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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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Feasibility of Using Calcium Silicate Carbonation to Synthesize High-Performance and Low-Carbon Cements
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An integrated approach to realizing high-performance liquid-junction quantum dot sensitized solar cells
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Fluorination of a polymer donor through the trifluoromethyl group for high-performance polymer solar cells
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Toward a persistent event-streaming system for high-performance computing applications
High-performance computing (HPC) applications have traditionally relied on parallel file systems and file transfer services to manage data movement and storage. Alternative approaches have been proposed that use direct communications between application components, trading persistence and fault tolerance for speed. Event-driven architectures, as popularized in enterprise contexts, present a compelling middle ground, avoiding the performance cost and API constraints of parallel file systems while retaining persistence and offering impedance matching between application components. However, adapting streaming frameworks to HPC workloads requires addressing challenges unique to HPC systems. This paper investigates the potential for a streaming framework designed for HPC infrastructures and use cases. We introduce Mofka, a persistent event-streaming framework designed specifically for HPC environments. Mofka combines the capabilities of a traditional streaming service with optimizations tailored to the HPC context, such as support for massively multicore nodes, efficient scaling for large producer-consumer workflows, RDMA-enabled high-performance network communications, specialized network fabrics with multiple links per node, and efficient handling of large scientific data payloads. Built using the Mochi suite of HPC data service components, Mofka provides a lightweight, modular, and high-performance solution for persistent streaming in HPC systems. We present the architecture of Mofka and evaluate its performance against Kafka and Redpanda using benchmarks on diverse platforms, including Argonne's Polaris and Oak Ridge's Frontier supercomputers, showing up to 8× improvement in throughput in some scenarios. We then demonstrate its utility in several real-world applications: a tomographic reconstruction pipeline, a workflow for the discovery of metal-organic frameworks for carbon capture, and the instrumentation of Dask workflows for provenance tracking and performance analysis.
High-performance liquid chromatography of oligoguanylates at high pH
Because of the stable self-structures formed by oligomers of guanosine, standard high-performance liquid chromatography techniques for oligonucleotide fractionation are not applicable. Previously, oligoguanylate separations have been carried out at pH 12 using RPC-5 as the packing material. While RPC-5 provides excellent separations, there are several limitations, including the lack of a commercially available source. This report describes a new anion-exchange high-performance liquid chromatography method using HEMA-IEC BIO Q, which successfully separates different forms of the guanosine monomer as well as longer oligoguanylates. The reproducibility and stability at high pH suggests a versatile role for this material.
Indoor air quality in 24 California residences designed as high-performance homes
Today’s high performance green homes are reaching previously unheard of levels of airtightness and are using new materials, technologies and strategies, whose impacts on Indoor Air Quality (IAQ) cannot be fully anticipated from prior studies. This research study used pollutant measurements, home inspections, diagnostic testing and occupant surveys to assess IAQ in 24 new or deeply retrofitted homes designed to be high performance green buildings in California. Although the mechanically vented homes were six times as airtight as non-mechanically ventilated homes (medians of 1.1 and 6.1 ACH 50 , n=11 and n=8, respectively), their use of mechanical ventilation systems and possibly window operation meant their median air exchange rates were almost the same (0.30 versus 0.32 hr -1 , n=8 and n=8, respectively). Pollutant levels were also similar in vented and unvented homes. In addition, these similarities were achieved despite numerous observed faults in complex mechanical ventilation systems. More rigorous commissioning is still recommended. Cooking exhaust systems were used inconsistently and several suffered from design flaws. Failure to follow best practices led to IAQ problems in some cases. Ambient nitrogen dioxide standards were exceeded or nearly so in four homes that either used gas ranges with standing pilots, or in Passive House-style homes that used gas cooking burners without venting range hoods. Homes without active particle filtration had particle count concentrations approximately double those in homes with enhanced filtration. The majority of homes reported using low-emitting materials; consistent with this, formaldehyde levels were approximately half those in conventional, new CA homes built before 2008. Emissions of ultrafine particles (with diameters <100 nm) were dramatically lower on induction electric cooktops, compared with either gas or resistance electric models. These results indicate that high performance homes can achieve acceptable and even exceptional IAQ by providing adequate general mechanical ventilation, using low-emitting materials, providing mechanical particle filtration, incorporating well-designed exhaust ventilation for kitchens and bathrooms, and educating occupants to use the kitchen and bath ventilation.
