Jack L. Lambert

Phenoxazine as a solid monitoring reagent for ozone

Phenoxazine exhibits selectivity for reaction with ozone in concentrations normally found in air to produce a brown color of exceptional stability. It reacts with nitrogen dioxide to form a red-orange product that is visually distinct from the dull brown produced by the reagent with ozone. The solid reagent on cellulose paper is intended for visual comparison to prepared color standards in passive monitoring or warning devices.

Test Strip For The Rapid Identification of Sulfite on Foods

Abstract A rapid, sensitive, test strip has been developed for those people allergic to sulfite on foods. The strip is composed of a mixture of orange I, brilliant green, and sodium hydrogen carbonate deposited on 80-120 mesh alumina. Within 15 seconds the black strip turns red in the presence of as little as 0.5 ug of sulfite or green in the absence of sulfite.

Asensitive, Selective, and Rapid Colorimetric Method to Determine Cyanide Contamination in Containers, Capsules, and Liquids

Abstract A new formulation of the Konig colorimetric method for cyanide is selective, has increased stability, and is sensitive to a few ppb. The formulation can be placed as a strip on the safety seals of bottles to indicate tampering, placed in a syringe and used to sample head space gas in commercial products or liquids to test for tampering, or placed in the desiccant container in bottles of capsules or tablets. Reaction with head space gas requires just a few seconds, and less than an hour is required if the cyanide must first permeate through capsules. Liquids also can be either drawn directly into the syringe, or the cyanide evolved by adding an Alka-seltzer tablet to purge the gas. Reactions are immediate. Hydrogen sulfide and ammonia which interfere with several other cyanide tests, do not interfere with this formulation. A mixture of N-chlorosuccinimide and succinimide oxidizes CN- to CN+. The cyanogen ion selectively reacts with 4-phenylpyridine to form a dialdehyde, which is then coupled with ...

Colorimetric determination of fluoride ion with a solid analytical reagent

Abstract A colorimetric procedure is proposed for the estimation of fluoride ions in μg range in aqueous samples. The method involves the use of a solid analytical reagent and exhibits an operational simplicity. The detection limit of 1 ppm in an aqueous sample is conveniently achieved in the direct application. The interfering ions are initially removed in an ion exchange step, which also serves as a concentration step for fluoride if present in low concentration.

A New Colorimetric Reagent for Carbon Monoxide

Abstract A new colorimetric reagent for carbon monoxide is described. The reaction sequence apparently involves reduction by carbon monoxide of [PdCl4]2-, which then reduces [FeIII EDTA]− to [FeIIEDTA]2-. The latter undergoes ligand exchange with 2,2′-dipyridyl or 1,10-phenanthroline to form the more stable colored [FeL3]2+, which is measured spectrophotometrically. Sodium molybdate enhances the overall reaction. The color intensity produced is non-linear but reproducible. The method is unique in that a soluble colored compound is produced rather than a metal sol.

Sensitive Solid Reagent For Formaldehyde, And A New Formaldehyde Generator

Abstract A solid reagent of Purpald®-acetone aminal on sodium or potassium bicarbonate responds to formaldehyde in the sub-ppm concentration range. A purple color (λ=560 nm) is developed proportional to concentration of formaldehyde and time of exposure after wetting with a 90% acetone-10% water solution. The reagent should be of value as a semi-quantitative warning device for the presence of formaldehyde. A device is described which generates formaldehyde in air in the sub-ppm concentration range at room temperature with desired relative humidity. This generator could be used in the same manner to generate low concentrations of other substances of low volatility.

Tin(II)-diphenylcarbazide Complex as a Solid Reagent in Monitoring Devices for Atmospheric Oxidants

Abstract The tin(II)-diphenylcarbazide complex, [Sn(C13H14N4O)2]Cl2 or [Sn(C13H14N4O)2Cl2], applied as an acetone solution to cellulose (filter paper) or starch and dried, is oxidized to the red-violet diphenylcarbazone by ozone and nitrogen dioxide - the principal atmospheric oxidants - at concentrations below 1 ppm. The supported reagent is stable indefinitely when kept in a sealed bottle.

Palladium(II)-acetamide complex as a solid monitoring reagent for carbon monoxide.

A study of solid salts containing cationic complexes of palladium(II) with neutral, weakly complexing ligands resulted in the discovery of the palladium(II)-acetamide-tetrafluoroborate reagent, in which acetamide is present in 20-fold molar excess. It was found that a successful reagent of this type must have a ligand that complexes palladium(II) weakly, but more strongly than does water, with water available for subsequent reaction. Carbon monoxide appears to coordinate with the palladium(II)-acetamide complex, which then reacts with water to form, simultaneously, palladium(O) metal that is black, carbon dioxide, and hydrogen ion. The reagent is described as a visual warning device for the present of carbon monoxide. 5 figs., 1 tab.

Introductory Remarks: Some Partially Solved Problems in Anion Analysis

While instrumental methods of analysis occupy our attention to an increasing degree these days, we find the traditional wet chemical methods solidly entrenched in the area of water analysis.

The hydrates of sodium hyponitrite

Abstract Novel 2- and 3 1 2 - hydrates of sodium hyponitrite are reported for the first time. Karl Fischer titrations and X-ray crystallographic analyses were used in the determination of these salts. Reexamination by Karl Fischer titration of earlier preparations of 5- and 8-hydrates of sodium hyponitrite show a smaller number of lattice waters than first reported by Partington and Shah.