A new application of the Sohrabi albedo neutron dosimeters is reported for the first time for determination of very low-level neutron ambient dose equivalents on and around a 3.5 kJ plasma focus device (PFD). The Sohrabi dosimeters basically use a polycarbonate track detector as bare and/or in contact with B convertor(s) under special cadmium cover arrangements. Its sensitivity was improved by using enriched B under new cadmium arrangements in order to detect epithermal neutrons in addition to fast and thermal neutrons. Results of 12 dosimeters installed externally around the PFD at different azimuthal (φ) and polar (θ) angles showed that azimuthal (φ) fast, epithermal, thermal, and total neutron ambient dose equivalents were symmetric and isotropic, respectively, with values 55.15 ± 8.36, 1.36 ± 02, 0.53 ± 03, and 57.04 ± 8.62 μSv/shot at ~25 cm from anode top. Polar (θ) neutron ambient dose equivalent values on z-axis relative to 90 angle were relatively higher. Results of 38 dosimeters placed on PFD facility walls for workplace monitoring and on a BOMAB phantom at operator's location for personal dose equivalent determination showed values below minimum detection limits after exposure to 130 PFD shots. However, an operator's personal dose equivalents at ~1.0 and ~3.0 m from the anode top were estimated to be, respectively, ~13.7 and ~1.52 mSv y using azimuthal angle (φ) values if the PFD operates, for example, up to 20 shots per day for 200 d y. Even under such an extreme assumption, annual personal dose equivalent is still much below 20 mSv, the annual ICRP dose limit for workers.
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J Colloid Interface Sci
December 2024
Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300044, Taiwan; High Entropy Materials Center, Hsinchu 300044, Taiwan. Electronic address:
LiAlTi (PO) (LATP) is a promising NASICON-type solid electrolyte for all-solid-state lithium-ion batteries (ASSLIBs) owing to its high ionic conductivity, low cost, and stability in ambient atmosphere. However, the electrochemical stability of LATP suffers upon contact with lithium metals, resulting in a reduction of Ti to Ti in its structure. This limitation necessitates interface modification processes, hindering its use in lithium-ion batteries.
View Article and Find Full Text PDFSci Adv
January 2025
Department of Nuclear Engineering, University of Tennessee, Knoxville, TN 37996, USA.
Metastable phases can exist within local minima in the potential energy landscape when they are kinetically "trapped" by various processing routes, such as thermal treatment, grain size reduction, chemical doping, interfacial stress, or irradiation. Despite the importance of metastable materials for many technological applications, little is known about the underlying structural mechanisms of the stabilization process and atomic-scale nature of the resulting defective metastable phase. Investigating ion-irradiated and nanocrystalline zirconia with neutron total scattering experiments, we show that metastable tetragonal ZrO consists of an underlying structure of ferroelastic, orthorhombic nanoscale domains stabilized by a network of domain walls.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
December 2024
State Key Laboratory of Luminescent Materials and Devices &, South China Advanced Institute for Soft Matter Science and Technology, Guangdong Basic Research Center of Excellence for Energy &, Information Polymer Materials, South China University of Technology, 510640, Guangzhou, P. R. China.
Nanoimprint lithography (NIL) has been broadly applied in the fabrication of nano-patterned polymer films for cost-efficiency and high through-put; however, the intrinsic tradeoff between mechanical strength and residual stress of polymer films significantly limits the NIL resolution while the harsh processing conditions limit its versatile applications to different substrates. Herein, 1 nm metal oxide cluster, phosphotungstic acid (PTA), is used to complex with polyvinyl alcohol (PVA) for high-resolution NIL that can be operated at large-scale and mild conditions. The ultra-small size of PTA enables dense supramolecular interaction with PVA for the diminished crystallinity and accelerated chain dynamics that help relax the residual stress during film casting.
View Article and Find Full Text PDFJ Phys Chem Lett
December 2024
AstrobiologyOU, School of Environment, Earth and Ecosystem Sciences, Open University, Walton Hall, Milton Keynes MK7 6AA, United Kingdom.
Angew Chem Int Ed Engl
December 2024
College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, Beijing, 100871, China.
Purification and storage of acetylene (CH) are important to many industrial processes. The exploitation of metal-organic framework (MOF) materials to address the balance between selectivity for CH vs carbon dioxide (CO) against maximising uptake of CH has attracted much interest. Herein, we report that the synergy between unsaturated Cu(II) sites and functional groups, fluoro (-F), methyl (-CH), nitro (-NO) in a series of isostructural MOF materials MFM-190(R) that show exceptional adsorption and selectivity of CH.
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