• Title/Summary/Keyword: Tris

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Synthesis of Phosphates and Phosphoric Amides (Ⅱ) (Phosphates 및 Phosphoric Amides의 합성 (제2보))

  • Kil-Yeong Choi;Sam-Kwon Choi
    • Journal of the Korean Chemical Society
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    • v.24 no.6
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    • pp.463-468
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    • 1980
  • Tris(hydroxyethyl) phosphate, ethylphosphoramidic dichloride, N,N-diethylphosphoramidic dichloride, bis(hydroxyethyl) N-ethylphosphoramidate and bis(hydroxyethyl) N,N-diethylphosphoramidate were synthesized and characterized. Phosphate and phosphoramidates were polymerized with the elimination of ethylene glycol when heated under reduced pressure and they gave no molecular ion peaks in their mass spectra. And also ethylphosphoramidic dichloride gave polymeric products at 180$^{\circ}C$ with the evolution of HCl. IR spectra showed characteristic P=O streching bands in the range of 1,300 to$ 1,200 cm^{-1}.$

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Ir(ppy)3의 도핑 위치에 따른 유기 발광 다이오드의 특성 연구

  • Kim, Sun-Gon;Choe, Byeong-Deok
    • Proceedings of the Korean Vacuum Society Conference
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    • 2015.08a
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    • pp.151.2-151.2
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    • 2015
  • 본 연구에서는 indium-tin-oxide(ITO)/1,4,5,8,9,11-hexaazatriphenylene-hexacarbonitrile(HAT-CN)/N,N'-di(naphthalene-lyl)-N,N'-diphenyl-benzidine(NPB)/4,4'-Bis(N-carbazolyl)-1,1'-biphenyl(CBP)/2,2',2"-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)TPBi/tris-(8-hydroxyquinoline) aluminum($Alq_3$)/LiF/Al 구조를 가진 유기 발광 다이오드 소자의 발광층에 $Ir(ppy)_3$(2% wt)을 도핑하여 소자의 특성 변화를 살펴보았다. $Ir(ppy)_3$의 두께는 5nm이고 도핑 위치는 정공 수송층과 발광층 계면의 0nm에서부터 25nm까지 5nm간격으로 도핑을 하였다. 실험 결과 소자의 효율은 도핑 위치가 정공 수송층에서 25nm떨어진 위치일 때 가장 높았고, 10nm일 때 가장 낮았다. 이는 도핑 부분의 위치가 정공 차단층에 가까워질수록 정공과 전자의 균형이 좋아지는 것이 소자 성능을 향상시키는 원인으로 추측된다.

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Curing Behavior and Morphology of DGEBA/NMA/2,4,6-tris(dimethylaminomethyl) phenol System (DGEBA/NMA/2,4,6-tris(dimethylaminomehyl)phenol 시스템의 경화거동 및 Morphology)

  • 김민영;김성호;최영선;김원호;황병선
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2001.05a
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    • pp.118-121
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    • 2001
  • The investigation of cure kinetics and morphology studies on DGEBA/PEI/Anhydride system were performed by differential scanning calorimetry and scanning electron microscopy. Autocatalystic kinetics model was applied by isothermal scan test. Ozawa method and Kissinger method was applied by temperature scan. Activation energy was 95kJ/mol for neat DGEBA/NMA, 120kJ/mol for DGEBA/PEI(10p.h.r.)/NMA. The generation of secondary phase of PEI was observed and its size was grown up by increasing contents of PEI.

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Hydroxyapatite Formation on Fluoride Bioactive Glasses coated on Alumina (알루미나에 코팅된 불화물 생체유리에의 수산화 아파타이트 형성)

  • 안현수;이은성;김철영
    • Journal of the Korean Ceramic Society
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    • v.36 no.10
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    • pp.1087-1093
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    • 1999
  • Bioglass which is one of the surface active bionmaterials has a good biocompatibility but a poor mechanical strength, In the present work therefore two types of fluoride-containing bioglasses were coated on an alumina to improve mechanical strength. Crystallization of the coating layer and the hydroxyapatite formation on the bioactive glass coatings in tris-buffer solution were studied. When bioactive glass coated alumina was heat-treated Na2CaSi3O8 crystal was formed on the layer at lower temperature while wollastonite(CaSIO3) was obtained at higher temperature. Hydroxyapatite forming rate on the coating layer with Na2CaSi3O8 crystal was delayed with SiO2 contents in glass composition. However the hydroxyapatite was developed in 20minutes regardless SiO2 contents when the coating layer crystallized into wollastonite. More amount of P3+ ions were leached out of the coating layer with wollastonite than that with Na2CaSi3O8 crystal while Na+ and Ca2+ ions were leached out more easily from the Na2CaSi3O8 crystal containing coating layer.

