• Journal of the Mineralogical Society of Korea
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• v.27 no.4
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• pp.251-262
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• 2014

Inorganic binders were studied in order to apply a conservation material for stone monument. A pure inorganic binder and 3 species of inorganic binder which contain additives on the basis of a pure inorganic binder were selected as test samples. Through the application of inorganic binders on Geochang granite investigate their influences on stone. pH 4.0 and 5.6 acid solution, respectively were manufactured on the basis of the acidity of domestic rainfall. Alkaline water with pH 8.0 and deionized water with pH 6.85 were prepared as control group. Changes in weights of inorganic binders were not definite according to the acidity of water while weight losses in inorganic binder type were greater after reaction with the water. The compressive strengths of pure inorganic binder was largest before the test but its decrease rate were larger after reaction with the water. Water absorption rate of inorganic binders are 6.72 to $12.44kg/m^2{\cdot}t^{1/2}$ after reaction with the water. Such high absorption was considered that it forced water to move deep into inorganic binder and made the components of inorganic binder dissolve. Acidities of the water of pH 4.0, 5.6, 6.85 and 8.0, respectively were changed to pH 9.0-10.0 after reaction with the inorganic binders. Ion concentrations in the water changed after reaction with the inorganic binders and $Mg^{2+}$, and $K^+$ significantly increased, dissolved from the binder. The high concentration of ions detected showed that the binder reacted with water and formed white salts with high solubility such as $MgSO_4{\cdot}nH_2O$, $KNO_3$. Ion concentrations significantly decreased from the binder after treatment with consolidant and water repellent.

• Restorative Dentistry and Endodontics
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• v.26 no.3
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• pp.191-199
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• 2001

목적 - 기질금속단백분해효소(matrix metalloproteinase)는 조직의 염증 및 치유과정에서 숙주세포에서 생성, 분비되어 세포외기질(extracellular matrix)의 분해에 작용한다. 다양한 염증반응에 기질금속단백분해효소가 중요한 역할을 하는것으로 보고되고 있으나 치수 및 치근단 질환에서의 그 역할은 거의 알려져 있지 않은 상태이다. 본 연구에서는 염증이 있는 사람의 치수 및 치근단 조직을 채취하여 Enzymeimmunoassay 및 면역조직화학적 검색을 통해 제1형, 2형, 3형 기질금속단백분해효소의 수준 및 그 분포를 측정하여 치수 및 치근단 병소에서 이 효소의 작용을 알아보는 것을 목적으로 한다. 방법 - 연구재료는 근관치료를 위해 서울대학교 병원 치과 진료부 보존과에 내원한 환자를 대상으로 34개의 치아에서 통상의 근관치료 중 발수한 치수조직과 치근단 수술중 얻은 치근단 병소(n=10)를 이용하였다. 치수는 발수 전에 임상진단을 통해 급성 치수염(n=12), 만성 치수염(n=12), 정상 치수(n=10)로 구분하고 정상치수로 진단된 것을 대조군으로 설정하였다. 채취된 표본은 둘로 나누어 절반은 30분 이내에 5$\mu\textrm{m}$ 두께로 동결절단을 시행하여 조직표본을 제작하였고 deep freezer에 보관하였다가 헤마톡실린-에오신 염색 및 면역조직화학적 검색을 시행하였다. 나머지 조직은 ELISA를 위해 액체 질소에 보관하였다. ELISA를 시행하기전 표본의 단백질 정량을 시행하여 모든 표본의 단백질 양을 50mg/$\mu\textrm{l}$로 일치시키고 Amersham사의 ELISA kit를 사용하여 제1형, 2형, 3형의 기질금속단백분해효소의 양을 측정하였으며 그 결과를 Mann-Whitney U test를 사용하여 각 군간의 통계학적 유의성을 검증하였다. 결과 1. ELISA의 결과 제1형 기질금속단백분해효소의 농도는 모든 실험군에서 대조군보다 유의성있게 높게 나타났다.(p<.05). 또한 급성치수염군의 제1형 기질금속단백분해효소의 농도가 다른 실험군보다 유의성있게 높았다(p<.05). 2. 제2형 기질금속단백분해효소의 경우 급성치수염군과 대조군에서만 유의성있는 차이를 보였다(p<.05). 3. 제3형 기질금속단백분해효소의 경우 급성치수염군에서 대조군이나 만성치수염군보다 유의성 있는 높은 수치를 보였다(p<.05). 4. 면역조직화학검색 결과 염증성 치수에 존재하는 급성 및 만성염증세포 주위로 기질금속단백분해효소에 대한 면역 반응이 존재하였으며 주로 제1형과 제3형 기질금속단백분해효소의 경우 대식세포 및 림파구 주위로 강한 발색제의 침윤양상이 관찰되었다. 5. 치근단병소의 면역조직화학적 검색 결과 만성염증 세포 주변으로 미약한 발색제의 침윤양상이 관찰되었다.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.3 s.151
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• pp.481-486
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• 2006

