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Materials Data on GdAs by Materials Project

GdAs is Halite, Rock Salt structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Gd3+ is bonded to six equivalent As3- atoms to form a mixture of edge and corner-sharing GdAs6 octahedra. The corner-sharing octahedral tilt angles are 0°. All Gd–As bond lengths are 2.95 Å. As3- is bonded to six equivalent Gd3+ atoms to form a mixture of edge and corner-sharing AsGd6 octahedra. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗

Growth, structural, and magnetic properties of single-crystal full-Heusler Co 2 TiGe thin films

This paper presents the growth, structural characterization, and measurement of magnetic properties of Co 2 TiGe thin films grown by molecular beam epitaxy on insulating MgO (001) substrates and conductive lattice matched InAlAs/InGaAs/InAlAs epitaxial layers grown on n-InP (001) substrates. A GdAs diffusion barrier was used to minimize interfacial reactions during Co 2 TiGe growth on InAlAs. The surface morphology, structural quality, and magnetic behavior were examined by reflection high-energy electron diffraction, scanning tunneling microscopy, X-ray diffraction, and superconducting quantum interference device magnetometry. The results reveal high quality Co 2 TiGe thin films with a saturation magnetization of ~1.8 μ B /formula unit and a Curie temperature of ~375 K. Finally, the magnetic easy axis was found to lie in the [110] direction but magnetometry also reveals that there is only a small difference in energy between the [110] and [010] magnetization directions.

36 MATERIALS SCIENCE↗

Back Trajectories during SAIL

This data set contains air mass back trajectories generated during the Surface Atmosphere Integrated Field Laboratory (SAIL) campaign using the Hybrid Single-Particle Lagrangian Integrated Trajectory model (HYSPLIT, Stein et al. 2015, Rolph et al. 2017). For each hour from January 1, 2021 to June 30, 2023, a 96-hour back trajectory was initiated at the SAIL sampling site, starting 100 m above ground level. The calculations used the GDAS meteorological data set with model vertical velocity. The files within this dataset show location and meteorological parameters of the back trajectory analysis. There are 21 columns within each data file. The first 2 columns pertain to back trajectory parameters: the trajectory number (which is always 1) and the meteorological grid number. The next 9 columns pertain to spatiotemporal information: the year, month, day, hour (0-23), and minute of the trajectory, the previous time of the trajectory (in negative hours), and the airmass location (latitude, longitude, and height in m AGL). The rest of the parameters within each file pertains to surface and meteorological characteristics of the airmass: pressure (in hPa), potential temperature (in K), temperature (in K), precipitation rate (in mm/hr), mixing depth (in m), relative humidity (in % relative to liquid water), specific humidity (in g/kg), H2O mixing ratio (in g/kg), underlying terrain height (in meters above sea level), and incoming radiation (in W/m^2).

back trajectory↗

Challenges in the UK Generic Design Assessment Process - 17062

In the UK, Generic Design Assessment (GDA) is a voluntary step-wise joint assessment process undertaken by the Office for Nuclear Regulation (ONR) and the Environment Agency (EA) of a generic reactor design. The process focuses purely on the reactor design and does not consider any site specific issues. The key objective of GDA is for the regulators to consider the adequacy of claims, arguments and evidence (CAE) put forward by a requesting party (RP) to demonstrate the safety of its design in the UK context. This includes all CAE relating to management of spent fuel and radioactive waste. The CAE are generally applied to a reference design put forward by the RP that is substantially complete in terms of the overall concepts and functions of the major systems, having already been deployed elsewhere. GDA assessment encompasses a broad range of topic areas which include fuel and core design, management of spent fuel, radioactive waste management and decommissioning. Other technical disciplines also have valid interests in particular aspects of the management of spent fuel. This paper summarises the UK GDA process and the types of issues raised; in particular aspects of the proposed operation of liquid waste management systems and Spent Fuel Interim Storage are presented and the instructive resolution of the RP's original limited design scope to allow the regulators to carry out a meaningful assessment. Some examples are presented and useful lessons learned for future GDAs are discussed. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