• Proceedings of the Korea Air Pollution Research Association Conference
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• 1999.10a
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• pp.96-98
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• 1999

환경시료들은 매트릭스의 조성이 매우 복잡하여 공존하는 성분들이 목적성분의 검출에 영향을 미치므로 분리하는 조작이 필요하다. 환경 중에 존재하는 물질들은 동적인 평형상태를 유지하고 있기 때문에 시료를 채취하여 실험실로 운반하여 보관하는 동안에 분석 대상 물질이 용기에 흡착, 휘발 및 화학 반응의 진행 등으로 인하여 시료의 손실 및 변질을 초래 할 수 있다.(중략)

• Proceedings of KOSOMES biannual meeting
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• 2008.05a
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• pp.117-120
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• 2008

As we can see at the oil spill occident on the coast of Taean, the viscosity of the spilled oil becomes thicker as time goes by. It becomes waste oil with the form of tar. It moves to other areas following a tide. When the temperature of the water goes up, the viscosity becomes lighter and forms oil film. It repeats the process spreading to and polluting extensive areas where the tide reaches. People have used hand nets to collect waste oil of tar at the sea. But it is very difficult for them to collect the tar type waste oil spread on large areas before it reaches to the beach. This paper tried to find a way to collect the tar type waste oil efficiently. It used absorption mat of boom type that uses the attachment characteristics of the tar type waste oil and floating waste recovery device of net type. It tested the possibility of using the devices at the oil spill accident on the beach of Taean. The result showed that net type recovery device was much more efficient in collecting the waste oil in short time than the hand net system of people. It confirmed that the net type recovery device could be used to collect tar type waste oil.

• Journal of the Korean Wood Science and Technology
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• v.44 no.5
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• pp.750-759
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• 2016

The $MnO_2$ electrodeposited on the surface of the carbon nanofiber mats ($MnO_2$-LCNFM) were prepared from electrospun lignin-g-PAN copolymer via heat treatments and subsequent $MnO_2$ electrodeposition method. The resulting $MnO_2$-LCNFM was evaluateed for its potential use in a supercapicitor electrode. The increase of $MnO_2$ electric deposition time was revealed to increase diameter of carbon nanofibers as well as $MnO_2$ content on the surface of carbon nanofiber mats as confirmed by scanning electon microscope (SEM) analysis. The electrochemical properties of $MnO_2$-LCNFM electrodes are evaluated through cyclic voltammetry test. It was shown that $MnO_2$-LCNFM electrode exhibited good electrochemical performance with specific capacitance of $168.0mF{\cdot}cm^{-2}$. The $MnO_2$-LCNFM supercapacitor successfully fabricated using the gel electrolyte ($H_3PO_4$/Polyvinyl alcohol) showed to have the capacitance efficiency of ~90%, and stable behavior during 1,000 charging/discharging cycles.

• Applied Chemistry for Engineering
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• v.30 no.2
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• pp.233-240
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• 2019

Molecular recognition technology has attracted considerable attention for improving the selectivity of a specific molecule by imprinting it on a polymer matrix. In this study, adsorption and release characteristics of chitosan based drug delivery films imprinted with sulindac (SLD) were investigated in terms of the plasticizer, temperature and pH and the results were also interpreted by the related mathematical models. The adsorption characteristics of target molecules on SLD-imprinted polymer films were better explained by the Freundlich and Sips equation than that of the Langmuir equation. The binding site energy distribution function was also useful for understanding the adsorption relationship between target molecules and polymer films. The drug release of SLD-imprinted polymer films followed the Fickian diffusion mechanism, whereas the drug release using artificial skin followed the non-Fickian diffusion behavior.

• Journal of the Korean Wood Science and Technology
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• v.33 no.3 s.131
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• pp.22-29
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• 2005

This research was carried out not only to examine the proper manufacturing condition for white charcoal board in relation to charcoal particle size and final mat moisture content (FMC), but also to maintain the advantageous properties of white charcoal as a well being building material against the sick house problem. Excellent functional white charcoal board was produced with two groups of FMC 20~25% and FMC 36~60%. The latter showed best results among tested samples in two types which are #40-60type-P15%, M5%, FMC 60% and mixed type-P15%, M5%, FMC36% with non formaldehyde adhesives [MDI (M), poly vinyl acetate emulsion (P)] and three stage pressing cycle of 30-10-$30kgf/cm^2$ (1 min.-1.5 min.-6 min.). The former gave highly acceptable results in two types which are #6 over-M15%FMC25% and mixed type-M25%FMC20%. White charcoal board gave excellent in dimensional stability, gas adsorption and far-infrared emission.

• Ecology and Resilient Infrastructure
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• v.3 no.4
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• pp.231-237
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• 2016

The purpose of this study is to analyze phosphate adsorption characteristic of the filter media applied in water purification technology. And it is also to observe the removal efficiency of the technology that was developed by combining the purification abilities of filter media and the vegetation mat. The filter media, Adphos, is the subject of this study. The result of adsorption test shows that $PO_4{^{3-}-P}$ adsorption characteristics of Adphos is determined by the Langmuir isotherm model fitting and the $q_m$ (maximum adsorption amount) value is calculated as 1.162 mg/g. To verify the removal efficiency of the purification technology, a lab-scale reactor, including a 400 mm depth of filter bed filled by Adphos, was manufactured. Yellow flag Iris (Iris pseudacours L.) was planted on the vegetation bed and the coir-roll was used to fix the root of vegetation. The reactor ran 8 hours per day over 71 days, and the results of filtration experiment show that average removal efficiency of SS, T-N and T-P were calculated as 94%, 41% and 64% respectively. With these results, it was proved that the purification technology is highly effective. And for the long-time use, a maintenance guide is also required.

