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Full Text: hydrogen water
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  • Kenji Takahara, Kouji Maekawa
    Journal of Asian Electric Vehicles
    2014 Volume 12 Issue 2 1687-1691
    Published: 2014
    Released: December 25, 2014
    JOURNALS FREE ACCESS
    The purpose of this study is to develop a microcompact fuel-cell vehicle equipped with a hydrogen generation system. Hydrogen is generated by the reaction between water and activated aluminum particles without carbon dioxide emission. The activated aluminum is made of aluminum cutting waste through activation treatments such as compression crushing and freezing dry. One gram of the activated aluminum particles can generate about 1.1 liters of pure hydrogen. The developed hydrogen generator is consists of a water tank, an electrical pump, a reaction container, a condensate return tank, sensors and a one-chip microcomputer. It generated about 1-4 [l/min] of hydrogen over one hour. A microcompact vehicle was manufactured experimentally based on a delta trike. The front wheel was driven by a brushless motor of 100 [W]. The developed hydrogen generator and a fuel-cell of 100 [W] were equipped on the microcompact vehicle. It was confirmed that the vehicle drive at about 11 [km/h] over 90 minutes.
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  • Kenji Takahara, Kouji Maekawa, Toshinori Kajiwara, Masao Watanabe
    Journal of Asian Electric Vehicles
    2008 Volume 6 Issue 2 1153-1157
    Published: 2008
    Released: May 15, 2009
    JOURNALS FREE ACCESS
    The purpose of this study is to describe the experiments of hydrogen generation from water molecules reacting with activated aluminum particles and the identification of its characteristics using an ARMA model on the assumption of the applications for a fuel-cell vehicle. Because 1 gram of the activated aluminum particles can generate about 1.1 liters of pure hydrogen, they have application possibility as the hydrogen resource of a fuel cell car. However, the details of hydrogen generation characteristics by this reaction are not well known. The reaction has non-linearity and time-varying due to the characteristics of the sample, the external environment and so on. Therefore, it is difficult to construct a mathematical model based on the physiochemical law of the reaction. Here, the dynamic characteristics of hydrogen generation are assumed to be described as a linear ARMA model using the reaction temperature and hydrogen generation. The parameters of ARMA model are identified by a constant trace adaptive algorithm using the measured data. The outputs of the ARMA model are well accorded with the measured data.
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  • Hiraku Tanimoto, Hiroyoshi Tanaka, Joichi Sugimura
    Tribology Online
    2011 Volume 6 Issue 7 291-296
    Published: September 15, 2011
    Released: September 15, 2011
    JOURNALS FREE ACCESS
    This paper describes an experimental study on permeation of hydrogen into bearing steel through fresh surface with thermal desorption spectroscopy. Sliding experiments using a lapping machine with and without lubricant were conducted to generate fresh surfaces. Desorption spectra were taken before and after sliding, and the surfaces were analyzed with X-ray photoelectron spectroscopy. It was found that oxide and/or hydroxide film was formed on the surface, whereby hydrogen was generated and diffused into the bulk steel. When heated, some of hydrogen in the steel reacted with the surface film to be desorbed as water, while some other hydrogen was desorbed in the form of hydrogen molecules. Hydrogen desorption spectra in combination with water desorption spectra thus provides information not only on hydrogen permeated but also on surface oxide/hydroxide film.
