• Journal of the Korean Institute of Gas
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• v.24 no.6
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• pp.83-90
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• 2020

This study conducted a risk assessment using the HyKoRAM program created by international joint research. Risk assessment was conducted based on accident scenarios and worst-case scenarios that could occur in the facility, reflecting design specifications of major facilities and components such as compressors, storage tanks, and hydrogen pipes in the hydrogen charging station, and environmental conditions around the demonstration complex. By identifying potential risks of hydrogen charging stations, we are going to derive the worst leakage, fire, explosion, and accident scenarios that can occur in hydrogen storage tanks, treatment facilities, storage facilities, and analyze the possibility of accidents and the effects of damage on human bodies and surrounding facilities to review safety.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.238-242
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• 2008

In this study, hydrogen sulfide ($H_2S$) production was examined during beer fermentation using two ale and two lager yeast strains. In the lager yeast fermentation, a large amount of $H_2S$ was produced in the early fermentation stages when the yeast were actively fermenting wort, indicating a positive relationship between the level of H2S production and the yeast growth rate during fermentation. The ale yeasts produced much lower levels of H2S than the lager yeasts. In the lager fermentation, a higher fermentation temperature shortened the fermentation period, but much higher levels of $H_2S$ were produced at higher temperatures. American pilsner lager yeast fermenting at $15^{\circ}C$ produced a relatively high level of $H_2S$ at the end of fermentation, which would require a longer aging time to remove this malodorous volatile sulfur compound. Not including the English ale strain, which produced a higher level of H2S at lower temperatures, the ale yeast produced lower levels of $H_2S$ at lower temperatures, suggesting that each strain has an optimum fermentation temperature for H2S production.

• Journal of the KSME
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• v.51 no.11
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• pp.42-44
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• 2011

이 글에서는 철강재료의 생산공정 및 사용 중 수소취화에 의해 발생하는 현상과 방지대책에 대하여 소개하고자 한다.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05b
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• pp.390-395
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• 1997

국내 원전연료 생산시설에서 발생되는 페지르칼로이를 이용하여 수소의 흡수ㆍ저장 가능성을 확인하였으며 $600^{\circ}C$에서 수소원자대 금속원자의 비율이 약 2.0으로 되는 것을 측정하였다. 지르칼로이의 수소화반응을 위해서는 100$0^{\circ}C$ 이상에서, 금속의 활성화 과정에 의한 금속 표면의 oxide film의 제거가 필요한 것으로 나타났으며 수소화반응은 15분 이내에 이루어지는 것으로 관찰되었다.

• Microbiology and Biotechnology Letters
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• v.14 no.5
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• pp.385-389
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• 1986

Both hydrogenase and nitrogenase were found to be involved in hydrogen evolution independently in Rhodopseudomonas sp. KCTC 1437. The hydrogen formation in this bacterium was independent on light illumination and presence of N $H_4^{+}$ After establishment of conditions to measure the amount of hydrogen evolved by each of the enzymes in vivo, the several factors affecting on the hydrogen evolution, e.g. presence of gases ( $C_2$ $H_2$, $H_2$, $O_2$ or $N_2$), C/N ratio, were investigated, Hydrogenase was less inhibited than nitrogenase under $O_2$ and was active independent on the presence of $N_2$ or $C_2$ $H_2$ which were the strong inhibitor of nitrogenase. Besides, the hydrogenase activity was increased after incubation with $H_2$. And it was verified that this bacterium consume hydrogen and photoreduce $CO_2$ by hydrogenase. From above results, it is concluded that hydrogenase in Rhodopseudomonas sp. KCTC 1437 can produce hydrogen under more favorable condition that nitrogenase.e.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.506-510
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• 2009

The effects of various organic wastes on anaerobic fermentative hydrogen production were studied using enriched mixed microflora in batch tests. Rotten fruit, corn powder and organic wastewater enriched with sulfate (up to 1,000 mg/L) were used for experiments. Maximum hydrogen production (547.1 mL) was observed from rotten apple with initial substrate concentration of 132.2 g COD/L. The experimental result on sulfate enriched organic wastewater indicated that hydrogen production is not adversely influenced by relatively high sulfate concentration. Residual sulfate content remained at 96-98 % after 75 hours of reaction, which showed that no major sulfate reduction was occurred at pH 5.3-5.5 in the reactor. The volatile fatty acid (VFA) fractions produced during the reaction was in the order of butyrate > acetate > propionate in all experiments. The results of this study would be useful for controlling the conditions on fermentative hydrogen production using different feedstocks.

