• Journal of the Korean Chemical Society
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• v.62 no.2
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• pp.79-86
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• 2018

This study reported the adsorption of Cu(II) ions onto activated carbon prepared from Myristica Fragrans shell (MFS AC) over independent variables of contact time, activating chemical (NaOH) concentration, initial adsorbate concentration, initial pH of adsorbate solution and adsorption temperature. The MFS AC structure, morphology and total surface area were characterized by FTIR, SEM and BET techniques, respectively. The Cu(II) ions adsorption on the MFS AC (activated using 0.5 M NaOH) fitted best to Freundlich adsorption isotherm (FAI), and the FAI constant obtained was 0.845 L/g at $30^{\circ}C$ and pH 4.5. It followed the pseudo first order of adsorption kinetic (PFOAK) model, and the PFOAK based adsorption capacity was 107.65 mg/g. Thermodynamic study confirmed the Cu(II) ions adsorption should be exothermic and non-spontaneous process, physical adsorption should be taken place. The total surface area and pore volume based on BET analysis was $99.85m^2/g$ and 0.086 cc/g, respectively.

• Solar Energy
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• v.15 no.1
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• pp.73-84
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• 1995

The present paper is on the utilization of a thermal decomposition reaction $Ca(OH)_2=CaO+H_2O$, for thermal energy storage. One of the important problems in this case is how to heat up and decompose the particle of $Ca(OH)_2$ effectively where the thermal conduction is poor. In this study, the effects of Cu-plates which are placed in the $Ca(OH)_2$ packed bed as heat transfer fins are investigated experimentally. The results show that the Cu-plates are very effective for heat transfer and the thermal decomposition in the $Ca(OH)_2$ packed bed. The amount of time to dehydrate took less than a half than that without fins under the conditions of this study.

• Proceedings of the Korean Vacuum Society Conference
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• 2015.08a
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• pp.178.2-178.2
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• 2015

In and Ga doped ZnO (IGZO) films were deposited on 5 nm thick Cu film buffered Polycarbonate (PC) substrates with RF magnetron sputtering and then the effect of Cu buffer layer on the optical and electrical properties of the films was investigated. While IGZO single layer films show the electrical resistivity of $1.2{\times}10-1{\Omega}cm$, IGZO/Cu bi-layered films show a lower resistivity of $1.6{\times}10-3{\Omega}cm$. Although the optical transmittance of the films in a visible wave length range is deteriorated by Cu buffer layer, IGZO films with 5 nm thick Cu buffer layer show the higher figure of merit of $2.6{\times}10-4{\Omega}-1$ than that of the IGZO single layer films due to the enhanced opto-electrical performance of the IGZO/Cu bi-layered films.

• Knowledge Management Research
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• v.16 no.2
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• pp.193-212
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• 2015

A corporate university (CU) is an educational institution established by an organization whose primary purpose is not education. Traditionally, a CU is considered a training facility to improve organizational performance. However, the proliferation of the CU has engendered its diverse purposes, roles, and forms. This study attempts to identify three types of the existing CUs: (a) a CU to improve organizational performance; (b) a CU to satisfy employees' learning needs; and (c) a CU to develop a competent national workforce. Also, this study suggests a holistic CU model including the three CU types. In order to transform a CU to a multifunctional CU embracing all three types of CU, organizations should (a) provide communication and collaboration channels, (b) present clear organizational goals, (c) establish organizational policies/systems to encourage learning in CUs, and (d) devise an effective approach to evaluate the impact of CUs. Organization' s critical roles in the development of CUs can assist CUs in becoming the core of knowledge management.

• Journal of the Korean Chemical Society
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• v.18 no.3
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• pp.194-201
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• 1974

The tetradentate schiff base ligand, N,N'-bis(salicylaldehyde)-m-phenylenediimine has been prepared from salicylaldehyde and m-phenylenediamine by Duff-reaction. The schiff base ligand has been reacted with Cu(II), Ni(II), Co(II), and Zn(II) to form new complexes; Cu(II)$[C_{20}H_{14}O_2N_2]{\cdot}2H_2O, Ni(II)[C_{20}H_{14}O_2N_2]{\cdot}2H_2O, Co(III)[C_{20}H_{14}O_2N_2]{\cdot}2H_2O and Zn(II)2[C_{20}H_{14}O_2N_2]{\cdot}4H_2O$. It seems to be that the Cu(II), Ni(II) and Co(II) complexes have hexacoordinated configuration with the schiff base and two molecules of water, while Zn(II) complex has tetracoordinated configuration with the schiff base and four molecules of water. The mole ratio of tetradentate schiff base ligand to Cu(II), Ni(II) and Co(II) are 1:1 but to Zn(II) is 1:2. These complexes have been identified by visible spectra, infrared spectra, T.G.A. and elemental analysis.

