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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 1,009 records · Page 56
All sourcesNASA NTRSDOE OSTI
DOE OSTI2026

Preliminary Assessment for the Electric Load Shifting Potential of Integrating Thermal Energy Storage with Heat Pumps in Residential Buildings in Texas of United States

The widespread adoption of electric-driven heat pumps for heating and cooling is expected to significantly increase electric demand. Cooling electric demand will result in an increase in peak hours electric loads, placing additional strain on the grid during peak hours. This challenge, combined with the current rapidly increasing demand from data centers, exacerbates the electric demand duck curve problem. Integrating thermal energy storage (TES) with heat pump can shift electric use for heating and cooling from peak to off-peak hours of the electric grid, which can help flatten the daily electric demand profile of a building. This paper presents a novel design that integrates heat pump with TES (HP-TES), which uses phase change materials (PCM). Heat pump charges TES by melting or freezing PCM during off-peak hours when there is no thermal demand from the building. TES is then discharged (i.e., by freezing or melting PCM) during peak hours to provide a more favorable heat source or heat sink for the heat pump to meet the thermal demand of the building with lower electricity use than conventional air-source heat pumps. Computer simulations were developed to predict the performance of HP-TES applied to a typical single-family house in the US. The building-level simulation results were scaled up to preliminarily assess the aggregated impacts of deploying HP-TES across all single-family houses in Texas of the United States, including reduction of peak demand of the electric grid.

Anees, Fady [ORNL]↗
DOE OSTI2022

Development of the multi-purpose Cologne Compact Differential Plunger (CoCoDiff) for the measurement of nuclear level lifetimes with the Recoil Distance Doppler-shift method

Here, a new 3-foil plunger device, the Cologne Compact Differential (CoCoDiff) plunger has been built and commissioned. Due to its compact size, it can be used together with many different spectrometers and auxiliary detectors. As a commissioning experiment, level lifetimes of the $2^{+}_{1}$ and the $4^{+}_{1}$ excited states of 50 Cr have been measured, using the Differential Decay Curve method (DDCM). A derivation is given on how this method can be applied to a differential plunger measurement, in order to measure distances for lifetimes from two different regions of sensitivity at the same time. The commissioning experiment took place at the Cologne FN tandem accelerator, using the reaction 24 Mg( 32 S,4p2n) 50 Cr. Lifetimes, deduced from this measurement, agree well with literature values from earlier measurements.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗
DOE OSTI2021

Au and Pt Remain Unoxidized on a CeO 2 -Based Catalyst during the Water–Gas Shift Reaction

The active form of Au and Pt in CeO 2 based catalysts for the WGS reaction is an issue that although it has been widely studied remains unclear. On one hand, ionic species might be responsible of weakening the Ce-O bonds increasing the oxygen mobility and WGS activity. On the other hand, the close contact of Au or Pt atoms with CeO 2 oxygen vacancies at the metal/CeO 2 interface might provide the active sites for an efficient reaction. In this work, by using in-situ X-ray absorption spectroscopy, we demonstrate that both Au and Pt remain unoxidized during the reaction. Here, remarkable differences involving the dynamics established by both species under WGS atmospheres were recognized. For the pre-reduced Pt catalyst, an increase of the conversion coincided with a re-structuration of the Pt atoms into cuboctahedrical metallic particles without significant variations on the overall particle size. Contrary to the relatively static behavior of Pt 0 , Au 0 nanoparticles exhibited a sequence of particle splitting and agglomeration whilst maintaining a zero oxidation state, even though not being located in a metallic environment during the process. High WGS activity was obtained when Au atoms were surrounded by oxygen. The fact that Au preserves its unoxidized state indicates that the chemical interaction between Au and oxygen must be necessarily electrostatic being such electrostatic interaction fundamental for a top performance in the WGS process.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Electrochromic shift supports the membrane destabilization model of Tat-mediated transport and shows ion leakage during Sec transport

Significance Due to the transient nature of the active Tat complex, much of the knowledge available has been hard won. Electric-field-indicating absorbance transients allow investigation of transmembrane ion movement using native electric potential in thylakoids while circumventing challenges of reconstitution. Electrical behavior of transiently and/or constitutively assembled complexes suggests that Sec translocation occurs through a barrel-stave-type proteinaceous pore, while Tat translocation likely occurs through a toroidal pore. This would be the first instance of toroidal pores being exploited by a general protein translocation system. Our electrochemical analysis offers insight into how protein transport might be linked to light stimulation. Localized membrane destabilization presents a rational link between the proton motive force, membrane thinning, and Tat-mediated transport of substrates critical to photosynthesis.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2021

Natural soil microbiome variation affects spring foliar phenology with consequences for plant productivity and climate-driven range shifts

Identifying the potential for natural soil microbial communities to predictably affect complex plant traits is an important frontier in climate change research. Plant phenology varies with environmental and genetic factors, but few studies have examined if the soil microbiome interacts with plant population differentiation to affect phenology and ecosystem function. We compared soil microbial variation in a widespread tree species (Populus angustifolia) with different soil inoculum treatments in a common garden environment to test how the soil microbiome affects spring foliar phenology and subsequent biomass growth. We hypothesized and show that: 1) soil bacterial and fungal communities vary with tree conditioning from different populations and elevations, 2) this soil community variation influences patterns of foliar phenology and plant growth across populations and elevation gradients, and 3) transferring lower elevation plant genotypes to higher elevation soil communities delayed foliar phenology, thereby shortening the growing season and reducing annual biomass production. Our findings show the importance of plant-soil interactions that help shape the timing of tree foliar phenology and productivity. Here, these geographic patterns in plant population x microbiome interactions also broaden our understanding of how soil communities impact plant phenotypic variation across key climate change gradients, with consequences for ecosystem functioning.

59 BASIC BIOLOGICAL SCIENCES↗
NASA NTRS2002

Dose measurement based on threshold shift in MOSFET arrays in commercial SRAMS

A new method using an array of MOS transistors isdescribed for measuring dose absorbed from ionizingradiation. Using the array of MOSFETs in a SRAM, a direct measurement of the number of MOS cells which change as a function of applied bias on the SRAM. Since the input and output of a SRAM used as a dosimeter is completely digital, the measurement of dose is easily accessible by a remote processing system.

SRAM dosimetry microdosimetry threshold shift↗