• 제목/요약/키워드: Aluminum compound

검색결과 159건 처리시간 0.026초

알루미늄 유도 결정화를 이용한 대면적 다결정 Si 가상 기판 성장 전략 (A Strategy on the Growth of Large Area Polycrystalline Si Virtual Substrate Using Al-Induced Crystallization)

  • 김도현;박광욱
    • 한국전기전자재료학회논문지
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    • 제37권1호
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    • pp.26-35
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    • 2024
  • Aluminum-induced crystallization (AIC) as a route to reduce the fabrication cost and to obtain polycrystalline Si (p-Si) thin-film of large grain size is a promising alternative of single-crystalline (s-Si) substrate or p-Si thin-film obtained by conventional methods such as solid phase crystallization (SPC) and laser-induced crystallization (LIC). As the AIC process occurs at the interface between a-Si and Al thin-films, there are various process and interface parameters. Also, it directly means that there is a certain parametric window to obtain p-Si of large grain size having uniform crystal orientation. In this article, we investigate the effect of the various process and interface parameters to obtain p-Si of large grain size and uniform crystal orientation from the literature review. We also suggest the potential use of the p-Si as a virtual substrate for the growth of various compound semiconductors in a form of low-dimension as well as thin-film as a way for their monolithic integration on Si.

알루미늄 화합물이 흰쥐의 혈청 효소 활성도에 미치는 영향 (Effects of Aluminum Compounds on Enzyme Activities in the Serum of Rat)

  • 김중만;백승화;한성희;신용서;윤태헌
    • 한국식품과학회지
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    • 제28권5호
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    • pp.801-805
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    • 1996
  • 알루미늄 화합물이 흰쥐의 효소활성에 미치는 영향을 알아보고자 흰쥐(Sprague-Dawley계 male) 75마리를 5개 그룹 즉, 대조군, $250\;ppm\;AlCl_3\;500\;ppm\;AlCl_3,\;250\;ppm\;Al_2(SO_4)_3,\;500\;ppm\;Al_2(SO_4)_3$로 나누어 2주동안 투여하여 asparate amino transaminase, alanine amino transminase, lactate dehydrogenase, 그리고 cholinesterase의 변화를 조사하였다. 체중은 대조군에 비하여 $Al_2(SO_4)_3$ 투여군은 2.82-6.16% 증가한 반면에 $AlCl_3$ 투여군에서는 0.53-3.35%로 감소하였다. 효소활성은 대조군에 비하여 $AlCl_3$ 또는 $Al_2(SO_4)_3$ 투여후에 AST는 0.68-9.97%, 21.04-24.79%, LDH는 29.43-57.56%, 74.60-29.33% 증가하였으나, ALT는 12.69-25.42%, 24.32-39.62%로 각각 감소하였다. ChE는 대조군에 비하여 $Al_{2}(SO_4)_3$ 투여군은 28.0-12.73% 증가하였으나 $Al_2(SO_4)_3$ 투여군은 3.93-14.48% 감소하였다.

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송전선로 폴리머애자 공사용 장비 개발 (Development of Working Platform for the Polymer Insulator String)

  • 민병욱;위화복;방항권;최한열;백수곤;박재웅
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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    • pp.438-439
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    • 2006
  • Porcelain insulators have generally been used in Korea to insulate a transmission line from the tower, and a highly polymerized compound polymer insulator which has superior stain proof characteristics, has also been used widely. Currently, a worker rides on the suspension insulator string for installation on towers and conductors but in case of polymer insulators, this will pollute and scratch the housing result in durability reduction by deterioration and corona. This study developed a high strength aluminum compound metal lauder designed to work on polymer insulators without riding, and a clamp type connecting device and safety gear for easy installation on the tower and conductor. These polymer insulator work device can be used for 154kV and 345kV polymer insulators through a strength and load test to secure safety. This paper presents field usage.

