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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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At least 307 records · Page 17

Development of a Holistic Waste Management Flow Sheet for Nuclear New Build in China - 16634

Nuclear new build is continuing to experience rapid expansion globally with China leading the pace of installed and planned new generating capacity. While new generation LWR's can be largely considered to be standardized the host countries may have legislative and regulatory drivers that can impact their environmental performance and design of waste treatment systems. Of particular issue is an increasing divergence in the technical approach to liquid waste processing in order to accommodate local environmental impacts and supply chain issues. As a global provider of LWP technology to nuclear new build EnergySolutions is seeking to standardize world class environmental performance in liquid and solid waste processing using a standardized suite of technology modules tailored for host country's needs. This approach is consistent with standardization efforts seen historically in the USA and supported by past EPRI programs. Details are provided of EnergySolutuions participation in the provision of world class liquid and solid technology to global nuclear new build. Including details of how innovative technology can be tailored to meet host country needs within the broader concept of standardization for liquid waste processing and management of resultant solid secondary waste. (authors)

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗

Long-Life Lithium-Sulfur Batteries with a Bifunctional Cathode Substrate Configured with Boron Carbide Nanowires

Developing high-energy-density lithium–sulfur (Li–S) batteries relies on the design of electrode substrates that can host a high sulfur loading and still attain high electrochemical utilization. Herein, a new bifunctional cathode substrate configured with boron-carbide nanowires in situ grown on carbon nanofibers (B 4 C@CNF) is established through a facile catalyst-assisted process. The B 4 C nanowires acting as chemical-anchoring centers provide strong polysulfide adsorptivity, as validated by experimental data and first-principle calculations. Meanwhile, the catalytic effect of B 4 C also accelerates the redox kinetics of polysulfide conversion, contributing to enhanced rate capability. As a result, a remarkable capacity retention of 80% after 500 cycles as well as stable cyclability at 4C rate is accomplished with the cells employing B 4 C@CNF as a cathode substrate for sulfur. Moreover, the B 4 C@CNF substrate enables the cathode to achieve both high sulfur content (70 wt%) and sulfur loading (10.3 mg cm -2 ), delivering a superb areal capacity of 9 mAh cm -2 . In addition, Li–S pouch cells fabricated with the B 4 C@CNF substrate are able to host a high sulfur mass of 200 mg per cathode and deliver a high discharge capacity of 125 mAh after 50 cycles.

25 ENERGY STORAGE↗

Azospirillum brasilense Bacteria Promotes Mn2+ Uptake in Maize with Benefits to Leaf Photosynthesis

Azospirillum brasilense is a prolific grass-root colonizing bacteria well-known for its ability to promote plant growth in several cereal crops. Here we show that one of the mechanisms of action in boosting plant performance is through increased assimilation of the micronutrient manganese by the host. Using radioactive 52Mn2+ (t½ 5.59 d), we examined the uptake kinetics of this micronutrient in young maize plants, comparing the performance of three functional mutants of A. brasilense, including HM053, a high auxin-producing and high N2-fixing strain; ipdC, a strain with a reduced auxin biosynthesis capacity; and FP10, a strain deficient in N2-fixation that still produces auxin. HM053 had the greatest effect on host 52Mn2+ uptake, with a significant increase seen in shoot radioactivity relative to non-inoculated controls. LA-ICP-MS analysis of root sections revealed higher manganese distributions in the endodermis of HM053-inoculated plants and overall higher manganese concentrations in leaves. Finally, increased leaf manganese concentration stimulated photosynthesis as determined by measuring leaf fixation of radioactive 11CO2 with commensurate increases in chlorophyll concentration.

