Environmental protection and precaution are the most frequently considered issues in the recent research fields for our present and future surroundings. However, it seems that these environmental issues were less reflected in local-level development plans, and caused several cases of environmental pollution, therefore it became a major concern of local governments and the communities. The role of a 'Local EIA(Environment Impact Assessment)' can be a core issue for the positive preferences of the local-level development plans. Cases of Local EIA in Germany which have been implied successfully are reviewed to generate a local EIA movement and to produce a guideline for Korean local governments. The local EIA in Germany was broadly commenced in the middle of 1980s, and a decade later it was carried out for over 200 of local governments. To produce a better suggestion for Korean local EIA, comparison and analysis of detail data of the German local EIA was carried out, and tested for fourteen cities in Korea based on five categories: i) assessment subject, ii) assessment procedure, iii) main office for assessment, iv) assessment factor and v) assessment standard. Prior suggestions for greater preference of local EIA in Korea are: it is necessary that I) launch of a support system in central government to help the movement of local government; II) a knowledge-based expert group in local government which has by all means of exclusive responsibility for any action(new application or performance of local EIA) ; III) establishment of 'environmental protection measure' in local government level for environmental precaution based on individual environmental character and values in their communities.
The purpose of this study is in identifying the attraction degree of Seonunsan Provincial Park by quantitative analysis.
For this, landscape slide test was performed by questionaries. And multiple regression analysis and Factor analysis were performed for identifying the attraction degree of users. The attraction degree of natural resources was evaluated by questionaries about the landscape scene of 120 slides which was pictured at the chief visual corridor. So it is considered that tourism route for attracting people into natural characteristic resources should be developed. It is identified once again that factors of 「Naturalness」,「Uniqueness」and 「Mysteriousness」are important in natural landscape. And 16 explanation variables which explain the attraction degree of viewing landscape were classified as 4 factors. Those were defined as 「Ability (FⅠ)」, 「Season harmony (FⅡ)」, 「Simplicity (FⅢ)」 and 「Legibility(FⅣ)」.
It is identified that the variables of FⅠ, mysteriousness, is a representative image which expresses the characteristics of Seonunsan Provincial Park.
Suspended sediment outflows mainly by natural situation and artificial action and affects in down-stream. This research studied suspended sediments origination in forests size and mountain stream for natural situation, density for artificial action, and measured the size and possible quantity of suspended sediments origination and studied obstruction method of the generation by artificial action. As the result, I found that the size of generation is about 2~3% of forest size and the forest size which is affecting bare area of valley is about 1~2ha. In addition, possible outflow segments quantity by artificial facilities is assumed to be maximum 200ton/ha and abstract of mountain incline for mountain development needs minimize bare area valley by make right angle with minimum size.
The purpose of this study was to investigate spatial distributions of total deposition. A total number 79 samples were collected at 17 sampling sites from September 1999 to January 2000. Total (=wet+dry) atmospheric depositions were collected by filtered deposition sampler at sampling site (the Western Part of Kyongsangnam Province). In addition, the deposition of soluble and insoluble fraction was also investigated to find a suitable simplified collection method for a long-term monitoring of total deposition.
The total depositions were measured soluble amount(mm/month), insoluble amount(kg/km2/month), pH, conductivity(E.C.) and eight ionic components. The spatial distribution of deposition flux was to estimated by using a kringing analysis. The 17 sites mean fluxes of water soluble ionic components; SO42-, Cl-, NO3-, Na+, NH4+, K+, Mg2+, Ca2+ were 100.7~315.6kg/km2/month, 30.1~234.3kg/km2/month, 64.4~139.4kg/km2/month, 7.5~68.3kg/km2/month, 10.7~48.7kg/km2/month, 5.6~27.9kg/km2/month, 4.5~17.5kg/km2/month, 27.6~81.7kg/km2/month, respectively.
Photochemical-Trajectory model was used to understand the production of ozone in the atmospheric boundary layer. This model was composed of the trajectory and the photochemical models. To calculate trajectories of air parcels, winds were obtained from the three-dimensional nonhydrostatic mesoscale model (PSU/NCAR MM5V2), and the results were interpolated into constant height surfaces. Numerical integration in the trajectory model was performed by the Runge-Kutta method. The photochemical model consisted of chemical reactions and photodissociation processes. Chemical equations were integrated by the semi-implicit Bulirsch-Stoer method.
