• 한국환경과학회지
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• 제8권1호
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• pp.51-59
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• 1999

Chemical composition of atmospheric aerosols was measured at 4 sites in Pusan. All the samples were collected with a high volume air sampler from January to October 1996, to analyze major ions and heavy metals. Dominant ions of aerosols were S $O_4$$^{2-}$ in anion and N $a^{+}$ in cation. Sulfate, nitrate and ammonium ions in aerosols showed high enrichment factor to soil and seawater composition. The concentrations of heavy metals in aerosols was lowest at the site PI near the coast. The lowest concentrations of major ions and heavy metals mainly appeared in August, probably due to scavenging by frequent rains. Especially, the concentrations of total suspended particulate matter(TSP) and heavy metals in aerosols showed good correlations in Pusan. Based on crustal Al, enrichment factors for some metals(Zn, Cu, Pb, Cd) in aerosols were significantly greater than unity, and the order was Cd ＞ Pb ＞ Zn ＞ Cu. This evidence suggests that Cd and Pb are derived predominantly from non-crustal sources.s.

• 한국광물학회지
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• 제16권3호
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• pp.201-213
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• 2003

각종 산업폐수에서 심각한 환경문제를 야기시킬 수 있는 중금속(Ag, Pb, Cr, Cu, Zn, Mn) 이온들에 대한 국내산 주요 제올라이트의 흡착 성향 및 능력을 광물 조성 및 특성 분석과 일련의 흡착실험을 통해서 광석 단위로 평가해 보았다. 국내산 제올라이트 광석의 중금속 흡착 반응은 기본적으로는 양이온 교환방식에 의존되지만, 높은 CEC 값이 반드시 보다 많은 중금속 흡착능력을 의미하는 것은 아닌 것으로 나타난다. 제올라이트 광석의 중금속 흡착성향은 광종별로 다소 차이를 보이지만, 일반적으로 흡착선호도에 있어서 $Ag\geq$Pb>Cr, $Cu\geq$Zn>Mn와 같은 흡착 서열을 이루는 것으로 밝혀졌다. 휼란다이트는 Cr을 보다 더 선호하는 성향을 보이는 반면에, 클리놉틸로라이트는 Cu를 더 선호하는 경향을 나타낸다. 일반적으로 제올라이트의 광종에 관계없이 Ag와 Pb는 상대적으로 월등한 흡착선호도를 나타낸다. 특히 Ag는 Na에 의한 재용출 과정에서 전혀 유리되지 않을 정도로 제올라이트에 대한 높은 흡착성향을 보인다. 제올라이트 광석의 중금속 흡착능력은 광종별로 현격한 차이를 보인다: 페리어라이트>클리놉틸로라이트>휼란다이트. 이에 비해서 모오데나이트는 CEC 성향으로 보아 클리놉틸로라이트와 비슷한 수준인 것으로 해석된다. 제올라이트의 암모늄 이온에 대한 CEC 값과 중금속 이온 흡착능력은 엄밀히 잘 부합되지 않는 것으로 나타난다. 또한 제올라이트 광석들의 중금속 흡착능력은 대개 제올라이트의 함량, 즉 광석의 품위에 의존되는 경향을 보이지만, 광석에 따라 그 일반적 추이에서 크게 벗어난 흡착 양상을 보이기도 한다. 이는 제올라이트의 선택적 흡착특성, 중합단층의 존재와 같은 구조적 결함이나 천연상 교환성 양이온의 조성(특히 흡착선호도가 높은 K의 함유도)에 의한 효과로 추정된다. 국내산 제올라이트를 중금속 흡착제거용으로 응용하는 데에는 부존자원의 활용성, 경제성 및 성능을 고려하여 클리놉틸로라이트 계열의 광석을 사용하는 것이 합리적일 것으로 판단된다.

• 한국토양비료학회지
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• 제47권3호
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• pp.172-178
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• 2014

Soil properties and heavy metal (HM) concentrations in the field soils where balloon flowers (Platycodon grandiflorum, BF) were cultivated, were investigated together with HM (Cd, Cu, Pb, and Zn) accumulation by the BF roots. Basically, in most soils examined (51-97% among 65 samples), the chemical properties including soil pH, organic matter, available-P, and exchangeable cation contents appeared to be lower than the optimal ranges for balloon flower cultivation. There were no samples exceeding the standard limits for HM in soils. Instead, the total HM concentration levels in soils appeared to be maintained at around background levels for general soil in Korea. This implied that elevated HM accumulation in the soils caused by any possible input sources was unlikely. Even though the BF cultivated soils were not contaminated by HM, it was appeared that substantial amount of Cd was accumulated in BF roots with 1.5% and 35% roots samples exceeding the standard limits legislated for BF root ($0.81mg\;kg^{-1}DW$) and herbal plants ($0.3mg\;kg^{-1}DW$), respectively. This implied that the soil HM standard limits based on the total concentration does not reflect well the metal accumulation by plants and also it is likely that the Cd standard limits for BF and herbal plants is too restrict.