59 BASIC BIOLOGICAL SCIENCES↗

The DNA glycosylase NEIL2 is protective during SARS-CoV-2 infection

SARS-CoV-2 infection-induced aggravation of host innate immune response not only causes tissue damage and multiorgan failure in COVID-19 patients but also induces host genome damage and activates DNA damage response pathways. To test whether the compromised DNA repair capacity of individuals modulates the severity of COVID-19 infection, we analyze DNA repair gene expression in publicly available patient datasets and observe a lower level of the DNA glycosylase NEIL2 in the lungs of severely infected COVID-19 patients. This observation of lower NEIL2 levels is further validated in infected patients, hamsters and ACE2 receptor-expressing human A549 (A549-ACE2) cells. Furthermore, delivery of recombinant NEIL2 in A549-ACE2 cells shows decreased expression of proinflammatory genes and viral E-gene, as well as lowers the yield of viral progeny compared to mock-treated cells. Mechanistically, NEIL2 cooperatively binds to the 5’-UTR of SARS-CoV-2 genomic RNA to block viral protein synthesis. Collectively, these data strongly suggest that the maintenance of basal NEIL2 levels is critical for the protective response of hosts to viral infection and disease.

60 APPLIED LIFE SCIENCES↗

Boosting Cell Performance of LiNi 0.8 Co 0.15 A 0.05 O 2 via Surface Structure Design

Although the high energy density and environmental benignancy of LiNi 0.8 Co 0.15 A 0.05 O 2 (NCA) holds promise for use as cathode material in Li-ion batteries, present low rate capabilities, and fast capacity fade limit its broad commercial applications. Here, it is reported that surface modification of NCA cathode (R-3m) with 5 nm-thick nanopillar layers and Fm-3m structures significantly improves electrode structure, morphology, and electrochemical performance. The formation of nanopillar layers increases cycling and working voltage stability of NCA by shielding the host material from hydrofluoric acid and improves structural stability with the electrolyte. The modified NCA cathode exhibits an enhanced 89% capacity retention at a rate of 1 C over that of pristine NCA (75.2%) after 150 cycles and effectively suppresses working voltage fade (a drop of 0.025 V after 300 cycles) during repeated charge-discharge cycles. In addition, the diffusion barrier of Li ions in NCA crystals at 0.80 V is noticeably smaller than that of Li ions in pristine NCA (0.87 eV). These findings demonstrate that this unique surface structure design considerably enhances cycle and rate performance of NCA, which has potential applications in other Ni-rich layered cathode materials.

25 ENERGY STORAGE↗

Interface Promoted Reversible Mg Insertion in Nanostructured Tin-Antimony Alloys

This paper demonstrates intermetallic compounds SnSb are highly active materials for reversibly hosting Mg ions. Compared with monometallic Sn and Sb, SnSb alloy exhibited exceptionally high reversible capacity (420 mAh/g), excellent rate capability and good cyclic stability. Mg insertion into pristine SnSb involves an activation process to complete, which induces particle breakdown and results in phase segregation to Sn-rich and Sb-rich phases. Both experimental analysis and DFT simulation suggest that the Sn-rich phase is particularly active and provides most of the capacity whereas the Sb-rich phase is not as active, and the interface between these two phases play a key role in promoting the formation and stabilization of the cubic Sn phase that is more favorable for fast and reversible Mg insertion. We further show that activated SnSb alloy has good compatibility with simple Mg electrolytes. Overall, this work could provide new approaches for designing materials capable of reversible Mg ion insertion and new opportunities for understanding Mg electrochemistry.

Environmental Molecular Sciences Laboratory↗

Interface Aspects in All‐Solid‐State Li‐Based Batteries Reviewed

Abstract Extensive efforts have been made to improve the Li‐ionic conductivity of solid electrolytes (SE) for developing promising all‐solid‐state Li‐based batteries (ASSB). Recent studies suggest that minimizing the existing interface problems is even more important than maximizing the conductivity of SE. Interfaces are essential in ASSB, and their properties significantly influence the battery performance. Interface problems, arising from both physical and (electro)chemical material properties, can significantly inhibit the transport of electrons and Li‐ions in ASSB. Consequently, interface problems may result in interlayer formation, high impedances, immobilization of moveable Li‐ions, loss of active host sites available to accommodate Li‐ions, and Li‐dendrite formation, all causing significant storage capacity losses and ultimately battery failures. The characteristic differences of interfaces between liquid‐ and solid‐type Li‐based batteries are presented here. Interface types, interlayer origin, physical and chemical structures, properties, time evolution, complex interrelations between various factors, and promising interfacial tailoring approaches are reviewed. Furthermore, recent advances in the interface‐sensitive or depth‐resolved analytical tools that can provide mechanistic insights into the interlayer formation and strategies to tailor the interlayer formation, composition, and properties are discussed.

