WorldWideScience

Sample records for on-board chemical hydrogen

  1. Board on chemical sciences and technology

    International Nuclear Information System (INIS)

    1991-01-01

    The Board on Chemical Sciences and Technology organizes and provides direction for standing and ad-hoc committees charged with addressing specific issues relevant to the continued health of the chemical sciences and technology community. Studies currently under the oversight of the BCST include a major survey of the chemical sciences, a complementary survey of chemical engineering, an examination of the problems of biohazards in the laboratory, and an analysis of the roots and magnitude of the problem of obsolescent facilities for research and teaching in departments in the chemical sciences and engineering. The Board continues to respond to specific agency requests for program assessments and advice. BCST members are designated to serve as liaison with major federal agencies or departments that support research in order to help identify ways for the Board to assist these organizations. The BCST maintains close contact with professional societies and non-governmental organizations that share the Board's concern for the health of chemical sciences and technology. Individual Board members are assigned responsibility for liaison with the American Chemical Society, the American Institute of Chemical Engineers, the American Society of Biological Chemists, the Council for Chemical Research, the NAS Chemistry and Biochemistry Sections, and the National Academy of Engineering. In the past few years, the Board has served as a focus and a forum for a variety of issues that relate specifically to the health of chemistry

  2. Board on chemical sciences and technology

    International Nuclear Information System (INIS)

    1991-01-01

    The Board on Chemical Sciences and Technology organizes and provides direction for standing and ad hoc committees charged with addressing specific issues relevant to the continued health of the chemical sciences and technology community. Studies currently under the oversight of the BCST include a major survey of chemical engineering, an examination of the problems of biohazards in the laboratory, and an analysis of the roots and magnitude of the problem of obsolescent facilities for research and teaching in departments in the chemical sciences and engineering. The Board continues to respond to specific agency requests for program assessments and advice. BCST members are designated to serve as liaison with major federal agencies or departments that support research in order to help identify ways for the board to assist the these organizations. The BCST also maintains close contact with professional societies and nongovernmental organizations that share the Board's concern for the health of chemical sciences and technology. Individual Board members are assigned responsibility for liaison with the American Chemical Society, the American Institute of Chemical Engineers, the American Society of Biological Chemists, the Council for Chemical Research, the Chemistry and Biochemistry Sections of the National Academy of Sciences (NAS), and the National Academy of Engineering (NAE). In the past few years, the Board has served as a focus and a forum for a variety of issues that relate specifically to the health of chemistry. A sampling of these concerns include: industry-university cooperation; basic research funding in DOD, DOE, NIH, and NSF; basic research in the chemistry of life processes; basic research in biochemical engineering; basic research in the science and technology of new materials; and undergraduate education in chemistry and chemical engineering

  3. A review on on-board challenges of magnesium-based hydrogen storage materials for automobile applications

    Science.gov (United States)

    Rahman, Md. Wasikur

    2017-06-01

    The attempt of the review is to realize on-board hydrogen storage technologies concerning magnesium based solid-state matrix to allow fuel cell devices to facilitate sufficient storage capacity, cost, safety and performance requirements to be competitive with current vehicles. Hydrogen, a potential and clean fuel, can be applied in the state-of-the-art technology of `zero emission' vehicles. Hydrogen economy infrastructure both for stationary and mobile purposes is complicated due to its critical physico-chemical properties and materials play crucial roles in every stage of hydrogen production to utilization in fuel cells in achieving high conversion efficiency, safety and robustness of the technologies involved. Moreover, traditional hydrogen storage facilities are rather complicated due to its anomalous properties such as highly porous solids and polymers have intrinsic microporosity, which is the foremost favorable characteristics of fast kinetics and reversibility, but the major drawback is the low storage capacity. In contrast, metal hydrides and complex hydrides have high hydrogen storage capacity but thermodynamically unfavorable. Therefore, hydrogen storage is a real challenge to realize `hydrogen economy' that will solve the critical issues of humanity such as energy depletion, greenhouse emission, air pollution and ultimately climate change. Magnesium based materials, particularly magnesium hydride (MgH2) has been proposed as a potential hydrogen storage material due to its high gravimetric and volumetric capacity as well as environmentally benign properties to work the grand challenge out.

  4. Board on chemical sciences and technology

    International Nuclear Information System (INIS)

    1991-01-01

    The Board has completed five reports since June 1988. Biosafety in the Laboratory: Prudent Practices for Handling and Disposal of Infectious Materials is a comprehensive review of the principles and practices of biological safety in the laboratory. Currently in press, it promises to be a landmark publication in this field, comparable to the Board's two previous studies on handling and disposal of chemicals in laboratories. Chemical Processes and Products in Severe Nuclear Reactor Accidents: Report of a Workshop evaluates the quality and relevance of existing high-temperature thermodynamic and kinetic data to the analysis of light-water reactor accidents. A number of areas where important data was deemed to be lacking or inadequate were identified to provide a sound basis for predicting the behavior of fission products, fuel, and other materials in nuclear reactors during a severe accident leading to radioactivity release. Training Requirements for Chemists in Nuclear Medicine, Nuclear Industry, and Related Areas assesses the training requirements for chemists in nuclear medicine, nuclear industry, and related areas. Finally, the Board's Air Force Office of Scientific Research High Energy Density Materials Panel has completed two program evaluation reports on this Air Force program

  5. Amineborane Based Chemical Hydrogen Storage - Final Report

    International Nuclear Information System (INIS)

    Sneddon, Larry G.

    2011-01-01

    The development of efficient and safe methods for hydrogen storage is a major hurdle that must be overcome to enable the use of hydrogen as an alternative energy carrier. The objectives of this project in the DOE Center of Excellence in Chemical Hydride Storage were both to develop new methods for on-demand, low temperature hydrogen release from chemical hydrides and to design high-conversion off-board methods for chemical hydride regeneration. Because of their reactive protic (N-H) and hydridic (B-H) hydrogens and high hydrogen contents, amineboranes such as ammonia borane, NH 3 BH 3 (AB), 19.6-wt% H 2 , and ammonia triborane NH 3 B 3 H 7 (AT), 17.7-wt% H 2 , were initially identified by the Center as promising, high-capacity chemical hydrogen storage materials with the potential to store and deliver molecular hydrogen through dehydrogenation and hydrolysis reactions. In collaboration with other Center partners, the Penn project focused both on new methods to induce amineborane H 2 -release and on new strategies for the regeneration the amineborane spent-fuel materials. The Penn approach to improving amineborane H 2 -release focused on the use of ionic liquids, base additives and metal catalysts to activate AB dehydrogenation and these studies successfully demonstrated that in ionic liquids the AB induction period that had been observed in the solid-state was eliminated and both the rate and extent of AB H2-release were significantly increased. These results have clearly shown that, while improvements are still necessary, many of these systems have the potential to achieve DOE hydrogen-storage goals. The high extent of their H 2 -release, the tunability of both their H 2 materials weight-percents and release rates, and their product control that is attained by either trapping or suppressing unwanted volatile side products, such as borazine, continue to make AB/ionic-liquid based systems attractive candidates for chemical hydrogen storage applications. These

  6. Amineborane Based Chemical Hydrogen Storage - Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Sneddon, Larry G.

    2011-04-21

    The development of efficient and safe methods for hydrogen storage is a major hurdle that must be overcome to enable the use of hydrogen as an alternative energy carrier. The objectives of this project in the DOE Center of Excellence in Chemical Hydride Storage were both to develop new methods for on-demand, low temperature hydrogen release from chemical hydrides and to design high-conversion off-board methods for chemical hydride regeneration. Because of their reactive protic (N-H) and hydridic (B-H) hydrogens and high hydrogen contents, amineboranes such as ammonia borane, NH3BH3 (AB), 19.6-wt% H2, and ammonia triborane NH3B3H7 (AT), 17.7-wt% H2, were initially identified by the Center as promising, high-capacity chemical hydrogen storage materials with the potential to store and deliver molecular hydrogen through dehydrogenation and hydrolysis reactions. In collaboration with other Center partners, the Penn project focused both on new methods to induce amineborane H2-release and on new strategies for the regeneration the amineborane spent-fuel materials. The Penn approach to improving amineborane H2-release focused on the use of ionic liquids, base additives and metal catalysts to activate AB dehydrogenation and these studies successfully demonstrated that in ionic liquids the AB induction period that had been observed in the solid-state was eliminated and both the rate and extent of AB H2-release were significantly increased. These results have clearly shown that, while improvements are still necessary, many of these systems have the potential to achieve DOE hydrogen-storage goals. The high extent of their H2­-release, the tunability of both their H2 materials weight-percents and release rates, and their product control that is attained by either trapping or suppressing unwanted volatile side products, such as borazine, continue to make AB/ionic­-liquid based systems attractive candidates for chemical hydrogen storage applications. These studies also

  7. Final Technical Report for GO15056 Millennium Cell: Development of an Advanced Chemical Hydrogen Storage and Generation System

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Oscar [Millennium Cell Inc., Eatontown, NJ (United States)

    2017-02-22

    The objectives of this project are to increase system storage capacity by improving hydrogen generation from concentrated sodium borohydride, with emphasis on reactor and system engineering; to complete a conceptual system design based on sodium borohydride that will include key technology improvements to enable a hydrogen fuel system that will meet the systembased storage capacity of 1.2 kWh/L (36 g H2/L) and 1.5 kWh/kg (45 g H2/kg), by the end of FY 2007; and to utilize engineering expertise to guide Center research in both off-board chemical hydride regeneration and on-board hydrogen generation systems.

  8. Catalytic on-board hydrogen production from methanol and ammonia for mobile application

    Energy Technology Data Exchange (ETDEWEB)

    Soerijanto, H.

    2008-08-15

    This PhD thesis deals with the catalytic hydrogen production for mobile application, for example for the use in fuel cells for electric cars. Electric powered buses with fuel cells as driving system are well known, but the secure hydrogen storage in adequate amounts for long distance drive is still a topic of discussion. Methanol is an excellent hydrogen carrier. First of all it has a high H:C ratio and therefore a high energy density. Secondly the operating temperature of steam reforming of methanol is comparatively low (250 C) and there is no risk of coking since methanol has no C-C bond. Thirdly methanol is a liquid, which means that the present gasoline infrastructure can be used. For the further development of catalysts and for the construction of a reformer it is very important to characterize the catalysts very well. For the dimensioning and the control of an on-board production of hydrogen it is essential to draw accurately on the thermodynamic, chemical and kinetic data of the reaction. At the first part of this work the mesoporous Cu/ZrO{sub 2}/CeO{sub 2}-catalysts with various copper contents were characterized and their long-term stability and selectivity were investigated, and the kinetic data were determined. Carbon monoxide is generated by reforming of carbon containing material. This process is undesired since CO poisons the Pt electrode of the fuel cell. The separation of hydrogen by metal membranes is technically feasible and a high purity of hydrogen can be obtained. However, due to their high density this procedure is not favourable because of its energy loss. In this study a concept is presented, which enables an autothermal mode by application of ceramic membrane and simultaneously could help to deal with the CO problem. The search for an absolutely selective catalyst is uncertain. The production of CO can be neither chemically nor thermodynamically excluded, if carbon is present in the hydrogen carrier. Since enrichment or separation are

  9. Catalytic on-board hydrogen production from methanol and ammonia for mobile application

    Energy Technology Data Exchange (ETDEWEB)

    Soerijanto, H

    2008-08-15

    This PhD thesis deals with the catalytic hydrogen production for mobile application, for example for the use in fuel cells for electric cars. Electric powered buses with fuel cells as driving system are well known, but the secure hydrogen storage in adequate amounts for long distance drive is still a topic of discussion. Methanol is an excellent hydrogen carrier. First of all it has a high H:C ratio and therefore a high energy density. Secondly the operating temperature of steam reforming of methanol is comparatively low (250 C) and there is no risk of coking since methanol has no C-C bond. Thirdly methanol is a liquid, which means that the present gasoline infrastructure can be used. For the further development of catalysts and for the construction of a reformer it is very important to characterize the catalysts very well. For the dimensioning and the control of an on-board production of hydrogen it is essential to draw accurately on the thermodynamic, chemical and kinetic data of the reaction. At the first part of this work the mesoporous Cu/ZrO{sub 2}/CeO{sub 2}-catalysts with various copper contents were characterized and their long-term stability and selectivity were investigated, and the kinetic data were determined. Carbon monoxide is generated by reforming of carbon containing material. This process is undesired since CO poisons the Pt electrode of the fuel cell. The separation of hydrogen by metal membranes is technically feasible and a high purity of hydrogen can be obtained. However, due to their high density this procedure is not favourable because of its energy loss. In this study a concept is presented, which enables an autothermal mode by application of ceramic membrane and simultaneously could help to deal with the CO problem. The search for an absolutely selective catalyst is uncertain. The production of CO can be neither chemically nor thermodynamically excluded, if carbon is present in the hydrogen carrier. Since enrichment or separation are

  10. Li-Al-borohydride as a potential candidate for on-board hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Lindemann, Inge; Domenech Ferrer, Roger; Dunsch, Lothar; Schultz, Ludwig; Gutfleisch, Oliver [IFW Dresden, PO Box 270016, D-01171 Dresden (Germany); Filinchuk, Yaroslav [Swiss-Norwegian Beam Lines at ESRF, BP-220, 38043 Grenoble (France); Hagemann, Hans; Cerny, Radovan [University of Geneva, Crystallography and Physical Chemistry Department, 1211 Geneva (Switzerland)

    2010-07-01

    Recently, double-cation borohydride systems have attracted great interest. It was found that the desorption temperature of the borohydrides decreases with increasing electronegativity of the cation. Consequently, it is possible to tailor a feasible on-board hydrogen storage material by combination of appropriate cations. Li-Al-borohydride shows a desorption temperature suitable for applications ({approx} 70 C) combined with an high hydrogen density (17.2 wt.%). It was synthesised via high energy ball milling of AlCl{sub 3} and LiBH{sub 4}. The structure of the compound was obtained from high-resolution synchrotron powder diffraction and shows a unique complex structure within the borohydrides. The material was characterized by means of in-situ-Raman, DSC, TG and thermal desorption measurements to study its decomposition pathway. The desorption at {approx} 70 C results in the formation of LiBH{sub 4} while the high mass loss of about 20% points to the release of not only hydrogen but also diborane. This is right now the main drawback for applications because it hinders reversibility.

  11. Preliminary analyses on hydrogen diffusion through small break of thermo-chemical IS process hydrogen plant

    International Nuclear Information System (INIS)

    Somolova, Marketa; Terada, Atsuhiko; Takegami, Hiroaki; Iwatsuki, Jin

    2008-12-01

    Japan Atomic Energy Agency has been conducting a conceptual design study of nuclear hydrogen demonstration plant, that is, a thermal-chemical IS process hydrogen plant coupled with the High temperature Engineering Test Reactor (HTTR-IS), which will be planed to produce a large amount of hydrogen up to 1000m 3 /h. As part of the conceptual design work of the HTTR-IS system, preliminary analyses on small break of a hydrogen pipeline in the IS process hydrogen plant was carried out as a first step of the safety analyses. This report presents analytical results of hydrogen diffusion behaviors predicted with a CFD code, in which a diffusion model focused on the turbulent Schmidt number was incorporated. By modifying diffusion model, especially a constant accompanying the turbulent Schmidt number in the diffusion term, analytical results was made agreed well with the experimental results. (author)

  12. Chemical hydrogen storage material property guidelines for automotive applications

    Science.gov (United States)

    Semelsberger, Troy A.; Brooks, Kriston P.

    2015-04-01

    Chemical hydrogen storage is the sought after hydrogen storage media for automotive applications because of the expected low pressure operation (0.05 kg H2/kgsystem), and system volumetric capacities (>0.05 kg H2/Lsystem). Currently, the primary shortcomings of chemical hydrogen storage are regeneration efficiency, fuel cost and fuel phase (i.e., solid or slurry phase). Understanding the required material properties to meet the DOE Technical Targets for Onboard Hydrogen Storage Systems is a critical knowledge gap in the hydrogen storage research community. This study presents a set of fluid-phase chemical hydrogen storage material property guidelines for automotive applications meeting the 2017 DOE technical targets. Viable material properties were determined using a boiler-plate automotive system design. The fluid-phase chemical hydrogen storage media considered in this study were neat liquids, solutions, and non-settling homogeneous slurries. Material properties examined include kinetics, heats of reaction, fuel-cell impurities, gravimetric and volumetric hydrogen storage capacities, and regeneration efficiency. The material properties, although not exhaustive, are an essential first step in identifying viable chemical hydrogen storage material properties-and most important, their implications on system mass, system volume and system performance.

  13. Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices

    Science.gov (United States)

    Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R

    2014-11-18

    An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles.

  14. HySDeP: a computational platform for on-board hydrogen storage systems – hybrid high-pressure solid-state and gaseous storage

    DEFF Research Database (Denmark)

    Mazzucco, Andrea; Rokni, Masoud

    2016-01-01

    A computational platform is developed in the Modelica® language within the DymolaTM environment to provide a tool for the design and performance comparison of on-board hydrogen storage systems. The platform has been coupled with an open source library for hydrogen fueling stations to investigate...

  15. The development of a computational platform to design and simulate on-board hydrogen storage systems

    DEFF Research Database (Denmark)

    Mazzucco, Andrea; Rokni, Masoud

    2017-01-01

    A computational platform is developed in the Modelica® language within the Dymola™ environment to provide a tool for the design and performance comparison of on-board hydrogen storage systems. The platform has been coupled with an open source library for hydrogen fueling stations to investigate...... the vehicular tank within the frame of a complete refueling system. The two technologies that are integrated in the platform are solid-state hydrogen storage in the form of metal hydrides and compressed gas systems. In this work the computational platform is used to compare the storage performance of two tank...... to a storage capacity four times larger than a tube-in-tube solution of the same size. The volumetric and gravimetric densities of the shell and tube are 2.46% and 1.25% respectively. The dehydriding ability of this solution is proven to withstand intense discharging conditions....

  16. Liquid-phase chemical hydrogen storage: catalytic hydrogen generation under ambient conditions.

    Science.gov (United States)

    Jiang, Hai-Long; Singh, Sanjay Kumar; Yan, Jun-Min; Zhang, Xin-Bo; Xu, Qiang

    2010-05-25

    There is a demand for a sufficient and sustainable energy supply. Hence, the search for applicable hydrogen storage materials is extremely important owing to the diversified merits of hydrogen energy. Lithium and sodium borohydride, ammonia borane, hydrazine, and formic acid have been extensively investigated as promising hydrogen storage materials based on their relatively high hydrogen content. Significant advances, such as hydrogen generation temperatures and reaction kinetics, have been made in the catalytic hydrolysis of aqueous lithium and sodium borohydride and ammonia borane as well as in the catalytic decomposition of hydrous hydrazine and formic acid. In this Minireview we briefly survey the research progresses in catalytic hydrogen generation from these liquid-phase chemical hydrogen storage materials.

  17. Functionalization of Hydrogenated Chemical Vapour Deposition-Grown Graphene by On-Surface Chemical Reactions

    Czech Academy of Sciences Publication Activity Database

    Drogowska, Karolina; Kovaříček, Petr; Kalbáč, Martin

    2017-01-01

    Roč. 23, č. 17 (2017), s. 4022-4022 ISSN 1521-3765 Institutional support: RVO:61388955 Keywords : Chemical vapor deposition * Hydrogenation * Graphene Subject RIV: CF - Physical ; Theoretical Chemistry

  18. Surface properties of hydrogenated nanodiamonds: a chemical investigation.

    Science.gov (United States)

    Girard, H A; Petit, T; Perruchas, S; Gacoin, T; Gesset, C; Arnault, J C; Bergonzo, P

    2011-06-28

    Hydrogen terminations (C-H) confer to diamond layers specific surface properties such as a negative electron affinity and a superficial conductive layer, opening the way to specific functionalization routes. For example, efficient covalent bonding of diazonium salts or of alkene moieties can be performed on hydrogenated diamond thin films, owing to electronic exchanges at the interface. Here, we report on the chemical reactivity of fully hydrogenated High Pressure High Temperature (HPHT) nanodiamonds (H-NDs) towards such grafting, with respect to the reactivity of as-received NDs. Chemical characterizations such as FTIR, XPS analysis and Zeta potential measurements reveal a clear selectivity of such couplings on H-NDs, suggesting that C-H related surface properties remain dominant even on particles at the nanoscale. These results on hydrogenated NDs open up the route to a broad range of new functionalizations for innovative NDs applications development. This journal is © the Owner Societies 2011

  19. Key study on the potential of hydrazine bisborane for solid- and liquid-state chemical hydrogen storage.

    Science.gov (United States)

    Pylypko, Sergii; Petit, Eddy; Yot, Pascal G; Salles, Fabrice; Cretin, Marc; Miele, Philippe; Demirci, Umit B

    2015-05-04

    Hydrazine bisborane N2H4(BH3)2 (HBB; 16.8 wt %) recently re-emerged as a potential hydrogen storage material. However, such potential is controversial: HBB was seen as a hazardous compound up to 2010, but now it would be suitable for hydrogen storage. In this context, we focused on fundamentals of HBB because they are missing in the literature and should help to shed light on its effective potential while taking into consideration any risk. Experimental/computational methods were used to get a complete characterization data sheet, including, e.g., XRD, NMR, FTIR, Raman, TGA, and DSC. From the reported results and discussion, it is concluded that HBB has potential in the field of chemical hydrogen storage given that both thermolytic and hydrolytic dehydrogenations were analyzed. In solid-state chemical hydrogen storage, it cannot be used in the pristine state (risk of explosion during dehydrogenation) but can be used for the synthesis of derivatives with improved dehydrogenation properties. In liquid-state chemical hydrogen storage, it can be studied for room-temperature dehydrogenation, but this requires the development of an active and selective metal-based catalyst. HBB is a thus a candidate for chemical hydrogen storage.

  20. Chemical storage of hydrogen in few-layer graphene

    Science.gov (United States)

    Subrahmanyam, K. S.; Kumar, Prashant; Maitra, Urmimala; Govindaraj, A.; Hembram, K. P. S. S.; Waghmare, Umesh V.; Rao, C. N. R.

    2011-01-01

    Birch reduction of few-layer graphene samples gives rise to hydrogenated samples containing up to 5 wt % of hydrogen. Spectroscopic studies reveal the presence of sp3 C-H bonds in the hydrogenated graphenes. They, however, decompose readily on heating to 500 °C or on irradiation with UV or laser radiation releasing all the hydrogen, thereby demonstrating the possible use of few-layer graphene for chemical storage of hydrogen. First-principles calculations throw light on the mechanism of dehydrogenation that appears to involve a significant reconstruction and relaxation of the lattice. PMID:21282617

  1. Hydrogen for automotive applications and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Eberle, U. [Adam Opel GmbH, Ruesselsheim (Germany)

    2010-12-30

    The energy storage system is of decisive importance for all types of electric vehicles, in contrast to the case of vehicles powered by a conventional fossil fuel or bio-fuel based internal combustion engine. Two major alternatives exist and need to be discussed: on the one hand, there is the possibility of electrical energy storage using batteries, whilst on the other hand there is the storage of energy in chemical form as hydrogen and the application of a fuel cell as energy converter. Considering the latter concept, hydrogen is a promising energy carrier in future energy systems. However, storage of hydrogen is a substantial challenge, especially for applications in vehicles with fuel cells that use proton-exchange membranes (PEMs). Different methods for hydrogen storage are discussed, including high-pressure and cryogenic-liquid storage, adsorptive storage on high-surface-area adsorbents, chemical storage in metal hydrides and complex hydrides, and storage in boranes. For the latter chemical solutions, reversible options and hydrolytic release of hydrogen with off-board regeneration are both possible. Reforming of liquid hydrogen-containing compounds is also a possible means of hydrogen generation. The advantages and disadvantages of the different systems are compared. (orig.)

  2. The U.S. National Hydrogen Storage Project

    International Nuclear Information System (INIS)

    Sunita Satyapal; Carole Read; Grace Ordaz; John Petrovic; George Thomas

    2006-01-01

    Hydrogen is being considered by many countries as a potential energy carrier for vehicular applications. In the United States, hydrogen-powered vehicles must possess a driving range of greater than 300 miles in order to meet customer requirements and compete effectively with other technologies. For the overall vehicular fleet, this requires that a range of 5-13 kg of hydrogen be stored on-board. The storage of such quantities of hydrogen within vehicular weight, volume, and system cost constraints is a major scientific and technological challenge. The targets for on-board hydrogen storage were established in the U.S. through the FreedomCAR and Fuel partnership, a partnership among the U.S. Department of Energy, the U.S. Council for Automotive Research (USCAR) and major energy companies. In order to achieve these long-term targets, the Department of Energy established a National Hydrogen Storage Project to develop the areas of metal hydrides, chemical hydrogen storage, carbon-based and high-surface-area sorbent materials, and new hydrogen storage materials and concepts. The current status of vehicular hydrogen storage is reviewed and hydrogen storage research associated with the National Hydrogen Storage Project is discussed. (authors)

  3. Hydrogen concentration profiles and chemical bonding in silicon nitride

    International Nuclear Information System (INIS)

    Peercy, P.S.; Stein, H.J.; Doyle, B.L.; Picraux, S.T.

    1978-01-01

    The complementary technique of nuclear reaction analysis and infrared absorption were used to study the concentration profile and chemical bonding of hydrogen in silicon nitride for different preparation and annealing conditions. Silicon nitride prepared by chemical vapor deposition from ammonia-silane mixtures is shown to have hydrogen concentrations of 8.1 and 6.5 at.% for deposition temperatures of 750 and 900 0 C, respectively. Plasma deposition at 300 0 C from these gases results in hydrogen concentrations of approximately 22 at.%. Comparison of nuclear reaction analysis and infrared absorption measurements after isothermal annealing shows that all of the hydrogen retained in the films remains bonded to either silicon or nitrogen and that hydrogen release from the material on annealing is governed by various trap energies involving at least two N-H and one Si-H trap. Reasonable estimates of the hydrogen release rates can be made from the effective diffusion coefficient obtained from measurements of hydrogen migration in hydrogen implanted and annealed films

  4. Proceedings of the DOE chemical energy storage and hydrogen energy systems contracts review

    Energy Technology Data Exchange (ETDEWEB)

    1980-02-01

    Sessions were held on electrolysis-based hydrogen storage systems, hydrogen production, hydrogen storage systems, hydrogen storage materials, end-use applications and system studies, chemical heat pump/chemical energy storage systems, systems studies and assessment, thermochemical hydrogen production cycles, advanced production concepts, and containment materials. (LHK)

  5. Hydrogenation of rapeseed oil for production of liquid bio-chemicals

    International Nuclear Information System (INIS)

    Pinto, F.; Martins, S.; Gonçalves, M.; Costa, P.; Gulyurtlu, I.; Alves, A.; Mendes, B.

    2013-01-01

    Highlights: ► Production of renewable liquid hydrocarbons through rapeseed oil hydrogenation. ► Hydrogenation at lower temperature and lower hydrogen pressures. ► Test of a catalyst commonly employed in petrochemical industry. ► Improve of hydrogenation process viability by decreasing operational costs. ► Analysis of hydrogenated product applications as bio-chemicals. -- Abstract: The main objective of rapeseed oil hydrogenation tests was the production of liquid bio-chemicals to be used as renewable raw material for the production of several chemicals and in chemical synthesis to substitute petroleum derived stuff. As, hydrogenation of vegetable oils is already applied for the production of biofuels, the work done focused in producing aromatic compounds, due to their economic value. The effect of experimental conditions on rapeseed oil hydrogenation was studied, namely, reaction temperature and time with the aim of selecting the most favourable conditions to convert rapeseed oil into liquid valuable bio-chemicals. Rapeseed oil was hydrogenated at a hydrogen initial pressure of 1.10 MPa. Reaction temperature varied in the range from 200 °C to 400 °C, while reaction times between 6 and 180 min were tested. The performance of a commercial cobalt and molybdenum catalyst was also studied. The highest hydrocarbons yields were obtained at the highest temperature and reaction times tested. At a temperature of 400 °C and at the reaction time of 120 min hydrocarbons yield was about 92% in catalyst presence, while in the absence of the catalyst this value decreased to 85%. Hydrocarbons yield was even higher when the reaction time of 180 min was used in the presence of catalyst, as the yield of 97% was observed. At these conditions hydrocarbons formed had a high content of aromatic compounds, around 50%. For this reason, the viscosity values of hydrogenated oils were lower than that established by EN590, which together with hydrogenated liquids composition

  6. Demand and supply of hydrogen as chemical feedstock in USA

    Science.gov (United States)

    Huang, C. J.; Tang, K.; Kelley, J. H.; Berger, B. J.

    1979-01-01

    Projections are made for the demand and supply of hydrogen as chemical feedstock in USA. Industrial sectors considered are petroleum refining, ammonia synthesis, methanol production, isocyanate manufacture, edible oil processing, coal liquefaction, fuel cell electricity generation, and direct iron reduction. Presently, almost all the hydrogen required is produced by reforming of natural gas or petroleum fractions. Specific needs and emphases are recommended for future research and development to produce hydrogen from other sources to meet the requirements of these industrial sectors. The data and the recommendations summarized in this paper are based on the Workshop 'Supply and Demand of Hydrogen as Chemical Feedstock' held at the University of Houston on December 12-14, 1977.

  7. Hydrogen storage by physisorption on porous materials

    Energy Technology Data Exchange (ETDEWEB)

    Panella, B

    2006-09-13

    A great challenge for commercializing hydrogen powered vehicles is on-board hydrogen storage using economic and secure systems. A possible solution is hydrogen storage in light-weight solid materials. Here three principle storage mechanisms can be distinguished: i) absorption of hydrogen in metals ii) formation of compounds with ionic character, like complex hydrides and iii) physisorption (or physical adsorption) of hydrogen molecules on porous materials. Physical adsorption exhibits several advantages over chemical hydrogen storage as for example the complete reversibility and the fast kinetics. Two classes of porous materials were investigated for physical hydrogen storage, i.e. different carbon nanostructures and crystalline metal-organic frameworks possessing extremely high specific surface area. Hydrogen adsorption isotherms were measured using a Sieverts' apparatus both at room temperature and at 77 K at pressures up to the saturation regime. Additionally, the adsorption sites of hydrogen in these porous materials were identified using thermal desorption spectroscopy extended to very low temperatures (down to 20 K). Furthermore, the adsorbed hydrogen phase was studied in various materials using Raman spectroscopy at different pressures and temperatures. The results show that the maximum hydrogen storage capacity of porous materials correlates linearly with the specific surface area and is independent of structure and composition. In addition the pore structure of the adsorbent plays an important role for hydrogen storage since the adsorption sites for H2 could be assigned to pores possessing different dimensions. Accordingly it was shown that small pores are necessary to reach high storage capacities already at low pressures. This new understanding may help to tailor and optimize new porous materials for hydrogen storage. (orig.)

  8. Hydrogen storage by physisorption on porous materials

    Energy Technology Data Exchange (ETDEWEB)

    Panella, B.

    2006-09-13

    A great challenge for commercializing hydrogen powered vehicles is on-board hydrogen storage using economic and secure systems. A possible solution is hydrogen storage in light-weight solid materials. Here three principle storage mechanisms can be distinguished: i) absorption of hydrogen in metals ii) formation of compounds with ionic character, like complex hydrides and iii) physisorption (or physical adsorption) of hydrogen molecules on porous materials. Physical adsorption exhibits several advantages over chemical hydrogen storage as for example the complete reversibility and the fast kinetics. Two classes of porous materials were investigated for physical hydrogen storage, i.e. different carbon nanostructures and crystalline metal-organic frameworks possessing extremely high specific surface area. Hydrogen adsorption isotherms were measured using a Sieverts' apparatus both at room temperature and at 77 K at pressures up to the saturation regime. Additionally, the adsorption sites of hydrogen in these porous materials were identified using thermal desorption spectroscopy extended to very low temperatures (down to 20 K). Furthermore, the adsorbed hydrogen phase was studied in various materials using Raman spectroscopy at different pressures and temperatures. The results show that the maximum hydrogen storage capacity of porous materials correlates linearly with the specific surface area and is independent of structure and composition. In addition the pore structure of the adsorbent plays an important role for hydrogen storage since the adsorption sites for H2 could be assigned to pores possessing different dimensions. Accordingly it was shown that small pores are necessary to reach high storage capacities already at low pressures. This new understanding may help to tailor and optimize new porous materials for hydrogen storage. (orig.)

  9. Down Select Report of Chemical Hydrogen Storage Materials, Catalysts, and Spent Fuel Regeneration Processes

    Energy Technology Data Exchange (ETDEWEB)

    Ott, Kevin; Linehan, Sue; Lipiecki, Frank; Aardahl, Christopher L.

    2008-08-24

    The DOE Hydrogen Storage Program is focused on identifying and developing viable hydrogen storage systems for onboard vehicular applications. The program funds exploratory research directed at identifying new materials and concepts for storage of hydrogen having high gravimetric and volumetric capacities that have the potential to meet long term technical targets for onboard storage. Approaches currently being examined are reversible metal hydride storage materials, reversible hydrogen sorption systems, and chemical hydrogen storage systems. The latter approach concerns materials that release hydrogen in endothermic or exothermic chemical bond-breaking processes. To regenerate the spent fuels arising from hydrogen release from such materials, chemical processes must be employed. These chemical regeneration processes are envisioned to occur offboard the vehicle.

  10. Effect of chemical treatments on hydrogen storage behaviors of multi-walled carbon nanotubes

    International Nuclear Information System (INIS)

    Lee, Seul-Yi; Park, Soo-Jin

    2010-01-01

    In this work, the hydrogen storage behaviors of chemically treated multi-walled carbon nanotubes (MWNTs) were investigated. The surface properties of the functionalized MWNTs were confirmed by Fourier transfer infrared spectroscopy, X-ray diffraction, the Boehm titration method, and zeta-potential measurements. The hydrogen storage capacity of the MWNTs was evaluated at 298 K and 100 bar. In the experimental results, it was found that the chemical treatments introduced functional groups onto the MWNT surfaces. The amount of hydrogen storage was enhanced, by acidic surface treatment, to 0.42 wt.% in the acidic-treated MWNTs compared with 0.26 wt.% in the as-received MWNTs. Meanwhile, the basic surface treatment actually reduced the hydrogen storage capacity, to 0.24 wt.% in the basic-treated MWNTs sample. Consequently, it could be concluded that hydrogen storage is greatly influenced by the acidic characteristics of MWNT surfaces, resulting in enhanced electron acceptor-donor interaction at interfaces.

  11. Molecular dynamics simulation of chemical sputtering of hydrogen atom on layer structured graphite

    International Nuclear Information System (INIS)

    Ito, A.; Wang, Y.; Irle, S.; Morokuma, K.; Nakamura, H.

    2008-10-01

    Chemical sputtering of hydrogen atom on graphite was simulated using molecular dynamics. Especially, the layer structure of the graphite was maintained by interlayer intermolecular interaction. Three kinds of graphite surfaces, flat (0 0 0 1) surface, armchair (1 1 2-bar 0) surface and zigzag (1 0 1-bar 0) surface, are dealt with as targets of hydrogen atom bombardment. In the case of the flat surface, graphene layers were peeled off one by one and yielded molecules had chain structures. On the other hand, C 2 H 2 and H 2 are dominant yielded molecules on the armchair and zigzag surfaces, respectively. In addition, the interaction of a single hydrogen isotope on a single graphene is investigated. Adsorption, reflection and penetration rates are obtained as functions of incident energy and explain hydrogen retention on layered graphite. (author)

  12. Chemical reaction between single hydrogen atom and graphene

    International Nuclear Information System (INIS)

    Ito, Atsushi; Nakamura, Hiroaki; Takayama, Arimichi

    2007-04-01

    We study chemical reaction between a single hydrogen atom and a graphene, which is the elemental reaction between hydrogen and graphitic carbon materials. In the present work, classical molecular dynamics simulation is used with modified Brenner's empirical bond order potential. The three reactions, that is, absorption reaction, reflection reaction and penetration reaction, are observed in our simulation. Reaction rates depend on the incident energy of the hydrogen atom and the graphene temperature. The dependence can be explained by the following mechanisms: (1) The hydrogen atom receives repulsive force by π-electrons in addition to nuclear repulsion. (2) Absorbing the hydrogen atom, the graphene transforms its structure to the 'overhand' configuration such as sp 3 state. (3) The hexagonal hole of the graphene is expanded during the penetration of the hydrogen atom. (author)

  13. Technical Analysis of Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Ali T-Raissi

    2005-01-14

    The aim of this work was to assess issues of cost, and performance associated with the production and storage of hydrogen via following three feedstocks: sub-quality natural gas (SQNG), ammonia (NH{sub 3}), and water. Three technology areas were considered: (1) Hydrogen production utilizing SQNG resources, (2) Hydrogen storage in ammonia and amine-borane complexes for fuel cell applications, and (3) Hydrogen from solar thermochemical cycles for splitting water. This report summarizes our findings with the following objectives: Technoeconomic analysis of the feasibility of the technology areas 1-3; Evaluation of the hydrogen production cost by technology areas 1; and Feasibility of ammonia and/or amine-borane complexes (technology areas 2) as a means of hydrogen storage on-board fuel cell powered vehicles. For each technology area, we reviewed the open literature with respect to the following criteria: process efficiency, cost, safety, and ease of implementation and impact of the latest materials innovations, if any. We employed various process analysis platforms including FactSage chemical equilibrium software and Aspen Technologies AspenPlus and HYSYS chemical process simulation programs for determining the performance of the prospective hydrogen production processes.

  14. Purdue Hydrogen Systems Laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Jay P Gore; Robert Kramer; Timothee L Pourpoint; P. V. Ramachandran; Arvind Varma; Yuan Zheng

    2011-12-28

    The Hydrogen Systems Laboratory in a unique partnership between Purdue University's main campus in West Lafayette and the Calumet campus was established and its capabilities were enhanced towards technology demonstrators. The laboratory engaged in basic research in hydrogen production and storage and initiated engineering systems research with performance goals established as per the USDOE Hydrogen, Fuel Cells, and Infrastructure Technologies Program. In the chemical storage and recycling part of the project, we worked towards maximum recycling yield via novel chemical selection and novel recycling pathways. With the basic potential of a large hydrogen yield from AB, we used it as an example chemical but have also discovered its limitations. Further, we discovered alternate storage chemicals that appear to have advantages over AB. We improved the slurry hydrolysis approach by using advanced slurry/solution mixing techniques. We demonstrated vehicle scale aqueous and non-aqueous slurry reactors to address various engineering issues in on-board chemical hydrogen storage systems. We measured the thermal properties of raw and spent AB. Further, we conducted experiments to determine reaction mechanisms and kinetics of hydrothermolysis in hydride-rich solutions and slurries. We also developed a continuous flow reactor and a laboratory scale fuel cell power generation system. The biological hydrogen production work summarized as Task 4.0 below, included investigating optimal hydrogen production cultures for different substrates, reducing the water content in the substrate, and integrating results from vacuum tube solar collector based pre and post processing tests into an enhanced energy system model. An automated testing device was used to finalize optimal hydrogen production conditions using statistical procedures. A 3 L commercial fermentor (New Brunswick, BioFlo 115) was used to finalize testing of larger samples and to consider issues related to scale up

  15. Purdue Hydrogen Systems Laboratory

    International Nuclear Information System (INIS)

    Gore, Jay P.; Kramer, Robert; Pourpoint, Timothee L.; Ramachandran, P.V.; Varma, Arvind; Zheng, Yuan

    2011-01-01

    The Hydrogen Systems Laboratory in a unique partnership between Purdue University's main campus in West Lafayette and the Calumet campus was established and its capabilities were enhanced towards technology demonstrators. The laboratory engaged in basic research in hydrogen production and storage and initiated engineering systems research with performance goals established as per the USDOE Hydrogen, Fuel Cells, and Infrastructure Technologies Program. In the chemical storage and recycling part of the project, we worked towards maximum recycling yield via novel chemical selection and novel recycling pathways. With the basic potential of a large hydrogen yield from AB, we used it as an example chemical but have also discovered its limitations. Further, we discovered alternate storage chemicals that appear to have advantages over AB. We improved the slurry hydrolysis approach by using advanced slurry/solution mixing techniques. We demonstrated vehicle scale aqueous and non-aqueous slurry reactors to address various engineering issues in on-board chemical hydrogen storage systems. We measured the thermal properties of raw and spent AB. Further, we conducted experiments to determine reaction mechanisms and kinetics of hydrothermolysis in hydride-rich solutions and slurries. We also developed a continuous flow reactor and a laboratory scale fuel cell power generation system. The biological hydrogen production work summarized as Task 4.0 below, included investigating optimal hydrogen production cultures for different substrates, reducing the water content in the substrate, and integrating results from vacuum tube solar collector based pre and post processing tests into an enhanced energy system model. An automated testing device was used to finalize optimal hydrogen production conditions using statistical procedures. A 3 L commercial fermentor (New Brunswick, BioFlo 115) was used to finalize testing of larger samples and to consider issues related to scale up. Efforts

  16. Fuel cell cars in a microgrid for synergies between hydrogen and electricity networks

    NARCIS (Netherlands)

    Alavi, F.; Park Lee, H.; van de Wouw, N.; De Schutter, B.H.K.; Lukszo, Z.

    2017-01-01

    Fuel cell electric vehicles convert chemical energy of hydrogen into electricity to power their motor. Since cars are used for transport only during a small part of the time, energy stored in the on-board hydrogen tanks of fuel cell vehicles can be used to provide power when cars are parked. In

  17. Fuel cell cars in a microgrid for synergies between hydrogen and electricity networks

    NARCIS (Netherlands)

    Alavi, F.; Park Lee, E.; van de Wouw, N.; de Schutter, B.; Lukszo, Z.

    2017-01-01

    Fuel cell electric vehicles convert chemical energy of hydrogen into electricity to power their motor. Since cars are used for transport only during a small part of the time, energy stored in the on-board hydrogen tanks of fuel cell vehicles can be used to provide power when cars are parked. In this

  18. U.S. Department of Energy Hydrogen Storage Cost Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Law, Karen; Rosenfeld, Jeffrey; Han, Vickie; Chan, Michael; Chiang, Helena; Leonard, Jon

    2013-03-11

    The overall objective of this project is to conduct cost analyses and estimate costs for on- and off-board hydrogen storage technologies under development by the U.S. Department of Energy (DOE) on a consistent, independent basis. This can help guide DOE and stakeholders toward the most-promising research, development and commercialization pathways for hydrogen-fueled vehicles. A specific focus of the project is to estimate hydrogen storage system cost in high-volume production scenarios relative to the DOE target that was in place when this cost analysis was initiated. This report and its results reflect work conducted by TIAX between 2004 and 2012, including recent refinements and updates. The report provides a system-level evaluation of costs and performance for four broad categories of on-board hydrogen storage: (1) reversible on-board metal hydrides (e.g., magnesium hydride, sodium alanate); (2) regenerable off-board chemical hydrogen storage materials(e.g., hydrolysis of sodium borohydride, ammonia borane); (3) high surface area sorbents (e.g., carbon-based materials); and 4) advanced physical storage (e.g., 700-bar compressed, cryo-compressed and liquid hydrogen). Additionally, the off-board efficiency and processing costs of several hydrogen storage systems were evaluated and reported, including: (1) liquid carrier, (2) sodium borohydride, (3) ammonia borane, and (4) magnesium hydride. TIAX applied a bottom-up costing methodology customized to analyze and quantify the processes used in the manufacture of hydrogen storage systems. This methodology, used in conjunction with ® software and other tools, developed costs for all major tank components, balance-of-tank, tank assembly, and system assembly. Based on this methodology, the figure below shows the projected on-board high-volume factory costs of the various analyzed hydrogen storage systems, as designed. Reductions in the key cost drivers may bring hydrogen storage system costs closer to this DOE target

  19. 76 FR 64022 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting

    Science.gov (United States)

    2011-10-17

    ... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting AGENCY: Environmental Protection Agency (EPA). ACTION: Lifting of Administrative Stay for Hydrogen Sulfide. SUMMARY: EPA is announcing... (EPCRA) section 313 toxic chemical release reporting requirements for hydrogen sulfide (Chemical...

  20. Chemical identification of contaminants in paper and board food contact materials

    DEFF Research Database (Denmark)

    Bengtström, Linda

    Paper and board are used for a variety of food contact materials, such as baking paper, microwave popcorn bags and packaging for cereals as well as fast foods. Despite this extensive use, there are currently large data gaps about the chemical composition of different paper and board food contact...

  1. Sodium hydrazinidoborane: a chemical hydrogen-storage material.

    Science.gov (United States)

    Moury, Romain; Demirci, Umit B; Ichikawa, Takayuki; Filinchuk, Yaroslav; Chiriac, Rodica; van der Lee, Arie; Miele, Philippe

    2013-04-01

    Herein, we present the successful synthesis and full characterization (by (11) B magic-angle-spinning nuclear magnetic resonance spectroscopy, infrared spectroscopy, powder X-ray diffraction) of sodium hydrazinidoborane (NaN2 H3 BH3 , with a hydrogen content of 8.85 wt %), a new material for chemical hydrogen storage. Using lab-prepared pure hydrazine borane (N2 H4 BH3 ) and commercial sodium hydride as precursors, sodium hydrazinidoborane was synthesized by ball-milling at low temperature (-30 °C) under an argon atmosphere. Its thermal stability was assessed by thermogravimetric analysis and differential scanning calorimetry. It was found that under heating sodium hydrazinidoborane starts to liberate hydrogen below 60 °C. Within the range of 60-150 °C, the overall mass loss is as high as 7.6 wt %. Relative to the parent N2 H4 BH3 , sodium hydrazinidoborane shows improved dehydrogenation properties, further confirmed by dehydrogenation experiments under prolonged heating at constant temperatures of 80, 90, 95, 100, and 110 °C. Hence, sodium hydrazinidoborane appears to be more suitable for chemical hydrogen storage than N2 H4 BH3 . Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. On-Board Hydrogen Gas Production System For Stirling Engines

    Science.gov (United States)

    Johansson, Lennart N.

    2004-06-29

    A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed. A hydrogen production system for use in connection with Stirling engines. The production system generates hydrogen working gas and periodically supplies it to the Stirling engine as its working fluid in instances where loss of such working fluid occurs through usage through operation of the associated Stirling engine. The hydrogen gas may be generated by various techniques including electrolysis and stored by various means including the use of a metal hydride absorbing material. By controlling the temperature of the absorbing material, the stored hydrogen gas may be provided to the Stirling engine as needed.

  3. Radiation-chemical yields of molecular hydrogen formation in cyclohexane based alcohols

    International Nuclear Information System (INIS)

    Val'ter, A.I.; Kovalev, G.V.

    1988-01-01

    Molecular hydrogen radiation-chemical yields in γ-irradiated cyclohexanol, 1.2-cis- and 1.2-trans-cyclohexandiols and inositol are determined within the general problem frameworks of radiolysis mechanism for cyclohexanering-base alcohols. Irradiation was conducted at 77 and 293 K, dose rate - 4 Gy/s. Hydrogen concentration in all irradiated alcohols depends linearly on the dose. Radiation-chemical yields of H 2 and of stabilized radicals, as well, in the irradiated crystalline alcohols are analyzed depending on the irradiation temperature, alcohol molecular structure

  4. Spectroscopic ellipsometry on Si/SiO2/graphene tri-layer system exposed to downstream hydrogen plasma: Effects of hydrogenation and chemical sputtering

    International Nuclear Information System (INIS)

    Eren, Baran; Fu, Wangyang; Marot, Laurent; Calame, Michel; Steiner, Roland; Meyer, Ernst

    2015-01-01

    In this work, the optical response of graphene to hydrogen plasma treatment is investigated with spectroscopic ellipsometry measurements. Although the electronic transport properties and Raman spectrum of graphene change after plasma hydrogenation, ellipsometric parameters of the Si/SiO2/graphene tri-layer system do not change. This is attributed to plasma hydrogenated graphene still being electrically conductive, since the light absorption of conducting 2D materials does not depend on the electronic band structure. A change in the light transmission can only be observed when higher energy hydrogen ions (30 eV) are employed, which chemically sputter the graphene layer. An optical contrast is still apparent after sputtering due to the remaining traces of graphene and hydrocarbons on the surface. In brief, plasma treatment does not change the light transmission of graphene; and when it does, this is actually due to plasma damage rather than plasma hydrogenation

  5. Effect of chemically reduced palladium supported catalyst on sunflower oil hydrogenation conversion and selectivity

    Directory of Open Access Journals (Sweden)

    Abdulmajid Alshaibani

    2017-02-01

    Full Text Available Catalytic hydrogenation of sunflower oil was studied in order to improve the conversion and to reduce the trans-isomerization selectivity. The hydrogenation was performed using Pd–B/γ-Al2O3 prepared catalyst and Pd/Al2O3 commercial catalyst under similar conditions. The Pd–B/γ-Al2O3 catalyst was prepared by wet impregnation and chemical reduction processes. It was characterized by Brunauer–Emmett–Teller surface area analysis (BET, X-ray powder diffraction (XRD, scanning electron microscopy (SEM, and transmission electron microscopy (TEM. The result of sunflower oil hydrogenation on Pd–B/γ-Al2O3 catalyst showed a 17% higher conversion and a 23% lower trans-isomerization selectivity compared to the commercial Pd/Al2O3 catalyst. The chemical reduction of palladium supported catalyst using potassium borohydride (KBH4 has affected the Pd–B/γ-Al2O3 catalyst’s structure and particle size. These most likely influenced its catalytic performance toward higher conversion and lower trans-isomerization selectivity.

  6. Purification of free hydrogen or hydrogen combined in a gaseous mixture by chemical reactions with uranium

    International Nuclear Information System (INIS)

    Caron-Charles, M.; Gilot, B.

    1989-01-01

    Within the framework of the European fusion program, the authors are dealing with the tritium technology aspect. Hydrogen, free or under a combined form within a H 2 , N 2 , NH 3 , O 2 , gaseous mixture, can be purified by chemical reactions with uranium metal. The resulting reactions consist in absorbing the impurities without holding back H 2 . Working conditions have been defined according to two main goals: the formation of stable solid products, especially under hydrogenated atmosphere and the optimization of the material quantities to be used. Thermodynamical considerations have shown that the 950-1300 K temperature range should be suitable for this chemical process. Experiments performed with massive uranium set in a closed reactor at 973 K, have produced hydrogen according to the predicted reactions rates. But they have also pointed out the importance of interferences that might occur in the uranium-gas system, on the gases conversion rates. The comparison between the chemical kinetic ratings of the reactions of pure gases and the chemical kinetic ratings of the reactions of the same gases in mixture, has been set up. It proves that simultaneous reactions can modify the working conditions of the solid products formation, and particularly modify their structure. In this case, chemical kinetic ratings are increased up to their maximal value; that means surface phenomena are favoured as with uranium powder gases reactions. (orig.)

  7. Determination of trapping parameters and the chemical diffusion coefficient from hydrogen permeation experiments

    International Nuclear Information System (INIS)

    Svoboda, J.; Mori, G.; Prethaler, A.; Fischer, F.D.

    2014-01-01

    Highlights: • A modeling study for diffusion of hydrogen with traps is presented. • Introduction of a new chemical diffusion coefficient. • Density of traps and average depth of traps can be determined. • Lattice diffusion and sub-surface concentration of atomic hydrogen can be determined. - Abstract: An improved diffusion theory accounting for trapping effects is applied to evaluation of hydrogen permeation experiments performed for pure iron and pearlitic and martensitic steels. The trapping parameters as molar volume and depth of traps are determined by fitting experiments by simulations based on the theory. The concentration-dependent chemical diffusion coefficient of hydrogen is extracted indicating that the trapping effect on diffusion in pure iron and pearlitic steel is negligible. However, it is significant for martensitic steel, for which the chemical diffusion coefficient cannot be considered as concentration-independent as it is established in current standards

  8. Steam and partial oxidation reforming options for hydrogen production from fossil fuels for PEM fuel cells

    OpenAIRE

    Yousri M.A. Welaya; Mohamed M. El Gohary; Nader R. Ammar

    2012-01-01

    Proton exchange membrane fuel cell (PEM) generates electrical power from air and from hydrogen or hydrogen rich gas mixtures. Therefore, there is an increasing interest in converting current hydrocarbon based marine fuels such as natural gas, gasoline, and diesel into hydrogen rich gases acceptable to the PEM fuel cells on board ships. Using chemical flow sheeting software, the total system efficiency has been calculated. Natural gas appears to be the best fuel for hydrogen rich gas productio...

  9. Chemical Hydride Slurry for Hydrogen Production and Storage

    Energy Technology Data Exchange (ETDEWEB)

    McClaine, Andrew W

    2008-09-30

    The purpose of this project was to investigate and evaluate the attractiveness of using a magnesium chemical hydride slurry as a hydrogen storage, delivery, and production medium for automobiles. To fully evaluate the potential for magnesium hydride slurry to act as a carrier of hydrogen, potential slurry compositions, potential hydrogen release techniques, and the processes (and their costs) that will be used to recycle the byproducts back to a high hydrogen content slurry were evaluated. A 75% MgH2 slurry was demonstrated, which was just short of the 76% goal. This slurry is pumpable and storable for months at a time at room temperature and pressure conditions and it has the consistency of paint. Two techniques were demonstrated for reacting the slurry with water to release hydrogen. The first technique was a continuous mixing process that was tested for several hours at a time and demonstrated operation without external heat addition. Further work will be required to reduce this design to a reliable, robust system. The second technique was a semi-continuous process. It was demonstrated on a 2 kWh scale. This system operated continuously and reliably for hours at a time, including starts and stops. This process could be readily reduced to practice for commercial applications. The processes and costs associated with recycling the byproducts of the water/slurry reaction were also evaluated. This included recovering and recycling the oils of the slurry, reforming the magnesium hydroxide and magnesium oxide byproduct to magnesium metal, hydriding the magnesium metal with hydrogen to form magnesium hydride, and preparing the slurry. We found that the SOM process, under development by Boston University, offers the lowest cost alternative for producing and recycling the slurry. Using the H2A framework, a total cost of production, delivery, and distribution of $4.50/kg of hydrogen delivered or $4.50/gge was determined. Experiments performed at Boston

  10. Spectroscopic ellipsometry on Si/SiO{sub 2}/graphene tri-layer system exposed to downstream hydrogen plasma: Effects of hydrogenation and chemical sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Eren, Baran [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States); Fu, Wangyang; Marot, Laurent, E-mail: laurent.marot@unibas.ch; Calame, Michel; Steiner, Roland; Meyer, Ernst [Department of Physics, University of Basel, Klingelbergstrasse 82, CH-4056 Basel (Switzerland)

    2015-01-05

    In this work, the optical response of graphene to hydrogen plasma treatment is investigated with spectroscopic ellipsometry measurements. Although the electronic transport properties and Raman spectrum of graphene change after plasma hydrogenation, ellipsometric parameters of the Si/SiO2/graphene tri-layer system do not change. This is attributed to plasma hydrogenated graphene still being electrically conductive, since the light absorption of conducting 2D materials does not depend on the electronic band structure. A change in the light transmission can only be observed when higher energy hydrogen ions (30 eV) are employed, which chemically sputter the graphene layer. An optical contrast is still apparent after sputtering due to the remaining traces of graphene and hydrocarbons on the surface. In brief, plasma treatment does not change the light transmission of graphene; and when it does, this is actually due to plasma damage rather than plasma hydrogenation.

  11. New Transition metal assisted complex borohydrides for hydrogen storage

    International Nuclear Information System (INIS)

    Sesha Srinivasan; Elias Lee Stefanakos; Yogi Goswami

    2006-01-01

    High capacity hydrogen storage systems are indeed essential for the on-board vehicular application that leads to the pollution free environment. Apart from the various hydrogen storage systems explored in the past, complex hydrides involving light weight alkali/alkaline metals exhibits promising hydrogenation/ dehydrogenation characteristics. New transition metal assisted complex borohydrides [Zn(BH 4 ) 2 ] have been successfully synthesized by an inexpensive mechano-chemical process. These complex hydrides possesses gravimetric hydrogen storage capacity of ∼8.4 wt.% at around 120 C. We have determined the volumetric hydrogen absorption and desorption of these materials for a number of cycles. Another complex borohydride mixture LiBH 4 /MgH 2 catalyzed with ZnCl 2 has been synthesized and characterized using various analytical techniques. (authors)

  12. Research on the surface chemical behavior of uranium metal in hydrogen atmosphere by XPS

    International Nuclear Information System (INIS)

    Fu Xiaoguo; Wang Xiaolin; Yu Yong; Zhao Zhengping

    2001-01-01

    The surface chemical behavior clean uranium metal in hydrogen atmosphere at 100 and 200 degree C is studied by X-ray photoelectron spectroscopy (XPS), respectively. It leads to hydriding reaction when the hydrogen exposure is 12.0 Pa·s, and the U4f 7/2 binding energy of UH 3 is found to be 378.7 eV. The higher temperature (200 degree C) is beneficial to UH 3 formation at the same hydrogen exposures. XPS elemental depth profiles indicate that the distribution of uranium surface layer is UO 2 , UH 3 and U after exposure to 174.2 Pa·s hydrogen

  13. Quantum chemical simulation of hydrogen like states in silicon and diamond

    International Nuclear Information System (INIS)

    Gel'fand, R.B.; Gordeev, V.A.; Gorelkinskij, Yu.V.

    1989-01-01

    The quantum-chemical methods of the complete neglect of differential overlap (CNDO) and intermediate neglect of differential overlap (INDO) are used to calculate the electronic structure of atomic hydrogen (muonium) located at different interstital sites of the silicon and diamond crystal lattices. The electronic g- and hyperfine interaction tensors of the impure atom are determined.The results obtained are compared with the experimental data on the 'normal' (Mu') and 'anomalous' (Mu * ) muonium centers as well as on the hydrogen-bearing Si-AA9 EPR center which is a hydrogen-bearing analogue of (Mu * ). The most likely localization sites for hydrogen (muonium) atoms in silicon and diamond crystals are established. 22 refs

  14. Board on chemical sciences and technology

    International Nuclear Information System (INIS)

    1988-01-01

    Current and Ongoing Projects include: Committee on Nuclear and Radiochemistry; Committee on Nuclear and Radiochemistry Workshop on Training Requirements for Chemists in Nuclear Medicine, Nuclear Industry, and Related Areas; Committee on Nuclear and Radiochemistry Workshop on High-Temperature and Nuclear Chemical Processes in Severe Reactor Accidents; Committee on Chemical Engineering Frontiers Research Needs and Opportunities; Committee on Separation Science on Technology; Panel on Future Directions for Fundamental Science in Fossil Energy Research; Committee for Handling and Disposal of Biohazards in the Laboratory (BIL); Advisory Panels to the AFSOR Chemical and Atmospheric Sciences Directorate; US National Committee for Pure and Applied Chemistry; US National Committee for Biochemistry; US National Committee for Crystallography

  15. Chemical bridges for enhancing hydrogen storage by spillover and methods for forming the same

    Science.gov (United States)

    Yang, Ralph T.; Li, Yingwei; Qi, Gongshin; Lachawiec, Jr., Anthony J.

    2012-12-25

    A composition for hydrogen storage includes a source of hydrogen atoms, a receptor, and a chemical bridge formed between the source and the receptor. The chemical bridge is formed from a precursor material. The receptor is adapted to receive hydrogen spillover from the source.

  16. Low-Cost Precursors to Novel Hydrogen Storage Materials

    International Nuclear Information System (INIS)

    Linehan, Suzanne W.; Chin, Arthur A.; Allen, Nathan T.; Butterick, Robert; Kendall, Nathan T.; Klawiter, I. Leo; Lipiecki, Francis J.; Millar, Dean M.; Molzahn, David C.; November, Samuel J.; Jain, Puja; Nadeau, Sara; Mancroni, Scott

    2010-01-01

    From 2005 to 2010, The Dow Chemical Company (formerly Rohm and Haas Company) was a member of the Department of Energy Center of Excellence on Chemical Hydrogen Storage, which conducted research to identify and develop chemical hydrogen storage materials having the potential to achieve DOE performance targets established for on-board vehicular application. In collaboration with Center co-leads Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL), and other Center partners, Dow's efforts were directed towards defining and evaluating novel chemistries for producing chemical hydrides and processes for spent fuel regeneration. In Phase 1 of this project, emphasis was placed on sodium borohydride (NaBH 4 ), long considered a strong candidate for hydrogen storage because of its high hydrogen storage capacity, well characterized hydrogen release chemistry, safety, and functionality. Various chemical pathways for regenerating NaBH 4 from spent sodium borate solution were investigated, with the objective of meeting the 2010/2015 DOE targets of $2-3/gal gasoline equivalent at the pump ($2-3/kg H 2 ) for on-board hydrogen storage systems and an overall 60% energy efficiency. With the September 2007 No-Go decision for NaBH 4 as an on-board hydrogen storage medium, focus was shifted to ammonia borane (AB) for on-board hydrogen storage and delivery. However, NaBH 4 is a key building block to most boron-based fuels, and the ability to produce NaBH 4 in an energy-efficient, cost-effective, and environmentally sound manner is critical to the viability of AB, as well as many leading materials under consideration by the Metal Hydride Center of Excellence. Therefore, in Phase 2, research continued towards identifying and developing a single low-cost NaBH4 synthetic route for cost-efficient AB first fill, and conducting baseline cost estimates for first fill and regenerated AB using a variety of synthetic routes. This project utilized an engineering

  17. Chemical reduction of refractory oxides by atomic hydrogen

    International Nuclear Information System (INIS)

    Dooley, D.; Balooch, M.; Olander, D.R.

    1978-11-01

    The chemical reduction of UO 2 and Al 2 O 3 by atomic hydrogen was studied. Results of the UO 2 /H investigation indicates that reduction of UO 2 by atomic hydrogen proceeds by the production of water vapor and hypostoichiometric urania. Water vapor and aluminum metal are formed in the Al 2 O 3 /H system. The relative ease which UO 2 is reduced by atomic hydrogen compared with Al 2 O 3 is due to two factors. The first is related to the thermochemistry of the reactions. The second factor which favors efficient reduction of UO 2 but not of Al 2 O 3 is the oxygen diffusivity

  18. Dynamic Monte-Carlo modeling of hydrogen retention and chemical erosion from Tore Supra deposits

    International Nuclear Information System (INIS)

    Rai, A.; Schneider, R.; Warrier, M.; Roubin, P.; Martin, C.

    2009-01-01

    A multi-scale model has been developed to study the hydrogen retention [A. Rai, R. Schneider, M. Warrier, J. Nucl. Mater. 374 (2008) 304] and chemical erosion of porous graphite. To model the chemical erosion process due to thermal hydrogen ions, Kueppers cycle [J. Kueppers, Surf. Sci. Rep. 22 (1995) 249; M. Wittmann, J. Kueppers, J. Nucl. Mater. 227 (1996) 186] has been introduced. The model is applied to study hydrogen transport in deposits collected from the leading edge of neutralizers of Tore Supra. The effect of internal structure on chemical erosion is studied. The MD study [E. Salonen et al., J. Nucl. Mater. 290-293 (2001) 144] shows that the experimentally observed decrease of erosion yield at higher fluxes is due to the decrease of carbon collision cross-section at a surface due to shielding by hydrogen atom already present on the surface. Inspired by this study, a simple multi-scale model is developed to describe the flux dependence of chemical erosion. The idea is to use the local chemistry effect from the Kueppers model to calculate the hydrocarbon molecule formation process and then to find the release probability of the produced hydrocarbon based on the purely geometrical constraints. The model represents quite well the trends in experimental data.

  19. Formation of apatite on hydrogenated amorphous silicon (a-Si:H) film deposited by plasma-enhanced chemical vapor deposition

    International Nuclear Information System (INIS)

    Liu Xuanyong; Chu, Paul K.; Ding Chuanxian

    2007-01-01

    Hydrogenated amorphous silicon films were fabricated on p-type, 100 mm diameter silicon wafers by plasma-enhanced chemical vapor deposition (PECVD) using silane and hydrogen. The structure and composition of the hydrogenated amorphous silicon films were investigated using micro-Raman spectroscopy and cross-sectional transmission electron microscopy (XTEM). The hydrogenated amorphous silicon films were subsequently soaked in simulated body fluids to evaluate apatite formation. Carbonate-containing hydroxyapatite (bone-like apatite) was formed on the surface suggesting good bone conductivity. The amorphous structure and presence of surface Si-H bonds are believed to induce apatite formation on the surface of the hydrogenated amorphous silicon film. A good understanding of the surface bioactivity of silicon-based materials and means to produce a bioactive surface is important to the development of silicon-based biosensors and micro-devices that are implanted inside humans

  20. Formation of apatite on hydrogenated amorphous silicon (a-Si:H) film deposited by plasma-enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Liu Xuanyong [Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China) and Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)]. E-mail: xyliu@mail.sic.ac.cn; Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)]. E-mail: paul.chu@cityu.edu.hk; Ding Chuanxian [Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050 (China)

    2007-01-15

    Hydrogenated amorphous silicon films were fabricated on p-type, 100 mm diameter <1 0 0> silicon wafers by plasma-enhanced chemical vapor deposition (PECVD) using silane and hydrogen. The structure and composition of the hydrogenated amorphous silicon films were investigated using micro-Raman spectroscopy and cross-sectional transmission electron microscopy (XTEM). The hydrogenated amorphous silicon films were subsequently soaked in simulated body fluids to evaluate apatite formation. Carbonate-containing hydroxyapatite (bone-like apatite) was formed on the surface suggesting good bone conductivity. The amorphous structure and presence of surface Si-H bonds are believed to induce apatite formation on the surface of the hydrogenated amorphous silicon film. A good understanding of the surface bioactivity of silicon-based materials and means to produce a bioactive surface is important to the development of silicon-based biosensors and micro-devices that are implanted inside humans.

  1. Carbon dioxide management by chemical conversion to methanol: HYDROGENATION and BI-REFORMING

    International Nuclear Information System (INIS)

    Wiesberg, Igor L.; Medeiros, José Luiz de; Alves, Rita M.B.; Coutinho, Paulo L.A.; Araújo, Ofélia Q.F.

    2016-01-01

    Highlights: • Evaluation of carbon dioxide conversion to methanol by two chemical routes. • HYDROGENATION: conversion via catalytic hydrogenation at high pressure. • BI-REFORMING: conversion via syngas from bi-reforming of natural gas. • HYDROGENATION is viable for hydrogen price inferior to 1000 US$/t. • BI-REFORMING is unable to avoid emissions; viable only if gas price is very low. - Abstract: Chemical conversion of carbon dioxide to methanol has the potential to address two relevant sustainability issues: economically feasible replacement of fossil raw materials and avoidance of greenhouse gas emissions. However, chemical stability of carbon dioxide is a challenging impediment to conversion requiring severe reaction conditions at the expense of increased energy input, therefore adding capital, operation and environmental costs, which could result in partial or total override of its potential sustainability as feedstock to the chemical and energy industries. This work investigates two innovative chemical destinations of carbon dioxide to methanol, namely a direct conversion through carbon dioxide hydrogenation (HYDROGENATION), and an indirect via carbon dioxide conversion to syngas through bi-reforming (BI-REFORMING). Process simulation is used to obtain mass and energy balances needed to support assessment of economic and environmental performance. A business scenario is considered where an industrial source of nearly pure carbon dioxide exists and an investment decision for utilization of carbon dioxide is faced. Due to uncertainties in prices of the raw materials, hydrogen (HYDROGENATION) and natural gas (BI-REFORMING), the decision procedure includes the definition of price thresholds to reach profitability. Sensitivity analyses are performed varying costs with greater uncertainty, i.e., carbon dioxide and methanol, and recalculating maximum allowable prices of raw materials. The analyses show that in a Brazilian scenario, BI-REFORMING is unlikely

  2. 76 FR 69136 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting

    Science.gov (United States)

    2011-11-08

    ... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting AGENCY: Environmental Protection Agency (EPA). ACTION: Lifting of Administrative Stay for Hydrogen Sulfide; Correction. SUMMARY: The... Administrative Stay of the reporting requirements for hydrogen sulfide. The Office of the Federal Register...

