• Journal of the Korean Chemical Society
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• v.36 no.1
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• pp.24-27
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• 1992

Silver sols are aggregated by a Cu or Zn rod. This is maybe due to the reduction of $Ag^+$ ion on the surfaces of silver sols to Ag metal by oxidation-reduction reaction with Cu or Zn metal. Raman spectra of silver sols aggregated by a Cu rod have been studied. The evidence of borate and nitrate ions adsorbed on silver colloid surfaces is found. It is also found that these ions adsorbed on silver colloid surfaces are easily replaced by adsorbated added.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.1
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• pp.83-89
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• 2000

Bentonite has been considered as a liner material to restrict the release of hazardous heavy metals from the landfill. The adsorption of copper onto a domestic bentonite was studied to provide the adsorption isotherm and the effect of solution chemistry and temperature. The copper adsorption was fitted well to a Freundlich isotherm, in which Freundlich constants and correlation coefficient were calculated to be $K_F=1.18$, n=1.65, and $r^2=0.97$, respectively. The distribution coefficients ($K_d$) for the adsorption of copper decreased with increasing initial copper concentration. The $K_d$ increased with increasing the pH of solution, and drastically increased at pH > 5.3 because of precipitation of most copper species. As the ion strength of $Na^+$ in solution increased the $K_d$ decreased, while it increased with increasing the concentration of $SO_4{^{2-}}$ in solution. An increase in the temperature of experimental solution decreased the $K_d$ values.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.319.2-319.2
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• 2016

ZrN 코팅은 TiN과 특성이 유사한 옅은 금색의 질화 박막이나 내식성이 우수하여 의료용, 자동차 부품, 항공부품, 장식용으로 적용되고 있다. 스테인레스계 의료용 기구나 생활기구의 항균성 기능이 부여된 표면처리는 아직 널리 보급되고 있지 않아 장식성과 내부식성이 뛰어난ZrN 박막에 구리를 함유시킴으로서 항균성의 변화를 관찰하고자 하였다. 진공 아크 이온플레이팅 방법으로서 ZrN을 성장시키면서 스퍼터링법에 의하여 Cu를 함유시키는 방법으로 실험을 실시하였다. 기재는 SUS 304를 사용하였고, 공정온도 $400^{\circ}C$에서 질소분압 1-5 Pa, 아크전류 90 A의 조건에서 Cu 스퍼터링 타겟의 전류를 1-7A 까지 변화하여 구리함유 ZrN 박막을 합성하였다. 구리 함류량에 따른 XRD를 통한 결정구조분석과 SEM/EDX를 통한 성분변화분석을 실시하였다. 구리함유 박막에 대해서 시간에 따른 대장균을 성장을 분석하여 기재인 SUS304, ZrN, 구리 함유 ZrN에 대한 대장균 항균성을 조사하였다.

• Resources Recycling
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• v.11 no.6
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• pp.12-17
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• 2002

Solvent extraction experiments have been performed to separate copper from $CuCl_2$-$NiCl_2$-$CoCl_2$$ solutions using Alamine336 and LIX84. The complex formation tendency between metal ions and chloride ion had a great effect on the distribution coefficients of Cu, Co and Ni ions and separation factor of Cu to Co and Ni. In the experimental ranges of chloride ion concentration from 0.5 to 4.0 M, LIX84 was superior to Alamine336 in separating copper from cobalt. When the volume percentage of LIX84 and Alamine336 was varied from 5 to 40%, LIX84 was more effective than Alamine336 in separating Cu from Co and Ni in solutions in which the chloride ion concentration was 1.0 M.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2013.05a
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• pp.205-205
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• 2013

플라즈마 밀도, 전자 온도, 쉬스 전압이 플라즈마 디웨팅으로 나노 분말 어레이를 제작할 때에 끼치는 영향을 연구하였다. 플라즈마 변수를 조절하여 기판에 입사하는 이온 충돌 에너지가 높은 조건에서는 디웨팅 시에 홀이 상대적으로 많이 생성이 되어 균일한 구리 나노 분말이 생성되었고, 반대의 경우에는 디웨팅 시 홀이 적게 생성되어 크고 작은 나노분말이 혼재해 있는 불균일한 구리 나노 분말 어레이가 형성되었다. 따라서 이온 충돌 에너지를 조절하면 구리 나노 분말의 균일도를 조절할 수 있다.

• Journal of the Korean Vacuum Society
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• v.14 no.1
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• pp.17-23
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• 2005

Glow discharge mass spectrometry(GDMS) was used to determine the impurity concentrations of the deposited Cu films and the 6N Cu target. Cu films were deposited on Si (100) substrates at zero substrate bias voltage and a substrate bias voltage of -50 V using a non-mass separated ion beam deposition method. Since do GDMS has a little difficulty to apply to thin films because of the accompanying non-conducting substrate, we have used an aluminum foil to cover the edge of the Cu film in order to make an electrical contact of the Cu film deposited on the non-conducting substrate. As a result, the Cu film deposited at the substrate bias voltage of -50 V showed lower impurity contents than the Cu film deposited without the substrate bias voltage although both the Cu films were contaminated during the deposition. It was found that the concentration change of each impurity in the Cu films by applying the negative substrate bias voltage is related to the difference in their ionization potentials. The purification effect by applying the negative substrate bias voltage might result from the following reasons: 1) Penning ionization and an ionization mechanism proposed in the present study, 2) difference in the kinetic energy of accelerated Cu+ ions toward the substrate with/without the negative substrate bias voltage.

