간행물

한국환경과학회지 KCI 등재 Journal of Environmental Science International

권호리스트/논문검색
이 간행물 논문 검색

권호

제4권 제2호 (1995년 6월) 14

1.
1995.06 서비스 종료(열람 제한)
Identified 7 species of the genus Prorocentrum which have been obtained from the southern coast area for 4 years from 1990 to 1994 can be summarized as followed. P.balticum is rare species, causing a red tide, and P.dentatum, P.micans, P.minimum, P.triestinum are cosmopolitan species often causing a red tide in the study area. P.gracile and P. lima are very rarely showed up, the former is recorded at first in domestic and later is benthic attached species which has diarrheic shellfish poison.
2.
1995.06 서비스 종료(열람 제한)
The comparision of sunshine duration meter was carried out on the roof of Korea Meteorological Research Institude by comparing pyrheliometer(Eppley NIP model) to sunshine duration meter(Reflection type) during from Nov. 8, 1989 to Feb. 19, 1990. In the observation period, daily mean sunshine duration time difference of Jordan sunshine duration meter way recorded 0.47hour and Reflect sunshine duration meter was recorded 0.39hour. More than one hour time difference was observed 15 cases by Jordan sunshine duration meter and 11 cases by Reflect sunshine duration meter.
3.
1995.06 서비스 종료(열람 제한)
Based on the Results of Marine Meteorological and Oceanographical Observations (1966∼1987), the phenomenon of chimney is found as a candidate for the formation of the Japan Sea Proper Water (JSPW). The chimney phenomenon occurs twelve times during 1966∼1987. The water types in the chimney denoting the deep convection are similar to those of the JSPW, 0∼1 ℃ in potential temperature, 34.0∼34.1‰ % in salinity and 68∼80 cl/t in potential thermosteric anomaly from the sea surface to the deep layer. The static stabilities in the chimney stations are unstable or neutral. This indicates that the winter time convection occurs. The JSPW sunken from the surface layer of chimney in winter spreads out under the Tsushima Warm Current area, following the isosteric surface of about. 76 cl/t in potential therniosteric anomaly. The formation of the deep water of the JSPW is mainly affected by the cooling of the sea surface than the evaporation of winds because the temperature and the salinity on the isoteric surface of about 76 cl/t in potential thermosteric anomaly are cold and low. The phenomenon of chimney occurred in here and there of the area in the north of 40˚ 30` N, west of 138°E. This suggests that the deep water of the JSPW is formed not in a limited area but. probably in the overall region of the northern open ocean.
4.
1995.06 서비스 종료(열람 제한)
The quantitative estimations of the stratification - destratification(SD) phenomena in Deukryang Bay, Korea have been carried out based on the data of wind speed, heat flux through the sea surface and tidal current amplitude. To find out the main factors causing SD, we introduce the rate of energy balance of the surface heat flux, tidal and wind stirring proposed by Simpson and Hunter(1974). The calculated potential energy of three terms are compared, from which the energy of wind stirring effect was one order smaller than the heat flux and the tidal stirring. Using the results, we complement time integration of the potential energy with the several ε values of 0.010∼0.014 at interval 0.001 and with wind speeds of 1.5 and 2.0 times larger than observation values at land. It shows that the variation of SD phenomena in the bay mainly depended on tidal stirring and sea surface heating in summer if there is no exceptionally strong wind event like Typhoon. The stratification become to be formed from about 5 July although the stratification a little decreases during the second spring tidal period of middle of July.
5.
1995.06 서비스 종료(열람 제한)
A numerical model has been developed to predict the deposition of air pollutants considering canopy effect. In this model, the deposition velocity is calculated using the deposition resistances(aerodynamic resistance, viscosity resistance, surface resistance). Using the results, a comparative study was made between the model calculation and observation results The calculated daily variation of deposition resistances and in daytime most of the model cases are well agreed with observation results, and a slight difference was found in nighttime. From the results, it is suggested that the present model is capable of estimating the deposition velocity of air pollutants considering characteristics of canopy layer.
6.
1995.06 서비스 종료(열람 제한)
