In this study, a full survey of pollutant sources and water quality was conducted, followed by the application of a water quality model (Water Quality Analysis Simulation Program, WASP) to establish strategies of water quality control in Carp Lake, Taiwan. Results of the field investigation show that both point and non-point source (NPS) pollutants were responsible for the poor water quality. The contributions of biochemical oxygen demand (BOD) from point source and NPS pollution were 45.9 and 55.1%, respectively. About 80% of total phosphorus (TP) were contributed by NPS. Additionally, point source and NPS pollution discharged 55.5 and 44.5% of NH 3 -N load, respectively. The Carlson's Trophic State Index ranged from 61.9 to 69.2 showing serious eutrophic problems in Carp Lake. The calculated BOD, NH 3 -N, and TP carrying capacity were approximately 2.8, 0.42, and 0.15 kg per day, respectively. However, the current pollutant loadings are approximately 3.0-5.5 times the calculated carrying capacity. With the help of the calibrated WASP model, remedial strategies for the lake water from short-term to long-term were developed. The completion of the small local sewer system to remove 80% of the point source pollution can serve as a short-term goal while 40-60% of NPS removal by natural treatment systems may serve as a mid-term goal. Furthermore, 80% of both source point and NPS pollution removal can be considered as a long-term strategy. Results of heavy metal analysis show that the enriched sediment would be safe for agricultural applications.

BACKGROUND: Inadequate surface oxidization can potentially destroy the structure and chemical characteristics of the carbon nanotubes (CNTs) and result in loss of sorption capacity and weight. It is necessary to carefully oxidize CNTs using an adequate NaOCl concentration before using it as a sorbent.

This study investigated VOC emissions from the largest petrochemical industrial district in Taiwan and recommended some control measures to reduce VOC emissions. In addition to the petrochemical industry, the district encompasses a chemical and fiber industry, a plastics industry and a harbor, which together produce more than 95% of the VOC emissions in the area. The sequence of VOC emission was as follows: components (e.g., valves, flanges, and pumps) (47%) > tanks (29%) > stacks (15%) > wastewater treatment facility (6%) > loading (2%) > flares (1%). Other plants producing high-density polyethylene (HDPE), styrene, ethylene glycol (EG), gas oil, and iso-nonyl-alchol (INA) were measured to determine the VOC leaching in the district. The VOC emissions of these 35 plants (90% of all plants) were less than 100 tons/year. About 74% of the tanks were fixed-roof tanks that leached more VOCs than the other types of tanks. To reduce leaching, the components should be checked periodically, and companies should be required to follow the Taiwan EPA regulations. A VOC emission management system was developed in state implementation plans (SIPs) to inspect and reduce emissions in the industrial district.

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Carbon nanotubes (CNTs) were grown on micron-sized Al 2 O 3 particles in an atmosphere of methane and hydrogen at 700°C under the catalysis of Fe-Ni nanoparticles that had been deposited on the surface of Al 2 O 3 particles by an electroless plating technique. The individual and competitive adsorption capacities of Pb 2+ , Cu 2+ , and Cd 2+ from aqueous solution by CNTs on Al 2 O 3 particles were studied. The results showed that the adsorption behavior of these metal ions by as-grown CNTs on Al 2 O 3 particles is in good agreement with the Langmuir adsorption model. The maximum individual adsorption capacities of Pb 2+ , Cu 2+ , and Cd 2+ from water by as-grown CNTs on Al 2 O 3 particles are 62.50, 27.03, and 9.30 mg/g, respectively. The CNTs on Al 2 O 3 particles have promising potential applications in removing soluble heavy metals from aqueous solutions.

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This study investigated the IAQ conditions in the field at a hospital in Chia-Yi County in southern Taiwan. Although concentrations of most parameters were still within the regulation values, the concentrations of CO, O3, and HCHO were partially exceeded. We propose a method using an air cleaner with silver-coated zeolite (AgZ) as a possible engineering measure, and there were effective reductions of bacteria and fungi to lower levels with antibacterial effects after 120 hr. Furthermore, this study implies that hospitals should continuously maintain environmental monitoring programs and adopt optimal engineering measures for different needs.