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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 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

SBIR Phase I Final Technical Report FAST AND DENSE OXIDE GLASS FOR HEP Award Number DE-SC0024589 Program Manager Dr. Helmut Marsiske Prepared for U.S. Department of Energy, Office of Science, SC-1 For the Period July 10, 2023 – April 9, 2024 Report Date April 26th, 2024. Submitted by Lakshmi Soundara Pandian, Ph.D., Principal Investigator Report Contributors: Dr. Lakshmi Soundara Pandian, Dr. Pijush Bhattacharya, Mr. Jared Schott, Dr. Jarek Glodo RMD Dr. Renyuan Zhu, Caltech Dr. Rastgo Hawrami, XI Radiation Monitoring Devices, Inc. 44 Hunt Street, Watertown, MA 02472

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Soundara Pandian, Lakshmi↗
DOE OSTI2024

DOE Phase II Final Technical Report Bright Electron Source for X-ray Free Electron Lasers Award Number DE-SC0020607 Prepared for U.S. Department of Energy, Office of Science, SC-1 For the Period May 3, 2021 – August 2, 2024 Report Date November 25, 2024 Submitted by Harish B. Bhandari, Ph.D., Principal Investigator Report Contributors Dr. Oleg Maksimov, RMD Inc. Dr. Bryan Rachmilowitz, RMD Inc. Dr. Jared Maxson, Cornell University Dr. Hisato Yamaguchi, LANL

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Bhandari, Harish↗
DOE OSTI2024

SBIR Phase I Final Technical Report MODULAR NEUTRON DETECTOR ARRAY FOR PROTEIN CRYSTALLOGRAPHY BEAM LINES Award Number DE-SC0024828 Prepared for U.S. Department of Energy, Office of Science, SC-1 For the Period July 22, 2024 – April 21, 2025 Report Date November 22, 2024 Submitted by Vivek V. Nagarkar, Ph.D., Principal Investigator Report Contributors Mr. Nicholas Anastasi, Dr. Charles Sosa, Dr. Jun Wang, Dr. Lakshmi Soundara Pandian and Dr. Vivek V. Nagarkar

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Nagarkar, Vivek V.↗
NASA NTRS1986

Far-infrared and radio observations of DR 6, DR 7, and DR 22

Far-infrared maps are presented for three young H II regions in the Cygnus X region. DR 6 and 7 were mapped in the wavelength band from 40 to 250 microns at 1 arcmin resolution, while DR 22 was mapped in the same band and also at 100-250 microns, providing dust temperature and optical depth information. New VLA maps of these sources are also presented. It is concluded that DR 6 and 7 are powered by clusters of late O or early B type stars, with ages 100,000 yr or less, while DR 22 appears to be produced by a single O6 ZAMS star. Existing (C-12)O maps suggest that the formation of these objects occurred near the edges of molecular clouds.

Odenwald, S.↗
NASA NTRS1990

Multiwavelength observations of two B-star nurseries - DR 15 and DR 20

New observations of DR 15 and 20 are reported as part of a study of compact H II regions in the Cyg X region. The radio and FIR data for these objects, when combined with (C-12)O maps, IRAS imagery, and optical photographs, provide new insights into the structure of this complex region and the nature of the star-formation process there. The observations show that DR 15 may consist of one or two B0 ZAMS stars whose H I regions have formed a low-density cavity within a molecular cloud. DR 20 appears to be a young OB cluster. The cluster is dominated by an O5.5 ZAMS star and also contains an approximately 3500-yr-old B0 star appearing as a compact H II region, along with weak FIR sources that may be B0-star candidates.

Odenwald, S. F.↗
DOE OSTI2022

Online distributed price-based control of DR resources with competitive guarantees

Demand response (DR) of building HVAC load can provide crucial demand-side flexibility for the future smart grid. Compared to direct load control, price-based control can respect the customers’ autonomy and privacy. However, it is challenging for price-based control to attain provable performance guarantees under future uncertainty. In this paper, we propose a framework for a utility to perform price-based control of flexible building load within the utility’s service area, in order to attain competitive performance guarantees in terms of controlling the system peak demand under future uncertainty. By adopting a two-step approach, our online price-based control solution can attain a provable competitive ratio for all possible realizations within a given uncertainty set. Simulation experiments demonstrate that, with a robustification procedure, our solution can perform well not only for worst-case inputs, but also for average-case inputs.

