WorldWideScience

Sample records for hydrogen carrier system

  1. 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.)

  2. 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.)

  3. Development of a Practical Hydrogen Storage System Based on Liquid Organic Hydrogen Carriers and a Homogeneous Catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Craig [Hawaii Hydrogen Carriers, LLC, Honolulu, HI (United States); Brayton, Daniel [Hawaii Hydrogen Carriers, LLC, Honolulu, HI (United States); Jorgensen, Scott W. [General Motors, LLC, Warren, MI (United States). Research and Development Center. Chemical and Material Systems Lab.; Hou, Peter [General Motors, LLC, Warren, MI (United States). Research and Development Center. Chemical and Material Systems Lab.

    2017-03-24

    The objectives of this project were: 1) optimize a hydrogen storage media based on LOC/homogeneous pincer catalyst (carried out at Hawaii Hydrogen Carriers, LLC) and 2) develop space, mass and energy efficient tank and reactor system to house and release hydrogen from the media (carried out at General Motor Research Center).

  4. 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

  5. Carbon: Hydrogen carrier or disappearing skeleton?

    International Nuclear Information System (INIS)

    De Jong, K.P.; Van Wechem, H.M.H.

    1994-01-01

    The use of liquid hydrocarbons as energy carriers implies the use of carbon as a carrier for hydrogen to facilitate hydrogen transport and storage. The current trend for liquid energy carriers used in the transport sector is to maximize the load of hydrogen on the carbon carrier. The recently developed Shell Middle Distillate Hydrogenation process for the manufacture of high quality diesel from aromatic refinery streams fits this picture. In the future, the hydrogen required to raise the product H/C ratio will be increasingly produced via gasification of large amounts of heavy residues. In the light of the strong preference towards using liquid fuels in the transport sector, the Shell Middle Distillate Synthesis process to convert natural gas into diesel of very high quality is discussed. Finally, a few comments on the use of hydrogen without a carbon carrier are made. Long lead times and the likelihood of producing the 'first' hydrogen from fossil fuel are highlighted. 13 figs., 6 tabs., 5 refs

  6. New efficient hydrogen process production from organosilane hydrogen carriers derivatives

    Energy Technology Data Exchange (ETDEWEB)

    Brunel, Jean Michel [Unite URMITE, UMR 6236 CNRS, Faculte de Medecine et de Pharmacie, Universite de la Mediterranee, 27 boulevard Jean Moulin, 13385 Marseille 05 (France)

    2010-04-15

    While the source of hydrogen constitutes a significant scientific challenge, addressing issues of hydrogen storage, transport, and delivery is equally important. None of the current hydrogen storage options, liquefied or high pressure H{sub 2} gas, metal hydrides, etc.. satisfy criteria of size, costs, kinetics, and safety for use in transportation. In this context, we have discovered a methodology for the production of hydrogen on demand, in high yield, under kinetic control, from organosilane hydrogen carriers derivatives and methanol as co-reagent under mild conditions catalyzed by a cheap ammonium fluoride salt. Finally, the silicon by-products can be efficiently recycle leading to an environmentally friendly source of energy. (author)

  7. Formic Acid as a Hydrogen Energy Carrier

    KAUST Repository

    Eppinger, Jö rg; Huang, Kuo-Wei

    2016-01-01

    The high volumetric capacity (S3 g H-2/L) and its low toxicity and flammability under ambient conditions make formic acid a promising hydrogen energy carrier. Particularly, in the past decade, significant advancements have been achieved in catalyst development for selective hydrogen generation from formic acid. This Perspective highlights the advantages of this approach with discussions focused on potential applications in the transportation sector together with analysis of technical requirements, limitations, and costs.

  8. Formic Acid as a Hydrogen Energy Carrier

    KAUST Repository

    Eppinger, Jorg

    2016-12-15

    The high volumetric capacity (S3 g H-2/L) and its low toxicity and flammability under ambient conditions make formic acid a promising hydrogen energy carrier. Particularly, in the past decade, significant advancements have been achieved in catalyst development for selective hydrogen generation from formic acid. This Perspective highlights the advantages of this approach with discussions focused on potential applications in the transportation sector together with analysis of technical requirements, limitations, and costs.

  9. Hydrogen, an energy carrier with a future

    International Nuclear Information System (INIS)

    Zimmer, K.H.

    1975-01-01

    The inefficient use, associated with pollutants, of the fossil energy carriers coal, crude oil and natural gas, will deplete resources, if the energy demand increases exponentially, in the not-too-distant future. That is the reason why the hydrogen-energy concept gains in importance. This requires drastic changes in structure in a lot of technological fields. This task is only to be mastered if there is cooperation between all special fields, in order to facilitate the economical production, distribution and utilization of hydrogen. (orig.) [de

  10. Some aspects of hydrogen as a long-term energy carrier

    International Nuclear Information System (INIS)

    Quakernaat, J.; De Jong, K.P.; Van Wechem, H.M.H.; Okken, P.A.; Lako, P.; Ybema, J.R.

    1994-11-01

    Hydrogen as a secondary energy carrier received extensive and worldwide attention some ten to fifteen years ago. The developments in the energy market since then have reduced the interest in hydrogen. However, the increased concern for the environment and new technical options have brought hydrogen to the centre of attention once again. These considerations led to the organization of the National Hydrogen Seminar, held on 19 November 1993 at ECN, Petten, Netherlands. Eight experts in the field of hydrogen illustrated the possibilities and prospects of the production, storage and use of hydrogen as an energy carrier. In this report three of these contributions are presented, for which separate abstracts have been prepared. The first paper is on hydrogen in a global long-term perspective, in the second paper carbon is considered as a hydrogen carrier or as a disappearing skeleton, and in the third paper attention is paid to the cost effective integration of hydrogen in energy systems with CO 2 constraints

  11. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Steinbugler, M.; Dennis, E. [Princeton Univ., NJ (United States)] [and others

    1995-09-01

    For several years, researchers at Princeton University`s Center for Energy and Environmental Studies have carried out technical and economic assessments of hydrogen energy systems. Initially, we focussed on the long term potential of renewable hydrogen. More recently we have explored how a transition to renewable hydrogen might begin. The goal of our current work is to identify promising strategies leading from near term hydrogen markets and technologies toward eventual large scale use of renewable hydrogen as an energy carrier. Our approach has been to assess the entire hydrogen energy system from production through end-use considering technical performance, economics, infrastructure and environmental issues. This work is part of the systems analysis activity of the DOE Hydrogen Program. In this paper we first summarize the results of three tasks which were completed during the past year under NREL Contract No. XR-11265-2: in Task 1, we carried out assessments of near term options for supplying hydrogen transportation fuel from natural gas; in Task 2, we assessed the feasibility of using the existing natural gas system with hydrogen and hydrogen blends; and in Task 3, we carried out a study of PEM fuel cells for residential cogeneration applications, a market which might have less stringent cost requirements than transportation. We then give preliminary results for two other tasks which are ongoing under DOE Contract No. DE-FG04-94AL85803: In Task 1 we are assessing the technical options for low cost small scale production of hydrogen from natural gas, considering (a) steam reforming, (b) partial oxidation and (c) autothermal reforming, and in Task 2 we are assessing potential markets for hydrogen in Southern California.

  12. Comparative study of hydrogen and methanol as energy carriers

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Anna

    1998-06-01

    This report has been written with the purpose to compare hydrogen and methanol, with gasoline, as energy carriers for new energy systems in the future. This energy system must satisfy the demands for sustainable development. The report focuses on motor vehicle applications. A few different criteria has been developed to help form the characterisation method. The criteria proposed in this thesis are developed for an environmental comparison mainly based on emissions from combustion. The criteria concerns the following areas: Renewable resources, The ozone layer, The greenhouse effect, The acidification, and Toxic substances. In many ways, hydrogen may seem as a very good alternative compared with gasoline and diesel oil. Combustion of hydrogen in air results in water and small amounts of oxides of nitrogen. In this report, hydrogen produced from renewable resources is investigated. This is necessary to fulfill the demands for sustainable development. Today, however, steam reforming of fossil fuels represent 99% of the hydrogen production market. Problem areas connected with hydrogen use are for instance storage and distribution. Methanol has many advantages, while comparing methanol and gasoline, like lower emissions of nitrogen oxides and hydrocarbons, limited emissions of carbon dioxide and no sulphur content. Methanol can be produced from many different resources, for example natural gas, naphtha, oil, coal or peat, and biomass. To meet demands for sustainable production, methanol has to be produced from biomass Examination paper. 32 refs, 20 figs, 13 tabs

  13. Scenarios for total utilisation of hydrogen as an energy carrier in the future Danish energy system. Final report; Scenarier for samlet udnyttelse af brint som energibaerer i Danmarks fremtidige energisystem. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Hauge Petersen, A; Engberg Pedersen, T; Joergensen, K [and others

    2001-04-01

    This is the final report from a project performed for the Danish Energy Agency under its Hydrogen Programme. The project, which within the project group goes by the abbreviated title 'Hydrogen as an energy carrier', constructs and analyses different total energy scenarios for introducing hydrogen as an energy carrier, as energy storage medium and as a fuel in the future Danish energy system. The primary aim of the project is to study ways of handling the large deficits and surpluses of electricity from wind energy expected in the future Danish energy system. System-wide aspects of the choice of hydrogen production technologies, distribution methods, infrastructure requirements and conversion technologies are studied. Particularly, the possibility of using in the future the existing Danish natural gas distribution grid for carrying hydrogen will be assessed. For the year 2030, two scenarios are constructed: One using hydrogen primarily in the transportation sector, the other using it as a storage option for the centralised power plants still in operation by this year. For the year 2050, where the existing fossil power plants are expected to have been phased out completely, the scenarios for two possible developments are investigated: Either, there is a complete decentralisation of the use of hydrogen, converting and storing electricity surpluses into hydrogen in individual buildings, for later use in vehicles or regeneration of power and heat. Or, some centralised infrastructure is retained, such as hydrogen cavern stores and a network of vehicle hydrogen filling stations. The analysis is used to identify the components in an implementation strategy, for the most interesting scenarios, including a time sequence of necessary decisions and technology readiness. The report is in Danish, because it is part of the dissemination effort of the Hydrogen Committee, directed at the Danish population in general and the Danish professional community in particular. (au)

  14. Scenarios for total utilisation of hydrogen as an energy carrier in the future Danish energy system. Final report; Scenarier for samlet udnyttelse af brint som energibaerer i Danmarks fremtidige energisystem. Slutrapport

    Energy Technology Data Exchange (ETDEWEB)

    Hauge Petersen, A.; Engberg Pedersen, T.; Joergensen, K. (and others)

    2001-04-01

    This is the final report from a project performed for the Danish Energy Agency under its Hydrogen Programme. The project, which within the project group goes by the abbreviated title 'Hydrogen as an energy carrier', constructs and analyses different total energy scenarios for introducing hydrogen as an energy carrier, as energy storage medium and as a fuel in the future Danish energy system. The primary aim of the project is to study ways of handling the large deficits and surpluses of electricity from wind energy expected in the future Danish energy system. System-wide aspects of the choice of hydrogen production technologies, distribution methods, infrastructure requirements and conversion technologies are studied. Particularly, the possibility of using in the future the existing Danish natural gas distribution grid for carrying hydrogen will be assessed. For the year 2030, two scenarios are constructed: One using hydrogen primarily in the transportation sector, the other using it as a storage option for the centralised power plants still in operation by this year. For the year 2050, where the existing fossil power plants are expected to have been phased out completely, the scenarios for two possible developments are investigated: Either, there is a complete decentralisation of the use of hydrogen, converting and storing electricity surpluses into hydrogen in individual buildings, for later use in vehicles or regeneration of power and heat. Or, some centralised infrastructure is retained, such as hydrogen cavern stores and a network of vehicle hydrogen filling stations. The analysis is used to identify the components in an implementation strategy, for the most interesting scenarios, including a time sequence of necessary decisions and technology readiness. The report is in Danish, because it is part of the dissemination effort of the Hydrogen Committee, directed at the Danish population in general and the Danish professional community in particular. (au)

  15. Hydrogen: an energy carrier of the future

    Energy Technology Data Exchange (ETDEWEB)

    Hamerak, K

    1977-02-01

    Some advantages and fields of application of hydrogen are outlined in the introduction. Hydrogen production by conventional water electrolysis, by the thermochemical iron-chlorine cycle process, and by a new water electrolysis method still in the laboratory stage are dealt with in which the electrolysis voltage is considerably reduced by the action of solar UV light on an anode consisting of p-conducting material.

