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At least 289 records · Page 16

Virtual Power Plants and Energy Justice

The Federal Energy Regulatory Commission's (FERC) Order 2222, issued in September 2020, removes barriers for distributed energy resources (DERs) to participate in wholesale energy markets by allowing DERs to aggregate and participate in wholesale markets as a single entity, known as a virtual power plant (VPP). VPPs can provide balancing, reliability, and resiliency grid services and can participate in capacity, energy and ancillary services markets. They can also increase customer energy access and lower electricity bills. This report focuses on VPP business models, including considerations of energy justice (EJ). Through an analysis of the VPP value chain, business models, programs, and pilots, several VPP applications are identified and grouped by their ability to have quantitatively measurable or monetized benefits. Benefits and barriers specific to underserved communities are outlined, and VPP programs with an intentional focus on underserved communities are compared to those without such a focus.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

FY24 – FY25 Efforts to Revive the ANS-54.8 Liquid Metal Fire Protection in LMR Plants Standard

The current multi-year effort seeks to utilize national laboratory support from Argonne to expedite revival of the ANS-54.8 standard titled “Liquid Metal Fire Protection in LMR Plants.” To achieve that objective, the following tasks were identified: Task 1 involves working directly with ANS to revive the ANS-54.8 Working Group. This was to be accomplished by completing necessary paperwork, submitting that paperwork to ANS for approval, enlisting potential working group members from industry, the NRC, national laboratories, and universities, and organizing and leading Working Group activities. The overall purpose of the Working Group is to develop an updated draft of ANS-54.8 for review and approval by ANS consensus committees, the ANS Standards Board, and certification from ANSI. Task 2 focuses on leveraging historical information and expertise at Argonne related to sodium fire protection systems and strategies. For more than a decade, Argonne has worked on both international and domestic projects related to sodium fire protection system development and evaluation. The goal of this task is to utilize that experience to help inform the ANS-54.8 Working Group on important considerations that may be addressed in an updated draft of ANS-54.8. Task 3 focuses on leveraging Argonne experience in the development of and use of analysis methods and tools for the simulation of sodium fire scenarios and evaluation of the effectiveness of sodium fire protection systems and strategies. For more than a decade, Argonne has recovered, modified, and utilized several historical sodium fire analysis software tools. The goal of this task is to utilize that experience to help inform the ANS-54.8 Working Group of best practices for sodium fire progression analysis that may be addressed in an updated draft of ANS-54.8.

22 GENERAL STUDIES OF NUCLEAR REACTORS↗

Distinct Composition‐Dependent Topological Hall Effect in Mn 2‐x Zn x Sb

Abstract Spintronics, an evolving interdisciplinary field at the intersection of magnetism and electronics, explores innovative applications of electron charge and spin properties for advanced electronic devices. The topological Hall effect (THE), a key component in spintronics, has gained significance due to emerging theories surrounding noncoplanar chiral spin textures. This study focuses on Mn 2‐x Zn x Sb, a material crystalizing in centrosymmetric space group with rich magnetic phases tunable by Zn contents. Through comprehensive magnetic and transport characterizations, we found that the high‐Zn ( x > 0.6) samples display THE which is enhanced with decreasing temperature, while THE in the low‐Zn ( x < 0.6) samples show an opposite trend. The coexistence of those distinct temperature dependencies for THE suggests very different magnetic interactions/structures for different compositions and underscores the strong coupling between magnetism and transport in Mn 2‐x Zn x Sb. The findings contribute to understanding topological magnetism in centrosymmetric tetragonal lattices, establishing Mn 2‐x Zn x Sb as a unique platform for exploring tunable transport effects and opening avenues for further exploration in the realm of spintronics.

Nabi, Md Rafique Un↗

The Energy Modeling Forum (EMF)-30 Study on Short-Lived Climate Forcers: Introduction and Overview

The Energy Modeling Forum (EMF)-30 inter-comparison study on short-lived climate forcers (SLCFs) focuses on black carbon (BC) and methane, two of the most important warming SLCFs. The potential impact on climate change of methane and BC-focused emission reductions in the transport and residential sectors were quantified using nine integrated assessment models and a simple climate model. These SLCF reductions reduced global temperatures by 0.18–0.26 °C in 2050 across the models for central climate parameters, with methane being the dominant contributor. The incremental impact of SLCF-focused reductions is much smaller when combined with a broader climate policy. Individual modeling groups examined the health benefits of air pollutant reductions, climate policy co-benefits, and quantified market impacts from air pollutant damages. Model structure and set-up impact on results are discussed along with areas for future work.

