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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 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Broad band tunable energy electron beam pulser

An electromagnetic mechanical pulser implements a transverse wave metallic comb stripline TWMCS kicker having inwardly opposing teeth that retards a phase velocity of an RF traveling wave to match the kinetic velocity of a continuous electron beam, causing the beam to oscillate before being chopped into pulses by an aperture. The RF phase velocity is substantially independent of RF frequency and amplitude, thereby enabling independent tuning of the electron pulse widths and repetition rate. The TWMCS further comprises an electron pulse picker (EPP) that applies a pulsed transverse electric field across the TWMCS to deflect electrons out of the beam, allowing only selected electrons and/or groups of electrons to pass through. The EPP pulses can be synchronized with the RF traveling wave and/or with a pumping trigger of a transverse electron microscope (TEM), for example to obtain dynamic TEM images in real time.

42 ENGINEERING↗
DOE OSTI2021

Molecularly tunable heterogeneous catalysts by edge functionalization of graphitic carbons

Disclosed are surface immobilized (electro)catalysts that may be prepared by a condensation reaction that generates an aromatic unit that is robust to acid and base and elevated temperatures. Among their many desirable characteristics, the catalysts are far less prone to the bimolecular deactivation pathways commonly observed for homogeneous catalysts, and may be used in solvents with a range of polarities and dielectric strengths. The catalysts are suitable for a wide array of thermal catalytic reactions (polymerization, oxidation, hydrogenation, cross-coupling etc.) and as anodes and/or cathodes in fuel cells, electrolyzers, and in batteries and supercapacitors.

Surendranath, Yogesh↗
DOE OSTI2021

Tunable metal-organic framework compositions and methods thereof

The present invention relates to a metal-organic framework composition, as well as constructs and methods thereof. In one particular example, the composition provides a platform having an emission signal in the deep red to near-infrared (NIR) region.

Sava Gallis, Dorina F.↗
DOE OSTI2021

Tunable anisotropy of co-based nanocomposites for magnetic field sensing and inductor applications

A method includes producing an amorphous precursor to a nanocomposite, performing devitrification of the amorphous precursor, forming, based on the devitrification, the nanocomposite comprising an induced magnetic anisotropy, and for a first portion of the nanocomposite, determining a desired value of a magnetic permeability of the first portion, tuning, based on the desired value, the induced magnetic anisotropy for the first portion, and adjusting, based on the tuning of the induced magnetic anisotropy of the first portion, a first magnetic permeability value of the first portion of the nanocomposite, wherein the first magnetic permeability value is different from a second magnetic permeability value for a second portion of the nanocomposite.

Leary, Alex M.↗
DOE OSTI2022

Tunable and reconfigurable atomically thin heterostructures

Heterocrystals of metal dichalcogenides and Bi 2 S 3 , Bi 2 Se 3 or Bi 2 Te 3 are presented, in which the metal dichalcogenides and Bi 2 S 3 , Bi 2 Se 3 or Bi 2 Te 3 do not largely retain their independent properties. These heterocrystals exhibit electronic and optical changes, which make them attractive for beyond-silicon electronics and optoelectronics. Particularly, these heterocrystals can be re-configured in a manner that allows bit writing and pattern drawing. Embodiments of these heterocrystals, methods of forming these heterocrystals, methods of reconfiguring the heterocrystals, information storage devices, optoelectronic circuits and photonic crystals are presented.

Vargas, Anthony↗
DOE OSTI2023

Tunable anisotropy of co-based nanocomposites for magnetic field sensing and inductor applications

A method includes producing an amorphous precursor to a nanocomposite, the amorphous precursor comprising a material that is substantially without crystals not exceeding 20% volume fraction; performing devitrification of the amorphous precursor, wherein the devitrification comprises a process of crystallization; forming, based on the devitrification, the nanocomposite with nano-crystals that contains an induced magnetic anisotropy; tuning, based on one or more of composition, temperature, configuration, and magnitude of stress applied during annealing and modification, the magnetic anisotropy of the nanocomposite; and adjusting, based on the tuned magnetic anisotropy, a magnetic permeability of the nanocomposite.

Leary, Alex M.↗