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        검색결과 43

        1.
        2016.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구에서는 제주도에서 규모가 가장 큰 항구인 제주항내 퇴적물을 대상으로 PCBs의 분포특성을 연구하였다. 연구 결과, 제주항 내 표층퇴적물에서 PCBs 화합물의 농도범위는 1.62∼4.45 ng/g dw로 낮은 농도로 분포하고 있었고, PCBs의 동족체 패턴 분석을 보면 제주항은 선박 활동으로 유래되는 고염소화된 CBs(Hexa-CBs 이상)이 주로 분포하였다. 퇴적물에서 PCBs 화합물의 분포에 미치는 유기물의 영향을 평가하기 위하여 퇴적물 내 유기탄소 함량과 PCBs 화합물의 농도와의 상관관계를 검토한 결과, R2이 0.8387로 높게 나타나 유기탄소 함량과 PCBs 농도는 매우 유의한 상관성을 보이는 것을 알 수 있었다. PCBs 화합물의 농도분포와 입자크기와의 관계에서 역질, 사질, 니질로 나누어 조사하였는데 니질의 함량이 증가할수록 PCBs의 농도도 높게 분포하였다. 그리고 연구지역의 표층퇴적물에서 분포하고 있는 PCBs의 농도를 국외에서 적용하고 있는 퇴적물오염기준(sediment quality guidenes, SQGs)의 ERL(effect range-low)과 TEL(Threshold Effects Level) 값과 비교한 결과, 훨씬 낮은 값을 보여 생태독성학적 관점에서 저서생물에 미치는 영향은 미미한 것으로 사료된다.
        4,000원
        3.
        2014.08 KCI 등재 구독 인증기관 무료, 개인회원 유료
        폐 PCBs의 스크랩으로부터 염소-차아염소산염 용액을 이용하여 Au와 Ag를 친환경적이고 효과적으로 용출시키고자 하였다. PCBs에 Cu, Sn, Sb, Al, Ni, Pb, Au 등과 같은 유용금속이 함유되어 있는 것을 EDS 분석으로 확인하였다. 최대 Au 용출율은 1%의 광액농도, 2:1의 염산:차아염소산나트륨 그리고 2 M의 NaCl 농도조건이다. Au 회수율이 가장 높은 메타중아황산나트륨 농도는 3 M에서였다. 염소-차아염소산염이 폐 컴퓨터에 함유되어 있는 Au와 Ag를 효과적으로 용출시킬 수 있는 용매제 임을 그리고 메타중아황산나트륨이 Au를 간단하게 침전시킬 수 있는 첨가제임을 확인하였다.
        4,000원
        8.
        2004.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        본 연구는 PCBs가 칼납자루의 생식에 미치는 영향을 조직학적인 방법을 사용하여 조사하였다. 0, 3.4, 9.3 그리고 25.8 μg L-1의 PCBs에 8주 동안 노출 실험한 결과, PCBs에 의한 행동과 생존율에는 영향을 미치지 않았다. 대조구와 비교해볼 때 PCBs에 노출된 어류들은 생식소발달, 생식소중량지수 (GSI), 간중량지수 (HSI), 혼인색지수(NCI) 및 산란관지수(OLI)의 차이를 보였다. 이러한 결과는 PCBs
        4,000원
        9.
        2004.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        PCB 화합물 및 유기기염소계농약류는 난분해성이며 독성이 높은 대표적인 유기오염물질로서 환경 중에 배출되면 오랜 시간 잔류하게 된다. 대부분의 유기염소계화합물은 우선적 관찰 및 규제 대상물질로 분류되어 지구적 관심을 모으고 있다. 광양만은 대단위의 공업단지가 밀집해있고 반폐쇄적인 지형학적 구조를 가지고 있어 유기염소계화합물의 오염이 우려되는 대표적인 해역이다. 본 연구에서는 오염 모니터링에 대표적으로 이용되는 퇴적물과 부착성 이매패류를 채집하여 분석함으
        4,000원
        10.
        1999.03 KCI 등재 구독 인증기관 무료, 개인회원 유료
        The new approach using the Peak Pattern Method was conducted for the analysis of polychlorinated biphenyls (PCBs) from the papers or paper products to provide certain hygienic data for the recycled papers as well as white papers. The height of the each peak, obtained from the PCBs standards, was transformed to the spectrum to compare with that of the samples. In addition to the results of the single PCBs standards, the pattern of mixed PCBs standards with the adequate concentration and ratios were obtained prior to the analysis of the paper samples. The test showed excellent repetition within 5% variation, and the recoveries of PCBs ranged from 92% to 97%. The PCBs, considered as a hazard material, were analyzed using the Peak Pattern Method from six different types of paper samples including the roll tissue. It could not find the same pattern of the PCBs peaks from all of the paper samples.
