Fourteen samples of settled dust from two factories processing rice and wheat straw near Shanghai.China, were examined by dilution plating for total bacteria, gram-negative bacteria, thermophilic actinomycetes, and fu...Fourteen samples of settled dust from two factories processing rice and wheat straw near Shanghai.China, were examined by dilution plating for total bacteria, gram-negative bacteria, thermophilic actinomycetes, and fungi.They were also examined for atlatoxin endotoxin, and potential to stimulate production of human interleukin 1β (IL-1β) and to consume complement.The concentrations of total microorganisms were consistently greater than 10~7 CFU/g and ranged from 10~7 to 10~9 CFU/g.In general, the level of microbial contamination was greater in the hay dust samples than in the rice dust samples, with bacteria being the most numerous microorganisms observed followed by molds, thermophilic actinomycetes, and yeasts.The predominant fungi were species of Aspergillus, Cladosporium, Penicillium.Trichosporon, and Cryplococcus.No significant levels of aflatoxin were observed and the isolates of A.flavus examined lack significant aflatoxigenic potential.The levels of microorganisms in these samples, the types of organisms found, and the inflammatory mediators such as endotoxin suggest that workers exposed to these dusts may be at risk for respiratory illness. 1990 Academic Press.Inc.展开更多
A 3-D time dependent, dimensionless coordinate numerical model for flow-salt-sediment movement in tidal estuaries is briefly described. The irregular body of water being considered on to a unit cube in this article, s...A 3-D time dependent, dimensionless coordinate numerical model for flow-salt-sediment movement in tidal estuaries is briefly described. The irregular body of water being considered on to a unit cube in this article, so it can be applied equally well to large tidal ranges. The transformed set of equations are then solved by finite difference techniques using a variable grid designed to retain the second order accuracy of space grids. The suspended sediment part of the model employs the conceptions of the rate of erosion-siltation in the bottom boundary conditions, the parameters in which are defined by combining analysis of laboratory data and model data. The effective settling velocity formula, which is obtained in Changjiang estuary, is applied in the part of computing suspended sediment concentration. The model had been verified with the field data from Changjiang estuary. The results show that the model can be used to simulate the movement of flow-salt-sediment in tidal estuaries.展开更多
文摘Fourteen samples of settled dust from two factories processing rice and wheat straw near Shanghai.China, were examined by dilution plating for total bacteria, gram-negative bacteria, thermophilic actinomycetes, and fungi.They were also examined for atlatoxin endotoxin, and potential to stimulate production of human interleukin 1β (IL-1β) and to consume complement.The concentrations of total microorganisms were consistently greater than 10~7 CFU/g and ranged from 10~7 to 10~9 CFU/g.In general, the level of microbial contamination was greater in the hay dust samples than in the rice dust samples, with bacteria being the most numerous microorganisms observed followed by molds, thermophilic actinomycetes, and yeasts.The predominant fungi were species of Aspergillus, Cladosporium, Penicillium.Trichosporon, and Cryplococcus.No significant levels of aflatoxin were observed and the isolates of A.flavus examined lack significant aflatoxigenic potential.The levels of microorganisms in these samples, the types of organisms found, and the inflammatory mediators such as endotoxin suggest that workers exposed to these dusts may be at risk for respiratory illness. 1990 Academic Press.Inc.
文摘A 3-D time dependent, dimensionless coordinate numerical model for flow-salt-sediment movement in tidal estuaries is briefly described. The irregular body of water being considered on to a unit cube in this article, so it can be applied equally well to large tidal ranges. The transformed set of equations are then solved by finite difference techniques using a variable grid designed to retain the second order accuracy of space grids. The suspended sediment part of the model employs the conceptions of the rate of erosion-siltation in the bottom boundary conditions, the parameters in which are defined by combining analysis of laboratory data and model data. The effective settling velocity formula, which is obtained in Changjiang estuary, is applied in the part of computing suspended sediment concentration. The model had been verified with the field data from Changjiang estuary. The results show that the model can be used to simulate the movement of flow-salt-sediment in tidal estuaries.