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
제7권 제1호 (1998년 2월) 17건
1.
1998.02
서비스 종료(열람 제한)
This paper aims to estimate the change point of the precipitation in Pusan area using the several statistical approaches. The data concerning rainfall are extracted from the annual climatological report and monthly weather report issued by the Korean Meteorological Administration.
The average annual precipitation at Pusan is 1471.6 ㎜, with a standard deviation of 406.0 ㎜, less than the normal(1486.0 ㎜). The trend of the annual precipitation is continuously decreasing after 1991 as a change point. And the statistical tests such as t-test and Wilcoxon rank sum test reveals that the average annual precipitation of after 1991 is less than that of before 1991 at 10% significance level. And the mean annual precipitation in Kyongnam districts is also continuously decreasing after 1991 same as Pusan.
2.
1998.02
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The dicriminant function was introduced to understand the cause and establish the prediction method of red tides occurring in Jinhae Bay, Korea. Two sea regions of Masan and Haengam Bays and Dangdong and Wonmun Bays had different types of causes and patterns for red tides. In Masan and Haengam Bays, the red tides concentrically occurred during June and September. For example, in June the red tides occurred from physical and meteorological factors, which are related to the stratification and the increase in planktons. However, in August the red tides occurred from the water quality environment, based on these conditoins. Futhermore, in September the red tides were caused by the balance between the meteorological and water quality environmental factors. In contrast to those, in Dangdong and Wonmun Bays, the red tides mainly occurred during July and October and the frequency of occurrence was not as much as Masan and Haengam Bays. Especially, in August and September most meteorological and physical factors or water quality environmental factors appeared to contribute to the occurrence of red tides. This indicates that red tides do not easily occur as they are controlled by various environmental factors particularly in these regions.
The discriminant functions were applied to predict red tides which they were actually occurred in Masan and Haengam Bays in June. The results showed that they were successful for the prediction of red tide at Haengam Bay but not at Masan Bay. The reason for their discrepancy in Masan Bay could have come from using a slight higher value of pH or COD in May, instead of its value in June.
3.
1998.02
서비스 종료(열람 제한)
In establishing artificial fences in a certain locality, type of its area or wind blown against them from the front side is primarily considered. Researchers on fences also concentrate on upstream, wind blown against them from the front side in 90° angle.
In this research, simulations were carried out on the direction of wind changed by each season, and regardless of seasonal wind, on the fences effect of wind direction on fences, through an atmospheric boundary layer wind tunnel.
When I compared the velocity distribution of upstream against the fences in 90° angle with that of 75°, 60°, and 45˚ respectively, the velocity distribution at downstream of the latter cases generally surpassed that of the former one.
4.
1998.02
서비스 종료(열람 제한)
The present study intends to investigate the transient response of an atmosphere/ocean general circulation model to a gradual increase of atmospheric carbon dioxide. To detect the climatic change of the surface air temperature due to gradual increasing carbon dioxide for 100 years, two runs of GFDL CGCM for 1 % CO_2 run with increasing CO_2 and the control run with fixed CO_2 are compared.
From results it is noted that the transient response of surface air temperature is more increased over the Northern Hemisphere than the Southern Hemisphere. However, in Northern Hemisphere the transient response of the surface air temperature due to the gradual increase of atmospheric carbon dioxide is slowly increased with latitudes and is clearly larger over continents than oceans. The annual global mean temperature is continuously increased with 0.03552 per one year with strong S/N ratio and distinguished from the natural variability. The time dependent response of the gradual increasing CO_2 has the strong seasonal variability with small change in summer and large change in winter, and the strong regionality in the Asian and the American continents. It has been suggested that the direct and the feedback processes in the climate systems should be investigated by the detailed sensitivity runs to get the meaningful estimate of the CO_2 forced variability.
5.
