A deuterium-deuterium (D-D) neutron generator facility has been developed with a wide range of applications in mind. D-D neutron generators provide a safe, convenient, and low-cost solution for the production of thermal, epithermal, and fast neutrons for laboratory and industrial applications. The regulatory burden for operating one of these generators is small as it contains no radioactive material and produces no radiation when turned off. One such D-D neutron generator has been installed at the National Center of Nuclear Sciences and Technologies (CNSTN). This generator produces 2.45 MeV fast neutrons with a maximum yield of 10.n/s. To maintain a strong radiation safety program, detailed knowledge of the radiation dose rates around the neutron generator is crucial for ensuring the radiological protection of the personnel involved with its operation. This work describes the Monte Carlo calculations and experimental measurements carried out in the Neutron Generator facility of the CNSTN. The adequacy of the radiation shielding of the facility was verified by measuring the neutron and gamma dose rates at various locations inside and outside the neutron generator hall during operation and comparing them with Monte Carlo calculations. Measured and calculated dose rates were in agreement to better than 20% depending on location. The operation of this neutron facility will provide a suitable neutron source for future basic and applied research.
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http://dx.doi.org/10.1016/j.apradiso.2019.01.030 | DOI Listing |
Acc Chem Res
January 2025
The Wolfson Catalysis Centre, Department of Chemistry, University of Oxford, Oxford OX1 3QR, U.K.
ConspectusThe discovery of reversible hydrogenation using metal-free phosphoborate species in 2006 marked the official advent of frustrated Lewis pair (FLP) chemistry. This breakthrough revolutionized homogeneous catalysis approaches and paved the way for innovative catalytic strategies. The unique reactivity of FLPs is attributed to the Lewis base (LB) and Lewis acid (LA) sites either in spatial separation or in equilibrium, which actively react with molecules.
View Article and Find Full Text PDFACS Phys Chem Au
January 2025
Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States.
Neutron-Transformer Reflectometry Advanced Computation Engine (), a neural network model using a transformer architecture, is introduced for neutron reflectometry data analysis. It offers fast, accurate initial parameter estimations and efficient refinements, improving efficiency and precision for real-time data analysis of lithium-mediated nitrogen reduction for electrochemical ammonia synthesis, with relevance to other chemical transformations and batteries. Despite limitations in generalizing across systems, it shows promises for the use of transformers as the basis for models that could accelerate traditional approaches to modeling reflectometry data.
View Article and Find Full Text PDFRev Cardiovasc Med
January 2025
Department of Endocrinology, The Second Affiliated Hospital of Guangzhou Medical University, 510260 Guangzhou, Guangdong, China.
Background: To study the risk of cardiovascular disease (CVD) and other competing causes of death in older kidney cancer patients.
Methods: Data on older patients (aged 65 and above) diagnosed with kidney cancer between 1975 and 2018 were extracted from the Surveillance, Epidemiology, and End Results (SEER) database. We delved into the distribution of CVD and other competing causes of death across the entire cohort and in various patient subgroups.
Polymers (Basel)
January 2025
Department of Chemistry and Pharmacy, Interdisciplinary Center for Molecular Materials, Friedrich-Alexander Universität Erlangen-Nürnberg, Egerlandstr. 3, 91058 Erlangen, Germany.
pH-responsive polyamidoamine (PAMAM) dendrimers are used as well-defined building blocks to design light-switchable nano-assemblies in solution. The complex interplay between the photoresponsive di-anionic azo dye Acid Yellow 38 (AY38) and the cationic PAMAM dendrimers of different generations is presented in this study. Electrostatic self-assembly involving secondary dipole-dipole interactions provides well-defined assemblies within a broad size range (10 nm-1 μm) with various shapes.
View Article and Find Full Text PDFInt J Mol Sci
January 2025
Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology (IIT) Delhi, New Delhi 110016, India.
Understanding the permeation of drugs through the intercellular lipid matrix of the stratum corneum layer of skin is crucial for effective transdermal delivery. Molecular dynamics simulations can provide molecular insights into the permeation process. In this study, we developed a new atomistic model representing the multilamellar arrangement of lipids in the stratum corneum intercellular space for permeation studies.
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