Sorption of phosphine by cereal products

Abstract

Phosphine gas (PH3) was applied at concentrations of 0.15 to 0.60 mg. per liter to wheat, oats, barley, flax, and milled grain products in closed containers. No free PH3 remained in any of the substrates after accelerated aeration with nitrogen. Irreversible sorption, considered chemisorption by the author, was reproducibly obtained under the experimental conditions employed. The amount of PH3 chemisorbed was mainly affected by the type, moisture content, and physical form of the substrate, as well as by temperature and contact time. With milled wheat products, the uptake of PH3 by wheat gluten powder, middlings, bran, and shorts was greater than that by wheat starch, flour, and wheat germ. For four different concentrations used, the absolute amounts of PH3 sorbed were directly proportional to the amounts applied, as for first-order reactions. Presumptive evidence that PH3 binds with proteins and complexes with mineral components of the substrates is discussed.

A Variable Response Phosphine Sensing Matrix Based on Nanostructure Treated p and n-Type Porous Silicon Interfaces

“…This demonstrates the need to optimize the fractional nanostructured coating in these and other system. PH 3 represents a moderately strong base [1] whose behavior on an n-type surface, as it contributes electrons, should lead to a decrease in resistance with increased concentration [4], [26]. However, the responses observed for the interaction of PH 3 with an n-type interface are more complicated.…”

“…P HOSPHINE is an extremely toxic gas widely used in agriculture for fumigation [1]. It is the only widely used fumigant that kills insects rapidly without leaving residues on the product.…”

“…It is also an illicit product of methamphetamine (meth) labs [2]. There is a considerable need for locating the signatures of [1] illegal meth labs without the need for the illicit entering of the large number of small scale facilities increasing throughout the United States. The Occupational Safety and Health Administration (OSHA) sets an exposure limit of 0.3 parts per million (ppm) PH 3 for an 8 hour workshift, 40 hrs a week [3].…”

New Generation Devices for Gas (Liquid) Sensing

“…NH 3 , which plays an especially important role in urban environments [5,6], also is produced albeit at much lower levels, during an asthma attack. SO x and H 2 S [7][8][9] as well as NO x play an important role in automotive and industrial exhaust, acid rain, photochemical smog, and corrosion [3] and natural gas venting.. PH 3 is an extremely toxic gas used for fumigation in agriculture and is a byproduct in the production of methamphetamines [10,11]. Advances in gas sensor technology used to monitor these exemplary gases have been driven by sensitivity, selectivity, stability, response time, and durability.…”

Determination of Zinc Phosphide Residues in Corn ( Zea mays ) Grain, Fodder, and Forage

“…Previous methods quantified zinc phosphide residues in sugar cane (Hilton and Robinson 1972), range vegetation (Okuno et al 1975), sugar beets (University of California 1989), and potato tubers (University of Idaho 1995) by hydrolyzing zinc phosphide in an acid solution to produce phosphine gas, which was subsequently quantified by headspace sampling and gas chromatography-flame photometric detection. Unfortunately, phosphine gas is highly reactive and appears to react with plant constituents, resulting in limited and variable recoveries ranging from 33 · 84 percent (Hilton and Robinson 1972, Okuno et al 1975, University of California 1989, University of Idaho 1995, Berk 1968, Berk and Gunther 1979.…”