• 한국의류학회지
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• 제33권8호
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• pp.1315-1324
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• 2009

This study is on the consolidation process of the conservation process of fabric with golden thread found in relics. Gold film was glued to pieces of Korean paper and satin using hide glue, which is a natural adhesive and resin Paraloid B-72, which is a liquid type adhesive. This study examines the types and concentration of the adhesives that are appropriate for consolidating gold film on fabric. The advantage of hide glue is that it is harmless to humans and has a high stability. This glue is also believed to be the closest to the adhesive that was used when the relic was originally made. Its weakness is that it is stiff and weaker than chemical glues, but after being washed with water the adhesion level increases. Therefore, hide glue is appropriate in the following instances: a) when washing after consolidation b) when the substrate of gold threads are significantly damaged, and c) when treating greater sized relics that take a longer time to work on. However, Paraloid B-72 has a better adhesion and flexibility than hide glue, but tends to spread out into a greater area, and the area where it is applied tends to absorb less water than before the application. In addition, it is noxious and can be harmful in long-term exposure. Therefore, Paraloid-72 is appropriate in the following instances: a) when consolidating the fabric after washing, and b) when working on smaller relics and consolidating smaller parts of a relic. The necessary concentration levels for consolidants for gold film are 30% for liquid type hide glue and at least 10% for Paraloid B-72 in order for the gold film to stay intact on the fabric during washing, consolidation, exhibition, and conservation.

• 보존과학회지
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• 제37권6호
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• pp.801-806
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• 2021

전통 접착 소재인 아교의 사용성과 해초 추출물 카라기난의 겔화 현상을 개선하기 위해 두 재료를 혼합하여 목재 보존용 액상형 접착제를 제조하였으며, 9종의 천연 및 합성 접착제와의 물성 비교를 통해 적용 가능성을 확인하였다. 제조한 목재 접착제는 15 wt% 아교 수용액과 λ-carrageenan, 항균제, 소포제 등을 혼합하였으며, 1.80 Mpa의 최대 접착 강도를 확인하였다. 비교 결과 5종의 전통 천연 접착 성분(수용액)과 Polyvinyl acetate 기반 접착제 1종보다 우수한 접착 강도가 나타났으며, 총호기성생성균수와 유해성(TVOC, HCHO, 중금속) 시험 결과 불검출로 항균성과 안정성을 확인하였다.

• 보존과학회지
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• 제35권5호
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• pp.480-493
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• 2019

본 논문은 단청 포수 방법 중, 아교수와 교반수처리 방법에 대해 내후성 평가를 하여, 단청의 보존성 향상에 미치는 영향을 분석하였다. 시편은 아교수와 교반수(아교 건조중량의 명반 2%, 5%, 7%)의 점도와 pH 측정을 진행하였으며, 포수층 없음, 아교수 포수층, 교반수 포수층 등 3유형으로 분류 후, 각 저농도(2% 4회), 고농도(10% 1회)로 구분하였다. 이후 바탕층 형성유무에 따라 2차 분류 하여 뇌록·석간주·장단 3종의 가칠 안료를 채색하였다. 완성된 시편은 내후성 평가를 위해 환경변화실험을 진행하였으며, 실험 전·후 표면관찰, 색차변화 등을 분석하였다. 연구결과, 명반 5% 교반수(pH 평균 4.5)와 명반 7% 교반수(pH 평균 4.7)는 강산성에 근접하여 향후 단청의 보존에 영향을 미칠 수 있으며, 명반 7%의 높은 점도는 포수층을 견고하게 만들기 어려울 것으로 판단된다. 또한 자외선 조사 후, 명반 7% 시편에서 황변화가 가장 확연하게 나타났으며 흡습·건조 후, 시편 전체 표면에서 균열이 발견되어 물리적 변화를 확인하였다. 가스부식은 타 실험과 비교 시 색상과 표면상태 변화의 확인이 어려웠다. 결과적으로, 안정적인 포수층의 형성은 중성에 가까운 저농도 아교수와, 명반 2%의 교반수가 적합할 것이며, 명반 2% 교반수의 적용은 단청의 보존에 긍정적일 것으로 파악된다.

