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Roadmap for a sustainable circular economy in lithium-ion and future battery technologies
Get PDFFunding: The authors would like to acknowledge the funding from the UK's Faraday Institution supporting the Recycling of Lithium-ion Batteries (ReLiB: FIRG005, FIRG027 & FIRG057) and Science of Battery Safety (SafeBatt) projects. The authors would like to thank the Faraday Institution ReLiB project (Grant codes FIRG005, FIRG027 and FIRG057) and the UKRI Interdisciplinary Circular Economy Centre for Technology Metals (TechMet) Grant No. EP/V011855/1 for funding. The authors would like to thank the Faraday Institution ReLiB project (Grant Codes FIRG005, FIRG027 and FIRG057) and the UKRI Interdisciplinary Circular Economy Centre for Technology Metals (TechMet) Grant No. EP/V011855/1 for funding. The authors would like to thank the following funding bodies who have supported this work: the Faraday Institution's ReLiB (FIRG005, FIRG027 and FIRG057), and CATMAT (FIRG016) grants. This work was carried out with funding from the Faraday Institution (faraday.acuk; EP/S003053/1), Grant Number FIRG025. Funding TREFCOP/W019167/1 (GH, PAA, JB) ReLiB EK, ED, PAA FIRG005, FIRG027 & FIRG057, EK acknowledges SIMBA, which has received funding from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 883753. The authors would like to acknowledge the funding from the UKRI Interdisciplinary Circular Economy Centre for Technology Metals (Met4Tech) Grant No. EP/V011855/1.The market dynamics, and their impact on a future circular economy for lithium-ion batteries (LIB), are presented in this roadmap, with safety as an integral consideration throughout the life cycle. At the point of end-of-life (EOL), there is a range of potential options—remanufacturing, reuse and recycling. Diagnostics play a significant role in evaluating the state-of-health and condition of batteries, and improvements to diagnostic techniques are evaluated. At present, manual disassembly dominates EOL disposal, however, given the volumes of future batteries that are to be anticipated, automated approaches to the dismantling of EOL battery packs will be key. The first stage in recycling after the removal of the cells is the initial cell-breaking or opening step. Approaches to this are reviewed, contrasting shredding and cell disassembly as two alternative approaches. Design for recycling is one approach that could assist in easier disassembly of cells, and new approaches to cell design that could enable the circular economy of LIBs are reviewed. After disassembly, subsequent separation of the black mass is performed before further concentration of components. There are a plethora of alternative approaches for recovering materials; this roadmap sets out the future directions for a range of approaches including pyrometallurgy, hydrometallurgy, short-loop, direct, and the biological recovery of LIB materials. Furthermore, anode, lithium, electrolyte, binder and plastics recovery are considered in order to maximise the proportion of materials recovered, minimise waste and point the way towards zero-waste recycling. The life-cycle implications of a circular economy are discussed considering the overall system of LIB recycling, and also directly investigating the different recycling methods. The legal and regulatory perspectives are also considered. Finally, with a view to the future, approaches for next-generation battery chemistries and recycling are evaluated, identifying gaps for research. This review takes the form of a series of short reviews, with each section written independently by a diverse international authorship of experts on the topic. Collectively, these reviews form a comprehensive picture of the current state of the art in LIB recycling, and how these technologies are expected to develop in the future.Peer reviewe
Solid-state confinement effects in selective exo-H/D exchange in the rhodium σ-norbornane complex [(Cy2PCH2CH2PCy2)Rh(η2:η2-C7H12)][BArF4]
Get PDFFunding: The authors acknowledge the EPSRC for funding through awards EP/K035908/1, EP/K035681/1 and EP/M024210/1.Density functional theory calculations modelling selective exo-H/D exchange observed in the Rh σ-alkane complex [(Cy2PCH2CH2PCy2)Rh(η2:η2-endo-NBA)][BArF4], [1-NBA][BArF4] , are reported, where ArF=3,5-C6H3(CF3)2 and NBA=norbornane, C7H12. Two models were considered 1) an isolated molecular cation, [1-NBA]+ and 2) a full model in which [1-NBA][BArF4] is treated in the solid state through periodic DFT. After an initial endo-exo rearrangement, both models predict H/D exchange to proceed through D2 addition and oxidative cleavage followed by a rate-limiting C−H activation of the norbornane through a σ-CAM step to form a [1-Rh(D)(η2-HD)(norbornyl)]+ intermediate. HD rotation followed by a σ-CAM C−D bond formation, HD reductive coupling and HD loss then complete the H/D exchange process. exo-H/D exchange is facilitated by a supporting agostic interaction and is consistently more accessible kinetically than the potentially competing endo-H/D exchange (isolated cation: ΔG≠exo = +15.9 kcal/mol, ΔG≠endo = +18.4 kcal/mol; solid state: ΔG≠exo = +22.1 kcal/mol, ΔG≠endo = +25.1 kcal/mol). The solid-state environment has a significant impact on the computed energetics, with barriers increasing by ca. 7 kcal/mol, while only the solid-state model correctly predicts the endo-bound NBA complex to be the resting state of the system. These outcomes reflect solid-state confinement effects within the pocket occupied by the [1-NBA]+ cation and defined by the pseudo-octahedral array of neighbouring [BArF4]− anions. The asymmetry of the solid-state environment also requires a second H/D exchange pathway to be defined to account for reaction at all four exo-C−H bonds. These entail slightly higher barriers (ΔG≠exo = +24.8 kcal/mol, ΔG≠endo = +27.5 kcal/mol) but retain a distinct preference for exo- over endo-H/D exchange.Peer reviewe