There are attempts to utilize Hanji for apparel material, but, the reason that the strength and durability of Hanji decrease to a great extent in the wet condition, restricts the usability of Hanji. In order to improve the resistance against water, Hanji was treated with silicone type water repellent agents. The treatment was carried out by conventional pad-dry-cure method. The optimum treatment condition was obtained by varying the concentration of repellent agent, curing temperature and time. Water repellency was tested by spray rating method. Wet and dry tensile strength, tearing resistance and abrasion resistance were examined after the treatment. Flexural stiffness and wrinkle recovery angles of hanji were also measured. In result, the optimum condition of treatment was at resin concentration of 40g/l, catalyst concentration of 20g/l(half of resin concentration), curing temperature of 160$^{circ}C$, curing time of 120 sec. Flexural stiffness of Hanji was hardly increased and wrinkle recovery angle of Hanji was improved a little by resin treatment. After the treatment, in dry condition, tensile strength and tearing resistance were little changed but abrasion resistance was improved. In wet condition, tensile strength, tearing strength and abrasion resistance were improved.

• Science of Emotion and Sensibility
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• v.14 no.1
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• pp.117-126
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• 2011

This study investigates the physical properties and manufacturing method of shape memory fabric for emotional garment made by polypropylene. For this purpose, polypropylene(PP) POY and SDY were texturized using low temperature and constant length heat treatment texturing technologies, respectively. The shape memory fabrics made using these texturized PP yarns were woven with two kinds of PET and PTT shape memory yarns on the air-jet loom and the various physical properties of four kinds of shape memory fabrics were measured and discussed. The tenacity and breaking strain of PP texturized yarns treated by low temperature and constant length heat treatment showed high weaving efficiency and the wet thermal shrinkage of PP textured yarns was shown less than 1.5%, dry thermal shrinkage was ranged between 3% and 5%, which means thermal stability compared to the PTT textured yarn with high thermal shrinkage, 5~8%. The shape memory characteristics of PP shape memory fabrics measured by Toray method showed five grade as same value as PTT shape memory fabric. The heat keeping property of the PP shape memory fabric showed 56% higher value than that of PTT shape memory fabric. The water repellency of PP shape memory fabric measured by spray method showed five grade as same value as PTT shape memory fabric treated with water repellent agent. Especially, shape memory properties of PP shape memory fabric measured by 3-D image and camera measurement methods showed similar characteristics to the PTT shape memory fabric.

• Journal of the Korea Institute of Building Construction
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• v.14 no.1
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• pp.21-28
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• 2014

The purpose of this study is to investigate the mechanical properties and carbonation resistance of concretes using lightweight aggregate coated surface finishing materials. To evaluate the mechanical properties and carbonation resistance of concrete, slump, air amount, air-dried unit volume weight, compressive strength, and carbonation depth are tested. In terms of the unit volume weight of concrete, air-dried unit volume weight of concrete using coating lightweight aggregate was measured as $1,739{\sim}1,806kg/m^3$. When using coating aggregate, compressive strength of concrete at 28 days was measured as much as 82.7~95.9% of the compressive strength using non-coating aggregate. It is found that compressive strength tends to decrease with coating lightweight aggregate. However, all concretes using coating lightweight aggregate except O-LWAC satisfied the criteria for 28-day compressive strength suggested in KS. The measurement of carbonation depth when the water-repellent agent was used found that carbonation depth was reduced by as much as 2.6~6.1%. On the other hand, when using polymer waterproof agent, carbonation depth was reduced by as much as 8.6~12.0%. Consequently, to improve carbonation resistance, polymer waterproof agent was more effective than water-repellent agent. In particular, epoxy showed the most outstanding performance.