• 분석과학
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• 제15권5호
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• pp.475-481
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• 2002

먹는샘물과 용기 중에 phthalate 및 adipate를 분석하였다. 시료 전처리법으로서 먹는샘물의 경우는 methylene chloride를 용매로 하여 액체-액체 추출법을 사용하였고, 고체 시료는 속 슬렛 추출과 실리카겔 정제법을 사용하였다. 추출 후 농축한 다음 GC-MS (SIM)로 정량하였다. 추출물의 chromatogram은 방해물질이 없고 각 피크는 분리가 잘 되었다. 물 시료의 경우 $0.1{\sim}10{\mu}g/L$의 농도범위에서 $r^2$값이 0.996 이상의, 용기시료의 경우 $1{\sim}1,000{\mu}g/Kg$의 농도범위에서 $r^2$값이 0.994이상의 좋은 직선성을 보였다. 물 시료 중에서 검출한계는 $0.002{\sim}0.010{\mu}g/L$의 범위를 용기 시료 중에서는 $0.01{\sim}0.02{\mu}g/Kg$의 범위를 보였다. 먹는샘물 5 종류, PET병 2 종류, 라벨 2 종류, 병뚜껑 2 종류 그리고 접착제 2 종류를 위의 방법에 따라 분석하였다. 그 결과 국내산 먹는샘물 중에서는 대부분 불검출 되었고 외국산 먹는샘물에서 총 프탈레이트 $1.2{\mu}g/L$의 농도가 검출되어 외국의 경우 긴 유통기간 때문에 높은 것으로 판단되나 인체에 유해한 정도의 농도는 아니었다. 용기 재질 분석에서도 국내산 PET 용기에서 (약 0.55 mg/Kg) 보다 외국산의 경우가 (약 1.2 mg/Kg) 비교적 높은 농도로 검출되었다. 한편 라벨이나 접착제에서는 비교적 높은 농도로 프탈레이트가 함유되어 있는 것으로 나타났다. 본 연구결과 먹는샘물과 용기 중에서 프탈레이트의 분석은 공시료 분석값을 정확히 빼주는 것이 필요하며 PET 시료채취 시에는 라벨과 본드를 제외시켜야 정확한 분석값을 구할 수 있는 것으로 나타났다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 춘계학술대회 논문집
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• pp.767-770
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• 2000

A novel process is newly developed for building RP(Rapid Prototyping) parts using a sheet lamination technique. The build process of existing sheet lamination type RP machines consists of the following steps : feeding, lamination and cutting. In this process, the laminated part of an object is often scratched by a cutter or damaged by a laser beam due to the cutting operation preceded by lamination, In addition, decubing of the unused portion from the laminated block is difficult. In the new process, cutting operation is performed before lamination. The cutting operation takes place while a paper sheet is firmly attached on the plate using electrostatic force. Then liquid glue is applied to the calculated region of the given contour for lamination. The process aims to manufacture a $2k RP machine, what we call the Freeform Mater I, that can use A4 or latter-size used papers. A prototype machine that demonstrates the design concept is built and further research issues are discussed.

• Journal of the Korean Wood Science and Technology
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• 제16권3호
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• pp.17-21
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• 1988

In order to investigate the extending effects on urea-formaldehyde resin- or phenol- formal- dehyde resin- glued keruing plywood, hot pressing temperatures were controlled to 110, 140, 170 and $200^{\circ}C$. As the extender, wheat flour, persimmon bark powder, chestnut bark powder, the equivalently- extended with the above three powders, and diatomite powder were respectively mixed with 5, 10, 15 and 20% ratios to the resin liquid, and also with these the no- extended was allowed. Based on the measured bonding strength, the conclusions were drawn: 1. In the urea- formaldehyde resin, extending effects on the bonding strength were in the order of wheat flour, the equivalently- extended with the wheat flour, persimmon- and chestnut bark powder, persimmon bark powder, chestnut bark powder. In the phenol- formaldehyde resin, the effects in the order of wheat flour, persimmon bark powder, diatomite powder, chestnut bark powder were resulted in. Specifically, superior bonding strength to the no-extended were given with the wheat flour and persimmon bark powder. 2. On the whole, the bonding strength decreased gradually, as the hot pressing temperature increased except for the diatomite powder extending.