  16. A liquid organic carrier of hydrogen as a fuel for automobiles

    International Nuclear Information System (INIS)

    Taube, M.; Taube, P.

    1979-09-01

    A system of storing energy in a hydrogen containing fuel for the motor car is discussed. The recyclable liquid chemical carrier is: (Methylcyclohexane (liquid)) dehydrogenation (Toluene (liquid)) + (hydrogen (gas)). The reverse reaction, the hydrogenation of toluene, occurs in a regional plant connected to a source of hydrogen (electrolysis of water) with a significant by-product being heat at 200 0 C for district heating. The system is able to store hydrogen in liquid form under ambient temperature and pressure even in a small motor car. The concentration of hydrogen is 6.1 % by weight. The release of gaseous hydrogen from the liquid methylcyclohexane needs a chemical catalytic reactor having a temperature of 300 0 C and a pressure of some bars. This reaction has been well studied. The thermal energy for the dehydrogenation is taken from the exhaust gases at 780 0 C. A layout of the most important processes of the system is given. (Auth.)

  17. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Kreutz, T.G.; Steinbugler, M. [Princeton Univ., NJ (United States)] [and others

    1996-10-01

    In this report the authors describe results from technical and economic assessments carried out during the past year with support from the USDOE Hydrogen R&D Program. (1) Assessment of technologies for small scale production of hydrogen from natural gas. Because of the cost and logistics of transporting and storing hydrogen, it may be preferable to produce hydrogen at the point of use from more readily available energy carriers such as natural gas or electricity. In this task the authors assess near term technologies for producing hydrogen from natural gas at small scale including steam reforming, partial oxidation and autothermal reforming. (2) Case study of developing a hydrogen vehicle refueling infrastructure in Southern California. Many analysts suggest that the first widespread use of hydrogen energy is likely to be in zero emission vehicles in Southern California. Several hundred thousand zero emission automobiles are projected for the Los Angeles Basin alone by 2010, if mandated levels are implemented. Assuming that hydrogen vehicles capture a significant fraction of this market, a large demand for hydrogen fuel could evolve over the next few decades. Refueling a large number of hydrogen vehicles poses significant challenges. In this task the authors assess near term options for producing and delivering gaseous hydrogen transportation fuel to users in Southern California including: (1) hydrogen produced from natural gas in a large, centralized steam reforming plant, and delivered to refueling stations via liquid hydrogen truck or small scale hydrogen gas pipeline, (2) hydrogen produced at the refueling station via small scale steam reforming of natural gas, (3) hydrogen produced via small scale electrolysis at the refueling station, and (4) hydrogen from low cost chemical industry sources (e.g. excess capacity in refineries which have recently upgraded their hydrogen production capacity, etc.).

  18. Hydrogen as an energy carrier. 2. rev. and enlarged ed.

    International Nuclear Information System (INIS)

    Winter, C.J.; Nitsch, J.

    1991-01-01

    This book deals with the possibilities of an energetic utilisation of hydrogen. This energy carrier can be produced from the unlimited energy sources - solar energy, wind energy and hydropower - and from nuclear energy. It is also capable of one day supplementing or superseding the fossil energy carriers oil, coal and gas. What is special about the book is that it goes beyond a mere physical/technical description to discuss the economic and political aspects and ecological effects and requirements that are an essential part of sound energy planning today. Thus, the authors and editors outline the step-by-step development of a hydrogen economy, mainly based on solar energy, providing a solution to both the pollution problems caused by the use of fossil energy carriers and the energy requirements of the third world. (orig.) With 197 figs., 71 tabs

  19. 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

  20. Hydrogen as fuel carrier in PEM fuelcell for automobile applications

    Science.gov (United States)

    Sk, Mudassir Ali; Venkateswara Rao, K.; Ramana Rao, Jagirdar V.

    2015-02-01

    The present work focuses the application of nanostructured materials for storing of hydrogen in different carbon materials by physisorption method. To market a hydrogen-fuel cell vehicle as competitively as the present internal combustion engine vehicles, there is a need for materials that can store a minimum of 6.5wt% of hydrogen. Carbon materials are being heavily investigated because of their promise to offer an economical solution to the challenge of safe storage of large hydrogen quantities. Hydrogen is important as a new source of energy for automotive applications. It is clear that the key challenge in developing this technology is hydrogen storage. Combustion of fossil fuels and their overuse is at present a serious concern as it is creates severe air pollution and global environmental problems; like global warming, acid rains, ozone depletion in stratosphere etc. This necessitated the search for possible alternative sources of energy. Though there are a number of primary energy sources available, such as thermonuclear energy, solar energy, wind energy, hydropower, geothermal energy etc, in contrast to the fossil fuels in most cases, these new primary energy sources cannot be used directly and thus they must be converted into fuels, that is to say, a new energy carrier is needed. Hydrogen fuel cells are two to three times more efficient than combustion engines. As they become more widely available, they will reduce dependence on fossil fuels. In a fuel cell, hydrogen and oxygen are combined in an electrochemical reaction that produces electricity and, as a byproduct, water.

  1. Hydrogen-metal systems

    International Nuclear Information System (INIS)

    Wenzl, H.; Springer, T.

    1976-01-01

    A survey is given on the alloys of metal crystals with hydrogen. The system niobium-hydrogen and its properties are especially dealt with: diffusion and heat of solution of hydrogen in the host crystal, phase diagram, coherent and incoherent phase separation, application of metal-hydrogen systems in technology. Furthermore, examples from research work in IFF (Institut fuer Festkoerperforschung) of the Nuclear Research Plant, Juelich, in the field of metal-H systems are given in summary form. (GSC) [de

  2. Renewable energy carriers: Hydrogen or liquid air/nitrogen?

    International Nuclear Information System (INIS)

    Li Yongliang; Chen Haisheng; Zhang Xinjing; Tan Chunqing; Ding Yulong

    2010-01-01

    The world's energy demand is met mainly by the fossil fuels today. The use of such fuels, however, causes serious environmental issues, including global warming, ozone layer depletion and acid rains. A sustainable solution to the issues is to replace the fossil fuels with renewable ones. Implementing such a solution, however, requires overcoming a number of technological barriers including low energy density, intermittent supply and mobility of the renewable energy sources. A potential approach to overcoming these barriers is to use an appropriate energy carrier, which can store, transport and distribute energy. The work to be reported in this paper aims to assess and compare a chemical energy carrier, hydrogen, with a physical energy carrier, liquid air/nitrogen, and discuss potential applications of the physical carrier. The ocean energy is used as an example of the renewable energy sources in the work. The assessment and comparison are carried out in terms of the overall efficiency, including production, storage/transportation and energy extraction. The environmental impact, waste heat recovery and safety issues are also considered. It is found that the physical energy carrier may be a better alternative to the chemical energy carrier under some circumstances, particularly when there are waste heat sources.

  3. Energy infrastructure: hydrogen energy system

    Energy Technology Data Exchange (ETDEWEB)

    Veziroglu, T N

    1979-02-01

    In a hydrogen system, hydrogen is not a primary source of energy, but an intermediary, an energy carrier between the primary energy sources and the user. The new unconventional energy sources, such as nuclear breeder reactors, fusion reactors, direct solar radiation, wind energy, ocean thermal energy, and geothermal energy have their shortcomings. These shortcomings of the new sources point out to the need for an intermediary energy system to form the link between the primary energy sources and the user. In such a system, the intermediary energy form must be transportable and storable; economical to produce; and if possible renewable and pollution-free. The above prerequisites are best met by hydrogen. Hydrogen is plentiful in the form of water. It is the cheapest synthetic fuel to manufacture per unit of energy stored in it. It is the least polluting of all of the fuels, and is the lightest and recyclable. In the proposed system, hydrogen would be produced in large plants located away from the consumption centers at the sites where primary new energy sources and water are available. Hydrogen would then be transported to energy consumption centers where it would be used in every application where fossil fuels are being used today. Once such a system is established, it will never be necessary to change to any other energy system.

  4. Renewable carbohydrates are a potential high-density hydrogen carrier

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Y.-H. Percival [Biological Systems Engineering Department, 210-A Seitz Hall, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); Institute for Critical Technology and Applied Sciences (ICTAS), Virginia Polytechnic Institute and State University, Blacksburg, VA 24061 (United States); DOE BioEnergy Science Center (BESC), Oak Ridge, TN 37831 (United States)

    2010-10-15

    The possibility of using renewable biomass carbohydrates as a potential high-density hydrogen carrier is discussed here. Gravimetric density of polysaccharides is 14.8 H{sub 2} mass% where water can be recycled from PEM fuel cells or 8.33% H{sub 2} mass% without water recycling; volumetric densities of polysaccharides are >100 kg of H{sup 2}/m{sup 3}. Renewable carbohydrates (e.g., cellulosic materials and starch) are less expensive based on GJ than are other hydrogen carriers, such as hydrocarbons, biodiesel, methanol, ethanol, and ammonia. Biotransformation of carbohydrates to hydrogen by cell-free synthetic (enzymatic) pathway biotransformation (SyPaB) has numerous advantages, such as high product yield (12 H{sub 2}/glucose unit), 100% selectivity, high energy conversion efficiency (122%, based on combustion energy), high-purity hydrogen generated, mild reaction conditions, low-cost of bioreactor, few safety concerns, and nearly no toxicity hazards. Although SyPaB may suffer from current low reaction rates, numerous approaches for accelerating hydrogen production rates are proposed and discussed. Potential applications of carbohydrate-based hydrogen/electricity generation would include hydrogen bioreactors, home-size electricity generators, sugar batteries for portable electronics, sugar-powered passenger vehicles, and so on. Developments in thermostable enzymes as standardized building blocks for cell-free SyPaB projects, use of stable and low-cost biomimetic NAD cofactors, and accelerating reaction rates are among the top research and development priorities. International collaborations are urgently needed to solve the above obstacles within a short time. (author)

  5. Measurements of hydrogen concentration in liquid sodium by using an inert gas carrier method

    International Nuclear Information System (INIS)

    Funada, T.; Nihei, I.; Yuhara, S.; Nakasuji, T.

