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At least 253 records · Page 14

Data for Stetten et al. (2025), "Biogeochemical controls on iron speciation and cycling across upland to shoreline gradients in freshwater and estuarine coastal soils (Lake Erie and Chesapeake Bay, United States)"

Coastal environments are dynamic interfaces that mediate carbon and nutrient exchanges between terrestrial landscapes and open waters, but it is unclear how biogeochemical reactions, in particular iron (Fe) redox transformations, affect the understanding and prediction of coastal ecosystem functions. This dataset includes measurements from two freshwater sites in the Western and Central basins of Lake Erie (Ohio, United States) and two estuarine sites in the Chesapeake Bay (Maryland, United States); the analytical results were reported by Stetten et al. (2025) in Science of the Total Environment. It was produced as part of the COMPASS-FME project, which seeks to advance a scalable, predictive understanding of the fundamental biogeochemical processes, ecological structure, and ecosystem dynamics that distinguish coastal terrestrial-aquatic interfaces from the purely terrestrial or aquatic systems to which they are coupled. The sites were sampled in November 2022 (CRC), December 2022 (MSM), February 2023 (GCW), and March 2023 (OWC); site codes follow those used by Pennington et al. (2025).The dataset consists of the following soil data:- Solid data (Fe concentration, etc.)- Porewater data (sulfate, sulfide, etc.)- Linear combination fitting results of X-ray absorption near edge structure (XANES) spectra; i.e., quantitative results of the oxidation state of Fe, indicated as a proportion of pure Fe(III) and Fe(II) model compounds- Linear combination fitting results of EXAFS (extended X-ray absorption fine structure) spectra, indicated as proportion of of Fe-model compounds (illite, smectite, etc.)Each data type has a single file in comma-separated value (CSV) format. No special software is required to read it.

54 ENVIRONMENTAL SCIENCES↗

Magnetization of Materials in Pulsed Magnetic Fields

Magnetism has proven pivotal in the development of many technologies. From navigation compasses, imaging devices in medicine and electric motors, exploitation of the magnetic field on both the macroscopic and atomic scale has played an important role in human development. There is particular interest in the magnetic properties of materials, especially due to the incomplete understanding of why some materials behave magnetically in a specific manner. This has been motivated in some cases by the desire to engineer compounds to fulfil specific roles. One group of compounds being investigated for this purpose are known as molecular magnets, so-called as they are formed of discrete molecule-based units with metal ions providing a magnetic moment while organic or inorganic molecules bridge these metal centres. They can be large, discrete molecular clusters (referred to as 0-D molecular magnets) or long coordination networks in 1-D, 2-D or 3-D. The dimensionality here refers to the number of directions in which spins communicate: all directions (3-D), only in planes (2-D), only in chains (1-D) or no long range communication (0-D). These organometallic compounds, they are sometimes referred to as metal organic frameworks (MOFs) though there is some discrepancy in conventions in regards to whether MOFs should be different from molecular magnets. Molecular magnets offer flexible synthesis routes towards magnetic materials. Being transition complexes, ligands can be substituted to refine the magnetic properties of the final product or the metallic centre can be changed. This can be accomplished through as simple a method as different reactant ratios Materials with novel properties are also being sought such as magnetoelectric multiferroic compounds which display simultaneous ferromagnetism and ferroelectricity.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Dense Plasma Focus Modeling

The mechanisms for pinch formation in Dense Plasma Focus (DPF) devices, with the generation of high-energy ions beams and subsequent neutron production over a relatively short distance, are not fully understood. Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics and its associated instabilities and neutron production.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Next Generation Workload Management and Analysis System for Big Data

We report on the activities and accomplishments of a four-year project (a three-year grant followed by a one-year no cost extension) to develop a next generation workload management system for Big Data. The new system is based on the highly successful PanDA software developed for High Energy Physics (HEP) in 2005. PanDA is used by the ATLAS experiment at the Large Hadron Collider (LHC), and the AMS experiment at the space station. The program of work described here was carried out by two teams of developers working collaboratively at Brookhaven National Laboratory (BNL) and the University of Texas at Arlington (UTA). These teams worked closely with the original PanDA team – for the sake of clarity the work of the next generation team will be referred to as the BigPanDA project. Their work has led to the adoption of BigPanDA by the COMPASS experiment at CERN, and many other experiments and science projects worldwide.

