The purpose of this study is to analyze the characteristics of the urban landscape by CG(Computer Graphic) pictures and visibility analysis. In this study, the CG picture was created by using zoning data and DEM(Digital Elevation Model) on Chunchon city. The landscape type was classified into three by cluster analysis using the area rate of the element which constitutes CG picture. Visible analysis used DEM as fundamental data, and was performed by using GIS(Geographic Information System). And the frequency seen on viewshed was classified into five grades. The result of this study are as follows:
1. The area rate of the element which constitutes CG picture was high development restriction zone(43%) in type 1, green land area(39%) in type 2, and city area(24%) in type 3.
2. In the analysis results of GIS visibility analysis, it turns out that Euiam lake is important area on the landscape in all types.
3. The land use of high frequency seen on viewshed was water area, residential area in type 1, development restriction area, park area in type 2, and development restriction zone, water area in type 3.
Hourly data of PM10 concentration collected from nine automatic air quality monitoring stations in Busan from 1999 to 2002 were analyzed to evaluate the spatio-temporal variation and meteorological characteristics of PM10 episodes in Busan metropolitan area. Mean concentrations ranged from 47㎍/m3 to 77㎍/m3. For most stations, mean seasonal hourly concentrations are lowest in summer and highest in spring. PM10 episode above daily mean standard(150㎍/m3) exhibited a maximum frequency at Gamjeondong and a minimum at Dongsamdong, and a maximum in March and a minimum in July and August. The diurnal variation of PM10 episode days is strongly influenced by traffic loads and meteorological conditions.
During the period from April to September 2002, the size distributions of ambient aerosol were measured at the coastal site at Hamduk in Jeju Island. Na+, K+, Mg2+, Ca2+ and Cl- exhibited mostly a bimodal coarse mode size distribution, while ammonium and sulfate were mainly in the fine size range, with maximum at around 0.54㎛. The average molar concentration ratio of ammonium to sulfate for fine particles was equal to 2.0±0.9. Nitrate was evenly found in both the coarse and fine modes. Elements like Al, Fe, Cu, Mg, Na, Ti, Sr and Mn were dominant in coarse particles, with the maximum at around 5.25㎛. S and Pb were mainly in the submicrometer size range. Other elements with a fine and coarse modes were V, Ni, Cu, Ba and Mo. The patterns of the size distributions of trace elements measured at the downtown in Jeju City were very similar to those at the coastal site in Hamduk. However, the amplitude of size fractional concentrations at Jeju City was narrower than that at Hamduk. While the mass median diameters for the chemical species originated from the natural origin such as marine and crust were relatively large, those for ammonium, sulfate, S and Pb were very small.
Adsorption on goethite of individual component from a solution containing phosphate, sulfate, or copper ion was investigated. Competitive adsorption in the binary and ternary solution systems composed of phosphate, sulfate, and copper ions was also investigated. In competitive adsorption systems with phosphate and sulfate ions, the presence of phosphate ion reduced the adsorption of sulfate ion largely. On the other hand, the presence of sulfate ion caused only a small decrease in phosphate adsorption. This result suggests that phosphate ion is a stronger competitor for adsorption on goethite than sulfate ion, which is consistent with the higher affinity of phosphate for the surface compared to sulfate ion. Compared to the results from single-sorbate systems, adsorption of copper ion in the binary system of sulfate ion and copper ion was found to be enhanced in the presence of sulfate ion. Addition of sulfate ion to the binary system of copper ion and phosphate ion resulted in a small enhancement in copper sorption. This result implies that the presence of sulfate ion promotes adsorption of the ternary complex FeOHCuSO4. The adsorption isotherms could be well described by the Langmuir adsorption equation.
The adsorption behaviors of strontium and cesium ions on fly ash, natural zeolites, and zeolites synthesized from fly ash were investigated. The zeolites synthesized from fly ash had greater adsorption capabilities for strontium and cesium ions than the original fly ash and natural zeolites. The maximum adsorption capacity of synthetic zeolite for strontium and cesium ions was 100 and 154 mg/g, respectively. It was found that the Freundlich isotherm model could fit the adsorption isotherm. The distribution coefficients (Kd) for strontium and cesium ions were also calculated from the adsorption isotherm data. The distribution coefficients decreased with increasing equilibrium concentration of strontium and cesium ions in solution. By studying the removal of cesium and strontium ions in the presence of calcium, magnesium, sodium, potassium, sulfate, nitrate, nitrite, and EDTA (in the range of 0.01 - 5 mM) it was found that these coexistence ions competed for the same adsorption sites with strontium and cesium ions.