25 ENERGY STORAGE↗

A nickel-foam@carbon-shell with a pie-like architecture as an efficient polysulfide trap for high-energy Li–S batteries

A high-loading sulfur cathode is critical for establishing rechargeable lithium–sulfur (Li–S) batteries with the anticipated high energy density. However, its fabrication as well as realizing high electrochemical utilization and stability with high-loading sulfur cathodes is a daunting challenge. Here, we present a new pie-like electrode that consists of an electrocatalytic nickel-foam as a “filling” to adsorb and store polysulfide catholytes and an outer carbon shell as a “crust” for facilitating high-loading sulfur cathodes with superior electrochemical and structural stabilities. The inner electrocatalytic nickel-foam is configured to adsorb polysulfides and facilitate their redox reactions. The intertwined carbon shell assists to shield the polysulfides within the cathode region of the cell. Both the nickel-foam and the carbon shell have high conductivity and porous space, which serve simultaneously as interconnected current collectors to enhance the redox kinetics and as polysulfide reservoirs to confine the active material. The effectiveness of such a pie-like structure in improving the electrochemical efficiency enables the cathode to host an ultrahigh sulfur loading of 40 mg cm -2 and attain a high areal capacity of over 40 mA h cm -2 at a low electrolyte/sulfur (E/S) ratio of 7. The enhanced cyclability is reflected in a high reversible areal capacity approaching 30 mA h cm -2 at C/5 rate after 100 cycles and excellent rate capability up to 2C rate.

25 ENERGY STORAGE↗

Investigating Benefits and Challenges of Converting Retiring Coal Plants into Nuclear Plants

A coal-to-nuclear (C2N) transition means siting a nuclear reactor at the site of a recently retired coal power plant. Three overarching questions from the C2N transition guide this research: where in the United States are retired coal facilities located and what factors make a site feasible for transition; what factors of technology, cost, and project timeline drive investor economics over such a decision; and how will C2N impact local communities? The study team evaluated the siting characteristics of recently retired plants and those operating coal-fired power plant sites run by a utility or an independent power producer utilizing publicly available data to screen U.S. coal power plant sites to nuclear-feasible locations. After screening all retired coal sites to a set of 157 potential candidates and screening operating sites to a set of 237 candidates, the study team estimates that 80% of retired and operating coal power plant sites that were evaluated have the basic characteristics needed to be considered amenable to host an advanced nuclear reactor. For the recently retired plant sites evaluated, this represents a capacity potential of 64.8 GWe to be backfit at 125 sites. For the operating plant sites evaluated, this represents a capacity potential of 198.5 GWe to be backfit at 190 sites. This report evaluates a case study for the detailed impacts and potential outcomes from a C2N transition. Based on the nuclear technology choices and sizes evaluated to replace a large coal plant of 1,200 MWe generation capacity at the case study site, nuclear overnight costs of capital could decrease by 15% to 35% when compared to a greenfield construction project, through the reuse of infrastructure from the coal facility. Nuclear replacement designs can have a lower capacity size because nuclear power plants run at higher capacity factors than coal power plants. In the case study replacing coal capacity with 924 GWe of nuclear capacity, the study team found regional economic activity could increase by as much as $\$275 million$ and add 650 new, permanent jobs to the region of analysis. The evaluated site choice in the report is hypothetical for analysis purposes only and based on available data and documented assumptions. Consequently, the findings only inform at a general level. A community, investor, or other interested stakeholder can use these results to set up a detailed, in-depth analysis for a specific application of interest, such as evaluating a C2N transition of a specific coal power plant and a specific nuclear technology design. The report was subjected to independent peer reviews by experts in systems engineering and regional economic modeling to evaluate analysis and assumptions.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Tubular titanium oxide/reduced graphene oxide-sulfur composite for improved performance of lithium sulfur batteries

