Ultra-thin films of solution-exfoliated hexagonal boron nitride by Langmuir deposition

Langmuir films of pure, solution-exfoliated hexagonal boron nitride, transferable to arbitrary substrates, are demonstrated as promising dielectric layers suitable for transparent and flexible optoelectronics.

The Specificity of Di-(2-ethylhexyl) Phosphoric Acid (HDEHP) Method for Yttrium-90 in Foods: Modification for Fresh Heavy Fallout Conditions

Di-2-ethylhexyl phosphoric acid reagent from two commercial sources was investigated for a study of specificity of determining yttrium-90. Titration curves indicate no significant quantity of monoalkyl phosphoric acid ester, the only limiting impurity expected. The following radionuclides in pure solution were examined for removal of activity from yttrium-90: Ru-106/Rh-196, Zr-95/Nh-95, Ce-144/Pr-144, Ca-45, Mo-99, Zn-65, Cr-51, Fe-59, Ba-140/La-140, Cs-137, Nd-147/Pr-147. Both sources of reagent were highly effective in removal of activity of the introduced radionuclide. The removal of activity to within 0.1% of that initially introduced was demonstrated in all cases except the Ce-144/Pr-144 pair; in this case activity was reduced to within the 0.1% range by substituting a 0.1M HC1 wash for the normal wash at pH 1.4. Data arc included for the precision of the HDEHP method relative to picocuries of food ash analyzed and the standard deviation of the analysis.