• Clinical and Experimental Pediatrics
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• v.46 no.8
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• pp.763-768
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• 2003

Purpose : This study was conducted to investigate the pulmonary cellular profiles and IL-8 levels in patients with post-measles wheezing. Methods : Twelve previously healthy infants with a minimum of three episodes of wheezing after measles pneumonia(Measles wheezing, median age, 1.3 years) were recruited by a retrospective examination of hospital records. They underwent bronchoalveolar lavage(BAL) with flexible bronchoscopy, and high-resolution computed tomography(HRCT) with a mean six(1-15) months interval. Comparisons were made with seven normal controls(Control, median age : 7.4 years). BAL cell counts and differentials were determined. IL-8 levels also were measured by ELISA. Results : The BAL cellular profiles were characterized by a significantly increased percentage of neutrophils in the Measles wheezing group(median 16.0%) compared to the control group(median 3.8 %)(P<0.01). IL-8 levels were markedly increased in the Measles wheezing group($mean{\pm}SD$, $512.7{\pm}324.0pg/mL$) compared to the control group($41.7{\pm}67.7pg/mL$)(P<0.01). Furthermore, IL-8 levels correlated significantly(r=0.816, P=0.001) with neutrophil percentages in BAL fluids in the Measles wheezing group. Abnormal HRCT findings were mosaic perfusion, bronchiectasis, bronchial wall thickening, and decreased vascularity. Conclusion : These results suggest that pulmonary neutrophils and IL-8 may play an important role in the pathogenesis of the post-measles wheezing.

• Korean Journal of Microbiology
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• v.49 no.3
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• pp.253-261
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• 2013

The purpose of this study was to investigate the aflatoxin $B_1$ binding of lactic acid bacteria (LAB) isolated from Korean traditional soybean paste and to evaluate the effect of incubation conditions and physico-chemical factors on the binding ability of LAB to this mutagen. The amount of aflatoxin $B_1$ bound by Enterococcus faecium DJ22, Lactobacillus fermentum DJ35, Lactobacillus rhamnosus DJ42, and Lactobacillus pentosus DJ47 was strain specific with the percent bound ranging from 19.3% to 52.1%. However, Enterococcus faecalis DJ14, Lactobacillus panis DJ29, and Pediococcus halophilus DJ50 strains did not exhibit any of the binding ability to aflatoxin $B_1$. For most strains, the binding ability was significantly affected by the environmental conditions such as the aflatoxin $B_1$ level, incubation time and temperature, and the initial cell count of LAB. The stability of the aflatoxin $B_1$-bacteria complexes was significantly more unstable after washing. In addition, the binding stability between viable and nonviable cells was not statistically significant. Treatment with heating, acidic pH, ${\alpha}$-amylase, protease, lysozyme, or sodium metaperiodate caused a significant (P<0.05) decrease in aflatoxin $B_1$ binding for the tested strains, suggesting that carbohydrates or proteins in the cell walls may be involved in aflatoxin $B_1$ binding ability. Since the aflatoxin $B_1$ binding of LAB was significantly reduced (P<0.05) by the pretreatment of the urea, the binding force observed in this study may have resulted from hydrophobic interaction.

• Journal of Korean Society of Environmental Engineers
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• v.38 no.10
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• pp.543-550
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• 2016

Amine-type PP-g-VBC-EDA adsorbent, which possesses anionic exchangeable function, was prepared through photoinduced graft polymerization of vinylbenzyl chloride (VBC) onto polypropylene non-woven fabric and subsequent amination reaction using ethylenediamine (EDA). Adsorption characteristics of anionic nutrients on the PP-g-VBC-EDA adsorbent have been studied by batch adsorption experiments. The equilibrium data well fitted the Langmuir isotherm model, and the maximum monolayer sorption capacity was found to be 59.9 mg/g for $NO_3-N$ and 111.4 mg/g for $PO_4-P$. The adsorption energies were higher than 8 kJ/mol indicating anion-exchange process as the primary adsorption mechanism. The pseudo-second order kinetic model described well the kinetic data and resulted in the activation energy of 9.8-36.7 kJ/mol suggesting that the overall rates of $NO_3-N$ and $PO_4-P$ adsorption are controlled by the chemical process. Thermodynamic parameters such as ${\Delta}G^o$, ${\Delta}H^o$ and ${\Delta}S^o$ indicated that the adsorption nature of PP-g-VBC-EDA for anionic nutrients is spontaneous and exothermic. The PP-g-VBC-EDA could be regenerated by washing with 0.1 N HCl.

