• Proceedings of the Korea Society of Environmental Biology Conference
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• 2002.11a
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• pp.15-24
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• 2002

Polychloinated biphenyls (PCBs) 및 유기염소계 농약은 UNEP에서 지속성유기오염물질(POPs)로 규정하고 있는 화합물로서 환경내 잔류성이 강하고 먹이사슬을 딸라 생물증폭되는 화합물로 알려지고 있다. 광양만의 유기염소계화합물의 오염현황을 파악하고자, 표층퇴적물, 생물, 해수 중의 농도를 정량ㆍ정성분석하였다. 해수의 용존상을 제외한 모든 매질에서 PCBs와 DDT 화합물이 주요 유기염소계 화합물로 검출되었다. 퇴적물 중의 총 PCBs, DDTs, CHLs(클로르단 화합물), HCHs (헥사클로르사이클로헥산)의 농도는 각 각 0.61-1.97 ng/g, 0.16-1.16 ng/g, nd-0.51 ng/g, 0.05-0.79 ng/g의 농도 범위를 나타냈다. 퇴적물 중의 유기염소계화합물의 농도수준은 우리나라 주요 만 (부산만, 영일만, 울산만, 경기만)에서 조사된 퇴적물 중의 농도와 비교할 때 낮은 수준이며, 저서생물에 독성학적 위해를 일으킬 수 있는 수준에 미치지 못한다. 이매패류 중의 유기염소계화합물의 농도는 총 PCBs (4.42-19.ng/g), 총 BBTs (7.54-22.6ng/g), CHLs (0.49-2.0ng/g), HCHs (0.82-7.32ng/g)의 범위를 나타었다. PCBs의 경우 산업시설 및 도시 주변에서 상대적으로 높았으나 전반적으로 비슷한 수준을 나타냈다. 해수 중의 PCBs 농도는 제철소 인근에서 상대적으로 높았으며, 해수의 용존상에서는 입자상에서와 달리 DDTs보다 HCHs가 상대적으로 높은 농도로 검출되었다. 이는 두 상에 분배되는 이들 화합물의 성향에 따르는 것으로 파악된다.

• Analytical Science and Technology
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• v.23 no.1
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• pp.45-53
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• 2010

For the determination of chlorine in uranium compound, analytical methods by using a steam distillation and a pyrohydrolysis have been developed. The steam distillation apparatus was composed of steam generator, distilling flask and condenser etc. The samples were prepared with an aliquot of LiCl standard solution and a simulated spent nuclear fuel. A sample aliquot was mixed with a solution containing 0.2 M ferrous ammonium sulfate-0.5 M sulfamic acid 3 mL, phosphoric acid 6 mL and sulfuric acid 15 mL. The chloride was then distilled by steam at the temperature of $140^{\circ}C$ until a volume of $90{\pm}5\;mL$ is collected. The pyrohydrolysis equipment was composed of air introduction system, water supply, quartz reaction tube, combustion tube furnace, combustion boat and absorption vessel. The chloride was separated from powdered sample which is added with $U_3O_8$ accelerator, by pyrohydrolysis at the temperature of $950^{\circ}C$ for 1 hour in a quartz tube with a stream of air of 1 mL/min supplied from the water reservoir at $80^{\circ}C$. The chlorides collected in each absorption solution by two methods was diluted to 100 mL and measured with ion chromatography to determine the recovery yield. For the ion chromatographic determination of chlorine in molten salt retained in a metal ingot, the chlorine was separated by means of pyrohydrolysis after air and dry oxidation, and grinding for the sample.

• Proceedings of the Membrane Society of Korea Conference
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• 1993.10a
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• pp.54-55
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• 1993

유기염소계 화합물들은 저렴한 가격과 우수한 세정력으로 기계, 금속, 섬유산업에서 뿐만아니라 일반적인 용제로도 널리 사용되고 있다. 그러나, 현재 산업현장에서사용 후 처리에 있어 유기염소계 화합물들을 완전히 제거하지 못하고 방출하는 실정이다. 또한, 음용수제조시 행해지는 염소소득으로 미량의 트리할로메탄(THM)인 클로로포름이 생성된다. 이러한 유기염소계 화합물들은 음용수 중에 포함되어 체내로 흡수되면 암을 유발시킨다. 따라서 물중에 용해된 미량의 유기염소계 화합물들을 제거하는 것이 필수불가결한 실정이다.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1747-1748
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• 2008

정수처리시스템에서의 염소소독공정은 염소투입설비의 지연요소와 염소반응시간에 의한 지연요소 등으로 매우 큰 시지연특성을 갖는 대표적인 공정이다. 본 논문에서는 염소소독공정 중 후염소공정을 조사 분석하여 공정에 영향이 큰 파라메타를 선정하고 이를 통하여 각 파라메타간 상관관계를 분석함으로써, 시지연공정의 모델을 개발하였다.

