• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.203-204
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• 2016

In this research, it used cement power and reduction slag, which generates high hydration heat in hydration reation without heat cure below -5℃ degree. Purpose of final research is preventing freezing and thawing by making the compressive strength 5MPa in 3days below zero temperature due to own heat of concrete. and it is the result of physical characteristic and thermal property evaluation of reduction slag. Because reduction sag generates high hydration heat, compressive strength development is excellent. By generating highly Hydration heat by C₁₂A₇ and C₃A in reduction slag, compressive strength is developed in low temperature. In case of displacing only reduction slag without SO₃, it is indicated that quick-setting occurs by shortage of SO₃. For preventing quick-setting, gypsum is used essentially. According to this research result, in case of using reduction slag and gypsum as a ternary system, Compressive strength developed 5MPa in 3days below zero temperature. It is identified to prevent early frost damage of concrete below zero temperature.

• Fashion & Textile Research Journal
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• v.5 no.3
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• pp.273-282
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• 2003

Effect of fixation methods and relaxation treatment on the flame retardant(FR) and physical properties of MDPP/HMM treated cotton weft-knitted fabrics were studied. Combination of four different fixation methods - relaxation, swelling agent treatment, pad dry cure fixation, and wet fixation - were applied to flame retardant finish of cotton weft-knitted fabric with MDPP/HMM. As the results, 1. Swelling agent and wet fixation method helps FR agent penetrate the fiber efficiently. Interlock showed relatively higher values of LOI than single jersey. 2. Interlock showed relatively higher values of bending rigidity(B), shear rigidity(G) and coefficient of friction(MIU) than those of single jersey before and after flame resistant treatment. 3. An increase in internal volume of cotton fiber by relaxation treatment increased the bending rigidity(B), shear rigidity(G) and compressional energy(WC). 4. The cotton weft-knitted fabric treated wet fixation, which crossliked FR agent efficiently, showed higher bending rigidity, shear rigidity(G) and lower compressional energy(WC). Retention of swelling ability of cotton weft-knitted fabrics treated with MDPP/HMM, which increased the internal volume of cotton weft-knitted fabric, showed lower bending rigidity.

• Textile Coloration and Finishing
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• v.17 no.6 s.85
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• pp.27-35
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• 2005

Conventional pad- dry-cure(thermo-fixation) process usually produces functional performance on both sides of a fabric. UV curing technique was applied to impart water- and oil-repellent finish effective only on the face of a PET knitted fabric. The preferential one-side coating, by virtue of the limited penetration of UV light, was achieved by W curing after padding of a fluorocarbon agent without special coating or printing equipments. The difference in the functional property of face and back sides was examined by measuring water and oil repellency at each side of the treated fabric. The influence of pre/post-irradiation dose and agent concentration on the performance of the finished fabrics were investigated. While increase in both resin concentration and post-irradiation did not have significant effect on the finish, UV pre-irradiation of PET fabrics caused remarkable influence presumably due to appropriate surface modification of PET fabrics required for facile wetting of the resin. The dimensional stability and color change of the UV cured fabrics measured by FAST and reflectance spectrophotometry showed significantly decreased color difference and increased percent extension compared with the samples pre-irradiated without agent application.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.37 no.1
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• pp.56-62
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• 2024

By introducing curing kinetics and chemo-rheology for the epoxy resin formulation for ultra-high voltage gas insulated switchgear (GIS) Insulating Spacers, a study was conducted to simulate the curing behavior, flow and warpage analysis for optimization of the molding process in automatic pressure gelation. The curing rate equation and chemo-rheology equation were set as fixed values for various factors and other physical property values, and the APG molding process conditions were entered into the Moldflow software to perform optimization numerical simulations of the three-phase insulating spacer. Changes in curing shrinkage according to pack pressure were observed under the optimized process conditions. As a result, it was confirmed that the residence time in the solid state was shortened due to the lowest curing reaction when the curing holding pressure was 3 bar, and the occurrence of deformation due to internal residual stress was minimized.

