• 보존과학회지
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• 제34권5호
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• pp.397-405
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• 2018

현재 한국 판벽화에 대한 연구는 극히 드물며 정확한 정의, 손상원인 등의 연구 또한 명확히 이루어지지 않고 있다. 따라서 판벽화 및 단청의 채색층 박리부위 고착을 위한 고착처리제의 내후성을 비교하였다. 시료는 육송 위 총 5종의 호분, 자황, 석간주, 뇌록, 삼청안료를 채색하고 아교, 우뭇가사리, Methyl cellulose, PVAc계열 고착제(Caparol binder) 총 4종의 고착제를 각각 농도 0.5%, 1.5%로 도포하여 비교하였다. 고착 보존처리 후 문화재에 발생할 수 있는 환경변화 요소인 온 습도, 자외선을 인위적으로 조사(照射)하였다. 조사 후 환경에 따른 물성 변화는 색차변화, 박리손상도 평가, 표면관찰을 통해 다각적으로 관찰하였다. 실험결과, 아교는 타 고착제들에 비해 모든 채색층이 안정적으로 고착되었으나 실외에 노출되어 있는 삼청에 사용할 시 황변이 우려되었다. 우뭇가사리는 아교와 마찬가지로 삼청은 자외선에 의한 영향을 받으나 이외에 급격한 온 습도 변화에는 타 고착제에 비해 고착력이 가장 우수했다. Methyl cellulose는 일정 이상 농도에서 광택에 유의하여야 하며 급격한 온 습도 변화에 비교적 강했으며 PVAc계열 고착제(Caparol binder)는 타 고착제들에 비해 고착성이 현저히 떨어졌다.

• 접착 및 계면
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• 제22권2호
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• pp.31-38
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• 2021

본 연구에서는 polyoxyethylene(10) dodecylphenyl ether와 3-butenoic acid를 사용하여 방향족을 포함한 아크릴계 비이온 반응성 유화제를 합성하였으며, 합성된 비이온 반응성 유화제는 ¹H-NMR과 FT-IR로 구조를 확인하였다. 수성 아크릴 베이스 에멀젼의 제조에서 합성된 방향족을 포함한 비이온 반응성 유화제와 방향족을 포함하지 않은 비이온 반응성 유화제 및 음이온 유화제를 사용하여 고형분, 전환율, 입도분포, 박리강도와 내열유지력의 물성을 확인하였다. 입도분포의 경우 370~698 nm 범위에서 측정되었으며, 박리강도는 평균 1.507~1.802 kg_f/in범위에서 측정되었다. 제조된 베이스 에멀젼의 내열유지력은 0.50~2.00 mm 범위에서 측정되었으며, 특히 합성된 방향족을 포함한 비이온 반응성 유화제를 사용한 경우, 방향족을 포함하지 않는 비이온 반응성 유화제를 사용한 경우보다 내열 유지력이 가장 뛰어남을 확인하였으며, 수성 아크릴 점착제로 유용하게 사용될 수 있을 것으로 판단된다.

• 대한기계학회논문집A
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• 제32권4호
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• pp.354-361
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• 2008

Cold rolled steel sheet for automotive was treated by Ar/$O_2$ atmospheric pressure plasma to improve the adhesive bonding strength. Through the contact angle test and calculation of surface free energy for cold rolled steel sheet, the changes of surface properties were investigated before and after plasma treatment. The contact angle was decreased and surface free energy was increased after plasma treatment. And the change of surface roughness and morphology were observed by AFM(Atomic Force Microscope). The surface roughness of steel sheet was slightly changed. Based on Taguchi method, single lap shear test was performed to investigate the effect of experimental parameter such as plasma power, treatment time and flow rate of $O_2$ gas. Results shows that the bonding strength of steel sheet treated in Ar/$O_2$ atmospheric pressure plasma was improved about 20% compared with untreated sheet.

• Journal of Pharmaceutical Investigation
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• 제27권2호
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• pp.133-137
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• 1997

Buccal absorption test of omeprazole in human was performed to determine the permeability of the drug molecule through oral mucous membrane. Oral mucosal adhesive tablets of omeprazole were prepared by compressing the omeprazole with a mixture of sodium alginate and hydroxypropylmethyl cellulose (HPMC) as bioadhesive polymers, magnesium oxide (MgO) as a stabilizer and sodium carboxymethyl cellulose (Na CMC) or cros-carmellose sodium (Ac-Di-Sol) as disintegrants. The bioadhesive force, stability in saliva and release characteristics of the tablets were evaluated. Omeprazole was absorbed about 23% in 15 min through human buccal mucous membrane. Furthermore, omeprazole was stable in saliva for more than 8 hrs when MgO was added to the tablet as the amount of 2.5 fold of omeprazole. The release rate of omeprazole was increased with increasing the amount of sodium alginate in the tablet. From these results, it is suggested that tablets composed of [omeprazole/HPMC/sodium alginate/MgO/Ac-Di-Sol and/or Na CMC (20/6/24/50/10) (mg/tablet)] are potential candidate for buccal drug delivery system.

