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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Focal Area(s) The proposed white paper focuses on focal areas 2 and 3, and intends to build a pipeline to automate the detection of unresolved processes based on model errors and assist subsequent modeling solutions.
The Clear Sky Decision Support Template is a Microsoft Excel-based resource that enables users to screen and prioritize critical facilities for the addition of solar + storage. The Decision Support Template consolidates and streamlines the most relevant resources from the emergency management discipline, the electric utility sector, and national energy research institutions to assist in further site analysis and decision-making. The Decision Support Template is intended for use by local government and private sector decision-makers who aim to mitigate the effects of power outages on critical infrastructure, understand the potential for deploying photovoltaic (PV) and storage solutions on critical facilities, and align emergency management planning processes and utility needs with community resilience objectives. The Decision Support Template is divided into five modules that provide a structured, step-by-step approach users can follow and apply to unique circumstances. This process guides a more thorough and accurate assessment of a site's potential to accommodate a solar + storage system, provide grid benefits to utilities, and support community resilience and disaster mitigation for the broader region. After identifying potentially viable and preferred sites for solar + storage using the Decision Support Template, users should conduct a more detailed evaluation and consultation with a solar professional.
In April 5-7, 2022, Sandia National Laboratories hosted a second virtual workshop to further explore the potential for developing AI-enhanced co-design for microelectronics (AICoM). This second piece in an ongoing workshop series again brought together two themes. The first theme, co-design for next generation microelectronics, was drawn from the 2018 Department of Energy Office of Science (DOE SC) “Basic Research Needs for Microelectronics” (BRN) report (DOE/SC, 2018, 2021), which called for a “fundamental rethinking” of the traditional design approach to microelectronics, in which subject matter experts (SMEs) in each microelectronics discipline (materials, devices, circuits, algorithms, etc.) work near-independently. Instead, the BRN called for a non-hierarchical, egalitarian vision of co-design, wherein “each scientific discipline informs and engages the others” in “parallel but intimately networked efforts to create radically new capabilities.” The second theme, exploiting and advancing artificial intelligence (AI) to support co-design for microelectronics, acknowledges the continuing breakthroughs in AI that are currently enhancing and accelerating solutions to traditional design problems in materials synthesis and processing, circuit design, and electronic design automation (EDA).
Abstract Gravitational-wave observations of binary neutron-star (BNS) mergers have the potential to revolutionize our understanding of the nuclear equation of state (EOS) and the fundamental interactions that determine its properties. However, Bayesian parameter estimation frameworks do not typically sample over microscopic nuclear-physics parameters that determine the EOS. One of the major hurdles in doing so is the computational cost involved in solving the neutron-star structure equations, known as the Tolman–Oppenheimer–Volkoff (TOV) equations. In this paper, we explore approaches to emulating solutions for the TOV equations: multilayer perceptrons (MLPs), Gaussian processes, and a data-driven variant of the reduced basis method (RBM). We implement these emulators for three different parameterizations of the nuclear EOS, each with a different degree of complexity represented by the number of model parameters. We find that our MLP-based emulators are generally more accurate than the other two algorithms, whereas the RBM results in the largest speedup with respect to the full high-fidelity TOV solver. We employ these emulators for a simple parameter inference using a potentially loud BNS observation and show that the posteriors predicted by our emulators are in excellent agreement with those obtained from the full TOV solver.
There are many methods of incorporating more than one material in Additive Manufacturing (AM) processes. Oak Ridge National Laboratory has developed a unique solution that enables in-situ material switching by developing a dual-hopper feed system for Cincinnati’s Big Area Additive Manufacturing (BAAM) system. Continuous extrusion during a step-change in material feedstock results in a unique blended material transition region that exhibits a heterogeneous internal morphology. To improve mixing of materials during extrusion, a customized static-mixing nozzle was created for use with the BAAM. Single-bead transitions from Material A to B and B to A were printed with the mixing nozzle at a specified screw speed. Compositional analysis tracked the progression of the material transition as a function of extrudate volume. The resulting transition curves were compared against a standard nozzle configuration. Optical microscopy of cross sections also demonstrated that the static-mixing nozzle promoted a more uniform bead geometry as well as a more homogeneous internal structure throughout the material transition.
