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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 199 records · Page 11

Tailoring conductive networks within hollow carbon nanospheres to host phosphorus for advanced sodium ion batteries

The formidable sustainability challenges in advancing energy storage technologies call for game-changing research in battery designs. The previous pursuing of novel cathode materials with high redox potentials impedes the vast applications due to the simultaneous electrolyte decomposition at high potentials, though they are expected to deliver high specific capacities. Eventually, people start thinking in an opposite way, desirable anode materials with low redox potentials can also own high specific capacities. Among all the promising candidates, phosphorus-based anodes in sodium ion batteries (SIBs) have received considerable attention owing to the low cost and relatively high natural abundance of phosphorus. More importantly, phosphorus can store three sodium atoms and enable a high theoretical capacity of 2596 mAh g -1 , which overwhelms any other SIB anode currently available. However, the poor electronic conductivity and large volume change of phosphorus during cycling severely deteriorate battery performance. The most widely used strategy is to confine phosphorus within well-designed carbon hosts. Here, we thereby introduce a new type of porous hollow carbon with conductive-network interior as phosphorus host, which not only improves the electrical conductivity, but also creates enough interior surface for maximizing phosphorus utilization and shortening the ion's diffusion distance, compared to those conventional hollow carbon hosts. Therefore, the as-prepared red phosphorus-carbon spheres composites (RP/CS) exhibit superior rate performance (similar to 1083 mAh g -1 at 4 A g -1 , similar to 837 mAh g -1 even at 8 A g -1 ) and excellent cycle life (1027 mAh g -1 at 4 A g -1 more than 2000 cycles).

25 ENERGY STORAGE↗

The impact of market design and clean energy incentives on strategic generation investments and resource adequacy in low-carbon electricity markets

Well-designed electricity markets play a crucial role in maintaining reliable electric power systems, which are critical in modern society. Here, this study examines the impact of different electricity market designs and clean energy incentive schemes on supporting renewable energy integration and achieving clean energy goals. To this end, we utilize a game-theoretical generation expansion planning model where generation companies make investment and retirement decisions to maximize their expected profit. The model is structured as an equilibrium problem with equilibrium constraints (EPEC) and solved using a diagonalization approach combined with progressive hedging. We analyze three types of electricity market designs: an energy-only market, a capacity market, and a clean energy market, and consider a wide range of market parameters resulting in 14 total scenarios. Wind and solar capacity comprise the majority of new investments in all considered scenarios, but the resultant system planning reserve margin (PRM) can differ significantly depending on market parameters. We also find that profit-driven investments lead to lower PRMs than a traditional system cost minimization approach. These individual scenario results further demonstrate how different market designs and clean energy incentive schemes may influence investor decision-making and impact resource adequacy throughout the clean energy transition.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗

Impacts and emerging research opportunities in Vehicle-Grid Integration for transportation: A review

This review provides a comprehensive examination of Vehicle-Grid Integration (VGI) technologies and their impacts on transportation systems, with a particular emphasis on the transportation-energy nexus. It systematically explores how VGI affects key transportation applications such as charging infrastructure planning, electric vehicle (EV) routing, smart charging coordination, shared mobility, and dynamic pricing. By synthesizing recent literature from both transportation and energy systems perspectives, this study highlights how advanced methodologies, such as reinforcement learning, game theory, and optimization techniques, are used to model the complex interactions between EVs, mobility patterns, and distributed energy systems. Furthermore, the review also identifies critical challenges, including behavioral factors, data limitations, and system scalability. Drawing on these insights, the paper outlines emerging research opportunities to support the design of integrated, resilient, and user-centric VGI solutions that advance sustainable mobility and energy system efficiency.

Charging coordination↗

Site-Selective Atomic Layer Deposition on Rutile TiO 2 : Selective Hydration as a Route to Target Point Defects

Routes to area-and especially site-selective atomic layer deposition (ALD) remain an enticing challenge in precision surface science, despite the potentially game-changing capability for many energy applications. An unparalleled level of surface reaction control is required to direct ALD to select sites on the same nominal material, for example, targeted growth on distinct phases, facets, step-edges, and/or defects. However, as a sequential surface synthesis method, ALD is uniquely suited to these challenges, including the possibility of selective deposition at defective surface atom arrangements. Here, we computationally identify conditions for site-selective ALD through hydration of surface defects, including oxygen vacancies and titanium interstitials on low-index rutile TiO 2 facets. First-principles computation is used to predict, as a function of temperature, the hydroxylation of defects that are targeted by proton-exchange-mediated ALD processes. In situ ellipsometric measurements of ALD Al 2 O 3 nucleation on TiO 2 (110) single crystals prepared with and without abundant oxygen vacancies demonstrate striking contrast, corroborating computational predictions and revealing a mechanistically clear path to site-selective ALD.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Nutrient supply controls the linkage between species abundance and ecological interactions in marine bacterial communities

