• Journal of Korean Society of Forest Science
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• v.80 no.3
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• pp.279-286
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• 1991

This study was carried out to investigate relationships between atmospheric $SO_2$ concentration and both soluble sulphur contents in the tree leaves and bark pH to test the possibility of using them as bioindicators for air pollution. Mt. Kwanak, Mt. Nam, Mt. Bukhan (located in Seoul) and Mt. Paldal (located in Suwon, Kyonggi-do) as polluted areas and Pyongchang, Kwangwon-do as an unpolluted area were selected for this study. Soluble sulphur contents in the leaves and hark pH of two tree species (Pines densiflora S. et Z. and Quercus mongolica Fisch.) were analyzed in May, August, and October, 1990 by $BaSO_4$ precipitation method and pH measurement, respectively. In both species, concentration of soluble sulphur in the leaves increased with increasing concentration of atmospheric $SO_2$ (correlation coefficient : 0.52). Soluble sulphur contents in the 2-year-old needles of Pines densiflora (0.170%) and current year leaves of Quercus mongolica (0.081%) in Mt. Nam in the center of Seoul were higher than those in unpolluted Pyongchang area (0.023% and 0.034%, respectively). Bark pH decreased with increasing atmospheric $SO_2$ concentration (correlation coefficient : -0.52). Bark pH of P. densiflora (pH 3.42) and Q. mongolica (pH 3.63) in Mt. Nam were lower than those in Pyongchang area (pH 3.94 and pH 4.93, respectively). Both soluble S content in the leaves and bark pH were recognized as suitable bioindicators for air pollution by $SO_2$. Especially, bark pH showed more sensitive response to air pollution by $SO_2$ than soluble S concentration in the leaves. The lowest concentration of soluble sulphur and the highest bark pH in August were considered to be due to heavy rain during the rainy season. Soluble S content in the leaves and bark pH were not significantly different at 5% level between the two species in polluted areas.

• Journal of Food Hygiene and Safety
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• v.25 no.3
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• pp.263-268
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• 2010

This study was demonstrate a repeated oral dose toxicity of detoxication sulphur in 8-weeks-old female Sprague-Dawley (SD) rats. The rats were treated with dose of 0.2%, 1%, 5% detoxication sulphur and 1% sulphur of feed consumption administered for 13 weeks. To evaluate the safety of detoxication sulfur, we examined the body weight, the feed intake, the clinical signs, the ophthalmological test, the hematological and the serum biochemical analysis. We also observed the histopathological changes of liver and kidney in rats. As a result, no significant differences in body weight, feed intake, hematological examination and histopathological between control and detoxication sulphur treatment group were found. Serum biochemical results were not shown significant differences in 0.2% and 1% the treated groups compared with control group. But glucose level were decrease, also ALT and ALP level were increase in 5% treated group. All of these results indicate that 1% detoxication sulphur of feed consumption may be safety in SD rat.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.3
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• pp.530-532
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• 1989

• Journal of Korea Foundry Society
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• v.11 no.3
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• pp.236-244
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• 1991

This paper describes a study of the nucleation and growth of graphite crystal of levitation melted high purity Fe-C-Si alloys with emphasis on hypereutectic composition. Spherulitic graphite was observed to form at high purity alloy and converted to compacted by changing the starting iron from ultra-pure zone refined iron to 99.95 pct electrolitic iron. Residual C-C clusters might be acting as an effective nucleation site for graphite, and sulphur was the element to prevent graphite from nucleating. The graphite morphology changed from compacted to spherulitic as the sulphur content decreased.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.3
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• pp.262-268
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• 2020

The IMO (International Maritime Organization) has mandated the restriction of SOx emissions to 0.5 % for all international sailing vessels since January 2020. And, a number of countries have designated emission control areas for stricter environmental regulations. Three representative methods have been suggested to cope with these regulations; using low-sulphur oil, installing a scrubber, or using LNG (Liquefied Natural Gas) as fuel. In this paper, economic analysis was performed by comparing the method of installing a scrubber with the method of using low-sulphur oil without installing additional equipment. We suggested plausible layouts and compared the pros and cons of dif erent scrubber types for retrofitting. We selected an international sailing ship as the target vessel and estimated payback time and benefits based on navigation route, fuel consumption, and installation and operation costs. Two case of oil prices were analyzed considering the uncertainty of fuel oil price fluctuation. We found that the expected payback time of investment varies from 1 year to 3.5 years depending on the operation ratio of emission control areas and the fuel oil price change.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 1996.11a
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• pp.134-139
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• 1996