We performed our experiments from 21 July to 23 July 1994 during the summer time for Seoul area. During the time of maximum ozone concentration in Seoul, four trajectories of air parcels which traveled from Inchon to Seoul were selected. Ozone concentrations estimated by two models are compared with observed one in Seoul area and the photochemical-trajectory model is better fitted than pure photochemical model. During the selected period, high ozone concentrations in Seoul area were more influenced by transferred pollutants from Inchon than emitted pollutants in Seoul.
Cheeka Peak is a unique site for monitoring the background chemistry and aerosol contents of pristine marine air at mid-latitude. During long-range onshore winds that occur frequently throughout the year, it is predicted to have the cleanest air in the northern hemisphere. Measurements of CO and O3 were conducted at Cheeka Peak Observatory(CPO) on the northwestern tip of Washington state, USA during March 6 ~May 29, 2001. The data have been segregated to quantify the mixing ratio of these species in the Pacific marine atmosphere. Also the marine air masses were further classified into four categories based on 10-day backward isentropic trajectories; high, mid, and low latitude and those which had crossed over the Asian industrial region. The diurnal variation of CO and O3 at CPO showed a similar to tendency of background measurement site. When marine air mass flowed to CPO, CO concentration was lower and O3 was similar or higher than those of total data. The westerly flow from ocean, not easterly from continent occurred the high concentration of CO and O3 at CPO. Using the trajectory segregation of marine air mass, the comparison of concentration according to latitude calculated. the CO concentration of Asian trajectory was lower than other latitudes, O3 concentration was higher.
This study was to evaluate the impact of river runoff and salt intrusion by tide on nutrient balance of estuary during a complete tidal cycle. 24 hours time series survey was carried out during a spring tide July 2001 on a tidal estuary in the Keum river. Three stations(A,B,C) were set along a transect line of about 10km, which linked the lower part of estuary dyke to the subtidal zone. Surface water was sampled simultaneously at each station every hours for the determination of nutrients. Water temperature, pH and dissolved oxygen were measured in situ. Riverine input of silicate and nitrate during ebb tide significantly increased the concentration of all stations. Conversely, during high tide, nutrient concentration were lowered by the mixing of fresh water with sea water. Ammonium nitrogen concentration were higher at intertidal zone(Stn.B) due to sewage inflow to Kyeongpo stream and ammonium release under anaerobic conditions. Also, these results was discussed as a biological component that influences the processes of nutrient regeneration within the estuary. Best correlations were found at lower part of estuary dyke(Stn.A) for salinity against DIN(Y=0.121 Sal.+4.97, r2=0.956) and silicate(Y=0.040 Sal.+2.62, r2=0.785). But no significant correlation was found between salinity and ammonium. Unbalanced elemental ratio(N/P, Si/N and Si/P) depended significantly on the import of nutrients (silicate & nitrate nitrogen) from river and stream. The effect of the tidal cycle and river runoff is important that in determining the extend of the variations in nutrient concentrations at all station.
Effects of physico-chemical factors on the zonation and vertical distribution of benthic microalgal communities in the tidal flats of Youngkwang and Gangjin, Korea, were studied. Concentrations of nutrients were low throughout the study period. A 38 species of benthic microalgae was identified. Most of the algae were pennate diatoms with small size. Cell numbers at silty sediments were higher than sandy sediments, and showed high patchy distribution. Zonal distributions of benthic microalgae showed higher variation from silty sediment than sandy sediments. Benthic microalgae showed vertical migration within the upper few mm of sediment with periodicity closely related to tidal cycles. Maximum cells were observed from 0 mm depth both sandy and silty sediments. Cells of benthic microalgae in the 1 - 2 mm depth decreased after desiccation of sediments. The variation of cells was higher at sandy sediments than silty sediments. Cell numbers of benthic microalgae showed no positive relationships with pH and nutrinets except NH4-N.
