• 대한화학회지
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• 제32권5호
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• pp.428-435
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• 1988

Isonitrosoacetylacetone 및 여러가지 디아민으로 부터 유도된 리간드와의 니켈(Ⅱ) 및 팔라듐(Ⅱ) 착물들, 즉, $Ni(IAA)_2-en$, $Ni(IAA)_2-pn$, $Ni(IAA)_2-tn$, Pd(IAA)$_2$-en, PdCl(IAA)-pn, 그리고 Pd(IAA)$_2$-tn을 합성하였다. 여기서 (IAA)$_2$-en, (IAA)$_2$-pn, (IAA)$_2$-tn, 그리고 (IAA)-pn 은 각각 N,N'-enthylenbis(isonitrosoacetylacetone imine), N,N'-propylenebis(isonitrosoacetylacetone imine), N,N'-trimethylenebis(isonitrosoacetylacetone imine), 그리고 N-(2-aminopropyl)isonitrosoacetylacetone imine 을 표시한다. 합성된 이들 니켈(Ⅱ) 및 팔라듐(Ⅱ) 착물들의 원소분석, 적외선 스펙트럼, 핵자기공명스펙트럼, 그리고 전자스펙트럼등을 측정한 결과, $Ni(IAA)_2$-tn 및 Pd(IAA)$_2$-en에서 리간드의 한 isonitroso 기는 질소원자를 통하여 금속이온에 배위되어 5각형 고리를 이루고, 다른 isonitroso기는 산소원자를 통하여 금속이온에 배위되어 6각형 고리를 이룬다. 그리고, $Ni(IAA)_2$-en, Ni(IAA)$_2$-pn, 그리고 Pd(IAA)$_2$-tn에서 리간드의 두개의 isonitroso기는 모두 질소원자를 통하여 금속이온에 배위되어 5각형 고리를 이룬다. 한편, PdCl(IAA)-pn 은 팔라듐과 한분자의 isonitrosoacetylacetone 및 propylenediamine의 반응으로 생성된다.

• 한국염색가공학회지
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• 제22권1호
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• pp.77-82
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• 2010

Highly conductive yarn was successfully obtained using electroless nickel plating method with palladium activation. In the presence of palladium seed on surface of fibers as a catalyst, continuos nickel layer produced on surface of fibers by reducing $Ni${2+}$ ion in the electroless plating bath to $Ni^0$. It was found that the Pd-activation using $SnCl_2$ and $PdCl_2$ to deposit palladium seeds on the surface of fibers plays a key role in the subsequent electroless plating of nickel. It also found that electroless nickel plating on the fibers can induce the nickel-plated $ELEX^{(R)}$ fibers to improve the electrical conductivity of the fibers. The thickness of nickel coating layer on the Pd-activated $ELEX^{(R)}$ fibers and specific conductivity of the fiber were increased through electroless plating time. The temperature of nickel plating bath was very effective to enhance the nickel deposition rate.

• Bulletin of the Korean Chemical Society
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• 제22권8호
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• pp.801-806
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• 2001

A study has been carried out on the separation of gold, iridium, palladium, rhodium, ruthenium and platinum in chromite samples and their quantitative determination using inductively coupled plasma atomic emission spectrometry (ICP-AES). The dissolution condition of the minerals by fusion with sodium peroxide was optimized and chromatographic elution behaviour of the rare metals was investigated by anion exchange chromatography. Spectral interference of chromium, a matrix of the minerals, was investigated on determination of gold. Chromium interfered on determination of gold at the concentration of 500 mg/L and higher. Gold plus trace amounts of iridium, palladium, rhodium and ruthenium, which must be preconcentrated before ICP-AES was separated by anion exchange chromatography after reducing Cr(Ⅵ) to Cr(III) by H2O2. AuCl4- retained on the resin column was selectively eluted with acetone- HNO3-H2O as an eluent. In addition, iridium, palladium, rhodium and ruthenium remaining on the resin column were eluted as a group with concentrated HCl. However, platinum was eluted with concentrated HNO3. The recovery yield of gold with acetone-HNO3-H2O was 100.7 ${\pm}2.0%$, and the yields of palladium and platinum with concentrated HCl and HNO3 were 96.1 ${\pm}1.8%$ and 96.6 ${\pm}1.3%$, respectively. The contents of gold and platinum in a Mongolian chromite sample were 32.6 ${\pm}$ 2.2 ${\mu}g$/g and 1.6 $\pm$ 0.14 ${\mu}g$/g, respectively. Palladium was not detected.