        4,000원
        11.
        1977.12 KCI 등재 구독 인증기관 무료, 개인회원 유료
        Polychlorinated Biphenyls (PCBs)는 유기염소계 농약잔류성분의 GLC분석에 간섭하는 물질이다. 본 실험에서는 PCBs의 존재하에 대표적인 유기염소계 농약 및 이들의 주요대사물의 분석을 목저르오 Florisil column상에서 PCBs와 농약성분의 분리를 시도하였다. 활성화한 Florisil column에서 , Heptachlor, epoxide, Dielerin, p.p'-DDD, p.p'-DDT와 Aroclor 1254는 완전히 그리고 정량적으로 분리하여 GLC로 분석할 수 있었다. Heptachlor와 Aldrin은 Aroclor와 함께 elution되나 Chromatogram 상에서 정량이 가능하였다. 본 시험에서 사용한 Florisil column chromatography는 많은 시료를 대상으로 한 잔류농약의 효과적 분석에 사용될 수 있다.
        4,000원
        12.
        2017.05 KCI 등재 서비스 종료(열람 제한)
        Measurements of polychlorinated biphenyls (PCBs) were taken in surface sediments inside Seogwipo and Hallim Harbors of Jeju Island, Korea, to evaluate their distribution. These harbors typically have heavy ship traffic. The samples were collected three times (in June, October, and December, 2013). PCB concentrations in sediments from Seogwipo Harbor were higher than in those from Hallim Harbor, but both levels were very low, compared with those in other parts of the world. Sedimentary PCB levels had a strong correlation with organic carbon and fine granule mud content. PCB concentration values in the examined surface sediments were much lower than Sediment Quality Guidelines (SQGs) such as ER-L (Effect Rrange-Low), TEL (Threshold Effects Level) and ISQG (Interim Sediment Quality Guideline)-low value applied in countries, such as USA, Canada, and Australia. This suggests that the PCBs did not have significant biological effects on benthic organisms in the marine environment.
        13.
        2015.02 KCI 등재 서비스 종료(열람 제한)
        The main objective of this study is to recovery valuable metals with metal particle size distributions in waste cell phone PCBs(Printed Circuit Boards) by means of pulverization and nitric acid process. The particle size classifier also was evaluated by specific metal contents. The PCBs were pulverized by a fine pulverizer. The particle sizes were classified by 5 different sizes which were PcS1(0.2 mm below), PcS2(0.20~0.51 mm), PcS3(0.51~1.09 mm), PcS4(1.09~2.00 mm) and PcS5(2.00 mm above). Non-magnetic metals in the grinding particles were separated by a hand magnetic. And then, Cu, Co and Ni were separated by 3M nitric acid. Particle diameter of PCBs were 0.388~0.402 mm after the fine pulverizer. The sorting coefficient were 0.403~0.481. The highest metal content in PcS1. And the bigger particle diameter, the lower the valuable metals exist. The recovery rate of the valuable metals increases in smaller particle diameter with same leaching conditions. For further work, it could improve to recovery of the valuable metals effectively by means of individual treatment, multistage leaching and different leaching solvents.
        14.
        2014.01 KCI 등재 서비스 종료(열람 제한)
        In this study, PCBs and PAHs in waste oils and liquid fuel waste were analyzed. About 48 samples were collectedand analyed, for hazardous substances such as PCBs, PAHs by GC/ECD and GC/MSD. According to the analysis, seventypes of PCBs concentration was found in the range of 0.13~220.77mg/kg. The highest concentration level was foundin waste insulating and heat transmission oils (EWC 13 03 08), as 220.77mg/kg. Comparing the level of PCBs to othercountries, PCB concentration in this study was lower than that of China but higher than Japan. PAHs concentration wasin the range of ND~1,380.0mg/kg for Naphthalene, ND~1,570.0mg/kg for Phenanthrene, ND~321.2mg/kg forAnthracene, ND~44.1mg/kg for Benzo[a]pyrene, ND~80.8mg/kg for Fluoranthene, ND~14.3mg/kg for Benzo[a]anthracene and ND~8.7mg/kg for Benzo[b]fluoranthene. The concentration 7 PAH in the waste oil showed the orderof Automotive oil>Hydraulic oil>Cutting oil>Machine oil. The Benzo(a)pyrene which is known as high carcinogeniccompound was detected with low concentration. Compared to other waste from other countries, the concentration of thisstudy is higher than that of Japan and lower than that of China. The PAHs concentration was lower than Automotiveoil, Hydraulic oil, Cutting oil, Machine oil, in Spain.
