• Bulletin of the Korean Chemical Society
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• v.7 no.5
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• pp.385-388
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• 1986

The reaction of cupric nitrate trihydrate with S-2-pyridyl thioates in acetonitrile was studied. The major products were the corresponding carboxylic acids and $[Cu(NO_3)(C_5H_4NS)(C_5H_5NS$)] (Complex A). Sometimes $[Cu(NO_3)(C_5H_4NS)(H_2O$)] was also obtained in addition to Complex A. When Complex A was recrystallized in dimethylsulfoxide, $[Cu(NO_3)(C_5H_4NS)(C_5H_5NS)$ {$(CH_3)_2SO$}$_2]{\cdot}2H_2O$ was crystallized. The structures of these copper complexes and the role of cupric nitrate in the hydrolysis of S-2-pyridyl thioates are discussed.

• Korean Chemical Engineering Research
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• v.46 no.6
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• pp.1069-1074
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• 2008

In this work, we made a study for the 3D SAM formation of octanethiol, decanethiol, and dodecanethiol on copper nanoparticles and we verified stability of the copper particle depending on the ratio of dodecanethiol to copper. The reaction was performed in a one-phase system under nitrogen atmosphere and the thiolated copper particles could be obtained by centrifugation. We could confirm that the nanoparticles consisted of a spherical shape of 3~6 nm from TEM images. FT-IR, XPS and TGA results showed that alkanethiols were chemisorbed via thiol group and the packing density of the alkanethiols on copper surface increased with the alkyl chain lengths. XRD patterns gave us useful information about superlattice formations. Finally, $Cu_2O$ was formed when the molar ratio of dodecanethiol to copper is less than unity and copper nanoparticles formed more compact 3D SAMs when the molar ratio of dodecanethiol to copper was 1.25.

• Korean Journal of Crystallography
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• v.16 no.2
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• pp.107-127
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• 2005

Five Cu(II) compounds were obtained from different copper salts with btp ligands, and their structures were determined by X-ray crystallography. The structure of coordination polymer 2 contains btp-bridged tetranuclear Cu(II) units weakly connected by nitrate ions, and the structure of a discrete Cu(II) molecule 1 contains acetates and btp ligands. With perchlorate anions, two btp ligands bridge Cu(II) ions to form a double zigzag chain 3, while a single zigzag chain 4 is created with sulfate anions. The reaction of $Cu(NO_{3})_{2}$ containing $NH_{4}PF_{6}$ with btp ligands also produced a polymeric compound 5 containing $Cu(H_{2}O)_{2}^{2+}$ and $Cu(NO_{3})_{2}$ units alternatively bridged by btp ligands with H-bonds between copper bonded water and nitrate oxygen atoms. Five Zn(II) compounds were obtained from different zinc salts with btp ligands, and the structures of polymeric compounds (6, 7 and 8) and monomeric compounds (9 and 10) were determined by X-ray crystallography. With nitrate, chloride and bromide anions, btp ligands bridge Zn(II) ions to form polymeric compounds (6, 7 and 8), but btp ligands coordinate to a Zn(II) ion to form monomeric complexes (9 and 10) with $PF_{6}^{-}$ and perchlorate anions. Four silver salts and btp ligands produced two kinds of structures, dinuclear 20-membered rings and one-dimensional zigzag chain depending on different anions. For $ClO_{4}^{-}$ and OTf anions, weak interactions between Ag(I) and anions make dinuclear 20-membered rings construct polymeric compounds (11 and 13). For $PF_{6}^{-}$ anion, there are also weak interactions between Ag(I) and $F(PF_{6}^{-})(12)$, but they do not construct a polymeric compound. For $O_{2}CCF_{3}^{-}$ anion, btp ligands bridge Ag(I) atoms to make one-dimensional zigzag chain (14), and there are also interactions between Ag(I) and anions.

• Carbon letters
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• v.5 no.4
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• pp.180-185
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• 2004

Thermolysis of $Cu(NO_3)_2{\cdot}3H_2O$ impregnated activated carbon fiber (ACF) was studied by means of XRD analysis to obtain Cu-impregnated ACF. $Cu(NO_3)_2{\cdot}3H_2O$ was converted into $Cu_2O$ around $230^{\circ}C$. The $Cu_2O$ was reduced to Cu at $400^{\circ}C$, resulting in ACF-C(Cu). Some Cu particles have a tendency to aggregate through the heat treatment, resulting in the ununiform distribution in ACF. Catalytic decomposition of NO gas has been performed by Cu-impregnated ACF in a column reactor at $400^{\circ}C$. Initial NO concentration was 1300 ppm diluted in helium gas. NO gas was effectively decomposed by 5~10 wt% Cu-impregnated ACF at $400^{\circ}C$. The concentration of NO was maintained less than 200 ppm for 6 hours in this system. The ACF-C(Cu) deoxidized NO to $N_2$ and was reduced to ACF-$C(Cu_2O)$ in the initial stage. The ACF-$C(Cu_2O)$ also deoxidized NO to $N_2$ and reduced to ACF-C(CuO). This ACF-C(CuO) was converted again into ACF-C(Cu) by heating. There was no consumption of ACF in mass during thermolysis and catalytic decomposition of NO to $N_2$ by copper. The catalytic decomposition was accelerated with increase of the reaction temperature.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1687-1691
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• 2014