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Organic light emitting diodes using Iron(II) and Metal-free Phthalocyanine (Iron(II)과 Metal-free Phthalocyanine의 결정구조 변화에 따르는 유기 발광소자의 발광 특성)

  • 임은주;한우미;이정윤;김명식;이기진
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2001.07a
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    • pp.947-950
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    • 2001
  • We report the characteristics of organic light emitting diodes (OLEDS) by controlling the carrier mobility according to the crystalline of Iron(II) Phthalocyanine(Fe-Pc) and metal-free Phthalocyanine (H$_2$-Pc). In order to change the recombination zone, we controlled the hole mobility by changing the crystal structures of Fe-Pc and H$_2$-Pc. OLEDs were constructed with ITO/Fe-Pc/triphenyl-diamine (TPD)/tris-(8-hydroxyquinoline)aluminum (Alq$_3$)/Al and ITO/H$_2$-Pc/triphenyl-diamine (TPD)/tris-(8-hydroxyquinoline)aluminum (Alq$_3$)/Al. The electroluminescent properties were changed according to the heat-treatments of Fe-Pc and H$_2$-Pc. We observed that the recombination zone and the carrier mobility were changed as the higher occupied molecular orbital levels of Fe-Pc and H$_2$-Pc decreased.

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Effects of Cryoprotectants and Freezing Rates on Cryopreservation of Catfish, Silurus asotus Sperm

  • Kho, Kang Hee;Kang, Kyoung Ho
    • Journal of Aquaculture
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    • v.17 no.1
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    • pp.8-11
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    • 2004
  • Milt of the catfish was stripped into immobilizing solution containing 175 mM NaCl and 30 mM Tris at pH 7.8 and was successfully cryopreserved after a stepwise freezing procedure. After stepwise thawing, motility of spermatozoa was slightly lower than that of fresh sperm. Batches of 40-80 eggs were fertilized with cryopreserved spermatozoa, after thawing and activation in solution containing 50 mM NaCl, 20 mM Tris and HCl at pH 7.8; this resulted in 62.2% fertilization success, compared to 70.6 % with fresh sperm.

Hardening and Hydroxyapatite Formation of Bioactive Cement Prepared from Calcium Phosphosilicate Glass

  • Kim, Cheol-Young;Park, Sang-Jong
    • The Korean Journal of Ceramics
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    • v.1 no.3
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    • pp.131-136
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    • 1995
  • It has been reported that the biocement obtained by mixing $CaO-SiO_2-P_2O_5$ glass powders with ammonium phosphate solution has biocompatibility as will as high strength. The hardening mechanism and hydroxyapatite forming mechanism were discussed when $53.6%CaO_1,\; 38.1%SiO_2,\; 7.7P_2O_6,\; 0.6%CaF_2$(mole %) glass powder was reacted with ammonium phosphate solution and reacted in tris-buffer solution, respectively. High strength hardened biocement was obtained for the specimen with $CaNH_4PO_4\;H_2O$ crystal when the glass powder was mixed with ammonium phosphate solution, and hydroxyapatite crystal was rapidly formed only in the sample with $CaNH_4PO_4\;H_2O$ crystal when it was reacted in tris-buffer solution.

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Electrical Properties of Mg:Ag/tris-(8-hydroxyquinoline) Aluminum Heterointerface in Organic Light-emitting Devices

  • Choo, D.C.;Im, H.C.;Lee, D.U.;Kim, T.W.;Han, J.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 2005.07b
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    • pp.1429-1431
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    • 2005
  • Organic molecular-beam deposition of Mg:Ag thin films with a low Mg concentration on tris (8-hydroxyquinolino) aluminum $(Alq_3)$ layers at room temperature was performed to investigate the feasibility of using Mg:Ag thin films as cathode electrodes in organic light-emitting devices (OLEDs). The effective barrier height of the $Mg:Ag/Alq_3$ heterointerface, determined from current-voltage measurements, was as low as 0.23 eV. These results help improve understanding the electrical properties of the $Mg:Ag/Alq_3$ heterointerfaces in OLEDs.

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Synthesis and Nonlinear Optical Properties of 1,3,5-Tricyano-2,4,6-tris[2-(thiophen-2-yl)vinyl]benzene Derivatives

  • Cho, Bong-Rae;Kim, Young-Hoon;Son, Kyung-Wha;Khalil, Chajara;Kim, Yong-Ho;Jeon, Seung-Joon
    • Bulletin of the Korean Chemical Society
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    • v.23 no.9
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    • pp.1253-1309
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    • 2002
  • 1,3,5-Tricyano-2,4,6-tris[2-(thiophen-2-yl)vinyl]benzene derivatives have been synthesized as a new type of octupolar nonlinear optical molecules and their linear and nonlinear optical properties were determined. The λmax values increa sed with the conjugation length and as the conjugation bridge was changed from phenyl to thienyl group. For phenyl and thiophene derivatives, the b value increased with conjugation length. In contrast, the $\beta$ values of the thiophene derivatives were much smaller than the corresponding phenyl derivatives.