• 한국산학기술학회논문지
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• 제7권6호
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• pp.1092-1099
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• 2006

본 논문에서는 유도전동기를 인버터와 같은 전력변환장치를 사용하여 정상상태의 동작특성은 물론 과도특성까지 해석하기 위해서는 유도전동기와 부하를 포함하는 전체 시스템의 정확한 동적 모델링을 이용하여 시스템 방정식으로 표현해야 한다. 또한 최대 견인력 제어를 위해서 속도센서리스벡터제어와 부하 토크 외란 관측기를 통하여 점착력 계수를 추정한다. 이와 같은 시스템의 제어 알고리즘을 구현하기 위하여 철도 모의 장치를 이용하여 제안된 알고리즘을 시뮬레이션과 실험을 통하여 확인하고, 철도 차량의 속도 가감에 따른 공전속도에 대한 점착력의 관계 등 제반 사항을 모의 장치에 의해서 구현하였다.

• 한국정밀공학회지
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• 제20권5호
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• pp.189-195
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• 2003

Atomic Force Microscope (AFM) has been widely used in micro/nano-scale studies and applications for. the last few decade. In this work, wear characteristics of silicon-based AFM tip was investigated. AFM tip shape was observed using a high resolution SEM and the wear coefficient was approximately calculated based on Archard's wear equation. It was shown that the wear coefficient of silicon and silicon nitride were in the range of ${10}^{-1}$~${10}^{-3}$ and ${10}^{-3}$~${10}^{-4}$, respectively. Also, the effect of relative humidity and sliding distance on adhesion-induced tip wear was discussed. It was found that the tip wear has more severe for harder test materials. Finally, the probable wear mechanism was analyzed from the adhesive and abrasive interaction point of view.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.346-346
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• 2006

Several types of dynamic atomic force microscopy such as tapping-mode, force modulation-mode are commonly cooperated by phase-contrast imaging techniques, which were interpreted as elastic contrast by mistake in the past and are nowadays regarded as the representation of energy dissipative processes. However, as theoretically reported, the situation is not so simple when the strong adhesive interaction is involved. Furthermore, elastic and viscous contributions are not easily divided in the case of polymeric systems. Thus, the interpretation of image contrast for them must be very carefully treated. In this study, we will demonstrate how such contrast mechanisms are complicated, using several miscible and immiscible polymer blend systems as model samples.

• International Journal of Safety
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• 제5권1호
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• pp.10-16
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• 2006

A suspended hemispherical silicon asperity moving over a silicon plate was simulated. The simulation results on friction and wear in the interface between the two can help obtain more durable miscroscale structures. Silicon structures were constructed with Tersoff three-body potential. Dependence of friction and wear of the asperity on both the atomic arrangement in the plate and the moving direction was investigated under the condition that the asperity is subject to the attractive normal force due to the plate. The results show that the variation of friction force with the movement of asperity, and the occurrence of adhesive wear are attributed to the formation and rupture of asperity, junction between the asperity and the plate. The friction force and wear are smaller when the asperity is incommensurate with the plate, and they also depend on the moving direction of the asperity over the plate.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1988년도 추계학술대회 논문집 학회본부
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• pp.179-182
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• 1988

This study is to investigate the adhesive strength of composite material's interface on the experimental methode of tree growth in the material. The results are as fellows 1) The irradiations of ultrasonic energy cause the mechanical vibration in the polymer composite materials of fluid state, so then bring about physical dispersion and heat form inorganic materials, being supposed to produce chemical crosslinking reaction, decreasing of voids between filler and matrix. 2) The characterics of the breakdown are increased by using coupling agent in the composite material. 3) As the intensity of ultrasonic energy and its irradiated time are larger, the tree inception and break-down voltages increase and the tree growing is slower. so we obtain that the interface adhesive force tan be strengthened by the irradiation of ultrasonic energy.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.813-818
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• 2005

In this paper, a re-adhesion control scheme is proposed for 1C2M propulsion system of TTX. The possibility of slip between wheel and rail in railway system is increasing because of the tendency of high speed and a climatic change. This slip results in the decrease of adhesive effort between this wheel and rail, so the control strategy of traction effort which can reduce the speed promptly and make most use of the maximum adhesive force is absolutely necessary. This paper describes the modeling of the TTX system, and this system is verified by the simulation.