outcomes that are enabled by sustainable supply chain M&A are identified. Finally, propositions for sustainable supply chains are identified that define the relationship between the merger motivations, strategic considerations, and integration outcomes. Together, these form a substantive sustainable supply chain management premise, and a new organisational process perspective for operations sustainability-enabled M&A. This research is of relevance to managerial practitioners in part due to the increasing stakeholder interest in operations sustainability and ESG performance. Industrial sectors and firms with ambitious ‘net-zero’ transition agendas will find the merger motives, strategic considerations, integration outcomes, and resulting operations-sustainability M&A deal archetypes of practical relevance. The four emergent deal archetypes are 1 (passive), 2 (pragmatic), 3 (ideological), and 4 (regenerative). Furthermore, private equity firms and corporate development officers exploring divestment opportunities might utilise this operations-sustainability enabled M&A perspective to inform due diligence and supply chain ESG risk management.

From the British debate on the depletion of coal in 1865 to the First World Power Conference held in London in 1924, scientists, engineers, industrialists, and politicians produced new interpretations of the past, present, and future in terms of the mobilisation of energy resources. This thesis identifies an emerging ‘energy developmentalism’, which called for maximising energy use to maintain or improve a nation’s place in international competition. Energy developmentalism was not a marginal worldview confined to ‘energeticists’, but a coherent set of claims, measurements, and arguments that informed energy governance on an international scale. Rather than focusing on a single resource, energy developmentalism applied a unified schema to all energy sources, including those like solar and tidal energy that were still mostly theoretical. Drawing on sources from across Europe, while staying grounded in political changes in Britain and France, makes it possible to understand how a general formula for transforming raw materials with maximum efficiency was applied differently depending on specific political contexts. This period saw the articulation of problems like the depletion of resources, the difference between renewable and nonrenewable energy, the intermittency of renewables, the overreliance on a single source of energy, and the centrality of energy to modern economies – problems that are often associated with later periods. Scientific measurements of efficiency, horsepower, and kilowatts became operators in political debates centred on questions of national standing and progress. Even as oil became increasingly important in the world economy, the delegates at the First World Power Conference transformed a vision of a renewable energy future into one of a general expansion of energy consumption as the basis of progress. In so doing, they downplayed the continued importance of fossil fuels and equated ‘conservation’ with the fullest possible use of all energy sources, renewable or not.

Coral reefs are at increasing risk of climate-induced mass bleaching events and mass mortality, yet we do not know how coral reef fish species respond to habitat loss on temporal and spatial scales relevant to climate change. The Red Sea represents an ideal model system to address this given that many reef fish populations persisted during the Last Glacial Maximum despite a significant loss of coral reefs. I studied their demogaphic history to determine the impact of environmentally-induced habitat loss. High-throughput sequencing data combined with an Approximate Bayesian Computation framework (including machine learning techniques) provided sufficient power to estimate population parameters for five reef fish species, Dascyllus abudafur, Dascyllus trimaculatus, Dascyllus marginatus, Pomacanthus maculosus, and Carcharhinus melanopterus. The genetic bottleneck experienced during the Last Glacial Maximum (LGM) was not as small as was expected, highlighting the importance of coral reef habitat and refugia. Studying the impact of the LGM on Dascyllus marginatus, a species with a restricted range in the Indian Ocean, enabled me to use this study design to determine that the refugia was unlikely to have been outside the Red Sea, but rather in-situ. The extensiveness of an external population did not appear to affect the response to habitat loss. Lastly, studying the impact of the LGM on Carcharhinus melanopterus, a larger, more motile shark species, showed a similar pattern of response to habitat loss. I then compared the Red Sea barrier with other biogeographic barriers across the Indo-Pacific; in this case it was stronger than some but not as strong as the Indo-Pacific barrier. Overall, the demographic histories showed a similar and mild response to environmentally-induced habitat loss in the Red Sea across species, albeit with some ecological differences. Two case studies allowed me to uncover more about the unique history of the Red Sea, and provided opportunities to discuss other important questions around coral reef refugia and the biogeography of the Indo-Pacific.

AbstractThe production of clean fuels and chemicals from waste feedstocks is an appealing approach towards creating a circular economy. However, waste photoreforming commonly employs particulate photocatalysts, which display low product yields, selectivity, and reusability. Here, a perovskite‐based photoelectrochemical (PEC) device is reported, which produces H2 fuel and simultaneously reforms waste substrates. A novel Cu30Pd70 oxidation catalyst is integrated in the PEC device to generate value‐added products using simulated solar light, achieving 60–90% product selectivity and ≈70–130 µmol cm−2 h−1 product formation rates, which corresponds to 102–104 times higher activity than conventional photoreforming systems. The single‐light absorber device offers versatility in terms of substrate scope, sustaining unassisted photocurrents of 4–9 mA cm−2 for plastic, biomass, and glycerol conversion, in either a two‐compartment or integrated “artificial leaf” configuration. These configurations enable an effective reforming of non‐transparent waste streams and facile device retrieval from the reaction mixture. Accordingly, the presented PEC platform provides a proof‐of‐concept alternative towards photoreforming, approaching more closely the performance and versatility required for commercially viable waste utilization.

