• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1988.06a
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• pp.12-27
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• 1988

첨가제는 기유인 탄소와 수소로 된 유기화합물과 함께 존재하면서 윤활기능을 높여 주는 것으로써 유황, 염소와 인을 주요성분으로 하고 있다. 비록 이들 첨가제의 화학적 구조와 반응에 따라 윤활기능 및 역할을 체계적으로 연구하는 것은 매우 복잡하고 때로는 불가능 하지만 가능한 범위에서 화학적 관계와 윤활작용의 상호관계를 살펴보기로 한다.

• Tribology and Lubricants
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• v.4 no.2
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• pp.15-27
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• 1988

첨가제는 기유인 탄소와 수소로 된 유기화합물과 함께 존재하면서 윤활기능을 높여주는 것으로써 유황, 염소와 인을 주요 성분으로 하고 있다. 비록 이들 첨가제의 화학적 구조와 반응에 따라 윤활기능 및 역할을 체계적으로 연구하는 것은 매우 복잡하고 때로는 불가능하지만 가능한 범위에서 화학적 관계와 윤활작용의 상호관계를 살펴보기로 한다.

• Korean journal of applied entomology
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• v.16 no.4 s.33
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• pp.221-227
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• 1977

Polychlorinated Biphenyls (PCBs) interfere with gas chromatographic analysis of multiple organochlorine pesticide residues. In the present work, existing Florisil column chromatographic method has been modified as to improve separation of organochlorine pesticides and their metabolites from PCBs. It was amply demonstrated that separation of $\alpha-BHC,\; \gamma-BHC$ Heptachlor epoxide Dieldrin, p.p-DDD, p.p'-DDT from PCBs such as Aroclor 1254 is complete and recovery of the pesticides is found quantitative. Aldrin and Heptachlor in the Aroclor eluant can be separately analyzed by comparison of the chromatographic pattern of standard Aroclor 1254 with that of Aroclor 1254 a dmixed with the two pesticides. The Florsil column technique can be utilized in the routine evaluation of the organochlorine pesticide residues by gas chromatography.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.216-218
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• 1980

The appearance of organochlorine insecticides in 43 samples of refined vegetable oils including rapeseed, rice bran, sesame, perilla and corn oils produced in Korea in 1976 was investigated. Residue levels varied depending on the pesticide, oil source and production area. Gas-liquid chromatographic techniques were used to detect and quantify the presence of heptachlor, its epoxide, BHC, aldrin, endrin and DDT residues.

• Korean Journal of Food Science and Technology
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• v.13 no.3
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• pp.194-201
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• 1981

In order to determine the residue levels of organochlorine insecticides in various meats consumed by Korean population, 80 samples of beef, pork and chicken were collected throughout the country and analyzed for their fat contents and pesticide residue levels. Organochlorine insecticides detected in the meat samples were ${\alpha}-BHC,\;{\beta}-BHC,\;heptachlorepoxide\;and\;DDE$. The average residue levels of the four pesticides on fat basis were 0.466 ppm in domestic beef, 0.145 ppm in imported beef, 0.264 ppm in pork and 0.106 ppm in chicken, in decreasing order of ${\alpha}-BHC>DDE>heptachlorepoxide>{\beta}-BHC$. Daily intake per person of the residues from meat by Korean population was estimated to be $1.0{\mu}g$ of total BHC, $0.1{\mu}g$ of heptachlorepoxide and $0.3{\mu}g$ of DDE. This level was far below the acceptable daily intake of organochlorine insecticides $(18\;{\mu}g/㎏\;body\;weight)$ as recommended by FAO/WHO.

• Journal of Soil and Groundwater Environment
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• v.11 no.4
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• pp.18-24
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• 2006

The possibility of multiresidue analysis of 24 pesticides out of 30 residual pesticides which are subjected to test in the golf courses was examined. The utility of multiresidue method for pesticide residue test was evaluated by recovery test through a standard addition method of pesticides in water, soil, and lawn grass. The experimental results of the recovery test for individual pesticides are as follows : The number of pesticide of which average recovery rate was over 70% regardless of media was 16 pesticides. These pesticides were composed of 8 organophosphorus pesticides (chlorpyrifos, chlorpyrifosmethyl, diazinon, EPN, fenitrothion, phenthoate, phosalone, and toclofos-methyl). 4-organochlorinated pesticides (daconil, captan, endosulfan, and tetradifon), 2-pyrethroid pesticides(fenpropathrin, lambda-cyhalothrin) and 2 other pesticides (bromopropylate, pendimethalin). On the other hand, in case of dicofol, average recovery rate was over 70% for water and lawn grass but only 53.3% for soil. Therefore, the multiresidue method applied in this experiment is not appropriate for analysis of dicofol in soil. Furthermore, among 7 pesticides, 2 pesticides(amitraz and pyraclofos) showed that theirs average recovery rate deviated from criteria($70{\sim}130%$) in almost ail media, while 5 pesticides(bensulide, deltamethrin, iprodione, phosphamidon and tralomethlin) were not detected from all media by GC/NPD or GC/ECD.

