• 한국식품영양학회지
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• 제33권1호
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• pp.1-8
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• 2020

The purpose of this study was to prevent excessive softening of seasoned spinach by heating and freezing through the pre-heating treatment in calcium chloride solution. The pre-heating temperature was set at 60℃, which supports the highest activity of pectinesterase around 60℃. Pre-heating spinach in calcium solution does not affect the chromaticity characteristics of spinach leaves and significantly improves its texture compared to conventional blanching only and pre-heating in water. The improvement of the firmness is related to the formation of strongly cross-linkages between carboxyl groups and Ca²⁺ by the action of the pectinesterase in spinach. For reheated spinach, the firmness of calcium chloride treated stems were 37.80~44.44 kg, and the control was 28.73 kg. The firmness of calcium chloride treated leaves was 19.73~40.79 kg, and the control was 9.63 kg. Additionally, the total aerobic bacteria in the fresh samples were 3.25~3.99 log CFU/g and 1.97~2.72 log CFU/g in the reheated samples. And the total coliform was not detected in the reheated samples. Considering the color, texture, microbial characteristics and taste quality, the optimum pre-treatment conditions to prevent excessive softening of spinach were 3% calcium chloride solution and 15minutes of treatment.

• 콘크리트학회논문집
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• 제15권2호
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• pp.345-351
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• 2003

The transport characteristics of deleterious ions such as chlorides depend on the pore structures of concrete and are the major factors in the durability of concrete structures in subjected to chloride attack such as in marine environments. In this paper, the effect of the pore structure on compressive strength and chloride diffusivity of concrete was investigated. Six types of concretes were tested. The pore volume of concrete containing mineral admixtures increased in the range of 3∼30nm due to micro filling effect of hydrates of the mineral admixtures. There was a good correlation between the median pore diameter, the pore volume above 50nm and compressive strength of concrete, but there was not a significant correlation between the total pore volume and compressive strength. The relationship between compressive strength and chloride diffusivity were not well correlated, however, pore volume above 50nm were closely related to the chloride diffusion coefficient.

• Nuclear Engineering and Technology
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• 제47권7호
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• pp.867-874
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• 2015

Separation of cesium chloride (CsCl) and strontium chloride ($SrCl_2$) from the lithium chloride-potassium chloride (LiCl-KCl) salt was studied using a melt crystallization process similar to the reverse vertical Bridgeman growth technique. A ternary $SrCl_2-LiCl-KCl$ salt was explored at similar growth rates (1.8-5 mm/h) and compared with CsCl ternary results to identify similarities. Quaternary experiments were also conducted and compared with the ternary cases to identify trends and possible limitations to the separations process. In the ternary case, as much as 68% of the total salt could be recycled per batch process. In the quaternary experiments, separation of Cs and Sr was nearly identical at the slower rates; however, as the growth rate increased, $SrCl_2$ separated more easily than CsCl. The quaternary results show less separation and rate dependence than in both ternary cases. As an estimated result, only 51% of the total salt could be recycled per batch. Furthermore, two models have been explored to further understand the growth process and separation. A comparison of the experimental and modeling results reveals that the nonmixed model fits reasonably well with the ternary and quaternary data sets. A dimensional analysis was performed and a correlation was identified to semipredict the segregation coefficient.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2006년도 춘계 학술발표회 논문집(II)
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• pp.493-496
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• 2006

Steel corrosion in concrete is aggravated with the increase of chloride content in concrete. So, there are regulations in the total amount of chloride ions in concrete in Korea and Japan. The purpose of this paper is to propose a resonable method to regulate the amount of chlorides in concrete. In this study, the experimental results showed that it is rather reasonable to regulate the amount of chloride ions in cement than the total amount of the chloride ions in concrete.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1994년도 가을 학술발표회 논문집
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• pp.87-92
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• 1994

The main objective of this study is to determine the critical chloride ion concentrations in the pore solutions causing depassivation of steel reinforcement in concrete made with cements of different $C_3A$ contents. Cement pastes with water-ratio of 0.5 were prepared using four cements with $C_3A$ contents of 0.46, 5.97, 9.14, and 9.65 percent. The pastes were allowed to hydrate in sealed containers for 28days and then objected to pore solution expression. The expressed pore fluids were analyzed for chloride and hydroxyl ion concentrations. It was found that the free cholride concentration in the pore solution decreases significantly with an increase in the $C_3A$ content of the cement. With increasing level of chloride addition, although the alsolute amount of bound chloride increase, the ratio of bound to total chlorides decreases.

