Nanosized titania sol has been produced by the controlled hydrolysis of titanium tetraisopropoxide(TTIP) in sodium bis(2-ethylhexyl)sulfosuccinate(AOT) reverse micelles. The physical properties, such as crystallite size and crystallinity according to R ratio have been investigated by FT-IR, XRD and UV-DRS. In addition, the photocatalytic degradation of bromate has been studied by using batch reactor in the presence of UV light in order to compare the photocatalytic activity of prepared nanosized titania. It is shown that the anatase structure appears in the 300～600℃ calcination temperature range and the formation of anatase into rutile starts above 700℃. The crystallite size increases with increasing R ratio. In the photocatalytic degradation of bromate, the photocatalytic decomposition of bromate shows the decomposition rate increases with decreasing initial concentration of bromate and with increasing intensity of light.

The purpose of this study was to investigate the pollutions of water qualities in 30 water samples from Nakdong River, Western Nakdong River, and Suyoung Stream. COD, BOD, T-N and negative ions(F-, Cl- NO3-, SO42-) of water samples were analyzed and the correlationships between water qualities were examined. The mean concentrations of COD(20.26ppm), BOD(25.36ppm), and T-N(18.05ppm) were the highest in the water sample of Suyoung Stream among the three streams and those of F-(0.25ppm), Cl-(27.70ppm), and SO2-(37.66ppm) in Western Nakdong River, that of NO_3,(10.81ppm) in Nakdong River. The water quality of Suyoung Stream was the worst among the three streams in Pusan area. The correlationships between water qualities were as follows ; BOD and COD showed very high correlationship(correlation coefficient, r=0.97), SO42- and NO3- did high one(0.75), and NO3- and COD, BOD did relatively high ones(0.56 and 0.48, respectively).

This study was performed to investigate the riverbed structure and the pollution type in Nakdong River, Western Nakdong River, and Suyoung Stream. Sediment and water samples were collected at 15 in Nakdong River, 7 in Western Nakdong River, and 8 sites in Suyoung Stream from February 20, 1997 to June 15, 1997. The depth distributions of sampling sites in the three streams were measured and heavy metals(Cd, Pb, Cr, Cu) and pesticides in sediments and COD, BOD, and total nitrogen(T-N) in water samples were analyzed. The deepest and the shallowest sites were site 11(11.58m) and 9(3.35m) in Nakdong River, site 7(6.25m) and 4(2.06m) in Western Nakdong River, and site 8(2.89m) and 1(0.61m) in Suyoung Stream, respectively. The mean concentration of Cd(45.79ppm) was higher in the sediment of Western Nakdong River than in other two streams and those of Pb(76.25ppm), Cr(48.13ppm), and Cu(77.50ppm) were higher in the sediment of Suyoung Stream than in other two streams. Pesticides(1 kind of organophosphonis and 3 kinds of organochlorine pesticide) were detected only in the sediment of Western Nakdong River. The mean concentrations of COD(20.26ppm), BOD(25.36ppm), and T-N(18.05ppm) were higher in the water sample of Suyoung Stream than in other two streams.

Organophosphate pesticides were extracted with 70% acetone and then transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil The final extract was analyzed by gas chromatography with nitrogen-phosphorus detector(GC/NPD). Recoveries of the 18 organophosphate pesticides were ranged from 88.7% to 100.0% for the narrow-bore capillary GC(Ultra-2). The minimum detectable level of this analytical method was 0.019 - 0.035 ㎎/㎏. Sample throughput(extraction, open-column chromatography, and GC analysis) was decreased considerably (8h per sample).

Cation exchange distribution coefficients of poly(dithiocarbamate) were presented for Cd^2+, Cr^3+, and Pb^2+ in HCl. The distribution coefficients were determined by using the batch method. Based on these distribution data, the separation possibilities of the heavy metal ions were discussed. The distribution coefficients of three heavy metal ions on dithiocarbamate resin were decreased as HCl concentrations were increased. The selective separation of Cr^3+ and Cd^2+ was possible by using 0.1 M HCl in dithiocarbamate resin and the reproducibility test showed that the average absorptivity of resin was 90% in the case of Cd^2+ ion by the column method.