Smith, Steven J.↗

Assessment of Plant and Microalgal Oil-Derived Nonisocyanate Polyurethane Products for Potential Commercialization

Green pathways for nonisocyanate polyurethane (NIPU) production have attracted increasing levels of interest. The reaction between 5-membered cyclic carbonate and polyamines is one of the most promising pathways to produce NIPU polymers. Though promising, major technical hurdles such as slow polymerization rate and poor performance hinder the commercialization of NIPU. In this paper, we screened several commercially available triglyceride oil feedstocks for NIPU products, focusing on polymerization kinetics and product performance for industrial application. The impact of carbonated group density on polymerization rate and mechanical strength was determined. We have demonstrated a remarkably higher reactivity of carbonated oil derived from feedstocks with polyunsaturated fatty acid (PUFA). The NIPU derived from such feedstocks also showed improved performance for industrial application. Unlike traditional polyurethane foam production that uses isocyanate and water to generate CO2 as a blowing reagent, there is no gas formation in NIPU polymerization. We have demonstrated a practical and cost-effective approach to produce NIPU foam material using bicarbonate as a blowing reagent. Furthermore, we conducted the first-ever technoeconomic analysis (TEA), revealing that profitable commercial NIPU production can be achieved when operating at sufficient production capacities.

09 BIOMASS FUELS↗

Magnetic toroidicity

Abstract Directional non-reciprocity refers to the phenomenon where the motion in one direction differs from the motion in the opposite direction. This behavior is observed across various systems, such as one-way traffic and materials displaying electronic/optical directional dichroism, characterized by the symmetry of velocity vectors. Magnetic toroidal moments (MTMs), which typically arise from rotational spin arrangements, also possess the symmetry of velocity vectors, making them inherently directionally non-reciprocal. In this paper, we examine magnetic point groups (MPGs) that exhibit MTMs, subsequently leading to off-diagonal linear magnetoelectricity. Our focus is on the induction of MTMs through electric fields, magnetic fields, or shear stress, while enumerating the relevant MPGs. The findings of our study will serve as valuable guidance for future investigations on directional non-reciprocity, MTMs, and off-diagonal linear magnetoelectric effects.

Physics↗

Magnetic Bloch theorem and reentrant flat bands in twisted bilayer graphene at 2 π flux

Bloch's theorem is the centerpiece of topological band theory, which itself has defined an era of quantum materials research. However, Bloch's theorem is broken by a perpendicular magnetic field, making it difficult to study topological systems in strong flux. For the first time, moiré materials have made this problem experimentally relevant, and its solution is the focus of this paper. We construct gauge-invariant irreps of the magnetic translation group at 2π flux on infinite boundary conditions, allowing us to give analytical expressions in terms of the Siegel theta function for the magnetic Bloch Hamiltonian, non-Abelian Wilson loop, and many-body form factors. We illustrate our formalism using a simple square lattice model and the Bistritzer-MacDonald Hamiltonian of twisted bilayer graphene, obtaining reentrant ground states at 2π flux under the Coulomb interaction.

2-dimensional systems↗

Mechanisms and functions of membrane lipid remodeling in plants

Lipid remodeling, defined herein as post-synthetic structural modifications of membrane lipids, play crucial roles in regulating the physicochemical properties of cellular membranes and hence their many functions. Processes affected by lipid remodeling include lipid metabolism, membrane repair, cellular homeostasis, fatty acid trafficking, cellular signaling and stress tolerance. Glycerolipids are the major structural components of cellular membranes and their composition can be adjusted by modifying their head groups, their acyl chain lengths and the number and position of double bonds. This focused review summarizes recent advances in our understanding of mechanisms of membrane lipid remodeling with emphasis on the lipases and acyltransferases involved in the modification of phosphatidylcholine and monogalactosyldiacylglycerol, the major membrane lipids of extraplastidic and photosynthetic membranes, respectively. We also discuss the role of triacylglycerol metabolism in membrane acyl chain remodeling. Finally, we discuss emerging data concerning the functional roles of glycerolipid remodeling in plant stress responses. Illustrating the molecular basis of lipid remodeling may lead to novel strategies for crop improvement and other biotechnological applications such as bioenergy production.

