对释放入环境的工业污染物数量的关注激励科研人员研制用于检测毒素,特别是重金属的简便而又精确的方法。微生物学家现已提供了一种新的检测毒素和重金属的途径,即利用依据其所处环境中的金属浓度发光或不发光的生物发光细菌。 David Ho...对释放入环境的工业污染物数量的关注激励科研人员研制用于检测毒素,特别是重金属的简便而又精确的方法。微生物学家现已提供了一种新的检测毒素和重金属的途径,即利用依据其所处环境中的金属浓度发光或不发光的生物发光细菌。 David Holmes及其在Clarkson大学(Potsdam,NY)的同事将一种生物发光海洋细菌费氏弧菌(Vibrio fischeri)的发光基因与其它相应于存在铜或汞的生物基因融合。展开更多
Performances and efficiencies of displacement ventilation(DV) and partial ventilation(PV) for industrial halls of different configurations as well as the heat and mass transports within the industrial halls were numer...Performances and efficiencies of displacement ventilation(DV) and partial ventilation(PV) for industrial halls of different configurations as well as the heat and mass transports within the industrial halls were numerically investigated. Three levels of Rayleigh number(5.8×1010, 1.0×1012 and 2.1×1012) and two values of source contaminant flux(5 mg/s and 50 mg/s) were considered. The inlet Reynolds numbers were 2×104, 5×104, 1.5×105 and 4.5×105 for DV and 5×105, 1×106, 2×106 and 4×106 for PV, respectively. From the results, it is concluded that the above parameters have very complex impacts on the conjugated heat and mass transports. From points of view of acceptable indoor air quality and ventilation efficiency, PV at Re=1×106 with side-located sources and 65% of the supply air extracted through floor level outlets is the best choice when Ra=5.8×1010. However, DVs at Re=5×104 and Re=1.5×105with center-located sources and floor-mounted air suppliers are the best choices for Ra=1.0×1012 and Ra=2.1×1012, respectively. When source contaminant flux reaches 50 mg/s, local extraction as a supplement of general ventilation is recommended. The results can be a first approximation to 3D numerical investigation and preliminary ventilation system design guidelines for high-rise industrial halls.展开更多
A laboratory incubation experiment was conducted to elucidate the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels, i.e., 0 ...A laboratory incubation experiment was conducted to elucidate the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels, i.e., 0 (background), 5, 15, 30, 60 and 100 μg-1 soil in the form of either cadmium acetate or cadmium chloride.Application of cadmium as cadmium acetate markedly reduced the soil microbial biomass carbon compared to cadmium applied as cadmium chloride at all the tested levels. Similarly, organic carbon to biomass carbon ratio in the soil was markedly increased by increasing the level of the cadmium in the soil as cadmium acetate,while the change was much smaller in the case of cadmium chloride at the same cadmium levels. The results suggested that due consideration should be given to the source of cadmium while deciding the cadmium levels in experiments.展开更多
Hydrologic features, load of main pollutants and current condition of water quality in Lingdingyang Estuary are discussed by references and monitoring data. Affected by topography, runoff and tide, its dynamic conditi...Hydrologic features, load of main pollutants and current condition of water quality in Lingdingyang Estuary are discussed by references and monitoring data. Affected by topography, runoff and tide, its dynamic condition is very complicated. Different water areas have different hydrologic features. The topography under the water of Lingdingyang Estuary is higher in the northwest than that in the southeast. The shoal alternates with the deep trough within the bay .The distribution of the salinity and the contents of the mud and the main pollutants tally with the topography tendency. Change in water quality goes through four stages. Current condition of water quality is fairly good. Inorganic nitrogen is the primary pollutant, and then phosphorus. Rich in nutrition of nitrogen and phosphorus become a more and more prominent problem.展开更多
A knowledge-based network for Section Yidong Bridge,Dongyang River,one tributary of Qiantang River,Zhejiang Province,China,is established in order to model water quality in areas under small data.Then,based on normal ...A knowledge-based network for Section Yidong Bridge,Dongyang River,one tributary of Qiantang River,Zhejiang Province,China,is established in order to model water quality in areas under small data.Then,based on normal transformation of variables with routine monitoring data and normal assumption of variables without routine monitoring data,a conditional linear Gaussian Bayesian network is constructed.A "two-constraint selection" procedure is proposed to estimate potential parameter values under small data.Among all potential parameter values,the ones that are most probable are selected as the "representatives".Finally,the risks of pollutant concentration exceeding national water quality standards are calculated and pollution reduction decisions for decision-making reference are proposed.The final results show that conditional linear Gaussian Bayesian network and "two-constraint selection" procedure are very useful in evaluating risks when there is limited data and can help managers to make sound decisions under small data.展开更多
