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
제5권 제2호 (1996년 4월) 14건
1.
1996.04
서비스 종료(열람 제한)
Observational date is integral in our understanding of present climate, its natural variability and any change due to anthropogenic effects. This study incorporates a brief overview of sampling requirements using data from the first ISLSCP Field Experiment (FIFE) in 1987 which was a multidisciplinary field experiment over a 15 km grid in Konza Prairie, USA. Sampling strategies were designed for precipitation and soil moisture measurements and also detecting land cover type. It was concludes that up to 8 raingages would be needed for valuable precipitation measurements covering the whole FIFE catchment, but only one soil moisture station. Results show that as new gages or station are added to the catchment then the sampling error is reduced, but the improvement in error performance is less as the number of gages or stations increases. Sampling from remotely sensed instruments shows different results. It can be seen that the sampling error at larger resolution sizes are small due to competing error contribution from both commission and omission error.
2.
1996.04
서비스 종료(열람 제한)
Diurnal variations of air quality for each season over Taegu city were analyzed using the characteristic features of the various synoptic wind fields. The air quality data which were monitored by four stations are the hourly averaged sulfur dioxid(SO_2), total suspended particulate (TSP) and oxidants (O_3) during the period of 1989 to 1992.
The various synoptic wind fields obtained from the 850 hPa geopotential height were divided into four geostrophic wind directions and two geostrophic wind speeds for each seasons. The synoptic weather conditions were again subdivided into two categories using the total cloud amounts.
The results shows that diurnal and seasonal variations of the air quality over Taegu city, such as sulfur dioxide, total suspended particulate and oxidants reveal the various characteristics under the same synoptic weather conditions.
3.
1996.04
서비스 종료(열람 제한)
Analysis of hourly variations of sulfur dioxide (SO2) concentrations affected by regional climates for the period of yellow sandy dusts was carried out from March 31 through April 9, 1993.
The concentration of SO2 at a coastal city, Kangnung city, was much higher than that at an inland city Wonju in the west, but the hourly distributions of SO2 concentrations show a similar tendency at both cities. Under the prevailing synoptic-scale westerly winds blowing over a high Mt. Taegualyang in the west toward Kangnung city in the eastern coastal region, the SO2 at Kangnung is trapped by an easterly sea-breeze during the day and under prevailing easterly winds, it is also isolated by the high wall of Mt. Taegualyang, with its high concentration from 14 to 16 LST.
Furthermore, when the westerly winds were dominent all day long, the high SO2 concentrations at Kangnung were produced by its intrusion from a urban city, Wonju or China in the west into a mountainous coastal city, Kangnung, to some extent, and when the air becomes rapidly cooled down at the clear daytime or the nighttime, their concentrations are also increased by a great amount of heating fuel combustion.
Especilly, its maximum concentrations were shown in Wonju and Kangnung from 08 LST through 10 LST, due to the increase of auto vehicles near the beginning time of office hour and were detected again after sunset due to both increases of vehicles at the end of office hour and heating fuel combustion.
During the period of Yellow Sandy Dusts which are transported from China into Korea, the SO2 concentrations on rainy days at Wonju and Kangnung were much lower than the monthly mean values of SO2, and their low concentrations could be caused by the scavenging process of rain.
4.
1996.04
서비스 종료(열람 제한)
This study is an attempt to investigate the chemical components of precipitation and its variation according to surface wind. Precipitation samples were collected by an wet-only precipitation sampler during the period of October 1994 to September 1995 at Kyungsan in Korea. The results obtained in this study are summerized as follows.
The annual average of precipitation pH is 5.0, the highest month of pH is July of 5.5, and the lowest month of pH is December of 4.4. The most frequent appearance is in the range of pH 5.0 to 5.5 and its rate is 56.8%. The order of ion concentration in precipitation is SO4^2->NO3^->Cl^-in case of anion and Ca^2+>NH4^+ >Na^+>Mg^2+ in case of cation. It is found from our analysis that the correlation coefficient among the precipitation pH and ion components is below r=0.3, while the correlation coefficient between SO4^2- and NO3, Na^+ and Cl^- is above r=0.8, respectively.
The mean pH of precipitation is 4.8 under the westerly wind and 5.2 under the easterly wind. The concentrations of anion and cation under the westerly wind are more than the concentrations under the easterly wind. In autumn, the concentration of Na^+ and Cl^- under the easterly wind are higher than the concentration under the westerly wind. The correlation coefficients between wind speed and pH, ion components show very low correlation of -0.41≤r≤0.2. But the present study show that the correlation coefficient between wind speed and pH of precipitation is positive and the correlation coefficients between wind speed and ion concentration is negative.
5.
