• Title/Summary/Keyword: compounding

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Natural Rubber-Clay Nanocomposites by Latex Method : Morphology and Mechanical Properties (라텍스법에 의한 천연고무-클레이 나노 복합재료: 모폴로지와 기계적 물성)

  • Kim, W.H.;Kang, J.H.;Kang, B.S.;Cho, U.R.
    • Elastomers and Composites
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    • v.41 no.1
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    • pp.27-39
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    • 2006
  • In this study, modified DA-MMT filled NR/DA-MMT nanocomposites were manufactured by a latex method and a compounding method. Cure characteristics and mechanical properties of the Cloisite 15A, carbon black, Na-MMT filled NR compounds and the DA-MMT filled NR compound by a latex method were also evaluated. The filler content of all compounds was 10phr except the carbon black filled compound. Degree of intercalation and dispersion was characterized by X-ray diffraction (XRD) and transmission electron microscope (TEM). According to the XRD diffraction pattern and TEM analysis, extensive intercalation and homogeneous dispersion of the clay were obtained after the two-roll milling. Although the layer distance was increased, some parts of DA-MMT showed the layer distance of Na-MMT after vulcanization. DA-MMT filled NR compounds showed the highest ODR torques, tensile strength, modulus, and tear energy. The NR/DA-MMT nanocomposite (by a latex method) compared with a NR/DA-MMT nanocomposite (by a compounding method) was found that the improvement of the mechanical properties was mainly due to the degree of dispersion of the clay.

Design and Combonatorial Synthesis of Selenoflavonoids and Indole Compounds for Neuroprotective Drug

  • Jeong, Jin-Hyun
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.69-71
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    • 2003
  • As recent as 10 years ago, a method of developing new medicine was developed by a new compounding method moving away from an existing one. Combinatorial chemistry made it easier to combine various kinds of compounds in a very short time and with little effort from existing methods. Through combinatorial chemistry, a number of compounds were synthesized using HTS(High Throughput Screening), with many reports reaching a clinical stage in search of new candidate material. (omitted)

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Preparation and Characterization of Nylon 6/MMT Nanocomposite Fiber (나일론6/MMT 나노복합체 섬유의 제조 및 특성)

  • ;;Angelica S. Lopez.
    • Proceedings of the Korean Fiber Society Conference
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    • 2003.10b
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    • pp.219-220
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    • 2003
  • 나일론 6의 열변형온도와 탄성률을 증가시키는 동시에 높은 기체 차단성을 얻기 위하여 Na-montmorillonite (Na-MMT) 또는 유기화제로 개질된 MMT (organo-MMT)를 나일론 6과 melt-compounding함으로써 나일론 6 분자쇄가 MMT 층 내로 intercalation하거나 MMT의 각 층을 완전히 exfoliation시켜 나일론 6/MMT 나노복합체를 제조하는 방법과 Na-MMT 또는 organo-MMT의 존재하에서 $\varepsilon$-caprolactam (CL)을 in situ 중합함으로써 대부분의 MMT가 각각의 층으로 exfoliation 되도록하여 나일론 6/MMT 나노복합체를 제조하는 방법이 널리 쓰이고 있다 [1-2]. (중략)

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Electrochemical characteristics of EDLC with conducting polymer as a additives (전도성고분자를 첨가제로 이용한 supercapacitor의 전기 화학적 특성)

  • 오호성;김경민;정세일;오응주;강안수
    • Proceedings of the Safety Management and Science Conference
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    • 2001.11a
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    • pp.157-160
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    • 2001
  • The electrodes were fabricated by compounding the commercial activated carbons and additives of conducting polymer with PVdF mono binder and PVdF-PVP mixed binders. The best performance of the electrodes fabricated with activated carbon(BP-20) and PVdF-PVP mixed binders showed in 88wt. % BP-20. 7wt. % conducting polymer and 5wt.% PVdF-PVP mixed binder. The electrode exhibited excellent electrochemical characteristics having 8.16 W.h/kg of energy density, 34.77 F/g of specific capacitance, $0.67\Omega$of ESR.

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DCF Formulae for the Case of Simultaneous Random Variations of the Rates of Inflation and Return (할인율과 인플레율이 동시에 확율분포를 취할 경우의 DCF공식)

  • 최진영;정동길
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.6 no.9
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    • pp.27-33
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    • 1983
  • This Paper represents time-dependent stochastic variations of common discounted cash flow formulae with explicit consideration given to inflation. The cash flow, the ratio of discounting or compounding, and the rate of inflation are allowed to vary with time in a random fashion in equations for the compound amount of a single payment, present worth of a single payment, amount of an annuity, periodic deposits to accumulate a future amounts, present worth of an annuity and capital recovery And all formulae are derived for the case of discrete random variations.

