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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1922

The R-38 Catastrophe and the Mechanics of Rigid Airship Construction

An airship frame may be regarded as a rigid girder subjected to a number of forces which, according to their nature, may be classified as follows: weight or loads (force of gravity); lifting forces (aero-static); accelerations (dynamic). These forces must be in equilibrium in the three most important cases during flight: 1) when the airship is floating (aerostatic problem); 2) when flying without acceleration (aerodynamic problem). 3) When under the influence of any accelerating force (dynamic problem). This report will briefly discuss each of these cases in regard to the R-38 airship accident.

AIRSHIPS - R-38 - ACCIDENTS (BRIT )↗
DOE OSTI2025

Rigid Supramolecular Aramid Nanotubes as Catalyst Supports

Solution‐phase heterogeneous catalysts benefit from nanoscale dimensions, which maximize specific surface area and enhance catalytic activity. However, the ease of recovering such nanocatalysts depends on the design of the support materials, which are often particle‐like. Rigid 1D nanomaterials are proposed as supports that can enhance separability while offering high volumetric specific surface area for greater catalyst loading and activity. Here, aramid amphiphiles (AAs) are designed to spontaneously self‐assemble in water into high‐aspect‐ratio supramolecular nanotubes with tunable surface chemistry. These AA nanotubes exhibit high persistence lengths (P = 750 ± 340 µm) and mechanical stiffnesses (3 N/m). Incorporating surface thiol groups enables immobilization of catalytic gold nanoparticles. The resulting AA nanotube‐gold nanoparticle complexes exhibit high catalytic activity, efficient recoverability via simple microfiltration, and sustained reusability over ten reaction cycles. This study demonstrates the utility of molecular self‐assembled 1D nanomaterials as versatile scaffolds for the reuse and recovery of nanoscale catalysts.

1D nanomaterials↗
DOE OSTI2024

Transfer of Millimeter‐Scale Strained Multiferroic Epitaxial Thin Films on Rigid Substrates via an Epoxy Method Producing Magnetic Property Enhancement

The demonstration of epitaxial thin film transfer has enormous potential for thin film devices free from the traditional substrate epitaxy limitations. However, large-area continuous film transfer remains a challenge for the commonly reported polymer-based transfer methods due to bending and cracking during transfer, especially for highly strained epitaxial thin films. In this work, a new epoxy-based, rigid transfer method is used to transfer films from an SrTiO 3 (STO) growth substrate onto various new substrates, including those that will typically pose significant problems for epitaxy. An epitaxial multiferroic Bi 3 Fe 2 Mn 2 O x (BFMO) layered supercell (LSC) material is selected as the thin film for this demonstration. The results of surface and structure studies show an order of magnitude increase in the continuous area of transferred films when compared to previous transfer methods. The magnetic properties of the BFMO LSC films are shown to be enhanced by the release of strain in this method, and ferromagnetic resonance is found with an exceptionally low Gilbert damping coefficient. The large-area transfer of this highly strained complex oxide BFMO thin film presents enormous potential for the integration of many other multifunctional oxides onto new substrates for future magnetic sensors and memory devices.

bismuth oxides↗
DOE OSTI2026

Discrimination of Hexane Isomers by Temperature Swing Adsorption in a Rigid Aluminum Metal–Organic Framework

The efficient separation of alkane isomers with similar physicochemical properties remains a persistent challenge for the petrochemical industry. Adsorptive separation using metal− organic frameworks (MOFs) offers an energy-efficient alternative to conventional distillation. Herein, we report temperature swing discrimination of hexane isomers with different degrees of branching using MIL-120, a rigid aluminum pyromellitate-based MOF. MIL-120 features uniform one-dimensional channels with an aperture of ∼5.5 Å. At 30 °C, it selectively adsorbs linear and monobranched hexanes while excluding the dibranched isomer. Upon heating to 120 °C, both mono- and dibranched isomers are completely excluded, whereas linear hexane remains strongly adsorbed. Breakthrough experiments validate the temperature swing separation performance. Adsorption heat analysis combined with ab initio calculations provides a quantitative measure of distinct differences in adsorption enthalpies, binding energies, and diffusion barriers responsible for the observed separation efficiency, highlighting the potential of this MOF for efficient separation of alkane isomers via temperature swing adsorption.

Adsorption↗
DOE OSTI2025

Rigid cationic ligands enable high-efficiency NIR-II photoluminescence in copper( i ) iodide hybrid semiconductors

Near-infrared (NIR) luminescent materials are pivotal for advanced optoelectronic and biomedical applications, yet attaining efficient emission in the NIR-II region (950-1400 nm) remains challenging. Here, we introduce a ligand cationization strategy for designing copper(i) iodide-organic hybrid materials that emit in the NIR-II region (920-1120 nm) with PLQYs up to 8.58%. By incorporating rigid cationic ligands with CuI modules, we synergistically achieve bandgap narrowing (to 1.51 eV) and structural rigidification via ionic-dative bonding, effectively suppressing non-radiative decay while extending emission beyond 1100 nm. Coupled with solution processability-enabled by the successful synthesis of nanometer-sized nanoparticles in various shapes-and excellent thermal stability (≥210 °C), this work establishes ligand cationization as a universal approach for designing efficient NIR-II emitters.

Chen, Jingwen↗