• 대한환경공학회지
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• 제22권11호
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• pp.2067-2076
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• 2000

모사 고온석탄가스로부터 황화수소를 제거하기 위해 망간계 탈황제(MT, MFT)에 대한 실험을 수행하였다. 망간계 탈황제의 황화수소 제거효율과 탈황제의 물리적 특성을 파악하기 위해 각각 고정층 반응기와 attrition tester를 사용하여 실험하였다. 마멸저항에 대한 실험결과, 벤토나이트를 5% 함유한 탈황제가 2%를 함유한 탈황제보다 마멸저항이 컸으며 또한 경화온도가 높을수록 마멸저항이 큰 것으로 나타났다. 반응온도, 황화수소농도, 그리고 공간속도가 황화수소 제거효율에 미치는 영향을 조사한 결과, MT와 MFT 탈황제 모두 $450^{\circ}C$에서는 황화수소를 5,100ppmv에서 20ppmv까지 제거할 수 있었고, $550{\sim}650^{\circ}C$에서는30~65ppmv까지 제거할 수 있었으며, 공간속도가 증가함에 따라 파과시간은 감소하였다.

• 약학회지
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• 제56권6호
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• pp.390-394
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• 2012

A series of new pyridazinyl sulfoxides 3a~e and pyridazinyl sulfones 4a were synthesized for development of candidates to retain anticancer activity. The utility of sulfoxides and sulfones in both laboratory and industrial practice was quickly recognized, and these species have been extensively utilized, including as pharmaceutical intermediates and anticancer agents. Alkylthiopyridazines 2a~e were prepared from the 3,6-dichloropyridazine using allylthiolation with alkyl mercaptan. Sulfides could be oxidized to sulfoxides or sulfones using 1~3 equivalents of hydrogen peroxide as an oxidant. The oxidation of sulfoxides to sulfones was also accomplished with aqueous hydrogen peroxide. Formation of 3a~e and 4a was undertaken with stirring using 35% hydrogen peroxide at room temperature in acetic acid for 18~72 h. Synthetic compounds were identified using NMR spectrum.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제3권2호
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• pp.131-136
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• 1999

The solubility of H2S is an important parameter for modeling H2S absorption. Since the direct measurement of H2S solubility in aqueous amine solutions is impossible, this work initially attempted to develop an H2S analogy method, however, this was unsuccessful. Consequently, H2S solubilities were measured in aqueous amines which were completely protonated with HCI over a temperature range of 25-60℃. The solvents investigated in this work included 0-50% aqueous solutions of methyldiethanolamine and diethanolamine. Thereafter, a new empirical correlation was developed that can predict Henry's constant for H2S using only the solubility of H2S in water and t도 molecular weight of the aqueous solvent.

• 공업화학
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• 제29권6호
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• pp.765-771
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• 2018

본 연구에서는 각종 환경기초시설에서 발생하는 악취 유발물질 중 $H_2S$를 처리하기 위한 하수슬러지 기반 흡착제의 흡착성능 증진을 위해 제조조건 중 탄화조건 최적화에 대한 연구를 수행하였다. 적용되는 흡착제는 하수처리장에서 발생하는 슬러지를 온도 및 승온속도와 같은 탄화조건을 달리하여 제조하였으며, 흡착제의 물리적 특성과 흡착성능과의 상관관계를 확인하였다. 실험결과 $10^{\circ}C/min$의 승온속도로 $900^{\circ}C$의 온도에서 탄화과정을 거친 슬러지의 흡착성능이 가장 우수하였으며, SEM, BET 분석을 통해 비표면적 및 기공특성(기공크기, 부피)이 흡착성능의 주요 인자임을 확인하였다. 최적 탄화조건 흡착제의 흡착성능을 증진시키기 위해 K 이온을 담지하였으나, 하수슬러지 기반 흡착제의 경우 큰 영향이 없는 것으로 확인하였다.