This study aimed to obtain the relative formula with the unit treatment cost according to the treatment of a sewage plant in the service area under highway. The following results were obtained. The correlative formula connected to amount of sewage(Q)generation was as follows ; between an annual amount of sale(C) showed Q=19.113·C0.9294, and between the number of users(P) showed Q=2×10-8·P2 - 0.0298·P + 75,666. The correlative formula connected to the treatment cost was as follows ; according to the amount of sewage generation showed S= 3×10-6·Q - 0.2266·Q + 29,895, according to the elimination of BOD(E) showed S= 6×10-5·E2 - 0.6717·E + 27,744, accoding to the annual amount of sale showed S=0.0005·C2 - 4.8013·C + 35,118, with the number of persons(P) using the service area showed S= 2×10-8·P2 - 0.046·P + 48,803.
A Numerical simulation on the thermal flow performance was carried out to propose the incinerator type for the domestic refuses and to investigate the design factor and operating conditions. The SSTI(Standard Stoker Type Incinerator) proposed in this study was modified from the type with central flow. It has the characteristics of good mixing between refuse and hot combustion gas in primary combustion chamber and between unburned gas inflowing and secondary air jet in secondary chamber.
By predictive results, the SSTI was no recirculation zone in secondary chamber so that mixing time was increased with high residence time. It has good characteristics of combustion and low emission. Parametric screening studies have been understood with phenomenon of combustion in incinerator.
The research was performed to compare to the biofilm characteristics and phenol removal efficiency in RBCs(Rotating Biological Contactor) using Rhodococcus sp. EL-GT(single population) and activated sludge(mixed population) as inoculum. Both reactors showed similar tendency on variations of dry weight, thickness and dry density of biofilm. However, the growth of biofilm thickness in 3 and 4 stage of single population reactor has sustained longer than that of the mixed population reactor. Unlike the mixed population reactor, the dry density of biofilm in the single population reactor had a difference between 1, 2 stage and 3, 4 stage. The single population reactor was stably operated without the decrease of phenol removal efficiency in the range of pH 6~9 and 15mM phenol was completely degraded in these pH ranges. But in case of the mixed population reactor, the phenol degradability was dramatically decreased at over 5mM phenol concentration because of the overgrowth and detachment of its biofilm.
This study was investigated to evaluate the effect of the sodium ion and pH on toxicity of dinitrophenol at high concentrations (0.41 to 0.54 mM), over a sodium concentration range of 0.1 mM to 107 mM and over a pH range of 5 to 9. The concentration of sodium ions in the activated sludge mixed liquor seemed to have very little effect on dinitrophenol toxicity. However, lack of sodium in the growth media resulted in a reduction of the dinitrophenol degradation rate by bacterial isolate from the activated sludge culture, which has been identified as Nocardia asteroides. Dinitrophenol inhibition was found to be strongly dependent on mixed liquor pH. The dinitrophenol degradation rate was highest in the pH range of 6.95 to 7.84; at pH 5.94 degradation of 75 mg/L dinitrophenol was significantly inhibited; at pH < 5.77, dinitrophenol degradation was completely inhibited after approximately 30% of the dinitrophenol was degraded.
Anaerobic/aerobic reactor system was used to treat a synthetic wastewater with glucose as carbon sources(0.38˜2.29 kg COD/m3.day) and Acid Red 14(1.05˜24.00 g Acid Red 14/m3.day, color degree of 570˜1710). COD removal efficiency by the anaerobic stage in operation period were above 90 % organic loading rate of 0.38˜2.29 kg COD/m3.day(except, adaptation period) and the removal efficiency of the whole system were above 96 %. The decolorization of the Acid Red 14 was through the alteration of the dye structure(or cleavage of the Azo bond) during the anaerobic treatment. In the A/A system, the anaerobic stage played an essential role in removing both color and COD. In addition it also improves biodegradability of dye for further aerobic treatment. After operation, average MLSS concentration of anaerobic sludge reactor, anaerobic fixed-bed reactor and aerobic fixed-bed reactor were 17100mg/L, 20000mg/L, and 10000mg/L, respectively.
