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Materials Data on UP2(PbO5)2 by Materials Project

UP2(PbO5)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. U6+ is bonded in a 7-coordinate geometry to seven O2- atoms. There are a spread of U–O bond distances ranging from 1.82–2.60 Å. There are two inequivalent Pb2+ sites. In the first Pb2+ site, Pb2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Pb–O bond distances ranging from 2.34–3.20 Å. In the second Pb2+ site, Pb2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Pb–O bond distances ranging from 2.39–3.21 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.55 Å) and two longer (1.56 Å) P–O bond length. In the second P5+ site, P5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.54 Å) and two longer (1.57 Å) P–O bond length. There are ten inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to three Pb2+ and one P5+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one U6+ and one P5+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one U6+ and one Pb2+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent U6+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to two Pb2+ and one P5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two Pb2+ and one P5+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Pb2+ and one P5+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one U6+ and two Pb2+ atoms. In the ninth O2- site, O2- is bonded in a distorted single-bond geometry to one U6+, two Pb2+, and one P5+ atom. In the tenth O2- site, O2- is bonded in a 1-coordinate geometry to one U6+, one Pb2+, and one P5+ atom.

36 MATERIALS SCIENCE↗

Materials Data on UP2 by Materials Project

UP2 crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. U6+ is bonded in a 9-coordinate geometry to nine P3- atoms. There are a spread of U–P bond distances ranging from 2.73–2.88 Å. There are two inequivalent P3- sites. In the first P3- site, P3- is bonded to five equivalent U6+ atoms to form a mixture of distorted edge and corner-sharing PU5 square pyramids. In the second P3- site, P3- is bonded in a 8-coordinate geometry to four equivalent U6+ and four equivalent P3- atoms. All P–P bond lengths are 2.67 Å.

36 MATERIALS SCIENCE↗

Materials Data on UP2 by Materials Project

UP2 crystallizes in the tetragonal I4mm space group. The structure is three-dimensional. there are three inequivalent U6+ sites. In the first U6+ site, U6+ is bonded in a 9-coordinate geometry to nine P3- atoms. There are a spread of U–P bond distances ranging from 2.76–2.95 Å. In the second U6+ site, U6+ is bonded in a 9-coordinate geometry to nine P3- atoms. There are a spread of U–P bond distances ranging from 2.72–2.86 Å. In the third U6+ site, U6+ is bonded in a 9-coordinate geometry to nine P3- atoms. There are a spread of U–P bond distances ranging from 2.73–2.90 Å. There are four inequivalent P3- sites. In the first P3- site, P3- is bonded to five U6+ atoms to form a mixture of edge and corner-sharing PU5 trigonal bipyramids. In the second P3- site, P3- is bonded to five U6+ atoms to form a mixture of distorted edge and corner-sharing PU5 trigonal bipyramids. In the third P3- site, P3- is bonded to five U6+ atoms to form a mixture of edge and corner-sharing PU5 square pyramids. In the fourth P3- site, P3- is bonded in a 6-coordinate geometry to four U6+ and two equivalent P3- atoms. Both P–P bond lengths are 2.43 Å.

36 MATERIALS SCIENCE↗

Groundwater table elevation and temperature from 2015 to 2024 at the Lower Montane site in the East River Watershed, Colorado.

This groundwater level elevation and temperature data package is aimed at improving the predictive understanding of hydro-biogeochemical processes at the lower montane site in the East River Watershed, Colorado. The dataset is obtained using pressure transducers placed in shallow wells in the floodplain. This dataset contains data from wells with Location ID's ER-DOW (alias DO1West), ER-DOE (alias DO2East), ER-MBA1 (alias M1Bend1), ER-MBA2 (alias M1Bend2), ER-UPW (alias UP1West), ER-UPM (alias UP2), ER-UPE (alias UP3East). Another dataset contains the data from wells with Location ID's ER-CPA1 to ER-CPA6. Each file contains the water level elevation and the water temperature. Water level elevation has been obtained using the barometric pressure from the pressure transducer (Hobos sensor) in the well, barometric pressure from a sensor in air located at the same site (lower montane), depth from top-of-casing (TOC) to sensor measurement point, and TOC elevation. Data have been checked with a few measurements of water table depths. A real-time kinematic (RTK) global positioning system (GPS) has been used to survey the TOC (data in file Well_Location.csv). The water level elevation is given in UTM13N Geoid2012AB. While depth to water level is not present in the data files, it can be easily calculated with the TOC and distance to ground provided in the GPS coordinate file. The dataset quality is discussed in Collection/Analysis section of the methods. Time-series of measurements were initially added to the archive for the period 2015 to 2019, and later updated with time-series until 2024 (end of data collection). The dataset contains 8 *.csv data files, and 3 *.csv metadata files. Feel free to contact the author with any questions or collaboration interests. The publication year was updated from "2020" to "2025" to reflect the revised version of this dataset.