  3. 75 FR 19319 - Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting; Extension of Comment...

    Science.gov (United States)

    2010-04-14

    ... Hydrogen Sulfide; Community Right-to-Know Toxic Chemical Release Reporting; Extension of Comment Period... reporting requirements for hydrogen sulfide (Chemical Abstracts Service Number (CAS No.) 7783-06-4) (75 FR... may be potentially affected by this action if you manufacture, process, or otherwise use hydrogen...

  4. Informing hazardous zones for on-board maritime hydrogen liquid and gas systems

    Energy Technology Data Exchange (ETDEWEB)

    Blaylock, Myra L. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Pratt, Joseph William [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Bran Anleu, Gabriela A. [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Proctor, Camron [Sandia National Lab. (SNL-CA), Livermore, CA (United States)

    2018-01-01

    The significantly higher buoyancy of hydrogen compared to natural gas means that hazardous zones defined in the IGF code may be inaccurate if applied to hydrogen. This could place undue burden on ship design or could lead to situations that are unknowingly unsafe. We present dispersion analyses to examine three vessel case studies: (1) abnormal external vents of full blowdown of a liquid hydrogen tank due to a failed relief device in still air and with crosswind; (2) vents due to naturally-occurring boil-off of liquid within the tank; and (3) a leak from the pipes leading into the fuel cell room. The size of the hydrogen plumes resulting from a blowdown of the tank depend greatly on the wind conditions. It was also found that for normal operations releasing a small amount of "boil- off" gas to regulate the pressure in the tank does not create flammable concentrations.

  5. Low-Cost Precursors to Novel Hydrogen Storage Materials

    Energy Technology Data Exchange (ETDEWEB)

    Suzanne W. Linehan; Arthur A. Chin; Nathan T. Allen; Robert Butterick; Nathan T. Kendall; I. Leo Klawiter; Francis J. Lipiecki; Dean M. Millar; David C. Molzahn; Samuel J. November; Puja Jain; Sara Nadeau; Scott Mancroni

    2010-12-31

    From 2005 to 2010, The Dow Chemical Company (formerly Rohm and Haas Company) was a member of the Department of Energy Center of Excellence on Chemical Hydrogen Storage, which conducted research to identify and develop chemical hydrogen storage materials having the potential to achieve DOE performance targets established for on-board vehicular application. In collaboration with Center co-leads Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL), and other Center partners, Dow's efforts were directed towards defining and evaluating novel chemistries for producing chemical hydrides and processes for spent fuel regeneration. In Phase 1 of this project, emphasis was placed on sodium borohydride (NaBH{sub 4}), long considered a strong candidate for hydrogen storage because of its high hydrogen storage capacity, well characterized hydrogen release chemistry, safety, and functionality. Various chemical pathways for regenerating NaBH{sub 4} from spent sodium borate solution were investigated, with the objective of meeting the 2010/2015 DOE targets of $2-3/gal gasoline equivalent at the pump ($2-3/kg H{sub 2}) for on-board hydrogen storage systems and an overall 60% energy efficiency. With the September 2007 No-Go decision for NaBH{sub 4} as an on-board hydrogen storage medium, focus was shifted to ammonia borane (AB) for on-board hydrogen storage and delivery. However, NaBH{sub 4} is a key building block to most boron-based fuels, and the ability to produce NaBH{sub 4} in an energy-efficient, cost-effective, and environmentally sound manner is critical to the viability of AB, as well as many leading materials under consideration by the Metal Hydride Center of Excellence. Therefore, in Phase 2, research continued towards identifying and developing a single low-cost NaBH4 synthetic route for cost-efficient AB first fill, and conducting baseline cost estimates for first fill and regenerated AB using a variety of synthetic routes. This

  6. Design, Fabrication and Prototype testing of a Chip Integrated Micro PEM Fuel Cell Accumulator combined On-Board Range Extender

    International Nuclear Information System (INIS)

    Balakrishnan, A; Mueller, C; Reinecke, H

    2014-01-01

    In this work we present the design, fabrication and prototype testing of Chip Integrated Micro PEM Fuel Cell Accumulator (CIμ-PFCA) combined On-Board Range Extender (O-BRE). CIμ-PFCA is silicon based micro-PEM fuel cell system with an integrated hydrogen storage feature (palladium metal hydride), the run time of CIμ-PFCA is dependent on the stored hydrogen, and in order to extend its run time an O-BRE is realized (catalytic hydrolysis of chemical hydride, NaBH 4 . Combining the CIμ-PFCA and O-BRE on a system level have few important design requirements to be considered; hydrogen regulation, gas -liquid separator between the CIμ-PFCA and the O-RE. The usage of traditional techniques to regulate hydrogen (tubes), gas-liquid phase membranes (porous membrane separators) are less desirable in the micro domain, due to its space constraint. Our approach is to use a passive hydrogen regulation and gas-liquid phase separation concept; to use palladium membrane. Palladium regulates hydrogen by concentration diffusion, and its property to selectively adsorb only hydrogen is used as a passive gas-liquid phase separator. Proof of concept is shown by realizing a prototype system. The system is an assembly of CIμ-PFCA, palladium membrane and the O-BRE. The CIμ-PFCA consist of 2 individually processed silicon chips, copper supported palladium membrane realized by electroplating followed by high temperature annealing process under inter atmosphere and the O-BRE is realized out of a polymer substrate by micromilling process with platinum coated structures, which functions as a catalyst for the hydrolysis of NaBH 4 . The functionality of the assembled prototype system is demonstrated by the measuring a unit cell (area 1 mm 2 ) when driven by the catalytic hydrolysis of chemical hydride (NaBH 4 and the prototype system shows run time more than 15 hours

  7. The influence of hydrogen on the chemical, mechanical, optical/electronic, and electrical transport properties of amorphous hydrogenated boron carbide

    International Nuclear Information System (INIS)

    Nordell, Bradley J.; Karki, Sudarshan; Nguyen, Thuong D.; Rulis, Paul; Caruso, A. N.; Paquette, Michelle M.; Purohit, Sudhaunshu S.; Li, Han; King, Sean W.; Dutta, Dhanadeep; Gidley, David; Lanford, William A.

    2015-01-01

    Because of its high electrical resistivity, low dielectric constant (κ), high thermal neutron capture cross section, and robust chemical, thermal, and mechanical properties, amorphous hydrogenated boron carbide (a-B x C:H y ) has garnered interest as a material for low-κ dielectric and solid-state neutron detection applications. Herein, we investigate the relationships between chemical structure (atomic concentration B, C, H, and O), physical/mechanical properties (density, porosity, hardness, and Young's modulus), electronic structure [band gap, Urbach energy (E U ), and Tauc parameter (B 1/2 )], optical/dielectric properties (frequency-dependent dielectric constant), and electrical transport properties (resistivity and leakage current) through the analysis of a large series of a-B x C:H y thin films grown by plasma-enhanced chemical vapor deposition from ortho-carborane. The resulting films exhibit a wide range of properties including H concentration from 10% to 45%, density from 0.9 to 2.3 g/cm 3 , Young's modulus from 10 to 340 GPa, band gap from 1.7 to 3.8 eV, Urbach energy from 0.1 to 0.7 eV, dielectric constant from 3.1 to 7.6, and electrical resistivity from 10 10 to 10 15 Ω cm. Hydrogen concentration is found to correlate directly with thin-film density, and both are used to map and explain the other material properties. Hardness and Young's modulus exhibit a direct power law relationship with density above ∼1.3 g/cm 3 (or below ∼35% H), below which they plateau, providing evidence for a rigidity percolation threshold. An increase in band gap and decrease in dielectric constant with increasing H concentration are explained by a decrease in network connectivity as well as mass/electron density. An increase in disorder, as measured by the parameters E U and B 1/2 , with increasing H concentration is explained by the release of strain in the network and associated decrease in structural disorder. All of these correlations in a

  8. Influence of density on radiation-chemical yield of molecular hydrogen formed at radiolysis of aqueous solution of NaOH

    International Nuclear Information System (INIS)

    Jafarov, Y.D.; Hajiyeva, S.R.; Ramazanova, N.K.; Aliyev, S.M.; Alasgarov, A.M.

    2014-01-01

    Full text : In atom and nuclear energy the specialists knowledge about radiation-chemical yield of the initial products formed under the influence of ionizing rays on water is of great importance from the point of security. The radiation-chemical yields of molecular hydrogen have been defined according to the graph and the obtained results

  9. Influence of hydrogen on chemical vapour synthesis of different ...

    Indian Academy of Sciences (India)

    ... different growth conditions. The role of hydrogen on the surface passivation behaviour of the Ni catalyst and its correlative effect on the growth of carbon nanostructures is analysed. This direct approach can, in principle, be used to synthesize different types of carbon nanostructures by tailoring the hydrogen concentration.

  10. Quantification of chemical contaminants in the paper and board fractions of municipal solid waste

    DEFF Research Database (Denmark)

    Pivnenko, Kostyantyn; Olsson, Mikael Emil; Götze, Ramona

    2016-01-01

    on the production technology or the potential end-use of the material. Paper has been previously shown to potentially contain a large variety of chemicals. Quantitative data on the presence of chemicals in paper are necessary for appropriate waste paper management, including the recycling and re-processing of paper......Chemicals are used in materials as additives in order to improve the performance of the material or the production process itself. The presence of these chemicals in recyclable waste materials may potentially affect the recyclability of the materials. The addition of chemicals may vary depending....... However, a lack of quantitative data on the presence of chemicals in paper is evident in the literature. The aim of the present work is to quantify the presence of selected chemicals in waste paper derived from households. Samples of paper and board were collected from Danish households, including both...

  11. Fuel cell power on board a yacht - the gat option for boating and yachting

    Energy Technology Data Exchange (ETDEWEB)

    Rohland, B.; Schuldzig, H.G.; Adolf, F. [Gesellschaft fuer Angewandte Technik mbH Greifswald, Greifswald (Germany)

    2001-07-01

    Today the electric power on board of a yacht is provided by 12 V / 60-150 Ah batteries. The storage capacity of 0.7 - 1.8 kWh is too low for long term cruising without loading by the alternator. A higher storage of more than 5 kWh has Fuel Cells, powered by hydrogen or better by methanol. At first we construct a stand alone PEMFC-facility for on board production of 12 V DC power of 250 W{sub e1}, which was let operated by Hydrogen from a Ni-Hydridcylinder of 2.3 l volume. GAT has constructed a facility for on board application of a methanol-powered PEM-Fuel Cell with a storage capacity of more than 5 kWh and a peak power of 200 W{sub e1}. Some technical data of the GAT-PEMFC-apparatus and the schedule of the first field tests would be presents. (orig.)

  12. Recycling of chemical hydrogen storage materials

    International Nuclear Information System (INIS)

    Lo, C.F.; Davis, B.R.; Karan, K.

    2004-01-01

    'Full text:' Light weight chemical hydrides such as sodium borohydride (NaBH4) and lithium borohydride (LiBH4) are promising hydrogen storage materials. They offer several advantages including high volumetric storage density, safe storage, practical storage and operating condition, controlled and rapid hydrogen release kinetics in alkaline aqueous media in the presence of catalysts. In addition, borate or borax, the reaction by-product, is environmentally friendly and can be directly disposed or recycled. One technical barrier for utilizing borohydrides as hydrogen storage material is their high production cost. Sodium borohydride currently costs $90 per kg while lithium borohydride costs $8000 per kg. For commercialization, new and improved technology to manufacture borohydrides must be developed - preferably by recycling borates. We are investigating different inorganic recycling routes for regenerating borohydrides from borates. In this paper, the results of a chlorination-based recycling route, incorporating multi-step reactions, will be discussed. Experiments were conducted to establish the efficiency of various steps of the selected regeneration process. The yields of desired products as a function of reaction temperature and composition were obtained from multi-phase batch reactor. Separation efficiency of desired product was also determined. The results obtained so far appear to be promising. (author)

  13. Hydrogen plasma enhanced alignment on CNT-STM tips grown by liquid catalyst-assisted microwave plasma-enhanced chemical vapor deposition

    International Nuclear Information System (INIS)

    Tung, Fa-Kuei; Yoshimura, Masamichi; Ueda, Kazuyuki; Ohira, Yutaka; Tanji, Takayoshi

    2008-01-01

    Carbon nanotubes are grown directly on a scanning tunneling microscopy tip by liquid catalyst-assisted microwave-enhanced chemical vapor deposition, and effects of hydrogen plasma treatment on the tip have been investigated in detail by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and Raman spectroscopy. The unaligned CNTs on the as-grown tip apex have been realigned and reshaped by subsequent hydrogen plasma treatment. The diameter of CNTs is enlarged mainly due to amorphous layers being re-sputtered over their outer shells

  14. Chemical Hydrogen Storage Using Polyhedral Borane Anions and Aluminum-Ammonia-Borane Complexes

    Energy Technology Data Exchange (ETDEWEB)

    Hawthorne, M. Frederick; Jalisatgi, Satish S.; Safronov, Alexander V.; Lee, Han Beak; Wu, Jianguo

    2010-10-01

    Phase 1. Hydrolysis of borohydride compounds offer the potential for significant hydrogen storage capacity, but most work to date has focused on one particular anion, BH4-, which requires high pH for stability. Other borohydride compounds, in particular polyhedral borane anions offer comparable hydrogen storage capacity without requiring high pH media and their long term thermal and hydrolytic stability coupled with non-toxic nature make them a very attractive alternative to NaBH4. The University of Missouri project provided the overall program focal point for the investigation of catalytic hydrolysis of polyhedral borane anions for hydrogen release. Due to their inherent stability, a transition metal catalyst was necessary for the hydrolysis of polyhedral borane anions. Transition metal ions such as cobalt, nickel, palladium and rhodium were investigated for their catalytic activity in the hydrolysis of nido-KB11H14, closo-K2B10H10, and closo-K2B12H12. The rate of hydrolysis follows first-order kinetics with respect to the concentration of the polyhedral borane anion and surface area of the rhodium catalyst. The rate of hydrolysis depends upon a) choice of polyhedral borane anion, c) concentration of polyhedral borane anion, d) surface area of the rhodium catalyst and e) temperature of the reaction. In all cases the yield of hydrogen was 100% which corresponds to ~7 wt% of hydrogen (based on material wt%). Phase 2. The phase 2 of program at the University of Missouri was focused upon developing aluminum ammonia-boranes (Al-AB) as chemical hydrogen storage materials, specifically their synthesis and studies of their dehydrogenation. The ammonia borane molecule (AB) is a demonstrated source of chemically stored hydrogen (19.6 wt%) which meets DOE performance parameters except for its regeneration from spent AB and elemental hydrogen. The presence of an aluminum center bonded to multiple AB residues might combine the efficiency of AB dehydrogenation with an aluminum

  15. Hydrogen system (hydrogen fuels feasibility)

    International Nuclear Information System (INIS)

    Guarna, S.

    1991-07-01

    This feasibility study on the production and use of hydrogen fuels for industry and domestic purposes includes the following aspects: physical and chemical properties of hydrogen; production methods steam reforming of natural gas, hydrolysis of water; liquid and gaseous hydrogen transportation and storage (hydrogen-hydride technology); environmental impacts, safety and economics of hydrogen fuel cells for power generation and hydrogen automotive fuels; relevant international research programs

  16. Chemical Bonding States of TiC Films before and after Hydrogen Ion Irradiation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    TiC films deposited by rf magnetron sputtering followed by Ar+ ion bombardment were irradiated with a hydrogen ion beam. X-ray photoelectron spectroscopy (XPS) was used for characterization of the chemical bonding states of C and Ti elements of the TiC films before and after hydrogen ion irradiation, in order to understand the effect of hydrogen ion irradiation on the films and to study the mechanism of hydrogen resistance of TiC films. Conclusions can be drawn that ion bombardment at moderate energy can cause preferential physical sputtering of carbon atoms from the surface of low atomic number (Z) material. This means that ion beam bombardment leads to the formation of a non-stoichiometric composition of TiC on the surface.TiC films prepared by ion beam mixing have the more excellent characteristic of hydrogen resistance. One important cause, in addition to TiC itself, is that there are many vacant sites in TiC created by ion beam mixing.These defects can easily trap hydrogen and effectively enhance the effect of hydrogen resistance.

  17. Development of an on-board H2 storage and recovery system based on lithium borohydride.

    Science.gov (United States)

    2014-02-28

    Alkali metal borohydrides based on sodium and lithium, NaBH4 and LiBH4, have been evaluated as a potential hydrogen storage and recovery system for on-board vehicle use. The borohydride salts could be dissolved in water, followed by a hydrolytic reac...

  18. Organic chemical hydrides as storage medium of hydrogen on the basis of superheated liquid-film concept

    International Nuclear Information System (INIS)

    Shinya Hodoshima; Atsushi Shono; Kazumi Satoh; Yasukazu Saito

    2006-01-01

    A catalysis pair of tetralin dehydrogenation / naphthalene hydrogenation has been proposed in the present paper as an organic chemical hydride for operating stationary fuel cells. Catalytic naphthalene hydrogenation, having been commercialized since the 1940's, proceeds to generate decalin via tetralin as an intermediate. The storage capacities of tetralin (3.0 wt%, 28.2 kg-H 2 / m 3 ) are lower than decalin (7.3 wt%, 64.8 kg-H 2 / m 3 ) but both tetralin dehydrogenation and naphthalene hydrogenation are much faster than the decalin / naphthalene pair. Moreover, existing infrastructures, e.g., gas station and tank lorry, are available for storage, transportation and supply of hydrogen. As for the stationary fuel cells with large space for hydrogen storage, tetralin as a hydrogen carrier is superior to decalin in terms of fast hydrogen supply. Rapid hydrogen supply from tetralin under mild conditions was only accomplished with the carbon supported metal catalysts in the 'superheated liquid-film states' under reactive distillation conditions. In contrast to the ordinary suspended states, the catalyst layer superheated in the liquid-film state gave high catalytic performances at around 250 C. As a result, serious coke formation over the catalyst surface and excessive exergy consumption were prevented simultaneously. (authors)

  19. Chemical-clathrate hybrid hydrogen storage: storage in both guest and host.

    Science.gov (United States)

    Strobel, Timothy A; Kim, Yongkwan; Andrews, Gary S; Ferrell, Jack R; Koh, Carolyn A; Herring, Andrew M; Sloan, E Dendy

    2008-11-12

    Hydrogen storage from two independent sources of the same material represents a novel approach to the hydrogen storage problem, yielding storage capacities greater than either of the individual constituents. Here we report a novel hydrogen storage scheme in which recoverable hydrogen is stored molecularly within clathrate cavities as well as chemically in the clathrate host material. X-ray diffraction and Raman spectroscopic measurements confirm the formation of beta-hydroquinone (beta-HQ) clathrate with molecular hydrogen. Hydrogen within the beta-HQ clathrate vibrates at considerably lower frequency than hydrogen in the free gaseous phase and rotates nondegenerately with splitting comparable to the rotational constant. Compared with water-based clathrate hydrate phases, the beta-HQ+H2 clathrate shows remarkable stability over a range of p-T conditions. Subsequent to clathrate decomposition, the host HQ was used to directly power a PEM fuel cell. With one H2 molecule per cavity, 0.61 wt % hydrogen may be stored in the beta-HQ clathrate cavities. When this amount is combined with complete dehydrogenation of the host hydroxyl hydrogens, the maximum hydrogen storage capacity increases nearly 300% to 2.43 wt %.

  20. Tailoring Thermodynamics and Kinetics for Hydrogen Storage in Complex Hydrides towards Applications.

    Science.gov (United States)

    Liu, Yongfeng; Yang, Yaxiong; Gao, Mingxia; Pan, Hongge

    2016-02-01

    Solid-state hydrogen storage using various materials is expected to provide the ultimate solution for safe and efficient on-board storage. Complex hydrides have attracted increasing attention over the past two decades due to their high gravimetric and volumetric hydrogen densities. In this account, we review studies from our lab on tailoring the thermodynamics and kinetics for hydrogen storage in complex hydrides, including metal alanates, borohydrides and amides. By changing the material composition and structure, developing feasible preparation methods, doping high-performance catalysts, optimizing multifunctional additives, creating nanostructures and understanding the interaction mechanisms with hydrogen, the operating temperatures for hydrogen storage in metal amides, alanates and borohydrides are remarkably reduced. This temperature reduction is associated with enhanced reaction kinetics and improved reversibility. The examples discussed in this review are expected to provide new inspiration for the development of complex hydrides with high hydrogen capacity and appropriate thermodynamics and kinetics for hydrogen storage. © 2015 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Safety evaluation of food contact paper and board using chemical tests and in vitro bioassays: role of known and unknown substances.

    Science.gov (United States)

    Honkalampi-Hämäläinen, U; Bradley, E L; Castle, L; Severin, I; Dahbi, L; Dahlman, O; Lhuguenot, J-C; Andersson, M A; Hakulinen, P; Hoornstra, D; Mäki-Paakkanen, J; Salkinoja-Salonen, M; Turco, L; Stammati, A; Zucco, F; Weber, A; von Wright, A

    2010-03-01

    In vitro toxicological tests have been proposed as an approach to complement the chemical safety assessment of food contact materials, particularly those with a complex or unknown chemical composition such as paper and board. Among the concerns raised regarding the applicability of in vitro tests are the effects of interference of the extractables on the outcome of the cytotoxicity and genotoxicity tests applied and the role of known compounds present in chemically complex materials, such as paper and board, either as constituents or contaminants. To answer these questions, a series of experiments were performed to assess the role of natural substances (wood extracts, resin acids), some additives (diisopropylnaphthalene, phthalates, acrylamide, fluorescent whitening agents) and contaminants (2,4-diaminotoluene, benzo[a]pyrene) in the toxicological profile of paper and board. These substances were individually tested or used to spike actual paper and board extracts. The toxic concentrations of diisopropylnaphthalenes and phthalates were compared with those actually detected in paper and board extracts showing conspicuous toxicity. According to the results of the spiking experiments, the extracts did not affect the toxicity of tested chemicals nor was there any significant metabolic interference in the cases where two compounds were used in tests involving xenobiotic metabolism by the target cells. While the identified substances apparently have a role in the cytotoxicity of some of the project samples, their presence does not explain the total toxicological profile of the extracts. In conclusion, in vitro toxicological testing can have a role in the safety assessment of chemically complex materials in detecting potentially harmful activities not predictable by chemical analysis alone.

  2. Research and development on chemical reactors made of industrial structural materials and hydriodic acid concentration technique for thermochemical hydrogen production IS process

    International Nuclear Information System (INIS)

    Kubo, Shinji; Iwatsuki, Jin; Takegami, Hiroaki; Kasahara, Seiji; Tanaka, Nobuyuki; Noguchi, Hiroki; Kamiji, Yu; Onuki, Kaoru

    2015-10-01

    Japan Atomic Energy Agency has been conducting a study on IS process for thermochemical hydrogen production in order to develop massive hydrogen production technology for hydrogen society. Integrity of the chemical reactors and concentration technology of hydrogen iodide in HIx solution were studied. In the former study, the chemical reactors were trial-fabricated using industrial materials. A test of 30 times of thermal cycle test under circulating condition of the Bunsen reaction solution showed integrity of the Bunsen reactor made of fluororesin lined steel. Also, 100 hours of reaction tests showed integrity of the sulfuric acid decomposer made of silicon carbide and of the hydrogen iodide decomposer made of Hastelloy C-276. In the latter study, concerning electro-electrodialysis using cation-exchange membrane, sulfuric acid in the anolyte had little influence on the concentration performance. These results suggest the purification system of HIx solution can be simplified. Based on the Nernst-Planck equation and the Smoluchowski equation, proton transport number, water permeance, and IR drop of the cation exchange membrane were formulated. The derived equations enable quantitative estimation for the performance indexes of Nafion ® membrane and, also, of ETFE-St membranes made by radiation-induced graft polymerization method. (author)

  3. Hydrogen fluoride (HF) substance flow analysis for safe and sustainable chemical industry.

    Science.gov (United States)

    Kim, Junbeum; Hwang, Yongwoo; Yoo, Mijin; Chen, Sha; Lee, Ik-Mo

    2017-11-01

    In this study, the chemical substance flow of hydrogen fluoride (hydrofluoric acid, HF) in domestic chemical industries in 2014 was analyzed in order to provide a basic material and information for the establishment of organized management system to ensure safety during HF applications. A total of 44,751 tons of HF was made by four domestic companies (in 2014); import amount was 95,984 tons in 2014 while 21,579 tons of HF was imported in 2005. The export amount of HF was 2180 tons, of which 2074 ton (China, 1422 tons, U.S. 524 tons, and Malaysia, 128 tons) was exported for the manufacturing of semiconductors. Based on the export and import amounts, it can be inferred that HF was used for manufacturing semiconductors. The industries applications of 161,123 tons of HF were as follows: manufacturing of basic inorganic chemical substance (27,937 tons), manufacturing of other chemical products such as detergents (28,208 tons), manufacturing of flat display (24,896 tons), and manufacturing of glass container package (22,002 tons). In this study, an analysis of the chemical substance flow showed that HF was mainly used in the semiconductor industry as well as glass container manufacturing. Combined with other risk management tools and approaches in the chemical industry, the chemical substance flow analysis (CSFA) can be a useful tool and method for assessment and management. The current CSFA results provide useful information for policy making in the chemical industry and national systems. Graphical abstract Hydrogen fluoride chemical substance flows in 2014 in South Korea.

  4. HTTR workshop (workshop on hydrogen production technology)

    International Nuclear Information System (INIS)

    Shiina, Yasuaki; Takizuka, Takakazu

    2004-12-01

    Various research and development efforts have been performed to solve the global energy and environmental problems caused by large consumption of fossil fuels. Research activities on advanced hydrogen production technology by the use of nuclear heat from high temperature gas cooled reactors, for example, have been flourished in universities, research institutes and companies in many countries. The Department of HTTR Project and the Department of Advanced Nuclear Heat Technology of JAERI held the HTTR Workshop (Workshop on Hydrogen Production Technology) on July 5 and 6, 2004 to grasp the present status of R and D about the technology of HTGR and the nuclear hydrogen production in the world and to discuss about necessity of the nuclear hydrogen production and technical problems for the future development of the technology. More than 110 participants attended the Workshop including foreign participants from USA, France, Korea, Germany, Canada and United Kingdom. In the Workshop, the presentations were made on such topics as R and D programs for nuclear energy and hydrogen production technologies by thermo-chemical or other processes. Also, the possibility of the nuclear hydrogen production in the future society was discussed. The workshop showed that the R and D for the hydrogen production by the thermo-chemical process has been performed in many countries. The workshop affirmed that nuclear hydrogen production could be one of the competitive supplier of hydrogen in the future. The second HTTR Workshop will be held in the autumn next year. (author)

  5. Hydrogen storage by organic chemical hydrides and hydrogen supply to fuel cells with superheated liquid-film-type catalysis

    International Nuclear Information System (INIS)

    Hodoshima, S.; Shono, A.; Sato, K.; Saito, Y.

    2004-01-01

    Organic chemical hydrides, consisting of decalin / naphthalene and tetralin / naphthalene pairs, have been proposed as the storage medium of hydrogen for operating fuel cells in mobile and static modes. The target values in the DOE Hydrogen Plan, U.S., on storage ( 6.5 wt%, 62.0 kg-H 2 / m 3 ) are met with decalin ( 7.3 wt%, 64.8 kg-H 2 / m 3 ). In addition, existing gas stations and tank lorries are available for storage and supply of hydrogen by utilizing the decalin / naphthalene pair, suggesting that decalin is suitable for operating fuel-cell vehicles. Tetralin dehydrogenation proceeds quite rapidly, assuring a predominant power density, though its storage densities ( 3.0 wt%, 28.2 kg-H 2 / m 3 ) are relatively low. Efficient hydrogen supply from decalin or tetralin by heating at 210-280 o C was attained only with the carbon-supported nano-size metal catalysts in the 'superheated liquid-film states' under reactive distillation conditions, where coke formation over the catalyst surface was prevented. The catalyst layer superheated in the liquid-film states gave high reaction rates and conversions, minimizing the evaporation loss under boiling conditions and exergy loss in hydrogen energy systems. (author)

  6. Hydrogen Peroxide: A Key Chemical for Today's Sustainable Development.

    Science.gov (United States)

    Ciriminna, Rosaria; Albanese, Lorenzo; Meneguzzo, Francesco; Pagliaro, Mario

    2016-12-20

    The global utilization of hydrogen peroxide, a green oxidant that decomposes in water and oxygen, has gone from 0.5 million tonnes per year three decades ago to 4.5 million tonnes per year in 2014, and is still climbing. With the aim of expanding the utilization of this eminent green chemical across different industrial and civil sectors, the production and use of hydrogen peroxide as a green industrial oxidant is reviewed herein to provide an overview of the explosive growth of its industrial use over the last three decades and of the state of the art in its industrial manufacture, with important details of what determines the viability of the direct production from oxygen and hydrogen compared with the traditional auto-oxidation process. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Effect of the hydrogen flow rate on the structural and optical properties of hydrogenated amorphous silicon thin films prepared by plasma enhanced chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Ben Amor, Sana; Dimassi, Wissem; Ali Tebai, Mohamed; Ezzaouia, Hatem [Photovoltaic Laboratory Research and Technology Centre of Energy, Borj-Cedria Science and Technology Park, BP 95, 2050 Hammam-Lif (Tunisia)

    2012-10-15

    Hydrogenated amorphous silicon (a-Si:H) thin films were deposited from pure silane (SiH{sub 4}) and hydrogen (H{sub 2}) gas mixture by plasma enhanced chemical vapor deposition (PECVD) method at low temperature (400 C) using high rf power (60 W). The structural and optical properties of these films are systematically investigated as a function of the flow rate of hydrogen (F{sub H2}).The surface morphology is analyzed by atomic force microscopy (AFM). The characterization of these films with low angle X-ray diffraction revealed that the crystallite size in the films tends to decrease with increase in (F{sub H2}). The Fourier transform infrared (FTIR) spectroscopic analysis showed that at low values of (F{sub H2}),the hydrogen bonding in Si:H films shifts from di-hydrogen (Si-H{sub 2}) and (Si-H{sub 2})n complexes to the mono-hydrogen (Si-H) bonding configuration. Finally, for these optimized conditions, the deposition rate decreases with increasing (F{sub H2}). (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Confined high-pressure chemical deposition of hydrogenated amorphous silicon.

    Science.gov (United States)

    Baril, Neil F; He, Rongrui; Day, Todd D; Sparks, Justin R; Keshavarzi, Banafsheh; Krishnamurthi, Mahesh; Borhan, Ali; Gopalan, Venkatraman; Peacock, Anna C; Healy, Noel; Sazio, Pier J A; Badding, John V

    2012-01-11

    Hydrogenated amorphous silicon (a-Si:H) is one of the most technologically important semiconductors. The challenge in producing it from SiH(4) precursor is to overcome a significant kinetic barrier to decomposition at a low enough temperature to allow for hydrogen incorporation into a deposited film. The use of high precursor concentrations is one possible means to increase reaction rates at low enough temperatures, but in conventional reactors such an approach produces large numbers of homogeneously nucleated particles in the gas phase, rather than the desired heterogeneous deposition on a surface. We report that deposition in confined micro-/nanoreactors overcomes this difficulty, allowing for the use of silane concentrations many orders of magnitude higher than conventionally employed while still realizing well-developed films. a-Si:H micro-/nanowires can be deposited in this way in extreme aspect ratio, small-diameter optical fiber capillary templates. The semiconductor materials deposited have ~0.5 atom% hydrogen with passivated dangling bonds and good electronic properties. They should be suitable for a wide range of photonic and electronic applications such as nonlinear optical fibers and solar cells. © 2011 American Chemical Society

  9. Reaction of Aluminum with Water to Produce Hydrogen - 2010 Update

    Energy Technology Data Exchange (ETDEWEB)

    Petrovic, John [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Thomas, George [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2011-06-01

    A Study of Issues Related to the Use of Aluminum for On-Board Vehicular Hydrogen Storage The purpose of this White Paper is to describe and evaluate the potential of aluminum-water reactions for the production of hydrogen for on-board hydrogen-powered vehicle applications. Although the concept of reacting aluminum metal with water to produce hydrogen is not new, there have been a number of recent claims that such aluminum-water reactions might be employed to power fuel cell devices for portable applications such as emergency generators and laptop computers, and might even be considered for possible use as the hydrogen source for fuel cell-powered vehicles.

  10. Impact of hydrogen dilution on optical properties of intrinsic hydrogenated amorphous silicon films prepared by high density plasma chemical vapor deposition for solar cell applications

    Science.gov (United States)

    Chen, Huai-Yi; Lee, Yao-Jen; Chang, Chien-Pin; Koo, Horng-Show; Lai, Chiung-Hui

    2013-01-01

    P-i-n single-junction hydrogenated amorphous silicon (a-Si:H) thin film solar cells were successfully fabricated in this study on a glass substrate by high density plasma chemical vapor deposition (HDP-CVD) at low power of 50 W, low temperature of 200°C and various hydrogen dilution ratios (R). The open circuit voltage (Voc ), short circuit current density (Jsc ), fill factor (FF) and conversion efficiency (η) of the solar cell as well as the refractive index (n) and absorption coefficient (α) of the i-layer at 600 nm wavelength rise with increasing R until an abrupt drop at high hydrogen dilution, i.e. R > 0.95. However, the optical energy bandgap (Eg ) of the i-layer decreases with the R increase. Voc and α are inversely correlated with Eg . The hydrogen content affects the i-layer and p/i interface quality of the a-Si:H thin film solar cell with an optimal value of R = 0.95, which corresponds to solar cell conversion efficiency of 3.85%. The proposed a-Si:H thin film solar cell is expected to be improved in performance.

  11. Compact PEM fuel cell system combined with all-in-one hydrogen generator using chemical hydride as a hydrogen source

    International Nuclear Information System (INIS)

    Kim, Jincheol; Kim, Taegyu

    2015-01-01

    Highlights: • Compact fuel cell system was developed for a portable power generator. • Novel concept using an all-in-one reactor for hydrogen generation was proposed. • Catalytic reactor, hydrogen chamber and separator were combined in a volume. • The system can be used to drive fuel cell-powered unmanned autonomous systems. - Abstract: Compact fuel cell system was developed for a portable power generator. The power generator features a polymer electrolyte membrane fuel cell (PEMFC) using a chemical hydride as a hydrogen source. The hydrogen generator extracted hydrogen using a catalytic hydrolysis from a sodium borohydride alkaline solution. A novel concept using an all-in-one reactor was proposed in which a catalyst, hydrogen chamber and byproduct separator were combined in a volume. In addition, the reactor as well as a pump, cooling fans, valves and controller was integrated in a single module. A 100 W PEMFC stack was connected with the hydrogen generator and was evaluated at various load conditions. It was verified that the stable hydrogen supply was achieved and the developed system can be used to drive fuel cell-powered unmanned autonomous systems.

  12. Decontamination of adsorbed chemical warfare agents on activated carbon using hydrogen peroxide solutions.

    Science.gov (United States)

    Osovsky, Ruth; Kaplan, Doron; Nir, Ido; Rotter, Hadar; Elisha, Shmuel; Columbus, Ishay

    2014-09-16

    Mild treatment with hydrogen peroxide solutions (3-30%) efficiently decomposes adsorbed chemical warfare agents (CWAs) on microporous activated carbons used in protective garments and air filters. Better than 95% decomposition of adsorbed sulfur mustard (HD), sarin, and VX was achieved at ambient temperatures within 1-24 h, depending on the H2O2 concentration. HD was oxidized to the nontoxic HD-sulfoxide. The nerve agents were perhydrolyzed to the respective nontoxic methylphosphonic acids. The relative rapidity of the oxidation and perhydrolysis under these conditions is attributed to the microenvironment of the micropores. Apparently, the reactions are favored due to basic sites on the carbon surface. Our findings suggest a potential environmentally friendly route for decontamination of adsorbed CWAs, using H2O2 without the need of cosolvents or activators.

  13. Development program of hydrogen production by thermo-chemical water splitting is process

    International Nuclear Information System (INIS)

    Ryutaro Hino

    2005-01-01

    The Japan Atomic Energy Research Institute (JAERI) has been conducting R and D on the HTGR and also on thermo-chemical water splitting hydrogen production by using a iodine-sulfur cycle (IS process) in the HTTR project. The continuous hydrogen production for one week was demonstrated with a bench-scale test apparatus made of glass, and the hydrogen production rare was about 31 NL/h. Based on the test results and know-how obtained through the bench-scale test, a pilot test plant, which has a hydrogen production performance of 30 Nm 3 /h and will be operated under the high pressure up to 2 MPa, is being designed conceptually as the next step of the IS process development aiming to realize a future nuclear hydrogen production coupled with the HTGR. In this paper, we will introduce one-week continuous hydrogen production conducted with the bench-scale test apparatus and the pilot test program including R and D and an analytical system necessary for designing the pilot test plant. MW. Figure 1 shows an overview of the HTTR-IS plant. In this paper, we will introduce latest test results obtained with the bench-scale test apparatus and concepts of key components of the IS process, a sulfuric acid (H 2 SO 4 ) and a sulfur trioxide (SO 3 ) decomposers working under high-temperature corrosive circumstance, are also introduced as well as relating R and D and an analytical system for the pilot plant design. (authors)

  14. Biasing hydrogen bond donating host systems towards chemical warfare agent recognition.

    Science.gov (United States)

    Hiscock, Jennifer R; Wells, Neil J; Ede, Jayne A; Gale, Philip A; Sambrook, Mark R

    2016-10-12

    A series of neutral ditopic and negatively charged, monotopic host molecules have been evaluated for their ability to bind chloride and dihydrogen phosphate anions, and neutral organophosphorus species dimethyl methylphosphonate (DMMP), pinacolyl methylphosphonate (PMP) and the chemical warfare agent (CWA) pinacolyl methylphosphonofluoridate (GD, soman) in organic solvent via hydrogen bonding. Urea, thiourea and boronic acid groups are shown to bind anions and neutral guests through the formation of hydrogen bonds, with the urea and thiourea groups typically exhibiting higher affinity interactions. The introduction of a negative charge on the host structure is shown to decrease anion affinity, whilst still allowing for high stability host-GD complex formation. Importantly, the affinity of the host for the neutral CWA GD is greater than for anionic guests, thus demonstrating the potential for selectivity reversal based on charge repulsion.

  15. Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - final report

    International Nuclear Information System (INIS)

    Gerton, R.E.

    1997-01-01

    On May 14, 1997, at 7:53 p.m. (PDT), a chemical explosion occur-red in Tank A- 109 in Room 40 of the Plutonium Reclamation Facility (Facility) located in the 200 West Area of the Hanford Site, approximately 30 miles north of Richland, Washington. The inactive processing Facility is part of the Plutonium Finishing Plant (PFP). On May 16, 1997, Lloyd L. Piper, Deputy Manager, acting for John D. Wagoner, Manager, U.S. Department of Energy (DOE), Richland Operations Office (RL), formally established an Accident Investigation Board (Board) to investigate the explosion in accordance with DOE Order 225. 1, Accident Investigations. The Board commenced its investigation on May 15, 1997, completed the investigation on July 2, 1997, and submitted its findings to the RL Manager on July 26, 1997. The scope of the Board's investigation was to review and analyze the circumstances of the events that led to the explosion; to analyze facts and to determine the causes of the accident; and to develop conclusions and judgments of need that may help prevent a recurrence of the accident. The scope also included the application of lessons learned from similar accidents within DOE. In addition to this detailed report, a companion document has also been prepared that provides a concise summary of the facts and conclusions of this report, with an emphasis on management issues (DOE/RL-97-63)

  16. Spark Discharge Generated Nanoparticles for Hydrogen Storage Applications

    NARCIS (Netherlands)

    Vons, V.A.

    2010-01-01

    One of the largest obstacles to the large scale application of hydrogen powered fuel cell vehicles is the absence of hydrogen storage methods suitable for application on-board of these vehicles. Metal hydrides are materials in which hydrogen is reversibly absorbed by one or more metals or

  17. Mechanochemical synthesis of nanostructured chemical hydrides in hydrogen alloying mills

    International Nuclear Information System (INIS)

    Wronski, Z.; Varin, R.A.; Chiu, C.; Czujko, T.; Calka, A.

    2007-01-01

    Mechanical alloying of magnesium metal powders with hydrogen in specialized hydrogen ball mills can be used as a direct route for mechanochemical synthesis of emerging chemical hydrides and hydride mixtures for advanced solid-state hydrogen storage. In the 2Mg-Fe system, we have successfully synthesized the ternary complex hydride Mg 2 FeH 6 in a mixture with nanometric Fe particles. The mixture of complex magnesium-iron hydride and nano-iron released 3-4 wt.%H 2 in a thermally programmed desorption experiment at the range 285-295 o C. Milling of the Mg-2Al powder mixture revealed a strong competition between formation of the Al(Mg) solid solution and the β-MgH 2 hydride. The former decomposes upon longer milling as the Mg atoms react with hydrogen to form the hydride phase, and drive the Al out of the solid solution. The mixture of magnesium dihydride and nano-aluminum released 2.1 wt.%H 2 in the temperature range 329-340 o C in the differential scanning calorimetry experiment. The formation of MgH 2 was suppressed in the Mg-B system; instead, a hydrogenated amorphous phase (Mg,B)H x , was formed in a mixture with nanometric MgB 2 . Annealing of the hydrogen-stabilized amorphous mixture produced crystalline MgB 2

  18. Chemical aspects of hydrogen ingress in zirconium and zircaloy pressure tubes: ageing management of Indian PHWR coolant channels - determination of hydrogen and deuterium

    International Nuclear Information System (INIS)

    Sayi, Y.S.; Shankaran, P.S.; Yadav, C.S.; Ramanjaneyulu, P.S.; Venugopal, V.; Ramakumar, K.L.; Chhapru, G.C.; Prasad, R.; Jain, H.C.; Sood, D.D.

    2009-02-01

    Pressurized heavy water reactors (PHWRs) use zirconium and zirconium based alloys as clad and coolant tubes since its beginning. The first ever zircaloy-2 pressure tube failure occurred in 1983 at Ontario Hydro's Pickering Unit 2 in Canada which necessitated a thorough examination of causes of such failure. The failure was attributed to massive hydriding at the failed spot of pressure tube. Continuous usage of zirconium alloys could result in their hydrogen and deuterium pick-up leading to hydrogen/ deuterium embrittlement. The life of the zircaloy coolant channels is dictated by hydrogen/deuterium content and hence ageing management of the pressure tubes is essential for ensuring their trouble-free usage. It is desirable to have a sound knowledge on the chemical aspects of zirconium and zirconium based alloys metallurgy, the mechanistic principles of hydrogen ingress into the pressure tubes during in reactor service, and identifying suitable analytical methodologies for precise and accurate determination of hydrogen in wafer thin sliver samples carved out from insides of pressure tubes without causing any structural damage so that it can continue to remain in service. This is desirable so that the ageing management does not result in cost-escalation. This report is divided in to three main parts. The first part deals with the chemical aspects of zirconium and zirconium based alloy metallurgy, the mechanism of hydrogen pick-up and hydride formation in zirconium matrix. The second part describes various methodologies and their limitations, available for hydrogen/deuterium determination. The third part deals in detail, about the extensive investigations carried out at Radioanalytical Chemistry Division (RACD) in Radiochemistry and Isotope Group for establishing an indigenously developed hot vacuum extraction system in combination with quadrupole mass spectrometry for precise determination of hydrogen and deuterium in wafer thin sliver sample of zircaloy. The

  19. Chemical grafting of Co9S8 onto C60 for hydrogen spillover and storage.

    Science.gov (United States)

    Han, Lu; Qin, Wei; Zhou, Jia; Jian, Jiahuang; Lu, Songtao; Wu, Xiaohong; Fan, Guohua; Gao, Peng; Liu, Boyu

    2017-04-20

    Metal modified C 60 is considered to be a potential hydrogen storage medium due to its high theoretical capacity. Research interest is growing in various hybrid inorganic compounds-C 60 . While the design and synthesis of a novel hybrid inorganic compound-C 60 is difficult to attain, it has been theorized that the atomic hydrogen could transfer from the inorganic compound to the adjacent C 60 surfaces via spillover and surface diffusion. Here, as a proof of concept experiment, we graft Co 9 S 8 onto C 60 via a facile high energy ball milling process. The Raman, XPS, XRD, TEM, HTEM and EELS measurements have been conducted to evaluate the composition and structure of the pizza-like hybrid material. In addition, the electrochemical measurements and calculated results demonstrate that the chemical "bridges" (C-S bonds) between these two materials enhance the binding strength and, hence, facilitate the hydriding reaction of C 60 during the hydrogen storage process. As a result, an increased hydrogen storage capacity of 4.03 wt% is achieved, along with a favorable cycling stability of ∼80% after 50 cycles. Excluding the direct hydrogen storage contribution from Co 9 S 8 in the hybrid paper, the hydrogen storage ability of C 60 was enhanced by 5.9× through the hydriding reaction caused by the Co 9 S 8 modifier. Based on these experimental measurements and theoretical calculations, the unique chemical structure reported here could potentially inspire other C 60 -based advanced hybrids.

  20. A study of chemical equilibrium of tri-component mixtures of hydrogen isotopes

    International Nuclear Information System (INIS)

    Cristescu, Ioana; Cristescu, I.; Peculea, M.

    1998-01-01

    In this paper we present a model for computing the equilibrium constants for chemical reactions between hydrogen's isotopes as function of temperature. The equilibrium constants were expressed with the aid of Gibbs potential and the partition function of the mixture. We assessed the partition function for hydrogen's isotopes having in view that some nuclei are fermions and other bosons. As results we plotted the values of equilibrium constants as function of temperature. Knowing these values we determined the deuterium distribution on species (for mixture H 2 -HD-D 2 ) as function of total deuterium concentration and the tritium distribution on species (for mixtures D 2 -DT-T 2 and H 2 -HT-T 2 ) as function of total tritium concentration. (authors)

  1. The impact of hydrogen and oxidizing impurities in chemical vapor deposition of graphene on copper

    Science.gov (United States)

    Choubak, Saman

    Graphene, the single-atom layer of carbon, has attracted scientists and technologists due to its outstanding physical and opto/electronic properties. The use of graphene in practical applications requires a reliable and cost-effective method to produce large area graphene films with low defects and controlled thicknesses. Direct growth of graphene using chemical vapor deposition (CVD) on copper, in which carbonaceous gaseous species react with the metal substrate in the presence of hydrogen at high temperatures (850-1100° C), led to high coverage of high quality graphene, opening up a promising future for methods of this type and a large step towards commercial realization of graphene products. The present thesis deals with the synthesis of graphene via low pressure CVD (LP-CVD) on copper catalyst using methane as the carbon precursor. The focus is mainly on the determination of the role of hydrogen and oxidizing impurities during graphene formation with an ultimate purpose: to elucidate a viable and reproducible method for the production of high quality graphene films compatible with industrial manufacturing processes. The role of molecular hydrogen in graphene CVD is explored in the first part of the thesis. Few studies claimed that molecular hydrogen etches graphene films on copper by conducting annealing experiments. On the other hand, we speculated that this graphene etching reaction is due to the presence of trace amount of oxygen in the furnace atmosphere. Thus, we took another approach and designed systematic annealing experiments to investigate the role of hydrogen in the etching reaction of graphene on copper foils. No evidence of graphene etching on copper was observed when purified ultra high purity (UHP) hydrogen was used at 825 °C and 500 mTorr. Nevertheless, graphene films exposed to the unpurified UHP hydrogen were etched due to the presence of oxidizing impurities. Our results show that hydrogen is not responsible for graphene etching reaction

  2. Thermo-chemical production of hydrogen from water by metal oxides fixed on ceramic substrates

    International Nuclear Information System (INIS)

    Roeb, M.; Monnerie, N.; Schmitz, M.; Sattler, C.; Konstandopoulos, A.G.; Agrafiotis, C.; Zaspalis, V.T.; Nalbandian, L.; Steele, A.; Stobbe, P.

    2006-01-01

    In the European project HYDROSOL a simple two-step thermo-chemical cycle process has been developed and investigated. It is based on metal oxide redox pair systems, which can split water molecules by abstracting oxygen atoms and reversibly incorporating them into their lattice. If concentrated solar radiation is used as the heat source one has a promising method in hand to produce hydrogen without any environmentally critical emissions. The basic idea is to combine a support capable of achieving high temperatures when heated by concentrated solar radiation, with a redox pair system suitable for water dissociation and at the same time for regeneration at these temperatures, so that complete operation of the whole process could be achieved by a single solar energy converter. The feasibility of the process has proven possible in a mini-plant scale using concentrated sunlight provided by the solar furnace in Cologne. Suitable redox materials as coatings and a dedicated receiver-reactor have been developed to produce hydrogen with significant conversions by repeating several subsequent water splitting and regeneration steps. In a design study a possible way of operating the process in commercial scale is demonstrated. (authors)

  3. An Integrated Photoelectrochemical-Chemical Loop for Solar-Driven Overall Splitting of Hydrogen Sulfide

    DEFF Research Database (Denmark)

    Zong, Xu; Han, Jingfeng; Seger, Brian

    2014-01-01

    Abundant and toxic hydrogen sulfide (H2S) from industry and nature has been traditionally considered a liability. However, it represents a potential resource if valuable H-2 and elemental sulfur can be simultaneously extracted through a H2S splitting reaction. Herein a photochemical-chemical loop...... simulated solar light. This new conceptual design will not only provide a possible route for using solar energy to convert H2S into valuable resources, but also sheds light on some challenging photochemical reactions such as CH4 activation and CO2 reduction.......Abundant and toxic hydrogen sulfide (H2S) from industry and nature has been traditionally considered a liability. However, it represents a potential resource if valuable H-2 and elemental sulfur can be simultaneously extracted through a H2S splitting reaction. Herein a photochemical-chemical loop...... linked by redox couples such as Fe2+/Fe3+ and I-/I-3(-) for photoelectrochemical H-2 production and H2S chemical absorption redox reactions are reported. Using functionalized Si as photoelectrodes, H2S was successfully split into elemental sulfur and H-2 with high stability and selectivity under...

  4. Analytic description of the chemical erosion of graphite by hydrogen ions

    International Nuclear Information System (INIS)

    Roth, J.; Garcia-Rosales, C.

    1996-01-01

    One main concern about the use of graphite as a plasma facing material is the enhanced erosion, under hydrogen bombardment due to hydrocarbon formation. In view of the lifetime evaluation of plasma exposed carbon components and of impurity production in present and future machines such as ITER, an analytical expression for the erosion yield by chemical sputtering for the relevant energies, temperatures and incident fluxes is of special importance. An extrapolation to fluxes and energies relevant for high density divertor plasmas has not been possible up to now on the basis of semiempirical fits to laboratory data. Starting from a short review of the existing empirical formulas, recent detailed investigations of the atomistic processes for the thermally activated hydrocarbon emission are described, which enable the formulation of an improved analytical description including the ion flux as a parameter. The chemical erosion of graphite by hydrogen bombardment results from two processes: the thermally activated hydrocarbon emission, Y therm , and a surface process at low energies and low temperatures resulting from the kinetic ejection of surface hydrocarbon complexes from collisional energy transfer, Y surf . The new analytic description can be fitted well to the existing data for ion beam erosion, and extrapolation to divertor relevant fluxes is possible. At high ion fluxes the maximum of chemical erosion is shifted to higher temperatures, where annealing of damaged structures leads to a stronger reduction of Y therm than previously estimated. There are no data on a possible flux dependence of Y surf , leaving still some uncertainty in extrapolation. (author). 46 refs, 10 figs, 1 tab

  5. Hydrogen, nitrogen and syngas enriched diesel combustion

    OpenAIRE

    Christodoulou, Fanos

    2014-01-01

    This thesis was submitted for the degree of Doctor of Philosophy and awarded by Brunel University On-board hydrogen and syngas production is considered as a transition solution from fossil fuel to hydrogen powered vehicles until problems associated with hydrogen infrastructure, distribution and storage are resolved. A hydrogen- or syngas-rich stream, which substitutes part of the main hydrocarbon fuel, can be produced by supplying diesel fuel in a fuel-reforming reactor, integrated within ...

  6. Study of hydrogenated silicene: The initialization model of hydrogenation on planar, low buckled and high buckled structures of silicene

    International Nuclear Information System (INIS)

    Syaputra, Marhamni; Wella, Sasfan Arman; Wungu, Triati Dewi Kencana; Purqon, Acep; Suprijadi

    2015-01-01

    We study the hydrogenation structures possessed by silicene i.e. planar (PL), low buckled (LB) and high buckled (HB). On those structures we found the hydrogenation process occurs with some particular notes. Hydrogen stable position on the silicene surface is determined by its initial configuration. We only considered the fully hydrogenated case with the formula unit (SiH) n for all of these structures. Physical and electronic structure shift after the process are compared with hydrogenated graphene. Moreover, we observed a chemical process in the presence of hydrogen on the PL structure by nudged elastic band (NEB) which illustrates how hydrogen has a significant impact to the force barrier of the PL that changing it from its original structure

  7. Effects of temperature and mass conservation on the typical chemical sequences of hydrogen oxidation

    Science.gov (United States)

    Nicholson, Schuyler B.; Alaghemandi, Mohammad; Green, Jason R.

    2018-01-01

    Macroscopic properties of reacting mixtures are necessary to design synthetic strategies, determine yield, and improve the energy and atom efficiency of many chemical processes. The set of time-ordered sequences of chemical species are one representation of the evolution from reactants to products. However, only a fraction of the possible sequences is typical, having the majority of the joint probability and characterizing the succession of chemical nonequilibrium states. Here, we extend a variational measure of typicality and apply it to atomistic simulations of a model for hydrogen oxidation over a range of temperatures. We demonstrate an information-theoretic methodology to identify typical sequences under the constraints of mass conservation. Including these constraints leads to an improved ability to learn the chemical sequence mechanism from experimentally accessible data. From these typical sequences, we show that two quantities defining the variational typical set of sequences—the joint entropy rate and the topological entropy rate—increase linearly with temperature. These results suggest that, away from explosion limits, data over a narrow range of thermodynamic parameters could be sufficient to extrapolate these typical features of combustion chemistry to other conditions.

  8. Development of Bi-phase sodium-oxygen-hydrogen chemical equilibrium calculation program (BISHOP) using Gibbs free energy minimization method

    International Nuclear Information System (INIS)

    Okano, Yasushi

    1999-08-01

    In order to analyze the reaction heat and compounds due to sodium combustion, the multiphase chemical equilibrium calculation program for chemical reaction among sodium, oxygen and hydrogen is developed in this study. The developed numerical program is named BISHOP; which denotes Bi-Phase, Sodium - Oxygen - Hydrogen, Chemical Equilibrium Calculation Program'. Gibbs free energy minimization method is used because of the special merits that easily add and change chemical species, and generally deal many thermochemical reaction systems in addition to constant temperature and pressure one. Three new methods are developed for solving multi-phase sodium reaction system in this study. One is to construct equation system by simplifying phase, and the other is to expand the Gibbs free energy minimization method into multi-phase system, and the last is to establish the effective searching method for the minimum value. Chemical compounds by the combustion of sodium in the air are calculated using BISHOP. The Calculated temperature and moisture conditions where sodium-oxide and hydroxide are formed qualitatively agree with the experiments. Deformation of sodium hydride is calculated by the program. The estimated result of the relationship between the deformation temperature and pressure closely agree with the well known experimental equation of Roy and Rodgers. It is concluded that BISHOP can be used for evaluated the combustion and deformation behaviors of sodium and its compounds. Hydrogen formation condition of the dump-tank room at the sodium leak event of FBR is quantitatively evaluated by BISHOP. It can be concluded that to keep the temperature of dump-tank room lower is effective method to suppress the formation of hydrogen. In case of choosing the lower inflammability limit of 4.1 mol% as the hydrogen concentration criterion, formation reaction of sodium hydride from sodium and hydrogen is facilitated below the room temperature of 800 K, and concentration of hydrogen

  9. Liquid Hydrogen Consumption During Space Shuttle Program

    Science.gov (United States)

    Partridge, Jonathan K.

    2011-01-01

    This slide presentation reviews the issue of liquid hydrogen consumption and the points of its loss in prior to the shuttle launch. It traces the movement of the fuel from the purchase to the on-board quantity and the loss that results in 54.6 of the purchased quantity being on board the Shuttle.

  10. Optimizing the Binding Energy of Hydrogen on Nanostructured Carbon Materials through Structure Control and Chemical Doping

    Energy Technology Data Exchange (ETDEWEB)

    Jie Liu

    2011-02-01

    The DOE Hydrogen Sorption Center of Excellence (HSCoE) was formed in 2005 to develop materials for hydrogen storage systems to be used in light-duty vehicles. The HSCoE and two related centers of excellence were created as follow-on activities to the DOE Office of Energy Efficiency and Renewable Energy’s (EERE’s) Hydrogen Storage Grand Challenge Solicitation issued in FY 2003. The Hydrogen Sorption Center of Excellence (HSCoE) focuses on developing high-capacity sorbents with the goal to operate at temperatures and pressures approaching ambient and be efficiently and quickly charged in the tank with minimal energy requirements and penalties to the hydrogen fuel infrastructure. The work was directed at overcoming barriers to achieving DOE system goals and identifying pathways to meet the hydrogen storage system targets. To ensure that the development activities were performed as efficiently as possible, the HSCoE formed complementary, focused development clusters based on the following four sorption-based hydrogen storage mechanisms: 1. Physisorption on high specific surface area and nominally single element materials 2. Enhanced H2 binding in Substituted/heterogeneous materials 3. Strong and/or multiple H2 binding from coordinated but electronically unsatruated metal centers 4. Weak Chemisorption/Spillover. As a member of the team, our group at Duke studied the synthesis of various carbon-based materials, including carbon nanotubes and microporous carbon materials with controlled porosity. We worked closely with other team members to study the effect of pore size on the binding energy of hydrogen to the carbon –based materials. Our initial project focus was on the synthesis and purification of small diameter, single-walled carbon nanotubes (SWNTs) with well-controlled diameters for the study of their hydrogen storage properties as a function of diameters. We developed a chemical vapor deposition method that synthesized gram quantities of carbon nanotubes with

  11. Benchmarking Hydrogen and Carbon NMR Chemical Shifts at HF, DFT, and MP2 Levels.

    Science.gov (United States)

    Flaig, Denis; Maurer, Marina; Hanni, Matti; Braunger, Katharina; Kick, Leonhard; Thubauville, Matthias; Ochsenfeld, Christian

    2014-02-11

    An extensive study of error distributions for calculating hydrogen and carbon NMR chemical shifts at Hartree-Fock (HF), density functional theory (DFT), and Møller-Plesset second-order perturbation theory (MP2) levels is presented. Our investigation employs accurate CCSD(T)/cc-pVQZ calculations for providing reference data for 48 hydrogen and 40 carbon nuclei within an extended set of chemical compounds covering a broad range of the NMR scale with high relevance to chemical applications, especially in organic chemistry. Besides the approximations of HF, a variety of DFT functionals, and conventional MP2, we also present results with respect to a spin component-scaled MP2 (GIAO-SCS-MP2) approach. For each method, the accuracy is analyzed in detail for various basis sets, allowing identification of efficient combinations of method and basis set approximations.

  12. Design Tool for Estimating Chemical Hydrogen Storage System Characteristics for Light-Duty Fuel Cell Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Kriston P.; Sprik, Sam; Tamburello, David; Thornton, Matthew

    2018-05-03

    The U.S. Department of Energy (DOE) has developed a vehicle framework model to simulate fuel cell-based light-duty vehicle operation for various hydrogen storage systems. This transient model simulates the performance of the storage system, fuel cell, and vehicle for comparison to DOE’s Technical Targets using four drive cycles/profiles. Chemical hydrogen storage models have been developed for the Framework model for both exothermic and endothermic materials. Despite the utility of such models, they require that material researchers input system design specifications that cannot be easily estimated. To address this challenge, a design tool has been developed that allows researchers to directly enter kinetic and thermodynamic chemical hydrogen storage material properties into a simple sizing module that then estimates the systems parameters required to run the storage system model. Additionally, this design tool can be used as a standalone executable file to estimate the storage system mass and volume outside of the framework model and compare it to the DOE Technical Targets. These models will be explained and exercised with existing hydrogen storage materials.

  13. Design Tool for Estimating Chemical Hydrogen Storage System Characteristics for Light-Duty Fuel Cell Vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Thornton, Matthew J [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Sprik, Samuel [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Brooks, Kriston P. [Pacific Northwest National Laboratory; Tamburello, David A. [Savannah River National Laboratory

    2018-04-07

    The U.S. Department of Energy (DOE) developed a vehicle Framework model to simulate fuel cell-based light-duty vehicle operation for various hydrogen storage systems. This transient model simulates the performance of the storage system, fuel cell, and vehicle for comparison to Technical Targets established by DOE for four drive cycles/profiles. Chemical hydrogen storage models have been developed for the Framework for both exothermic and endothermic materials. Despite the utility of such models, they require that material researchers input system design specifications that cannot be estimated easily. To address this challenge, a design tool has been developed that allows researchers to directly enter kinetic and thermodynamic chemical hydrogen storage material properties into a simple sizing module that then estimates system parameters required to run the storage system model. Additionally, the design tool can be used as a standalone executable file to estimate the storage system mass and volume outside of the Framework model. These models will be explained and exercised with the representative hydrogen storage materials exothermic ammonia borane (NH3BH3) and endothermic alane (AlH3).

  14. Proton exchange membrane fuel cells for electrical power generation on-board commercial airplanes

    International Nuclear Information System (INIS)

    Pratt, Joseph W.; Klebanoff, Leonard E.; Munoz-Ramos, Karina; Akhil, Abbas A.; Curgus, Dita B.; Schenkman, Benjamin L.

    2013-01-01

    Highlights: ► We examine proton exchange membrane fuel cells on-board commercial airplanes. ► We model the added fuel cell system’s effect on overall airplane performance. ► It is feasible to implement an on-board fuel cell system with current technology. ► Systems that maximize waste heat recovery are the best performing. ► Current PEM and H 2 storage technology results in an airplane performance penalty. -- Abstract: Deployed on a commercial airplane, proton exchange membrane (PEM) fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they could offer a performance advantage for the airplane when using today’s off-the-shelf technology. We also examine the effects of the fuel cell system on airplane performance with (1) different electrical loads, (2) different locations on the airplane, and (3) expected advances in fuel cell and hydrogen storage technologies. Through hardware analysis and thermodynamic simulation, we found that an additional fuel cell system on a commercial airplane is technically feasible using current technology. Although applied to a Boeing 787-type airplane, the method presented is applicable to other airframes as well. Recovery and on-board use of the heat and water that is generated by the fuel cell is an important method to increase the benefit of such a system. The best performance is achieved when the fuel cell is coupled to a load that utilizes the full output of the fuel cell for the entire flight. The effects of location are small and location may be better determined by other considerations such as safety and modularity. Although the PEM fuel cell generates power more efficiently than the gas turbine generators currently used, when considering the effect of the fuel cell system on the airplane’s overall performance we found that an overall

  15. Notification: FY 2012 Management Challenges and Internal Control Weaknesses for the Chemical Safety and Hazard Investigation Board

    Science.gov (United States)

    February 1, 2012. The EPA Office of Inspector General is beginning work to update our list of areas we consider to be the key management challenges confronting the Chemical Safety and Hazard Investigation Board.

  16. The hydrogen; L'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The hydrogen as an energy system represents nowadays a main challenge (in a scientific, economical and environmental point of view). The physical and chemical characteristics of hydrogen are at first given. Then, the challenges of an hydrogen economy are explained. The different possibilities of hydrogen production are described as well as the distribution systems and the different possibilities of hydrogen storage. Several fuel cells are at last presented: PEMFC, DMFC and SOFC. (O.M.)

  17. Technology status of hydrogen road vehicles. IEA technical report from the IEA Agreement of the production and utilization of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, T.A.

    1998-01-31

    The report was commissioned under the Hydrogen Implementing Agreement of the International Energy Agency (IEA) and examines the state of the art in the evolving field of hydrogen-fueled vehicles for road transport. The first phase surveys and analyzes developments since 1989, when a comprehensive review was last published. The report emphasizes the following: problems, especially backfiring, with internal combustion engines (ICEs); operational safety; hydrogen handling and on-board storage; and ongoing demonstration projects. Hydrogen vehicles are receiving much attention, especially at the research and development level. However, there has been a steady move during the past 5 years toward integral demonstrations of operable vehicles intended for public roads. Because they emit few, or no greenhouse gases, hydrogen vehicles are beginning to be taken seriously as a promising solution to the problems of urban air quality. Since the time the first draft of the report was prepared (mid-19 96), the 11th World Hydrogen Energy Conference took place in Stuttgart, Germany. This biennial conference can be regarded as a valid updating of the state of the art; therefore, the 1996 results are included in the current version. Sections of the report include: hydrogen production and distribution to urban users; on-board storage and refilling; vehicle power units and drives, and four appendices titled: 'Safety questions of hydrogen storage and use in vehicles', 'Performance of hydrogen fuel in internal production engines for road vehicles, 'Fuel cells for hydrogen vehicles', and 'Summaries of papers on hydrogen vehicles'. (refs., tabs.)

  18. Hydrogen adsorption on partially oxidised microporous carbons

    International Nuclear Information System (INIS)

    J B Parra; C O Ania; C J Duran Valle; M L Sanchez; C Otero Arean

    2005-01-01

    The search for cost effective adsorbents for large scale gas separation, storage and transport constitutes a present day strategic issue in the energy sector, propelled mainly by the potential use of hydrogen as an energy vector in a sustainable (and cleaner) energy scenario. Both, activated carbons and carbon based nano-structured materials have been proposed as potential candidates for reversible hydrogen storage in cryogenically cooled vessels. For that purpose, surface modification so as to enhance the gas solid interaction energy is desirable. We report on hydrogen adsorption on microporous (active) carbons which have been partially oxidised with nitric acid and ammonium persulfate. From the corresponding hydrogen adsorption isotherms (Fig. 1) an isosteric heat of about 3 kJ mol -1 was derived. This value is in agreement with that of about 3 to 4 kJ mol -1 obtained by quantum chemical calculations on the interaction between the hydrogen molecule and simple model systems (Fig. 2) of both, hydroxyl and carboxyl groups. Further research is in progress with a view to further increases the gas solid interaction energy. However, the values so far obtained are significantly larger than the liquefaction enthalpy of hydrogen: 0.90 kJ mol -1 ; and this is relevant to both, hydrogen separation from gas mixtures and cryogenic hydrogen storage. (authors)

  19. Hydrogen storage materials at INCDTIM Cluj - Napoca. Achievements and outlook

    International Nuclear Information System (INIS)

    Lupu, D.; Biris, A.R.; Misan, I.

