• Membrane and Water Treatment
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• 제7권1호
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• pp.55-70
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• 2016

Microfiltration/ultrafiltration (MF/UF) Adsorptive polyamide-6 (PA-6) membranes were prepared using wet phase inversion process. The prepared PA-6 membranes are characterized by scanning electron microscopy (SEM), porosity and swelling degree. In this study, the membranes performance has examined by adsorptive removal of copper ions from aqueous solutions in a batch adsorption mode. The $PA-6/H_2O$ membranes display sponge like and highly porous structures, with porosities of 41-73%. Under the conditions examined, the adsorption experiments have showed that the $PA-6/H_2O$ membranes had a good adsorption capacity (up to 120-280 mg/g at the initial copper ion concentration ($C_0$) = 680 mg/L, pH7), fast adsorption rates and short adsorption equilibrium times (less than 1.5-2 hrs) for copper ions. The fast adsorption in this study may be attributed to the high porosities and large pore sizes of the $PA-6/H_2O$ membranes, which have facilitated the transport of copper ions to the adsorption. The results obtained from the study illustrated that the copper ions which have adsorbed on the polyamide membranes can be effectively desorbed in an Ethylene dinitrilotetra acetic acid Di sodium salt ($Na_2$ EDTA) solution from initial concentration (up to 92% desorption efficiency) and the PA-6 membranes can be reused almost without loss of the adsorption capacity for copper ions. The results obtained from the study suggested that the $PA-6/H_2O$ membranes can be effectively applied for the adsorptive removal of copper ions from aqueous solutions.

• Bulletin of the Korean Chemical Society
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• 제29권10호
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• pp.2033-2035
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• 2008

• Bulletin of the Korean Chemical Society
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• 제18권8호
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• pp.886-889
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• 1997

The crystal structure and optical properties of copper nanoparticles, prepared in fused silica by ion-implantation and subsequent heat-treatment, were characterized by X-ray, TEM, linear absorption, and degenerate four-wave mixing (DFWM) technique. The X-ray data show fcc lattice structure of the nanocrystals and their size was measured as 8-20 nanometer by high resolution TEM. Using DFWM, the third-order nonlinear optical coefficient of the Cu-SiO2 thin films was measured as 0.4-1.1×10-8 esu in the surface plasmon resonance absorption region (540-570 nm).

• Bulletin of the Korean Chemical Society
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• 제16권5호
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• pp.406-409
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• 1995

The complex formation from Cu(Ⅱ) ion and 2,2-bis(hydroxymethyl)-2,2',2"-nitrilotriethanol (Bistris) in aqueous solution has been studied potentiometrically and spectrophotometrically. Bistris (L) coordinates to Cu(Ⅱ) as tridentate. The complex CuL2+ undergoes deprotonation in neutral and basic media. The deprotonated complexes involve metal-alcoholate coordinate bond in stable chelate structures.

• Bulletin of the Korean Chemical Society
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• 제33권1호
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• pp.95-99
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• 2012

Two novel copper(II) complexes, [Cu(dmamhp)$(H_2O)_2(SO_4)]_n$ (1) and [Cu(dmamhp)$(NO_3)_2(H_2O)]{\cdot}H_2O$ (2) [dmamhp = 2-dimethylaminomethyl-3-hydroxypyridine] have been synthesized and structurally characterized by single crystal X-ray diffraction analysis. Compound 1 displays a double one-dimensional chains structure, in which each chain is constituted with the distorted octahedral copper(II) complex bridged through bidentate sulfate ligands resulting in a coordination polymer. The bifurcated hydrogen bonds and $\pi-\pi$ interactions play important roles in the formation of the double chains structure. On the other hand, compound 2 adopts a distorted square pyramidal geometry around copper(II) ion and exists as a discrete monomer. There are intermolecular bifurcated hydrogen bonds and $\pi-\pi$ stacking interactions between the monomeric units. The magnetic properties revealed that the paramagnetic behaviors are dominantly manifested and there are no intermolecular magnetic interactions in both compound 1 and 2.

• 한국재료학회지
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• 제31권3호
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• pp.162-171
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• 2021

Dry etching of copper thin films is performed using high density plasma of ethylenediamine (EDA)/hexafluoroisopropanol (HFIP)/Ar gas mixture. The etch rates, etch selectivities and etch profiles of the copper thin films are improved by adding HFIP to EDA/Ar gas. As the EDA/HFIP concentration in EDA/HFIP/Ar increases, the etch rate of copper thin films decreases, whereas the etch profile is improved. In the EDA/HFIP/Ar gas mixture, the optimal ratio of EDA to HFIP is investigated. In addition, the etch parameters including ICP source power, dc-bias voltage, process pressure are varied to examine the etch characteristics. Optical emission spectroscopy results show that among all species, [CH], [CN] and [H] are the main species in the EDA/HFIP/Ar plasma. The X-ray photoelectron spectroscopy results indicate the formation of CuCN compound and C-N-H-containing polymers during the etching process, leading to a good etch profile. Finally, anisotropic etch profiles of the copper thin films patterned with 150 nm scale are obtained in EDA/HFIP/Ar gas mixture.

