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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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Enhanced electric-field-induced strains in (K,Na)NbO3 piezoelectrics from heterogeneous structures
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Molecular heterogeneity in pyrogenic dissolved organic matter from a thermal series of oak and grass chars
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Comparison of Darcy's law and invasion percolation simulations with buoyancy-driven CO2-brine multiphase flow in a heterogeneous sandstone core
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Conservation of migration area by transport cross sections using Cumulative Migration Method in deterministic heterogeneous reactor transport analysis
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The relationship between fault zone structure and frictional heterogeneity, insight from faults in the High Zagros
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Heterogeneous Nucleation and Growth of Nanoparticles at Environmental Interfaces
Abstract not provided
Light-Driven Heterogeneous Reduction of Carbon Dioxide: Photocatalysts and Photoelectrodes
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Heterogeneous nature of relaxation dynamics of room-temperature ionic liquids (EMIm) 2 [Co(NCS) 4 ] and (BMIm) 2 [Co(NCS) 4 ]
Dynamic crossover above T g has been recognized as a characteristic feature of molecular dynamics of liquids approaching glass transition. Experimentally, it is manifested as a change in Vogel Fulcher Tammann dependence or a breakdown of the Stokes Einstein and related relations. In this paper, we report the exception from this rather general pattern of behavior. By means of dielectric, ultrasonic, rheological, and calorimetric methods, dynamics of two good ionic conductors (BMIm) 2 [Co(NCS) 4 ] and (EMIm) 2 [Co(NCS) 4 ] of less common stoichiometry (2:1) was studied in a very broad temperature range. However, none of the mentioned dynamic changes was observed in the entire studied temperature range. On the contrary, the single VFT and the same fractional Walden coefficient were found for conductivity and viscosity changes over 12 decades. Furthermore, ultrasonic studies revealed that the data at temperatures which cover the normal liquid region cannot be fitted by a single exponential decay, and the Cole Cole function should be used instead.
Nanoscale Confinement of All-Optical Magnetic Switching in TbFeCo - Competition with Nanoscale Heterogeneity
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2D Conductive Iron-Quinoid Magnets Ordering up to T c = 105 K via Heterogenous Redox Chemistry
Abstract not provided
Condensed-phase low temperature heterogeneous hydrogenation of CO 2 to methanol
A low-temperature CH 3 OH synthesis was achieved at 120–170 °C using tertiary amine and alcohol in the presence of a Cu/ZnO/Al 2 O 3 catalyst by CO 2 hydrogenation.
Nano-QSAR modeling for ecosafe design of heterogeneous TiO 2 -based nano-photocatalysts
The human health and environmental risk assessment of engineered nanomaterials (NPs) is nowadays of high interest.
Organic-Mineral Interfacial Chemistry Drives Heterogeneous Nucleation of Sr-Rich (Bax, Sr1-x)SO4 from Undersaturated Solution
Sr-bearing marine barite [(Bax, Sr1-x)SO4] cycling has been widely used to reconstruct geochemical evolutions of paleoenvironments. However, an understanding of barite precipitation in the ocean, which is globally undersaturated with respect to barite, is missing. Moreover, the reason for the occurrence of higher Sr content in marine barites than expected for classical crystal growth processes remains unknown. Field data analyses suggested that organic molecules may regulate the formation and composition of marine barites; however, the specific organic–mineral interactions are unclear. Using in situ grazing incidence small-angle X-ray scattering (GISAXS), size and total volume evolutions of barite precipitates on organic films were characterized. The results show that barite forms on organic films from undersaturated solutions. Moreover, from a single supersaturated solution with respect to barite, Sr-rich barite nanoparticles formed on organics, while micrometer-size Sr-poor barites formed in bulk solutions. Ion adsorption experiments showed that organic films can enrich cation concentrations in the adjacent solution, thus increasing the local supersaturation and promoting barite nucleation on organic films, even when the bulk solution was undersaturated. The Sr enrichment in barites formed on organic films was found to be controlled by solid-solution nucleation rates; instead, the Sr-poor barite formation in bulk solution was found to be controlled by solid-solution growth rates. This study provides a mechanistic explanation for Sr-rich marine barite formation and offers insights for understanding and controlling the compositions of solid solutions by separately tuning their nucleation and growth rates via the unique chemistry of solution–organic interfaces.
In situ characterization of tensile behavior of laser rapid solidified Al–Si heterogeneous microstructures
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