    2005-01-01

    Introducing hydrogen fuel to the transportation area poses key challenges for research on hydrogen storage materials. As one of the most promising alternative fuels for transport, hydrogen offers the long-term potential for an energy system that produces near-zero emissions and can be based on renewable energy sources. The Joint Research Centre (JRC), a Directorate-General of the European Commission fosters research for safe methods for storing hydrogen, for use in fuel cells or modified combustion engines in cars and other road vehicles. Hydrogen storage materials focused, in the last 30 years, the attention of the research programs in the many countries. Due to the fast development of the fuel cell technologies, the subject is much more stringent now. For mobile applications to fuel cell powered vehicles, on-board storage materials with hydrogen absorption/desorption capacities of at least 6.5%H are needed. For an efficient storage system the goal is to pack hydrogen as close as possible. Hydrogen storage implies the reduction of an enormous volume of H 2 gas (1 kg of gas has a volume of 11 m 3 at ambient temperature and pressure). To reach the high volumetric and gravimetric density suitable for mobile applications, basically six reversible storage methods are known today according to A. Zuettel: 1) high-pressure gas cylinders, 2) liquid in cryogenic tanks, 3) physisorbed on a solid surface e.g. carbon-nanotubes 4) metal hydrides of the metals or intermetallic compounds. 5) complex hydrides of light elements such as alanates and boranates, 6) storage via chemical reactions. Recently, the storage as hydrogen hydrates at 50 bar using promoters has been reported by F. Peetom. The paper discusses the feasibility of each of these storing alternatives. The authors presents their experience and results of the work in the field of metal hydrides and application obtained since 1975. All classes of hydrogen absorbing intermetallic compounds were studied: LaNi 5 , FeTi, Ti

  20. Alloying effect on the electronic structures of hydrogen storage compounds

    Energy Technology Data Exchange (ETDEWEB)

    Yukawa, H.; Moringa, M.; Takahashi, Y. [Nagoya Univ. (Japan). Dept. of Mater. Sci. and Eng.

    1997-05-20

    The electronic structures of hydrogenated LaNi{sub 5} containing various 3d transition elements were investigated by the DV-X{alpha} molecular orbital method. The hydrogen atom was found to form a strong chemical bond with the Ni rather than the La atoms. The alloying modified the chemical bond strengths between atoms in a small metal octahedron containing a hydrogen atom at the center, resulting in the change in the hydrogen absorption and desorption characteristics of LaNi{sub 5} with alloying. (orig.) 7 refs.

  1. Leaching of metals from large pieces of printed circuit boards using citric acid and hydrogen peroxide.

    Science.gov (United States)

    Jadhav, Umesh; Su, C; Hocheng, Hong

    2016-12-01

    In the present study, the leaching of metals from large pieces of computer printed circuit boards (CPCBs) was studied. A combination of citric acid (0.5 M) and 1.76 M hydrogen peroxide (H 2 O 2 ) was used to leach the metals from CPCB piece. The influence of system variables such as H 2 O 2 concentration, concentration of citric acid, shaking speed, and temperature on the metal leaching process was investigated. The complete metal leaching was achieved in 4 h from a 4 × 4 cm CPCB piece. The presence of citric acid and H 2 O 2 together in the leaching solution is essential for complete metal leaching. The optimum addition amount of H 2 O 2 was 5.83 %. The citric acid concentration and shaking speed had an insignificant effect on the leaching of metals. The increase in the temperature above 30 °C showed a drastic effect on metal leaching process.

  2. Comparison of reactivity on step and terrace sites of Pd (3 3 2) surface for the dissociative adsorption of hydrogen: A quantum chemical molecular dynamics study

    International Nuclear Information System (INIS)

    Ahmed, Farouq; Nagumo, Ryo; Miura, Ryuji; Ai, Suzuki; Tsuboi, Hideyuki; Hatakeyama, Nozomu; Endou, Akira; Takaba, Hiromitsu; Kubo, Momoji; Miyamoto, Akira

    2011-01-01

    The notion of 'active sites' is fundamental to heterogeneous catalysis. However, the exact nature of the active sites, and hence the mechanism by which they act, are still largely a matter of speculation. In this study, we have presented a systematic quantum chemical molecular dynamics (QCMD) calculations for the interaction of hydrogen on different step and terrace sites of the Pd (3 3 2) surface. Finally the dissociative adsorption of hydrogen on step and terrace as well as the influence of surface hydrogen vacancy for the dissociative adsorption of hydrogen has been investigated through QCMD. This is a state-of-the-art method for calculating the interaction of atoms and molecules with metal surfaces. It is found that fully hydrogen covered (saturated) step sites can dissociate hydrogen moderately and that a monovacancy surface is suitable for significant dissociative adsorption of hydrogen. However in terrace site of the surface we have found that dissociation of hydrogen takes place only on Pd sites where the metal atom is not bound to any pre-adsorbed hydrogen atoms. Furthermore, from the molecular dynamics and electronic structure calculations, we identify a number of consequences for the interpretation and modeling of diffusion experiments demonstrating the coverage and directional dependence of atomic hydrogen diffusion on stepped palladium surface.

  3. A hydrogen production experiment by the thermo-chemical and electrolytic hybrid hydrogen production in lower temperature range. System viability and preliminary thermal efficiency estimation

    International Nuclear Information System (INIS)

    Takai, Toshihide; Nakagiri, Toshio; Inagaki, Yoshiyuki

    2008-10-01

    A new experimental apparatus by the thermo-chemical and electrolytic Hybrid-Hydrogen production in Lower Temperature range (HHLT) was developed and hydrogen production experiment was performed to confirm the system operability. Hydrogen production efficiency was estimated and technical problems were clarified through the experimental results. Stable operation of the SO 3 electrolysis cell and the sulfur dioxide solution electrolysis cell were confirmed during experimental operation and any damage which would be affected solid operation was not detected under post operation inspection. To improve hydrogen production efficiency, it was found that the reduction of sulfuric acid circulation and the decrease in the cell voltage were key issues. (author)

  4. A survey of processes for producing hydrogen fuel from different sources for automotive-propulsion fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Brown, L.F.

    1996-03-01

    Seven common fuels are compared for their utility as hydrogen sources for proton-exchange-membrane fuel cells used in automotive propulsion. Methanol, natural gas, gasoline, diesel fuel, aviation jet fuel, ethanol, and hydrogen are the fuels considered. Except for the steam reforming of methanol and using pure hydrogen, all processes for generating hydrogen from these fuels require temperatures over 1000 K at some point. With the same two exceptions, all processes require water-gas shift reactors of significant size. All processes require low-sulfur or zero-sulfur fuels, and this may add cost to some of them. Fuels produced by steam reforming contain {approximately}70-80% hydrogen, those by partial oxidation {approximately}35-45%. The lower percentages may adversely affect cell performance. Theoretical input energies do not differ markedly among the various processes for generating hydrogen from organic-chemical fuels. Pure hydrogen has severe distribution and storage problems. As a result, the steam reforming of methanol is the leading candidate process for on-board generation of hydrogen for automotive propulsion. If methanol unavailability or a high price demands an alternative process, steam reforming appears preferable to partial oxidation for this purpose.

  5. THE HYDROGEN-FUELLED INTERNAL COMBUSTION ENGINES FOR MARINE APPLICATIONS WITH A CASE STUDY

    Directory of Open Access Journals (Sweden)

    Ibrahim S. Seddiek

    2015-03-01

    Full Text Available Modern marine power plants have been designed to improve the overall ship’s efficiency. This pushed the designers of marine machinery to search for unconventional fuels for these plants. During the previous years, diesel oil has been extensively used on-board ships. Due to the high price of light diesel oil and the environmental problems resulting from the use of heavy fuel oil, it has become necessary to search for an alternative to traditional fuels. As a result, natural gas fuel has been used on-board some types of ships, especially short-voyage cruise ships. Unfortunately, there are still some technical and logistic problems related to the use of natural gas as a fuel, especially as it is considered a non-renewable energy source. The use of hydrogen fuel on-board ships, particularly in modern power plants may contribute to overcoming the above problems. The present paper considers the possibility of the use of hydrogen fuel for marine applications and discusses different stages of hydrogen gas cycle beginning with hydrogen generation process from clean energy until using it as fuel for internal combustion engines on-board one RO/RO ship, named Taba, operating in the Mediterranean Sea. Compared to the diesel engine, the hydrogen fuelled engine is found to be lower in thermal efficiency and fuel consumption, however, some adjustments are needed.

  6. Empirical Correction for Differences in Chemical Exchange Rates in Hydrogen Exchange-Mass Spectrometry Measurements.

    Science.gov (United States)

    Toth, Ronald T; Mills, Brittney J; Joshi, Sangeeta B; Esfandiary, Reza; Bishop, Steven M; Middaugh, C Russell; Volkin, David B; Weis, David D

    2017-09-05

    A barrier to the use of hydrogen exchange-mass spectrometry (HX-MS) in many contexts, especially analytical characterization of various protein therapeutic candidates, is that differences in temperature, pH, ionic strength, buffering agent, or other additives can alter chemical exchange rates, making HX data gathered under differing solution conditions difficult to compare. Here, we present data demonstrating that HX chemical exchange rates can be substantially altered not only by the well-established variables of temperature and pH but also by additives including arginine, guanidine, methionine, and thiocyanate. To compensate for these additive effects, we have developed an empirical method to correct the hydrogen-exchange data for these differences. First, differences in chemical exchange rates are measured by use of an unstructured reporter peptide, YPI. An empirical chemical exchange correction factor, determined by use of the HX data from the reporter peptide, is then applied to the HX measurements obtained from a protein of interest under different solution conditions. We demonstrate that the correction is experimentally sound through simulation and in a proof-of-concept experiment using unstructured peptides under slow-exchange conditions (pD 4.5 at ambient temperature). To illustrate its utility, we applied the correction to HX-MS excipient screening data collected for a pharmaceutically relevant IgG4 mAb being characterized to determine the effects of different formulations on backbone dynamics.

  7. 78 FR 14299 - Notification of a Public Meeting of the Science Advisory Board Chemical Assessment Advisory...

    Science.gov (United States)

    2013-03-05

    ... ENVIRONMENTAL PROTECTION AGENCY [FRL-9786-6] Notification of a Public Meeting of the Science...: Notice. SUMMARY: The Environmental Protection Agency (EPA or agency) Science Advisory Board (SAB) Staff Office announces a public meeting of the SAB Chemical Assessment Advisory Committee (CAAC) to receive a...

  8. INVESTIGATIONS ON BIOCHEMICAL PURIFICATION OF GROUND WATER FROM HYDROGEN SULFIDE

    Directory of Open Access Journals (Sweden)

    Yu. P. Sedlukho

    2015-01-01

    Full Text Available The paper considers problems and features of biochemical removal of hydrogen sulfide from ground water. The analysis of existing methods for purification of ground water from hydrogen sulfide has been given in the paper. The paper has established shortcomings of physical and chemical purification of ground water. While using aeration methods for removal of hydrogen sulfide formation of colloidal sulfur that gives muddiness and opalescence to water occurs due to partial chemical air oxidation. In addition to this violation of sulfide-carbonate equilibrium taking place in the process of aeration due to desorption of H2S and CO2, often leads to clogging of degasifier nozzles with formed CaCO3 that causes serious operational problems. Chemical methods require relatively large flow of complex reagent facilities, storage facilities and transportation costs.In terms of hydrogen sulfide ground water purification the greatest interest is given to the biochemical method. Factors deterring widespread application of the biochemical method is its insufficient previous investigation and necessity to execute special research in order to determine optimal process parameters while purifying groundwater of a particular water supply source. Biochemical methods for oxidation of sulfur compounds are based on natural biological processes that ensure natural sulfur cycle. S. Vinogradsky has established a two-stage mechanism for oxidation of hydrogen sulfide with sulfur bacteria (Beggiatoa. The first stage presupposes oxidation of hydrogen sulphide to elemental sulfur which is accumulating in the cytoplasm in the form of globules. During the second stage sulfur bacteria begin to oxidize intracellular sulfur to sulfuric acid due to shortage of hydrogen sulfide.The paper provides the results of technological tests of large-scale pilot plants for biochemical purification of groundwater from hydrogen sulfide in semi-industrial conditions. Dependences of water quality

  9. A DFT study of hydrogen adsorption on Be, Mg and Ca frameworks in erionite zeolite

    Energy Technology Data Exchange (ETDEWEB)

    Fellah, Mehmet Ferdi, E-mail: mferdi.fellah@btu.edu.tr

    2017-02-01

    Highlights: • Mg-ERI and Ca-ERI clusters have much lower chemical potential and hardness. • Adsorption enthalpies for Mg- and Ca-ERI are importantly greater than the liquefaction enthalpy of hydrogen. • Mg-ERI and Ca-ERI clusters have much HOMO-LUMO gap indicating higher reactivity. • Ca- and Mg-ERI are potential cryoadsorbent materials for hydrogen storage. - Abstract: The molecular hydrogen adsorption was investigated on additional frameworks with earth alkaline metal atoms (Be, Mg and Ca) in 24T ERI zeolite cluster model by means of Density Functional Theory study. HOMO and LUMO energy values, chemical potential, chemical hardness, electronegativity, adsorption energy and adsorption enthalpy values have been calculated in this study. Mg-ERI and Ca-ERI clusters have much lower chemical potentials with much lower adsorption energy values when compared to the value of Be-ERI cluster. Additionally, they are softer than Be-ERI cluster with respect to their lower chemical hardness values. Hydrogen adsorption enthalpy values were computed as −3.6 and −3.9 kJ/mol on Mg-ERI and Ca-ERI clusters, respectively. These adsorption enthalpy values are significantly larger than the enthalpy value of liquefaction for hydrogen molecule. This consequently specifies that Mg-ERI and Ca-ERI zeolite structures which have higher chemical reactivity appear to be a promising candidate cryoadsorbent for hydrogen storage.

  10. Hydrogen enrichment of an internal combustion engine via closed loop thermochemical recuperation

    NARCIS (Netherlands)

    Zwitserlood, J.G.; Hofman, T.; Erickson, P.A.

    2013-01-01

    Hydrogen enrichment in an internal combustion engine can greatly improve efficiency and at the same time reduce emissions without the need for extensive engine modifications. One option for a hydrogen source for the enrichment is actively producing hydrogen on-board the vehicle through steam

  11. Expert Opinion Analysis on Renewable Hydrogen Storage Systems Potential in Europe

    Directory of Open Access Journals (Sweden)

    Davide Astiaso Garcia

    2016-11-01

    Full Text Available Among the several typologies of storage technologies, mainly on different physical principles (mechanical, electrical and chemical, hydrogen produced by power to gas (P2G from renewable energy sources complies with chemical storage principle and is based on the conversion of electrical energy into chemical energy by means of the electrolysis of water which does not produce any toxic or climate-relevant emission. This paper aims to pinpoint the potential uses of renewable hydrogen storage systems in Europe, analysing current and potential locations, regulatory framework, governments’ outlooks, economic issues, and available renewable energy amounts. The expert opinion survey, already used in many research articles on different topics including energy, has been selected as an effective method to produce realistic results. The obtained results highlight strategies and actions to optimize the storage of hydrogen produced by renewables to face varying electricity demand and generation-driven fluctuations reducing the negative effects of the increasing share of renewables in the energy mix of European Countries.

  12. Some aspects on the role of hydrogen in the cold crack develoment process on welding

    International Nuclear Information System (INIS)

    Bourges, P.; Faure, F.

    1983-03-01

    Examination of the hydrogen input during welding (humidity of the electrode coatings, humidity of the wires, ribbon, and weld fluxing) and the means to minimize these hydrogen inputs. Description of various examples of cold crack development in welded joints caused by hydrogen, influence of the chemical composition, of the thermal processing on the two metals joints, influence of sulfur on cold crack on low alloy steels [fr

  13. Influence of hydrogen on chemical vapour synthesis of different ...

    Indian Academy of Sciences (India)

    Administrator

    The role of hydrogen on the surface passivation behaviour of the Ni catalyst and its ..... Chae S J, Güneş F, Kim K K, Kim E S, Han G H, Kim S M,. Shin H-J, Yoon ... Xiong Y G, Suda Y, Wang D Z, Huang Y J and Ren Z F 2005. Nanotechnology ...

  14. Sensitive Capacitive-type Hydrogen Sensor Based on Ni Thin Film in Different Hydrogen Concentrations.

    Science.gov (United States)

    Pour, Ghobad Behzadi; Aval, Leila Fekri; Eslami, Shahnaz

    2018-04-01

    Hydrogen sensors are micro/nano-structure that are used to locate hydrogen leaks. They are considered to have fast response/recovery time and long lifetime as compared to conventional gas sensors. In this paper, fabrication of sensitive capacitive-type hydrogen gas sensor based on Ni thin film has been investigated. The C-V curves of the sensor in different hydrogen concentrations have been reported. Dry oxidation was done in thermal chemical vapor deposition furnace (TCVD). For oxidation time of 5 min, the oxide thickness was 15 nm and for oxidation time 10 min, it was 20 nm. The Ni thin film as a catalytic metal was deposited on the oxide film using electron gun deposition. Two MOS sensors were compared with different oxide film thickness and different hydrogen concentrations. The highest response of the two MOS sensors with 15 nm and 20 nm oxide film thickness in 4% hydrogen concentration was 87.5% and 65.4% respectively. The fast response times for MOS sensors with 15 nm and 20 nm oxide film thickness in 4% hydrogen concentration was 8 s and 21 s, respectively. By increasing the hydrogen concentration from 1% to 4%, the response time for MOS sensor (20nm oxide thickness), was decreased from 28s to 21s. The recovery time was inversely increased from 237s to 360s. The experimental results showed that the MOS sensor based on Ni thin film had a quick response and a high sensitivity.

  15. A lumped-parameter model for cryo-adsorber hydrogen storage tank

    Energy Technology Data Exchange (ETDEWEB)

    Senthil Kumar, V.; Raghunathan, K. [India Science Lab, General Motors R and D, Creator Building, International Technology Park, Bangalore 560066 (India); Kumar, Sudarshan [Chemical and Environmental Sciences Lab, General Motors R and D, 30500 Mound Road, Warren, MI 48090 (United States)

    2009-07-15

    One of the primary requirements for commercialization of hydrogen fuel-cell vehicles is the on-board storage of hydrogen in sufficient quantities. On-board storage of hydrogen by adsorption on nano-porous adsorbents at around liquid nitrogen temperatures and moderate pressures is considered viable and competitive with other storage technologies: liquid hydrogen, compressed gas, and metallic or complex hydrides. The four cryo-adsorber fuel tank processes occur over different time scales: refueling over a few minutes, discharge over a few hours, dormancy over a few days, and venting over a few weeks. The slower processes i.e. discharge, dormancy and venting are expected to have negligible temperature gradients within the bed, and hence are amenable to a lumped-parameter analysis. Here we report a quasi-static lumped-parameter model for the cryo-adsorber fuel tank, and discuss the results for these slower processes. We also describe an alternative solution method for dormancy and venting based on the thermodynamic state description. (author)

  16. 76 FR 76122 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2011-12-06

    ... CHEMICAL SAFETY AND HAZARD INVESTIGATION BOARD Senior Executive Service Performance Review Board... change in the membership of the Senior Executive Service Performance Review Board for the Chemical Safety... Senior Executive Service (SES) and makes recommendations as to final annual performance ratings for...

  17. 78 FR 57837 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2013-09-20

    ... CHEMICAL SAFETY AND HAZARD INVESTIGATION BOARD Senior Executive Service Performance Review Board... change in the membership of the Senior Executive Service Performance Review Board for the Chemical Safety... Senior Executive Service (SES) and makes recommendations as to final annual performance ratings for...

  18. Hail hydrogen

    International Nuclear Information System (INIS)

    Hairston, D.

    1996-01-01

    After years of being scorned and maligned, hydrogen is finding favor in environmental and process applications. There is enormous demand for the industrial gas from petroleum refiners, who need in creasing amounts of hydrogen to remove sulfur and other contaminants from crude oil. In pulp and paper mills, hydrogen is turning up as hydrogen peroxide, displacing bleaching agents based on chlorine. Now, new technologies for making hydrogen have the industry abuzz. With better capabilities of being generated onsite at higher purity levels, recycled and reused, hydrogen is being prepped for a range of applications, from waste reduction to purification of Nylon 6 and hydrogenation of specialty chemicals. The paper discusses the strong market demand for hydrogen, easier routes being developed for hydrogen production, and the use of hydrogen in the future

  19. Achievement report on research and development in the Sunshine Project in fiscal 1976. Comprehensive discussion on hydrogen utilizing subsystems and research on peripheral technologies (Research for chemical utilization); 1976 nendo suiso riyo subsystem no sogoteki kento to shuhen gijutsu ni kansuru kenkyu seika hokokusho. Kagaku riyo ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1977-04-15

    Surveys and studies were performed on chemical utilization of hydrogen regarding its status of development and utilization inside and outside the country, as well as its future prospect. This paper describes chemical utilization of hydrogen in ammonia, methanol, petroleum refining and other industries as the existing fields. It also describes chemical utilization of oxygen in iron and steel, chemical and other industries. It describes methanol as a pollution-free auxiliary fuel for electric power plants as a new type of hydrogen application. Acetic acid made by using the Monsanto method which carbonylate methanol is drawing attention in terms of economy, and is in the phase of discussing commercialization. Synthesizing ethylene glycol from carbon monoxide and hydrogen may be conceived economically. Methanol for synthesized protein depends on the possibility of future development. In the iron and steel industry, electric furnace steel makers are planning production of reduced iron, where the direct reduction process using hydrogen is considered as a complementary process, including countermeasures for scrap iron. This paper estimates hydrogen amount as a raw material for ammonia to remove NOx by using the ammonia reduction process. It also describes possibility of other types of utilization. (NEDO)

  20. Accident investigation board report on the May 14, 1997, chemical explosion at the Plutonium Reclamation Facility, Hanford Site,Richland, Washington - summary report

    International Nuclear Information System (INIS)

    Gerton, R.E.

    1997-01-01

    This report is a summary of the Accident Investigation Board Report on the May 14, 1997, Chemical Explosion at the Plutonium Reclamation Facility, Hanford Site, Richland, Washington (DOE/RL-97-59). The referenced report provides a greater level of detail and includes a complete discussion of the facts identified, analysis of those facts, conclusions derived from the analysis, identification of the accident's causal factors, and recommendations that should be addressed through follow-up action by the U.S. Department of Energy and its contractors. This companion document provides a concise summary of that report, with emphasis on management issues. Evaluation of emergency and occupational health response to, and radiological and chemical releases from, this accident was not within the scope of this investigation, but is the subject of a separate investigation and report (see DOE/RL-97-62)

  1. 75 FR 1028 - Senior Executive Service Performance Review Board

    Science.gov (United States)

    2010-01-08

    ... CHEMICAL SAFETY AND HAZARD INVESTIGATION BOARD Senior Executive Service Performance Review Board... change in the membership of the Senior Executive Service Performance Review Board for the Chemical Safety... performance ratings of members of the Senior Executive Service (SES) and makes recommendations as to final...

  2. Formation of hydrogen-related traps in electron-irradiated n-type silicon by wet chemical etching

    International Nuclear Information System (INIS)

    Tokuda, Yutaka; Shimada, Hitoshi

    1998-01-01

    Interaction of hydrogen atoms and vacancy-related defects in 10 MeV electron-irradiated n-type silicon has been studied by deep-level transient spectroscopy. Hydrogen has been incorporated into electron-irradiated n-type silicon by wet chemical etching. The reduction of the concentration of the vacancy-oxygen pair and divacancy occurs by the incorporation of hydrogen, while the formation of the NH1 electron trap (E c - 0.31 eV) is observed. Further decrease of the concentration of the vacancy-oxygen pair and further increase of the concentration of the NH1 trap are observed upon subsequent below-band-gap light illumination. It is suggested that the trap NH1 is tentatively ascribed to the vacancy-oxygen pair which is partly saturated with hydrogen

  3. Runaway chemical reaction exposes community to highly toxic chemicals

    International Nuclear Information System (INIS)

    Kaszniak, Mark; Vorderbrueggen, John

    2008-01-01

    The U.S. Chemical Safety and Hazard Investigation Board (CSB) conducted a comprehensive investigation of a runaway chemical reaction at MFG Chemical (MFG) in Dalton, Georgia on April 12, 2004 that resulted in the uncontrolled release of a large quantity of highly toxic and flammable allyl alcohol and allyl chloride into the community. Five people were hospitalized and 154 people required decontamination and treatment for exposure to the chemicals. This included police officers attempting to evacuate the community and ambulance personnel who responded to 911 calls from residents exposed to the chemicals. This paper presents the findings of the CSB report (U.S. Chemical Safety and Hazard Investigation Board (CSB), Investigation Report: Toxic Chemical Vapor Cloud Release, Report No. 2004-09-I-GA, Washington DC, April 2006) including a discussion on tolling practices; scale-up of batch reaction processes; Process Safety Management (PSM) and Risk Management Plan (RMP) implementation; emergency planning by the company, county and the city; and emergency response and mitigation actions taken during the incident. The reactive chemical testing and atmospheric dispersion modeling conducted by CSB after the incident and recommendations adopted by the Board are also discussed

  4. ERDA's Chemical Energy Storage Program

    Science.gov (United States)

    Swisher, J. H.; Kelley, J. H.

    1977-01-01

    The Chemical Energy Storage Program is described with emphasis on hydrogen storage. Storage techniques considered include pressurized hydrogen gas storage, cryogenic liquid hydrogen storage, storage in hydride compounds, and aromatic-alicyclic hydrogen storage. Some uses of energy storage are suggested. Information on hydrogen production and hydrogen use is also presented. Applications of hydrogen energy systems include storage of hydrogen for utilities load leveling, industrial marketing of hydrogen both as a chemical and as a fuel, natural gas supplementation, vehicular applications, and direct substitution for natural gas.

  5. Purification of hydrogen under a free or combined form in a gaseous mixture, by chemical reactions with uranium

    International Nuclear Information System (INIS)

    Caron Charles, M.

    1988-03-01

    Within the framework of the european fusion program, we are dealing with the purification of hydrogen (tritium) under a free or combined form, from a H 2 , N 2 , NH 3 , CH 4 , O 2 , gaseous mixture. The process consists in cracking the hydrogenated molecules and absorbing the impurities by chemical reactions with uranium, without holding back hydrogen. In the temperature range: 950 K [fr

  6. Recent advances on membranes and membrane reactors for hydrogen production

    NARCIS (Netherlands)

    Gallucci, F.; Fernandez Gesalaga, E.; Corengia, P.; Sint Annaland, van M.

    2013-01-01

    Membranes and membrane reactors for pure hydrogen production are widely investigated not only because of the important application areas of hydrogen, but especially because mechanically and chemically stable membranes with high perm-selectivity towards hydrogen are available and are continuously

  7. Influence of krypton atoms on the structure of hydrogenated amorphous carbon deposited by plasma enhanced chemical vapor deposition

    Science.gov (United States)

    Oliveira, M. H.; Viana, G. A.; de Lima, M. M.; Cros, A.; Cantarero, A.; Marques, F. C.

    2010-12-01

    Hydrogenated amorphous carbon (a-C:H) films were prepared by plasma enhanced chemical vapor deposition using methane (CH4) plus krypton (Kr) mixed atmosphere. The depositions were performed as function of the bias voltage and krypton partial pressure. The goal of this work was to study the influence of krypton gas on the physical properties of a-C:H films deposited on the cathode electrode. Krypton concentration up to 1.6 at. %, determined by Rutherford Back-Scattering, was obtained at high Kr partial pressure and bias of -120 V. The structure of the films was analyzed by means of optical transmission spectroscopy, multi-wavelength Raman scattering and Fourier Transform Infrared spectroscopy. It was verified that the structure of the films remains unchanged up to a concentration of Kr of about 1.0 at. %. A slight graphitization of the films occurs for higher concentration. The observed variation in the film structure, optical band gap, stress, and hydrogen concentration were associated mainly with the subplantation process of hydrocarbons radicals, rather than the krypton ion energy.

  8. Influence of krypton atoms on the structure of hydrogenated amorphous carbon deposited by plasma enhanced chemical vapor deposition

    International Nuclear Information System (INIS)

    Oliveira, M. H. Jr.; Viana, G. A.; Marques, F. C.; Lima, M. M. Jr. de; Cros, A.; Cantarero, A.

    2010-01-01

    Hydrogenated amorphous carbon (a-C:H) films were prepared by plasma enhanced chemical vapor deposition using methane (CH 4 ) plus krypton (Kr) mixed atmosphere. The depositions were performed as function of the bias voltage and krypton partial pressure. The goal of this work was to study the influence of krypton gas on the physical properties of a-C:H films deposited on the cathode electrode. Krypton concentration up to 1.6 at. %, determined by Rutherford Back-Scattering, was obtained at high Kr partial pressure and bias of -120 V. The structure of the films was analyzed by means of optical transmission spectroscopy, multi-wavelength Raman scattering and Fourier Transform Infrared spectroscopy. It was verified that the structure of the films remains unchanged up to a concentration of Kr of about 1.0 at. %. A slight graphitization of the films occurs for higher concentration. The observed variation in the film structure, optical band gap, stress, and hydrogen concentration were associated mainly with the subplantation process of hydrocarbons radicals, rather than the krypton ion energy.

  9. LANL Virtual Center for Chemical Hydrogen Storage: Chemical Hydrogen Storage Using Ultra-high Surface Area Main Group Materials

    Energy Technology Data Exchange (ETDEWEB)

    Susan M. Kauzlarich; Phillip P. Power; Doinita Neiner; Alex Pickering; Eric Rivard; Bobby Ellis, T. M.; Atkins, A. Merrill; R. Wolf; Julia Wang

    2010-09-05

    The focus of the project was to design and synthesize light element compounds and nanomaterials that will reversibly store molecular hydrogen for hydrogen storage materials. The primary targets investigated during the last year were amine and hydrogen terminated silicon (Si) nanoparticles, Si alloyed with lighter elements (carbon (C) and boron (B)) and boron nanoparticles. The large surface area of nanoparticles should facilitate a favorable weight to volume ratio, while the low molecular weight elements such as B, nitrogen (N), and Si exist in a variety of inexpensive and readily available precursors. Furthermore, small NPs of Si are nontoxic and non-corrosive. Insights gained from these studies will be applied toward the design and synthesis of hydrogen storage materials that meet the DOE 2010 hydrogen storage targets: cost, hydrogen capacity and reversibility. Two primary routes were explored for the production of nanoparticles smaller than 10 nm in diameter. The first was the reduction of the elemental halides to achieve nanomaterials with chloride surface termination that could subsequently be replaced with amine or hydrogen. The second was the reaction of alkali metal Si or Si alloys with ammonium halides to produce hydrogen capped nanomaterials. These materials were characterized via X-ray powder diffraction, TEM, FTIR, TG/DSC, and NMR spectroscopy.

  10. Economic Analysis for Nuclear Hydrogen Production System Based on HyS Process

    International Nuclear Information System (INIS)

    Yang, Kyeong Jin; Lee, Ki Young; Lee, Tae Hoon; Chang, Jong Hwa

    2009-01-01

    The current promising base for massive hydrogen production on high temperature environment derives primarily from three sources: the commercial production of chemicals for the sulfur-iodine (SI) process, the development of solid-oxide fuel cells (SOFC), and the hybrid method of chemicals and fuel cells. The three kinds of process requires high temperature heat energy over 850∼950 .deg. C for the efficient and economic hydrogen production. One of the clean, economic, and moreover promising heat sources supplied to the process is nuclear plants. The nuclear plants producing high temperature heat energy over 950 .deg. C are well known as Very High Temperature Reactors (VHTR) which could have two types of prismatic and pebble-bed cores along reactor core shape. In this paper, we report on the Hybrid Sulfur Process (HyS), and the estimated costs for the system which composes of VHTR of prismatic core type and HyS plant. Nuclear hydrogen production system based on HyS process has been configured to optimally use the thermal energy from VHTR and electric energy to produce hydrogen and oxygen from clean water. High temperature thermal energy is transferred to the HyS process by way of intermediate heat exchanger (IHX) with associated piping. In this paper, the hydrogen production costs for a system composed of a VHTR with six 600MWth module, a power conversion unit (PCU) and a HyS plant are presented, where the thermal energy produced in two module was converted to electric energy in PCU and then transferred to the electrolysis cells for hydrogen production and circulating units on HyS plant, and the remaining thermal energy was supplied to chemical process on HyS plants. As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GT-MHR are estimated in the necessary input data on a Korean specific basis. G4- ECONS was appropriately modified to calculate the cost for hydrogen production

  11. Chemical corrosion by chlorides on ancient-like bronzes and treatment by hydrogen glow discharge plasma

    Science.gov (United States)

    Papadopoulou, O.; Novakovic, J.; Vassiliou, P.; Filippaki, E.; Bassiakos, Y.

    2013-12-01

    Three representative ancient-like bronzes are employed for the chemical synthesis of Cu2(OH)3Cl rich patinas in order to study the influence of the alloying elements in the evolution of the chloride attack and to further conduct stabilization treatment via Hydrogen Glow Discharge Plasma (HGDP) at low temperature and pressure. The corrosion behavior of specimens having Sn and Pb as main alloying elements is governed by a decuprification mechanism and by the formation of Sn-Pb-O enriched barrier layers. In the case of the Zn containing alloy, dezincification is more pronounced at the corrosion initial stages, and copper species predominate the corrosion products evolution. A three-hour HGDP treatment leads to Cu+ production and metallic Cu, Sn, Zn, and Pb redeposition, as a result of metal cation reduction. This process is accompanied by partial removal of Cl species, O diminution, and change in coloration. The further increase of the Cl/O atomic ratio measured on the post-treated surfaces leads to the formation of nantokite and thus to the conclusion that the stabilization of objects with extensive Cl attack is not feasible by HGDP without preliminary chemical treatment.

  12. Extent of hydrogen coverage of Si(001) under chemical vapor deposition conditions from ab initio approaches

    International Nuclear Information System (INIS)

    Rosenow, Phil; Tonner, Ralf

    2016-01-01

    The extent of hydrogen coverage of the Si(001) c(4 × 2) surface in the presence of hydrogen gas has been studied with dispersion corrected density functional theory. Electronic energy contributions are well described using a hybrid functional. The temperature dependence of the coverage in thermodynamic equilibrium was studied computing the phonon spectrum in a supercell approach. As an approximation to these demanding computations, an interpolated phonon approach was found to give comparable accuracy. The simpler ab initio thermodynamic approach is not accurate enough for the system studied, even if corrections by the Einstein model for surface vibrations are considered. The on-set of H 2 desorption from the fully hydrogenated surface is predicted to occur at temperatures around 750 K. Strong changes in hydrogen coverage are found between 1000 and 1200 K in good agreement with previous reflectance anisotropy spectroscopy experiments. These findings allow a rational choice for the surface state in the computational treatment of chemical reactions under typical metal organic vapor phase epitaxy conditions on Si(001).

  13. Extent of hydrogen coverage of Si(001) under chemical vapor deposition conditions from ab initio approaches

    Energy Technology Data Exchange (ETDEWEB)

    Rosenow, Phil; Tonner, Ralf, E-mail: tonner@chemie.uni-marburg.de [Fachbereich Chemie and Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Hans-Meerwein-Straße, Marburg 35032 (Germany)

    2016-05-28

    The extent of hydrogen coverage of the Si(001) c(4 × 2) surface in the presence of hydrogen gas has been studied with dispersion corrected density functional theory. Electronic energy contributions are well described using a hybrid functional. The temperature dependence of the coverage in thermodynamic equilibrium was studied computing the phonon spectrum in a supercell approach. As an approximation to these demanding computations, an interpolated phonon approach was found to give comparable accuracy. The simpler ab initio thermodynamic approach is not accurate enough for the system studied, even if corrections by the Einstein model for surface vibrations are considered. The on-set of H{sub 2} desorption from the fully hydrogenated surface is predicted to occur at temperatures around 750 K. Strong changes in hydrogen coverage are found between 1000 and 1200 K in good agreement with previous reflectance anisotropy spectroscopy experiments. These findings allow a rational choice for the surface state in the computational treatment of chemical reactions under typical metal organic vapor phase epitaxy conditions on Si(001).

  14. Extent of hydrogen coverage of Si(001) under chemical vapor deposition conditions from ab initio approaches

    Science.gov (United States)

    Rosenow, Phil; Tonner, Ralf

    2016-05-01

    The extent of hydrogen coverage of the Si(001) c(4 × 2) surface in the presence of hydrogen gas has been studied with dispersion corrected density functional theory. Electronic energy contributions are well described using a hybrid functional. The temperature dependence of the coverage in thermodynamic equilibrium was studied computing the phonon spectrum in a supercell approach. As an approximation to these demanding computations, an interpolated phonon approach was found to give comparable accuracy. The simpler ab initio thermodynamic approach is not accurate enough for the system studied, even if corrections by the Einstein model for surface vibrations are considered. The on-set of H2 desorption from the fully hydrogenated surface is predicted to occur at temperatures around 750 K. Strong changes in hydrogen coverage are found between 1000 and 1200 K in good agreement with previous reflectance anisotropy spectroscopy experiments. These findings allow a rational choice for the surface state in the computational treatment of chemical reactions under typical metal organic vapor phase epitaxy conditions on Si(001).

  15. Gas-phase ion/molecule isotope-exchange reactions: methodology for counting hydrogen atoms in specific organic structural environments by chemical ionization mass spectrometry

    International Nuclear Information System (INIS)

    Hunt, D.F.; Sethi, S.K.

    1980-01-01

    Ion/molecule reactions are described which facilitate exchange of hydrogens for deuteriums in a variety of different chemical environments. Aromatic hydrogens in alkylbenzenes, oxygenated benzenes, m-toluidine, m-phenylenediamine, thiophene, and several polycyclic aromatic hydrocarbons and metallocenes are exchanged under positive ion CI conditions by using either D 2 O, EtOD, or ND 3 as the reagent gas. Aromatic hydrogens, benzylic hydrogens, and hydrogens on carbon adjacent to carbonyl groups suffer exchange under negative ion CI conditions in ND 3 , D 2 O, and EtOD, respectively. A possible mechanism for the exchange process is discussed. 1 figure, 2 tables

  16. An effect-directed strategy for characterizing emerging chemicals in food contact materials made from paper and board

    DEFF Research Database (Denmark)

    Rosenmai, Anna Kjerstine; Bengtström, Linda; Taxvig, Camilla

    2017-01-01

    Food contact materials (FCM) are any type of item intended to come into contact with foods and thus represent a potential source for human exposure to chemicals. Regarding FCMs made of paper and board, information pertaining to their chemical constituents and the potential impacts on human health...... FCMs exhibited activities in at least one assay. As proof-of-principle, FCM samples obtained from a sandwich wrapper and a pizza box were carried through a complete step-by-step multi-tiered approach. The pizza box exhibited ER activity, likely caused by the presence of bisphenol A, dibutyl phthalate......, and benzylbutyl phthalate. The sandwich wrapper exhibited AR antagonism, likely caused by abietic acid and dehydroabietic acid. Migration studies confirmed that the active chemicals can transfer from FCMs to food simulants. In conclusion, we report an effect-directed strategy that can identify hazards posed...

  17. Biological conversion of carbon dioxide and hydrogen into liquid fuels and industrial chemicals.

    Science.gov (United States)

    Hawkins, Aaron S; McTernan, Patrick M; Lian, Hong; Kelly, Robert M; Adams, Michael W W

    2013-06-01

    Non-photosynthetic routes for biological fixation of carbon dioxide into valuable industrial chemical precursors and fuels are moving from concept to reality. The development of 'electrofuel'-producing microorganisms leverages techniques in synthetic biology, genetic and metabolic engineering, as well as systems-level multi-omic analysis, directed evolution, and in silico modeling. Electrofuel processes are being developed for a range of microorganisms and energy sources (e.g. hydrogen, formate, electricity) to produce a variety of target molecules (e.g. alcohols, terpenes, alkenes). This review examines the current landscape of electrofuel projects with a focus on hydrogen-utilizing organisms covering the biochemistry of hydrogenases and carbonic anhydrases, kinetic and energetic analyses of the known carbon fixation pathways, and the state of genetic systems for current and prospective electrofuel-producing microorganisms. Copyright © 2013 Elsevier Ltd. All rights reserved.

  18. In situ measurements of hydrogen concentration and flux between 160 and 300 km in the thermosphere

    International Nuclear Information System (INIS)

    Breig, E.L.; Hanson, W.B.; Hoffman, J.H.; Kayser, D.C.

    1976-01-01

    Thermospheric concentrations of neutral atomic hydrogen near and below the F peak are directly related to H + , O + and atomic oxygen concentrations through the charge exchange equilibrium that is established between hydrogen and oxygen at these altitudes. This chemical relationship, together with in situ measurements of ionospheric and neutral atmospheric concentrations by instrumentation on board the Atmosphere Explorer C satellite, is utilized to investigate properties of neutral hydrogen at altitudes below 200 km where vertical diffusion strongly affects the hydrogen distribution. Data are discussed for a set of satellite orbits during quiet geomagnetic and solar conditions in February 1974; the resultant altitude variation of the derived hydrogen concentrations applies specifically to early afternoon at low 10 5 atoms/cm 3 is observed for these conditions at 300 km. At lower altitudes the concentration profiles are interpreted in terms of vertical hydrogen flow. The resultant daytime flux in the thermosphere is estimated to be (3.2 +- 1.0) x 10 8 atoms/cm 2 s. The present observations thus support theoretical estimates and model calculations of large hydrogen flow upward from the region below 100 km. They also support the concept of daytime thermospheric loss process of greater magnitude than the traditional evaporative escape mechanism

  19. Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion.

    Science.gov (United States)

    Tanabe, Katsuaki

    2016-01-01

    We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

  20. Future outlook of hydrogen market

    International Nuclear Information System (INIS)

    Ozmen, S.; Leprince, P.

    1976-01-01

    Up to now, hydrogen has been produced from hydrocarbons for chemical uses. In the future, it will have to find a new market for itself which will depend on the development of nuclear power plants. Through the use of electric or thermal energy available during off-peak hours, water decomposition by electrolytic or thermal methods (redox cycle) could produce hydrogen, a storable and transportable gas. In addition to hydrogen consumption for chemical uses (methanol and ammonia manufacturing, petroleum fraction processing, metallurgy, etc.) plans are being drawn up to use hydrogen as a vehicle for energy [fr

  1. Steam and partial oxidation reforming options for hydrogen production from fossil fuels for PEM fuel cells

    Directory of Open Access Journals (Sweden)

    Yousri M.A. Welaya

    2012-06-01

    Full Text Available Proton exchange membrane fuel cell (PEM generates electrical power from air and from hydrogen or hydrogen rich gas mixtures. Therefore, there is an increasing interest in converting current hydrocarbon based marine fuels such as natural gas, gasoline, and diesel into hydrogen rich gases acceptable to the PEM fuel cells on board ships. Using chemical flow sheeting software, the total system efficiency has been calculated. Natural gas appears to be the best fuel for hydrogen rich gas production due to its favorable composition of lower molecular weight compounds. This paper presents a study for a 250 kW net electrical power PEM fuel cell system utilizing a partial oxidation in one case study and steam reformers in the second. This study has shown that steam-reforming process is the most competitive fuel processing option in terms of fuel processing efficiency. Partial oxidation process has proved to posses the lowest fuel processing efficiency. Among the options studied, the highest fuel processing efficiency is achieved with natural gas steam reforming system.

  2. Airborne hydrogen cyanide measurements using a chemical ionisation mass spectrometer for the plume identification of biomass burning forest fires

    Directory of Open Access Journals (Sweden)

    M. Le Breton

    2013-09-01

    Full Text Available A chemical ionisation mass spectrometer (CIMS was developed for measuring hydrogen cyanide (HCN from biomass burning events in Canada using I− reagent ions on board the FAAM BAe-146 research aircraft during the BORTAS campaign in 2011. The ionisation scheme enabled highly sensitive measurements at 1 Hz frequency through biomass burning plumes in the troposphere. A strong correlation between the HCN, carbon monoxide (CO and acetonitrile (CH3CN was observed, indicating the potential of HCN as a biomass burning (BB marker. A plume was defined as being 6 standard deviations above background for the flights. This method was compared with a number of alternative plume-defining techniques employing CO and CH3CN measurements. The 6-sigma technique produced the highest R2 values for correlations with CO. A normalised excess mixing ratio (NEMR of 3.68 ± 0.149 pptv ppbv−1 was calculated, which is within the range quoted in previous research (Hornbrook et al., 2011. The global tropospheric model STOCHEM-CRI incorporated both the observed ratio and extreme ratios derived from other studies to generate global emission totals of HCN via biomass burning. Using the ratio derived from this work, the emission total for HCN from BB was 0.92 Tg (N yr−1.

  3. Hydrogen meter prooftesting

    International Nuclear Information System (INIS)

    McCown, J.J.; Mettler, G.W.

    1976-04-01

    Two diffusion type hydrogen meters have been tested on the Prototype Applications Loop (PAL). The ANL designed unit was used to monitor hydrogen in sodium during FFTF startup and over a wide range of hydrogen concentrations resulting from chemical additions to the sodium and cover gas. A commercially available meter was added and its performance compared with the ANL unit. Details of the test work are described

  4. Report of National Research Institute for Pollution and Resources for fiscal 1979. Research on conversion of coal to petroleum, research on coal liquefaction, high pressure liquid phase hydrogenation of coal by continuous test equipment, and manufacture of coal chemicals; 1979 nendo sekitan no yuka no kenkyu / sekitan no ekika no kenkyu / renzoku shiken sochi ni yoru sekitan no koatsu ekiso suisoka bunkai / coal chemicals no seizo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-07-01

    Research was conducted on conversion of coal to petroleum for the purpose of securing substitute liquid fuel. Recovery of hydrogen from the waste gas from the conversion process was explained, as were the conversion results from various coals produced in Japan. In coal liquefaction researches with the aim of manufacturing artificial petroleum, a report was made on each of the researches, i.e., the experiment results of coal liquefaction using various catalysts, manufacture of hydrogen by water gas reaction, catalytic action against coal paste, action of mixed oil and pressure against coal paste, result of hydrogen adding test for coal paste using an intermediate scale device, test result of secondary hydrogen addition for coal liquefied oil, and the test result of continuous secondary hydrogen addition for the liquefied oil. In the manufacture of fuel oil by hydro-cracking of coal or tar, a report was made on high pressure liquid phase hydrogenation of coal using a continuous testing device. Aromatic chemicals useful as chemical materials are supposed to be obtained by cutting inter-polymerized-unit bonding to make low molecules from the chemical structure of coal, removing surrounding radicals and simplifying it. A report was also made on the experiment of manufacturing coal chemicals by combination of high pressure liquid phase hydrogenation and hydro-dealkylation. (NEDO)

  5. Thermochemical hydrogen production based on magnetic fusion

    International Nuclear Information System (INIS)

    Krikorian, O.H.; Brown, L.C.

    1982-01-01

    Conceptual design studies have been carried out on an integrated fusion/chemical plant system using a Tandem Mirror Reactor fusion energy source to drive the General Atomic Sulfur-Iodine Water-Splitting Cycle and produce hydrogen as a future feedstock for synthetic fuels. Blanket design studies for the Tandem Mirror Reactor show that several design alternatives are available for providing heat at sufficiently high temperatures to drive the General Atomic Cycle. The concept of a Joule-boosted decomposer is introduced in one of the systems investigated to provide heat electrically for the highest temperature step in the cycle (the SO 3 decomposition step), and thus lower blanket design requirements and costs. Flowsheeting and conceptual process designs have been developed for a complete fusion-driven hydrogen plant, and the information has been used to develop a plot plan for the plant and to estimate hydrogen production costs. Both public and private utility financing approaches have been used to obtain hydrogen production costs of $12-14/GJ based on July 1980 dollars

  6. Achievement report for fiscal 2000 on development of technology to recycle disintegrated waste gypsum boards; 1999 nendo kaitai haisekko board no saishigenka gijutsu kaihatsu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2001-03-01

    Investigations and researches have been made on disintegrated waste gypsum boards generated in building demolishing sites, with a target of recycling them as a raw material for boards. In the investigations, the actual status of discarding the disintegrated gypsum boards was identified, whereas the harmful substance contents such as of heavy metals were verified to be below the environmental criteria. As a method to remove impurities and foreign materials from the disintegrated waste gypsum boards, the hydration crushing method was established, in which volumetric change when hemihydrate gypsum returns to gypsum dehydrate is utilized, and bond of gypsum particles with each other and with impurities is destructed to separate them into simple substances. Furthermore, discussions were given on the reforming conditions to reform in an energy saving manner the disintegrated waste gypsum boards into high-quality large-size hemihydrate gypsum by using the wet-type process that utilizes the reversible reaction between hemihydrate gypsum and gypsum dehydrate in the disintegrated waste gypsum boards. A manufacturing process to put the recycled gypsum into practical use was also discussed. Prototype board fabrication and tests were performed by using the reformed gypsum board materials, wherein good results were obtained from all of the practical, chemical, and physical tests. (NEDO)

  7. Surface characterization and chemical analysis of bamboo substrates pretreated by alkali hydrogen peroxide.

    Science.gov (United States)

    Song, Xueping; Jiang, Yan; Rong, Xianjian; Wei, Wei; Wang, Shuangfei; Nie, Shuangxi

    2016-09-01

    The surface characterization and chemical analysis of bamboo substrates by alkali hydrogen peroxide pretreatment (AHPP) were investigated in this study. The results tended to manifest that AHPP prior to enzymatic and chemical treatment was potential for improving accessibility and reactivity of bamboo substrates. The inorganic components, organic solvent extractives and acid-soluble lignin were effectively removed by AHPP. X-ray photoelectron spectroscopy (XPS) analysis indicated that the surface of bamboo chips had less lignin but more carbohydrate after pre-treatment. Fiber surfaces became etched and collapsed, and more pores and debris on the substrate surface were observed with Scanning Electron Microscopy (SEM). Brenauer-Emmett-Teller (BET) results showed that both of pore volume and surface area were increased after AHPP. Although XRD analysis showed that AHPP led to relatively higher crystallinity, pre-extraction could overall enhance the accessibility of enzymes and chemicals into the bamboo structure. Copyright © 2016. Published by Elsevier Ltd.

  8. Static analysis of the thermochemical hydrogen production IS process for assessment of the operation parameters and the chemical properties

    International Nuclear Information System (INIS)

    Kasahara, Seiji; Onuki, Kaoru; Nomura, Mikihiro; Nakao, Shin-ichi

    2006-01-01

    A sensitivity analysis of the operation parameters and the chemical properties in the thermochemical hydrogen production IS process (iodine-sulfur process) was carried out for a static flow sheet. These parameters were evaluated by hydrogen production thermal efficiency, the mass flow rate or heat exchange based on the heat/mass balance. The most important parameters were the concentration of HI after electro-electrodialysis (EED) and the apparent transport number of protons of the cation exchange membrane in the EED cell. HI concentration operation should be operated carefully because the parameters for optimum thermal efficiency and for the optimum flow rate and heat exchange were different. For the chemical properties, composition at the inlet of the HI decomposition procedure and HI x pseudo-azeotropic composition had great effects. The HI concentration after the EED should be optimized for each composition. The order of priority for the assessment of the operation parameters and chemical properties was determined by the evaluation. (author)

  9. The prospects for hydrogen as an energy carrier: an overview of hydrogen energy and hydrogen energy systems

    International Nuclear Information System (INIS)

    Rosen, Marc A.; Koohi-Fayegh, Seama

    2016-01-01

    Hydrogen is expected to play a key role as an energy carrier in future energy systems of the world. As fossil-fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier and eventually may become the principal chemical energy carrier. When most of the world's energy sources become non-fossil based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services. In such a ''hydrogen economy,'' the two complementary energy carriers, hydrogen and electricity, are used to satisfy most of the requirements of energy consumers. A transition era will bridge the gap between today's fossil-fuel economy and a hydrogen economy, in which non-fossil-derived hydrogen will be used to extend the lifetime of the world's fossil fuels - by upgrading heavy oils, for instance - and the infrastructure needed to support a hydrogen economy is gradually developed. In this paper, the role of hydrogen as an energy carrier and hydrogen energy systems' technologies and their economics are described. Also, the social and political implications of hydrogen energy are examined, and the questions of when and where hydrogen is likely to become important are addressed. Examples are provided to illustrate key points. (orig.)

  10. Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion

    Directory of Open Access Journals (Sweden)

    Katsuaki Tanabe

    2016-01-01

    Full Text Available We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

  11. Advanced compressed hydrogen fuel storage systems

    International Nuclear Information System (INIS)

    Jeary, B.

    2000-01-01

    Dynetek was established in 1991 by a group of private investors, and since that time efforts have been focused on designing, improving, manufacturing and marketing advanced compressed fuel storage systems. The primary market for Dynetek fuel systems has been Natural Gas, however as the automotive industry investigates the possibility of using hydrogen as the fuel source solution in Alternative Energy Vehicles, there is a growing demand for hydrogen storage on -board. Dynetek is striving to meet the needs of the industry, by working towards developing a fuel storage system that will be efficient, economical, lightweight and eventually capable of storing enough hydrogen to match the driving range of the current gasoline fueled vehicles

  12. Atomic hydrogen determination in medium-pressure microwave discharge hydrogen plasmas via emission actinometry

    International Nuclear Information System (INIS)

    Geng Zicai; Xu Yong; Yang Xuefeng; Wang Weiguo; Zhu Aimin

    2005-01-01

    Atomic hydrogen plays an important role in the chemical vapour deposition of functional materials, plasma etching and new approaches to the chemical synthesis of hydrogen-containing compounds. This work reports experimental determinations of atomic hydrogen in microwave discharge hydrogen plasmas formed from the TM 01 microwave mode in an ASTeX-type reactor, via optical emission spectroscopy using Ar as an actinometer. The relative intensities of the H atom Balmer lines and Ar-750.4 nm emissions as functions of input power and gas pressure have been investigated. At an input microwave power density of 13.5 W cm -3 , the approximate hydrogen dissociation fractions calculated from electron-impact excitation and quenching cross sections in the literature, decreased from ∼0.08 to ∼0.03 as the gas pressure was increased from 5 to 25 Torr. The influences of the above cross sections, and the electron and gas temperatures of the plasmas on the determination of the hydrogen dissociation fraction data have been discussed

  13. Nitrate removal from alkaline high nitrate effluent by in situ generation of hydrogen using zinc dust

    International Nuclear Information System (INIS)

    Rajagopal, S.; Chitra, S.; Paul, Biplob

    2016-01-01

    Alkaline radioactive low level waste generated in Nuclear Fuel Cycle contains substantial amount of nitrate and needs to be treated to meet Central Pollution Control Board discharge limits of 90 mg/L in marine coastal area. Several denitrification methods like chemical treatment, electrochemical reduction, biological denitrification, ion exchange, reverse osmosis, photochemical reduction etc are followed for removal of nitrate. In effluent treatment plants where chemical treatment is carried out, chemical denitrification can be easily adapted without any additional set up. Reducing agents like zinc and aluminum are suitable for reducing nitrate in alkaline solution. Study on denitrification with zinc dust was taken up in this work. Not much work has been done with zinc dust on reduction of nitrate to nitrogen in alkaline waste with high nitrate content. In the present work, nitrate is reduced by nascent hydrogen generated in situ, caused by reaction between zinc dust and sodium hydroxide

  14. Hydrogen storage - are we making progress?

    International Nuclear Information System (INIS)

    Blair, L.; Milliken, J.; Satyapal, S.

    2004-01-01

    'Full text:' The efficient storage of hydrogen in compact, lightweight systems that allow greater than 300-mile range has been identified as one of the major technical challenges facing the practical commercialization of fuel cell power systems for light-duty vehicles. Following the hydrogen vision announced by President Bush in his 2003 State of the Union address, the U.S. Department of Energy issued a Grand Challenge, soliciting ideas from universities, national laboratories, and industry. DOE's National Hydrogen Storage Project, an aggressive and innovative research program focused on materials R and D, will be launched in Fiscal Year 2005. An intensive effort is also underway in the private sector, both in the U.S. and abroad, to meet the challenging on-board hydrogen storage requirements. A historical perspective of hydrogen storage research and development will be provided and the current DOE technical targets for hydrogen storage systems will be discussed. The state-of-the-art in hydrogen storage will be summarized and recent progress assessed. Finally future research directions and areas of technical emphasis will be described. (author)

  15. Hydrogen injection device in BWR type reactor

    International Nuclear Information System (INIS)

    Takagi, Jun-ichi; Kubo, Koji.

    1988-01-01

    Purpose: To reduce the increasing ratio of main steam system dose rate due to N-16 activity due to excess hydrogen injection in the hydrogen injection operation of BWR type reactors. Constitution: There are provided a hydrogen injection mechanism for injecting hydrogen into primary coolants of a BWR type reactor, and a chemical injection device for injecting chemicals such as methanol, which makes nitrogen radioisotopes resulted in the reactor water upon hydrogen injection non-volatile, into the pressure vessel separately from hydrogen. Injected hydrogen and the chemicals are not reacted in the feedwater system, but the reaction proceeds due to the presence of radioactive rays after the injection into the pressure vessel. Then, hydrogen causes re-combination in the downcomer portion to reduce the dissolved oxygen concentration. Meanwhile, about 70 % of the chemicals is supplied by means of a jet pump directly to the reactor core, thereby converting the chemical form of N-16 in the reactor core more oxidative (non-volatile). (Kawakami, Y.)

  16. Lignin solubilization and aqueous phase reforming for the production of aromatic chemicals and hydrogen

    NARCIS (Netherlands)

    Zakzeski, J.|info:eu-repo/dai/nl/326160256; Weckhuysen, B.M.|info:eu-repo/dai/nl/285484397

    2011-01-01

    The solubilization and aqueous phase reforming of lignin, including kraft, soda, and alcell lignin along with sugarcane bagasse, at low temperatures (T≤498 K) and pressures (P≤29 bar) is reported for the first time for the production of aromatic chemicals and hydrogen. Analysis of lignin model

  17. Hydrogen production over Au-loaded mesoporous-assembled SrTiO3 nanocrystal photocatalyst: Effects of molecular structure and chemical properties of hole scavengers

    International Nuclear Information System (INIS)

    Puangpetch, Tarawipa; Chavadej, Sumaeth; Sreethawong, Thammanoon

    2011-01-01

    Graphical abstract: Formic acid, which is the smallest and completely-dissociated water-soluble carboxylic acid, exhibited the highest hydrogen production enhancement ability over the 1 wt.% Au-loaded mesoporous-assembled SrTiO 3 nanocrystal photocatalyst. Display Omitted Research highlights: → The 1 wt.% Au-loaded mesoporous-assembled SrTiO 3 nanocrystal photocatalyst was synthesized. → The molecular structure and chemical properties of hole scavengers affected H 2 production rate. → Formic acid exhibited the highest photocatalytic H 2 production enhancement ability. -- Abstract: The hydrogen production via the photocatalytic water splitting under UV irradiation using different compounds as hole scavengers (including methanol, formic acid, acetic acid, propanoic acid, hydrochloric acid, and sulfuric acid) under a low concentration range ( 3 nanocrystal photocatalyst. The results indicated that the hydrogen production efficiency greatly depended on the molecular structure, chemical properties, and concentration of the hole scavengers. Formic acid, which is the smallest and completely-dissociated water-soluble carboxylic acid, exhibited the highest hydrogen production enhancement ability. The 2.5 vol.% aqueous formic acid solution system provided the highest photocatalytic hydrogen production rate.

  18. The impact of the board's strategy-setting role on board-management relations and hospital performance.

    Science.gov (United States)

    Büchner, Vera Antonia; Schreyögg, Jonas; Schultz, Carsten

    2014-01-01

    The appropriate governance of hospitals largely depends on effective cooperation between governing boards and hospital management. Governing boards play an important role in strategy-setting as part of their support for hospital management. However, in certain situations, this active strategic role may also generate discord within this relationship. The objective of this study is to investigate the impact of the roles, attributes, and processes of governing boards on hospital performance. We examine the impact of the governing board's strategy-setting role on board-management collaboration quality and on financial performance while also analyzing the interaction effects of board diversity and board activity level. The data are derived from a survey that was sent simultaneously to German hospitals and their associated governing board, combined with objective performance information from annual financial statements and quality reports. We use a structural equation modeling approach to test the model. The results indicate that different board characteristics have a significant impact on hospital performance (R = .37). The strategy-setting role and board-management collaboration quality have a positive effect on hospital performance, whereas the impact of strategy-setting on collaboration quality is negative. We find that the positive effect of strategy-setting on performance increases with decreasing board diversity. When board members have more homogeneous backgrounds and exhibit higher board activity levels, the negative effect of the strategy-setting on collaboration quality also increases. Active strategy-setting by a governing board may generally improve hospital performance. Diverse members of governing boards should be involved in strategy-setting for hospitals. However, high board-management collaboration quality may be compromised if managerial autonomy is too highly restricted. Consequently, hospitals should support board-management collaboration about

  19. XPS study of influence of exposure to air on thermal stability and kinetics of hydrogen decomposition of MgH{sub 2} films obtained by direct hydrogenation from gaseous phase of metallic Mg

    Energy Technology Data Exchange (ETDEWEB)

    Dobrovolsky, V.D., E-mail: dobersh@ipms.kiev.ua; Khyzhun, O.Y.; Sinelnichenko, A.K.; Ershova, O.G.; Solonin, Y.M.

    2017-02-15

    Highlights: • Air influence on thermal stability of MgH{sub 2} have been studied by XPS. • XPS spectra of MgH{sub 2} films obtained at different hydrogen pressures have been studied. • Changes in the chemical state of MgH{sub 2} films depending on time of exposure to air are analyzed. • Correlation exists between chemical surface condition of MgH{sub 2} films and their thermal stableness. • Process of hydrogen desorption from MgH{sub 2} films is studied using TDS for model samples. - Abstract: Mechanism of influence of exposure to air on thermal stability of MgH{sub 2} obtained by direct hydrogenation from the gas phase, the nature of the hydride sensitivity to the negative impact of air and the role of its surface chemical state have not been studied enough. The present article presents data of X-ray photoelectron spectroscopy (XPS) measurements of the Mg 2s, O 1s, C 1s core-level spectra of surface of hydride MgH{sub 2} films derived by gas phase hydrogenation of model samples of metallic Mg, and the evolution of changes in the chemical state of the surface of the hydride films depending on the time of exposure to air and formation conditions (hydrogen pressure and hydrogenation regime). Based on results of XPS, X-ray diffraction (XRD), and thermodesorption spectroscopy (TDS), the existence of a relationship (correlation) between chemical surface condition of hydride MgH{sub 2} films obtained at different hydrogen pressures (3.0 MPa and 11.5 MPa) and their thermal stableness and temperature of the beginning of hydride decomposition has been established.

  20. Proton exchange membrane fuel cells for electrical power generation on-board commercial airplanes.

    Energy Technology Data Exchange (ETDEWEB)

    Curgus, Dita Brigitte; Munoz-Ramos, Karina (Sandia National Laboratories, Albuquerque, NM); Pratt, Joseph William; Akhil, Abbas Ali (Sandia National Laboratories, Albuquerque, NM); Klebanoff, Leonard E.; Schenkman, Benjamin L. (Sandia National Laboratories, Albuquerque, NM)

    2011-05-01

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today's technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-did the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.

  1. Proton Exchange Membrane Fuel Cells for Electrical Power Generation On-Board Commercial Airplanes

    Energy Technology Data Exchange (ETDEWEB)

    Pratt, Joesph W. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Klebanoff, Leonard E. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Munoz-Ramos, Karina [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Akhil, Abbas A. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Curgus, Dita B. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Schenkman, Benjamin L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2011-05-01

    Deployed on a commercial airplane, proton exchange membrane fuel cells may offer emissions reductions, thermal efficiency gains, and enable locating the power near the point of use. This work seeks to understand whether on-board fuel cell systems are technically feasible, and, if so, if they offer a performance advantage for the airplane as a whole. Through hardware analysis and thermodynamic and electrical simulation, we found that while adding a fuel cell system using today’s technology for the PEM fuel cell and hydrogen storage is technically feasible, it will not likely give the airplane a performance benefit. However, when we re-did the analysis using DOE-target technology for the PEM fuel cell and hydrogen storage, we found that the fuel cell system would provide a performance benefit to the airplane (i.e., it can save the airplane some fuel), depending on the way it is configured.

  2. Experimental results and analysis on hydrogen combustion

    International Nuclear Information System (INIS)

    Dorofeev, S.B.; Efimenko, A.A.; Kochurko, A.S.; Sidorov, V.P.; Bezmelnitsin, A.V.

    1994-01-01

    The Small-Scale Development Apparatus (SSDA) was constructed to provide a preliminary set of experimental data to characterize the effect of temperature on the ability of hydrogen-air-steam-mixtures to undergo detonations and, equally important, to support design of the larger-scale High-Temperature Combustion Facility (HTCF) by providing a test bed for solution of a number of high-temperature design and operational problems. The SSDA, the central element of which is 10-cm inside diameter, 6.1-m long tubular test vessel designed to permit detonation experiments at temperatures up to 700K, was employed to study self-sustained detonations in gaseous mixtures of hydrogen, air, and steam at temperature between 300K and 650K at a fixed pressure of 0.1 MPa. Detonation cell size measurements provide clear evidence that the effect of hydrogen-air gas mixture temperature, in the range 300K to 650K, is to decrease cell size and, hence, to increase the sensitivity of the mixture to undergo detonations. The effect of steam content, at any given temperature, is to increase the cell size and, thereby, to decrease the sensitivity of stoichiometric hydrogen-air mixtures. The one-dimensional ZND model does a very good job at predicting the overall trends in the cell size data over the range of hydrogen-air-steam mixture compositions and temperature studied in the experiments. Experiments were conducted to measure the rate of hydrogen oxidation in the absence of ignition sources at temperatures of 500K and 650K, for hydrogen-air mixtures of 15% and 50%, and for a mixture of equimolar hydrogen-air and 30% steam at 650K. The rate of hydrogen oxidation was found to be significant at 650K. Reduction of hydrogen concentration by chemical reaction from 50 to 44% hydrogen, and from 15 to 11% hydrogen, were observed on a time frame of minutes. The DeSoete rate equation predicts the 50% experiment very well, but greatly underestimates the reaction rate of the lean mixtures

  3. Advancement of Systems Designs and Key Engineering Technologies for Materials Based Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    van Hassel, Bart A. [United Technologies Research Center, East Hartford, CT (United States)

    2015-09-18

    UTRC lead the development of the Simulink Framework model that enables a comparison of different hydrogen storage systems on a common basis. The Simulink Framework model was disseminated on the www.HSECoE.org website that is hosted by NREL. UTRC contributed to a better understanding of the safety aspects of the proposed hydrogen storage systems. UTRC also participated in the Failure Mode and Effect Analysis of both the chemical- and the adsorbent-based hydrogen storage system during Phase 2 of the Hydrogen Storage Engineering Center of Excellence. UTRC designed a hydrogen storage system with a reversible metal hydride material in a compacted form for light-duty vehicles with a 5.6 kg H2 storage capacity, giving it a 300 miles range. It contains a heat exchanger that enables efficient cooling of the metal hydride material during hydrogen absorption in order to meet the 3.3 minute refueling time target. It has been shown through computation that the kinetics of hydrogen absorption of Ti-catalyzed NaAlH4 was ultimately limiting the rate of hydrogen absorption to 85% of the material capacity in 3.3 minutes. An inverse analysis was performed in order to determine the material property requirements in order for a metal hydride based hydrogen storage system to meet the DOE targets. Work on metal hydride storage systems was halted after the Phase 1 to Phase 2 review due to the lack of metal hydride materials with the required material properties. UTRC contributed to the design of a chemical hydrogen storage system by developing an adsorbent for removing the impurity ammonia from the hydrogen gas, by developing a system to meter the transport of Ammonia Borane (AB) powder to a thermolysis reactor, and by developing a gas-liquid-separator (GLS) for the separation of hydrogen gas from AB slurry in silicone oil. Stripping impurities from hydrogen gas is essential for a long life of the fuel cell system on board of a vehicle. Work on solid transport of AB was halted after the

  4. Florida Hydrogen Initiative

    Energy Technology Data Exchange (ETDEWEB)

    Block, David L

    2013-06-30

    monitoring at any facility engaged in transport, handling and use of hydrogen. Development of High Efficiency Low Cost Electrocatalysts for Hydrogen Production and PEM Fuel Cell Applications ? M. Rodgers, Florida Solar Energy Center The objective of this project was to decrease platinum usage in fuel cells by conducting experiments to improve catalyst activity while lowering platinum loading through pulse electrodeposition. Optimum values of several variables during electrodeposition were selected to achieve the highest electrode performance, which was related to catalyst morphology. Understanding Mechanical and Chemical Durability of Fuel Cell Membrane Electrode Assemblies ? D. Slattery, Florida Solar Energy Center The objective of this project was to increase the knowledge base of the degradation mechanisms for membranes used in proton exchange membrane fuel cells. The results show the addition of ceria (cerium oxide) has given durability improvements by reducing fluoride emissions by an order of magnitude during an accelerated durability test. Production of Low-Cost Hydrogen from Biowaste (HyBrTec?) ? R. Parker, SRT Group, Inc., Miami, FL This project developed a hydrogen bromide (HyBrTec?) process which produces hydrogen bromide from wet-cellulosic waste and co-produces carbon dioxide. Eelectrolysis dissociates hydrogen bromide producing recyclable bromine and hydrogen. A demonstration reactor and electrolysis vessel was designed, built and operated. Development of a Low-Cost and High-Efficiency 500 W Portable PEMFC System ? J. Zheng, Florida State University, H. Chen, Bing Energy, Inc. The objectives of this project were to develop a new catalyst structures comprised of highly conductive buckypaper and Pt catalyst nanoparticles coated on its surface and to demonstrate fuel cell efficiency improvement and durability and cell cost reductions in the buckypaper based electrodes. Development of an Interdisciplinary Hydrogen and Fuel Cell Technology Academic Program ? J

  5. Mechanism of the electrochemical hydrogen reaction on smooth tungsten carbide and tungsten electrodes

    International Nuclear Information System (INIS)

    Wiesener, K.; Winkler, E.; Schneider, W.