• 미생물학회지
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• 제37권3호
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• pp.197-203
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• 2001

담수식물의 근계(根界) 부착하는 미생물 군집에서 중금속 제거능이 있는 균주인 Pseudomonas. cepacia KH410 을 분리하여 이 균주의 납과 카드윰, 구리에 대한 생흡착 특성을 조사하였다. 최적 흠착조건은 1.0 g-biomass, pH 4, 그리고 온도는 $40^{\circ}C$일 때이었다. 흡착평형은 120분에서, 1000 mg/1농도에서 이루어 졌다. 흡착용량(K)은 납이 카드뮴에 비해 5.6배, 구리에 비해서는 4.0배 높았으며 흡착강도(1/n)는 납>구리>카드뮴의 순이었다. 흠작강도에 따른 등온식 적용은 납은 Langmuir등온식, 그리고 구리와 카드뮴은 Freundlich 등온식 적용이 오차가 적었다. 건조 균체를 이용한 최대 흡착은 납과 카드뮴, 구리에 대하여 각각 83.2, 42.0, 65.2 mg/g-biomass 이었다. 중금속 회수를 위한 탈착 실험에서는 납은 0.1 M HCl에서 그리고 카드뮴과 구리는 0.1 M $HNO_3$에 의하여 높은 탈착율을 나타내었다. 고정화 균체의 강도를 높이기 위한 전처리는 각각의 세 가지 중금속에 대하여 0.1 M KOH가 가장 효율적이었다. 고정화 균체에 의한 최대 흡착은 납, 카드뮴, 구리가 각각 77.8, 58.5, 71.2 mg/g-biomass 이었으며 경금속 혼재시에도 비교적 안정한 상태를 나타내었으며 중금속 제거효율을 비교한 결과 고정화 균체가 이온교환수지에 의한 제거보다 높았다.

• 대한환경공학회지
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• 제22권1호
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• pp.83-89
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• 2000

벤토나이트는 매립지로부터 중금속이 유출되는 것을 저지시키기 위한 라이너 물질로 고려되고 있다. 본 연구에서는 국산 벤토나이트를 대상으로 구리 흡착실험을 수행하였으며, 평형관계식과 용액화학 및 반응온도가 구리흡착에 미치는 영향을 규명하였다. 구리의 흡착반응은 Freundlich 등온선을 비교적 잘 만족하였으며, 결정된 상수 $K_F=1.18$, n=1.65, 상관계수 $(r^2)=0.97$ 이었다. 구리이온의 분배계수는 주어진 초기용액의 농도범위에서 농도가 증가할수록 감소하였다. 구리이온의 분배계수는 pH가 증가할수록 증가하였으며, pH > 5.3 이상에서는 침전반응으로 인해 그 값이 급격하게 증가하였다. $Na^+$의 이온강도가 증가함에 따라 구리이온의 분배계수 값은 감소하였으며, 반면에 용액 중에 존재하는 $SO_4{^{2-}}$의 농도가 증가할 경우에는 그 값이 증가하였다. 그리고 온도가 증가함에 따라 구리이온의 분배계수는 서서히 감소하였다.

• Environmental Analysis Health and Toxicology
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• 제4권3_4호
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• pp.29-59
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• 1989

For the purpose of electrolytic treatment of wastewater containing various heavy metals, the BPBE Cell of batch and continuous type was considered and experimented. Some results from this study were summarized as follows: 1. When the artificial wastewater containing 500 mg/l of the concentration of various heavy metallic ion was electrolyzed in BPBE Cell of batch type, the removal efficicency was over 95% in cadmiun (II), lead (II), chromium (Ⅵ) and over 85% in copper (II), chromium (III). 2, As granular activated carbon packed in BPBE Cell, coconut shell was superior to lignite and the removal efficiency was the highest when the activated carbon was 4/6 mesh, the voltage was 20V. 3. When the heavy metallic ion in wastewater was electrolyzed in BPBE Cell of continuous type, about 1,000mg of heavy metal per 1kg of coconut sell could be removed. 4. The treatment method of heavy metallic ion in wastewater by BPBE Cell cost less than in the former chemical treatment method and the coconut shell packed in BPBE Cell could be regenerated by chemical method.

• 한국표면공학회지
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• 제47권2호
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• pp.63-67
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• 2014

As the demand for fine-pitch FPCB (Flexible Printed Circuit Board) increases, so do the number of applications of sputtered FCCL (Flexible Copper Clad Laminate). Furthermore, as the width between the circuit patterns decreases, greater defects are observed in the migration phenomenon. In this study we observed changes in ion migration in real circuit-pattern width using sputtered FCCL. We found that as the applied voltage and residue thickness of the NiCr seeds increase, ion migration occurs faster. If the NiCr seed layer thickens due to a high cathode power and long deposition time while being sputtered, the NiCr will form a residue that quickly becomes a factor for incurring ion migration.