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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 541 records · Page 30
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Compact, high-efficiency accelerators driven by low-voltage solid-state amplifiers

A compact particle accelerator can include two or more cavities disposed along an axis of the particle accelerator, each of which is coupled to two or more drivers. The accelerator can also include a power supply coupled to the two or more drivers such that a particle beam traveling along the axis is accelerated. The power supply can be an interface with a commercial power outlet, battery power, or a combination thereof depending upon the use case. Example configurations of the accelerator include hand held or mobile devices that are capable of delivering up to and greater than a 1 MeV electron beam.

Nguyen, Dinh Cong↗
DOE OSTI2021

High-efficiency oxygen reduction to hydrogen peroxide catalyzed by oxidized carbon materials

Improved electrochemical production of hydrogen peroxide is provided with a surface-oxidized carbon catalyst. The carbon can be, for example, carbon black or carbon nanotubes. The oxidation of the carbon can be performed, for example, by heating the carbon in nitric acid, or by heating the carbon in a base. The resulting carbon catalyst can have a distinctive oxygen is peak in its X-ray photoelectron spectrum.

Cui, Yi↗
DOE OSTI2021

High-efficiency optical limiter using metasurface and phase-change material

According to some aspects, a transmissive and all-dielectric optical component/limiter with great cutoff efficiency using Vanadium Dioxide (VO 2 ) as the active component is disclosed. In some embodiments, Vanadium dioxide is used for an optical limiter due to the large contrast in optical constants upon undergoing the semiconductor to metal phase transition. When triggered optically, this transition occurs within 60 fs, making the device suitable for an ultrafast laser environment. In addition, the phase transition threshold is tunable by applying stress or doping; therefore, the device cutoff intensity can be adjusted to fulfill specific requirements.

Valentine, Jason G.↗
DOE OSTI2022

Sandwich gasification process for high-efficiency conversion of carbonaceous fuels to clean syngas with zero residual carbon discharge

The present invention discloses a gasifier and/or a gasification process that provides a long, uniform temperature zone in the gasifier, regardless of the particle size, chemical composition, and moisture content of the fuel by sandwiching a reduction zones between two oxidation zones. The gasifier and/or gasification process has a char that is more energy-dense and almost devoid of moisture that affords for an additional (or char) oxidation zone with a temperature that is higher than a first oxidation zone which is closer to an evaporation and devolatilization zone. As such, the additional (or char) oxidation zone contributes to augmenting the reduction zone temperature, thereby providing a favorable dual impact in improving syngas composition and near-complete conversion of the tar.

Patel, Nikhil Manubhai↗
DOE OSTI2022

High Efficiency Travelling Wave X-Band Linac With Tunable Output Energy

We are designing a compact and efficient electron linac with 500 W of average beam power and beam energy tunable from 5 to 10 MeV. The accelerator is of travelling wave type, and has little RF power reflected back to the RF source, eliminating the need for a large, lossy isolator. The structure is powered by a compact commercial 1.7 MW 9.3 GHz magnetron. To vary the beam energy we will change the current from the triode gun. We present an analysis of the structure, which includes varying the length from 60 cm to 80 cm, and the structure type, such as constant impedance versus constant gradient.

Romero, Agustin↗
DOE OSTI2023

High efficiency translucent solar module integrated with greenhouse roof structures

A translucent solar module assembly for integration with a greenhouse having a frame with a plurality of roof supports includes a pair of brackets attachable to each of the plurality of roof supports, a bi-facial solar panel attachable to the pair of brackets, and a pair of reflector rails attachable to each of the plurality of roof supports. A dichroic reflector is attachable to the pair of reflector rails.

Pan, Wei↗
DOE OSTI2023

Sandwich gasification process for high-efficiency conversion of carbonaceous fuels to clean syngas with zero residual carbon discharge

gasifier and a gasification process provides a long, uniform temperature zone in the gasifier, regardless of the particle size, chemical composition, and moisture content of the fuel by sandwiching a reduction zones between two oxidation zones. The gasifier and gasification process produces a char that is more energy-dense and almost devoid of moisture, affording an additional (char) oxidation zone with a temperature that is higher than a first oxidation zone which is closer to an evaporation and devolatilization zone. As such, the additional (char) oxidation zone contributes to augmenting the reduction zone temperature, providing a favorable dual impact in improving syngas composition and near-complete conversion of the tar.

Patel, Nikhil Manubhai↗