• Title/Summary/Keyword: 오린 3.3

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Behaviors of Atomic Fluorine and Fluorocarbon Radicals in $CF_4+H_2$Electron Cyclotron Resonance Plasma Employing Actinometry and Appearance Mass Spectrometry (전자 회전 공명 플라즈마 발생 장치에서의 $CF_4+H_2$가스 방전시 Appearance Mass Spectrometry와 Actinometry를 통한 플루오로카본 래디칼과 플루오린 원자의 거동에 관한 연구)

  • 도현호;김정훈;이석현;황기웅
    • Journal of the Korean Vacuum Society
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    • v.4 no.4
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    • pp.417-424
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    • 1995
  • 전자 회전 공명 플라즈마 발생 장치에서 CF4를 방전시켰을 때 각종 플루오로카본 래디칼의 절대적, 상대적 밀도 변화를 수소 철가율, 동작 압력 그리고 축방향에 따라 appearace mass spectrometry(AMS)를 통해 조사하였으며, 플루오린 원자의 상대적 밀도 변화가 actinometry법에 의해 조사되었다. 수소첨가에 따른 CF2 래디칼의 거동을 actinometry와 AMS로 살펴보았을 때 서로 일치하는 경향을 얻었으며 마이크로웨이브전력 500W, 압력 7.5mTorr에서 CF3와 CF2 래디칼의 밀도가 CF에 비해 높았으며 각각 2X1013/㎤, 1X1013/㎤의 값을 가졌다. 수소를 첨가함에 따라 플루오린 원자와 CF3의 밀도는 감소하는 반면 CF2와 CF의 밀도는 현저히 증가하여 수소가 40% 첨가된 경우 CF2의 밀도가 CF3보다 커짐을 확인하였다. 또한, CF2가 증가하면서 C2F4의 존재가 확인되었으며, 수소가 30% 첨가된 경우 축방향을 따라 C2F4래디캄만이 증가하였고 플루오린 원자는 감소하는 반면 다른 CFx(x=1~3)래디칼은 거의 변화가 없었다. 이러한 실험 결과를 토대로 CF4+H2 플라즈마를 이용한 산화막 식각 특성이 설명되었다.

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Synthesis and Antitumor Activity of 3'-hydroxydaunorubicin and 3'-hydroxydoxorubicin Derivatives Substituted with 4'-fluorine or 4'-azide in Sugar Moiety (당부분에서 4'-플루오린 또는 4'-아자이드로 치환된 3'-히드록시다우노루비신과 3'-히드록시독소루비신 유도체의 합성과 항암활성)

  • Ok, Kwang-Dae;Park, Jeong-Bae;Kim, Moon-Sung;Jung, Dong-Yoon;Yang, Junn-Ick
    • YAKHAK HOEJI
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    • v.40 no.2
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    • pp.117-125
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    • 1996
  • 3'-Deamino-3-hydroxy-4'-fluoro- or 3'-deamino-3'-hydroxy-4'-azido-daunorubicin(6,8) and -doxorubicin(7,9) have been synthesized, respectively. Compounds 7,8 and 9 were mo re cytotoxic than daunorubicin(1) and doxorubicin(2) against L1210 murine leukemic cell in vitro. When administered intraperitoneally for 9 days starting 1 day after tumor inoculation, compounds 7(T/C 605%) and 9(T/C 488%) showed significant antitumor activity for ip-inoculuated L1210 murine leukemia at wide range of doses.

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Preparations of ASC Refractory Materials from Kaolin using Thermit Reaction (카오린으로부터 테르밋 반응을 통한 $Al_2O_3-SiC-C(ASC)$계 내화재료 합성)

  • 이온영;이용구;전병세
    • Journal of the Korean Ceramic Society
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    • v.32 no.4
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    • pp.429-435
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    • 1995
  • Al2O3-SiC-C(ASC) refractory materials were prepared from kaolin using thermit reaction. The mixed powder (A-K) for the thermit reaction was composed of Hadong kaolin, C(graphite) and Al. A-S(SiO2+C+Al) composition was also employed to compare with A-K in respect to reactability. As a result of XRD patterns of A-K sample after thermit reaction, and firing at 140$0^{\circ}C$ for 3hrs in Ar atmosphere, it was possible to use as a ASC refractory materials.

