• Title/Summary/Keyword: Surface reforming

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A Study on the Commercial Streetscape Design Guideline of the Historic and Cultural Environmental Districts in Ancient Capital Gyeongju (고도(古都) 경주의 역사문화환경지구 내 상업가로경관 디자인가이드라인에 관한 연구)

  • Hyun, Taek-Soo
    • Journal of the Korean Institute of Rural Architecture
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    • v.16 no.1
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    • pp.87-94
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    • 2014
  • The objective of this study is to provide a townscape design guideline that harmonized with a historic landscape via condition investigation and landscape analysis of the cultural /commercial environment district where an improvement is a necessity. The followings are the conclusions: 1.To enhance the identity of Gyeongju, should pursue diversity in unity by making the image of architectural landscape a similar peculiarity. 2.The central commercial district where the tradition is valued and contemporary figures meet the tradition needs a landscape formation by CONTEXT. 3.Since a characteristic of the target area is a regional commercial center, to reduce its congestion, reforming the area to simple environment is required. 4.Induce buildings located on the streets with cultural properties to have Korean traditional tiled roof in order to fit in with their surroundings. 5.Make it a rule to partition a wall into tripartition, the wall surface exposed should be the same finishing materials. 6.Consider the visual aspect of pedestrians and a building's width, the recommendable height of the facade should be 3~3.6m. 7.For the design archetype of cornice, four traditional types based on Korean traditional eaves are suggested. 8.The design of signboards should break existing square-shapes, and seek a design to take advantage of icons that historicity and traditionalist of the city are expressed.

Synthesis and Characterization of waterborne polyurethane based on castor oil (Castor Oil 기반의 수분산 폴리우레탄의 합성 및 특성)

  • Bae, Ji-Hong;Kim, Eunyoung;Kang, Kyung Seok;Park, Duck-Jei
    • Journal of Adhesion and Interface
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    • v.18 no.4
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    • pp.179-182
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    • 2017
  • Waterborne polyurethanes(WPU) based on castor oil were successfully prepared using polycaprolactone diol(PCL), castor oil(CO) and 4,4'-methylene dicyclohexyl diisocyanate($H_{12}MDI$) as soft segment part, dimethylolbutanoic acid (DMBA) as emulsifier, and trimethylamine(TEA) as neutralizer based on different molecular weight of prepolymer. The various properties such as mechanical strength and surface reforming were evaluated using UTM, contact angle, FE-SEM based on the different molecular weight of polyol. Waterborne polyurethanes based on castor oil could be considered as a promising candidate to be applied the various adhesion fields.

Dielectric Loss Tangent Measurement Using the $Al_{2}O_{3}$ Crystal Capacitor ($Al_{2}O_{3}$ Crystal Capacitor를 이용한 유전손실 측정)

  • Kim, Kwang-Soo;Her, In-Sung;Lee, Chong-Chan;Park, Dea-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.08a
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    • pp.109-122
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    • 2002
  • The standard capacitor must have not only precise value of the capacitance but also the basic properties of low dielectric loss tangent. In the reforming process of capacitors, the dielectric loss tangent must be also reformed. In this paper, the development of standard capacitors of 10 and 100pF for the dielectric loss tangent standard using $Al_{2}O_{3}$ Crystal and the measurement of dielectric loss tangent are discussed. The dielectric loss tangent depends upon the surface between electrode and dielectric in capacitor. With using the Electric Field Simulator, precise design values of electrode are simulated. For the purpose of measuring capacitance effect just in the dielectric, 3-Terminal and 4-Terminal Pair configuration are applied respectively at the electrode and the connector for the measuring equipment. As stated above method, the standard capacitors of 10 and l00pF for the establishment of the dielectric loss tangent standard using the $Al_{2}O_{3}$ Crystal are made with low dielectric loss tangent less than 10-4.

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A Study on the Removal of Heavy Metals Using Functional Group on the Surface of Discarded Automotive Tires (폐타이어 표면에 형성되는 Functional Group을 이용한 중금속 제거에 관한 연구)

  • Lee, Yong-Doo;Ko, Deuk-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.3
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    • pp.357-364
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    • 2007
  • This research is to set a direction on the recycle of Discarded Automotive tires reforming them into heavy metal adsorbents by developing a particular functional group inducing formation of Chelate complexes with heavy metal ion in the water, on the surface of the used tire conventionally turned into powdered form. For this purpose, through FT-IR, XRD, XRF, SEM, elution test we confirmed and analyzed the property of newly reformed scrapped tires, and functional group. Also, by Kinetics Study we produced an invariable value applying to absorption models. Conclusively the absorption preference of heavy metal is determined to be $Pb^{2+}>Cu^{2+}>Cd^{2+}$, and it reached absorption balance within first 30 minutes, also the absorption reaction time increased from 0.27 to $1.78\sim3.15(g/mg{\cdot}min)$, and showed more than 80% of removal efficiency. This result proved that the efficiency increased by 10 times compared with the conventional powdered Discarded Automotive tires, and the Discarded Automotive tire which implemented the Functional group can exhibit a great efficiency as heavy metal adsorbent.

