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        검색결과 6

        1.
        1996.10 KCI 등재 서비스 종료(열람 제한)
        A method for the simultaneous analysis of 31 residual organic chloride pesticides was studied using gas chromatography. Prepared analytical samples were injected to gas chromatography (HP 5890 Series II plus) on the Ultra-2 column with ECD. The packing materials for column were changed as the following reagents ; florisil and alumina N. The residual solution was loaded to column and was eluted with elution solvents ; ether : benzene (2 : 8) solution, hexane : benzene (1:1) solution, dichloromethane, acetone, and methanol. The analytical results showed that 6 kinds of organic chlorides were not detected when florisil (first condition) was used as the column packing material. The nondetected 6 kinds of organic chlorides in the first analytical condition were detected and the recoveries of thrin-pesticides were increased, in particular, captan and captafol, but the recoveries of benzene hexachloride compounds were decreased when dichloromethane and methanol were added as elution solvents (packing material was florisil as in the first condition). The recoveries of dichlorfluanid, chlorofenvinfos, folpet, and dicofol were increased and that of aldrin was increased, but those of captan and captafol were not good when alumina N was used as the packing material. To detect simultaneously thrin-pesticides, captan, and captafol, florisil and alumina N were used as the packing materials. The elution result showed that captan and captafol were not detected. This was because the column was activated insufficiently. The analytical method was the best (31 kinds of organic chlorides in the residual pesticides were detected sharply and showed high sensitivity) when the column (packing materials were florisil and alumina N, together) was fully activated and the impurities were removed using various elution solvents.
        2.
        1996.10 KCI 등재 서비스 종료(열람 제한)
        The toxic substances (endotoxins) from the bacterial cell walls were extracted by using incubator, centrifuge, UV-Vis spectrophotometer, and their fatty acid compositions were analyze by Gas Chromatography. The lethal toxicities and pyrogenic activities of toxic substances were tested and the results were compared each other. The results of fatty acid analyses showed that the major fatty acid of the toxic substance was tetradecanoic acid for Vibrio vulnificus, dodecanoic acid for Escherichia coli and decanoic acid for Salmonella typhimurium. These three fatty acids were the main fatty acids for three toxic substances (more than 70%). The unique points in the fatty acid compositions were that tetradecanoic acid was composed as important one (37.15%) for V. vulnificus and that the amount of hexadecanoic acid was very small (below 2%) for three toxic substances. The lethal toxicity in ICR mice of toxic substance from V. vulnificus (LD_50 was 52.5 ㎎/㎏) was similar to that of E. coli (56.5 ㎎/㎏), but weaker than that of S. typhimurium (37.5 ㎎/㎏). Toxic substance from V. vulnificus was more pyrogenic in rabbit than that from E. coli, but less than that from S. typhimurium.
        3.
        1996.08 KCI 등재 서비스 종료(열람 제한)
        This study was performed to investigate the relationship between concentrations of heavy metals in sediment and the depths of 27 sampling sites along the West Nakdong river in downstream of Nakdong River. The deepest site was Kangdong bridge nearby 20ft. From here, the depth was shallowed to Chidong gradually. In each site the smaller mesh was, the higer concentration of heavy metal becomed. Concentration of Zn, Cd, Cr and Cu at inflow point of Shinoe stream was 576.016 ppm, 262.307 ppm, 68.674 ppm and 61.634 ppm, respectively, the concentration was the higest at this point. From here, it was lowered gradually. The concentration of heavy metal at inflow point of Joman river was 155.328 ppm, 56.485 ppm, 25.200 ppm and 31.172 ppm, respectively, those concentrations were higer than other points with the exception of Shinoe stream. Therefore, Joman river and Shinoe stream were the major source of pollution in West Nakdong river. Among two sources Shinoe stream was more important source of pollution. West Nakdong river has become lake by Noksan floodgate because it`s pollution has had influence on Bonglim.
        4.
        1996.08 KCI 등재 서비스 종료(열람 제한)
        This study was conducted to evaluate the level of atmospheric heavy metals and the relationship of that concentration with weather conditions. This research monitored the concentration of Total Suspended Particulates (TSP) at every three hours by using High Volume Air Sampler from December 24th, of 1995 to Febuary 20th, 1996 in Kimhae area, which recently became a rapidly growing residential and industrial sitc. The items such as air-temperature, relative humidity, radition, wind speed, and wind direction were monitored by using Atmospheric Weather System at the same time. From the collected TSP, the concentration of heavy metals were analyzed by using the Atomic Absorption Spcetrophotometry. The mean concentration of TSP was 110.4 ㎍/㎥, and the mean concentration of lead (Pb), copper (Cu), chromium (Cr), manganese (Mn), cadmium (Cd), were 0.837 ㎍/㎥, 0.486 ㎍/㎥, 0.264 ㎍/㎥, 0.157 ㎍/㎥, 0.054 ㎍/㎥, respectively. Regarding daily variations, the concentration of TSP was highest in the morning (158.1 ㎍/㎥) followed by evening (119.4 ㎍/㎥) and afternoon (111.1 ㎍/㎥). The concentration of Pb and Mn was higher in the morning, and that of Cu, Cr and Cd was higher in the afternoon and the evening. Regarding the relationship between the concentration of pollutants and weather condition, the concentration TSP revealed positive correlation with temperature, humidity, wind speed, but negative correlation with radition (p<0.01). The concentration of Mn revealed positive correlation with temperature and humidity, but negative correlation with wind speed (p<0.01). And the the concentration of pollutants and weather condition revealed higher correlation within the same time period. In summary, the paralleled mornitoring of air conditions and weather condition should be recommended to get the correct informations concerning the pollution and to prevent the deterioration of air conditions.
        5.
        1996.06 KCI 등재 서비스 종료(열람 제한)
        This project studies marine Vibrio vulnificus in oysters in the marine environment and attempts to correlate this bacteria`s presence within various environmental parameters; we design this study to determine how different storage temperatures affect the survival of V. vulnificus in oysters and whether V. vulnificus is able to persist in oysters after exposure to UV light-disinfected seawater. Experimental depuration systems consist of aquaria containing temperature-controlled seawater treated with UV light and 0.2 ㎛ pore size filtration. Results showed that depuration at temperatures higher than 25℃ caused V. vulnificus counts to increase in oysters. Throughout the process, depuration water contained high concentrations of V. vulnificus, indicating that the disinfection properties of UV radiation and 0.2 ㎛ pore size filtration were less than the release of V. vulnificus into seawater. In contrast, when depuration seawater was maintained at 10℃, the numbers of V. vulnifcus were very little and multiplication in oysters was inhibited.
        6.
        1996.04 KCI 등재 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.