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This manual describes the installation and use of the XyCe TM XDM Net list Translator. XDM simplifies the translation of netlists generated by commercial circuit simulator tools into Xyce-compatible netlists. XDM currently supports translation from PSpice and HSPICE netlists into Xyce TM netlists.
A part of the NNSA/SRNS Surplus Plutonium Disposition (SPD) project is a planned expansion of an existing facility with capabilities to handle, process, package, and characterize large amounts of plutonium oxide materials for permanent disposition at WIPP. The facility design for this future processing capability will include glovebox operations, HEPA filters, and exhaust/ventilation systems. An NNSA review of the facility support systems included comments on the potential residual reactivity of previously-stabilized PuO 2 , and on the possibility of chemical interactions between stabilized PuO 2 and a new fire suppressant (Novec TM 1230), a replacement for chlorinated/brominated compounds such as HALON TM , to be employed in the event of a room/glovebox fire where PuO 2 will be processed.
Nuclear microreactors (MRs) are a class of nuclear reactor technology, characterized by reduced dimensions, modular design, and reduced power output in contrast to conventional Light Water Reactors (LWRs). MRs are proposed for supplying electricity and eventual process heat to remote locations, such as military installations and disaster-affected areas. Current research work sponsored by the US Department of Energy Microreactor Program (MRP) is devoted to the development of novel modeling and simulation tools to better support MR vendors and regulatory bodies. Notably, the NRC is projected to utilize the CRAB multiphysics software driver for executing both design and beyond-design-basis accident analyses. Furthermore, the NRC has been utilizing the MELCOR code to calculate mechanistic source terms during accidents. Since MELCOR relies on isotopic inventory and reactor temperature/power profiles under accident conditions, which theoretically can be derived from CRAB, the goal is to establish a comprehensive CRAB-MELCOR computational framework. Past work was focused on testing and demonstrating CRAB's capability to generate results that can be used to inform mechanistic source term calculations in MELCOR. In particular, a computational workflow leveraging OpenMC-generated microscopic cross sections and CRAB was first applied to perform multiphysics microscopic depletion calculation followed by an accident scenario for a stylized microreactor problem. In fiscal year 2024, the research work has been focused on applying the OpenMC-CRAB workflow, which was first tested in fiscal year 2023, to a realistic 3D heat-pipe cooled MR problem representative of the eVinci TM design. The latter computational problem was developed with inputs from WEC to conserve selected neutronic and thermal characteristics of the eVinci TM design without releasing proprietary data. The results of this simulation, encompassing isotopic inventory, power density distribution, and kinetic parameters, will inform both MELCOR and the WEC-developed FATE code for mechanistic source terms calculations. The results from the two codes will then be compared for code verification purposes. This report contains the design characteristics of the realist heat pipe cooled microreactor developed as a use-case for the verification exercise, and the current results for the multiphysics microscopic depletion performed with the OpenMC-CRAB workflow. The results include eigenvalue as a function of time, power distribution at EOL, in addition to nuclides inventory's time evolution and spatial distribution. Finally, we report improvements to the workflow efficiency achieved through a collaboration with the NEAMS programs. Through this collaborative effort, we were able to strongly decrease the computational time for the multiphysics microdepletion calculation (i.e., from 17.4 hours to 5.7 hours on 280 processors) in addition to simplifying the interface to generate isotopics spatial distribution utilizable by FATE and MELCOR. Future work, including the improvement of the current microscopic cross-sections' library and the simulation of an accident scenario at EOL, is also discussed.
The robust Regge-pole methodology wherein is fully embedded the essential electron-electron correlation effects and the vital core polarization interaction has been used to explore negative ion formation in the large lanthanide Ho, Er, Tm, Yb, Lu, and Hf atoms through the electron elastic total cross sections (TCSs) calculations. These TCSs are characterized generally by dramatically sharp resonances manifesting ground, metastable, and excited negative ion formation during the collisions, Ramsauer-Townsend minima, and shape resonances. The novelty and generality of the Regge-pole approach is in the extraction of the negative ion binding energies (BEs) of complex heavy systems from the calculated electron TCSs. The extracted anionic BEs from the ground state TCSs for Ho, Er, Tm, Yb, Lu, and Hf atoms are 3.51 eV, 3.53 eV, 3.36 eV, 3.49 eV, 4.09 eV and 1.68 eV, respectively. The TCSs are presented and the extracted from the ground; metastable and excited anionic states BEs are compared with the available measured and/or calculated electron affinities. We conclude with a remark on the existing inconsistencies in the meaning of the electron affinity among the various measurements and/or calculations in the investigated atoms and make a recommendation to resolve the ambiguity.