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  • K. Domen
    Abstract of annual meeting of the Surface Science of Japan
    2018 Volume 2018 2Bpi10
    Published: 2018
    Released: November 19, 2018
    CONFERENCE PROCEEDINGS FREE ACCESS
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  • Takeharu Kizaki, Yoshiki Mikami, Nao Kawabe, Hiroshi Matsuda, Rinsei Ikeda, Masahito Mochizuki
    QUARTERLY JOURNAL OF THE JAPAN WELDING SOCIETY
    2017 Volume 35 Issue 2 108s-111s
    Published: 2017
    Released: February 01, 2018
    JOURNALS FREE ACCESS
    Hydrogen related delayed fracture is a critical issue to be solved to enhance the application of high-strength steels. This hold true with the high strength steels and its welds used in automotive applications. The trend of the increase of the strength of steels used will continue, therefore, it is important to investigate the hydrogen related fracture of high-strength automotive steels. In this study, hydrogen diffusion and accumulation behavior in the high-strength steel welds has been investigated by numerical simulation. The residual stress distribution of the resistance spot welds was considered as the driving force of hydrogen diffusion. The hydrogen diffusion was simulated under residual stress field with different initial hydrogen distributions and boundary conditions. When the diffusible hydrogen distributed uniformly in the weld metal just after welding, hydrogen diffused rapidly after welding and retained slightly at the center of the weld metal. When the diffusible hydrogen was introduced through the surface of the welded joint, diffusible hydrogen accumulated in the area of high tensile stress. In addition, the rate of increase of the hydrogen concentration was dependent on the distance from the surface of the welded joint.
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  • Yanlin Chen, ChangYue Lee, JiaMing Zhao, Ting Hou, ZhiJing Lee, Xuefeng LYU
    The Proceedings of the International Conference on Nuclear Engineering (ICONE)
    2019 Volume 2019.27 1543
    Published: 2019
    Released: December 25, 2019
    CONFERENCE PROCEEDINGS RESTRICTED ACCESS
    With the development of small modular reactors, the hydrogen risk reducing technology cannot be ignored. Special safety facilities of small modular reactor (SMR) are investigated and studied, and a serious accident analysis program model for SMR is established. The combination of Pre-inerting and hydrogen recombination was used to control the hydrogen risk. The effectiveness of the hydrogen control system is analyzed by using the GASFLOW program. The results show that the volume fraction of hydrogen in the containment dome is higher than that in the other parts of the containment during the calculation. Because of the small size and tight internal structure, hydrogen accumulates in the narrow channel, which increases the hydrogen concentration in the local channel. Inerting reduces the concentration of oxygen in the containment and effectively controls the possibility of flame acceleration and blasting transition in high hydrogen concentration regions.
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  • Keitaro Horikawa, Hiroaki Okada, Hidetoshi Kobayashi, Wataru Urushihara
    MATERIALS TRANSACTIONS
    2009 Volume 50 Issue 9 2201-2206
    Published: September 01, 2009
    Released: August 25, 2009
    [Advance publication] Released: July 23, 2009
    JOURNALS FREE ACCESS
    Hydrogen permeation behavior in carbon steel exposed to gaseous hydrogen was visualized using a hydrogen microprint technique (HMT). Effects of hydrogen gas pressure and charging time on the hydrogen permeation were particularly examined. The amount of permeated hydrogen was dependent on the charging time during the exposure to gaseous hydrogen. It was found that silver particles, which represented the evolution site of hydrogen atoms, were distributed almost uniformly in the matrix after hydrogen gas charging. These particles were arranged at the periphery of the second phase particles such as Al2O3. Area density of the silver particles clearly increased when the time for hydrogen gas charging was increased. Preferential accumulation of silver particles around Al2O3 particles was clearly identified; however, no silver particles were observed directly on the Al2O3 particles. This indicated that hydrogen atoms were diffused not through the inside of the second phase particles but through the interface between the second phase particles and the matrix phase.
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  • WU Xiang, WANG Chang-Mao, LIU Shang-Bo, OUYANG Dong-Fang
    The Proceedings of the International Conference on Nuclear Engineering (ICONE)
    2019 Volume 2019.27 1091
    Published: 2019
    Released: December 25, 2019
    CONFERENCE PROCEEDINGS RESTRICTED ACCESS
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  • Yoshinori Shirasaki, Tatsuya Tsuneki, Tsutomu Seki, Isamu Yasuda, Takafumi Sato, Naotsugu Itoh
    JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
    2018 Volume 51 Issue 1 123-125
    Published: January 20, 2018
    Released: January 20, 2018
    JOURNALS RESTRICTED ACCESS

    Hydrogen permeable membranes composed of palladium-transition metal binary alloy were prepared. The palladium membrane alloyed with the transition metals of Group 3A that was able to dissolve more than 8 at% in palladium, silver and gold, showed higher hydrogen permeability compared to that of a pure palladium membrane. In particular, the hydrogen permeability of a palladium–holmium membrane was found to be the highest in this study, and two times higher than that of palladium–silver membrane.