A method of sequestering gaseous carbon dioxide in which an oxide is carbonated by contacting it with a first aqueous carbonate solution to convert a portion of the oxide into a carbonate, which precipitates from solution. By converting the oxide to a solid carbonate, the CO 2 from the first carbonate solution is sequestered into the precipitate. At the same time, an aqueous hydroxide solution is formed. The aqueous hydroxide solution is contacted with gaseous carbon dioxide which sequesters the gaseous CO 2 into a second aqueous carbonate solution. The second solution so generated is then recycled back into the process and used to convert the oxide into the precipitated carbonate.
The invention relates to lithium ion batteries and, more particularly, to lithium ion conducting composite polymer electrolyte separators. The separators include a nanofiber mat composed of electrospun nanofibers. The nanofibers include a polymer having one or more polar halogen groups, a lithium-containing solid or liquid electrolyte and nanoparticle filler. The polymer, electrolyte and filler are combined to form a solution that is subjected to the electro-spinning process to produce electrospun nanofibers in the form of the mat.
Directed energy deposition (DED) is a form of additive manufacturing that uses localized melted metal, similar to traditional arc welding, to construct an object. In comparison to polymer systems, metal systems can exert additional control over the build process through manipulation of the pool of melted metal, called the “melt pool.” This is especially important to maintain appropriate layer heights and create high quality builds. Additionally, metal systems allow site-specific control of the printed part, which enables advanced construction techniques that would otherwise not be possible. However, both of these types of control require support from the slicing software and, potentially, sensor feedback. This chapter will discuss these control processes and their basic implementation in a slicing program. The processes described here lay the foundation for more advanced solutions, particularly sensor feedback, that will be discussed later.
Westinghouse Savannah River Company, the SRS Management and Operations Contractor at the time, procured six large IP-2 portable tanks capable of transporting liquids in 2003 to support the layup of the F Canyon at SRS. F Canyon was one of two full-scale hardened radiochemical separations facilities built at SRS in the 1950s as part of the initial construction of the Site. F Canyon and H Canyon provided actinide separations capabilities for SRS through the end of the Cold War. Following the end of the Cold War era, the decision was eventually made that only one of these radiochemical separations facilities at SRS would still be needed moving forward. As H Canyon was considered better suited for ongoing SRS missions, F Canyon was placed into a layup state in the first decade of the 21st Century, with F Area deactivation completing in 2006. This process resulted in the creation of excess, radioactively contaminated solutions, which required disposition. These solutions included contaminated organic solutions as well as DU-bearing aqueous solutions. The six portable tanks were procured to support the transportation of these solutions.
Compared with conventional, solution-phase approaches, solid-state reaction methods can provide unique access to novel synthetic targets. Nanothreads—one-dimensional diamondoid polymers formed through the compression of small molecules—represent a new class of materials produced via solid-state reactions, however, the formation of chemically homogeneous products with targeted functionalization represents a persistent challenge. Through careful consideration of molecular precursor stacking geometry and functionalization, we report here the scalable synthesis of chemically homogeneous, functionalized nanothreads through the solid-state polymerization of 2,5-furandicarboxylic acid. The resulting product possesses high-density, pendant carboxyl functionalization along both sides of the backbone, enabling new opportunities for the post-synthetic processing and chemical modification of nanothread materials applicable to a broad range of potential applications.
Biological lignin valorization has emerged as a major solution for sustainable and cost-effective biorefineries. However, current biorefineries yield lignin with inadequate fractionation for bioconversion, yet substantial changes of these biorefinery designs to focus on lignin could jeopardize carbohydrate efficiency and increase capital costs. We resolve the dilemma by designing ‘plug-in processes of lignin’ with the integration of leading pretreatment technologies. Substantial improvement of lignin bioconversion and synergistic enhancement of carbohydrate processing are achieved by solubilizing lignin via lowering molecular weight and increasing hydrophilic groups, addressing the dilemma of lignin- or carbohydrate-first scenarios. The plug-in processes of lignin could enable minimum polyhydroxyalkanoate selling price at as low as $6.18/kg. The results highlight the potential to achieve commercial production of polyhydroxyalkanoates as a co-product of cellulosic ethanol. Here, we show that the plug-in processes of lignin could transform biorefinery design toward sustainability by promoting carbon efficiency and optimizing the total capital cost.