• Journal of the Korea Institute of Building Construction
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• v.13 no.6
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• pp.627-633
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• 2013

This paper presents the result of a mock-up test and field application of concrete that is black in color thanks to the application of superplasticizer containing carbon amino silica black (CASB-SP). Mock-up specimen with a size of $3000{\times}1500{\times}40$ mm was fabricated with black concrete applying 0.5% of CSAB-SP with 27 MPa. After dividing the zone in wall mock-up specimen, three different water repelling agents were applied to verify its effect of efflorescence prevention. It was found that the use of CASB-SP with 0.5% made the black concrete develop a highly clear black color, and the epoxy type water repelling agent had better performance in efflorescence prevention. Based on mock-up test, field application was conducted with bridge member. It was also found that the application of CASB-SP showed favorable results in black color development.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.16 no.4
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• pp.30-37
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• 2002

This paper reports on the results of weathering test, tracking test and salt-fog test of various kinds of cycloaliphatic epoxy systems. UV irradiation dramatically induced the loss of surface hydrophobicity due to the chain scission attack at the surface under UV irradiation. It could be seen that samples containing an UV absorbent/antioxidant and a silicone oil additive have a good performance in weathering test, while ATH(alumina tri-hydrate) filled ones have high resistance against tracking failure than others. Under salt fog chamber test, specimens mixed with silicone oil are able to suppress leakage current development. It was thought that silicone oil mixed into cycloaliphatic epoxy system could lead to lower the surface energy and to retain hydrophobic properties for a long time, which are desirable for outdoor use.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.13 no.3_4
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• pp.89-95
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• 2007

Functional packaging paper containing botanical antimicrobial agent (BAAG) and inorganic zeolite was developed for antimicrobial activity and adsorption of ethylene gas of the paper. The physical properties of the packaging paper showed different characteristics with addition of BAAG and functional fillers: both tensile strength and burst strength were decreased, but both stiffness and tear strength were slightly increased. Zeolite also contributed to fast removal of ethylene gas known as aging hormone of fruits and vegetables. Alkyl ketene dimer (AKD) was greatly effective to endow the packaging paper with water repellency property.

• Journal of Conservation Science
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• v.27 no.4
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• pp.415-420
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• 2011

Urethane coating agent was made up in order to prevent corrosion on metal relics. This urethane coating agent was designed to solve problems linked to gloss and discoloration caused by existing acrylic coating agent which is mainly applied to metal relics. For the purpose, the urethane coating agent was made up which has lower gloss and slight color change. This coating agent formed thinner coating layer with excellent adhesion compared to the existing agent and has outstanding resistance to the surface oxidization of metal relics and water repellent on the surface. In addition, the agent is considered a stable coating agent replacing current acrylic coating agent with showing easy dissolution in organic solvents such as acetone, toluene and xylene with excellent result in reversible reaction.

• Journal of the Korean Applied Science and Technology
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• v.8 no.1
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• pp.9-20
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• 1991

In the preparation of acrylic water repellent(EDLWC). quaternized 2-diethylarrunoethylmethacrylate-stearylmethacrylate copolymer (DSACC) and quaternized 1-Iaurovlbis(aminoethyl)-2-dodecylimidazoline(LDDIC) were selected as a basic resin and the improving agent such as softening effect and hydrostatic pressure of the water repellent. EDLWC was prepared by blending waxes and emulsifier for waxes with various ratio to DSACC and LDDIC. As the results of the measurement of water repellency, washable, tear strength and crease recovery to polyester-cotton(P/C) blended fabrics treated with EDLWC only or addition of textile finishing resin, the physical properties were increased. Sodium acetate was the most effective catalyst in the water repellency among the various kinds of catalyst. and the reasonable concentration of the catalyst was 1. 4 wt%. EDLWC was confirmed as durable water repellent with the results of making little difference of water repellency as ${\pm}5$ point after and before washing. The reaction mechanism between P/C blended fabrics and EDLWC in the presence of catalyst was proposed. And also, the longitudinal view of the P/C blended fabrics treated with water repellent was observed with scanning electron microscope.