Machine learning driven design and fabrication of photonic devices with engineered dispersion
Get PDFThis thesis combines optical physics and advanced machine learning to tackle challenges in thin film and waveguide design. By engineering material dispersion and optimizing optical systems, it bridges traditional physics methods with modern data-driven strategies, using simulations and artificial intelligence to enhance the design of complex optical structures.
Initially, a Python Transfer Matrix Method (TMM) is developed to simulate and validate the optical properties of Distributed Bragg Reflectors, bandpass filters, and Epsilon-Near-Zero materials. Planar disordered waveguides are introduced to study random scattering and Kerr effects in both linear and nonlinear regimes, with Finite-Difference Time-Domain simulations generating comprehensive datasets for machine learning model training.
Various neural network architectures—Multilayer Perceptrons, Convolutional Neural Networks, and Transformers—are explored to recognize patterns in ultrafast laser characterization, thin film stacking, and disordered waveguides. The thesis then applies Reinforcement Learning (RL) to optical design problems, illustrating fundamental RL concepts through a custom maze game and using advanced algorithms for optimization tasks.
Experimental results examine ENZ apertures made of thin silver and silica layers, forming anisotropic effective media with enhanced transmission. Ultrafast laser characterization with neural networks improves the accuracy of Second- and Third-Harmonic Generation measurements, reducing the need for repetitive experiments.
A multi-agent RL system is developed for the inverse design of thin films, optimizing parameters, material selection, and layer thickness. A novel reward function employing polynomial control allows tailored spectral responses, while regional constraints and penalties for unwanted features improve filter and reflector designs.
In disordered waveguide design, Generative Adversarial Networks are used for inverse design tasks. Three architectures are evaluated for generating waveguide geometries based on desired optical responses, addressing the complexities of sparse and disordered systems.
Finally, Large Language Model integrates with the RL-TMM framework using Retrieval-Augmented Generation, enhancing the system's reasoning and prediction capabilities for optical responses."This work was supported by the self-funding first year, and the Chinese Scholarship Council for three years funding [grant number. 202108060233]."--Fundin
In-utero exposure to PM2.5 and adverse birth outcomes in India : geostatistical modelling using remote sensing and demographic health survey data 2019–21
Get PDFThis study investigates the influence of air quality on birth weight and preterm birth. Utilizing data from the national family health survey and raster images, the study employs various statistical analyses and spatial models to elucidate the connection between in-utero exposure to air pollution and birth outcomes, both at the individual and district levels. It was observed that approximately 13% of children were born prematurely, and 17% were born with low birth weight. Increased ambient particulate matter 2.5 concentrations during pregnancy were associated with higher odds of low birth weight (AOR: 1.4; 95% CI: 1.29–1.45). Mothers exposed to particulate matter 2.5 during pregnancy had a heightened likelihood of delivering prematurely (AOR: 1.7; 95% CI: 1.57–1.77) in comparison to unexposed mothers. Climatic factors such as rainfall and temperature had a greater association with adverse birth outcomes. Children residing in the Northern districts of India appeared to be more susceptible to the adverse effects of ambient air pollution. Employing a distributed spline approach, the study identified a discernible upward trend in the risk of adverse birth outcomes as the level of exposure increased, particularly following an exposure level of 40 particulate matter 2.5 ug/m3. A 10 μg m − 3 increase in particulate matter 2.5 exposure was associated with a 5% increase in the prevalence of low birth weight and a 12% increase in preterm birth. Among the different spatial models used in this study, the multiscale geographically weighted regression spatial model showed the best fit to the actual scenario, effectively capturing the spatial relationships between particulate matter 2.5 exposure and adverse birth outcomes. In addition to addressing immediate determinants such as nutrition and maternal healthcare, it is imperative to collaboratively address distal factors encompassing both indoor and outdoor pollution to attain lasting enhancements in child health.Peer reviewe
