• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.3-6
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• 2004

Industrial gas separation by membranes began in 1980 with the introduction of hollow-fiber polysulfone membrane systems by Permea, at that time a division of Monsanto. This first application was the recovery of hydrogen from ammonia reactor purge gas and was soon followed by the generation of nitrogen from air. Today, membrane gas separation ranks second behind cryogenic distillation in terms of nitrogen production, and this application has drawn the industrial gas companies into the membrane field.(omitted)

• 한국전기화학회:학술대회논문집
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• 2004.06a
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• pp.129-134
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• 2004

문헌 연구를 통해 최적의 수소저장물질의서 수소저장 효율, 물질의 안정성 및 경제성이 우수한 나트륨붕소수소화물($NaBH_4$, sodium borohydride)을 선정하여, 소형연료전지용 수소저장시스템에 대한 다양한 특성을 조사하였다. $NaBH_4$의 기초 물성 조사를 위해 수소 발생 능력, 용해도, 수소 비발생 등의 실험을 수행하였으며 다양한 촉매의 특성비교는 물론 수소저장시스템의 설계시 핵심적으로 고려할 수 있는 Key factor의 특성을 파악하였다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.8 no.6
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• pp.1566-1571
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• 2007

Oligodeoxyribonucleotide bearing the di-acetylenic linkage has been prepared. Staring from 5-Iodo-2'-deoxyuridine(1), a four-step sequence, consisting of the Pd(0)-catalyzed Heck-type C-C coupling with acetylenic group, protection of 5'-hydroxy group, generation of acetylenic hydrogen, and Glaser oxidative coupling reaction leads to the dimeric oligodeoxyribonucleotide(5).

• Proceedings of the KIEE Conference
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• 2005.07a
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• pp.223-225
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• 2005

This paper will be introduce a new paradigm and prospects for energy supply system in near future which produces electric and district heat cogeneration with dispersed power grid with small nuclear power units. Recently, in nuclear field, a lot of effort has been done in nuclear major countries to develop small and medium reactor for enhancement of nuclear peaceful use as like in district heating, electric power generation, seawater desalination or hydrogen generation. This paper presents a new way and prospects for power source in distribution system by using the distributed & remote cogeneration system using small reactor.

• Journal of Industrial Technology
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• v.25 no.A
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• pp.141-149
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• 2005

We investigated numerically the evolutions of several chemical species which are important for film growth and particle generation in the pulsed $SiH_4$ plasmas. During the plasma-on, the $SiH_x$ concentration increases with time mainly by the generation reaction from $SiH_4$, but, during the plasma-off, decreases because of the hydrogen adsorption reaction. During the plasma-on, the concentrations of negative ions increase with time by the polymerization reactions of negative ions and those become almost zero in the sheath regions because of the electrostatic repulsion. During the plasma-off, the concentrations of negative ions decrease with time by the neutralization reactions with positive ions and some negative ions can diffuse toward the sheath regions because there is no electric field inside the reactor. The polymerized negative ions of higher mass can be reduced successfully by using the pulsed plasma process.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.3125-3130
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• 2008

Coal is one of the most abundant and cheapest energy sources in the earth, but its typical combustion product, $CO_2$, is related with serious recent environmental issues such as global warming. The Integrated Coal Gasification Combined Cycle (IGCC) with $CO_2$ sequestration is one of the most promising options to produce electricity using a relatively cheap fuel (coal) with minimum impact on environment. In IGCC power generation systems, some chemical reactions are required to gasify coal to produce syngases such as $H_2$ and CO, which would be burnt in the combustor to produce heat for power generation, with a penalty of additional energy consumption. In this paper, several chemical reactions for the gasification of coal are considered and their characteristics are investigated.

