• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.291-297
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• 2005

• Cement Symposium
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• s.34
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• pp.160-166
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• 2007

• Journal of Korean Society of Environmental Engineers
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• v.27 no.6
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• pp.599-605
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• 2005

The characteristics of PCDD/Fs were studied when accumulating on 1 to 4 year old pine needles that were used as passive samplers of atmospheric POPs. The rate of concentration increase was linear in lower(tetra- through hexa-) chlorinated PCDD/Fs, but higher (hepta- and octa-) chlorinated homologue concentrations did not increase with needle age. The lower were in gas phase and the higher in particles. Photodegradation rates of PCDDs on pine needles were similar to PCDFs, higher chlorinated PCDD/Fs tend to photolyze quickly. Therefore it is recommended that the younger needles should be collected to avoid errors from the depositional accumulation rates and photodegradation, and that, when comparing local concentrations of PCDD/Fs, needles of same age should be collected to reduce the errors.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.13 no.5
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• pp.67-75
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• 1993

This study was performed for the purpose of estimating steel corrosion and of considering a countermeasure to prevent steel corrosion of concrete structures under the environment of seawater or using seasand. The corrosion of steel was accelerated in artificial seawater with seven kinds of specimen which was embedded steel in mortar. To assume the degree of steel corrosion, soluble chloride content in mortar, $Cl^-$ binding capacity, half cell potential and corrosion area ratio were measured. The results show that corrosion area ratio was correlative with half cell potential and soluble chloride content in mortar.

• Korean Journal of Food Science and Technology
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• v.12 no.3
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• pp.141-149
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• 1980

In order to determine the residue levels of organochlorine insecticides in cow's milk, 66 commercial milk samples were collected from markets in major cities of Korea and analyzed for their fat contents and pesticide residue levels. The fat contents were in the range of $2.65{\sim}3.87%$, the average being 3.35%. The average residue levels of organochlorine insecticides on fat basis (whole milk basis in parentheses) were 0.196 ppm (0. 0066 ppm) of ${\alpha}-BHC$, 0.159ppm (0.0055 ppm) of ${\beta}-BHC$, 0.066 ppm (0.0022 ppm) of heptachlor epoxide and 0.042ppm (0.0015 ppm) of DDE. Heptachlor, DDT and drin insecticides were not detected. These residue levels corresponding to $1/10{\sim}1/50$ of tolerance levels adopted in Japan appear to exhibit no adverse effect as yet from the standpoint of food safety.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.3
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• pp.184-189
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• 1993

Orchardgrass(Dactylis glomerata L.) hays, which had been harvested in different seasons and grown with different levels of potassium (K)fertilizer, were fed to foats in metabolic cages in order to know the effect forage mineral content on mineral balance of goats. The K contents of the feed were 3.4, 4.9 and 5.8% and magnesium (Mg) contents were 0.26, 0.21 and 0.21% on a det matter(DM) basis in K-low, K0medium and K-high treatments, respectively. Urinary K excretion was significantly more on K-high than on K-low treatment. Faecal and urinary Mg excrerions on K-low were higher than those on K-medium and K-high feeds. And there was a tendency of positive relation between urinary Mg excretion and serum Mg concentrarion. Goats on K-high treatment seemed to drink more water and excrete more urine than those on the other feeds.

• Journal of Environmental Science International
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• v.5 no.5
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• pp.569-577
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• 1996

pure compound chloromethanes; methyl chloride, methylene chloride, chloroform and The carbon tetrachloride were used as a model of chlorocarbon system with Cl/H ratio to investigate thermal stability and hydrodechlorination process of carbon tetrachloride under excess hydrogen atmosphere. The parent thermal stability on basis of temperature required for 99% destruction at 1 second no was evaluated as $875^{\circ}C$ for $CH_3Cl$, $780^{\circ}C$ for $CH_2Cl_2$, $675^{\circ}C$ for $CHCl_3$ and $635^{\circ}C$ for $CCl_4$. Chloroform was thermally less stable than $CCl_4$ at fairly low temperatures $(<570^{\circ}C).$ The lion of $CCl_4$ became more sensitive to increasing temperature, and $CCl_4$ was degraded CHCl3 at above $570^{\circ}C.$ The number and quantity of chlorinated products decreases with increasing temperature for the Product distribution of $CCl_4$ decomposition reaction system. Formation of non-chlorinated hydrocarbons such as $CH_4$, $C_2H_4$ and C_2H_6$ increased as the temperature rise and particularly small amount of methyl chloride was observed above $850^{\circ}C$ in $CC1_4$/$H_2$ reaction system. The less chlorinated products are more stable, with methyl chloride the most stable chlorocarbon in this reaction system.

• Applied Biological Chemistry
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• v.50 no.1
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• pp.42-47
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• 2007

Effect of chlorine dioxide ($ClO_2$) treatment on the microbial and physicochemical changes of fish paste was investigated. Fish paste samples were treated with 5, 10, and 50 ppm of $ClO_2$ solution, respectively, After $ClO_2$ treatment, fish paste samples were individually packaged and stored at 4$^{\circ}C$. The initial microbial loads of samples were 3.8 log CFU/g in total bacterial count, and 2.5 log CFU/g in yeasts and molds. Microbial growth of fish paste during storage showed that populations of total bacteria, yeast and mold were significantly reduced by $ClO_2$ treatment. In particular, the treatment of 50 ppm $ClO_2$ decreased total bacterial count the most significantly among the $ClO_2$ treated fish pastes. The pH and VBN of fish paste decreased with increasing $ClO_2$ concentration. Thiobarbituric acid reacted substance (TBARS) values of treated fish paste increased during storage, regardless of $ClO_2$ concentration. This study showed that 50 ppm chloride dioxide was the optimum dose level to extend the shelf-life of fish paste.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 2000.11a
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• pp.83-84
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• 2000

식물은 반휘발성유기화합물(Semivolatile organic compounds : 이하 SOCs)의 지구적인 순환과 먹이 연쇄에 있어서 중요한 역할을 한다. 또한 식물은 대기중 가스상 SOCs을 보유하고 입자상 SOCs를 제거하는 역할을 하기 때문에 대기를 정화하는데 중요한 기능을 한다(Lorber et al, 1993). SOCs 화합물 중 PCBs와 BHCs는 친지질성(lipophilic) 유기염소계 화합물로 식물의 뿌리를 통해서는 흡입되지 않고 대기중에서 식물잎의 표면에 존재하는 지질에 침착되므로 식물잎에 침착된 오염물질은 대기의 농도에 의존한다. (중략)

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.3
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• pp.201-208
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• 1994

In order to study the effect of exsisting soil nutritional elements on the nitrogen uptake of sunflower, sorghum and black gram, pot experiment was carried out by using soils sampled from three different depths(0~20, 45~65, 90~110cm) of Brigalow soil in Australia. The results obtained were as follows : Dry matter and nitrogen uptake of corps were increased in the soil with higher nitrogen content. Chlorine uptakes of sunflower and sorghum were increased in the soil with higher nitrogen and lower chlorine contents, but that of black gram was done in the soil with higher contents of both elements. Ratios of nitrogen derived from applied fertilizer of three corps and fixed nitrogen of black gram were relatively low in the soil with higher content of soil nitrogen, but those derived from soil nitrogen were reverse. Recovery rates of applied nitrogen were relatively increased with higher cation uptakes of crops. Chlorine uptakes of sunflower and sorghum were positively correlated with each recovery of nitrogen, but that of black gram didn't show the trend. Recovery rate of applied nitrogen for black gram had significantly negative correlation with increase of soil chloride content.