• Elastomers and Composites
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• 제54권2호
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• pp.123-127
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• 2019

Shrink film is currently being used for plastic container lavels to avoid the use of glue. Polyethylene terephthalate (PET) bottle lavels also use shrink films in the same PET materials for easy recycling of PET bottles. An air layer is generated between the shrink film and PET bottle surface due to the bent shape of the bottle surface. This air layer can insulate external heat, as air has a relatively lower thermal conductivity. In this study, the insulation property of the air layer was examined by computer simulation. Two PET bottle models were used, one with and the other without an air layer between the PET bottle surface and lavel. The two bottle models were filled with cold liquid and exposed to room temperature for 6 h, and the temperatures of the contents were then compared. The results showed that the temperature of the contents in the bottle with the air layer was lower than that without the air layer by at least $2^{\circ}C$. This study suggests an effective lavel design of PET bottles while ensuring that the temperature of the bottle contents is maintained.

• 한국산업보건학회지
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• 제21권3호
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• pp.156-161
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• 2011

Objectives: Tetrahydrofuran (THF) is a colorless, water-miscible organic liquid with low viscosity at standard temperature and pressure. THF has been used as a solvent and a precursor for various syntheses of polymers. However, THF is known to irritate to the eyes, skin and mucus membranes. Overexposure by inhalation, ingestion or skin contact may produce nausea, dizziness, headaches, respiratory irritation and possible skin burns. The purpose of this study is to evaluate of the worker exposure and characteristics of workers in the workplaces that use or manufacture THF. Methods: Sixteen factories in Korea, which manufacture or use THF, were selected for this study and a total of 130 air samples including 104 time-weighted average (TWA) samples and 26 short-term exposure limit (STEL) samples, were collected. Air samples were collected with charcoal tube (100mg/50mg) and analyzed by gas chromatograph/flame ionization detector(GC/FID). Results: The TWA concentration of THF was 16.05ppm (GM) at PS script printing, 2.32ppm (GM) at PVC stabilizer, 1.03ppm (GM) at Lithium triethylborohydride, 0.63ppm (GM) at Polytetramethylene ether glycol(PTMEG), 0.42ppm (GM) at Manufacturing THF, 0.13ppm (GM) at Glue and 0.12ppm (GM) at synthetic rubber/resins. Two out of sampes for PS script printing exceeded 50ppm as 8-hour exposure limit of MOEL. The short term exposure to THF was 54.77ppm (GM) at PS script printing, 17.10ppm (GM) at PTMEG, 13.76ppm (GM) at Manufacturing THF, 2.86ppm (GM) at Lithium triethylborohydride, 0.87ppm (GM) at synthetic rubber/resins and 0.13ppm (GM) Glue. We found that the highest exposure process for both the TWA and STEL samples was PS script process. Two samples exceeded 100ppm as short term exposure limit of Ministry of Employment and Labor(MOEL). Conclusions: Characteristic of STEL concentration for THF is considerably different from TWA concentration in workplaces because workers could exposure high concentration of THF in a moment when they work irregularly schedule. So exposure controls for momentary works have to be prepared, and considered the skin absorption and inhale of THF.

• KSBB Journal
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• 제29권3호
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• pp.183-187
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• 2014

Sick-building syndrome occurs when indoor air is polluted with harmful volatile organic compounds such as formaldehyde which are contained in furniture or new building materials. In this study, formaldehyde-shielding chitosangel sheet was developed and its performance was evaluated. Chitosan and agar were dissolved in acetic acid solution. The optimal concentrations of chitosan, acetic acid and agar were 3, 3, and 2.5 %(w/w). Formaldehyde was spreaded on gypsum board and then wall paper was attached on it by using glue. When chitosan-gel sheet was attached on this control board, the amount of formaldehyde released from the board was decreased by 63% than in control board. On the other hand, decrease in formaldehyde releasing was only 32% when liquid solution of chitosan was spreaded on the control board. This result clearly indicates that chitosan-gel sheet removes formaldehyde more effectively than liqud solution of chitosan. Furthermore, this type of sheet is more applicable to new building than spraying type.

• Tuberculosis and Respiratory Diseases
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• 제64권4호
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• pp.303-308
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• 2008

성인에서 양성 원인에 의한 기관지식도루는 드물며 활동성 결핵이 원인 중 하나로 보고 되었지만 본 증례와 같이 결핵 후유증으로 장기간에 걸쳐서 발생할 수도 있고 만성 흡인과 기침 및 객혈의 원인이 될 수 있으며 활동성 폐결핵으로 오인될 수 있으므로 임상의사들의 주의가 필요하다.