TmFe2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tm3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Tm–Si bond lengths are 3.05 Å. Fe+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of corner and edge-sharing FeSi4 tetrahedra. All Fe–Si bond lengths are 2.26 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tm3+, four equivalent Fe+2.50+, and one Si4- atom. The Si–Si bond length is 2.51 Å.
TmCo2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tm3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Tm–Si bond lengths are 2.99 Å. Co+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing CoSi4 tetrahedra. All Co–Si bond lengths are 2.27 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tm3+, four equivalent Co+2.50+, and one Si4- atom. The Si–Si bond length is 2.46 Å.
TmCu2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tm3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Tm–Si bond lengths are 3.01 Å. Cu+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing CuSi4 tetrahedra. All Cu–Si bond lengths are 2.38 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tm3+, four equivalent Cu+2.50+, and one Si4- atom. The Si–Si bond length is 2.33 Å.
TmCr2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tm3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Tm–Si bond lengths are 2.97 Å. Cr+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of corner and edge-sharing CrSi4 tetrahedra. All Cr–Si bond lengths are 2.40 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tm3+, four equivalent Cr+2.50+, and one Si4- atom. The Si–Si bond length is 2.43 Å.
TmRu2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tm3+ is bonded in a 8-coordinate geometry to eight equivalent Si4- atoms. All Tm–Si bond lengths are 3.20 Å. Ru+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing RuSi4 tetrahedra. All Ru–Si bond lengths are 2.38 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tm3+ and four equivalent Ru+2.50+ atoms.
TmCu3Te3 crystallizes in the orthorhombic Pmn2_1 space group. The structure is three-dimensional. Tm3+ is bonded to six Te2- atoms to form TmTe6 octahedra that share corners with four equivalent TmTe6 octahedra, corners with ten CuTe4 tetrahedra, an edgeedge with one TmTe6 octahedra, edges with four CuTe4 tetrahedra, and faces with two CuTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 46–47°. There are a spread of Tm–Te bond distances ranging from 2.99–3.09 Å. There are four inequivalent Cu1+ sites. In the first Cu1+ site, Cu1+ is bonded to four Te2- atoms to form CuTe4 tetrahedra that share corners with three equivalent TmTe6 octahedra, corners with ten CuTe4 tetrahedra, an edgeedge with one TmTe6 octahedra, an edgeedge with one CuTe4 tetrahedra, and a faceface with one TmTe6 octahedra. The corner-sharing octahedra tilt angles range from 53–62°. There are a spread of Cu–Te bond distances ranging from 2.58–2.75 Å. In the second Cu1+ site, Cu1+ is bonded to four Te2- atoms to form CuTe4 tetrahedra that share corners with four equivalent TmTe6 octahedra, corners with ten CuTe4 tetrahedra, edges with two equivalent TmTe6 octahedra, and an edgeedge with one CuTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–64°. There are a spread of Cu–Te bond distances ranging from 2.61–2.63 Å. In the third Cu1+ site, Cu1+ is bonded to four Te2- atoms to form CuTe4 tetrahedra that share corners with three equivalent TmTe6 octahedra, corners with ten CuTe4 tetrahedra, an edgeedge with one TmTe6 octahedra, an edgeedge with one CuTe4 tetrahedra, and a faceface with one TmTe6 octahedra. The corner-sharing octahedra tilt angles range from 51–68°. There are a spread of Cu–Te bond distances ranging from 2.59–2.75 Å. In the fourth Cu1+ site, Cu1+ is bonded to four Te2- atoms to form CuTe4 tetrahedra that share corners with four equivalent TmTe6 octahedra, corners with ten CuTe4 tetrahedra, edges with two equivalent TmTe6 octahedra, and an edgeedge with one CuTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 49–61°. There are a spread of Cu–Te bond distances ranging from 2.63–2.68 Å. There are four inequivalent Te2- sites. In the first Te2- site, Te2- is bonded in a distorted hexagonal planar geometry to two equivalent Tm3+ and four Cu1+ atoms. In the second Te2- site, Te2- is bonded in a distorted hexagonal planar geometry to two equivalent Tm3+ and four Cu1+ atoms. In the third Te2- site, Te2- is bonded in a 6-coordinate geometry to two equivalent Tm3+ and four Cu1+ atoms. In the fourth Te2- site, Te2- is bonded in a 6-coordinate geometry to two equivalent Tm3+ and four Cu1+ atoms.