    1985-01-01

    The course of the electrochemical hydrogen reaction on smooth tungsten-carbide electrodes in hydrogen saturated 2.25 M H 2 SO 4 follows a electrochemical sorption-desorption mechanism in the potential range of -0.4 to +0.1 V. At potentials greater than +0.1 V the hydrogen oxidation is controlled by a preliminary chemical sorption step. Concluding from the similar behaviour of tungsten-carbide and tungsten electrodes after cathodic pretreatment, different tungsten oxides should be involved in the course of the hydrogen reaction on tungsten carbide electrodes. (author)

  6. The prospects for hydrogen as an energy carrier: an overview of hydrogen energy and hydrogen energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Rosen, Marc A.; Koohi-Fayegh, Seama [Ontario Univ., Oshawa, ON (Canada). Inst. of Technology

    2016-02-15

    Hydrogen is expected to play a key role as an energy carrier in future energy systems of the world. As fossil-fuel supplies become scarcer and environmental concerns increase, hydrogen is likely to become an increasingly important chemical energy carrier and eventually may become the principal chemical energy carrier. When most of the world's energy sources become non-fossil based, hydrogen and electricity are expected to be the two dominant energy carriers for the provision of end-use services. In such a ''hydrogen economy,'' the two complementary energy carriers, hydrogen and electricity, are used to satisfy most of the requirements of energy consumers. A transition era will bridge the gap between today's fossil-fuel economy and a hydrogen economy, in which non-fossil-derived hydrogen will be used to extend the lifetime of the world's fossil fuels - by upgrading heavy oils, for instance - and the infrastructure needed to support a hydrogen economy is gradually developed. In this paper, the role of hydrogen as an energy carrier and hydrogen energy systems' technologies and their economics are described. Also, the social and political implications of hydrogen energy are examined, and the questions of when and where hydrogen is likely to become important are addressed. Examples are provided to illustrate key points. (orig.)

  7. BIG hydrogen: hydrogen technology in the oil and gas sector

    International Nuclear Information System (INIS)

    2006-01-01

    The BIG Hydrogen workshop was held in Calgary, Alberta, Canada on February 13, 2006. About 60 representatives of industry, academia and government attended this one-day technical meeting on hydrogen production for the oil and gas industry. The following themes were identified from the presentations and discussion: the need to find a BIG hydrogen replacement for Steam Methane Reformer (SMR) because of uncertainty regarding cost and availability of natural gas, although given the maturity of SMR process (reliability, known capital cost) how high will H2 prices have to rise?; need for a national strategy to link the near-term and the longer-term hydrogen production requirements, which can take hydrogen from chemical feedstock to energy carrier; and in the near-term Canada should get involved in demonstrations and build expertise in large hydrogen systems including production and carbon capture and sequestration

  8. Advanced construction materials for thermo-chemical hydrogen production from VHTR process heat

    International Nuclear Information System (INIS)

    Kosmidou, Theodora; Haehner, Peter

    2009-01-01

    The (very) high temperature reactor concept ((V)HTR) is characterized by its potential for process heat applications. The production of hydrogen by means of thermo-chemical cycles is an appealing example, since it is more efficient than electrolysis due to the direct use of process heat. The sulfur-iodine cycle is one of the best studied processes for the production of hydrogen, and solar or nuclear energy can be used as a heating source for the high temperature reaction of this process. The chemical reactions involved in the cycle are: I 2 (l) + SO 2 (g) +2 H 2 O (l) → 2HI (l) + H 2 SO 4 (l) (70-120 deg. C); H 2 SO 4 (l) → H 2 O (l) + SO 2 (g) + 1/2 O 2 (g) (800-900 deg. C); 2HI (l) → I 2 (g) + H 2 (g) (300-450 deg. C) The high temperature decomposition of sulphuric acid, which is the most endothermic reaction, results in a very aggressive chemical environment which is why suitable materials for the decomposer heat exchanger have to be identified. The class of candidate materials for the decomposer is based on SiC. In the current study, SiC based materials were tested in order to determine the residual mechanical properties (flexural strength and bending modulus, interfacial strength of brazed joints), after exposure to an SO 2 rich environment, simulating the conditions in the hydrogen production plant. Brazed SiC specimens were tested after 20, 100, 500 and 1000 hrs exposure to SO 2 rich environment at 850 o C under atmospheric pressure. The gas composition in the corrosion rig was: 9.9 H 2 O, 12.25 SO 2 , 6.13 O 2 , balance N 2 (% mol). The characterization involved: weight change monitoring, SEM microstructural analysis and four-point bending tests after exposure. Most of the specimens gained weight due to the formation of a corrosion layer as observed in the SEM. The corrosion treatment also showed an effect on the mechanical properties. In the four-point bending tests performed at room temperature and at 850 deg. C, a decrease in bending modulus with

  9. Activation of hydrogen storage materials in the Li-Mg-N-H system: Effect on storage properties

    International Nuclear Information System (INIS)

    Yang, Jun; Sudik, Andrea; Wolverton, C.

    2007-01-01

    We investigate the thermodynamics, kinetics, and capacity of the hydrogen storage reaction: Li 2 Mg(NH) 2 + 2H 2 ↔ Mg(NH 2 ) 2 + 2LiH. Starting with LiNH 2 and MgH 2 , two distinct procedures have been previously proposed for activating samples to induce the reversible storage reaction. We clarify here the impact of these two activation procedures on the resulting capacity for the Li-Mg-N-H reaction. Additionally, we measure the temperature-dependent kinetic absorption data for this hydrogen storage system. Finally, our experiments confirm the previously reported formation enthalpy (ΔH), hydrogen capacity, and pressure-composition-isotherm (PCI) data, and suggest that this system represents a kinetically (but not thermodynamically) limited system for vehicular on-board storage applications

  10. A Comprehensive Study on the Electronic State of Hydrogen in α-Phase PdH(D)x-Does a Chemical Bond Between Pd and H(D) Exist?

    Science.gov (United States)

    Dekura, Shun; Kobayashi, Hirokazu; Ikeda, Ryuichi; Maesato, Mitsuhiko; Yoshino, Haruka; Ohba, Masaaki; Ishimoto, Takayoshi; Kawaguchi, Shogo; Kubota, Yoshiki; Yoshioka, Satoru; Matsumura, Syo; Sugiyama, Takeharu; Kitagawa, Hiroshi

    2018-06-12

    The palladium(Pd)-hydrogen(H) system is one of the most famous hydrogen storage systems. Although there has been much research on β-phase PdH(D)x, we comprehensively investigated the nature of the interaction between Pd and H(D) in α-phase PdH(D)x (x H(D) chemical bond for the first time, by various in situ experimental techniques and first-principles theoretical calculations. The lattice expansion by H(D) dissolution in the α-phase lattice suggests the existence of interaction between Pd and H(D). The decrease of magnetic susceptibility and the increase of electrical resistivity indicate that the electronic states are changed by the H(D) dissolution in the α phase. In situ solid-state 1H and 2H NMR results and first-principles theoretical calculations revealed that a Pd-H(D) chemical bond exists in the α phase, but the bonding character of the Pd-H(D) chemical bond in the α phase is quite different from that in the β phase; the nature of the Pd-H(D) chemical bond in the α phase is a localized covalent bond whereas that in the β phase is a metallic bond. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. CFD analysis of bubble hydrodynamics in a fuel reactor for a hydrogen-fueled chemical looping combustion system

    International Nuclear Information System (INIS)

    Harichandan, Atal Bihari; Shamim, Tariq

    2014-01-01

    Highlights: • Computational study of the fuel reactor of chemical looping combustion technology. • The results yield better understanding of the bubble hydrodynamics in fuel reactor. • Increasing the reactor bed length increases the conversion rate. • Small oxygen carrier particles improves the conversion rate. - Abstract: This study investigates the temporal development of bubble hydrodynamics in the fuel reactor of a hydrogen-fueled chemical looping combustion (CLC) system by using a computational model. The model also investigates the molar fraction of products in gas and solid phases. The study assists in developing a better understanding of the CLC process, which has many advantages such as being a potentially promising candidate for an efficient carbon dioxide capture technology. The study employs the kinetic theory of granular flow. The reactive fluid dynamic system of the fuel reactor is customized by incorporating the kinetics of an oxygen carrier reduction into a commercial computational fluid dynamics (CFD) code. An Eulerian multiphase treatment is used to describe the continuum two-fluid model for both gas and solid phases. CaSO 4 and H 2 are used as an oxygen carrier and a fuel, respectively. The computational results are validated with the experimental and numerical results available in the open literature. The CFD simulations are found to capture the features of the bubble formation, rise and burst in unsteady and quasi-steady states very well. The results show a significant increase in the conversion rate with higher dense bed height, lower bed width, higher free board height and smaller oxygen carrier particles which upsurge an overall performance of the CLC plant

  12. Carbon Dioxide-Free Hydrogen Production with Integrated Hydrogen Separation and Storage.

    Science.gov (United States)

    Dürr, Stefan; Müller, Michael; Jorschick, Holger; Helmin, Marta; Bösmann, Andreas; Palkovits, Regina; Wasserscheid, Peter

    2017-01-10

    An integration of CO 2 -free hydrogen generation through methane decomposition coupled with hydrogen/methane separation and chemical hydrogen storage through liquid organic hydrogen carrier (LOHC) systems is demonstrated. A potential, very interesting application is the upgrading of stranded gas, for example, gas from a remote gas field or associated gas from off-shore oil drilling. Stranded gas can be effectively converted in a catalytic process by methane decomposition into solid carbon and a hydrogen/methane mixture that can be directly fed to a hydrogenation unit to load a LOHC with hydrogen. This allows for a straight-forward separation of hydrogen from CH 4 and conversion of hydrogen to a hydrogen-rich LOHC material. Both, the hydrogen-rich LOHC material and the generated carbon on metal can easily be transported to destinations of further industrial use by established transport systems, like ships or trucks. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Hydrogen determination in chemically delithiated lithium ion battery cathodes by prompt gamma activation analysis

    Science.gov (United States)

    Alvarez, Emilio, II

    2007-12-01

    Lithium ion batteries, due to their relatively high energy density, are now widely used as the power source for portable electronics. Commercial lithium ion cells currently employ layered LiCoO2 as a cathode but only 50% of its theoretical capacity can be utilized. The factors that cause the limitation are not fully established in the literature. With this perspective, prompt gamma-ray activation analysis (PGAA) has been employed to determine the hydrogen content in various oxide cathodes that have undergone chemical extraction of lithium (delithiation). The PGAA data is complemented by data obtained from atomic absorption spectroscopy (AAS), redox titration, thermogravimetric analysis (TGA), and mass spectroscopy to better understand the capacity limitations and failure mechanisms of lithium ion battery cathodes. As part of this work, the PGAA facility has been redesigned and reconstructed. The neutron and gamma-ray backgrounds have been reduced by more than an order of magnitude. Detection limits for elements have also been improved. Special attention was given to the experimental setup including potential sources of error and system calibration for the detection of hydrogen. Spectral interference with hydrogen arising from cobalt was identified and corrected for. Limits of detection as a function of cobalt mass present in a given sample are also discussed. The data indicates that while delithiated layered Li1- xCoO2, Li1-xNi 1/3Mn1/3Co1/3O2, and Li1- xNi0.5Mn0.5O2 take significant amounts of hydrogen into the lattice during deep extraction, orthorhombic Li 1-xMnO2, spinel Li1- xMn2O4, and olivine Li1- xFePO4 do not. Layered LiCoO2, LiNi 0.5Mn0.5O2, and LiNi1/3Mn1/3Co 1/3O2 have been further analyzed to assess their relative chemical instabilities while undergoing stepped chemical delithiation. Each system takes increasing amounts of protons at lower lithium contents. The differences are attributed to the relative chemical instabilities of the various cathodes

  14. Comparison of Iron and Tungsten Based Oxygen Carriers for Hydrogen Production Using Chemical Looping Reforming

    Science.gov (United States)

    Khan, M. N.; Shamim, T.

    2017-08-01

    Hydrogen production by using a three reactor chemical looping reforming (TRCLR) technology is an innovative and attractive process. Fossil fuels such as methane are the feedstocks used. This process is similar to a conventional steam-methane reforming but occurs in three steps utilizing an oxygen carrier. As the oxygen carrier plays an important role, its selection should be done carefully. In this study, two oxygen carrier materials of base metal iron (Fe) and tungsten (W) are analysed using a thermodynamic model of a three reactor chemical looping reforming plant in Aspen plus. The results indicate that iron oxide has moderate oxygen carrying capacity and is cheaper since it is abundantly available. In terms of hydrogen production efficiency, tungsten oxide gives 4% better efficiency than iron oxide. While in terms of electrical power efficiency, iron oxide gives 4.6% better results than tungsten oxide. Overall, a TRCLR system with iron oxide is 2.6% more efficient and is cost effective than the TRCLR system with tungsten oxide.

  15. Conceptual study on HTGR-IS hydrogen supply system using organic hydrides

    International Nuclear Information System (INIS)

    Terada, Atsuhiko; Noguchi, Hiroki; Takegami, Hiroaki; Kamiji, Yu; Inagaki, Yoshiyuki

    2012-02-01

    We have proposed a hydrogen supply-chain system, which is a storage/supply system of large amount of hydrogen produced by HTGR-IS hydrogen production system. The organic chemical hydride method is one of the candidate techniques in the system for hydrogen storage and transportation. In this study, properties of organic hydrides and conventional hydrogen storage/supply system were surveyed to make use of the conceptual design of the hydrogen supply system using an organic hydrides method with VHTR-IS hydrogen production process (hydrogen production: 85,400 Nm 3 /h). Conceptual specifications of the main equipments were designed for the hydrogen supply system consisting of hydrogenation and dehydrogenation process. It was also clarified the problems of hydrogen supply system, such as energy efficiency and system optimization. (author)

  16. Hydrogen storage in complex hydrides

    International Nuclear Information System (INIS)

    Lupu, D.; Biris, A. R.; Misan, I.

    2005-01-01

    Full text: Hydrogen storage is a key enabling technology for the advancement of hydrogen and fuel cell power technologies in mobile and stationary applications. A relevant role of the fuel cell powered vehicles on the market of the transportation systems will be achieved only if the research and development of on-board vehicular hydrogen storage are able to allow a driving range of at least 500 km. The on-board hydrogen storage systems are more challenging due to the space, weight and cost limitations. This range of autonomy between refueling requires materials able to store at least 6.5% weight hydrogen, available at moderate pressures, at the working temperature of the fuel cells and with acceptable cycling stability. The intensive research on the hydrogen storage in alloys and intermetallic of the LaNi 5 , FeTi or Laves phase type compounds, which started more than three decades ago did not resulted in materials of more than about 3% H storage capacities. The 7.5% H content of the Mg hydride is still of attracting interest but though the absorption has been achieved at lower temperatures by ball milling magnesium with various amounts of nickel, the desorption can not be attained at 1 bar H 2 below 280 deg. C and the kinetics of the process is too slow. In the last decade, the attention is focused on another class of compounds, the complex hydrides of aluminum with alkali metals (alanates), due to their high hydrogen content. It was found that doping with Ti-based catalysts improve the hydrogenation/dehydrogenation conditions of NaAlH 4 . Later on, it was shown that ball milling with solid state catalysts greatly improve the hydrogen desorption kinetics of NaAlH 4 , and this also helps to the rehydriding process. The hydrogen desorption from NaAlH 4 occurs in three steps, it shows a reversible storage capacity of 5.5% H and this led to further research work for a better knowledge of its application relating properties. In this work, ball milling experiments on Na

  17. Experimental study on pion capture by hydrogen bound in molecules

    International Nuclear Information System (INIS)

    Horvath, D.; Aniol, K.A.; Entezami, F.; Measday, D.F.; Noble, A.J.; Stanislaus, S.; Virtue, C.J.

    1988-08-01

    An experiment was performed at TRIUMF to study the formation of pionic hydrogen atoms and molecules in solids, particularly in groups of organic molecules of slightly different structure in order to help further clarify the problem. The nuclear capture of pions by hydrogen was measured using the charge exchange of stopped pions. The coincident photons emitted by the decaying π 0 mesons were detected by TRIUMF's two large NaI spectrometers. New experimental results were obtained for the capture probability of stopped π - mesons in the nuclei of hydrogen atoms, chemically bound in molecules of some simple hydrides, acid anhydrides, and sugar isomers. A linear relation was found between pion capture in hydrogen and melting point in sugar isomers. The pion capture probability in acid anhydrides is fairly well described by a simple atomic capture model in which the capture probability on the hydrogen dramatically increases as the hydrogen atom is separated from the strongly electronegative C 2 O 3 group. Both effects are consistent with a correlation between pion capture and electron density on hydrogen atoms. (Author) (38 refs., 4 tabs., 7 figs.)

  18. Production of Plant Phthalate and its Hydrogenated Derivative from Bio-Based Platform Chemicals.

    Science.gov (United States)

    Lu, Rui; Lu, Fang; Si, Xiaoqin; Jiang, Huifang; Huang, Qianqian; Yu, Weiqiang; Kong, Xiangtao; Xu, Jie

    2018-04-06

    Direct transformation of bio-based platform chemicals into aromatic dicarboxylic acids and their derivatives, which are widely used for the manufacture of polymers, is of significant importance for the sustainable development of the plastics industry. However, limited successful chemical processes have been reported. This study concerns a sustainable route for the production of phthalate and its hydrogenated derivative from bio-based malic acid and erythritol. The key Diels-Alder reaction is applied to build a substituted cyclohexene structure. The dehydration reaction of malic acid affords fumaric acid with 96.6 % yield, which could be used as the dienophile, and 1,3-butadiene generated in situ through erythritol deoxydehydration serves as the diene. Starting from erythritol and dibutyl fumarate, a 74.3 % yield of dibutyl trans-4-cyclohexene-1,2-dicarboxylate is obtained. The palladium-catalyzed dehydrogenation of the cycloadduct gives a 77.8 % yield of dibutyl phthalate. Dibutyl trans-cyclohexane-1,2-dicarboxylate could be formed in nearly 100 % yield under mild conditions by hydrogenation of the cycloadduct. Furthermore, fumaric acid and fumarate, with trans configurations, were found to be better dienophiles for this Diels-Alder reaction than maleic acid and maleate, with cis configuration, based on the experimental and computational results. This new route will pave the way for the production of environmental friendly plastic materials from plants. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Study on hydrogen production using the fast breeder reactors (FBR)

    International Nuclear Information System (INIS)

    Kani, Yoshio

    2003-01-01

    As the fast breeder reactor (FBR) can effectively convert uranium-238 difficult to carry out nuclear fission at thermal neutron reactors to nuclear fissionable plutonium-239 to use it remarkable upgrading of application on uranium can be performed, to be expected for sustainable energy source. And, by reuse minor actinides of long half-life nuclides in reprocessed high level wasted solutions for fuels of nuclear reactors, reduction of radioactive poison based on high level radioactive wastes was enabled. As high temperature of about 800 centigrade was required on conventional hydrogen production, by new hydrogen production technique even at operation temperature of sodium-cooled FBR it can be enabled. Here were described for new hydrogen production methods applicable to FBR on palladium membrane hydrogen separation method carrying out natural gas/steam modification at reaction temperature of about 500 centigrade, low temperature thermo-chemical method expectable simultaneous simplification of production process, and electrolysis method expected on power load balancing. (G.K.)

  20. Combustion of hydrogen-air jets in local chemical equilibrium: A guide to the CHARNAL computer program

    Science.gov (United States)

    Spalding, D. B.; Launder, B. E.; Morse, A. P.; Maples, G.

    1974-01-01

    A guide to a computer program, written in FORTRAN 4, for predicting the flow properties of turbulent mixing with combustion of a circular jet of hydrogen into a co-flowing stream of air is presented. The program, which is based upon the Imperial College group's PASSA series, solves differential equations for diffusion and dissipation of turbulent kinetic energy and also of the R.M.S. fluctuation of hydrogen concentration. The effective turbulent viscosity for use in the shear stress equation is computed. Chemical equilibrium is assumed throughout the flow.

  1. Chemical Plant Accidents in a Nuclear Hydrogen Generation Scheme

    International Nuclear Information System (INIS)

    Brown, Nicholas R.; Revankar, Shripad T.

    2011-01-01

    A high temperature nuclear reactor (HTR) could be used to drive a steam reformation plant, a coal gasification facility, an electrolysis plant, or a thermochemical hydrogen production cycle. Most thermochemical cycles are purely thermodynamic, and thus achieve high thermodynamic efficiency. HTRs produce large amounts of heat at high temperature (1100 K). Helium-cooled HTRs have many passive, or inherent, safety characteristics. This inherent safety is due to the high design basis limit of the maximum fuel temperature. Due to the severity of a potential release, containment of fission products is the single most important safety issue in any nuclear reactor facility. A HTR coupled to a chemical plant presents a complex system, due primarily to the interactive nature of both plants. Since the chemical plant acts as the heat sink for the nuclear reactor, it important to understand the interaction and feedback between the two systems. Process heat plants and HTRs are generally very different. Some of the major differences include: time constants of plants, safety standards, failure probability, and transient response. While both the chemical plant and the HTR are at advanced stages of testing individually, no serious effort has been made to understand the operation of the integrated system, especially during accident events that are initiated in the chemical plant. There is a significant lack of knowledge base regarding scaling and system integration for large scale process heat plants coupled to HTRs. Consideration of feedback between the two plants during time-dependent scenarios is absent from literature. Additionally, no conceptual studies of the accidents that could occur in either plant and impact the entire coupled system are present in literature

  2. Safety issues of nuclear production of hydrogen

    International Nuclear Information System (INIS)

    Piera, Mireia; Martinez-Val, Jose M.; Jose Montes, Ma

    2006-01-01

    Hydrogen is not an uncommon issue in Nuclear Safety analysis, particularly in relation to severe accidents. On the other hand, hydrogen is a household name in the chemical industry, particularly in oil refineries, and is also a well known chemical element currently produced by steam reforming of natural gas, and other methods (such as coal gasification). In the not-too-distant future, hydrogen will have to be produced (by chemical reduction of water) using renewable and nuclear energy sources. In particular, nuclear fission seems to offer the cheapest way to provide the primary energy in the medium-term. Safety principles are fundamental guidelines in the design, construction and operation both of hydrogen facilities and nuclear power plants. When these two technologies are integrated, a complete safety analysis must consider not only the safety practices of each industry, but any interaction that could be established between them. In particular, any accident involving a sudden energy release from one of the facilities can affect the other. Release of dangerous substances (chemicals, radiotoxic effluents) can also pose safety problems. Although nuclear-produced hydrogen facilities will need specific approaches and detailed analysis on their safety features, a preliminary approach is presented in this paper. No significant roadblocks are identified that could hamper the deployment of this new industry, but some of the hydrogen production methods will involve very demanding safety standards

  3. Physico Chemical Characteristic of Kappa Carrageenan Degraded Using Hydrogen Peroxide

    Directory of Open Access Journals (Sweden)

    Rizky Febriansyah Siregar

    2017-02-01

    Full Text Available AbstractKappa carrageenan is polysaccharide that widely used in food, pharmaceutical, cosmetic, textile and printing industries as coagulate agent, stabilizer and gelling agent. Hydrogen peroxide (H2O2 is strong oxidator to degrade polysaccharide. Hydrogen peroxide has some advantades such as cheap, easy to get and savety environment. Degradation method using hydrogen peroxide is a technology based on establishment radical hydoxile reactive that attack the glycosidic of polysaccharides as a result reducing in molecular weight of polysaccharide. The aims of this study were to analyze the effect of hydrogen peroxide concentration, temperature and degradation time to molecular weight of refined kappa carrageenan. Structural changes on kappa carrageenan degradation were characterized by viscometer, SEM and FTIR. Hydrogen peroxide concentration, temperature and degradation time were significantly reducing molecular weight and changes in the structural function of refined kappa carrageenan. The lowest molecular weight of refined kappa carrageenan degraded was obtained from the treatment 3% of hydrogen peroxide at temperature 80°C and degradation time for 4 hours.

  4. Hydrogen storage in Mg: a most promising material

    International Nuclear Information System (INIS)

    Jain, I.P.; Jain, A.; Lal, C.

    2009-01-01

    In the last one decade hydrogen has attracted worldwide interest as an energy carrier. This has generated comprehensive investigations on the technology involved and how to solve the problems of production, storage and applications of hydrogen. The interest in hydrogen as energy of the future is due to it being a clean energy, most abundant element in the universe, the lightest fuel and richest in energy per unit mass. Hydrogen as a fuel can be used to cook food, drive cars, jet planes, run factories and for all our domestic energy requirements. It can provide cheap electricity. In short, hydrogen shows the solution and also allows the progressive and non-traumatic transition of today's energy sources, towards feasible safe reliable and complete sustainable energy chains. The present article deals with the hydrogen storage in metal hydrides with particular interest in Mg as it has potential to become one of the most promising storage materials. Many metals combine chemically with Hydrogen to form a class of compounds known as Hydrides. These hydrides can discharge hydrogen as and when needed by raising their temperature or pressure. An optimum hydrogen-storage material is required to have various properties viz. high hydrogen capacity per unit mass and unit volume which determines the amount of available energy, low dissociation temperature, moderate dissociation pressure, low heat of formation in order to minimize the energy necessary for hydrogen release, low heat dissipation during the exothermic hydride formation, reversibility, limited energy loss during charge and discharge of hydrogen, fast kinetics, high stability against O 2 and moisture for long cycle life, cyclibility, low cost of recycling and charging infrastructures and high safety. So far most of the hydrogen storage alloys such as LaNi 5 , TiFe, TiMn 2 , have hydrogen storage capacities, not more than 2 wt% which is not satisfactory for practical application as per DOE Goal. A group of Mg based

  5. Effect of hydrogen coverage on hydrogenation of o-cresol on Pt(111)

    Science.gov (United States)

    Li, Yaping; Liu, Zhimin; Crossley, Steven P.; Jentoft, Friederike C.; Wang, Sanwu

    2018-06-01

    The conversion of phenolics over metal catalysts is an important process for upgrading biofuels. With density functional calculations, hydrogenation of o-cresol on the hydrogen-covered Pt(111) surface was investigated. The results show that the coverage of hydrogen plays a significant role in the reaction rate while it does not affect the reaction selectivity. The reaction barriers of the hydrogenation process leading to the formation of both 2-methyl-cyclohexanone (the intermediate product) and 2-methyl-cyclohexanol (the final product) at high H coverages (∼1 ML) are found to be smaller by 0.14-0.69 eV than those at lower H coverages (∼1/25 ML). After both hydrogen and cresol are adsorbed on Pt(111) from their initial gas phase state, the reaction energy of each hydrogenation step on the surface is also dependent on the hydrogen coverage. On the H-covered Pt(111) surface, most steps of hydrogenation involve exothermic reactions when the hydrogen coverage is high while they are endothermic reactions at low hydrogen coverages. The differences in reaction rate and reaction energy between high and low H coverages can be understood with the coverage-dependent bonding strength and configurations.

  6. Functionalization of Hydrogenated Chemical Vapour Deposition-Grown Graphene by On-Surface Chemical Reactions

    Czech Academy of Sciences Publication Activity Database

    Drogowska, Karolina; Kovaříček, Petr; Kalbáč, Martin

    2017-01-01

    Roč. 23, č. 17 (2017), s. 4073-4078 ISSN 0947-6539 R&D Projects: GA MŠk LL1301; GA MŠk(CZ) LM2015073 Grant - others:AVČR PPPLZ(CZ) L200401551 Institutional support: RVO:61388955 Keywords : functionalization * graphene * hydrogen ation * Raman spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 5.317, year: 2016

  7. Functionalization of Hydrogenated Chemical Vapour Deposition-Grown Graphene by On-Surface Chemical Reactions

    Czech Academy of Sciences Publication Activity Database

    Drogowska, Karolina; Kovaříček, Petr; Kalbáč, Martin

    2017-01-01

    Roč. 23, č. 17 (2017), s. 4073-4078 ISSN 0947-6539 R&D Projects: GA MŠk LL1301; GA MŠk(CZ) LM2015073 Grant - others:AVČR PPPLZ(CZ) L200401551 Institutional support: RVO:61388955 Keywords : functionalization * graphene * hydrogenation * Raman spectroscopy Subject RIV: CF - Physical ; Theoretical Chemistry OBOR OECD: Physical chemistry Impact factor: 5.317, year: 2016

  8. Miniaturized and green method for determination of chemical oxygen demand using UV-induced oxidation with hydrogen peroxide and single drop microextraction

    International Nuclear Information System (INIS)

    Akhoundzadeh, Jeyran; Chamsaz, Mahmoud; Costas, Marta; Lavilla, Isela; Bendicho, Carlos

    2013-01-01

    We report on a green method for the determination of low levels of chemical oxygen demand. It is based on the combination of (a) UV-induced oxidation with hydrogen peroxide, (b) headspace single-drop microextraction with in-drop precipitation, and (c) micro-turbidimetry. The generation of CO 2 after photolytic oxidation followed by its sequestration onto a microdrop of barium hydroxide gives rise to a precipitate of barium carbonate which is quantified by turbidimetry. UV-light induced oxidation was studied in the absence and presence of H 2 O 2 , ultrasound, and ferrous ion. Determinations of chemical oxygen demand were performed using potassium hydrogen phthalate as a model compound. The optimized method gives a calibration curve that is linear between 3.4 and 20 mg L −1 oxygen. The detection limit was 1.2 mg L −1 of oxygen, and the repeatability (as relative standard deviation) was around 5 %. The method was successfully applied to the determination of chemical oxygen demand in different natural waters and a synthetic wastewater. (author)

  9. Near-term markets for PEM fuel cell power modules: industrial vehicles and hydrogen recovery

    International Nuclear Information System (INIS)

    Chintawar, P.S.; Block, G.

    2004-01-01

    'Full text:' Nuvera Fuel Cells, Inc. is a global leader in the development and advancement of multifuel processing and fuel cell technology. With offices located in Italy and the USA, Nuvera is committed to advancing the commercialization of hydrogen fuel cell power modules for industrial vehicles and equipment and stationary applications by 2006, natural gas fuel cell power systems for cogeneration applications by 2007, and on-board gasoline fuel processors and fuel cell stacks for automotive applications by 2010. Nuvera Fuel Cells Europe is ISO 9001:2000 certified for 'Research, Development, Design, Production and Servicing of Fuel Cell Stacks and Fuel Cell Systems.' In the chemical industry, one of the largest operating expenses today is the cost of electricity. For example, caustic soda and chlorine are produced today using industrial membrane electrolysis which is an energy intensive process. Production of 1 metric ton of caustic soda consumes 2.5 MWh of energy. However, about 20% of the electricity consumed can be recovered by converting the hydrogen byproduct of the caustic soda production process into electricity via PEM fuel cells. The accessible market is a function of the economic value of the hydrogen whether flared, used as fuel, or as chemical. Responding to this market need, we are currently developing large hydrogen fuel cell power modules 'Forza' that use excess hydrogen to produce electricity, representing a practical economic alternative to reducing the net electricity cost. Due for commercial launch in 2006, Forza is a low-pressure, steady state, base-load power generation solution that will operate at high efficiency and 100% capacity over a 24-hour period. We believe this premise is also true for chemical and electrochemical plants and companies that convert hydrogen to electricity using renewable sources like windmills or hydropower. The second near-term market that Nuvera is developing utilizes a 5.5 kW hydrogen fueled power module 'H 2 e

  10. Hydrogen storage: state-of-the-art and future perspective

    International Nuclear Information System (INIS)

    Tzimas, E.; Filiou, C.; Peteves, S.D.; Veyret, J.B.

    2003-01-01

    The EU aims at establishing a sustainable energy supply, able to provide affordable and clean energy without increasing green house gas emissions. Hydrogen and fuel cells are seen by many as key energy system solutions for the 21. century, enabling clean and efficient production of power and heat from a broad range of primary energy sources. To be effective, there is a crucial need for well-coordinated research, development and deployment at European Level. The particular segment of hydrogen storage is one key element of the full hydrogen chain and it must meet a number of challenges before it is introduced into the global energy system. Regarding its energy characteristics, the gravimetric energy density of hydrogen is about three times higher than gasoline, but its energy content per volume is about a quarter. Therefore, the most significant problem for hydrogen (in particular for on-board vehicles) is to store sufficient -amounts of hydrogen. The volumetric energy density of hydrogen can be increased by compression or liquefaction which are both the most mature technologies. Still the energy required for both compression and liquefaction is one element to be properly assessed in considering the different pathways in particular for distribution. As far as on-board vehicle storage is concerned all possible options (compressed, liquid, metal hydrides and porous structures) have their own advantages and disadvantages with respect to weight, volume, energy efficiency, refuelling times, cost and safety aspects. To address these problems, long-term commitments to scientific excellence in research, coupled with co-ordination between the many different stakeholders, is required. In the current state-of-the-art in hydrogen storage, no single technology satisfies all of the criteria required by manufacturers and end-users, and a large number of obstacles have to be overcome. The current hydrogen storage technologies and their associated limitations/needs for improvement

  11. Women on professional society and journal editorial boards.

    Science.gov (United States)

    Morton, Melinda J; Sonnad, Seema S

    2007-07-01

    Membership on a professional medical society or journal editorial board is a marker of influence and prestige for those in academic medicine. This study presents the first comprehensive quantification of women on these boards and the implications for women in medicine. The numbers of women and men on professional society and journal editorial boards across 28 specialties (March 2004) were counted. The number of women holding multiple roles on these boards and the number of women holding top leadership positions on these boards were counted, and these proportions were compared. Three-thousand-four-hundred-seventy-three individuals on 39 professional medical society boards and 54 journal editorial boards were included. Eighty-three percent (2,884) of board members were male. Men occupied > 80% of top leadership positions on these boards. Thirty-five of the 589 women in the study held multiple roles. Anesthesiology (p women on boards in comparison to the total women in the specialty. Internal medicine, plastic surgery, cardiology and general surgery had nearly equivalent proportions; in otolaryngology and family medicine, female board members slightly exceeded the proportion of women in the field. Women's representation on society and editorial boards does not always reflect their presence in medical specialties, and it is critically lacking in certain specialties. Efforts should be made to attain parity of women leaders on these boards. Further efforts should be made to eliminate barriers to women's leadership in medicine.

  12. Dynamic Chemically Driven Dewetting, Spreading, and Self-Running of Sessile Droplets on Crystalline Silicon.

    Science.gov (United States)

    Arscott, Steve

    2016-12-06

    A chemically driven dewetting effect is demonstrated using sessile droplets of dilute hydrofluoric acid on chemically oxidized silicon wafers. The dewetting occurs as the thin oxide is slowly etched by the droplet and replaced by a hydrogen-terminated surface; the result of this is a gradual increase in the contact angle of the droplet with time. The time-varying work of adhesion is calculated from the time-varying contact angle; this corresponds to the changing chemical nature of the surface during dewetting and can be modeled by the well-known logistic (sigmoid) function often used for the modeling of restricted growth, in this case, the transition from an oxidized surface to a hydrogen-terminated silicon surface. The observation of the time-varying contact angle allows one to both measure the etch rate of the silicon oxide and estimate the hydrogenation rate as a function of HF concentration and wafer type. In addition to this, at a certain HF concentration, a self-running droplet effect is observed. In contrast, on hydrogen-terminated silicon wafers, a chemically induced spreading effect is observed using sessile droplets of nitric acid. The droplet spreading can also be modeled using a logistical function, where the restricted growth is the transition from hydrogen-terminated to a chemically induced oxidized silicon surface. The chemically driven dewetting and spreading observed here add to the methods available to study dynamic wetting (e.g., the moving three-phase contact line) of sessile droplets on surfaces. By slowing down chemical kinetics of the wetting, one is able to record the changing profile of the sessile droplet with time and gather information concerning the time-varying surface chemistry. The data also indicates a chemical interface hysteresis (CIH) that is compared to contact angle hysteresis (CAH). The approach can also be used to study the chemical etching and deposition behavior of thin films using liquids by monitoring the macroscopic

  13. The energy carrier hydrogen

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The potential of hydrogen to be used as a clean fuel for the production of heat and power, as well as for the propulsion of aeroplanes and vehicles, is described, in particular for Germany. First, attention is paid to the application of hydrogen as a basic material for the (petro)chemical industry, as an indirect energy source for (petro)chemical processes, and as a direct energy source for several purposes. Than the importance of hydrogen as an energy carrier in a large-scale application of renewable energy sources is discussed. Next an overview is given of new and old hydrogen production techniques from fossil fuels, biomass, or the electrolysis of water. Energetic applications of hydrogen in the transportation sector and the production of electric power and heat are mentioned. Brief descriptions are given of techniques to store hydrogen safely. Finally attention is paid to hydrogen research in Germany. Two hydrogen projects, in which Germany participates, are briefly dealt with: the Euro-Quebec project (production of hydrogen by means of hydropower), and the HYSOLAR project (hydrogen production by means of solar energy). 18 figs., 1 tab., 7 refs

  14. Recycling-oriented characterization of plastic frames and printed circuit boards from mobile phones by electronic and chemical imaging

    International Nuclear Information System (INIS)

    Palmieri, Roberta; Bonifazi, Giuseppe; Serranti, Silvia

    2014-01-01

    Highlights: • A recycling oriented characterization of end-of-life mobile phones was carried out. • Characterization was developed in a zero-waste-perspective, aiming to recover all the mobile phone materials. • Plastic frames and printed circuit boards were analyzed by electronic and chemical imaging. • Suitable milling/classification strategies were set up to define specialized-pre-concentrated-streams. • The proposed approach can improve the recovery of polymers, base/precious metals, rare earths and critical raw materials. - Abstract: This study characterizes the composition of plastic frames and printed circuit boards from end-of-life mobile phones. This knowledge may help define an optimal processing strategy for using these items as potential raw materials. Correct handling of such a waste is essential for its further “sustainable” recovery, especially to maximize the extraction of base, rare and precious metals, minimizing the environmental impact of the entire process chain. A combination of electronic and chemical imaging techniques was thus examined, applied and critically evaluated in order to optimize the processing, through the identification and the topological assessment of the materials of interest and their quantitative distribution. To reach this goal, end-of-life mobile phone derived wastes have been systematically characterized adopting both “traditional” (e.g. scanning electronic microscopy combined with microanalysis and Raman spectroscopy) and innovative (e.g. hyperspectral imaging in short wave infrared field) techniques, with reference to frames and printed circuit boards. Results showed as the combination of both the approaches (i.e. traditional and classical) could dramatically improve recycling strategies set up, as well as final products recovery

  15. Recycling-oriented characterization of plastic frames and printed circuit boards from mobile phones by electronic and chemical imaging

    Energy Technology Data Exchange (ETDEWEB)

    Palmieri, Roberta; Bonifazi, Giuseppe; Serranti, Silvia, E-mail: silvia.serranti@uniroma1.it

    2014-11-15

    Highlights: • A recycling oriented characterization of end-of-life mobile phones was carried out. • Characterization was developed in a zero-waste-perspective, aiming to recover all the mobile phone materials. • Plastic frames and printed circuit boards were analyzed by electronic and chemical imaging. • Suitable milling/classification strategies were set up to define specialized-pre-concentrated-streams. • The proposed approach can improve the recovery of polymers, base/precious metals, rare earths and critical raw materials. - Abstract: This study characterizes the composition of plastic frames and printed circuit boards from end-of-life mobile phones. This knowledge may help define an optimal processing strategy for using these items as potential raw materials. Correct handling of such a waste is essential for its further “sustainable” recovery, especially to maximize the extraction of base, rare and precious metals, minimizing the environmental impact of the entire process chain. A combination of electronic and chemical imaging techniques was thus examined, applied and critically evaluated in order to optimize the processing, through the identification and the topological assessment of the materials of interest and their quantitative distribution. To reach this goal, end-of-life mobile phone derived wastes have been systematically characterized adopting both “traditional” (e.g. scanning electronic microscopy combined with microanalysis and Raman spectroscopy) and innovative (e.g. hyperspectral imaging in short wave infrared field) techniques, with reference to frames and printed circuit boards. Results showed as the combination of both the approaches (i.e. traditional and classical) could dramatically improve recycling strategies set up, as well as final products recovery.

  16. The international symposium on 'chemical engineering of gas-liquid-solid catalyst reactions'

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, H

    1978-06-01

    A report on the International Symposium on ''Chemical Engineering of Gas-Liquid-Solid Catalyst Reactions'', sponsored by the University of Liege (3/2-3/78), covers papers on the hydrodynamics, modeling and simulation, operating behavior, and chemical kinetics of trickle-bed reactors; scale-up of a trickle-bed reactor for hydrotreating Kuwait vacuum distillate; experimental results obtained in trickle-bed reactors for hydroprocessing atmospheric residua, hydrogenation of methylstyrene, hydrogenation of butanone, and hydrodemetallization of petroleum residua; advantages and disadvantages of various three-phase reactor types (e.g., for the liquid-phase hydrogenation of carbon monoxide to benzene, SNG, or methanol) and hydrodynamics, mass and heat transfer, and modeling of bubble columns with suspended catalysts (slurry reactors), and their applications (e.g., in SNG and fermentation processes).

  17. Fiscal 1975 Sunshine Project research report. General research on hydrogen energy subsystems and their peripheral technologies (Research on chemical use); 1975 nendo suiso riyo subsystem no sogoteki kento to shuhen gijutsu ni kansuru kenkyu seika hokokusho. Kagaku riyo ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1976-04-15

    The whole amount of hydrogen consumption for chemical industries all over the world is estimated to be 249.7 billion Nm{sup 3} in 1974, while 367.2 billion Nm{sup 3} in 1980 roughly under a bold assumption, based on 3 current big consumption fields of ammonia production, methanol production and petroleum refining, and some promising fields in the future such as reduced iron and synthetic protein. Consumption ratios for every field are probably 54.9% in ammonia production, 30% in petroleum refining, 9.5% in methanol production and 5.6% in others in 1974, and nearly similar in 1980. However, although there are various troubles, if a large amount of methanol is used as fuel in the future, and its production plan is promoted to satisfy the demand of methanol fuel, hydrogen consumption for methanol production will increase drastically. In the future, if the production process of hydrogen as secondary fuel is established, such hydrogen also will be used for various chemical industries naturally. Research was thus made on use of oxygen as byproduct inevitably. (NEDO)

  18. New Rationales for Women on Boards

    OpenAIRE

    Choudhury, B.

    2014-01-01

    Should measures promoting women to corporate boards be solely justified in terms of economic arguments? Traditionally, such measures have tended to rely on utilitarian arguments, despite the fact that the most prominent of these arguments—the relationship between women’s presence on boards and firm financial performance—is equivocal. Conversely, this article argues that rationales for increasing women on boards should be based on both equality and economics grounds. An equality rationale is n...

  19. Modelling of the hydrogen effects on the morphogenesis of hydrogenated silicon nano-structures in a plasma reactor

    International Nuclear Information System (INIS)

    Brulin, Q.

    2006-01-01

    This work pursues the goal of understanding mechanisms related to the morphogenesis of hydrogenated silicon nano-structures in a plasma reactor through modeling techniques. Current technologies are first reviewed with an aim to understand the purpose behind their development. Then follows a summary of the possible studies which are useful in this particular context. The various techniques which make it possible to simulate the trajectories of atoms by molecular dynamics are discussed. The quantum methods of calculation of the interaction potential between chemical species are then developed, reaching the conclusion that only semi-empirical quantum methods are sufficiently fast to be able to implement an algorithm of quantum molecular dynamics on a reasonable timescale. From the tools introduced, a reflection on the nature of molecular metastable energetic states is presented for the theoretical case of the self-organized growth of a linear chain of atoms. This model - which consists of propagating the growth of a chain by the successive addition of the atom which least increases the electronic energy of the chain - shows that the Fermi level is a parameter essential to self organization during growth. This model also shows that the structure formed is not necessarily a total minimum energy structure. From all these numerical tools, the molecular growth of clusters can be simulated by using parameters from magnetohydrodynamic calculation results of plasma reactor modeling (concentrations of the species, interval between chemical reactions, energy of impact of the reagents...). The formation of silicon-hydrogen clusters is thus simulated by the successive capture of silane molecules. The structures formed in simulation at the operating temperatures of the plasma reactor predict the formation of spherical clusters constituting an amorphous silicon core covered by hydrogen. These structures are thus not in a state of minimum energy, contrary to certain experimental

  20. Progress on first-principles-based materials design for hydrogen storage.

    Science.gov (United States)

    Park, Noejung; Choi, Keunsu; Hwang, Jeongwoon; Kim, Dong Wook; Kim, Dong Ok; Ihm, Jisoon

    2012-12-04

    This article briefly summarizes the research activities in the field of hydrogen storage in sorbent materials and reports our recent works and future directions for the design of such materials. Distinct features of sorption-based hydrogen storage methods are described compared with metal hydrides and complex chemical hydrides. We classify the studies of hydrogen sorbent materials in terms of two key technical issues: (i) constructing stable framework structures with high porosity, and (ii) increasing the binding affinity of hydrogen molecules to surfaces beyond the usual van der Waals interaction. The recent development of reticular chemistry is summarized as a means for addressing the first issue. Theoretical studies focus mainly on the second issue and can be grouped into three classes according to the underlying interaction mechanism: electrostatic interactions based on alkaline cations, Kubas interactions with open transition metals, and orbital interactions involving Ca and other nontransitional metals. Hierarchical computational methods to enable the theoretical predictions are explained, from ab initio studies to molecular dynamics simulations using force field parameters. We also discuss the actual delivery amount of stored hydrogen, which depends on the charging and discharging conditions. The usefulness and practical significance of the hydrogen spillover mechanism in increasing the storage capacity are presented as well.

  1. Sustainable production of hydrogen and chemical commodities from biodiesel waste crude glycerol and cellulose by biological and catalytic processes

    OpenAIRE

    Maru, Biniam Taddele

    2013-01-01

    Hydrogen has a significant potential as clean and ‘green’ fuel of the future. Accordingly, this thesis investigated how to generate a sustainable production of hydrogen and other chemical commodities through study of: 1) Fermentative behavior of anaerobichydrogen producing microorganisms from pure glycerol and biodiesel waste crude glycerol; 2) The advantage of using a solid supportimmobilisationof microorganisms 3) The integration of the dark fermentative system with the catalytic hydrolysi...

  2. Rapid protein fold determination using secondary chemical shifts and cross-hydrogen bond 15N-13C' scalar couplings (3hbJNC')

    Energy Technology Data Exchange (ETDEWEB)

    Bonvin, Alexandre M.J.J.; Houben, Klaartje; Guenneugues, Marc; Kaptein, Robert; Boelens, Rolf [Utrecht University, Bijvoet Center for Biomolecular Research, NMR Spectroscopy (Netherlands)

    2001-11-15

    The possibility of generating protein folds at the stage of backbone assignment using structural restraints derived from experimentally measured cross-hydrogen bond scalar couplings and secondary chemical shift information is investigated using as a test case the small {alpha}/{beta} protein chymotrypsin inhibitor 2. Dihedral angle restraints for the {phi} and {psi} angles of 32 out of 64 residues could be obtained from secondary chemical shift analysis with the TALOS program (Corneliscu et al., 1999a). This information was supplemented by 18 hydrogen-bond restraints derived from experimentally measured cross-hydrogen bond {sup 3hb}J{sub NC'} coupling constants. These experimental data were sufficient to generate structures that are as close as 1.0 A backbone rmsd from the crystal structure. The fold is, however, not uniquely defined and several solutions are generated that cannot be distinguished on the basis of violations or energetic considerations. Correct folds could be identified by combining clustering methods with knowledge-based potentials derived from structural databases.

  3. Hydrogen sulfide waste treatment by microwave plasma-chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Harkness, J.B.L.; Doctor, R.D.

    1994-03-01

    A waste-treatment process that recovers both hydrogen and sulfur from industrial acid-gas waste streams is being developed to replace the Claus technology, which recovers only sulfur. The proposed process is derived from research reported in the Soviet technical literature and uses microwave (or radio-frequency) energy to initiate plasma-chemical reactions that dissociate hydrogen sulfide into elemental hydrogen and sulfur. This process has several advantages over the current Claus-plus-tail-gas-cleanup technology, which burns the hydrogen to water. The primary advantage of the proposal process is its potential for recovering and recycling hydrogen more cheaply than the direct production of hydrogen. Since unconverted hydrogen sulfide is recycled to the plasma reactor, the plasma-chemical process has the potential for sulfur recoveries in excess of 99% without the additional complexity of the tail-gas-cleanup processes associated with the Claus technology. There may also be some environmental advantages to the plasma-chemical process, because the process purge stream would primarily be the carbon dioxide and water contained in the acid-gas waste stream. Laboratory experiments with pure hydrogen sulfide have demonstrated the ability of the process to operate at or above atmospheric pressure with an acceptable hydrogen sulfide dissociation energy. Experiments with a wide range of acid-gas compositions have demonstrated that carbon dioxide and water are compatible with the plasma-chemical dissociation process and that they do not appear to create new waste-treatment problems. However, carbon dioxide does have negative impacts on the overall process. First, it decreases the hydrogen production, and second, it increases the hydrogen sulfide dissociation energy.

  4. Moderate Temperature Dense Phase Hydrogen Storage Materials within the US Department of Energy (DOE H2 Storage Program: Trends toward Future Development

    Directory of Open Access Journals (Sweden)

    Scott McWhorter

    2012-05-01

    Full Text Available Hydrogen has many positive attributes that make it a viable choice to augment the current portfolio of combustion-based fuels, especially when considering reducing pollution and greenhouse gas (GHG emissions. However, conventional methods of storing H2 via high-pressure or liquid H2 do not provide long-term economic solutions for many applications, especially emerging applications such as man-portable or stationary power. Hydrogen storage in materials has the potential to meet the performance and cost demands, however, further developments are needed to address the thermodynamics and kinetics of H2 uptake and release. Therefore, the US Department of Energy (DOE initiated three Centers of Excellence focused on developing H2 storage materials that could meet the stringent performance requirements for on-board vehicular applications. In this review, we have summarized the developments that occurred as a result of the efforts of the Metal Hydride and Chemical Hydrogen Storage Centers of Excellence on materials that bind hydrogen through ionic and covalent linkages and thus could provide moderate temperature, dense phase H2 storage options for a wide range of emerging Proton Exchange Membrane Fuel Cell (PEM FC applications.

  5. User's manual of BISHOP. A Bi-Phase, Sodium-Hydrogen-Oxygen system, chemical equilibrium calculation program

    International Nuclear Information System (INIS)

    Okano, Yasushi; Yamaguchi, Akira

    2001-07-01

    In an event of sodium leakage in liquid metal fast breeder reactors, liquid sodium flows out of piping, and droplet combustion might occur under a certain environmental condition. The combustion heat and reaction products should be evaluated in the sodium fire analysis codes for investigating the influence of the sodium leak age and fire incident. In order to analyze the reaction heat and products, the multi-phase chemical equilibrium calculation program for a sodium, oxygen and hydrogen system has been developed. The developed numerical program is named BISHOP, which denotes 'Bi-Phase, Sodium-Hydrogen-Oxygen, Chemical Equilibrium Calculation Program'. The Gibbs free energy minimization method is used because of the following advantages. Chemical species are easily added and changed. A variety of thermodynamic states, such as isothermal and isentropic changes, can be dealt with in addition to constant temperature and pressure processes. In applying the free energy minimization method to solve the multi-phase sodium reaction system, three new numerical calculation techniques are developed. One is theoretical simplification of phase description in equation system, the other is to extend the Gibbs free energy minimization method to a multi-phase system, and the last is to establish the efficient search for the minimum value. The reaction heat and products at the equilibrium state can be evaluated from the initial conditions, such as temperature, pressure and reactants, using BISHOP. This report describes the thermochemical basis of chemical equilibrium calculations, the system of equations, simplification models, and the procedure to prepare input data and usage of BISHOP. (author)

  6. A Feminist Framework for Nurses on Boards.

    Science.gov (United States)

    Sundean, Lisa J; Polifroni, E Carol

    Nurses' knowledge, skills, and expertise uniquely situate them to contribute to health care transformation as equal partners in organizational board governance. The Institute of Medicine, the 10,000 Nurses on Boards Coalition, and a growing number of nurse and health care scholars advocate nurse board leadership; however, nurses are rarely appointed as voting board members. When no room is made for nurses to take a seat at the table, the opportunity is lost to harness the power of nursing knowledge for health care transformation and social justice. No philosophical framework underpins the emerging focus on nurse board leadership. The purpose of this article is to add to the extant nursing literature by suggesting feminism as a philosophical framework for nurses on boards. Feminism contributes to the knowledge base of nursing as it relates to the expanding roles of nurses in health care transformation, policy, and social justice. Furthermore, a feminist philosophical framework for nurses on boards sets the foundation for new theory development and validates ongoing advancement of the nursing profession. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Characteristics from Recycled of Zinc Anode used as a Corrosion Preventing Material on Board Ship

    Science.gov (United States)

    Barokah, B.; Semin, S.; Kaligis, D. D.; Huwae, J.; Fanani, M. Z.; Rompas, P. T. D.

    2018-02-01

    The objective of this research is to obtain the values of chemical composition, electrochemical potential and electrochemical efficiency. Methods used were experiment with physical tests conducted in metallurgical laboratory and DNV-RP-B401 cathode protection design DNV (Det Norske Veritas) standard. The results showed that the composition of chemical as Zinc (Zn), Aluminium, Cadmium, Plumbumb, Copper and Indium is suitable of standard. The values of electrochemical potential and electrochemical efficiency were respectively. However it can be concluded that the normal meaning of recycled zinc anode with increasing melting temperature can produce zinc anode better than original zinc anode and can be used as cathode protection on board ships. This research can assist in the management of used zinc anode waste, the supply of zinc anodes for consumers at relatively low prices, and recommendations of using zinc anodes for the prevention of corrosion on board ship.

  8. Hydrogen in metals

    International Nuclear Information System (INIS)

    1986-01-01

    The report briefly describes the results of the single projects promoted by the German Council of Research (DFG). The subjects deal with diffusion, effusion, permeation and solubility of hydrogen in metals. They are interesting for many disciplines: metallurgy, physical metallurgy, metal physics, materials testing, welding engineering, chemistry, nuclear physics and solid-state physics. The research projects deal with the following interrelated subjects: solubility of H 2 in steel and effects on embrittlement, influence of H 2 on the fatigue strength of steel as well as the effect of H 2 on welded joints. The studies in solid-state research can be divided into methodological and physico-chemical studies. The methodological studies mainly comprise investigations on the analytical determination of H 2 by means of nuclear-physical reactions (e.g. the 15 N method) and the application of the Moessbauer spectroscopy. Physico-chemical problems are mainly dealt with in studies on interfacial reactions in connection with the absorption of hydrogen and on the diffusion of H 2 in different alloy systems. The properties of materials used for hydrogen storage were the subject of several research projects. 20 contributions were separately recorded for the data bank 'Energy'. (MM) [de

  9. Advisory Board on Alcoholism and Drug Abuse

    Science.gov (United States)

    State Employees Advisory Board on Alcoholism and Drug Abuse DHSS State of Alaska Home Divisions and ; Advisory Board on Alcoholism and Drug Abuse Page Content Alison Kulas Executive Director If you, a family Kulas Begins Tenure as Executive Director The Advisory Board on Alcoholism and Drug Abuse, The Alaska

  10. Electrochemical hydrogen Storage Systems

    International Nuclear Information System (INIS)

    Macdonald, Digby

    2010-01-01

    closed-loop cycle, our task was then to be able to hydrogenate the organotin halides back to their hydride form. In addition to this experimental work, a parallel project was carried out to develop a new model of electrochemical impedance spectroscopy (EIS) that could be used to define the mechanisms of the electrochemical hydrogenation reactions. The EIS technique is capable of probing complex chemical and electrochemical reactions, and our model was written into a computer code that allowed the input of experimental EIS data and the extraction of kinetic parameters based on a best-fit analysis of theoretical reaction schemes. Finally, electrochemical methods for hydrogenating organic and metallo-organic materials have been explored.

  11. Electrochemical hydrogen Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Digby Macdonald

    2010-08-09

    halides. To enable a closed-loop cycle, our task was then to be able to hydrogenate the organotin halides back to their hydride form. In addition to this experimental work, a parallel project was carried out to develop a new model of electrochemical impedance spectroscopy (EIS) that could be used to define the mechanisms of the electrochemical hydrogenation reactions. The EIS technique is capable of probing complex chemical and electrochemical reactions, and our model was written into a computer code that allowed the input of experimental EIS data and the extraction of kinetic parameters based on a best-fit analysis of theoretical reaction schemes. Finally, electrochemical methods for hydrogenating organic and metallo-organic materials have been explored.

  12. Hydrogen storage and fuel cells

    Science.gov (United States)

    Liu, Di-Jia

    2018-01-01

    Global warming and future energy supply are two major challenges facing American public today. To overcome such challenges, it is imperative to maximize the existing fuel utilization with new conversion technologies while exploring alternative energy sources with minimal environmental impact. Hydrogen fuel cell represents a next-generation energy-efficient technology in transportation and stationary power productions. In this presentation, a brief overview of the current technology status of on-board hydrogen storage and polymer electrolyte membrane fuel cell in transportation will be provided. The directions of the future researches in these technological fields, including a recent "big idea" of "H2@Scale" currently developed at the U. S. Department of Energy, will also be discussed.

  13. Effect of Wheat Straw Pretreatments and Glue Formulations on particle board properties

    International Nuclear Information System (INIS)

    Jabeen, S.; Naveed, S.; Yousaf, S.; Ramzan, N.

    2014-01-01

    In this paper, the effect of wheat straw (WS) pretreatments and glue formulations on mechanical (i.e. Compressive Strength (CS) and Impact Strength (IS)) and water resistance properties (i.e. Thickness Swelling (TS) and water absorption (WA)) of particle board have been investigated and the results have been compared with conventional wooden particleboard. Wheat straw was treated with steam available at 110 degree C and 20 psig, for the retention time of 5, 10 and 15 min. The solution of 10% HCl was also used for removing the lignin. Particleboard was prepared by bonding treated WS with four types of glue recipes of synthetic and natural binders like urea formaldehyde (UF), polyvinyl acetate (PVA), corn flour (CF) and wheat flour (WF). The particle board was formed at the hydraulic pressure and temperature of 2800 psig and 80 degree C respectively. It was observed that WS particleboard has low mechanical strength and high water resistance in comparison with conventional board. The particle board prepared with HCl cured wheat straw and glue having high urea formaldehyde and corn flour has higher CS and IS as well as low TS and WA. It may be concluded that wheat straw is a good substitute of wood for particle board while using HCl as a modifying chemical and strong binders like urea formaldehyde and corn flour. (author)

  14. Hydrogen and its challenges

    International Nuclear Information System (INIS)

    Schal, M.

    2008-01-01

    The future of hydrogen as a universal fuel is in jeopardy unless we are able to produce it through an environment-friendly way and at a competitive cost. Today almost all the hydrogen used in the world is produced by steam reforming of natural gas. This process releases 8 tonnes of CO 2 per tonne of hydrogen produced. Other means of producing hydrogen are the hydrolysis, the very high temperature hydrolysis, and the direct chemical dissociation of water, these processes are greener than steam reforming but less efficient. About one hundred buses in the world operate on fuel cells fed by hydrogen, but it appears that the first industrial use of hydrogen at great scale will be for the local generation of electricity. Globally the annual budget for research concerning hydrogen is 4.4 milliard (10 9 ) euros worldwide. (A.C.)

  15. Role of hydrogen in the chemical vapor deposition growth of MoS2 atomic layers

    Science.gov (United States)

    Li, Xiao; Li, Xinming; Zang, Xiaobei; Zhu, Miao; He, Yijia; Wang, Kunlin; Xie, Dan; Zhu, Hongwei

    2015-04-01

    Hydrogen plays a crucial role in the chemical vapor deposition (CVD) growth of graphene. Here, we have revealed the roles of hydrogen in the two-step CVD growth of MoS2. Our study demonstrates that hydrogen acts as the following: (i) an inhibitor of the thermal-induced etching effect in the continuous film growth process; and (ii) a promoter of the desulfurization reaction by decreasing the S/Mo atomic ratio and the oxidation reaction of the obtained MoSx (0 desulfurization reaction by decreasing the S/Mo atomic ratio and the oxidation reaction of the obtained MoSx (0 < x < 2) films. A high hydrogen content of more than 100% in argon forms nano-sized circle-like defects and damages the continuity and uniformity of the film. Continuous MoS2 films with a high crystallinity and a nearly perfect S/Mo atomic ratio were finally obtained after sulfurization annealing with a hydrogen content in the range of 20%-80%. This insightful understanding reveals the crucial roles of hydrogen in the CVD growth of MoS2 and paves the way for the controllable synthesis of two-dimensional materials. Electronic supplementary information (ESI) available: Low-magnification optical images; Raman spectra of 0% and 5% H2 samples; AFM characterization; Schematic of the film before and after sulfurization annealing; Schematic illustrations of two typical Raman-active phonon modes (E12g, A1g); Raman (mapping) spectra for 40% and 80% H2 samples before and after sulfurization annealing; PL spectra. See DOI: 10.1039/c5nr00904a

  16. The impact of surface composition on Tafel kinetics leading to enhanced electrochemical insertion of hydrogen in palladium

    Science.gov (United States)

    Dmitriyeva, Olga; Hamm, Steven C.; Knies, David L.; Cantwell, Richard; McConnell, Matt

    2018-05-01

    Our previous work experimentally demonstrated the enhancement of electrochemical hydrogen insertion into palladium by modifying the chemical composition of the cathode surface with Pb, Pt and Bi, referred to as surface promoters. The experiment demonstrated that an optimal combination of the surface promoters led to an increase in hydrogen fugacity of more than three orders of magnitude, while maintaining the same current density. This manuscript discusses the application of Density Functional Theory (DFT) to elucidate the thermodynamics and kinetics of observed enhancement of electrochemical hydrogen insertion into palladium. We present theoretical simulations that: (1) establish the elevation of hydrogen's chemical potential on Pb and Bi surfaces to enhance hydrogen insertion, (2) confirm the increase of a Tafel activation barrier that results in a decrease of the reaction rate at the given hydrogen overpotential, and (3) explain why the surface promoter's coverage needs to be non-uniform, namely to allow hydrogen insertion into palladium bulk while simultaneously locking hydrogen below the surface (the corking effect). The discussed DFT-based method can be used for efficient scanning of different material configurations to design a highly effective hydrogen storage system.

  17. Evaluation of the use of on-board spacecraft energy storage for electric propulsion missions

    Science.gov (United States)

    Poeschel, R. L.; Palmer, F. M.

    1983-01-01

    On-board spacecraft energy storage represents an under utilized resource for some types of missions that also benefit from using relatively high specific impulse capability of electric propulsion. This resource can provide an appreciable fraction of the power required for operating the electric propulsion subsystem in some missions. The most probable mission requirement for utilization of this energy is that of geostationary satellites which have secondary batteries for operating at high power levels during eclipse. The study summarized in this report selected four examples of missions that could benefit from use of electric propulsion and on-board energy storage. Engineering analyses were performed to evaluate the mass saved and economic benefit expected when electric propulsion and on-board batteries perform some propulsion maneuvers that would conventionally be provided by chemical propulsion. For a given payload mass in geosynchronous orbit, use of electric propulsion in this manner typically provides a 10% reduction in spacecraft mass.

  18. Hydrogen storage studies on palladium-doped carbon materials (AC, CB, CNMs) @ metal-organic framework-5.

    Science.gov (United States)

    Viditha, V; Srilatha, K; Himabindu, V

    2016-05-01

    Metal organic frameworks (MOFs) are a rapidly growing class of porous materials and are considered as best adsorbents for their high surface area and extraordinary porosity. The MOFs are synthesized by using various chemicals like triethylamine, terepthalic acid, zinc acetate dihydrate, chloroform, and dimethylformamide (DMF). Synthesized MOFs are intercalated with palladium/activated carbon, carbon black, and carbon nanomaterials by chemical reduction method for the purpose of enhancing the hydrogen adsorption capacities. We have observed that the palladium doped activated carbon on MOF-5 showed high hydrogen storage capacity. This may be due to the affinity of the palladium toward hydrogen molecule. The samples are characterized by X-ray diffraction, scanning electron microscopy (SEM), and Brunauer-Emmett-Teller (BET) surface area analysis. We have observed a clear decrease in the BET surface area and pore volume. The obtained results show a better performance for the synthesized sample. To our best knowledge, no one has reported the work on palladium-doped carbon materials (activated carbon, carbon black, carbon nanomaterials) impregnated to the metal-organic framework-5. We have attempted to synthesize carbon nanomaterials using indigenously fabricated chemical vapor deposition (CVD) unit as a support. We have observed an increase in the hydrogen storage capacities.

  19. Notification: FY 2017 Update of Proposed Key Management Challenges and Internal Control Weaknesses Confronting the U.S. Chemical Safety and Hazard Investigation Board

    Science.gov (United States)

    Jan 5, 2017. The EPA OIG is beginning work to update for fiscal year 2017 its list of proposed key management challenges and internal control weaknesses confronting the U.S. Chemical Safety and Hazard Investigation Board (CSB).

  20. Enhanced thermophilic fermentative hydrogen production from cassava stillage by chemical pretreatments.

    Science.gov (United States)

    Wang, Wen; Luo, Gang; Xie, Li; Zhou, Qi

    2013-01-01

    Acid and alkaline pretreatments for enhanced hydrogen production from cassava stillage were investigated in the present study. The result showed that acid pretreatment was suitable for enhancement of soluble carbohydrate while alkaline pretreatment stimulated more soluble total organic carbon production from cassava stillage. Acid pretreatment thereby has higher capacity to promote hydrogen production compared with alkaline pretreatment. Effects of pretreatment temperature, time and acid concentration on hydrogen production were also revealed by response surface methodology. The results showed that the increase of all factors increased the soluble carbohydrate production, whereas hydrogen production was inhibited when the factors exceeded their optimal values. The optimal conditions for hydrogen production were pretreatment temperature 89.5 °C, concentration 1.4% and time 69 min for the highest hydrogen production of 434 mL, 67% higher than raw cassava stillage.

