• 한국수소및신에너지학회논문집
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• 제15권4호
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• pp.301-308
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• 2004

The methane reforming with $CO_2$ and steam for manufacture of synthesis gas over $Ni/ZrO_2$ catalyst was investigated. Mixed reforming carried out $CO_2$ dry reforming with $O_2$ and steam for development of DME process in pilot plant. To improve a catalyst deactivation by coke formation, the mixed reforming added carbon dioxide and steam as a oxidizer of the methane reforming was suggested. The result of experiments over commercial catalyst in $CO_2$ dry reforming has shown that the catalyst activity decrease rapidly after 20 hours. In case of $NiO-MgO/Al_2O_3$ catalyst, the deactivation of 20 percent after 30 hours was occurred. The activity of Ni/C catalyst still was not decreased dramatically after 100 hours. The effect of $H_2$ reforming with steam over $Ni/CO_2$ catalyst obtained the optimal conversion of methane and carbon dioxide, and could be produced synthesis gas at ratio of $H_2/CO$ under 1.5.

• 한국가스학회지
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• 제5권1호
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• pp.15-20
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• 2001

저온 마이크로웨이브 플라즈마와 촉매반응에 의한 메탄올 활성화하여 C2+ 화합물과 수소로 전환하는 반응을 고찰하였다. 금속 촉매인 Fe, Ni과 귀금속 촉매인 Pt, Pd 계열의 촉매로 본 실험을 수행하였다 메탄의 유속이 $20ml\;min^{-1}$일때 플라즈마의 출력이 증가할수록 C2+ 생성물은 29에서 $42\%$로 증가하였으며 동시에 메탄의 커플링 반응에서 발생하는 수소는 0.6에서 0.65 몰분율을 나타내었다. 촉매는 플라즈마 영역 후단에 위치하였을 때, C2+ 생성물이 일정한 수율을 나타내는 반면 에틸렌과 아세틸렌의 선택도는 향상되었다. 플라즈마 반응후 ECR 전기장과 Pd-Ni 이원촉매를 위치했을 때 최고의 C2+ 수율은 $64\%$로 관찰되었다.

• 한국가스학회지
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• 제13권1호
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• pp.45-51
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• 2009

본 논문은 국내에 건설된 충전소를 분석 검토하여 수소충전소에 대한 안전성 평가를 실시함으로써 수소충전 소의 안전성에 대한 확인과 충전소 설치 시 필요한 기준마련에 기초자료를 제공하는 것이 궁극적인 목표이다. 안전성 평가 방법으로 FMEA (Failure Mode and Effect Analysis)를 사용하였고, 충전소를 크게 4개의 공정(제조, 압축, 저장, 충전)으로 분류하였다. 또한 각각의 발견된 위험요소에 S (severity), O (occurrence), D (detection)의 점수를 부여하여 이 세 요소의 곱의 값인 RPN (Risk Priority Number)의 수치를 이용하여 위험의 우선순위를 정하고, 이를 바탕으로 시나리오를 생성하였다. 생성한 시나리오를 기반으로 사고피해영향평가 결과 주요한 사고 유형으로 jet fire와 폭발이 나타났고, PSA (pressure swing adsorption) 공정 feed line에서의 누출의 경우 원료물질에 따라 CO가스의 농도가 상이할 수도 있으나, CO가스중독 위험성을 함께 예측되었다.

• 동력기계공학회지
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• 제20권5호
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• pp.86-91
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• 2016

This paper is concerned chiefly with the method of porous foam manufacture using basalt stone powder sludge. The hydrogen peroxide($H_2O_2$) of bloating agent has lots of problems to manufacture porous lightweight aggregate due to fast reaction rate with cement or calcium hydroxide($Ca(OH)_2$). The $H_2O_2$ injecting method using nozzle for manufacturing porous lightweight aggregate is proposed, in this study. This method is to inject $H_2O_2$ at the pressure of 10 MPa on upper side of slurry mixing materials such as stone powder sludge and quick-lime(CaO) by injector. The specimen was dried in furnace at $100^{\circ}C$ for 1 hour and cured at ambient temperature for 30 days. We analyzed the characteristics including specific gravity and water absorption. The experiments were found that the porous foam has low specific gravity, high water absorption and uniform distribution of porous more than manufactured foam by general bloating methods.