24 POWER TRANSMISSION AND DISTRIBUTION↗
DOE OSTI2025

SBIR Phase I Final Technical Report LOW-COST, LIGHTWEIGHT DOPED POLYMER COATINGS FOR MICROELECTRONICS VIA 3D PRINTING Award Number DE-SC0025167 Prepared for U.S. Department of Energy, Office of Science, SC-1 For the Period July 22, 2024 – April 21, 2025 Report Date May 5, 2025 Submitted by Jun Wang, Ph.D., Principal Investigator Report Contributors Dr. Jun Wang, Dr. Charles Sosa

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Wang, Jun [Radiation Monitoring Devices, Inc., Wat↗
DOE OSTI2016

Assessment of DR-55 as a Drop-In Replacement for R-410A

R410A has no ozone depletion potential (ODP), and is the most commonly used refrigerant in vapor compression systems for space cooling and heating applications. However, it has significant global warming potential with GWP higher than 1900. To mitigate the global warming effect, industry and research institutes are actively pursuing a replacement for R-410A with the following attributes, much lower GWP along with similar or higher efficiency and capacity. DR-55 (aka R452B) is a design-compatible refrigerant replacement for R-410A. It decreases the GWP by 70%, and has lower working pressure, comparable discharge temperature, and uses the same lubricant, tubing, and valves. In this study, we experimentally evaluated the performance of DR-55 as a drop-in replacement for R-410A in a high efficiency rooftop air conditioning unit. The experimental results demonstrated that DR-55 led to 5% higher efficiency at the working conditions of Integrated Energy Efficiency Rating (IEER). DR-55 also showed significantly better high ambient performance from 95 F to 125 F. In addition to the experimental study, we used the DOE/ORNL Heat Pump Design Model to model the RTU using R-410A and DR-55, respectively. The model results were compared to the laboratory measurements. The model validation demonstrates that the refrigerant heat transfer and pressure drop correlations, developed for conventional refrigerants like R-410A, are usable for DR-55. Also, a converted compressor model for DR-55, i.e. reducing volumetric and isentropic efficiencies as a function of the suction and discharge pressures from an R-410A compressor map can predict the compressor mass flow rate and power accurately.

DR-55↗
NASA NTRS2017

Renin-Angiotensin System (RAS) in Hematopoietic Stem/Progenitor Cells (HS/PC) Predicts Vaso-Reparative Dysfunction and Progression of Diabetic Retinopathy (DR)

Purpose: We tested the hypothesis that loss of angiotensin converting enzyme 2 (ACE2) within diabetic HS/PCs (Hematopoietic Stem/Progenitor Cells) would be detrimental to HS/PC reparative function, and alter their ability to contribute to vascular remodeling in human subjects and rodent models of DR (Diabetic Retinopathy). Methods: Subjects (n52) were recruited as controls (n13) or diabetics (n39) with either no DR, mild non-proliferative DR (NPDR), moderate NPDR, severe NPDR or proliferative DR (PDR). Fluorescein angiograms were analyzed using Vessel Generation Analysis (VESGEN) software in a cohort of subjects. CD34+ HS/PCs were isolated from peripheral blood. RAS (Renin-Angiotensin System) gene expression and migration was measured. Diabetic ACE2 knockout (KO)C57BL6-Ins2 (Akita) mice at 3, 6 and 9 months of diabetes were compared to age-matched controls. Bone marrow HS/PC populations were analyzed by flow cytometry and migration and proliferation studies performed. Results: ACE2 gene expression in human CD34+ cells from diabetics without DR was increased compared to controls (p0.0437). Mas receptor mRNA was also increased in diabetics without DR, but reduced with the onset of NPDR (p0.0002), suggesting a loss of compensation. DR was associated with CD34+ cell migratory dysfunction. By VESGEN analysis, vessel density measured by several confirming parameters in early NPDR (n3) was greater than in normal retina (n6) in both arteries and veins, which suggests active retinal remodeling. ACE2KO-Akita and Akita cohorts showed reduced retinal thickness by OCT (Optical Coherence Tomography) at 9 months of diabetes. Absence of ACE2 in 9-month Akita mice led to an accelerated increase in acellular capillaries compared to diabetic alone. Electroretinogram (ERG) in ACE2KO-Akita mice resulted in persistent deterioration of the neural retina. Reparative function studies showed that ACE2KO exacerbated diabetes-induced impairment of LK (Low Potassium) cell migration and proliferative functions as early as 3-month of diabetes (p0.0019). Conclusions: Retinopathy and adverse vascular remodeling in subjects with diabetes was associated with a loss of the protective arm of RAS in HS/PCs. Loss of ACE2 exacerbated vascular dysfunction in diabetic mice.