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Ion Beam을 이용한 사파이어($Al_2O_3$) 표면개질 및 금(Au) 박막증착: 접합성 향상 및 접학기구에 대한 연구 (Ion beam induced surface modifications of sapphire and gold film deposition: studies on the adhesion enhancement and mechanisms)

  • 박재원;이광원;이재형;최병호
    • 한국진공학회지
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    • 제8권4B호
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    • pp.514-518
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    • 1999
  • Gold (Au) is not supposed to react with sapphire(single crystalline ) under thermodynamic equillibrium, therefore, a strong adhesion between these two dissimilar materials is not expected. However, pull test showed that the gold film sputter-deposited onto annealed and pre-sputtered sapphire exhibited very strong adhesion even without post-deposition annealing. Strongly and weakly adhered samples as a result of the pull testing were selected to investigate the adhesion mechanisms with Auger electron spectroscopy. The Au/ interfaces were analyzed using a new technique that probes the interface on the film using Auger electron escape depth. It revealed that one or two monolayers of Au-Al-O compound formed at the Au/Sapphire interface when AES in the UHV chamber. It showed that metallic aluminum was detected on the surface of sapphire substrates after irradiating for 3 min. with 7keV Ar+ -ions. These results agree with TRIM calculations that yield preferential ion-beam etching. It is concluded that the formation of Au-Al-O compound, which is responsible for the strong metal-ceramic bonding, is due to ion-induced cleaning and reduction of the sapphire surface, and the kinetic energy of depositing gold atoms, molecules, and micro-particles as a driving force for the inter-facial reaction.

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소목 천연 염색에 관한 연구 II -잿물의 매염효과에 대하여- (A Study on Natural Dyeing using Caesalpinia sappan -Mordanting Effect of Rice Straw Ash Solution-)

  • 권민수;최인려;김종준;전동원
    • 복식문화연구
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    • 제12권6호
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    • pp.908-917
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    • 2004
  • In the previous article, the effect of aluminum compounds on the mordanting of the Caesalpinia sappan L. dyeing was studied. According to the type of the compound, the effect on the dyeing was found to be different even if $Al^{3+}$ ion was present in the molecular structure of the compound. It was postulated that there would be complex effects other than the effects based on the purified Al compounds only, since there are some amount of compounds hard to neglect. In order to reproduce the traditional dyeing practice, rice straw ash solutions were prepared as mordanting agents. The pH values of the solution baths were 4, 5, 6, 9, and 11 in order to investigate the pH effect on the color development by adding appropriate amount of Schizandra chinensis extract solution. The inherent dyeing properties were evaluated by the analysis of color difference, air permeability, the characteristics developed by pre-mordanting, post-mordanting, or simultaneous mordanting methods.

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Effect of the thickness of an emitting zone by the thin alkali compound films for highly efficient $Alq_3-based$ OLEDs

  • Kim, Young-Min;Lee, Joo-Won;Park, Jung-Soo;Kim, Jai-Kyeong;Sung, Man-Young;Ju, Byeong-Kwon;Jang, Jin
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.II
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    • pp.1306-1309
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    • 2005
  • Highly efficient and bright organic light-emitting diodes (OLEDs) have been realized using the thin alkali compound films (TACFs) at the interface between an emitting layer and an electron transporting layer with conventional organic layers. By comparing the performance of the device as a function of position with the TACFs, we propose the optimal position of the TACFs in the tris-(8-hydroxyquinoline) aluminum (Alq3). A device with the ACFs showed high luminance of over 12 500 cd/m2, luminance efficiency of more than 12 cd/A, and power efficiency of more 4.5 lm/W, respectively.

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Squeeze Casting에 의한 SiC 입자강화 Al합금기 복합재료의 미세조직 특성 (Microstructural Characteristics of SiC Particle Reinforced Aluminum Alloy Composite by Squeeze Casting)

  • 김석원;우기도;한상원
    • 한국주조공학회지
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    • 제15권6호
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    • pp.566-573
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    • 1995
  • In this study, the microstructural characteristics such as primary silicon, eutectic silicon, $SiC_p$ dispersion behavior, compound amount and Si solubility in $Al/SiC_p$ composite fabricated by the squeeze casting under various conditions were investigated systematically. As applied pressure(MPa) increases, cooling rate and compound amount are increased. In gravity casting, the cooling rate of hypereutectic composite is slower than of hypoeutectic composite by exothermic reaction of primary Si crystallization. But the cooling rate of hypereutectic composite is faster than that of hypoeutectic composite fabricated by same applied pressure, because amount of primary Si crystallization in hypereutectic composite was decreased, on the contrary, primary ${\alpha}-Al$ in hypoeutetic composite was increased due to increase of Si solubility in matrix by applied pressure. The crystalized primary silicon in hypereutectic composite fabricated by squeeze casting become more fine than that in non-pressure casting This is because mush zone became narrow due to increase of Si content of eutectic composition by pressure and time for growth of primary silicon got shorter according to applied pressure. It is turned out that eutectic temperature and liquidus are decreased by the increasing of squeeze pressure in all the composite due to thermal unstability of matrix owing to increasing of Si solubility in matrix by the increasing of applied pressure, as indicated in thermal anaiysis(DSC) results.

