간행물
한국환경과학회지 KCI 등재 Journal of Environmental Science International
- 발행기관 한국환경과학회
- 자료유형 학술지
- 간기 월간
- ISSN 1225-4517 (Print)2287-3503 (Online)
- 수록기간 1992 ~ 2023
- 주제분류 자연과학 > 자연과학일반 자연과학 분류의 다른 간행물
- 십진분류KDC 539DDC 628
권호리스트/논문검색
제6권 제4호 (1997년 8월) 13건
1.
1997.08
서비스 종료(열람 제한)
Environmental problems emerged as common global problems awaiting solution. Active collaborative efforts are required of nations and communities in order to solve environmental problems effectively. International collaboration occurs much more commonly these days than before, and European Community(EC) mumber countries are no exceptions. EC has established and executed the five-year programs on Environmental Policy Implementation, which explicated basic principles for environmental policy development, since 1973. EC programs tend to emphasize that the direction of the policies should reflect a change from a remedial approach to a preventive approach. Those programs have brought an awareness of the importance of Environmental Impact Assessment(EIA) to EC member countries. France installed an EIA system in 1976, which was the first among member countries. Several other member countries also established a system. EC decided that a common guideline was necessary, and therefore formulated the "European Community Guideline for Environmental Impact Assessment" in 1985. All member countries were required to legislate an EIA system within three years, according to the Guideline. This study will conduct a comparative analysis of the current EIA systems of different EC member countries. The findings of this study will provide helpful information on how to improve the efficacy of the Korean system.
2.
1997.08
서비스 종료(열람 제한)
The characteristics of spring machanism in the Cheju Island were analyzed by statistical techniques. Basic characteristics, areal and altitudinal variations, and correlations of spring data were ivestigated. In this study, however, the subjects of the study are the 451 springs, the whole basin of Cheju Island devided into four groups. In this study, analyzed the spring phenomena on the basis of both the geologic elements and the topographic elements.
Also, the spring zone in Cheju Island are classified into three types that the mountain area, the middle area, the coastal area in spring distribution by altitude. The quentity of spring and variability show subvariety on the average according to Meinzer`s classification and the whole basin of spring shows various distributions from Third to Sixth. The results of this study can be utilized to evaluate the condition of groundwater development in Cheju Island.
3.
1997.08
서비스 종료(열람 제한)
In order to study the seasonal variation of kinetic and potential energy of residual flow field in Suyoung Bay of Korea, we calculated its energy budget and compared it with the tidal energy there. The potential energy shows the large value in winter and spring and the small one in summer and early autumn when the density stratification is developed. The kinetic energy of residual flow varies seasonally and the seasonally averaged kinetic energy of residual flow per unit area is 6.4 × 10_-4 ergs s^-1cm^-2. It is mainly governed by the density-driven current with the exception of that in November when the kinetic energy of tide-induced residual current is larger than those of density-driven current and winddriven current. An averaged fraction of the kinetic energy of tide-induced residual current, wind-driven current and density-driven current, which are the major components of residual flow, is 29.1%, 3.4%, 67.5%, respectively, to the kinetic energy of residual flow. The fraction of kinetic energy of residual flow, potential energy and tidal energy per unit area is 1.0 : 6.7 × 10_3 : 8.2 × 10_4, respectively.
4.
1997.08
서비스 종료(열람 제한)
An objective method for the generation of velocity streamfunction is presented for dealing with discretely sampled oceanic data. The method treats a Poisson equation (forced by vorticity) derived from Helmholtz theorem in which streamfunction is obtained by isolating the non-divergent part of the two-dimensional flow field. With a mixed boundary condition and vorticity field estimated from observed field, the method is implemented over the Texas-Louisiana shelf based on the current meter data of the Texas-Louisiana Shelf Circulation and Transport Processes Study (LATEX) measured at 31 moorings for 32 months (April 1992 - November 1994). The resulting streamfunction pattern is quite consistent with observations. The streamfunction field by this method presents an opportunity to initialize and to verify computer models for local forecasts of environmental flow conditions for oil spill, nutrient and plankton transports as well as opportunity to understand shelf-wide low-frequency currents.
