• 한국환경과학회지
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• 제11권5호
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• pp.445-454
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• 2002

Material exposure experiments were performed to evaluate the relationship between air pollution and material corrosion rates based on collaboration with researchers in China, Japan, and Korea. Qualitative and quantitative atmospheric corrosion was estimated from damage caused to bronze, copper, steel, marble, cedar, cypress, and lacquer plates exposed to outdoor and indoor conditions in certain East Asian cities. The effects of atmospheric and meteorological factors on the damage to the copper plates and marble pieces were estimated using a regression analysis. The results indicated that sulfur dioxide produced the most destruction of the materials, especially in South Korea and China. In Japan, the copper plates were damaged as a result of natural conditions and sea salt. Copper was also found to be damaged by the surface deposition of sulfur and chlorine. Meanwhile, marble was substantially degraded by gaseous sulfur dioxide, yet sulfate ions in rain had no effect. Accordingly, the analysis of air pollution from the perspective of material damage was determined to be very useful in evaluating and substantiating the intensity of air pollution in East Asia.

• 보존과학회지
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• 제36권5호
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• pp.368-382
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• 2020

백자 철화 인물형 명기는 전시 후 철수하는 과정에서 염 손상이 확인되었다. 이 연구에서는 유물의 보존방안을 마련하기 위해 염 손상 상태를 분석하고 재질 특성과 전시환경을 검토하여 손상 메커니즘을 파악하였다. 명기 표면에 결정화된 탄산염(Na₂CO₃)은 수용성 알칼리염으로 흡습성이 높고 물에 잘 용해되며 온도가 상승할수록 용해도가 증가한다. 재질 분석 결과, 명기는 1000℃ 부근에서 소성된 저화도 백자로 연유(鉛釉)가 시유되었고 유약 면에는 빙렬이 있어 표면 물성이 취약한 상태였다. 전시환경 분석 결과, 공조기 가동에 따라 환경제어가 되는 전시실에 비해 진열장 내부는 온·습도가 높은 환경에 노출되면서 결로 등 수분환경 조성이 예측되었다. 또한 공조기 가동과 중단에 따른 급격한 온·습도 변화에 노출된 것을 확인하였다. 이를 통해 명기 내 잔류한 수용성 염이 온도 변화에 따라 상대적으로 취약한 부위인 유약층 표면 쪽으로 이동하고, 건조환경에서 수분이 증발함에 따라 염의 결정화 압력 작용하여 표면 손상이 가중된 것으로 판단된다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2004년도 춘계 학술발표회 제16권1호
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• pp.184-187
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• 2004

There are many factors that generate the early deterioration of the concrete structure. As the one of the representative factors, we can think an invasion of the water, air and so on. The water and air invade in inside void along the capillarity and they become the cause that the durability like corrosion of layer department due to freezing and thawing, inside steel frame corrosion, and so on blacks. Therefore with covering permeability covering waterproofing material of fluid condition in outer wall, intercepting the deterioration factor due to the infiltration of water from outside and for salt damage of concrete layer department, freezing damage and neutralization, it needs to improve durability of structure. This study separately examined physical and chemical specific of quality liguid siliceous of waterproofing material. Therefore as this applys the construction site, it improves the durability of concrete structure. Further this presents the application plan from the construction market against the new material.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.139.1-146
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• 2001

Contact lines are necessary to supply electric locomotives with electric power. As most railways are gradually electrified with modernized electric cars, the demand for catenary wires and their facilities are also increased. Catenary wires made by metallic materials are generally used in the open air. They are exposed to the marine area with air-borne salt or severely polluted industrial area with much corrosive emission gases depending on the railway locations. In urban area, acid rain may cause a degradation of catenary wire system. Corrosion of catenary wires can make their actual lifetime shorter than that originally designed. Thus, the messenger wires, a kind of catenary wire system, were investigated with respect to corrosion, which include new and the used one collected at the field. They are also vibrated with some amplitude everytime the train passes through the railway. The frequent cyclic load on the wire any result in a fatigue damage, Surface damage by corrosion can make fatigue crack initiate with ease. In the present study, the fatigue life of the used wire was measured 40 to 50% shorter than that of new one in average.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문 발표회
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• pp.63-67
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• 2003

There are many factors that generate the early deterioration of the concrete structure. As the one of the representative factors, we can think an invasion of the water, air and so on. The water and air invade in inside void along the capillarity and they become the cause that the durability like corrosion of layer department due to freezing and thawing, inside steel frame corrosion, and so on blacks. Therefore with covering permeability covering waterproofing material of fluid condition in outer wall, intercepting the deterioration factor due to the infiltration of water from outside and for salt damage of concrete layer department, freezing damage and neutralization, it needs, to improve durability of structure. This study separately examined physical and chemical specific of quality liguid siliceous of waterproofing material. Therefore as this applys the construction site, it improves the durability of concrete structure. Further this presents the application plan from the construction market against the new material.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2003년도 학술.기술논문발표회
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• pp.63-67
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• 2003

There are many factors that generate the early deterioration of the concrete structure. As the one of the representative factors, we can think an invasion of the water, air and so on. The water and air invade in inside void along the capillarity and they become the cause that the durability like corrosion of layer department due to freezing and thawing, inside steel frame corrosion, and so on blacks. Therefore with covering permeability covering waterproofing material of fluid condition in outer wall, intercepting the deterioration factor due to the infiltration of water from outside and for salt damage of concrete layer department, freezing damage and neutralization, it needs to improve durability of structure. This study separately examined physical and chemical specific of quality liquid siliceous of waterproofing material. Therefore as this applys the construction site, it improves the durability of concrete structure. Further this presents the application plan from the construction market against the new material.