Fast mapping in hominids
Get PDFFunding: This research was supported by funding from the Institute of Speech and Language Therapy (K.S.), the University of Neuchâtel (K.S., K.Z.) and the National Centre for Competence in Research ‘Evolving Language’ (SNSF agreement 295 number 51NF40_180888, K.Z.) and Top-Up Grant (grant number N603-18-01, V.A.D.W., K.Z.).Fast mapping is essential when children acquire language, but whether the required cognition is uniquely human or shared with animals is debated. Although documented in dogs and cats, both species have a history of domestication of social cognition, so that it remains unclear whether fast mapping is naturally present in non-domesticated animals. Here, we used an eye-tracking paradigm to test three species of hominids – gorillas, orangutans and humans – in their ability to rapidly learn to associate novel sounds with objects in their everyday noisy environment. The task was difficult for all participants, but while adult humans showed evidence of fast mapping, we could not detect any sign of learning in the other hominids. These species differences could have trivial causes, such as problems with attention or motivation, but it is also possible that fast mapping requires a preexisting lexicon before becoming an effective learning mechanism, or that it has simply evolved after the shared ancestor of all great apes.Peer reviewe
The profits of personality : advancing the fourth 'I’ in international political economy research
Get PDFTwo decades after Hay’s classification of political economy research, not much has changed. Interests, institutions, and ideas continue to dominate, especially in international political economy (IPE) scholarship. Despite calls for more actor-centred and psychological approaches, the individual remains a missing ‘I’ in most IPE research. This paper advances the fourth ‘I’ in IPE by drawing on psychological work in foreign policy analysis (FPA) and demonstrating the utility of personality analysis in accounting for ways that political leaders manage integrated national economies. We use corporate taxation and tax competition as our illustrative case study, focusing in particular on the different ways leaders in Ecuador and Peru responded to windfall profits during the 2003-2013 commodities boom. We argue that interests, institutions, and ideas do not completely account for variation in the taxation of windfall profits in these countries and we employ leadership trait analyses of Presidents Correa and Humala to provide the missing link. Our results suggest personality differences, when combined with contextualised understandings of the pressures that leaders face, best explain their different approaches. Overall, the paper points to the profits of including personality in IPE and forges stronger links between IPE and FPA research.Peer reviewe
From landlocked to landlinked, on its own termsconnectivity and mega-projects in Turkmenistan
No full textFunding: Italian Ministry for Education, Universities and Research (MIUR).This article examines the concept of the mega-project as a lens through which to explore the connectivity strategies of Turkmenistan, a Central Asian republic often portrayed as remote and isolated. Despite its landlocked geography and a cautious foreign policy grounded in permanent neutrality, Turkmenistan has launched a series of large-scale infrastructural initiatives aimed at enhancing its integration into global networks. While the country lacks the geopolitical leverage of other post-Soviet states such as Azerbaijan or Kazakhstan, Turkmenistan has pursued a tous azimuts strategy, seeking to capitalize on all available economic opportunities. Ashgabat foreign policy is closely tied to the imperative of exporting natural gas, the cornerstone of its national economy. Surrounded by landlocked or unstable neighbors, and competing with regional energy powers like Iran and Russia, the country is compelled to explore new routes and markets. In recent years, Turkmenistan has initiated several ambitious projects—some completed, others still in the planning stage—demonstrating a clear intention to overcome structural constraints through infrastructure-led development.Peer reviewe
Behavioural interventions to increase uptake of FIT colorectal screening in Scotland (TEMPO) : a nationwide, eight-arm, factorial, randomised controlled trial
Get PDFFunding: Scottish Government and Cancer Research UK.Background: Uptake of colorectal cancer screening is suboptimal. The TEMPO trial evaluated the impact of two evidence-based, theory-informed, and co-designed behavioural interventions on uptake of faecal immunochemical test (FIT) colorectal screening. Methods: TEMPO was a 2 × 4 factorial, eight-arm, randomised controlled trial embedded in the nationwide Scottish Bowel Screening Programme. All 40 000 consecutive adults (aged 50-74 years) eligible for colorectal screening were allocated to one of eight groups using block randomisation: (1) standard invitation; (2) 1-week suggested FIT return deadline; (3) 2-week deadline; (4) 4-week deadline; (5) problem-solving planning tool (no deadline); (6) planning tool plus 1-week deadline; (7) planning tool plus 2-week deadline; (8) planning tool plus 4-week deadline. The primary outcome was the