• Journal of the Mineralogical Society of Korea
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• v.17 no.3
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• pp.209-220
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• 2004

Adsorption behavior of Cu onto Hwangto, from Pankok-ri, Kosung-gun, suspension was studied using Cu batch adsorftion experiment and computer program MINTEQA2 and FITEQL 3.2. The sorption of copper was investigated as a function of pH, copper concentration and $NaNO_3$ background concentration (0.01 and 0.1 M). The concentration of copper was analyzed using ICP-AES. The sorption of copper onto Hwangto suspension increased with increasing pH and copper concentration. The adsorption percentage of copper drastically increased from pH 5.5 to 6.5, and reached nearly 100% at pH 7.5. Because the amount of copper solution and the ionic strength of background electrolyte may not affect the sorption of copper onto Hwangto, the copper ion may be combined at the surface of Hwangto as an inner-sphere complex. Using the MINTEQA2 program, the speciation of copper was calculated as a function of pH and copper concentration. The concentration of $Cu^{2+}$ decreased and that of $Cu(OH)_2$ increased with increasing pH. The uptake of copper in the Hwangto suspension was simulated by FITEQL3.2 program using two sites-three pKas model, which is composed of silicate reaction site and Fe oxide reaction site. The copper absorption reaction constants were calculated in the case of 2～6 mL of copper solution. The Fe oxide reaction site rapidly adsorbs copper ion between pH 4.5～6.5. Silicate reaction site adsorbs little copper ion at low copper concentration but much at high copper concentration. The removal amount of copper by precipitation was negligible in comparison with that of adsorption. The Fe oxide reaction site may has higher adsorption affinity of copper ion than silicate reaction site.

• Resources Recycling
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• v.22 no.6
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• pp.48-54
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• 2013

The methods to separate and remove copper in the mixed solution ((399 ppm Cu, 208 ppm Fe, 15.3 g/L Ni, 2.1 g/L Co) with nickel, cobalt and iron were investigated. With hydroxide precipitation method, copper and iron ions were completely precipitated and removed from the solution at pH 7 while some nickel and cobalt also were precipitated. 99.75% copper could be precipitated and removed as copper sulfide from the solution with adding $Na_2S$ (1.25 w/v concentration) of 2 times equivalent of Cu at pH 1. Copper was selectively absorbed on TP 207 ion exchange resin at equilibrium pH 2.0 and could be eluted from copper-loaded resin using 5% $H_2SO_4$.

• Korean Journal of Optics and Photonics
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• v.8 no.4
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• pp.291-296
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• 1997

The slotted type of hollow copper cathode was constructed and tested for its geometric stability and usability for laser operation at 780nm. The peak output power of copper ion laser emission was measured for different operating conditions. The IR-laser power was dependent on the parameters of the geometry of the hollow cathodes, discharge current and gas fillings. The peak power decreased with increasing neon pressure over 60%. One reason for this decrease in output power may be conjectured as hier due to the decreasing population of the upper laser level. The copper ion laser transition at 780 nm populated at the 5p level. The hollow cathode copper ion laser is operated in He and Ne mixture by electric discharge excitation and could be operated for more than 100 hours with only a 35% drop in the output power(2.8mW cw for 9.6cm active length).

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.4
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• pp.438-445
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• 2017

Tanzania has abundant copper deposits, but copper-metal extraction remains low there, owing to the lack of suitable copper recovery processes and insufficient funds for developing mining technologies. Accordingly, leaching and solvent extraction methods for the extraction of copper from copper ore were studied with a particular emphasis on developing a simple processing method for small-scale copper mining. Chrysocolla ore was used as the copper-bearing mineral and sulfuric acid was used as the leaching reagent. A maximum copper recovery of 95.1% was obtained when the particles in the sample were smaller than $53{\mu}m$, the concentration of 98%(w/w) sulfuric acid in the leaching solution was 5.0 g/L and the stirring rate was between 60 and 80 rpm. The highest selectivity of $Cu^2+$ in the solvent extraction was obtained using 15% LIX-70 in kerosene. In the pH range from 0.5 to 3.0, the efficiency of $Cu^2+$ extraction increased with increasing pH. However, at pH values higher than 3.0, other metal ions were extracted into the organic phase more readily than $Cu^2+$. The highest solvent extraction rate obtained was 96.5% at pH values of 2.0 and 3.0 using 15% LIX-70.