  1. Board Size and Board Independence: A Quantitative Study on Banking Industry in Pakistan

    Directory of Open Access Journals (Sweden)

    Kashif Rashid

    2014-12-01

    Full Text Available This paper aims to investigate the relationship of board independence and board size with productivity and efficiency of the listed banks on the Karachi Stock Exchange, Pakistan. There is a lack of consensus regarding impact of corporate governance practices in correspondence to number of board members and board independence in banking sector. The derived results of the study show that there is a positive relationship between board independence and bank profitability and efficiency. Independent directors play a crucial role in providing genuine advice during executive decision making process which is an important source for improving overall corporate governance. Moreover, results regarding the role of control variables suggest a positive relationship of the total assets and deposits of the firm with the firm’s performance supporting stewardship theory in the market.

  2. Photoelectrochemical hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Rocheleau, R.E.; Miller, E.; Misra, A. [Univ. of Hawaii, Honolulu, HI (United States)

    1996-10-01

    The large-scale production of hydrogen utilizing energy provided by a renewable source to split water is one of the most ambitious long-term goals of the U.S. Department of Energy`s Hydrogen Program. One promising option to meet this goal is direct photoelectrolysis in which light absorbed by semiconductor-based photoelectrodes produces electrical power internally to split water into hydrogen and oxygen. Under this program, direct solar-to-chemical conversion efficiencies as high as 7.8 % have been demonstrated using low-cost, amorphous-silicon-based photoelectrodes. Detailed loss analysis models indicate that solar-to-chemical conversion greater than 10% can be achieved with amorphous-silicon-based structures optimized for hydrogen production. In this report, the authors describe the continuing progress in the development of thin-film catalytic/protective coatings, results of outdoor testing, and efforts to develop high efficiency, stable prototype systems.

  3. Effects of ion concentration on the hydrogen bonded structure of ...

    Indian Academy of Sciences (India)

    WINTEC

    Effects of ion concentration on the hydrogen bonded structure of water in the vicinity of ions in aqueous NaCl solutions. A NAG. 1. , D CHAKRABORTY and A CHANDRA*. Department of Chemistry, Indian Institute of Technology, Kanpur 208 016. 1. Present address: Department of Chemistry and Chemical Engineering,.

  4. 77 FR 1956 - National Science Board; Notice of Opportunity for Public Comment on the National Science Board...

    Science.gov (United States)

    2012-01-12

    ... NATIONAL SCIENCE FOUNDATION National Science Board; Notice of Opportunity for Public Comment on the National Science Board Data Policies Report AGENCY: National Science Board (NSB), NSF. ACTION: Request for public comments. SUMMARY: The National Science Board seeks comments from the public on the...

  5. Employee on Boarding Process Automation

    OpenAIRE

    Khushboo Nalband; Priyanka Jadhav; Geetanjali Salunke

    2017-01-01

    On boarding, also known as organizational socialization, plays a vital role in building the initial relationship between an organization and an employee. It also contributes to an employees’ satisfaction, better performance and greater organizational commitment thus increasing an employees’ effectiveness and productivity in his/her role. Therefore, it is essential that on boarding process of an organization is efficient and effective to improve new employees’ retention. Generally this on boar...

  6. Gender Quotas on Board of Directors

    DEFF Research Database (Denmark)

    Smith, Nina

    2013-01-01

    Beside arguments of fairness and equal opportunities, it is often argued that gender diversity on boards of directors may improve firm performance, but the empirical results are mixed and often negative. Based on the available research, gender quotas on boards of directors cannot be justified...

  7. LARGE-SCALE PRODUCTION OF HYDROGEN BY NUCLEAR ENERGY FOR THE HYDROGEN ECONOMY

    International Nuclear Information System (INIS)

    SCHULTZ, K.R.; BROWN, L.C.; BESENBRUCH, G.E.; HAMILTON, C.J.

    2003-01-01

    OAK B202 LARGE-SCALE PRODUCTION OF HYDROGEN BY NUCLEAR ENERGY FOR THE HYDROGEN ECONOMY. The ''Hydrogen Economy'' will reduce petroleum imports and greenhouse gas emissions. However, current commercial hydrogen production processes use fossil fuels and releases carbon dioxide. Hydrogen produced from nuclear energy could avoid these concerns. The authors have recently completed a three-year project for the US Department of Energy whose objective was to ''define an economically feasible concept for production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the energy source''. Thermochemical water-splitting, a chemical process that accomplishes the decomposition of water into hydrogen and oxygen, met this objective. The goal of the first phase of this study was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen and to select one for further detailed consideration. The authors selected the Sulfur-Iodine cycle, In the second phase, they reviewed all the basic reactor types for suitability to provide the high temperature heat needed by the selected thermochemical water splitting cycle and chose the helium gas-cooled reactor. In the third phase they designed the chemical flowsheet for the thermochemical process and estimated the efficiency and cost of the process and the projected cost of producing hydrogen. These results are summarized in this paper

  8. An integrated approach to hydrogen economy in Sicilian islands

    Energy Technology Data Exchange (ETDEWEB)

    Matera, Fabio V.; Sapienza, C.; Andaloro, L.; Dispensa, G.; Ferraro, M.; Antonucci, V. [Italian National Research Council, Institute of Advanced Energy Technologies ' ' Nicola Giordano' ' , salita S. Lucia sopra Contesse, 5, Messina 98126 (Italy)

    2009-08-15

    CNR-ITAE is developing several hydrogen and fuel cell demonstration and research projects, each intended to be part of a larger strategy for hydrogen communities settling in small Sicilian islands. These projects involve vehicle design, hydrogen production from renewable energy sources and methane, as well as implementation strategies to develop a hydrogen and renewable energy economy. These zero emission lightweight vehicles feature regenerative braking and advanced power electronics to increase efficiency. Moreover, to achieve a very easy-to-use technology, a very simple interface between driver and the system is under development, including fault-recovery strategies and GPS positioning for car-rental fleets. Also marine applications have been included, with tests on PEFC applied on passenger ships and luxury yacht as power system for on-board loads. In marine application, it is under study also an electrolysis hydrogen generator system using seawater as hydrogen carrier. For stationary and automotive applications, the project includes a hydrogen refuelling station powered by renewable energy (wind or/and solar) and test on fuel processors fed with methane, in order to make the power generation self-sufficient, as well as to test the technology and increase public awareness toward clean energy sources. (author)

  9. Effects of Hydrogen Ion Implantation on TiC-C Coating of Stainless Steel

    Institute of Scientific and Technical Information of China (English)

    ZHANG Rui-qian; LIU Yao-guang; HUANG Ning-kang

    2008-01-01

    Titanium carbide coatings are widely used as various wear-resistant material.The hydrogen erosion resistance of TiC-C films and the effect of hydrogen participation on TiC-C films were studied.Seventy-five percent TiC-C films are prepared on stainless steel surface by using ion mixing,where TiC-C films are deposited by rf magnetron sputtering followed by argon ion bombardment.The samples are then submitted to hydrogen ion implantation at 1.2×10-3 Pa.Characterization for the 75% TiC-C films was done with SIMS,XRD,AES,and XPS.Secondary ion mass spectroscopy (SIMS) was used to analyze hydrogen concentration variation with depth,X-Ray diffraction (XRD) was used to identify the phases,and Auger electron spectra (AES) as well as X-ray photoelectron spectra (XPS) were used to check the effects of hydrogen on shifts of chemical bonding states of C and Ti in the TiC-C films.It is found that TiC-C films on stainless steel surface can prevent hydrogen from entering stainless steel.

  10. Density functional theory study on the ionic liquid pyridinium hydrogen sulfate

    Science.gov (United States)

    Tankov, Ivaylo; Yankova, Rumyana; Genieva, Svetlana; Mitkova, Magdalena; Stratiev, Dicho

    2017-07-01

    The geometry, electronic structure and chemical reactivity of a pyridinium-based ionic liquid, pyridinium hydrogen sulfate ([H-Pyr]+[HSO4]-), have been discussed on the basis of quantum chemical density functional theory calculations using B3LYP/6-311+G(d,p) and B3LYP/6-311++G(2d,2p) approaches. The calculations indicated that [H-Pyr]+[HSO4]- exists in the form of an ion pair. A large electropositive potential was found on the pyridinium ring, while the regions of a negative electrostatic potential is linked with the lone pair of electronegative oxygen atoms in hydrogen sulfate anion ([HSO4]-). Electron transfer both within the anion, and between the anion and cation of an ion pair were described using natural bond orbital theory. The energy values of -7.1375 and -2.8801 eV were related to HOMO and LUMO orbitals, respectively.

  11. A Rechargeable Hydrogen Battery.

    Science.gov (United States)

    Christudas Dargily, Neethu; Thimmappa, Ravikumar; Manzoor Bhat, Zahid; Devendrachari, Mruthunjayachari Chattanahalli; Kottaichamy, Alagar Raja; Gautam, Manu; Shafi, Shahid Pottachola; Thotiyl, Musthafa Ottakam

    2018-04-27

    We utilize proton-coupled electron transfer in hydrogen storage molecules to unlock a rechargeable battery chemistry based on the cleanest chemical energy carrier molecule, hydrogen. Electrochemical, spectroscopic, and spectroelectrochemical analyses evidence the participation of protons during charge-discharge chemistry and extended cycling. In an era of anthropogenic global climate change and paramount pollution, a battery concept based on a virtually nonpolluting energy carrier molecule demonstrates distinct progress in the sustainable energy landscape.

  12. Carbon-free hydrogen production from low rank coal

    Science.gov (United States)

    Aziz, Muhammad; Oda, Takuya; Kashiwagi, Takao

    2018-02-01

    Novel carbon-free integrated system of hydrogen production and storage from low rank coal is proposed and evaluated. To measure the optimum energy efficiency, two different systems employing different chemical looping technologies are modeled. The first integrated system consists of coal drying, gasification, syngas chemical looping, and hydrogenation. On the other hand, the second system combines coal drying, coal direct chemical looping, and hydrogenation. In addition, in order to cover the consumed electricity and recover the energy, combined cycle is adopted as addition module for power generation. The objective of the study is to find the best system having the highest performance in terms of total energy efficiency, including hydrogen production efficiency and power generation efficiency. To achieve a thorough energy/heat circulation throughout each module and the whole integrated system, enhanced process integration technology is employed. It basically incorporates two core basic technologies: exergy recovery and process integration. Several operating parameters including target moisture content in drying module, operating pressure in chemical looping module, are observed in terms of their influence to energy efficiency. From process modeling and calculation, two integrated systems can realize high total energy efficiency, higher than 60%. However, the system employing coal direct chemical looping represents higher energy efficiency, including hydrogen production and power generation, which is about 83%. In addition, optimum target moisture content in drying and operating pressure in chemical looping also have been defined.

  13. Comparison of Chemical and Enzymatic Interesterification of Fully Hydrogenated Soybean Oil and Walnut Oil to Produce a Fat Base with Adequate Nutritional and Physical Characteristics

    Directory of Open Access Journals (Sweden)

    Mariel Farfán

    2015-01-01

    Full Text Available The optimal physical, chemical and nutritional properties of natural lipids depend on the structure and composition of triacylglycerols. However, they are not always mutually compatible. Lipid modification is a good way to give them specific functionalities, increase their oxidative stability, or improve their nutritional value. As such, chemical and enzymatic interesterification may be used to modify them and produce structured lipids. In accordance, the aim of this study is to compare chemical and enzymatic interesterifi cation of binary blends of fully hydrogenated soybean oil and walnut oil, using sodium methoxide or Lipozyme TL IM, respectively, to produce a fat base with adequate nutritional and physical characteristics. Three different mass ratios of fully hydrogenated soybean oil and walnut oil blends (20:80, 40:60 and 60:40 were interesterified and evaluated. Total interesterification was determined by the stabilization of the solid fat content. Chemical reaction of the 20:80 blend was completed in 10 min and of the 40:60 and 60:40 blends in 15 min. Enzymatically interesterified blends were stabilized in 120 min at all of the mass ratios. Complete interesterification significantly reduced the solid fat content of the blends at any composition. Chemical and enzymatically interesterified fully hydrogenated blend of soybean and walnut oil at mass ratio of 40:60 showed the plastic curve of an all-purpose-type shortening rich in polyunsaturated fatty acids, with a high linolenic acid (C18:3n3 content and with zero trans-fatty acids.

  14. Composition and partition functions of partially ionized hydrogen plasma in Non-Local Thermal Equilibrium (Non-LThE) and Non-Local Chemical Equilibrium (Non-LChE)

    International Nuclear Information System (INIS)

    Chen Kuan; Eddy, T.L.

    1993-01-01

    A GTME (Generalized MultiThermodynamic Equilibrium) plasma model is developed for plasmas in both Non-LThE (Non-Local Thermal Equilibrium) and Non-LChE (Non-Local Chemical Equilibrium). The model uses multitemperatures for thermal nonequilibrium and non-zero chemical affinities as a measure of the deviation from chemical equilibrium. The plasma is treated as an ideal gas with the Debye-Hueckel approximation employed for pressure correction. The proration method is used when the cutoff energy level is between two discrete levels. The composition and internal partition functions of a hydrogen plasma are presented for electron temperatures ranging from 5000 to 35000 K and pressures from 0.1 to 1000 kPa. Number densities of 7 different species of hydrogen plasma and internal partition functions of different energy modes (rotational, vibrational, and electronic excitation) are computed for three affinity values. The results differ from other plasma properties in that they 1) are not based on equilibrium properties; and 2) are expressed as a function of different energy distribution parameters (temperatures) within each energy mode of each species as appropriate. The computed number densities and partition functions are applicable to calculating the thermodynamic, transport, and radiation properties of a hydrogen plasma not in thermal and chemical equilibria. The nonequilibrium plasma model and plasma compositions presented in this paper are very useful to the diagnosis of high-speed and/or low-pressure plasma flows in which the assumptions of local thermal and chemical equilibrium are invalid. (orig.)

  15. Hydrogen vehicle fueling station

    Energy Technology Data Exchange (ETDEWEB)

    Daney, D.E.; Edeskuty, F.J.; Daugherty, M.A. [Los Alamos National Lab., NM (United States)] [and others

    1995-09-01

    Hydrogen fueling stations are an essential element in the practical application of hydrogen as a vehicle fuel, and a number of issues such as safety, efficiency, design, and operating procedures can only be accurately addressed by a practical demonstration. Regardless of whether the vehicle is powered by an internal combustion engine or fuel cell, or whether the vehicle has a liquid or gaseous fuel tank, the fueling station is a critical technology which is the link between the local storage facility and the vehicle. Because most merchant hydrogen delivered in the US today (and in the near future) is in liquid form due to the overall economics of production and delivery, we believe a practical refueling station should be designed to receive liquid. Systems studies confirm this assumption for stations fueling up to about 300 vehicles. Our fueling station, aimed at refueling fleet vehicles, will receive hydrogen as a liquid and dispense it as either liquid, high pressure gas, or low pressure gas. Thus, it can refuel any of the three types of tanks proposed for hydrogen-powered vehicles -- liquid, gaseous, or hydride. The paper discusses the fueling station design. Results of a numerical model of liquid hydrogen vehicle tank filling, with emphasis on no vent filling, are presented to illustrate the usefulness of the model as a design tool. Results of our vehicle performance model illustrate our thesis that it is too early to judge what the preferred method of on-board vehicle fuel storage will be in practice -- thus our decision to accommodate all three methods.

  16. Solar chemistry / hydrogen - Summary report on the research programme 2002; Forschungsprogramm Solarchemie / Wasserstoff

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    This summary report for the Swiss Federal Office of Energy (SFOE) on the solar chemistry / hydrogen research programme presents an overview of work done in these fields in Switzerland in 2002. It includes an overview of work done on 12 research and development projects and 9 pilot and demonstration projects. The volume is completed with a selection of 13 annual reports on particular topics, including transformation and storage of energy by photo-chemical, photo-electrochemical and photovoltaic means, generation of hydrogen using water splitting, solar production of zinc and calcium, catalytic synthesis, redox processes for the production of hydrogen and compressed air as a means of storing energy. Also covered are the topics of how solar chemistry can help reduce CO{sub 2} emissions and the management of the International Energy Agency's hydrogen annex 14. Further reports look at the destabilisation of metal hydride compounds, materials for sustainable energy technologies and diffusion barriers for high-pressure hydrogen tanks.

  17. Hydrogen as automotive fuel

    International Nuclear Information System (INIS)

    Dini, D.; Ciancia, A.; Pede, G.; Sglavo, V.; ENEA, Rome

    1992-01-01

    An assessment of the technical/economic feasibility of the use of hydrogen as an automotive fuel is made based on analyses of the following: the chemical- physical properties of hydrogen in relation to its use in internal combustion engines; the modifications necessary to adapt internal combustion engines to hydrogen use; hydrogen fuel injection systems - with water vapour injection, cryogenic injection, and the low or high pressure injection of hydrogen directly into the combustion chamber; the current commercialization status of hydrogen automotive fuels; energy efficiency ratings; environmental impacts; in-vehicle storage systems - involving the use of hydrides, high pressure systems and liquid hydrogen storage systems; performance in terms of pay-load ratio; autonomous operation; and operating costs. The paper concludes that, considering current costs for hydrogen fuel production, distribution and use, at present, the employment of hydrogen fuelled vehicles is feasible only in highly polluted urban environments where the innovative vehicle's air pollution abatement characteristics would justify its high operating costs as compared with those of conventional automotive alternatives

  18. Efficacy of formalin, hydrogen-peroxide, and sodium-chloride on fungal-infected rainbow-trout eggs

    Science.gov (United States)

    Schreier, Theresa M.; Rach, J.J.; Howe, G.E.

    1996-01-01

    Antifungal agents are essential for the maintenance of healthy stocks of fish and their eggs in intensive aquaculture operations. In the usa, formalin is the only fungicide approved for use in fish culture, however, hydrogen peroxide and sodium chloride have been granted low regulatory priority drug status by the united states food and drug administration (fda) and their use is allowed. We evaluated the efficacy of these fungicides for controlling fungal infections on rainbow trout eggs. A pilot study was conducted to determine the minimum water flow rate required to administer test chemicals accurately in heath incubators. A minimum water flow rate of 7.6 1 min(-1) was necessary to maintain treatment concentrations during flow-through chemical exposures, the antifungal activity of formalin, hydrogen peroxide, and sodium chloride was evaluated by treating uninfected and 10% fungal-infected (saprolegnia parasitica) rainbow trout eggs (oncorhynchus mykiss) for 15 min every other day until hatch. There were no significant differences among treatments in percent hatch or final infection for uninfected eggs receiving prophylactic chemical treatments, eggs of the negative control group (uninfected and untreated) had a mean hatch exceeding 86%, all chemical treatments conducted on the infected egg groups controlled the spread of fungus and improved hatching success compared with the positive control groups (infected and untreated), formalin treatments of 1000 and 1500 mu l 1(-1) and hydrogen peroxide treatments of 500 and 1000 mu l 1(-1) were the most effective. Sodium chloride treatments of 30000 mg 1(-1) improved fry hatch, but the compound was less effective at inhibiting fungal growths compared with hydrogen peroxide and formalin treatments.

  19. New perspectives on potential hydrogen storage materials using high pressure.

    Science.gov (United States)

    Song, Yang

    2013-09-21

    In addressing the global demand for clean and renewable energy, hydrogen stands out as the most suitable candidate for many fuel applications that require practical and efficient storage of hydrogen. Supplementary to the traditional hydrogen storage methods and materials, the high-pressure technique has emerged as a novel and unique approach to developing new potential hydrogen storage materials. Static compression of materials may result in significant changes in the structures, properties and performance that are important for hydrogen storage applications, and often lead to the formation of unprecedented phases or complexes that have profound implications for hydrogen storage. In this perspective article, 22 types of representative potential hydrogen storage materials that belong to four major classes--simple hydride, complex hydride, chemical hydride and hydrogen containing materials--were reviewed. In particular, their structures, stabilities, and pressure-induced transformations, which were reported in recent experimental works together with supporting theoretical studies, were provided. The important contextual aspects pertinent to hydrogen storage associated with novel structures and transitions were discussed. Finally, the summary of the recent advances reviewed and the insight into the future research in this direction were given.

  20. Impact of different metal turbidities on radiolytic hydrogen generation in nuclear power plants

    International Nuclear Information System (INIS)

    Kumbhar, A.G.; Belapurkar, A.D.; Venkateswaran, G.; Kishore, K.

    2005-01-01

    Radiolytic hydrogen generation on γ irradiation of turbid solutions containing metal turbidities such as titanium, nickel, iron, chromium, copper, indium, and aluminium was studied. It is suggested that the chemical reactivity of the metal in the turbid solution with e aq -/H/OH produced by radiolysis of water interferes with the recombination reactions which destroy H 2 and H 2 O 2 , thus leading to higher yield of hydrogen. The rate of generation of hydrogen and the G(H 2 ) value is related to the reactivity of the metal ion/hydroxylated species with the free radicals. (orig.)

  1. Proceedings of the DOE chemical/hydrogen energy systems contractor review

    Energy Technology Data Exchange (ETDEWEB)

    None

    1979-05-01

    This volume contains 45 papers as well as overviews of the two main project areas: the NASA Hydrogen Energy Storage Technology Project and Brookhaven National Laboratory's program on Electrolysis-Based Hydrogen Storage Systems. Forty-six project summaries are included. Individual papers were processed for inclusion in the Energy Data Base.

  2. Effects of partial hydrogenation, epoxidation, and hydroxylation on the fuel properties of fatty acid methyl esters

    Energy Technology Data Exchange (ETDEWEB)

    Wadumesthrige, Kapila; Salley, Steven O.; Ng, K.Y. Simon [Department of Chemical Engineering and Materials Science, Wayne State University, 5050 Anthony Wayne Drive, Detroit, MI 48202 (United States)

    2009-10-15

    The properties of biodiesel depend on the chemical structure of individual fatty acid methyl esters (FAME). In this work the chemical structure of fatty acid chains was modified by catalytic hydrogenation, epoxidation and hydroxylation under controlled conditions. Hydrolysis of ester functionality or oxidation of fatty acid chain was not observed during these reactions. The properties of hydrogenated FAME strongly depend on the hydrogenation time. The total saturated fatty acid (SFA) percentage increased from 29.3% to 76.2% after 2 h of hydrogenation. This hydrogenated FAME showed higher oxidation stability and higher cetane number but poor cold flow properties. Formation of trans FAME was observed during hydrogenation. Both hydroxylation and epoxidation resulted in a decrease of unsaturated fatty acid methyl ester (UFA) fraction. The percentages of total unsaturated FAME decreased 39% in the epoxidation reaction and 44% in the hydroxylation reaction. The addition of hydroxyl groups to the unsaturated regions of the fatty acid chain yields biodiesel with better cold flow properties, increased lubricity and slightly increased oxidative stability. However, epoxy FAME shows some interesting properties such as higher oxidation stability, higher cetane number and acceptable cold flow properties, which met the limits of ASTM D6751 biodiesel specifications. (author)

  3. Influence of n,γ-field fluctuations on critical hydrogen concentration in the reactor primary coolant

    International Nuclear Information System (INIS)

    Arkhipov, O.; Kabakchi, S.

    2014-01-01

    One of the problems arising in operation of the NPP with reactors VVER/PWR are the consequences of the primary coolant radiolysis, namely, generation of the oxidizing particles intensifying the equipment corrosion rate. During operation of the reactor a decrease in concentration of oxidizing radiolysis products is provided with introduction of molecular hydrogen into the coolant. In this connection, the reliable estimation of Critical Hydrogen Concentration (CHC), sufficient for suppression of formation of oxidizing radiolysis products under specific in-pile conditions (reactor radiation dose rate, temperature, coolant chemical composition) is of practical interest. Unfortunately, the experimental data on CHC in-pile determination differ essentially from the values calculated. Critical hydrogen concentration is in the region of kinetic instability of radiation-chemical system. A slight change in hydrogen concentration leads to a sharp (by several orders) change in concentration of both short-lived (OH, HO 2 ) and stable (O 2 , H 2 O 2 ) oxidizing particles. In essence, when reaching the CHC, the radiation-chemical system changes over from one stable state to another. The paper deals with the results of the computer simulation of influence of short-term n,γ- field fluctuations on changing of the radiation-chemical system from the state with low concentration of oxidizing particles over to the state with their high concentrations. It is demonstrated that for the correct calculation of CHC in the primary coolant of VVER/PWR the non-uniformity of n,γ-field in the core shall be taken into account. (author)

  4. Chemical variations in Yellowknife Bay formation sedimentary rocks analyzed by ChemCam on board the Curiosity rover on Mars

    Science.gov (United States)

    Mangold, Nicolas; Forni, Olivier; Dromart, G.; Stack, K.M.; Wiens, Roger C.; Gasnault, Olivier; Sumner, Dawn Y.; Nachon, Marion; Meslin, Pierre-Yves; Anderson, Ryan B.; Barraclough, Bruce; Bell, J.F.; Berger, G.; Blaney, D.L.; Bridges, J.C.; Calef, F.; Clark, Brian R.; Clegg, Samuel M.; Cousin, Agnes; Edgar, L.; Edgett, Kenneth S.; Ehlmann, B.L.; Fabre, Cecile; Fisk, M.; Grotzinger, John P.; Gupta, S.C.; Herkenhoff, Kenneth E.; Hurowitz, J.A.; Johnson, J. R.; Kah, Linda C.; Lanza, Nina L.; Lasue, Jeremie; Le Mouélic, S.; Lewin, Eric; Malin, Michael; McLennan, Scott M.; Maurice, S.; Melikechi, Noureddine; Mezzacappa, Alissa; Milliken, Ralph E.; Newsome, H.L.; Ollila, A.; Rowland, Scott K.; Sautter, Violaine; Schmidt, M.E.; Schroder, S.; D'Uston, C.; Vaniman, Dave; Williams, R.A.

    2015-01-01

    The Yellowknife Bay formation represents a ~5 m thick stratigraphic section of lithified fluvial and lacustrine sediments analyzed by the Curiosity rover in Gale crater, Mars. Previous works have mainly focused on the mudstones that were drilled by the rover at two locations. The present study focuses on the sedimentary rocks stratigraphically above the mudstones by studying their chemical variations in parallel with rock textures. Results show that differences in composition correlate with textures and both manifest subtle but significant variations through the stratigraphic column. Though the chemistry of the sediments does not vary much in the lower part of the stratigraphy, the variations in alkali elements indicate variations in the source material and/or physical sorting, as shown by the identification of alkali feldspars. The sandstones contain similar relative proportions of hydrogen to the mudstones below, suggesting the presence of hydrous minerals that may have contributed to their cementation. Slight variations in magnesium correlate with changes in textures suggesting that diagenesis through cementation and dissolution modified the initial rock composition and texture simultaneously. The upper part of the stratigraphy (~1 m thick) displays rocks with different compositions suggesting a strong change in the depositional system. The presence of float rocks with similar compositions found along the rover traverse suggests that some of these outcrops extend further away in the nearby hummocky plains.

  5. Industrial view of Hydrogen Energy

    International Nuclear Information System (INIS)

    Francois Jackow

    2006-01-01

    Industrial Gases Companies have been mastering Hydrogen production, distribution, safe handling and applications for several decades for a wide range of gas applications. This unique industrial background positioned these companies to play a key role in the emerging Hydrogen Energy market, which can rely, at early stage of development, on already existing infrastructure, logistics and technical know-how. Nevertheless, it is important to acknowledge that Hydrogen Energy raised specific challenges which are not totally addressed by industrial gas activities. The main difference is obviously in the final customer profile, which differs significantly from the qualified professional our industry is used to serve. A non professional end-user, operating with Hydrogen at home or on board of his family car, has to be served with intrinsically safe and user-friendly solutions that exceed by far the industrial specifications already in place. Another significant challenge is that we will need breakthroughs both in terms of products and infrastructure, with development time frame that may require several decades. The aim of this presentation is to review how a company like Air Liquide, worldwide leader already operating more than 200 large hydrogen production sites, is approaching this new Hydrogen Energy market, all along the complete supply chain from production to end-users. Our contributions to the analysis, understanding and deployment of this new Energy market, will be illustrated by the presentation of Air Liquide internal development's as well as our participation in several national and European projects. (author)

  6. Synergistic methane formation kinetics for hydrogen impact on carbon

    International Nuclear Information System (INIS)

    Haasz, A.A.; Davis, J.W.

    1986-06-01

    A physical/chemical model is presented for the reaction kinetics for methane formation from carbon, due to bombardment by energetic (∼ 100's eV) H + ions and thermal (∼ 1 eV) H 0 atoms. While the model was developed for H + and H 0 , it can be readily applied to non-hydrogenic energetic particles (ions or atoms, e.g., Ar + , He + , He) in combination with thermal (∼ 1 eV) hydrogen (again ions or atoms) impacting on carbon. Both collisional (in the case of the energetic particles) and chemical reaction processes are included. Special cases of sub-eV H 0 alone, energetic H + alone and combined H 0 plus H + were considered and fitted to experimental data. Generally good agreement was found between theoretical predictions and experimental results over the experimental flux and H + energy ranges studied (H 0 flux: 6x10 14 - 7x10 15 H 0 /cm 2 s, H + flux: 6x10 12 - 5x10 15 H + /cm 2 s, H + energy: 300 eV/H + and 1 keV/H + )

  7. Characterization of chemical vapour deposited diamond films: correlation between hydrogen incorporation and film morphology and quality

    International Nuclear Information System (INIS)

    Tang, C J; Neves, A J; Carmo, M C

    2005-01-01

    In order to tailor diamond synthesized through chemical vapour deposition (CVD) for different applications, many diamond films of different colours and variable quality were deposited by a 5 kW microwave plasma CVD reactor under different growth conditions. The morphology, quality and hydrogen incorporation of these films were characterized using scanning electron microscopy (SEM), Raman and Fourier-transform infrared (FTIR) spectroscopy, respectively. From this study, a general trend between hydrogen incorporation and film colour, morphology and quality was found. That is, as the films sorted by colour gradually become darker, ranging from white through grey to black, high magnification SEM images illustrate that the smoothness of the well defined crystalline facet gradually decreases and second nucleation starts to appear on it, indicating gradual degradation of the crystalline quality. Correspondingly, Raman spectra evidence that the diamond Raman peak at 1332 cm -1 becomes broader and the non-diamond carbon band around 1500 cm -1 starts to appear and becomes stronger, confirming increase of the non-diamond component and decrease of the phase purity of the film, while FTIR spectra show that the CH stretching band and the two CVD diamond specific peaks around 2830 cm -1 rise rapidly, and this indicates that the total amount of hydrogen incorporated into the film increases significantly

  8. Storage and characterization of the hydrogen in mixed oxides on base of cerium-nickel and zirconium or the aluminium

    International Nuclear Information System (INIS)

    Debeusscher, S.

    2008-12-01

    The mixed oxides based on cerium-nickel and zirconium or aluminium are able to store large quantities of hydrogen, To determine nature, reactivity and properties of hydrogen species (spill-over, direct desorption), the solid were studied by different physicochemical techniques in the dried, calcined and partially reduced states: XRD, porosity, TGA, TPR, TPA, TPD, chemical titration and inelastic neutron scattering (INS). Solids are mainly meso-porous with a common pore size at 4 nm, They are constituted of CeO 2 phase, Ce-Ni or Ce-Ni-Zr solid solution and of Ni(OH) 2 in the dried state and NiO in the calcined state. The Ni species are in various environments and the strong interactions between the cations in solid solution and at different particles interface influence their reducibility and the creation of anionic vacancies. Activation in H 2 in temperature is determining for hydrogen storage in the solid while calcination step is not necessary. INS Analyses evidence that the hydrogen species inserted during treatment in H 2 are H + (OH - ), hydride H - and H * (metallic nickel) species, present in various chemical environments, in particular for hydride species. All kinds of hydrogen species participate to the reaction during the chemical titration in agreement with the proposed hydrogenation mechanism. The study of the adsorption of hydrogen shows that this step is fast and in quantity of the same order as that measured by chemical titration. The direct desorption of H 2 is very low, linked to the presence of hydrogen in interaction with metallic nickel (H *- .). Desorption of water is also observed, in parallel, corresponding to the elimination of groups. The hydride species are not desorbed. These various observations allow connecting hydrogen species properties with their localization in the structure and to model active sites. (author)

  9. Modelling of the hydrogen effects on the morphogenesis of hydrogenated silicon nano-structures in a plasma reactor; Modelisation des effets de l'hydrogene sur la morphogenese des nanostructures de silicium hydrogene dans un reacteur plasma

    Energy Technology Data Exchange (ETDEWEB)

    Brulin, Q

    2006-01-15

    This work pursues the goal of understanding mechanisms related to the morphogenesis of hydrogenated silicon nano-structures in a plasma reactor through modeling techniques. Current technologies are first reviewed with an aim to understand the purpose behind their development. Then follows a summary of the possible studies which are useful in this particular context. The various techniques which make it possible to simulate the trajectories of atoms by molecular dynamics are discussed. The quantum methods of calculation of the interaction potential between chemical species are then developed, reaching the conclusion that only semi-empirical quantum methods are sufficiently fast to be able to implement an algorithm of quantum molecular dynamics on a reasonable timescale. From the tools introduced, a reflection on the nature of molecular metastable energetic states is presented for the theoretical case of the self-organized growth of a linear chain of atoms. This model - which consists of propagating the growth of a chain by the successive addition of the atom which least increases the electronic energy of the chain - shows that the Fermi level is a parameter essential to self organization during growth. This model also shows that the structure formed is not necessarily a total minimum energy structure. From all these numerical tools, the molecular growth of clusters can be simulated by using parameters from magnetohydrodynamic calculation results of plasma reactor modeling (concentrations of the species, interval between chemical reactions, energy of impact of the reagents...). The formation of silicon-hydrogen clusters is thus simulated by the successive capture of silane molecules. The structures formed in simulation at the operating temperatures of the plasma reactor predict the formation of spherical clusters constituting an amorphous silicon core covered by hydrogen. These structures are thus not in a state of minimum energy, contrary to certain experimental

  10. The hydrogen 700 project - 700 Bar Co

    International Nuclear Information System (INIS)

    Gambone, L.; Webster, C.

    2004-01-01

    'Full text:' Major automotive companies, including DaimlerChrysler, Ford, Hyundai, Nissan, PSA Peugeot-Citroen, and Toyota, are co-operating in the Hydrogen 700 project at Powertech to establish a global basis for high pressure hydrogen fuel systems for vehicles. The fuel systems will store compressed hydrogen on-board at pressures up to 700 bar (10,000psi). It is anticipated that the 700 bar storage pressure will provide hydrogen powered vehicles with a range comparable to the range of petroleum-fueled vehicles. The Hydrogen 700 project has contracted world leaders in high pressure technologies to provide 700 bar fuel system components for evaluation. The data from these tests will be used as the basis for the development of relevant standards and regulations. In a development that complements the Hydrogen 700 project, Powertech Labs has established the world's first 700 bar hydrogen station for fast filling operations. This prototype station will be used to evaluate the performance of the 700 bar vehicle fuel system components. The presentation will provide an overview of the Hydrogen 700 project. Safety issues surrounding the use of compressed hydrogen gas as a vehicle fuel, as well as the use of higher storage pressures, will be reviewed. Test data involving the fire testing of vehicles containing hydrogen fuel systems will be presented. The project is intended to result in the introduction of 700 bar fuel systems in the next generation of hydrogen powered vehicles. (author)

  11. C1 Chemistry for the Production of Ultra-Clean Liquid Transportation Fuels and Hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Gerald P. Huffman

    2005-03-31

    Faculty and students from five universities--the University of Kentucky, University of Pittsburgh, University of Utah, West Virginia University, and Auburn University--are collaborating in a research program to develop C1 chemistry processes to produce ultra-clean liquid transportation fuels and hydrogen, the zero-emissions transportation fuel of the future. The feedstocks contain one carbon atom per molecular unit. They include synthesis gas (syngas), a mixture of carbon monoxide and hydrogen produced by coal gasification or reforming of natural gas, methane, methanol, carbon dioxide, and carbon monoxide. An important objective is to develop C1 technology for the production of liquid transportation fuel and hydrogen from domestically plentiful resources such as coal, coalbed methane, and natural gas. An Industrial Advisory Board with representatives from Chevron-Texaco, Eastman Chemical, Conoco-Phillips, the Air Force Research Laboratory, the U.S. Army National Automotive Center (Tank & Automotive Command--TACOM), and Tier Associates provides guidance on the practicality of the research. The current report presents results obtained in this research program during the six months of the subject contract from October 1, 2002 through March 31, 2003. The results are presented in thirteen detailed reports on research projects headed by various faculty members at each of the five CFFS Universities. Additionally, an Executive Summary has been prepared that summarizes the principal results of all of these projects during the six-month reporting period.

  12. On-Board Mining in the Sensor Web

    Science.gov (United States)

    Tanner, S.; Conover, H.; Graves, S.; Ramachandran, R.; Rushing, J.

    2004-12-01

    On-board data mining can contribute to many research and engineering applications, including natural hazard detection and prediction, intelligent sensor control, and the generation of customized data products for direct distribution to users. The ability to mine sensor data in real time can also be a critical component of autonomous operations, supporting deep space missions, unmanned aerial and ground-based vehicles (UAVs, UGVs), and a wide range of sensor meshes, webs and grids. On-board processing is expected to play a significant role in the next generation of NASA, Homeland Security, Department of Defense and civilian programs, providing for greater flexibility and versatility in measurements of physical systems. In addition, the use of UAV and UGV systems is increasing in military, emergency response and industrial applications. As research into the autonomy of these vehicles progresses, especially in fleet or web configurations, the applicability of on-board data mining is expected to increase significantly. Data mining in real time on board sensor platforms presents unique challenges. Most notably, the data to be mined is a continuous stream, rather than a fixed store such as a database. This means that the data mining algorithms must be modified to make only a single pass through the data. In addition, the on-board environment requires real time processing with limited computing resources, thus the algorithms must use fixed and relatively small amounts of processing time and memory. The University of Alabama in Huntsville is developing an innovative processing framework for the on-board data and information environment. The Environment for On-Board Processing (EVE) and the Adaptive On-board Data Processing (AODP) projects serve as proofs-of-concept of advanced information systems for remote sensing platforms. The EVE real-time processing infrastructure will upload, schedule and control the execution of processing plans on board remote sensors. These plans

  13. Impurity effects of hydrogen isotope retention on boronized wall in LHD

    International Nuclear Information System (INIS)

    Oya, Yasuhisa; Okuno, Kenji; Ashikawa, Naoko; Nishimura, Kiyohiko; Sagara, Akio

    2010-11-01

    The impurity effect on hydrogen isotopes retention in the boron film deposited in LHD was evaluated by means of XPS and TDS. It was found that the impurity concentrations in boron film were increased after H-H main plasma exposure in LHD. The ratio of hydrogen retention trapped by impurity to total hydrogen retention during H-H main plasma exposure was reached to 70%, although that of deuterium retention by impurity in D 2 + implanted LHD-boron film was about 35%. In addition, the dynamic chemical sputtering of hydrogen isotopes with impurity as the form of water and / or hydrocarbons was occurred by energetic hydrogen isotopes irradiation. It was expected that the enhancement of impurity concentration during plasma exposure in LHD would induce the dynamic formation of volatile molecules and their re-emission to plasma. These facts would prevent stable plasma operation in LHD, concluding that the dynamic impurity behavior in boron film during plasma exposure is one of key issues for the steady-state plasma operation in LHD. (author)

  14. Production of hydrogen gas from novel chemical hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Aiello, R.; Matthews, M.A. [South Carolina Univ., Chemical Engineering Dept., Columbia, SC (United States); Reger, D.L.; Collins, J.E. [South Carolina Univ., Chemistry and Biochemistry Dept., Columbia, SC (United States)

    1998-12-01

    Six ligand-stabilized complexes have been synthesized and tested for use as hydrogen storage media for portable fuel cell applications. The new hydrides are: [HC(3,5-Me{sub 2}pz){sub 3}]LiBH{sub 4} (1), [[H{sub 2}C(3,5-Me{sub 2}pz){sub 2}]LiBH{sub 4})]{sub 2} (2) (pz = pyrazolyl), [(TMEDA)Li(BH{sub 4})]{sub 2} (3) (TMEDA (CH{sub 3}){sub 2}NCH{sub 2}CH{sub 2}N(CH{sub 3}){sub 2}), [HC(pz){sub 3}]LiBH{sub 4} (4), [[H{sub 2}C(pz){sub 2}]Li(BH{sub 4})]{sub 2} (5) and Mg(BH{sub 4}){sub 2}3THF (6) (THF = tetrahydrofuran). Hydrolysis reactions of the compounds liberate hydrogen in quantities which range from 56 to 104 ({+-}5%) of the theoretical yield. Gas chromatographic analysis of the product gases from these reactions indicate that hydrogen is the only gas produced. Thermally initiated reactions of the novel compounds with NH{sub 4}Cl were unsuccessful. Although the amount of hydrogen energy which can be theoretically obtained per unit weight is lower than that of the classical hydrides such as LiBH{sub 4} and NaBH{sub 4}, the reactions are less violent and hydrolysis of compounds 1, 2, 4, 5 and 6 releases less heat per mole of hydrogen generated. (Author)

  15. Hydrogen-Assisted IC Engine Combustion as a Route to Hydrogen Implementation

    Energy Technology Data Exchange (ETDEWEB)

    Andre Boehman; Daniel Haworth

    2008-09-30

    composition and utilization through laboratory studies of spark-ignition engine operation on H{sub 2}-NG and numerical simulation of the impact of hydrogen blending on the physical and chemical processes within the engine; and (2) Examination of hydrogen-assisted combustion in advanced compression-ignition engine processes. To that end, numerical capabilities were applied to the study of hydrogen assisted combustion and experimental facilities were developed to achieve the project objectives.

  16. Hydrogen exchange rate of tyrosine hydroxyl groups in proteins as studied by the deuterium isotope effect on C(zeta) chemical shifts.

    Science.gov (United States)

    Takeda, Mitsuhiro; Jee, Jungoo; Ono, Akira Mei; Terauchi, Tsutomu; Kainosho, Masatsune

    2009-12-30

    We describe a new NMR method for monitoring the individual hydrogen exchange rates of the hydroxyl groups of tyrosine (Tyr) residues in proteins. The method utilizes (2S,3R)-[beta(2),epsilon(1,2)-(2)H(3);0,alpha,beta,zeta-(13)C(4);(15)N]-Tyr, zeta-SAIL Tyr, to detect and assign the (13)C(zeta) signals of Tyr rings efficiently, either by indirect (1)H-detection through 7-8 Hz (1)H(delta)-(13)C(zeta) spin couplings or by direct (13)C(zeta) observation. A comparison of the (13)C(zeta) chemical shifts of three Tyr residues of an 18.2 kDa protein, EPPIb, dissolved in H(2)O and D(2)O, revealed that all three (13)C(zeta) signals in D(2)O appeared at approximately 0.13 ppm ( approximately 20 Hz at 150.9 MHz) higher than those in H(2)O. In a H(2)O/D(2)O (1:1) mixture, however, one of the three signals for (13)C(zeta) appeared as a single peak at the averaged chemical shifts, and the other two appeared as double peaks at exactly the same chemical shifts in H(2)O and D(2)O, in 50 mM phosphate buffer (pH 6.6) at 40 degrees C. These three peaks were assigned to Tyr-36, Tyr-120, and Tyr-30, from the lower to higher chemical shifts, respectively. The results indicate that the hydroxyl proton of Tyr-120 exchanges faster than a few milliseconds, whereas those of Tyr-30 and Tyr-36 exchange more slowly. The exchange rate of the Tyr-30 hydroxyl proton, k(ex), under these conditions was determined by (13)C NMR exchange spectroscopy (EXSY) to be 9.2 +/- 1.1 s(-1). The Tyr-36 hydroxyl proton, however, exchanges too slowly to be determined by EXSY. These profound differences among the hydroxyl proton exchange rates are closely related to their relative solvent accessibility and the hydrogen bonds associated with the Tyr hydroxyl groups in proteins.

  17. Ford/BASF/UM Activities in Support of the Hydrogen Storage Engineering Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Veenstra, Mike [Ford Motor Company, Dearborn, MI (United States); Purewal, Justin [Ford Motor Company, Dearborn, MI (United States); Xu, Chunchuan [Ford Motor Company, Dearborn, MI (United States); Yang, Jun [Ford Motor Company, Dearborn, MI (United States); Blaser, Rachel [Ford Motor Company, Dearborn, MI (United States); Sudik, Andrea [Ford Motor Company, Dearborn, MI (United States); Siegel, Don [Univ. of Michigan, Ann Arbor, MI (United States); Ming, Yang [Univ. of Michigan, Ann Arbor, MI (United States); Liu, Dong' an [Univ. of Michigan, Ann Arbor, MI (United States); Chi, Hang [Univ. of Michigan, Ann Arbor, MI (United States); Gaab, Manuela [BASF SE, Ludwigshafen (Germany); Arnold, Lena [BASF SE, Ludwigshafen (Germany); Muller, Ulrich [BASF SE, Ludwigshafen (Germany)

    2015-06-30

    Widespread adoption of hydrogen as a vehicular fuel depends critically on the development of low-cost, on-board hydrogen storage technologies capable of achieving high energy densities and fast kinetics for hydrogen uptake and release. As present-day technologies -- which rely on physical storage methods such as compressed hydrogen -- are incapable of attaining established Department of Energy (DOE) targets, development of materials-based approaches for storing hydrogen have garnered increasing attention. Material-based storage technologies have potential to store hydrogen beyond twice the density of liquid hydrogen. To hasten development of these ‘hydride’ materials, the DOE previously established three centers of excellence for materials storage R&D associated with the key classes of materials: metal hydrides, chemical hydrogen, and adsorbents. While these centers made progress in identifying new storage materials, the challenges associated with the engineering of the system around a candidate storage material are in need of further advancement. In 2009 the DOE established the Hydrogen Storage Engineering Center of Excellence with the objective of developing innovative engineering concepts for materials-based hydrogen storage systems. As a partner in the Hydrogen Storage Engineering Center of Excellence, the Ford-UM-BASF team conducted a multi-faceted research program that addresses key engineering challenges associated with the development of materials-based hydrogen storage systems. First, we developed a novel framework that allowed for a material-based hydrogen storage system to be modeled and operated within a virtual fuel cell vehicle. This effort resulted in the ability to assess dynamic operating parameters and interactions between the storage system and fuel cell power plant, including the evaluation of performance throughout various drive cycles. Second, we engaged in cost modeling of various incarnations of the storage systems. This analysis

  18. Studies on hydrogen separation membrane for IS process. Membrane preparation with porous α-alumina tube

    International Nuclear Information System (INIS)

    Hwang, Gab-Jin; Onuki, Kaoru; Shimizu, Saburo

    1998-01-01

    It was investigated the preparation technique of hydrogen separation membrane to enhance the decomposition ratio of hydrogen iodide in the thermochemical IS process. Hydrogen separation membranes based on porous α-alumina tubes having pore size of 100 nm and 10 nm were prepared by chemical vapor deposition using tetraethylorthosilicate (TEOS) as the Si source. In the hydrogen separation membrane, its pore was closed by the deposited silica and then the permeation of gas was affected by the hindrance diffusion. At 600degC, the selectivity ratios (H 2 /N 2 ) were 5.2 and 160 for the membranes based on porous α-alumina tube having pore size of 100 nm and 10 nm, respectively. (author)

  19. Canadian Hydrogen Association workshop on building Canadian strength with hydrogen systems. Proceedings

    International Nuclear Information System (INIS)

    2006-01-01

    The Canadian Hydrogen Association workshop on 'Building Canadian Strength with Hydrogen Systems' was held in Montreal, Quebec, Canada on October 19-20, 2006. Over 100 delegates attended the workshop and there were over 50 presentations made. The Canadian Hydrogen Association (CHA) promotes the development of a hydrogen infrastructure and the commercialization of new, efficient and economic methods that accelerate the adoption of hydrogen technologies that will eventually replace fossil-based energy systems to reduce greenhouse gas emissions. This workshop focused on defining the strategic direction of research and development that will define the future of hydrogen related energy developments across Canada. It provided a forum to strengthen the research, development and innovation linkages among government, industry and academia to build Canadian strength with hydrogen systems. The presentations described new technologies and the companies that are making small scale hydrogen and hydrogen powered vehicles. Other topics of discussion included storage issues, hydrogen safety, competition in the hydrogen market, hydrogen fuel cell opportunities, nuclear-based hydrogen production, and environmental impacts

  20. Chemical composition effects of methylene containing polymers on gas emission under γ-irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ferry, M., E-mail: muriel.ferry@cea.fr [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Dannoux-Papin, A. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Dély, N. [CEA, DSM, IRAMIS, LIDYL, PCR, F-91191 Gif-sur-Yvette (France); Legand, S.; Durand, D.; Roujou, J.L.; Lamouroux, C.; Dauvois, V. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); Coignet, P.; Cochin, F. [AREVA NC DOR/RDP, 1 place Jean Millier, 92084 La Défense (France); Esnouf, S. [CEA, DEN, DPC, SECR, LRMO, F-91191 Gif-sur-Yvette (France); CEA, DSM, IRAMIS, LIDYL, PCR, F-91191 Gif-sur-Yvette (France)

    2014-09-01

    The presence of different chemical groups in methylene containing polymers can lead to very different behaviors under ionizing radiation. To better understand the effect of these groups on gas production under γ-irradiation, especially on hydrogen formation, and to study the efficiency of energy transfer between chemical groups, several methylene containing polymers with different controlled group concentrations were studied in inert atmosphere. We analyzed the influence of the nature and position of the chemical group using methylene containing copolymers with aliphatic side-chains (different lengths), ester groups in the side-chains (different concentrations) and ester groups in the polymer backbone (different concentrations). Radiation chemical yields of H{sub 2}, CO, CO{sub 2} and CH{sub 4} were determined at room temperature by high resolution mass spectrometry. On the basis of these results, we attempt to obtain a better understanding of the mechanisms involved. It can be observed that crystallinity and aliphatic side-chain have no effect on hydrogen formation. On contrary, esters on side-chain and in the backbone have an important influence on hydrogen formation, with the most important effect when esters groups are in the backbone. In these two kind of materials, energy fraction transferred from methylene to ester groups has been quantified and only 10 wt% (or less) of ester groups are sufficient to protect effectively the aliphatic moiety.

  1. Research Progress on the Indirect Hydrogenation of Carbon Dioxide to Methanol.

    Science.gov (United States)

    Du, Xian-Long; Jiang, Zheng; Su, Dang Sheng; Wang, Jian-Qiang

    2016-02-19

    Methanol is a sustainable source of liquid fuels and one of the most useful organic chemicals. To date, most of the work in this area has focused on the direct hydrogenation of CO2 to methanol. However, this process requires high operating temperatures (200-250 °C), which limits the theoretical yield of methanol. Thus, it is desirable to find a new strategy for the efficient conversion of CO2 to methanol at relatively low reaction temperatures. This Minireview seeks to outline the recent advances on the indirect hydrogenation of CO2 to methanol. Much emphasis is placed on discussing specific systems, including hydrogenation of CO2 derivatives (organic carbonates, carbamates, formates, cyclic carbonates, etc.) and cascade reactions, with the aim of critically highlighting both the achievements and remaining challenges associated with this field. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Why so few Women on Boards of Directors?

    DEFF Research Database (Denmark)

    Smith, Nina; Parrotta, Pierpaolo

    2015-01-01

    This paper analyzes the determinants of women’s representation on boards of directors based on a panel of all privately owned or listed Danish firms with at least 50 employees observed during the period 1998–2010. We focus on the directors who are not elected by the employees and test three...... nonemployee-elected female board members. We also find clear evidence of a tokenism behavior in Danish companies. The likelihood of enlarging the share of non-employee-elected female board members is significantly smaller if one, two, or more women have sat on the board of directors. Finally, the pipeline...... suggests that an important way to increase the female proportion of non-employee-elected board members is that more women reach top executive positions....

  3. Investigation of hydrogen generation in a three reactor chemical looping reforming process

    International Nuclear Information System (INIS)

    Khan, Mohammed N.; Shamim, Tariq

    2016-01-01

    Highlights: • Three-reactor based chemical looping reforming system for hydrogen production. • Investigation of operating parameters using a system-level model. • Optimum operating conditions for hydrogen production are identified. • Different operating parameters affect the reactor temperatures differently. - Abstract: Chemical looping reforming (CLR) is a relatively new method to produce hydrogen (H_2) and is also used as an energy conversion method for solid, liquid or gaseous fuels. There are various advantages of this method such as inherent carbon dioxide (CO_2) capture, minimal NOx emissions and the H_2 production. In this process, there is no direct contact between the fuel and oxidizer. This method utilizes oxygen from an oxygen carrier which may be a transition metal. The idea is to split the combustion process into three separate sub-processes by employing three separate reactors: air reactor where the oxygen carrier is oxidized by air, fuel reactor where natural gas is oxidized to produce a stream of CO_2 and H_2O and steam reactor where the steam is reduced to produce H_2. In this study, a thermodynamic model with iron oxides as oxygen carrier has been developed using Aspen Plus by employing conservation of mass and energy for all the components of the CLR system. The developed model was employed to investigate the effect of various operating parameters such as mass flow rates of air, fuel, steam and oxygen carrier and fraction of inert material on H_2 and CO_2 production and key reactor temperatures. The results show that the H_2 production increases with the increase in air, fuel and steam flow rates up to a certain limit and stays constant for higher flow rates. The CO_2 production follows a similar trend. Similarly, the H_2 production also increases with the increase in oxide flow rate and fraction of inert material up to a particular value, but then decrease for higher oxide flow rates and inert fractions. Reactor temperatures were also

  4. Dependence of hydrogen-induced lattice defects and hydrogen embrittlement of cold-drawn pearlitic steels on hydrogen trap state, temperature, strain rate and hydrogen content

    International Nuclear Information System (INIS)

    Doshida, Tomoki; Takai, Kenichi

    2014-01-01

    The effects of the hydrogen state, temperature, strain rate and hydrogen content on hydrogen embrittlement susceptibility and hydrogen-induced lattice defects were evaluated for cold-drawn pearlitic steel that absorbed hydrogen in two trapping states. Firstly, tensile tests were carried out under various conditions to evaluate hydrogen embrittlement susceptibility. The results showed that peak 2 hydrogen, desorbed at temperatures above 200 °C as determined by thermal desorption analysis (TDA), had no significant effect on hydrogen embrittlement susceptibility. In contrast, hydrogen embrittlement susceptibility increased in the presence of peak 1 hydrogen, desorbed from room temperature to 200 °C as determined by TDA, at temperatures higher than −30 °C, at lower strain rates and with higher hydrogen content. Next, the same effects on hydrogen-induced lattice defects were also evaluated by TDA using hydrogen as a probe. Peak 2 hydrogen showed no significant effect on either hydrogen-induced lattice defects or hydrogen embrittlement susceptibility. It was found that hydrogen-induced lattice defects formed under the conditions where hydrogen embrittlement susceptibility increased. This relationship indicates that hydrogen embrittlement susceptibility was higher under the conditions where the formation of hydrogen-induced lattice defects tended to be enhanced. Since hydrogen-induced lattice defects formed by the interaction between hydrogen and strain were annihilated by annealing at a temperature of 200 °C, they were presumably vacancies or vacancy clusters. One of the common atomic-level changes that occur in cold-drawn pearlitic steel showing higher hydrogen embrittlement susceptibility is the formation of vacancies and vacancy clusters

  5. Hydrogen Filling Station

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Robert F; Sabacky, Bruce; Anderson II, Everett B; Haberman, David; Al-Hassin, Mowafak; He, Xiaoming; Morriseau, Brian

    2010-02-24

    Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. The Freedom CAR and Freedom FUEL initiatives emphasize the importance of hydrogen as a future transportation fuel. Presently, Las Vegas has one hydrogen fueling station powered by natural gas. However, the use of traditional sources of energy to produce hydrogen does not maximize the benefit. The hydrogen fueling station developed under this grant used electrolysis units and solar energy to produce hydrogen fuel. Water and electricity are furnished to the unit and the output is hydrogen and oxygen. Three vehicles were converted to utilize the hydrogen produced at the station. The vehicles were all equipped with different types of technologies. The vehicles were used in the day-to-day operation of the Las Vegas Valley Water District and monitoring was performed on efficiency, reliability and maintenance requirements. The research and demonstration utilized for the reconfiguration of these vehicles could lead to new technologies in vehicle development that could make hydrogen-fueled vehicles more cost effective, economical, efficient and more widely used. In order to advance the development of a hydrogen future in Southern Nevada, project partners recognized a need to bring various entities involved in hydrogen development and deployment together as a means of sharing knowledge and eliminating duplication of efforts. A road-mapping session was held in Las Vegas in June 2006. The Nevada State Energy Office, representatives from DOE, DOE contractors and LANL, NETL, NREL were present. Leadership from the National hydrogen Association Board of Directors also attended. As a result of this session, a roadmap for hydrogen development was created. This roadmap has the ability to become a tool for use by other road-mapping efforts in the hydrogen community. It could also become a standard template for other states or even countries to approach planning for a hydrogen

  6. Optical and passivating properties of hydrogenated amorphous silicon nitride deposited by plasma enhanced chemical vapour deposition for application on silicon solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Wight, Daniel Nilsen

    2008-07-01

    Within this thesis, several important subjects related to the use of amorphous silicon nitride made by plasma enhanced chemical vapour deposition as an anti-reflective coating on silicon solar cells are presented. The first part of the thesis covers optical simulations to optimise single and double layer anti-reflective coatings with respect to optical performance when situated on a silicon solar cell. The second part investigates the relationship between important physical properties of silicon nitride films when deposited under different conditions. The optical simulations were either based on minimising the reflectance off a silicon nitride/silicon wafer stack or maximising the transmittance through the silicon nitride into the silicon wafer. The former method allowed consideration of the reflectance off the back surface of the wafer, which occurs typically at wavelengths above 1000 nm due to the transparency of silicon at these wavelengths. However, this method does not take into consideration the absorption occurring in the silicon nitride, which is negligible at low refractive indexes but quite significant when the refractive index increases above 2.1. For high-index silicon nitride films, the latter method is more accurate as it considers both reflectance and absorbance in the film to calculate the transmittance into the Si wafer. Both methods reach similar values for film thickness and refractive index for optimised single layer anti-reflective coatings, due to the negligible absorption occurring in these films. For double layer coatings, though, the reflectance based simulations overestimated the optimum refractive index for the bottom layer, which would have lead to excessive absorption if applied to real anti-reflective coatings. The experimental study on physical properties for silicon nitride films deposited under varying conditions concentrated on the estimation of properties important for its applications, such as optical properties, passivation

  7. Selective production of hydrogen peroxide and oxidation of hydrogen sulfide in an unbiased solar photoelectrochemical cell

    DEFF Research Database (Denmark)

    Zong, Xu; Chen, Hongjun; Seger, Brian

    2014-01-01

    A solar-to-chemical conversion process is demonstrated using a photoelectrochemical cell without external bias for selective oxidation of hydrogen sulfide (H2S) to produce hydrogen peroxide (H2O2) and sulfur (S). The process integrates two redox couples anthraquinone/anthrahydroquinone and I−/I3......−, and conceptually illustrates the remediation of a waste product for producing valuable chemicals....

  8. An Experimental and Chemical Kinetics Study of the Combustion of Syngas and High Hydrogen Content Fuels

    Energy Technology Data Exchange (ETDEWEB)

    Santoro, Robers [Pennsylvania State Univ., State College, PA (United States); Dryer, Frederick [Princeton Univ., NJ (United States); Ju, Yiguang [Princeton Univ., NJ (United States)

    2013-09-30

    An integrated and collaborative effort involving experiments and complementary chemical kinetic modeling investigated the effects of significant concentrations of water and CO2 and minor contaminant species (methane [CH4], ethane [C2H6], NOX, etc.) on the ignition and combustion of HHC fuels. The research effort specifically addressed broadening the experimental data base for ignition delay, burning rate, and oxidation kinetics at high pressures, and further refinement of chemical kinetic models so as to develop compositional specifications related to the above major and minor species. The foundation for the chemical kinetic modeling was the well validated mechanism for hydrogen and carbon monoxide developed over the last 25 years by Professor Frederick Dryer and his co-workers at Princeton University. This research furthered advance the understanding needed to develop practical guidelines for realistic composition limits and operating characteristics for HHC fuels. A suite of experiments was utilized that that involved a high-pressure laminar flow reactor, a pressure-release type high-pressure combustion chamber and a high-pressure turbulent flow reactor.

  9. Factors determining the activity of catalysts of various chemical types in the oxidation of hydrogen. I. Oxidation and isotope exchange of hydrogen on cobalt monoxide-oxide

    International Nuclear Information System (INIS)

    Polgikh, L.Y.; Golodets, G.I.; Il'chenko, N.I.

    1985-01-01

    On the basis of data on the kinetics of the reaction 2H 2 + O 2 = 2H 2 O isotope exchange H 2 + D 2 = 2HD under the conditions of oxidative catalysis, and the kinetic isotope effect, a mechanism is proposed for the oxidation of hydrogen on cobalt monoxide-oxide. At low temperatures the reaction proceeds according to a mechanism of alternating reduction-reoxidation of the surface with the participation of hydrogen adsorbed in molecular form; at increased temperature and low P 02 /P /SUB H2/ ratios, a significant contribution to the observed rate is made by a mechanism including dissociative chemisorption of hydrogen

  10. Method and system for hydrogen evolution and storage

    Science.gov (United States)

    Thorn, David L.; Tumas, William; Hay, P. Jeffrey; Schwarz, Daniel E.; Cameron, Thomas M.

    2012-12-11

    A method and system for storing and evolving hydrogen (H.sub.2) employ chemical compounds that can be hydrogenated to store hydrogen and dehydrogenated to evolve hydrogen. A catalyst lowers the energy required for storing and evolving hydrogen. The method and system can provide hydrogen for devices that consume hydrogen as fuel.

  11. Report on achievements in research and development in Sunshine Project - Hydrogen energy. Studies on prevention of hydrogen explosion disasters (Fiscal 1974 through fiscal 1983); 1974 - 1983 nendo suiso no bakuhatsu saigai boshi no kenkyu seika hokokusho. Suiso energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1984-03-01

    Experimental studies have been performed on prevention of hydrogen explosion disasters in attempting practical use of hydrogen energy. Regarding the prevention of disasters caused by high-pressure hydrogen, elucidation was made on causes of the fire, and estimation expression was introduced on size of fire caused by ignition. Measurements were also made on explosion limit and explosion pressure of low-temperature hydrogen gas. Furthermore, a flame arrester for hydrogen was developed. In studies on prevention of explosion of liquefied hydrogen, investigations were given on physical and chemical natures of a system mixed with air and oxygen, and on explosion causing sensitivity against impact to have elucidate danger of impurities in liquefied hydrogen. An experiment verified the effectiveness of carbon dioxide or powder extinguishing agent in the case of liquefied hydrogen fire. With regard to metal hydrides, elucidation was given on their ignitability in atmosphere and danger of dust explosion. In addition, it was made clear that containers may break down due to rise in internal pressure as a result of temperature rise, whereas safety valves were discussed, and models were decided. (NEDO)

  12. Storage, generation, and use of hydrogen

    Science.gov (United States)

    McClaine, Andrew W.; Rolfe, Jonathan L.; Larsen, Christopher A.; Konduri, Ravi K.

    2006-05-30

    A composition comprising a carrier liquid; a dispersant; and a chemical hydride. The composition can be used in a hydrogen generator to generate hydrogen for use, e.g., as a fuel. A regenerator recovers elemental metal from byproducts of the hydrogen generation process.

  13. EVALUATION OF CEMENT-BONDED PARTICLE BOARD PRODUCED FROM AFZELIA AFRICANA WOOD RESIDUES

    Directory of Open Access Journals (Sweden)

    OLUFEMI A. SOTANNDE

    2012-12-01

    Full Text Available The study was design to evaluate the physical and mechanical properties of cement-bonded particleboards produced from Afzelia africana wood residues. The production variables investigated were three wood particle types (flakes, flake-sawdust mix and sawdust, three chemical accelerators (CaCl2, MgCl2 and AlCl3 and four wood-cement ratios (1:2.0, 1:2.5, 1:3.0 and 1:3.5. The accelerators were based on 2% by weight of cement used. The boards produced were subjected to physical tests such as density, percentage water absorption and thickness swelling. Mechanical properties evaluated were modulus of rupture, internal bonding strength and compressive strength. The results revealed that the type of particle used, wood-cement ratio and chemical additives had a marked influence on the physical and mechanical properties of the boards (p < 0.05. From quality view point, flake-sawdust composite ranked best while flake boards ranked least. Similarly, CaCl2 had the best influence on the setting of the boards followed by MgCl2 and AlCl3. Finally, it has been shown that particle boards that satisfied the BISON type HZ requirement and ISO 8335 can be produced from Afzelia africana particularly at wood-cement of 1:2.5 and above.

  14. Enhanced hydrogen storage in sandwich-structured rGO/Co1-xS/rGO hybrid papers through hydrogen spillover

    Science.gov (United States)

    Han, Lu; Qin, Wei; Jian, Jiahuang; Liu, Jiawei; Wu, Xiaohong; Gao, Peng; Hultman, Benjamin; Wu, Gang

    2017-08-01

    Reduced graphene oxide (rGO) based two-dimensional (2D) structures have been fabricated for electrochemical hydrogen storage. However, the effective transfer of atomic hydrogen to adjacent rGO surfaces is suppressed by binders, which are widely used in conventional electrochemical hydrogen storage electrodes, leading to a confining of the performance of rGO for hydrogen storage. As a proof of concept experiment, a novel strategy is developed to fabricate the binder-free sandwich-structured rGO/Co1-xS/rGO hybrid paper via facile ball milling and filtration process. Based on the structure investigation, Co1-xS is immobilized in the space between the individual rGO sheets by the creation of chemical "bridges" (Csbnd S bonds). Through the Csbnd S bonds, the atomic hydrogen is transferred from Co1-xS to rGO accompanying a Csbnd H chemical bond formation. When used as an electrode, the hybrid paper exhibits an improved hydrogen storage capacity of 3.82 wt% and, most importantly, significant cycling stability for up to 50 cycles. Excluding the direct hydrogen storage contribution from the Co1-xS in the hybrid paper, the hydrogen storage ability of rGO is enhanced by 10× through the spillover effects caused by the Co1-xS modifier.

  15. Chemical interesterification of soybean oil and fully hydrogenated soybean oil: Influence of the reaction time

    International Nuclear Information System (INIS)

    Ribeiro, Ana Paula Badan; Masuchi, Monise Helen; Grimaldi, Renato; Goncalves, Lireny Aparecida Guaraldo

    2009-01-01

    Chemical interesterification is an important alternative to produce zero trans fats. In practice, however, excessive reaction times are used to ensure complete randomization. This work evaluated the influence of the reaction time on the interesterification of soybean oil/fully hydrogenated soybean oil blend, carried out in the following conditions: 100 deg C, 500 rpm stirring speed, 0.4% (w/w) sodium methoxide catalyst. The triacylglycerol composition, solid fat content and melting point analysis showed that the reaction was very fast, reaching the equilibrium within 5 min. This result suggests the interesterification can be performed in substantially lower times, with reduction in process costs. (author)

  16. Solar Hydrogen Reaching Maturity

    Directory of Open Access Journals (Sweden)

    Rongé Jan

    2015-09-01

    Full Text Available Increasingly vast research efforts are devoted to the development of materials and processes for solar hydrogen production by light-driven dissociation of water into oxygen and hydrogen. Storage of solar energy in chemical bonds resolves the issues associated with the intermittent nature of sunlight, by decoupling energy generation and consumption. This paper investigates recent advances and prospects in solar hydrogen processes that are reaching market readiness. Future energy scenarios involving solar hydrogen are proposed and a case is made for systems producing hydrogen from water vapor present in air, supported by advanced modeling.