97 MATHEMATICS AND COMPUTING↗

Dense Plasma Focus Modeling

Here we report on high-fidelity 2D and 3D numerical magnetohydrodynamic (MHD) simulations using the LA-COMPASS code to study the pinch formation dynamics in a DPF and the associated instabilities and neutron production.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

NESHAP Area-Specific Dose-Release Factors for Potential Onsite Member-of-the-Public Locations at SRS using CAP88-PC Version 4.0

The Environmental Protection Agency (EPA) requires the use of the computer model CAP88-PC to estimate the total effective doses (TED) for demonstrating compliance with 40 CFR 61, Subpart H (EPA 2006), the National Emission Standards for Hazardous Air Pollutants (NESHAP) regulations. As such, CAP88 Version 4.0 was used to calculate the receptor dose due to routine atmospheric releases at the Savannah River Site (SRS). For estimation, NESHAP dose-release factors (DRFs) have been supplied to Environmental Compliance and Area Closure Projects (EC&ACP) for many years. DRFs represent the dose to a maximum receptor exposed to 1 Ci of a specified radionuclide being released into the atmosphere. They are periodically updated to include changes in the CAP88 version, input parameter values, site meteorology, and location of the maximally exposed individual (MEI). In this report, the DRFs were calculated for potential radionuclide atmospheric releases from 13 SRS release points. The three potential onsite MEI locations to be evaluated are B-Area, Three Rivers Landfill (TRL), and Savannah River Ecology Lab Conference Center (SRELCC) with TRL’s onsite workers considered as members-of-the-public, and the potential future constructions of dormitories at SRELCC and Barracks at B-Area. Each MEI location was evaluated at a specified compass sector with different area to receptor distances and was conducted for both ground-level and elevated release points. The analysis makes use of area-specific meteorological data (Viner 2014). The resulting DRFs are compared to the 2014 NESHAP offsite MEI DRFs for three operational areas; A-Area, H-Area, and COS for a release rate of 1 Ci of tritium oxide at 0 ft. elevation. CAP88 was executed again using the 2016 NESHAP MEI release rates for 0 and 61 m stack heights to determine the radionuclide dose at TRL from the center-of-site (COS).

54 ENVIRONMENTAL SCIENCES↗

Research Library Year in Review 2016

2016 was a year of strategy, analysis and moving forward. We launched January with a strategic planning process. Building on the Lab’s Strategic Plan and Purpose Statement, we created a process that reached out to Lab leadership, scientists & engineers, and Research Library (RL) staff. An external consultant was engaged to help drive the process and to lead a fullday staff retreat. A survey was created and administered to staff, seeking feedback on priorities and direction. A parallel survey was created for stakeholders. Stakeholder questions began with the macro – from the external climate to Lab and division priorities – to the micro concerning priorities and directions for the RL. Stakeholders were personally interviewed by teams of two that included an interviewer and a scribe. These thirty-plus interviews were collated into a spreadsheet. A sociologist provided semantic analysis for the feedback, creating an impact document of the interviews. The full day retreat provided an opportunity for staff to build on their feedback as well as stakeholder feedback. A great deal of brainstorming led to categorized priorities and scenarios. The RL Compass Team, encompassing library leadership, moved the next stage of the process forward by taking retreat feedback and creating a first draft of a plan. Two more rounds of feedback with smaller staff groups as well as the Library Advisory Board led to the final plan. The core plan is included in this report.

96 KNOWLEDGE MANAGEMENT AND PRESERVATION↗

Community Project for Accelerator Science and Simulation-3

The focus of the Rensselaer efforts for COMPASS-3 was the development of parallel mesh adaptation procedures for high-order unstructured meshes where elements must be curved to properly approximate the domain geometry. The procedures developed were integrated into the ACE3P accelerator modeling code. Areas of development included: High order curved mesh representations that can provide the orders of geometric approximation needed. A curved mesh adaptation procedure that can match an adaptively defined anisotropic mesh metric field. In-memory integration of these procedures with the Omega3P code to provide an effective parallel adaptive simulation work flow. Improved dynamic load balancing tools that account for the degrees of freedom associated with the various order mesh entities (vertices, edges, faces and regions).

42 ENGINEERING↗

Scoping Analysis of MACCS Modeling Improvements for the Study of Protective Action Recommendations

