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In this report, we summarize the progress made in FY23 for experiments fielded at Triangle Universities Nuclear Laboratory (TUNL) of Duke University on the neutron scattering measurements of 238 U. The preliminary results on the elastic and inelastic reaction channels will be presented in addition to details of experiment and data analysis.
Experimental 238 U PFNS were reviewed in detail including Chi-Nu PFNS. 7/10 data sets have been accepted. We have performed a detailed UQ using LANL code ARIADNE and templates of expected PFNS measurement uncertainties. we have included Chi-Nu PFNS in experimental data base. The extended Los Alamos model in CoH was used for prior calculation. Multiple chance fission and pre-equilibrium (with exciton model) contributions were modeled.
This presentation contains a high-level description of the Idaho National Laboratory Laboratory Directed Research and Development (LDRD) project, 20A44-121: Modeling and characterization of α-U to accelerate metallic fuels development. It frames the problem, describes a motivation, outlines the research plan involving multiscale modeling and experiments, discusses impact and details research developments.
While quantum computing offers the promise of exponential advantages, limited quantum speedups are known, especially for practical applications. To open new avenues for quantum advantages, we propose Unconventional Quantum Advantages for Computation (U-QuACs), with respect to unconventional resources such as space (number of bits or quantum bits of memory required to solve a problem), accuracy of solution, communication, or energy consumption. We focus on space-efficient quantum algorithms, where we seek to design algorithms that solve a problem using much less space than the total size of the input. A natural setting in which space is critical is the streaming model of computation, where the input data arrives sequentially in pieces that must each be processed individually. Streaming is motivated by a variety of problems including analysis of internet traffic or social networks. We design the first exponential quantum space advantage for a natural streaming problem, which also constitutes the first quantum advantage for approximating a discrete optimization problem, albeit with respect to space.
For light nuclei, preliminary work extends the evaluation from 6.5 MeV to ~ 10 MeV. For 139 La, the team delivered full evaluation in fast region to ORNL, including covariances. For sup>235 U, RPI data simulations, the team performed simulations and showed some improvement for neutrons below 5 MeV. Some of the changes needed for more improvement might not be supported by the current format. Some of the changes above 12 MeV to account for the angular distribution of preequilibrium neutrons require a change in the PFNS evaluation procedure.
Fission yield evaluations rely not only on precise measurements, but also on clear documentation of experimental conditions especially the energy of incident neutrons inducing fission. In the EXFOR database, following the convention adopted in past evaluations, the incident neutron energy has traditionally been divided in only three energy groups: thermal, fast and 14 MeV. The information is stored in the EN-DUMMY field, which often serves as a placeholder in the presence of broad-spectrum or reactor-based sources. This work reviews 238 U(n,f) entries in EXFOR that use EN-DUMMY, identifying cases where better energy estimates can be made based on the original publications, facility characteristics, or reconstructed neutron spectra. We assign new cross-section-weighted average energies where possible. The revised independent and cumulative fission yield data are compiled for future use in model development and evaluation efforts.
It is well known that age hardening occurs in U-6%Nb (Ref. 1-9). Figure 1 shows that increases in hardness occur at aging temperatures up to ~400°C, and overaging occurs above ~450°C. Overaging occurs by cellular decomposition of the αʺ b martensite, similar to overaging reactions in other uranium alloys. But the mechanism of age hardening remains elusive, particularly in its early stages.
Concrete is a critical component of nuclear power plants; thus, its safety and reliability must be thoroughly examined throughout the life cycle of the structural system. During the life cycle of this infrastructure, monitoring of the concrete for signs of degradation should be performed through nondestructive evaluation (NDE). Ultrasonic measurements have been an industry standard for both surface and subsurface inspections. As such, Oak Ridge National Laboratory (ORNL) is developing advanced image reconstruction algorithms to overcome the limitations of traditional ultrasonic NDE methodologies. The results and discussion presented herein summarize the current state of the ultrasonic model–based iterative reconstruction (U-MBIR) algorithm developed at ORNL.
We review data and evaluations for neutron-induced fission for the actinides 233 U, 238 Pu, 240 Pu and 242 Pu. These isotopes are part of common nuclear fuel cycles, especially for modern fast reactors. We focus on incident neutrons in the energy range of 100 keV to 20 MeV and compare the experimental data from the literature to the major evaluated libraries ENDF/B-VIII.1, JENDL-5, and JEFF-3.3, as well as to LLNL’s ENDL-2009.5 library. Based on the assessment of the fission cross sections, we provide recommendations on which library to use. Additional assessments covering other reaction channels will be provided separately.
