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Jang, Harry

Publications and source records attributed to Jang, Harry.

9 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2024

Revealing uranium tetrafluoride microrods

Uranium tetrafluoride microrods were prepared by chemical transformation from the reaction of UO 2 microrods with HF(g).

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2022

Thermal behavior of ammonium octafluorodirhenate(III)

The thermal behavior of (NH 4 ) 2 [Re 2 F 8 ]·2H 2 O salt was studied in the temperature range 150–700 °C under flowing nitrogen gas. The decomposition products were studied by powder X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Results are consistent with the formation of (NH 4 ) 2 [Re 2 F 8 ] salt at 150 °C, amorphous rhenium metal at 300 and 400 °C, and crystalline rhenium metal at 500 and 700 °C. A mechanism of formation of rhenium metal from (NH 4 ) 2 [Re 2 F 8 ]·2H 2 O was proposed. Here, the effect of crystallite size and lattice strain was evaluated at 500 and 700 °C from powder XRD peak broadenings using both Williamson–Hall and the modified Scherrer methods.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2022

Synthetic diversity in the preparation of metallic uranium

Uranium metal is associated with several aspects of nuclear technology; it is used as fuel for research and power reactors, targets for medical isotope productions, explosive for nuclear weapons and precursors in synthetic chemistry. The study of uranium metal at the laboratory scale presents the opportunity to evaluate metallic nuclear fuels, develop new methods for metallic spent fuel reprocessing and advance the science relevant to nuclear forensics and medical isotope production. Since its first isolation in 1841, from the reaction of uranium chloride and potassium metal, uranium metal has been prepared by solid-state reactions and in solution by electrochemical, chemical and radiochemical methods. The present review summarizes the methods outlined above and describes the chemistry associated with each preparation.

36 MATERIALS SCIENCE↗
DOE OSTI2019

Preparation and characterization of benzotriazolium perrhenate

The title compound, [C 6 H 6 N 3 ][ReO 4 ], crystallizes in the monoclinic space group P2 1 /c (a = 12.854(2) Å; b = 4.9121(8) Å; c = 14.819(2) Å). The solid-state structure of the compound is stabilized by a series of hydrogen bonds. The solubility of [C 6 H 6 N 3 ][ReO 4 ] was measured in H 2 O, CH 3 OH (MeOH), and HCl (0.5 M and 6 M). Nuclear magnetic resonance measurements ( 1 H NMR and 13 C NMR) were performed, and results were consistent with the presence of the organic cation. The UV–visible spectrum shows a solvent dependency which DFT simulations indicate arise from which benzotriazole (BTA) species are present in solution (i. e., [C 6 H 4 N 3 ] - in H 2 O, C 6 H 5 N 3 in MeOH and [C 6 H 6 N 3 ] + in 5 M HCl).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