• Korean Chemical Engineering Research
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• v.52 no.4
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• pp.530-537
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• 2014

Moisture is a major factor causing the deteriorative physical change, microbial growth, and chemical reaction of the products. In this study, the moisture absorbing composite films have been prepared with moisture absorbing material of polyacrylic acid partial sodium salt (PAPSS) impregnated on LLDPE polymer for the functional packaging applications. The results showed that PAPSS impregnated film illustrated uniformly dispersed PAPSS particles in the LLDPE polymer matrix. The transparency of the PAPSS impregnated film decreased slightly at higher PAPSS concentrations. An increase in the PAPSS content for moisture-absorbing films showed a similar decrease in tensile strength, percent elongation at break, and tear strength. Their values of films impregnated with PAPSS of 0.5, 1, and 2% showed no significant difference. Meanwhile, 4% PAPSS films significantly decreased the values of mechanical properties compared to the films impregnated with different PAPSS levels. Values of the oxygen permeability and water vapor permeability for PAPSS impregnated films decreased significantly with greater PAPSS. The results indicate that 4% PAPSS impregnated in LLDPE films had high affinity of moisture absorbencies compared to the other films. The mathematical equation that best described the moisture sorption isotherm of each film sample was the GAB equation at $25^{\circ}C$. The crystallization and melting temperatures of PAPSS films were influenced by the addition of PAPSS material, but showed good thermal stability.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.702-708
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• 2018

Volatile organic compounds (VOCs), as a significant air pollutant, is generated mainly from the burning of fossil fuels, building materials using painting, etc. The inhalation of a certain amount of VOCs can be deleterious to human health, e.g., headaches, nausea and vomiting. In addition, it can also cause memory loss and even increase the rate of leukemia. Therefore, as one of the methods for reducing VOCs in air, polyacrylonitrile/fly ash (PAN/FA) composite nanofibrous membranes were fabricated by electrospinning. To observe their VOCs adsorption capacity, the morphological structure of PAN/FA nanofibrous mats was investigated by field emission scanning electron microscopy (FE-SEM), and the VOCs (chloroform, benzene, toluene, and xylene) adsorption capacity of PAN/FA membranes were tested by gas chromatography/mass spectrometry (GC/MS). The results indicated that the PAN nanofiber containing 40 wt. % FA powder had the smallest fiber diameter of 283 nm; they also showed the highest VOCs adsorption capacity compared to other composite membranes.

• Analytical Science and Technology
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• v.13 no.5
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• pp.608-615
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• 2000

A determination method of trace nickel and cobalt in water samples was studied and developed by adsorbing their complexes on ion exchange resin suspension. The analytical ions were formed as complexes with a ligand of APDC (ammonium pyrrolidinedithiocarbamate) and adsorbed on anion exchange resin of Dowex 2-X8. After the suspension was filtered out with membrane filter, the complexes were dissolved in HCl solution by an ultrasonic vibrator for ET-AAS determination. Several conditions were optimized as followings. pH of sample solution: 5.0, amount of ligand APDC: more than 430 times in mole ratio, the type and concentration of acid: 0.1 M HCl, and vibration time: 7 minutes. The addition of palladium in the HCl solution could improve the reproducibility and sensitivity by a matrix modification in the absorbance measurement. This procedure was applied for the analysis of three kinds of real water samples. The detection limits equivalent to 3 times standard deviation of blank were Co 0.36 ng/mL and Ni 0.27 ng/mL and recoveries in spiked samples were 99-102% for cobalt and 100-105% for nickel.

• Journal of the Korean Chemical Society
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• v.31 no.1
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• pp.45-54
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• 1987

Dowex 1-X8 resin ion exchanged with calcon carboxylic acid (CCA-Dowex 1-X8) and 2-methyl-8-hydroxyquinoline(MHQ) impregnated-Amberlite XAD-4 resin (MHQ-XAD-4) were examined for the separation and preconcentration of ferric ion from the various matrices. The stabilities of these resins were investigated, and their capacities on ferric ion were also measured. The effect of pH on the adsorption of ferric ion and matrix ions, such as Al(Ⅲ) and Ca(Ⅱ), was investigated to determine the optimun pH ranges. Separation and preconcentration of iron in aluminium foil and mineral water samples were studied by elution method with these resin columns. The recovered ions by 10ml of 2F nitric acid was determined by flame atomic spectrophotometry. SP-Sephadex C-25 column was used to separate ferrous and ferric ion in mineral water by stepwise elution with ferrozine and 1 % ascorbic acid-ferrozine solution. The concentrated and separated each ion could be determined spectrophotometrically at the analytical wavelenth of Fe(Ⅱ)-ferrozine complex (562nm).