This study reports on the synthesis of carbon nanofibers via chemical vapor deposition using Co and Cu as catalysts. In order to investigate the suitability of their catalytic activity for the growth of nanofibers, we prepared catalysts for the synthesis of carbon nanofibers with Cobalt nitrate and Copper nitrate, and found the optimum concentration of each respective catalyst. Then we made them react with Aluminum nitrate and Ammonium Molybdate to form precipitates. The precipitates were dried at a temperature of $110^{\circ}C$ in order to be prepared into catalyst powder. The catalyst was sparsely and thinly spread on a quartz tube boat to grow carbon nanofibers via thermal chemical vapor deposition. The characteristics of the synthesized carbon nanofibers were analyzed through SEM, EDS, XRD, Raman, XPS, and TG/DTA, and the specific surface area was measured via BET. Consequently, the characteristics of the synthesized carbon nanofibers were greatly influenced by the concentration ratio of metal catalysts. In particular, uniform carbon nanofibers of 27 nm in diameter grew when the concentration ratio of Co and Cu was 6:4 at $700^{\circ}C$ of calcination temperature; carbon nanofibers synthesized under such conditions showed the best crystallizability, compared to carbon nanofibers synthesized with metal catalysts under different concentration ratios, and revealed 1.26 high amorphicity as well as $292m^2g^{-1}$ high specific surface area.

• Restorative Dentistry and Endodontics
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• v.10 no.1
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• pp.63-70
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• 1984

It was the purpose of this study to determine the galvanic current between a gold alloy inlay and four types of amalgam using the circuit through pulp chambers when the freshly extracted teeth with those restorations were brought into contact in a physiologic saline solution, and to investigate the effectiveness of cavity varnish or ammonated silver-nitrate on the surface of amalgam restoration in reducing galvanic current. The current was measured with current-to-voltage converter and recored on a physiograph 6630-257. The following results were obtained. 1. Generally, galvanic current decreased as the time elapsed. 2. Galvainc current decreased significantly in the first day and after then minimal change was observed until 30th day. 3. Initial galvanic current was 29.6 ${\mu}A$ in the cut amalgam and 24.5 ${\mu}A$ in Dispersalloy amalgam and after then the current was significantly decreased. 4. Initial galvanic current was 12.6 ${\mu}A$ in spherical amalgam (low copper amalgam) and 13.8 ${\mu}A$ in Tytin amalgam and the amount of change was lower in sperical amalgam and Tytin amalgam than that in lathe cut amalgam and Dispersalloy amalgam. 5. Painting ammoniated silver-nitrate or Copalite on the surface of amalgam resotration decreased initial galvanic current and ammoniated silver-nitrate is more effective in decreasing galvanic current than Copalite. 6. Galvanic current by contact between amalgam restoration and gold restoration increased abruptly and dropped rapidly becoming almost.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.261-268
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• 1996

Various $Cu/SiO_2$ catalysts with copper concentration ranging from 0 to 50wt% were prepared by kneading method for the steam reforming of methanol. These catalysts were calcined at temperatures in the range of $400^{\circ}C{\sim}900^{\circ}C$ and then reduced in a $H_2$ atmosphere in the range of $150^{\circ}C{\sim}350^{\circ}C$. Steam reforming of methanol was carried out at atmospheric pressure over a temperature range of $200^{\circ}C{\sim}400^{\circ}C$, steam/methanol molar ratio of 0.4~1.6 and W/F of 3~25 g.-cat.hr./mol. Characterization of the catalysts was studied using IR, BET and XRD. Using copper nitrate as a precursor for catalysts, pH in the preparation of catalysts had a great effect on the catalytic activity, but pH in the preparation of catalysts, calcination temperature, and reducing temperature in $H_2$ atmosphere had no effect on the product distribution. Optimum copper concentration, calcination temperature and reducing temperature were 40wt%, $700^{\circ}C$ and $300^{\circ}C$, respective)y. Reaction temperature for maximum $H_2$ production was $275^{\circ}C$, and the formation of methane which lowered quantity and quality of $H_2$ would be inhibited below $275^{\circ}C$. $Cu^{\circ}-Cu_2O$ might be active species in $Cu/SiO_2$ catalyst.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1009-1012
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• 2003

A novel powder processing technique for the preparation of copper activated zinc sulfide (ZnS:Cu,Al) phosphor by combustion process has been proposed. Exothermic reaction between dissolved copper nitrate and carbohydrazide give small-sized particles in presence of alkali metal halides at lower temperature than the traditional method of preparation. This new route takes less than five minutes and requires much less energy. The optical and luminescence characteristics of ZnS:Cu,Al phosphor thus prepared were found to be enhanced significantly. Carbohydrazide acted as fuel at $500^{\circ}C$ with rapid heating and then the phosphors obtained were heated at $900^{\circ}C$ in an inert atmosphere for 3hrs to get better luminescent properties.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.759-761
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• 2002

A new method for the preparation of copper activated zinc sulfide phosphors by combustion method has been proposed. Copper nitrate was decomposed with an organic fuel to give fine sized particles in presence of alkali metal halides at low temperature than the conventional synthesis. Organic compound also acted as fuel at 500 $^{\circ}C$ with rapid heating. The phosphors thus obtained were then heated at 900 $^{\circ}C$ in an inert atmosphere for 2-5 hrs to get better luminescent properties.

• Bulletin of the Korean Chemical Society
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• v.28 no.6
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• pp.1057-1059
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• 2007