• 대한치과기공학회지
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• 제29권1호
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• pp.121-131
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• 2007

A preparation process's conditions of aqueous sol which contains anatase-type nano titania particles with photocatalyic properties was established by using Yoldas process, so called, DCS(Destabilization of Colloidal Solution) process in this study. And crystal size change and phase transformation of titania particles in aqueous titania sol depending on reaction conditions was investigated by a light scattering method and XRD analysis of frozen dried powders, respectively. This sol with photo catalytic nano titania particles was used to the following hydrophilic hybrid coating film's fabrication and its properties was evaluated. Subsequently, for coating film using the above mentioned aqueous titania sol, non-aqueous titania sol was prepared without any chemical additives and its time stability according to aging time was investigate. By using the above mentioned aqueous titania sol and non-aqueous sol, a complex oxide coating sol for metal and ceramic substrate and a organic-inorganic hybrid coating sol for polymer substrate was prepared and it's hydrophilicity depending on UV irradiation conditions was evaluated. As a conclusions, the following results were obtained. (1)Aqueous titania sol The average particle size of titania in formed aqueous titania sol was distributed between 20$\sim$90nm range depending on reaction conditions. And the crystal phase of titania powders obtained by frozen drying method was changed from amorphous state to anatase and subsequently transformed to rutile crystal phase and it is attributed to concentration gradient in aqueous sol. (2)Non-aqueous titania sol Non-aqueous titania sol was prepared using methanol as a solvent and a little distilled water for hydrolysis and nitric acid as a catalyst were used. The obtained non-aqueous titania sol was stable at room temperature for 20 days. Additionally, non-aqueous titania sol with addition of chealating reagent such as acethylaceton and ethylene glycol prolonged the stability of sol by six months. (3)Complex sol and hybrid sol with super hydrophilicity The above mentioned aqueous titania sol as a main photocataylic component and non-aqueous titania sol as a binder for coating process was used to prepare a complex sol used for metal, ceramic and wood material substrate and also to prepare the organic-inorganic hybrid sol for polymer substrate such as polycarbonate and polyethylene, in which process APMS(3-Aminopropyltrimethoxysilane), GPTS(3-Glycidoxypropyl-trimethoxysilane) as a hydrophilic silane compound and HEMA(2-Hydroxyethyl methacrylate) as a forming network in hybrid coating film were used. The hybrid coating film such as prepared through this process showed a superhydrophilicity below 1$10^{\circ}$ depending on processing conditions and a pencil's hardness over 6 H.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.215-225
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• 2006

Today's requirements for print-press runnability and print quality demand an optimised absorption and adhesion of printing ink on the paper surface. Modern coating concepts for high glossing offset grades use ultra fine pigments, whereas binder level has continuously been decreased to a minimum in recent years to achieve the highest possible sheet gloss development and for economical reasons. Both the ultra fine pigments and the reduced binder levels lead in many cases to a faster ink setting rate. On the other hand, matt paper grades use relatively coarse pigments leading to a slow ink setting compared to the high glossing papers. Both too fast and too slow ink setting properties implicate drawbacks in print quality and print press runnability. The mechanisms behind the interactions between ink and coating have been presented in many previous publications. The purpose of this study was to determine and quantify how the ink setting rate is influenced by pigment system (GCC and GCC/clay blends), latex level and latex properties in the topcoat of double coated sheet fed offset paper. The roles of binder level and type in the precoat were also assessed. The effect of calendering (temperature and pressure) was studied with one formulation. The resulting ink setting characteristics were tested using three different laboratory testing instruments. The correlation amongst the different laboratory testing methods is discussed. The results show that by varying the latex properties, the pigment system and/or latex addition level, the ink tack development of ink applied to a topcoat pigment system can be significantly influenced. It can be slowed down as often desired with ultra fine pigments or speeded up in the case of coarse pigments. There was no visible effect on the ink setting rate by using different binder systems in the precoat..

• Journal of the Korean Wood Science and Technology
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• 제42권1호
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• pp.49-57
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• 2014

최종함수율은 예비천연건조를 수행한 시험재에서 더 균일하게 건조가 가능하였으며, 예비천연건조 후 고온저습건조시 최종함수율은 초기함수율에 영향을 받는 것으로 사료된다. 재면할렬 억제 효과는 예비천연건조를 수행한 시험재에서 더 효과적인 것으로 조사되었으나, 예비천연건조 중 발생된 재면할렬에 의한 영향이 크기 때문에 예비천연건조 중할렬발생 억제가 중요할 것으로 판단된다. 부분엔드코팅은 내부할렬, 표면경화율, 비틀림, 수축율에 미치는 영향이 없는 것으로 조사되었다. 예비천연건조는 고온저습건조 중 내층에 발생하는 인장응력을 감소시켜 내부할렬의 발생을 매우 효과적으로 억제하고 표면경화율을 감소시키는 것으로 조사되었다. 비틀림의 경우 함수율감소에 따른 수축으로 인하여 비틀림의 정도가 증가되었다.

• 펄프종이기술
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• 제40권2호
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• pp.23-28
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• 2008

As well as crop cultivation, they could not avoid automatizing and using more environmental friendly process in cultivation of fruit. And also, the consumer ask more safe fruit which is produced with more clean method. This is why the usage of aid materials for fruit cultivation like as fruiting bags are increasing. Practical utilization of wax emulsion treated water repelling fruiting bags are developed continuously and it's properties is compared properties of nomal fruiting bags. The water repelling process was developed with wax emulsion coating. After the experiment of wax emulsion preparation from paraffin and DEA and/or OA in Lab. scale, the wax emulsion was manufactured on pilot scale. The wax emulsion coated paper was prepared in mill scale coater. The water repellency and properties of emulsion coated fruiting bags were evaluated and compared with that of current fruiting bags.