Structure and Reactivity of Bimetallic Catalyst (이원금속 촉매의 구조와 반응성)

  • Yie, Jae-Eue
    • Applied Chemistry for Engineering
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    • v.3 no.1
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    • pp.24-34
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    • 1992
  • Recent studies dealing with the fundamental understanding and applications of bimetallic catalysts are discussed. Bimetallic catalysts have had a major industrial impact, specifically for the reforming of petroleum naphtha, for the hydrogen reduction of carbon monoxide, and for the three way catalytic converter system. The action of the bimetallic catalysts in these reactions may be interpreted in terms of ensembles, electronic influences and surface structure. Various combinations of metal pairs have been considered in order to evaluate the role played by the added metals. For catalyst selectivity control, the possibility of surface enrichment of one element has been recognised. More generally, the influence of preparative variables on the formation of supported catalysts has been clarified, In particular by temperature programmed reduction (TPR). Information on the structure of bimetallic catalysts has been obtained with chemical probes, such as chemisorption and reaction rate measurement and physical probes, such as extended X-ray absorption fine structure (EXAFS), scanning transmission electron microscopy (STEM) and Xe-NMR.

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Studies on the Printability of Hanji by Sizing and Calendering

  • Kang Jin-Ha;Seo Seung-Man;Park Seong-Cheol
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.37 no.5 s.113
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    • pp.70-77
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    • 2005
  • The development of printable Hanji is regarded as an important work to create a new demand of Hanji in information-oriented era. Hanji has rougher surface, huger absorption of ink and lower optical properties and printabilities than common printing papers. Improving those shortcomings of Hanji is required to be printable Hanji. Sizing and calendering have known as a way to make properties of paper good. Accordingly, this research was performed to find out useful sizing agents for reforming its drawbacks. Four sizing agents (CMC, com starch, PVA, AKD) were used in this research. The optical properties and the printabilities of sized Hanji were tested. The obtained results were as follows. Based on concentration, each sizing agent was prepared. These were CMC(0.5, 1, $1.5\%$), corn starch(1, 2, $3\%$), PVA(1, 5, $10\%$), AKD(0.5, 0.1, $0.15\%$) respectively. After sizing, we performed calendering treatment with pressure of 0.5, $1\;kgf/cm^2$. All the sizing agents and calendering treatment improved the properties of Hanji to some extent. Particularly, com starch was good for gloss. In case of printability, $1\%$ AKD with $1\;kgf/cm^2$ was recommendable for typography ink density, $3\%$ com starch with $0.5\;kgf/cm^2$, inkjet ink density, $2\%$ com starch with $0.5\;kgf/cm^2$, inkjet ink girth. PVA and AKD without calendering were counter-effective agents for inkjet ink density. Printable Hanji is required to have not only better surface strength enough to appear non-picking, higher ink density and lower show-through than base paper but also the lowest ink girth in comparison with base paper. When referring to them, efficient sizing agents were regarded as $0.1\%$ AKD with $1\;kgf/cm^2$, calender pressure, for typography printing and $2\%$ com starch with $0.5\;kgf/cm^2$, calender pressure, for inkjet printing.

Poisoning of the Ni/MgO Catalyst by Alkali Carbonates in a DIR-MCFC (용융탄산염 연료전지에서 알칼리 탄산염에 의한 Ni/MgO 촉매의 피독)

  • Moon, Hyeung-Dae;Kim, Joon-Hee;Ha, Heung Yong;Lim, Tae-Hoon;Hong, Sung-Ahn;Lee, Ho-In
    • Applied Chemistry for Engineering
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    • v.10 no.5
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    • pp.754-760
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    • 1999
  • The properties of the catalyst for a direct internal reforming type molten carbonate fuel cell were examined by ICP, BET, CHN, EDS, and $H_2$ chemisorption. Potassium and lithium, the components of carbonate electrolyte, were transported to the catalyst during the operation of fuel cell, and the amounts of the deposited alkali elements were reduced in the order of inlet, outlet, and the middle. From the direct correlation between the amount of alkali and the physical properties such as BET surface area and Ni dispersion, and from the observation of the lump of the alkali species on the poisoned catalyst, it was confirmed that the physical blocking of the catalyst by alkali deposition was the main reason for the deactivation. Although the amount of alkali species was greater at the inlet than at the oulet, the catalyst sampled from the outlet had lower activity. This was caused by the chemical interaction between the alkali species and the catalyst at the outlet where temperature was highest in the cell body, which was detected by FT-IR analyses.