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A Potential Flame-retardant by Intumescence. Melaminium 2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-4-methoxy-sulfates

  • 김진규;조양하;정옥상;손윤수
    • Bulletin of the Korean Chemical Society
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    • v.16 no.1
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    • pp.62-65
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    • 1995
  • New compounds of melaminium 2,6,7-trioxa-1-phosphabicyclo[2.2.2]octane-4-methoxy-sulfate have been synthesized and characterized by means of chemical analysis, 1H, 13C, and 31P NMR, and IR spectroscopies. When the compounds are subjected to an open flame, they foam without melting to produce a light char with about 50 times volume of the initial compounds. The evaluation of these flame-retardants proves to be efficient for polypropylene. Thermogravimetric analysis discloses that the compounds are also thermally stable for compounding into polypropylene without decomposition.

Construction of Indole Library for Serotonin Related Drugs and Macrocyclization Using Selenium Chemistry in Solid-Phase Reaction.

  • Mun, Han-Seo;Jeong, Jin-Hyun
    • Proceedings of the PSK Conference
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    • 2003.04a
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    • pp.246.1-246.1
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    • 2003
  • Hetero chain compounds have high possibilities of being good medicinal candidate because of their well-known medicinal activity and relatively low subtitled carbon. By constructing the method of making this compound library, this research has the purpose to create a new medicinal candidate materials based on an easy medicinal search. The first step is to construct an Indole library in a compounding process with the design of a linker connecting a solid-state resin and a substrate. (omitted)

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Improvement of Optical and Thermo-mechanical Properties of Polycarbonate-based Diffusers for LED Backlight Unit by Incorporation of Porous Silica Particles (실리카 다공체에 의한 발광다이오드 백라이트 유닛용 폴리카보네이트계 확산판의 광학 및 열-기계적 물성의 향상 연구)

  • Kim, Hyo Jin;Kim, Dong Won;Kim, Seong Woo
    • Polymer(Korea)
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    • v.36 no.6
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    • pp.761-767
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    • 2012
  • The polycarbonate (PC)-based optical diffusers for direct-lit LED backlight unit were prepared by using extrusion compounding followed by compression molding process. The application of inorganic porous silica particles as a diffusing agent in addition to conventional poly(methyl methacrylate) (PMMA) beads was attempted, and the optical, thermal, and mechanical properties of the prepared diffusers were investigated. The morphological observations revealed that the diffusing agents could be uniformly dispersed in the PC matrix without agglomeration by high shear stress generated during extrusion process. The incorporation of the porous silica particles mixed with PMMA beads remarkably enhanced the luminance uniformity with respect to both location and view angle for the diffuser, while minimizing the reduction in the absolute luminance, as compared with the diffuser containing only PMMA beads. In addition, thermal and mechanical properties of the diffusers were shown to be improved upon addition of the porous silica particles.

An Analysis of Pre-Service Teachers' Understanding of the real number e (예비교사들의 실수 e에 대한 이해)

  • Choi, Eunah;Lee, Hong-Youl
    • Journal of the Korean School Mathematics Society
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    • v.20 no.4
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    • pp.495-519
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    • 2017
  • The purpose of this study is to analyze the concept of the real number e and to investigate the understanding of pre-service teachers about the real number e. 28 pre-service teachers were asked to take a test based on the various ideas of the real number e and 8 pre-service teachers were interviewed. The results of this study are as follows. First, a large number of pre-service teachers couldn't recognize relation between the formal definition and the representations of the real number e. Secondly, pre-service teachers judged appropriately for the irrationality and the construction impossibility of the real number e, but they couldn't provide reasonable evidence. Lastly, pre-service teachers understood the continuous compounding context and exponential function context of the real number e, but they had a difficulty in understanding the geometric context and natural logarithm context of the real number e.

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A Study on Flower Patterned Fabrics of Exhumed Clothing in Chosun Dynasty (조선시대 출토직물에 나타난 화문직의 특성에 관한 연구)

  • Park, Mun-Young;Kim, Ho-Jung
    • Fashion & Textile Research Journal
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    • v.10 no.1
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    • pp.22-29
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    • 2008
  • In this study, it is investigated the types and the compounding method of flower patterns and the uses of flower patterned fabrics in Chosun Dynasty. Research was done through the references of exhumed clothing during 16-17th century. Our ancestors had used the various flower patterns based on Buddhism, Taoism and Confucianism onto the fabrics. The flower patterns on the fabrics were expressed with the other patterns such as treasure patterns, letter patterns or bird patterns. And the flower patterns symbolized the various good meanings such as longevity, integrity and prosperity etc. In the order of the percentage, the types of the flower patterns were shown Lotus(27.31%), Arabesque(26.85%), Japanese apricot(14.81%), Peony(8.79%), Flowering plants(6.94%), Chrysanthemum(6.01%), Pomegranate(2.31%) patterns and so on. Especially the Lotus pattern was shown up most frequently. That of shape was designed as blooming(開花), full bloom(滿開) and the side of flower(側面). By the compounding method, the compound types mixed with the other patterns were used much more than the individual types composed by its own pattern. The flower patterns were used a lot in Jeogori(Jacket) regardless of the ganders and in men's Po(coat) including Cheollik(天翼), Dappo(胡), Jeonbok(戰服), Dahnryoung(團領), etc. Also contrary to these days, the flower patterned fabrics had come out in the shrouds. Judging from these facts, our ancestors wished that the meaning of the immortal life was included in the flower pattern.