• Journal of Plant Biotechnology
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• v.50
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• pp.76-81
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• 2023

As cultured plant cells can grow in high oxidative stress conditions, they form an excellent system to study antioxidant mechanisms and the mass production of antioxidants. Oxidative stress is a major cause of damage in plants exposed to various types of environmental stress, including heavy metals, such as cadmium (Cd). Heavy metal accumulation can interfere with many cell functions and plant growth. To evaluate the contribution of oxidative stress to Cd-induced toxicity, cultured sweetpotato (Ipomoea batatas) cells were treated with increasing concentrations of Cd (0, 10, 25, and 50 μM) and cultured further. Cell growth was significantly inhibited by 25 and 50 μM of Cd, and the total protein content increased with 50 μM of Cd. Additionally, the activity of peroxidase (POD) and ascorbate peroxidase (APX), antioxidant enzymes that remove hydrogen peroxide (a reactive oxygen species), increased in the cells after treatment with 50 μM of Cd. The expression analysis of POD, APX, and peroxiredoxin (PRX) isolated from sweetpotato cultured cells in a previous study revealed the differential expression of POD in response to Cd. In this study, the expression levels of several acidic POD (swpa2, swpa3, and swpa4) and basal POD (swpb1, swpb2, and swpb3) genes were increased in Cd-treated cultured cells. These results indicate that Cd-mediated oxidative stress is closely linked to improved POD-mediated antioxidant defense capacity in sweetpotato suspension-cultured cells.

• Tuberculosis and Respiratory Diseases
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• v.81 no.4
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• pp.351-351
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• 2018

• Bulletin of the Korean Chemical Society
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• v.34 no.3
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• pp.856-862
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• 2013

The photoanode electrode of $TiO_2$ nanotubes (NTs) anchored with ZnS/CdSSe/CdS quantum dots (QDs) was prepared by anodization of Ti metal and successive ionic layer adsorption and reaction (SILAR) procedure. The tuning of the band gap of CdSSe was done with controlled composition of Cd, S, or Se during the SILAR. A ladder-like energy structure suitable for carrier transfer was attained with the photoanode electrode. The power conversion efficiency (PCE) of our solar cell fabricated with the regular array of $TiO_2$ NTs anchored with CdSSe/CdS or CdSe/CdS QDs [i.e., (CdSSe/CdS/$TiO_2NTs$) or (CdSe/CdS/$TiO_2NTs$)] was PCE = 3.49% and 2.81% under the illumination at 100 mW/$cm^2$, respectively. To protect the photocorrosion of our solar cell from the electrolyte and to suppress carrier recombination, ZnS was introduced onto CdSSe/CdS. The PCE of our solar cell with the structure of a photoanode electrode, (ZnS/CdSSe/CdS/$TiO_2$ NTs/Ti) was 4.67% under illumination at 100 mW/$cm^2$.

• The Korean Journal of Ecology
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• v.13 no.2
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• pp.143-148
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• 1990

During the autumn of 1985, the stem cortex of Salix pseudo-lasiogyne on the street sides in Seoul city was collected by a cork borer. The contents of S, Pb and Cd in this sample were determined. The ranges of S, Pb and Cd contents in all the samples were 0.98-3.46$\mu$/g, 0.77-1.81$\mu$g/g and 0.12-0.28$\mu$/g, respectively. Areas which slowed the highest level of S, Pb and Cd in the stem cortex were Yongon-dong, Yongdungp o, Ulchiro, Ch ongnyangni, Shinch on and Suyu-dong, Yongdungp o, Ulchiro and Ch ongnyangni, and Yongon-dong, Yongdungp o and Ch ongnyangni, respectively

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.05a
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• pp.169-172
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• 2005