• Journal of the Korean Institute of Gas
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• v.27 no.1
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• pp.13-22
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• 2023

As an alternative to environmental pollution generated from fossil fuels currently in use, research is being actively conducted to use hydrogen that does not cause air pollution. As fire and explosion accidents caused by hydrogen leakage have occurred until recently, research on safety is needed to commercialize hydrogen on ships, which are special environments. In this study, a seasonal alternative scenario for each season and the worst scenario were assumed in the event of a leakage accident while a hydrogen fuel cell propulsion ship equipped with a hydrogen storage tank was navigating at JangSaengPo port in Ulsan. In order to consider environmental variables, the damage impact range was derived through ALOHA and probit analysis based on the annual average weather data for 2021 by the Korea Meteorological Administration and on geographic information data from the National Statistical Office. Radiation showed a wider damage range than that of Overpressure and Flame in both the alternative and worst-case scenarios, and as a result of probit analysis, a fatality rate of 99% was confirmed in all areas.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05c
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• pp.311-316
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• 1996

제어봉이탈사고시의 핵연료봉 거동을 연구로에서의 반응도사고 모사실험 결과와 기존의 핵연료 손상기준을 비교하여 분석하였다. 반응도사고시 고연소도 핵연료의 손상은 주로 PCMI 기구로 발생하는데, 고연소도에서의 피복관의 부식 및 수소화 그리고 방사선조사에 의한 연성감소와 산화층 박리로 인한 수소화합물의 국부적인 집중화로 인한 피복관의 현저한 연성감소가 주요 원인이었다. 기존의 핵연료 손상 기준에서 DNB가 일어날때 핵연료 손상이 발생한다는 가정은 낮은 핵연료엔탈피에서 핵연료 손상이 일어나는 것과 동일함을 확인하였으며, 현재까지 발표된 실험자료와 핵연료손상기구의 분석을 통해 연소도에 따른 반응도사고시의 핵연료손상기준을 예비적으로 유도하였다. 핵연료손상은 낮은 연소도에는 DNB로 발생하고 고연소도에서는 PCMI로 발생할수 있기 때문에, 과도상태에서의 고연소도 핵연료의 건전성 유지를 위해서는 피복관 산화층의 박리로 인한 수소화합물의 집중화로 피복관의 연성이 감소되는 것을 방지할 필요가 있다.

• Journal of Welding and Joining
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• v.12 no.1
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• pp.7-15
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• 1994

알루미늄합금의 용도가 우주 항공기 부품에서 자동차, 선박, 건축 등 다양화되면서 이들 재료에 대한 용접기술 또한 산업현장의 주요한 과제로 등장하게 되었다. 알루미늄합금은 극히 활성이 높고, 열전도율이나 열팽창계수가 매우 큰 물리적 특성 및 액상과 고상간의 매우 큰 수소 용해도 차이 등의 특이한 성질을 가지고 있기 때문에 용접에 있어서는 기공이나 미세한 융합 불량이 발생하기 쉽고, 또 용접변형의 제어에도 세심한 배려를 요하는 등 우수한 용접부를 만들기 위해서 고려해야 할 문제를 가지고 있다. 특히 기공이 후판 알루미늄 합금 용접에 있어서 보수공사의 대부분을 차지하고 있으므로 기공 방지법을 확립하는 것은 매우 중요하다. 알루미늄 합금의 용접에 있어서 기공의 발생원인은 수소에 의한 것이라고 정립되어 있으나 그 방지법에 대해서는 많은 연구검토가 행해지고 있음에도 불구하고 수소의 공급경로가 매우 다양하고 복잡하기 때문에 아직 체계적으로 확립되어 있지 못한 실정이다. 본 해설에서는 후판 알루미늄 용접시 가장 큰 문제가 되는 기공의 발생 원인과 방지대책을 기 발표된 자료를 기초로 하여 요약 정리함으로써 앞으로 여러 생산현장에서의 알루미늄합금 용접 특히 MIG 용접 관련 문제점 해결에 도움이 되고자 한다.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.117-117
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• 2007