retina↗
DOE OSTI2018

NLRP1 deficiency attenuates diabetic retinopathy (DR) in mice through suppressing inflammation response

Highlights: • NLRP1 expression was increased in retina of diabetic mice. • NLRP1 deletion attenuates STZ-induced diabetic retinopathy. • Knockout of NLRP1 reduces inflammation and alleviates diabetic retinopathy in STZ mice. • Suppression of NLRP1 restrains inflammation in high fructose-incubated retinal ganglion cells. Diabetic retinopathy (DR) is the common cause of diabetic vascular complications. The NOD-like receptor (NLR) family, pyrin domain containing 1 (NLRP1), also known as NALP1, inflammasome is the first member of the NLR family to be discovered, playing an important role in inflammatory response. However, its effect on DR development has not been reported. In the study, the wild type (WT) and NLRP1{sup −/−} mice were injected with streptozotocin (STZ) to induce DR. The results indicated that NLRP1{sup −/−} significantly increased bodyweight reduction and decreased blood glucose levels induced by STZ. WT/DR mice exhibited higher levels of NLRP1 in retinas. NLRP1{sup −/−} ameliorated retinal abnormalities in DR mice using H&E staining. In addition, attenuated avascular areas and neovascular tufts were also observed in NLRP1{sup −/−}/DR mice. The levels of pro-inflammatory cytokines in serum and retinas were highly induced in WT/DR mice, whereas being markedly reduced by NLRP1{sup −/−}. In addition, vascular endothelial growth factor (VEGF) and Iba1 expressions induced by STZ in serum or retinas were significantly down-regulated in NLRP1{sup −/−}/DR mice. Consistently, NLRP1{sup −/−} attenuated ASC and Caspase-1 expressions in retinas of DR mice. Compared to WT/DR group, NLRP1{sup −/−} markedly decreased retina p-nuclear factor-κB (NF-κB), interleukin-1β (IL-1β) and IL-18 levels. And similar results were confirmed in vitro that suppressing NLRP1/ASC inflammasome ameliorated inflammatory response in fructose-treated retinal ganglion cells. The results above indicated that the modulation of NLRP1 inflammasome might be a promising strategy for DR therapy.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

Modular adjuvant-free pan-HLA-DR-immunotargeting subunit vaccine against SARS-CoV-2 elicits broad sarbecovirus-neutralizing antibody responses

Subunit vaccines typically require co-administration with an adjuvant to elicit protective immunity, adding development hurdles that can impede rapid pandemic responses. To circumvent the need for adjuvant in a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) subunit vaccine, we engineer a thermostable immunotargeting vaccine (ITV) that leverages the pan-HLA-DR monoclonal antibody 44H10 to deliver the viral spike protein receptor-binding domain (RBD) to antigen-presenting cells. X-ray crystallography shows that 44H10 binds to a conserved epitope on HLA-DR, providing the basis for its broad HLA-DR reactivity. Adjuvant-free ITV immunization in rabbits and ferrets induces robust anti-RBD antibody responses that neutralize SARS-CoV-2 variants of concern and protect recipients from SARS-CoV-2 challenge. We demonstrate that the modular nature of the ITV scaffold with respect to helper T cell epitopes and diverse RBD antigens facilitates broad sarbecovirus neutralization. Our findings support anti-HLA-DR immunotargeting as an effective means to induce strong antibody responses to subunit antigens without requiring an adjuvant.

60 APPLIED LIFE SCIENCES↗
DOE OSTI2023

At the interfaces of the hydrologic sciences: Connecting water, elements, ecosystems, and people through the major contributions of Dr. Emily Bernhardt

Here, in this paper, we describe the major contributions of Professor Emily Bernhardt to the hydrologic sciences. Dr. Bernhardt’s work addresses how carbon, nutrient, and contaminant dynamics respond to a wide range of environmental perturbations that alter hydrologic dynamics within and connectivity among ecosystems. Her research leverages intensive and extensive field sampling, experimental manipulations, macroscale data harmonization and exploration, and continental to global-scale synthesis activities to uncover key drivers and patterns of the impacts human perturbations have on water and elemental cycles. Dr. Bernhardt’s research program is defined by her ability to ask questions and use approaches that explicitly consider connectivity and interfaces in a variety of ways. Here, we highlight significant contributions from Dr. Bernhardt’s work, organized by connectivity, interfaces, and interactions among and across (1) elemental cycles, (2) ecosystems, (3) watersheds, (4) scales, and (5) disciplines. We conclude with a section on Dr. Bernhardt’s impact on the hydrologic sciences and beyond through her exceptional dedication to mentorship, engagement, and service.