본 연구의 목적은 ${\beta}-CD$를 가교화 시켜 육가공 제품의 주원료인 lard의 cholesterol을 효과적으로 제거하기 위한 최적조건 확립이다. 따라서 adipic acid로 가교화한 ${\beta}-CD$를 이용해 lard에서 cholesterol을 제거하고 더 높은 효율을 찾기 위하여 실시되었다. 가교화 ${\beta}-CD$를 이용해 lard에서 cholesterol 제거 실험결과의 최적 조건은 lard : distilled water=1:1, 가교화 ${\beta}-CD$ 5%를 첨가, 교반온도 $40^{\circ}C$, 교반시간 10분, 교반속도 150rpm으로 실험한 결과 cholesterol 제거율이 평균 81.6%이었다. 이 실험의 결과 가교화 ${\beta}-CD$로 lard의 cholesterol 제거 최적조건을 규명하고 이는 콜레스테롤을 저하시킨 육가공 제품의 생산 가능성을 시사하였다.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2004.05a
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• pp.341-344
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• 2004

본 연구의 목적은 cholesterol를 가교화 시켜 우유 및 유제품의 cholesterol을 효과적으로 제거하고, 이들의 재활용이 용이하게 되어지는 것을 규명하는데 있으며, 이를 이용해 cholesterol을 제거하고 재활용 하는데 문제가 되었던 점을 고려해 가교화 ${\beta}$-CD를 이용해 우유 및 유제품에서 cholesterol을 제거하고 재활용의 더 높은 효율을 위하여 실시되었다. 가교화 ${\beta}$-CD를 이용해 우유에서 cholesterol 제거 실험결과의 최적 조건은 가교화 ${\beta}$-CD 1%를 첨가해 교반온도 $10^{\circ}C$, 교반시간 10분, 교반속도 400rpm으로 실험한 결과 cholesterol 제거율이 평균 81.6%이었다. 또한 가교화 ${\beta}$-CD의 재활용율은 92%로 나타났다. 이 실험의 결과 ${\beta}$-CD의 가교화가 우유의 cholesterol제거와 재활용 면에서 긍정적인 것으로 사료되며 산업화의 가능성을 시사하였다.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.374-374
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• 2011

Cu(In,Ga)Se2 (CIGS) 박막 태양전지는 일반적으로 Soda lime glass/Mo/CIGS/CdS/ZnO/ITO/Al의 구조로 제작된다. 태양전지는 p형과 n형 반도체의 접합에 의해서 동작을 하게 되며, CIGS 박막 태양전지에서는 p형으로 CIGS 박막과 n형으로 CdS 박막이 사용된다. CIGS 박막태양전지에서는 p형과 n형이 서로 다른 물질로 이루어진 이종접합을 이루게 되고, 계면에서의 밴드가 어떻게 형성이 되느냐에 따라 태양전지 성능에 영향을 미치게 된다. p형의 CIGS 박막은 주로 다단계 증발법에 의해 형성되고 3단계 공정조건에 의해 계면의 특성에 많은 영향을 미치게 된다. n형의 CdS 박막은 주로 chemical bath deposition (CBD) 법에 의해 제작된다. 이렇게 제작되는 CBD-CdS는 시약의 농도, pH (수소이온농도), 박막 형성시의 온도 등의 조건에 따라 특성이 변하게 된다. 본 논문에서는 3단계 공정시간을 변화시켜 제작된 CIGS 박막 위에 CBD-CdS 증착 조건 중 thiourea 의 농도를 변화시켜 CIGS 태양전지를 제작하고 그에 따른 특성을 살펴보았다. CIGS 박막은 3단계 공정시간을 490초와 360초로 하여 제작하였고, CdS 박막은 thiourea 농도를 각각 0.025 M과 0.05 M, 0.074 M, 0.1 M로 변화시켜가며 제작하였다. 제작된 CIGS 박막 태양전지는 CIGS 3단계 공정시간과 thiourea의 조건에 따라 최고 15.81%, 최저 14.13%로 나타내었다. 또한, 외부양자효율을 측정하여 제작된 CIGS 박막 태양전지의 파장에 따른 특성을 비교하였다.