1996.04
서비스 종료(열람 제한)
Photosynthetic pigments and their degradation products in suspended and sinking particles collected from the Gulf of Mexico waters 1987∼88, were measured using High Performance Liquid Chromatography (HPLC). The short term variations in flux rates of chlorophylls and carotenoids as well as their degradation products were compared at the mesoscale cyclonic and anticyclonic circulation features (cold core ring and warm core ring). Chlorophyll a was the predominant porphyrin of suspended particulate matter at both CCR and WCR. Among carotenoid pigments, 19`-hexanoyloxyfucoxanthin, which is a biomarker of prymnesiophytes, was dominant pigment at both rings. Phaeophorbide a, which is produced through the grazing processes of grazers, was the predominant degraded pigment in sinking particles at the study area. Total pigment flux in CCR was an order of magnitude higher than that in WCR. Less than 1% of the standing stock of the pigments measured sank out of the upper 200 m of the WCR on any given day. Thus, suspended particulate matter in Gulf of Mexico was not recycled rapidly.
6.
1996.04
서비스 종료(열람 제한)
This experiment was performed with the purpose of finding out the effect of simulated acid rain at various pH levels on the morphology and enzyme of Perilla frutescens var. japonica Hara. The pH levels of simulated acid rain ranged from pH 2.0 to pH 6.0. The experiment showed the anion concentrations in the order of SO4^-2, Cl^-, NO3, and F^-. SO4^-2 was found out to be the main factor which contributed to the rainwater acidification. A general decrease of growth in Perilla frutescens var. japonica Hara growth was shown with the decreas of pH concentration. As acidity increases, a definite reduction in the rates of germination, heigth of plant, malate dehydrogenase, and 6-phosphogluconate dehydrogenase was ovserved, but the density of spots on the leaf apex was increased.
7.
1996.04
서비스 종료(열람 제한)
This study was conducted to investigate the effects of environmental factors such as temperature, salinity, pH, and UV light on the survival of life-threatening Vibrio vulnificus. In the temperature range of 15 to 25℃, the numbers of V. vulnificus increased during the 6-day incubation, but outside this range, the survival of V. vulnificus was poor. Incubation between 1 and 10℃ showed that V. vulnificus survived poorly below 10℃. At salinities between 5 and 25ppt, the numbers of V. vulnificus increased or remained unchanged for 6-day. At salinities above this range, the numbers of V. vulnificus decreased. The optimal pH range was 6.5 to 8.0 and outside this range, the survival ratio of V. vulnificus was small. At 15 and 25℃, UV radiation was bactericidal for cultures of V. vulnificus. The counts of V. vulnificus were reduced approximately 10,000-fold after 2h of UV light treatment at both temperatures. Above results showed that environmental factors were effective on the survival of V. vulnificus in the environment.
8.
1996.04
서비스 종료(열람 제한)
The present study was performed to elucidate the distribution of protozoans according to the actual conditions of soil pollution around Ulsan industrial complexes, Korea. Samples were collected from the top-soils of 13 localities in eight times during the period from 16 April 1994 to 14 January 1995. As a result of this study, total 11 species of hypotrichous ciliated protozoa were identified and analyzed. These hypotrichs are 6 species of stichotrichine hyporichs (Keronopsis sp., Pseudourostyla sp., Holosticha sylvatica, Holosticha multistylata, Holosticha sp. and Paruroleptus sp.) and 5 species of sporadotrichine hypotrichs (Oxytricha sp., Steinia sp., Histriculus cavicola, Hemisincirra sp. and Gonostomum of affine). Of these 11 species, 4 species (Keronopsis sp., Pseudourostyla sp., Holosticha sp. and Hemisincirra sp.) are reported for the first time from Korea. All the sampling localities could be grouped in three zones by the cluster analysis with the abundance and distribution of protozoans. This result is approximately coincide with the zonation by the concentration of heavy metals.
9.
1996.04
서비스 종료(열람 제한)
This study was conducted for the efficient utilization of a scoria, which is abundantly found in Cheju island, as adsorbent and the scoria was examined for its performance in clarification of adsorption of heavy metal ions.
The order in heavy metal ions adsorbed on scoria was; Pb^+>Cd^2+>Cu^2+>Ag^+>Co^2+>Zn^2+>Cr^3+>Cr^6+. This tendency was relatively consistent with the decreasing order of radius of hydrated metal ion. Also, the smaller scoria size and the larger amounts of scoria showed higher removal efficiency for heavy metal ions. The same scoria size showed more effective removal efficiency for heavy metal ions at lower initial concentration than at higher initial concentration. The adsorption abilities of original scoria and chemically treated scoria were compared.
Adsorption isotherm of scoria was generally obeyed to Freundlich formula than Langmuir formula and Freundlich constant, 1/n was obtained in the range of 0.2∼0.4.