    1979-01-01

    A technique was developed to measure the hydrogen level in liquid sodium using an inert gas carrier method. Hydrogen was extracted into an inert gas from sodium through a thin nickel membrane in the form of a helically wound tube. The amount of hydrogen in the inert gas was analyzed by gas chromatography. The present method is unique in that it can be used over the wide range of sodium temperatures (150 to 700 0 C) and has no problems associated with vacuum systems. The partial pressure of hydrogen in sodium was determined as a function of cold-trap temperature (T/sub c/). Sieverts' constant (K/sub s/) was determined as a function of sodium temperature (T). From Sieverts' constant, the solubility of hydrogen in sodium is calculated. It was found that other impurities in sodium, such as (O) and (OH), have little effect on the hydrogen pressure in the sodium loop

  6. Hydrogen peroxide as a sustainable energy carrier: Electrocatalytic production of hydrogen peroxide and the fuel cell

    International Nuclear Information System (INIS)

    Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D.

    2012-01-01

    This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal–oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

  7. Hydrogen Peroxide as a Sustainable Energy Carrier: Electrocatalytic Production of Hydrogen Peroxide and the Fuel Cell.

    Science.gov (United States)

    Fukuzumi, Shunichi; Yamada, Yusuke; Karlin, Kenneth D

    2012-11-01

    This review describes homogeneous and heterogeneous catalytic reduction of dioxygen with metal complexes focusing on the catalytic two-electron reduction of dioxygen to produce hydrogen peroxide. Whether two-electron reduction of dioxygen to produce hydrogen peroxide or four-electron O 2 -reduction to produce water occurs depends on the types of metals and ligands that are utilized. Those factors controlling the two processes are discussed in terms of metal-oxygen intermediates involved in the catalysis. Metal complexes acting as catalysts for selective two-electron reduction of oxygen can be utilized as metal complex-modified electrodes in the electrocatalytic reduction to produce hydrogen peroxide. Hydrogen peroxide thus produced can be used as a fuel in a hydrogen peroxide fuel cell. A hydrogen peroxide fuel cell can be operated with a one-compartment structure without a membrane, which is certainly more promising for the development of low-cost fuel cells as compared with two compartment hydrogen fuel cells that require membranes. Hydrogen peroxide is regarded as an environmentally benign energy carrier because it can be produced by the electrocatalytic two-electron reduction of O 2 , which is abundant in air, using solar cells; the hydrogen peroxide thus produced could then be readily stored and then used as needed to generate electricity through the use of hydrogen peroxide fuel cells.

  8. Photochemical hydrogen production system

    International Nuclear Information System (INIS)

    Copeland, R.J.

    1990-01-01

    Both technical and economic factors affect the cost of producing hydrogen by photochemical processes. Technical factors include the efficiency and the capital and operating costs of the renewable hydrogen conversion system; economic factors include discount rates, economic life, credit for co-product oxygen, and the value of the energy produced. This paper presents technical and economic data for a system that generates on-peak electric power form photochemically produced hydrogen

  9. Electrochemical hydrogen Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Digby Macdonald

    2010-08-09

    As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. In this report, research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not

  10. Electrochemical hydrogen Storage Systems

    International Nuclear Information System (INIS)

    Macdonald, Digby

    2010-01-01

    As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. In this report, research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not described in the

  11. Autothermal hydrogen storage and delivery systems

    Science.gov (United States)

    Pez, Guido Peter [Allentown, PA; Cooper, Alan Charles [Macungie, PA; Scott, Aaron Raymond [Allentown, PA

    2011-08-23

    Processes are provided for the storage and release of hydrogen by means of dehydrogenation of hydrogen carrier compositions where at least part of the heat of dehydrogenation is provided by a hydrogen-reversible selective oxidation of the carrier. Autothermal generation of hydrogen is achieved wherein sufficient heat is provided to sustain the at least partial endothermic dehydrogenation of the carrier at reaction temperature. The at least partially dehydrogenated and at least partially selectively oxidized liquid carrier is regenerated in a catalytic hydrogenation process where apart from an incidental employment of process heat, gaseous hydrogen is the primary source of reversibly contained hydrogen and the necessary reaction energy.

  12. Thermal generation and mobility of charge carriers in collective proton transport in hydrogen-bonded chains

    International Nuclear Information System (INIS)

    Peyrard, M.; Boesch, R.; Kourakis, I.

    1991-01-01

    The transport of protons in hydrogen-bonded systems is a long standing problem which has not yet obtained a satisfactorily theoretical description. Although this problem was examined first for ice, it is relevant in many systems and in particular in biology for the transport along proteins or for proton conductance across membranes, an essential process in cell life. The broad relevance makes the study of proton conduction very appealing. Since the original work of Bernal and Fowler on ice, the idea that the transport occurs through chains of hydrogen bonds has been well accepted. Such ''proton wires'' were invoked by Nagle and Morowitz for proton transport across membranes proteins and more recently across lipid bilayers. In this report, we assume the existence of such an hydrogen-bonded chain and discuss its consequences on the dynamics of the charge carriers. We show that this assumption leads naturally to the idea of soliton transport and we put a special emphasis on the role of the coupling between the protons and heavy ions motions. The model is presented. We show how the coupling affects strongly the dynamics of the charge carriers and we discuss the role it plays in the thermal generation of carriers. The work presented has been performed in 1986 and 87 with St. Pnevmatikos and N. Flyzanis and was then completed in collaboration with D. Hochstrasser and H. Buettner. Therefore the results presented in this part are not new but we think that they are appropriate in the context of this multidisciplinary workshop because they provide a rather complete example of the soliton picture for proton conduction. This paper discusses the thermal generation of the charge carriers when the coupling between the protons and heavy ions dynamics is taken into account. The results presented in this part are very recent and will deserve further analysis but they already show that the coupling can assist for the formation of the charge carriers

  13. 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

  14. 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

  15. Design and Development of New Carbon-Based Sorbent Systems for an Effective Containment of Hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Alan C. Cooper

    2012-05-03

    This is a summary for work performed under cooperative agreement DE FC36 04GO14006 (Design and Development of New Carbon-based Sorbent Systems for an Effective Containment of Hydrogen). The project was directed to discover new solid and liquid materials that use reversible catalytic hydrogenation as the mechanism for hydrogen capture and storage. After a short period of investigation of solid materials, the inherent advantages of storing and transporting hydrogen using liquid-phase materials focused our attention exclusively on organic liquid hydrogen carriers (liquid carriers). While liquid carriers such as decalin and methylcyclohexane were known in the literature, these carriers suffer from practical disadvantages such as the need for very high temperatures to release hydrogen from the carriers and difficult separation of the carriers from the hydrogen. In this project, we were successful in using the prediction of reaction thermodynamics to discover liquid carriers that operate at temperatures up to 150 C lower than the previously known carriers. The means for modifying the thermodynamics of liquid carriers involved the use of certain molecular structures and incorporation of elements other than carbon into the carrier structure. The temperature decrease due to the more favorable reaction thermodynamics results in less energy input to release hydrogen from the carriers. For the first time, the catalytic reaction required to release hydrogen from the carriers could be conducted with the carrier remaining in the liquid phase. This has the beneficial effect of providing a simple means to separate the hydrogen from the carrier.

  16. Hydrogen as an energy carrier and its production by nuclear power

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-05-01

    The impact of power generation on environment is becoming an ever increasing concern in decision making when considering the energy options and power systems required by a country in order to sustain its economic growth and development. Hydrogen is a strong emerging candidate with a significant role as a clean, environmentally benign and safe to handle major energy carrier in the future. Its enhanced utilization in distributed power generation as well as in propulsion systems for mobile applications will help to significantly mitigate the strong negative effects on the environment. It ia also the nuclear power that will be of utmost importance in the energy supply of many countries over the next decades. The development of new, innovative reactor concepts utilizing passive safety features for process heat and electricity generation are considered by many to play a substantial role in the world`s energy future in helping to reduce greenhouse gas emissions. This report produced by IAEA documents past and current activities in Member States in the development of hydrogen production as an energy carrier and its corresponding production through the use of nuclear power. It provides an introduction to nuclear technology as a means of producing hydrogen or other upgraded fuels and to the energy carries hydrogen and its main fields of application. Emphasis is placed on high-temperature reactor technology which can achieve the simultaneous generation of electricity and the production of high-temperature process heat Refs, figs, tabs

  17. Hydrogen as an energy carrier and its production by nuclear power

    International Nuclear Information System (INIS)

    1999-05-01

    The impact of power generation on environment is becoming an ever increasing concern in decision making when considering the energy options and power systems required by a country in order to sustain its economic growth and development. Hydrogen is a strong emerging candidate with a significant role as a clean, environmentally benign and safe to handle major energy carrier in the future. Its enhanced utilization in distributed power generation as well as in propulsion systems for mobile applications will help to significantly mitigate the strong negative effects on the environment. It ia also the nuclear power that will be of utmost importance in the energy supply of many countries over the next decades. The development of new, innovative reactor concepts utilizing passive safety features for process heat and electricity generation are considered by many to play a substantial role in the world's energy future in helping to reduce greenhouse gas emissions. This report produced by IAEA documents past and current activities in Member States in the development of hydrogen production as an energy carrier and its corresponding production through the use of nuclear power. It provides an introduction to nuclear technology as a means of producing hydrogen or other upgraded fuels and to the energy carries hydrogen and its main fields of application. Emphasis is placed on high-temperature reactor technology which can achieve the simultaneous generation of electricity and the production of high-temperature process heat

  18. Cyclodextrins in drug carrier systems.

    Science.gov (United States)

    Uekama, K; Otagiri, M

    1987-01-01

    One of the important characteristics of cyclodextrins is the formation of an inclusion complex with a variety of drug molecules in solution and in the solid state. As a consequence of intensive basic research, exhaustive toxic studies, and realization of industrial production during the past decade, there seem to be no more barriers for the practical application of natural cyclodextrins in the biomedical field. Recently, a number of cyclodextrin derivatives and cyclodextrin polymers have been prepared to obtain better inclusion abilities than parent cyclodextrins. The natural cyclodextrins and their synthetic derivatives have been successfully utilized to improve various drug properties, such as solubility, dissolution and release rates, stability, or bioavailability. In addition, the enhancement of drug activity, selective transfer, or the reduction of side effects has been achieved by means of inclusion complexation. The drug-cyclodextrin complex is generally formed outside of the body and, after administration, it dissociates, releasing the drug into the organism in a fast and nearly uniform manner. In the biomedical application of cyclodextrins, therefore, particular attention should be directed to the magnitude of the stability constant of the inclusion complex. In the case of parenteral application, a rather limited amount of work has been done because the cyclodextrins in the drug carrier systems have to be more effectively designed to compete with various biological components in the circulatory system. However, the works published thus far apparently indicate that the inclusion phenomena of cyclodextrin analogs may allow the rational design of drug formulation and that the combination of molecular encapsulation with other carrier systems will become a very effective and valuable method for the development of a new drug delivery system in the near future.