  17. Safety considerations for continuous hydrogen production test apparatus with capacity of 50 N-litter hydrogen per hour

    International Nuclear Information System (INIS)

    Onuki, Kaoru; Akino, Norio; Shimizu, Saburo; Nakajima, Hayato; Higashi, Shunichi; Kubo, Shinji

    2001-03-01

    Since the thermochemical hydrogen production Iodine-Sulfur process decomposes water into hydrogen and oxygen using toxic chemicals such as sulfuric acid, iodine and hydriodic acid, safety considerations are very important in its research and development. Therefore, before construction of continuous hydrogen production test apparatus with capacity of 50 N-litter hydrogen per hour, comprehensive safety considerations were carried out to examine the design and construction works of the test apparatus, and the experimental plans using the apparatus. Emphasis was given on the safety considerations on prevention of breakage of glasswares and presumable abnormalities, accidents and their countermeasures. This report summarizes the results of the considerations. (author)

  18. PWG4 perspective on ex-vessel hydrogen sources

    International Nuclear Information System (INIS)

    2000-07-01

    The purpose of this perspective document is to identify the potential ex-vessel hydrogen sources and to address the question whether, considered the uncertainties associated to these sources, further investigations are required. The statement is established with reference to the needs for safety evaluation of nuclear reactors under severe accident conditions. It is recognised that the views could be different if one looks at these issues from another standpoint. Since the TMI-2 accident in 1979, there had been a large interest in the nuclear reactor safety community for studying the behaviour of hydrogen in case of a severe accident. As a result, different 'state of the art' reports were produced. Examples of these documents are NUREG/CR-1561 and EUR 14307. In particular, they identified potential hydrogen sources during accidents, including ex-vessel sources. Various ex-vessel hydrogen sources, covering a variety of physical and chemical processes, were identified. Although their precise quantification and relative importance is to be established on a case by case basis with respect to the specific reactor design of interest, general trends can be formulated. The sources to be considered are the followings: - radiolysis of water; - corrosion reactions, - reaction of urania with steam and water; - core-concrete interaction; - debris-atmosphere interaction. These sources are discussed successively. The PWG4 (CSNI's Principal Working Group on the Confinement of Accidental Radioactive Releases) perspective on Ex-vessel Hydrogen Sources can be summarised in the following statements: 1. The issue of hydrogen sources must be considered as a whole and cannot be separated into in-vessel and ex-vessel issues. For significant sources that may not be accommodated by mitigation means associated to DBA, the uncertainty is largely dominated by the unknown extent of Zr oxidation during the in-vessel phase. 2. PWG4 notes that hydrogen production during corium quenching by water is

  19. Effect of hydrogen on hydrogen-methane turbulent non-premixed flame under MILD condition

    Energy Technology Data Exchange (ETDEWEB)

    Mardani, Amir; Tabejamaat, Sadegh [Department of Aerospace engineering, Amirkabir university of technology (Tehran polytechnic), Hafez Ave., PO. Box: 15875-4413, Tehran (Iran)

    2010-10-15

    Energy crises and the preservation of the global environment are placed man in a dilemma. To deal with these problems, finding new sources of fuel and developing efficient and environmentally friendly energy utilization technologies are essential. Hydrogen containing fuels and combustion under condition of the moderate or intense low-oxygen dilution (MILD) are good choices to replace the traditional ones. In this numerical study, the turbulent non-premixed CH{sub 4}+H{sub 2} jet flame issuing into a hot and diluted co-flow air is considered to emulate the combustion of hydrogen containing fuels under MILD conditions. This flame is related to the experimental condition of Dally et al. [Proc. Combust. Inst. 29 (2002) 1147-1154]. In general, the modelling is carried out using the EDC model, to describe turbulence-chemistry interaction, and the DRM-22 reduced mechanism and the GRI2.11 full mechanism to represent the chemical reactions of H{sub 2}/methane jet flame. The effect of hydrogen content of fuel on flame structure for two co-flow oxygen levels is studied by considering three fuel mixtures, 5%H{sub 2}+95%CH{sub 4}, 10%H{sub 2}+90%CH{sub 4} and 20% H{sub 2}+80%CH{sub 4}(by mass). In this study, distribution of species concentrations, mixture fraction, strain rate, flame entrainment, turbulent kinetic energy decay and temperature are investigated. Results show that the hydrogen addition to methane leads to improve mixing, increase in turbulent kinetic energy decay along the flame axis, increase in flame entrainment, higher reaction intensities and increase in mixture ignitability and rate of heat release. (author)

  20. Basic study on high temperature gas cooled reactor technology for hydrogen production

    International Nuclear Information System (INIS)

    Chang, Jong Hwa; Lee, W. J.; Lee, H. M.

    2003-01-01

    The annual production of hydrogen in the world is about 500 billion m 3 . Currently hydrogen is consumed mainly in chemical industries. However hydrogen has huge potential to be consumed in transportation sector in coming decades. Assuming that 10% of fossil energy in transportation sector is substituted by hydrogen in 2020, the hydrogen in the sector will exceed current hydrogen consumption by more than 2.5 times. Currently hydrogen is mainly produced by steam reforming of natural gas. Steam reforming process is chiefest way to produce hydrogen for mass production. In the future, hydrogen has to be produced in a way to minimize CO2 emission during its production process as well as to satisfy economic competition. One of the alternatives to produce hydrogen under such criteria is using heat source of high-temperature gas-cooled reactor. The high-temperature gas-cooled reactor represents one type of the next generation of nuclear reactors for safe and reliable operation as well as for efficient and economic generation of energy

  1. Preparation and characterization of enamel coating on pure titanium as a hydrogen penetration barrier

    Energy Technology Data Exchange (ETDEWEB)

    Tao, Jie, E-mail: taojie@nuaa.edu.cn [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016 (China); Guo, Xunzhong [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016 (China); Huang, Zhendong [Graduate School of Human and Environmental Studies, Kyoto University, oshida-Nihonmatsu-Cho, Sakyo-Ku, Kyoto shi 606-8501 (Japan); Liu, Hongbing [Shanghai Aircraft Manufacturing Co,. Ltd, Shanghai 200436 (China); Wang, Tao [College of Material Science and Technology, Nanjing University of Aeronautics and Astronautics, Nanjing, Jiangsu 210016 (China)

    2013-06-15

    Highlights: ► The enamel coating was prepared by spin-coating and enameling method. ► The dense enamel coatings were chemically bonded with TA1 substrate. ► The coatings possessed better thermal shock resistance property. ► The coatings had excellent ball-dropping impact properties. ► The enamel coating exhibited a good barrier effect to hydrogen isotope penetration. -- Abstract: The enamel coating with a thickness of 90–110 × 10{sup −6} m was prepared on TA1 substrate by spin-coating and enameling to solve the problems of hydrogen isotope penetration for commercial pure titanium TA1. The microstructure and the interfacial morphology of the samples were characterized respectively by X-ray diffraction, optical and scanning electron microscopy. The profiles of main elements at the interface were analyzed by EDS line-scanning. The experimental results indicated that the dense enamel coatings were chemically bonded with TA1 substrate, and possessed better thermal shock resistance and ball-dropping impact properties. It was concluded from the results of hydrogen charging test with Vickers microhardness measurement and deuterium penetration experiments that the as-prepared dense enamel coating exhibited a good barrier effect to hydrogen isotope penetration.

  2. Hydrogen-based industry from remote excess hydroelectricity

    International Nuclear Information System (INIS)

    Ouellette, N.; Rogner, H.-H.; Scott, D.S.

    1997-01-01

    This paper examines synergies, opportunities and barriers associated with hydrogen and excess hydro-electricity in remote areas. The work is based on a case study that examined the techno-economic feasibility of a new hydrogen-based industry using surplus/off-peak generating capacity of the Taltson Dam and Generating Station in the Northwest Territories, Canada. After evaluating the amount and cost of hydrogen that could be produced from the excess capacity, the study investigates three hydrogen utilization scenarios: (1) merchant liquid or compressed hydrogen, (2) hydrogen as a chemical feedstock for the production of hydrogen peroxide, (3) methanol production from biomass, oxygen and hydrogen. Hydrogen peroxide production is the most promising and attractive strategy in the Fort Smith context. The study also illustrates patterns that recur in isolated sites throughout the world. (Author)

  3. Hydrogen production by Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Chaudhuri Surabhi

    2005-12-01

    Full Text Available Abstract The limited fossil fuel prompts the prospecting of various unconventional energy sources to take over the traditional fossil fuel energy source. In this respect the use of hydrogen gas is an attractive alternate source. Attributed by its numerous advantages including those of environmentally clean, efficiency and renew ability, hydrogen gas is considered to be one of the most desired alternate. Cyanobacteria are highly promising microorganism for hydrogen production. In comparison to the traditional ways of hydrogen production (chemical, photoelectrical, Cyanobacterial hydrogen production is commercially viable. This review highlights the basic biology of cynobacterial hydrogen production, strains involved, large-scale hydrogen production and its future prospects. While integrating the existing knowledge and technology, much future improvement and progress is to be done before hydrogen is accepted as a commercial primary energy source.

  4. Decentralized and direct solar hydrogen production: Towards a hydrogen economy in MENA region

    Energy Technology Data Exchange (ETDEWEB)

    Bensebaa, Farid; Khalfallah, Mohamed; Ouchene, Majid

    2010-09-15

    Hydrogen has certainly some advantages in spite of its high cost and low efficiency when compared to other energy vectors. Solar energy is an abundant, clean and renewable source of energy, currently competing with fossil fuel for water heating without subsidy. Photo-electrochemical, thermo-chemicals and photo-biological processes for hydrogen production processes have been demonstrated. These decentralised hydrogen production processes using directly solar energy do not require expensive hydrogen infrastructure for packaging and delivery in the short and medium terms. MENA region could certainly be considered a key area for a new start to a global deployment of hydrogen economy.

  5. (LiNH2-MgH2): a viable hydrogen storage system

    International Nuclear Information System (INIS)

    Luo Weifang

    2004-01-01

    One of the problems related to the employment of hydrogen-based fuel cells for vehicular transportation is 'on board' storage. Hydrogen storage in solids has long been recognized as one of the most practical approaches for this purpose. The capacity of existing storage materials is markedly below that needed for vehicular use. Recently Chen et al. [Nature 420 (21) (2002) 302; J. Phys. Chem. B 107 (2003) 10967] reported a lithium nitride/imide system, with a high capacity, 11.5 wt.%, however, its operating temperature and pressure are not satisfactory for vehicular application. In this research a new storage material has been developed, which is from the partial substitution of lithium by magnesium in the nitride/imide system. The plateau pressure of this new Mg-substituted system is about 30 bar and 200 deg. C with a H capacity of 4.5 wt.% and possibly higher. This is a very promising H-storage material for 'on board' storage for vehicular applications

  6. High Density Hydrogen Storage in Metal Hydride Composites with Air Cooling

    OpenAIRE

    Dieterich, Mila; Bürger, Inga; Linder, Marc

    2015-01-01

    INTRODUCTION In order to combine fluctuating renewable energy sources with the actual demand of electrical energy, storages are essential. The surplus energy can be stored as hydrogen to be used either for mobile use, chemical synthesis or reconversion when needed. One possibility to store the hydrogen gas at high volumetric densities, moderate temperatures and low pressures is based on a chemical reaction with metal hydrides. Such storages must be able to absorb and desorb the hydrogen qu...

  7. Fiscal 1975 Sunshine Project research report. General research on hydrogen energy subsystems and their peripheral technologies (General research on hydrogen energy subsystems); 1975 nendo suiso riyo subsystem no sogoteki kento to shuhen gijutsu ni kansuru kenkyu seika hokokusho. Suiso riyo subsystem no sogoteki kento

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1976-03-01

    This report is composed of the part 1 'General research on hydrogen energy subsystems' and the part 2 'Outline of researches on every use pattern of hydrogen'. The part 1 outlines the fiscal 1975 activity and result, the latest research situation, the latest domestic and overseas R and D situations, some extracted problems, and the future research issues. The part 2 summarizes the research results of every committee with the following themes: (1) Hydrogen combustion technology (combustion characteristics and technology of hydrogen-methane mixture, home and industrial combustors, study on hydrogen energy system), (2) Fuel cell, (3) Automobile engine (merits and demerits of automobile hydrogen engine, problems and their possible solutions on hydrogen engine, urgent research issues), (4) Aircraft engine (prospect for hydrogen use in air transport in Japan, study on various systems around airports in hydrogen use, technical study on aircraft using hydrogen fuel), (5) Gas turbine, and (6) Chemical use of hydrogen. (NEDO)

  8. Influence of addition of hydrogen produced on board in the performance of a stationary diesel engine

    International Nuclear Information System (INIS)

    Rodríguez Matienzo, Jorge M.; Domínguez Valdés, Alejandro

    2017-01-01

    A commercial electrolytic cell is assessed for supplying HHO produced on board as additional fuel for a stationary diesel IC engine. The cell uses KOH as electrolytic and is fed by the own battery of the engine. First, different concentrations of KOH used as electrolytic were tested in order to obtain the adequate value for the performance of the cell regarding its temperature and HHO production. The cell plates were connected in different combinations looking for a good productivity. The engine was tested in several load regimes, measuring fuel consumption and others parameters. Results show variable fuel savings, depending on engine load and speed. (author)

  9. Chemical Soups Around Cool Stars

    Science.gov (United States)

    2009-01-01

    This artist's conception shows a young, hypothetical planet around a cool star. A soupy mix of potentially life-forming chemicals can be seen pooling around the base of the jagged rocks. Observations from NASA's Spitzer Space Telescope hint that planets around cool stars the so-called M-dwarfs and brown dwarfs that are widespread throughout our galaxy might possess a different mix of life-forming, or prebiotic, chemicals than our young Earth. Life on our planet is thought to have arisen out of a pond-scum-like mix of chemicals. Some of these chemicals are thought to have come from a planet-forming disk of gas and dust that swirled around our young sun. Meteorites carrying the chemicals might have crash-landed on Earth. Astronomers don't know if these same life-generating processes are taking place around stars that are cooler than our sun, but the Spitzer observations show their disk chemistry is different. Spitzer detected a prebiotic molecule, called hydrogen cyanide, in the disks around yellow stars like our sun, but found none around cooler, less massive, reddish stars. Hydrogen cyanide is a carbon-containing, or organic compound. Five hydrogen cyanide molecules can join up to make adenine a chemical element of the DNA molecule found in all living organisms on Earth.

  10. Nuclear hydrogen production: re-examining the fusion option

    International Nuclear Information System (INIS)

    Baindur, S.

    2007-01-01

    This paper describes a scheme for nuclear hydrogen production by fusion. The basic idea is to use nuclear energy of the fuel (hydrogen plasma) to produce molecular hydrogen fro carbon-free hydrogen compounds. The hydrogen is then stored and utilized electrochemically in fuel cells or chemically as molecular hydrogen in internal combustion engines

  11. Effect of hydrogen environment on the separation of Fe grain boundaries

    International Nuclear Information System (INIS)

    Wang, Shuai; Martin, May L.; Robertson, Ian M.; Sofronis, Petros

    2016-01-01

    A density-functional theory based empirical potential was used to explore the energies of different types of Fe grain boundaries and free surfaces in thermodynamic equilibrium with a hydrogen environment. The classical model for calculating the ideal work of separation with solute atoms is extended to account for every trapping site. This yields the lowest-energy structures at different hydrogen chemical potentials (or gas pressures). At hydrogen gas pressures lower than 1000 atm, the reduction of the reversible work of separation is less than 33% and it increases to 36% at a gas pressure of 5000 atm. Near the hydride formation limit, 5 × 10 4  atm, the reduction is 44%. Based on the magnitude of these reductions for complete decohesion, and accounting for experimental observations of the microstructure associated with hydrogen-induced intergranular fracture of Fe, it is posited that hydrogen-enhanced plasticity and attendant effects establish the local conditions responsible for the transition in fracture mode from transgranular to intergranular. The conclusion is reached that intergranular failure occurs by a reduction of the cohesive energy but with contributions from structural as well as compositional changes in the grain boundary that are driven by hydrogen-enhanced plasticity processes.

  12. Hydrogen energy based on nuclear energy

    International Nuclear Information System (INIS)

    2002-06-01

    A concept to produce hydrogen of an energy carrier using nuclear energy was proposed since 1970s, and a number of process based on thermochemical method has been investigated after petroleum shock. As this method is used high temperature based on nuclear reactors, these researches are mainly carried out as a part of application of high temperature reactors, which has been carried out at an aim of the high temperature reactor application in the Japan Atomic Energy Research Institute. On October, 2000, the 'First International Conference for Information Exchange on Hydrogen Production based on Nuclear Energy' was held by auspice of OECD/NEA, where hydrogen energy at energy view in the 21st Century, technology on hydrogen production using nuclear energy, and so on, were published. This commentary was summarized surveys and researches on hydrogen production using nuclear energy carried out by the Nuclear Hydrogen Research Group established on January, 2001 for one year. They contains, views on energy and hydrogen/nuclear energy, hydrogen production using nuclear energy and already finished researches, methods of hydrogen production using nuclear energy and their present conditions, concepts on production plants of nuclear hydrogen, resources on nuclear hydrogen production and effect on global environment, requests from market and acceptability of society, and its future process. (G.K.)

  13. Radiation chemical yields for formation of molecular hydrogen in alcohols based on the cyclohexane ring

    International Nuclear Information System (INIS)

    Val'ter, A.I.; Kovalev, G.V.

    1989-01-01

    Within the framework of the general problem of studying the radiolysis mechanism for alcohols based on the cyclohexane ring, we have determined the yields of molecular hydrogen in γ-irradiated cyclohexanol, 1,2-cis- and 1,2-trans-cyclohexanediols, and inositol (cyclohexanehexol). The cyclohexanol and also powders of the polyols were placed into ampuls, deaerated in a vacuum apparatus and irradiated with 60 Co γ-rays at 77 K and 293 K. After irradiation, the samples were heated up to 373 K (the polyol crystals were heated until melting) and the hydrogen evolved from the liquid phase was determined by gas chromatography

  14. FY 1974 report on the results of the Sunshine Project. Comprehensive study of hydrogen use subsystem and study on the periphery technology (Study on the chemical utilization); 1974 nendo suiso riyo subsystem no sogoteki kento to shuhen gijutsu ni kansuru kenkyu seika hokokusho. Kagaku riyo ni kansuru kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-07-01

    This paper reports on the present situation of the chemical use of hydrogen and oxygen, and the short-term, medium-term, and long-term forecast. The main usage of hydrogen is ammonia synthesis, petroleum refining, and methanol synthesis. In the usage of these three, there are factors of structural changes now and in future, and it is extremely difficult to predict the amount in a short term up to around 1980. In a medium term prediction, from the result of predicting the demand of ammonia, methanol and hydrodesulfurization, the total 1985 hydrogen demand is estimated at approximately 60 billion Nm{sup 3}, and approximately 67 billion Nm{sup 3} as the gross hydrogen demand. Further, judging from that synthetic protein, fuel use methanol, and reduced iron are estimated to reach a certain production size in and after 1985, new demand for hydrogen is expected to be approximately 100 billion Nm{sup 3} mostly including fuel use methanol. In a long term prediction, it is extremely hard to predict the demand because of various factors existing in Japan and abroad. As predicted in a medium term, the amount of chemical use of hydrogen is expected to increase more and more, even if calculating it only in the field of ammonia synthesis, petroleum refining, and methanol synthesis. (NEDO)

  15. Influence of chemical agents on the surface area and porosity of active carbon hollow fibers

    Directory of Open Access Journals (Sweden)

    LJILJANA M. KLJAJEVIĆ

    2011-09-01

    Full Text Available Active carbon hollow fibers were prepared from regenerated polysulfone hollow fibers by chemical activation using: disodium hydrogen phosphate 2-hydrate, disodium tetraborate 10-hydrate, hydrogen peroxide, and diammonium hydrogen phosphate. After chemical activation fibers were carbonized in an inert atmosphere. The specific surface area and porosity of obtained carbons were studied by nitrogen adsorption–desorption isotherms at 77 K, while the structures were examined with scanning electron microscopy and X-ray diffraction. The activation process increases these adsorption properties of fibers being more pronounced for active carbon fibers obtained with disodium tetraborate 10-hydrate and hydrogen peroxide as activator. The obtained active hollow carbons are microporous with different pore size distribution. Chemical activation with phosphates produces active carbon material with small surface area but with both mesopores and micropores. X-ray diffraction shows that besides turbostratic structure typical for carbon materials, there are some peaks which indicate some intermediate reaction products when sodium salts were used as activating agent. Based on data from the electrochemical measurements the activity and porosity of the active fibers depend strongly on the oxidizing agent applied.

  16. Boron-doped hydrogenated Al{sub 3} clusters: A material for hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Muz, İskender, E-mail: iskender.muz@nevsehir.edu.tr [Faculty of Education, Department of Science Education, Nevsehir Haci Bektas Veli University, 50300, Nevsehir (Turkey); Atiş, Murat [Kayseri Vocational School, Electricity and Energy Department, Erciyes University, 38300, Kayseri (Turkey)

    2016-05-15

    The energetic and structural stabilities of Al{sub 3}BH{sub 2n} (n = 0–6) clusters are investigated using ab initio calculations. Structural isomers are found using the stochastic search method to search for minima structures, followed by B3LYP optimizations; single-point CCSD(T) calculations are performed to compute relative energies. Chemical bonding analysis is also performed using the adaptive natural density partitioning method to investigate the chemical bonding in the clusters and to elucidate their structural evolution. Our results and analyses indicate that the stability of the boron-doped hydrogenated Al{sub 3} clusters increases as more hydrogen molecules are adsorbed, whereas the H{sub 2} loss energy decreases. The results are in good agreement with available theoretical findings. - Highlights: • The boron-doped hydrogenated Al{sub 3} clusters are generated using stochastic search method. • The energetic and structural stabilities are investigated in detail. • The chemical bonding analysis is performed by using AdNDP analysis. • The doping by boron allows development of better aluminum-based metal hydrides.

  17. Recent Progress and New Perspectives on Metal Amide and Imide Systems for Solid-State Hydrogen Storage

    Directory of Open Access Journals (Sweden)

    Sebastiano Garroni

    2018-04-01

    Full Text Available Hydrogen storage in the solid state represents one of the most attractive and challenging ways to supply hydrogen to a proton exchange membrane (PEM fuel cell. Although in the last 15 years a large variety of material systems have been identified as possible candidates for storing hydrogen, further efforts have to be made in the development of systems which meet the strict targets of the Fuel Cells and Hydrogen Joint Undertaking (FCH JU and U.S. Department of Energy (DOE. Recent projections indicate that a system possessing: (i an ideal enthalpy in the range of 20–50 kJ/mol H2, to use the heat produced by PEM fuel cell for providing the energy necessary for desorption; (ii a gravimetric hydrogen density of 5 wt. % H2 and (iii fast sorption kinetics below 110 °C is strongly recommended. Among the known hydrogen storage materials, amide and imide-based mixtures represent the most promising class of compounds for on-board applications; however, some barriers still have to be overcome before considering this class of material mature for real applications. In this review, the most relevant progresses made in the recent years as well as the kinetic and thermodynamic properties, experimentally measured for the most promising systems, are reported and properly discussed.

  18. Photo- and radiation-chemical stability of molecules. Reactions of monomolecular hydrogen atom splitting off

    International Nuclear Information System (INIS)

    Plotnikov, V.G.; Ovchinnikov, A.A.

    1978-01-01

    In the review of works published up to 1978 one of the main problems of radiation chemistry is discussed, namely the relationship between the structure of organic molecules and their resistance to the effect of ionizing radiation. Theoretical aspects of this problem are considered for reactions of monomolecular hydrogen atom splitting off. It is shown that the radical yield in low-temperature radiation-chemical experiments is connected with the position of lower triplet states of molecules, ionization potentials, polarity of medium and the energy of C-H bonds in cation radicals

  19. Summarized achievement report on the Sunshine Project in fiscal 1980 (Hydrogen energy); 1980 nendo seika hokokusho gaiyoshu. Suiso energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-04-01

    This paper summarizes the achievement report on the Sunshine Project in fiscal 1980 for hydrogen energy research. In hydrogen manufacturing using the electrolytic process, improvements were made on membranes and electrodes. Solid electrolyte electrolysis is also under research. Researches are continued on reaction, separating operation, and device materials for the iodine system cycle in the thermo-chemical method. In the iron system cycle, a reaction experimenting equipment was fabricated on the trial basis, and tests and evaluation were performed on the material and heat balances. In the mixed system cycle, researches on the light irradiation electrolytic process were continued, whereas the light collecting rate was raised by using a lens to increase light intensity, having enhanced successfully the reaction rate to 60 to 80%. A heat diffusion column for HI decomposition and separation (hydrogen acquisition) was discussed in terms of chemical engineering. Development works are continued on metal hydrides for hydrogen transportation, and durability tests are also being performed. Same applies to hydrogen storage. A model burner was fabricated on the trial basis, and catalytic combustion was studied as development of a combustion technology that matches the requirements for safe hydrogen combustion and suppression of NOx emission. Searches were continued on catalysts and solid electrolyte materials for fuel cells. Thin film sold electrolyte fuel cells constructed by using the evaporation process are also being studied. The paper also describes measures for hydrogen safety assurance and researches on energy systems. (NEDO)

  20. Fuel cell cars in a microgrid for synergies between hydrogen and electricity networks

    International Nuclear Information System (INIS)

    Alavi, Farid; Park Lee, Esther; Wouw, Nathan van de; De Schutter, Bart; Lukszo, Zofia

    2017-01-01

    Highlights: • A novel concept of a flexible energy system that uses fuel cell cars as dispatchable power plants. • Synergies between hydrogen and electricity networks by operating of fuel cell cars in a microgrid. • A robust min-max model predictive control scheme for optimal dispatch of the fuel cell cars. • A novel model predictive control scheme to govern the system operation. - Abstract: Fuel cell electric vehicles convert chemical energy of hydrogen into electricity to power their motor. Since cars are used for transport only during a small part of the time, energy stored in the on-board hydrogen tanks of fuel cell vehicles can be used to provide power when cars are parked. In this paper, we present a community microgrid with photovoltaic systems, wind turbines, and fuel cell electric vehicles that are used to provide vehicle-to-grid power when renewable power generation is scarce. Excess renewable power generation is used to produce hydrogen, which is stored in a refilling station. A central control system is designed to operate the system in such a way that the operational costs are minimized. To this end, a hybrid model for the system is derived, in which both the characteristics of the fuel cell vehicles and their traveling schedules are considered. The operational costs of the system are formulated considering the presence of uncertainty in the prediction of the load and renewable energy generation. A robust min-max model predictive control scheme is developed and finally, a case study illustrates the performance of the designed system.

  1. Wireless Hydrogen Smart Sensor Based on Pt/Graphene-Immobilized Radio-Frequency Identification Tag.

    Science.gov (United States)

    Lee, Jun Seop; Oh, Jungkyun; Jun, Jaemoon; Jang, Jyongsik

    2015-08-25

    Hydrogen, a clean-burning fuel, is of key importance to various industrial applications, including fuel cells and the aerospace and automotive industries. However, hydrogen gas is odorless, colorless, and highly flammable; thus, appropriate safety protocol implementation and monitoring are essential. Highly sensitive hydrogen-gas leak detection and surveillance systems are needed; additionally, the ability to monitor large areas (e.g., cities) via wireless networks is becoming increasingly important. In this report, we introduce a radio frequency identification (RFID)-based wireless smart-sensor system, composed of a Pt-decorated reduced graphene oxide (Pt_rGO)-immobilized RFID sensor tag and an RFID-reader antenna-connected network analyzer to detect hydrogen gas. The Pt_rGOs, produced using a simple chemical reduction process, were immobilized on an antenna pattern in the sensor tag through spin coating. The resulting Pt_rGO-based RFID sensor tag exhibited a high sensitivity to hydrogen gas at unprecedentedly low concentrations (1 ppm), with wireless communication between the sensor tag and RFID-reader antenna. The wireless sensor tag demonstrated flexibility and a long lifetime due to the strong immobilization of Pt_rGOs on the substrate and battery-independent operation during hydrogen sensing, respectively.

  2. Ten questions on hydrogen Jean Dhers

    International Nuclear Information System (INIS)

    2005-01-01

    The author proposes explanations and comments on the use of hydrogen in energy production. He discusses whether hydrogen can be a new energy technology within the context of a sustainable development, whether hydrogen is actually an energy vector, what would be the benefits of using hydrogen in energy applications, why it took so much time to be interested in hydrogen, when the hydrogen vector will be needed, whether we can economically produce hydrogen to meet energy needs (particularly in transports), whether hydrogen is the best suited energy vector for ground transports in the future, how to retail hydrogen for ground transports, what are the difficulties to store hydrogen for ground transport applications, and how research programs on hydrogen are linked together

  3. Magnetic field effects on the chemical equilibrium in LaCo5-H system

    International Nuclear Information System (INIS)

    Yamamoto, Isao; Yamaguchi, Masuhiro; Deguchi, Noritaka; Miura, Shigeto.

    1997-01-01

    Magnetic field effects on the chemical equilibrium were investigated for a ferromagnetic metal hydride-hydrogen system. The equilibrium hydrogen pressure, measured in the β+γ region for LaCo 5 H x , changed significantly with the applied magnetic fields up to 15 T in the temperature range between 293 and 343 K. Namely, the measured hydrogen pressure increased with increasing magnetic fields. However, such a change in the equilibrium pressure became less remarkable with increasing temperature. These experimental results agreed with the thermodynamic calculation based on magnetic data. (author)

  4. Hydrogen Education Curriculum Path at Michigan Technological University

    Energy Technology Data Exchange (ETDEWEB)

    Keith, Jason; Crowl, Daniel; Caspary, David; Naber, Jeff; Allen, Jeff; Mukerjee, Abhijit; Meng, Desheng; Lukowski, John; Solomon, Barry; Meldrum, Jay

    2012-01-03

    The objective of this project was four-fold. First, we developed new courses in alternative energy and hydrogen laboratory and update existing courses in fuel cells. Secondly, we developed hydrogen technology degree programs. Thirdly, we developed hydrogen technology related course material for core courses in chemical engineering, mechanical engineering, and electrical engineering. Finally, we developed fuel cell subject material to supplement the Felder & Rousseau and the Geankoplis chemical engineering undergraduate textbooks.

  5. Deuterium isotope effects on 13C chemical shifts of 10-Hydroxybenzo[h]quinolines

    DEFF Research Database (Denmark)

    Hansen, Poul Erik; Kamounah, Fadhil S.; Gryko, Daniel T.

    2013-01-01

    Deuterium isotope effects on 13C-NMR chemical shifts are investigated in a series of 10-hydroxybenzo[h]quinolines (HBQ’s) The OH proton is deuteriated. The isotope effects on 13C chemical shifts in these hydrogen bonded systems are rather unusual. The formal four-bond effects are found to be nega...

  6. Chemical equilibrium of hydrogen and aqueous solutions of 1 : 1 bicarbonate and formate salts with a common cation

    NARCIS (Netherlands)

    Engel, D.C.; Versteeg, G.F.; Swaaij, W.P.M. van

    1997-01-01

    The chemical equilibrium of hydrogen and aqueous solutions of 1:1 bicarbonate and formate salts with a common cation has been investigated in an intensively stirred batch reactor: MHCO3(aq) + H2(aq) ↔ MOOCH(aq) + H2O(l) This was accomplished for the sodium (M = Na), potassium (M = K) and ammonium (M

  7. Deciphering the "chemical" nature of the exotic isotopes of hydrogen by the MC-QTAIM analysis: the positively charged muon and the muonic helium as new members of the periodic table.

    Science.gov (United States)

    Goli, Mohammad; Shahbazian, Shant

    2014-04-14

    This report is a primarily survey on the chemical nature of some exotic species containing the positively charged muon and the muonic helium, i.e., the negatively charged muon plus helium nucleus, as exotic isotopes of hydrogen, using the newly developed multi-component quantum theory of atoms in molecules (MC-QTAIM) analysis, employing ab initio non-Born-Oppenhiemer wavefunctions. Accordingly, the "atoms in molecules" analysis performed on various asymmetric exotic isotopomers of the hydrogen molecule, recently detected experimentally [Science, 2011, 331, 448], demonstrates that both the exotic isotopes are capable of forming atoms in molecules and retaining the identity of hydrogen atoms. Various derived properties of atomic basins containing the muonic helium cast no doubt that apart from its short life time, it is a heavier isotope of hydrogen while the properties of basins containing the positively charged muon are more remote from those of the orthodox hydrogen basins, capable of appreciable donation of electrons as well as large charge polarization. However, with some tolerance, they may also be categorized as hydrogen basins though with a smaller electronegativity. All in all, the present study also clearly demonstrates that the MC-QTAIM analysis is an efficient approach to decipher the chemical nature of species containing exotic constituents, which are difficult to elucidate by experimental and/or alternative theoretical schemes.

  8. SISGR - Hydrogen Caged in Carbon-Exploration of Novel Carbon-Hydrogen Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Lueking, Angela [Pennsylvania State Univ., State College, PA (United States); Badding, John [Pennsylvania State Univ., State College, PA (United States); Crespi, Vinent [Pennsylvania State Univ., State College, PA (United States)

    2015-12-01

    Hydrogen trapped in a carbon cage, captured through repulsive interactions, is a novel concept in hydrogen storage. Trapping hydrogen via repulsive interactions borrows an idea from macroscale hydrogen storage (i.e. compressed gas storage tanks) and reapplies these concepts on the nanoscale in specially designed molecular containers. Under extreme conditions of pressure, hydrogen solubility in carbon materials is expected to increase and carbon is expected to restructure to minimize volume via a mixed sp2/sp3 hydrogenated state. Thermodynamics dictate that pre-formed C-H structures will rearrange with increased pressure, yet the final carbon-hydrogen interactions may be dependent upon the mechanism by which hydrogen is introduced. Gas “trapping” is meant to denote gas present in a solid in a high density, adsorbed-like state, when the external pressure is much less than that necessary to provide a comparable fluid density. Trapping thus denotes a kinetically metastable state rather than thermodynamic equilibrium. This project probed mechanochemical means to polymerize select hydrocarbons in the presence of gases, in an attempt to form localized carbon cages that trap gases via repulsive interactions. Aromatic, polyaromatic, and hydroaromatic molecules expected to undergo cyclo-addition reactions were polymerized at high (~GPa) pressures to form extended hydrogenated amorphous carbon networks. Notably, aromatics with a pre-existing internal free volume (such as Triptycene) appeared to retain an internal porosity upon application of pressure. However, a high photoluminescence background after polymerization precluded in situ identification of trapped gases. No spectroscopic evidence was found after depressurization that would be indicative of pockets of trapped gases in a localized high-pressure environment. Control studies suggested this measurement may be insensitive to gases at low pressure. Similarly, no spectral fingerprint was found for gas-imbued spherical

  9. Chemical warfare agents identification by thermal neutron detection

    International Nuclear Information System (INIS)

    Liu Boxue; Ai Xianyun; Tan Daoyuan; Zhang Dianqin

    2000-01-01

    The hydrogen concentration determination by thermal neutron detection is a non-destructive, fast and effective method to identify chemical warfare agents and TNT that contain different hydrogen fraction. When an isotropic neutron source is used to irradiate chemical ammunition, hydrogen atoms of the agent inside shell act as a moderator and slow down neutrons. The number of induced thermal neutrons depends mainly upon hydrogen content of the agent. Therefore measurement of thermal neutron influence can be used to determine hydrogen atom concentration, thereby to determine the chemical warfare agents. Under a certain geometry three calibration curves of count rate against hydrogen concentration were measured. According to the calibration curves, response of a chemical agent or TNT could be calculated. Differences of count rate among chemical agents and TNT for each kind of shells is greater than five times of standard deviations of count rate for any agent, so chemical agents or TNT could be identified correctly. Meanwhile, blast tube or liquid level of chemical warfare agent could affect the response of thermal neutron count rate, and thereby the result of identification. (author)

  10. Beneficial effect of carbon on hydrogen desorption kinetics from Mg–Ni–In alloy

    International Nuclear Information System (INIS)

    Cermak, J.; Kral, L.

    2013-01-01

    Highlights: ► Beneficial effect of graphitic carbon was observed. ► The effect is optimal up to c opt . ► Above c opt , phase decomposition occurs. ► Indium in studied Mg–Ni-based alloys prevents oxidation. - Abstract: In the present paper, hydrogen desorption kinetics from hydrided Mg–Ni–In–C alloys was investigated. A chemical composition that substantially accelerates hydrogen desorption was found. It was observed that carbon improves the hydrogen desorption kinetics significantly. Its beneficial effect was found to be optimum close to the carbon concentration of about c C ≅ 5 wt.%. With this composition, stored hydrogen can be desorbed readily at temperatures down to about 485 K, immediately after hydrogen charging. This can substantially shorten the hydrogen charging/discharging cycle of storage tanks using Mg–Ni-based alloys as hydrogen storage medium. For higher carbon concentrations, unwanted phases precipitated, likely resulting in deceleration of hydrogen desorption and lower hydrogen storage capacity.

  11. Physical, chemical and microbiological properties of mixed hydrogenated palm kernel oil and cold-pressed rice bran oil as ingredients in non-dairy creamer

    Directory of Open Access Journals (Sweden)

    Kunakorn Katsri

    2014-02-01

    Full Text Available The physical, chemical and microbiological properties of hydrogenated palm kernel oil (PKO and cold-pressed rice bran oil (RBOas ingredients in the production of liquid and powdered non-dairy creamer (coffee whitener were studied. The mixing ratios between hydrogenated PKO and cold-pressed RBO were statistically designed as of 100:0, 90:10,80:20, 70:30, 60:40, 50:50, 40:60, 30:70, 20:80, 10:90 and 0:100.The color, absorbanceand viscosity of the mixtures were investigated. As the ratio of cold-pressed RBO increased, the color became darker (L*of 93.06 to 86.25 and the absorbance significantly increased, while the viscosity of the mixtures of 20:80, 10:90 and 0:100 (54 cp. were the highest amongst the ratios tested.The hydrogenated PKO and cold-pressed RBO mixtures were further chemically tested for fatty acids, -oryzanol, -tocopherol, trans-fat contents andantioxidant activity. There were 10 fatty acids present in hydrogenated PKO with saturated fatty acid being the most predominant. Comparatively, there were only 5 fatty acids found in cold-pressed RBO with monounsaturated fatty acid being the major fatty acid. -Oryzanol and -tocopherol contents were higher with increasingcold-pressed RBO from 0-100% (0 to 1,155.00 mg/100g oil and 0.09 to 30.82 mg/100g oil, respectively. Antioxidant activity was increased with increasing cold-pressed RBO from 0-100% (9.26 to 94.24%.The pure hydrogenated PKO contained higher trans-fat content than that of the 90:10 and 80:20 mixtures (2.73, 1.93 and 1.85mg/100g oil,respectively while other samples had no trans-fat. No microorganisms were present in any of the samples.Therefore, substitution of hydrogenated PKO by cold-pressed RBO from 30-100% would offer more nutritional values and better chemical and physical properties of non-dairy creamer.

  12. Hydrogen demonstration projects options in the Netherlands. Final report

    International Nuclear Information System (INIS)

    Bergsma, G.C.; Van der Werff, T.T.; Rooijers, F.J.

    1996-01-01

    Based on a survey of hydrogen demonstration projects, contacts with different actors and discussions in a sounding board for the study on the title subject, it is concluded that a conference can be organized where the possibilities of setting up hydrogen demonstration projects in the Netherlands can be discussed. The following projects offer good chances to be realized in the next few years: large-scale CO 2 storage in the underground, applying enhanced gas recovery. It appears to be a relatively cheap CO 2 emission reduction measure with a large potential. It can be combined with a hydrogen mixing project with the sale of hydrogen as a so-called eco-gas to consumers. There is little interest in the other options for CO 2 storage at coal gasification and the prompt supply of 100% H 2 to small-scale consumers. Hydrogen for cogeneration, fuel cells in the industry, hydrogen in road transport and hydrogen as a storage medium are projects in which some actors are interested. Hydrogen for air transport has a large potential to which only few parties in the Netherlands can anticipate. Hydrogen demonstration projects will show important surplus value when it is supported by a hydrogen research program. Such a program can be carried out in cooperation with several other programmes of the International Energy Agency, in Japan, Germany and a number of research programs of the Netherlands Agency for Energy and the Environment (Novem). 10 figs., 4 tabs., 33 refs

  13. Possibilities of hydrogen removal

    International Nuclear Information System (INIS)

    Langer, G.; Koehling, A.; Nikodem, H.

    1982-12-01

    In the event of hypothetical severe accidents in light-water reactors, considerable amounts of hydrogen may be produced and released into the containment. Combustion of the hydrogen may jeopardize the integrity of the containment. The study reported here aimed to identify methods to mitigate the hydrogen problem. These methods should either prevent hydrogen combustion, or limit its effects. The following methods have been investigated: pre-inerting; chemical oxygen absorption; removal of oxygen by combustion; post-inerting with N 2 , CO 2 , or halon; aqueous foam; water fog; deliberate ignition; containment purging; and containment venting. The present state of the art in both nuclear and non-nuclear facilities, has been identified. The assessment of the methods was based on accident scenarios assuming significant release of hydrogen and the spectrum of requirements derived from these scenarios was used to determine the advantages and drawbacks of the various methods, assuming their application in a pressurized-water reactor of German design. (orig.) [de

  14. Isotope dependence of chemical erosion of carbon

    International Nuclear Information System (INIS)

    Reinhold, C.O.; Krstic, P.S.; Stuart, S.J.; Zhang, H.; Harris, P.R.; Meyer, F.W.

    2010-01-01

    We study the chemical erosion of hydrogen-supersaturated carbon due to bombardment by hydrogen isotopes H, D, and T at energies of 1-30 eV using classical molecular dynamics simulations. The chemical structure at the hydrogen-saturated interface (the distribution of terminal hydrocarbon moieties, in particular) shows a weak dependence on the mass of the impinging atoms. However, the sputtering yields increase considerably with increasing projectile mass. We analyze the threshold energies of chemical sputtering reaction channels and show that they are nearly mass independent, as expected from elementary bond-breaking chemical reactions involving hydrocarbons. Chemical sputtering yields for D impact are compared with new experimental data. Good agreement is found for small hydrocarbons but the simulations overestimate the production of large hydrocarbons for energies larger than 15 eV. We present a thorough analysis of the dependence of our simulations on the parameters of the bombardment schemes and discuss open questions and possible avenues for development.

  15. Binderless board and moulded products produced from whole coconut husks

    NARCIS (Netherlands)

    Dam, van J.E.G.; Snijder, M.H.B.

    2002-01-01

    A simple and efficient technology has been developed to produce high strength - high density board materials from whole coconut husks, without the addition of chemical binders. The board material has been shown to exhibit excellent properties, which are comparable with or even superior to commercial

  16. Nanocrystalline Porous Hydrogen Storage Based on Vanadium and Titanium Nitrides

    Directory of Open Access Journals (Sweden)

    A. Goncharov

    2017-01-01

    Full Text Available This review summarizes results of our study of the application of ion-beam assisted deposition (IBAD technology for creation of nanoporous thin-film structures that can absorb more than 6 wt.% of hydrogen. Data of mathematical modeling are presented highlighting the structure formation and component creation of the films during their deposition at the time of simultaneous bombardment by mixed beam of nitrogen and helium ions with energy of 30 keV. Results of high-resolution transmission electron microscopy revealed that VNx films consist of 150–200 nm particles, boundaries of which contain nanopores of 10–15 nm diameters. Particles themselves consist of randomly oriented 10–20 nm nanograins. Grain boundaries also contain nanopores (3–8 nm. Examination of the absorption characteristics of VNx, TiNx, and (V,TiNx films showed that the amount of absorbed hydrogen depends very little on the chemical composition of films, but it is determined by the structure pore. The amount of absorbed hydrogen at 0.3 MPa and 20°C is 6-7 wt.%, whereas the bulk of hydrogen is accumulated in the grain boundaries and pores. Films begin to release hydrogen even at 50°C, and it is desorbed completely at the temperature range of 50–250°C. It was found that the electrical resistance of films during the hydrogen desorption increases 104 times.

  17. Numerical analysis on hydrogen stratification and post-inerting of hydrogen risk

    International Nuclear Information System (INIS)

    Peng, Cheng; Tong, Lili; Cao, Xuewu

    2016-01-01

    Highlights: • A three-dimensional computational model was built and the applicability was discussed. • The formation of helium stratification was further studied. • Three influencing factors on the post-inerting of hydrogen risk were analyzed. - Abstract: In the case of severe accidents, the risk of hydrogen explosion threatens the integrity of the nuclear reactor containment. According to nuclear regulations, hydrogen control is required to ensure the safe operation of the nuclear reactor. In this study, the method of Computational Fluid Dynamics (CFD) has been applied to analyze process of hydrogen stratification and the post-inerting of hydrogen risk in the Large-Scale Gas Mixing Facility. A three-dimensional computational model was built and the applicability of different turbulence models was discussed. The result shows that the helium concentration calculated by the standard k–ε turbulence model is closest to the experiment data. Through analyzing the formation of helium stratification at different injection velocities, it is found that when the injection mass flow is constant and the injection velocity of helium increases, the mixture of helium and air is enhanced while there is rarely influence on the formation of helium stratification. In addition, the influences of mass flow rate, injection location and direction and inert gas on the post-inerting of hydrogen risk have been analyzed and the results are as follows: with the increasing of mass flow rate, the mitigation effect of nitrogen on hydrogen risk will be further improved; there is an obvious local difference between the mitigation effects of nitrogen on hydrogen risk in different injection directions and locations; when the inert gas is injected at the same mass flow rate, the mitigation effect of steam on hydrogen risk is better than that of nitrogen. This study can provide technical support for the mitigation of hydrogen risk in the small LWR containment.

  18. Hydrogen Sensors Boost Hybrids; Today's Models Losing Gas?

    Science.gov (United States)

    2005-01-01

    Advanced chemical sensors are used in aeronautic and space applications to provide safety monitoring, emission monitoring, and fire detection. In order to fully do their jobs, these sensors must be able to operate in a range of environments. NASA has developed sensor technologies addressing these needs with the intent of improving safety, optimizing combustion efficiencies, and controlling emissions. On the ground, the chemical sensors were developed by NASA engineers to detect potential hydrogen leaks during Space Shuttle launch operations. The Space Shuttle uses a combination of hydrogen and oxygen as fuel for its main engines. Liquid hydrogen is pumped to the external tank from a storage tank located several hundred feet away. Any hydrogen leak could potentially result in a hydrogen fire, which is invisible to the naked eye. It is important to detect the presence of a hydrogen fire in order to prevent a major accident. In the air, the same hydrogen-leak dangers are present. Stress and temperature changes can cause tiny cracks or holes to form in the tubes that line the Space Shuttle s main engine nozzle. Such defects could allow the hydrogen that is pumped through the nozzle during firing to escape. Responding to the challenges associated with pinpointing hydrogen leaks, NASA endeavored to improve propellant leak-detection capabilities during assembly, pre-launch operations, and flight. The objective was to reduce the operational cost of assembling and maintaining hydrogen delivery systems with automated detection systems. In particular, efforts have been focused on developing an automated hydrogen leak-detection system using multiple, networked hydrogen sensors that are operable in harsh conditions.

  19. Estimation of optimal capacity of the module through the demand analysis of refinery hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Young-Seek; Kim, Ho-Jin; Kim, Il-Su [SK energy Institution of Technology, Daejeon (Korea, Republic of)] (and others)

    2006-02-15

    Hydrogen is focused as energy carrier, not an energy source on the rising of problems such as exhaustion of fossil fuel and environment pollution. Thermochemical hydrogen production by nuclear energy has potential to efficiently produce large quantities of hydrogen without producing greenhouse gases. The oil refiners and petro-chemical plant are very large, centralized producers and users of industrial hydrogen, and they a high-potential early market for hydrogen produced by nuclear energy. Therefore, hydrogen market of petro-chemical industry as demand site for nuclear hydrogen was investigated and worked for demand forecast of hydrogen in 2020. Also we suggested possible supply plans of nuclear hydrogen considered regional characteristics. The hydrogen production cost was analyzed and estimated for nuclear hydrogen as well as conventional hydrogen production such as natural gas reforming and coal gasification in various range.

  20. Estimation of optimal capacity of the module through the demand analysis of refinery hydrogen

    International Nuclear Information System (INIS)

    Yoon, Young-Seek; Kim, Ho-Jin; Kim, Il-Su

    2006-02-01

    Hydrogen is focused as energy carrier, not an energy source on the rising of problems such as exhaustion of fossil fuel and environment pollution. Thermochemical hydrogen production by nuclear energy has potential to efficiently produce large quantities of hydrogen without producing greenhouse gases. The oil refiners and petro-chemical plant are very large, centralized producers and users of industrial hydrogen, and they a high-potential early market for hydrogen produced by nuclear energy. Therefore, hydrogen market of petro-chemical industry as demand site for nuclear hydrogen was investigated and worked for demand forecast of hydrogen in 2020. Also we suggested possible supply plans of nuclear hydrogen considered regional characteristics. The hydrogen production cost was analyzed and estimated for nuclear hydrogen as well as conventional hydrogen production such as natural gas reforming and coal gasification in various range

  1. Novel Methods of Hydrogen Leak Detection

    International Nuclear Information System (INIS)

    Pushpinder S Puri

    2006-01-01

    For hydrogen to become a consumer fuel for automotive and domestic power generation, safety is paramount. Today's hydrogen systems are built with inherent safety measures and multiple levels of protection. However, human senses, in particular, the sense of smell, is considered the ultimate safeguards against leaks. Since hydrogen is an odorless gas, use of odorants to detect leaks, as is done in case of natural gas, is obvious solution. The odorants required for hydrogen used in fuel cells have a unique requirement which must be met. This is because almost all of the commercial odorants used in gas leak detection contain sulfur which acts as poison for the catalysts used in hydrogen based fuel cells, most specifically for the PEM (polymer electrolyte membrane or proton exchange membrane) fuel cells. A possible solution to this problem is to use non-sulfur containing odorants. Chemical compounds based on mixtures of acrylic acid and nitrogen compounds have been adopted to achieve a sulfur-free odorization of a gas. It is, therefore, desired to have a method and system for hydrogen leak detection using odorant which can incorporate a uniform concentration of odorant in the hydrogen gas, when odorants are mixed in the hydrogen storage or delivery means. It is also desired to develop methods where the odorant is not added to the bulk hydrogen, keeping it free of the odorization additives. A series of novel solutions are proposed which address the issues raised above. These solutions are divided into three categories as follows: 1. Methods incorporating an odorant in the path of hydrogen leak as opposed to adding it to the hydrogen gas. 2. Methods where odorants are generated in-situ by chemical reaction with the leaking hydrogen 3. Methods of dispensing and storing odorants in high pressure hydrogen gas which release odorants to the gas at a uniform and predetermined rates. Use of one or more of the methods described here in conjunction with appropriate engineering

  2. Thermodynamic Possibilities and Constraints of Pure Hydrogen Production by a Chromium, Nickel and Manganese-Based Chemical Looping Process at Lower Temperatures

    Czech Academy of Sciences Publication Activity Database

    Svoboda, Karel; Siewiorek, A.; Baxter, D.; Rogut, J.; Punčochář, Miroslav

    2007-01-01

    Roč. 61, č. 2 (2007), s. 110-120 ISSN 0366-6352 Institutional research plan: CEZ:AV0Z40720504 Keywords : chromium * thermodynamics * hydrogen Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 0.367, year: 2007

  3. Estimation of strength in different extra Watson-Crick hydrogen bonds in DNA double helices through quantum chemical studies.

    Science.gov (United States)

    Bandyopadhyay, D; Bhattacharyya, D

    2006-10-15

    It was shown earlier, from database analysis, model building studies, and molecular dynamics simulations that formation of cross-strand bifurcated or Extra Watson-Crick hydrogen (EWC) bonds between successive base pairs may lead to extra rigidity to DNA double helices of certain sequences. The strengths of these hydrogen bonds are debatable, however, as they do not have standard linear geometry criterion. We have therefore carried out detailed ab initio quantum chemical studies using RHF/6-31G(2d,2p) and B3LYP/6-31G(2p,2d) basis sets to determine strengths of several bent hydrogen bonds with different donor and acceptors. Interaction energy calculations, corrected for the basis set superposition errors, suggest that N-H...O type bent EWC hydrogen bonds are possible along same strands or across the strands between successive base pairs, leading to significant stability (ca. 4-9 kcal/mol). The N-H...N and C-H...O type interactions, however, are not so stabilizing. Hence, consideration of EWC N-H...O H-bonds can lead to a better understanding of DNA sequence directed structural features. Copyright (c) 2006 Wiley Periodicals, Inc.

  4. The potential impact of hydrogen energy use on the atmosphere

    Science.gov (United States)

    van Ruijven, B. J.; Lamarque, J. F.; van Vuuren, D. P.; Kram, T.; Eerens, H.

    2009-04-01

    Energy models show very different trajectories for future energy systems (partly as function of future climate policy). One possible option is a transition towards a hydrogen-based energy system. The potential impact of such hydrogen economy on atmospheric emissions is highly uncertain. On the one hand, application of hydrogen in clean fuel cells reduces emissions of local air pollutants, like SOx and NOx. On the other hand, emissions of hydrogen from system leakages are expected to change the atmospheric concentrations and behaviour (see also Price et al., 2007; Sanderson et al., 2003; Schultz et al., 2003; Tromp et al., 2003). The uncertainty arises from several sources: the expected use of hydrogen, the intensity of leakages and emissions, and the atmospheric chemical behaviour of hydrogen. Existing studies to the potential impacts of a hydrogen economy on the atmosphere mostly use hydrogen emission scenarios that are based on simple assumptions. This research combines two different modelling efforts to explore the range of impacts of hydrogen on atmospheric chemistry. First, the potential role of hydrogen in the global energy system and the related emissions of hydrogen and other air pollutants are derived from the global energy system simulation model TIMER (van Vuuren, 2007). A set of dedicated scenarios on hydrogen technology development explores the most pessimistic and optimistic cases for hydrogen deployment (van Ruijven et al., 2008; van Ruijven et al., 2007). These scenarios are combined with different assumptions on hydrogen emission factors. Second, the emissions from the TIMER model are linked to the NCAR atmospheric model (Lamarque et al., 2005; Lamarque et al., 2008), in order to determine the impacts on atmospheric chemistry. By combining an energy system model and an atmospheric model, we are able to consistently explore the boundaries of both hydrogen use, emissions and impacts on atmospheric chemistry. References: Lamarque, J.-F., Kiehl, J. T

  5. Study of interplanetary hydrogen from Lyman alpha emission and absorption determination

    International Nuclear Information System (INIS)

    Cazes, Serge.

    1979-09-01

    The purpose of the work submitted in this paper is to contribute to the study of interplanetary hydrogen from Lyman alpha emission and absorption measurements, carried out on board the D2A, OSO-8 and Copernicus satellites. This study, which was undertaken from the D2A satellite, moved us to study the interplanetary environment as from observations made from the following experiments placed on board the OSO-8 and Copernicus satellites. The experiment set up on board the OSO-8 satellite made it possible to obtain the profile of the solar alpha Lyman emission. An absorption profile was observed for the first time on these profiles and this made it possible to attribute them to interplanetary hydrogen and enabled us to make a direct and local determination of the solar ionization rate. - The spectrometer set up on board Copernicus made it possible to obtain the emission spectrum of the interplanetary environment at the same time as the geocorona. The overall velocity of the interplanetary environment was deduced from the Doppler shift between the two spectra. In the first part, the principle of the REA and POLAR experiments is recalled but only the REA experiment is described in detail, particularly the problems arising from the construction and calibration of the cell. In the second part, a study of the interplanetary environment made from the D2A determinations is presented in synthesized form. On the other hand, the study to which theses initial results led us is presented in detail. Finally, in the third part, the results obtained by means of the OSO-8 and Copernicus satellites are given [fr

  6. On the Internationalization of Corporate Boards

    DEFF Research Database (Denmark)

    Oxelheim, Lars; Gregoric, Aleksandra; Randøy, Ttrond

    Despite the global reach of their commercial activities, many multinational firms have proved slow in internationalizing their boards of directors. Based on a panel study of the internationalization of the boards of 347 non-financial firms from the Nordic countries, we find a higher fraction...... of international board membership in firms with more foreign sales, in firms with more foreign ownership and in firms whose shares are traded on foreign (mostly European) stock exchanges. Moreover, we find international directors and national directors with international experience complementary. The first......-mentioned group is found to serve a monitoring role, related to financial internationalization of the firm, whereas the latter category fills an advisory role related to commercial internationalization. Hence, different types of firm internationalization – commercial versus financial – might call for different...

  7. Equilibrium properties of dense hydrogen isotope gases based on the theory of simple fluids.

    Science.gov (United States)

    Kowalczyk, Piotr; MacElroy, J M D

    2006-08-03

    We present a new method for the prediction of the equilibrium properties of dense gases containing hydrogen isotopes. The proposed approach combines the Feynman-Hibbs effective potential method and a deconvolution scheme introduced by Weeks et al. The resulting equations of state and the chemical potentials as functions of pressure for each of the hydrogen isotope gases depend on a single set of Lennard-Jones parameters. In addition to its simplicity, the proposed method with optimized Lennard-Jones potential parameters accurately describes the equilibrium properties of hydrogen isotope fluids in the regime of moderate temperatures and pressures. The present approach should find applications in the nonlocal density functional theory of inhomogeneous quantum fluids and should also be of particular relevance to hydrogen (clean energy) storage and to the separation of quantum isotopes by novel nanomaterials.

  8. Mixed protonic-electronic conductors for hydrogen separation membranes

    Science.gov (United States)

    Song, Sun-Ju

    2003-10-01

    The chemical functionality of mixed protonic-electronic conductors arises out of the nature of the defect structure controlled by thermodynamic defect equilibria of the materials, and results in the ability to transport charged species. This dissertation is to develop a fundamental understanding of defect chemistry and transport properties of mixed protonic-electronic conducting perovskites for hydrogen separation membranes. Furthermore, it was aimed to develop the algorithm to predict how these properties affect the permeability in chemical potential gradients. From this objective, first of all, the appropriate equations governing proton incorporation into perovskite oxides were suggested and the computer simulation of defect concentrations across a membrane oxide under various conditions were performed. Electrical properties of p-type electronic defects at oxidizing conditions and n-type electrical properties of SrCe 0.95Eu0.05O3-delta at reducing atmospheres were studied. Defect equilibrium diagrams as a function of PO2 , PH2O ) produced from the Brouwer method were verified by computational simulation and electrical conductivity measurements. The chemical diffusion of hydrogen through oxide membranes was described within the framework of Wagner's chemical diffusion theory and it was solved without any simplifying assumptions on functional dependence of partial conductivity due to the successful numerical modeling of partial conductivities as a function of both hydrogen and oxygen partial pressures. Finally the hydrogen permeability of Eu and Sm doped SrCeO3-delta was studied as a function of temperature, hydrogen partial pressure gradient, and water vapor pressure gradient. The dopant dependence of hydrogen permeability was explained in terms of the difference in ionization energy and ionic radius of dopant.

  9. Hydrogen application dynamics and networks

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, E. [Air Liquide Large Industries, Champigny-sur-Marne (France)

    2010-12-30

    The Chemical Industry consumes large volumes of hydrogen as raw material for the manufacture of numerous products (e.g. polyamides and polyurethanes account for 60% of hydrogen demand). The hydrogen demand was in the recent past and will continue to be driven by the polyurethane family. China will host about 60% of new hydrogen needs over the period 2010-2015 becoming the first hydrogen market next year and reaching 25% of market share by 2015 (vs. only 4% in 2001). Air Liquide supplies large volumes of Hydrogen (and other Industrial Gases) to customers by on-site plants and through pipeline networks which offer significant benefits such as higher safety, reliability and flexibility of supply. Thanks to its long term strategy and heavy investment in large units and pipeline networks, Air Liquide is the Industrial Gas leader in most of the world class Petrochemical basins (Rotterdam, Antwerp, US Gulf Coast, Yosu, Caojing,..) (orig.)

  10. Catalytic production of hydrogen from methanol for mobile, stationary and portable fuel-cell power plants

    International Nuclear Information System (INIS)

    Lukyanov, Boris N

    2008-01-01

    Main catalytic processes for hydrogen production from methanol are considered. Various schemes of fuel processors for hydrogen production in stationary, mobile and portable power plants based on fuel cells are analysed. The attention is focussed on the design of catalytic reactors of fuel processors and on the state-of-the-art in the design of catalysts for methanol conversion, carbon monoxide steam conversion and carbon monoxide selective oxidation. Prospects for the use of methanol in on-board fuel processors are discussed.

  11. Proceedings of the fourth information exchange meeting on nuclear production of hydrogen

    International Nuclear Information System (INIS)

    2010-01-01

    scientific and technical challenges associated with the production of hydrogen using heat and/or electricity from nuclear power plants, with special emphasis on recent developments in high-temperature electrolysis and the use of different chemical thermodynamic processes. Economics and market analysis as well as safety aspects of the nuclear production of hydrogen are also discussed

  12. Hydrogen desorption from hydrogen fluoride and remote hydrogen plasma cleaned silicon carbide (0001) surfaces

    Energy Technology Data Exchange (ETDEWEB)

    King, Sean W., E-mail: sean.king@intel.com; Tanaka, Satoru; Davis, Robert F. [Department of Materials Science and Engineering, North Carolina State University, Raleigh, North Carolina 27695 (United States); Nemanich, Robert J. [Department of Physics, North Carolina State University, Raleigh, North Carolina 27695 (United States)

    2015-09-15

    Due to the extreme chemical inertness of silicon carbide (SiC), in-situ thermal desorption is commonly utilized as a means to remove surface contamination prior to initiating critical semiconductor processing steps such as epitaxy, gate dielectric formation, and contact metallization. In-situ thermal desorption and silicon sublimation has also recently become a popular method for epitaxial growth of mono and few layer graphene. Accordingly, numerous thermal desorption experiments of various processed silicon carbide surfaces have been performed, but have ignored the presence of hydrogen, which is ubiquitous throughout semiconductor processing. In this regard, the authors have performed a combined temperature programmed desorption (TPD) and x-ray photoelectron spectroscopy (XPS) investigation of the desorption of molecular hydrogen (H{sub 2}) and various other oxygen, carbon, and fluorine related species from ex-situ aqueous hydrogen fluoride (HF) and in-situ remote hydrogen plasma cleaned 6H-SiC (0001) surfaces. Using XPS, the authors observed that temperatures on the order of 700–1000 °C are needed to fully desorb C-H, C-O and Si-O species from these surfaces. However, using TPD, the authors observed H{sub 2} desorption at both lower temperatures (200–550 °C) as well as higher temperatures (>700 °C). The low temperature H{sub 2} desorption was deconvoluted into multiple desorption states that, based on similarities to H{sub 2} desorption from Si (111), were attributed to silicon mono, di, and trihydride surface species as well as hydrogen trapped by subsurface defects, steps, or dopants. The higher temperature H{sub 2} desorption was similarly attributed to H{sub 2} evolved from surface O-H groups at ∼750 °C as well as the liberation of H{sub 2} during Si-O desorption at temperatures >800 °C. These results indicate that while ex-situ aqueous HF processed 6H-SiC (0001) surfaces annealed at <700 °C remain terminated by some surface C–O and

  13. The Perceptions of Georgia School Board Members' Need for Training on School Board Governance

    Science.gov (United States)

    Nutt, Pamela Studdard

    2010-01-01

    This study explored the perceptions of training needs of school board members in Georgia. The study examined perceptions of school board chairs, board members with 1 to 5 years experience, members with 6 to 10 years experience, members with 11 to 15 years experience and board members with 16 plus years experience in the areas of school board…

  14. Templated synthesis of nickel nanoparticles: Toward heterostructured nanocomposites for efficient hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Nicholas Cole [Iowa State Univ., Ames, IA (United States)

    2013-01-01

    The world is currently facing an energy and environmental crisis for which new technologies are needed. Development of cost-competitive materials for catalysis and hydrogen storage on-board motor vehicles is crucial to lead subsequent generations into a more sustainable and energy independent future. This thesis presents work toward the scalable synthesis of bimetallic heterostructures that can enable hydrogen to compete with carbonaceous fuels by meeting the necessary gravimetric and volumetric energy densities and by enhancing hydrogen sorption/desorption kinetics near ambient temperatures and pressures. Utilizing the well-known phenomenon of hydrogen spillover, these bimetallic heterostructures could work by lowering the activation energy for hydrogenation and dehydrogenation of metals. Herein, we report a novel method for the scalable synthesis of silica templated zero-valent nickel particles (Ni$\\subset$ SiO2) that hold promise for the synthesis of nickel nanorods for use in bimetallic heterostructures for hydrogen storage. Our synthesis proceeds by chemical reduction of a nickel-hydrazine complex with sodium borohydride followed by calcination under hydrogen gas to yield silica encapsulated nickel particles. Transmission electron microscopy and powder X-ray diffraction were used to characterize the general morphology of the resultant nanocapsules as well as the crystalline phases of the incorporated Ni0 nanocrystals. The structures display strong magnetic behavior at room temperature and preliminary data suggests nickel particle size can be controlled by varying the amount of nickel precursor used in the synthesis. Calcination under different environments and TEM analysis provides evidence for an atomic migration mechanism of particle formation. Ni$\\subset$SiO2 nanocapsules were used as seeds to induce heterogeneous nucleation and subsequent growth within the nanocapsule via electroless nickel plating. Nickel nanoparticle

  15. Study on substrate metabolism process of saline waste sludge and its biological hydrogen production potential.

    Science.gov (United States)

    Zhang, Zengshuai; Guo, Liang; Li, Qianqian; Zhao, Yangguo; Gao, Mengchun; She, Zonglian

    2017-07-01

    With the increasing of high saline waste sludge production, the treatment and utilization of saline waste sludge attracted more and more attention. In this study, the biological hydrogen production from saline waste sludge after heating pretreatment was studied. The substrate metabolism process at different salinity condition was analyzed by the changes of soluble chemical oxygen demand (SCOD), carbohydrate and protein in extracellular polymeric substances (EPS), and dissolved organic matters (DOM). The excitation-emission matrix (EEM) with fluorescence regional integration (FRI) was also used to investigate the effect of salinity on EPS and DOM composition during hydrogen fermentation. The highest hydrogen yield of 23.6 mL H 2 /g VSS and hydrogen content of 77.6% were obtained at 0.0% salinity condition. The salinity could influence the hydrogen production and substrate metabolism of waste sludge.

  16. The Different Sensitive Behaviors of a Hydrogen-Bond Acidic Polymer-Coated SAW Sensor for Chemical Warfare Agents and Their Simulants

    Directory of Open Access Journals (Sweden)

    Yin Long

    2015-07-01

    Full Text Available A linear hydrogen-bond acidic (HBA linear functionalized polymer (PLF, was deposited onto a bare surface acoustic wave (SAW device to fabricate a chemical sensor. Real-time responses of the sensor to a series of compounds including sarin (GB, dimethyl methylphosphonate (DMMP, mustard gas (HD, chloroethyl ethyl sulphide (2-CEES, 1,5-dichloropentane (DCP and some organic solvents were studied. The results show that the sensor is highly sensitive to GB and DMMP, and has low sensitivity to HD and DCP, as expected. However, the sensor possesses an unexpected high sensitivity toward 2-CEES. This good sensing performance can’t be solely or mainly attributed to the dipole-dipole interaction since the sensor is not sensitive to some high polarity solvents. We believe the lone pair electrons around the sulphur atom of 2-CEES provide an electron-rich site, which facilitates the formation of hydrogen bonding between PLF and 2-CEES. On the contrary, the electron cloud on the sulphur atom of the HD molecule is offset or depleted by its two neighbouring strong electron-withdrawing groups, hence, hydrogen bonding can hardly be formed.

