• Title/Summary/Keyword: drying degree

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Properties of Bentwood for Esthetic Designing by Microwave and Ammonia Solution Treatment

  • Lee, Won-Hee;Bae, Hyun-Mi
    • Journal of the Korea Furniture Society
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    • v.18 no.4
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    • pp.275-281
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    • 2007
  • This study was carried out to know bending process property of bentwood by treatment methods such as microwave and ammonia solution treatment. Bentwood processing was operated on bending-jig form with 60mm and 100mm radius of curvature (ROC). The species was used to Korean red pine (Pinus densiflora). No significant difference was shown in bentwood processing method on ROC. In treatment method, ammonia solution treatment for bentwood was better in dimensional stability and working ability than that of microwave treatment. However, bentwood stress was reduced with ammonia solution treatment. Color of bentwood surface appearance has a dark tendency in ammonia solution treatment. But it seems to beautiful effect of apparent annual ring is rising esthetically by ammonia solution treatment. To utilize wood as a exterior material for living amenity, it has to be closely examined from various angles including surface property, degree of swelling and shrinkage, drying state, retaining strength, durability, safety, and insect damage.

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An Experimental Study on the Mechanical Properties of High Performance Concrete with Material for Lateral Confinement (횡구속 재료변화에 따른 고성능 콘크리트의 역학적 특성에 관한 실험적 연구)

  • 김은호;정덕우;홍상희;윤기원;한천구
    • Proceedings of the Korea Concrete Institute Conference
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    • 2002.05a
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    • pp.563-568
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    • 2002
  • This paper is a fundamental study on the mechanical properties of the high performance concrete confined with metal lath, glass and carbon fiber laterally. According to the results, it shows that the compressive strength increases by 9%, 8% and 6% in metal lath carbon fiber and glass fiber in case of W/B 30% respectively. In case of W/B 30% and 40%, flecxural strength shows largely in order of carbon fiber, metal lath, glass fiber. In strain-stress curve with the kinds of material for lateral confinement, while brittleness failure occurs in plain concrete just after maximum load, it is improved in some degree in confined concrete due to increase of the strain by increase of toughness. But, elastic modulus shows the similar tendency between confined concrete and plain concrete. Length change ratio by drying shrinkage shows little a bit in order of carbon fiber, glass fiber and metal lath due to confinement.

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Power Electronics Application in the Steel Industries -Induction Heating Equipment- (철강산업에서의 전력전자 기술응용-유도가열장비)

  • Shim, Eun-Yong;Yoo, Hyo-Yol;Kang, Jae-Bong
    • Proceedings of the KIPE Conference
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    • 2008.06a
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    • pp.12-14
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    • 2008
  • We have been trying to do our every efforts in various division in order to get more highly competition of products in steel industry, Especially, for the industry of cold mill, We are making high degree durability & elegant of steel plate from high quality plating & coating. Recently, Induction heating equipments are used to be choose in order to heat the steel plate in processing of drying and of curing after plating and coating are done. This paper will describe the theory of induction heating, consideration matters to decide power supply, structure of heating coil & manufacturing, operating methods etc, also it will present installation reference.

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Preparation and Properties of Hydroxyapatite/Methylcellulose for Bone Graft

  • Tak, Woo-Seong;Kim, Dong-Jun;Ryu, Su-Chak
    • Journal of the Korean Ceramic Society
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    • v.55 no.2
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    • pp.145-152
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    • 2018
  • Although many bone graft materials have been developed, powder graft materials are somewhat difficult to use in surgery. To solve this problem, a bone graft material in the form of a viscous paste was prepared. Hydroxyapatite was used as a bone graft material, and methyl cellulose was used to impart viscosity. Three cases of samples were prepared, and freeze-dried block type and sintered specimens were made from the paste. The recrystallization of the graft material in a simulated body fluid and the degree of graft adhesion with a tooth were observed by scanning electron microscopy (SEM). The test for cytotoxicity was carried out and the sample was grafted into the back of a mouse to confirm the presence or absence of side effects in the animal's body. Based on these investigations, composites of this type are expected to be applicable for bone grafts.

A Study on the Dinnerware Porcelain Bodies (식기용 자기소지에 관한 연구)

  • 장승현;정형진
    • Journal of the Korean Ceramic Society
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    • v.19 no.3
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    • pp.241-249
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    • 1982
  • Two dinnerware porcelain bodies involving partial replacement of feldspar and kaoline by about 35wt% domestic GYUNGJU-pottery stone were developed and their properties such as shrinkage, porosity, firing range, linear thermal expansion, pyroplastic deformation, degree of whiteness and mechanical strength were compared with those of a traditional clay-flint-feldspar body. The experimental results showed that one of the clay-flint-feldspar-pottery stone body with 1% ZnO addition had the firing range of 115$0^{\circ}C$~121$0^{\circ}C$, whereas the traditional body had the firing range of 12$25^{\circ}C$~129$0^{\circ}C$. The linear drying shrinkage and linear dry-to-fired shrinkage of all bodies were 2.5~4.5% and 15~18%, respectively. And the major crystalline phases of sintered bodies were $\alpha$-quartz and secondary mullite surrounded by glassy phases. The modulus of rutpture of sintered bodies was ranged from 860 to 870kg/$\textrm{cm}^2$, and the microhardness of sintered bodies was 680 kg/$\textrm{cm}^2$.