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기계적 합금화에 의한 Al-25at%Nb 혼합분말의 상형성 거동 (Phase Formation Behavior of Mechanical Alloyed Al-25at% Nb Powder Mixtures)

  • 이상호;김동관;이진형
    • 한국재료학회지
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    • 제5권8호
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    • pp.997-1004
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    • 1995
  • 기계적 합금화(mechanical alloying:MA) 방법에 의해 원소 Nb와 Al의 혼합분말로부터 금속간 화합물 NbA1₃와 비정질상을 얻었다. 혼합분말의 조성은 Nb-45wt%Al(75at%Al)으로 하였으며, 기계적 합금화는 고에너지 SPEX8000 mixer/mill을 사용하여 72시간까지 행하였다. 얻어진 분말은 XRD, DTA, SEM 및 TEM으로 분석했다. 기계적 합금화 초기 단계의 분말은 층상 구조를 나타냈고, 정상상태에 도달하였을 때는 분말 내에서 원소 Nb와 Al이 균일하게 분포되어 있었다. 4시간 기계적 합금화를 하였을 때 금속간 화합물 NbA1₃가 형성되었다. 기계적 합금화된 분말들은 안정한 NbA1₃형성 및 응력 완화에 해당되는 600℃ 근처에서 큰 발열 peak을 나타냈다.

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아시아티코사이드로부터 메칠 2${\beta},\;3{\beta}$-에폭시-23- 히드록시우르스-12-엔-28-오애이트의 합성 및 이의 환원적 에폭시환 개열반응 (Formation of Methyl 2${\beta},\;3{\beta}$-Epoxy-23-hydroxyurs-12-en-28-oate from Asiaticoside and Its Reductive Epoxide Ring Opening Reaction)

  • 주상섭;임두연;서성기;남태규;박형근;김희두;김창민;이민희;백형근;이민정;정영훈
    • 약학회지
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    • 제42권5호
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    • pp.500-506
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    • 1998
  • Steroidal 2${\beta},\;3{\beta}$--epoxy compound was prepared from asiaticoside via six steps and reduced regioselectively with lithium aluminum hydride. Epoxide ring opening furnished 9 as a sole product at reflux condition through axial hydride attack at C-3.

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Synthesis and Characterization of Aluminum and Gallium Complexes of Heterocyclic Thiosemicarbazones. Crystal Structures of $Me_2M[SC_4H_3CHNNC(S)SCH_3$] (M=Al, Ga)

  • 강영진;유병우;강상욱;고재정;강승주
    • Bulletin of the Korean Chemical Society
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    • 제19권1호
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    • pp.63-67
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    • 1998
  • The synthesis and characterization of the monomeric group 13 heterocyclic thiosemicarbazone complexes $Me_2M[SC_4H_3CHNNC(S)SCH_3]$ (M=Al (2), Ga (3)) are described. Compounds 2-3 were prepared using $MMe_3$ (M=Al, Ga) in toluene with 2-thiophenecarboxaldehyde-S-methyldithiocarbazat e under anaerobic conditions. These complexes have been characterized by $^1H\;NMR,\; ^{13}C\; NMR$, elemental analyses, and single-crystal X-ray diffraction. 2 crystallizes in the monoclinic space group $P2_1/c$ with unit cell parameters a=10.2930(5) Å, b=18.564 (1) Å, c=7.3812(6) Å, V=1347.9(2) Å3, $D_{calc}=1.342\; gcm^{-3}$ for Z=4, 9281 reflections with $I_o<3{\sigma}\;(I_o),$ R1=0.0500 and wR2=0.0526. 3 crystalizes in the orthorhombic space group $P_{bca}$ with unit cell parameters a=13.340(3) Å, b=19.9070(5) Å, c=11.3690(2) Å, $V=2673.88(9)\;{\AA}^3$, $D_{calc}=1.511\; gcm^{-3}$ for Z=8, 17004 reflections with $I_o>3{\sigma}\;(I_o),$, R1=0.0480 and wR2=0.0524. Compound 3 is a monomeric gallium compound with a weak interaction between the pendant thiophene and the gallium center.