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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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Crystal Growth of Alkali Uranyl Borates from Molten Salt Fluxes: Characterization and Ion Exchange Behavior of A 2 (UO 2 )B 2 O 5 (A = Cs, Rb, K)
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Flux Synthesis of Alkaline-Earth Lanthanide Borates as Potential Nuclear Waste Forms
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Mechanisms of Photoluminescence in Copper-Containing Fluoride Borate Crystals
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Temperature-Driven Structural Transitions in Molten Sodium Borates Na2O-B2O3: X-ray Diffraction, Thermodynamic Modeling, and Implications for Topological Constraint Theory
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Effect of Lithium Borate Additives on Cathode Film Formation in LiNi 0.5 Mn 1.5 O 4 /Li Cells
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CO (2) Electroreduction on Borated Copper Surfaces: Boron Active Sites, Not Copper
Boron-doped copper has recently emerged as an active and stable catalyst for the electrochemical reduction of CO 2 to value-added C 2 products. Here, in this work, we develop a realistic model of CO electroreduction on surface borides of copper under operational conditions, taking into account the effects of electrode potential, electrolyte environment, and pH. We study the possible reconstruction of the electrocatalyst surface using grand canonical DFT and global optimization to obtain a potential-dependent grand canonical ensemble description of metastable, hydrogen-covered catalyst surfaces. Two key surface configurations, low H coverage (LC, −0.6 V SHE ) and high H coverage (HC, −0.8 V SHE ), dominate this ensemble, with the former being kinetically persistent and C 2 selective under strongly reducing conditions. Nonmetallic boron sites on the surface copper boride are found to bind CO more strongly than copper sites, and mechanistic investigation of CO electroreduction pathways presents a surprisingly unconventional case of boron-centered reactivity in contrast to typical copper-centered reactivity. Neighboring boron sites present along boron chains on the surface copper boride are found to facilitate C−C coupling, thereby driving the high C 2 selectivity of this electrocatalyst.
Stabilizing Superionic-Conducting Structures via Mixed-Anion Solid Solutions of Monocarba- closo -borate Salts
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Reversible Calcium Plating and Stripping at Room Temperature Using a Borate Salt
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Hydrogenation properties of lithium and sodium hydride – closo -borate, [B 10 H 10 ] 2− and [B 12 H 12 ] 2− , composites
The hydrogen absorption properties of metal closo -borate/metal hydride composites are studied under high hydrogen pressures.
Organophosphorus decorated lithium borate and phosphate salts with extended π-conjugated backbone
Several new bifunctional salts, Li[B(DPN)2] , Li[B(DPN)(ox)] and Li[P(DPN)3] , have been prepared from the phosphorus( v )-containing chelating ligand 2,3-dihydroxynaphthalene-1,4-(tetraethyl)bis(phosphonate) ( H2-DPN ).
Glass composition and excitation wavelength dependence of the luminescence of Eu{sup 3+} doped lead borate glass
This work explores the relationship between the bandwidth of luminescence spectral features and their relative intensities, using glasses doped with europium, Eu{sup 3+}, over a wide composition range. Glasses of composition (B{sub 2}O{sub 3}){sub 70}(PbO){sub 29}(0.5Eu{sub 2}O{sub 3}){sub 1} and (B{sub 2}O{sub 3}){sub z}(PbO){sub 99.6-z}(0.5Eu{sub 2}O{sub 3}){sub 0.4}, (z = 20, 30, 40, 60, 70), were prepared by the melting-quenching technique. Variable-wavelength measurements by the prism-coupling method enabled interpolation of refractive index at selected wavelengths. Diffuse reflectance spectra confirmed the incorporation of Eu{sup 3+} into the glass, and scanning electron microscopy displayed that this was in a homogeneous manner. Vibrational spectra showed a change in boron coordination from BO{sub 3} to BO{sub 4} units with increase of PbO content in the glass. Multi-wavelength excited luminescence spectra were recorded for the glasses at temperatures down to 10 K and qualitative interpretations of spectral differences with change of B{sub 2}O{sub 3} content are given. The quantitative analysis of {sup 5}D{sub 0} luminescence intensity-bandwidth relations showed that although samples with higher boron content closely exhibit a simple proportional relationship with band intensity ratios, as expected from theory, the expression needs to be slightly modified for those with low boron content. The Judd-Ofelt intensity analysis of the {sup 5}D{sub 0} emission spectra under laser excitations at low temperature gives {Omega}{sub 2} values within the range from (3.9-6.5) x 10{sup -20} cm{sup 2}, and {Omega}{sub 4} in the range from (4.1-7.0) x 10{sup -20} cm{sup 2}, for different values of z. However, no clear monotonic relation was found between the parameter values and composition. The Judd-Ofelt parameters are compared with those from other systems doped with Eu{sup 3+} and are found to lie in the normal ranges for Eu{sup 3+}-doped glasses. The comparison of parameter values derived from the 10 K spectra with those from room temperature spectra for our glasses, which are fairly constant for different compositions, shows that site selection occurs at low temperature.
Effect of alkali addition on DC conductivity and thermal properties of vanadium-bismo-borate glasses
The DC Conductivity and Differential Thermal Analysis of glasses with composition (30−x)Li{sub 2}O⋅xV{sub 2}O{sub 5}⋅20Bi{sub 2}O{sub 3}⋅50B{sub 2}O{sub 3}(x=15, 10, 5) has been carried out in order to study the effect of replacing the Transition Metal Oxide (TMO) with alkali oxide. A significant increase in the DC conductivity has been observed with increase in alkali content. Again the thermal measurements have shown the decrease in both glass transition temperature (T{sub g}) and crystallization temperature (T{sub x}). The Glass Stability (GS) and Glass Forming Ability (GFA) have also been calculated and these also were found to decrease with increase in alkali oxide content at the cost of TMO.