Uronate isomerase, a member of the amidohydrolase superfamily, catalyzes the isomerization of D-glucuronate and D-fructuronate. During the interconversion of substrate and product the hydrogen at C2 of D-glucuronate is transferred to the pro-R position at C1 of the product, D-fructuronate. The exchange of the transferred hydrogen with solvent deuterium occurs at a rate that is 4 orders of magni...

We report on the steady-state, picosecond and femtosecond time-resolved studies of a charge and proton transfer dye 6-amino-2-(2'-hydroxyphenyl)benzoxazole (6A-HBO) and its methylated derivative 6-amino-2-(2'-methoxyphenyl)benzoxazole (6A-MBO), in different solvents. With femtosecond resolution and comparison with the photobehaviour of 6A-MBO, we demonstrate for 6A-HBO in solution, the photopro...

This article is a longer and more complete version of a comment I posted on Nature journal’s website. Go to the article “Supernova 'kaleidoscope' seen for first time” by Maggie McKee (http://www.nature.com/news/supernova-kaleidoscope-seen-for-first-time1.17062) and scroll way down the page to read it. So the best abstract I can think of is to reproduce that comment here. Is gravitational lensin...

We re-evaluate the nuclear matrix element for the proton-proton reaction p + p → H + e + νe, which is important for stellar-evolution calculations referring to stars with masses < ∼ 1M⊙ and for the solar-neutrino problem. We selfconsistently determine the effect of vacuum polarization on the matrix element by first correcting the low-energy scattering data to account for vacuum polarization. We...

Environmental concerns about carbon emissions are motivating development of Proton-Exchange Membrane Fuel Cell (PEM-FC) technology for automotive propulsion. Catalyst Coated Membranes (CCM), which are the electrochemical „heart‟ of PEM-FC, consist of a proton-conductive polymer membrane embedded between two porous, electron conductive electrodes. The catalyst in the cathode consists of Pt nanop...

Ruthenium-103 is the parent isotope of 103mRh (t1/2 56.1 min), an isotope of interest for Auger electron therapy. During the proton irradiation of thorium targets, large amounts of 103Ru are generated through proton induced fission. The development of a two part chemical separation process to isolate 103Ru in high yield and purity from a proton irradiated thorium matrix on an analytical scale i...

In this paper, the surface stoichiometry, acid-base properties as well as the adsorption of xanthate at ZnS surfaces were studied by means of potentiometric titration, adsorption and solution speciation modeling. The surface proton binding site was determined by using Gran plot to evaluate the potentiometric titration data. Testing results implied that for stoichiometric surfaces of zinc sulfid...

Proton exchange membrane fuel cells have been receiving more and more attention these recent years. Maintaining a fuel cell system in correct operating conditions requires good controller. Based on the mathematical model of proton exchange membrane fuel cells described in this paper, the fuzzy logic controllers was designed for the proton exchange membrane fuel cell to make it possible to outpu...

Sulfonated polyether ether ketone (SPEEK) is categorized in a nonfluorinated aromatic hydrocarbon proton exchange membrane (PEM) group and considered as a suitable substitute for common per-fluorinated membranes, such as Nafion, due to wider operating temperature, less feed gas crossover, and lower cost. Since modeling results in a better understanding of a phenomenon, in this study a dynamic o...