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A Study on the Extraction of Alumina from Kaolin (카오린으로부터 $Al_2O_3$의 용출에 관한 연구)

  • 백용혁;이종근
    • Journal of the Korean Ceramic Society
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    • v.19 no.2
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    • pp.157-161
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    • 1982
  • The possibility of extraction of alumina from domestic Ha-dong kaolin was studied by sulfuric acid treatment. Raw kaolin was calcined at various temperature (500-110$0^{\circ}C$) and calcined kaolin were treated with sulfuric acid. The tendency of extraction yield of alpha alumina have been investigated by relating reaction time, temperature, and acid concentration. After reaction, precipitates were analyzed by DTA, TGA, and identified alpha alumina by X-ray diffractometer with calcined sample at 120$0^{\circ}C$. The results were as follows; 1. The optimum calcination temperature was 800-86$0^{\circ}C$. 2. The most suitable extracting conditions of alpha alumina were 40 wt%-$H_2SO_4$, 2-3 hours acid-treating time and 8$0^{\circ}C$ acid-treating temperature. 3. Precipitates were composed of $(NH_4)_2SO_4$, $Al_2SO_4(OH)_4$ 5-7 $H_2O$ and $Al(OH)_3$.

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Sorption of Radioactive Cobalt and Ruthenium on Soil Minerals (방사성 코발트 및 루테늄의 토양 흡착)

  • Lee, Byung-Hun;Hands, J.D.
    • Journal of Radiation Protection and Research
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    • v.15 no.2
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    • pp.7-16
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    • 1990
  • The sorption of radioactive cobalt and ruthenium on alumina, silica gel, zeolite 3A, kaolin and Na-bentonite has been studied as a function of pH. nuclide concentration and ionic strength. Retardation factor for cobalt and ruthenium on soil minerals was determined through porosity measurement. Hydrolysed species, cobalt and ruthenium interact with solid surfaces by physical adsorption processes. Freundlich sorption isotherms for cobalt and ruthenium are effectively linear. The sorption decreases with increasing ionic strength for cobalt and ruthenium. The effect of increasing porosity on the retardation factor countered the effect of a significant increase in the distribution coefficient.

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A Study on the Copper Metallizing Method of $Al_2$O$_3$ Ceramic Surface (알루미나(Al$_2$O$_3$) 세라믹 표면의 강메탈라이징법에 관한 연구)

  • ;;Choi, Y. G.;Kim, Y. S.
    • Journal of Welding and Joining
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    • v.13 no.3
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    • pp.55-64
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    • 1995
  • Metallizing method on ceramic surface is one of the compositing technology of ceramics and metal. The purpose of this study is to make HIC (Hybrid Intergrated Circuit) with copper metallizing method of which copper layer is formed on ceramic substrate by firing in atmosphere in lieu of conventional hybrid microcircuit systems based on noble metal. Metallizing pastes were made from various copper compounds such as Cu$_{2}$O, CuO, Cu, CuS and kaolin. And the screen printing method was used. The characteristics of metallized copper layers were analyzed through the measurement of sheet resistance, SEM, and EDZX. The results obtainted are summarized as follows; 1. The copper metallizing layers on ceramic surface can be formed by firing in air. 2. The metallized layer using Cu$_{2}$O paste showed the smallest sheet resistance among a group of copper chemical compounds. And optimum metallizing conditions are 15 minutes of firing time, 1000.deg.C of firig temperature, and 3 minutes of deoxidation time. 3. The results of EDAX analysis showed mutual diffusion of Cu and Al. 4. The kaolin plays a important role of deepening the penetration of Cu to $Al_{2}$O$_{3}$ ceramics. But if the kaolin content is too much, sheet resistance increases and copper metallizing layer becomes brittle.

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Effect of Meteorin on the Regulation of TSP-1 via $PKC\delta$ Signalings in Astrocytes (성상세포에서 메테오린에 의한 TSP-1 발현조절에 $PKC\delta$ 신호경로의 연관성)

  • Park, Soo-Youn;Lee, Hye-Shin;Ko, Keum-Jae;Park, Jeong-Ae
    • YAKHAK HOEJI
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    • v.53 no.3
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    • pp.151-155
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    • 2009
  • Meteorin in astrocytes has antiangiogenic activities via thrombospondin-1 (TSP-1), however, the regulatory mechanism has been unclear. Here we report that Meteorin upregulates TSP transcriptionally through luciferase reporter assays in astrocytes. Moreover, Meteorin activates $PKC\delta$ and ERK1/2 in astrocytes. Inhibition of $PKC\delta$ and ERK1/2 activities attenuated expression of TSP-1 by Meteorin in astrocytes. We, therefore, demonstrate that Meteorin activates $PKC\delta$ signaling and, in turn, increases TSP-1 expression in astrocytes to inhibit angiogenesis in the brain.