Selective catalytic reduction and selective non-catalytic reduction processes are mainly used to treat nitrogen oxidants generated from fossil-fuel combustion. Especially, the selective non-catalytic reduction process can be operated more economical and designed more simply than the selective catalytic reduction. For this reason, many researchers carried out to increase the removal efficiency of nitrogen oxidants in the condition of low oxygen concentration by using the selective non-catalytic reduction process. However, this study was flue gas contained high oxygen concentration of 20(v/v%) with ammonia as a reducing agent. Moreover, it carried out experiment with many factors that are reaction temperature, retention time, initial NO concentration, NSR(normalized stoichiometric ratio). It was determined optimal operating conditions to improve NO removal efficiency with SNCR process. The De-NOx efficiency was increasesd with NSR, initial NO concentration and retention time increasement. This study has NO removal efficiency over 80% in the high oxygen concentration as well as low oxygen concentration. The injection of reducing agent may be considered for SNCR process and facility operation in 850℃ of optimal condition.
Heavy metals like Mercury and Cadmium cause various kinds of toxicities in the organs of Liver and Kidney. To observe the results of toxicity in the liver, kidney, and serum when the rats were injected subcutaneously with HgCl2 and CdCl2 and sacrificed after 24 hours and 72 hours from the last injection, we measured variation of lipidperoxide values in rat liver homogenate, variation of aspartate aminotransferase and alanine aminotransferase in rat serum. Variation of lipidperoxide values in rat kidney homogenate and variation of BUN in rat serum.
It was found that Mercury and Cadmium administered subcutaneously to the skin in the air could cause the damages of liver and kidney.
Photocatalytic degradation of chlorpyrifos and diazinon, which are extensively used as an organophosphorous pesticide in the agriculture field, has been investigated with UV-radiated TiO2 in aqueous phase. Photodegradation rate was increased with increasing pH of the solution. The removal efficiencies of chlorpyrifos and diazinon were 100% after 200 min in pH 9. Photodegradation followed a pseudo-first-order reaction. The rate constants of chlorpyrifos and diazinon were 0.0160min-1 and 0.0180min-1, respectively. NO3-, PO43-, SO42- and Cl- were found as end products on the photocatalytic degradation of chlorpyrifos and diazinon with TiO2/UV.
Photocatalytic degradation of phenol was carried out with UV-illuminated TiO2- SiO2 in aqueous suspension. TiO2-SiO2 catalysts were prepared by sol-gel method from the titanium isopropoxide and tetraethylorthosilicate at different Ti/Si ratio and some commercial TiO2 catalysts were used as purchased. All catalysts were characterized by X-ray Diffraction(XRD) and BET surface area analyzer. The effect of reaction conditions, such as initial concentration of phenol, reaction temperature and catalyst weight on the photocatalytic activity was studied. In addition, TiO2-SiO2(49:1) prepared by sol-gel method showed higher activity than commercial TiO2 catalysts on the photocatalytic degradation of phenol. The addition of SiO2 into TiO2 hepled to increase the thermal stability of titania which suppressed the formation of anatase into rutile. The photocatalytic degradation of phenol showed pseudo-1st order reaction and the degradation rate increases with decreasing initial phenol concentration.
The absorption of benzene in nonpolar solution was studied in a laboratory-scale of bubble column varying of gas flow rates and gas-to-liquid ratios. A bubble column had a 0.8~1×10-3 m3 total volume (height 1500 mm, diameter 50 mm). Solution analysis was performed by GC-FID and GC-MSD. The objectives of this research were to select the best absorption fluid and to evaluate the mass transfer characteristics under specific conditions of each absorption. The results of this research were follow as:
First, the heat transfer fluid is more efficient than the other nonpolar solution in removing VOC. Second, The benzene removal efficiency improved according to an increasing rate of gas flow. Also, volumetric mass transfer rate of column can be enhanced by increasing gas flow rate. Finally, the relation of gas flow rates, liquid amount, and volumetric mass transfer coefficient was obtained as follows.
Kya=0.5906(Vg/L)0.7611
The following correlation of mass transfer coefficient and efficiency was proposed.
η=0.06078 Kya0.2444