  19. Hydrogen production from biomass by biological systems

    International Nuclear Information System (INIS)

    Sharifan, H.R.; Qader, S.

    2009-01-01

    Hydrogen gas is seen as a future energy carrier, not involved in 'greenhouse' gas and its released energy in combustion can be converted to electric power. Biological system with low energy can produce hydrogen compared to electrochemical hydrogen production via solar battery-based water splitting which requires the use of solar batteries with high energy requirements. The biological hydrogen production occurs in microalgae and cyanobacteria by photosynthesis. They consume biochemical energy to produce molecular hydrogen. Hydrogen in some algae is an anaerobic production in the absence of light. In cyanobacteria the hydrogen production simultaneously happens with nitrogen fixation, and also catalyzed by nitrogenase as a side reaction. Hydrogen production by photosynthetic bacteria is mediated by nitrogenase activity, although hydrogenases may be active for both hydrogen production and hydrogen uptake under some conditions. Genetic studies on photosynthetic microorganisms have markedly increased in recent times, relatively few genetic engineering studies have focused on altering the characteristics of these microorganisms, particularly with respect to enhancing the hydrogen-producing capabilities of photosynthetic bacteria and cyanobacteria. (author)

  20. Hydrogen and Biofuels - A Modeling Analysis of Competing Energy Carriers for Western Europe

    Energy Technology Data Exchange (ETDEWEB)

    Guel, Timur; Kypreos, Socrates; Barreto, Leonardo

    2007-07-01

    This paper deals with the prospects of hydrogen and biofuels as energy carriers in the Western European transportation sector. The assessment is done by combining the US hydrogen analysis H2A models for the design of hydrogen production and delivery chains, and the Western European Hydrogen Markal Model EHM with a detailed representation of biofuels, and the European electricity and transportation sector. The paper derives policy recommendations to support the market penetration of hydrogen and biofuels, and investigates learning interactions between the different energy carriers. (auth)

  1. Economic impacts of hydrogen as an energy carrier in European countries

    International Nuclear Information System (INIS)

    Wietschel, Martin; Seydel, Philipp

    2007-01-01

    The two objectives of this paper are to identify possible sectoral shifts and employment effects due to the application of hydrogen in the energy system for selected European countries till 2030. This is based on assumptions about the market penetration of hydrogen as an energy carrier, an analysis of the competitiveness of EU countries in this technology field and input-output model calculations. The analysis showed that the introduction of hydrogen leads to significant shifts between economic sectors and, as a policy recommendation, it is concluded that the required workforce skills in hydrogen technologies should be available in time in order to be properly prepared for this. Some employment gains are possible for the EU Member States analysed if the introduction of hydrogen does not result in significant changes in export/import flows. However, the lead market analysis also showed that the competitiveness of EU countries varies significantly and that, viewed as a whole, Europe is in danger of falling behind its main competitors. This may lead to job losses because the industry branches affected - automotive and plant manufacturers - represent key sectors for the EU. One policy goal, therefore, especially for countries with a large share of automobile and plant manufacturing, is to aim to be a lead market for hydrogen and fuel cells. (author)

  2. 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.

  3. Hydrogen storage and generation system

    Science.gov (United States)

    Dentinger, Paul M.; Crowell, Jeffrey A. W.

    2010-08-24

    A system for storing and generating hydrogen generally and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses the beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

  4. Seasonal storage and alternative carriers: A flexible hydrogen supply chain model

    International Nuclear Information System (INIS)

    Reuß, M.; Grube, T.; Robinius, M.; Preuster, P.; Wasserscheid, P.; Stolten, D.

    2017-01-01

    Highlights: •Techno-economic model of future hydrogen supply chains. •Implementation of liquid organic hydrogen carriers into a hydrogen mobility analysis. •Consideration of large-scale seasonal storage for fluctuating renewable hydrogen production. •Implementation of different technologies for hydrogen storage and transportation. -- Abstract: A viable hydrogen infrastructure is one of the main challenges for fuel cells in mobile applications. Several studies have investigated the most cost-efficient hydrogen supply chain structure, with a focus on hydrogen transportation. However, supply chain models based on hydrogen produced by electrolysis require additional seasonal hydrogen storage capacity to close the gap between fluctuation in renewable generation from surplus electricity and fuelling station demand. To address this issue, we developed a model that draws on and extends approaches in the literature with respect to long-term storage. Thus, we analyse Liquid Organic Hydrogen Carriers (LOHC) and show their potential impact on future hydrogen mobility. We demonstrate that LOHC-based pathways are highly promising especially for smaller-scale hydrogen demand and if storage in salt caverns remains uncompetitive, but emit more greenhouse gases (GHG) than other gaseous or hydrogen ones. Liquid hydrogen as a seasonal storage medium offers no advantage compared to LOHC or cavern storage since lower electricity prices for flexible operation cannot balance the investment costs of liquefaction plants. A well-to-wheel analysis indicates that all investigated pathways have less than 30% GHG-emissions compared to conventional fossil fuel pathways within a European framework.

  5. Prospects for hydrogen in the German energy system

    International Nuclear Information System (INIS)

    Hake, J.-F.; Linssen, J.; Walbeck, M.

    2006-01-01

    The focus of the paper concerns the current discussion on the contribution of the hydrogen economy to a 'sustainable energy system'. It considers whether advantages for the environmental situation and energy carrier supply can be expected from the already visible future characteristics of hydrogen as a new secondary energy carrier. Possible production paths for hydrogen from hydrocarbon-based, renewable or carbon-reduced/-free primary energy carriers are evaluated with respect to primary energy use and CO 2 emissions from the fuel cycle. Hydrogen has to be packaged by compression or liquefaction, transported by surface vehicles or pipelines, stored and transferred to the end user. Whether generated by electrolysis or by reforming, and even if produced locally at filling stations, the gaseous or liquid hydrogen has to undergo these market processes before it can be used by the customer. In order to provide an idea of possible markets with special emphasis on the German energy sector, a technical systems analysis of possible hydrogen applications is performed for the stationary, mobile and portable sector. Furthermore, different 'business as usual' scenarios are analysed for Germany, Europe and the World concerning end energy use in different sectors. The very small assumed penetration of hydrogen in the analysed scenarios up to the year 2050 indicates that the hydrogen economy is a long-term option. With reference to the assumed supply paths and analysed application possibilities, hydrogen can be an option for clean energy use if hydrogen can be produced with carbon-reduced or -free primary energy carriers like renewable energy or biomass. However, the energetic use of hydrogen competes with the direct use of clean primary energy and/or with the use of electric energy based on renewable primary energy. As a substitution product for other secondary energy carriers hydrogen is therefore under pressure of costs and/or must have advantages in comparison to the use of

  6. Enhancing Charge Carrier Lifetime in Metal Oxide Photoelectrodes through Mild Hydrogen Treatment

    KAUST Repository

    Jang, Ji-Wook; Friedrich, Dennis; Mü ller, Sö nke; Lamers, Marlene; Hempel, Hannes; Lardhi, Sheikha F.; Cao, Zhen; Harb, Moussab; Cavallo, Luigi; Heller, René ; Eichberger, Rainer; van de Krol, Roel; Abdi, Fatwa F.

    2017-01-01

    and are relatively cheap, are particularly interesting, but high efficiency is still hindered by the poor carrier transport properties (i.e., carrier mobility and lifetime). Here, a mild hydrogen treatment is introduced to bismuth vanadate (BiVO4), which is one

  7. Ocean thermal plantships for production of ammonia as the hydrogen carrier.

    Energy Technology Data Exchange (ETDEWEB)

    Panchal, C.B.; Pandolfini, P. P.; Kumm, W. H.; Energy Systems; Johns Hopkins Univ.; Arctic Energies, Ltd.

    2009-12-02

    completing project tasks that consist of updating the John Hopkins University/Applied Physics Laboratory (JHU/APL) pilot plantship design and extrapolating it to commercial plantships, evaluating a new energy-efficient ammonia synthesis process, evaluating the co-production of desalinated water on plantships, and developing a conceptual design of a satellite plantships system for commercial-scale ammonia production. In addition, an industrial workshop was organized to present the results and develop future goals for commercialization of ocean thermal plantships by 2015. The following goals, arranged in chronological order, were examined at the workshop: (1) Global displacement of petroleum-fuel-based (diesel, fuel oil, naphtha) power generation for freeing up these fuels for transportation, chemical feedstock, and other high-valued uses; (2) At-sea production of desalinated water for regions of critical water shortages; (3) Displacement of carbon-based feed stocks and energy for production of ammonia fertilizers; (4) Development of hydrogen supply to allow economic processing of heavy crude oils and upgrading oil sands; (5) Development of ammonia-fueled distributed energy to displace natural-gas fueled power generation to free up natural gas for higher-value uses and the mitigation of issues associated with imported liquefied natural gas (LNG); and (6) Use of ammonia as a hydrogen carrier for transportation.

  8. [Feasibility investigation of hydrogen instead of helium as carrier gas in the determination of five organophosphorus pesticides by gas chromatography-mass spectrometry].

    Science.gov (United States)

    Liu, Zhenxue; Zhou, Shixue

    2015-01-01

    Helium is almost the only choosable carrier gas used in gas chromatography-mass spectrometry (GC-MS). A mixed standard solution of five organophosphorus pesticides was analyzed by using GC-MS, and hydrogen or helium as carrier gas, so as to study the feasibility of hydrogen instead of helium as carrier gas for the determination of organophosphorus pesticides. Combining a mass spectrum database built by ourselves, the results were deconvolved and identified by Automated Mass Spectral Deconvolution & Identification System (AMDIS32), a software belonging to the workstation of the instrument. Then, the statistical software, IBM SPSS Statistics 19.0 was used for the clustering analysis of the data. The results indicated that when hydrogen was used as carrier gas, the peaks of the pesticides detected were slightly earlier than those when helium used as carrier gas, but the resolutions of the chromatographic peaks were lower, and the fraction good indices (Frac. Good) were lower, too. When hydrogen was used as carrier gas, the signals of the pesticides were unstable, the measuring accuracies of the pesticides were reduced too, and even more, some compounds were undetectable. Therefore, considering the measuring accuracy, the signal stability, and the safety, etc., hydrogen should be cautiously used as carrier gas in the determination of organophosphorus pesticides by GC-MS.

