• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.34-37
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• 2002

In this study, electrochemical characteristics variation and removal efficiency with initial pH and mineral compositions during electrokinetic remediation of lead contaminated soils were investigated. Test results showed that heavy metal transportation affected by soil characteristics and electrochemical characteristics varied during electrokinetic remediation. Therefore, in the application of enhanced electrokinetic remediation technique to increase removal efficiency, discrete selection of enhanced technique with characteristics of targeted soil were needed.

• 한국윤활학회:학술대회논문집
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• 한국윤활학회 2002년도 proceedings of the second asia international conference on tribology
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• pp.351-352
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• 2002

In this paper, studies were made on the palm oil methyl ester (POME) added lubricants using FT-IR for monitoring oil degradation. In order to assess the degradation characteristics of POME added lubricant by FT-IR, static oxidation test was conducted using three different blended lubricants (viz, zero percent POME, five percent POME and ten percent POME with mineral-based oil) for 280 hrs. The oxidation temperature was set at $140^{\circ}C$. FT-IR quantitative data indicate an increased in oxidation products which was formed from 10% POME added lubricants after 280 hrs of oxidation test. The 5% POME added lubricant and mineral-based lubricant (without POME) showed less oxidation product after the test. From the FT-IR spectrum analysis of the oxidized oils it could be concluded that 5% POME can improve the performance of mineral-based oil by forming protective films.

• 한국인쇄학회지
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• 제30권3호
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• pp.13-21
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• 2012

This study was carried out to evaluate the stability of archival documents produced using papers. The properties of archival documents depend on the type of fillers of papers that are used such as fiber, non cellulose fiber, and mineral. The physio-chemical characteristics of archival documents were analyzed by employing acid hydrolysis against cellulose fiber substances. Fibers of Korean hand-made (Hanji), flex, and cotten papers showed higher pH and the degree of polymerization (DP) than wood fiber and mechanical fiber. Mechanical pulp containing 12.8% of lignin showed the greatest decrease of DP due to acid hydrolysis, and this resulted in increase of degree of aging. The filler found to clay and talc did not contain metal such as $Fe^{+2}$, $Fe^{+3}$, and $Cu^{+2}$. The alkaline metals such as Mg, Ca, and Ti showed greater resistance to acid hydrolysis.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1998년도 봄 학술발표회논문집(II)
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• pp.641-646
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• 1998

The structures exposed to marine environment do not show long-term durability due to corrosion of steel and deterioration of concrete by the attack of various salts dissolved in sea water. In this study, Partial substitution of cement with fly ash(20%) or blast furnace slag(40%) was made together with the addition of 4 different corrosion-inhibitors, as a protective measure of concrete structures against chemical attack of salts. Combined effects of mineral and corrosion-inhibiting admixtures were tested by measuring the resistance and compressive strength of concretes under the simulated tidal condition, which consists of alternating 12 hour periods of immersion in artificial sea water and drying in air. Both the strength and concrete resistance were found to decrease in following order, regardless of the corrosion inhibitors the concretes with blast furnace slag, those with fly ash and those without any mineral admixtures. The interrelation between compressive strength of concrete and resistance was investigated.

• 한국환경보건학회지
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• 제19권2호
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• pp.34-39
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• 1993

One hundred and eighty-seven water samples were collected from 23 of spring water, 2 of ground water, 1 of tap water in Pusan area and 3 of natural mineral waters. Total coliform group, fecal coliform, viable cell count and microflora were investigated to evaluate water quality of drinking water. The results were as follows: range and geometric mean value of total coliform and fecal coliform MPN's of spring water were 0~1,500/100 ml, 85/100 ml and 0~460/100 ml, 24/100 ml but coliform group was not detected in the samples of tap water and natural mineral water. Viable cell count of spring water, ground water and tap water were lower as 100 cell than the criteria for drinking water but that of natural mineral water was higher as 6.5X 10$^2$~7.4X 10$^3$ /ml. Predominant speces among the 219 strains isolated from the samples were 19.6% Aeromonas spp., 19.2% Enterobacteriaceae, 16% Acinetobacter spp. Especially, spring water and vessels were contaminated by Hafnia spp. and Providencia Spp, inhabitant of the oral cavity.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.202-208
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• 2001

Aluminum dross should be recycled in consideration of characteristics of the dross and its reutilization after processing. In this study, aluminum dross generated in the domestic secondary aluminum industry was processed to use it as raw material for producing aluminum hydroxide. Sample dross was classified according to its size. The dross smaller than 1mm was leached with sodium hydroxide solution to extract the remaining aluminum from the dross into the solution, and then aluminum hydroxide precipitate was recovered from the leach liquor. Purity of the obtained aluminum hydroxide was above 98 percent, and particle size of the sample was in range of 3-39${\mu}{\textrm}{m}$. From the result, it was suggested that this process could be applicable to recycling of aluminum dross.

• 에너지공학
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• 제27권1호
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• pp.59-64
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• 2018

In this paper, we investigated the alternative sources of limestone. Oyster shell waste originated from aquaculture that causes a major disposal landfill problem in coastal sectors in southeast Korea. Their inadequate disposal causes a significant environmental problems araised. Bio mineralization leads to the formation of oyster shells and consists $CaCO_3$ as a major phase with a small amount of organic matter. It is a good alternative material source instead of natural lime stone. The utilization of oyster shell waste for industrial applications instead of natural limestone is major advantage for conservation of natural limestone. The present work describes the limestone and oyster shells hydraulic activity and chemical composition and characteristics are most similar for utilization of oyster shell waste instead of natural limestone.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.302-311
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• 2008

There have been repetitive landslides and debris flows on natural terrain induced by intensive rainfalls which have never been experienced during the last a few decades in Korea. Frequencies and magnitudes of landslides and debris flows are steeply increased after 2000 resulting in huge damages of human beings and facilities. According to a statistical data from NEMA, the human deaths induced by landslides and slope hazards occupies 22.3% of the total human deaths by all the natural hazards in Korea during the last 30 years. Among the human deaths by landslides and slope hazards, 85% of the damages were caused by landslides and debris flows on natural hazards. Therefore, this paper summarizes important events of landslides and debris flows, their characteristics, and suggests some methods of damage mitigation.

• Computers and Concrete
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• 제7권1호
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• pp.17-38
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• 2010

This research aimed to investigate the influence of high-volume mineral admixtures (MAs), i.e., fly ash and slag, on the hydration characteristics and microstructures of cement pastes. Degree of cement hydration was quantified by the loss-on-ignition technique and degree of pozzolanic reaction was determined by a selective dissolution method. The influence of MAs on the pore structure of paste was measured by mercury intrusion porosimetry. The results showed that the hydration properties of the blended pastes were a function of water to binder ratio, cement replacement level by MAs, and curing age. Pastes containing fly ash exhibited strongly reduced early strength, especially for mix with 45% fly ash. Moreover, at a similar cement replacement level, slag incorporated cement paste showed higher degrees of cement hydration and pozzolanic reaction than that of fly ash incorporated cement paste. Thus, the present study demonstrates that high substitution rates of slag for cement result in better effects on the short- and long-term hydration properties of cement pastes.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2013년도 추계 학술논문 발표대회
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• pp.156-157
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• 2013

As the chemical shrinkage and autogenous shrinkage of paste constitutes a large part of the shrinkage of high strength concrete, a good understanding of characteristics of chemical shrinkage and autogenous shrinkage is essential in order to understand chemical shrinkage and autogenous shrinkage of concrete. In this study, a preliminary study on effect of mineral admixture on chemical shrinkage and autogenous shrinkage of paste was compared.