• 해양환경안전학회지
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• 제18권2호
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• pp.67-83
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• 2012

양식활동이 활발한 반폐쇄적인 내만에서 퇴적물의 지화학적 특성을 파악하기 위하여 2010년 4월 가막만 전역의 19개 정점에서 표층 퇴적물을 채취하여 퇴적물 중의 금속(V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Cd, Hg, Pb, As), 비금속(P, Se) 및 악티늄족 중 U원소의 분포특성을 파악하였다. 또한, 퇴적물기준 및 농축계수를 이용하여 금속원소의 오염도를 평가하였다. V, Cr, Fe, Co 및 Ni 등은 석영희석 효과, Cd 및 U은 유기물 희석효과, Mn, Ag, As 및 Se는 만의 북부 및 남부해역 정점들에서 표층퇴적물의 강한 환원환경경하에서 이산화망간 및 황산염이 유기물 분해의 산화제로 이용되면서 화학적 재분배에 의해 농도분포가 결정되어지는 것으로 보여진다. 미국 퇴적물 오염 기준(SQGs)에 의한 오염평가는 As의 경우 만의 중앙부를 제외한 대부분의 정점, Ni은 전 조사정점에서 ERL을 초과하였다. 농축계수(EF)를 이용한 평가는 Ni, Ag, Cd 및 As가 평균 EF가 1을 약간 초과하는 단계를 보였으며, 이외의 성분은 1과 유사하거나 혹은 그 이하 양호한 수준을 나타내었다.

• 분석과학
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• 제28권3호
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• pp.196-203
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• 2015

셀레늄 강화 사료를 먹인 모돈에 대하여 혈청에서의 셀레늄 화학종들 즉, 무기셀레늄, 셀레노아미노산 및 셀레노단백질들을 음이온 교환과 친화 크로마토 그라피를 ICP/MS에 연결사용하여 분석하였다. 무기 셀레늄(Se⁴⁺와 Se⁶⁺)과 셀레노 아미노산들은 PRP X-100 음이온 교환 컬럼을 사용하였고 셀레노 단백질들의 경우에는 HEP 컬럼을 사용하여 SelP을 GPx+SeAlb로 부터 분리하였다. 정량분석은 후 컬럼 동위원소 희석법을 사용하여 이 들의 농도를 결정하였다. 모돈 실험군을 3 그룹으로 나누고 셀레늄이 강화된 사료(유기셀레늄 0.3 mg/kg, 0.6 mg/kg 및 무기셀레늄 0.6 mg/kg)를 4주 동안 먹였을 때 셀레늄 화학종들의 변화 및 사료와의 상관관계를 알아보았다. 셀레노 아미노산의 경우, 실험군들은 무기셀레늄 강화사료를 제외하고 대조군에 비하여 높은 농도를 보여주었다. 유기셀레늄 강화사료에서는 큰 차이를 보이지 않았다. 셀레노 단백질의 경우는 실험군 모두가 대조군에 비하여 증가를 보여주었는데 특히 SelP가 다른 단백질에 비하여 1.5 배 정도 더 크게 증가한 것으로 나타났다.

• Asian-Australasian Journal of Animal Sciences
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• 제31권12호
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• pp.1939-1945
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• 2018

Objective: This study was conducted with the objectives to examine the impacts of inorganic selenium (Se) and different types and levels of organic selenium on the serum and tissues Se status and antioxidant capacity in broiler breeders. Methods: Five hundred and forty 48-wk-old Lingnan Yellow broiler breeders were randomly assigned to 6 dietary treatments, provided same basal diet (0.04 mg/kg of Se) with 0.15 mg/kg, or 0.30 mg/kg of Se from sodium selenite (SS) or from selenium-enriched yeast (SY) or from selenomethionine (SM). The broiler breeders were slaughtered after an 8-wk experiment. Results: The results showed that SM was better than SY and SS, 0.30 mg/kg level was better than 0.15 mg/kg level in Se deposition (p<0.05) in serum, liver, kidney, pancreas and muscle; in antioxidant status, organic selenium had better effects than SS in broiler breeders (p<0.05), but SM and SY had a similar result, and 0.15 mg/kg level was better than 0.30 mg/kg (p<0.05). Conclusion: The results demonstrated the evident advantage of supplementation of broiler breeders with 0.15 mg/kg SM, which improved tissue Se concentrations and antioxidant status, and can be considered as the best selenium source.

