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Neutron Capture Therapy (NCT) for cancer treatment is experiencing renewed interest due to advancements in accelerator-based neutron beams, treatment planning software, and patient positioning devices. This study presents the adaptation of an existing neutron radiography beamline (Dingo), at the OPAL research nuclear reactor, for radiobiological research and novel neutron capture agent development. Human glioblastoma cell cultures were irradiated for up to 10 min with a flux of 2.57 × 10 8 n/cm 2 s (± 2.73 × 10 7 ) and the resulting impact was quantified by assessing DNA damage by both immunocytochemistry and flow cytometry. This low cost methodology extends the capability of an existing beamline to allow the development of novel neutron capture agents and study of neutron radiobiological mechanisms. Increasing availability of neutron sources for biological study in this fashion will accelerate the development of NCT for disease specific clinical application.

This study explores the development of a novel composite coating system combining the high hardness of WC and thermal conductivity of Cu, employing the plasma transfer arc welding method under ambient conditions. Utilizing an advanced welding approach, the work investigates microstructural evolution and phase formation in a WC-Cu-based coating applied to a mild steel substrate. Emphasis is placed on understanding the solidification behaviour and its influence on defects, microstructural refinement, and carbide formation. The study provides insights into the interactions between coating constituents and the underlying substrate under controlled thermal conditions. These findings demonstrate the potential for producing functionally graded coatings tailored for demanding wear and heat dissipation applications. The approach offers a pathway for enhancing the durability and performance of steel components in extreme service environments.

In this study, we present a validated Geant4 Monte Carlo simulation model of the Dingo thermal neutron imaging beamline at the Australian Centre for Neutron Scattering. The model, constructed using CAD drawings of the entire beam transport path and shielding structures, is designed to precisely predict the in-beam neutron field at the position at the sample irradiation stage. The model’s performance was assessed by comparing simulation results to various experimental measurements, including planar thermal neutron distribution obtained in-beam using gold foil activation and 10 B 4 C-coated microdosimeters and the out-of-beam neutron spectra measured with Bonner spheres. The simulation results demonstrated that the predicted neutron fluence at the field’s centre is within 8.1% and 2.1% of the gold foil and 10 B 4 C-coated microdosimeter measurements, respectively. The logarithms of the ratios of average simulated to experimental fluences in the thermal (E th < 0.414 eV), epithermal (0.414 eV < E epi < 11.7 keV) and fast (E fast > 11.7 keV) spectral regions were approximately − 0.03 to + 0.1, − 0.2 to + 0.15, and − 0.4 to + 0.2, respectively. Furthermore, the predicted thermal, epithermal and fast neutron components in-beam at the sample stage position constituted approximately 18%, 64% and 18% of the total neutron fluence.

In this work, we extend our previously published Monte Carlo simulation model of the Dingo thermal neutron beamline at the Australian Centre for Neutron Scattering model by (1) including a sapphire crystal filter in the model, and (2) utilising the NCrystal package to simulate thermal neutron interactions with the crystalline structure. In addition to previous experimental measurements performed in the beamline’s high-resolution mode, the beam was experimentally characterised in its high-intensity mode upstream from the sample stage (at the tertiary shutter wall exit) and these measurements were used as inputs for the model. The planar neutron distributions were optimised at both the sample stage and tertiary shutter wall exit, and model predictions were validated against experimental gold wire activation measurements. For both configurations—with and without the sapphire filter—we measured neutron fluxes, and performed neutron activation analysis using 11 materials to improve the accuracy of the neutron spectrum in the model relative to the original version. Using the optimised spectrum, we simulated out-of-beam neutron spectra that were further used as the initial input in unfolding code to explore the capability of the current solution to accurately reproduce the experimental results. The normalised neutron planar distribution from the simulation was on average within 2% at the centre, and 6% and 24% at the penumbra of the experimental results at the tertiary shutter wall exit and sample stage, respectively. The specific activities predicted by the refined model were within an average of 13% and 5% of the experimentally measured activities with and without the sapphire filter, respectively. We observed a decrease of around 45% in thermal neutron flux when the sapphire filter is used, which has been reproduced by the model. The maximum value of the logarithm of the ratio of simulated to experimental out-of-beam neutron spectra across 8 locations was 0.6 compared to 2.0 in the previous work, resulting in an average normalised root mean squared error between the unfolded spectrum and experimental measurements of 5% and 9% with and without the filter, respectively. Without the sapphire filter, the optimised predicted in-beam neutron spectrum consists of around 59% thermal, 21% epithermal and 20% fast neutrons, while the addition of the filter provides an almost pure (approximately 98%) thermal neutron beam.

In recent years, W-Cu composite systems have become very interesting subjects due to good electrical and thermal conductivity, high-temperature strength, certain plasticity, and excellent radiation resistance. W-Cu composites are a very important class of materials in applications like PFM (plasma facing materials), functional graded materials (FGM), electronic packaging materials, high-voltage electrical contacts, sweating materials, shaped charge liners, electromagnetic gun-rail materials, kinetic energy penetrators, and radiation shielding/protection. There is no possibility of forming a crystalline structure between these two materials. However, due to the unique properties these materials possess, they can be used by preparing them as a composite. Generally, W-Cu composites are prepared via the conventional powder metallurgy routes, i.e., sintering, hot pressing, hot isostatic pressing, isostatic cold pressing, sintering and infiltration, and microwave sintering. However, these processes have certain limitations, like the inability to produce bulk material, they are expensive, and their adoptability is limited. Here, in this review, we will discuss in detail the fabrication routes of additive manufacturing, and its current progress, challenges, trends, and associated properties obtained. We will also explain the challenges for the additive manufacturing of the composite. We will also compare W-Cu composites to other materials that can challenge them in terms of specific applications or service conditions. The solidification mechanism will be explained for W-Cu composites in additive manufacturing. Finally, we will conclude the progress of additive manufacturing of W-Cu composites to date and suggest future recommendations based on the current challenges in additive manufacturing.