TmMn2Si2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Tm3+ is bonded in a distorted body-centered cubic geometry to eight equivalent Si4- atoms. All Tm–Si bond lengths are 2.99 Å. Mn+2.50+ is bonded to four equivalent Si4- atoms to form a mixture of edge and corner-sharing MnSi4 tetrahedra. All Mn–Si bond lengths are 2.35 Å. Si4- is bonded in a 9-coordinate geometry to four equivalent Tm3+, four equivalent Mn+2.50+, and one Si4- atom. The Si–Si bond length is 2.44 Å.
TmCu3Te3 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Tm3+ is bonded to six equivalent Te2- atoms to form TmTe6 octahedra that share corners with twelve equivalent CuTe4 tetrahedra, edges with three equivalent TmTe6 octahedra, and edges with six equivalent CuTe4 tetrahedra. All Tm–Te bond lengths are 3.04 Å. Cu1+ is bonded to four equivalent Te2- atoms to form CuTe4 tetrahedra that share corners with four equivalent TmTe6 octahedra, corners with six equivalent CuTe4 tetrahedra, edges with two equivalent TmTe6 octahedra, and edges with three equivalent CuTe4 tetrahedra. The corner-sharing octahedra tilt angles range from 14–59°. There are a spread of Cu–Te bond distances ranging from 2.61–2.67 Å. Te2- is bonded in a 6-coordinate geometry to two equivalent Tm3+ and four equivalent Cu1+ atoms.
TmMo6S8 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Tm3+ is bonded in a body-centered cubic geometry to eight S2- atoms. There are two shorter (2.67 Å) and six longer (2.98 Å) Tm–S bond lengths. Mo+2.17+ is bonded to five S2- atoms to form a mixture of edge and corner-sharing MoS5 square pyramids. There are a spread of Mo–S bond distances ranging from 2.42–2.58 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 1-coordinate geometry to one Tm3+ and three equivalent Mo+2.17+ atoms. In the second S2- site, S2- is bonded in a 5-coordinate geometry to one Tm3+ and four equivalent Mo+2.17+ atoms.
TmFe2O4 is Aluminum carbonitride-like structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Tm3+ is bonded to six equivalent O2- atoms to form TmO6 octahedra that share corners with six equivalent FeO5 trigonal bipyramids and edges with six equivalent TmO6 octahedra. All Tm–O bond lengths are 2.26 Å. Fe+2.50+ is bonded to five O2- atoms to form FeO5 trigonal bipyramids that share corners with three equivalent TmO6 octahedra, corners with six equivalent FeO5 trigonal bipyramids, and edges with three equivalent FeO5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. There are a spread of Fe–O bond distances ranging from 1.99–2.18 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to four equivalent Fe+2.50+ atoms to form OFe4 trigonal pyramids that share corners with four equivalent OTm3Fe tetrahedra, corners with six equivalent OFe4 trigonal pyramids, and edges with three equivalent OFe4 trigonal pyramids. In the second O2- site, O2- is bonded to three equivalent Tm3+ and one Fe+2.50+ atom to form OTm3Fe tetrahedra that share corners with nine equivalent OTm3Fe tetrahedra, corners with four equivalent OFe4 trigonal pyramids, and edges with three equivalent OTm3Fe tetrahedra.