Lithium sulfur (LiS) batteries are promising alternatives to conventional Li-ion batteries in terms of specific capacity and energy. But, the technical challenges raised from the soluble polysulfide (PS) in organic electrolyte deter their implementation in practical applications. Nanoengineered structure and chemical adsorptive materials hold great promise in mitigating the PS migration problem. We develop a tubular titanium oxide (TiO 2 )/reduced graphene oxide (rGO) composite structure (TG) as a sulfur hosting material for constructing better performed LiS batteries. The TG/sulfur cathode (TG/S) is able to deliver ~1200 mAh g -1 specific capacity with stable operation for over 550 cycles. Moreover, the TG/S composite cathode shows stable Coulombic efficiencies of over ~95% at various C rates, which are ~10% higher than those of the rGO/sulfur (G/S) counterparts. The superior electrochemical performances of TG/S could be ascribed to the synergistic effects between the conductive rGO support and the physically/chemically absorptive TiO 2 , that is, the spatial tubular structure of TiO 2 provides intimate contact and physical confinement for sulfur, while the polar TiO 2 in TG/S shows strong chemical interaction towards the sulfur species.

25 ENERGY STORAGE↗

A genome-wide RNA interference screen identifies a role for Wnt/β-catenin signaling during Rift Valley Fever Virus infection

Rift Valley fever virus (RVFV) is an arbovirus within the Bunyaviridae family capable of causing serious morbidity and mortality in humans and livestock. To identify host factors involved in bunyavirus replication, we employed genome-wide RNA interference (RNAi) screening and identified 381 genes whose knockdown reduced infection. The Wnt pathway was the most represented pathway when gene hits were functionally clustered. With further investigation, we found that RVFV infection activated Wnt signaling, was enhanced when Wnt signaling was preactivated, was reduced with knockdown of β-catenin, and was blocked using Wnt signaling inhibitors. Similar results were found using distantly related bunyaviruses La Crosse virus and California encephalitis virus, suggesting a conserved role for Wnt signaling in bunyaviral infection. We propose a model where bunyaviruses activate Wnt-responsive genes to regulate optimal cell cycle conditions needed to promote efficient viral replication. The findings in this study should aid in the design of efficacious host-directed antiviral therapeutics. IMPORTANCE RVFV is a mosquito-borne bunyavirus that is endemic to Africa but has demonstrated a capacity for emergence in new territories (e.g., the Arabian Peninsula). As a zoonotic pathogen that primarily affects livestock, RVFV can also cause lethal hemorrhagic fever and encephalitis in humans. Currently, there are no treatments or fully licensed vaccines for this virus. Using high-throughput RNAi screening, we identified canonical Wnt signaling as an important host pathway regulating RVFV infection. The beneficial role of Wnt signaling was observed for RVFV, along with other disparate bunyaviruses, indicating a conserved bunyaviral replication mechanism involving Wnt signaling. Lastly, these studies supplement our knowledge of the fundamental mechanisms of bunyavirus infection and provide new avenues for countermeasure development against pathogenic bunyaviruses.

59 BASIC BIOLOGICAL SCIENCES↗

Continuous plating/stripping behavior of solid-state lithium metal anode in a 3D ion-conductive framework

Significance Solid-state lithium metal anode possesses great promise owing to its high energy density and improved safety. This work introduces a strategy for constructing a 3D Li metal anode, which is hosted in a solid-state ion-conducting host and shows a safe and dendrite-free plating/stripping behavior. The host is based on a garnet-type ion-conductive framework and a bottom-deposited Cu current collector. The Li anode is plated within the solid garnet framework from the bottom Cu layer and shows a dendrite-free deposition behavior, effectively averting the dendrite penetration issue. Owing to the 3D ion-conductive host, the volume change and interface contact problem of the Li anode have been significantly mitigated, realizing a high-capacity and safe Li metal anode for solid-state high-energy-density batteries.