In late 2004, the U.S. Nuclear Regulatory Commission (NRC) initiated a project to analyze the relative efficacy of alternative protective action strategies in reducing consequences to the public from a spectrum of nuclear power plant core melt accidents. The study is documented in NUREG/CR-6953, “Review of NUREG-0654, Supplement 3, ‘Criteria for Protective Action Recommendations for Severe Accidents,’” Volumes 1, 2, and 3. The Protective Action Recommendations (PAR) study provided a technical basis for enhancing the protective action guidance contained in Supplement 3, “Guidance for Protective Action Strategies,” to NUREG-0654/FEMA-REP-1, Rev. 1, “Criteria for Preparation and Evaluation of Radiological Emergency Response Plans and Preparedness in Support of Nuclear Power Plants, ” dated November 2011. In the time since, a number of important changes and additions have been made to the MACCS code suite, the nuclear accident consequence analysis code used to perform the study. The purpose of this analysis is to determine whether the MACCS results used in the PAR study would be different given recent changes to the MACCS code suite and input parameter guidance. Updated parameters that were analyzed include cohorts, keyhole evacuation, shielding and exposure parameters, compass sector resolution, and a range of source terms from rapidly progressing accidents. Results indicate that using updated modeling assumptions and capabilities may lead to a decrease in predicted health consequences for those within the emergency planning zone compared to the original PAR study.

21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS↗

Towards Combined QCD Global Analysis of Polarized and Unpolarized PDFs and Fragmentation Functions

We present a new global QCD analysis of spin-dependent PDFs (SPDF) and fragmentation functions (FF) performed by the JAM (Jefferson Lab Angular Momentum) Collaboration, based on all available data on inclusive spin structure functions from CERN, SLAC, DESY and JLab, and all semi-inclusive hadron production data from electron-positron annihilation experiments, including the most resent measurements from Belle and BaBar. Preliminary results on combined SPDFs and FFs using polarized semi-inclusive data from COMPASS and HERMES will be presented.

Sato, N.↗

Hadron Spectroscoy at JPAC

We review some of the recent achievements of the Joint Physics Analysis Center, a theoretical collaboration with ties to experimental collaborations, which aims at providing amplitudes suitable for the analysis of the experimental data on hadron physics. Since its foundation in 2013, the group is focused on hadron spectroscopy in preparation for the present and forthcoming high statistics experiments, as Belle II, BESIII, CLAS12, GlueX, COMPASS and LHCb.

Pilloni, Alessandro↗

Unraveling hadron transverse momentum in SIDIS: Dynamics, present data, future measurements

The transverse momentum of hadrons observed in the current fragmentation region of SIDIS is generally compounded of several parts: the intrinsic transverse momentum of partons in the target, the effects of QCD radiation, and the broadening due to the fragmentation process. Unraveling the different contributions is a major challenge that needs to be addressed before one can reliably apply QCD factorization formulas and extract information about TMD distributions. Recent pion/kaon multiplicity data from HERMES and COMPASS indicate that non-perturbative dynamics plays an essential role in the measured $P_T$ distributions, particularly at z >~ 0.5. In this talk I briefly summarize (a) what our present knowledge of non-perturbative dynamics suggests regarding the magnitude of the different contributions to hadron transverse momentum; (b) what SIDIS measurements could/should be done to unravel the different contributions; (c) what could be learned from measurements of particle correlations between the current and target fragmentation regions. The talk will be a concise summary and aim to provide input to the discussions. It relates mainly to the topics of Sessions 1 and 2 of the program.

Weiss, Christian↗

3D partonic structure of the nucleon

A a great deal of experimental and theoretical progress has been achieved in our understanding of partonic structure of hadrons in recent decades. I will discuss our current understanding of hadron structure from the point of view of Quantum Chromodynamics, the theory that describes the hadron as dynamical system of partons (quarks and gluons). I will emphasize the emerging concept of 3D (three-dimensional) parton distributions and discuss their formal definition, evolution, and phenomenology. Jefferson Lab 12 and COMPASS will play crucial role in experimental measurements of hadron structure. I will explain details of the program and show the potential of future measurements. I will also discuss future of nuclear physics beyond Jefferson Lab 12 at a proposed Electron-Ion Collider.

Prokudin, Alexei↗

Multi-shock design tools in double shell models

The essence of the project was to implement a program in python that demonstrated certain models put forth by fusion physicists. Across the time spent at Los Alamos National Laboratory, much was spent programming. Though fundamentally programmatical in nature, the task contained considerable difficulty hid within mathematically deriving and manipulating the models while maintaining data discretization. The result of solving these complications gave invaluable experience in applied mathematics. The final product, a piece of lengthy code, ended up having the full range of desired capabilities, with plans for more. Given the laser power history from a pulse shot on NIF, Omega, or any other Inertial Confinement Fusion facility, the code maps the terrain of radiation temperature inside the hohlraum throughout the period of the shot. Additionally, shock wave convergence prediction was implemented as additional capability. As the name of the project suggests, this tool acts as a compass of direction for researchers designing laser power profiles. Further development of this tool will undoubtedly assist in the research conducted on single and double-shell indirect ICF, consequently expanding the capabilities of operating stewardship over the national nuclear stockpile.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Thermal Scattering Law Data Development for Paraffin Wax