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  • Narangoo Purevjav, Takuo Okuchi, Xiaoping Wang, Christina Hoffmann
    Abstracts for Annual Meeting of Japan Association of Mineralogical Sciences
    2017 Volume 2017 R2-11
    Published: 2017
    Released: January 16, 2020
    CONFERENCE PROCEEDINGS FREE ACCESS
    Ringwoodite is the most important water reservoir in the deep mantle. In order to understand the effect of water on its physical properties, it is essential to elucidate the position of hydrogen and its exchanging mechanism with the other cations in the ringwoodite crystal structure. Here we show our single crystal neutron diffraction results of hydrous ringwoodite, which was conducted for the first time on it for resolving its hydrogen position. We successfully demonstrated the hydrogen position and its occupancy in the ringwoodite crystal structure.
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  • Yuki YAMAGUCHI, Shunji IMAMURA, Keishi NISHIO, Kenjiro FUJIMOTO
    Journal of the Ceramic Society of Japan
    2016 Volume 124 Issue 6 629-633
    Published: June 01, 2016
    Released: June 01, 2016
    JOURNALS FREE ACCESS
    Platinum catalyst loaded tungsten oxide (Pt/WO3) is a promising candidate as a hydrogen gas sensor material, which can detect it through optical and electrical sensing. The sensor, which can detect the hydrogen gas stably in various environments, is strongly demanded. In this study, we prepared the Pt/WO3 thin film by the sol–gel method and evaluate the dependence of the hydrogen gas sensing property on measuring temperature and humidity. Hydrogen gas sensing property of Pt/WO3 thin film was evaluated by measuring the electrical conductivity with humid (0–100% of relative humidity) hydrogen gas exposure at various temperatures. The sensing property was declined in humid atmospheres because the water molecule adsorbing on the film surface disturbed the catalytic reaction between hydrogen and Pt surface. In addition, the catalytic combustion of hydrogen molecule on Pt was also disturbed by the adsorbed water. However, the heating at 60°C can remove the effect of water molecule and the film can detect hydrogen gas stably. From these results, it was considered that the degradation of sensor response in humid atmosphere was mainly dominated by adsorbing water on Pt catalyst surface.
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  • Rawintra Eamrat, Yuya Tsutsumi, Tatsuru Kamei, Willawan Khanichaidecha, Yasuhiro Tanaka, Futaba Kazama
    Journal of Water and Environment Technology
    2017 Volume 15 Issue 2 65-75
    Published: 2017
    Released: April 10, 2017
    JOURNALS FREE ACCESS

    Nitrate contamination of groundwater has become a serious issue affecting the quality of drinking water and human health. An energy-efficient, low-cost, and simple reactor was developed to remove nitrate via hydrogenotrophic denitrification (HD). Hydrogen (H2) supply was optimized by using a continuous supply of hydrogen (1–15 mL/min). The results revealed that the optimal condition was 5 mL/min, which yielded a nitrogen removal efficiency of 86.4% and a hydrogen effectiveness of 199 mg-N/g-H2. In the subsequent experiment, an intermittent hydrogen supply was used to improve the hydrogen effectiveness and hydrogen consumption. Using a cycle with a short period of hydrogen supply (3 min with hydrogen supply and 7 min with no hydrogen supply), excellent nitrogen removal efficiency (96.5%) was achieved, and the hydrogen effectiveness increased to 744 mg-N/g-H2. Furthermore, bacteria belonging to the Proteobacteria phylum and Betaproteobacteria class were the major components of the microbial community. However, Hydrogenophaga spp. (39.3%) was dominant under the continuous system, whereas Thauera spp. (58.5%) was the most abundant species under the intermittent system. In this study, Hydrogenophaga spp., Thauera spp., and Rhodocyclaceae, which were responsible for HD, afforded in efficient nitrogen removal from groundwater.

