• Journal of Welding and Joining
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• 제12권4호
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• pp.85-101
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• 1994

Effect of Cr, Cu and Ni metal powders addition on the alloyed layer of aluminum alloy (AC2B) has been investigated with the plasma transferred arc (PTA) overlaying process. The overlaying conditions were 125-200A in plasma arc current, 150mm/min in process speed and 5-20g/min in powder feeding rate. Main results obtained are summarized as follows: 1) It was made clear that formation of thick surface alloyed layer on aluminum alloy is possible by PTA overlaying process. 2) The range of optimum alloying conditions were much wider in case of Cu and Ni powder additions than the case of Cr powder addition judging from the surface appearance and the bead macrostructure. 3) Alloyed layer with Cu showed almost the homogeneous microstructure through the whole layer by eutectic reaction. alloyed layers with Cr and Ni showed needle-like and agglomerated microstructures, the structure of which has compound layer in upper zone of bead by peritectic and eutectic-peritectic reactions, respectively. 4) Microconstituents of the alloyed layer were analyzed as A1+CrA $l_{7}$ eutectics, C $r_{2}$al sub 11/, CrA $l_{4}$, C $r_{4}$A $l_{9}$ and C $r_{5}$A $l_{*}$ 8/ for Cr addition, Al+CuA $l_{2}$(.theta.) eutectics and .theta. for Cu addition, and Al+NiA $l_{3}$ eutectics. NiA $l_{3}$, N $i_{2}$A $l_{3}$ and NiAl for Ni addition. 5) Concerning defect of the alloyed layer, many blow holes were seen in Cr and Ni additions although there was lesser in Cu addition. Residual gas contents in blow hole for Cu and Ni alloyed layer were confirmed as mainly $H_{2}$ and a littie of $N_{2}$ Cracking was observed in compound zone of the alloyed layer in case of Cr and Ni addition but not in Cu alloyed layer.r.r.

• 대한화학회지
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• 제44권3호
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• pp.207-211
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• 2000

Tween80 미셀용액에서 착화제로서 APDC틀 이용하여 Ni(II)를 정량하는 방법에 대해 연구하였다. Ni(PDC)$_2$ 착물의 홉수 스펙트럼 chloroform에서 보다는 Tween80에서 더 좋은 모양과 더 좋은 감도를 보여 주었다. Ni(PDC)$_2$ 착물은 pH 7.0에서 그리고 100분 정도까지 매우 안정하였으며, APDC를 Ni(II)의 몰수의 10배 이상 넣어 주면 정량적으로 착물이 형성되었다. Tween80의 농도는 0,1%가 적절하였고,0.1% Tween80 용액에서 Ni(PDC)$_2$ 착물의 검정곡선은 좋은 직선성(R2=0.9955)을 보여주었다. 이 분석법의 검출한계와 정량한계는 각각 0.09 ${\mu}g$/mL와 0.28${\mu}g$/mL이었으며, 강물시료에 적용한 회수율은 100% 보다 조금 크게 나타났다. 비록 여러 금속이온들이 방해를 하지만, 실제시료에 들어있는 Ni(II)을 정량하는데 이용할 수 있을 것이다.

• 한국세라믹학회지
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• 제28권4호
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• pp.305-314
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• 1991

This study was conducted to research the formation and the color development of NiO-ZnO-Fe2O3-TiO2-SnO2 system for the purpose of synthesizing the spinel pigments which are stable at high temperature. After preparing ZnO-Fe2O3 as a basic composition, {{{{ chi }}NiO.(l-{{{{ chi }})ZnO.Fe2O3 system, {{{{ chi }}NiO.(l-{{{{ chi }})ZnO.TiO2 system, and {{{{ chi }}NiO.(l-{{{{ chi }})ZnO.SnO2 system were prepared with {{{{ chi }}=0, 0.2, 0.5, 0.7, 1 mole ratio respectively. The manufacturing was carried out at 128$0^{\circ}C$ for 30 minutes. The reflectance measurement and the X-ray analysis of these specimens were carried out and the results were summarized as follows. 1. In the specimens which included NiO, it was difficult for the spinel structure to be formed. 2. As increasing the contents of NiO and Fe2O3, all the groups which were yellow or green colored changed to brown. 3. NiO-ZnO-Fe2O3 system and NiO-ZnO-TiO2 system formed the spinel structure and the illmenite structure appeared in NiO-TiO2 system.