• Journal of Korean Society of Environmental Engineers
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• v.35 no.11
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• pp.785-794
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• 2013

Combined sewer overflows during rainfall events contain sewer sediments and surface pollutants. This can cause significant chemical, physical and biological problems to receiving watershed. However, there are no method that can commonly apply to decide criteria for controlling the pollutant load. In this study, it sets up the reduction goals of combined sewer overflow through long-term simulation using the rainfall-runoff model. From a review of domestic and foreign management standard of combined sewer overflow for this, it makes decision that 60% (phase 1), 85% (phase 2) of total pollutant load and frequency per year for reduction goals is more proper. Also, the result of analyzing long-term simulation (minimum 10 years) applied to research basin indicates that reduction goals of BOD pollutant load are 1,123 kg (phase 1) and 2,374 kg (phase 2), and overflow volumes for research objective achievement are $11,685m^3$ (phase 1) and $24,701m^3$ (phase 2).

• Journal of Conservation Science
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• v.27 no.4
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• pp.441-450
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• 2011

This study investigated potential damages and conservation methods for the ceramics (without glaze) by examination of physical and chemical effects from the burial environments. For this study, pottery samples excavated from Daejeon Hakha, Asan Eumbong, Hwasung Sogeunsan and Kongju Haengbokdosi were examined with released ions and extraction through desalination. The result showed that the ion inflow into the ceramics was dependent upon the porosity and the absorption of ceramics. The high temperature fired ceramics (over $1,000^{\circ}C$) have low porosity and absorption, therefore almost no salt infiltration during the burial period. However, low temperature fired ceramics (under $800^{\circ}C$) have high porosity and absorption, and most of salts were removed during the desalination. The 40 to 60% of salts were removed in two days and 60 to 80% of slats were released in a week. Furthermore, fertilizer residues such as $K_2SO_4$, in soils were detected in the ceramcis. Also the characteristics of buried soil affected ion infiltration into ceramics. Ceramics buried in sandy soil had relatively less ion contents from buried environments than those in clayey soil. Therefore, low temperature fired ceramics could do not only cleaning but also desalination if it is necessary, and the period could be decided to the condition of ceramics.

• Journal of the Korean Chemical Society
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• v.48 no.6
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• pp.590-598
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• 2004

The preconcentration and determination of trace Cu(II) and Pb(II) on calcium alginate beads in aqueous solution were studied. A calcium alginate beads were prepared by adding an alginic acid to sample solution contained Ca(II). Some following conditions were optimized: the pH of sample solution, amount of alginic acid, and stirring time for effective adsorption; the type and concentration of acid, and sonication time in an ultrasonic vibrator for the perfect de-sorption. A sample solution was prepared with Cu(II) and Pb(II) in DI water. And Ca(II) and ethanol was added into the sample solution. The pH of the final sample solution was controlled with buffer solution. The alginic acid were dispersed in the sample solution by a magnetic stirrer. This mixture was stored in room temperature for 30 min to form a calcium alginate. After the beads were filtered and washed on a membrane filter, the analytes were redissolved from the beads by an ultrasonic vibration of 10 minutes in 1.0M $HNO_3$ solution. The effect of diverse ions on the adsorption of analytes were studied. This procedure was applied for the analysis of two real samples. The recoveries in spiked samples were $90.4{\sim}104.3%$ for analytes.

• Journal of Wetlands Research
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• v.11 no.1
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• pp.115-121
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• 2009

The hybrid constructed wetland(HCW) as tertiary treatment process of a bio industrial wastewater treatment plant was employed to estimate applications for the reuse of final effluent. Raw wastewater was sequently treated through chemical and biological treatment processes and the biologically treated water was flowed into the HCW. The HCW system was composed of two constructed wetlands connected in series; The one is the aerobic constructed wetland with natural air draft system whose driving force for air supply was the difference between the temperature of the air inside the wetland and the ambient air, and the other is the anaerobic/anoxic constructed wetland. Average influent concentrations of BOD, SS, T-N and T-P in the HCW were 53mg/L, 48mg/L, 34mg/L and 3mg/L, respectively. After being treated at HCW, final effluent concentrations of BOD, SS, T-N and T-P were 2.3mg/L, 1.2mg/L, 7.95mg/L and 0.83mg/L, respectively. Referring to a reuse standard for a sewage wastewater, final effluent could sufficiently be reuse as landscaping, washing or agriculture water. HCW system with the aerobic/anaerobic combined constructed wetland could be achieved a high removal efficiency because each constructed wetland was functionalized to be removed efficiently organics, nitrogen and phosphorus. HCW system could be estimated to be successful application as tertiary treatment process of a various industrial and municipal wastewater.