• 한국환경보건학회지
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• 제22권2호
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• pp.114-123
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• 1996

Escherichia coli에 copper chloride 50 ppm, manganese chloride 100 ppm, nickel chloride 100 ppm을 각각 처리하여 세포를 배양하는 동안에 이들 세포에서 일어나는 인지질 생합성 및 지방산 조성의 변화를 대조구와 비교하여 분석하였다. 세포의 생장과 total lipid, phosphatidylethanolamine, phosphatidylcholine, phosphatidylglycerol, cardiolipin은 대조구조에 비해 금속 화합물 처리구에서 저해되었는데 nickel chloride가 가장 큰 억제 효과를 나타내었다. 그러나 phosphatidylinositol은 금속화합물의 영향을 받지 않았다. 인지질 생합성에 이용된 주요 지방산은 대조구는 palmitic acid(평균 25.47%)와 palmitoleic acid(평균 12.27%)가 인지질 생합성에 도입되었고 copper chloride 처리구는 palmitic acid(평균 30.13%)와 stearic acid(평균 9.12%)로 나타났다. manganese chloride 처리구와 nickel chloride 처리구에서는 모두 palmitic acid(평균 24.16%, 평균 21.77%)와 linoleic acid(평균 9.48%, 평균 11.88%)가 인지질 생합성에 이용된 주요 지방산으로 분석되었다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2003년도 봄 학술발표회 논문집
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• pp.699-704
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• 2003

Corrosion of reforcement is the main cause of damage and early failure of reinforced concrete structures. The corrosion is mainly progressed by the chloride ingress. In this paper, an experimental study is executed to investigate the effect of concrete properties and testing method on the coefficient of chloride diffusion. Also, it is compared that the relationship between total chloride and free chloride in concrete. According to this experiment results, w/c ratio and testing method effect on chloride diffusion coefficient of concrete. As w/c ratio is increased, diffusion coefficient in concrete is also increased. Diffusion coefficient obtained by each testing method show the different value, respectively. Also, the content of free chloride in 7days curing concrete is increased as w/c ratio is increased.

• 한국식품영양학회지
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• 제29권6호
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• pp.946-951
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• 2016

In this study, Ilex serrata Thunb was extracted with 70% methanol and concentrated under reduced pressure to measure its total polyphenol contents; furthermore, we examined the effect of electron donating ability of the various extracts. The extract was fractionated using different solvents such as methylene chloride, ethyl acetate, and methanol to investigate total polyphenol contents and electron donating abilities. The total polyphenol contents were $1,058.59{\pm}85.85{\mu}g\;GAE/mL$ in 70% methanol, $297.29{\pm}29.43{\mu}g\;GAE/mL$ in methylene chloride, $313.28{\pm}9.22{\mu}g\;GAE/mL$ in ethyl acetate, and $837.82{\pm}31.16{\mu}g\;GAE/mL$ in methanol. The total polyphenol contents showed significant differences (p<0.05) between the solvents. The electron donating abilities were $72.93{\pm}0.29%$ for 70% methanol extract, $14.02{\pm}2.01%$ for methylene chloride, $24.05{\pm}1.75%$ for ethyl acetate, and $84.08{\pm}1.95%$ for methanol. The electron donating abilities were significantly different (p<0.05) between the solvents. The two portions of Ilex serrata Thunb extracts obtained from methanol showed significantly relevant results in the total polyphenol contents and electron donating ability, which was higher than the original extract.

• The Korean Journal of Physiology
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• 제9권1호
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• pp.23-32
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• 1975

In order to study the dally metabolism of sodium chloride and of nitrogen, 24-hour urine samples were collected from 1,593 normal Korean females whose ages varied from 2 to 80 years old. The volume, the concentration of chloride and the osmolality of the urine, add the total nitrogen were determined, along with the resting pulse rate and the blood pressure. The daily urine volume was maintained at $1,000{\sim}1,300\;ml/m^2/day$ in all age groups while the chloride concentration and osmolality of the urine samples were approximately 200 mEq/liter and 600 milliosmoles, respectively, in most of age groups. Hence the daily urinary output of sodium chloride was estimated to be approximately $15g/m^2$/day in adult groups. On the other hand, the daily excretion of total nitrogen amouted to approximately $5{\sim}6g/m^2/day$. These findings indicated that the average Korean females live on low-protein and high-salt diets throughout their life. Despite a known correlation between the incidence of hypertension and the high salt intake, none of the subjects employed in this work showed any sign of hypertension.

• 약학회지
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• 제34권3호
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• pp.206-211
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• 1990

Total suspended particles were collected and size-fractionated by an Andersen high-volume air sampler at Chungang University located near the Han River, Seoul, Korea, during the period form March, 1986 to August, 1986 and from March, 1987 to February, 1988. The concentrations and the particle size distributions of anions such as chloride, nitrate and sulfate were determined by ion chromatography. The averages of concentrations were $125.43\;{\mu}g/m^3$ in 1986 and $189.19\;{\mu}g/m^3$ in 1987 for total suspended particles (TSP), $2.12\;{\mu}g/m^3$ in 1986 and $4.14\;{\mu}g/m^3$ in 1987 for chloride, $4.39\;{\mu}g/m^3$ in 1986 and $5.95\;{\mu}g/m^3$ in 1987 for nitrate and $11.98\;{\mu}g/m^3$ in 1986 and $19.29\;{\mu}g/m^3$ in 1987 for sulfate. Size distribution of TSP was found to be generally bimodal. Chloride exhibited a seasonal variation in the distribution; fine particles were predominant in the winter whereas the concentration of coarse ones was almost same through four seasons. Nitrate showed a distribution similar to that of chloride. Such variation was less significant for sulfate. For chloride and nitrate, the relationship between the monthly averaged distribution pattern and air temperature was analyzed in terms of fine fraction (FF). The FF decreased with increasing air temperature.