• 한국양식학회지
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• 제13권1호
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• pp.39-46
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• 2000

우리나라의 대하양식은 먹이생물이 대체로 풍부한 연안 및 만을 중심으로 제방을 쌓거나 폐쇄된 염전 등을 이용하여 극히 한정된 장송에서 실시되고 있다. 본 조사 대하 양식장인 남해의 갈화 양식장은 조석차이를 이용한 해수교환이 주기적으로 실시되고 있으나, 서해의 운호 양식장은 단지 양수에 의한 해수보충이 가끔 실시되고 있을 뿐이다. 따라서, 본 연구는 갈화와 운호양식장의 환경특성을 파악하였고, 이에 따른 성장을 비교.검토하다. 갈화양식자의 저질성상은 사질이 약 70%를 차지한데 비해 운호 양식장은 대부분 펄이 차지하고 있었다. 저질중의 황화물은 갈화 양식장에서 1.8mgS/g-dry, 운호 양식장에서 4.7mgS/g-dry가 측정되어 약 3배의 차이를 나타내었다. 해수중의 ammonia-N 및 $H_2S$ 농도는 갈화 양식장에서 각각 0.10mg/${\ell}$ 및 10.8 ${\mu}$g/${\ell}$가 측정된 반면, 운호 양식장에서는 약 2배 이상 높은 0.31mg/l 및 21.2${\mu}$g/${\ell}$이 측정되었다. 또한, DO는 7월부터 8월에 걸쳐 갈화 양식장에서 6.0mg/${\ell}$이하, 운호 양식장에서는 5.0mg/${\ell}$이하가 관찰되었다. 대하의 체장과 체중은 10월 갈화 양식장의 158.2mm 및 28.9g에 비해 운호 양식장에서는 138.3mm 및 22.9g로 유의하게 낮은 성장을 보였다. 또한, 대하의 일일 성장률도 양식기간을 통해 갈화 양식장에 비해 운호 양식장에서 낮게 나타났다/ 따라서, 운호 양식장의 저층수에서 측정된 ammonia-N, $H_2S$ 및 DO는 대하의 성장에 영향을 미쳤다는 것을 의미한다.

• 한국수소및신에너지학회논문집
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• 제27권6호
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• pp.670-676
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• 2016

Hydrogen town in Republic of Korea was established in 2013. Hydrogen as a byproduct produced by various processes of factories is used in hydrogen town facilities. As cell performance is affected by contaminations in fuel gas, various standards about impurities of fuel have been determined by many countries. This study shows performance degradation of single cell with impurities concentrations. Traces of carbon monoxide (CO) and hydrogen sulfide ($H_2S$)can cause considerable cell performance losses. For comparing the performances by poisoning of CO, acceleration test, I-V curve, constant current are performed. Both the CO and $H_2S$ poisoning rate are a function of their concentration. With the higher concentrations the higher poisoning rates are observed. And, it was confirmed that, oxidation behavior and side reaction generation are not affected. Under the lower $H_2S$ concentration condition, the poisoning rate is much higher than that of CO because of its different adsorption intensity. It can be possible that the result of this study can be used for enacting regulation as a baseline data.

• Journal of Nutrition and Health
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• 제44권6호
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• pp.488-497
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• 2011

Oxygen is necessary to sustain life, yet cellular oxygen metabolism creates destructive elements called free radicals. Free radicals are chemically unbalanced and carrying free electrons that can damage molecules, potentially damaging the cell itself. For this reason, many antioxidant products, including supplements and functional foods, are being developed. In particular, natural products are rich sources of pharmacologically active compounds. The purpose of this study was to investigate the antioxidant effects of target biomaterials in Korean traditional spices such as diallyl sulfide (DAS), capsaicin (CAP), and gingerol (GGR), and to investigate the response of the antioxidant defense system to oxidative stress by hydrogen peroxide ($H_2O_2$) compared to sulforaphane (SFN) in HepG2 cells. After the analysis of the cell viability using Cell Counting kit-8 (CCK-8) assay, we determined that the optimum levels were $200{\mu}M$ DAS, $25{\mu}M$ CAP, $50{\mu}M$ GGR, and $12.5{\mu}M$ SFN. Antioxidant enzymes were measured and protein expression was detected by Western blotting. All treatments showed a significant decrease in antioxidant enzyme activity such as superoxide dismutase, catalse, and glutathione peroxidase in HepG2 cells. Additionally, DAS, CAP, GGR and SFN increased the antioxidant system-related transcription factor Nrf2 which was found to be regulated by the activation of MAPK-JNK in this study. In conclusion, these results indicate the protective effects of DAS CAP, GGR, and SFN against $H_2O_2$-induced oxidative stress.