• Journal of Welding and Joining
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• 제30권6호
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• pp.10-14
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• 2012

Recently the low alloy steel plate made with manganese-molybdenum is used widely in steam drum and separator of the new coal-fired power plant boiler. This material is suitable for the vapor storage of high pressure and high temperature. The high temperature creep strength of Mn-Mo alloy is higher than the carbon plate(SA516) that used in the subcritical pressure boiler. It reduces the thickness of the pressure vessel and makes the lightweight possible. Recently in the power plant boiler operation and production process, the damage has happened frequently in the heat affected zone and base material according to the hydrogen crack and delayed crack. This paper describes the research result about the damage case experienced in the boiler steam drum production process and present the optimum manufacture method for the similar damage prevention of recurrence.

• 한국수소및신에너지학회논문집
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• 제28권4호
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• pp.426-432
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• 2017

Hydrothermal carbonization (HTC) is an effective and environment friendly technique; it possesses extensive potential towards producing high-energy density solid fuels. it is a carbonization method of thermochemical process at a relatively low temperature ($180-250^{\circ}C$). It is reacted by water containing raw material. However, the production and quality of solid fuels from HTC depends upon several parameters; temperature, residence time, and pressure. This study investigates the influence of operating parameters on solid fuel production during HTC. Especially, when food waste was reacted for 2 hours, 4 hours, and 8 hours at $200^{\circ}C$ and 2.0-2.5 MPa, Data including heating value, proximate analysis and water content was consequently collected and analyzed. It was found that reaction temperature, residence time are the primary factors that influence the HTC process.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.209-212
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• 2001

Aircraft industry is developed very fast so titanium scrap was generated to manufacture. Titanium scrap was wasted and used to deoxidize cast iron so we are study recycling of it. In this research were studied that metal hydride of reacted in hydrogen chamber of AMS4900, 4901, return scrap titanium alloy and sponge titanium granule. The temperature of hydrogenation was 40$0^{\circ}C$ in the case of pure sponge titanium but return scrap titanium alloy were step reaction temperature at 40$0^{\circ}C$ and 50$0^{\circ}C$, and after the hydride of titanium alloy were crushed by ball mill for 5h. Titanium hydride contains to 4wt.% of hydrogen theoretically as theory. It was determined by heating and cooling curve in reaction chamber. The result of XRD was titanium hydride peak only that it was similar to pure titanium. Titanium hydride Powder particle size was about 45${\mu}{\textrm}{m}$, and recovery ratio was 95w% compared with scrap weight for a aluminum foam agent.

• Food Science and Biotechnology
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• 제16권6호
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• pp.1041-1045
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• 2007

Heated onion juice was partitioned using the solvents hexane, chloroform, ethyl acetate, and butanol. The ethyl acetate fraction showed the strongest scavenging effect on the ABTS radical. The antioxidant activities of the ethyl acetate fraction from raw and heated onion (120, 130, and $140^{\circ}C$) were evaluated using radical scavenging assays. Radical and nitrite scavenging activities were higher in heated onion than raw onion, and the higher the temperature of heat treatment, the greater the radical and nitrite scavenging activities. Heated onion ($140^{\circ}C$, 2 hr) was more effective than raw onion, having higher DPPH radical scavenging (5.7-fold), hydroxyl radical scavenging (6.4-fold), superoxide radical scavenging (2.3-fold), hydrogen peroxide scavenging (11.8-fold), and nitrite scavenging (4.3-fold) activities. Onion increased its physiologically active materials after heating, and in this regard, heated onion can be used as biological material for the manufacture of health foods and supplements.

• 한국수소및신에너지학회논문집
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• 제28권5호
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• pp.502-511
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• 2017

Design, manufacture and operate the 700W Solid oxide fuel cell system suitable for housing. Except for BOP not produced domestically, most of the domestic BOPs were applied as much as possible. Finally, the system size was 350 liter. System performance was electric efficiency 44.64%, thermal efficiency 40.99%, total efficiency 85.62% at certificate authority. The system was operated for 4,500 hours, this operation time include automatically system on/off, E-stop for emergency stop, load trip for blackout and inverter error. There were that the system on/off were 26 times. System performance remains intact after system on/off.

• 한국수소및신에너지학회논문집
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• 제25권4호
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• pp.364-377
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• 2014

The performances of a coupled reactor in which a steam reformer and a catalytic combustor were mounted simultaneously had been investigated and compared. The combustible offgas exhausted from the anode of SOFC and MCFC were utilized as heat sources for the endothermic steam methane reforming. The catalytic combustion was used in order to burn the combustible offgas. Thermal energy released by the catalytic combustion is directly transferred to the reformer surrounding the combustor. The various operational conditions such as fuel utilization rate, steam to carbon ratio, amount of catalysts, fuel cell loads were changed. And operating variables were comprehensively identified by sensitivity analysis. The fundamental results from this experimental study show the potential abilities of the coupled reactor. Therefore the results will be of help to design and manufacture the more better coupled reactor in the future.