• 제목/요약/키워드: Thermally stable

검색결과 340건 처리시간 0.028초

가스센서용 고순도 다공질 알루미나 담체의 제조 (Preparation of High-purity Porous Alumina Carrier for Gas Sensor)

  • 이창우;현성호;함영민
    • 한국화재소방학회논문지
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    • 제11권3호
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    • pp.15-23
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    • 1997
  • In this study, the alumina for gas sensor was prepared by anodic oxidation. It was stable thermally and chemically, and pore diameter and pore distribution was uniform. And the shape of pore was cylinderical. The aluminum plate was carried out by the thermal oxidation, chemical polishing and electropolishing pretreatment. The pore diameter, pore size distribution, pore density and thickness of alumina was observed with the change of reaction temperature, electrolyte concentration and current density. As a results, It was able to use for carrier because alumina which was prepared by anodic oxidationhas uniform pore size distribution.

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Electrical and Physical Evaluation of Processable Conductive PANI/PI Blends

  • Han, Moon-gyu;Im, Seung-soon
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 1998년도 가을 학술발표회논문집
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    • pp.219-222
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    • 1998
  • Polyaniline (PANI) has emerged as one of the most promising conducting polymers of the many types of conducting polymers in that it is soluble and therefore processable in the conducting form, and it is both environmentally and thermally stable together with high conductivity when it is doped by functionalized protonic acids like camphorsulfonic acid (CSA) and dodecylbenzenesulfonic acid (DBSA). (omitted)

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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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    • 제16권1호
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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.

Synthesis and Characterization of Poly[9,10-diphenylanthracene-4$^\prime$, 4$^\prime^\prime$-ylenevinylene-3,6-(N-2-ethylhexyl)carbazole]

  • 김윤미;박기민;권순기
    • Bulletin of the Korean Chemical Society
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    • 제22권9호
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    • pp.975-978
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    • 2001
  • A novel poly[9,10-diphenylanthracene-4',4"-ylenevinylene-3,6-(N-2-ethyl hexyl)carbazole] containing alternate diphenylanthracene and carbazole unit was synthesized by the Wittig reaction. The obtained polymer was soluble in common organic solvents and thermally stable up to 380 $^{\circ}C.$ The polymer gives rise to bright blue fluorescence both in solution and in thin solid films. The light emitted from the device (ITO/polymer/Al) was greenish-blue in color and clearly visible in daylight.

급랭응고한 Al-Fe-V-Si계 합금의 미세조직과 열안정성에 관한 연구 (Microstuctures and Themal Stability of Rapidly Solidified Al-Fe-V-Si-(Mn) Alloys)

  • 김선화;박원욱
    • Applied Microscopy
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    • 제21권2호
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    • pp.57-66
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    • 1991
  • The main purpose of this paper was to investigate the change of rapidly solidified microstructures and dispersoid behavior according to heat-treatment in the Al-Fe-V-Si-(Mn) alloys. It was found that (111) preferred orientation identified by X-ray diffraction and fine subgrain/large grain were observed in the rapidly solidified Al-Fe-V-Si-(Mn) alloys. Cell boundary of the zone A was composed of the microcrystalline, whereas that of the zone B was amorphous. Decomposition of the Al-Fe-V-Si-(Mn) alloys occurred at about $300^{\circ}C$. These alloys exhibited excellent thermal stability at the elevated temperature. Microstructure of the zone B was more stable than that of the zone A. The spherical dispersoid and 5-fold symmetry phase was also more thermally stable than the amorphous structure of cell boundary.

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Charge transport materials for the manufacture of OLEDs

  • Kathirgamanathan, Poopathy;Surendrakumar, S.;Ganeshamurugan, S.;Kumaraverl, M.;Paramaswara, G.;Partheepan, A.;Ravichandran, S.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.357-362
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    • 2006
  • OLEDs are becoming established as a commercially viable flat panel display technology of choice of the $21^{st}$ century because of its lightweight, fast response time, lower thickness than LCD's and potentially low cost (1-2). For the OLEDs to function effectively, highly thermally stable materials, which offer high efficiency and long operational lifetimes are required. To achieve long lifetime, highly stable charge (both holes and electrons) transporters are essential. OLED-T provides these materials as well as fluorescent and phosphorescent dopants. This paper reports a unique patented hole injector (E9363) and an electron transporter (E246) that increases the lifetime and efficiency and reduces operating voltage. Further, an electron injector, EEI-101, which evaporates at a very low temperature of $300^{\circ}C$ as opposed to the conventional LiF, which requires $580^{\circ}C$, is also presented.

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Synthesis and Characterization of the Thermally Stable Ho(hfa)3(tme)

  • Kang, Seong-Joo
    • Bulletin of the Korean Chemical Society
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    • 제25권8호
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    • pp.1207-1210
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    • 2004
  • Holmium $\beta$ -diketonate complexes, Ho(hfa)$_3$(tme), has been prepared and characterized by IR, TGA, MS, and single-crystal X-ray analyses. This complex is air- and moisture-stable and most importantly has good volatility and thermal stability. Holmium atom binds to nine oxygen atoms, contributed by six oxygen atoms of three hfa ligands and three oxygen atoms of the tme ligand. The coordination polyhedron of Ho can be described as a distorted tricapped trigonal prism. Crystal data for $Ho(hfa)_3(tme)$; orthorhombic $P2_12_12_1$, a = 15.415(4), b = 13.17(2), c = 17.291(3) $\AA$, V = 3496(1) ${\AA}^3$.

EFFECTS OF WINDS ON THE STABILITY OF A THIN DISK

  • LI, SHUANG-LIANG
    • 천문학논총
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    • 제30권2호
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    • pp.603-604
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    • 2015
  • Standard thin disk theory predicts that an inner disk region dominated by radiation pressure is thermally unstable. However, this kind of instability isn't detected in the observations of X-ray binaries. In this work, we revisit this issue by investigating the stability of a thin disk with magnetically driven winds. It is found that the disk winds can help to make a thin disk stable by taking away most of the energy released in the disk, resulting in a much cooler disk. The disk can always be stable even for a very weak initial field strength ${\beta}_{p,0}{\leq}400$ when ${\alpha}=0.05$ and $B{\phi}=10B_p$ are adopted.

열 보조 자기기록용 광 전달 레이저 모듈의 설계 및 평가 (Design and evaluation of laser module for light delivery in heat assisted magnetic recording)

  • 최용복;이문호;김영주
    • 정보저장시스템학회논문집
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    • 제7권1호
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    • pp.36-41
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    • 2011
  • The micro laser module was designed and prepared to deliver the light to the HAMR head. It consists of laser diode, photo diode and actuator to realize stable light delivery even though the head is fluctuated during the disk rotation. The optical evaluation was carried out with the actual distance between the light source and HAMR head with a range of reflectivity and it was found that the incident angle could be controlled within ${\pm}0.125^{\circ}$ to maintain same intensity into the HAMR head. It was also confirmed that the designed micro laser module is thermally stable without any severe effect on the magnetic head.