• 한국가스학회지
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• 제4권4호
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• pp.1-5
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• 2000

[ $H_2S$ ]를 포함하는 액화천연가스(Liquified Natural Gas)의 기-액 조성을 noncubic 형태인 Modified-Benedict-Web-Robin EOS로 예측하였고, 그 결과를 대표적 cubic형태의 Peng-Robinson, Soave-Redlich-Kwong EOS로 예측한 기-액 조성과 비교 검토하였다.

• 대한환경공학회지
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• 제27권6호
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• pp.657-662
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• 2005

황화철은 자연 퇴적토와 공극수에서 생물학적 과정이나 무생물학적 과정에 의해서 상당량 생성된다. 본 연구에서는 6가 크롬과 황화철로부터 용해되어 나온 이가 철과 6가 크롬의 반응에 관하여 알아보기 위해 6가 크롬의 초기농도를 다르게 하여 pH 4와 8에서 수용액상과 고체상으로 나누어 실험을 수행하였다. 또한 철산화물인 ${\alpha}-Fe_2O_3$, ${\alpha}-FeOOH$, $Fe_3O_4$와 0가 철을 이용하여 황화철에 의한 6가 크롬의 제거효율을 비교하였다. 6가 크롬의 제거율은 pH 4일 때가 pH 8일 때 높았으며 이는 낮은 pH에서 황화철로부터 용해되어 나온 이가 철의 양의 pH 4에서 더 많기 때문인 것으로 판단된다. 투과전자 현미경(Transmission Electric Microscopy)을 이용한 황화철의 표면 분석을 통하여 고체 표면에 형성된 침전물을 확인하였다. 이는 황화철에 의한 6가 크롬의 환원 작용에 의하여 iron(oxyhyoxide) 침전이 형성된 것으로 판단된다. 황화철은 철 산화물 및 영가 철에 비하여 그 제거능이 월등하며 이는 이가 철과 함께 황화물의 상호작용인 것으로 사료된다.

• Journal of Biosystems Engineering
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• 제39권2호
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• pp.76-86
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• 2014

Purpose: The objective of this study was to measure emissions of gases (ammonia ($NH_3$), hydrogen sulfide ($H_2S$) and carbon dioxide ($CO_2$)), volatile organic compounds (VOC) and odor from two shallow pit pig nursery rooms. Gas and odor reduction practices for swine operations based on the literature were also discussed. Methods: This study was conducted for 60 days at a commercial swine nursery facility which consisted of four identical rooms with mechanical ventilations. Two rooms (room 1 (R1) and room 2 (R2)) with different pig numbers and ventilation rates were used in this study. The pig manure from both the R1 and R2 were characterized. Indoor/outdoor temperatures, ventilation rates/duration, $NH_3$, $H_2S$, $CO_2$, and VOC concentrations of the ventilation air were measured periodically (3-5 times/week). Odor concentrations of the ventilations were measured two times on two days. Three different types of gas and odor reduction practices (diet control, chemical method, and biological method) were discussed in this study. Results: The volatile solids to total solids ratio (VS/TS) and crude protein (CP) value of pig manure indicated the pig manure had high potential for gas and odor emissions. The $NH_3$, $H_2S$, $CO_2$ and VOC concentrations were measured in the ranges of 1.0-13.3, 0.1-5.7, 1600-3000 and 0.0-1.83 ppm, respectively. The $NH_3$ concentrations were found significantly higher than $H_2S$ concentrations for both rooms. The odor concentrations were measured in the range of $2853-4432OU_E/m^3$. There was significant difference in odor concentrations between the two rooms which was due to difference in pig numbers and ventilation duration. The literature studies showed that simultaneous use of dietary control and biofiltration practices will be more effective and environmentally friendly for gas and odor reductions from pig barns. Conclusions: The gas and odor concentrations measured in the ventilation air from the pig rooms indicate an acute need for using gas and odor mitigation technologies. Adopting diet control and biofiltration practices simultaneously could be the best option for mitigating gas and odor emissions from pig barns.