The Sulfur Balance of Incinerators

Municipal refuse usually contains only 0.10-0.15% sulfur. During combustion a minor fraction of the sulfur is released as SO₂, while the major fraction is fixed in the ash, which contains alkaline oxides. Contrasted with coal and heavy fuel oil, municipal refuse is a minor to negligible source of SO₂ air pollution.     

Subacute effects of a phosphorothionate pesticide on mixed function oxidases of wistar rats

Abstract

Subacute oral toxicity of a newly developed phosphorothionate insecticide (2‐butenoic acid‐3‐(diethoxy‐phosphinothioyl) methyl ester), coded as RPR‐2, was studied in male rats by oral (multiple) intubation of low (0.014 mg kg^‐1 day^‐1), medium (0.028 mg kg^‐1 day^‐1), and high (0.042 mg kg^‐1 day^‐1) dose for 90 days. The medium and high dose produced toxic symptoms along‐with some mortality (20%) occurred in the high dose treated rats. The medium and high doses caused significant inhibition in cytochrome P‐450 activity in liver, lung, kidney and brain tissues at 45 and 90 days. The high dose caused significant decrease in cyt.b₅ activity of all the four tissues at 45 and 90 days. Whereas, medium dose brought such effect in liver and lung at 45 and 90 days. Kidney and brain cyt.b₅ activity decreased significantly at 90^th day due to medium dose. Low dose also caused inhibition in cyt.b₅ activity in brain at 90^th day. Cytochrome P‐450 reductase activity was decreased significantly in liver, lung, kidney and brain at 45 and 90^th by the medium and high dose. The results indicated that RPR‐2 had potential to modulate hepatic and extra‐hepatic cyt.P‐450 dependent monooxygenase system of rat due to subacute exposure. These metabolic alterations were quite reversible after 28 days withdrawal of treatment.     

Importance of the vertical nutrient flux for biological production in the equatorial undercurrent region at 30°W

An attempt is made to estimate the effects of vertical transport mechanisms by means of chemical and biological parameters. Compared with coastal upwelling effects (e.g. at Cap Blanc, North-West Africa) the vertical transport mechanisms in the equatorial undercurrent region at 30° W have only a slight effect in terms of their biological consequences. It is concluded that the role played by turbulent exchange in the flow of nutrients is greater than that played by the mean vertical velocity in the undercurrent region at 30° W.     

Performance of a Flue-Fed Incinerator

The various uses of fire in agricultural practice are discussed in a framework of three general purposes: (1) waste disposal, {2) disease control, and (3) land and crop management.In each purpose the use of fire or burning is discussed in relation to the general requirements and to the problems of air pollution control.     

A simulation approach to evolutionary game theory: the evolution of time-sharing behaviour in a dragonfly mating system

Summary The time-sharing behaviour of dragonfly males (Aeschna cyanea, Odonata) at the mating place is investigated. By computer simulation of the males' interactions the expected number of copulations for different strategies is quantified. The simulation results show that a male's mating succes depends on his strategy and that a strategy's specific pay-off depends on the frequency distribution of strategies in the population. Based on these results, a method for the simulation of the evolutionary process is presented. This approach to evolutionary game theory allows the prediction of evolutionarily stable strategies (ESS), even when the system studied is far too complex for an analytical solution. For the time-sharing behaviour of Ac. cyanea males at the mating place the ESS predicted by the simulation approach complies with field observations.     

Thermal degradation of fluorotelomer treated articles and related materials

This study reports the first known studies to investigate the thermal degradation of a polyester/cellulose fabric substrate ("article") treated with a fluorotelomer-based acrylic polymer under laboratory conditions conservatively representing typical combustion conditions of time, temperature, and excess air level in a municipal incinerator, with an average temperature of 1000 degrees C or greater over approximately 2s residence time. The results demonstrate that the polyester/cellulose fabric treated with a fluorotelomer-based acrylic polymer is destroyed and no detectable amount of perfluorooctanoic acid (PFOA) is formed under typical municipal incineration conditions. Therefore, textiles and paper treated with such a fluorotelomer-based acrylic polymer disposed of in municipal waste and incinerated are expected to be destroyed and not be a significant source of PFOA in the environment.     

Mechanisms of electromagnetic interaction with cellular systems

The question of how electromagnetic fields - static or low to high frequency - interact with biological systems is of great interest. The current discussion among biologists, chemists, and physicists emphasizes aspects of experimental verification and of defining microscopic and macroscopic mechanisms. Both aspects are reviewed here. We emphasize that in certain situationsnonthermal interactions of electromagnetic fields occur with cellular systems.