1998.02
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This study was carried out to investigate the collection Efficiency of mass in collector step at the different of physical gas characterization. This work has focused on the dependence of the collection efficiency of mass in the collector zone of a two-stage set up field with gas temperature T and the dew point tmeperature. To identify the dependence of the mass collection efficiency on the grounded plate of the collector zone M_P,k by the specific electric resistance of dust ρe and the relative humidity φ, 20 attempts have been made with three different gas temperature (50℃, 80℃, 110℃) at different dew point. At the specific electric resistance of dust ρe=10^6Ωm which relative humidity corresponds to φ> 15%, a easy rise of the grounded plate secluded dust mass share was measured again. As the result of the higher cohesion imprisonment power due to the adsorbtion of particle, the rise of the relative humidity developed on the particle surface. Therefore, the collection efficiency of mass was not predominant the high temperature T in the collector zone, neither was the pecific ellectric resistance of dust dependent.
6.
1998.02
서비스 종료(열람 제한)
The feasibility of foam separation to remove protein in aquacultural recirculating water was investigated. From the results of batch foam separation on protein removal, superficial air velocity and initial protein concentration in bulk solution were found to be important operational factors in determining removal rates of protein. The protein removal rate by batch foam separation was proportionally increased with the superficial air velocity.
Performance characteristics of continous foam separator were highly dependent upon the operating parameters of superficial air velocity, hydraulic retention time(HR) and foam height. Removal efficiency of protein increases with increasing superficial air velocity and HRT, and independent on foam height. As DO concentration was increased with superficial air velocity, foam separator is also used for oxygen addition. It could be confirmed that foam separator might offer better perspective for protein removal in aquacultural recirculating water
7.
1998.02
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The effects of aloe on the MDA(malondialdehyde) and the blood biochemical components of heavy metal poisoning in SD rat were examined and the following results were obtained. In rat liver homogenate intoxicated with CdCl_2, lipidperoxide was increased each 2.37times(24h), 3.31times(72h) but lipidperoxide in aloe administration groups was lower each 47%, 64% than in heavy metal group. In rat kidney homogenate intoxicated with CdCl_2, lipidperoxide was increased 1.85times(24h), 1.33times(72h) but lipidperoxide in aloe administration groups was almost the same as that of normal group. Lipidperoxide of kidney homogenate was slightly decreased as time passed. Also heavy metal poisoning rats showed high levels(1.38-2.50times) of serum AST, ALT and BUN. However, the administration of aloe significantly inhibited the reduction of them. These results suggest that Cd-induced hepatic and renal injury, via increase lipidperoxide and release of AST, ALT and BUN. Aloe may be used to inhibit or prevent the hepatic and renal toxicity which results from the heavy metal.
8.
1998.02
서비스 종료(열람 제한)
The effects of organophosphorus and carbamate pesticides were examined inhibition of the acetylcholinesterase activity in the chicken brain with enzyme - inhibition methods. The acetylcholinesterase activity in chicken brain determined by the Ellman method was 167 μmol/min/g protein. The optimum pH of acetycholinesterase was 8.2. pI_50 of acetycholinesterase by some organophosphorus were 3.80M of phosphorodithioate, 4.04M of phosphorothioate, 6.33M of phosphate, and 6.60M of phosphrothiolate. pI_50 of acetycholinesterase by some carbamates were 5.10M of XMC, 5. 90M of carbofuran, 6.16M of isoprocarb, 6.30M of carbaryl, 6.47M of BPMC, and 6.77M of propoxur. pI_50 of carbamates selected was similar to that of phosphorothioate and phosphate organophosphates
9.
1998.02
서비스 종료(열람 제한)
The biosorption of heavy metals has received a lot of attraction for application of metal ions treatment. In this work, we studied with Arthrobactor sp., screening from a wastewater containing heavy metals. The Pb uptake capacity of Arthrobactor sp. was nearly 146.9 ㎎ Pb/g dry biomass(initial concentration, 500 ㎎/L), whereas the Pb uptake capacity of Saccharomyces cerevisiae and Saccharomyces uvarum were only around 39.40 and 35.65 ㎎ Pb/g dry biomass, respectively. The Pb and Cr were removed from metal solution much more efficiently than were the other metals(Cd and Cu). The Pb uptake capacity of Arthrobactor sp. increased with increasing in pH(1.8, 3.0 and 4.0) and decreased with increasing of biomass concentration. At pH 4.0, the Pb uptake capacity reached 244 ㎎ Pb/ g dry biomass in Pb initial concentration of 1000 ㎎/L. The Pb uptake capacity of Arthrobactor sp. treated by KOH and CaCl_2 were increased above values obtained with untreated Arthrobactor sp. However, the Pb uptake capacity of Arthrobactor sp. treated by NaOH was decreased. The removal efficiency of Pb was kept above 99% before the breakthrough points were reached.