• Journal of the Korean Chemical Society
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• v.36 no.6
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• pp.796-801
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• 1992

An empirical Lewis basicity, DN, for eight mixed methanol solvents has been measured by the solvatochromic behavior of the [Cu(tmen)(acac)]$CIO_4$. The change of DN in mixed methanol solvents is not correlated with composition of the mixtures and divided into three groups: (1) dipolar aprotic solvents contribute mainly to the solvation of solute (MeOH-DMSO, MeOH-PY, MeOH-DMF), (2) two components of mixture contribute equally to the solvation of solute (MeOH-MeCN, MeOH-dioxane, MeOH-AC) and (3) methanol contributes entirely to the solvation of solute (MeOH-DCE, MeOH-TCE). The relationship between DN and Kamlet-Taft's $B_{KT}$ for mixed methanol solvents was found to agree well. These DN values also were a useful factor to analysis of reactivity for mixed methanol solvents.

• Korean Journal of Agricultural Science
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• v.9 no.2
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• pp.584-590
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• 1982

Copolymerization of the 4-vinylpyridine with vinylacetate and divinylbenzene initiated by azobis-isobutyronitrile was carried out in DMF in presence $BaCl_2$ at $98^{\circ}C$. Ion exchange res in, poly 4-vinylpyridine-vinylsulfonic acid-divinylbenzene was prepared by sulfonation of 4-vinylpyridine-vinylacetatp-divinylbenzene with concentrated sulfuric acid. The compositions of each synthetic resin were identified by means of ir adsorption spectroscopy. Anion and cation capacities of 4-vinylpyridine-vinylsulfonic acid-divinylbenzene ion exchanger were 2.5meq/g and 4.8meq/g, respectively. Adsorption of Cd(II) and Cu(II) ions have showed larger quantity in alkalie media. A study also was made of the influence of alcohol on the distribution coefficient of Cd(II) and Cu(II) ions between the synthetic ion exchanger, and solution containing hydrochloric acid, various alcohols and water. The distribution coefficients of metal ions decrease generally as the number of branches of carbon in the molecule of butyl alcohol increase. (t-BuOH

• Journal of Electrochemical Science and Technology
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• v.9 no.4
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• pp.276-281
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• 2018

High concentration of copper in mezcal, a representative Mexican spirituous alcoholic beverage, is a serious problem due to the damage that it may cause to human health. A cyclic voltammetry and square wave anodic stripping voltammetry study of copper (II) in three commercial mezcal samples based on glassy carbon electrode response was undertaken. The analysis was developed using a simulated matrix solution ($EtOH/H_2O$ (1:1), 0.1 M $LiClO_4$ and AcOH/AcONa 0.05 M/0.008 M), with Cu (II) concentrations in the range 0 - 1 ppm. Direct electrochemical analysis of mezcal samples was complicated by the presence of different organic compounds in the matrix. The analytical signal of Cu (II) in the spirituous was notably improved and the interferences caused by organic compounds were minimized, by diluting the mezcal samples 10% with $EtOH/H_2O$ (1:1) solution. An efficient quantification of Cu (II) was obtained from the calibration curve by the SWASV and using the internal standard method (Cd (II)) in commercial samples (1.2-6.7 ppm); the results were correlated satisfactorily with the values obtained by AAS.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2012.05a
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• pp.317-317
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• 2012

본 연구는 전착법으로 형성된 $Cu_2O$ 박막의 광특성 변화를 고찰한 것이다. 0.3M $CuSO_4$과 4M Lactic acid에 4M NaOH로 전해액의 pH를 조절하여 $Cu_2O$ 박막의 결정성 및 극성을 조절하였다. $Cu_2O$ 박막의 결정성 및 극성에 따른 광특성을 고찰한 결과, 무극성인 (111)면에서 광특성이 우수함을 확인하였다. 하지만, 측정시간의 증가에 따라 표면에 Cu 금속이 형성되어 광전류가 감소함을 확인 할 수 있었다.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.10
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• pp.889-893
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• 2006

Chemical mechanical polishing (CMP) achieves surface planrity through combined mechanical and chemical means. The role of slurry is very important in metal CMP. Slurry used in metal CMP normally consists of oxidizers, complexing agents, corrosion inhibitors and abrasives. This paper investigates the effects of citric acid as a complexing agent for Cu CMP with $H_2O_2$. In order to study chemical effects of citric acid, X-ray photoelectron spectroscopy (XPS) was peformed on Cu sample after etching test. XPS results reveal that CuO, $Cu(OH)_2$ layer decrease but $CU/CU_2O$ layer increase on Cu sample surface. To investigate nanomechanical properties of Cu sample surface, nanoindentation was performed on Cu sample. Results of nanoindentation indicate wear resistance of Cu surface decrease. According to decrease of wear resistance on Cu surface removal rate increases from $285\;{\AA}/min\;to\;8645\;{\AA}/min$ in Cu CMP.