5.
1997.08
서비스 종료(열람 제한)
Numerical Simulation of Ozone Concentration using the Local Wind Model in Pusan Coastal Area , Korea
Numerical simulations of photochemical air pollution (CBM: Carbon-Bond Mechanism) under a theoretical three-dimensional local wind system are carried to clarify the fundamental characteristics of the effects of local wind on photochemical air pollution.
According to the AWS data of Pusan coastal area and KMA, the surface wind of Pusan during summertime showed a very remarkable land and sea breeze circulation. The ozone concentration distribution using local wind model showed that high ozone concentration zone near coastal area moved toward inland in the afternoon. This change implies a sea breeze increases the ozone concentration, but a land breeze decreases it in Pusan coastal area
6.
1997.08
서비스 종료(열람 제한)
In the Atmosphere under the various physical and chemical condition different chemical reactions occur and there are a number of air pollutants which are generated by photochemical reaction by absorbing solar energy. Therefor various testing simulation was done as foundation work to develop the numerical model for the prediction of concentration of air pollutants. It was shown change of major air pollutants concentration in according to variation of photodissociation speed constant, K_1 and initial condition of air pollutants concentration which plays major role in photochemical reaction.
The photochemical reaction model which was used in this study is found to be useful for understanding relationship among the concentration of reacting air pollutants and the prediction of concentration of air pollutants in urban atmosphere
7.
1997.08
서비스 종료(열람 제한)
The Characteristics of atmospheric flow and dispersion of air pollutants in the mountainous coastal area were studied using three-dimensional model by the combination of land/sea breezes and transport. It was then applied to Pusan city. As the urban area considered in this study is located in a mountainous coastal area, the atmospheric flow is strongly affected by the land/sea breezes and mountain/valley winds. The typical effects of land/sea breezes on the dispersion and the characteristics of pollutants movement in the region were analysed. The model has been proved to be an useful tool to pridict real time air pollutants transport as shown by the results of application studies in Pusan, Korea which is an urbanized coastal area with mountainous topography.
It was found that the pollutants are differently transported and concentrated as going inland by the influence of the sea breeze with topographic changes. By comparing the pollutants concentrations of the simulated results with those of the observational results, it is shown that simulated results in this study are in qualitative agreement with observational ones.
8.
1997.08
서비스 종료(열람 제한)
The effects of various intensity of UV-B on barley seedling were investigated by PS I and Ⅱ activities and chlorophyll fluorescence. The inhibitory effect of UV-B radiation on electron transport activity was increased as the intensity of UV-B irradiation was increased. Especially, PS Ⅱ is more sensitive to UV-B radiation than PS I is. By the addition of artificial electron donor, DPC, to the chloroplasts of the barley seedlings treated with UV-B, the photoreduction of DCPIP was recovered by only 11% on electron transport activity. However, the activity of PS Ⅱ was inhibited by 45% by the treatment with UV-B, but recovered it only 11% by the addition of DPC. These suggest that other sites besides the oxidation site of PS Ⅱ may be affected more by UV-B irradiation. As the intensity of UV-B was increased, Fo was increased while Fv was decreased, and thus Fv/Fm was decreased. This means that photochemical efficiency was reduced. With this parameters, it might be that UV-B radiation affected adversely to around PS Ⅱ.
9.