• 대한화학회지
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• 제35권6호
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• pp.667-672
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• 1991

팔라듐(Ⅱ) 이온의 존재하에서 isonitrosobenzoylacetone(IBA)과 diamine (ethylenediamine(en) 또는 trimethylenediamine(tn))으로부터 새로운 착물들인 N-(2-aminoethylisonitrosobenzoylacetone imino) chloropalladium(Ⅱ), PdCl(IBA)-en, 및 N-(3-aminopropylisonitrosobenzoylacetone imino) chloropalladium(Ⅱ), PdCl (IBA)-tn을 합성하고 이들 착물의 구조를 조사하였다. 그 결과 이들 착물은 모두 사각평면구조를 가지며 하나의 디이민리간드와 염소이온이 금속에 배위되어 있음을 알 수 있었다. 여기서 디이민리간드는 isonitrosobenzoylacetone과 diamine이 1:1로 반응하여 생성되었으며, isonitroso (=N-O), C=N 및 $NH_2$기의 세개의 질소원자들을 통하여 금속에 결합하고 있는 세자리 리간드임을 알 수 있었다.

• 한국물환경학회지
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• 제31권5호
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• pp.468-475
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• 2015

Various methods to degrade explosives efficiently in natural soil and water that include trinitrotoluene (TNT) have been studied. In this study, TNT in water was degraded by reduction with palladium (Pd) catalyst impregnated onto alumina (henceforth Pd-Al catalyst) and formic acid. The degradation of TNT was faster when the temperature of water was high, and the initial TNT concentration, pH, and ion concentration in water were low. The amounts of Pd-Al catalyst and formic acid were also important for TNT degradation in water. According to the experimental results, the degradation constant of TNT with unit mass of Pd-Al catalyst was $8.37min^{-1}g^{-1}$. The degradation constant of TNT was higher than the results of previous studies which used zero valent iron. 2,6-diamino-4-nitrotoluene and 2-amino-4,6-dinitrotoluene were detected as by-products of TNT degradation showing that TNT was reduced. The by-products of TNT were also completely degraded after reaction when both Pd-Al catalyst and formic acid existed. Even though there are several challenges of Pd-Al catalyst (e.g., deactivation, poisoning, leaching, etc.), the results of this study show that TNT degradation by Pd-Al catalyst and formic acid is a promising technique to remediate explosive contaminated water and soil.

• 대한화학회지
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• 제67권6호
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• pp.429-440
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• 2023

1,1-Dialkyl-2,5-bis(trimethylsilylethynyl)-3,4-diphenylsiloles (R=Et, i-Pr, n-Hex; 3a-c) were prepared and utilized as anode active materials for lithium-ion batteries; 3a was also used as a filler for the solid-state electrolytes (SSE). Siloles 3a-c were prepared by substitution reactions in which the two bromine groups of 1,1-dialkyl-2,5-dibromo-3,4-diphe- nylsiloles, used as precursors, were substituted with trimethylsilylacetylene in the presence of palladium chloride, copper iodide, and triphenylphosphine in diisopropylamine. Among siloles 3a-c, 3a had the best electrochemical properties as an anode material for lithium-ion batteries, including an initial capacity of 758 mAhg^-1 (0.1 A/g), which was reduced to 547 mAhg^-1 and then increased to 1,225 mAhg^-1 at 500 cycles. A 3a-composite polymer electrolyte (3a-CPE) was prepared using silole 3a as an additive at concentrations of 1, 2, 3, and 4 wt.%. The 2 wt.% 3a-CPE composite afforded an excellent ionic conductivity of 1.09 × 10^-3 Scm^-1 at 60℃, indicating that silole 3a has potential applicability as an anode active material for lithium-ion batteries, and can also be used as an additive for the SSE of lithium-ion batteries.

• The Journal of Advanced Prosthodontics
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• 제7권1호
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• pp.56-61
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• 2015

