• 자원리싸이클링
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• 제20권6호
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• pp.56-62
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• 2011

지르코늄은 우수한 내식성과 낮은 중성자 흡수단면적로 인해 원자로에서 구조재로 사용된다. 수용액의 pH에 따른 지르코늄을 함유한 화학종의 농도분포와 용해도의 변화를 구했다. 염산과 질산용액에서 지르코늄이온의 착물형성반응을 고려하여 무기산의 농도에 따른 농도분포를 해석하였다. 질산용액에서 Cyanex272에 의한 지르코늄 추출에 관한 문헌자료를 이용하여 지르코늄과 질산이온간의 Bromley매개변수를 구했다. 이와 같이 구한 매개변수값은 등온추출곡선의 계산이나 하프늄과의 분리인자 예측에 활용될 수 있다.

• Bulletin of the Korean Chemical Society
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• 제23권4호
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• pp.575-579
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• 2002

Two-dimensionally cross-linked ultrathin films of poly(maleic acid-alt-methyl vinyl ether) (MA-MVE) and poly(allylamine) (PAA) were produced by using sodium dioctadecyl sulfate (2C18S) as the monolayer template for Langmuir-Blodgett (LB) depositio n. The template molecules were subsequently removed by thermal treatment followed by extraction. The polyion-complexed monolayers of three components, i.e., template 2C18S, co-spread PAA, and subphase MA-MVE, were formed at the air-water interface. Their monolayer properties were studied by the surface pressure-area isotherm. The monolayers were transferred on solid substrates as Y type. The polyion-complexed LB films and the resulting network films were characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). The cross-linking to form a polymer network was achieved by amide or imide formation through heat treatment under a vacuum. SEM observation of the film on a porous fluorocarbon membrane filter (pore diameter 0.1 ㎛) showed covering of the pores by four layers in the polyion complex state. Extraction by chloroform followed by heat treatment produced hole defects in the film.

• Bulletin of the Korean Chemical Society
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• 제16권6호
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• pp.493-498
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• 1995

Ultrathin networks of itaconic acid copolymers and poly(allylamine) were produced by a Langmuir-Blodgett (LB) technique employing a double-chain amine as a monolayer template which was subsequently removed by extraction after thermal crosslinking. Itaconic acid copolymers used were copoly (itaconic acid-ethyl vinyl ether) and copoly (itaconic acid-n-butyl vinyl ether). The polyion-complexed monolayers of three components consisting of template amine, itaconic acid copolymer and poly (allylamine) were formed at the air-water interface. The Langmuir film properties have been studied by the surface pressure-area isotherm and fluorescence microscopy. The monolayers were transferred on solid substrates and were characterized by FT-IR spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy (SEM). Two-dimensional polymer networks were formed through imide or amide linkages by heat treatment under vacuum. The heat-treated films were extracted with chloroform after immersion in aq. sodium chloride to remove the template amines. SEM observation of a LB film on a porous fluorocarbon membrane filter with pore diameter of 0.1 μm showed covering of the pores by six layers in the polyion complex state.

• 한국구조물진단유지관리공학회 논문집
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• 제12권5호
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• pp.133-142
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• 2008

본 연구에서는 보통포틀랜드시멘트(OPC: ordinary Portland cement), 플라이애쉬(PFA: pulverised fly ash), 고로슬래그미분말(GGBFS: ground granulated blast furnace slag), 실리카퓸(SF: Silica fume)등의 각종 결합재를 적용한 시멘트 페이스트의 염소이온 고정화능력에 관하여 연구하였다. 각각의 사용 시멘트 페이스트는 40%의 물/결합재로 PFA, GGBFS 및 SF 혼화제의 각기 다른 치환률을 갖도록 하였으며 미리 혼합수내에 결합재 중량당 0.1~0.3%의 염소이온을 배합수내에 혼입 포함시켜 배합되어 제조되었다. 염소이온의 측정은 7일간 양생 후 수분 추출 방법을 이용하여 측정하였다. 실험을 통해 염소이온 고정화 능력이 결합재 종류 및 치환률에 의존하고 있음을 확인하였고, 총 염소이온량의 증가는 염소이온 고정화능력을 제한하여 결론적으로 염소이온 고정화를 감소시키고 있음을 보였다. 본 연구에서 최대 30%의 치환율을 가진 PFA와 60%의 치환률을 가진 GGBFS의 경우는 OPC보다 염소이온고정화 능력이 작았으며, SF의 치환률의 증가는 고정화를 감소시키고 있음을 확인하였으며, 이는 포졸란계 재료의 잠재 수화반응 혹은 공극수의 pH 저하등의 이유로 판단된다. 재령 7일에서의 염소이온의 고정화능력은 염해부식에 대한 저항성으로 나타내어지며, 염분을 혼입한 경우의 고정화능력의 순서는 30%PFA > 10%SF > 60%GGBFS > OPC로 나타났다. 더욱이 염소이온의 고정화 거동은 Langmuir isotherm 및 Freundlich isotherm으로 잘 표현될 수 있음을 보였다.