The aim of this study is, firstly, to find out what kinds of inorganic species are produced in the photocatalytic oxidation of ammonium-nitrogen containing water and, secondly, to seek the influence of anion for the photocatalytic oxidation of ammonium contained compounds. The photoenergy above 3 eV(λ<415 nm) was effectively absorbed by TiO2 and TiO2/polymer was used to be oxidized NH4-N in wastewater to NO3-N. Existing the anion as Cl-, the rate of photocatalytic oxidation decreased regardless of other condition. This result showed that the chloride ions reduced the rate of oxidation by scavenging oxidizing radical species as OH- and OCl-. Some of the added ion might have blocked the active sites of the catalyst surface, thus deactivated the catalyst.
This study was carried out to check changes of components in the slaughter waste by the bacteria isolated from slaughter wastes from Gyungnam Province from May to June 2000, and to find useful organism for treatment of the waste. Bacteria used in this study were Aeromonas hydrophila, as the dominant of the waste. Optimum conditions for bacterial culture were obtained as the temperature of 35℃, pH 6.5, and shaking of 120 rpm in nutrient broth. The mean values of dissolved oxygen was 4.14 ㎎/l; biochemical oxygen demand, 1731.21 ㎎/l; ratio of BOD/COD, 0.53-0.64; ratio of T-P/T-N, 1.0-1.41; and viable counts of the waste, 5.47×107 CFU.
Little change in total nitrogen observed by 36 hr of the culture. The largest amount of increasing NH4+-N was observed in the sample that 10% of the waste added in nutrient broth with A. hydrophila showing the value of 29.19 ㎎/l at the beginning to 570.36 ㎎/l by 36 hr of culture. However, the highest increasing ratio between initial amount and finals at 36 hr of culture showed as 41.6 times when 3% of the waste added. NO3--N was decreased showing the value of 71.27 ㎎/l to 32.14 ㎎/l by 24 hr of culture with the organism when 10% of the waste added in nutrient broth. Total phosphorus was decreased showing the value from 188.74 ㎎/l to 101.41 ㎎/l after 12 hr of culture with the organism when 5% of the waste added in nutrient broth, while T-P was decreased gradually by 24 hr of culture from 193.8 to 101.4 ㎎/l when 10% of the waste added.
This study was conducted to investigate anoxic-RBC (rotating biological contactor) and its application in advanced municipal wastewater treatment process to remove biologically organics and ammonia nitrogen. Effluent COD and nitrogen concentration increased as the increase of volumetric loading rate. But, the concentration changes of NO2--N and NO3--N were little, as compared to COD and NH4+-N.
When the volumetric loading rate increased, COD removal efficiency and nitrification appeared very high as 96.7~98.8% and 92.5~98.8%, respectively. However, denitrification rate decreased to 76.2~88.0%. These results showed that the change of volumetric loading rate affected to the denitrification rate more than COD removal efficiency or nitrification rate.
The surface loading rates applied to RBC were 0.13~6.01g COD/㎡-day and 0.312~1.677g NH4+-N/㎡-day and they were increased as the increase of volumetric loading rate. However, the nitrification rate showed higher than 90%.
The thickness of the biofilm in RBC was 0.130~0.141㎜ and the density of biofilm was 79.62~83.78㎎/㎤. They were increased as surface loading rate increased. From batch kinetic tests, the kmaxH and kmaxN were obtained as 1.586 g C/g VSS-day, and 0.276 g N/g VSS-day, respectively.
Kinetic constants of denitrifer in anoxic reactor, Y, ke, Ks, and k were 0.678 ㎎ VSS/㎎ N, 0.0032 day-1, 29.0 ㎎ N/ℓ, and 0.108 day-1, respectively. P and Ks values of nitrification and organics removal in RBC were 0.556 g N/㎡-day and 18.71 g COD/㎡-day, respectively.
In this study, it was performed using submerged nonwoven bioreactor(SNBR) for removal of organic matter, nitrogen and phosphate under different aeration intervals(intermittent aeration). We applied the SNBR at the cheap nonwoven fiber module instead of the expensive membrane. The SNBR was mainly made up of an activated sludge reactor and a transverse flow nonwoven module, with an innovative configuration being in application between them. In case of sewage, the aeration conditions experimented consist of continuous aeration and 60min/60min, 120min/60min, 120min/120min of aeration/nonaeration time intervals, respectively. In case of landfill leachate, the intermittent aeration condition was 120min/120min at aeration/nonaeration. Consequently, a high COD removal rate (about 94%) was achieved in sewage and leachate. Although nutrient removal rate was relatively high without any additional chemicals.
