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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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Structure directing agents were designed in this work to aid in the synthesis of four zeolites predicted to efficiently separate ethane and ethylene.
Tailorable multicomponent MOFs and MOF membranes for efficient H 2 /CO 2 separation.
With multi-hydrophilic functional networks, asymmetric PAN nanofiber membranes with finely tailored pore structures and hydrophilicity are constructed and show high permeance 22 000 L m -2 h -1 bar -1 , separation efficiency 99.2% and flux recovery rate 98%.
Diblock copolypeptoids have the capacity to phase separate, crystallize, and self-assemble into a variety of nanostructures, which have shown great potential in a variety of biological applications.
Two-step solar thermochemical cycles based on reversible reactions of SrFeO 3–δ and (Ba,La) 0.15 Sr 0.85 FeO 3–δ perovskites were considered for air separation. The cycle steps encompass (1) the thermal reduction of SrFeO 3–δ or (Ba,La) 0.15 Sr 0.85 FeO 3–δ perovskites driven by concentrated solar irradiation and (2) oxidation in air to remove O 2 and produce N 2 . Rate limiting mechanisms were examined for both reactions using a combination of isothermal and non-isothermal thermogravimetry for temperature-swings between 673 and 1373 K, heating rates of 10, 20, and 50 K min –1 , and O 2 pressure-swings between 20% O 2 /Ar and 100% Ar at atmospheric pressure. Evolved O 2 and associated lag due to transport behavior were measured with gas chromatography and used with measured sample temperatures to predict equilibrium compositions from a compound energy formalism thermodynamic model. Measured and predicted chemical equilibrium changes in deviation from stoichiometry were compared. Rapid chemical kinetics were observed as the samples equilibrated rapidly for all conditions, indicative that heat and mass transfer were the rate limiting mechanisms. Furthermore, the effects of bulk diffusion (or gas diffusion through the bed or pellet) were examined using pelletized and loose powdered samples and determined to have no discernable impact.
A self-assembling, biporous covalent organic framework has been constructed from a single monomer and applied to gas separations. Coordination of transition metals in the monomer leads to highly ordered arrangements of metals in the 2D-materials.
3,4,3-LI(1,2-HOPO) can be used as a HPLC chelating agent, promoting lanthanide and trivalent actinide separation without column modifications.
3D printed membrane device, supported ionic liquid membrane, hydrogel-coated hydrophilic/oleophobic membrane, multi-component multi-phase separation.
Water electrolysis at a bipolar electrode in the absence of buffer forms electric field gradients in a fundamentally new way. These electric field gradients are useful for continuously separating microplastics from water.
Integration of a sodium anode chemistry and a TEMPO cathode chemistry enables the advancement of a high voltage nonaqueous hybrid flow battery (HFB). A single-ion solid-electrolyte separator ensures a crossover-free operation of the HFB.
The brightness of an emitter can be enhanced by metal-enhanced fluorescence, wherein the excitonic dipole couples with the electromagnetic field of the surface plasmon. In this report, we experimentally map the landscape of photoluminescence enhancement (EF exp ) of emitters in a plasmonic field as a function of the emitter–emitter separation, s, and the emitter–plasmon distance, t. We use Au nanoparticles overcoated with inert spacers as plasmonic systems and CdSe/ZnS quantum dots (QDs) as an emitter bearing opposite surface charges. The t and s are varied by changing the spacer thickness and number density of QDs on the plasmonic surface, respectively. The electrostatic binding of emitters on the plasmonic surface and their number density are established by following the variation of zeta-potential. EF exp is high, when t is short and s is large; nevertheless, it decreases when the emitter–emitter interaction dominates due to plasmon assisted nonradiative processes. In the absence of a plasmonic field, the enhancement observed is attributed to environmental effects and is independent of s, confirming the role of the electric field. Indeed, the distance dependence of EF exp closely follows the decay of the plasmonic field upon dilution of the emitter concentration on nanoparticles’ surface (s = 18 nm). The QD–plasmon system is visualized in the framework of the Thomson problem, and classical electrodynamics calculations give the trends in t and s dependence of the photoluminescence. Being the first report on the simultaneous dependence of t and s on plasmon-enhanced photoluminescence, the results presented herein will open newer opportunities in the design of hybrid systems with a high brightness.
Siloxane with low surface tension can regulate the intermolecular interactions, and optimize the phase separation morphology and molecule stacking, finally contributing to an excellent PCE of 16.4% with small energy loss for ASM-OSCs.
Food packaging often appears in the form of multilayer (ML) plastic films, which leverage the functional properties of different polymers to achieve specific food protection goals (e.g., oxygen, water, and temperature barriers). These properties are essential to enable long shelf lives, reduce refrigeration usage, mitigate food waste, and increase food accessibility. However, ML film production processes generate large amounts of plastic waste that cannot be mechanically recycled. Recently, we have proposed a process, called solvent-targeted recovery and precipitation (STRAP), that enables the separation and recycling of the constituent polymers of ML films. This technology uses a series of solvent washes that selectively dissolve and precipitate target polymers. Quantifying the environmental benefits of STRAP over virgin resin production is essential for the commercial deployment of this technology. Further, this work uses life cycle assessment (LCA) methods to evaluate these impacts in terms of carbon footprint, energy use, water use, and toxicity. We analyze three STRAP process variants that use antisolvent and temperature-driven precipitation to treat different ML films. Our analysis reveals that the STRAP-A and STRAP-B process variants can provide environmental benefits over virgin film production. Furthermore, it gives valuable insight into the critical components of ML films (specific polymers) and of the STRAP processes (equipment) that are responsible for the highest impacts. Ultimately, we believe that the proposed analysis framework can lead to the design of more environmentally-friendly ML films and recycling processes.
Hourglass-shaped or bimodally distributed microcavities enable both high gas permeabilities and selectivities for highly energy-efficient gas separations.
Pu is separated from excess U and isotopically assayed using our novel microfluidic platform designed to miniaturize traditional laboratory techniques into a field-deployable system for rapid nuclear forensics in post-detonation nuclear scenarios.
N-oxide ligands, combined with pyridinic N groups, are predicted to offer attractive La( iii )/Ln( iii ) selectivities for rare-earth separations.
Morphological optimization has proved to be one crucial factor contributing to the 19% efficiency of Y6-based organic solar cells (OSCs). Although the relationship between component miscibility and film morphology has been established, it has not been clarified how the film formation processes proceed, especially for methods compatible with large-area fabrication, i.e. slot-die coating, which restricts the further optimization of the morphology. Herein, we comprehensively investigate the effect of miscibility and the film-formation kinetic process on film morphology during processing with different solvents. A highest power conversion efficiency (PCE) of 17.38% can be obtained in a D18:Y6 device processed with slot-die coating in an open-air environment. However, due to their relatively poor miscibility, incorporating a trace amount of chlorobenzene (CB) into CF can sufficiently promote Y6 aggregation, leading to increased phase separation and thus the average PCE drops to 15.16%. In contrast, a PM6:Y6 blend shows insensitive changes in the kinetic process as well as the final morphology, and thus in the comparable PCEs when cast with different solvents, which is ascribed to their relatively good miscibility. As a result, this work provides scientific guidelines for device optimization by combining the intermediate gap from miscibility to kinetic process and their impact on final morphology.
Formation of highly reducible ionic liquid lead complexes in dilute aqueous solutions opens up new opportunities to employ green ionic liquids to separate heavy toxic metals efficiently.