• Membrane and Water Treatment
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• 제11권3호
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• pp.179-187
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• 2020

Electrodialysis has been applied for treatment of industrial wastewater including metal electroplating. The wastewater from metal plating industries contains high concentrations of inorganics such as copper, nickel, and sodium. The ions in the feed were separated due to the electrical forces in the electrodialysis. The concentrate compartment is exposed to the elevated concentrations of the ions and yielded inorganic precipitations on the cation exchange membranes. The presence of organic matter in the metal plating wastewater affects complex interfacial reactions, which determines characteristics of inorganic scale fouling. The wastewater from a metal plating industry in practice was collected and the inorganic and organic compositions of the wastewater were analyzed. The performance of electrodialysis of the raw wastewater was evaluated and the effects of adjusting pH of the raw water were also measured. The integrated processes with neutralization and electrodialysis showed great removal of heavy metals sufficient to discharge to aquatic ecosystem. The organic matter in the raw water was also reduced by the neutralization, which might enhance removal performance and alleviate organic fouling in the integrated system.

• 환경위생공학
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• 제15권3호
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• pp.44-49
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• 2000

The purpose of this research is to evaluate the adsorption capacity of casts for heavy metals. The casts were excreted by earthworm, Lumbricus rubellus, after having eaten the paper sludge. Various batch experiments on adsorption were performed to compare cast and activated carbon. The pH increase in solution due to extractives from cast was 1.3 and the cation exchange capacity which implies adsorption capacity for solubles is greater on activated carbon than on cast. According to the results of batch experiment, the removal rates of Pb, Cu, Cr, Zn using the activated carbon and casts as adsorbent were 98%, 93%, 94%, 89%, 82% and 95%, 90%, 88%,80%, 66%, respectivity, and this removal were achived less than 90 minutes. It can be said that casts is so good adsorbent as activated carbon is, although adsorption carbon was found to be some large than those of casts through Freundlich isotherm applied for adsorption of soluble. As a result on the experiment of isothermic adsorption from the mixed component solution in the batch, the order of preferable elements in heavy metal adsorption was found to be Pb＞Cd＞Cu＞Cr＞Zn on activated carbon, respectively.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.435-442
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• 2000

Batch test and column test were performed to develop the design factors for permeable reactive barriers(PRBs) against ammonium and heavy metals, Clinoptilolite, a kind of natural zeolites having excellent cation exchange capacity(CEC), was choosen for the reacting materials through the ion-exchange mechanism. In the batch test, the reactivity of clinoptilolite for ammonium, lead, and copper was examined varying the initial concentration of contaminants(ammonium: 20, 40, 80 ppm, heavy metals: 10, 20, 40 ppm) and the particle size of clinoptilolites(0-0.15, 0.42-0.85, 1-1.25 mm). The reactivity is increasing as the initial concentration decrease and particle size decrease. In the column test, the permeability and the reactivity of the specimens were examined using flexible-wall permeameter. Specimens were made of clinoptilolite and Jumunjin-sand with 20 : 80 weight ratio varying particle size of clinoptilolite. The maximum permeability(1${\times}$10$\^$-4/-5${\times}$10$\^$-5/cm/s) was achieved in the specimen made of 0.42-0.85 mm clinoptilolite and sand.

• 한국염색가공학회지
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• 제26권1호
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• pp.7-12
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• 2014

Nowdays, fluorescent rhodamine chemosensors have attracted a worldwide interest due to its ability to selectively detect heavy and transition metal cations. Due to the importance in environmental and biological toxic effects, the developments of fluorescent chemosensors have been received considerable attention in recent. Especially, a rhodamine-based chemosensor probes have been proved to be useful by exhibiting the efficient "off-on" fluorescence switching toward selected metal cations. This fluorophore can undergo the transformation from non-fluorescent and colorless spirolactam derivative to fluorescent ring-open form. In this study, a new fluorescent chemosensor was synthesized using rhodamine B through two-step procedures, and its selectivity and related optical property were characterized. Selectivity and sensitivity was found toward $Cu^{2+}$ guest molecules and then related optical properties of rhodamine B based fluorescent chemosensor compound were characterized using discussed. In addition, computational calculation was used to determine the HOMO/LUMO values.

