• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2238-2246
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• 2012

Molecular dynamics simulations have been performed to investigate hydrogen bonding characteristics of hydroxyl groups in glucose aqueous solutions with different concentrations. The hydrogen bonding abilities and strength of different O and H atom types have been calculated and compared. The acceptor/donor efficiencies have been predicted and it has been found that: (1) O2-HO2 and O3-HO3 are more efficient intramolecular hydrogen bonding acceptors than donors; (2) O1-HO1, O4-HO4 and O6-HO6 are more efficient intramolecular hydrogen bonding donors than acceptors; (5) O1-HO1 and O6-HO6 are more efficient intermolecular hydrogen bonding acceptors than donors while hydroxyl groups O2-HO2 and O4-HO4 are more efficient intermolecular hydrogen bonding donors than acceptors. The hydrogen bonding abilities of hydroxyl groups revealed that: (1) the hydrogen bonding ability of OH2-$H_w$ is larger than that of hydroxyl groups in glucose; (2) among the hydroxyl groups in glucose, the hydrogen bonding ability of O6-HO6 is the largest and the hydrogen bonding ability of O4-HO4 is the smallest; (3) the intermolecular hydrogen bonding ability of O6-HO6 is the largest; (4) the order for intramolecular hydrogen bonding abilities (from large to small) is O2-HO2, O1-HO1, O3-HO3, O6-HO6 and O4-HO4.

• 폴리머
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• 제32권3호
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• pp.213-218
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• 2008

우리나라 전체 문화재중 약 17%에 해당하는 석조문화재는 대부분 옥외에 있고 시간이 지남에 따라 물리적, 화학적, 기계적, 생물학적인 풍화가 진행되고 있어 표면의 색변화, 균열, 부서짐 등이 발생하게 된다. 이러한 풍화현상을 저지하고 지속적인 형태 유지를 위해 적절한 보존처리가 요구된다. 가압과 감압이 가능한 가압용기를 이용하여 저점도의 아크릴계 단량체인 MMA를 암석에 함침시키고 중합하면 암석의 내부 깊숙이 고분자물질을 충진시킬 수 있다. 그에 따라 암석 구성 물질간의 치밀한 결합이 유지되고 발수성 및 내후성 향상이 기대된다. 본 연구에서는 국내산 화강암 2종을 이용하여 처리 후 수분흡수성, 내화학성, 기계적 성질 등의 변화를 통해 석조문화재에 대한 보존처리 방법으로써 의 가능성을 확인하였다.

• 펄프종이기술
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• 제41권3호
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• pp.66-70
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• 2009

Paper cultural heritages usually experienced the chemical and the physical deterioration because of various factors including preservation environment and the property of their materials. General restoration technology for paper cultural heritages is the lining. The application of the lining paper and the lining technology has varied depending on researcher's experiences. Therefore, each lining material and technology must be evaluated to develop a standard guide for preservation and restoration of paper cultural heritages. To date, various analysis techniques using lining paper, in terms of their materials, have been applied to analyses of causes and condition of damages, but it is difficult to develop a standard restoration treatment method of paper cultural heritages because it varies by their material. The Hanf, is made frrr the mulberry, is generally used for the lining in Korea.edt is required that the cr, in terms properties and general properties of Hanf, is used for lining papers, are evaluated to develop a standard guide for their restoration.ed this study, the general properties of several lining papers(Hanf), especially dimensave bility, were evaluated as part of the standardization of lining papers. The result have varied depending on the pulping chemical and the manufacturers. the basis weight, thickness and tensale strength of lining papers is bigger the paper treated by natural ash than the paper treated by sodium carbonate.ed case of formation, folding endurance, and dimensave bility, the paper treated by sodium carbonate showed better properties than those of the paper treated by natural ash.

