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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 919 records · Page 51
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Guide de base pour l'energie solaire hors reseau en Haiti

This training lends insight into key information and concepts for off-grid solar in Haiti, building foundational knowledge and an ability to catalyze interest in off-grid solar for rural electrification in Haiti. This self-paced course is offered in both English and French and covers a variety of topics related to energy access in Haiti including off-grid solar products, market potential in Haiti, supply and demand side considerations, system design, installation and maintenance, off-grid solar business models, financial modeling, gender and energy access, productive use of energy, and climate adaptation. The training is intended for university students, government partners, NGOs, funders, development partners, professionals, and more. No prior knowledge of off-grid solar or Haiti is required to benefit from this training. See NREL/PR-7A40-88999 for the English translation of this document.

ENERGY PLANNING, POLICY, AND ECONOMY,SOLAR ENERGY↗
DOE OSTI2024

Foundations of Off-Grid Solar in Haiti: 11. Climate Adaptation and Resilience

This training lends insight into key information and concepts for off-grid solar in Haiti, building foundational knowledge and an ability to catalyze interest in off-grid solar for rural electrification in Haiti. This self-paced course is offered in both English and French and covers a variety of topics related to energy access in Haiti including off-grid solar products, market potential in Haiti, supply and demand side considerations, system design, installation and maintenance, off-grid solar business models, financial modeling, gender and energy access, productive use of energy, and climate adaptation. The training is intended for university students, government partners, NGOs, funders, development partners, professionals, and more. No prior knowledge of off-grid solar or Haiti is required to benefit from this training. See NREL/PR-7A40-89265 for the French translation of this document.

adaptation↗
DOE OSTI2024

Foundations of Off-Grid Solar in Haiti

This training lends insight into key information and concepts for off-grid solar in Haiti, building foundational knowledge and an ability to catalyze interest in off-grid solar for rural electrification in Haiti. This self-paced course is offered in both English and French and covers a variety of topics related to energy access in Haiti including off-grid solar products, market potential in Haiti, supply and demand side considerations, system design, installation and maintenance, off-grid solar business models, financial modeling, gender and energy access, productive use of energy, and climate adaptation. The training is intended for university students, government partners, NGOs, funders, development partners, professionals, and more. No prior knowledge of off-grid solar or Haiti is required to benefit from this training. See NREL/PR-7A40-89000 for the French translation of this document.

ENERGY PLANNING, POLICY, AND ECONOMY,SOLAR ENERGY↗
DOE OSTI2024

Foundations of Off-Grid Solar in Haiti: 3. Market Potential for Off-Grid Solar in Haiti

This training lends insight into key information and concepts for off-grid solar in Haiti, building foundational knowledge and an ability to catalyze interest in off-grid solar for rural electrification in Haiti. This self-paced course is offered in both English and French and covers a variety of topics related to energy access in Haiti including off-grid solar products, market potential in Haiti, supply and demand side considerations, system design, installation and maintenance, off-grid solar business models, financial modeling, gender and energy access, productive use of energy, and climate adaptation. The training is intended for university students, government partners, NGOs, funders, development partners, professionals, and more. No prior knowledge of off-grid solar or Haiti is required to benefit from this training. See NREL/PR-7A40-89257 for the French translation of this document.

ENERGY PLANNING, POLICY, AND ECONOMY,SOLAR ENERGY↗
DOE OSTI2017

Setaria Comes of Age: Meeting Report on the Second International Setaria Genetics Conference

Setaria viridis is an emerging model for cereal and bioenergy grasses because of its short stature, rapid life cycle and expanding genetic and genomic toolkits. Its close phylogenetic relationship with economically important crops such as maize and sorghum positions Setaria as an ideal model system for accelerating discovery and characterization of crop genes that control agronomically important traits. The Second International Setaria Genetics Conference was held on March 6–8, 2017 at the Donald Danforth Plant Science Center, St. Louis, MO, United States to discuss recent technological breakthroughs and research directions in Setaria (presentation abstracts can be downloaded at https://www.brutnelllab.org/setaria). Here, we highlight topics presented in the conference including inflorescence architecture, C 4 photosynthesis and abiotic stress. Genetic and genomic toolsets including germplasm, mutant populations, transformation and gene editing technologies are also discussed. Since the last meeting in 2014, the Setaria community has matured greatly in the quality of research being conducted. Outreach and increased communication with maize and other plant communities will allow broader adoption of Setaria as a model system to translate fundamental discovery research to crop improvement.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2011