To predict reasonably the movement and the concentration of the pollutants in the coastal area. A simulation model should be prepared considering detail topography with land-sea and the urban effects, and the resolution near the source. The explicit method can not be applied due to the unstability of the numerical calculation in high horizontal-grid resolution, while the ADI scheme satisfied with the high horizontal grid resolution and can be used in the fine mesh system which shows the detail topography, atmospheric flow The ADI method which studied the high horizontal grid resolution was excellent. The two dimentional model used in the study using ADI method is proved as a reasonable model to predict the wind field in any small scale area including mountainous coastal urban area.
7.
1995.06 서비스 종료(열람 제한)
This paper presents effective simulation of the dispersion of thermal discharge which can be relesed at Boryong power plant. Applied numerical models are finite difference method for hydrodynamic analysis and Masch-model comprised of conditions for ambient current velocity. Application of these models is done in Cheonsu Bay. Summing up the results of this study are as follows; 1. It is found that the result for measurement of temperature appears high at southwardly Songdo on flood. The reason is that tidal currents which flowed north direction were accompanied with southwardly dispersed thermal discharge. A minute particle of thermal plume has a tendency to dispers inward Deacheon Bay. 2. According to the results of numerical experiment, maximum distance for thermal discharge dispersion appeared 10.8㎞ at lower part and 8.6㎞ at upper part with power plant outlet as starting point. 3. Comparative the numerical simulation and Airbone Multispectral Scanner indicated that thermal discharge should be verified separative phenomena. The simulated results were compared with field data set showing good agreement. It is concluded that these model can be simulated well.
8.
1995.06 서비스 종료(열람 제한)
Flocculation kinetics using ferric nitrate as a coagulant to coagulate kaolin clay in water was examined as a tool to investigate the effect of low temperature under tightly controlled treatment conditions. Both the particle size distribution data obtained from Automatic Image Analysis (AIA) system and the on-line measurement of the degree of turbidity fluctuation in a flowing suspension by Photometric Dispersion Analyzer (PDA) were used to measure flocculation kinetics. Results show that cold water temperature had a pronounced detrimental effect on flocculation kinetics. For improving flocculation kinetics at low water temperature, maintaining constant pOH to adjust water chemistry for temperature changes was found to be partially effective only in the more acidic pH range studied.
9.
1995.06 서비스 종료(열람 제한)
A lot of sludges occur during an activated sludge treatment process of the washing wastewater and by-product waste in the cuttlefish processing manufacture. The sludges give also out a bad smell, and their amicable reclamation is very difficult because of the limited area of the filling-up. To reduce the heavy weight and large volume of the sludges, they was burning up. After the burning up at 350℃ for 2hrs the weight(volume) of the sludges were reduced to 5% level of the initial value. In contents of the bad heavy metals for human after the burning up, cadmium and lead metal were slightly detected, while mercury and the bad others not detected.
10.
1995.06 서비스 종료(열람 제한)
Design approach of Upflow Anaerobic Sludge Blanket(UASB) process based on the biological kinetic parameters are known to be very difficult since the characteristics of the granular sludge depends on the type of wastewater and size distribution of the granular sludge also depends on the upflow velocity in the UASB reactors. Furthermore, industrial wastewater containing toxic substances has been treated by UASB process without the clear knowledge of toxic effects on the granular sludge. Hence, the present research was aimed on the intensive evaluation of biological kinetic parameters of the granular sludge in UASB reactor with and without toxic substance of 2,4-dichlorophenol in order to present the basic design measures for UASB process design. The results could be summarized as follows. The biological kinetic parameters(k and Ks) considerably varied with the granular size of the sludge. Generally, the k and ks values of the granular sludge increased with the particle size of the granule. The biological kinetic parameters(k and Ks) of the granular sludge obtained from batch test were not applicable to design purpose of UASB process due to substrate diffusional limitation into the granular sludge in the completely mixed UASB reactors. The toxic effects on k and Ks greatly varied with the granular size. And as the toxicant concentration increased, the k value decreased while the Ks value increased. Inhibition constant(ki) for k with the toxicant of 2,4-dichlorophenol varied from 0.5 to 2.3 depending on the granular sizes while the inhibition constant(Ki) for Ks varied from 20.7 to 80.1, showing the mixed inhibition.