1997.08
서비스 종료(열람 제한)
The biodegradable characteristics of poly-β-hydroxybutyrate(PHB) film by fungi and soil burial are investigated. As the results of the American Standards for Testing and Materials(ASTM) method, the growth of Aspergillus niger was apparent on the PHB containing plate. This suggests that PHB was utilized as the sole carbon source by Aspergillus niger and ASTM method may have applications as measuring means of biodegradability of polyhydroxyalkanoic acid(PHA). PHB film was studied by monitoring the time-dependant changes in weight loss of PHB film under 30℃ and relative humidity 80 % during pot-test. As the results of pot-test, PHB film was decomposed about 87 % in 30 days by soil microorganisms. PHB film was more slowly degraded than PHB/HV film.
10.
1997.08
서비스 종료(열람 제한)
Pesticide residues were extracted with 70% acetone and transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil and alumina-N. The final extract was analyzed by gas chromatography with electron-capture detector(GC/ECD) and nitrogen-phosphorus detector(GC/NPD). Recoveries of the 17 organochlorine pesticides were ranged from 60.8 to 84.9% and those of 15 organophosphate pesticides, from 70.5% to 100.0%(except phosmet and azinphos-methyl). The minimum detectable levels of this analytical method were low(0.021-0.058㎎/㎏).
11.
1997.08
서비스 종료(열람 제한)
The study was carried out to demonstrate the superiority of used packing in view of energy saving and efficiency of mass transfer, comparing with conventional packing.
The results are as follows
1. Owing to low pressure drop under high load, 25㎜ NSW-ring, pp. can cause energy saving
2. The unique magnitudes of used packing are as follows
C_o=5.78, m = 0.67, n = 0.46
3. Used packing can make high efficiency including energy saving because of low pressure drop per the number of transfer unit.
To rate the characteristic of packing, it should be carried out that the measurement of pressure drop per packing height and per the number of transfer unit. This study demonstrated the superiority of used packing by earring out above experiment and could be used as basic reference for design and predicting efficiency of packing tower which is filled with same packing.
12.
1997.08
서비스 종료(열람 제한)
The pyrolysis reactions of atomic hydrogen with chloroform were studied in a 4 cm i.d, tubular flow reactor with low flow velocity (518 ㎝/sec) and a 2.6 ㎝ i.d. tubular flow reactor with high flow velocity (1227 ㎝/sec). The hydrogen atom concentration was measured by chemiluminescence titration with nitrogen dioxide, and the chloroform concentrations were determined using a gas chromatography. The chloroform conversion efficiency depended on both the chloroform flow rate and linear flow velocity, but did not depend on the flow rate of hydrogen atom.
A computer model was employed to estimate a rate constant for the initial reaction of atomic hydrogen with chloroform. The model consisted of a scheme for chloroform-hydrogen atom reaction, Runge-Kutta 4th-order method for integration of first-order differential equations describing the time dependence of the concentrations of various chemical species, and Rosenbrock method for optimization to match model and experimental results. The scheme for chloroform-hydrogen atom reaction included 22 elementary reactions. The rate constant estimated using the data obtained from the 2.6 cm i.d. reactor was to be 8.1 × 10 exp (-14) ㎤/molecule-sec and 3.8 × 10 exp (-15) ㎤/molecule-sec, and the deviations of computer model from experimental results were 9% and 12%, for the each reaction time of 0.028 sec and 0.072 sec, respectively.
13.
1997.08
서비스 종료(열람 제한)
In order to investigate the possibility as a simple technique of wastewater treatment for recirculating aquaculture system, the experiment by a biofilter unit was carried out. The high and stable removal efficiency of nitrogen could be obtained by selecting the optimum recycle ratio and DO concentration. It was found that the proper combination of nitrification and denitrification step in the reactor would be required for increasing the removal efficiency. The extent of nitrogen removal gradually decreased with the rise of recycle ratio since the depression of denitrification by the lack of hydrogen donor. The depression of nitrogen removal was overcome by increasing the C/N ratio in the wastewater.
The extent of phosphorus removal was increased slightly with the increase of DO concentration and recycle ratio, but high removal efficiency was not observed. However, the extent of COD removal was not affected by recycle ratio and DO concentration and showed the stable removal of above 90%.