文摘对释放入环境的工业污染物数量的关注激励科研人员研制用于检测毒素,特别是重金属的简便而又精确的方法。微生物学家现已提供了一种新的检测毒素和重金属的途径,即利用依据其所处环境中的金属浓度发光或不发光的生物发光细菌。 David Holmes及其在Clarkson大学(Potsdam,NY)的同事将一种生物发光海洋细菌费氏弧菌(Vibrio fischeri)的发光基因与其它相应于存在铜或汞的生物基因融合。
基金Project(2011BAJ03B07)supported by National Twelve Five-year Science and Technology Support Program of ChinaProject supported by the China Scholarship Council+1 种基金Project(51276057,51376198)supported by the National Natural Science Foundation of ChinaProject(CX2014B064)supported by Hunan Provincial Innovation Foundation for Postgraduate,China
文摘Performances and efficiencies of displacement ventilation(DV) and partial ventilation(PV) for industrial halls of different configurations as well as the heat and mass transports within the industrial halls were numerically investigated. Three levels of Rayleigh number(5.8×1010, 1.0×1012 and 2.1×1012) and two values of source contaminant flux(5 mg/s and 50 mg/s) were considered. The inlet Reynolds numbers were 2×104, 5×104, 1.5×105 and 4.5×105 for DV and 5×105, 1×106, 2×106 and 4×106 for PV, respectively. From the results, it is concluded that the above parameters have very complex impacts on the conjugated heat and mass transports. From points of view of acceptable indoor air quality and ventilation efficiency, PV at Re=1×106 with side-located sources and 65% of the supply air extracted through floor level outlets is the best choice when Ra=5.8×1010. However, DVs at Re=5×104 and Re=1.5×105with center-located sources and floor-mounted air suppliers are the best choices for Ra=1.0×1012 and Ra=2.1×1012, respectively. When source contaminant flux reaches 50 mg/s, local extraction as a supplement of general ventilation is recommended. The results can be a first approximation to 3D numerical investigation and preliminary ventilation system design guidelines for high-rise industrial halls.
文摘A laboratory incubation experiment was conducted to elucidate the effects of associated anions on toxicity of cadmium applied to microbial biomass in the red soil. Cadmium was applied at six different levels, i.e., 0 (background), 5, 15, 30, 60 and 100 μg-1 soil in the form of either cadmium acetate or cadmium chloride.Application of cadmium as cadmium acetate markedly reduced the soil microbial biomass carbon compared to cadmium applied as cadmium chloride at all the tested levels. Similarly, organic carbon to biomass carbon ratio in the soil was markedly increased by increasing the level of the cadmium in the soil as cadmium acetate,while the change was much smaller in the case of cadmium chloride at the same cadmium levels. The results suggested that due consideration should be given to the source of cadmium while deciding the cadmium levels in experiments.
文摘Hydrologic features, load of main pollutants and current condition of water quality in Lingdingyang Estuary are discussed by references and monitoring data. Affected by topography, runoff and tide, its dynamic condition is very complicated. Different water areas have different hydrologic features. The topography under the water of Lingdingyang Estuary is higher in the northwest than that in the southeast. The shoal alternates with the deep trough within the bay .The distribution of the salinity and the contents of the mud and the main pollutants tally with the topography tendency. Change in water quality goes through four stages. Current condition of water quality is fairly good. Inorganic nitrogen is the primary pollutant, and then phosphorus. Rich in nutrition of nitrogen and phosphorus become a more and more prominent problem.
基金Project(50809058)supported by the National Natural Science Foundation of China
文摘A knowledge-based network for Section Yidong Bridge,Dongyang River,one tributary of Qiantang River,Zhejiang Province,China,is established in order to model water quality in areas under small data.Then,based on normal transformation of variables with routine monitoring data and normal assumption of variables without routine monitoring data,a conditional linear Gaussian Bayesian network is constructed.A "two-constraint selection" procedure is proposed to estimate potential parameter values under small data.Among all potential parameter values,the ones that are most probable are selected as the "representatives".Finally,the risks of pollutant concentration exceeding national water quality standards are calculated and pollution reduction decisions for decision-making reference are proposed.The final results show that conditional linear Gaussian Bayesian network and "two-constraint selection" procedure are very useful in evaluating risks when there is limited data and can help managers to make sound decisions under small data.
