• Journal of Digital Convergence
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• v.14 no.9
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• pp.281-286
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• 2016

In this paper, we optimized the structure of hydrogen water generator and assessed by developing a generator with dissolved hydrogen amount(1,000~1,200 ppb) of world-class level. Evaluation is divided into four types, such as dissolved hydrogen amount, pH, maximum pressure, redox potential, and it was evaluated for each of the targets. It was performed through the experiment of four in all five times and all of them show superiority results appearing in the target range. In addition, the assessment got 25/30 functionality, 17/20 maintainability, 26/30 usability, and 19/20 efficiency. In particular, we proved the validity of this study in high efficiency. We developed this hydrogen water generator system as possible to be substitution of water purifier.

• Korean Chemical Engineering Research
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• v.43 no.3
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• pp.331-343
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• 2005

Development of hydrogen station system is an important technology to commercialize fuel cells and fuel cell powered vehicles. Generally, hydrogen station consists of hydrogen production process including desulfurizer, reformer, water gas shift (WGS) reactor and pressure swing adsorption (PSA) apparatus, and post-treatment process including compressor, storage and distributer. In this review, we investigate the R&D trends and prospects of hydrogen station in domestic and foreign countries for opening the hydrogen economy society. Indeed, the reforming of fossil fuels for hydrogen production will be essential technology until the ultimate process that may be water hydrolysis using renewable energy source such as solar energy, wind force etc, will be commercialized in the future. Hence, we also review the research trends on unit technologies such as the desulfurization, reforming reaction of fossil fuels, water gas shift reaction and hydrogen separation for hydrogen station applications.

• Corrosion Science and Technology
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• v.21 no.6
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• pp.466-475
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• 2022

Surface oxides and intergranular (IG) oxidation phenomena in Alloy 600 depending on hydrogen concentration were characterized to obtain clear insight into the primary water stress corrosion cracking (PWSCC) behavior upon exposure to pressurized water reactor primary water. When hydrogen concentration was between 5 and 30 cm³ H₂/kg H₂O, NiFe₂O₄ and NiO type oxides were found on the surface. NiO type oxides were found inside the oxidized grain boundary when hydrogen concentration was 5 cm³ H₂/kg H₂O. However, only NiFe₂O₄ spinel on the surface and Ni enrichment were observed when hydrogen concentration was 30 cm³ H₂/kg H₂O. These results indicate that the oxidation/reduction reaction of Ni in Alloy 600 depending on hydrogen concentration can considerably affect surface oxidation behavior. It appears that the formation of NiO type oxides in a Ni oxidation state and Ni enrichment in a Ni reduction (or metallic) state are common in primary water. It is believed that the above different oxidation/reduction reactions of Ni in Alloy 600 depending on hydrogen concentration can also significantly affect the resistance to PWSCC of Alloy 600.

• Journal of the Korean Institute of Gas
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• v.28 no.2
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• pp.17-23
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• 2024

As interest in sustainable and eco-friendly energy increases due to various problems in the carbon economy, a hydrogen economy that utilizes hydrogen as a main energy source is emerging. Among the methods of producing hydrogen, the water electrolysis method based on renewable energy produces environmentally friendly green hydrogen because it produces hydrogen from water. The water electrolysis facility currently under development produces hydrogen by receiving electricity directly from renewable energy and uses KOH(potassium hydroxide) as an electrolyte. In this study, HAZOP(Hazard and Operability Study), a qualitative risk assessment, was conducted on alkaline water electrolysis facilities to find problems and risk factors in the design and operation of water electrolysis facilities. Risks related to oxygen and KOH, an electrolyte, were identified as major risks, and it is believed that the safety of facilities and workers can be secured based on emergency action plans and safe operation procedures.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.495-498
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• 2008

Photocatalytic water splitting into $H_2$ and $O_2$ using semiconductors has received much attention, especially for its potential application to direct production of $H_2$ for clean energy from water utilizing solar light energy. Since the report of Fujishima and Honda on the water splitting by photoelectrochemical cells, numerous different semiconducting materials have been used as photocatalysts for hydrogen generation from water. Among them, platinized titania significantly accelerates hydrogen production from water. For geometrical improvement of $TiO_2$ particle, porous $TiO_2$ structure was proposed and studied such as nanofiber, nanorod and nototubes. This research focuses on finding out the optimum temperature and electrolyte to produce $H_2$ by solar water splitting.

