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Abstract: X-ray cavity quantum optics with inner-shell transitions has been limited by the spectral overlap between resonant and continuum states. Here, we report the first experimental demonstration of cavity-controlled core-to-core resonant inelastic x-ray scattering (RIXS). We suppress the absorption-edge effects by monitoring the RIXS profile, thereby resolving the resonant state from the overlapping continuum. We observe distinct cavity-induced energy shifts and cavity-enhanced decay rates in the 2⁢𝑝⁢3⁢𝑑 RIXS spectra of WSi2. These effects, manifesting as stretched or shifted profiles in the RIXS planes, enable novel spectroscopic applications via cavity-controlled core-hole states. Our results establish core-to-core RIXS as a powerful tool to manipulate inner-shell dynamics in x-ray cavities, offering new avenues for integrating quantum optical effects with x-ray spectroscopy.

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Abstract: This paper demonstrates a new approach that exploits both lattice strain mapping via Wide Angle X-ray Scattering (WAXS) and Digital Volume Correlation (DVC) of Computed Tomography (CT) to understand the material response at different length scales in Carbon Fibre Reinforced Polymers (CFRPs) under in-situ loading, a phenomenon of substantial importance for the modelling, design, and certification of composite structures. WAXS gives insight into fibre lattice strain, while DVC provides sub-laminate response in the CFRP. A detailed numerical simulation was also developed to compare with these novel experimental methods. This approach is the first demonstration that the strain within the crystalline regions of the fibre is distinct from the sub-laminate behaviour, with up to 80 % and 36 % differences in the longitudinal and transverse directions, respectively, as a result of the complex microstructure of the fibres. An improved understanding of composite behaviour is fundamental to understanding how strain accommodation leads to structural failure, providing routes to refine part rejection criteria and reduce the environmental impact of this increasingly widespread material class.

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Abstract: Our bone health as an adult is defined by patterns of development in early life, with perturbed growth during fetal and neonatal periods predisposing individuals to poor bone health in adulthood. Studies have identified poor maternal diet during pregnancy as a critical factor in shaping offspring bone development, with significant impacts on adult bone structure and health. However, the association between a father’s diet and the bone health of his offspring remains poorly defined. To address this knowledge gap, we fed male C57BL/6 mice either a control normal protein diet (NPD; 18% protein) or an isocaloric low protein diet (LPD; 9% protein) for a minimum of 8 weeks. Using these males, we generated offspring through artificial insemination, in combination with vasectomised male mating. Using this approach, we derived offspring from either NPD or LPD sperm but in the presence of NPD or LPD seminal plasma. Using micro-computed tomography and synchrotron X-ray diffraction, we observed significant changes in offspring femur morphology and hydroxyapatite crystallographic parameters from just 3 weeks of age in offspring derived from LPD sperm or seminal plasma. We also observed that differential femur morphology and hydroxyapatite crystallographic parameters were maintained into adulthood and into a second generation. Analysis of paternal sperm identified a down regulation of 26 osteogenic genes associated with extracellular matrix levels and maintenance, transcription and growth factors and bone ossification. These observations indicate that poor paternal diet at the time of conception affects offspring bone development and morphology in an age and generation specific manner.

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Abstract: This study presents the first demonstration of the use of X-ray diffraction (XRD) to quantify the radial or transverse deformation in Hexcel IM7 PolyAcryloNitrile (PAN)-based carbon fibres at temperatures as low as 200 K (-70 °C). The Coefficient of Thermal Expansion (CTE) is a critical design parameter that needs to be precisely quantified for the next generation of carbon fibre-based Liquid Hydrogen ( ) storage tanks for net-zero aviation. This variable quantitatively describes the thermal mismatch between the fibre and the resin that is the driver for microcracking and tank leakage. However, quantification of the CTE of the fibres is experimentally challenging. The results provide unique insights, indicating that the microscopic transverse CTE of the fibre ( ) is equal to 26.2 × 10-6 K-1 and is governed by van der Waals forces, similar to those in the basal c-axis (out-of-plane) direction of graphite and the radial direction of multi-wall carbon nanotubes. Taking into account the microcrack-induced relaxation effect reported in polycrystalline graphite, the macroscopic fibre transverse CTE was determined to be 7.86 × 10-6 K-1. XRD data were also collected on Hexcel IM7/8552 Uni-directional (UD) and Quasi-isotropic (QI) composite laminates to investigate the influence of the interaction of the resin matrix with the fibre lattice and the stacking sequence on the development of thermal fibre lattice strain. In the UD laminate, the presence of resin induces an additional transverse strain in the fibres as a result of resin contraction during cooling, leading to the development of a compressive strain in the fibre direction. This behaviour was found to be in good agreement with numerical simulations, with a 13 % error at the lowest measured temperature. In contrast, the fibres in the QI configuration were reinforced in the transverse direction, effectively mitigating the influence of resin contraction. These CTE values, insights, and resulting models are essential for multi-scale modelling, design and certification of carbon fibre composite tanks that are required to achieve net-zero aviation.

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Abstract: In this project sensitivity mapping using a source of focused X-ray microbeam was performed on three fabricated samples (VS-Pt, HPS-Pt and HPS-Al/Pt). The VS-Pt sample was chosen due to its special features such as thin nitrogen lines and substrate area. The source of focused X-ray beam (from synchrotron micro-beam called Diamond Light Source, DLS) was investigated in order to choose the optimum conditions to obtain high resolution images of the nitrogen lines within the sample. Additionally the sensitivity mapping of HPS-Pt and HPS-Al/Pt was investigated to study the effect of beam size, step displacement, bias polarity, annealing, and electrical contact were studied on the homogeneity of current response in order to choose optimum conditions for synchrotron measurements. High spatial resolution maps obtained for VS-Pt sample with a micro step displacement of 10 μm or less. Photocurrent is affected by bias polarity; current at negative bias is higher than at positive bias. There are regions with high current thus taking more time to restore to baseline value. Time rises slowly near nitrogen line with stabilization time increasing with bias. For HPS-Al/Pt, as bias increases, homogeneity of current response does not improve. At different negative biases, HPS-Al/Pt exhibits high dark current, unstable signals, and very low photocurrent. For HPS-Pt, at a bias of +50 and –50 V, current response is uniform becoming more homogenous at 100 V, and improving further as the bias increases up to +200 V; making it the most suitable choice for synchrotron measurements.