The Hapsidopareiidae is a group of “microsaurs” characterized by a substantial reduction of several elements in the cheek region that results in a prominent, enlarged temporal emargination. The clade comprises two markedly similar taxa from the early Permian of Oklahoma, Hapsidopareion lepton and Llistrofus pricei , which have been suggested to be synonymous by past workers. Llistrofus was previously known solely from the holotype found near Richards Spur, which consists of a dorsoventrally compressed skull in which the internal structures are difficult to characterize. Here, we present data from two new specimens of Llistrofus . This includes data collected through the use of neutron tomography, which revealed important new details of the palate and the neurocranium. Important questions within “Microsauria” related to the evolutionary transformations that likely occurred as part of the acquisition of the highly modified recumbirostran morphology for a fossorial ecology justify detailed reexamination of less well-studied taxa, such as Llistrofus . Although this study eliminates all but one of the previous features that differentiated Llistrofus and Hapsidopareion , the new data and redescription identify new features that justify the maintained separation of the two hapsidopareiids. Llistrofus possesses some of the adaptations for a fossorial lifestyle that have been identified in recumbirostrans but with a lesser degree of modification (e.g., reduced neurocranial ossification and mandibular modification). Incorporating the new data for Llistrofus into an existing phylogenetic matrix maintains the Hapsidopareiidae’s ( Llistrofus + Hapsidopareion ) position as the sister group to Recumbirostra. Given its phylogenetic position, we contextualize Llistrofus within the broader “microsaur” framework. Specifically, we propose that Llistrofus may have been fossorial but was probably incapable of active burrowing in the fashion of recumbirostrans, which had more consolidated and reinforced skulls. Llistrofus may represent an earlier stage in the step-wise acquisition of the derived recumbirostran morphology and paleoecology, furthering our understanding of the evolutionary history of “microsaurs.”

Advanced ceramic materials with complex design have become inseparable from the current engineering applications. Due to the limitation of traditional ceramic processing, ceramic additive manufacturing (AM) which allows high degree of fabrication freedom has gained significant research interest. Among these AM techniques, low-cost robocasting technique is often considered to fabricate complex ceramic components. In this work, aqueous ceramic suspension comprising of commercial nano-sized yttria-stabilized zirconia (YSZ) powder has been developed for robocasting purpose. Both fully and partially stabilized YSZ green bodies with complex morphologies were successfully printed in ambient conditions using relatively low-solid-content ceramic suspensions (<38 vol%). The sintered structures were able to retain the original morphologies with >94% of the theoretical density despite its high linear shrinkage (up to 33%). The microstructure analysis indicated that dense fully and partially stabilized YSZ with grain size as small as 1.40 ± 0.53 and 0.38 ± 0.10 μm can be obtained, respectively. The sintered partially stabilized YSZ solid and porous mesh samples (porosity of macro-pores >45%) exhibited hardness up to 13.29 GPa and flexural strengths up to 242.8 ± 11.4 and 57.3 ± 5.2 MPa, respectively. The aqueous-based ceramic suspension was also demonstrated to be suitable for the fabrication of large YSZ parts with good repeatability.

Hydride precipitation and distribution in hot-rolled and annealed Zircaloy-4 plate samples artificially induced by gaseous hydrogen charging were studied primarily by neutron tomography, scanning electron microscopy (SEM), and SEM-based electron backscattered diffraction techniques. The precipitated hydride platelet ( δ -ZrH 1.66 ) at a hydrogen pressure of 20 atm was found following the {111} δ -ZrH1.66 //(0001) α -Zr with the surrounding α -Zr matrix. The microstructural characterization indicated that hydrides with a relatively uniform distribution were precipitated on the rolling-transverse section of the plate, whereas, on the normal-transverse section, a hydride concentration gradient was present with a dense hydride layer near the surface. Further, the neutron tomography investigations clearly identified the nonuniform spatial distribution of hydrides. Thin hydride layers preferentially formed on the sample surface, and the concentrated hydrides precipitating at the edges/corner of the sample were observed. The causes for the localized hydride accumulation were also discussed.

In this communication, we demonstrate the use of neutron tomography for the structural characterization of iron meteorites. These materials prevalently consist of metallic iron with variable nickel content. Their study and classification is traditionally based on chemical and structural analysis. The latter requires cutting, polishing and chemical etching of large slabs of the sample in order to determine the average width of the largest kamacite lamellae. Although this approach is useful to infer the genetical history of these meteorites, it is not applicable to small or precious samples. On the base of different attenuation coefficient of cold neutrons for nickel and iron, neutron tomography allows the reconstruction of the Ni-rich (taenite) and Ni-poor (kamacite) metallic phases. Therefore, the measure of the average width of the largest kamacite lamellae could be determined in a non-destructive way. Furthermore, the size, shape, and spatial correlation between kamacite and taenite crystals were obtained more efficiently and accurately than via metallographic investigation.