11.
1995.06 서비스 종료(열람 제한)
Thiobacillus neapolitanus R-10 isolated from sludge of night soil, showed an oxidizing activity on several malodorous sulfur compounds. The microbe successfully utilized hydrogen sulfide(H_2S), methy mercaptan(MM), dimethyl sulfide(DMS) and dimethyldisulfide(DMDS) during the batch culture reaction, of which H_2S was rather rapidly oxidized. To examine the ability for removal of malodorous sulfur compounds, various concentrations of sulfide substrates were supplemented separately to basal medium and their responses were investigated. As the concentration of sulfide was increased, growth was accelerated within three days of cultivation. 2.5mM was the most favorable substrate concentration of sulfide added for all cases tested. However, when the concentration of sulfur compounds were raised over 4mM, they behaved as a growth inhibitor.
12.
1995.06 서비스 종료(열람 제한)
New two macrocyclic compounds using as carriers of liquid emulsion menbrame, have been synthesized. These reuslts provide evidance for the usefulness of the theory in designing the systems. The efficiency of selective transport for heavy metal ions have been discussed from the membrane systems that make use of SCN^- I^- , CN^- and Cl^- ion as co-anions in source phase and make use of S_2O_3^2- and P_2O_7^4- ion as receiving phase, respectively. The transport, rate of M(Ⅱ) was highest when a maximum amount of the M(Ⅱ) in the source phase was present as Cd(SCN)_2([SCN^-]=0.40M, Hg(SCN)_2([SCN^-]=0.40M) and Pb(CN)_2([CN^-]=0.40M). The Cd(Ⅱ) and Pb(Ⅱ) over each competitive cations were well transprted with 0.3M-S_2O_3^2- and 0.3M-P20_7^4 , respectively in the receiving phase. Results of this study indicate that two criteria must be met in order to have effective macrocycle-mediated transport in these emulsion system. First one must effective extraction of the M^n+ into the toluene systems. The effectiveness of this extraction is the greatest if logK for M^n+-macrocycle interaction is large and if the macrocycle is very insoluble in the aqueous phase. Second, the ratio of the logK values for M^n+-receiving phase (S_2O_3^2- or P_2O_7^4-) to M^n+-macrocycle (L_1 or L_2) interaction must be large enough to ensure quantitative stripping of M^n+(Cd^2+, Hg^2+ or Pb^2+) at the toluene receiving phase interface. L_1(3.5-benzo-10,13,18,21-tetraoxa-1,7,diazabicyclo(8,5,5) eicosan) forms a stable Cd^2+ and Pb^2+ complexes and L_1 is very insoluble in water and its Cd2^+ and Pb^2+ complex is considerably less stable than Cd^2+-(S_2O_3)_2^2- and Pb^2+-P_2O_7^4- complexe is On the other hand, the stability of the Hg^2+-L_1 complex exceed that of the Hg^2+-(S_2O_3)_2^2- and Hg^2+-P_2O_7^4- , and the distribution coefficient of L_2(5,8,15,18,23,26-hexaoxa-1,12- diazabicyclo-(10,8,8) octacosane) is much smaller than that of L_1. Therefore, the partitioning of L_2 is favored by the aqueous receiving phase, and little heavy metal ions transport is seen despite the large logK for Hg^2+-L_1 and M^n+(Cd^2+, Pb^2+ and Hg^2+)-L_2 interactions.
14.
1995.06 서비스 종료(열람 제한)
Generally, It is introduced to well-known other models without considering tidal current of the field. The paper presents field measurements and numerical model solving velocity field of Cheonsu Bay by two-dimensional tidal model. It was proved that this scheme is easy to handle complex topography. Computed results is represented characteristics of tidal current for Cheonsu Bay. The results of the study can be summarized as follows ; 1. Tide form number has 0.21 value. Tidal range estimated 630.3 ㎝ on spring, 454.1 ㎝ on mean and 277.9 ㎝ on neap, respectively. 2. Tidal current has semi-diurnal form. Distance of traveling observed 16.6 ㎞ on flood and 15.5 ㎞ on ebb. 3. Tidal velocity showed reversing current. It was found that tidal velocity above 100 ㎝/sec is about 20 %. 4. Computed results are in good agreement with the observed data. Applying the algorithm to Cheonssu Bay, velocity fields and dry bank phenomena are simulated well in spite of complex topography. 5. An advanced study on the effects of open boundary conditions should be continuously performed.