The Metallic Fuels Irradiation and Physics Database (FIPD) is an organized collection of legacy metallic fuel U(Pu)Zr data, measurements, and reactor conditions from the Experimental Breeder Reactor II (EBR-II) and the Fast Flux Test Facility (FFTF). The database provides a wealth of information and is easily accessed and utilized by the U.S. nuclear industry and the Nuclear Regulatory Commission (NRC). The database contains three categories of data. The first category covers fuel pin fabrication specifications, including fuel slug diameter and length, cladding diameter, smeared density, etc. The second consists of operational conditions, which include axial distributions of power, temperature, fluence, burnup, isotopic density, etc. The third category contains post-irradiation examination (PIE) results, largely collected at facilities now part of the Idaho National Laboratory (INL), formerly part of Argonne National Laboratory -West (ANL-W) and at the Alpha-Gamma Hot Cell Facility (AGHCF) at Argonne National Laboratory, comprising fission gas release and chemistry analysis, profilometry measurements, neutron radiography data, etc. All these data have been organized and preserved in FIPD.
We propose a protocol for the scalable quantum simulation of SU(N)×U(1) lattice gauge theories with alkaline-earth like atoms in optical lattices in both one- and two-dimensional systems. The protocol exploits the combination of naturally occurring SU(N) pseudo-spin symmetry and strong inter-orbital interactions that is unique to such atomic species. A detailed ab initio study of the microscopic dynamics shows how gauge invariance emerges in an accessible parameter regime, and allows us to identify the main challenges in the simulation of such theories. We provide quantitative results about the requirements in terms of experimental stability in relation to observing gauge invariant dynamics, a key element for a deeper analysis on the functioning of such class of theories in both quantum simulators and computers.
U-shape flexural plates (UFPs) have gained significant attention in seismic structural design due to their ability to provide stable hysteresis behaviour and serve as effective energy-dissipating devices. Concurrently, Additive Manufacturing (AM) has advanced significantly, enabling the production of metallic components with mechanical properties comparable to those of conventionally manufactured cold-rolled materials. This study aims to explore the seismic response of single and double UFP fabricated through Laser Powder Based Fusion (LPBF) and conventional cold rolled 316L stainless steel (SS). The experimental results are evaluated based on force-displacement hysteresis behaviour, energy dissipation capacity, load-carrying capacity, and stiffness degradation. The findings confirm the efficacy of AM-fabricated UFPs for seismic energy dissipation. Additionally, the results suggest the potential for further improvement through the optimization of AM process parameters, such as laser scan speed, hatch spacing, and layer thickness, to enhance hysteretic performance and energy dissipation characteristics.
This document describes the “MicroVision-MV003” dataset. This folder contains three subfolders: “originals”, “predicted_masks”, and “gt_masks”. The “originals” folder contains 720 original images acquired using two imaging modalities: 360 images from overhead imaging and 360 images from transmission (raw) imaging. Naming scheme:YYYY-MM-dd__plate_strain_nitrogen-level_replication_experiment_imaging-modalityYYYY-MM-dd: 2024-12-20, 2024-12-21, 2024-12-22,2024-12-23,2024-12-24,2024-12-25,2024-12-26,2024-12-27,2024-12-28,2024-12-29,2024-12-30,2024-12-31.plate: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30.strain: FG, LE.nitrogen-level: N-1, N-10, N-100.replication: 1, 2, 3, 4, 5.experiment: MV.003.imaging-modality: overhead, transmission (raw). For example, the image2024-12-20__1_FG_N-10_3_MV.003_overheadwas taken on 2024-12-20. The plate number is 1, the fungal strain is FG, the nitrogen treatment is N-10, and the replication number is 3 for experiment MV.003, acquired using the overhead imaging modality. The “predicted_masks” folder contains masks generated by a trained U-Net model for the transmission imaging modality.The “gt_masks” folder contains 326 human hand-traced masks that serve as ground truth.
Spin-lattice Hamiltonian for trivalent positive Nd and U ions in sites of tetragonal symmetry in calcium fluoride measured with electron spin resonance
Direct one phonon spin-lattice relaxation times for positive trivalent Nd and U ions in calcium difluoride at tetragonal symmetry sites
Report provides computer-calculated curves and tables for the daughter buildup of Ra-226, Ac-227 and U-232 chains. Data are presented as a function of time beginning with pure samples of each parent. The information may be of interest to those using decay chains as isotopic alpha sources or neutron sources.
Poly A-poly U synthesized by Azotobacter Vinelandi RNA polymerase in unprimed reaction containing ATP and UTP, following short lag period
Neutron capture cross sections of molybdenum, tantalum, and U-238 and neutron flux spectrum measurements using He-3 proportional counter