  17. Dealloyed Ruthenium Film Catalysts for Hydrogen Generation from Chemical Hydrides

    Directory of Open Access Journals (Sweden)

    Ramis B. Serin

    2017-07-01

    Full Text Available Thin-film ruthenium (Ru and copper (Cu binary alloys have been prepared on a Teflon™ backing layer by cosputtering of the precious and nonprecious metals, respectively. Alloys were then selectively dealloyed by sulfuric acid as an etchant, and their hydrogen generation catalysts performances were evaluated. Sputtering time and power of Cu atoms have been varied in order to tailor the hydrogen generation performances. Similarly, dealloying time and the sulfuric acid concentration have also been altered to tune the morphologies of the resulted films. A maximum hydrogen generation rate of 35 mL min−1 was achieved when Cu sputtering power and time were 200 W and 60 min and while acid concentration and dealloying time were 18 M and 90 min, respectively. It has also been demonstrated that the Ru content in the alloy after dealloying gradually increased with the increasing the sputtering power of Cu. After 90 min dealloying, the Ru to Cu ratio increased to about 190 times that of bare alloy. This is the key issue for observing higher catalytic activity. Interestingly, we have also presented template-free nanoforest-like structure formation within the context of one-step alloying and dealloying used in this study. Last but not least, the long-time hydrogen generation performances of the catalysts system have also been evaluated along 3600 min. During the first 600 min, the catalytic activity was quite stable, while about 24% of the catalytic activity decayed after 3000 min, which still makes these systems available for the development of robust catalyst systems in the area of hydrogen generation.

  18. Combined heat and power (cogeneration) plant based on renewable energy sources and electrochemical hydrogen systems

    Science.gov (United States)

    Grigor'ev, S. A.; Grigor'ev, A. S.; Kuleshov, N. V.; Fateev, V. N.; Kuleshov, V. N.

    2015-02-01

    The layout of a combined heat and power (cogeneration) plant based on renewable energy sources (RESs) and hydrogen electrochemical systems for the accumulation of energy via the direct and inverse conversion of the electrical energy from RESs into the chemical energy of hydrogen with the storage of the latter is described. Some efficient technical solutions on the use of electrochemical hydrogen systems in power engineering for the storage of energy with a cyclic energy conversion efficiency of more than 40% are proposed. It is shown that the storage of energy in the form of hydrogen is environmentally safe and considerably surpasses traditional accumulator batteries by its capacitance characteristics, being especially topical in the prolonged absence of energy supply from RESs, e.g., under the conditions of polar night and breathless weather. To provide the required heat consumption of an object during the peak period, it is proposed to burn some hydrogen in a boiler house.

  19. Supersonic Combustion of Hydrogen Jets System in Hypersonic Stream

    International Nuclear Information System (INIS)

    Zhapbasbaev, U.K.; Makashev, E.P.

    2003-01-01

    The data of calculated theoretical investigations of diffusive combustion of plane supersonic hydrogen jets in hypersonic stream received with Navier-Stokes parabola equations closed by one-para metrical (k-l) model of turbulence and multiply staged mechanism of hydrogen oxidation are given. Combustion mechanisms depending on the operating parameters are discussing. The influences of air stream composition and ways off fuel feed to the length of ignition delay and level quantity of hydrogen bum-out have been defined. The calculated theoretical results of investigations permit to make the next conclusions: 1. The diffusive combustion of the system of plane supersonic hydrogen jets in hypersonic flow happens in the cellular structures with alternation zones of intensive running of chemical reactions with their inhibition zones. 2. Gas dynamic and heat Mach waves cause a large - scale viscous formation intensifying mixing of fuel with oxidizer. 3. The system ignition of plane supersonic hydrogen jets in hypersonic airy co-flow happens with the formation of normal flame front of hydrogen airy mixture with transition to the diffusive combustion. 4. The presence of active particles in the flow composition initiates the ignition of hydrogen - airy mixture, provides the intensive running of chemical reactions and shortens the length of ignition delay. 5. The supersonic combustion of hydrogel-airy mixture is characterized by two zones: the intensive chemical reactions with an active energy heat release is occurring in the first zone and in the second - a slow hydrogen combustion limited by the mixing of fuel with oxidizer. (author)

  20. Functional nanometers for hydrogen storage produced by ball milling

    Energy Technology Data Exchange (ETDEWEB)

    Czujko, T. [Waterloo Univ., ON (Canada). Dept. of Mechanical and Mechatronics Engineering]|[Military Univ. of Technology, Warsaw (Poland). Dept. of Advanced Materials and Technologies; Varin, R.A. [Waterloo Univ., ON (Canada). Dept. of Mechanical and Mechatronics Engineering; Wronski, Z.S. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Energy Technology Centre, Hydrogen Fuel Cells and Transportation; Zaranski, Z. [Military Univ. of Technology, Warsaw (Poland). Dept. of Advanced Materials and Technologies

    2008-07-01

    It is becoming increasingly important to switch to cleaner alternative energy carriers such as hydrogen, as environmental concerns over greenhouse gas emissions from the burning of fossil fuel increase. Specifically, there is a need for efficient on-board hydrogen storage technologies for vehicular applications. This paper discussed three different methods of hydrogen desorption temperature reduction and desorption kinetics of nanostructured hydrides. The first method was based on substantial hydride particle size refinement. The second method utilized catalytic effects of nanometric n-alumina (Al{sub 2}O{sub 3}), n-yttrium oxide powder (Y{sub 2}O{sub 3}) and n-nickel (Ni) additives. The third method was based on a composite of nanohydride mixtures. The composite approach was applied to the magnesium hydride (MgH{sub 2}) plus sodium tetrahydridoborate (NaBH{sub 4}) and lithium aluminum hydride (LiAlH{sub 4}) systems. The paper presented the effects of nanostructuring and nanocatalytic additives on Mg hydride desorption properties as well as a composite behaviour of nanostructured complex hydrides. It was concluded that milling of commercial MgH{sub 2} with the nano-oxide additives had a limited effect on improving the hydrogen storage properties. The addition of specialty Inco nanometric Ni reduced the hydrogen desorption temperature considerably. 28 refs., 1 tab., 9 figs.

  1. Complex Hydrides for Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    Slattery, Darlene; Hampton, Michael

    2003-03-10

    This report describes research into the use of complex hydrides for hydrogen storage. The synthesis of a number of alanates, (AIH4) compounds, was investigated. Both wet chemical and mechano-chemical methods were studied.

  2. Rapid protein fold determination using secondary chemical shifts and cross-hydrogen bond 15N-13C’ scalar couplings (3hbJNC’)

    NARCIS (Netherlands)

    Bonvin, A.M.J.J.; Houben, K.; Guenneugues, M.N.L.; Kaptein, R.; Boelens, R.

    2001-01-01

    The possibility of generating protein folds at the stage of backbone assignment using structural restraints derived from experimentally measured cross-hydrogen bond scalar couplings and secondary chemical shift information is investigated using as a test case the small alpha/beta protein

  3. Production of bioelectricity, bio-hydrogen, high value chemicals and bioinspired nanomaterials by electrochemically active biofilms.

    Science.gov (United States)

    Kalathil, Shafeer; Khan, Mohammad Mansoob; Lee, Jintae; Cho, Moo Hwan

    2013-11-01

    Microorganisms naturally form biofilms on solid surfaces for their mutual benefits including protection from environmental stresses caused by contaminants, nutritional depletion or imbalances. The biofilms are normally dangerous to human health due to their inherited robustness. On the other hand, a recent study suggested that electrochemically active biofilms (EABs) generated by electrically active microorganisms have properties that can be used to catalyze or control the electrochemical reactions in a range of fields, such as bioenergy production, bioremediation, chemical/biological synthesis, bio-corrosion mitigation and biosensor development. EABs have attracted considerable attraction in bioelectrochemical systems (BESs), such as microbial fuel cells and microbial electrolysis cells, where they act as living bioanode or biocathode catalysts. Recently, it was reported that EABs can be used to synthesize metal nanoparticles and metal nanocomposites. The EAB-mediated synthesis of metal and metal-semiconductor nanocomposites is expected to provide a new avenue for the greener synthesis of nanomaterials with high efficiency and speed than other synthetic methods. This review covers the general introduction of EABs, as well as the applications of EABs in BESs, and the production of bio-hydrogen, high value chemicals and bio-inspired nanomaterials. Copyright © 2013 Elsevier Inc. All rights reserved.

  4. Defect studies of ZnO single crystals electrochemically doped with hydrogen

    Science.gov (United States)

    Čížek, J.; Žaludová, N.; Vlach, M.; Daniš, S.; Kuriplach, J.; Procházka, I.; Brauer, G.; Anwand, W.; Grambole, D.; Skorupa, W.; Gemma, R.; Kirchheim, R.; Pundt, A.

    2008-03-01

    Various defect studies of hydrothermally grown (0001) oriented ZnO crystals electrochemically doped with hydrogen are presented. The hydrogen content in the crystals is determined by nuclear reaction analysis and it is found that already 0.3at.% H exists in chemically bound form in the virgin ZnO crystals. A single positron lifetime of 182ps is detected in the virgin crystals and attributed to saturated positron trapping at Zn vacancies surrounded by hydrogen atoms. It is demonstrated that a very high amount of hydrogen (up to ˜30at.%) can be introduced into the crystals by electrochemical doping. More than half of this amount is chemically bound, i.e., incorporated into the ZnO crystal lattice. This drastic increase of the hydrogen concentration is of marginal impact on the measured positron lifetime, whereas a contribution of positrons annihilated by electrons belonging to O-H bonds formed in the hydrogen doped crystal is found in coincidence Doppler broadening spectra. The formation of hexagonal shape pyramids on the surface of the hydrogen doped crystals by optical microscopy is observed and discussed.

  5. Integrating large-scale cogeneration of hydrogen and electricity from wind and nuclear sources (NUWINDTM)

    International Nuclear Information System (INIS)

    Miller, A. I.; Duffey, R. B.

    2008-01-01

    As carbon-free fuels, hydrogen and electricity are headed for major roles in replacing hydrocarbons as the world constrains carbon dioxide (CO 2 ) emissions. This will apply particularly to the transport sector. A general trend toward electric drive on-board vehicles is already evident and hydrogen converted to electricity by a fuel cell is likely to be a major source of on-board electricity. The major car manufacturers continue to invest heavily in this option and significant government initiatives in both the USA and Canada are beginning demonstration deployments of the infrastructure needed for hydrogen refueling. However, early adoption of hydrogen as a transport fuel may well be concentrated on heavy-duty transportation: trains, ships and trucks, where battery storage of electricity is unlikely to be practical. But both hydrogen and electricity are secondary fuels and are only effective if the source of the primary energy is a low CO 2 emitter such as nuclear and wind. A competitive cost is also essential and, to achieve this, one must rely on off-peak electricity prices. This paper examines historical data for electricity prices and the actual output of the main wind farms in Ontario to show how nuclear and wind can be combined to generate hydrogen by water electrolysis at prices that are competitive with fossil-based hydrogen production. The NuWind TM concept depends on operating electrolysis cells over an extended range of current densities to accommodate the inherent variability of wind and of electricity prices as they vary in open markets. The cost of co-producing hydrogen with electricity originating from nuclear plants (80%) and from wind turbines (20%) is very close to that of production from a constantly available electricity source. In contrast, the price of hydrogen produced using electricity from wind alone is estimated to cost about $1500/tonne more than hydrogen from NuWind or nuclear alone because the electrolysis facility must be much larger

  6. Board effectiveness: Investigating payment asymmetry between board members and shareholders

    Directory of Open Access Journals (Sweden)

    Wuchun Chi

    2008-01-01

    Full Text Available Board members may well be responsible for dissension between themselves and shareholders since they are simultaneously the setters and receivers of both board remuneration and dividends. They may act out of their own personal interests at the expense of external shareholders. We investigate the impact of ownership structure, board structure and control deviation on payment asymmetry, where excessively high remuneration is paid to board members but considerably lower dividends are distributed to shareholders. We find strong evidence confirming that the smaller the shareholdings of board members and outside blockholders are, the more asymmetric the payments are. With controlling family members on the board and a higher percentage of seats held by independent board members, there is a slight reduction in the likelihood and severity of payment asymmetry. In addition, it is abundantly clear that the larger the board seat-control deviation is, the greater is the likelihood and severity of payment asymmetry. While prior research has primarily focused on board-manager agency issues, the board-shareholder perspective could be even more important in that it is the board that is the most directly delegated agent of shareholders, not the managers

  7. Process chemistry related to hydrogen isotopes

    International Nuclear Information System (INIS)

    Iwasaki, Matae; Ogata, Yukio

    1991-01-01

    Hydrogen isotopes, that is, protium, deuterium and tritium, are all related deeply to energy in engineering region. Deuterium and tritium exist usually as water in extremely thin state. Accordingly, the improvement of the technology for separating these isotopes is a large engineering subject. Further, tritium is radioactive and its half-life period is 12.26 years, therefore, it is desirable to fix it in more stable form besides its confinement in the handling system. As the chemical forms of hydrogen, the molecular hydrogen with highest reactivity, metal hydride, carbon-hydrogen-halogen system compounds, various inorganic hydrides, most stable water and hydroxides are enumerated. The grasping of the behavior from reaction to stable state of these hydrogen compounds and the related materials is the base of process chemistry. The reaction of exchanging isotopes between water and hydrogen on solid catalyzers, the decomposition of ethane halide containing hydrogen, the behavior of water and hydroxides in silicates are reported. The isotope exchange between water and hydrogen is expected to be developed as the process of separating and concentrating hydrogen isotopes. (K.I.) 103 refs

  8. On-board processing of video image sequences

    DEFF Research Database (Denmark)

    Andersen, Jakob Dahl; Chanrion, Olivier Arnaud; Forchhammer, Søren

    2008-01-01

    and evaluated. On-board there are six video cameras each capturing images of 1024times1024 pixels of 12 bpp at a frame rate of 15 fps, thus totalling 1080 Mbits/s. In comparison the average downlink data rate for these images is projected to be 50 kbit/s. This calls for efficient on-board processing to select...

  9. Effect of grade point average and enrollment in a dental hygiene National Board review course on student performance on the National Board Examination.

    Science.gov (United States)

    DeWald, Janice P; Gutmann, Marylou E; Solomon, Eric S

    2004-01-01

    Passing the National Board Dental Hygiene Examination is a requirement for licensure in all but one state. There are a number of preparation courses for the examination sponsored by corporations and dental hygiene programs. The purpose of this study was to determine if taking a board review course significantly affected student performance on the board examination. Students from the last six dental hygiene classes at Baylor College of Dentistry (n = 168) were divided into two groups depending on whether they took a particular review course. Mean entering college grade point averages (GPA), exiting dental hygiene program GPAs, and National Board scores were compared for the two groups using a t-test for independent samples (p < 0.05). No significant differences were found between the two groups for entering GPA and National Board scores. Exiting GPAs, however, were slightly higher for those not taking the course compared to those taking the course. In addition, a strong correlation (0.71, Pearson Correlation) was found between exiting GPA and National Board score. Exiting GPA was found to be a strong predictor of National Board performance. These results do not appear to support this program's participation in an external preparation course as a means of increasing students' performance on the National Board Dental Hygiene Examination.

  10. Fuel and Chemicals from Renewable Alcohols

    DEFF Research Database (Denmark)

    Hansen, Jeppe Rass

    2008-01-01

    The present work entitled Fuel and Chemicals from Renewable Alcohols covers the idea of developing routes for producing sustainable fuel and chemicals from biomass resources. Some renewable alcohols are already readily available from biomass in significant amounts and thus the potential...... for these renewable alcohols, together with other primary renewable building blocks, has been highlighted in the introductory chapter. While the first chapter covers the general potential of a renewable chemical industry, the other chapters deal with particular possibilities. It is shown how ethanol and glycerol can...... be converted into hydrogen by steam reforming over nickel or ruthenium based catalysts. This process could be important in a future hydrogen society, where hydrogen can be utilized in high efficiency fuel cells. Hydrogen produced from biofeedstocks can also be used directly in the chemical industry, where...

  11. On the chemical reaction of matter with antimatter.

    Science.gov (United States)

    Lodi Rizzini, Evandro; Venturelli, Luca; Zurlo, Nicola

    2007-06-04

    A chemical reaction between the building block antiatomic nucleus, the antiproton (p or H- in chemical notation), and the hydrogen molecular ion (H2+) has been observed by the ATHENA collaboration at CERN. The charged pair interact via the long-range Coulomb force in the environment of a Penning trap which is purpose-built to observe antiproton interactions. The net result of the very low energy collision of the pair is the creation of an antiproton-proton bound state, known as protonium (Pn), together with the liberation of a hydrogen atom. The Pn is formed in a highly excited, metastable, state with a lifetime against annihilation of around 1 micros. Effects are observed related to the temperature of the H2+ prior to the interaction, and this is discussed herein.

  12. Fiscal 1974 research report. General research on hydrogen energy subsystems; 1974 nendo suiso riyo subsystem sogoteki kento hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-03-01

    Based on the contract research 'General research on hydrogen energy subsystems and their peripheral technologies' with Agency of Industrial Science and Technology, each of 7 organizations including Denki Kagaku Kyokai (Electrochemical Association) promoted the research on hydrogen energy subsystem, combustion, fuel cell, car engine, aircraft engine, gas turbine and chemical energy, respectively. This report summarizes the research result on the former of 2 committees on hydrogen energy and peripheral technologies promoted by Denki Kagaku Kyokai. The first part describes the merit, demerit, domestic and overseas R and D states, technical problems, and future research issue for every use form of hydrogen. This part also outlines the short-, medium- and long-term prospects for use of hydrogen and oxygen energy, and describes the whole future research issue. The second part summarizes the content of each committee report. Although on details the original reports of each committee should be lead, this report is useful for obtaining the outline of utilization of hydrogen energy. (NEDO)

  13. New standard on safety for hydrogen systems in spanish. Keys for understanding and use

    Energy Technology Data Exchange (ETDEWEB)

    Luis Aprea, Jose [CNEA, Argentine Atomic Energy Commission - AAH - IRAM - Comahue University, CC 805 - Neuquen (Argentina)

    2008-07-15

    The present paper approaches all the preliminary, normative and additional elements observed during the work carried out by the Argentine standardization board to count in the country with a normative document that covers the expectations of the local community of users and other Spanish-speaking user, about the integral safety for the hydrogen systems. The antecedents and the process of adoption of an international standard and its adaptation to the local media are analyzed. The result has been the Standard IRAM/ISO 15916 that intends to offer, to all the users and especially to those who are not familiar with the technology, a base to understand the subject of safety, thus enhancing the education of the general public in hydrogen safety matters. (author)

  14. Effect of reversible hydrogen alloying and plastic deformation on microstructure development in titanium alloys

    International Nuclear Information System (INIS)

    Murzinova, M.A.

    2011-01-01

    Hydrogen leads to degradation in fracture-related mechanical properties of titanium alloys and is usually considered as a very dangerous element. Numerous studies of hydrogen interaction with titanium alloys showed that hydrogen may be considered not only as an impurity but also as temporary alloying element. This statement is based on the following. Hydrogen stabilizes high-temperature β-phase, leads to decrease in temperature of β→α transformation and extends (α + β )-phase field. The BCC β-phase exhibits lower strength and higher ductility in comparison with HCP α -phase. As a result, hydrogen improves hot workability of hard-to-deform titanium alloys. Hydrogen changes chemical composition of the phases, kinetics of phase transformations, and at low temperatures additional phase transformation (β→α + TiH 2 ) takes place, which is accompanied with noticeable change in volumes of phases. As a result, fine lamellar microstructure may be formed in hydrogenated titanium alloys after heat treatment. It was shown that controlled hydrogen alloying improves weldability and machinability of titanium alloys. After processing hydrogenated titanium preforms are subjected to vacuum annealing, and the hydrogen content decreases up to safe level. Hydrogen removal is accompanied with hydrides dissolution and β→α transformation that makes possible to control structure formation at this final step of treatment. Thus, reversible hydrogen alloying of titanium alloys allows to obtain novel microstructure with enhanced properties. The aim of the work was to study the effect of hydrogen on structure formation, namely: i) influence of hydrogen content on transformation of lamellar microstructure to globular one during deformation in (α+β)-phase field; ii) effect of dissolved hydrogen on dynamic recrystallization in single α- and β- phase regions; iii) influence of vacuum annealing temperature on microstructure development. The work was focused on the optimization of

  15. Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Kathe, Mandar [Ohio State University, Columbus, OH (United States); Xu, Dikai [Ohio State University, Columbus, OH (United States); Hsieh, Tien-Lin [Ohio State University, Columbus, OH (United States); Simpson, James [Ohio State University, Columbus, OH (United States); Statnick, Robert [Ohio State University, Columbus, OH (United States); Tong, Andrew [Ohio State University, Columbus, OH (United States); Fan, Liang-Shih [Ohio State University, Columbus, OH (United States)

    2014-12-31

    This document is the final report for the project titled “Chemical Looping Gasification for Hydrogen Enhanced Syngas Production with In-Situ CO2 Capture” under award number FE0012136 for the performance period 10/01/2013 to 12/31/2014.This project investigates the novel Ohio State chemical looping gasification technology for high efficiency, cost efficiency coal gasification for IGCC and methanol production application. The project developed an optimized oxygen carrier composition, demonstrated the feasibility of the concept and completed cold-flow model studies. WorleyParsons completed a techno-economic analysis which showed that for a coal only feed with carbon capture, the OSU CLG technology reduced the methanol required selling price by 21%, lowered the capital costs by 28%, increased coal consumption efficiency by 14%. Further, using the Ohio State Chemical Looping Gasification technology resulted in a methanol required selling price which was lower than the reference non-capture case.

  16. Hydrogen transmission/storage with a metal hydride/organic slurry

    Energy Technology Data Exchange (ETDEWEB)

    Breault, R.W.; Rolfe, J.; McClaine, A. [Thermo Power Corp., Waltham, MA (United States)

    1998-08-01

    Thermo Power Corporation has developed a new approach for the production, transmission, and storage of hydrogen. In this approach, a chemical hydride slurry is used as the hydrogen carrier and storage media. The slurry protects the hydride from unanticipated contact with moisture in the air and makes the hydride pumpable. At the point of storage and use, a chemical hydride/water reaction is used to produce high-purity hydrogen. An essential feature of this approach is the recovery and recycle of the spent hydride at centralized processing plants, resulting in an overall low cost for hydrogen. This approach has two clear benefits: it greatly improves energy transmission and storage characteristics of hydrogen as a fuel, and it produces the hydrogen carrier efficiently and economically from a low cost carbon source. The preliminary economic analysis of the process indicates that hydrogen can be produced for $3.85 per million Btu based on a carbon cost of $1.42 per million Btu and a plant sized to serve a million cars per day. This compares to current costs of approximately $9.00 per million Btu to produce hydrogen from $3.00 per million Btu natural gas, and $25 per million Btu to produce hydrogen by electrolysis from $0.05 per Kwh electricity. The present standard for production of hydrogen from renewable energy is photovoltaic-electrolysis at $100 to $150 per million Btu.

  17. Hydrogen-based electrochemical energy storage

    Science.gov (United States)

    Simpson, Lin Jay

    2013-08-06

    An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure.

  18. Investigation of the explosion hazards of hydrogen sulphide

    International Nuclear Information System (INIS)

    Saber, A.J.; Sulmistras, A.; Moen, I.O.; Thibault, P.A.

    1986-03-01

    The results of Phase I of an investigation directed towards quantifying the explosion hazards of hydrogen sulphide in air are described. The first phase is focussed on detonation in free hydrogen sulphide/air clouds. Detonation properties, including velocity and pressure, have been calculated and compared with experimental results. The observed detonation structure together with critical tube tests tests are used to assess the detonability of hydrogen sulphide/air mixtures relative to hydrogen and common hydrocarbon gases. Detailed chemical kinetic modelling of hydrogen sulphide combustion in air has been performed to correlate the detonation cell size data and to determine the influence of water vapour on the detonability of hydrogen sulphide in air. Calculations of the blast wave properties for detonation of a hydrogen sulphide/air cloud provide the data required to assess the blast effects of such explosions

  19. Studies on closed-cycle processes for hydrogen production, 3

    International Nuclear Information System (INIS)

    Sato, Shoichi; Ikezoe, Yasumasa; Shimizu, Saburo; Nakajima, Hayato; Kobayashi, Toshiaki

    1978-10-01

    Studies made in fiscal 1977 on the thermochemical and radiation chemical processes for hydrogen production are reported. In the thermochemical process, cerium (III) carbonate was used as an intermediate, and a workable process was found, which consisted of eight reaction steps. In other feasible processes, carbon dioxide was made to react with iron (II) chloride or iodide at high temperature to form carbon monoxide, and three or four reaction steps ensued. Also, an improved process of the sulfur cycle was studied. In this process, nickel salts were separated by solvent extraction. Estimated thermal efficiency (HHV) of the process was 30 - 40%, assuming 70 - 80% heat recovery. In the radiation chemical process, carbon dioxide was added with propane or nitrogen dioxide and radiolyzed: reaction mechanisms are discussed. (author)

  20. Kinetics on NiZn Bimetallic Catalysts for Hydrogen Evolution via Selective Dehydrogenation of Methylcyclohexane to Toluene

    KAUST Repository

    Shaikh Ali, Anaam

    2017-01-18

    Liquid organic chemical hydrides are effective hydrogen storage media for easy and safe transport. The chemical couple of methylcyclohexane (MCH) and toluene (TOL) has been considered one of the feasible cycles for a hydrogen carrier, but the selective dehydrogenation of MCH to TOL has been reported using only Pt-based noble metal catalysts. This study reports MCH dehydrogenation to TOL using supported NiZn as a selective, non-noble-metal catalyst. A combined experimental and computational study was conducted to provide insight into the site requirements and reaction mechanism for MCH dehydrogenation to TOL, which were compared with those for cyclohexane (CH) dehydrogenation to benzene (BZ). The kinetic measurements carried out at 300-360°C showed an almost zero order with respect to MCH pressure in the high-pressure region (≥10 kPa) and nearly a positive half order with respective to H pressure (≤40 kPa). These kinetic data for the dehydrogenation reaction paradoxically indicate that hydrogenation of a strongly chemisorbed intermediate originating from TOL is the rate-determining step. Density functional theory (DFT) calculation confirms that the dehydrogenated TOL species at the aliphatic (methyl) position group (CHCH) were strongly adsorbed on the surface, which must be hydrogenated to desorb as TOL. This hydrogen-assisted desorption mechanism explains the essential role of excess H present in the feed in maintaining the activity of the metallic surface for hydrogenation. The rate of the CH to BZ reaction was less sensitive to H pressure than that of MCH to TOL, which can be explained by the absence of a methyl group in the structure, which in turn reduces the binding energy of the adsorbed species. DFT suggests that the improved TOL selectivity by adding Zn to Ni was due to Zn atoms preferentially occupying low-coordination sites on the surface (the corner and edge sites), which are likely the unselective sites responsible for the C-C dissociation of the

  1. Kinetics on NiZn Bimetallic Catalysts for Hydrogen Evolution via Selective Dehydrogenation of Methylcyclohexane to Toluene

    KAUST Repository

    Shaikh Ali, Anaam; Jedidi, Abdesslem; Anjum, Dalaver H.; Cavallo, Luigi; Takanabe, Kazuhiro

    2017-01-01

    Liquid organic chemical hydrides are effective hydrogen storage media for easy and safe transport. The chemical couple of methylcyclohexane (MCH) and toluene (TOL) has been considered one of the feasible cycles for a hydrogen carrier, but the selective dehydrogenation of MCH to TOL has been reported using only Pt-based noble metal catalysts. This study reports MCH dehydrogenation to TOL using supported NiZn as a selective, non-noble-metal catalyst. A combined experimental and computational study was conducted to provide insight into the site requirements and reaction mechanism for MCH dehydrogenation to TOL, which were compared with those for cyclohexane (CH) dehydrogenation to benzene (BZ). The kinetic measurements carried out at 300-360°C showed an almost zero order with respect to MCH pressure in the high-pressure region (≥10 kPa) and nearly a positive half order with respective to H pressure (≤40 kPa). These kinetic data for the dehydrogenation reaction paradoxically indicate that hydrogenation of a strongly chemisorbed intermediate originating from TOL is the rate-determining step. Density functional theory (DFT) calculation confirms that the dehydrogenated TOL species at the aliphatic (methyl) position group (CHCH) were strongly adsorbed on the surface, which must be hydrogenated to desorb as TOL. This hydrogen-assisted desorption mechanism explains the essential role of excess H present in the feed in maintaining the activity of the metallic surface for hydrogenation. The rate of the CH to BZ reaction was less sensitive to H pressure than that of MCH to TOL, which can be explained by the absence of a methyl group in the structure, which in turn reduces the binding energy of the adsorbed species. DFT suggests that the improved TOL selectivity by adding Zn to Ni was due to Zn atoms preferentially occupying low-coordination sites on the surface (the corner and edge sites), which are likely the unselective sites responsible for the C-C dissociation of the

  2. Interfacial chemical bonding state and band alignment of CaF2/hydrogen-terminated diamond heterojunction

    International Nuclear Information System (INIS)

    Liu, J. W.; Liao, M. Y.; Cheng, S. H.; Imura, M.; Koide, Y.

    2013-01-01

    CaF 2 films are deposited on hydrogen-terminated diamond (H-diamond) by a radio-frequency sputter-deposition technique at room temperature. Interfacial chemical bonding state and band alignment of CaF 2 /H-diamond heterojunction are investigated by X-ray photoelectron spectroscopy. It is confirmed that there are only C-Ca bonds at the CaF 2 /H-diamond heterointerface. Valence and conductance band offsets of the CaF 2 /H-diamond heterojunciton are determined to be 3.7 ± 0.2 and 0.3 ± 0.2 eV, respectively. It shows a type I straddling band configuration. The large valence band offset suggests advantage of the CaF 2 /H-diamond heterojunciton for the development of high power and high frequency field effect transistors.

  3. A kinetic and equilibrium analysis of silicon carbide chemical vapor deposition on monofilaments

    Science.gov (United States)

    Gokoglu, S. A.; Kuczmarski, M. A.

    1993-01-01

    Chemical kinetics of atmospheric pressure silicon carbide (SiC) chemical vapor deposition (CVD) from dilute silane and propane source gases in hydrogen is numerically analyzed in a cylindrical upflow reactor designed for CVD on monofilaments. The chemical composition of the SiC deposit is assessed both from the calculated total fluxes of carbon and silicon and from chemical equilibrium considerations for the prevailing temperatures and species concentrations at and along the filament surface. The effects of gas and surface chemistry on the evolution of major gas phase species are considered in the analysis.

  4. Radiochemical analysis of Bikini ashes fallen on board the No. 5 Fukuryu Maru on March 1, 1954

    Energy Technology Data Exchange (ETDEWEB)

    Kimura, K

    1954-01-01

    Comprehensive analysis was done in order to find the proper method of medical treatment for the victim fishermen on board. Analysis was started on March 18, and ash was found to consist mostly of Ca(OH)/sub 2/, activity of which was 0.37 mc/g on April 23. Cations of the 3rd group (especially rare-earth metals) and 5th group were found to have strong activity by chemical separation. Fractions of each group, anions, Zr and Nb fraction, and U fraction were separated by an ion-exchange method.

  5. Renewable energy from biomass: a sustainable option? - Hydrogen production from alcohols

    Science.gov (United States)

    Balla, Zoltán; Kith, Károly; Tamás, András; Nagy, Orsolya

    2015-04-01

    Sustainable development requires us to find new energy sources instead of fossil fuels. One possibility is the hydrogen fuel cell, which uses significantly more efficient than the current combustion engines. The task of the hydrogen is clean, carbon-free renewable energy sources to choose in the future by growing degree. Hungary can play a role in the renewable energy sources of biomass as a renewable biomass annually mass of about 350 to 360 million tons. The biomass is only a very small proportion of fossil turn carbonaceous materials substitution, while we may utilize alternative energy sources as well. To the hydrogen production from biomass, the first step of the chemical transformations of chemical bonds are broken, which is always activation energy investment needs. The methanol and ethanol by fermentation from different agricultural products is relatively easy to produce, so these can be regarded as renewable energy carriers of. The ethanol can be used directly, and used in several places in the world are mixed with the petrol additive. This method is the disadvantage that the anhydrous alcohol is to be used in the combustion process in the engine more undesired by-products may be formed, and the fuel efficiency of the engine is significantly lower than the efficiency of the fuel cells. More useful to produce hydrogen from the alcohol and is used in a fuel cell electric power generation. Particularly attractive option for the so-called on-board reforming of alcohols, that happens immediately when the vehicle hydrogen production. It does not need a large tank of hydrogen, because the hydrogen produced would be directly to the fuel cell. The H2 tank limit use of its high cost, the significant loss evaporation, the rare-station network, production capacity and service background and lack of opportunity to refuel problems. These can be overcome, if the hydrogen in the vehicle is prepared. As volume even 700 bar only about half the H2 pressure gas can be stored

  6. Hydrogen production by enhanced-sorption chemical looping steam reforming of glycerol in moving-bed reactors

    International Nuclear Information System (INIS)

    Dou, Binlin; Song, Yongchen; Wang, Chao; Chen, Haisheng; Yang, Mingjun; Xu, Yujie

    2014-01-01

    Highlights: • New approach on continuous high-purity H 2 produced auto-thermally with long time. • Low-cost NiO/NiAl 2 O 4 exhibited high redox performance to H 2 from glycerol. • Oxidation, steam reforming, WSG and CO 2 capture were combined into a reactor. • H 2 purity of above 90% was produced without heating at 1.5–3.0 S/C and 500–600 °C. • Sorbent regeneration and catalyst oxidization achieved simultaneously in a reactor. - Abstract: The continuous high-purity hydrogen production by the enhanced-sorption chemical looping steam reforming of glycerol based on redox reactions integrated with in situ CO 2 removal has been experimentally studied. The process was carried out by a flow of catalyst and sorbent mixture using two moving-bed reactors. Various unit operations including oxidation, steam reforming, water gas shrift reaction and CO 2 removal were combined into a single reactor for hydrogen production in an overall economic and efficient process. The low-cost NiO/NiAl 2 O 4 catalyst efficiently converted glycerol and steam to H 2 by redox reactions and the CO 2 produced in the process was simultaneously removed by CaO sorbent. The best results with an enriched hydrogen product of above 90% in auto-thermal operation for reforming reactor were achieved at initial temperatures of 500–600 °C and ratios of steam to carbon (S/C) of 1.5–3.0. The results indicated also that not all of NiO in the catalyst can be reduced to Ni by the reaction with glycerol, and the reduced Ni can be oxidized to NiO by air at 900 °C. The catalyst oxidization and sorbent regeneration were achieved under the same conditions in air reactor

  7. Hydrogen gas sample environment for TOSCA

    International Nuclear Information System (INIS)

    Kibble, Mark G; Ramirez-Cuesta, Anibal J; Goodway, Chris M; Evans, Beth E; Kirichek, Oleg

    2014-01-01

    The idea of using hydrogen as a fuel has gained immense popularity over many years. Hydrogen is abundant, can be produced from renewable resources and is not a greenhouse gas. However development of hydrogen based technology is impossible without understanding of physical and chemical processes that involve hydrogen sometime in extreme conditions such as high pressure or low and high temperatures. Neutron spectroscopy allows measurement of a hydrogen atom motion in variety of samples. Here we describe and discuss a sample environment kit developed for hydrogen gas experiment in a broad range of pressure up to 7 kbar and temperatures from 4 K to 473 K. We also describe para-hydrogen rig which produces para-hydrogen gas required for studying the rotational line of molecular hydrogen

  8. ON-BOARD COMPUTER SYSTEM FOR KITSAT-1 AND 2

    Directory of Open Access Journals (Sweden)

    H. S. Kim

    1996-06-01

    Full Text Available KITSAT-1 and 2 are microsatellites weighting 50kg and all the on-board data are processed by the on-board computer system. Hence, these on-board computers require to be highly reliable and be designed with tight power consumption, mass and size constraints. On-board computer(OBC systems for KITSAT-1 and 2 are also designed with a simple flexible hardware for reliability and software takes more responsibility than hardware. KITSAT-1 and 2 on-board computer system consist of OBC 186 as the primary OBC and OBC80 as its backup. OBC186 runs spacecraft operating system (SCOS which has real-time multi-tasking capability. Since their launch, OBC186 and OBC80 have been operating successfully until today. In this paper, we describe the development of OBC186 hardware and software and analyze its in-orbit operation performance.

  9. Recycling of WEEE: Characterization of spent printed circuit boards from mobile phones and computers

    International Nuclear Information System (INIS)

    Yamane, Luciana Harue; Tavares de Moraes, Viviane; Crocce Romano Espinosa, Denise; Soares Tenorio, Jorge Alberto

    2011-01-01

    Highlights: → This paper presents new and important data on characterization of wastes of electric and electronic equipments. → Copper concentration is increasing in mobile phones and remaining constant in personal computers. → Printed circuit boards from mobile phones and computers would not be mixed prior treatment. - Abstract: This paper presents a comparison between printed circuit boards from computers and mobile phones. Since printed circuits boards are becoming more complex and smaller, the amount of materials is constantly changing. The main objective of this work was to characterize spent printed circuit boards from computers and mobile phones applying mineral processing technique to separate the metal, ceramic, and polymer fractions. The processing was performed by comminution in a hammer mill, followed by particle size analysis, and by magnetic and electrostatic separation. Aqua regia leaching, loss-on-ignition and chemical analysis (inductively coupled plasma atomic emission spectroscopy - ICP-OES) were carried out to determine the composition of printed circuit boards and the metal rich fraction. The composition of the studied mobile phones printed circuit boards (PCB-MP) was 63 wt.% metals; 24 wt.% ceramics and 13 wt.% polymers; and of the printed circuit boards from studied personal computers (PCB-PC) was 45 wt.% metals; 27 wt.% polymers and ceramics 28 wt.% ceramics. The chemical analysis showed that copper concentration in printed circuit boards from personal computers was 20 wt.% and in printed circuit boards from mobile phones was 34.5 wt.%. According to the characteristics of each type of printed circuit board, the recovery of precious metals may be the main goal of the recycling process of printed circuit boards from personal computers and the recovery of copper should be the main goal of the recycling process of printed circuit boards from mobile phones. Hence, these printed circuit boards would not be mixed prior treatment. The results

  10. Performance predictions for solar-chemical converters based on photoelectrochemical I-V curves

    Energy Technology Data Exchange (ETDEWEB)

    Luttmer, J.D.; Trachtenberg, I.

    1985-06-01

    Texas Instruments' solar energy system contains a solar-chemical converter (SCC) which converts solar energy into chemical energy via the electrolysis of hydrobromic acid (HBr) into hydrogen (H/sub 2/) and bromine (Br/sub 2/). Previous predictions of SCC performance have employed electrical dry-probe data and a computer simulation model to predict the H/sub 2/ generation rates. The method of prediction described here makes use of the photoelectrochemical Icurves to determine the ''wet'' probe parameters of V /SUB oc/ J /SUB sc/ FF, and efficiency for anodes and cathodes. The advantages of this technique over the dry-probe/computer simulation method are discussed. A comparison of predicted and measured H/sub 2/ generation rates is presented. Solar to chemical efficiencies of 8.6% have been both predicted and measured for the electrolysis of 48% HBr to hydrogen and bromine by a full anode/cathode array. Individual cathode solar to hydrogen efficiencies of 9.5% have been obtained.

  11. Development of a green bipropellant hydrogen peroxide thruster for attitude control on satellites

    Science.gov (United States)

    Woschnak, A.; Krejci, D.; Schiebl, M.; Scharlemann, C.

    2013-03-01

    This document describes the selection assessment of propellants for a 1-newton green bipropellant thruster for attitude control on satellites. The development of this thruster was conducted as a part of the project GRASP (Green Advanced Space Propellants) within the European FP7 research program. The green propellant combinations hydrogen peroxide (highly concentrated with 87.5 %(wt.)) with kerosene or hydrogen peroxide (87.5 %(wt.)) with ethanol were identified as interesting candidates and were investigated in detail with the help of an experimental combustion chamber in the chemical propulsion laboratory at the Forschungsund Technologietransfer GmbH ― Fotec. Based on the test results, a final selection of propellants was performed.

  12. Board Task Performance

    DEFF Research Database (Denmark)

    Minichilli, Alessandro; Zattoni, Alessandro; Nielsen, Sabina

    2012-01-01

    identify three board processes as micro-level determinants of board effectiveness. Specifically, we focus on effort norms, cognitive conflicts and the use of knowledge and skills as determinants of board control and advisory task performance. Further, we consider how two different institutional settings....... The findings show that: (i) Board processes have a larger potential than demographic variables to explain board task performance; (ii) board task performance differs significantly between boards operating in different contexts; and (iii) national context moderates the relationships between board processes...... and board task performance....

  13. Catalyst support effects on hydrogen spillover

    Science.gov (United States)

    Karim, Waiz; Spreafico, Clelia; Kleibert, Armin; Gobrecht, Jens; Vandevondele, Joost; Ekinci, Yasin; van Bokhoven, Jeroen A.

    2017-01-01

    Hydrogen spillover is the surface migration of activated hydrogen atoms from a metal catalyst particle, on which they are generated, onto the catalyst support. The phenomenon has been much studied and its occurrence on reducible supports such as titanium oxide is established, yet questions remain about whether hydrogen spillover can take place on nonreducible supports such as aluminium oxide. Here we use the enhanced precision of top-down nanofabrication to prepare controlled and precisely tunable model systems that allow us to quantify the efficiency and spatial extent of hydrogen spillover on both reducible and nonreducible supports. We place multiple pairs of iron oxide and platinum nanoparticles on titanium oxide and aluminium oxide supports, varying the distance between the pairs from zero to 45 nanometres with a precision of one nanometre. We then observe the extent of the reduction of the iron oxide particles by hydrogen atoms generated on the platinum using single-particle in situ X-ray absorption spectromicroscopy applied simultaneously to all particle pairs. The data, in conjunction with density functional theory calculations, reveal fast hydrogen spillover on titanium oxide that reduces remote iron oxide nanoparticles via coupled proton-electron transfer. In contrast, spillover on aluminium oxide is mediated by three-coordinated aluminium centres that also interact with water and that give rise to hydrogen mobility competing with hydrogen desorption; this results in hydrogen spillover about ten orders of magnitude slower than on titanium oxide and restricted to very short distances from the platinum particle. We anticipate that these observations will improve our understanding of hydrogen storage and catalytic reactions involving hydrogen, and that our approach to creating and probing model catalyst systems will provide opportunities for studying the origin of synergistic effects in supported catalysts that combine multiple functionalities.

  14. Review of theoretical calculations of hydrogen storage in carbon-based materials

    Energy Technology Data Exchange (ETDEWEB)

    Meregalli, V.; Parrinello, M. [Max-Planck-Institut fuer Festkoerperforschung, Stuttgart (Germany)

    2001-02-01

    In this paper we review the existing theoretical literature on hydrogen storage in single-walled nanotubes and carbon nanofibers. The reported calculations indicate a hydrogen uptake smaller than some of the more optimistic experimental results. Furthermore the calculations suggest that a variety of complex chemical processes could accompany hydrogen storage and release. (orig.)

  15. Solar Hydrogen Fuel Cell Projects at Brooklyn Tech

    Science.gov (United States)

    Fedotov, Alex; Farah, Shadia; Farley, Daithi; Ghani, Naureen; Kuo, Emmy; Aponte, Cecielo; Abrescia, Leo; Kwan, Laiyee; Khan, Ussamah; Khizner, Felix; Yam, Anthony; Sakeeb, Khan; Grey, Daniel; Anika, Zarin; Issa, Fouad; Boussayoud, Chayama; Abdeldayem, Mahmoud; Zhang, Alvin; Chen, Kelin; Chan, Kameron Chuen; Roytman, Viktor; Yee, Michael

    2010-01-01

    This article describes the projects on solar hydrogen powered vehicles using water as fuel conducted by teams at Brooklyn Technical High School. Their investigations into the pure and applied chemical thermodynamics of hydrogen fuel cells and bio-inspired devices have been consolidated in a new and emerging sub-discipline that they define as solar…

  16. Interstellar hydrogen bonding

    Science.gov (United States)

    Etim, Emmanuel E.; Gorai, Prasanta; Das, Ankan; Chakrabarti, Sandip K.; Arunan, Elangannan

    2018-06-01

    This paper reports the first extensive study of the existence and effects of interstellar hydrogen bonding. The reactions that occur on the surface of the interstellar dust grains are the dominant processes by which interstellar molecules are formed. Water molecules constitute about 70% of the interstellar ice. These water molecules serve as the platform for hydrogen bonding. High level quantum chemical simulations for the hydrogen bond interaction between 20 interstellar molecules (known and possible) and water are carried out using different ab-intio methods. It is evident that if the formation of these species is mainly governed by the ice phase reactions, there is a direct correlation between the binding energies of these complexes and the gas phase abundances of these interstellar molecules. Interstellar hydrogen bonding may cause lower gas abundance of the complex organic molecules (COMs) at the low temperature. From these results, ketenes whose less stable isomers that are more strongly bonded to the surface of the interstellar dust grains have been observed are proposed as suitable candidates for astronomical observations.

  17. Hydrogen gas getters: Susceptibility to poisoning

    International Nuclear Information System (INIS)

    Mroz, E.J.; Dye, R.C.; Duke, J.R.; Weinrach, J.

    1998-01-01

    About 40% (∼9,000) of the ∼23,000 transuranic (TRU) waste drums at Los Alamos National Laboratory (LANL) are presently unshippable because conservative calculations suggest that the hydrogen concentration may exceed the lower explosive limit for hydrogen. This situation extends across nearly all DOE sites holding and generating TRU waste. The incorporation of a hydrogen getter such as DEB into the waste drums (or the TRUPACT II shipping containers) could substantially mitigate the explosion risk. The result would be to increase the number of drums that qualify for transportation to the Waste Isolation Pilot Plant (WIPP) without having to resort to expensive re-packaging or waste treatment technologies. However, before this approach can be implemented, key technical questions must be answered. Foremost among these is the question of whether the presence of other chemical vapors and gases in the drum might poison the catalytic reaction between hydrogen and DEB. This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to obtain fundamental information on the chemical mechanism of the catalytic reaction of hydrogen with one commonly used hydrogen getter, DEB. Experiments with these materials showed that the method of exposure affects the nature of the reaction products. The results of this work contributed to the development of a mechanistic model of the reaction

  18. Enhanced thermophilic fermentative hydrogen production from cassava stillage by chemical pretreatments

    DEFF Research Database (Denmark)

    Wang, Wen; Luo, Gang; Xie, Li

    2013-01-01

    Acid and alkaline pretreatments for enhanced hydrogen production from cassava stillage were investigated in the present study. The result showed that acid pretreatment was suitable for enhancement of soluble carbohydrate while alkaline pretreatment stimulated more soluble total organic carbon...... that the increase of all factors increased the soluble carbohydrate production, whereas hydrogen production was inhibited when the factors exceeded their optimal values. The optimal conditions for hydrogen production were pretreatment temperature 89.5 °C, concentration 1.4% and time 69 min for the highest hydrogen...

  19. Geometrical criteria versus quantum chemical criteria for assessment of intramolecular hydrogen bond (IMHB) interaction: A computational comparison into the effect of chlorine substitution on IMHB of salicylic acid in its lowest energy ground state conformer

    Energy Technology Data Exchange (ETDEWEB)

    Paul, Bijan Kumar [Department of Chemistry, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India); Guchhait, Nikhil, E-mail: nikhil.guchhait@rediffmail.com [Department of Chemistry, University of Calcutta, 92 A.P.C. Road, Calcutta 700009 (India)

    2013-02-01

    Highlights: ► Intramolecular hydrogen bonding (IMHB) in salicylic acid and its chloro derivatives. ► A complex effect of +R and −I effect of chlorine substituents on IMHB energy. ► Interplay between IMHB energy and aromaticity. ► Directional nature of IMHB from quantum chemical assessment. ► Quantum chemical treatment vs. geometrical criteria to assess weak interaction. - Abstract: Density functional theory based computational study has been performed to characterize intramolecular hydrogen bonding (IMHB) interaction in a series of salicylic acid derivatives varying in chlorine substitution on the benzene ring. The molecular systems studied are salicylic acid, 5-chlorosalicylic acid, 3,5-dichlorosalicylic acid and 3,5,6-tricholorosalicylic acid. Major emphasis is rendered on the analysis of IMHB interaction by calculation of electron density ρ(r) and Laplacian ∇{sup 2}ρ(r) at the bond critical point using atoms-in-molecule theory. Topological features, energy densities based on ρ(r) through perturbing the intramolecular H-bond distances suggest that at equilibrium geometry the IMHB interaction develops certain characteristics typical of covalent interaction. The interplay between aromaticity and resonance-assisted hydrogen bonding (RAHB) is discussed using both geometrical and magnetic criteria as the descriptors of aromaticity. The optimized geometry features, molecular electrostatic potential map analysis are also found to produce a consensus view in relation with the formation of RAHB in these systems.

  20. Geometrical criteria versus quantum chemical criteria for assessment of intramolecular hydrogen bond (IMHB) interaction: A computational comparison into the effect of chlorine substitution on IMHB of salicylic acid in its lowest energy ground state conformer

    International Nuclear Information System (INIS)

    Paul, Bijan Kumar; Guchhait, Nikhil

    2013-01-01

    Highlights: ► Intramolecular hydrogen bonding (IMHB) in salicylic acid and its chloro derivatives. ► A complex effect of +R and −I effect of chlorine substituents on IMHB energy. ► Interplay between IMHB energy and aromaticity. ► Directional nature of IMHB from quantum chemical assessment. ► Quantum chemical treatment vs. geometrical criteria to assess weak interaction. - Abstract: Density functional theory based computational study has been performed to characterize intramolecular hydrogen bonding (IMHB) interaction in a series of salicylic acid derivatives varying in chlorine substitution on the benzene ring. The molecular systems studied are salicylic acid, 5-chlorosalicylic acid, 3,5-dichlorosalicylic acid and 3,5,6-tricholorosalicylic acid. Major emphasis is rendered on the analysis of IMHB interaction by calculation of electron density ρ(r) and Laplacian ∇ 2 ρ(r) at the bond critical point using atoms-in-molecule theory. Topological features, energy densities based on ρ(r) through perturbing the intramolecular H-bond distances suggest that at equilibrium geometry the IMHB interaction develops certain characteristics typical of covalent interaction. The interplay between aromaticity and resonance-assisted hydrogen bonding (RAHB) is discussed using both geometrical and magnetic criteria as the descriptors of aromaticity. The optimized geometry features, molecular electrostatic potential map analysis are also found to produce a consensus view in relation with the formation of RAHB in these systems

  1. Deuterium isotope effects on 13C and 15N chemical shifts of intramolecularly hydrogen-bonded enaminocarbonyl derivatives of Meldrum’s and Tetronic acid

    Science.gov (United States)

    Ullah, Saif; Zhang, Wei; Hansen, Poul Erik

    2010-07-01

    Secondary deuterium isotope effects on 13C and 15N nuclear shieldings in a series of cyclic enamino-diesters and enamino-esters and acyclic enaminones and enamino-esters have been examined and analysed using NMR and DFT (B3LYP/6-31G(d,p)) methods. One-dimensional and two-dimensional NMR spectra of enaminocarbonyl and their deuterated analogues were recorded in CDCl 3 and CD 2Cl 2 at variable temperatures and assigned. 1JNH coupling constants for the derivatives of Meldrum's and tetronic acids reveal that they exist at the NH-form. It was demonstrated that deuterium isotope effects, for the hydrogen bonded compounds, due to the deuterium substitution at the nitrogen nucleus lead to large one-bond isotope effects at nitrogen, 1Δ 15N(D), and two-bond isotope effects on carbon nuclei, 2ΔC(ND), respectively. A linear correlations exist between 2ΔC(ND) and 1Δ 15N(D) whereas the correlation with δNH is divided into two. A good agreement between the experimentally observed 2ΔC(ND) and calculated dσ 13C/dR NH was obtained. A very good correlation between calculated NH bond lengths and observed NH chemical shifts is found. The observed isotope effects are shown to depend strongly on Resonance Assisted Hydrogen bonding.

  2. Nippon oil's activities toward realization of hydrogen society

    Energy Technology Data Exchange (ETDEWEB)

    Nakagawa, Kojiro; Okazaki, Junji; Kobori, Yoshihiro; Iki, Hideshi [Nippon Oil Corporation (Japan)

    2010-07-01

    Nippon Oil Corporation, a major Japanese energy distributor, has been devoting extensive efforts toward the establishment of hydrogen supply systems. The Council on Competitiveness-Nippon (COCN), an advisory organization which has influence on Japanese government policy, has announced that the establishment of hydrogen infrastructure should be started in 2015. By that time, we plan to have completed the development of necessary technologies for the infrastructure. It is well recognized that the storage and transportation of hydrogen is the sticking point on the path to realization of a hydrogen economy. The scope of our research covers key technologies for hydrogen storage and transportation, including carbon fiber reinforced plastic (CFRP) tanks for compressed hydrogen gas, hydrogen storage materials, and hydrogen transportation systems which utilize organic chemical hydride (OCH). This article describes Nippon Oil's strategy for realization of the hydrogen economy. (orig.)

  3. Process/Equipment Co-Simulation on Syngas Chemical Looping Process

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Liang; Zhou, Qiang; Fan, Liang-Shih

    2012-09-30

    The chemical looping strategy for fossil energy applications promises to achieve an efficient energy conversion system for electricity, liquid fuels, hydrogen and/or chemicals generation, while economically separate CO{sub 2} by looping reaction design in the process. Chemical looping particle performance, looping reactor engineering, and process design and applications are the key drivers to the success of chemical looping process development. In order to better understand and further scale up the chemical looping process, issues such as cost, time, measurement, safety, and other uncertainties need to be examined. To address these uncertainties, advanced reaction/reactor modeling and process simulation are highly desired and the modeling efforts can accelerate the chemical looping technology development, reduce the pilot-scale facility design time and operating campaigns, as well as reduce the cost and technical risks. The purpose of this work is thus to conduct multiscale modeling and simulations on the key aspects of chemical looping technology, including particle reaction kinetics, reactor design and operation, and process synthesis and optimization.

  4. Post-synthesis amine borane functionalization of metal-organic framework and its unusual chemical hydrogen release phenomenon

    KAUST Repository

    Berke, Heinz

    2017-05-11

    We report a novel strategy for post-synthesis amine borane functionalization of MOFs under gas-solid phase transformation utilizing gaseous diborane. The covalently confined amine borane derivative decorated on the framework backbone is stable when preserved at low temperature, but spontaneously liberates soft chemical hydrogen at room temperature leading to the development of an unusual borenium type species (-NH=BH2+) ion-paired with hydroborate anion. Furthermore, the unsaturated amino borane (-NH=BH2) and the -iminodiborane ((--NHB2H5) were detected as final products. A combination of DFT based molecular dynamics simulations and solid state NMR spectroscopy, utilizing isotopically enriched materials, were undertaken to unequivocally elucidate the mechanistic pathways for H2 liberation.

  5. Boron-nitrogen based hydrides and reactive composites for hydrogen storage

    DEFF Research Database (Denmark)

    Jepsen, Lars H.; Ley, Morten B.; Lee, Young-Su

    2014-01-01

    Hydrogen forms chemical compounds with most other elements and forms a variety of different chemical bonds. This fascinating chemistry of hydrogen has continuously provided new materials and composites with new prospects for rational design and the tailoring of properties. This review highlights...... a range of new boron and nitrogen based hydrides and illustrates how hydrogen release and uptake properties can be improved. © 2014 Elsevier Ltd....

  6. Report on surveys and researches at the New Energy General Development Organization in fiscal 1980. Surveys and researches on hydrogen energy; 1980 nendo suiso energy ni kansuru chosa kenkyu hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-09-01

    This paper describes surveys and researches on hydrogen energy in fiscal 1980. The high-temperature high-pressure water decomposition process in hydrogen manufacturing technologies had development proceeded on membranes and electrodes, and succeeded operating a 4 Nm{sup 3}/hr plant. Also for the solid electrolyte electrolytic process, a test plant of 1.3 m{sup 3}/hr was completed. The paper describes iodine and bromine system cycle, high-temperature gas atomic reactor cycle, and hybrid process with regard to the thermo-chemical method cycle. Problems in different cycles include necessities to advance the development paying attention on sufficient discussions on thermal efficiency of 35% or higher, heat regeneration and recovery, discussions on separation and transportation, and durability of reactive device materials. The paper also introduces research on hydrogen manufacturing utilizing chemical conversion of solar energy, biomass, and microorganisms. For technologies to store and transport hydrogen, the paper introduces metal hydrides, whereas Ti-based and misch metal-based alloys were found suitable. For transportation, Mg-based alloy hydrides were regarded as the most expected hydrogen absorbing material. Surveys were made also on the current status of the manufacturing industry, production and utilization of hydrogen. (NEDO)

  7. Hydrogen Bonds and Life in the Universe

    Directory of Open Access Journals (Sweden)

    Giovanni Vladilo

    2018-01-01

    Full Text Available The scientific community is allocating more and more resources to space missions and astronomical observations dedicated to the search for life beyond Earth. This experimental endeavor needs to be backed by a theoretical framework aimed at defining universal criteria for the existence of life. With this aim in mind, we have explored which chemical and physical properties should be expected for life possibly different from the terrestrial one, but similarly sustained by genetic and catalytic molecules. We show that functional molecules performing genetic and catalytic tasks must feature a hierarchy of chemical interactions operating in distinct energy bands. Of all known chemical bonds and forces, only hydrogen bonds are able to mediate the directional interactions of lower energy that are needed for the operation of genetic and catalytic tasks. For this reason and because of the unique quantum properties of hydrogen bonding, the functional molecules involved in life processes are predicted to have extensive hydrogen-bonding capabilities. A molecular medium generating a hydrogen-bond network is probably essential to support the activity of the functional molecules. These hydrogen-bond requirements constrain the viability of hypothetical biochemistries alternative to the terrestrial one, provide thermal limits to life molecular processes, and offer a conceptual framework to define a transition from a “covalent-bond stage” to a “hydrogen-bond stage” in prebiotic chemistry.

  8. Hydrogen Bonds and Life in the Universe

    Science.gov (United States)

    2018-01-01

    The scientific community is allocating more and more resources to space missions and astronomical observations dedicated to the search for life beyond Earth. This experimental endeavor needs to be backed by a theoretical framework aimed at defining universal criteria for the existence of life. With this aim in mind, we have explored which chemical and physical properties should be expected for life possibly different from the terrestrial one, but similarly sustained by genetic and catalytic molecules. We show that functional molecules performing genetic and catalytic tasks must feature a hierarchy of chemical interactions operating in distinct energy bands. Of all known chemical bonds and forces, only hydrogen bonds are able to mediate the directional interactions of lower energy that are needed for the operation of genetic and catalytic tasks. For this reason and because of the unique quantum properties of hydrogen bonding, the functional molecules involved in life processes are predicted to have extensive hydrogen-bonding capabilities. A molecular medium generating a hydrogen-bond network is probably essential to support the activity of the functional molecules. These hydrogen-bond requirements constrain the viability of hypothetical biochemistries alternative to the terrestrial one, provide thermal limits to life molecular processes, and offer a conceptual framework to define a transition from a “covalent-bond stage” to a “hydrogen-bond stage” in prebiotic chemistry. PMID:29301382

  9. Hydrogen Bonds and Life in the Universe.

    Science.gov (United States)

    Vladilo, Giovanni; Hassanali, Ali

    2018-01-03

    The scientific community is allocating more and more resources to space missions and astronomical observations dedicated to the search for life beyond Earth. This experimental endeavor needs to be backed by a theoretical framework aimed at defining universal criteria for the existence of life. With this aim in mind, we have explored which chemical and physical properties should be expected for life possibly different from the terrestrial one, but similarly sustained by genetic and catalytic molecules. We show that functional molecules performing genetic and catalytic tasks must feature a hierarchy of chemical interactions operating in distinct energy bands. Of all known chemical bonds and forces, only hydrogen bonds are able to mediate the directional interactions of lower energy that are needed for the operation of genetic and catalytic tasks. For this reason and because of the unique quantum properties of hydrogen bonding, the functional molecules involved in life processes are predicted to have extensive hydrogen-bonding capabilities. A molecular medium generating a hydrogen-bond network is probably essential to support the activity of the functional molecules. These hydrogen-bond requirements constrain the viability of hypothetical biochemistries alternative to the terrestrial one, provide thermal limits to life molecular processes, and offer a conceptual framework to define a transition from a "covalent-bond stage" to a "hydrogen-bond stage" in prebiotic chemistry.

  10. Mechanisms of Furfural Reduction on Metal Electrodes: Distinguishing Pathways for Selective Hydrogenation of Bioderived Oxygenates

    International Nuclear Information System (INIS)

    Chadderdon, Xiaotong H.; Chadderdon, David J.; Matthiesen, John E.

    2017-01-01

    Electrochemical reduction of biomass-derived platform molecules is an emerging route for the sustainable production of fuels and chemicals. Understanding gaps between reaction conditions, underlying mechanisms, and product selectivity have limited the rational design of active, stable, and selective catalyst systems. Here, the mechanisms of electrochemical reduction of furfural, an important biobased platform molecule and model for aldehyde reduction, are explored through a combination of voltammetry, preparative electrolysis, thiol-electrode modifications, and kinetic isotope studies. It is demonstrated that two distinct mechanisms are operable on metallic Cu electrodes in acidic electrolytes: (i) electrocatalytic hydrogenation (ECH) and (ii) direct electroreduction. The contributions of each mechanism to the observed product distribution are clarified by evaluating the requirement for direct chemical interactions with the electrode surface and the role of adsorbed hydrogen. Further analysis reveals that hydrogenation and hydrogenolysis products are generated by parallel ECH pathways. By understanding the underlying mechanisms it enables the manipulation of furfural reduction by rationally tuning the electrode potential, electrolyte pH, and furfural concentration to promote selective formation of important biobased polymer precursors and fuels.

  11. Mechanisms of Furfural Reduction on Metal Electrodes: Distinguishing Pathways for Selective Hydrogenation of Bioderived Oxygenates.

    Science.gov (United States)

    Chadderdon, Xiaotong H; Chadderdon, David J; Matthiesen, John E; Qiu, Yang; Carraher, Jack M; Tessonnier, Jean-Philippe; Li, Wenzhen

    2017-10-11

    Electrochemical reduction of biomass-derived platform molecules is an emerging route for the sustainable production of fuels and chemicals. However, understanding gaps between reaction conditions, underlying mechanisms, and product selectivity have limited the rational design of active, stable, and selective catalyst systems. In this work, the mechanisms of electrochemical reduction of furfural, an important biobased platform molecule and model for aldehyde reduction, are explored through a combination of voltammetry, preparative electrolysis, thiol-electrode modifications, and kinetic isotope studies. It is demonstrated that two distinct mechanisms are operable on metallic Cu electrodes in acidic electrolytes: (i) electrocatalytic hydrogenation (ECH) and (ii) direct electroreduction. The contributions of each mechanism to the observed product distribution are clarified by evaluating the requirement for direct chemical interactions with the electrode surface and the role of adsorbed hydrogen. Further analysis reveals that hydrogenation and hydrogenolysis products are generated by parallel ECH pathways. Understanding the underlying mechanisms enables the manipulation of furfural reduction by rationally tuning the electrode potential, electrolyte pH, and furfural concentration to promote selective formation of important biobased polymer precursors and fuels.

  12. Identification of chemical warfare agent with radiological measurements

    International Nuclear Information System (INIS)

    Liu Boxue; Li Yun; Ai Xianyun

    2000-01-01

    There are three non-destructive radiological methods for identification of warfare agents and TNT. Their principles and problems related were discussed. Portable isotopic neutron spectroscopy is based on the assay of key elemental composition (such as Cl, P, H, As, S, N) in chemical agents by neutron induced prompt gamma ray analysis. Hydrogen concentration measurement by means of using thermal neutron can be employed to identify chemical warfare agents and TNT that contains different hydrogen fraction. The calibration curves of thermal neutron count rate against hydrogen concentration were measured. X ray imagination system can be used to determine the internal structure of chemical bombs, there by to identify them. The radiological methods are very useful for identification of old chemical weapons abandoned by Japan Army during World War 2

  13. The AGILE on-board Kalman filter

    International Nuclear Information System (INIS)

    Giuliani, A.; Cocco, V.; Mereghetti, S.; Pittori, C.; Tavani, M.

    2006-01-01

    On-board reduction of particle background is one of the main challenges of space instruments dedicated to gamma-ray astrophysics. We present in this paper a discussion of the method and main simulation results of the on-board background filter of the Gamma-Ray Imaging Detector (GRID) of the AGILE mission. The GRID is capable of detecting and imaging with optimal point spread function gamma-ray photons in the range 30MeV-30GeV. The AGILE planned orbit is equatorial, with an altitude of 550km. This is an optimal orbit from the point of view of the expected particle background. For this orbit, electrons and positrons of kinetic energies between 20MeV and hundreds of MeV dominate the particle background, with significant contributions from high-energy (primary) and low-energy protons, and gamma-ray albedo-photons. We present here the main results obtained by extensive simulations of the on-board AGILE-GRID particle/photon background rejection algorithms based on a special application of Kalman filter techniques. This filter is applied (Level-2) sequentially after other data processing techniques characterizing the Level-1 processing. We show that, in conjunction with the Level-1 processing, the adopted Kalman filtering is expected to reduce the total particle/albedo-photon background rate to a value (=<10-30Hz) that is compatible with the AGILE telemetry. The AGILE on-board Kalman filter is also effective in reducing the Earth-albedo-photon background rate, and therefore contributes to substantially increase the AGILE exposure for celestial gamma-ray sources

  14. Carbon-supported cobalt catalyst for hydrogen generation from alkaline sodium borohydride solution

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Dongyan; Liu, Xinmin; Cao, Changqing; Guo, Qingjie [College of Chemical Engineering, Qingdao University of Science and Technology, Qingdao 266042 (China); Dai, Ping [College of Electromechanical Engineering, Qingdao University of Science and Technology, Qingdao 266061 (China)

    2008-08-01

    Low cost transition metal catalysts with high performance are attractive for the development of on-board hydrogen generation systems by catalytic hydrolysis of sodium borohydride (NaBH{sub 4}) in fuel cell fields. In this study, hydrogen production from alkaline NaBH{sub 4} via hydrolysis process over carbon-supported cobalt catalysts was studied. The catalytic activity of the supported cobalt catalyst was found to be highly dependent on the calcination temperatures. The hydrogen generation rate increases with calcination temperatures in the range of 200-400 C, but a high calcination temperature above 500 C led to markedly decreased activity. X-ray diffraction patterns reveal that the catalysts experience phase transition from amorphous Co-B to crystalline cobalt hydroxide with increase in calcination temperatures. The reaction performance is also dependent on the concentration of NaBH{sub 4}, and the hydrogen generation rate increases for lower NaBH{sub 4} concentrations and decreases after reaching a maximum at 10 wt.% of NaBH{sub 4}. (author)

  15. 700 bar hydrogen cylinder design, testing and certification

    International Nuclear Information System (INIS)

    Duncan, M.