• Proceedings of the Korean Vacuum Society Conference
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• 2010.02a
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• pp.161-161
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• 2010

InAsSb alloy system 은 HgCdTe 를 대체하는 적외선 광소자 및 검출기 등에 응용이 가능한 유망한 물질이지만 정확한 유전함수 및 전이점의 연구는 미흡한 실정이다. 본 연구에서는 타원 편광 분석법을 이용하여 1.5 ~ 6 eV 의 분광 영역에서 As 조성비를 각기 (x = 0, 0.127, 0.337, 0.491, 0.726 및 1.00) 다르게 한 $InAs_xSb_{1-x}$ alloy의 유전함수를 측정하였다. 또한 표면에 자연산화막을 제거하기 위하여 Methanol 과 DI Water 로 표면을 세척 한 후 $NH_4OH$, Br in Methanol, HCl 등으로 적절한 화학적 에칭을 하여 산화막을 제거함으로서 순수한 InAsSb 의 유전함수를 측정할 수 있었다. 측정된 InAsSb 유전함수를 Standard analytic critical point line shape 방법으로 As 조성비에 따른 에너지 전이점을 얻을 수 있었다. 또한 얻어진 에너지 전이점 값을 이용하여 linear augmented Slater-type orbital 방법으로 전자 밴드 구조 계산을 하였고, 이를 바탕으로 $E_0$, $E_1$, $E_2$ 전이점 지역의 여러 전이점 ($E_1$, $E_1+\Delta_1$, $E_0'$, $E_0'+\Delta_0'$, $E_2$, $E_2+\Delta_2$, $E_2'$, $E_2'+\Delta_2$, $E_1'$) 의 특성을 정확히 정의할 수 있었다. 또한 As 조성비가 증가하면서 $E_2$, $E_2+\Delta_2$, $E_2'$, $E_2'+\Delta_2$ 전이점들이 서로 교차 되는 것을 발견하였고, 저온에서만 관측이 가능하였던 InSb 의 두 saddle-point (${\Delta_5}^{cu}-{\Delta_5}^{vu}$, ${\Delta_5}^{cl}-{\Delta_5}^{vu}$)를 상온에서 찾아내었다. 타원 편광 분석법을 이용한 전이점 연구 및 물성 분석은 InAsSb alloy 의 광학적 데이터베이스를 확보하는 성과와 더불어 새로운 디바이스기술 및 광통신 산업에도 유용한 정보가 될 것이다.

• Applied Chemistry for Engineering
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• v.29 no.2
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• pp.229-236
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• 2018

A customized cleaning agent was investigated for improving the performance decreased by the pollution of collecting plates in an electric fume collector (EFC) which was developed and applied for the purification of effluent gas including oil mist from the textile industry. The pollutants on the surface of collecting plates were blackened by the condensation of oil mist for a long time and difficult to remove by general cleaning agents. The composition of an optimized cleaning agent consisted of alkali, alcohol, glycol and non-ionic surfactant sources was determined by considering the pollutant properties and effect on the damage of the basic metal of collecting plate and so on. The developed cleaning agent solution diluted by 9.1% was applied to the field test, and also the pollutants strongly adhered on collecting plate surfaces were successfully removed by a simple spraying method. The effluent gas purification efficiency of EFC increased significantly by cleaning of collecting plates.

• Korean Chemical Engineering Research
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• v.43 no.1
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• pp.76-79
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• 2005

Dry etching of NiFe, NiFeCo, and Ta for magnetic random access memory (MRAM) by inductively coupled plasmas (ICPs) of $Cl_2/Ar$ has been carried out. NiFe and NiFeCo showed maximum etch rates at a particular ICP source power, but the etch rate of Ta increased with the ICP source power. The etch rates of the magnetic thin films increased with the RF chuck power, but decreased with the operating pressure and the $Cl_2$ concentration. To avoid a corrosion problem by chlorine, the etched samples were rinsed with de-ionized water for 5 minutes after etching. The etch profile showed a clean and smooth surface at 50% $Cl_2$ concentration.