59 BASIC BIOLOGICAL SCIENCES↗

UNM High Energy Physics: Task B

The High Altitude Water Cherenkov (HAWC) observatory provides a unique window into the "TeV" gamma-ray universe. HAWC provides an important 1 TeV to 1000 TeV high-mass window for indirect searches for dark matter (DM) annihilation or decay. Additional fundamental physics studies benefit from HAWC's sensitivity to variable and/or transient sources. Such transient sources include: gamma ray bursts (GRBs), temporal studies of super massive black holes (specifically Markarian (Mrk) 421 and 501), and most recently searches for gamma-ray counterparts to PeV neutrino sources (observed by IceCube) and gravitational wave sources (observed by LIGO/Virgo). The UNM (Task B) research program includes leadership of the HAWC detector and of HAWC science. During this final reporting period the UNM group includes Professor John Matthews and graduate student Zhixiang Ren with the research goal focused on the development of analysis tools to enhance the sensitivity of HAWC to <1 TeV, gamma rays. This program began in 2016 with an initial focus to work to resolve known problems with the low energy analysis bins in the HAWC data. In 2017 this evolved to the development of new analysis tools to optimize current HAWC <1 TeV sensitivity as well as how HAWC (or a future HAWC-like detector) could be modified to be significantly more sensitive to <1 TeV gamma rays. In these studies Ren lead the development and evaluation of new HAWC <1 TeV analysis tools and Matthews lead the study of possible experimental modifications to HAWC to improve the <1 TeV sensitivity.

79 ASTRONOMY AND ASTROPHYSICS↗

Persistent DynAMICS

Persistent DynAMICS is a lightweight software platform that enables distributed sensing systems to operate as a unified, responsive network. It integrates with existing sensors, data systems, and processing tools as an overlay, without requiring hardware replacement or increasing user burden. As data is collected, the system identifies situations that require additional attention and directs selected sensors to gather more information. For example, if a sensor detects an unusual condition along a pipeline, the system can task nearby sensors or different sensing modalities to confirm the event and focus data collection where it is needed. To support this, the platform forms temporary groups of sensors that work together to address specific objectives. Once complete, these groups are dissolved and resources are reassigned as needed. Communication is handled through an integrated messaging framework with client and server components, enabling reliable operation and data continuity even in low-bandwidth or intermittent connectivity environments.

97 MATHEMATICS AND COMPUTING↗

Integrated TBC/EBC for SiC Fiber Reinforced SiC Matrix Composites for Next Generation Gas Turbines (Final Report)

In this ambitious project, a significant challenge preventing widespread use of ceramic matrix composites in hot section components of gas power generating turbines was addressed. Hot section components made from SiC fiber reinforced SiC matrix composites (SiC/SiC composites), have the potential to achieve a combined cycle energy efficiency of above 65%. To achieve this efficiency, the temperature of the combustion gases on the turbine component surface is expected to reach as high as ~1700ºC (3100ºF). However, SiC/SiC composites suffer from volatilization at high temperature under high velocity steam environment – typical in a turbine hot chamber. This integrated collaborative project, between two research groups at Clemson University and a team of engineers and scientists at GE Gas Power, focused on design, fabrication and evaluation of a new graded environmental barrier coating. Using the excellent compositional tailorability of polymer derived ceramics (PDCs), we developed an integrated EBC/BC that smoothly transitions from bottom SiC/SiC bond interface to hermetic sesquioxide (Y 2 O 3 ) top surface. This smooth compositional transition avoided the sharp CTE mismatch at interfaces to greatly reduce the thermal stress. The developed EBC is compatible with and bonds well with the bond coat that GE uses. The top hermetic oxide surface ensures low oxygen transportation and volatilization rates under the high velocity steam environment. The graded microstructure with increasing sesquioxide concentration also decreases the amount of Si and C elements near the top hermetic sesquioxide layer. Coatings made using a process suitable for manufacturing – atmospheric plasma spraying was demonstrated. The microstructure of coatings made using this process were fully characterized. Finally, the performance of these coatings was investigated under the most demanding conditions for this application. Specifically, high temperature, high velocity steam exposure; thermal shock test; and thermal cycling tests. The graded coatings performed exceptionally well in all these tests. Specific suggestions for future development in this area have also been identified. In addition to the excellent technical progress, this project helped initiate a robust collaboration between the research groups at Clemson and GE Gas Power. It also provided a high-quality learning and mentoring opportunity for the three post-doctoral research associates and two UG students at Clemson University who worked on this project. All proposed tasks, sub-tasks were completed, and all milestones achieved.