Paraffin wax is often used as a nuclear moderator to slow down the fast neutrons in experimental critical assemblies [1]. It is a colorless and soft solid material that consists primarily of straight-chain alkanes (n-alkanes), which are hydrocarbons with the general formula CnH2n+2 [2-3]. The length of the hydrocarbon chain ranges from C20 to C30 and higher [2]. It is distinguished by its solid state at room temperature and begins to melt above approximately 310 K [4]. Paraffin wax is a commonly employed substance in the manufacture of shielding. One of its noteworthy characteristics is its ability to effectively absorb the neutrons. Also, it possesses a high macroscopic cross section, which enables it to efficiently moderate neutrons. As a result, paraffin wax is extensively utilized in various applications where moderation and shielding of neutrons are needed. For simulations, it is necessary to evaluate its thermal scattering law (TSL) and cross sections. Computationally, classical molecular dynamics (CMD) simulations provide the capability of simulating atomic details. For example, several unary, binary, and few multi component mixtures have been investigated of the paraffin model by using molecular dynamics simulations [5-12]. An assessment of thermal neutron scattering in a heavy paraffinic oil treated both as a solid and a viscous fluid containing 25% linear branched paraffin (C30H62), 35% one ring cycloalkane (C30H60), 15% two rings cycloalkane (C30H58), and 25% aromatic (C30H60) chains has been studied using CMD simulations for producing TSL data [13]. Nevertheless, there is lack of TSL and cross section data for paraffin wax as most of the reported analyses focus on the unary and binary mixture of n-alkanes, which is not consistent with actual paraffin wax [2]. In this work, we applied the equilibrium CMD simulations technique to explore the structure and dynamical properties of wax, which are fundamental input to calculate the TSL. A paraffin wax system was modeled using the CMD code LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) [14-15] with the semi-empirical COMPASS [16] force field. The density of state (DOS) was calculated from the normalized velocity autocorrelation function (VACF), which is the Fourier transform of the normalized VACF. The DOS was used for the calculation of the TSL and thermal scattering cross sections. The paraffin wax atomic system was constructed by using the MedeA material design platform [17], and was benchmarked using available properties (i.e., density, bond lengths, angles, diffusivity, and viscosity).

Nuclear Criticality Safety Program (NCSP)↗

Route Energy Prediction (RouteE) Powertrain Validation Report

The National Renewable Energy Laboratory's flagship package in the RouteE suite, RouteE-Powertrain, is a mesoscopic energy model that predicts vehicle energy consumption given discrete attributes that describe each segment or link in a vehicle's path on a road network. High-frequency, physics-based, powertrain simulators, such as NREL's FASTSim, are well-suited to model vehicle energy consumption when real driving data and a detailed understanding of the vehicle powertrain specifications are available. However, there are a variety of situations in the past, present (real-time), and future where high-frequency driving data and/or vehicle information may not be available, but reliable energy consumption is still desired, such as energy-aware vehicle routing. These are the ideal applications for RouteE-Powertrain. The suite of RouteE tools also includes RouteE-Compass, which is an eco-routing software that incorporates energy consumption into network routing algorithms, and RouteE-Mobile, which is a prototype smartphone navigation app to demonstrate the integrated capabilities of the RouteE suite for real-world eco-routing. The focus of this validation report is to share key metrics about the data sets and models behind RouteE-Powertrain. The set of RouteE-Powertrain models discussed in this report are made available through the RouteE web API through the NREL Developer Network.

33 ADVANCED PROPULSION SYSTEMS↗

Data Quality Assessment of Optiwatt Vehicle Telematics Data

In October 2024, the Idaho National Laboratory (INL) received data from Optiwatt (Compass Global, Inc.) describing the driving and charging behavior of electric vehicle (EV) drivers. The data shared had been collected from approximately 10,000 vehicles and included vehicle specifications, driving information like odometer readings at the beginning and end of origin-destination pairs (i.e., trips with identification of home for trip start and end for Tesla vehicles), and charging information such as charging energy consumed per charge session and if the charge occurred at home. The vehicle data were provided from 9 EV makes and 18 EV models, with production years ranging from 2012–2024, but more than 9,500 of the vehicles were Tesla EVs. The data includes more than six million trips and more than three million charging events that occurred between June 2023 to Aug 2024 and collected from California and the Eastern United States. The purpose of this report is to review the quality of the data received from Optiwatt and the feedback INL received from Optiwatt after data concerns were shared with them.

33 - ADVANCED PROPULSION SYSTEMS↗