    2004-01-01

    'Full text:' Light weight and high pressure cylinders for compressed hydrogen storage are essential components for fuel cell vehicles. Storage volume and mass are two key considerations. Current on-board hydrogen storage systems are based on a maximum pressure of 350 bar. While 350 bar systems are excellent solutions for many applications, some situations required higher storage densities due to space restrictions. As a result significant research and development work has been expended by cylinder manufacturers, systems providers, testing agencies and automotive manufacturers to develop 700 bar systems to reduce storage volume. Dynetek Industries Ltd has proactively developed a range of 700 bar storage cylinders based on a seamless aluminum liner over wrapped with a carbon fiber composite. This paper presents the challenges and processes involved in the design, testing and certification of the Dynetek Industries Ltd 700 bar cylinder. The paper also provides reasoning for further volume and mass optimization of compressed hydrogen cylinders by incorporating realistic cylinder usage parameters into standards. In particular the overly conservative fill life requirement for cylinders will be examined. (author)

  16. Board members’ contribution to strategy: The mediating role of board internal processes

    Directory of Open Access Journals (Sweden)

    Carmen Barroso-Castro

    2017-05-01

    Full Text Available This study aims to explore what directors do on the board, to what extent the processes occurring in the board allow the sharing and integrating of the existing knowledge, thus facilitating the board members’ contributions to strategy. We adopt the view that the internal board processes increase the impact of the cognitive resources on board performance. Using survey data from 200 large Spanish companies we demonstrate that directors’ level of knowledge of the firm and board job-related diversity positively influence the degree of the board's strategic involvement. Additionally, the internal processes that take place within the board – particularly Cognitive Conflict, the Critical and Independent Approach and the Comprehensive Discussion Process – influence the board's strategic involvement and play a partial mediating role on the aforementioned relationships. However, our results show no evidence for a positive relationship between Board Meeting Dynamics and the board's strategic involvement.

  17. Specialty Board on Fluency Disorders

    Science.gov (United States)

    ... or large groups of speech-language pathologists. Speech-language pathologists who are Board Certified Specialists in Fluency may be found on this website by searching name, city(location) or zip code. ...

  18. USE OF THE MODULAR HELIUM REACTOR FOR HYDROGEN PRODUCTION

    International Nuclear Information System (INIS)

    SCHULTZ, K.R.

    2003-01-01

    OAK-B135 A significant ''Hydrogen Economy'' is predicted that will reduce our dependence on petroleum imports and reduce pollution and greenhouse gas emissions. Hydrogen is an environmentally attractive fuel that has the potential to displace fossil fuels, but contemporary hydrogen production is primarily based on fossil fuels. The author has recently completed a three-year project for the US Department of Energy (DOE) whose objective was to ''define an economically feasible concept for production of hydrogen, using an advanced high-temperature nuclear reactor as the energy source''. Thermochemical water-slitting, a chemical process that accomplishes the decomposition of water into hydrogen and oxygen, met this objective. The goal of the first phase of this study was to evaluate thermochemical processes which offer the potential for efficient, cost-effective, large-scale production of hydrogen, and to select one for further detailed consideration. They selected the Sulfur-Iodine cycle. In the second phase, they reviewed all the basic reactor types for suitability to provide the high temperature heat needed by the selected thermochemical water splitting cycle and chose the helium gas-cooled reactor. In the third phase they designed the chemical flowsheet for the thermochemical process and estimated the efficiency and cost of the process and the projected cost of producing hydrogen. These results are summarized in this report

  19. Matrix effect on hydrogen-atom tunneling of organic molecules in cryogenic solids

    International Nuclear Information System (INIS)

    Ichikawa, Tsuneki

    2000-01-01

    Although the tunneling of atoms through potential energy barriers separating the reactant and reaction systems is not paid much attention in organic reactions, this plays an important role in reactions including the transfer of light atoms. Atomic tunneling is especially important for chemical reactions at low temperatures, since the thermal activation of reactant systems is very slow process in comparison with the tunneling. One of the typical reactions of atomic tunneling is hydrogen-atom abstraction from alkanes in cryogenic solids exposed to high-energy radiation. Irradiation of alkane molecules causes the homolytic cleavage of C-H bonds, which results in the pairwise formation of free hydrogen atoms and organic free radicals. Since the activation energies for the abstraction of hydrogen atoms from alkane molecules by free hydrogen atoms are higher than 5 kcal/mol, the lifetime of free hydrogen atoms at 77 K is estimated from the Arrhenius equation of k=vexp(-E a /RT) to be longer than 10 hrs. However, except for solid methane, free hydrogen atoms immediately convert to alkyl radicals even at 4.2 K by hydrogen-atom tunneling from alkane molecules to the free hydrogen atoms. The rate of hydrogen atom tunneling does not necessary increase with decreasing activation energy or the peak height of the potential energy barrier preventing the tunneling. Although the activation energy is the lowest at the tertiary carbon of alkanes, hydrogen atom tunneling from branched alkanes with tertiary carbon at the antepenultimate position of the carbon skeleton is the fastest at the secondary penultimate carbon. Based on our experimental results, we have proposed that the peculiarity of the hydrogen-atom abstraction in cryogenic solids comes from the steric hindrance by matrix molecules to the deformation of alkane molecules from the initial sp 3 to the final sp 2 configurations. The steric hindrance causes the increase of the height of the potential energy barrier for the

  20. Hydrogen storage using borohydrides

    International Nuclear Information System (INIS)

    Bernard BONNETOT; Laetitia LAVERSENNE

    2006-01-01

    The possibilities of hydrogen storage using borohydrides are presented and discussed specially in regard of the recoverable hydrogen amount and related to the recovering conditions. A rapid analysis of storage possibilities is proposed taking in account the two main ways for hydrogen evolution: the dehydrogenation obtained through thermal decomposition or the hydrolysis of solids or solutions. The recoverable hydrogen is related to the dehydrogenation conditions and the real hydrogen useful percentage is determined for each case of use. The high temperature required for dehydrogenation even when using catalyzed compounds lead to poor outlooks for this storage way. The hydrolysis conditions direct the chemical yield of the water consuming, and this must be related to the experimental conditions which rule the storage capacity of the 'fuel' derived from the borohydride. (authors)

  1. Support screening studies on the hydrogenation of levulinic acid to γ‐valerolactone in water using RU catalysts

    NARCIS (Netherlands)

    Piskun, Anna; Winkelman, Jozef G M; Tang, Zhenchen; Heeres, Hero Jan

    2016-01-01

    γ-Valerolactone (GVL) has been identified as a sustainable platform chemical for the production of carbon-based chemicals. Here we report a screening study on the hydrogenation of levulinic acid (LA) to GVL in water using a wide range of ruthenium supported catalysts in a batch set-up (1 wt. % Ru,

  2. A study on hydrogen-storage behaviors of nickel-loaded mesoporous MCM-41.

    Science.gov (United States)

    Park, Soo-Jin; Lee, Seul-Yi

    2010-06-01

    The objective of the present work was to investigate the possibility of improving the hydrogen-storage capacity of mesoporous MCM-41 containing nickel (Ni) oxides (Ni/MCM-41). The MCM-41 and Ni/MCM-41 were prepared using a hydrothermal process as a function of Ni content (2, 5, and 10 wt.% in the MCM-41). The surface functional groups of the Ni/MCM-41 were identified by Fourier transform infrared spectroscopy (FTIR). The structure and morphology of the Ni/MCM-41 were characterized by X-ray diffraction (XRD) and field emission transmission electron microscopy (FE-TEM). XRD results showed a well-ordered hexagonal pore structure; FE-TEM also revealed, as a complementary technique, the structure and pore size. The textural properties of the Ni/MCM-41 were analyzed using N(2) adsorption isotherms at 77 K. The hydrogen-storage capacity of the Ni/MCM-41 was evaluated at 298 K/100 bar. It was found that the presence of Ni on mesoporous MCM-41 created hydrogen-favorable sites that enhanced the hydrogen-storage capacity by a spillover effect. Furthermore, it was concluded that the hydrogen-storage capacity was greatly influenced by the amount of nickel oxide, resulting in a chemical reaction between Ni/MCM-41 and hydrogen molecules. Crown Copyright © 2010. Published by Elsevier Inc. All rights reserved.

  3. Production of hydrogen, liquid fuels, and chemicals from catalytic processing of bio-oils

    Science.gov (United States)

    Huber, George W; Vispute, Tushar P; Routray, Kamalakanta

    2014-06-03

    Disclosed herein is a method of generating hydrogen from a bio-oil, comprising hydrogenating a water-soluble fraction of the bio-oil with hydrogen in the presence of a hydrogenation catalyst, and reforming the water-soluble fraction by aqueous-phase reforming in the presence of a reforming catalyst, wherein hydrogen is generated by the reforming, and the amount of hydrogen generated is greater than that consumed by the hydrogenating. The method can further comprise hydrocracking or hydrotreating a lignin fraction of the bio-oil with hydrogen in the presence of a hydrocracking catalyst wherein the lignin fraction of bio-oil is obtained as a water-insoluble fraction from aqueous extraction of bio-oil. The hydrogen used in the hydrogenating and in the hydrocracking or hydrotreating can be generated by reforming the water-soluble fraction of bio-oil.

  4. The Effect of Converting to a U.S. Hydrogen Fuel Cell Vehicle Fleet on Emissions and Energy Use

    Science.gov (United States)

    Colella, W. G.; Jacobson, M. Z.; Golden, D. M.

    2004-12-01

    This study analyzes the potential change in emissions and energy use from replacing fossil-fuel based vehicles with hydrogen fuel cell vehicles. This study examines three different hydrogen production scenarios to determine their resultant emissions and energy usage: hydrogen produced via 1) steam reforming of methane, 2) coal gasification, or 3) wind electrolysis. The atmospheric model simulations require two primary sets of data: the actual emissions associated with hydrogen fuel production and use, and the corresponding reduction in emissions associated with reducing fossil fuel use. The net change in emissions is derived using 1) the U.S. EPA's National Emission Inventory (NEI) that incorporates several hundred categories of on-road vehicles and 2) a Process Chain Analysis (PCA) for the different hydrogen production scenarios. NEI: The quantity of hydrogen-related emission is ultimately a function of the projected hydrogen consumption in on-road vehicles. Data for hydrogen consumption from on-road vehicles was derived from the number of miles driven in each U.S. county based on 1999 NEI data, the average fleet mileage of all on-road vehicles, the average gasoline vehicle efficiency, and the efficiency of advanced 2004 fuel cell vehicles. PCA: PCA involves energy and mass balance calculations around the fuel extraction, production, transport, storage, and delivery processes. PCA was used to examine three different hydrogen production scenarios: In the first scenario, hydrogen is derived from natural gas, which is extracted from gas fields, stored, chemically processed, and transmitted through pipelines to distributed fuel processing units. The fuel processing units, situated in similar locations as gasoline refueling stations, convert natural gas to hydrogen via a combination of steam reforming and fuel oxidation. Purified hydrogen is compressed for use onboard fuel cell vehicles. In the second scenario, hydrogen is derived from coal, which is extracted from

  5. Hydrogen Atom Collision Processes in Cool Stellar Atmospheres: Effects on Spectral Line Strengths and Measured Chemical Abundances in Old Stars

    International Nuclear Information System (INIS)

    Barklem, Paul S

    2012-01-01

    The precise measurement of the chemical composition of stars is a fundamental problem relevant to many areas of astrophysics. State-of-the-art approaches attempt to unite accurate descriptions of microphysics, non-local thermodynamic equilibrium (non-LTE) line formation and 3D hydrodynamical model atmospheres. In this paper I review progress in understanding inelastic collisions of hydrogen atoms with other species and their influence on spectral line formation and derived abundances in stellar atmospheres. These collisions are a major source of uncertainty in non-LTE modelling of spectral lines and abundance determinations, especially for old, metal-poor stars, which are unique tracers of the early evolution of our galaxy. Full quantum scattering calculations of direct excitation processes X(nl) + H ↔ X(n'l') + H and charge transfer processes X(nl) + H ↔ X + + H − have been done for Li, Na and Mg [1,2,3] based on detailed quantum chemical data, e.g. [4]. Rate coefficients have been calculated and applied to non-LTE modelling of spectral lines in stellar atmospheres [5,6,7,8,9]. In all cases we find that charge transfer processes from the first excited S-state are very important, and the processes affect measured abundances for Li, Na and Mg in some stars by as much as 60%. Effects vary with stellar parameters (e.g. temperature, luminosity, metal content) and so these processes are important not only for accurate absolute abundances, but also for relative abundances among dissimilar stars.

  6. Evaluation of hydrogen demonstration systems (Task 18 of IEA Implementing Agreement on Hydrogen)

    Energy Technology Data Exchange (ETDEWEB)

    Baker, J N; Carter, S

    2005-07-01

    Task 18 aims to gather information about the integration of hydrogen into society around the world. As part of subtask B (demonstration projects), EA Technology Limited collected information and data on specific UK hydrogen demonstration projects and case studies. The work involved desk research, a literature review, telephone conversations and meetings with developers and operators of hydrogen-related projects in the UK. Various examples were identified in phase 1 that were either proposed, planned, under construction, commissioned or operational. The main demonstration activities described in the report are: the Clean Urban Transport for Europe (CUTE) refuelling station at Hornchurch in Essex; the Hydrogen and Renewables Integration (HARI) project at West Beacon Farm, Leicestershire; the Promoting Unst Renewable Energy (PURE) project on Unst in the Shetland Isles; the Hunterston Hydrogen Project in North Ayrshire, Scotland; and the Tees Valley Hydrogen Project. The CUTE, HARI and PURE projects were selected for inclusion in the overall Task 18 workplan. The report also covers developments associated with the Fuel Cell House, the Hydrogen Office, INEOS Chlor, the London Hydrogen Partnership and the Wales Hydrogen Project.

  7. Summary of achievement reports on the Sunshine Project in fiscal 1978 (Hydrogen energy); 1978 nendo seika hokokusho gaiyoshu. Suiso energy

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-04-01

    This paper summarizes achievement reports on the Sunshine Project in fiscal 1978 (hydrogen energy). In hydrogen manufacturing methods, studies are described on materials of membranes and electrodes used in high temperature and pressure electrolysis. In thermo-chemical method, studies are continuing on cycles of the iron system, iodine system, and mixed system (composed by thermal, photo and electro-chemistries). For the iodine system, summary design was performed on an experimental device. For the mixed system, trial fabrication and experiments were carried out on a beam radiation type electrolytic tank that electrolyses quickly HI and Fe{sup 3+} produced in the photo-chemical reaction, and separates the products. Discussions were also given on HI decomposition (hydrogen acquisition) by means of heat diffusion. With respect to storage and transportation, development is being made on optimal metal hydrides. In combustion technologies, discussions are given on combustors and catalysts to break through the dilemma of high NOx emission and frequent occurrence of reverse ignition. For fuel cells, the paper describes developments of the materials thereof, high-temperature solid electrolyte type fuel cells and alkaline aqueous solution electrolyte type fuel cells. Regarding the non-steady hydrogen engines, the paper describes fundamental studies on non-steady jet flow behavior using shock tubes, and single cylinder engine tests. It also describes hydrogen safety assuring measures, and studies on energy systems. (NEDO)

  8. Hydrogen adsorption in metal-decorated silicon carbide nanotubes

    Science.gov (United States)

    Singh, Ram Sevak; Solanki, Ankit

    2016-09-01

    Hydrogen storage for fuel cell is an active area of research and appropriate materials with excellent hydrogen adsorption properties are highly demanded. Nanotubes, having high surface to volume ratio, are promising storage materials for hydrogen. Recently, silicon carbide nanotubes have been predicted as potential materials for future hydrogen storage application, and studies in this area are ongoing. Here, we report a systematic study on hydrogen adsorption properties in metal (Pt, Ni and Al) decorated silicon carbide nanotubes (SiCNTs) using first principles calculations based on density functional theory. The hydrogen adsorption properties are investigated by calculations of adsorption energy, electronic band structure, density of states (DOS) and Mulliken charge population analysis. Our findings show that hydrogen adsorptions on Pt, Ni and Al-decorated SiCNTs undergo spontaneous exothermic reactions with significant modulation of electronic structure of SiCNTs in all cases. Importantly, according to the Mulliken charge population analysis, dipole-dipole interaction causes chemisorptions of hydrogen in Pt, Ni and Al decorated SiCNTs with formation of chemical bonds. The study is a platform for the development of metal decorated SiCNTs for hydrogen adsorption or hydrogen storage application.

  9. Electrocatalytic hydrogenation and hydrodeoxygenation of oxygenated and unsaturated organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, James E.; Lam, Chun Ho; Saffron, Christopher M.; Miller, Dennis J.

    2018-04-24

    A process and related electrode composition are disclosed for the electrocatalytic hydrogenation and/or hydrodeoxygenation of organic substrates such as biomass-derived bio-oil components by the production of hydrogen atoms on a catalyst surface followed by the reaction of the hydrogen atoms with the organic reactants. Biomass fast pyrolysis-derived bio-oil is a liquid mixture containing hundreds of organic compounds with chemical functionalities that are corrosive to container materials and are prone to polymerization. A high surface area skeletal metal catalyst material such as Raney Nickel can be used as the cathode. Electrocatalytic hydrogenation and/or hydrodeoxygenation convert the organic substrates under mild conditions to reduce coke formation and catalyst deactivation. The process converts oxygen-containing functionalities and unsaturated bonds into chemically reduced forms with an increased hydrogen content. The process is operated at mild conditions, which enables it to be a good means for stabilizing bio-oil to a form that can be stored and transported using metal containers and pipes.

  10. A hydrogen refill for cellular phone

    Science.gov (United States)

    Prosini, Pier Paolo; Gislon, Paola

    A device has been designed to generate hydrogen for a fuel cell powered cellular phone. The device is based on the chemical reaction between NaBH 4 and hydrochloric/water solution to satisfy the hydrogen request at room temperature and pressure. The operation mechanism and controlling method is based on the Kipp's gas generating apparatus. A prototype has been built and tested to evaluate the optimum salt/acid and acid/solution ratios and check the hydrogen mass flow rates upon operation and the pressure variation in stand-by condition. The system works delivering hydrogen flows ranging between 0 and 10 ml min -1. In a typical test the hydrogen flow was set to 5 ml min -1 to match a 1 W power fuel cell. The working pressure was slightly higher than the atmospheric one. The hydrogen capacity was as high as 2.5% (w/w). By converting this amount of hydrogen in electricity by a fuel cell working at 0.8 V it is possible to achieve a system energy density of about 720 Wh kg -1, four times larger than commercial high energy density lithium-ion batteries.

  11. Excess Adsorption Isotherms of Hydrogen on Activated Carbons from Agricultural Waste Materials.

    Czech Academy of Sciences Publication Activity Database

    Soukup, Karel; Hejtmánek, Vladimír; Cruz, G.J.F.; Jandová, Věra; Šolcová, Olga

    2017-01-01

    Roč. 40, č. 5 (2017), s. 900-906 ISSN 0930-7516. [International Congress of Chemical and Process Engineering CHISA 2016 and the 19th Conference PRES 2016 /22./. Prague, 27.08.2016-31.08.2016] R&D Projects: GA ČR GA15-14228S Grant - others:NUT(PE) 0722-2014/UNT-R Institutional support: RVO:67985858 Keywords : activated carbon * hydrogen * excess adsorption Subject RIV: CI - Industrial Chemistry, Chemical Engineering OBOR OECD: Chemical process engineering Impact factor: 2.051, year: 2016

  12. Solar driven technologies for hydrogen production

    Directory of Open Access Journals (Sweden)

    Medojević Milovan M.

    2016-01-01

    Full Text Available Bearing in mind that the production of hydrogen based on renewable energy sources, without doubt, is an important aspect to be taken into account when considering the potential of this gas, where as particularly interesting technologies stand out the ones which are based on the use of solar energy to produce hydrogen. The goal of this paper provides basic technological trajectories, with the possibility of combining, for solar driven hydrogen production, such as: electrochemical, photochemical and thermochemical process. Furthermore, the paper presents an analysis of those technologies from a technical as well as economic point of view. In addition, the paper aims to draw attention to the fact that the generation of hydrogen using renewable energy should be imposed as a logical and proper way to store solar energy in the form of chemical energy.

  13. First-Principles and Thermodynamic Simulation of Elastic Stress Effect on Energy of Hydrogen Dissolution in Alpha Iron

    Science.gov (United States)

    Rakitin, M. S.; Mirzoev, A. A.; Mirzaev, D. A.

    2018-04-01

    Mobile hydrogen, when dissolving in metals, redistributes due to the density gradients and elastic stresses, and enables destruction processes or phase transformations in local volumes of a solvent metal. It is rather important in solid state physics to investigate these interactions. The first-principle calculations performed in terms of the density functional theory, are used for thermodynamic simulation of the elastic stress effect on the energy of hydrogen dissolution in α-Fe crystal lattice. The paper presents investigations of the total energy of Fe-H system depending on the lattice parameter. As a result, the relation is obtained between the hydrogen dissolution energy and stress. A good agreement is shown between the existing data and simulation results. The extended equation is suggested for the chemical potential of hydrogen atom in iron within the local stress field. Two parameters affecting the hydrogen distribution are compared, namely local stress and phase transformations.

  14. Effect of Hydrogen Addition on Methane HCCI Engine Ignition Timing and Emissions Using a Multi-zone Model

    Science.gov (United States)

    Wang, Zi-han; Wang, Chun-mei; Tang, Hua-xin; Zuo, Cheng-ji; Xu, Hong-ming

    2009-06-01

    Ignition timing control is of great importance in homogeneous charge compression ignition engines. The effect of hydrogen addition on methane combustion was investigated using a CHEMKIN multi-zone model. Results show that hydrogen addition advances ignition timing and enhances peak pressure and temperature. A brief analysis of chemical kinetics of methane blending hydrogen is also performed in order to investigate the scope of its application, and the analysis suggests that OH radical plays an important role in the oxidation. Hydrogen addition increases NOx while decreasing HC and CO emissions. Exhaust gas recirculation (EGR) also advances ignition timing; however, its effects on emissions are generally the opposite. By adjusting the hydrogen addition and EGR rate, the ignition timing can be regulated with a low emission level. Investigation into zones suggests that NOx is mostly formed in core zones while HC and CO mostly originate in the crevice and the quench layer.

  15. Significance of Isotopically Labile Organic Hydrogen in Thermal Maturation of Organic Matter

    Energy Technology Data Exchange (ETDEWEB)

    Arndt Schimmelmann; Maria Mastalerz

    2010-03-30

    Isotopically labile organic hydrogen in fossil fuels occupies chemical positions that participate in isotopic exchange and in chemical reactions during thermal maturation from kerogen to bitumen, oil and gas. Carbon-bound organic hydrogen is isotopically far less exchangeable than hydrogen bound to nitrogen, oxygen, or sulfur. We explore why organic hydrogen isotope ratios express a relationship with organic nitrogen isotope ratios in kerogen at low to moderate maturity. We develop and apply new techniques to utilize organic D/H ratios in organic matter fractions and on a molecular level as tools for exploration for fossil fuels and for paleoenvironmental research. The scope of our samples includes naturally and artificially matured substrates, such as coal, shale, oil and gas.

  16. An Influence Study of Hydrogen Evolution Characteristics on the Negative Strap Corrosion of Lead Acid Battery

    Directory of Open Access Journals (Sweden)

    Zhong Guobin

    2015-01-01

    Full Text Available Negative strap corrosion is an important reason for the failure of valve regulated lead acid battery. This paper selected the Pb-Sb alloy material and Pb-Sn alloy material, made an investigation on the negative corrosion resistance and hydrogen evolution of these two alloy materials by scanning electron microscope analysis, metallographic analysis, chemical study and linear sweep voltammetry, and discussed the influence of lead alloy hydrogen evolution on the negative strap corrosion. The results showed that the hydrogen evolution reaction rates of the alloys had an impact on the corrosion areas with the maximum thickness of the alloys and the depth of corrosion layers. Greater hydrogen evolution reaction rate can lead to shorter distance between the corrosion area with the maximum thickness and the liquid level; whereas the greater corrosion layer thickness can bring aggravated risk of negative strap corrosion failure.

  17. US DOE Perspectives on Advisory Board Effectiveness - 13539

    International Nuclear Information System (INIS)

    Adler, David

    2013-01-01

    Federal missions on the Oak Ridge Reservation began with the Manhattan Project, and continues today with major facilities supporting the Nation's Science and National Security missions. While most of the land area on the Oak Ridge Reservation is free of environmental impacts from these activities, significant legacy contamination is associated with specific facilities and past waste management areas. In 1989, the Oak Ridge Reservation (ORR) was placed on National Priorities List, and DOE established its Office of Environmental Management that same year. Three years later, in 1992, the Federal Facility Agreement for the reservation was signed. Three years afterward, the Oak Ridge Site Specific Advisory Board was established to augment ongoing public involvement activities related to Oak Ridge Reservation cleanup activities. One of the early and most impactful decisions the board made was to organize the End Use Working Group. This broad-based group of board members, DOE representatives, and members of the public was formed in 1997 to study future uses for contaminated areas of the reservation. The group was instrumental in building consensus in the Oak Ridge community regarding the long-term end state of reservation lands. The group's recommendations were a fundamental input into Record's of Decision subsequently developed to establish cleanup requirements across the ORR, and they continue to influence decisions being made today. In developing its recommendations on end states, the End Use Working Group came to the realization that long-term stewardship of contaminated areas of the reservation would be necessary, in some cases in perpetuity. It was from this concept that the Oak Ridge SSAB's 15-year involvement in stewardship would begin. A stewardship committee formed by the End Use Working Group wrote Volume 1 of the Stakeholder Report on Stewardship. This document-and its companion Volume 2, which was written a year later-form a crucial foundation for stewardship

  18. US DOE Perspectives on Advisory Board Effectiveness - 13539

    Energy Technology Data Exchange (ETDEWEB)

    Adler, David [US DOE (United States)

    2013-07-01

    Federal missions on the Oak Ridge Reservation began with the Manhattan Project, and continues today with major facilities supporting the Nation's Science and National Security missions. While most of the land area on the Oak Ridge Reservation is free of environmental impacts from these activities, significant legacy contamination is associated with specific facilities and past waste management areas. In 1989, the Oak Ridge Reservation (ORR) was placed on National Priorities List, and DOE established its Office of Environmental Management that same year. Three years later, in 1992, the Federal Facility Agreement for the reservation was signed. Three years afterward, the Oak Ridge Site Specific Advisory Board was established to augment ongoing public involvement activities related to Oak Ridge Reservation cleanup activities. One of the early and most impactful decisions the board made was to organize the End Use Working Group. This broad-based group of board members, DOE representatives, and members of the public was formed in 1997 to study future uses for contaminated areas of the reservation. The group was instrumental in building consensus in the Oak Ridge community regarding the long-term end state of reservation lands. The group's recommendations were a fundamental input into Record's of Decision subsequently developed to establish cleanup requirements across the ORR, and they continue to influence decisions being made today. In developing its recommendations on end states, the End Use Working Group came to the realization that long-term stewardship of contaminated areas of the reservation would be necessary, in some cases in perpetuity. It was from this concept that the Oak Ridge SSAB's 15-year involvement in stewardship would begin. A stewardship committee formed by the End Use Working Group wrote Volume 1 of the Stakeholder Report on Stewardship. This document-and its companion Volume 2, which was written a year later-form a crucial

  19. Iron titanium manganase alloy hydrogen storage

    Science.gov (United States)

    Reilly, James J.; Wiswall, Jr., Richard H.

    1979-01-01

    A three component alloy capable of reversible sorption of hydrogen having the chemical formula TiFe.sub.1-x Mn.sub.x where x is in the range of about 0.02 to 0.5 and the method of storing hydrogen using said alloy.

  20. Hydrogen energy in changing environmental scenario: Indian context

    International Nuclear Information System (INIS)

    Leo Hudson, M. Sterlin; Dubey, P.K.; Pukazhselvan, D.; Pandey, Sunil Kumar; Singh, Rajesh Kumar; Raghubanshi, Himanshu; Shahi, Rohit R.; Srivastava, O.N.

    2009-01-01

    This paper deals with how the Hydrogen Energy may play a crucial role in taking care of the environmental scenario/climate change. The R and D efforts, at the Hydrogen Energy Center, Banaras Hindu University have been described and discussed to elucidate that hydrogen is the best option for taking care of the environmental/climate changes. All three important ingredients for hydrogen economy, i.e., production, storage and application of hydrogen have been dealt with. As regards hydrogen production, solar routes consisting of photoelectrochemical electrolysis of water have been described and discussed. Nanostructured TiO 2 films used as photoanodes have been synthesized through hydrolysis of Ti[OCH(CH 3 ) 2 ] 4 . Modular designs of TiO 2 photoelectrode-based PEC cells have been fabricated to get high hydrogen production rate (∝10.35 lh -1 m -2 ). However, hydrogen storage is a key issue in the success and realization of hydrogen technology and economy. Metal hydrides are the promising candidates due to their safety advantage with high volume efficient storage capacity for on-board applications. As regards storage, we have discussed the storage of hydrogen in intermetallics as well as lightweight complex hydride systems. For intermetallic systems, we have dealt with material tailoring of LaNi 5 through Fe substitution. The La(Ni l-x Fe x ) 5 (x = 0.16) has been found to yield a high storage capacity of ∝2.40 wt%. We have also discussed how CNT admixing helps to improve the hydrogen desorption rate of NaAlH 4 . CNT (8 mol%) admixed NaAlH 4 is found to be optimum for faster desorption (∝3.3 wt% H 2 within 2 h). From an applications point of view, we have focused on the use of hydrogen (stored in intermetallic La-Ni-Fe system) as fuel for Internal Combustion (IC) engine-based vehicular transport, particularly two and three-wheelers. It is shown that hydrogen used as a fuel is the most effective alternative fuel for circumventing climate change. (author)

  1. AGB Statement on Board Responsibility for the Oversight of Educational Quality

    Science.gov (United States)

    Association of Governing Boards of Universities and Colleges, 2011

    2011-01-01

    This "Statement on Board Responsibility for the Oversight of Educational Quality," approved by the Board of Directors of the Association of Governing Boards (AGB) in March 2011, urges institutional administrators and governing boards to engage fully in this area of board responsibility. The seven principles in this statement offer suggestions to…

  2. Electrocatalytic hydrogenation of organic molecules on conductive new catalytic material

    Energy Technology Data Exchange (ETDEWEB)

    Tountian, D. [Louis Pasteur Univ., Strasbourg (France). Laboratoire d' Electrochimie et de Chimie Physique du Corps Solide; Sherbrooke Univ., Sherbrooke, PQ (Canada). Dept. de Chimie, Centre de Recherche en Electrochimie et Electrocatalyse; Brisach-Wittmeyer, A.; Menard, H. [Sherbrooke Univ., Sherbrooke, PQ (Canada). Dept. de Chimie, Centre de Recherche en Electrochimie et Electrocatalyse; Nkeng, P.; Poillerat, G. [Louis Pasteur Univ., Strasbourg (France). Laboratoire d' Electrochimie et de Chimie Physique du Corps Solide

    2008-07-01

    Electrocatalytic hydrogenation (ECH) of organic molecules is a process where chemisorbed hydrogen is produced by electroreduction of water which reacts with the species in bulk. Greater emphasis is being placed on improving the nature of the building material of the electrodes in order to increase ECH efficiency. The effectiveness of the ECH is known to be linked to the nature of electrode materials used and their adsorption properties. This work presented the effect of conductive support material on ECH. The conductive catalysts were obtained from tin dioxide which is chemically stable. Palladium was the catalytic metal used in this study. The production of chemisorbed hydrogen was shown to depend on the quantity of metallic nanoaggregates in electrical contact with the reticulated vitreous carbon use as electrode. The conductive support, F-doped tin dioxide, was obtained by the sol-gel method. The electrocatalysts were characterized by different methods as resistivity measurements, linear sweep voltammetry, XRD, SEM, TGA/DSC, and FTIR analysis. The effects of temperature and time of calcination were also investigated. The study showed that the F-doped SnO2 electrocatalyst appeared to increase the rate of phenol electrohydrogenation. It was concluded that the improved electrocatalytic activity of Pd/F-doped SnO2 can be attributed to the simultaneous polarization of all the metallic Pd nanoaggregates present on the surface as well as in the pores of the matrix by contact with RVC. This results in a better production of chemisorbed atomic hydrogen with a large number of adlienation points. 9 refs., 3 figs.

  3. Innovative hydrogen storage in hollow glass-microspheres

    Energy Technology Data Exchange (ETDEWEB)

    Keding, M.; Schmid, G.; Tajmar, M. [Austrian Research Centers, Vienna (Austria)

    2009-07-01

    Hydrogen storage technologies are becoming increasingly important for a number of future applications. The Austrian Research Centers (ARC) are developing a unique hydrogen storage system that combines the advantages of both hollow glass microsphere and chemical compound hydrogen storage, but eliminates their respective drawbacks. Water is utilized as a functional liquid to carry the hollow glass microspheres that are loaded with up to 700 bar of hydrogen gas. Sodium borohydride (NaBH{sub 4}) is then injected together with the glass microspheres into a reaction chamber where the water reacts catalytically with the NaBH{sub 4} producing hydrogen and heat. The heat is then utilized to release the hydrogen from the hollow glass microspheres providing a double hydrogen generation process without any external energy or heat during storage or gas release. The paper described this hydrogen storage system with particular reference to microspheres, the coating process, the experimental facility and NaBH{sub 4} test results. It was concluded that hydrogen storage and production on demand is possible with microspheres and sodium borohydride solution. 9 refs., 16 figs.

  4. Network on chip master control board for neutron acquisition

    International Nuclear Information System (INIS)

    Ruiz-Martinez, E.; Mary, T.; Mutti, P.; Ratel, J.; Rey, F.

    2012-01-01

    The acquisition master control board is designed to assemble the various acquisition modes in use at the Institut Laue-Langevin (ILL). The main goal is to make the card common for all the ILL's instruments in a simple, modular and open way, giving the possibility to add new functionalities in order to follow the evolving demand. It has been necessary to define a central element to provide synchronization to the rest of the units. The backbone of the proposed acquisition control system is the denominated master acquisition board. The master board consists on a VME64X configurable high density I/O connection carrier board based on the latest Xilinx Virtex-6T FPGA. The internal architecture of the FPGA is designed as a Network on Chip (NoC) approach. The complete system also includes a display board and n histogram modules for live display of the data from the detectors. (authors)

  5. Information exchange on HTGR and nuclear hydrogen technology between JAEA and INET in 2008

    International Nuclear Information System (INIS)

    Fujimoto, Nozomu; Tachibana, Yukio; Sun Yuliang

    2009-07-01

    The worldwide interests in the HTGR (High Temperature Gas-cooled Reactor) have been growing because the high temperature heat produced by the reactor can be utilized not only for efficient power generation but also for broad process heat applications, especially for thermo-chemical hydrogen production to fuel a prospective hydrogen economy in future. Presently only two HTGR reactors are operational in the world, including the HTTR (High Temperature Engineering Test Reactor) in Japan Atomic Energy Agency (JAEA) and the HTR-10 in the Institute of Nuclear and New Energy Technology (INET) of Tsinghua University in China. JAEA and INET have cooperated since 1986 in the field of HTGR development, particularly on the HTTR and HTR-10 projects. This report describes the cooperation activities on HTGR and nuclear hydrogen technology between JAEA and INET in 2008. (author)

  6. Information exchange on HTGR and nuclear hydrogen technology between JAEA and INET in 2009

    International Nuclear Information System (INIS)

    Fujimoto, Nozomu; Wang Hong

    2010-07-01

    The worldwide interests in the HTGR (High Temperature Gas-cooled Reactor) have been growing because the high temperature heat produced by the reactor can be utilized not only for efficient power generation but also for broad process heat applications, especially for thermo-chemical hydrogen production to fuel a prospective hydrogen economy in future. Presently only two HTGR reactors are operational in the world, including the HTTR (High Temperature Engineering Test Reactor) in Japan Atomic Energy Agency (JAEA) and the HTR-10 in the Institute of Nuclear and New Energy Technology (INET) of Tsinghua University in China. JAEA and INET have cooperated since 1986 in the field of HTGR development, particularly on the HTTR and HTR-10 projects. This report describes the cooperation activities on HTGR and nuclear hydrogen technology between JAEA and INET in 2009. (author)

  7. 78 FR 44954 - Advisory Board on Radiation and Worker Health (ABRWH or Advisory Board), National Institute for...

    Science.gov (United States)

    2013-07-25

    ... provided to the contact person below in advance of the meeting. Background: The Advisory Board was... President on a variety of policy and technical functions required to implement and effectively manage the new compensation program. Key functions of the Advisory Board include providing advice on the...

  8. Hydrogen as automotive fuel

    International Nuclear Information System (INIS)

    Ambrosini, G.; Ciancia, A.; Pede, G.; Brighigna, M.

    1993-01-01

    Hydrogen fueled vehicles may just be the answer to the air pollution problem in highly polluted urban environments where the innovative vehicle's air pollution abatement characteristics would justify its high operating costs as compared with those of conventional automotive alternatives. This paper examines the feasibility of hydrogen as an automotive fuel by analyzing the following aspects: the chemical-physical properties of hydrogen in relation to its use in internal combustion engines; the modifications necessary to adapt internal combustion engines to hydrogen use; hydrogen fuel injection systems; current production technologies and commercialization status of hydrogen automotive fuels; energy efficiency ratings; environmental impacts; in-vehicle storage systems - involving the use of hydrides, high pressure systems and liquid hydrogen storage systems; performance in terms of pay-load ratio; autonomous operation; and operating costs. With reference to recent trial results being obtained in the USA, an assessment is also made of the feasibility of the use of methane-hydrogen mixtures as automotive fuels. The paper concludes with a review of progress being made by ENEA (the Italian Agency for New Technology, Energy and the Environment) in the development of fuel storage and electronic fuel injection systems for hydrogen powered vehicles

  9. Screening of NiFe2O4 Nanoparticles as Oxygen Carrier in Chemical Looping Hydrogen Production

    DEFF Research Database (Denmark)

    Liu, Shuai; He, Fang; Huang, Zhen

    2016-01-01

    ) methods were used to prepare NiFe2O4 oxygen carriers. Samples were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) surface area measurement, as well as Barrett-Joyner-Halenda (BJH......The objective of this paper is to systematically investigate the influences of different preparation methods on the properties of NiFe2O4 nanoparticles as oxygen carrier in chemical looping hydrogen production (CLH). The solid state (SS), coprecipitation (CP), hydrothermal (HT), and sol-gel (SG...... gas (24% H2 + 24% CO + 12% CO2 + N2 balance), then reacted with steam to produce H2, and finally fully oxidized by air. The NiFe2O4 oxygen carrier prepared by the sol gel method showed the best capacity for hydrogen production and the highest recovery degree of lattice oxygen, in agreement...

  10. Liquid hydrogen production via hydrogen sulfide methane reformation

    Science.gov (United States)

    Huang, Cunping; T-Raissi, Ali

    Hydrogen sulfide (H 2S) methane (CH 4) reformation (H 2SMR) (2H 2S + CH 4 = CS 2 + 4H 2) is a potentially viable process for the removal of H 2S from sour natural gas resources or other methane containing gases. Unlike steam methane reformation that generates carbon dioxide as a by-product, H 2SMR produces carbon disulfide (CS 2), a liquid under ambient temperature and pressure-a commodity chemical that is also a feedstock for the synthesis of sulfuric acid. Pinch point analyses for H 2SMR were conducted to determine the reaction conditions necessary for no carbon lay down to occur. Calculations showed that to prevent solid carbon formation, low inlet CH 4 to H 2S ratios are needed. In this paper, we analyze H 2SMR with either a cryogenic process or a membrane separation operation for production of either liquid or gaseous hydrogen. Of the three H 2SMR hydrogen production flowsheets analyzed, direct liquid hydrogen generation has higher first and second law efficiencies of exceeding 80% and 50%, respectively.

  11. HR-EELS study of hydrogen bonding configuration, chemical and thermal stability of detonation nanodiamond films

    Energy Technology Data Exchange (ETDEWEB)

    Michaelson, Sh.; Akhvlediani, R. [Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Petit, T.; Girard, H.A.; Arnault, J.C. [CEA, LIST, Diamond Sensors Laboratory, F-91191 Gif sur Yvette (France); Hoffman, A., E-mail: choffman@tx.technion.ac.il [Schulich Faculty of Chemistry, Technion-Israel Institute of Technology, Haifa 32000 (Israel)

    2014-06-01

    Nano-diamond films composed of 3–10 nm grains prepared by the detonation method and deposited onto silicon substrates by drop-casting were examined by high resolution electron energy loss spectroscopy (HR-EELS), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and secondary ion mass spectroscopy (SIMS). The impact of (i) ex-situ ambient annealing at 400 °C and (ii) ex-situ hydrogenation on hydrogen bonding and its thermal stability were examined. In order to clarify the changes in hydrogen bonding configuration detected on the different surfaces as a function of thermal annealing, in-situ hydrogenation by thermally activated atomic hydrogen was performed and examined. This study provides direct evidence that the exposure to ambient conditions and medium temperature ambient annealing have a pronounced effect on the hydrogen-carbon bonding configuration onto the nano-diamond surfaces. In-situ 1000 °C annealing results in irreversible changes of the film surface and partial nano-diamond silicidation.

  12. Hydrogen storage using microporous carbon materials

    International Nuclear Information System (INIS)

    B Buczek; E Wolak

    2005-01-01

    In the present century hydrogen will be the most important source of energy and will replace petroleum and petroleum-derived products in the next future. Hydrogen is an almost ideal fuel, both because of its unlimited accessibility and for ecological reasons; the product of its combustion - water vapour - is neither any gaseous contamination nor a component of greenhouse gases. Nowadays hydrogen is applied in industrial processes, but may be also used as a source of house lighting and heating energy, for production of electricity, and as fuel for car engines. Fuel cells, applying reaction between hydrogen and oxygen for production of electricity have been for a long time used in the space technology. Application of hydrogen as fuel should give a possibility of storage and transfer of the high quality energy, i.e. the energy of a high exo-energetic ratio. Due to its low density, one of the main obstacles to the widespread use of hydrogen in energy sector is an efficient storage technology. At present, the methods of hydrogen storage are to liquefy and store in refrigerated containers, which is very expensive, or to store it in high - pressure gas cylinders at room temperature. Unfortunately, low storage density of hydrogen for the latter technique is a significant drawback. Between alternatives have been considered (chemical storage in irreversible hydrogen carriers like methanol or ammonia, reversible metal and chemical hydrides and adsorption in porous media), the latter one seems to lie the most promising. Physical adsorption is a method by which more gas can be stored at a lower pressure by means of Van der Waals interactions at the gas solid interface. Adsorptive storage is particularly promising for permanent gases, which need to be stored, transported, or used in ambient temperature. Thanks to the high density of adsorbed phase, adsorptive storage system could allow the storage of a high density of hydrogen at much lower pressures than compression and higher

  13. Integrating citizen advisory boards in public participation: Lessons from the field

    International Nuclear Information System (INIS)

    Snyder, S.

    1995-01-01

    Citizen advisory boards have been used successfully, particularly by the chemical industry, as programs for public participation. Now the U.S. Department of Energy (DOE) has responded to a growing demand for more direct citizen involvement in environmental restoration decision making. The experience of the site-specific advisory board at the department's Fernald Environmental Management Project near Cincinnati provides lessons that contribute to the development of a model for the most efficient use of citizen advisory boards

  14. Positively charged phosphorus as a hydrogen bond acceptor

    DEFF Research Database (Denmark)

    Hansen, Anne Schou; Du, Lin; Kjærgaard, Henrik Grum

    2014-01-01

    Phosphorus (P) is an element that is essential to the life of all organisms, and the atmospheric detection of phosphine suggests the existence of a volatile biogeochemical P cycle. Here, we investigate the ability of P to participate in the formation of OH···P hydrogen bonds. Three bimolecular......-stretching frequency red shifts and quantum chemical calculations, we find that P is an acceptor atom similar in strength to O and S and that all three P, O, and S atoms are weaker acceptors than N. The quantum chemical calculations show that both H and P in the OH···P hydrogen bond have partial positive charges......, as expected from their electronegativities. However, the electrostatic potentials show a negative potential area on the electron density surface around P that facilitates formation of hydrogen bonds....

  15. Magnetic field on board

    International Nuclear Information System (INIS)

    Estevez Radio, H.; Fernandez Arenal, C.A.

    1995-01-01

    Here, the calculation of the magnetic field on board ships is performed, using matrix calculus, in a similar way as when the magnetic field in matter is studied. Thus the final formulas are written in a more compact form and they are obtained through a simpler way, more suitable for the university education. (Author)

  16. Hydrogen Production Costs of Various Primary Energy Sources

    International Nuclear Information System (INIS)

    Choi, Jae Hyuk; Tak, Nam Il; Kim, Yong Hee; Park, Won Seok

    2005-01-01

    The limited resource and environmental impacts of fossil fuels are becoming more and more serious problems in the world. Consequently, hydrogen is in the limelight as a future alternative energy due to its clean combustion and inexhaustibility and a transition from the traditional fossil fuel system to a hydrogen-based energy system is under considerations. Several countries are already gearing the industries to the hydrogen economy to cope with the limitations of the current fossil fuels. Unfortunately, hydrogen has to be chemically separated from the hydrogen compounds in nature such as water by using some energy sources. In this paper, the hydrogen production costs of major primary energy sources are compared in consideration of the Korean situations. The evaluation methodology is based on the report of the National Academy of Science (NAS) of U.S

  17. Hospital ownership, decisions on supervisory board characteristics, and financial performance.

    Science.gov (United States)

    Kuntz, Ludwig; Pulm, Jannis; Wittland, Michael

    2016-01-01

    Dynamic and complex transformations in the hospital market increase the relevance of good corporate governance. However, hospital performance and the characteristics of supervisory boards differ depending on ownership. The question therefore arises whether hospital owners can influence performance by addressing supervisory board characteristics. The objective of this study is to explain differences in the financial performance of hospitals with regard to ownership by studying the size and composition of supervisory boards. The AMADEUS database was used to collect information on hospital financial performance in 2009 and 2010. Business and quality reports, hospital websites, and data from health insurer were used to obtain information on hospital and board characteristics. The resulting sample consisted of 175 German hospital corporations. We utilized ANOVA and regression analysis to test a mediation hypothesis that investigated whether decisions regarding board size and composition were associated with financial performance and could explain performance differences. Financial performance and board size and composition depend on ownership. An increase in board size and greater politician participation were negatively associated with all five tested measures of financial performance. Furthermore, an increase in physician participation was positively associated with one dimension of financial performance, whereas one negative relationship was identified for nurse and economist participation. For clerics, no associations were found. Decisions concerning board size and composition are important as they relate to hospital financial performance. We contribute to existing research by showing that, in addition to board size and physician participation, the participation of other professionals can also influence financial performance.

  18. Meeting Cathala-Letort named: the challenges of the processes engineering facing the hydrogen-energy; Journee Cathala-Letort intitulee: les defis du genie des procedes face a l'hydrogene-energie

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This document provides the presentations proposed during the day Cathala-Letort on the challenges of the processes engineering facing the hydrogen-energy. In the context of the greenhouse effect increase and the fossil energies resources decrease, it brings information on researches on hydrogen technologies, carbon dioxide sequestration, hydrogen supply, production, storage and distribution and the thermo-chemical cycles. (A.L.B.)

  19. Efficient room temperature hydrogen sensor based on UV-activated ZnO nano-network

    Science.gov (United States)

    Kumar, Mohit; Kumar, Rahul; Rajamani, Saravanan; Ranwa, Sapana; Fanetti, Mattia; Valant, Matjaz; Kumar, Mahesh

    2017-09-01

    Room temperature hydrogen sensors were fabricated from Au embedded ZnO nano-networks using a 30 mW GaN ultraviolet LED. The Au-decorated ZnO nano-networks were deposited on a SiO2/Si substrate by a chemical vapour deposition process. X-ray diffraction (XRD) spectrum analysis revealed a hexagonal wurtzite structure of ZnO and presence of Au. The ZnO nanoparticles were interconnected, forming nano-network structures. Au nanoparticles were uniformly distributed on ZnO surfaces, as confirmed by FESEM imaging. Interdigitated electrodes (IDEs) were fabricated on the ZnO nano-networks using optical lithography. Sensor performances were measured with and without UV illumination, at room temperate, with concentrations of hydrogen varying from 5 ppm to 1%. The sensor response was found to be ˜21.5% under UV illumination and 0% without UV at room temperature for low hydrogen concentration of 5 ppm. The UV-photoactivated mode enhanced the adsorption of photo-induced O- and O2- ions, and the d-band electron transition from the Au nanoparticles to ZnO—which increased the chemisorbed reaction between hydrogen and oxygen. The sensor response was also measured at 150 °C (without UV illumination) and found to be ˜18% at 5 ppm. Energy efficient low cost hydrogen sensors can be designed and fabricated with the combination of GaN UV LEDs and ZnO nanostructures.

  20. Overview of Cea studies on hydrogen production and related prospects for nuclear power

    International Nuclear Information System (INIS)

    Agator, J.M.; Guigon, A.

    2001-01-01

    The anticipated growth of the world energy demand and the increasing concern about the emission of greenhouse gases, with the objectives of limitation fixed by the Kyoto protocol, provide the impetus for the development of hydrogenous fuels, and especially that of hydrogen as energy carrier. The trend will be reinforced in the longer term with the progressive shortage of natural hydrocarbon fuels. Fuel cells used in stationary, transport and portable applications will probably be the most efficient hydrogen converter and the most promising decentralized energy technology of the coming decades. In order to contribute to the reduction of greenhouse gas emissions, the massive use of hydrogen for transport and stationary applications calls for the development of production processes compatible with low CO 2 emissions, thus limiting the use of fossil fuels (natural gas, oil, coal, etc.) as reagent or energy sources. Furthermore, the progressive exhaustion of economic fossil fuel reserves will ultimately make it necessary to extract hydrogen from water through CO 2 -free processes. With this prospect in view, base-load nuclear energy, besides renewable energies, can play an important role to produce hydrogen through electrolysis in the medium term, as can high temperature thermo-chemical water dissociation processes in the longer term. Starting from current research in the field of fuel cells and hydrogen storage systems, the CEA intends to implement a large R and D programme on hydrogen, continuing previous research and covering the aspects of production, transport and related safety requirements. This endeavour is intended to reinforce the contribution of the CEA to the national and European research effort on non-fossil energy sources, and to create new opportunities of international collaboration and networking. (authors)

  1. Hydrogen-related effects in crystalline semiconductors

    International Nuclear Information System (INIS)

    Haller, E.E.

    1988-08-01

    Recent experimental and theoretical information regarding the states of hydrogen in crystalline semiconductors is reviewed. The abundance of results illustrates that hydrogen does not preferentially occupy a few specific lattice sites but that it binds to native defects and impurities, forming a large variety of neutral and electrically active complexes. The study of hydrogen passivated shallow acceptors and donors and of partially passivated multivalent acceptors has yielded information on the electronic and real space structure and on the chemical composition of these complexes. Infrared spectroscopy, ion channeling, hydrogen isotope substitution and electric field drift experiments have shown that both static trigonal complexes as well as centers with tunneling hydrogen exist. Total energy calculations indicate that the charge state of the hydrogen ion which leads to passivation dominates, i.e., H + in p-type and H/sup /minus// in n-type crystals. Recent theoretical calculations indicate that is unlikely for a large fraction of the atomic hydrogen to exist in its neutral state, a result which is consistent with the total absence of any Electron Paramagnetic Resonance (EPR) signal. An alternative explanation for this result is the formation of H 2 . Despite the numerous experimental and theoretical results on hydrogen-related effects in Ge and Si there remains a wealth of interesting physics to be explored, especially in compound and alloy semiconductors. 6 refs., 6 figs

  2. Polyaniline as a material for hydrogen storage applications.

    Science.gov (United States)

    Attia, Nour F; Geckeler, Kurt E

    2013-07-12

    The main challenge of commercialization of the hydrogen economy is the lack of convenient and safe hydrogen storage materials, which can adsorb and release a significant amount of hydrogen at ambient conditions. Finding and designing suitable cost-effective materials are vital requirements to overcome the drawbacks of investigated materials. Because of its outstanding electronic, thermal, and chemical properties, the electrically conducting polyaniline (PANI) has a high potential in hydrogen storage applications. In this review, the progress in the use of different structures of conducting PANI, its nanocomposites as well as activated porous materials based on PANI as hydrogen storage materials is presented and discussed. The effect of the unique electronic properties based on the π-electron system in the backbone of these materials in view of the hydrogen uptake and the relevant mechanisms are highlighted. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Hydrogen - the energy source of the future

    International Nuclear Information System (INIS)

    Aakervik, Anne-Lise

    2001-01-01

    The use of hydrogen is an excellent way of reducing the emission of greenhouse gases. It causes no emission when used in fuel cells. Iceland has set itself the goal of becoming the world's first hydrogen society without emission of carbon dioxide and other greenhouse gases. In the USA, California has decided to concentrate on cars that do not pollute. Hydrogen power is then an interesting alternative. Germany, Japan and the USA are all concentrating on hydrogen. The world production of hydrogen is 50 million tons, 90 per cent of which is made from fossil material, 4 per cent by electrolysis of water. The largest consumers of hydrogen are the petroleum industry and the fertilizer industry. The sale of hydrogen in the refining industry has increased recently and is expected to rise substantially when the fuel cell technology is commercialized. At present, storage of hydrogen is the major problem. Gas storage at atmospheric pressure is inconvenient because of the large volumes required. Alternatives are storage as compressed gas under high pressure, liquid gas at low temperature, storage in metal hydrides or carbon materials, or chemically bound in methanol or ammonia

  4. Magnetic liquefier for hydrogen

    International Nuclear Information System (INIS)

    1992-01-01

    This document summarizes work done at the Astronautics Technology Center of the Astronautics Corporation of America (ACA) in Phase 1 of a four phase program leading to the development of a magnetic liquefier for hydrogen. The project involves the design, fabrication, installation, and operation of a hydrogen liquefier providing significantly reduced capital and operating costs, compared to present liquefiers. To achieve this goal, magnetic refrigeration, a recently developed, highly efficient refrigeration technology, will be used for the liquefaction process. Phase 1 project tasks included liquefier conceptual design and analysis, preliminary design of promising configurations, design selection, and detailed design of the selected design. Fabrication drawings and vendor specifications for the selected design were completed during detailed design. The design of a subscale, demonstration magnetic hydrogen liquefier represents a significant advance in liquefaction technology. The cost reductions that can be realized in hydrogen liquefaction in both the subscale and, more importantly, in the full-scale device are expected to have considerable impact on the use of liquid hydrogen in transportation, chemical, and electronic industries. The benefits to the nation from this technological advance will continue to have importance well into the 21st century

  5. Effects of reducing temperatures on the hydrogen storage capacity of double-walled carbon nanotubes with Pd loading.

    Science.gov (United States)

    Sheng, Qu; Wu, Huimin; Wexler, David; Liu, Huakun

    2014-06-01

    The effects of different temperatures on the hydrogen sorption characteristics of double-walled carbon nanotubes (DWCNTs) with palladium loading have been investigated. When we use different temperatures, the particle sizes and specific surface areas of the samples are different, which affects the hydrogen storage capacity of the DWCNTs. In this work, the amount of hydrogen storage capacity was determined (by AMC Gas Reactor Controller) to be 1.70, 1.85, 2.00, and 1.93 wt% for pristine DWCNTS and for 2%Pd/DWCNTs-300 degrees C, 2%Pd/DWCNTs-400 degrees C, and 2%Pd/DWCNTs-500 degrees C, respectively. We found that the hydrogen storage capacity can be enhanced by loading with 2% Pd nanoparticles and selecting a suitable temperature. Furthermore, the sorption can be attributed to the chemical reaction between atomic hydrogen and the dangling bonds of the DWCNTs.

  6. Efficiency of hydrogen gas production in a stand-alone solar hydrogen system

    International Nuclear Information System (INIS)

    Singh, K.; Tamakloe, R.Y.

    2003-01-01

    Many photovoltaic systems operate in a decentralised electricity producing system, or stand-alone mode and the total energy demand is met by the output of the photovoltaic array. The output of the photovoltaic system fluctuates and is unpredictable for many applications making some forms of energy storage system necessary. The role of storage medium is to store the excess energy produced by the photovoltaic arry, to absorb momentary power peaks and to supply energy during sunless periods. One of the storage modes is the use of electrochemical techniques, with batteries and water electrolysis as the most important examples. The present study includes three main parts: the first one is the hydrogen production form the electrolysis of water depending on the DC output current of the photovoltaic (PV) energy source and the charging of the battery. The second part presents the influence of various parameters on the efficiency of hydrogen gas production. The final part includes simulation studies with focus on solar hydrogen efficiency under the influence of various physical and chemical parameters. For a 50W panel-battery-electrolyser system, the dependence of volume of hydrogen gas on voltage, current and power yielded a maximum efficiency of 13.6% (author)

  7. Women on boards and corporate social responsibility

    Directory of Open Access Journals (Sweden)

    Francesca Gennari

    2016-02-01

    Full Text Available Data by EU Commission show a low representation of women on boards. The scope of this article is to read contemporary and according to a managerial approach the possible causes of this situation: the availability of skills possessed by women to cover top positions, the presence of binding or self-regulatory rules and the corporate culture towards CSR approach. Our research is focused on EU countries, where the gender equality on board is currently matter of attention and regulatory interventions. We conclude that the scarce presence of women in the boardrooms is not ascribable to a scarcity of expertise, but it is associated with a social background and a corporate culture not inspired by corporate global responsibility values. Regulatory interventions may accelerate the consciousness of gender balance on boards, but without companies’ commitment in CSR matters and without a clear vision of corporate global responsibility (including economic, social and environmental aspects, they tend to become additional tasks in the management of corporate compliance risk.

  8. Carbon nanotube materials for hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, A.C.; Parilla, P.A.; Jones, K.M.; Riker, G.; Heben, M.J. [National Renewable Energy Lab., Golden, CO (United States)

    1998-08-01

    Carbon single-wall nanotubes (SWNTs) are essentially elongated pores of molecular dimensions and are capable of adsorbing hydrogen at relatively high temperatures and low pressures. This behavior is unique to these materials and indicates that SWNTs are the ideal building block for constructing safe, efficient, and high energy density adsorbents for hydrogen storage applications. In past work the authors developed methods for preparing and opening SWNTs, discovered the unique adsorption properties of these new materials, confirmed that hydrogen is stabilized by physical rather than chemical interactions, measured the strength of interaction to be {approximately} 5 times higher than for adsorption on planar graphite, and performed infrared absorption spectroscopy to determine the chemical nature of the surface terminations before, during, and after oxidation. This year the authors have made significant advances in synthesis and characterization of SWNT materials so that they can now prepare gram quantities of high-purity SWNT samples and measure and control the diameter distribution of the tubes by varying key parameters during synthesis. They have also developed methods which purify nanotubes and cut nanotubes into shorter segments. These capabilities provide a means for opening the tubes which were unreactive to the oxidation methods that successfully opened tubes, and offer a path towards organizing nanotube segments to enable high volumetric hydrogen storage densities. They also performed temperature programmed desorption spectroscopy on high purity carbon nanotube material obtained from collaborator Prof. Patrick Bernier and finished construction of a high precision Seivert`s apparatus which will allow the hydrogen pressure-temperature-composition phase diagrams to be evaluated for SWNT materials.

  9. Contribution to the study of new hydrogen production, purification and storage processes

    International Nuclear Information System (INIS)

    Manaud, Jean-Pierre

    1984-01-01

    This research thesis addresses the various aspects of hydrogen production, purification and process within the scope of hydrogen-based energy production. Hydrogen production is achieved by water decomposition through a thermo-chemical process. The author reports the thermodynamic assessment of a water decomposition thermo-chemical cycle for chlorine and sulphur-related cycles. He reports the experimental investigation of hydrogen purification by selective diffusion, the study of contamination of a CeMg12 alloy by nitrogen, oxygen and water vapour with application to hydrogen storage under the form of hydrides [fr

  10. Fixed-bed hydrogen pyrolysis of rapeseed: product yields and compositions

    International Nuclear Information System (INIS)

    Onay, O.; Kockar, O.M.; Gaines, A.F.; Snape, C.E.

    2006-01-01

    The fixed-bed hydro pyrolysis tests have been conducted on a sample of rapeseed to investigate the effect of hydro pyrolysis on the yields and chemical structures of bio-oils, with a view to improving overall product quality. A ammonium dioxydithiomolybdenate catalyst has been used in some tests to further increase conversion. The maximum bio-oil yield of 84% was obtained in hydrogen atmosphere (with catalyst) at hydrogen pressure of 15 MPa, hydrogen flow rate of 10 dm 3 min -1 , hydro pyrolysis temperature of 520 degree C, and heating rate of 5 o Cmin -1 . Then this bio-oil was characterized by elemental analysis and some spectroscopic and chromatographic techniques. And finally, this bio-oil yield and chemical composition compared with oil obtained from fast pyrolysis condition

  11. Kinetics of chemical vapor deposition of boron on molybdenum

    International Nuclear Information System (INIS)

    Tanaka, W.; Nakaanishi, N.; Kato, E.

    1987-01-01

    Experimental rate data of chemical vapor deposition of boron by reduction of boron trichloride with hydrogen are analyzed to determine the reaction mechanism. The reaction orders with respect to the partial pressures of hydrogen and boron trichloride are one half and one third, respectively. It has been found that the outer layer of a deposited film is Mo/sub 2/B/sub 5/ and the inner layer is MoB by the use of X-ray diffraction and EPMA line analysis

  12. Achievement report on research and development in the Sunshine Project in fiscal 1980. Research on a hydrogen energy total system; 1980 nendo suiso energy total system no kenkyu seika hokokusho

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This paper describes research on a hydrogen energy total system. Fiscal 1980 has surveyed R/D technologies in the sectors anticipated to have large possibility of introducing hydrogen in Japan's energy systems in the future (ammonia/methanol industries, automobiles and aircraft fuel), and discussed the possibility of the introduction. The value factors (VF) applied to them are 1.7 for the ammonia industry, 1.1 to 1.6 for the methanol industry, 1.4 for gasoline as automobile and jet fuel, and 2.8 for jet fuel. Whether hydrogen would be introduced in all of these sectors depends on conditions of introducing hydrogen utilizing HTGR heat, and the VF of hydrogen against competing energies. Therefore, case studies were performed by using these factors as the parameters. If the VF is fixed and HTGR introduction speed is accelerated, introduction of hydrogen will be accelerated in the fields of chemical materials, air conditioning and process heat. On the other hand, the introduction will decrease in the automobile and aircraft fuel fields. If the methanol VF is made smaller, hydrogen introduction will be decelerated in the chemical industry field (methanol), and that in the air conditioning, automobiles and aircraft fuel fields will be accelerated. (NEDO)

  13. Proceedings of the workshop on elementary process in hydrogen recycling

    International Nuclear Information System (INIS)

    Itikawa, Yukikazu.

    1982-03-01

    On September 7 and 8, 1981, a workshop was held at the Institute of Plasma Physics to review the state of the art of the study of elementary processes in hydrogen recycling in fusion reactors. The processes considered are reflection, adsorption, trapping, particle-induced emission, chemical sputtering, and diffusion in metals. The present report is the proceedings of the workshop and contains rather comprehensive reviews each on the processes considered. The workshop was held as part of the joint research program of data compilation at the Research Information Center, Institute of Plasma Physics. (author)

  14. Chemical reaction on solid surface observed through isotope tracer technique

    International Nuclear Information System (INIS)

    Tanaka, Ken-ichi

    1983-01-01

    In order to know the role of atoms and ions on solid surfaces as the partners participating in elementary processes, the literatures related to the isomerization and hydrogen exchanging reaction of olefines, the hydrogenation of olefines, the metathesis reaction and homologation of olefines based on solid catalysts were reviewed. Various olefines, of which the hydrogen atoms were substituted with deuterium at desired positions, were reacted using various solid catalysts such as ZnO, K 2 CO 3 on C, MoS 2 (single crystal and powder) and molybdenum oxide (with various carriers), and the infra-red spectra of adsorbed olefines on catalysts, the isotope composition of reaction products and the production rate of the reaction products were measured. From the results, the bonding mode of reactant with the atoms and ions on solid surfaces, and the mechanism of the elementary process were considered. The author emphasized that the mechanism of the chemical reaction on solid surfaces and the role of active points or catalysts can be made clear to the considerable extent by combining isotopes suitably. (Yoshitake, I.)

  15. Advanced chemical hydride-based hydrogen generation/storage system for fuel cell vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Breault, R.W.; Rolfe, J. [Thermo Power Corp., Waltham, MA (United States)

    1998-08-01

    Because of the inherent advantages of high efficiency, environmental acceptability, and high modularity, fuel cells are potentially attractive power supplies. Worldwide concerns over clean environments have revitalized research efforts on developing fuel cell vehicles (FCV). As a result of intensive research efforts, most of the subsystem technology for FCV`s are currently well established. These include: high power density PEM fuel cells, control systems, thermal management technology, and secondary power sources for hybrid operation. For mobile applications, however, supply of hydrogen or fuel for fuel cell operation poses a significant logistic problem. To supply high purity hydrogen for FCV operation, Thermo Power`s Advanced Technology Group is developing an advanced hydrogen storage technology. In this approach, a metal hydride/organic slurry is used as the hydrogen carrier and storage media. At the point of use, high purity hydrogen will be produced by reacting the metal hydride/organic slurry with water. In addition, Thermo Power has conceived the paths for recovery and regeneration of the spent hydride (practically metal hydroxide). The fluid-like nature of the spent hydride/organic slurry will provide a unique opportunity for pumping, transporting, and storing these materials. The final product of the program will be a user-friendly and relatively high energy storage density hydrogen supply system for fuel cell operation. In addition, the spent hydride can relatively easily be collected at the pumping station and regenerated utilizing renewable sources, such as biomass, natural, or coal, at the central processing plants. Therefore, the entire process will be economically favorable and environmentally friendly.

  16. Metallic Hydrogen: A Game Changing Rocket Propellant

    Science.gov (United States)

    Silvera, Isaac F.

    2016-01-01

    The objective of this research is to produce metallic hydrogen in the laboratory using an innovative approach, and to study its metastability properties. Current theoretical and experimental considerations expect that extremely high pressures of order 4-6 megabar are required to transform molecular hydrogen to the metallic phase. When metallic hydrogen is produced in the laboratory it will be extremely important to determine if it is metastable at modest temperatures, i.e. remains metallic when the pressure is released. Then it could be used as the most powerful chemical rocket fuel that exists and revolutionize rocketry, allowing single-stage rockets to enter orbit and chemically fueled rockets to explore our solar system.

  17. Hydrogen and nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    Lucas, N J.D.

    1976-03-01

    There is much debate about the form and availability of energy supplies in the future. It is assumed that nuclear fuel is the only source of controlled energy. Energy inputs from the sun, the wind, the waves, the tides, and other sources not available in the form of fuels are not excluded. In this situation it has been argued that because the cost of transporting energy as a liquid or gaseous fuel is lower than the cost of transmitting energy as electricity it would be more effective to transmit and distribute energy from nuclear fuel in the form of a chemical fuel such as hydrogen. This argument has been critized by Hampson et al., (EAPA 1: 2200) who calculate that the reduced costs of transmission only outweigh the costs of production over distances so large that there appears no realistic application. These calculations neglect the time variation of electricity supply which is fundamental to the planning of an electricity supply system; they also do not appear to do justice to the relationship between the costs of hydrogen and electricity production in an integrated system. These points are included in the analysis presented here by means of the observation that hydrogen generated by nuclear plants with high capital cost and low running cost will be burned by the supply system itself in low-capital-cost plants, suitable for chemical fuels, in order to meet peak demands on the system. This establishes a relationship between the long-run marginal costs of electricity at various times of the day and the long-run marginal cost of hydrogen. These costs are then used to show that, in certain favorable, but common, circumstances, electrolytic hydrogen is the lower-cost source of energy. (from Introduction)

  18. Merging polygons on two-layer printed circuit board

    Directory of Open Access Journals (Sweden)

    Murov S. Yu.

    2011-12-01

    Full Text Available A method is proposed for solving the problem of connection of maximum number of isolated islands of metallized areas of the same chain, located on different layers of the printed circuit board. The method can be used in the automatic tracing of the boards.

  19. A composite of complex and chemical hydrides yields the first Al-based amidoborane with improved hydrogen storage properties.

    Science.gov (United States)

    Dovgaliuk, Iurii; Jepsen, Lars H; S