• 대한환경공학회지
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• 제39권2호
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• pp.51-58
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• 2017

본 연구에서는 오염퇴적물의 원위치 피복을 위한 소재의 적용성 평가를 위해 양이온교환용량이 다른 제올라이트의 중금속 흡착특성을 평가하였다. 실험을 위해 양이온교환용량이 높은 제올라이트(HCzeo, 163.74 cmol/kg), 중간 값의 양이온교환용량의 제올라이트(MCzeo, 127.20 cmol/kg), 양이온교환용량이 낮은 제올라이트(LCzeo, 70.62 cmol/kg)를 사용하였다. 비표면적을 측정한 결과 HCzeo ($59.43m^2/g$) > MCzeo ($52.10m^2/g$) > LCzeo ($10.12m^2/g$)순으로 높은 결과를 나타내었다. 광물학적 조성 분석을 위해 XRD 측정결과 LCzeo는 quartz와 albite로 구성되었고 MCzeo와 HCzeo의 구성광물은 quartz, albite와 더불어 clinoptilolite, heulandite, mordenite도 측정되었다. HCzeo, MCzeo, LCzeo를 이용한 Cd, Cu, Ni, Zn의 동역학적 흡착실험 결과 실험 6시간대에 흡착 평형에 도달하였다. 평형흡착실험 결과 Cd과 Zn의 흡착은 제올라이트의 양이온교환용량에 따라 증가하였지만 Cu와 Ni의 흡착은 양이온교환용량에 따라 증가하는 경향을 보이지 않았다. 이에 따라 오염퇴적물의 원위치 피복적용에 있어 Cd과 Zn으로 오염된 지역은 양이온교환용량이 높은 제올라이트의 피복적용이 효과적이지만 Cu와 Ni로 오염된 지역의 경우 가격이 저렴한 양이온교환용량이 낮은 제올라이트를 적용하여도 무방할 것으로 판단된다.

• International Journal of Control, Automation, and Systems
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• 제4권6호
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• pp.748-755
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• 2006

In this paper, a trade-off design and fabrication of IPMC(Ionic Polymer Metal Composites) as an actuator for a flapping device have been described. Experiments for the internal solvent loss of IPMCs have been conducted for various combinations of cation and solvent in order to find out the best combination of cation and solvent for minimal solvent loss and higher actuation force. From the experiments, it was found that IPMCs with heavy water as their solvent could operate longer. Relations between length/thickness and tip force of IPMCs were also quantitatively identified for the actuator design from the tip force measurement of 200, 400, 640, and $800{\mu}m$ thick IPMCs. All IPMCs thicker than $200{\mu}m$ were processed by casting $Nafion^{TM}$ solution. The shorter and thicker IPMCs tended to generate higher actuation force but lower actuation displacement. To improve surface conductivity and to minimize solvent evaporation due to electrically heated electrodes, gold was sputtered on both surfaces of the cast IPMCs by the Physical Vapor Deposition(PVD) process. For amplification of a short IPMC's small actuation displacement to a large flapping motion, a rack-and-pinion type hinge was used in the flapping device. An insect wing was attached to the IPMC flapping mechanism for its flapping test. In this test, the wing flapping device using the $800{\mu}m$ thick IPMC. could create around $10^{\circ}{\sim}85^{\circ}$ flapping angles and $0.5{\sim}15Hz$ flapping frequencies by applying $3{\sim|}4V$.

• 대한화학회지
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• 제38권2호
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• pp.122-128
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• 1994

거대고리 리간드는 금속이온과 선택적으로 결합하는데, 이를 이용하여 에멀젼 액체막을 통한 금속이온의 이동에 관하여 연구를 수행하였다. 금속이온은 유기층에 있는 운반체에 의하여 source phase에서 recevinng phase으로 이동한다. 운반체로는 거대고리 리간드인 $DBN_3O_3$를 사용하였다. 여기에서 에멀젼 액체막을 통한 금속이온의 이동에 관한 요인과 어떤 금속이온의 선택적 분리에 관하여 검토하였다. 금속이온과 거대고리 리간드 그리고 금속이온과 recevinng phase내에 있는 음이온에 대한 안정도 상수를 금속이온의 선택적 이동에 대한 척도로 조사하였다. 납이온이 혼합 용액에서 다른 금속이온보다 높은 이동속도를 나타내었다. Recevinng phases내의 음이온이 금속이온의 이동에 중요한 역할을 한다.Recevinng phases내에 있는 $NO_3^-$을 $S_2O_3^{2-}$대치하면 이동량이 증가함을 보였는데 이는 $Pb^{2-}-S_2O_3^{2-}$상호작용이 $Pb^{2+}-NO_3^-$상호작용보다 크기 때문이다.