03 NATURAL GAS↗

Zinc against COVID-19? Symptom surveillance and deficiency risk groups

A wide variety of symptoms is associated with Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, and these symptoms can overlap with other conditions and diseases. Knowing the distribution of symptoms across diseases and individuals can support clinical actions on timelines shorter than those for drug and vaccine development. Here, we focus on zinc deficiency symptoms, symptom overlap with other conditions, as well as zinc effects on immune health and mechanistic zinc deficiency risk groups. There are well-studied beneficial effects of zinc on the immune system including a decreased susceptibility to and improved clinical outcomes for infectious pathogens including multiple viruses. Zinc is also an anti-inflammatory and anti-oxidative stress agent, relevant to some severe Coronavirus Disease 2019 (COVID-19) symptoms. Unfortunately, zinc deficiency is common worldwide and not exclusive to the developing world. Lifestyle choices and preexisting conditions alone can result in zinc deficiency, and we compile zinc risk groups based on a review of the literature. It is also important to distinguish chronic zinc deficiency from deficiency acquired upon viral infection and immune response and their different supplementation strategies. Zinc is being considered as prophylactic or adjunct therapy for COVID-19, with 12 clinical trials underway, highlighting the relevance of this trace element for global pandemics. Using the example of zinc, we show that there is a critical need for a deeper understanding of essential trace elements in human health, and the resulting deficiency symptoms and their overlap with other conditions. This knowledge will directly support human immune health for decreasing susceptibility, shortening illness duration, and preventing progression to severe cases in the current and future pandemics.

59 BASIC BIOLOGICAL SCIENCES↗

Topological orders of monopoles and hedgehogs: From electronic and magnetic spin-orbit coupling to quarks

Topological states of matter are, generally, quantum liquids of conserved topological defects. We establish this by constructing and analyzing topological field theories which introduce gauge fields to describe the dynamics of singularities in the original field configurations. In this work, homotopy groups are utilized to identify topologically protected singularities, and the conservation of their protected number is captured by a topological action term that unambiguously obtains from the given set of symmetries. Stable phases of these theories include quantum liquids with emergent massless Abelian and non-Abelian gauge fields, as well as topological orders with long-range quantum entanglement, fractional excitations, boundary modes, and unconventional responses to external perturbations. This paper focuses on the derivation of topological field theories and basic phenomenological characterization of topological orders associated with homotopy groups π n (S n ), n ≥ 1 . These homotopies govern monopole and hedgehog topological defects in d = n + 1 dimensions, and enable the generalization of both weakly interacting and fractional quantum Hall liquids of vortices to d > 2 . Hedgehogs have not been in the spotlight so far, but they are particularly important defects of magnetic moments because they can be stimulated in realistic systems with spin-orbit coupling, such as chiral magnets and d = 3 topological materials. We predict topological orders in systems with U(1) × Spin(d) symmetry in which fractional electric charge attaches to hedgehogs. Monopoles, the analogous defects of charge or generic U(1) currents, may bind to hedgehogs via Zeeman effect, or effectively emerge in purely magnetic systems. The latter can lead to spin liquids with different topological orders than that of the resonant valence bond spin liquid. Charge fractionalization of quarks in atomic nuclei is also seen as possibly arising from the charge-hedgehog attachment.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Resilience Issues in Building Energy Codes

This report, prepared for the International Energy Agency’s Building Energy Codes Working Group (BECWG, part of the IEA Energy in Buildings and Communities Technical Collaboration Programme, or IEA EBC), focuses on the application of building energy codes to improve the ability of buildings to provide a minimum healthy level of thermal comfort and function during extreme events. It reviews the relationship of building energy codes to the other building resilience policies and strategies, such as other building life/safety codes, community planning or zoning to discourage rebuilding in areas most prone to climate disasters, and other resilience planning strategies. The report provides an overview of how different jurisdictions address resilience issues in building energy codes in countries that are part of the IEA EBC Building Energy Codes Working Group.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

Equity implications of net-zero emissions: A multi-model analysis of energy expenditures across income classes under economy-wide deep decarbonization policies

With companies, states, and countries targeting net-zero emissions around midcentury, there are questions about how these targets alter household welfare and finances, including distributional effects across income groups. This paper examines the distributional dimensions of technology transitions and net-zero policies with a focus on welfare impacts across household incomes. The analysis uses a model intercomparison with a range of energy-economy models using harmonized policy scenarios reaching economy-wide, net-zero CO 2 emissions across the United States in 2050. Here we employ a novel linking approach that connects output from detailed energy system models with survey microdata on energy expenditures across income classes to provide distributional analysis of net-zero policies. Although there are differences in model structure and input assumptions, we find broad agreement in qualitative trends in policy incidence and energy burdens across income groups. Models generally agree that direct energy expenditures for many households will likely decline over time with reference and net-zero policies. However, there is variation in the extent of changes relative to current levels, energy burdens relative to reference levels, and electricity expenditures. Policy design, primarily how climate policy revenues are used, has first-order impacts on distributional outcomes. Net-zero policy costs, in both absolute and relative terms, are unevenly distributed across households, and relative increases in energy expenditures are higher for lowest-income households. However, we also find that recycled revenues from climate policies have countervailing effects when rebated on a per-capita basis, offsetting higher energy burdens and potentially even leading to net progressive outcomes. Model results also show carbon Laffer curves, where revenues from net-zero policies increase but then decline with higher stringencies, which can diminish the progressive effects of climate policies. We also illustrate how using annual income deciles for distributional analysis instead of expenditure deciles can overstate the progressivity of emissions policies by overweighting revenue impacts on the lowest-income deciles.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Demonstration of low-density, high-performance operation of sustained spheromaks and favorable scalability toward compact, low-cost fusion power plants (Final Scientific/Technical Report)

