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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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Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Autumn Gardens Apartment Complex and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on The Century Center and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on College of Southern Idaho and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Coveyou Scenic Farm and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Dallas-Fort Worth U.S. 287 Bridge and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Delta Electronics and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Epic Systems Corporation and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Greensburg, Kansas, City Hall and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Marine Corps Logistics Base-Albany and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Medford Site Veterans Home and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Montana State University and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Geothermal heat pumps can be great alternatives to air conditioners and furnaces, and require less electricity to run. This case study focuses on Norton Commons, Kentucky and is part of a series: https://www.energy.gov/eere/geothermal/geothermal-heat-pump-case-studies.
Class B Materials Code Case to include: FY25 - High temperature design methodology, overview of ASME Section III (Division 5), Design for elevated temperature service, Goal to address current gaps, evaluation of proposed rules, allowable stress development, Class A materials (existing ASME approach), variable confidence index, data extrapolation, bounding value for SEE, and next steps.
Abstract Developing high‐performance donor polymers is important for nonfullerene organic solar cells (NF‐OSCs), as state‐of‐the‐art nonfullerene acceptors can only perform well if they are coupled with a matching donor with suitable energy levels. However, there are very limited choices of donor polymers for NF‐OSCs, and the most commonly used ones are polymers named PM6 and PM7, which suffer from several problems. First, the performance of these polymers (particularly PM7) relies on precise control of their molecular weights. Also, their optimal morphology is extremely sensitive to any structural modification. In this work, a family of donor polymers is developed based on a random polymerization strategy. These polymers can achieve well‐controlled morphology and high‐performance with a variety of chemical structures and molecular weights. The polymer donors are D–A1–D–A2‐type random copolymers in which the D and A1 units are monomers originating from PM6 or PM7, while the A2 unit comprises an electron‐deficient core flanked by two thiophene rings with branched alkyl chains. Consequently, multiple cases of highly efficient NF‐OSCs are achieved with efficiencies between 16.0% and 17.1%. As the electron‐deficient cores can be changed to many other structural units, the strategy can easily expand the choices of high‐performance donor polymers for NF‐OSCs.
Premise Recent advances in generating large‐scale phylogenies enable broad‐scale estimation of species diversification. These now common approaches typically are characterized by (1) incomplete species coverage without explicit sampling methodologies and/or (2) sparse backbone representation, and usually rely on presumed phylogenetic placements to account for species without molecular data. We used empirical examples to examine the effects of incomplete sampling on diversification estimation and provide constructive suggestions to ecologists and evolutionary biologists based on those results. Methods We used a supermatrix for rosids and one well‐sampled subclade (Cucurbitaceae) as empirical case studies. We compared results using these large phylogenies with those based on a previously inferred, smaller supermatrix and on a synthetic tree resource with complete taxonomic coverage. Finally, we simulated random and representative taxon sampling and explored the impact of sampling on three commonly used methods, both parametric (RPANDA and BAMM) and semiparametric (DR). Results We found that the impact of sampling on diversification estimates was idiosyncratic and often strong. Compared to full empirical sampling, representative and random sampling schemes either depressed or inflated speciation rates, depending on methods and sampling schemes. No method was entirely robust to poor sampling, but BAMM was least sensitive to moderate levels of missing taxa. Conclusions We suggest caution against uncritical modeling of missing taxa using taxonomic data for poorly sampled trees and in the use of summary backbone trees and other data sets with high representative bias, and we stress the importance of explicit sampling methodologies in macroevolutionary studies.
As advances in digital engineering continue to push the technological boundaries, digital twin (DT) visualizations for diagnostics and safeguards advancement become much more feasible and practical. DTs generate large and complex data streams that require effective user interfaces to provide monitoring and diagnostic capabilities. Unfortunately, while these frameworks exist, there is not much research on the systematic documentation of human–computer interaction (HCI) for DT visualization. This work presents a dual-mode visualization methodology (two dimensional [2D] graphical user interface dashboard and 3D mixed reality) designed to support diagnostic tasks in DT systems and building on a validated framework and applying established HCI principles. The methodology is demonstrated through a case study of aqueous processing at Idaho National Laboratory, using experimental data from the chemical solvent extraction runs. Our interfaces display real-time alerts and monitoring to inform users of safeguards anomalies. The interfaces use immersive 3D mixed-reality visualization for further system and experiment investigation. This work demonstrates how the systematic application of HCI principles can inform DT visualization design for diagnostic and safeguards applications. While formal user evaluation studies remain as future work, this paper documents the systematic design methodology and demonstrates a proof-of-concept implementation.
The electronic structures of charged point defects influence electrical and optical properties of semiconductors. Understanding the orbital interactions responsible for the electronic structures of defects therefore promotes a chemical intuition for defect-driven mechanisms in semiconductors. In this tutorial, we discuss a molecular orbital theory-based framework for understanding defect-induced electronic states based on local chemical interactions between the defect and the atoms surrounding the defect site. By using Mg 2 Si as a case study, we show how both the chemical interactions and molecular orbitals (i. e., wave functions) responsible for the charge state(s) of a defect can be understood from the bonding symmetry of the defect site. We anticipate that a chemistry-based perspective of charged defects will enrich defect engineering efforts for electronic and optical materials.
Abstract Despite immense resources directed towards habitat restoration, recovering fish populations remains a daunting and perplexing issue. In 2015, recommendations for a comprehensive approach to habitat restoration in the Columbia River basin were published in Fisheries, which included elements of landscape ecology and resilience, broad public support, governance for collaboration and integration, and capacity for learning and adaptation. Using the Grande Ronde River basin as a case study, we convened a working group consisting of local restoration practitioners, managers, and researchers involved in habitat restoration research, monitoring, and evaluation to assess progress towards meeting these recommendations. We concluded that partnerships and collaborations in governance have been formed and research using a landscape perspective has been integrated into decision making, but efforts would benefit from gaining broader public support, formalizing an adaptive management strategy, and defining objectives and indicators for biological and ecological diversity. Continued progress will require consistent policy and funding support from the broader region. We envision this self-assessment at the 5-year milestone would be helpful to other groups facing similar challenges.