  9. Enhancing Charge Carrier Lifetime in Metal Oxide Photoelectrodes through Mild Hydrogen Treatment

    KAUST Repository

    Jang, Ji-Wook

    2017-08-25

    Widespread application of solar water splitting for energy conversion is largely dependent on the progress in developing not only efficient but also cheap and scalable photoelectrodes. Metal oxides, which can be deposited with scalable techniques and are relatively cheap, are particularly interesting, but high efficiency is still hindered by the poor carrier transport properties (i.e., carrier mobility and lifetime). Here, a mild hydrogen treatment is introduced to bismuth vanadate (BiVO4), which is one of the most promising metal oxide photoelectrodes, as a method to overcome the carrier transport limitations. Time-resolved microwave and terahertz conductivity measurements reveal more than twofold enhancement of the carrier lifetime for the hydrogen-treated BiVO4, without significantly affecting the carrier mobility. This is in contrast to the case of tungsten-doped BiVO4, although hydrogen is also a donor type dopant in BiVO4. The enhancement in carrier lifetime is found to be caused by significant reduction of trap-assisted recombination, either via passivation or reduction of deep trap states related to vanadium antisite on bismuth or vanadium interstitials according to density functional theory calculations. Overall, these findings provide further insights on the interplay between defect modulation and carrier transport in metal oxides, which benefit the development of low-cost, highly-efficient solar energy conversion devices.

  10. Economically sustainable: market synergies in hydrogen systems

    International Nuclear Information System (INIS)

    Hart, D.

    2000-01-01

    As interest in the use of hydrogen as an energy carrier grows, it is important to understand the advantages and disadvantages of a market-based approach to its introduction. While there will always be niche markets in which it makes sense to employ what is currently a comparatively expensive form of energy storage and delivery, this will not enable the sort of large-scale penetration that will allow for economies of mass-manufacture to bring the cost of hydrogen down. In addition, energy markets are becoming increasingly liberalised, and because of this it is important to understand the sort of market pressures that are arising where none have existed before. These pressures may actually lead to opportunities for hydrogen in energy storage and for use in power generation and transport fuel modes, and allow market penetration to occur more rapidly than might be the case in a centralised energy structure. In the liberalised energy market within the UK, for example, there are two areas of potentially major growth in hydrogen production and consumption: energy storage for renewable generators; and backup systems at weak electricity grid links. The first of these is due, in part, to potential changes in regulation governing the way that electricity is sold into the market, while the second is dependent more on an increasingly congested electricity grid and the high costs of building supplementary infrastructure. In both cases there is potential for the early use of hydrogen energy systems in an economically competitive environment. (author)

  11. Low-complexity Joint Sub-carrier Phase Noise Compensation for Digital Multi-carrier Systems

    DEFF Research Database (Denmark)

    Yankov, Metodi Plamenov; Barletta, Luca; Zibar, Darko

    2017-01-01

    Joint sub-carrier phase noise processing is proposed which recovers the SNR penalty related to decreased sub-carrier baudrate w.r.t. single carrier systems. The method enables digital sub-banding to be safely employed for nonlinear mitigation for modulation formats of up to 256-QAM.......Joint sub-carrier phase noise processing is proposed which recovers the SNR penalty related to decreased sub-carrier baudrate w.r.t. single carrier systems. The method enables digital sub-banding to be safely employed for nonlinear mitigation for modulation formats of up to 256-QAM....

  12. Sodium tetra-hydro-borate as energy/hydrogen carrier, its history

    International Nuclear Information System (INIS)

    Demirci, U.B.; Miele, Ph.

    2009-01-01

    Sodium tetra-hydro-borate NaBH 4 is considered as being a promising energy/hydrogen carrier. NaBH 4 is not a new compound. It has been discovered in 1940's by Prof. H.C. Brown, Nobel Laureate in Chemistry in 1979. NaBH 4 has thus a history and this history distinguishes the NaBH 4 utilisation as hydrogen carrier from that as energy carrier. In fact, the history of NaBH 4 (for both utilizations) can be divided into three periods, each period being characterised by specific societal challenges. Whereas during the first period the challenges were military and political, the challenges in the third period (i.e. at present) are energetic, environmental, civilian, social and political. The second period was rather calm for NaBH 4 even if it was intensively used as a reducing agent in organic chemistry. (authors)

  13. Performance of Uplink Carrier Aggregation in LTE-Advanced Systems

    DEFF Research Database (Denmark)

    Wang, Hua; Rosa, Claudio; Pedersen, Klaus

    2010-01-01

    Carrier aggregation (CA) has been proposed to aggregate two or more component carriers (CCs) to support a much wider transmission bandwidth for LTE-Advanced systems. With carrier aggregation, it is possible to schedule a user equipment (UE) on multiple component carriers simultaneously. In this p...

  14. Thermodynamic evaluation of hydrogen production for fuel cells by using bio-ethanol steam reforming: Effect of carrier gas addition

    Science.gov (United States)

    Hernández, Liliana; Kafarov, Viatcheslav

    Omitting the influence of the addition of carrier gas to the reaction system for hydrogen production by bio-ethanol steam reforming can lead to wrong conclusions, especially when it is going to be made to scale. The effect of carrier gas addition to produce hydrogen using bio-ethanol steam reforming to feed fuel cells was evaluated. Thermodynamic calculations in equilibrium conditions were made, however the analysis derived from them can also be applied to kinetic conditions. These calculations were made by using the Aspen-HYSYS software at atmospheric pressure and different values of temperature, water/ethanol molar ratios, and inert (argon)/(water/ethanol) molar ratios. The addition of inert carrier gas modifies the concentrations of the reaction products in comparison to those obtained without its presence. This behavior occurs because most of the reactions which take place in bio-ethanol steam reforming have a positive difference of moles. This fact enhances the system sensitivity to inert concentration at low and moderated temperatures (<700 °C). At high values of temperature, the inert addition does not influence the composition of the reaction products because of the predominant effect of inverse WGS reaction.

  15. Thermodynamic evaluation of hydrogen production for fuel cells by using bio-ethanol steam reforming: Effect of carrier gas addition

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, Liliana; Kafarov, Viatcheslav [Universidad Industrial de Santander, Escuela de Ingenieria Quimica, Bucaramanga 678 (Colombia)

    2009-07-01

    Omitting the influence of the addition of carrier gas to the reaction system for hydrogen production by bio-ethanol steam reforming can lead to wrong conclusions, especially when it is going to be made to scale. The effect of carrier gas addition to produce hydrogen using bio-ethanol steam reforming to feed fuel cells was evaluated. Thermodynamic calculations in equilibrium conditions were made, however the analysis derived from them can also be applied to kinetic conditions. These calculations were made by using the Aspen-HYSYS software at atmospheric pressure and different values of temperature, water/ethanol molar ratios, and inert (argon)/(water/ethanol) molar ratios. The addition of inert carrier gas modifies the concentrations of the reaction products in comparison to those obtained without its presence. This behavior occurs because most of the reactions which take place in bio-ethanol steam reforming have a positive difference of moles. This fact enhances the system sensitivity to inert concentration at low and moderated temperatures (<700 C). At high values of temperature, the inert addition does not influence the composition of the reaction products because of the predominant effect of inverse WGS reaction. (author)

  16. Assessment of the potential future market in Sweden for hydrogen as an energy carrier

    Science.gov (United States)

    Carleson, G.

    Future hydrogen markets for the period 1980-2025 are projected, the probable range of hydrogen production costs for various manufacturing methods is estimated, and expected market shares in competition with alternative energy carriers are evaluated. A general scenario for economic and industrial development in Sweden for the given period was evaluated, showing the average increase in gross national product to become 1.6% per year. Three different energy scenarios were then developed: alternatives were based on nuclear energy, renewable indigenous energy sources, and the present energy situation with free access to imported natural or synthetic fuels. An analysis was made within each scenario of the competitiveness of hydrogen on both the demand and the supply of the following sectors: chemical industry, steel industry, peak power production, residential and commercial heating, and transportation. Costs were calculated for the production, storage and transmission of hydrogen according to technically feasible methods and were compared to those of alternative energy carriers. Health, environmental and societal implications were also considered. The market penetration of hydrogen in each sector was estimated, and the required investment capital was shown to be less than 4% of the national gross investment sum.

  17. Solid lipid nanoparticles: A drug carrier system

    Directory of Open Access Journals (Sweden)

    Rashmi R Kokardekar

    2011-01-01

    Full Text Available Solid lipid nanoparticles (SLN are a type of nanoparticles. They are submicron colloidal carriers which are composed of physiological lipids, dispersed in water or in aqueous surfactant solutions. SLN have wide range of advantages over other types of nanoparticles. These include availability of large-scale production methods and no signs of cytotoxicity, which are main hindrances in the application of other types of nanoparticles. Hot and cold homogenization techniques are mainly employed for its production. They are mainly evaluated on the basis of their drug release profile and particle internal structure. The products based on SLN are under development. They have a very wide range of applications in cosmetics and pharmaceuticals. They can be applied for any purpose, for which nanoparticles have a distinct advantage. Thus, SLN can be used extensively as an alternative to the existing drug carrier systems, providing more flexibility with respect to the area of applications and also aspects for commercialization.

  18. Renewable Hydrogen Carrier — Carbohydrate: Constructing the Carbon-Neutral Carbohydrate Economy

    Directory of Open Access Journals (Sweden)

    Y.-H. Percival Zhang

    2011-01-01

    Full Text Available The hydrogen economy presents an appealing energy future but its implementation must solve numerous problems ranging from low-cost sustainable production, high-density storage, costly infrastructure, to eliminating safety concern. The use of renewable carbohydrate as a high-density hydrogen carrier and energy source for hydrogen production is possible due to emerging cell-free synthetic biology technology—cell-free synthetic pathway biotransformation (SyPaB. Assembly of numerous enzymes and co-enzymes in vitro can create complicated set of biological reactions or pathways that microorganisms or catalysts cannot complete, for example, C6H10O5 (aq + 7 H2O (l à 12 H2 (g + 6 CO2 (g (PLoS One 2007, 2:e456. Thanks to 100% selectivity of enzymes, modest reaction conditions, and high-purity of generated hydrogen, carbohydrate is a promising hydrogen carrier for end users. Gravimetric density of carbohydrate is 14.8 H2 mass% if water can be recycled from proton exchange membrane fuel cells or 8.33% H2 mass% without water recycling. Renewable carbohydrate can be isolated from plant biomass or would be produced from a combination of solar electricity/hydrogen and carbon dioxide fixation mediated by high-efficiency artificial photosynthesis mediated by SyPaB. The construction of this carbon-neutral carbohydrate economy would address numerous sustainability challenges, such as electricity and hydrogen storage, CO2 fixation and long-term storage, water conservation, transportation fuel production, plus feed and food production.