A Tank-Side Cesium Removal (TSCR) system is under development by Washington River Protection Solutions to support initial production of immobilized low-activity waste (LAW) by feeding Hanford tank supernate from tank farms to the Hanford Waste Treatment and Immobilization Plant (WTP) LAW Facility. Tank waste supernate is filtered to remove suspended solids and then Cs is removed by processing it through crystalline silicotitanate (CST) ion exchange media manufactured by Honeywell UOP, LLC. The Cs-loaded CST columns will be stored indefinitely, with a goal of eventual CST removal and treatment. Thus, the spent CST needs to be recoverable after undetermined storage time. Previous testing with AP-105 simulant showed that rinsing the CST bed with 3 bed volumes (1.4 apparatus volumes [AVs]) of 0.1 M NaOH resulted in a dried bed that maintained flow characteristics indicative of ease of recovery. This study explored the intermediate conditions (between feed dried in place and the 1.4 AVs of 0.1 M NaOH rinse) to evaluate CST bed properties.
The equations of motion (EOM) for the heavy symmetrical top with one point fixed are highly nonlinear. The literature describes the numerical methods that are used to resolve this classical system, including modern tools, such as the Runge–Kutta fourth–order method. Finding the derivate of closed-form solutions for the EOM is more difficult and, as mentioned in the literature, discovering the solution is not always possible for all the EOM. Fortunately, a few examples are available that serve as a guide to move further in this topic. The purpose of this paper is to find a methodology that will produce the solutions for a given subset of EOMs that fulfill certain requisites. This paper summarizes the literature available on this topic and then follows with the derivation of the EOM using the Euler–Lagrange method. The Routhian method will be used to reduce the size of the expression, and it continues with the formulation of the classical cubic function, ƒ(u), through a novel process. The roots of ƒ(u) are of the utmost importance in finding the EOM closed-form solution, and once the final roots are selected, the general method that will produce the closed-form solutions is presented. Two sets of examples are included to show the validity of the process, and comparisons of the results from the closed-form solutions vs. the numerical results for these examples are shown.
The term “scientific workflow” has evolved over the last two decades to encompass a broad range of compositions of interdependent compute tasks and data movements. It has also become an umbrella term for processing in modern scientific applications. Today, many scientific applications can be considered as workflows made of multiple dependent steps, and hundreds of workflow systems have been developed to manage and run these scientific workflows. However, no turnkey solution has emerged from the field to address the diversity of scientific processes and the infrastructure on which they are supposed to be implemented. Instead, new research problems requiring the execution of scientific workflows with some novel feature often lead to the development of an entirely new workflow system. A direct consequence of this situation is that many existing workflow management systems (WMSs) share some salient features, offer similar functionalities, and can manage the same categories of workflows but at the same time also have some distinct capabilities that can be important for specific applications. This situation makes researchers who develop workflows face the complex question of selecting a WMS. This selection can be driven by technical considerations, to find the system that is the most appropriate for their application and for the computing and storage resources available to them, or other factors such as reputation, adoption, strong community support, or long-term sustainability. To address this problem, a group of WMS developers and practitioners joined their efforts to produce a community-based terminology of WMSs. This paper summarizes their findings and introduces this new terminology to characterize WMSs. Furthermore, this terminology is composed of fives axes: workflow structure and characteristics, composition, orchestration, data management, and metadata capture. Each axis comprises several concepts that capture the prominent features of WMSs. Based on this terminology, this paper also presents a classification of 23 existing WMSs according to the proposed axes and terms.
