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Characterisation of Vandenbrandeite: A Potential Alteration Product of Spent Nuclear Fuel
No full textThe use of copper canisters in the Swedish KBS-3 concept for spent nuclear fuel disposal could result in the formation of copper-bearing uranyl phases should a canister suffer from defects or if the containment were to fail before reducing conditions are established in the repository. Most uranyl species would be expected to display higher solubility than the original uranium(IV) dioxide fuel, leading to enhanced release, though this would depend on the phase and prevailing groundwater conditions. Secondary alteration products may also be poorly crystalline or even amorphous, making characterisation difficult during the pre-closure period owing to the high radiation field close to the canister. Vandenbrandeite, (CuUO2(OH)4), is a rare mineral in nature but known to form by alteration of primary uraninite through interaction with oxidising groundwater containing dissolved copper Consequently, an attempt has been made to characterise two vandenbrandeite specimens of varying crystallinity by luminescence and multiple-laser Raman spectroscopy; techniques amenable to remote, robotic deployment and which have proved useful in discriminating other uranyl oxy-hydroxides, silicates and phosphates. The first reported luminescence emission and excitation spectra for vandenbrandeite revealed near-negligible luminescence, with a slightly enhanced signal for the specimen displaying poorer crystallinity. This observation agrees well with density functional theory calculations. The simulated projected density of state and band structure show an unlikely transition from the U f-orbitals to Cu d-orbitals, or O states, would be required for luminescence to be detectable; this probably improves for poorly crystalline specimens as the spatial overlap between the orbitals increases. Further, negligible differences in the number of peaks and peak positions were detected in the laser wavelength-dependent Raman spectra although again, variation in background noise and peak shape was observed based on the degree of crystallinity. Good agreement was obtained between experimental and simulated Raman spectra, particularly with the environmentally sensitive axial uranyl stretching modes, validating the crystal system derived in this study. The findings of this study suggest luminescence spectroscopy, when combined with Raman spectroscopy, may be able to both identify vandenbrandeite and distinguish between crystalline and amorphous forms based on their relative luminescence intensity
Circular production and maintenance of automotive parts: An Internet of Things (IoT) data framework and practice review
Get PDF•The paper focuses on the matching of digital technologies to maintenance practice in the automotive sector.•A framework for IOT enabled circular maintenance practice and treatment of automotive parts is proposed.•The framework proposed is capable of processing data from vehicle based sensors.•An Auto-circular simulator concept is outlined, providing visualisation and analytics toolbox capabilities.•A case study focused on a hydrogen car power unit is included, with a supporting ontology.The adoption of the Circular Economy paradigm by industry leads to increased responsibility of manufacturing to ensure a holistic awareness of the environmental impact of its operations. In mitigating negative effects in the environment, current maintenance practice must be considered for its potential contribution to a more sustainable lifecycle for the manufacturing operation, its products and related services. Focusing on the matching of digital technologies to maintenance practice in the automotive sector, this paper outlines a framework for organisations pursuing the integration of environmentally aware solutions in their production systems. This research sets out an agenda and framework for digital maintenance practice within the Circular Economy and the utilisation of Industry 4.0 technologies for this purpose
Demographic and psychological predictors of community pharmacists’ cancer-related conversations with patients: a cross-sectional analysis and survey study.