  19. Research on hydrogen production system

    International Nuclear Information System (INIS)

    Nakagiri, Toshio

    2002-07-01

    Hydrogen is closely watched for environmental issues in recent years. In this research, hydrogen production systems and production techniques are widely investigated, and selected some hydrogen production process which have high validity for FBR system. Conclusions of the investigation are shown below. (1) Water-electrolysis processes and steam reform processes at low temperatures are already realized in other fields, so they well be easily adopted for FBR system. FBR system has no advantage when compared with other systems, because water-electrolysis processes can be adopted for other electricity generation system. On the other hand, FBR system has an advantage when steam reforming processes at low temperatures will be adopted, because steam reforming processes at 550-600degC can't be adopted for LWR. (2) Thermochemical processes will be able to adopted for FBR when process temperature will be lowered and material problems solved, because their efficiencies are expected high. Radiolysis processes which use ray (for example, gamma rya) emitted in reactor can be generate hydrogen easily, so they will be able to be adopted for FBR if splitting efficiency will be higher. Further investigation and R and D to realize these processes are considered necessary. (author)

  20. Fuel cell using a hydrogen generation system

    Science.gov (United States)

    Dentinger, Paul M.; Crowell, Jeffrey A. W.

    2010-10-19

    A system is described for storing and generating hydrogen and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

  1. Hawaiian hydrogen mass transit system

    International Nuclear Information System (INIS)

    Russell, G.W.; Russell, A.

    1990-01-01

    This paper proposes a joint effort between the scientific and business communities; to create, make and have hydrogen fuel become the primary fuel of the future. Hawaii has abundant, unharnessed renewable resources yet imports almost all of its fuel. Initiating hydrogen production and industrial application in conjunction with a prototype pilot project such as this mass transit system would not only accomplish the joining of science and business but give an environmentally safe energy alternative to the state and people of Hawaii and hopefully the world

  2. Nickel Hydrogen Battery Expert System

    Science.gov (United States)

    Johnson, Yvette B.; Mccall, Kurt E.

    1992-01-01

    The Nickel Cadmium Battery Expert System-2, or 'NICBES-2', which was used by the NASA HST six-battery testbed, was subsequently converted into the Nickel Hydrogen Battery Expert System, or 'NICHES'. Accounts are presently given of this conversion process and future uses being contemplated for NICHES. NICHES will calculate orbital summary data at the end of each orbit, and store these files for trend analyses and rules-generation.

  3. Estimating Motor Carrier Management Information System Crash File Underreporting from Carrier Records.

    Science.gov (United States)

    2017-08-01

    This FMCSA-sponsored research investigated the claim that motor carriers have a substantial number of crashes in their own records that are not contained in the Motor Carrier Management Information System (MCMIS) crash file. Based on the results of t...

  4. Experimental study of temperature sensor for an ocean-going liquid hydrogen (LH2) carrier

    Science.gov (United States)

    Nakano, A.; Shimazaki, T.; Sekiya, M.; Shiozawa, H.; Aoyagi, A.; Ohtsuka, K.; Iwakiri, T.; Mikami, Z.; Sato, M.; Kinoshita, K.; Matsuoka, T.; Takayama, Y.; Yamamoto, K.

    2018-04-01

    The prototype temperature sensors for an ocean-going liquid hydrogen (LH2) carrier were manufactured by way of trial. All of the sensors adopted Platinum 1000 (PT-1000) resistance thermometer elements. Various configurations of preproduction temperature sensors were tested in AIST's LH2 test facility. In the experiments, a PT-1000 resistance thermometer, calibrated at the National Metrology Institute of Japan at AIST, was used as the standard thermometer. The temperatures measured by the preproduction sensors were compared with the temperatures measured by the standard thermometer, and the measurement accuracy of the temperature sensors in LH2 was investigated and discussed. It was confirmed that the measurement accuracies of the preproduction temperature sensors were within ±50 mK, which is the required measurement accuracy for a technical demonstration ocean-going LH2 carrier.

  5. Hydrogen fuel cell power system

    International Nuclear Information System (INIS)

    Lam, A.W.

    2004-01-01

    'Full text:' Batteries are typically a necessary and prime component of any DC power system, providing a source of on-demand stored energy with proven reliability. The integration of batteries and basic fuel cells for mobile and stationary utility applications poses a new challenge. For high value applications, the specification and operating requirements for this hybrid module differ from conventional requirements as the module must withstand extreme weather conditions and provide extreme reliability. As an electric utility company, BCHydro has embarked in the development and application of a Hydrogen Fuel Cell Power Supply (HFCPS) for field trial. A Proton Exchange Membrane (PEM)- type fuel cell including power electronic modules are mounted in a standard 19-inch rack that provides 48V, 24V, 12V DC and 120V AC outputs. The hydrogen supply consists of hydrogen bottles and regulating devices to provide a continuous fuel source to the power modules. Many tests and evaluations have been done to ensure the HFCPS package is robust and suitable for electric utility grade operation. A field trial demonstrating this standalone system addressed reliability, durability, and installation concerns as well as developed the overall system operating procedures. (author)

  6. Oxygen-hydrogen recombination system

    International Nuclear Information System (INIS)

    Sato, Shuichiro; Takejima, Masaki.

    1981-01-01

    Purpose: To avoid reduction in the performance of catalyst used for an oxygen-hydrogen recombiner in the off gas processing system of a nuclear reactor. Constitution: A thermometer is provided for the detection of temperature in an oxygen-hydrogen recombiner. A cooling pipe is provided in the recombiner and cooling medium is introduced externally. The cooling medium may be water or air. In accordance with the detection value from the thermometer, ON-OFF control is carried out for a valve to control the flow rate of the cooling medium thereby rendering the temperature in the recombiner to a predetermined value. This can prevent the catalyst from being exposed to high temperature and avoid the reduction in the performance of the catalyst. (Ikeda, J.)

  7. Solar based hydrogen production systems

    CERN Document Server

    Dincer, Ibrahim

    2013-01-01

    This book provides a comprehensive analysis of various solar based hydrogen production systems. The book covers first-law (energy based) and second-law (exergy based) efficiencies and provides a comprehensive understanding of their implications. It will help minimize the widespread misuse of efficiencies among students and researchers in energy field by using an intuitive and unified approach for defining efficiencies. The book gives a clear understanding of the sustainability and environmental impact analysis of the above systems. The book will be particularly useful for a clear understanding

  8. Safety considerations for compressed hydrogen storage systems

    International Nuclear Information System (INIS)

    Gleason, D.

    2006-01-01

    An overview of the safety considerations for various hydrogen storage options, including stationary, vehicle storage, and mobile refueling technologies. Indications of some of the challenges facing the industry as the demand for hydrogen fuel storage systems increases. (author)

  9. Intrinsic information carriers in combinatorial dynamical systems

    Science.gov (United States)

    Harmer, Russ; Danos, Vincent; Feret, Jérôme; Krivine, Jean; Fontana, Walter

    2010-09-01

    self-consistent descriptors of system dynamics in that their time-evolution is governed by a closed system of kinetic equations. Taken together, fragments are endogenous distinctions that matter for the dynamics of a system, which warrants viewing them as the carriers of information. Although fragments can be thought of as multisets of molecular species (an extensional view), their self-consistency suggests treating them as autonomous aspects cut off from their microscopic realization (an intensional view). Fragmentation is a seeded process that depends on the choice of observables whose dynamics one insists to describe. Different observables can cause distinct fragmentations, in effect altering the set of information carriers that govern the behavior of a system, even though nothing has changed in its microscopic constitution. In this contribution, we present a mathematical specification of fragments, but not an algorithmic implementation. We have described the latter elsewhere in rather technical terms that, although effective, were lacking an embedding into a more general conceptual framework, which we here provide.

  10. Intrinsic information carriers in combinatorial dynamical systems.

    Science.gov (United States)

    Harmer, Russ; Danos, Vincent; Feret, Jérôme; Krivine, Jean; Fontana, Walter

    2010-09-01

    self-consistent descriptors of system dynamics in that their time-evolution is governed by a closed system of kinetic equations. Taken together, fragments are endogenous distinctions that matter for the dynamics of a system, which warrants viewing them as the carriers of information. Although fragments can be thought of as multisets of molecular species (an extensional view), their self-consistency suggests treating them as autonomous aspects cut off from their microscopic realization (an intensional view). Fragmentation is a seeded process that depends on the choice of observables whose dynamics one insists to describe. Different observables can cause distinct fragmentations, in effect altering the set of information carriers that govern the behavior of a system, even though nothing has changed in its microscopic constitution. In this contribution, we present a mathematical specification of fragments, but not an algorithmic implementation. We have described the latter elsewhere in rather technical terms that, although effective, were lacking an embedding into a more general conceptual framework, which we here provide.

  11. Hydrogen as an energy carrier. Final report; Wasserstoff als Energietraeger. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Rebholz, H. [ed.

    1998-12-01

    This final report of the Special Field of Research 270 (SFB 270) documents the work and results of the four promotion phases from 1989 to 1998, presented in reports on 15 part-projects. From its inception, SFB 270, which bears the title ''Hydrogen as an Energy Carrier'', has been dedicated to two fields of work: in Project Area A to the production of hydrogen (7 part-projects) and in Project Area B to the transport and storage of hydrogen (8 part-projects). The scientific results of the part-projects have also been presented in detail in the progress reports and interim reports of 1991, 1994 and 1997. Some of them have also been presented at the colloquiums of SFB 270. Twelve part-projects have been abstracted individually for the ENERGY database. [German] Der vorliegende Abschlussbericht des Sonderforschungsbereichs 270 dokumentiert die Arbeiten und Ergebnisse der vier Foerderungsphasen von 1989 bis 1998. Sie sind in den Berichten von 15 Teilprojekten wiedergegeben. Der Sonderforschungsbereich 270 'Wasserstoff als Energietraeger' hat sich von Anfang an zwei Aufgabengebieten gewidmet: Im Projektbereich A der Herstellung von Wasserstoff (7 Teilprojekte) und im Projektbereich B dem Transport und der Speicherung von Wasserstoff (8 Teilprojekte). Wissenschaftliche Ergebnisse der Teilprojekte sind ausfuehrlich auch in den Arbeits- und Ergebnisberichten 1991, 1994 und 1997 wiedergegeben. Sie wurden auch, in Teilen, in entsprechenden Kolloquien des SFB 270 praesentiert. Fuer die Datenbank ENERGY wurden 12 Teilprojekte separat aufgenommen. (orig.)