10.
1998.02
서비스 종료(열람 제한)
Toxic Mastoparan B(MP-B) which is purified from the venom of the hornet Vespa basalis is a cationic amphiphilic tetradecapeptide. MP-B and its Ala-substituted analogues were synthesized by solid phase method and the toxic peptide-membrane interactions were examined by circular dichroism(CD) spectra, fluorescence spectra, and leakage abilities in phospholipid membranes. In the presence of phospholipid vesicles, synthetic MP-B and its analogues formed amphiphilic α-helical structures, but in the buffer solution, those exhibited random coil conformation as measured by CD. Fluorescence spectra of MP-13 and its analogues which indicated the binding affinity of peptide on phospholipid vesicles showed that the replacement of Lys at position 2 and 11 with Ala caused a remarkable effect in the blue shift and that at position 2, in the leakage ability of the peptide.
11.
1998.02
서비스 종료(열람 제한)
Surface heat budget of the Deukryang Bay from July 1, 1992 to September 12, 1993 is analyzed by using the meteorological data (by Changhung Observatory and Mokpo Meteorological Station) and oceanographical data (by Research Center for Ocean Industrial Development, Pukyong National University).
Each flux element at the sea surface which has annual variation is derived with application of an aerodynamical bulk method and empirical formulae. The solar radiation is the maximum in spring and summer, and the minimum in autumn and winter. The effective back radiation, the latent heat and the sensible heat are the maximum in autumn and winter, and minimum in summer.
The heat storage rate is calculated by using the rate of water temperature variation according to the depth. The oceanic transport heat is estimated as a residual. The net heat flux, the heat storage rate are positive in spring and summer, while they are negative in autumn and winter. The oceanic transport heat is convergence in winter and divergence in the rest of seasons.
12.
1998.02
서비스 종료(열람 제한)
Because permeate flux was very low as it has the suspension solid of high concentration in the ultrafiltration membrane separation treatment of dyestuff wastewater, pre-treatment of Fenton reaction was carried out. In the case of pH 3, COD removal rate was the highest of 58%. When PAC was added into the pre-treatment supernatant, the COD removal rate was found to be 53%, and when COD was 153㎎/L, the removal rate was 92.3% in the ultrafiltration separation. In addition, the effect of the addition of PAC on the permeate flux was also investigated. The decrease of permeate flux in the presence of PAC was higher than in the abscence of PAC, but the recovery of permeability by cleaning was better in the case of PAC system.
13.
1998.02
서비스 종료(열람 제한)
This study was conducted to assess the characteristics of pigment wastewater and the removal rates of appropriate treatment by physical, chemical and biological process, and the possibility of reuse for effluent.
Based on the results, the wastewater qualities of pigment were pH 5.1±3.4, temperature 43.0±5.0℃ BOD 1,431.4±589.6㎎/ℓ, COD 2,282.8±66.5㎎/ℓ, turbidity 1,340±82ONTU, color 243.0±147.Ounit, Pb 36.5±9.5㎎/ℓ and Cr^+6 10.3±1.3㎎/ℓ, respectively.
The removal rates of adsorption by activated carbon and filter process were BOD 40.6%, COD 57.0%, turbidity 89.6%, color 87.2%, Pb 86.0% and Cr^+6 10.6%, respectively. And the removal rates of reduction, neutralization, coagulation and air floatation process were BOD 18.2%, COD 24.3%, turbidity 74.3%, color 56.7%, Pb 68.6% and Cr^+6 97.8%, respectively.
The removal rates of activated sludge process were BOD 95.9%, COD 86.0%, turbidity 27.8%, color 25.2%, Pb 26.9% and Cr^+6 50.0%, respectively.
The total removal rates of treatment by physical, chemical and biological process were BOD 98.0%, COD 95.4%, turbidity 98.1%, color 95.8%, Pb 97.0% and Cr^+6 99.0%, respectively.
According to the test results for possibility of reuse with coagulation-adsorption by activated carbon process of effluent, COD was higher than that of raw water and others were similar to that of raw water, thus, it is considered to be reused.
14.