Get PDFBackgroundThere is increasing interest in the role of community pharmacy in the early diagnosis and prevention of cancer. This study set out to examine how often community pharmacists (CPs) encourage patients to spot or respond to potential signs and symptoms of cancer, and how often they help people to make an informed decision about taking part in bowel cancer screening.MethodsData from 400 UK CPs, who completed the 2018 Cancer Research UK Healthcare Professional Tracker, were analysed. The primary outcomes were: ‘how often CPs encourage patients to spot or respond to potential signs and symptoms of cancer’ and ‘how often CPs encourage eligible people to make an informed decision to participate in bowel cancer screening’. Associations between behaviours and demographic and psychological variables (Capability, Opportunity and Motivation) were assessed using multivariate logistic regression.ResultsMost (n=331, 82.8%) CPs reported occasionally, frequently or always encouraging patients to spot or respond to potential signs and symptoms of cancer, while only half (n=203, 50.8%) reported occasionally, frequently or always helping people make an informed decision to participate in bowel cancer screening. Female sex (aOR: 3.20, 95%CI: 1.51, 6.81; p<0.01) and increased Opportunity (aOR: 1.72, 95%CIs: 1.12, 2.64; p<0.05) and Motivation (aOR: 1.76, 95%CIs: 1.37, 2.27; p<0.001) were associated with encouraging patients to spot or respond to potential signs and symptoms of cancer; all three psychological variables were associated with helping people to make an informed decision to participate in bowel cancer screening (Capability: aOR: 1.39, 95%CIs: 1.26, 1.52, p<0.001; Opportunity: aOR: 1.44, 95%CIs: 1.11, 1.87; p<0.01; Motivation: aOR: 1.45, 95%CIs: 1.05, 2.00; p<0.05).ConclusionsMost CPs encourage patients to spot or respond to potential cancer symptoms, while only half help them make an informed decision to participate in bowel cancer screening. A multifaceted approach, targeting multiple COM-B components, is required to change these behaviours
Practical approaches to labelling terminal alkynes with deuterium
No full textBase catalysed exchange with sodium hydroxide, calcium oxide or N,N,N,N-tetramethylguanidine in deuterium oxide is a viable procedure for the preparation of terminally deuterated alkynes for those alkynes stable to strong base. The use of silver perchlorate as a catalyst is an alternative practical option when labelling alkynes which are sensitive to base or contain functionalities which would lead to labelling elsewhere in the molecule. Labelling with this catalyst takes place smoothly at ambient temperature in a mixture of N,N-dimethylformamide and deuterium oxide
Coherence dynamics in low-energy nuclear fusion
Get PDFLow-energy nuclear fusion reactions have been described using a dynami-cal coupled-channels density matrix method, based on the theory of open quantum systems. For the first time, this has been combined with an energy projection method, permitting the calculation of energy resolved fusion probabilities. The results are benchmarked against calculations using stationary Schrödinger dynamics and show excellent agreement. Calculations of entropy, energy dissipation and coherence were conducted, demonstrating the capability of this method. It is evident that the presence of quantum decoherence does not affect fusion probability. This framework provides a basis for quantum thermodynamic studies using thermal environments
Gracious Growth: How to Manage the Trade-off between Corporate Greening and Corporate Growth
Get PDFOrganizations are increasingly turning to sustainable practices. A significant challenge in the endeavour to embrace sustainability relates to the trade-off between corporate greening and corporate growth – i.e., the difficult task of achieving growth while being truly sustainable. Through an in-depth study of Brunello Cucinelli, one of the world’s leading companies in the luxury fashion industry, we introduce the management philosophy of “gracious growth” to help organizations manage the green-growth trade-off and pursue substantial rather than symbolic sustainability. We offer actionable recommendations and present a process framework that organizations can adopt to implement “gracious growth”. Generating new insights about how growth and sustainability can be simultaneously achieved, this article provides ideas that can help managers enhance their organizations’ economic and environmental performance while also avoiding the legitimacy risks associated with greenwashing
On local kirigami mechanics II: Stretchable creased solutions
Get PDFFollowing on Part I of this work series on local kirigami mechanics, we presenta study of a discretely creased mechanism as a model to investigate themechanics of the basic geometric building block of kirigami - the e-cone. Weconsider an annular disk with a single radial slit discritised by a series of radialcreases connecting kinematically flat rigid panels. The creases allow bothrelative rotation and separation between panels, capturing both bending andstretching deformations. Admissible equilibrium congurations are obtainedby penalising these deformations using elastic springs with stiffnesses derivedfrom compatible continuum plate deformations. This provides a tool to studyboth inextensible and extensible e-cone congurations due to opening of theslit and rotation of its lips. This creased model hence offers the possibilityto study the e-cone away from its isometric limit, i.e., for plates with finitethickness, and explore the full range of post-buckling (far-from-threshold)behaviour as well as initial buckling (near-threshold) instability. Our localapproach provides a fundamental understanding of kirigami phenomenology,underpinned by a proper theoretical approach to geometry and mechanics
Between multiple identities and values: Professionals' identity conflicts in ethically-charged situations
No full textWide-Incidence Angle and Polarisation Insensitive Transparent Metasurface for 5G Outdoor to Indoor Coverage Enhancement
Get PDF—A wide-incident angle and polarisation insensitive transparent metasurface is presented for 5G outdoor to indoor coverage enhancement. In order to predict the structural geometry of the unit cell, the Genetic Algorithm (GA) has been applied. The proposed unit cell is arranged in a periodic structure to construct the transmission surface consisting of tow transparent layers of Indium Tin Oxide (ITO) mounted on both sides of Polyethylene Terephthalate (PET) substrate. The proposed transmission metasurface can be simply coated on a glassy windows to empower the outdoor to indoor 5G signals
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