54 ENVIRONMENTAL SCIENCES↗

Comparison of Industrialized Late 20th Century Flowsheets for Reprocessing Used Nuclear Fuel

This study identified and compared three flowsheets for reprocessing used nuclear fuel (UNF) industrialized in plants in the United Kingdom (the Thermal Oxide Reprocessing Plant), France (UP2-800/UP3) and Japan (the Rokkasho Reprocessing Plant). The study also identified the major implications for a plant in the United States if it were initiated. All flowsheets employed the established Plutonium Uranium Reduction Extraction (PUREX) solvent extraction technology to separate uranium and plutonium from UNF dissolved in nitric acid. However, differences in the approaches to managing iodine-129, tritium and technetium were identified in the flowsheets. A US plant would also need to separate krypton-85 as well as iodine-129 and tritium for immobilization and disposal.

11 NUCLEAR FUEL CYCLE AND FUEL MATERIALS↗

Spectral and Temporal Properties of Galactic Black Hole Systems

Kusunose, Mineshige & Yamada (1996; hereafter KMY) extended the model of Kusunose & Mineshige (1995) to the Galactic black hole candidates by considering nonthermal electron injection with gamma(EQ\0(,\s\up2(less than),\s\do-l(_))) 10. The effects of pair escape and advection on the disk structure and general relativistic effects on the emission spectrum were also examined. They found that the energy spectral index (alpha)(sub x) of the power law X-rays is about-0.8 and-2.0 when 1(sub soft)/1 = 0.2 and 2, respectively, where 1(sub soft)/1 is the ratio of the compactness of the injected soft photons to that of the gravitational energy. The power law index was found to be nearly independent of the mass accretion which is consistent with the observed luminosity independence. The model with small 1(sub soft)/1 (less than 1) shows promise for explaining the low state observed in Galactic black hole candidates. Model fits were provided for GX339-4 and Cyg X- 1 data from COMPTEL and OSSE on the Compton Gamma Ray Observatory. The difference in emission spectra between thermal disks and the model of KMY appears only in the energy range greater than 100 keV. Li, Kusunose and Liang (1996) studied stochastic particle acceleration to produce nonthermal particle distributions which then were used in the model of Kusunose & Mineshige (1995) to model the spectrum above 1 Mev from GBHC's. Under certain conditions, stochastic electron acceleration overcame Coulomb and Compton losses resulting in a suprathermal electron population. Good fits were obtained by COMPTEL and OSSE observations of Cyg X-1 and GRO J0422+23. Kusunose & Mineshige (1996a) examined the role of electron-positron pairs in advection-dominated disks. They found that the results for advection-dominated disks without pairs are not qualitatively changed by including pairs. Summaries of work sponsored by this grant are given in Wheeler, Kim, Moscoso, Kusunose & Mineshige (1996) and Kusunose (1996) Work was also done on developing a model for an e(+-) pair wind from the inner disk region of a black hole. The model consists of three zones: a pair production/annihilation zone at the base of the wind, a pair annihilation zone slightly further out from the disk and a wind zone extending to infinity where no annihilation occurs. The model assumes an input X-ray / gamma-ray power-law spectrum as a function of photon energy and angular distribution. Pairs are created in the pair production/annihilation zone via photon-photon, photonparticle and particle-particle collisions. The bulk velocity of the pairs is obtained from the momentum component perpendicular to the disk taking into account the radiation pressure acceleration of the pairs. Energy balance in the pair production/annihilation zone is calculated by assuming that the momentum component parallel to the disk is thermalized and by taking into account heating/cooling via anisotropic thermal Compton scattering along with the cooling processes of bremsstrahlung and synchrotron radiation. The pair density is also calculated. The outer boundary of the pair production/annihilation zone is where the optical depth for photon-photon pair produciton is unity. Beyond this point only pair annihilation will occur in the pair annihilation zone. When the pair density becomes small, pair annihilation will be negligible and the pairs will flow freely to infinity. In this model we have found that the X-ray power-law spectral index, alpha(sub x) is the primary parameter which determines the density, temperature and velocity of the pair production/annihilation zone (Moscoso, Kusunose & Wheeler 1996).

Wheeler, J. Craig↗