25 ENERGY STORAGE↗

Functional team selection as a framework for local adaptation in plants and their belowground microbiomes

Abstract Multicellular organisms are hosts to diverse communities of smaller organisms known as microbiomes. Plants have distinctive microbiomes that can provide important functions related to nutrition, defense, and stress tolerance. Empirical studies provide convincing evidence that in some—but not all—circumstances, belowground microbiomes help plants adapt to their local environment. The purpose of this review is to develop functional team selection (FTS) as a framework to help predict the conditions necessary for root microbiomes to generate local adaptation for their plant hosts. FTS envisions plants and their microbiomes as complex adaptive systems, and plant adaptations as emergent properties of these systems. If plants have the capacity to recognize and cultivate beneficial microbes and suppress pathogens, then it is possible for plants to evolve the capacity to gain adaptations by curating their microbiome. In resource-limited and stressful environments, the emergent functions of complex microbial systems may contribute to positive feedback linked to plant vigor, and ultimately, local adaptation. The key factors in this process are: (i) selective force, (ii) host constitution, (iii) microbial diversity, and (iv) time. There is increasing interest in harnessing beneficial microbial interactions in agriculture and many microbial growth-promoting products are commercially available, but their use is controversial because a large proportion of these products fail to consistently enhance plant growth. The FTS framework may help direct the development of durable plant-microbiome systems that enhance crop production and diminish pathogens. It may also provide valuable insights for understanding and managing other kinds of host-microbe systems.

Environmental Sciences & Ecology↗

Developing a Process for Collaboration-Based Siting of a Federal Consolidated Interim Storage Facility in the United States: Learning from Communities Living with Legacy Waste

In June of 2023, the U.S. Department of Energy (DOE), Office of Nuclear Energy (NE) announced the selection of its Collaboration-Based Siting (CBS) Consortia, a group of 12 awardees, including the Consortium for Risk Evaluation with Stakeholder Participation (CRESP) (led by Vanderbilt University) to assist DOE-NE with the development of its process for siting a federal consolidated interim storage facility (FCISF) for spent nuclear fuel (SNF) storage. At this time, DOE NE is not soliciting interested host communities, rather the CBS Consortia are tasked with in-depth engagement, mutual learning, and capacity building to provide DOE NE with feedback on the CBS process. CRESP’s objective is to engage communities in two regions (the Pacific Northwest and the Southeast) with sites currently storing defense- and research-related SNF to foster learning concerning the best and worst practices in community participation in risk-informed decision making. This includes learning from existing structures for public input in radioactive waste management decision making [e.g. citizen advisory boards (CABs)] and other local parties about how to build and sustain trust among the parties. CRESP has been working to engage stakeholders and Tribes surrounding two DOE sites historically differing in receptiveness to engaging with DOE and trusting in DOE to accomplish its missions. CRESP’s approach to date has consisted of (1) engaging voluntarily members and former members of the DOE Office of Environmental Management’s CABs to develop a mutual understanding of their perspectives, values, and experiences related to risk and participatory decision making; (2) engaging members of those communities that would likely be part of any radioactive waste management discussions and who may provide valuable feedback for the development of the CBS process; and in the longer term, (3) engaging communities to foster knowledge sharing on understanding and definitions of risk and how risk is factored into community decision making. Our emphasis is to identify opportunities for improving risk communication frameworks, strategies, and decision making. The selection of a future FCISF site is likely to result in the creation of a structure similar to a CAB composed of members of the local community. We anticipate that these insights can help DOE NE learn from existing participatory risk communication structures in place at sites storing defenseor research-related SNF to understand best practices for fostering enduring and participatory relationships with future CABs. Within this paper, we (1) describe CRESP’s overall approach to assisting DOE NE with maturing the CBS process; (2) present a summary of preliminary phase 1 project results, including the development of a body of knowledge (describing available resources to support community engagement, risk communica tion, and participatory decision making) and community ecosystem information (leveraging demographic, social, economic, and environmental attribute mapping and advanced sentiment analysis of social media data); and (3) based on these results, provide observations for future research opportunities to support the development of CBS processes for radioactive waste management facilities, generally.

