A spectrophotometric method for the determination of borohydride is described. It involves the reduction of NAD’ to a number of isomeric forms of NADH by borohydride. In the standard assay procedure herewith presented, there is a direct proportionality between the absorption at 340 nm and the amount of borohydride in solution over the range IO-100 nmoles, with an effective “molar extinction coe...

the difficult to handle and store zinc borohydride, zn(bh4)2, is stabilized by supporting it on polyvinylpyridine. this new mild, efficient, selective, and regenerable polymer supported borohydride reducing agent reduces a variety organic compounds such as, aldehydes, a-b-unsaturated carbonyl compounds, acid chlorides, epoxides, disulfides, as well as reductive acetylation of carbonyl compounds...

background: some particular areas contain natural radionuclide at levels much higher than those usually present in earth's crust. the radiological impact of the use of zirconium ore in zirconium industry is due to internal exposure of the lung by alpha particles and external exposure of the body by the gamma rays. the result of gamma spectrometry measurement of the concentrations of the na...

In the light of recent reports, based on radioactive labelling studies, that substantial amounts of N-linked oligosaccharides are released from protein under the mild-alkaline borohydride degradation conditions that are usually used to release O-linked oligosaccharides, we have investigated by chemical methods the effects of alkali alone and alkaline borohydride on the carbohydrate and peptide ...

The microstructure evolution of Zr-1.1Nb-1.51Fe-0.26Cu-0.72Ni zirconium alloy, irradiated by 800 keV Kr2+ ions at 585 K using the IVEM-Tandem Facility at Argonne National Laboratory, was observed by in situ transmission electron microscopy. A number of β-Nb precipitates with a body-centered cubic (BCC) structure were distributed in the as-received zirconium alloy with micrometer-size grains. Kr...

The separation of hafnium from zirconium using tributyl phosphate offers interesting alternatives to present methods for making reactor-grade zirconium. Feed solution for the extraction step can be prepared from the reaction product of caustic and zircon sand. The purified zirconium can be converted into a variety of compounds, depending on the process chosen for reduction to the metal. It may ...

Titanium and zirconium were immersed in Hanks’ solution with and without calcium and phosphate ions, and the surfaces were characterized with X-ray photoelectron spectroscopy (XPS) to determine the mechanism of calcium phosphate formation on titanium in simulated body fluids and in a living body. In addition, they were cathodically polarized in the above solutions. As a result, neither calcium ...

Many materials that are usually found in the earth's crust contain small but measurable amount of naturally occurring radioactivity (NORM). Some particular ores contain natural radionuclide at levels much higher those usually present in earth's crust; and are also subject to radioisotope enrichment, during technological process, known as technologically enhanced natural radioactivity (TENORM). ...