        15.
        2012.12 KCI 등재 서비스 종료(열람 제한)
        The formation potential and pathway of less-chlorinated PCBs, including mono- and di-chlorinated biphenyls, was investigated when PCBs contained in transformer oil were dechlorinated by commercial treatment. Potassium hydroxide with polyethylene glycol (PEG-600) was used for dechlorination of PCBs, and its destruction efficiency to whole 209 congeners of PCBs was 97.1% on average, ranging from 95.6% to 98.2%. Homologue of mono-CBs showed the negative destruction efficiencies, while those of highly-chlorinated ones through tri- to deca-CBs showed better efficiencies than about 99%. In particular, mono-chlorinated biphenyl in meta-position (#2) was about 34-47 times enriched after dechlorination, thus the reactivity seemed to be in the order of ortho-, para-, and meta-chorinated biphenyl. Co-planar PCBs' dechlorination efficiency was averaged as high as 99.4%, but 3,4,4',5-TeCB (#81) showed a relatively lower efficiency than others' in one case. Not only sodium metal but also alkaline metal such as potassium was thought of affecting the formation or enrichment of mono-chlorinated biphenyls produced by Wrutz-Fittig reaction as intermediates and products.
        16.
        2012.11 KCI 등재 서비스 종료(열람 제한)
        The dechlorination processes and efficiencies of PCBs contained in transformer dielectric oils were investigated on three commercial-treatment companies. Alkaline dispersion method was used for dechlorination of PCBs mainly using molten metallic sodium or potasium hydroxide with PEG, and its dechlorination efficiency to whole congeners of PCBs was 98.94% on average. Homologues of highly-chlorinated biphenyls showed better efficiencies than those of less chlorinated ones, especially mono-chlorinated biphenyl in para-position (#2) was about 37 times enriched after chemical treatment. Co-planar PCBs' dechlorination efficiency was averaged as high as 99.78%, but 3,3',4,4'-TeCB was relatively low as 96.5%. It was suggested for better dechlorination efficiency to remove the water in transformer oil prior to chemical reaction and to stir the reagents more rapidly when using alkaline dispersion method.
        17.
        2012.05 KCI 등재 서비스 종료(열람 제한)
        In this study, adsorption of polychlorinated biphenyls(PCBs) in transformer oil on powder activated carbon (PAC) and synthetic zeolite was evaluated. Adsorption characteristics of PCBs on the PAC and zeolite has been investigated in a batch system with respect to adsorbents amount and contact time. BET results showed 908 m2/g for PAC and 483 m2/g for zeolite. The adsorption capacity of PCBs increased with an increasing input amount of absorbent. The adsorption experimental results showed that PAC removed 90% of input PCBs in transformer oil while zeolite removed only 64%. Adsorption of PCBs to PAC and zeolite fit the Freundlich model well. The Freundlich parameter, Kf, for PAC and zeolite was 193.1 and 43.0 respectively, indicating that PAC is effect adsorbent for PCBs adsorption in transformer oil.
        20.
        2011.11 KCI 등재 서비스 종료(열람 제한)
        Practical disposal of transformer insulation oil laden with PCBs (polychlorinated biphenyls) by a chemical treatment has been studied in field work. The transformer insulation oil containing PCBs was treated by the required amounts of PEG (polyethylene glycol) and KOH, along with different reaction conditions such as temperatures and times. The reaction of PEG with PCBs under basic condition produces arylpolyglycols, the products of nucleophilic aromatic substitution. Removal efficiencies of PCBs in insulation oil before and after chemical treatment were examined. The removal efficiency of PCBs was very low at lower temperatures of 25 and 50℃. Under the reaction condition of PEG 600/KOH/100℃/2hr, removal efficiency of PCBs was approximately 70%, showing completely removal of PCBs containing 7~9 chlorines on biphenyl frame which appear later than PCB IUPAC Number 183 (2,2',3,4,4',5',6-heptaCB) in retention time of GC/ECD. However, when increasing the reaction temperature and time to 150℃ and 4 hours, removal efficiency of PCBs reached 99.99% without any formation of PCDDS/PCDFs during the process. Such reaction conditions were verified by several official analytical institutions. In studying the reaction of PEG with PCBs, it confirmed that the process of chemical treatment led to less chlorinated PCBs through a stepwise process with the successive elimination of chlorines.
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