Author
Lester C. Howick
Bio: Lester C. Howick is an academic researcher from University of Iowa. The author has contributed to research in topics: Solubility & Thermal decomposition. The author has an hindex of 2, co-authored 2 publications receiving 110 citations.
Topics: Solubility, Thermal decomposition, Diphenylcarbazide, Chromium
Papers
More filters
113 citations
12 citations
Cited by
More filters
TL;DR: In this article, an electrospun polyacrylonitrile (PAN) nanofibrous scaffold was grafted with cysteine to increase the adsorption capability for chromium (VI) and lead (II) using titration, FT-IR, and energy dispersive spectroscopy (EDS) techniques.
203 citations
TL;DR: A new sensitive, colorimetric method based on the direct measurement of light-absorption by an ion-exchange resin phase, which has sorbed the sample complex species, has been developed and determinations ofchromium(VI) with diphenylearbazide, iron(II) with 1,10-phenanthroline, copper with Zincon and cobalt with thiocyanate have more than ten times the sensitivity obtainable with conventional solution colorimetry.
154 citations
TL;DR: An attempt to use Al2O3, as non-semiconductor component to improve the photocatalytic activity of V2O5 was investigated in this paper, where the composite photocatalyst was synthesized by coprecipitation-calcination process, and then characterized by X-ray powder diffraction (XRD), UV-vis diffuse reflectance spectroscopy (DRS), photoluminescence (PL) emission spectra, transmission electron microscopy (TEM), and Fourier transform infrared (FT-IR) spectra.
94 citations
TL;DR: In this paper, the absorption of Cr(VI) in an aqueous solution is conducted by direct UV-visible spectrophotometry based on the yellow coloring of the chromate ion.
84 citations
TL;DR: The composition of PIS was optimized to obtain maximum uptake of Cr(VI) without sacrificing uniformity in terms of thickness and distribution of ion-exchange sites, stability, and time required for quantitative sorption of Cr (VI) from aqueous samples.
Abstract: A method for sorption preconcentration of Cr(VI) from aqueous samples was developed using a polymer inclusion sorbent (PIS). The PIS used in this method was prepared by physical inclusion of Aliquat-336 in the matrix formed by cellulose triacetate and 2-nitrophenyl octyl ether. This sorbent was found to be stable, cost-effective, efficient for preconcentration of Cr(VI) present in the aqueous samples, and amenable to direct quantitative analysis of Cr(VI) held in it by neutron activation analysis and spectrophotometry. The quantifying of Cr(VI) in PIS by spectrophotometry was carried out by developing color directly on the PIS after reacting it with 1,5-diphenylcarbazide. The distinct color developed on the PIS even at very low concentrations of Cr(VI) suggests its possible use for field determination of Cr(VI). The composition of PIS was optimized to obtain maximum uptake of Cr(VI) without sacrificing uniformity in terms of thickness and distribution of ion-exchange sites, stability, and time required fo...
70 citations