This project worked to advance the technical viability of a novel method for efficiently sustaining stable, high-performance spheromak plasma configurations to serve as the basis of compact, low-cost fusion power plants. In particular, our group worked to improve the method of Steady Inductive Helicity Injection (SIHI) with Imposed-Dynamo Current Drive (IDCD) for spheromak plasma sustainment. Prior to this project demonstrations of this plasma sustainment technology have achieved plasma performance consistent with entry milestone 3 of the BETHE FOA. Research and development (R&D) activities for this project were focused on increasing plasma performance toward a level consistent with exit milestone 4. To do this the PI and his group worked to increase the performance of sustained spheromaks produced in an existing experimental prototype (HIT-SIU) while improving confidence in projections to and design of future, higher performance devices through three primary R&D activities: 1) Improved control over the density of plasma in the device throughout a discharge to provide a pathway for demonstration of spheromaks Ohmically heating to the Mercier beta limit via: a. Fueling the device directly with plasma through the installation of pre-ionized source on the injectors b. Optimization of electrical current waveforms in the driver circuits to enable low-density plasma formation with a lower fueling rate 2) Computational demonstration of a validated, realistic injector circuit coupled to a dynamic plasma model capable of use as a design tool for SIHI drivers and associated circuits for new experimental design points on the pathway to commercial reactors. The improvements in plasma performance achieved during research activity 1), and the computational projections performed in research activity 2) increased the technological readiness level (TRL) of this fusion energy concept toward a level sufficient to attract early-stage private investment and/or other forms of follow-on investment to pursue required R&D activities required for the eventual fusion power plants based on this novel technical approach.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗

Protein kinase A in the neutron beam: Insights for catalysis from directly observing protons

Protein kinases transmit chemical signals by phosphorylating substrate proteins, thus regulating a multitude of cellular processes. cAMP-dependent protein kinase (PKA), a prototypical enzyme for the whole kinase family, has been the focus of research for several decades, however, the details of the chemical mechanism of phosphoryl group transfer have remained unknown. We used neutron crystallography to map key proton sites and hydrogen bonding interactions in the PKA catalytic subunit (PKAc) in a product complex containing adenosine diphosphate (ADP) and the phosphorylated high affinity protein kinase substrate (pPKS) peptide. To improve neutron diffraction, we deuterated PKAc allowing us to use very small crystals. In the product complex, the phosphoryl group of pPKS is protonated whereas the catalytic Asp166 is not. H/D exchange analysis of the main-chain amides and comparison with the NMR analysis of PKAc with inhibitor peptide complex revealed exchangeable amides that may distinguish the catalytic and inhibited states.

59 BASIC BIOLOGICAL SCIENCES↗

Prospects and challenges for nitrogen-atom transfer catalysis

Incorporation of nitrogen-based functional groups can profoundly impact the chemical and physical properties of organic small molecules. One-step conversion of C–H bonds to C–N bonds via C–H amination promises to streamline the synthesis of nitrogen-containing compounds. In pursuit of this promise, nitrogen-group transfer (NGT) from metal nitrenes (i.e., ligand supported M–NR complexes) has been the focus of intense research and development. In contrast, potentially complementary nitrogen-atom transfer (NAT) chemistry, in which a terminal metal nitride (i.e., ligand-supported M–N complex) engages with a C–H bond, is undeveloped. While the earliest examples of stoichiometric NAT chemistry were reported 25 years ago, catalytic protocols are only now beginning to emerge. Furthermore, we summarize the current state-of-the-art in NAT chemistry and discuss opportunities and challenges for the development of NAT catalysis as a platform for incorporation of nitrogen into organic small molecules. Specifically, we 1) highlight the synthetic complementarity of NGT and NAT chemistry, 2) discuss critical aspects of nitride electronic structure that dictate the philicity of supported metal atom, 3) examine the characteristic reactivity of metal nitrides towards substrate functionalization reactions, and 4) present emerging strategies and remaining obstacles to harnessing NAT for selective, catalytic nitrogenation of unfunctionalized organic small molecules.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