1998.02
서비스 종료(열람 제한)
Ion exchange performance to remove nitrate in water was studied using commercially available strong base anion exchange resin of Cl^- type in the batch and continuous column reactors. The performance was tested using the effluent concentration histories for continuous column or equilibrium concentrations for batch reactor as a function of time until resins were exhausted or reached ionic equilibrium between resin and solution. Anion exchange resin used in this study was more effective than activated carbon or zeolite for nitrate removal. With large resin amount or low initial concentration, nitrate removal characteristics for a typical gel-type resin was increased. On considering the relation between the breakthrough capacity and nitrate concentration of the influent, the use of anion exchange resin were suitable for the higher order water treatment. The nitrate removal of above 90% could be possible until the effluent of above 650 BV was passed to the column. Thus, the commercially available strong base anion exchange resin of Cl^- type used in this study could be effectively used as economic material for treatment of the groundwater. The breakthrough curves showed the sequence of resin selectivity as SO_4^2- > NO_3, > NO^2- > HCO_3^-. The results of this study could be scaled up and used as a design tool for the water purification system of the real groundwater and surface water treatment processes.
15.
1998.02
서비스 종료(열람 제한)
To study the optimum conditions of composting with industrial wastewater sludge, the variations of temperature and CO_2 generation amount during the composting periods were investigated. The conditions were that industrial wastewater added to bulking agents such as sawdust and rice hull was used, and differently treated with microorganism seeding or not, initial C/N ratios, air flow rate and initial moisture contents, respectively. The results were summarized as follows ;
Seeding 5% of microorganism was higher the temperature than not seeding. And using sawdust as bulking agents, and adjusting 30∼40 of initial C/N ratio, 200㎎/ℓ·min. of air flow rate and 67∼68% of initial moisture contents were higher the temperature than any other conditions.
Seeding 5% of microorganisms was higher CO_2 generation amount than not seeding. And that was much in the order of 7∼40, 30∼34 and 22∼23 of initial C/N ratio.
Judging from the results, it should be considered that the optimum conditions in the composting of industrial wastewater sludge were seeding of 5% microorganisms, and adjusting 30∼34 of initial C/N ratio, 200㎎/ℓ·min. of air flow rate and 67∼68% of initial moisture contents.
The contents of inorganic matters and C/N ratio during the composting periods at optimum condition were a little increased, and heavy metals contents after composting were lower than standard for fertilizer.
16.
1998.02
서비스 종료(열람 제한)
The Dongbok lake water before and after alum coagulation and activated carbon adsorption were analyzed in terms of organic contents, molecular weight distributuin (MWD), and UV-absorbance. Dissolved organic compounds in the Dongbok lake were fractionated into three molecular size classes by gel permeation chromatography. The fractionation was reasonably successful in isolating compounds with MW>10,000 (Fraction Ⅰ) and those with 3,000MW (Fraction Ⅲ. The bulk of the dissolved carbon was present in compounds of molecular weight in the range of 3,000∼10,000. Alum coagulation preferentially treated molecules of high molecular weight, which has molecules larger than 10,000. The dissolved organic carbon (DOC) removal after activated carbon adsorption was high in the Fraction Ⅱ, Ⅲ. The A_260/DOC ratio after alum and activated carbon treatment was high in the Fraction Ⅰ, Ⅱ. This results suggest that the organics remaining after each treatment has a trihalomethane formation potential
연구노트
17.
1998.02
서비스 종료(열람 제한)
During the spring and fall of 1994 and winter of 1995, the exposure time of periphyton biomass on the artificial substrata at 10 headwater streams in the southeastern Korea was evaluated in 7-14 day interval. In the streams with low periphyton biomass (chl a: 2-4 ㎎/㎡) in natural rocks, biomass of artificial substrata (unglazed the: 3.7 × 9.5 × 2 ㎝) exceeded that of the natural rocks after 28 days, while sites with high biomass (chl. a: 20-60 ㎎/㎡) in natural rocks showed slower biomass accumulation after 40 days. Due to the high light input and temperature in a partially shaded mountain stream, development of periphyton biomass in spring occurred faster than that of winter. In general, development of periphyton biomass placed on artificial substrata took 4-5 weeks in spring and at least 6 weeks in winter to reach the natural level.