• 보존과학회지
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• 제27권3호
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• pp.323-332
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• 2011

고흥 길두리 안동고분에서 파편상태로 출토되어 복원이 불가능한 유리구슬 7점에 대해 미세조직관찰과 성분분석을 실시하여 유리유물의 화학조성 및 풍화의 특성을 밝히고자 하였다. 먼저 유리의 풍화상태를 분석한 결과, 표면과 내부 균열부분에 주변 매장환경으로부터 기인한 것으로 추정되는 오염물질이 다량 관찰되고 검출되었다. 또한 Na과 K 등의 알칼리금속 성분이 균열부에서 주로 감소되는 것으로 보아 이 부분에 풍화현상이 집중적으로 일어났음을 알 수 있었다. 화학조성을 통한 특성분류에서는 potash glass group($K_2O-SiO_2$유리군) 2점, soda glass group($Na_2O-SiO_2$유리군) 4점, 알칼리혼합유리군(mixed alkali glass group) 1점으로 확인되었다. 유리의 발색원소를 추정해보면, 청색과 감색 유리는 코발트(Co), 벽색은 철(Fe)과 구리(Cu), 황갈색은 철(Fe)로 추정된다. 이러한 고분출토 유리구슬의 과학적 연구는 향후 4~5C 호남문화권의 교류관계를 밝히는데 중요한 자료로 이용될 것으로 기대된다.

• 헤리티지:역사와 과학
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• 제45권4호
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• pp.114-125
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• 2012

본 연구에서는 풍납토성 동성벽 내부토양을 대상으로 색도색차계, XRD, 입도분석기 등을 이용하여 색도, 입도, 주요화학조성, 광물결정구조 등을 분석하였다. 성벽토양은 황갈색, 회황색의 모래 또는 실트질 모래(SW~SC)로 분류되고, 입도와 화학 광물학적 특성이 유사하며, 도로나 활주로 등의 성토재료로 적합한 특성임이 확인되었다. 색도, 입도, 화학조성, 강열감량의 4인자를 기준으로 비교분석한 결과, 풍납토성이 위치한 지역의 대조군 토양(PNS)은 성벽축조에 사용되지 않았던 것으로 판단한다. 모든 토양은 풍납토성이 위치한 지역과 지질학적으로 유사한 곳에서 채굴되었던 것으로 추정되지만, 성벽 축조 이전에 분포했던 구지표면의 토양과는 다른 특성을 나타내기 때문에, 유적 주변에 대량채굴이 가능했던 토양분포지가 존재할 것으로 추정된다. 향후 성벽 축조재료의 여러 특성들을 비교 분석하면, 성벽 내부토양의 산지, 축조방법, 보수방법 및 시기 등을 보다 종합적으로 이해할 수 있는 계기가 마련될 것으로 기대한다.

• Advances in environmental research
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• 제4권3호
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• pp.155-172
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• 2015

In this study, a complete set of recirculating cooling water system and the required instruments were built in a semi-industrial-scale and a 50 g/h ozone generation plant and a chlorine system were designed for cooling water treatment. Both chlorination and ozonation treatment methods were studied and the results were analyzed during two 45-days periods. The concentrations of ozone and chlorine in recirculating water were constant at 0.1 mg/lit and 0.6 mg/lit, respectively. In ozone treatment, by increasing the concentration cycle to 33%, the total water consumption decreased by 26% while 11.5% higher energy efficiency achieved thanks to a better elimination of bio-films. In case of Carbon Steel, the corrosion rate reached to 0.012 mm/yr and 0.025 mm/yr for the ozonation and chlorination processes, respectively. Furthermore, consumptions of the anti-corrosion and anti-sedimentation materials in the ozone cooling water treatment were reduced about 60% without using any oxidant and non-oxidant biocides. No significant changes in sediment load were seen in ozonation compared to chlorination. The Chemical Oxygen Demand of the blow-down in ozonation method decreased to one-sixth of that in the chlorination method. Moreover, the soluble iron and water turbidity in the ozonation method were reduced by 97.5% and 70%, respectively. Although no anaerobic bacteria were seen in the cooling water at the proper concentration range of ozone and chlorine, the aerobic bacteria in chlorine and ozone treatment methods were 900 and 200 CFU/ml, respectively. The results showed that the payback time for the ozone treatment is about 2.6 years.