Clustering aspects in nuclear structure functions

For understanding an anomalous nuclear effect experimentally observed for the beryllium-9 nucleus at the Thomas Jefferson National Accelerator Facility, clustering aspects are studied in structure functions of deep inelastic lepton-nucleus scattering by using momentum distributions calculated in antisymmetrized (or fermionic) molecular dynamics (AMD) and also in a simple shell model for comparison. According to AMD, the {sup 9}Be nucleus consists of two {alpha}-like clusters with a surrounding neutron. The clustering produces high-momentum components in nuclear wave functions, which affects nuclear modifications of the structure functions. We investigated whether clustering features could appear in the structure function F{sub 2} of {sup 9}Be along with studies for other light nuclei. We found that nuclear modifications of F{sub 2} are similar in both AMD and shell models within our simple convolution description although there are slight differences in {sup 9}Be. It indicates that the anomalous {sup 9}Be result should be explained by a different mechanism from the nuclear binding and Fermi motion. If nuclear-modification slopes d(F{sub 2}{sup A}/F{sub 2}{sup D})/dx are shown by the maximum local densities, the {sup 9}Be anomaly can be explained by the AMD picture, namely by the clustering structure, whereas it certainly cannot be described in the simple shell model. This fact suggests that the large nuclear modification in {sup 9}Be should be explained by large densities in the clusters. For example, internal nucleon structure could be modified in the high-density clusters. The clustering aspect of nuclear structure functions is an unexplored topic which is interesting for future investigations.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2011

Trend of the research on construction and demolition waste management

Research interests in addressing construction and demolition (C and D) waste management issues have resulted in a large amount of publications during the last decade. This study demonstrates that there is no systematic examination on the research development in literature in the discipline of C and D waste management. This study presents the latest research trend in the discipline through analyzing the publications from 2000 to 2009 in eight major international journals. The analysis is conducted on the number of papers published annually, main authors' contributions, research methods and data analysis methods adopted, and research topics covered. The results exhibit an increasing research interest in C and D waste management in recent years. Researchers from developed economies have contributed significantly to the development of the research in the discipline. Some developing countries such as Malaysia and China have also been making good efforts in promoting C and D waste management research. The findings from this study also indicate that survey and case study are major methods for data collection, and the data are mostly processed through descriptive analysis. It is anticipated that more future studies on C and D waste management will be led by researchers from developing economies, where construction works will remain their major economic activities. On the other hand, more sophisticated modeling and simulating techniques have been used effectively in a number of studies on C and D waste management research, and this is considered a major methodology for future research in the discipline. C and D waste management will continue to be a hot research topic in the future, in particularly, the importance of human factors in C and D waste management has emerged as a new challenging topic.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2020

Assessment of reverse gun taylor cylinder experimental configuration

Experimental efforts for Taylor-anvil impact tests have often been limited to near room temperature. The ‘Reverse Gun’ method proposed by Gust in 1982 allows for the Taylor impact specimen to be uniformly heated without temperature losses before impact. Through the use of finite element analysis, we explore two topics in this work. First, we examine whether the reverse gun experimental configuration is comparable to the traditional Taylor-anvil setup. Second, we assess the accuracy of several commonly employed flow strength models in terms of their ability to predict the reverse gun experimental results which involve dynamic loading conditions and complex thermo-mechanical coupling. The reverse gun simulations are performed for tantalum targets at initial temperatures in the range 295 K to 1295 K and velocities from 135 m/s to 242 m/s. We show that with suitable care in the modeling of the preheated reverse gun experiments one can make valuable assessments of flow strength models. Given the conditions explored, these observations probe the thermal softening, strain hardening, and strain rate sensitivity of the material.