The most common aluminum alloys utilized in the aerospace industry are 7075 and 2024 due to their high strength-to-weight ratio compared to advanced high strength steels and other aluminum alloys. Despite excellent performance, these aluminum alloys have seen limited use outside of the aerospace industry due in part to high cost. If high-performance aluminum extrusions could be made more cost effectively by eliminating energy intensive process steps typical of conventional extrusion, then numerous opportunities exist for more widespread adoption. A key reason for the high cost of 7075 and 2024 extrusions (25-75% higher than 6061) is their slow extrusion speed. 7075 and 2024 are limited to 2 m/min and 3.5 m/min respectively, in contrast to 6061 which can be extruded at 20–80 m/min. In addition to slow speed, aluminum alloys require numerous thermal treatments throughout the extrusion process including homogenization and pre-heating prior to extrusion, and solution heat treating and artificial aging after extrusion. Each of these steps contribute to the total energy consumed during manufacturing of extruded components. This project investigates the use of ShAPE to improve extrusion speed and reduce, or even eliminate, the typical thermal treatments for high strength aluminum alloys, all while improving material performance. The overarching goal of this project was to demonstrate that Shear Assisted Processing and Extrusion (ShAPE) can manufacture high-performance aluminum alloy tubing with lower manufacturing energy and improved mechanical properties compared to conventional extrusion. Unlike conventional extrusion where the billet is rammed against a stationary die using a strictly linear motion, the ShAPE process superimposes a rotational shear force by spinning the die while the billet is plunged. Compared to conventional linear extrusion, the ShAPE process imparts significantly more strain into the feedstock material, which enables the formation of novel microstructures. These microstructures manifest an array of property and process improvements for extrusion of high-performance aluminum alloys. The following accomplishments were achieved for this project: Extrusion of 7075 at 12.2 meters/min compared to 2 meters/min for conventional extrusion; Elimination of 7075 billet homogenization (430 °C for 20 hours) which is required prior to conventional extrusion; Elimination of 7075 billet pre-heating (400 °C for 1 hour) in a separate furnace which is required prior to conventional extrusion; Achieved 7075-T6with yield strength = 595 MPa, ultimate tensile strength = 531MPa, and elongation = 17.4% for extrusions made from unhomogenized billets. Exceeds the ASTM and ASM standard, and typical industry values; Achieved 7075-T5 (i.e., no solution heat treatment) with yield strength = 588 MPa, ultimate tensile strength = 535 MPa, and elongation = 14.8% for extrusions made from homogenized billets; Extrusion of 2024 at 7.4 meters/min compared to 3.5 meters/min for conventional extrusion; Achieved 2024-T8510 yield strength = 522 MPa, ultimate strength = 510MPa, and elongation = 7.1% for extrusions made from wrought billets. Exceeds the ASTM and ASM standard, and typical industry values; Extrusion of Al-12.4TM high-performance aluminum powder directly into tubing, in a single step, which eliminates process steps typical of powder metallurgy extrusion.
Photon avalanche (PA) is a highly nonlinear mode of upconversion that is characterized by 100–1000-fold increase in luminescence intensity upon minute increments of pumping power. The practical realization of numerous possible nano-bio-technology applications utilizing the PA phenomenon will require information on its susceptibility to the material volume and surface. In this report these parameters are investigated via experimental and theoretical PA. The two-color, highly nonlinear PA emission at 475 and 800 nm is clearly observed in bulk single crystal, individual microcrystals, and ensembles of colloidal core and core–shell nanoparticles of LiYF 4 host doped with either 3 or 8% of thulium ions. The properties of PA emission, such as PA nonlinearity, PA gain, PA intensity, and luminescence kinetics in these materials show dependence on crystal volume and surface quenching. Theoretical simulations provide understanding of key physical processes that influence PA performance. Moreover, photon avalanche single beam super-resolution imaging is realized for the first time in 3% Tm 3+ doped LiYF 4 core–shell nanoparticles. The obtained insights and predictions form a solid background for further development and applications of new optimized PA materials.
Four different rare-earth oxyapatites of Ca 2 RE 8 (SiO 4 ) 6 O 2 (RE = Pr, Tb, Ho, Tm) were synthesized using a solution-based method followed by drying, calcination, and high-temperature sintering in air. X-ray powder diffraction and Raman spectroscopy were performed on the synthesized oxyapatites. Here, the RE oxyapatites crystallize in the hexagonal space group P6 3 /m with similar unit cell parameters, increasing linearly with larger RE cations. The unit cell volumes increase linearly whereas the densities decrease nonlinearly with larger RE cations. Raman spectra showed intense bands of the symmetric bending and stretching modes of SiO 4 at ~ 400 and 860 cm -1 regions, respectively. The bands generally shifted to higher frequencies with smaller RE cations in the structures.
The multi-physics STAR-CCM+ code has been used to simulate the temperature and flow fields in canister gas leakage experiments conducted by using a 1/4.5-scale model storage cask. The simulations were conducted at Argonne National Laboratory’s Laboratory Computing Resource Center, utilizing high-performance computing resources. Development of STAR-CCM+ simulation models for the 1/4.5-scale model cask is described herein, followed by validation of the simulation results against experimental data. Canister depressurization and thermal response during gas leakage are discussed, along with analyses of the leakage path and allowable leakage rate. The insights gained from the STAR-CCM+ simulations and leakage analyses will help guide future experiments and actual industry applications of Argonne’s Remote Area Modular Monitoring system for canister surface temperature measurement (RAMM-TM) to enable effective aging management of spent fuel during extended dry storage, as well as help reduce risks to public safety and health and protect the environment.