• Journal of Surface Science and Engineering
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• v.55 no.3
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• pp.180-186
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• 2022

The production of hydrogen via water electrolysis (i.e., green hydrogen) using renewable energy is key to the development of a sustainable society. However, most current electrocatalysts are based on expensive precious metals and require the use of highly purified water in the electrolyte. We demonstrated the preparation of a non-precious metal catalyst based on CuCo₂O₄ (CCO) via simple electrodeposition. Further, an optimization process for electrodeposition potential, solution concentration and electrodeposition method was develop for a catalyst-substrate integrated electrode, which indicated the highly electrocatalytic performance of the material in electrochemical tests and when applied to an anion exchange membrane water electrolyzer.

• The Korea Journal of Herbology
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• v.26 no.1
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• pp.53-58
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• 2011

Objectives : The purpose of this study is to investigate effects of Scutellariae Radix Water Extract on hydrogen peroxide production in RAW 264.7 mouse macrophages. Methods : Scutellariae Radix produced from South Korea (SK) and Scutellariae Radix produced from China (SC) were extracted by hot water. Effects of SK and SC on hydrogen peroxide production in RAW 264.7 were measured by dihydrorhodamine 123 assay after 2, 4, 20, 24, 28, 44, and 48 h incubation at the concentrations of 10, 25, 50, and 100 ug/mL. Results : SK significantly increase hydrogen peroxide production in RAW 264.7 cells for 2, 4, 20, 24, 28, 44, and 48 h incubation at the concentrations of 10, 25, 50, and 100 ug/mL (P < 0.05). SC also significantly increase hydrogen peroxide production in RAW 264.7 cells for 4, 20, 24, 28, and 48 h incubation at the concentrations of 10, 25, 50, and 100 ug/mL (P < 0.05). For 2 h incubation, SC significantly increase hydrogen peroxide production in RAW 264.7 cells at the concentrations of 10, 25, and 100 ug/mL (P < 0.05). For 44 h incubation, SC significantly increase hydrogen peroxide production in RAW 264.7 cells at the concentrations of 10, 25, and 50 ug/mL (P < 0.05). Conclusions : These results suggest that Scutellariae Radix has the immune - enhancing property related with its increasement of hydrogen peroxide production in macrophages.

• Journal of Hydrogen and New Energy
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• v.27 no.2
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• pp.155-162
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• 2016

A proton exchange membrane fuel cell (PEMFC) produces only water at cathode by an electrochemical reaction between hydrogen and oxygen. The generated water is transported across the membrane from the cathode to the anode. The transported water collected in water-trap and drained to the cathode within the humidifier outlet. If the condensate water is not being drained at the appropriate time, condensate water in the anode can cause the performance degradation or fuel efficiency degradation of fuel cell by the anode flooding or unnecessary hydrogen discharge. In this study, we proposed an optimization method of condensate water drain logic for the water drain performance and the water drain algorithm as considered the condensate water generating speed prep emergency case. In conclusion, we developed the water management strategy of fuel processing system (FPS) as securing fuel efficiency and operating stability.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.167.1-167.1
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• 2016

The interaction between adsorbed water and hydrogen on metallic surfaces is important for fundamental understanding of heterogeneous catalysis and electrode surface reactions in acidic environment. Here, we explore a long-standing question of whether hydronium ion can exist or not on a Pt surface coadsorbed with atomic hydrogen and water. Studies based on mass spectrometry and infrared spectroscopy show clear evidence that hydrogen atoms are converted into hydrated protons on a Pt(111) surface. The preferential structures of hydrated protons are identified as multiply hydrated $H_5O_2{^+}$ and $H_7O_3{^+}$ species rather than as hydronium ions. The multiply hydrated protons may be regarded as two dimensional zundel ($H_5O_2{^+}$) and Eigen cation ($H_7O_3{^+}$) in water-metal interface. These surface-bound hydrated protons may be key surface intermediates of the electrochemical interconversion between adsorbed hydrogen atoms and solvated protons.

• Journal of Hydrogen and New Energy
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• v.8 no.4
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• pp.155-160
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• 1997

Generation of hydrogen and oxygen gas from water is mostly accomplished by electrolysis. In this report, a scheme is presented regarding the gas generation based on plasmolysis. Unlike electrolysis water dissociation by electrical discharge (plasmolysis) requires a high voltage to cause either electron emission or electron capture, and subsequent ionization of involved molecular species. When electrical discharge is initiated between electrodes separated by water-vapor interface, a very large electric field(~100kV/cm) is developed at the tip of the electrode placed in the vapor phase. It is found that the efficiency of plasmolysis depends on the polarity of the electrode placed in the vapor phase. Also presented is the scheme of hydrogen and oxygen generation by such electrical discharge.