collaboration-based siting↗

Bacterial synergies amplify nitrogenase activity in diverse systems

Endophytes are microbes living within plant tissue, with some having the capacity to fix atmospheric nitrogen in both a free-living state and within their plant host. They are part of a diverse microbial community whose interactions sometimes result in a more productive symbiosis with the host plant. Here, we report the co-isolation of diazotrophic endophytes with synergistic partners sourced from two separate nutrient-limited sites. In the presence of these synergistic strains, the nitrogen-fixing activity of the diazotroph is amplified. One such partnership was co-isolated from extracts of plants from a nutrient-limited Hawaiian lava field and another from the roots of Populus trees on a nutrient-limited gravel bar in the Pacific Northwest. The synergistic strains were capable of increasing the nitrogenase activity of different diazotrophic species from other environments, perhaps indicating that these endophytic microbial interactions are common to environments where nutrients are particularly limited. Multiple overlapping mechanisms seem to be involved in this interaction. Though synergistic strains are likely capable of protecting nitrogenase from oxygen, another mechanism seems evident in both environments. The synergies do not depend exclusively on physical contact, indicating a secreted compound may be involved. This work offers insights into beneficial microbial interactions, providing potential avenues for optimizing inocula for use in agriculture.

60 APPLIED LIFE SCIENCES↗

WIND Toolkit Power Data Site Index

This spreadsheet contains per-site metadata for the WIND Toolkit sites and serves as an index for the raw data hosted on Globus connect (nrel#globus:/globusro/met_data). Aside from the metadata, per site average power and capacity factor are given. This data was prepared by 3TIER under contract by NREL and is public domain. Authoritative documentation on the creation of the underlying dataset is at: Final Report on the Creation of the Wind Integration National Dataset (WIND) Toolkit and API: http://www.nrel.gov/docs/fy16osti/66189.pdf

17 WIND ENERGY↗

Navigation Flight Test Results from the Low Power Transceiver Communications and Navigation Demonstration on Shuttle (CANDOS) Experiment

This paper presents the Global Positioning System (GPS) navigation results from the Communications and Navigation Demonstration on Shuttle (CANDOS) experiment flown on STS-107. This experiment was the initial flight of a Low Power Transceiver (LPT) that featured high capacity space- space and space-ground communications and GPS- based navigation capabilities. The LPT also hosted the GPS Enhanced Orbit Determination Experiment (GEODE) orbit determination software. All CANDOS test data were recovered during the mission using LPT communications links via the Tracking and Data Relay Satellite System (TDRSS). An overview of the LPT s navigation software and the GPS experiment timeline is presented, along with comparisons of test results to the NASA Johnson Space Center (JSC) real-time ground navigation vectors and Best Estimate of Trajectory (BET).

Haas, Lin↗

Binder-Stabilized Carbon Fiber Hosts for High-Utilization Sodium–Polysulfide Flow Catholytes

Sodium-sulfur (Na-S) batteries hold promise as high-energy-density batteries for long-duration energy storage due to their high open circuit voltage and Earth-abundant active materials. However, low utilization of the sulfur active material limits the achievable specific capacity, especially when a liquid polysulfide catholyte is utilized. High-surface-area carbon materials demonstrate promise to increase sulfur utilization in a Na-S battery. To make the carbon host material applicable for a flow battery application, a binder is required to bind the carbon materials together and to a porous substrate. Here, we utilize a composite carbon paper electrode coated by polymer,carbon nanofibers (CNFs) and carbon black (CB). By varying the mass ratios of CNF to CB, we found that a 70/20/10 mass ratio of CNF/CB/binder provided the highest capacity (260 mAh g −1 compared to the baseline of 156 mAh g −1 ) and stable battery performance over 100 cycles. Analysis of the composite electrode and full cells reveals that the amount of CB in the composite electrode influences binder distribution, cell resistance, and full cell performance.

Lehmann, Michelle L. [Oak Ridge National Laborator↗