42 ENGINEERING↗
DOE OSTI2018

A coevolution-guided model for the rotor of the bacterial flagellar motor

The Salmonella typhimurium trans-membrane FliF MS ring templates assembly of the rotary bacterial fagellar motor, which also contains a cytoplasmic C-ring. A full-frame fusion of FliF with the rotor protein FliG assembles rings in non-motile expression hosts. 3D electron microscopy reconstructions of these FliFFliG rings show three high electron-density sub-volumes. 3D-classifcation revealed heterogeneity of the assigned cytoplasmic volume consistent with FliG lability. We used residue coevolution to construct homodimer building blocks for ring assembly, with X-ray crystal structures from other species and injectisome analogs. The coevolution signal validates folds and, importantly, indicates strong homodimer contacts for three ring building motifs (RBMs), initially identified in injectisome structures. It also indicates that the cofolded domains of the FliG N-terminal domain (FliG_N) with embedded α-helical FliF carboxy-terminal tail homo-oligomerize. The FliG middle and C-terminal domains (FliG_MC) have a weak signal for homo-dimerization but have coevolved to conserve their stacking contact. The homodimers and their ring models ft well into the 3D reconstruction. We hypothesize that a stable FliF periplasmic hub provides a platform for FliG ring self-assembly, but the FliG_MC ring has only limited stability without the C-ring. We also present a mechanical model for torque transmission in the FliFFliG ring.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2017

Cooperative Interactions between Different Classes of Disordered Proteins Play a Functional Role in the Nuclear Pore Complex of Baker’s Yeast

Nucleocytoplasmic transport is highly selective, efficient, and is regulated by a poorly understood mechanism involving hundreds of disordered FG nucleoporin proteins (FG nups) lining the inside wall of the nuclear pore complex (NPC). Previous research has concluded that FG nups in Baker’s yeast (S. cerevisiae) are present in a bimodal distribution, with the “Forest Model” classifying FG nups as either di-block polymer like “trees” or single-block polymer like “shrubs”. Using a combination of coarse-grained modeling and polymer brush modeling, the function of the di-block FG nups has previously been hypothesized in the Di-block Copolymer Brush Gate (DCBG) model to form a higher-order polymer brush architecture which can open and close to regulate transport across the NPC. In this manuscript we work to extend the original DCBG model by first performing coarse grained simulations of the single-block FG nups which confirm that they have a single block polymer structure rather than the di-block structure of tree nups. Our molecular simulations also demonstrate that these single-block FG nups are likely cohesive, compact, collapsed coil polymers, implying that these FG nups are generally localized to their grafting location within the NPC. We find that adding a layer of single-block FG nups to the DCBG model increases the range of cargo sizes which are able to translocate the pore through a cooperative effect involving single-block and di-block FG nups. This effect can explain the puzzling connection between single-block FG nup deletion mutants in S. cerevisiae and the resulting failure of certain large cargo transport through the NPC. Facilitation of large cargo transport via single-block and di-block FG nup cooperativity in the nuclear pore could provide a model mechanism for designing future biomimetic pores of greater applicability.

Science & Technology - Other Topics↗
DOE OSTI2011

Design Considerations for Large Mass Ultra-Low Background Experiments

Summary The objective of this document is to present the designers of the next generation of large-mass, ultra-low background experiments with lessons learned and design strategies from previous experimental work. Design issues divided by topic into mechanical, thermal and electrical requirements are addressed. Large mass low-background experiments have been recognized by the scientific community as appropriate tools to aid in the refinement of the standard model. The design of these experiments is very costly and a rigorous engineering review is required for their success. The extreme conditions that the components of the experiment must withstand (heavy shielding, vacuum/pressure and temperature gradients), in combination with unprecedented noise levels, necessitate engineering guidance to support quality construction and safe operating conditions. Physical properties and analytical results of typical construction materials are presented. Design considerations for achieving ultra-low-noise data acquisition systems are addressed. Five large-mass, low-background conceptual designs for the one-tonne scale germanium experiment are proposed and analyzed. The result is a series of recommendations for future experiments engineering and for the Majorana simulation task group to evaluate the different design approaches.

1TGe One-tonne 76Ge neutrinoless double beta-decay↗