Facile, ethylene glycol-promoted microwave-assisted solvothermal synthesis of high-performance LiCoPO 4 as a high-voltage cathode material for lithium-ion batteries
Olivine-type LiCoPO 4 is considered a promising high-voltage cathode material for next-generation lithium-ion batteries. However, preparing high-performance LiCoPO 4 by a simple approach has been challenging. Herein, we present a facile and rapid (30 min) one-step microwave-assisted solvothermal synthesis route using a 1 : 1 (v/v) water/ethylene glycol (EG) binary solvent mixture and a temperature of 250 °C. Here, the technique delivers high-performance LiCoPO4nanoparticles without additional post-annealing or carbon coating steps. The as-prepared powder consists of single crystalline LiCoPO 4 and features a hexagonal platelet-like morphology with dimensions of 700-800 nm × 400-600 nm × 100-220 nm. Selected area electron diffraction (SAED) experiments reveal that the platelets show the smallest dimension along [010], which is the direction of the lithium diffusion pathways in the olivine crystal structure. Furthermore, the results indicate that the EG co-solvent plays an important role in tailoring the particle size, morphology, and crystal orientation of the material. Co L-edge soft X-ray absorption spectroscopy (XAS) of LiCoPO 4 are presented for the first time and confirm that the material only consists of Co 2+ . Benefiting from the unique morphology, which facilitates Li-ion conduction, electrochemical measurements deliver an initial discharge capacity of 137 mA h g -1 at 0.1 C, a remarkably stable capacity retention of 68% after 100 cycles at 0.5 C, and a specific energy density of 658 W h kg -1 based on its capacity and voltage, which is the best performance of LiCoPO 4 obtained from microwave-assisted solvothermal synthesis to date.
Realizing High-Performance Buildings
High-performance buildings (HPBs) are exceptional examples of both design and practice. Their energy footprints are small, and these are buildings that people want to work in because of their intelligent structure, operations, and coincident comfort. However, the operation of most buildings, even ones that are properly constructed and commissioned at the start, can deviate significantly from the original design intent over time, particularly due to control system overrides and growing plug and data center loads. With early planning for systems such as submetering and occupant engagement tools, operators can identify and remedy the problems. This guide is a primer for owners and owners' representatives who are pursuing HPBs. It describes processes that have been successful in the planning, procurement, and operation of HPBs with exceptional energy efficiency. Much of the guidance offered results from a series of semi-structured conference calls with a technical advisory group of 15 owners and operators of prominent HPBs in the United States. The guide provides a prescription for planning, achieving, and maintaining an HPB. Although the guide focuses on the operations stage of buildings, many of the operations practices are specified during the planning stage.
Gallium Sulfide-Single-Walled Carbon Nanotube Composites: High-Performance Anodes for Lithium-Ion Batteries
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Free-Standing Nitrogen-doped Graphene Paper as Electrodes for High-Performance Lithium/Dissolved Polysulfide Batteries
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Controllable interior structure of ZnCo 2 O 4 microspheres for high-performance lithium-ion batteries
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Three-dimensional ultrathin Ni(OH) 2 nanosheets grown on nickel foam for high-performance supercapacitors
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Controllable growth of LiMn2O4 by carbohydrate-assisted combustion synthesis for high performance Li-ion batteries
Not provided.
Utilizing Commercial Real Estate Owner and Investor Data to Analyze the Financial Performance of Energy Efficient, High-Performance Office Buildings
Evidence has shown that owning and operating energy-efficient, high-performance, “green” properties results in multiple benefits including lower utility bills, higher rents, improved occupancy, and greater net operating income. However, it is difficult to isolate and control moderating factors to identify the specific drivers behind improved financial performance and value to investors that results from sustainability in real estate. DOE is interested in facilitating deeper investigation of the correlation between energy efficiency and financial performance, reducing data acquisition and matching challenges, and developing a stronger understanding of how sustainable design and energy efficiency impact value. DOE commissioned this pilot study to test the logistical and empirical procedures required to establish a Commercial Real Estate Data Aggregation & Trends Analysis lab, determine the potential benefits available through the lab, and contribute to the existing body of evidence in this field.