Ion-exclusion chromatography was examined for the simultaneous spectrophotometric determinations of orthophosphate and silicate ions in river water using an ascorbate solution as both an eluent and a reducing agent, followed by postcolumn derivatization using molybdate. The detector responses for both ions increased with increased ascorbic acid concentration in the eluent, but peak tailing was ...

In this study, the effect of molybdate on the electrochemical behavior and semi-conductive properties of duplex stainless steel 2205 passive film at NaCl solutions was investigated. Cyclic potentiodynamic polarization, impedance spectroscopy, mott-schottky plots and scanning electron microscopy (SEM) were used to study the passive behavior. Polarization curves showed that the corrosion current ...

The relationship of the XY model, which arises from a C4 " image, to the phase transition in the rare-earth molybdate Tb2(Mo04)3 (TMO) is discussed. We point out that this model does not describe the TMO transition, but that a Landau expansion arising from a C4 image is the appropriate free-energy model. Recently, Galam' considered phase transitions occurring in the XY model with cubic anisotro...

Estimation of inorganic phosphate in serum based on the formation of "molybdenum blue" may be simplified by eliminating the reduction stage. The yellow complex formed by the reaction of phosphate with molybdate in an acid medium is measured at 390 nm. The yellow complex behaves in accordance with Beer's law over a wide concentration range (to at least 80 mg of P per liter in the initial sample)...

We adapted the pyrogallol red-molybdate method for total urinary protein to the Cobas Bio centrifugal analyzer. The method is simple, rapid, sensitive, and inexpensive. Addition of 25 mg of sodium dodecyl sulfate per liter to the reagent modifies protein reactivities so that the chromogenicity of human gamma globulins is the same as that of albumin. Results by this method and a comparison metho...

A highly sensitive fourth derivative spectrophotometric method is presented for the residue analysis of ethylenebis dithiocarbamate fungicide Maneb. The fungicide maneb forms a blue complex with sodium molybdate on heating which is studied spectrophotometrically. The method has been successfully applied to maneb determination in wheat grains and soft drinks with high recoveries. The analytical ...

Mercury methylation and demethylation rates were measured in periphyton biofilms growing on submerged plants from a shallow fluvial lake located along the St. Lawrence River (Quebec, Canada). Incubations were performed in situ within macrophytes beds using low-level spikes of (199)HgO and Me(200)Hg stable isotopes as tracers. To determine which microbial guilds are playing a role in these proce...