  12. What is required to make hydrogen a real energy carrier option?

    Energy Technology Data Exchange (ETDEWEB)

    Braeuninger, S.; Schindler, G.; Schwab, E.; Weck, A. [BASF SE, Ludwigshafen (Germany)

    2010-12-30

    The driver for the introduction of hydrogen as mobile energy-carrier is regulatory measures to avoid the CO{sub 2} emissions which are related to the current fossil carbon based situation. H{sub 2} is a large volume chemical product with an annual production of about 45 million tons, most of which currently is also derived from fossil sources. The German transport sector consumes 2,6.10{sup 12} MJ/a which in terms of energy is equivalent to nearly 50% of the current world hydrogen production. There is the proposal to start the ''hydrogen economy'' with ''excess H{sub 2}'' which is believed to be available as inadvertently occurring byproduct of chemical processes. A potential {proportional_to}2 million tons is estimated for this ''excess H{sub 2}'' in Europe; the proposal however does not take into account, that current uses of this H{sub 2} would have to be substituted. Therefore, an overall gain for the environment cannot be expected. Therefore, a sustainable hydrogen based energy scenario has to rely on new sources. Besides Biomass gasification which in terms of technology would resemble the conventional fossil based hydrogen production, the only other viable carbon-free hydrogen source is water, which has to be split into its constituting elements. The current paper is restricted to the latter path, the feasibility of the biomass approach needs to be discussed elsewhere. If hypothetically the above mentioned energy for the German transport sector would be provided by H{sub 2} from water electrolysis an electricity input of 4.10{sup 12} MJ would be needed. This number exceeds the currently installed German wind turbine capacity by a factor of 6 and even by a factor of 36, if the weather-based {proportional_to}16% year-round on-stream factor for onshore plants is taken into account. (orig.)

  13. Water reactive hydrogen fuel cell power system

    Science.gov (United States)

    Wallace, Andrew P; Melack, John M; Lefenfeld, Michael

    2014-01-21

    A water reactive hydrogen fueled power system includes devices and methods to combine reactant fuel materials and aqueous solutions to generate hydrogen. The generated hydrogen is converted in a fuel cell to provide electricity. The water reactive hydrogen fueled power system includes a fuel cell, a water feed tray, and a fuel cartridge to generate power for portable power electronics. The removable fuel cartridge is encompassed by the water feed tray and fuel cell. The water feed tray is refillable with water by a user. The water is then transferred from the water feed tray into a fuel cartridge to generate hydrogen for the fuel cell which then produces power for the user.

  14. 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.

  15. Hydrogen energy system in California

    International Nuclear Information System (INIS)

    Zweig, R.M.

    1995-01-01

    Results of experiences on the use of hydrogen as a clean burning fuel in California and results of the South Coast Air Quality Management district tests using hydrogen as a clean burning environmentally safe fuel are given. The results of Solar Hydrogen Projects in California and recent medical data documentation of human lung damage of patients living in air polluted urban areas are summarized

  16. The fusion-hydrogen energy system

    International Nuclear Information System (INIS)

    Williams, L.O.

    1994-01-01

    This paper will describe the structure of the system, from energy generation and hydrogen production through distribution to the end users. It will show how stationary energy users will convert to hydrogen and will outline ancillary uses of hydrogen to aid in reducing other forms of pollution. It will show that the adoption of the fusion hydrogen energy system will facilitate the use of renewable energy such as wind and solar. The development of highly efficient fuel cells for production of electricity near the user and for transportation will be outlined. The safety of the hydrogen fusion energy system is addressed. This paper will show that the combination of fusion generation combined with hydrogen distribution will provide a system capable of virtually eliminating the negative impact on the environment from the use of energy by humanity. In addition, implementation of the energy system will provide techniques and tools that can ameliorate environmental problems unrelated to energy use. (Author)

  17. Analysis of Hybrid Hydrogen Systems: Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Dean, J.; Braun, R.; Munoz, D.; Penev, M.; Kinchin, C.

    2010-01-01

    Report on biomass pathways for hydrogen production and how they can be hybridized to support renewable electricity generation. Two hybrid systems were studied in detail for process feasibility and economic performance. The best-performing system was estimated to produce hydrogen at costs ($1.67/kg) within Department of Energy targets ($2.10/kg) for central biomass-derived hydrogen production while also providing value-added energy services to the electric grid.

  18. Designing Microporus Carbons for Hydrogen Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Alan C. Cooper

    2012-05-02

    An efficient, cost-effective hydrogen storage system is a key enabling technology for the widespread introduction of hydrogen fuel cells to the domestic marketplace. Air Products, an industry leader in hydrogen energy products and systems, recognized this need and responded to the DOE 'Grand Challenge' solicitation (DOE Solicitation DE-PS36-03GO93013) under Category 1 as an industry partner and steering committee member with the National Renewable Energy Laboratory (NREL) in their proposal for a center-of-excellence on Carbon-Based Hydrogen Storage Materials. This center was later renamed the Hydrogen Sorption Center of Excellence (HSCoE). Our proposal, entitled 'Designing Microporous Carbons for Hydrogen Storage Systems,' envisioned a highly synergistic 5-year program with NREL and other national laboratory and university partners.

  19. Nuclear power reactors and hydrogen storage systems

    International Nuclear Information System (INIS)

    Ibrahim Aly Mahmoud El Osery.

    1980-01-01

    Among conclusions and results come by, a nuclear-electric-hydrogen integrated power system was suggested as a way to prevent the energy crisis. It was shown that the hydrogen power system using nuclear power as a leading energy resource would hold an advantage in the current international situation as well as for the long-term future. Results reported provide designers of integrated nuclear-electric-hydrogen systems with computation models and routines which will allow them to explore the optimal solution in coupling power reactors to hydrogen producing systems, taking into account the specific characters of hydrogen storage systems. The models were meant for average computers of a type easily available in developing countries. (author)

  20. Nanostructured lipid carriers system: recent advances in drug delivery.

    Science.gov (United States)

    Iqbal, Md Asif; Md, Shadab; Sahni, Jasjeet Kaur; Baboota, Sanjula; Dang, Shweta; Ali, Javed

    2012-12-01

    Nanostructured lipid carrier (NLC) is second generation smarter drug carrier system having solid matrix at room temperature. This carrier system is made up of physiological, biodegradable and biocompatible lipid materials and surfactants and is accepted by regulatory authorities for application in different drug delivery systems. The availability of many products in the market in short span of time reveals the success story of this delivery system. Since the introduction of the first product, around 30 NLC preparations are commercially available. NLC exhibit superior advantages over other colloidal carriers viz., nanoemulsions, polymeric nanoparticles, liposomes, SLN etc. and thus, have been explored to more extent in pharmaceutical technology. The whole set of unique advantages such as enhanced drug loading capacity, prevention of drug expulsion, leads to more flexibility for modulation of drug release and makes NLC versatile delivery system for various routes of administration. The present review gives insights on the definitions and characterization of NLC as colloidal carriers including the production techniques and suitable formulations. This review paper also highlights the importance of NLC in pharmaceutical applications for the various routes of drug delivery viz., topical, oral, pulmonary, ocular and parenteral administration and its future perspective as a pharmaceutical carrier.

  1. Nickel-hydrogen bipolar battery system

    Science.gov (United States)

    Thaller, L. H.

    1982-01-01

    Rechargeable nickel-hydrogen systems are described that more closely resemble a fuel cell system than a traditional nickel-cadmium battery pack. This was stimulated by the currently emerging requirements related to large manned and unmanned low Earth orbit applications. The resultant nickel-hydrogen battery system should have a number of features that would lead to improved reliability, reduced costs as well as superior energy density and cycle lives as compared to battery systems constructed from the current state-of-the-art nickel-hydrogen individual pressure vessel cells.

  2. Modeling leaks from liquid hydrogen storage systems.

    Energy Technology Data Exchange (ETDEWEB)

    Winters, William Stanley, Jr.

    2009-01-01

    This report documents a series of models for describing intended and unintended discharges from liquid hydrogen storage systems. Typically these systems store hydrogen in the saturated state at approximately five to ten atmospheres. Some of models discussed here are equilibrium-based models that make use of the NIST thermodynamic models to specify the states of multiphase hydrogen and air-hydrogen mixtures. Two types of discharges are considered: slow leaks where hydrogen enters the ambient at atmospheric pressure and fast leaks where the hydrogen flow is usually choked and expands into the ambient through an underexpanded jet. In order to avoid the complexities of supersonic flow, a single Mach disk model is proposed for fast leaks that are choked. The velocity and state of hydrogen downstream of the Mach disk leads to a more tractable subsonic boundary condition. However, the hydrogen temperature exiting all leaks (fast or slow, from saturated liquid or saturated vapor) is approximately 20.4 K. At these temperatures, any entrained air would likely condense or even freeze leading to an air-hydrogen mixture that cannot be characterized by the REFPROP subroutines. For this reason a plug flow entrainment model is proposed to treat a short zone of initial entrainment and heating. The model predicts the quantity of entrained air required to bring the air-hydrogen mixture to a temperature of approximately 65 K at one atmosphere. At this temperature the mixture can be treated as a mixture of ideal gases and is much more amenable to modeling with Gaussian entrainment models and CFD codes. A Gaussian entrainment model is formulated to predict the trajectory and properties of a cold hydrogen jet leaking into ambient air. The model shows that similarity between two jets depends on the densimetric Froude number, density ratio and initial hydrogen concentration.

  3. Systems Analysis | Hydrogen and Fuel Cells | NREL

    Science.gov (United States)

    chain costs, sustainability metrics, and financial analyses within an optimization framework. NREL's , Handbook of Clean Energy Systems (2015) Retail Infrastructure Costs Comparison for Hydrogen and Electricity Heimiller, and Jenny Melius (2012) Infrastructure Analysis Tools: A Focus on Cash Flow Analysis, Hydrogen

  4. Electric system management through hydrogen production - A market driven approach in the French context

    International Nuclear Information System (INIS)

    Mansilla, C.; Dautremont, S.; Thais, F.; Louyrette, J.; Martin, J.; Albou, S.; Barbieri, G.; Collignon, N.; Bourasseau, C.; Salasc, B.; Valentin, S.

    2012-01-01

    Hydrogen is usually presented as a promising energy carrier that has a major role to play in low carbon transportation, through the use of fuel cells. However, such a development is not expected in the short term. In the meantime, hydrogen may also contribute to reduce carbon emissions in diverse sectors among which methanol production. Methanol can be produced by combining carbon dioxide and hydrogen, hence facilitating carbon dioxide emission mitigation while providing a beneficial tool to manage the electric system, if hydrogen is produced by alkaline electrolysis operated in a variable way driven by the spot and balancing electricity markets. Such a concept is promoted by the VItESSE project (Industrial and Energy value of CO 2 through Efficient use of CO 2 -free electricity - Electricity Network System Control and Electricity Storage). Through the proposed market driven approach, hydrogen production offers a possibility to help managing the electric system, together with an opportunity to reduce hydrogen production costs. (authors)

  5. 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

  6. [Drug delivery systems using nano-sized drug carriers].

    Science.gov (United States)

    Nakayama, Masamichi; Okano, Teruo

    2005-07-01

    Nanotechnology has attracted great attention all over the world in recent several years and has led to the establishment of the novel technical field of "nanomedicine" through collaboration with advanced medical technology. Particularly, site-specific drug targeting using particle drug carrier systems has made substantial progress and been actively developed. This review explains the essential factors (size and chemical character) of drug carriers to allow long circulation in the bloodstream avoiding the reticuloendothelial system, and shows the present status and future perspective of several types of nano-carrier systems (water-soluble polymer, liposome and polymeric micelle). We also introduce the novel concept of multi-targeting system (combination of two or more targeting methodologies) for ideal drug therapies.