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  • Toshikazu ABE, Arihiro NOMURA, Tooru AMAYA, Yoshitaka YAMAKI, Tooru KUSANO, Hironori TAKANO
    Journal of Ion Exchange
    2003 Volume 14 Issue Supplement 273-276
    Published: July 14, 2003
    Released: March 18, 2010
    JOURNALS FREE ACCESS
    In this paper, we report on our research an the use of the ultraviolet (UV) oxidation method to remove total organic carbon (TOC), while focusing on the phenomenon that dissolved oxygen (DO) increases at outlet of the column packed with ion exchange resins. In addition, we also researched the behavior of hydrogen peroxide that is said to be in an equilibrium state with OH (hydroxy) radical. As a result, it was found that hydrogen peroxide is decomposed/deoxidized in the ion exchange column, which leads to a DO increase at outlet of the column.
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  • Yufeng Sun, Rintarou Ueji, Yoshiaki Morisada, Hidetoshi Fujii
    Preprints of the National Meeting of JWS
    2014 Volume 2014s 105
    Published: 2014
    Released: June 25, 2014
    CONFERENCE PROCEEDINGS FREE ACCESS
    The blister formation can be suppressed in the FSWed SPCC plates and it shows unobvious hydrogen embrittlement compared with that of the BM. However, in the HAZ of the welds hydrogen induced internal crack occurred and resulted in the degradation of the mechanical properties of the samples.
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  • Toshiaki KABE, Masazumi GODO, Atsushi ISHIHARA, Weihua QIAN, Hiroyuki OKI
    Journal of The Japan Petroleum Institute
    1998 Volume 41 Issue 2 164-167
    Published: March 01, 1998
    Released: October 15, 2008
    JOURNALS FREE ACCESS
    The hydrogen exchange of coal tar and model compounds of coal tar with water was investigated using a tritium tracer method to elucidate the mobility of hydrogen in coal tar. The reactions at several temperatures in the range from 50 to 300°C were carried out using a batch reactor for 1-12h. The hydrogen exchange ratio (HER) of coal tar with water approached a constant value at 100°C after 6h; however, the HER of coal tar increased remarkably at 200°C and at 300°C with time. From the results obtained from the hydrogen exchange of naphthol and indole as model compounds of coal tar, it was proposed that only hydrogen in functional groups with hetero-atom was exchangeable at 100°C while the hydrogen in the aromatic ring substituted by functional groups with hetero-atom also became exchangeable at 300°C. In contrast to this, the hydrogen in naphthalene hardly exchanged with water even at 300°C. Therefore, it was suggested that the constant value of HER of coal tar at 100°C represented the amount of hydrogen in the coal-tar functional groups with hetero-atom such as hydroxyl group and imino group. It was found that the tritium tracer method was an efficient approach to elucidate the behavior of hydrogen in coal tar and to determine the content of hydrogen related to the functional groups with hetero-atom in coal tar.
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  • N. Matubayasi, C. Wakai, M. Nakahara
    The Review of High Pressure Science and Technology
    1998 Volume 7 1112-1114
    Published: March 03, 1998
    Released: August 07, 2009
    JOURNALS FREE ACCESS
    The proton chemical shift of water is measured at temperatures up to 400°C and densities of 0. 19, 0. 29, 0. 41, 0. 49, and 0. 60 g/cm3. The magnetic susceptibility correction is made in order to express the chemical shift relative to an isolated water molecule in dilute gas . The chemical shift is related to the average number of hydrogen bonds in which a water molecule is involved. It is found that the hydrogen bonding persists at supercritical temperatures and that the average number of hydrogen bonds is at least one for a water molecule in the supercritical densities . The density dependence of the chemical shift at supercritical temperatures is analyzed on the basis of statistical thermodynamics. It is shown that the hydrogen bonding is spatially more inhomogeneous at lower densities. The dipole moment of water at supercritical states is estimated from the number of hydrogen bonds. we perform the proton chemical shift measurements for a water molecule as a function of the density. than that in the gas phase, and this enhancement of supercritical water by fitting the experimentally determined number of hydrogen bonds.