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Corrosion Evaluation of Epoxy-Coated Bars by Electrochemical Impedance Spectroscopy

  • Choi, Oan-Chul;Park, Young-Su;Ryu, Hyung-Yun
    • International Journal of Concrete Structures and Materials
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    • v.2 no.2
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    • pp.99-105
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    • 2008
  • Southern exposure test specimens were used to evaluate corrosion performance of epoxy-coated reinforcing bars in chloride contaminated concrete by electrochemical impedance spectroscopy method. The test specimens with conventional bars, epoxy-coated bars and corrosion inhibitors were subjected 48 weekly cycles of ponding with sodium chloride solution and drying. The polarization resistance obtained from the Nyquist plot was the key parameter to characterize the degree of reinforcement corrosion. The impedance spectra of specimens with epoxy-coated bars are mainly governed by the arc of the interfacial film and the resistance against the charge transfer through the coating is an order of magnitude higher than that of the reference steel bars. Test results show good performance of epoxy-coated bars, although the coatings had holes simulating partial damage, and the effectiveness of corrosion-inhibiting additives. The corrosion rate obtained from the impedance spectroscopy method is equivalent to those determined by the linear polarization method for estimating the rate of corrosion of reinforcing steel in concrete structures.

Review of the Studies on the Qualities in Peanut (땅콩의 품질평가 현황과 전망)

  • 박장환;박희운
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.47
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    • pp.163-174
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    • 2002
  • Peanut is one of the principal oil seeds in the world as a rich source of edible oil and protein. Peanut quality arises as a result of a complex interaction of genetic, physiological and biochemistry processes that produce the chemical composition of the peanut seed. The major factors influencing seed quality are degree of maturity and digging and drying, curing and storage as a series of harvesting. The end products, peanut butter, salted seed, confections, roasting stock and by-products are favored in world-wide because of their unique roasted peanut flavor, Literatures are reviewed mainly focusing on the physiological properties and nutritional quality of oil, protein and flavor in peanut. Chemical properties of protein and oil, and volatile flavor component in peanut seeds are studied. The objectives of this paper were to review and summarize the results obtained from the improving quality breeding program and evaluation of the chemical composition in peanut up to now.

A Study on the Fatty acid Composition and Malonaldehyde of Dried File Fish (쥐포의 지방산 조성과 Malonaldehyde 함량에 관한 연구)

  • 엽조애
    • Journal of the Korean Home Economics Association
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    • v.18 no.3
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    • pp.13-19
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    • 1980
  • To study the rancidity of dried file fish oil by Oxidation during the storage period, general properties of the oil and composition of its fatty acids were analysed qumtitatively with gas-chromatography. The results indicated that; 1) The dried file fish oil was involved in drying oil of heigh degree of unsaturation with IV 158., and consisted of higher-fatty acid with SV 190. 2) The composition of the fatty acids were composed of 18 fatty acids involving 6 unknown fatty acids, and polyunsaturated fatty acid with docosapentaenoic acid(20 weight%). 3) Changes of malonaldehyde content during the storage of dried file fish were about 5.0 mg/kg after 10day, 3.4 mg/kg after 40 days.

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A Study on the Pelletized Batch for $Na_2O-BaO-SiO_2$ System Glass ($Na_2O-BaO-SiO_2$ 계 유리조합물의 조립화에 관한 연구)

  • 박영원;강원호
    • Journal of the Korean Ceramic Society
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    • v.20 no.2
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    • pp.147-152
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    • 1983
  • For $Na_2O-BaO-SiO_2$ system glass the pelletizing conditions of the disk type equipment were investigated. The effects of the pelletized batch on melting were also examined. Through the experiment the optimum conditions for pelletizing the batch were found as follows. Revolving speed of the pan 30rpm pan angle 40-35 degree Water content 12-13% Drying temperature $200^{\circ}C$ Preheating temperature $650^{\circ}C$ The molten glass of the pelletized batch was refined better than that of the loose batch.

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The Skin Care Finishing of Polyester by Silk Sericin (실크 세리신을 이용한 폴리에스테르의 쾌적가공)

  • 한대만;배도규
    • Journal of Sericultural and Entomological Science
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    • v.41 no.3
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    • pp.185-195
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    • 1999
  • This study was carried out to improve the skin care property of the polyester fabric by finishing with sericin. It was known that skin care function, anti-oxidation, anti-tyrosinase activity and anti-elastase activity can be achieved from sericin finish. But, the moisture regain of the finished fabric was measured simply, because the major cause of the discomfort from polyester fabric has been anounced to be wetness. The effects of various treatment conditions on the properties of the finished fabric were measured, and obtained results were as follows: 1. The moisture regain at 40$^{\circ}C$ 90% RH were increased with the sericin uptake increasing. while it was not significant for the effects on the moisture regain depending on the treatment conditions like the degree of polymerization and treatment concentration of the binder. The moisture release of the fabric having sericin uptake 1%, 2% was faster than non treated fabric. The change of the moisture regain of the finished fabric from 40$^{\circ}C$ 90% RH to room temperature was 4∼5 times higher than that of knitted cotton fabric. 2. The frictional static charge was decreased with the degree of polymerization of the binder increasing. While the sericin uptake and treatment concentration of the binder were not significant. 3. The whiteness value of the fabric was slightly decreased by finishing with sericin and binder. In that cases, W values of the finished fabrics were above 90 while that depending on the degree of polymerization of the binder was not significant. 4. The major cause of the yellowness of the finished fabric was proved to be catalyst. The yellowness of the finished fabric with sulfur containing catalyst was lower than that with amine group containing catalyst. 5. The effects of the treatment concentrations of the cross-linking agent, catalyst and drying time on the wash durability were not significant.

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