• 청정기술
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• 제23권1호
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• pp.27-33
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• 2017

본 연구에서는 중금속 7종(Cu, Cd, Cr, As(III), As(V), Zn, Ni) 및 나노입자 5종(CuO, ZnO, NiO, $TiO_2$, $Fe_2O_3$)에 대한 독성을 수계 대표 생물종인 녹조류 Chlorella vulgaris를 이용한 생물검정법으로 평가하였다. 조류에 미치는 영향은 흡광도, 클로로필 및 개체수 측정에 대한 결과를 통합하여 평가하였다. 중금속의 통합결과독성($TEC_{50}$) 순서는 Cr ($0.7mgL^{-1}$) > Cu ($1.7mgL^{-1}$) > Cd ($3.2mgL^{-1}$) > Zn ($3.9mgL^{-1}$) > Ni ($13.2mgL^{-1}$) > As(III) ($17.8mgL^{-1}$) ${\gg}$ As(V) (> $1000mgL^{-1}$)로 나타났다. 중금속은 측정종말점에 따라 일부 상이한 민감도와 독성이 조사되었다. 나노입자의 독성($TEC_{50}$) 순서는 ZnO ($2.4mgL^{-1}$) > NiO ($21.1mgL^{-1}$) > CuO ($36.6mgL^{-1}$) > $TiO_2$ ($62.5mgL^{-1}$) > $Fe_2O_3$ ($82.7mgL^{-1}$)로 나타났다. 나노입자는 측정종말점간에 비슷한 민감도와 독성을 보였다. 따라서 오염물의 독성을 평가하기 위해서 단일 방법에 의한 결과보다는 다양한 측정종말점의 통합결과에 근거한 접근이 적절할 것이다.

• 한국전기화학회:학술대회논문집
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• 한국전기화학회 2001년도 연료전지심포지움 2001논문집
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• pp.237-242
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• 2001

용융탄산염 연료전지에서 분리판으로 사용되는 316L 스테인리스 스틸의 내식성을 향상시키기 위해 Ni과 Al을 전기도금법에 의해 코팅하였으며 열처리를 통해 스테인리스 스틸표면에 $Ni_2Al_3$, NiAl 등의 금속간화합물을 형성시켰다. $62mol\%Li_2CO_3-38mol\%K_2CO_3$ 전해질 내에서 100시간 동안 침지실험을 수행한 결과 Al의 도금두께가 $10{\mu}m$ 이상인 경우에는 내식성이 상당히 향상되었음을 확인하였다.

• Bulletin of the Korean Chemical Society
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• 제29권10호
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• pp.1905-1910
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• 2008

The reaction of 3,14-dimethyl-2,6,13,17-tetraazatetracyclo[16.4.0$0^{1.18}.0^{7.12}$]docosane ($L^1$) with formaldehyde in warm methanol yielded 3,14-dimethyl-2,6,13,17-tetraazatetracyclo[16.4.$1^{2.6}.0^{1.18}.0^{7.12}$]tricosane ($L^7$) containing one 1,3-diazacyclohexane subunit. In methanol, $L^7$ readily reacts with $Cu^{2+}$ ion to form [$CuL^7(H_2O)$]$^{2+}$ which is extremely inert against methanolysis. In the solution containing $Ni^{2+}$ ion, however, $L^7$ reacts with methanol to yield [$NiL^3$]$^{2+}$ ($L^3$ = 2-(methoxymethyl)-5,16-dimethyl-2,6,13,17-tetraazatricyclo[16.4.$0^{1.18}.0^{7.12}$]- docosane), in which one N-$CH_2OCH_3$ pendant arm is appended. The copper(II) complex [$CuL^7(H_2O)$]- $(ClO_4)_2{\cdot}3H_2O\;(I{\cdot}3H_2O)$ has a severely distorted trigonal bipyramidal coordination geometry with a 4-5- 6-5 chelate ring sequence. The crystal structure of [$NiL^3$]$(PF_6)_2{\cdot}2H_2O$ (IIb) shows that the N-$CH_2OCH_3$ pendant arm is not coordinated to the metal ion in the solid state. In various solvents (S), however, the nickel(II) complex exists as a mixture of [$NiL^3$(S)]$^{2+}$, in which the N-$CH_2OCH_3$ group as well as S is coordinated to the metal ion, and [$NiL^3$]^{2+}.