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  • Yoshiyuki Urushibara, Osamu Simamura
    Bulletin of the Chemical Society of Japan
    1938 Volume 13 Issue 5 407
    Published: 1938
    Released: April 12, 2006
    JOURNALS FREE ACCESS
  • Keitaro Horikawa, Keita Yamaue, Hidetoshi Kobayashi
    MATERIALS TRANSACTIONS
    2010 Volume 51 Issue 12 2181-2187
    Published: December 01, 2010
    Released: November 25, 2010
    [Advance publication] Released: November 17, 2010
    JOURNALS FREE ACCESS
    When one side of the surface-modified ZrNi amorphous alloy membranes was hydrogen charged cathodically, the membrane with Pd plating bent rapidly with an increase in the hydrogen charging time. It was also found that the bending disappears completely when hydrogen gas was released from the specimen by heating. The repetitious bending movement was identified by a combination of hydrogen absorption and desorption without any surface damages in the membrane with Pd plating. On the basis of an X-ray diffraction analysis of the specimen surfaces before and after hydrogen charging, it was shown that the absorbed hydrogen was simply solved in the specimens and did not form hydrides during the bending. The hydrogen microprint technique revealed that the hydrogen-induced bending deformation was closely related to the gradient of the hydrogen concentration in the thickness direction of the membranes.
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  • Kanao Fukuda, Joichi Sugimura
    Tribology Online
    2013 Volume 8 Issue 1 22-27
    Published: January 31, 2013
    Released: January 31, 2013
    JOURNALS FREE ACCESS
    The authors have clarified that trace impurities such as water and oxygen inevitably contained in a hydrogen environment influence friction and wear of metallic materials substantially and even often govern them. In this study, an experimental technique was devised to enable sliding tests in a hydrogen environment which contains controlled concentration of water and virtually no oxygen as impurities. By comparing data of Fe sliding tests between this study and our previous studies, the influences of water and oxygen were understood separately. Water without oxygen as impurity in a hydrogen environment decreased wear of pure Fe while oxygen in additional to water increased the wear. Sliding of pure Fe consumed water when a hydrogen environment contained only water while it produced water and consumed oxygen when the environment contained both water and oxygen. The number of water molecules consumed by sliding in a hydrogen environment with water more than 5,000 ppb and without oxygen was larger than the estimated number of nascent Fe atoms by sliding. This suggests that multi-layer adsorption of water molecules decreased the wear of pure Fe.
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  • Naoshi Izumi, Takehiro Morita, Joichi Sugimura
    Tribology Online
    2011 Volume 6 Issue 2 148-154
    Published: January 31, 2011
    Released: January 31, 2011
    JOURNALS FREE ACCESS
    Fretting wear tests on a bearing steel under gross slip condition were conducted in hydrogen and nitrogen gas environments containing water at 2 to 70 ppm using a new gas-tight chamber. Wear in hydrogen and nitrogen is sensitive to the water content of the gases and it increases as the water content increases. Water in these environmental gases reduces the coefficient of friction during the early cycles of experiments. Furthermore, exposure of the test specimens to high pressure hydrogen (40 MPa, 373 K, 200 hours) before the experiments enhances wear. These findings are consistent with the findings obtained in the authors' previous study, wherein the water content should have been higher and a comparison between hydrogen and nitrogen was not carried out because of insufficient control of water content. In this paper it is shown that wear in hydrogen is slightly larger than in nitrogen.
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