• Journal of the Korean Wood Science and Technology
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• 제25권1호
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• pp.65-70
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• 1997

The effects on the enzymatic hydrolysis of waste paper treated with physical or chemical treatment were investigated. To gain the higher saccharification rate, physical or chemical treatment are necessary in enzymatic conversion process of waste paper. The major deterrents to the effective utilization of waste paper for enzymatic conversion process are phenolic compounds, cellulose crystallinity and coating materials. In the enzymatic hydrolysis of waste paper, the deterrents through enzymatic conversion process can be eliminated by the physical or chemical treatment. This study was performed to obtain the optimal condition for enzymatic conversion process of non-treated waste paper and to review effects on enzymatic conversion process of waste paper treated with physical or chemical methods. In the aspect of saccharification rate, waste paper treated with 1.5% sodium hypochlorite was the most effective and in physical treatment methods, multi-stage treatment(autohydrolysis+refining treatment) was more effective than the other physical treatment.

• 펄프종이기술
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• 제32권3호
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• pp.39-47
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• 2000

This study was carried out to investigate the effect of the type of base papers containing Sw-BDP, HW-BDP and Bamboo-BKP on the properties and printabilities of coated papers. Also it was intended to evaluate the effect of coated paper prepared with anionic and amphoteric latex based coating color. The results obtained from this study were as follows. The fiber length of Bamboo-BKP was observed longer than that of the Hw-BKP and shorter than that of the Sw-BKP. This has effect on physical properties. Therfore the results of mea-suring physical properties were higher ratio of Sw-BKP physical properties tended to be slightly higher with the increase I the mixing ratio. Considering the optical properties of base papers the highest opacity was obtained in case of the Hw-BKP and the second appeared Bamboo-BKP. On the other hand smoothness roughness and air permeability of Bamboo-BKP were lower than those of wood pulp and the optical properties of coated papers tended to show the similar with those of base papers. The ink receptivity and print gloss of the coated papers for Bamboo-BKP were lower than those of wood pulp. As the mixing ratio of Sw-BKP was increased the properties and printabilities were improved slightly. Meanwhile amphoteric latex was improved the optical properties and printability of coated papers.

• 펄프종이기술
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• 제46권4호
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• pp.44-53
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• 2014

This research were aimed at developing starches which have high preservability and high bonding strength from corn starch, modified cationic and oxidized corn starches, as compared to the fermented wheat starch. On the lining that attaching the base paper on the back of the work with paste, the coating weight was determined by the solid contents of the paste rather than the viscosity of paste. Adhesive strength and stiffness were also determined by the solid contents of the paste. Corn starch had lower solid contents, higher viscosity, and higher adhesive strength than other starches. In the iodine stain to the surface of peeled base paper off, paste deeply penetrated into the traditional Hanji than modern Hanji. And oxidized starch paste deeply penetrated into the paper layer than the cationic starch.

• 박물관보존과학
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• 제5권
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• pp.37-41
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• 2004

광주신창동 저습지유적에서 출토된 수침고목재 유물은 재질이 매우 취약하여, 공기 중에 노출되면 건조가 진행되어 곧바로 수축·변형이 일어나게 되므로 전시 및 보존을 위해서는 특별한 보존처리가 필요하다. 특히 칠기칼집과 같이 목재표면에 치밀하게 옻칠이 되어있어 칠기는 처리약제가 잘 침투되지 않고 처리 중 칠막이 부풀거나 탈락될 우려가 높아 보존처리가 매우 까다롭다. 칠기칼집은 낮은 농도의 PEG#4000 40% 수용액(水溶液)에 함침처리 후 동결건조하는 방법을 적용하여 보존처리 하였다.

• 박물관보존과학
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• 제7권
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• pp.43-51
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• 2006

광주 신창동 저습지유적에서 다양한 목재유물과 더불어 목재표면에 옻칠이 된 칠기들이 다량으로 출토되었다. 칠기들은 목질부가 열화 되어 취약하며 칠층이 들떠있어 박락과 갈라짐의 발생우려가 높다. 따라서 진공 동결건조에 효과적인 PEG#4000 40%로 함침처리 하였고 동결건조의 종료온도를 0℃이하로 하였다. 동결건조 직후 목제와 칠기의 중량과 상대습도 60% 의 밀폐공간에서 방치 후 중량을 비교하였다. 그 결과 중량변화가 없었으므로 동결건조 중 종료 온도 조절로써 건조 후 목재함유수분조절과 대기 중 습도변화에 안정성을 확인하였다. 칠도막 분석결과 밑층에 흑색안료를 혼합하여 목재표면에 밑칠을 하고 칠층의 상부에 옻칠과 흑색안료를 혼합하여 3~4회 칠한 것과 검은 밑칠을 하지 않고 칠층에 옻칠과 흑색 안료를 혼합하여 3~4회 칠한 것으로 확인되었다.

• 한국주거학회논문집
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• 제16권2호
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• pp.1-10
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• 2005

The purpose of this study is providing useful information for consumer-friendly house plan by investigating remodeling apartments according to the area type and size. In order to achieve this aim, case study was applied. The case study was conducted of five small, medium, and large size apartments through depth-interviews, actual survey, and questionnaires on the remodeling behavior, interior design, and interior atmosphere. The results of the study are as follows: Structural alterations were frequent in communal area, and then in private and household areas. Changing lighting fixtures was frequent in all area types, and especially, in communal areas installing extra decoration was frequently observed. Besides, alterations of doors and window frames were carried out in communal, private, housework and service areas by using wood, aluminum sashes, double-glazing, and paint coating. Finally, in housework areas the material and color of counters were changed into wooden and achromatic.