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Methane Conversion to Hydrogen Using Ni/Al2O3 Catalyst (Ni/Al2O3 촉매를 이용한 메탄의 수소 전환)

  • Kim, Jun-Keun;Park, Joo-Won;Bae, Jong-Soo;Kim, Jae-Ho;Lee, Jae-Goo;Kim, Younghun;Han, Choon
    • Applied Chemistry for Engineering
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    • v.19 no.5
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    • pp.466-470
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    • 2008
  • The objective of this study is to convert methane into hydrogen using a nanoporous catalyst in the $CO_2$ containing syngas generated from the gasified waste. For the purpose, $Ni/Al_2O_3$ catalyst was prepared with the one-pot method. According to analyses of the catalyst, three dimensionally linked sponge shaped particles were created and the prepared nanoporous catalysts had larger surface area and smaller particle size and more uniform pores compared to the sphere shaped commercial catalyst. The catalyst for reforming reaction gave the highest $CH_4$ conversion of 91%, and $CO_2$ conversion of 92% when impregnated with 16 wt% of Ni at the reaction temperature of $750^{\circ}C$. At that time, the prepared catalyst remarkably improved the $CH_4$ and $CO_2$ conversion up to 20% compared to the commercial one.

Non-gaseous Plasma Immersion Ion Implantation and Its Applications

  • Han, Seung-Hee;Kim, En-Kyeom;Park, Won-Woong;Moon, Sun-Woo;Kim, Kyung-Hun;Kim, Sung-Min
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.151-151
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    • 2012
  • A new plasma process, i.e., the combination of PIII&D and HIPIMS, was developed to implant non-gaseous ions into materials surface. HIPIMS is a special mode of operation of pulsed-DC magnetron sputtering, in which high pulsed DC power exceeding ~1 kW/$cm^2$ of its peak power density is applied to the magnetron sputtering target while the average power density remains manageable to the cooling capacity of the equipment by using a very small duty ratio of operation. Due to the high peak power density applied to the sputtering target, a large fraction of sputtered atoms is ionized. If the negative high voltage pulse applied to the sample stage in PIII&D system is synchronized with the pulsed plasma of sputtered target material by HIPIMS operation, the implantation of non-gaseous ions can be successfully accomplished. The new process has great advantage that thin film deposition and non-gaseous ion implantation along with in-situ film modification can be achieved in a single plasma chamber. Even broader application areas of PIII&D technology are believed to be envisaged by this newly developed process. In one application of non-gaseous plasma immersion ion implantation, Ge ions were implanted into SiO2 thin film at 60 keV to form Ge quantum dots embedded in SiO2 dielectric material. The crystalline Ge quantum dots were shown to be 5~10 nm in size and well dispersed in SiO2 matrix. In another application, Ag ions were implanted into SS-304 substrate to endow the anti-microbial property of the surface. Yet another bio-application was Mg ion implantation into Ti to improve its osteointegration property for bone implants. Catalyst is another promising application field of nongaseous plasma immersion ion implantation because ion implantation results in atomically dispersed catalytic agents with high surface to volume ratio. Pt ions were implanted into the surface of Al2O3 catalytic supporter and its H2 generation property was measured for DME reforming catalyst. In this talk, a newly developed, non-gaseous plasma immersion ion implantation technique and its applications would be shown and discussed.

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A study on the improvement of hydrophilic properties of activated carbon surface by nitric acid treatment (질산 처리에 따른 활성탄 표면의 친수성 특성 향상에 관한 연구)

  • Kang, Hye Ju;Yang, So Yeong;Kim, Tae Min;Kim, Yong Ryeol
    • Journal of the Korean Applied Science and Technology
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    • v.38 no.5
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    • pp.1241-1248
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    • 2021
  • In order to figure out various environmental problems, various governments and companies are investigating more environmentally policies and technologies. In other words, activated carbon is widely used for the adsorption of different harmful gases and waste liquid treatment. However since the required surface properties are different in various industry, depending on the adsorption properties, the development of activated carbon demand in different ways. In this work, we have investigated and developed the activated carbon surface to improve the hydrophilic properties by nitric acid treatment through reforming of activated carbon.