The electron energy distributions function were analysed in sulphur hexaflouride at E/N : 500~800(Td) for a case of non-equilibrium ion in the mean electron energy. This paper describes the electron transport characteristics in SF$_{6}$ gas calculated for range of E/N values from 150~800(Td) by the Monte Carlo simulation and Boltzmann equation method using a set of electron collision cross sections determined by the authors and the values of electron swarm parameters. The results gained that the value of an electron swarm parameter such as the electron drift velocity, the electron ionization or attachment coefficients, longitudinal and transverse diffusion coefficients agree with the experimental and theoretical for a range of E/N. The properties of electron avalanches in an electron energy non-equilibrium region.n.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.6
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• pp.672-677
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• 1996

Volatile flavour components rates from aromatic rices were analyzed by Electronic nose systems. In functional group, polar compounds and aldehyde compounds showed much of volatile flavour components than apolar compounds, sulphur compounds and aminated compounds. The profiles of volatile flavour components rates were markedly differents of sen-sing times, amylose content.

• Journal of the Korean Home Economics Association
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• v.12 no.1
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• pp.472-479
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• 1974

In order to study the influence of sulphur-compound on the vitamin C contents of different vegetables-i.e. Korean green pepper, leaf, Bilum, leaf, Soybean sprouts, Mung bean sprouts, Cucumber-the garlic powder and minced garlic were used while the vegetables were cooked. The results garlic juice during scaling the vegetables the vitamin C contents of them were higher as much as 9.2~12.7% 2. When the scaled vegetables were seasoned the vitamin C contents were higher as much as 8.9~`17.5% by adding garlic powder and 7.3~14.9% by adding minced garlic. 3. Vitamin C loss of the cooked vegetables with room condition for 30 min, was higher as much as 15.2~34.5% compared to just cooking. 4. Vitamin C contents of vegetables after 30 min from cooking, compared to just cooking were higher of vegetables after 30 min from cooking, compared to just cooking were higher as much as shown below. 1) ~13.3% by adding garlic powder. 2) 4.0~9.3% by adding minced garlic.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2006.06a
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• pp.115-116
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• 2006

보다 깨끗한 환경에서 살고 싶어 하는 인류의 욕구가 육상의 대기 배출물뿐만 아니라 선박까지도 보다 깨끗한 배기를 요구하기에 이르렀다. 이러한 요구에 부응하여 IMO(국제해사기구)뿐만 아니라 EU(유럽연합)과 미국 등에서 규제를 이미 시작하였거나 시작할 예정이다. 또한 많은 선급에서도 약 10년 전부터 자발적인 규칙을 도입해오고 있다. 그리고 스웨덴은 인센티브제를 오래 전부터 적용해오고 있다. 이러한 규제, 선급 규칙 및 인센티브제는 질소산화물, 황산화물 및 입자상물질 배출에 제한을 가하는데, 황산화물 및 입자상물질 배출 제한은 간접적으로 연료유에 함유되어 있는 황 함량 규제를 통하여 하고 있거나 하려고 한다. 여기에 이러한 규제, 선급 규칙 및 인센티브제에서 가하고 있거나 가할 예정인 선박 디젤기관 연료유의 황 함량 규제에 대하여 간략하게 소개한다.

• Economic and Environmental Geology
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• v.17 no.3
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• pp.171-177
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• 1984

Representative sulphide samples from the Sangdong skarn orebody and quartz veins show relatively narrow ranges of sulphur isotope values ranging from $^+5.5$ to $^+6.9$ permil and average $^+5.0$ permil with a standard deviation of 0.77 permil. Much higher temperature isotopic temperatures than homogenization temperatures may indicate even minerals in contact did not form together in isotopic equilibrium. Under conditions of formation of the skarn and quartz veins, ${\delta}^{34}\;H_2S$ ranges from $^+4.5$ to $^+5.3$ permil, suggesting a magmatic origin for the sulphur. Carbon and oxygen isotope values seem to show some of the spread of increasing ${\delta}^{13}C$ values of the interbedded limestone with distance from the central zone of the Sangdong mineralization. Negative values of ${\delta}^{13}C$ fluids appear to be typical of many ore deposits including those of magmatic origin. Calculated ${\delta}^{18}C$ values of the fluids are typical of those derived from magmatic sources.