nmr study of constituent unit distribution in cellulose acetates

distribution of repeat units in cellulose acetates was followed by **1 h nmr. quantitative data on the distribution of substituents in the polymer, in particular on localization of acetate groups on carbon atoms c-2, c-3, c-6 were obtained from spectra of acetates with euterated hydroxyl groups. cellulose acetate, $alpha$ -cellobiose octa..

anaerobic microbial dechlorination: an approach to on-site treatment of toxaphene-contaminated soil

enhanced microbial degradation of toxaphene by natural microorganisms occurred in soil and sediment amended with organic matter kept under anaerobic (flooded) conditions. laboratory experiments yielded a dissipation half-life of approximately 3 and 1 week for soil and sediment, respectively, containing 10 ppm of technical toxaphene and a ..

reuse of domestic wastewater for irrigation in arid zones: a case study

the domestic sewage of the city of beer-sheva, israel, which is located in an arid region, is treated in a series of facultative ponds. the treated effluent is stored temporarily in an open surface earthen reservoir (about 0. 5 $multiplied by$ 10**6 m**3 in volume) and then used for irrigation. the effluent is applied via sprinkler and tr..

response of cotton to treated domestic wastewater applied through trickle irrigation

row spacing was either conventional, i. e. single rows apart, or in twin rows. 0. 96 m and 1. 92 m apart (a twin row consists of a pair 0. 35 m apart). some treatments received the commercial rates of effluent application (around 5,500 m**3/ha) as commonly practiced in the area, others received a reduced amount, 80 of the commercial rate...

study of the sulfuric acid-acetic anhydride complex in dioxane

a new process has been developed for production, by direct acetylation, of soluble cellulose acetates having degrees of substitution of 0. 9-2. 0 in dioxane with the use of large amounts of sulfuric acid. it was shown earlier that sulfuric acid, which is widely used as an acetylation catalyst, forms an equimolecular complex with acetic an..

binder for making foundry cores and molds finished by baking

the possibility of using the oil-grease residue from black cotton oil, lacquer grade gasoline and a siccative as a binder mixture has been investigated with a view to enhancing the strength of baked cores and molds, shortening the baking period of the molding sand, replacing raw materials in short supply, and reducing atmospheric pollutio..

soil and sun angle interactions on partial canopy spectra

the spectral behavior of an incomplete cotton canopy was analyzed in relation to solar zenith angle and soil background variations. soil and vegetation spectral contributions towards canopy response were separated using a first-order interactive model and consequently used to compare the relative sensitivity of canopy spectra to soil back..

laundering variables in removing carbaryl and atrazine residues from contaminated fabrics

during mixing and application of pesticides, the clothing worn by agricultural or urban pesticide applicators is subject to contamination. completeness of pesticide removal in laundering is essential if the garment is to be used again. this study examines the efficacy of laundering variables such as detergent type, wash water temperature ..

occurrence of dde in dairy feeds in the arizona milk shed

the state of arizona imposed a moratorium on the use of toxaphene for agriculture in 1979. since that time, dichloro-diphenyl-dichloroethylene (dde) has been the principle organochlorine residue found in locally grown dairy feedstuffs. when toxaphene use was curtailed, it was analytically impossible to determine whether dde found in lives..

mutagenic potential of ammonia-related aflatoxin reaction products in a model system

a determination has been made of the mutagenic potential of aflatoxin reaction products following ammoniation of aflatoxin b//1 in a pressure chamber used to decontaminate aflatoxin-contaminated cotton-seed meal. uniformly ring-labeled (**1**4c)-aflaxtoxin b//1 was added to nonlabeled b//1, distributed on an inert carrier and treated with..