• Journal of the korean society of oceanography
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• 제37권4호
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• pp.224-231
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• 2002

Vertical distributions of coprostanol (5$\beta$-cholestan-3$\beta$-ol) and other sterols were investigated in the intertidal sediment of Shinbul island in the Han River estuary to estimate the short-term variations of fecal contamination in association with reclamation activity which caused a construction of tidal barrier and emigration of residents from the island. Quantitative contributions of coprostanol in total sterol (9.87-15.84%) and in total organic carbon (82.0-157.7 $\mu\textrm{g}$ g$^{-1}$ OC) implied that a substantial amount of organic matter associated with fecal pollutants was introduced into the sediment. The highest contribution of coprostanol to organic carbon that was observed between 0.3-0.9 cm depth seemed to be associated with increased human activities for the reclamation project of the island. The ratio of coprostanol to organic carbon decreased within 0.3 cm depth, which indicated decreased fecal contamination after the emigration of residents from the island. The results suggested that measurement of coprostanol could relevantly reflect short-term fluctuation of fecal contamination in the sediment of the Han River estuary.

• 한국환경보건학회지
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• 제32권1호
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• pp.96-101
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• 2006

Chlorination inhibition on the organic removal activity of activated sludge microorganism was investigated in this study. It is well known that chlorination improves the settleability of filamentous bulking sludge through the selective impediment of filamentous microorganisms. However, it is based on the declination of effluent water quality after actual chlorination in dairy wastewater treatment plant. In case of the activated sludge which was exposed in the suggested concentration of chlorine $7.5\;mgCl_2/gVSS/day$ for the filamentous bulking control, decrease of organic uptake rate of $4.9\~24.0\%$, and dentrification rate of $24.8\~30.3\%$ ware shown in comparison to the control group which was not reacted with chlorine. As a result of comparing floc size of activated sludge microorganism, the average of floc diameter in the chlorine exposed group was $150\;{\mu}m$, which displays $25\%$ decrease compared with the control group.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.69-69
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• 2013

In the area of artificial photosynthesis, particularly for the generation of hydrogen form water, much attention has been paid on organic-inorganic hybrid system. Most of all, a dye/TiO2-combined system has been suggested and its potential utility was well manifested. However, due to its complicated nature of charge interactions in between dye and TiO2 -interface there remains a great challenge to establish the charge-activity relationship, per se light driven charge generation and recombination kinetics with respect to the amount of hydrogen produced. Further complexity of that hybrid system has been witnessed when sacrificial donor and aqueous media are considered. To unveil the operating mechanism on such a dye/TiO2-combined system, we have prepared organic dyes suitable to account for the effect of sacrificial donor as well as water interactions, and prepared the typical dye-grafted TiO2 films to investigate charge-activity relationship. Femtosecond flash photolysis clearly defined the dye effects anchored on to the TiO2 platform. In addition, photodynamic data contemplated well to the dye orientation proposed by the DFT calculations. Recent findings provide fundamental understanding on the dye-grafted TiO2 system and establish a firm background how future dye-sensitized organic-inorganic hybrid system can be designed for the light driven hydrogen generation from water.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2013년도 제45회 하계 정기학술대회 초록집
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• pp.150.2-150.2
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• 2013