Nutrient scarcity is pervasive for natural microbial communities, affecting species reproduction and co-existence. However, it remains unclear whether there are general rules of how microbial species abundances are shaped by biotic and abiotic factors. Here we show that the ribosomal RNA gene operon (rrn) copy number, a genomic trait related to bacterial growth rate and nutrient demand, decreases from the abundant to the rare biosphere in the nutrient-rich coastal sediment but exhibits the opposite pattern in the nutrient-scarce pelagic zone of the global ocean. Both patterns are underlain by positive correlations between community-level rrn copy number and nutrients. Furthermore, inter-species co-exclusion inferred by negative network associations is observed more in coastal sediment than in ocean water samples. Nutrient manipulation experiments yield effects of nutrient availability on rrn copy numbers and network associations that are consistent with our field observations. Based on these results, we propose a “hunger games” hypothesis to define microbial species abundance rules using the rrn copy number, ecological interaction, and nutrient availability.

59 BASIC BIOLOGICAL SCIENCES↗

Towards large-scale quantum optimization solvers with few qubits

Quantum computers hold the promise of more efficient combinatorial optimization solvers, which could be game-changing for a broad range of applications. However, a bottleneck for materializing such advantages is that, in order to challenge classical algorithms in practice, mainstream approaches require a number of qubits prohibitively large for near-term hardware. Here we introduce a variational solver for MaxCut problems over $m={{\mathcal{O}}}({n}^{k})$ binary variables using only n qubits, with tunable k > 1. The number of parameters and circuit depth display mild linear and sublinear scalings in m , respectively. Moreover, we analytically prove that the specific qubit-efficient encoding brings in a super-polynomial mitigation of barren plateaus as a built-in feature. Altogether, this leads to high quantum-solver performances. For instance, for m = 7000, numerical simulations produce solutions competitive in quality with state-of-the-art classical solvers. In turn, for m = 2000, experiments with n = 17 trapped-ion qubits feature MaxCut approximation ratios estimated to be beyond the hardness threshold 0.941. Our findings offer an interesting heuristics for quantum-inspired solvers as well as a promising route towards solving commercially-relevant problems on near-term quantum devices.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗

Frontal polymerization of thermosets to enable vacuum-formed structural electronics

Material design and accessible manufacturing are often at odds with each other, calling for creative solutions to adapt high-performance materials to available processes. This challenge is represented well by in-mold electronics, an innovative approach to the manufacture of 3D circuitry and electronic components that offers game-changing advantages. In-mold electronics relies on vacuum forming processes, which are historically limited to thermoplastics. Extending these methods to include thermosets would enable manufacturing of robust components with desirable properties. Here, we provide a solution to make thermoset materials amenable to vacuum forming. Specifically, an ambient polymerization is used to transition a liquid monomeric solution to an elastomeric gel. These free-standing gels can then be vacuum formed, and the reaction can be completed via frontal polymerization. Thermoset materials produced with this method have properties that provide benefits over traditionally employed thermoplastic substrates and enable 3D device integration into environmentally demanding architectural, automotive, and extraterrestrial structures.

Fowler, Hayden Elise [Sandia National Laboratories↗

Towards developing robust solid lubricant operable in multifarious environments

Abstract Conventional solid lubricants such as MoS 2 , graphite, or diamond-like carbon films demonstrate excellent tribological performance but only in specific environments due to their inherent materials properties. This limitation prohibits using these solid lubricants in environments that change dynamically. This study presents the results of a novel solid lubricant that was developed using a combination of solution-processed 2D-molybdenum disulfide and graphene-oxide (GO) that can be deposited on to stainless steel substrates using a simple spray-coating technique and show exceptional performance in multifarious environments namely, ambient (humid) atmosphere, dry nitrogen, and vacuum. The tribological performance of the coatings was evaluated using a ball-on-disc sliding test and demonstrated an excellent wear/friction performance in all environments and coating survived even after 44 km of linear sliding. Transmission electron microscopy and Raman spectroscopy analysis of the tribolayers suggested in-operando friction-induced re-orientation of MoS 2 layers that were protected by GO layers and, an absence of MoO x peaks indicate a strong resistance to intercalation with moisture and oxygen. The simplicity and robustness of the hybrid MoS 2 –GO solid lubricant in mitigating wear-friction behavior of steel-on-steel tribopair in a multifarious environment is a game-changing and is promising for various applications.