10.
1996.04
서비스 종료(열람 제한)
To improve coagulation characteristics and to reduce dossage of chemicals in watertreatment, polyaluminium sulfate was manufactured by reaction of polymerization between aluminium sulfate and sodium aluminate. As the results of affirmation and performance test, the yield of product was about 24% from molecular cut off levels by ultrafilteration method. The type of molecular is nearly affirmated as a kind of complex like Alm. (OH)n^(3m-n)+ from Scanning Electr Electron Mipy(S.E.M.) and X-ray diffraction test. Since the synthesized polymer was supposed to be quasi, further study for stabilization was required.
11.
1996.04
서비스 종료(열람 제한)
New thia-and diselena-crown ethers containing two suffer and selenium donor atoms have been prepared. And then, mercury (Hg^2+) ion-selective electrodes with PVC-plasticizer (STPB) based on some macrocycles as neutral carriers were also made. The electrochemical selectivities for various ions, and the effects for macrocycles, matrix of membranes, ratio of plasticizer to macrocycles, concentration and pH of test solution were investigated on the Hg^2+ ion selective electrodes. The 1,10-diselena-l8-crown-6-PVC-STPB (sodium tetraphenylborate) exhibited good linear responses of 28.2 ± 0.6 decade^-1 for Hg^2+ ion in the concentration ranges of 10^-2∼10^-6 M Hg^2+ ion. This electrode exhibited comparatively good selectivities for Hg^2+ ion in comparison with alkali and alkaline earth metal ions, some heavy metal ions and rare earth metal ion in the range of pH 2.5∼6.0. In addition, this electrode was applied as a sensor in the titration of Hg^2+ ion with I^- ion in water.
12.
1996.04
서비스 종료(열람 제한)
The objectives of this study are to examine combustion characteristics of E.V.A. and rubber wastes by fixed-bed incinerator. The results are as follows. Combustion temperature with time rises rapidly, and mass of E.V.A. reduces at short time in E.V.A. combustion. In variation of air-fuel ratio (m), the ideal values of m of E.V.A. and rubber are 2.5, 1.5 respectively. Mixed-waste combustion is more economic than single E.V.A. combustion, because we can get high combustion efficiency (94.0∼99.0%) at 2.0 air-fuel ratio of mixed-waste combustion. Removal efficiencies of SO2 at cooling tower are about 20%. The combustion efficiencies of rubber are over 98.0% according to the experimental conditions.
13.
1996.04
서비스 종료(열람 제한)
This study was performed to find the most desirable emission reduction for each mobile source pollutant and the optimal control strategy at a given level of expenditures in Pusan City in 2000 by using the interactive ε-constraint method developed by Chang-Hyo Lee and Hyung-Wook Kim, which is one of the mathematical programming models.
The most desirable emission reduction is 7093 ton/year for particulate (TSP), 4871 ton/year for NOx, 5148 ton/year for HC and 36779 ton/year for CO. The optimal control strategy is as follows;
1. As to passenger car and taxi limiting VKT (vehicle kilometers travelled) in congested areas will be necessary. In addition to this, improving vehicle inspection program should be enforced.
2. As to small-gasoline bus, traffic adaptive control system will be necessary.
3. As to small-diesel bus, non-adjustable engine parameters will have to be applied.
4. As to heavy bus and heavy truck, catalytic trap oxidizer and limiting VKT in congested areas will be necessary.
5. As to motorcycle, 2-cycle motorcycles should be converted to 4-cycle motorcycles.
14.
1996.04
서비스 종료(열람 제한)
In order to investigate the effects of pH and organic matter content on cadmium adsorption and exchangeable cations desorption in soils, the adsorption isotherms of cadmium and the desorption isotherms of calcium and magnesium on four New Jersey soils at four pH values were plotted, and the cadmium partition coefficients (Kd) were also calculated. The slopes of cadmium adsorption isotherms dramatically increased with increasing solution pH. Judging from Langmuir adsorption equations, the maximum adsorption quantities (b) of cadmium at high pH values were much greater than those at low pH values for the same soil. The partition coefficients increased greatly with increasing solution pH. The slopes of regression equations between partition coefficients and pH values were steep in the order of the organic matter content of the soils. The correlation coefficients (r^2) between partition coefficient and organic matter content for 1 × 10 exp (-4) M increased from 0.3027 at pH 4.0 to 0.9964 at pH 8.5 and from 0.2093 at pH 4.0 to 0.9657 at pH 8.5 for 2×10 exp(-4) M Cd (NO3)2. The desorption quantities of calcium and magnesium decreased with increasing solution pH and increased with increasing cadmium adsorption.