• Resources Recycling
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• v.30 no.5
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• pp.10-16
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• 2021

In this study, a clinker was prepared using raw materials with CaCl₂. The characteristics of the chlorine-added clinker and cement were analyzed. The clinker modulus were set to Lime Saturation Factor (LSF) 92, Silica modulus (SM) 2.5, and Iron Modulus (IM) 1.5. The physical properties of cement using the chlorine-containing clinker were characterized. As the chlorine content increased, the free-CaO content in the clinker decreased, and that in the 2000 ppm clinker was reduced by approximately 40% compared to that in the 0 ppm clinker. There was an increase in the amount of chlormayenite, with a content of up to 3.4% present in the 2000 ppm clinker. The amounts of alite and belite also slightly increased. The compressive strength of mortar at 3 days and 7 days increased as the chlorine content increased. This trend was presumed to arise from the effect of hydration, which was promoted by the presence of chlorine. The compressive strength of 1000 ppm mortar increased by approximately 20% compared to that of 0 ppm mortar.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.8
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• pp.755-759
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• 2008

As a disinfection byproduct, N-nitrosodimethylamine(NDMA) formation was studied according to chlorine, nitrogen, and carbon composition related to monochloramine and dimethylamine(DMA) concentrations. The highest NDMA formation was observed when the dimethylamine/monochloramine ratio was close to 1, and the formation was rapidly decreased when the ratio was less or greater than 1. The formation of NDMA increased with increasing chlorine/nitrogen ratio indicating the chlorine is a limiting factor. A rapid disinfection byproduct was formed at 72 hour contact time in this study. As the previous researches, pH was a significant factor for the NDMA formation.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.5
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• pp.332-340
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• 2009

This study was conducted to analyze and determine formation potentials for chlorination disinfection by-products (DBPs) from twenty amino acid compounds with or without $Br^-$. Two of twenty amino acid compound were tryptophan and tyrosine that were relatively shown high for formation of trihalomethanes (THMs)/dissolved organic carbon (DOC) whether or not $Br^-$ presented. Other 18 compounds were shown low for formation of THMs/DOC whether or not $Br^-$ presented. Five amino acid compounds that were tryptophan, tyrosine, asparagine, aspartic acid and histidine were shown high for formation of haloacetic acids (HAAs)/DOC whether or not $Br^-$ presented. Although formation of dichloroacetic acid (DCAA) was dominated in asparagine, aspartic acid and histidine, trichloroacetic acid (TCAA) was dominated in tryptophan and tryptophan. The formation of haloacetnitriles (HANs)/DOC whether or not $Br^-$ presented was high in Aspartic acid, histidine, asparagine, tyrosine and tryptophan. Specially, aspartic acid was detected 660.2 ${\mu}$g/mg (HAN/DOC). Although the formation of chloralhydrate (CH)/DOC was shown high in asparagine, aspartic acid, histidine, methionine, tryptophan and tyrosine, the formation of Chloropicrin (CP)/DOC was low (1 ${\mu}$g/mg) in twenty amino acid compounds. The formations of THM, HAA and HAN were also investigated in functional groups of amino acids. The highest formation of THM was shown in amino acids compounds (tryptophan and tyrosine) with an aromatic functional group. Highest, second-highest, third-highest and fourth-highest functional groups for formation of HAA were aromatic, neutral, acidic and basic respectively. In order of increasing functional groups for formation of HAN were acidic, basic, neutral and aromatic.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2002.05b
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• pp.168-172
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• 2002

돈분뇨를 토양에 살포시 경과일에 따른 이온들의 용탈 특성을 살펴보기 위해 질산성 질소 농도가 높고, 양돈사육두수가 많은 서ㆍ북부 지역의 토양에 돈분뇨를 살포, 비살포시 1~32일 경과 후에 일정량의 강수(100mm)시 용탈되는 각종 이온의 용탈 정도를 검토한 결과 다음과 같은 결론을 얻었다. 토양에 134kg T-N/ha로 살포시 질사성질소는 1.18mg/L.day의 질산화가 이루어졌고, 37kg $Cl^{-}$/ha로 살포한 염소이온의 용탈율은 1일에서 4일까지는 1.0mg/L.day로 증가하다가, 그 후 0.2mg/L.day로 용탈속도가 1/5로 감소하였다. 그러나 대조구는 질산성 질소, 염소이온 모두 거의 변화가 없었다.