Achieving reductions in global anthropogenic emissions necessary to mitigate the worst effects of climate change will require significant reductions in energy demand. However, there are concerns that energy demand reductions involving lifestyle and behavioural changes might negatively impact peoples’ wellbeing. The work in this thesis studies the impacts of how people spend their time – commonly known as time-use – to try to understand whether this is the true, or whether energy demand could be reduced while improving wellbeing. Using the UK as a case study, this issue is examined by determining the energy use and wellbeing attributes of different activities and lifestyles, by modelling the impacts of shifts in time-use between activities, and by comparing the importance of three specific changes that might impact future energy use and wellbeing. Firstly, based upon existing literature it is identified that there is a need to better understand the combined energy and wellbeing impacts of different activities and lifestyles. Combining UK time-use and energy consumption data, the energy intensity, enjoyment and sociability of time is studied. Comparing these metrics for different activities suggests that since the most enjoyable (and in some cases sociable) activities are generally the least energy-intensive, acceptable (or popular) lifestyle changes might exist that reduce national energy use and improve wellbeing. However, studying changes between 2000 and 2015 shows that while the population’s time became less energy-intensive, there was little change in average enjoyment and a reduction in sociability. Segmenting the population by age reveals that an ageing population could present a challenge since energy use broadly increases with age-group while social contact reduces. However, comparing occupations highlights opportunities for specific actions that could improve wellbeing and reduce energy use, while regional differences suggest that wellbeing might be improved without increasing energy use. Having determined the energy intensity and wellbeing associated with different uses of time, the impacts of possible time-use changes are then studied. Acknowledging the difficulty in trying to predict how people might choose to re-allocate time in different situations, a sensitivity-based approach is used to study the impacts of a wide range of possible shifts in time between activities. The approach is then applied to explore the impacts of extreme lifestyle changes associated with COVID-19 lockdown measures in the UK and validated against real-world observations during the pandemic. While activity changes associated with lockdown measures reduce energy use, there are varying implications for peoples’ wellbeing, with the youngest appearing to be most negatively impacted but those able to work from home potentially benefiting. Although lockdown measures prevented some of the most enjoyable and sociable activities from happening, alternative activity changes could be supported in future that reduce energy use while improving wellbeing. Finally, time is used as a basis to compare the importance of different types of changes and help to prioritise actions. This is demonstrated by studying the combined impacts of three example changes – greater home working, changes in commuting transport modes and car intensity – on office workers’ energy use and wellbeing. The results show that working from home could have a greater impact upon office workers’ average energy use and enjoyment than changes to commuting modes, but that the social contact provided by the office could be difficult to replace. The study also demonstrates different ways that energy savings might be achieved through home working, shifts in commuting modes and changes to vehicle intensity. This approach could be used more widely to compare a broader range of changes, understand their interactions and different ways to achieve outcomes, and help to identify those changes that are most important to reduce energy use and improve wellbeing. The work presented in this thesis shows that time-use can be used as a basis to examine energy demand and wellbeing together. Using time-use to link these issues enables trade-offs or co-benefits due to different uses of time to be determined and allows rebound effects to be considered. The results suggest that reducing energy use can be achieved at the same time as improving wellbeing. The hope is that the approaches and findings presented in this thesis can provide a basis for wider discussion and a platform for future work to support climate change mitigation strategies that are positive for both the environment and society.

In this essay, I offer some reflections on the possible futures of the idea of climate change. How might people in, say, the year 2067 be thinking about climate change? What might the idea of climate change signify for them in terms of daily living, creative practice, religious belief, technological innovation and political action? This is very different question than asking climate scientists ‘What will the global temperature or the level of the ocean be in 2067?’ We can state with some confidence that in 2067 physical climates around the world will be warmer than they are now, there will be less ice on the planet and the ocean level will be higher. Of this much science can be certain. More tentatively, a range of environmental changes that may follow from this warming - and some possible social impacts - can be sketched. But this is not the same as predicting how people in 2067 will be thinking about climate change. The research assessed by the IPCC doesn’t help us understand how the idea of climate change will evolve. So how does one write about the future of an idea? It is hard to explain the future of an idea when the very notion of ‘the future’ itself has a past and a future (Bowler, 2017). Yet there seems no shortage of ideas for which their future has been written - for example, the ideas of progress, democracy, science, socialism, capitalism, intelligence, being human. The list is long. Let me suggest three broad framings of the idea of climate change which might help us imagine some of its possible future trajectories.

AbstractWith the global economy not yet 10% circular, businesses are key stakeholders in designing new forms of resource use, especially large multinationals. However, compared with the wealth of studies on ‘born sustainable’ start‐ups, there is minimal case study or interview based research into how incumbent companies are approaching this transition. Focusing on plastics, we ask: how does one incumbent multinational company approach the circular economy transition? This paper presents a case study of the incumbent multinational chemical company Dow, a leading plastics manufacturer. Varied external stressors and drivers for the circular economy act upon a company (which also has its own imperatives), resulting in tentative steps towards circular economy. To date, these steps have tweaked the existing system rather than radically altering the business model. For companies, like for the entire global economy, this transition has only just begun. This paper identifies key drivers, enablers and barriers of the circular economy, none of which are fixed or immutable. Knowing which levers for change are available and effective could help policy makers to shift gear to enable quicker progress towards circularity. Overall, broad based support and engagement is needed to progress the circular economy, hence all stakeholders have roles to play in demanding and enacting circular practices. Funder: Philanthropic donation to the University of Cambridge Institute for Sustainability Leadership from Unilever Funder: Prince of Wales Fellowship in Pathways to a Circular Economy