• 보존과학회지
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• 제36권5호
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• pp.430-439
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• 2020

본 연구에서는 화협옹주 회곽함에서 출토된 화장품 중 갈색 고체 잔여물이 나타난 화장품을 중점으로 연구를 진행하였다. 이 화장품은 1752년 부장된 회곽함 안의 청화백자합에서 출토되었다. 국립고궁박물관에서는 유물분석과 문헌조사를 진행하였다. 이를 바탕으로 출토화장품의 원재료와 제조법을 추정하여 크림 형태의 화장품재현을 시도하였다. 이후 출토품과 유사한 열화 양상을 확인하기 위하여 고온, 자외선, 이산화탄소 조건에서 열화를 시행하였다. 이에 따른 변화와 화장품으로써의 효과를 확인하고자 과학적 분석과 기능성 평가를 진행하였다. 유지류가 높은 비율로 혼합된 재현품에서는 고온열화가 진행됨에 따라 색차값이 약 32 차이가 나타났고, O-H 결합과 C=C 결합에서 화학적 변화가 발생하여 유지류 산화가 발생한 것을 확인할 수 있었다. 또한, 자외선 열화를 통해서는 pH 값이 노출 시간에 따라 산성화되는 것을 확인할 수 있었다. 재현품의 기능성 평가로 진행한 차폐율은 현대 화장품의 차폐 기준치보다 낮게 나타났다.

• 보존과학회지
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• 제2권2호
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• pp.31-62
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• 1993

Stone -monuments, distributed in this area, have been investigated and studied in geological and conservational points of view. They are seemed to have been mainly built from the Shilla to Koryeo Kingdom, although more systematic studies are needed. The used rocks in these monuments are mainly biotite granite and hornblende-biotite granite of Jurassic age. The rock phases are nearly identical to those which are distributed in the area. The two rock phases are nearly same in the characteristics of minevalogy and texture except the amount of hornblende. However, hornblende-biotite granite characteristically contains aggregates of mafic minerals which are frequently observable in the monuments. They are mainly influenced by chemical weathering due to warm, abundant rainfall, and salty moisture because of being adjacent to the sea. Some cracks are secondarily developed which may be due to strong chemical weathering and influence of sculpturing. For conservation, it must be scientifically considered based on characteristics and kind of rock phase, factors on weathering process, situation and protection.

• 보존과학회지
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• 제37권4호
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• pp.340-356
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• 2021

We have tried the experimental research of lost-wax casting to reconstruct Gilt-Bronze Pensive Bodhisattva; preliminary and reconstruction experiment based on ancient texts. Main object to reconstruct is Korean National Treasure No.83, Gilt-Bronze Pensive Bodhisattva (Maitreya), then we measure alloy ratio and casting method based on the scientific analysis. Other impurities were removed from the base metal components(copper : tin : lead) and their ratio was set to 95.5 : 6.5 : 3 where the ratios for tin and lead were increased by 2.5% each. The piece-mold casting method was used, and piece-mold casting experiments were carried out twice in this study but supplementary research on piece-mold casting was necessary. The microstructure was confirmed to be typical cast microstructure and the component analysis result was similar to that of the prior study. Analysis of the chemical composition is confirmed to copper, tin, lead, and zinc, and the chemical composition of the matrix was 87.8%Cu-7.5%Sn-2.7%Pb-2.1%Zn, and similar to previous experimental research. Also resulted in the detection of small impurity in Zn. Analysis of the mould revealed that the mould was fabricated by adding quartz and organic matter for structural stability, fire resistance, and air permeability. We expect that our research will contribute to provide base data for advanced researches in future.

• 보존과학연구
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• 통권25호
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• pp.93-117
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• 2004

The stone cultural properties durability is the falling. So the conservation is easy relatively. But the conservation countermeasure of the stone cultural properties the environment pollution needed urgently as extreme. I will find out about the stone cultural properties Through the example of Restoration and conservation treatment about Bowonsabeobin-guksaboseungtap in the paper. Damage reasons of the stone cultural properties are a physical damage, a structural damage, a biology damage, a chemical damage and artificial damage. The moisture plays especially the role which damage is make the stone cultural properties. The stone cultural properties is damaged due to damage reasons. So we investigate the stone cultural properties and must remove damage reasons. Bowonsabeobin-guksaboseungtap is funerary stupa of buddhist monk with circleorientedoctagon in Geryeo Period. There is the open air. Parts of it were damaged by grave robbery in 2004. So restoration was begun in 2004.While restoring it, wrong arrangement on top of the monk-stupa was rearranged. After being arranged in right order, the middle of monk-stupa was fixed by setting up stainlesssteel shaft. A roof stone of stupa finial has cracks. So It was adhered with epoxy resin(L-30) and was washed with distilled water for pollution clearing. The stone cultural properties takes the influence of the environment pollution much because it stays at the fields. It is easy also to be robed. Therefore we must watch more with the concern.