We studied the relationship between a civil affair occurrence of bad smell and meteorological conditions around Seongseo district for recent 2 years. The results were as follows;
(1) The civil affair occurrence days of bad smell were concentrated from May to August.
(2) Daily mean temperatures were mostly 20~28℃ and daily mean relative humidities were 60~80%.
(3) Wind speeds were mostly less than 2m/s(75%), and wind directions were southerly winds(50%). It was hardly occurred for relatively well-ventilated conditions in cases of wind speeds 2m/s over.
And the Lagrangian particle dispersion model were used to figure out the transport route in a civil affair occurrence days of bad smell. It was found that the south-western winds transported the bad smelling materials from Jungni-dong(the place of source) to the housing complex located along a piedmont district.
The genetic algorithm is investigated for parameters estimation of SED (storage - effective drainage) model from the Wi-stream watershed in Nakdong river basin. In the practical application of model, as a number of watershed parameters do not measure directly, it is desirable to make a good estimation from the known rainfall and runoff data. For the estimation of parameters of the SED model using the genetic algorithm, parameters of Green-Ampt equation(SM, Ks) for the estimation of an effective rainfall and initial storage(yin) used in SED model are obtained a regression equation with 5, 10, 20 days antecedent precipitation. And as a consequence of computation, the parameters were obtained to satisfy the proposed objective function.
From the comparison of observed and computed hydrographs, it shows a good agreement in the shape and the rising limb, peak, falling limb of hydrograph, so the SED model using the genetic algorithm shows a suitable model for runoff analysis in river basin.
Pesticides were extracted from samples with 70% acetone and methylene chloride in order, and then cleaned up via open-column chromatography apparatus packed with florisil, and finally analyzed simultaneously the organophosphorus pesticides using GC/NPD. Ultra-2 and Ultra-1 fused silica capillary columns were used to separate and identify the products. Recovery of most analytes from soybean sample, taken from pesticide residues well, was greater than(80%) for all except(6) analytes. This method can simultaneously determine multiple pesticides with a high degree of accuracy and precision.
We report the distributions of Sb and As in the surface sediment of the Yellow Sea and the coastal areas of Korea. The mean concentrations of Sb and As range from 0.68 ppm to 1.01 ppm and from 7.4 ppm to 15.8 ppm, respectively, and show relatively the high concentrations at the coast of Weolseong in the East Sea for Sb and at the coast of Gadeok Island in the South Sea for As. This may be due to the anthropogenic input of these elements via river and atmosphere from industry complex and agriculture regions around the study areas. Because of the difference of clay to silt proportion, the correlation between silt plus clay contents and Sb, As in the coastal surface sediment of Korea is not shown, the concentrations of Sb and As vary widely for the sample in which the silt plus clay contents are the same. Therefore, we suggest that the distribution patterns of Sb and As in surface sediment of the Yellow Sea and the coastal areas of Korea are mainly controlled by the anthropogenic inputs and the sediment characteristics. On the other hand, the Sb concentrations are lower than those of the lowest effect level which is the standard of judgment for contamination, while the As concentrations are higher than those of the lowest effect level. This implies that the surface sediments of the Yellow Sea and the coastal areas of Korea are considerably contaminated for As.
To examine whether salt stress would alter or not contractility of isolated rat aorta, under anesthesia with sodium pentobarbital(50 mg Kg-1 i.p.), male Sprague Dawley rats(300-330 g) were subjected to 0, 50, and 150 mM of sodium chloride at 37℃ for 60 min. where as the sham group was left at modified Krebs-bicarbonate solution.
To measure contractile response of vascular ring preparation isolated from rat was determined in organ bath and was recorded on physiograph connected to isometric transducer. And the strip was checked for expression of heat shock protein(Hsp) by Western blotting. One, three and eight hours later, we measured vascular contractility of isolated rat aorta treated with KCl, phenylephrine from organ bath study.
The dose-vascular responses of potassium chloride and phenylephrine showed a little augmentation by NaCl concentration in the strips exposed to NaCl for 8 hours. And the response of relaxation induced by nitroprusside and acetylcholine was not influenced by NaCl stress in isolated aorta ring for 8 hours, respectively.
Expression pattern of Hsp 70 of vascular muscle in isolated rat aorta showed a little increase in 150 mM NaCl group at 8 hours after NaCl treatment but not at 3 hours, and Hsp 60 expression of rat aorta was markedly increased in 50 mM NaCl group at 8 hours after NaCl treatment.
Taken together, NaCl induced dose- and time dependent accumulation of the Hsp but not affected contraction of rat aorta. These data suggest that short term high salt stress was not sufficient to induce hypertension of rat aorta..