• 한국의류산업학회지
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• 제16권3호
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• pp.476-484
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• 2014

The purpose of this study was to investigate the dyeing properties and anti-microbial ability of silk and wool fabrics dyed with Terminalia chebula Retzius(TCR) extract using two extraction solvent, hot water and methanol. Dyeing properties of fabrics were studied by investigating the characteristics of colorant, changes in dye uptake under different dyeing conditions, and by investigating color change when mordants were applied. Also, color fastness, and antimicrobial activity of dyed fabrics were estimated. Regardless of extraction solvent type, colorant showed maximum absorption wavelength at 280 nm and 578 nm, which implied that tannin was the major pigment component of TCR. Also, through FT-IR spectrum result, it was confirmed that tannin of TCR methanol extract was hydrolysable tannin. But for the hot water extract, it was only assumed that its tannin was condenced tannin. Fabric dyed with hot water solvent extract showed higher dye uptake than fabric dyed with methanol solvent extract, dye uptake increasing by higher concentration of the dye, longer dyeing time and higher dyeing temperature. And the absorption curve between TCR extract and protein fiber was shaped in the form of Langmuir adsorption isotherm. Fabric dyed without mordant was yellow in color, and when dyed with mordant, fabric showed various colors depending on mordant types except Sn. Color fastness to washing was generally fine and color fastness to light was moderate. But color fastness to rubbing and dry cleaning was outstanding. Lastly, dyed fabrics showed very good antimicrobial activity of 99.9% against Staphylococcus aureus and Kiebsiella pneumoniae.

• 한국지하수토양환경학회지:지하수토양환경
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• 제12권3호
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• pp.23-28
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• 2007

동전기적 처리에 의한 무기 오염 물질의 이동 및 제거율을 조사하기 위해 일련의 흡착/탈착 실험 및 동전기 정화 실험을 실시하였다. 동전기적 효과로 인해 발생된 양극 부근에서의 탈착 현상 및 음극 부근에서의 침전 현상을 중금속으로 오염된 점토 시료의 흡착 및 탈착 특성과 비교하여 분석하였다. 제거 효율은 300 V/m의 전압구배로 약 4시간의 동전기적 처리 결과 80% 정도의 높은 제거 효율을 확인할 수 있었다.

• 산업기술연구
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• 제20권A호
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• pp.57-62
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• 2000

This experiment was done to investigate the leaching and adsorption properties of heavy metals on porphyry. The comparison with respect to the leachability of heavy metals from porphyry between the Korea Standard Leaching Test (KSLT) and the Toxicity Characteristic Leaching Procedure (TCLP) was carried out. The fractional composition of leachate and the total concentration of heavy metal of porphyry were studied through Sequential Extraction Procedure (SEP) and EPA Method 3050. Adsorption experiment of porphyry has pointed out that the optimum dosage of porphyry for 50ppm Pb was over 10g/L, the effective particle size for absorption was below 200 mesh and the optimum pH was about 7. From the Freundlich' adsorption equation, 1/n was 1.0722, and k was 0.0041. After adsorption, the fractional composition of Pb was changed. The exchangeable, carbonate, reducible fractions were increased, and the organic fraction was not changed, and the residual fraction was decreased.

• 한국환경과학회지
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• 제23권9호
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• pp.1583-1591
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• 2014

PVA-D2EHPA/TOPO beads containing two extractants, di-(2-ethylhexyl) phosphoric acid (D2EHPA) and trioctylphoshine oxide (TOPO) were prepared for the removal of copper ions from aqueous solution. The prepared PVA-D2EHPA/TOPO beads were characterized by SEM and FT-IR. The removal characteristics of copper ions by PVA-D2EHPA/TOPO beads was investigated using batch and continuous systems. In batch experiments, the maximum removal capacity calculated from Langmuir isotherm model was 18.6 mg/g and the optimal pH was in the range of 4.5~6. The continuous experiments showed that the removal capacity of copper ions increased with increasing inlet copper ion concentrations and bed heights, but decreased with increasing inlet flow rates.

• 한국환경과학회지
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• 제23권6호
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• pp.1157-1163
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• 2014

The solid phase extractant (PVC-D2EHPA bead) was prepared by immobilizing di-2-ethylhexyl-phosphoric acid (D2EHPA) with polyvinyl chloride (PVC). The prepared PVC-D2EHPA beads were characterized by using fourier transform infrared spectrometer (FTIR) and scanning electron microscopy (SEM). The removal experiments of Cu(II) by PVC-D2EHPA beads conducted batchwise. The removal kinetics of Cu(II) was found to follow the pseudo-second-order model. The equilibrium data fitted well with Langmuir isotherm model and the maximum removal capacity was 2.6 mg/g at $20^{\circ}C$. The optimum pH region was in the range of 3.5 to 6. and the standard free energy (${\Delta}G^{\circ}$) was between -4.67~-4.98 kJ/mol, indicating the spontaneous nature of Cu(II) removal by PVC-D2EHPA beads.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2006년도 총회 및 춘계학술발표회
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• pp.407-410
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• 2006

Studies were performed on evaluating the applicability of activated carbon bugs on dye tracer tests as tracer detectors by using its adsorption isotherm of the grained activated carbon. We preliminary conducted several standard adsorption and extraction tests and obtained the relationship between standard dye solution and detected concentrations from activated carbon samples in dry and wet conditions. the slopes of the regression line were 0.71 for wet condition and 0.74 for dried one. Field dye tracer tests were performed in a karst area, where several faults occur along a stream and pass the test area. We sampled water samples and activated carbon samples at three points in Hwangji Pond, where groundwater outflows from the karst conduit. According to the results of breakthrough curve analysis, the regional flow along the conduit, which is assumed to cause a karst conduit, was estimated as 0.18 m/day. The relationship between the concentrations of water sample and extracted activated carbon bugs shows the similar slopes with those from standard solution tests. This suggests that activated carbon could be useful as a dye tracer detector because the extraced concentration can be quantified.