58 GEOSCIENCES↗
DOE OSTI2024

Celebrating Notable Advances in Compound Semiconductors: A Tribute to Dr. Wladyslaw Walukiewicz

The Special Topic "Native Defects, Impurities and the Electronic Structure of Compound Semiconductors" is dedicated to Dr. Wladyslaw (Wladek) Walukiewicz, our esteemed colleague who passed away on November 9, 2022, at age 76. It is not often that a scientist is able to profoundly impact more than one to two scientific topics in their lifetime. Dr. Walukiewicz, a condensed matter theorist by training, arguably did that for at least four. While his scientific accomplishments tell the story of a successful career and valuable contributions, it does not convey the entire story. For the rest, one has only to look at the community of researchers he brought together across the globe. Dr. Walukiewicz conducted his work with curiosity, integrity, and respect for others that elevated those around him. Here, we pay tribute to Dr. Walukiewicz's ideas and the legacy he leaves behind.

defects↗
NASA NTRS2001

The Research of Dr. Joanne Simpson: Fifty Years Investigating Hurricanes, Tropical Clouds and Cloud Systems

This AMS Meteorological Monographs is dedicated to Dr. Joanne Simpson for her many pioneering research efforts in tropical meteorology during her fifty-year career. Dr. Simpson's major areas of scientific research involved the "hot tower" hypothesis and its role in hurricanes, structure and maintenance of trade winds, air-sea interaction, and observations and the mechanism for hurricanes and waterspouts. She was also a pioneer in cloud modeling with the first one-dimensional model and had the first cumulus model on a computer. She also played a major role in planning and leading observational experiments on convective cloud systems. The launch of the Tropical Rainfall Measuring Mission (TRMM) satellite, a joint U.S.-Japan project, in November of 1997 made it possible for quantitative measurements of tropical rainfall to be obtained on a continuous basis over the entire global tropics. Dr. Simpson was the TRAM Project Scientist from 1986 until its launch in 1997. Her efforts during this crucial period ensured that the mission was both well planned scientifically and well engineered as well as within budget. In this paper, Dr. J. Simpson's nine specific accomplishments during her fifty-year career: (1) hot tower hypothesis, (2) hurricanes, (3) airflow and clouds over heated islands, (4) cloud models, (5) trade winds and their role in cumulus development, (6) air-sea interaction, (7) cloud-cloud interactions and mergers, (8) waterspouts, and (9) TRMM science, will be described and discussed.

Tao, W. -K.↗
NASA NTRSDate not supplied

Dissociative Recombination (DR) and Associative Ionization (AI) Cross Section Calculations for the NO+ + e yields N + O (2D+3P, 2P+3P, and 2D+1D) Reaction for Atmospheric Entry Modeling

During entry of a space craft into Earth atmosphere, the flow surrounding the vehicle becomes partially ionized leading to significant cation and free-electron production. Subsequently, electron impact excitation and dissociation form radiating excited state species that contribute to the heat load on the vehicle. While experimental data on selected total cross sections are available, few experiments address the need for accurate AI cross sections for metastable atomic states at the high temperatures realized in atmospheric re-entry. In order to maintain desired safety margins during atmospheric entry of a space vehicle, chemical reaction models need to accurately account for this process. For the present study, we have computed vibrationally resolved cross sections for the DR of NO+ for electron energies between 0.01 to 10 eV and apply microscopic reversibility to obtain the AI cross sections and rate coefficients. For the DR cross section calculations, we use state-of-the-art MRCI potential energy curves. The resulting adiabatic potential curves are transformed to a diabatic representation, which is used in time-dependent wave packet calculations to describe the nuclear motion of the dissociating cation upon collision with an electron. Based on the wave function evolution in time, these calculations provide T-matrix and cross sections for the DR including recombination into the low energy metastable atomic states. The DR and AI rate coefficients are compared with the available experimental data.

Ewa Papajak↗
DOE OSTI2015

Purification and characterization of DR_2577 (SlpA) a major S-layer protein from Deinococcus radiodurans

The protein DR_2577 is a major Surface layer component of the radio-resistant bacterium Deinococcus radiodurans. In the present study DR_2577 has been purified and its oligomeric profile characterized by means of size exclusion chromatography and gel electrophoresis. DR_2577 was found to be organized into three hierarchical orders characterized by monomers, stable dimers formed by the occurrence of disulfide bonds, and hexamers resulting from a combination of dimers. Finally, the structural implications of these findings are discussed providing new elements for a more integrated model of this S-layer.

59 BASIC BIOLOGICAL SCIENCES↗