PURPOSE. The purpose of this study was to evaluate the effects of the surface treatment and shape of the dental alloy on the composition of the prosthetic work and its metallic ion release in a corrosive medium after casting. MATERIALS AND METHODS. Orion Argos (Pd-Ag) and Orion Vesta (Pd-Cu) were used to cast two crowns and two disks. One of each was polished while the other was not. Two as-received alloys were also studied making a total of 5 specimens per alloy type. The specimens were submersed for 7 days in a lactic acid/sodium chloride solution (ISO standard 10271) and evaluated for surface structure characterization using SEM/EDAX. The solutions were quantitatively analysed for the presence of metal ions using ICP-MS and the results were statistically analysed with one-way ANOVA and a Tukey post-hoc test. RESULTS. Palladium is released from all specimens studied (range $0.06-7.08{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$), with the Pd-Cu alloy releasing the highest amounts. For both types of alloys, ion release of both disk and crown pairs were statistically different from the as-received alloy except for the Pd-Ag polished crown (P>.05). For both alloy type, disk-shaped pairs and unpolished specimens released the highest amounts of Pd ions (range $0.34-7.08{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$). Interestingly, in solutions submerged with cast alloys trace amounts of unexpected elements were measured. CONCLUSION. Shape and surface treatment influence ion release from dental alloys; polishing is a determinant factor. The release rate of cast and polished Pd alloys is between $0.06-0.69{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$, which is close to or exceeding the EU Nickel Directive 94/27/EC compensated for the molecular mass of Pd ($0.4{\mu}g{\cdot}cm^{-2}{\cdot}week^{-1}$). The composition of the alloy does not represent the element release, therefore we recommend manufacturers to report element release after ISO standard corrosion tests beside the original composition.

• 한국재료학회지
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• 제11권2호
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• pp.76-81
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• 2001

전자산업 폐기물의 산침출 용액으로부터 전해채취법에 의해 Au와 Pd를 선택적으로 회수하기 위하여, 염산수용액 중에서 Au와 Pd의 전기화학적 거동을 voltammetry방법에 의해 조사하였다. Au단독 전해욕에서 Au의 환원전위는 약 800mV이었고 환원한계전류는 약 470mV에서 나타났으며, Pd 단독 전해욕에서 Pd의 환원전위는 약 500mV이었고 환원한계전류는 약 150mV에서 나타났다. 그러나, Au-Pd혼합 전해용액에서, Au의 환원전위 및 환원한계전위 값은 전해욕 중 Pd의 농도가 증가함에 따라 감소하였고, Au와 Pd의 환원한계전위 값은 Au-Pd 전해욕 중 Pd 전해용액의 함유량이 30vo1%일 때 가장 가까운 값을 나타내었다

• 한국수소및신에너지학회논문집
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• 제12권4호
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• pp.257-265
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• 2001

Placing a hydrogen conducting, methanol impermeable metallic barrier like palladium (Pd) is a well-known method for preventing methanol crossover through solid polymer electrolyte for direct methanol fuel cells (DMFC). Applying a bias potential between the anode and the barrier can further develop this concept so that the hydrogen transfer rate is enhanced. Since hydrogen diffuses in Pd as atomic form while it moves through nafion electrolyte as ion, it has to be reduced or oxidized whenever it passes the interface formed by Pd and the electrolyte. We performed experiments to measure the hydrogen transport through the Pd membrane placed in Nafion electrolyte of hydrogen/oxygen fuel cell (PEMFC). Applying a bias potential between the hydrogen electrode of the cell and the Pd membrane facilitated the hydrogen passage through the Pd membrane. The results show that the cell current measured with the Pd membrane placed reached almost 40 % the value measured with the cell without Pd membrane. It was found that the current flown through the bias path is only a few percent of the cell current.

• Bulletin of the Korean Chemical Society
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• 제12권5호
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• pp.499-504
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• 1991

EPR spectra of the high $T_c$ superconductor $YBa_2Cu_3O_{7-y}$ (YBCO) doped with $Pd^{2+} or Zn^{2+}$ have been measured at several temperatures and dopant concentrations. The spectral intensity of $YBa_2({Cu_{1-x}}{Pd_x})_3O_{7-y}$ is proportional to the dopant concentration. The behavior of $YBa_2(Cu_{1-x}Zn_x)_3O_{7-y}$ is quite different: the spectral intensity remains almost constant up to x=0.10 and then increases rapidly above x=0.10. The results are interpreted in terms of localized and antiferromagnetically spin-paired d holes in both CuO chain and planes. The $Pd_{2+}$ ion substitutes on the CuO chain consisting of "CuOCu dimers", and a $Cu_{2+}$ ion with an unpaired spin is gene rated for each $Pd_{2+}$ ion substituted. On the other hand, $Zn_{2+}$ substitutes on the CuO planes, and all or most of the spins in the two-dimensional plane manage to pair up in the region of low dopant concentration. When the dopant concentration exceeds a certain limit, it becomes more difficult for the spins to find partners, and the number of unpaired spins increases rapidly with increasing dopant concentration. The $Zn_{2+}$ ion is more effective than the $Pd_{2+}$ ion in suppressing the superconductivity of YBCO. This is attributed to the fact that $Zn_{2+}$ substitutes on the CuO planes which are mainly responsible for the superconductivity, while $Pd_{2+}$ substitutes on the CuO chain which is of secondary importance in the superconductivity.