• 한국재료학회지
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• 제17권8호
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• pp.420-424
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• 2007

Precipitation behavior has been studied in NiTi-based ordered alloy using transmission electron microscopy. The hardness after solution treatment is high in NiTi alloy suggesting the large contribution of solid solution strengthening in this alloy system. However, the amount of age hardening is not large as compared to the large microstructural variations during aging. At the beginning of aging, the $L2_1-type$ $Ni_2AlTi$ precipitates keep a lattice coherency with the NiTi matrix. By longer periods of aging $Ni_2AlTi$ precipitates lose their coherency and change their morphology to the globular ones surrounded by misfit dislocations. Misfit dislocations, which are observed on {100} planes of H-precipitates have the Burgers vector of a <100> with a pure edge type. The lattice misfits of $NiTi-Ni_2AlTi$ system is estimated from the spacings of misfit dislocations to be 1.3% at 1273 K. The lattice misfits decrease with increasing aging temperature in this system.

• 한국결정학회지
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• 제8권2호
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• pp.124-126
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• 1997

[Ni(L)](ClO4)2(L:3,5,10,12-tetramethly-1,4,8,11-tetraazacyclotetradecane), C14H32Cl2N4NiO8, 착물은 NiN4 평면4각구조를 가지며 열력학적으로 가장 안정한 trans-III구조를 하고 있다.

• 대한화학회지
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• 제35권5호
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• pp.527-533
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• 1991

포름알데히드, 테트라아민류 및 디아민류의 Ni(II) 또는 Cu(II) 이온 존재하에서의 주형축합반응으로부터 헥사아자 거대세고리 및 거대네고리 리간드의 평형사각형 착물 $[M(L)]^{2+}$(M = Ni(II) 또는 Cu(II); L = 4-메틸-1,3,6,8,11,14-헥사아자트리시클로[12,2,1,$1^{8,11}$]옥타데칸(C), 1,3,10,12,15,18-헥사아자테트라시클로[6,2,1,$1^{12,15},0^{4,9}]$도코산(D), 4-메틸-1,3,6,8,12,15-헥사아자트리시클로[13,3,1,$1^{8,12}$]에이코산(F) 또는 1,3,10,12,16,19-헥사아자테트라시클로[l7,3,1,$1^{12,16},0^{4,9}]$테트라코산(G))를 합성하였다. 이들 착물의 여섯 원자 킬레이트고리에는 두개 씩의 1,3-디아자시클로펜탄 도는 1,3-디아자시클로헥산 고리가 있다. C와 F의 착물의 다섯원자 킬레이트고리에는 메틸기가 그리고 D와 G의 경우에는 시클로헥산 고리가 있다. 이들 니켈(Ⅱ) 및 구리(Ⅱ) 착물의 합성과 특성, 그리고 수용액에서의 $[Ni(L)]^{2+}+2H_2O{\rightleftharpoons}[Ni(L)(H_2O)_2]^{2+}$의 평형에 미치는 리간드 구조의 영향이 논의 된다.

• 대한화학회지
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• 제43권2호
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• pp.28-231
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• 1999