• 한국구조물진단유지관리공학회 논문집
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• 제10권1호
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• pp.123-130
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• 2006

콘크리트의 열화 및 철근부식에 대응하기 위하여 다양한 보수재료가 존재하나 이러한 보수재료를 평가하는 방법은 단순히 염해, 중성화 등의 단독열화만을 대상으로 하고 있어 여러 가지 열화인자가 복합적으로 작용하는 실제 환경과는 차이를 나타내게 된다. 따라서 본 연구에서는 폴리머시멘트계 보수용 단면복구재가 KS 기준을 만족하는지 확인한 후 복합열화 환경 하에서 염해, 중성화. 철근부식을 평가하였다. 실험결과 각각의 보수재료들은 KS 기준을 만족하였지만 내구성능은 상이하게 나타나 향후 이에 대한 고려가 필요할 것으로 사료된다.

• 보존과학회지
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• 제12권1호
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• pp.15-25
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• 2003

석조물에 있는 염들이 암석의 손상에 영향을 끼친다는 것은 잘 알려져 있다. 석조물 표면에 형성된 흑색층에서는 다양한 염이 다량 검출되고 있어 흑색층 내에서의 염의 역할과 또 그 기원에 대한 고찰이 요구되고 있다. 이 논문에서는 독일 베를린에 소재한 역사적인 건물에 사용된 사암과 석회암을 대상으로 염들의 특성을 알아보았다. 염은 원자 흡광분석기와 원자발광분석기 및 이온크로마토그래피를 이용하여 분석하였다. 모든 흑색층에서 가장 대표적인 이온은 $Ca^{2+}$과 $SO_4^{2-}$으로, 통계처리에 따른 형성 가능한 염은 황산칼슘이다. 흑색층의 X-선 회절 분석법에서 석고$(CaSO_4{\cdot}2H_2O)$가 검출되었으므로, 여기에 형성된 황산염은 이수화물 형태임을 알 수 있다. 칼슘의 기원이 사암 흑색층에서는 대기중의 먼지로, 석회암 흑색층에서는 모암인 것으로 추정되며, 황은 대기 오염물과 보수 시 사용된 모르타르에서 기인한 것으로 보인다.

• 패션비즈니스
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• 제13권3호
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• pp.136-148
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• 2009

The phenomenon of the shrinkage of silk fibers induced by inorganic salts including LiBr, $Ca(NO_3){_2}$, and $CaCl_2$, has been studied up to the present as one of the finishing methods of silk. It is expected that the shrinkage phenomenon may greatly contribute to the realization of the high sensibility of silk fibers. Especially the shrinkage enables the expression of three-dimensional appearance of silk fabrics along with the improvements in dimensional stability, resilience in stretching, and comfort. Numerous theoretical studies on the contraction phenomenon by $Ca(NO_3){_2}$ have been conducted so far. These studies have focused mostly on the silk fibers. It is difficult to find studies on silk fabrics. The negative aspects of the finishing are such as strength drop, yellowish discoloration, and fiber damage. These should also be considered as well as the positive aspects. In this study, the phenomenon of salt shrinkage is diversely reviewed by applying $Ca(NO_3){_2}$ solution for the silk fabrics as objects. The changes in the air permeability, thickness, and color were investigated with focus on the shrinkage of the silk fabrics according to the changes in treatment conditions. Some findings from this study are as follows: Within short period of time at the initiation of salt shrinkage, the salt shrinkage proceeds effectively. In the case of concentration of 47.4%, or 46.3% of $Ca(NO_3){_2}$ solution, appropriate treatment time seems to be 20seconds, or $2{\sim}8$minutes, respectively. Excessive shrinkage is obtained when lower liquor ratio is adopted. As a result, the condition is acting extremely disadvantageously against the thickness and yellow discoloration aspects.

• 한국구조물진단유지관리공학회 논문집
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• 제7권2호
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• pp.141-148
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• 2003

Concrete surface is a part that resists chiefly to carbonation by carbonic acid gas, affluence of rainwater and air, deterioration by freezing thawing, salt damage by seawater, and other chemical erosion etc. Therefore, this research analyzed physical characteristic and durable characteristic of concrete eliminated glut water and bubble of concrete surface using CON-SILK that is permeated with dehydration. As a research result, concrete using CON-SILK was improved, in comparison with concrete using general formwork, in physical performance and durability of concrete, as surface hardness, carbonation resistivity, and salt content permeation resistivity etc. Therefore, we could know that it is effective to use CON-SILK in performance elevation of concrete surface.