36 MATERIALS SCIENCE↗

Assessing health and environmental impacts of solvents for producing perovskite solar cells

Halide perovskites are poised as a game-changing semiconductor system with diverse applications in optoelectronics. Industrial entities aim to commercialize perovskite technologies because of high performance but also because this type of semiconductor can be processed from solution, a feature enabling low cost and fast production. In this work, we analyse the health and environmental impacts of eight solvents commonly used in perovskite processing. We consider first- and higher-order ramifications of each solvent on an industrial scale such as solvent production, use/removal, emissions and potential end-of-life treatments. Further, we consider the energy of evaporation for each solvent, air emission, condensation and subsequent incineration, reuse or distillation for solvent recycling, and apply a full end-of-life analysis. For human health impact, we use the ‘USEtox’ method but also consider toxicity data beyond carcinogenic classifications. We find that dimethyl sulfoxide has the lowest total impact, by being the most environmentally friendly and least deleterious to human health of the solvents considered. The analysis of the effects of these solvents on human health and the environment provides guidance for sustainable development of this new technology.

14 SOLAR ENERGY↗

Luminescent MOFs (LMOFs): recent advancement towards a greener WLED technology

The replacement of traditional incandescent, halogen and fluorescent lamps by white light emitting diodes (WLEDs) is expected to reduce the global electricity consumption by one-third by 2030, according to the US Department of Energy. The current WLED technology uses rare-earth element (REE) based phosphor materials, which, not only is cost-intensive but also constitutes an environmental concern. Hence, researchers are in a quest for a new-generation of opto-electronic materials that can replace the conventional phosphors in WLEDs and thus aim towards a cleaner and more energy efficient lighting technology for the future. Luminescent metal–organic frameworks (LMOFs) have recently emerged as a new sub-class of MOFs which have demonstrated enormous potential for applications in sensing, imaging, optoelectronics and in solid-state lighting (SSL) technology. LMOFs could be game changers as lighting phosphors due to advantages such as high luminescence quantum yield, tunable excitation and emission which can be achieved by rational design and optimization of metal centers, linkers, and the guest molecules, facile fabrication into devices, and structural robustness. These clear advantageous features of LMOFs make them score over other contemporary materials, and enable them to be futuristic phosphor materials for WLED technology. Here, in this feature article, we will provide an overview of the most recent developments of LMOF-based phosphor materials for SSL with a special focus on WLED technology. The emphasis will be centered around REE-free LMOFs, as the aim is to direct the attention of the readers towards a more viable and greener lighting technology.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Engage the Public in Science and Embrace Future Change with Human-Centric Stories, Art, and Imaginings

Human-centric stories that weave in real scientific data may be able to engage the public in environmental issues that do not yet directly affect them. Science fiction and artistically rendered futuristic scenarios can unleash the imagination and act as a lens to envision technological, social, and cultural aspects of transitioning to clean energy. Cultures with strong oral traditions use stories to record history, develop a shared identity, pass on environmental lessons, and prepare for future change. Through the lenses of our non-physical science disciplines (cultural anthropology and environmental sociology), we discuss challenges to communicating science, the use of narratives to illustrate ecosystem processes, and we report on a collaborative, interdisciplinary workshop and book project that is creating narratives of hope and visions for the future through inspiring art, short stories, and essays. We explore the surprising potential of 'cli-fi,' humor, games, and the research behind emotion and imagination-driven engagement. We describe methods that help people visualize their future well-being and we explore opportunities to spread those methods.

clean energy↗

Toward 3D data visualization using virtual reality tools

Virtual Reality (VR) offers the opportunity to display data, instrumentation, and experimental setups in three dimensions and gives the user the ability to interact with the objects. This technology moves visualization beyond two-dimensional projections on a flat screen with a fixed field of view in which a keyboard or another similar controller is needed to change the view. Advances in both hardware and software for VR make it possible for the non-expert to develop visualization tools for scientific applications both for viewing and for sharing data or diagnostic hardware between users in three dimensions. Furthermore, this manuscript describes application development using two VR software tools, Unity gaming engine and A-frame, for visualizing data and high energy physics targets.

47 OTHER INSTRUMENTATION↗

Using millimeter-sized carbon–deuterium foils for high-precision deuterium–tritium neutron spectrum measurements in direct-drive inertial confinement fusion at the OMEGA laser facility

Millimeter-sized CD foils fielded close (order mm) to inertial confinement fusion (ICF) implosions have been proposed as a game-changer for improving energy resolution and allowing time-resolution in neutron spectrum measurements using the magnetic recoil technique. This paper presents results from initial experiments testing this concept for direct drive ICF at the OMEGA Laser Facility. Additionally, while the foils are shown to produce reasonable signals, inferred spectral broadening is seen to be high (~5 keV) and signal levels are low (by ~20%) compared to expectation. Before this type of foil is used for precision experiments, the foil mount must be improved, oxygen uptake in the foils must be better characterized, and impact of uncontrolled foil motion prior to detection must be investigated.