We elucidate the mechanism of the self-assembled organic layer formation at the organic/metal interface of hexaaza-triphenylene-hexacarbonitrile (HATCN)/Au(111) by first-principles calculations and Lowtemperature scanning tunneling microscope (STM). In this work, we used HATCN to deposit organic material which is well known as an efficient OLED charge generation material. Low-temperature STM measurements revealed that self-assembled hexagonal porous structure is formed at terraces of Au(111). We also found that the hexagonal porous structure has chirality and forms only small (<1000 $nm^2$) phaseseparated chiral domains that can easily change their chiral phase in subsequence STM images at 80 K. To explain the mechanism of these observation, we calculated the molecular-molecular and molecule-surface interaction energies by using density functional theory method. We found that the change of their chiral phase resulted from the competition between the two energies. These results have not only verified our experimental observations, but also revealed the delicate balance between different interactions that caused the self-assembed structures at the surface.

• Membrane and Water Treatment
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• 제14권3호
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• pp.141-146
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• 2023

Algal organic matters (AOMs) are challenging to remove using traditional water treatment methods. Additionally, they are recognized as disinfection by product (DBP) precursors during the chlorination process. These compounds have the potential to seriously harm aquatic creatures. Despite the fact that AOMs and DBPs formed from algae can harm aquatic species by impairing their cognitive function and causing behavioral problems, only a few studies on the effects of AOMs and associated DBPs have been conducted. To assess the impact of extracellular organic materials (EOMs) produced by three different hazardous algal species and the chlorinated EOMs on zebrafish, this study used fish acute embryo toxicity (FET) and cognitive function tests. With rising EOM concentrations, the embryo's survival rate and mental capacity both declined. Of the three algal species, the embryo exposed to Microcystis aeruginosa EOM exhibited the lowest survival rate. On the other hand, the embryo exposed to EOMs following chlorination demonstrated a drop in CT values in both the survival rate and cognitive ability. These findings imply that EOMs and EOMs treated with chlorine may have detrimental effects on aquatic life. Therefore, an effective EOM management is needed in aquatic environment.

• Journal of Microbiology and Biotechnology
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• 제27권12호
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• pp.2151-2155
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• 2017

Bacteriophages have gained substantial attention as biocontrol and biorecognition agents, substituting antibodies. In this study, a Salmonella Enteritidis-specific bacteriophage, KFS-SE1, was isolated, identified, and characterized. This Siphoviridae phage infects S. Enteritidis with high specificity. This phage is highly stable under various pH (5-11), temperature ($4-60^{\circ}C$), and organic solvent conditions. The KFS-SE1 genome consisted of 59,715 bp with 73 predicted open reading frames and 57.14% GC content; it had a complete set of genes required for phage reconstruction. Comparative phylogenetic analysis of KFS-SE1 revealed that it was very similar to the other Salmonella phages in the Siphoviridae family. These characteristics suggest that KFS-SE1 with its high specificity and host lysis activity toward S. Enteritidis may have various potential applications.

• Current Photovoltaic Research
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• 제5권4호
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• pp.140-144
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• 2017

$CuSbS_2$ (CAS) and $CuSbSe_2$ (CASe) nanocrystals (NCs), which consist of earth-abundant elements, were synthesized by a mechanochemical method. Elemental precursors such as copper, antimony, sulfur, and selenium were used without adding any organic solvents or additives. The NCs were synthesized by milling for a few hours. The sudden phase changes occurred by self-ignition and propagation, as previously observed in other mechanochemical synthetic processes. The XRD, Raman, and TEM analysis were carried out to determine the crystallinity and secondary phase of the as-synthesized CAS and CASe NCs, confirming the phase-pure synthesis of CAS and CASe. Optical properties were investigated by UV-Vis spectroscopy and it was observed that the band gap energies were about 1.1 and 1.5 eV, respectively for CAS and CASe, suggesting the potential for the use as solar cell materials. The NC colloids dispersed in anhydrous ethanol were prepared and coated on Mo substrates by a facile doctor-blade method. The investigation on the solar cell properties of the as-synthesized materials is underway.