Synthesis of trans, trans-4-(2-Fluoro-3-isothiocyanato-4-propylphenyl)-4-alkylbicyclohexyl for Liquid Crystal Display (액정 디스플레이를 위한 트랜스, 트랜스-4-(2-플르로로-3-아이소싸이오싸이아네이토-4-프로필페닐)-4'-알킬바이싸이클로헥실의 합성)

  • Lee, Seon-Hui;Kim, Seong-Hun
    • Journal of the Korean Chemical Society
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    • v.48 no.5
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    • pp.499-503
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    • 2004
  • We designed and synthesized compounds which have negative dielectric anisotropy (N type) for VA-LCD mode. Due to the large dipole moments toward the minor axis of molecule and anisotropy of polarizability, they can be used as N type LC. F atom and NCS group and propyl group were introduced as substituents on bicyclohexylbenzene core unit and alkyl chains (propyl~heptyl) were introduced on terminal part. All of the synthesized compounds showed negative dielectric anisotropy as expected.

A study on the brazed bonding of alumina ceramic to aluminum in the air atmosphere (알루미나($Al_2O_3$)세라믹과 알루미늄(A1050)과의 대기중 브레이징 접합에 관한 연구)

  • 최영국;박성현;김윤해;김영식
    • Journal of Advanced Marine Engineering and Technology
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    • v.19 no.3
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    • pp.50-61
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    • 1995
  • In recent years, many ceramic researchers have discoved various methods of joining ceramic to metal. However, most of these joining methods are perfomed under vacuum and pressured circumstances. So, when we join ceramic to metal,the proceedings are very complicated and require a very high cost. The purpose of this study is to develop a new joining method of an alumina ceramic to an aluminum metal in air atmosphere. The joining condition, such as copper metallizing, nickel plating, brazing, etc. was investigated through the shear strength test of the trial joint. The results obtained from the above experimenta are summarized as follows : 1) In the case of the $Al_2O_3$/$Al_2O_3$joint, the shear strength of the joint was affected by the various foctor such as kaolin content, copper metallizing thickness, firing temperature, firing time. 2) The better shear strength of the $Al_2O_3$/Al joint was obtained when Ni plating was conducted under higher current density than existing plating condition. 3) The shear strength of the $Al_2O_3$/Al joint increases with the Ni plating thickness is confined to the range of this paper. 4) The shear strength of the thermal-shocked specimen($Al_2O_3$/Al joint) was far more deteriorated than that of the as-bonded specimen.

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Adsorption Equilibrium of Rhodamine 6G onto the Conchiolin Layer from Aqueous Solution (수용액중의 Rhodamine 6G 염료의 콘키오린 층에 대한 흡착평형)

  • Shin Choon-Hwan;Song Dong-lk
    • Journal of Environmental Science International
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    • v.14 no.12
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    • pp.1195-1201
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    • 2005
  • In order to develop a dye coloring technology on Conchiolin layer in cultured pearls, appropriate dyes were selected, their solubilities in various solvents were studied, and adsorption and desorption experiments were performed. Solubilities of several basic dyes known to suitable for the pearl coloring, i.e., Rhodamine 6G(R6), Rhodamine B(RB) and Methylene Blue(MB), in several solvents (distilled water, methanol, ethanol, and acetone) were investigated. Among these dyes, R6 was chosen as a dye for single component adsorption and desorption experiment due to the relatively good solubility in various solvents tested. Solubilities of dyes were judged to be enough to color the pearls since dye concentrations in pearl coloring are, in general, not so high. The internal surface area of the pearl layer is believed to be directly related to the dye adsorption, the single-point internal surface area of the pearl layer measured at the nitrogen relative pressure of 0.3 was found to be $0.913m^2/g$, and the BET internal surface area, $1.01m^2/g$ The most probable diameters of micropores and macropores were found to be $40{\AA}$and $5000{\AA}$ respectively, from the pore size distribution data. Adsorption isotherm was well fitted to the Langmuir isotherm model, resulting in q=$\frac{1.62C}{1+1.09C^{.}}$