• Journal of the Optical Society of Korea
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• v.17 no.1
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• pp.10-15
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• 2013

Adsorption behavior of counterions under a Langmuir monolayer was investigated by sum-frequency generation (SFG) spectroscopy. By comparing SFG spectra of arachidic acid (AA) Langmuir monolayer/water interface with and without added salt, it was found that the simple trivalent cation $La^{3+}$ adsorbed on AA monolayer only when the carboxylic headgroups are charged (deprotonated), implying that counterion adsorption is induced by Coulomb interaction. On the other hand, metal hydroxide complex $Fe(OH)_3$ adsorbed even on a charge-neutral AA monolayer, indicating that the adsorption of iron hydroxide is due to chemical interaction such as covalent or hydrogen bonding to the headgroup of the molecules at the monolayer.

• Transactions of the Korean hydrogen and new energy society
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• v.25 no.5
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• pp.533-540
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• 2014

The remanufacturing industry for automotive parts is a major issue which affects the environment protection and CO2 reduction throughout the world. Beside this, remanufacturing technologies of worn-out diesel engines have been developing to make as close to new as possible. In this study, the characteristics of the engine-power output and exhaust emissions of remanufactured diesel engine by hydrogen enrichment are evaluated by measuring the engine and vehicle test. Moreover, with worn-out diesel engine and first generation common-rail engine, we compared by testing their characteristics, resulting in the restoration of engine-power output more than 93%, as well as marvelously reduces the THC and NOx emission. At a guess, high pressure injection of diesel increases fuel atomization characteristics with excellence combustion efficiency, resulting in reduction of THC emission. Also, rapid cooling of EGR decreases combustion temperature, resulting in reduction of NOx emission. Consequently, these remanufacturing for diesel engine enables worn-out diesel engine to have restoration to the original state. Simultaneously achieved 2 goals called that CO2 emission reduction and protection of environment by remanufacturing engine.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.4
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• pp.300-308
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• 2009

In a pursuit of the development of alternative mobile power sources with a high energy density, a planar and air-breathing PEMFCs with a new type of hydrogen cartridge which uses onsite $H_2$ generated from sodium borohydride ($NaBH_4$) hydrolysis have been investigated for use in advanced power systems. Two types of $H_2$ generation through $NaBH_4$ hydrolysis are available: (1) using organic acids such as sulphuric acid, malic acid, and sodium hydrogen carbonate in aqueous solution with solid $NaBH_4$ and (2) using solid selected catalysts such as Pt, Ru, CoB into the stabilized alkaline $NaBH_4$ solution. It might therefore be relevant at this stage to evaluate the relative competitiveness of the two methods mentioned above. The effects of flow rate of stabilized $NaBH_4$ solution, MEA (Membrane Electrode Assembly) improvement, and type and flow control of the catalytic acidic solution have been studied and the cell performances of the planar, air-breathing PEMFCs using $NaBH_4$ has been measured from aspects of power density, fuel efficiency, energy density, and fast response of cell. In our experiments, planar, air-breathing PEMFCs using $NaBH_4$ achieved to maximum power density of 128mW/$cm^2$ at 0.7V and energy efficiency of 46% and has many advantages such as low operating temperature, sustained operation at a high power density, compactness, the potential for low cost and volume, long stack life, fast star-up and suitability for discontinuous operation.

• Advances in Energy Research
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• v.2 no.1
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• pp.33-45
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• 2014

Photocatalytic hydrogen generation by water splitting ($H_2O_{(1)}{\rightarrow}H_2_{(g)}+1/2O_2_{(g)}$) has been studied on photocatalysts based on Zn, Cd, Fe and Cu, synthesized by coprecipitation. Iron and copper nanoparticles were incorporated as cocatalysts to enhance the photocatalytic activity of the ZnCd solid solution. The effect of the different synthesis parameters (temperature, elemental atomic ratios, amount of Cu and Fe incorporated in the catalyst and calcination temperature) on the photocatalytic production of hydrogen has been studied in order to determine the best experimental synthesis conditions. The catalysts have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and BET. The experiments of photocatalytic water splitting were performed in aqueous solution of the photocatalysts previously dispersed in a soft ultrasound bath. The photocatalysts were irradiated under different lights ranging from 220 to 700 nm. The photocatalytic activity was found to be clearly dependent on the specific area of the photocatalyst.