• Journal of Animal Science and Technology
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• v.54 no.4
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• pp.241-246
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• 2012

The goal of this study was to verify the phylogenetic status of the Korean native goats (KNG). We determined the complete sequence of the mitochondrial cytochrome b gene in 48 goats among four populations. We also analyzed genetic variability within goats, and a phylogenetic analysis was performed by comparison with other country's goats. Three nucleotide substitutions were detected, and two of these were missense mutations that occurred due to a substitution of amino acid. Four haplotypes were defined from KNG. Three of these haplotypes were only found in the Chinese goat. However, the other haplotype was KNG-specific. In the phylogenetic analysis, four clades (A~D) were classified among domestic goats, and the KNG was classified into clade 1 that estimated as lineage A based on the D-loop sequence. Each haplotype from the KNG was clustered closely with that of the Chinese goat. The results of haplotype distribution and phylogenetic location suggest that strong gene flow occurred from China to the Korean Peninsula.

• Resources Recycling
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• v.27 no.5
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• pp.54-60
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• 2018

The quality of steel produced from scrap can be adversely affected because of the buildup of tramp elements in recycled scrap. The tramp element of greatest concern is copper because of its effect on steel quality, even in small percentage quantities. In this study, possibility of removal of copper from ferrous scrap by using $Cl_2$ gas is experimentally examined in a small size experimental apparatus. Synthetic ferrous scraps containing copper were reacted with $Cl_2$ gas in various atmosphere. The copper was chloridized and evaporated, whereas iron was oxidized and was not reacted with Cl2 and oxygen mixture gas.

• Journal of the Korean Chemical Society
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• v.44 no.1
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• pp.74-80
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• 2000

The purpose of this study is to analyze comparatively and improve the preparation of chlorine gas in the high school chemistry II textbooks on the basis of the revised curriculum. From the results of the preparation experiment of chlorine gas which is commonly dealing with 9 kinds of textbook in the nation, we have found some problems and have suggested the solution of these problems. The problem is the students may inhale the chlorine gas that is to be injurious on the human body, so the research is focused on safe experimental method without inhalation of chlorine gas. The simple conviction method of character in laboratory is to propose at 5 kinds.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.15-20
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• 2009

Marine concrete structure is exposed to salt injury and deteriorated by steel corrosion due to chloride ions diffusion. It, therefore, is very important to estimate the chloride diffusivity in concrete. In this paper the compressive strength and permeable pore volume of concrete are measured and the diffusion coefficient and penetration depth of chloride ions in concrete were investigated to estimate the chloride diffusivity efficiently. To correlate these results each other, regression analysis was done. The results showed a good linear relation between chloride diffusivity and the fundamental properties of concrete and the chloride diffusivity of concrete with water-cement ratios of $40%{\sim}60%$ were about $2.5{\sim}6.6{\times}10^{-12}m^2/s$.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 1998.11a
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• pp.329-334
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• 1998

난연성을 지닌 고분자 물질중 Chlorosulfonated Polyethylene(CSPE; Hypalon)은 Polyethylene에 염소와 황을 첨가한 것으로 염소를 첨가함으로써 기름과 화염에 대한 저항성을 향상시키고, 황 또한 기름, 화염에 대한 저항을 향상시킬 뿐 아니라 인장강도를 크게 해서 기계적 강도를 향상시킨 것이다. CSPE는 염소량의 등급에 따라 Coating재료, 호스 구조재, Wire와 Cable의 피복재료등 여러 가지 용도로 많이 쓰이고 있으며 특히 염소함량이 35%인 CSPE(Hypalon-40)의 경우 열저항과 압출 특성이 우수하기 때문에 Cable의 피복재료로 많이 쓰이고 있다.

• Journal of Life Science
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• v.21 no.9
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• pp.1329-1335
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• 2011

Korean native goats, which are characterized by black coat color, have existed on the Korean peninsula for a long time. Until now, there has been no comprehensive investigation concerning their genetic diversity, phylogenetic analysis or origin. In this study, we investigated the genetic diversity and verified phylogenetic status of the Korean native goat using the 453-bp fragment of the hypervariable fragment I (HVI) of mitochondrial DNA (mtDNA) D-loop region from 60 individuals among 5 populations. The Korean native goat showed less haplotype diversity when compared with goats from other countries. In addition, 6 haplotypes that had not been previously reported were verified in this study. In phylogenetic analyses with other country's goats, 10 haplotypes from Korean native goats were classified into mtDNA lineage A. Moreover, in a phylogenetic tree for goats which contained mtDNA lineage A, 8 of 10 haplotypes could be included in a subgroup with goats from Vietnam and an area of China. However, none of the remaining haplotypes belonged to a major group of Korean native goats and were located on different independent positions. These results suggest that almost Korean native goats aligned more closely to China and Vietnam breeds in mtDNA lineage A and there was no gene flow from other mtDNA lineages. Our results will contribute to conservation strategies and genetic breeding of Korean native goats.