• The Korea Journal of Herbology
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• v.39 no.4
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• pp.11-17
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• 2024

Objective : The purpose of this dissertation is to make a list of the Rhodophyta growing naturally in the Korean coastal waters, and to carry out a survey on the current distribution status to investigate the Bangiaceae which can be used as medicinal herbs. Methods : References and research papers about herbology published at home and abroad were examined. Results : A list was made about Bangiaceae plant which were cultivated or grew naturally in Korea, after investigated the data on domestic and foreign Bangiaceae plants. Out of those lists, serviceable plants were selected , their distributions were analysed. 1. A total of 2 genera and 18 species of Bangiaceae were found in the Korean coastal waters among which 1 genera and 4 species(approximately 22%) were medicinal plants. 2. Out of the 18 species of Bangiaceae 16 species belonged to Porphyra, and out of the 4 species of medicinal plants 4 species belonged to Porphyra. 3. Among the medicinal parts 4 species belonged to algae species had cold property, and had salty and sweet flavors. 4. 4 species had the efficacy of Lung, Spleen and bladder meridian had the potency of soften hardness, which helps to remove hard clots generated, cure phlegm in human body. 5. No toxic drugs were detected. Conclusion : There were totaled to 18 genera and 2 species in Bangiaceae in Korea and among them medicinal plants are 1 genera, 4 species, some 22% in total.

• Journal of the Mineralogical Society of Korea
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• v.12 no.1
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• pp.43-53
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• 1999

The medical mineral menas a single mineral or a complex of minerals. It is natural material. using the medical action of he major or the minor elements, and traditional medicine stuff which has been used since long time ago. Jusa, cinnabar as the mineral name, is the product of the hydrothermal process. It is used to relax the body and cure high blood pressure, apoplexy and cardiopathy. Jusais the major component of "An shin hwan" and "Woo hwang chung shim hwan" nowadays because it has such an excellent calm effect. In addition, it is used to cure cancers such as esophageal cancer and gastric cancer. Jusa composed of mercuric sulfide causes mercury poisoning such as Minamata disease. It is dealt with mineralogical property and chemical composition medical stuff in Korea and China, as well asmercury poisoning and medical action of Jusa in this study. In order to predct accumulation of the interior of the body of the major and minor elements in Jusa, leaching experiment of Jusa by artificial gastric juice was done as well as thermodynamic reaction modelling to know concentration of each species of body fluid. The minor elements of 24 species such as As, Pb, Cd, a and Fe by leaching reaction of Jusa and artificial gastric juice were leached. We can know the fact that as is less than 1 ppm, Hg is less than 25 ppm and Cd and m are not detected. In addition, mercury exists as species of Hg2+, HgCl+, HgCl2, HgCl3-, HgCl42-, HgClOH, HgS(H2S)2, Hg(HS)3-, HgS22-, HgOH and Hg(OH)2 by reaction modelling between Jusa and artificial gastric juice. The concentration of sulfide complexes is 24.2 ppm and that of others is less than 10 ppm. According to increasing pH, the concentration of HgS(H2S)2, Hg(HS)3+, HgS22- and Hg(OH)2 increases, whereas the concentration of HgCl+, HgCl2, HgCl3- and HgCl42- decreases. Therefore, Jusa is very useful for the development of new medicine because it is possible to predict formation of the body species and species accumulation on mercury known as a toxic element and concentration changes of toxicity and efficiency.city and efficiency.

• Macromolecular Research
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• v.17 no.10
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• pp.776-784
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• 2009

N,N-dimethyldodecylamine (tertiary amine)-modified MMT (DDA-MMT) was prepared as an organically modified layered silicate (OLS), after which styrene-butadiene rubber (SBR) nanocomposites reinforced with the OLS were manufactured via the latex method. The layer distance of the OLS and the morphology of the nanocomposites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). By increasing the amount of N,N-dimethyldodecylamine (DDA) up to 2.5 g, the maximum values of torque, tensile strength and wear resistance of the SBR nanocomposites were increased due to the increased dispersion of the silicate layers in the rubber matrix and the increased crosslinking of the SBR nanocomposites by DDA itself. When SBR nanocomposites were manufactured by using the ternary filler system (carbon black/silica/OLS) to improve their dynamic properties as a tire tread compound, the tan $\delta$(at $0^{\circ}C$ and $60^{\circ}C$) property of the compounds was improved by using metal stearates instead of stearic acid. The mechanical properties and wear resistance were increased by direct substitution of calcium stearate for stearic acid because the filler-rubber interaction was increased by the strong ionic effect between the calcium cation and silicates with anionic surface. However, as the amount of calcium stearate was further increased above 0.5 phr, the mechanical properties and wear resistance were degraded due to the lubrication effect of the excessive amount of calcium stearate. Consequently, the SBR/organoclay nanocomposites that used carbon black, silica, and organoclay as their ternary filler system showed excellent dynamic properties, mechanical properties and wear resistance as a tire tread compound for passenger cars when 0.5 phr of calcium stearate was substituted for the conventionally used stearic acid.