47 OTHER INSTRUMENTATION↗

Suppressing parametric instabilities in direct-drive inertial-confinement-fusion plasmas using broadband laser light

It has long been recognized that broadband laser light has the potential to control parametric instabilities in inertial-confinement-fusion (ICF) plasmas. Here, we use results from laser-plasma-interaction simulations to estimate the bandwidth requirements for mitigating the three predominant classes of instabilities in direct-drive ICF implosions: cross-beam energy transfer (CBET), two-plasmon decay (TPD), and stimulated Raman scattering (SRS). We find that for frequency-tripled, Nd:glass laser light, a bandwidth of 8.5 THz can significantly increase laser absorption by suppressing CBET, while ∼13 THz is needed to mitigate absolute TPD and SRS on an ignition-scale platform. None of the glass lasers used in contemporary ICF experiments, however, possess a bandwidth greater than 1 THz and reaching larger values requires the use of an auxiliary broadening technique such as optical parametric amplification or stimulated-rotational-Raman scattering. An arguably superior approach is the adoption of an argon-fluoride (ArF) laser as an ICF driver. Besides having a broad bandwidth of ∼10 THz, the ArF laser also possesses the shortest wavelength (193 nm) that can scale to the high energy/power required for ICF—a feature that helps to mitigate parametric instabilities even further. We show that these native properties of ArF laser light are sufficient to eliminate nearly all CBET scattering in a direct-drive target and also raise absolute TPD and SRS thresholds well above those for broadband glass lasers. The effective control of parametric instabilities with broad bandwidth is potentially a “game changer” in ICF because it would enable higher laser intensities and ablation pressures in future target designs.

Bates, J. W. (ORCID:0000000188087240)↗

A population of free-living highland wild dogs in Indonesian Papua

A 10-day rapid assessment has confirmed a small population of indigenous wild-living dogs in the highlands of Papua Province, Indonesia. The goal of the assessment was to observe, census, assess health and reproductive status, and collect biological samples or other data for this understudied canid. Trail cameras and DNA hair traps were deployed and baited with scent attractants, and game calls were used to elicit vocal responses or lure the dogs within observation range. Adults and pups of both sexes as well as a den were documented in 149 photographs. DNA testing of scat samples confirmed a canid origin with a close relationship to other oceanic canids including NGSD (New Guinea Singing Dog) and dingoes.

Zoology↗

Reinforcement learning for bluff body active flow control in experiments and simulations

Significance Reinforcement learning (RL) has been applied effectively in games and robotic manipulation. We demonstrate the effectiveness of RL in experimental fluid mechanics by applying it to reduce the drag of circular cylinders in turbulent flow, a canonical fluid–structure interaction problem. Although physics agnostic, RL managed to reduce the drag by 30 % or reach another specified optimum point very quickly. Following this discovery, we used high-fidelity simulations to probe the underlying physical mechanisms so that the discovered control techniques can be generalized to other similar flow problems. More broadly, RL-guided active control can lead to efficient exploration of additional flow-control strategies in experimental fluid mechanics, potentially paving the way for accelerating scientific discovery and different designs in flow-related engineering problems.

42 ENGINEERING↗

Sound propagation in realistic interactive 3D scenes with parameterized sources using deep neural operators

We address the challenge of acoustic simulations in three-dimensional (3D) virtual rooms with parametric source positions, which have applications in virtual/augmented reality, game audio, and spatial computing. The wave equation can fully describe wave phenomena such as diffraction and interference. However, conventional numerical discretization methods are computationally expensive when simulating hundreds of source and receiver positions, making simulations with parametric source positions impractical. To overcome this limitation, we propose using deep operator networks to approximate linear wave-equation operators. This enables the rapid prediction of sound propagation in realistic 3D acoustic scenes with parametric source positions, achieving millisecond-scale computations. By learning a compact surrogate model, we avoid the offline calculation and storage of impulse responses for all relevant source/listener pairs. Our experiments, including various complex scene geometries, show good agreement with reference solutions, with root mean squared errors ranging from 0.02 to 0.10 Pa. Notably, our method signifies a paradigm shift as—to our knowledge—no prior machine learning approach has achieved precise predictions of complete wave fields within realistic domains.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