proportion of FITs returned correctly completed to be tested by the colorectal screening laboratory providing a positive or negative result, within 3 months of the FIT being mailed to a person. The trial is registered with clinicaltrials.gov, NCT05408169. FINDINGS: From June 19 to July 3, 2022, 5000 participants were randomly assigned per group, with no loss to follow-up. 266 participants met the exclusion criteria; 39 734 (19 909 [50·1%] female and 19 825 [49·9%] male; mean age 61·2 [SD 7·3] years) were included in the analysis. The control group (no deadline, and no planning tool) had a 3-month FIT return rate of 66·0% (3275 of 4965). The highest return rate was seen with a 2-week deadline without the planning tool (3376 [68·0%] of 4964; difference vs control of 2·0% [95% CI 0·2 to 3·9]). The lowest return rate was seen when the planning tool was given without a deadline (3134 [63·2%] of 4958; difference vs control of -2·8% [-4·7 to -0·8]). The primary analysis, assuming independent effects of the two interventions, suggested a clear positive effect of giving a deadline (adjusted odds ratio [aOR] 1·13 [1·08 to 1·19]; p<0·0001), and no effect for use of a planning tool (aOR 0·98 [0·94 to 1·02]; p=0·34), though this was complicated by an interaction between the two interventions (pinteraction=0·0041); among those who were given a deadline, there was no evidence that receiving a planning tool had any effect (aOR 1·02 [0·97 to 1·07]; p=0·53), but in the absence of a deadline, giving the planning tool appeared detrimental (aOR 0·88 [0·81 to 0·96]; p=0·0030). In the absence of the planning tool, there was little evidence that the use of a deadline had any effect on return rates at 3 months. However, secondary analyses indicated that the use of deadlines boosted earlier return rates (within 1, 2, and 4 weeks, particularly around the time of the deadline), and reduced the need to issue a reminder letter after 6 weeks, with no evidence that the planning tool had any positive impact, and without evidence of interactions between interventions. Interpretation: Adding a single sentence suggesting a deadline for FIT return in the invitation letter to FIT colorectal screening resulted in more timely FIT return and reduced the need to issue reminder letters. This is a highly cost-effective intervention that could be easily implemented in routine practice. A planning tool had no positive effect on FIT return.Peer reviewe
Central Asian regionalism in the 1990s : order, familiarisation, and spotlighting
Get PDFFunding: The Royal Society of Edinburgh (2905).In the 1990s, the newly independent Central Asian republics of Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan set up different regional organisations such as the Central Asian Union (1994–1998) and the Central Asian Economic Community (1998–2001) to foster integration in the area. As these organizations did not lead to integration and were eventually disbanded, existing analyses often dismiss them as a failure. Against this backdrop, this paper argues that the notion of failure derives from a specific Eurocentric interpretation of regionalism, which prioritizes integrationist liberal policies over other complex political dynamics of coexistence and order-making. By adopting an English School framework of analysis and by relying on archival materials as well as elite interviews from across the region, the paper demonstrates that those regionalist experiences in Central Asia played three fundamental functions: the re-creation of a regional order after the collapse of the Soviet Union; the familiarization with the diplomatic and legal tools of international politics; and the positioning of Central Asia on the global map through summitry. Early Central Asian regionalism should thus be interpreted as a difficult process of re-creation of order, where pluralist logics of coexistence and independence interacted in tension with solidarist aspirations for unity.Peer reviewe
The persistence and pervasiveness of racial discrimination in Great Britain : capturing experienced racial discrimination over time and life domains
Get PDFFunding: This work was supported by Economic and Social Research Council [grant numbers ES/V013475/1 and ES/W000849/1].Racism has been long-established to be associated with social, economic, and health inequalities for minoritised ethnic groups, but existent evidence likely under-estimates the extent and persistence of experienced racial discrimination due to limitations in the measurement of timing and domains of life where racial discrimination occurs. We analysed data captured by a novel retrospective measure of life course experiences of racial discrimination that measures the extent, persistence, and accumulation of experienced racial discrimination over the life course. Our findings show higher levels of experienced racial discrimination than previously reported, and uncover the pervasiveness of racial discrimination across life domains. By asking about different time periods we find that people who report experiencing racial discrimination are likely to have had these experiences in multiple domains, and multiple time periods, documenting the insidiousness of racial discrimination over time and domains of people’s lives.Peer reviewe
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