• Tribology and Lubricants
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• v.33 no.3
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• pp.92-97
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• 2017

The understanding of the friction characteristics of micro-textured surface is of great importance to enhance the tribological properties of nano- and micro-devices. We fabricate rectangular patterns with submicron-scale structures on a Si wafer surface with various pitches and heights by using a focused ion beam (FIB). In addition, we fabricate tilted rectangular patterns to identify the influence of the tilt angle ($45^{\circ}$ and $135^{\circ}$) on friction behaviour. We perform the friction test using lateral force microscopy (LFM) employing a colloidal probe. We fabricate the colloidal probe by attaching a $10{\pm}1-{\mu}m$-diameter borosilicate glass sphere to a tipless silicon cantilever by using a ultraviolet cure adhesive. The applied normal loads range between 200 nN and 1100 nN and the sliding speed was set to $12{\mu}m/s$. The test results show that the friction behavior varied depending on the pitch, height, and tilt angle of the microstructure. The friction forces were relatively lower for narrower and deeper pitches. The comparison of friction force between the sub-micro-structured surfaces and the original Si surface indicate an improvement of the friction property at a low load range. The current study provides a better understanding of the influence of pitch, height, and tilt angle of the microstructure on their tribological properties, enabling the design of sub-micro- and micro-structured Si surfaces to improve their mechanical durability.

• Textile Coloration and Finishing
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• v.8 no.2
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• pp.25-34
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• 1996

Diphenyl ethanolamidophosphate(DPEAD) was synthesized for the purpose of developing a new flame retardant for cotton fabric. As the intermediate material was used diphenyl chlorophosphate(DPCP) and it was synthesized by using phosphorus oxychloride and phenol as the starting materials. The final product DPEAP was obtained by the reaction of DPCP and ethanolamine. The flame retardancy of cotton fabrics treated by DPEAP through pad-dry-cure(PDC) process was examined at various conditions. The physical property change of the DPEAP treated cotton fabrics were investigated by examining the drape stiffness, the wrinkle recovery, and the tensile strength. The results are summarized as follows: (1) DPEAP has shown excellent flame retardancy on cotton fabrics in comparison to other flame retardants for cotton fabrics available commercially. (2) The optimal condition for PDC process found was that the curing temperature was 16$0^{\circ}C$, the DPEAP concentration was 10%, the catalyst $({NH_{4})_{2}HPO_{4}$ concentration was 7.0%, and the fixing agent hexamethylol melamine (HMM)/DPEAP weight ratio was 1/8. (3) The wrinkle recovery of the processed fabrics increased with increasing DPEAP concentration. (4) The drape stiffness of the cotton fabrics treated by DPEAP have shown essentially no change until increasing DPEAP concentration to 15 %, however DPEAP concentration exceeds 20% the drape stiffness increased drastically with increasing DPEAP concentration. When DPEAP concentration is kept constant the drape stiffness increased with increasing $({NH_{4})_{2}HPO_{4}$ concentration and HMM/DPEAP weight ratio. (5) The tensile strength of the processed fabrics was lower than that of untreated fabrics, but the tensile strength retention increased with increasing DPEAP concentration.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.11 no.9
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• pp.3615-3620
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• 2010

This study is development of UV-cured coating compounds which has more improved anti-stain and anti-biosis, about surface prevention of PVC Tile. We added water-soluble anti-static and anti-microbial agent to the resin. The process has prevented electrostatic and bacterial contagious disease. The result, which added 15wt% of water-soluble anti-static and 1wt% anti-microbial agent and coated with No.12 Bar-coater, coating composition had optimum surface property. It appear electric resistance($10^9{\Omega}/cm^2$), anti-stain (Ink Test, Dust Test), anti-biosis (99.99%), and adhesive power(100%).