SRI International developed a novel, water-lean, mixed-salt-based transformational solvent technology under a U.S. Department of Energy (DOE)/National Energy Technology Laboratory (NETL)-funded project. This advanced mixed-salt process (A-MSP) can be operated with high cyclic CO 2 loading, and the solution can be regenerated with greater than 10 bar CO 2 pressure at temperatures less than 120°C. The team has created a process model and performed a techno-economic evaluation (TEA) to identify development pathways for technology advancement. The A-MSP will provide a reduction in the CO 2 capture cost and energy penalties and will have the potential for accelerated scale-up to meet the DOE’s new target of <30/tonne-CO 2 by 2030 for coal-fired power plant applications.
The direct dissolution of voloxidized used nuclear fuel (UNF) into an organic solution–comprised of diluent and specialized extractants–poses a promising alternative to the traditional liquid–liquid solvent extraction approach to reprocessing UNF. However, moving to direct dissolution removes the presence of a concentrated nitric acid aqueous phase, which has been shown to significantly influence the radiolytic longevity of extractants in conventional extraction flowsheets. Given the limited knowledge of radiation effects under direct dissolution conditions, here we present a time-resolved and dose-accumulation study on the impact of direct dissolution conditions on the radiolytic longevity of two candidate butyramide extractants, N,N-di(2-ethylhexyl) butyramide (DEHBA) and N,N-di(2-ethylhexyl)isobutyramide (DEHiBA), in pre-equilibrated n-dodecane solvent in the presence and absence of process-relevant metal ions, specifically, uranium and rhenium. Loss G(DEHBA) and G(DEHiBA) values were found to be comparable to each other, with an average of 0.37 ± 0.02 μmol J –1 , and to previous data from the γ irradiation of DEHBA and DEHiBA under conventional solvent extraction conditions. Rhenium, and by extension technetium, extraction had a modest decrease (~10%) in the overall radiolytic stability of DEHiBA only, despite >2× observed increases in chemical kinetic reactivity of the corresponding complexes with the n-dodecane radical cation. Uranium loading, on the other hand, significantly improved the lifetime of both ligands (>30%) under γ irradiation, with a greater stabilization observed for DEHBA over DEHiBA. The observed radioprotective effect afforded by uranium loading is fortuitous for the longevity of direct dissolution solvent.
Smart Grid situational awareness is provided by Energy Management Systems. A core process of these systems is State Estimation. The great majority of state estimators model the Smart Grid through a set of nonlinear algebraic equations, named the measurement model. Problem formulation considers the Gauss solution. Several model improvements have been presented regarding the Gauss solution, aiming between others to provide measurement noise robustness to the state estimation process. While considerable effort has been focused on such developments, state estimation is still constrained by the implicit modelling error, and thus inevitably vulnerable to cyber-threats. In this work, a state estimation bi-level formal model is presented towards Smart Grids enhanced situational awareness considering the concepts of synthetic measurements and innovation. Comparative test results with the state-of-the-art on the IEEE 14-bus system are presented highlighting improved situational awareness to bad data. Easy-to-implement model, without hard-to-derive parameters, built-on the classic weighted least squares solution, highlight potential aspects for real-life implementation.
Black holes in certain modified gravity theories that contain a scalar field coupled to curvature invariants are known to possess (monopole) scalar hair while non-black-hole spacetimes (like neutron stars) do not. Therefore, as a neutron star collapses to a black hole, scalar hair must grow until it settles to the stationary black hole solution with (monopole) hair. In this paper, we study this process in detail and show that the growth of scalar hair is tied to the appearance and growth of the event horizon (before an apparent horizon forms), which forces scalar modes that would otherwise (in the future) become divergent to be radiated away. We prove this result rigorously in general first for a large class of modified theories, and then we exemplify the results by studying the temporal evolution of the scalar field in scalar Gauss-Bonnet gravity in two backgrounds: (i) a collapsing Oppenheimer-Snyder background, and (ii) a collapsing neutron star background. In case (i), we find an exact scalar field solution analytically, while in case (ii) we solve for the temporal evolution of the scalar field numerically, with both cases supporting the conclusion presented above. Thus, our results suggest that the emission of a burst of scalar field radiation is a necessary condition for black hole formation in a large class of modified theories of gravity.