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Chlorpyrifos is an organophosphorus insecticide used to control insect pests in soil. The fate of chlorpyrifos in soils under different moisture regimes is of interest because application directions specify soil-surface treatments for a number of agricultural and urban pests. Chlorpyrifos was degraded rapidly in all air-dry soils and slightly more slowly in soils at field capacity and/or under submerged conditions. Degradation rates were influenced by clay-catalysed hydrolysis under air-dry conditions and neutral or alkaline hydrolysis under submerged conditions. Degradation was faster in Bellary soil (chromic haplustert) and slower in Chettalli soil (ustic palehumult) under all three moisture regimes. The calculated half-lives ranged from 1.6 to 10.0, 5.2 to 22.0 and 8.7 to 25.1 days under air-dry, field capacity and submergence respectively at an application rate of 10 mg kg -1 .

Human activities such as industrial development, burning of fossil fuels, deforestation and even agriculture practices are changing the composition of Earth's atmosphere. There is a growing concern that greenhouse gases released by these activities, such as carbon dioxide, may cause global warming which, in turn, would have dramatic social, economic and political impacts. The paper examines the global warming contribution of automobiles in Canada and compares various alternative transportation fuels in terms of their emissions of greenhouse gases and global warming potential. Energy conservation, improved fuel economy, and the use of certain alternative transportation fuels can significantly reduce the emissions of greenhouse gases from automobiles. Although automobiles in Canada make a rather small contribution to overall emissions of greenhouse gases in the global context, reducing the emissions of greenhouse gases seems to be a step in the right direction. Many individual measures, each having a modest impact on greenhouse gas emissions, can have a dramatic impact on the rate of climatic change when combined.

A study has been conducted on the drying of lime mud and the concurrent oxidation of sodium sulphide in the mud. The experiments were done using a 6″ dia spouted bed of coarse inert particles (cement clinker and limestone; —4 + 10 mesh) with continuous feed of lime mud. A range of inlet gas temperatures, from 260°F to 400°F, was studied. A high degree of sulphide oxidation was achieved by this method over the entire temperature range, sulphide removal being in excess of 80% in all runs and as high as 98% in some. An analysis of the economic feasibility of drying lime mud in a spouted bed indicates that the process has good potential both as a method for drying lime mud prior to calcining and for control of hydrogen sulphide emission from lime kilns operated at kraft pulp mills. On a fait une etude du sechage de la boue de chaux et de l'oxydation simultance du sulfure de sodium dans celle-ci. On a employe pour ces experiences un lit fluidise avec giclage (spouted bed); il etait forme de grosses particules inertes (ciment non broye et pierre calcaire, -4 + 10 mailles) et alimente d'une maniere continue avec de la boue de chaux. On a etudie, pour le gas introduit, une echelle de temperature variant entre 260°F et 400°F. Oa a obtenu par cette methode un fort degred'oxydation du sulfure sur toute l'echelle de temperature; l'elimination du sulfure a excede 80% dans toutes les experiences et a měme atteint 98% dans certaines d'entre elles. Une analyse de la rentabilite du sechage de la chaux dans un lit fluidise avec giclage indique que ladite methode est pleine de promesses a la fois pour secher la boue de chaux, avant de la calciner, et pour minimiser l'emission d'hydrogene sulfure provenant des fours a chaux dans les moulins a papier de pǎte au sulfate.

Two sub-bituminous coals, a bituminous coal and a reject coal of 55% ash were gasified with steam and air in a 0.31-m dia. reactor operated in the fluidized and spouted bed modes. Inert beds of 1.1 mm dia. Ottawa sand and 2.1 mm dia. gravel provided stable fluidization and spouting respectively, at superficial velocities in the range 1.3–1.6 m/s. Coals of 1.19–3.36 mm diameter were fed to the gasifier at rates up to 45 kg/h and a range of air/coal ratios. For a given coal, results in the two systems were basically similar, although differences in gas heating value, gas yield and thermal efficiency were noted for some coals. On a gazeifie deux charbons subbitumineux, un charbon bitumineux et un rejet de charbon comprenant 55% de cendres; en employant de la vapeur d'eau et de l'air dans un reacteur de diametre 0.31 m et pouvant fonctionner en lit fluidise et en lit “spoute”. Des lits inertes formes de sable d'Ottawa de 1.1 mm de diametre et de gravier de 2.1 mm de diametre ont fourni respectivement une fluidisation et un spouting stables a des vitesses superficielles variant entre 1.3 et 1.6 m/s. On a alimente le gazogene a des debits allant jusqu'a 45 kg/h et pour diverses valeurs du rapport air/charbon. Les resultats dans les deux systemes, pour un charbon donne, se sont averes essentiellement semblables, bien qu'on ait observe des differences dans la valeur calorifique du gaz, le rendement en gaz et l'efficacite thermique pour certains des charbons.

A dilatometric technique was used to determine the total evaporation time of individual drops of furan, isopentane and cyclopentane as they rose in water. The values of total evaporation time were predicted reasonably well for each system by a different equation than was used to correlate the evaporative data for the initial 10% of the evaporative process as reported in Part I of this study. The total evaporation time data were also compared with the correlations given by Klipstein (1), by Sideman and Taitel (2) and with the correlation which was found by the authors to best fit the total evaporative data for the three systems. In agreement with Klipstein (1), the correlation for the overall heat transfer coefficient was found to be one of the form, qA = Cd12.0δt. The rate of rise of an evaporating drop for the conditions used in this study was found to be nearly equal to the instantaneous terminal velocity. On a utilise une technique dilatometrique pour determiner le temps de l'evaporation totale de gouttes simples de furane, d'isopentane et de cyclopentane, au moment ou elles s'elevent dans l'eau. On a trouve que les valeurs pour le temps d'evaporation totale etaient predites d'une maniere assez satisfaisante pour chaque systeme, au moyen d'une equation differente, laquelle etait utilisee pour la correlation des resultats d'evaporation dans le cas du premier 10% du precede d'evaporation, tel que rapporte a la Partie 1 du present travail. On a aussi compare les resultats du temps d'evaporation totale avec les correlations mentionnees par Klipstein (1), et Sideman et Taitel (2) ainsi qu'avec la correlation que les auteurs ont trouve convenir le mieux aux resultats d'evaporation totale pour les trois systemes. Conformement a l'enonce de Klipstein (1), on a trouve que la correlation pour le coefficient de transfert total de la chaleur etait de la forme, qA = Cd12.0δt. La vitesse d'elevation d'une goutte qui s'evapore dans les conditions utilisees dans cette etude s'est averee presque egale a la velocite finale et instantanee.