• Horticultural Science & Technology
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• v.32 no.2
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• pp.157-164
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• 2014

Objective of this research was to develop root media containing expanded rice hull (ERH) and carbonized rice hull (CRH). To achieve this, the physico chemical properties of two materials were analysed and blended with peatmoss (PM) or coir dust (CD) with various ratio. Based on the physical properties of the blended materials, 4 root media were selected for future experiment. After the analysis of pH and EC of the selected root media, the kinds and amount of pre-planting nutrient charge fertilizers (PNCF) incorporated into each root medium were varied, and then, final chemical properties of the root media were analysed. The total porosity (TP), container capacity (CC), and air-filled porosity (AFP) were 81.3%. 39.9%, and 41.4% in ERH and 77.6%, 64.1%, and 13.5% in CRH, respectively. The percentage of easily available water (EAW, from CC to 4.90 kPa tension) and buffering water (BW, 4.91-9.81 kPa tension) were 11.37% and 5.27%, in ERH and 17.26% and 14.28% in CRH, respectively. The pH of ERH was 7.1, but it was extremely high in CRH such as 11.2. The EC and CEC were $1.31dS{\cdot}m^{-1}$ and $12.1meq{\cdot}100g^{-1}$ in ERH and $6.53dS{\cdot}m^{-1}$ and CEC 7.79 $meq{\cdot}100g^{-1}$ in CRH, respectively. The ranges of TP, CC and AFP in 4 selected media (PM + ERH, 6:4, v/v; CD + ERH, 8:2; PM + CRH, 7:3; CD+CRH 6:4) were 89.2-90.3%, 67.3-81.8%, and 8.3-21.9%, respectively. The pHs and ECs in root media containing peatmoss such as PM + ERH (6:4) and PM + CRH (7:3) were 4.0-4.3 and $0.33-0.365dS{\cdot}m^{-1}$, whereas those of CD + CRH were 7.4-7.9 and $1.282dS{\cdot}m^{-1}$. The pHs and ECs, however, analysed before and after the incorporation of PNCF in each root medium were not significant different. This result indicated that the incorporated fertilizers in PNCF to adjust medium pH did not dissolve enough to influence medium pH, but it is very normal in root media containing dolomitic lime and sulfur powder in adjusting pH. The Information obtained in this study may facilitate an effective formulation of root media containing rice hulls.

• Fire Science and Engineering
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• v.34 no.1
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• pp.55-65
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• 2020

In this study, the ISO 5660 and ISO 5659 combustion tests were conducted with synthetic resin conduits (CD, VE) and metal conduit (ST) used for wiring work in electrical facilities, which can be installed in ceiling concealed places. Then, fire spreading and evacuation risks were analyzed based on the measured data. In the ISO 5660 test, CD of 120.5 MJ/㎡, VE of 81.9 MJ/㎡, and ST of 4.9 MJ/㎡ were measured. In the ISO 5659 test, the CD 1320, VE 731, and ST 102 were measured, and then the maximum smoke densities were measured for CD 605 s, VE 740 s, and ST 1,200 s. In terms of fire spreading and evacuation risk, the CD conduit, VE conduit, and ST conduit were in order. In the fire spreading risk analysis, total heat emission was calculated as 4,820 MJ/㎡, 4,267 MJ/㎡, and 196 MJ/㎡ for CD, VE, and ST, respectively. Evacuation risk analysis shows at transmittance of 89%, CD is 127 s, VE is 35 s, and ST is 969 s. At transmittance of 79%, representing almost invisible concentration, CD is 157 s and VE is 50 s. The CD and VE conduits had a high fire spreading and evacuation risks, while the ST conduit had little effect on fire spreading and evacuation risk.

• Journal of Soil and Groundwater Environment
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• v.8 no.2
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• pp.87-91
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• 2003

This study was carried out to investigate the heavy metal distributions of soils in the vicinity of Shi-Hwa industrial complex region, where the air pollutants from industrial area could affect the soil environment of near residential and green areas. The ranges of contents of As, Cd, Co, Cr, Cu, Hg, Ni, Pb and Zn in soils were 0.58~3.81, ND~0.91, 0.15~6.33, ND~l.86, 0.14~110.27, ND~l.17, 0.04~10.59, 1.16~86.48 and 1.83~212.65 mg/kg, respectively. For all industrial, residential and green areas, the heavy metal contents were much lower than the standard of Korean Soil Environmental Preservation Act or the critical concentration which phytotoxicity is considered to be possible. Mean values of contents of As were similar in industrial, residential and green areas. However, the mean values of contents of Cd and Cr in industrial area were higher 10 and 5 times than those in residential and green area, respectively. And also the mean values of contents of Co, Cu, Hg, Ni, Pb and Zn in industrial area were higher 2~3 times than those in residential and green area.