  7. Cryogenic system for liquid hydrogen polarimeter

    International Nuclear Information System (INIS)

    Kitami, T.; Chiba, M.; Hirabayashi, H.; Ishii, T.; Kato, S.

    1979-01-01

    A cryogenic system has been constructed for a liquid hydrogen polarimeter in order to measure polarization of high energy proton at the 1.3 GeV electron synchrotron of Institute for Nuclear Study, University of Tokyo. The system principally consists of a cryogenerator with a cryogenic transfer line, a liquid hydrogen cryostat, and a 14.5 l target container of thin aluminum alloy where liquid hydrogen is served for the experiment. The refrigeration capacity is about 54 W at 20.4 K without a target container. (author)

  8. Overview of interstate hydrogen pipeline systems

    International Nuclear Information System (INIS)

    Gillette, J.L.; Kolpa, R.L.

    2008-01-01

    . The following discussion will focus on the similarities and differences between the two pipeline networks. Hydrogen production is currently concentrated in refining centers along the Gulf Coast and in the Farm Belt. These locations have ready access to natural gas, which is used in the steam methane reduction process to make bulk hydrogen in this country. Production centers could possibly change to lie along coastlines, rivers, lakes, or rail lines, should nuclear power or coal become a significant energy source for hydrogen production processes. Should electrolysis become a dominant process for hydrogen production, water availability would be an additional factor in the location of production facilities. Once produced, hydrogen must be transported to markets. A key obstacle to making hydrogen fuel widely available is the scale of expansion needed to serve additional markets. Developing a hydrogen transmission and distribution infrastructure would be one of the challenges to be faced if the United States is to move toward a hydrogen economy. Initial uses of hydrogen are likely to involve a variety of transmission and distribution methods. Smaller users would probably use truck transport, with the hydrogen being in either the liquid or gaseous form. Larger users, however, would likely consider using pipelines. This option would require specially constructed pipelines and the associated infrastructure. Pipeline transmission of hydrogen dates back to late 1930s. These pipelines have generally operated at less than 1,000 pounds per square inch (psi), with a good safety record. Estimates of the existing hydrogen transmission system in the United States range from about 450 to 800 miles. Estimates for Europe range from about 700 to 1,100 miles (Mohipour et al. 2004; Amos 1998). These seemingly large ranges result from using differing criteria in determining pipeline distances. For example, some analysts consider only pipelines above a certain diameter as transmission lines

  9. Overview of interstate hydrogen pipeline systems.

    Energy Technology Data Exchange (ETDEWEB)

    Gillette, J .L.; Kolpa, R. L

    2008-02-01

    . The following discussion will focus on the similarities and differences between the two pipeline networks. Hydrogen production is currently concentrated in refining centers along the Gulf Coast and in the Farm Belt. These locations have ready access to natural gas, which is used in the steam methane reduction process to make bulk hydrogen in this country. Production centers could possibly change to lie along coastlines, rivers, lakes, or rail lines, should nuclear power or coal become a significant energy source for hydrogen production processes. Should electrolysis become a dominant process for hydrogen production, water availability would be an additional factor in the location of production facilities. Once produced, hydrogen must be transported to markets. A key obstacle to making hydrogen fuel widely available is the scale of expansion needed to serve additional markets. Developing a hydrogen transmission and distribution infrastructure would be one of the challenges to be faced if the United States is to move toward a hydrogen economy. Initial uses of hydrogen are likely to involve a variety of transmission and distribution methods. Smaller users would probably use truck transport, with the hydrogen being in either the liquid or gaseous form. Larger users, however, would likely consider using pipelines. This option would require specially constructed pipelines and the associated infrastructure. Pipeline transmission of hydrogen dates back to late 1930s. These pipelines have generally operated at less than 1,000 pounds per square inch (psi), with a good safety record. Estimates of the existing hydrogen transmission system in the United States range from about 450 to 800 miles. Estimates for Europe range from about 700 to 1,100 miles (Mohipour et al. 2004; Amos 1998). These seemingly large ranges result from using differing criteria in determining pipeline distances. For example, some analysts consider only pipelines above a certain diameter as transmission lines

  10. Safe Detection System for Hydrogen Leaks

    Energy Technology Data Exchange (ETDEWEB)

    Lieberman, Robert A. [Intelligent Optical Systems, Inc., Torrance, CA (United States); Beshay, Manal [Intelligent Optical Systems, Inc., Torrance, CA (United States)

    2012-02-29

    Hydrogen is an "environmentally friendly" fuel for future transportation and other applications, since it produces only pure ("distilled") water when it is consumed. Thus, hydrogen-powered vehicles are beginning to proliferate, with the total number of such vehicles expected to rise to nearly 100,000 within the next few years. However, hydrogen is also an odorless, colorless, highly flammable gas. Because of this, there is an important need for hydrogen safety monitors that can warn of hazardous conditions in vehicles, storage facilities, and hydrogen production plants. To address this need, IOS has developed a unique intrinsically safe optical hydrogen sensing technology, and has embodied it in detector systems specifically developed for safety applications. The challenge of using light to detect a colorless substance was met by creating chemically-sensitized optical materials whose color changes in the presence of hydrogen. This reversible reaction provides a sensitive, reliable, way of detecting hydrogen and measuring its concentration using light from low-cost LEDs. Hydrogen sensors based on this material were developed in three completely different optical formats: point sensors ("optrodes"), integrated optic sensors ("optical chips"), and optical fibers ("distributed sensors") whose entire length responds to hydrogen. After comparing performance, cost, time-to-market, and relative market need for these sensor types, the project focused on designing a compact optrode-based single-point hydrogen safety monitor. The project ended with the fabrication of fifteen prototype units, and the selection of two specific markets: fuel cell enclosure monitoring, and refueling/storage safety. Final testing and development of control software for these markets await future support.

  11. Hydrogen at the Rooftop: Compact CPV-Hydrogen system to Convert Sunlight to Hydrogen

    KAUST Repository

    Burhan, Muhammad

    2017-12-27

    Despite being highest potential energy source, solar intermittency and low power density make it difficult for solar energy to compete with the conventional power plants. Highly efficient concentrated photovoltaic (CPV) system provides best technology to be paired with the electrolytic hydrogen production, as a sustainable energy source with long term energy storage. However, the conventional gigantic design of CPV system limits its market and application to the open desert fields without any rooftop installation scope, unlike conventional PV. This makes CPV less popular among solar energy customers. This paper discusses the development of compact CPV-Hydrogen system for the rooftop application in the urban region. The in-house built compact CPV system works with hybrid solar tracking of 0.1° accuracy, ensured through proposed double lens collimator based solar tracking sensor. With PEM based electrolyser, the compact CPV-hydrogen system showed 28% CPV efficiency and 18% sunlight to hydrogen (STH) efficiency, for rooftop operation in tropical region of Singapore. For plant designers, the solar to hydrogen production rating of 217 kWh/kg has been presented with 15% STH daily average efficiency, recorded from the long term field operation of the system.

  12. Hydrogen at the Rooftop: Compact CPV-Hydrogen system to Convert Sunlight to Hydrogen

    KAUST Repository

    Burhan, Muhammad; Wakil Shahzad, Muhammad; Ng, Kim Choon

    2017-01-01

    Despite being highest potential energy source, solar intermittency and low power density make it difficult for solar energy to compete with the conventional power plants. Highly efficient concentrated photovoltaic (CPV) system provides best technology to be paired with the electrolytic hydrogen production, as a sustainable energy source with long term energy storage. However, the conventional gigantic design of CPV system limits its market and application to the open desert fields without any rooftop installation scope, unlike conventional PV. This makes CPV less popular among solar energy customers. This paper discusses the development of compact CPV-Hydrogen system for the rooftop application in the urban region. The in-house built compact CPV system works with hybrid solar tracking of 0.1° accuracy, ensured through proposed double lens collimator based solar tracking sensor. With PEM based electrolyser, the compact CPV-hydrogen system showed 28% CPV efficiency and 18% sunlight to hydrogen (STH) efficiency, for rooftop operation in tropical region of Singapore. For plant designers, the solar to hydrogen production rating of 217 kWh/kg has been presented with 15% STH daily average efficiency, recorded from the long term field operation of the system.

  13. Hydrogen Storage Technologies for Future Energy Systems.

    Science.gov (United States)

    Preuster, Patrick; Alekseev, Alexander; Wasserscheid, Peter

    2017-06-07

    Future energy systems will be determined by the increasing relevance of solar and wind energy. Crude oil and gas prices are expected to increase in the long run, and penalties for CO 2 emissions will become a relevant economic factor. Solar- and wind-powered electricity will become significantly cheaper, such that hydrogen produced from electrolysis will be competitively priced against hydrogen manufactured from natural gas. However, to handle the unsteadiness of system input from fluctuating energy sources, energy storage technologies that cover the full scale of power (in megawatts) and energy storage amounts (in megawatt hours) are required. Hydrogen, in particular, is a promising secondary energy vector for storing, transporting, and distributing large and very large amounts of energy at the gigawatt-hour and terawatt-hour scales. However, we also discuss energy storage at the 120-200-kWh scale, for example, for onboard hydrogen storage in fuel cell vehicles using compressed hydrogen storage. This article focuses on the characteristics and development potential of hydrogen storage technologies in light of such a changing energy system and its related challenges. Technological factors that influence the dynamics, flexibility, and operating costs of unsteady operation are therefore highlighted in particular. Moreover, the potential for using renewable hydrogen in the mobility sector, industrial production, and the heat market is discussed, as this potential may determine to a significant extent the future economic value of hydrogen storage technology as it applies to other industries. This evaluation elucidates known and well-established options for hydrogen storage and may guide the development and direction of newer, less developed technologies.

  14. Evaluation of Nuclear Hydrogen Production System

    International Nuclear Information System (INIS)

    Park, Won Seok; Park, C. K.; Park, J. K. and others

    2006-04-01

    The major objective of this work is tow-fold: one is to develop a methodology to determine the best VHTR types for the nuclear hydrogen demonstration project and the other is to evaluate the various hydrogen production methods in terms of the technical feasibility and the effectiveness for the optimization of the nuclear hydrogen system. Both top-tier requirements and design requirements have been defined for the nuclear hydrogen system. For the determination of the VHTR type, a comparative study on the reference reactors, PBR and PBR, was conducted. Based on the analytic hierarchy process (AHP) method, a systematic methodology has been developed to compare the two VHTR types. Another scheme to determine the minimum reactor power was developed as well. Regarding the hydrogen production methods, comparison indices were defined and they were applied to the IS (Iodine-Sulfur) scheme, Westinghouse process, and the, high-temperature electrolysis method. For the HTE, IS, and MMI cycle, the thermal efficiency of hydrogen production were systematically evaluated. For the IS cycle, an overall process was identified and the functionality of some key components was identified. The economy of the nuclear hydrogen was evaluated, relative to various primary energy including natural gas coal, grid-electricity, and renewable. For the international collaborations, two joint research centers were established: NH-JRC between Korea and China and NH-JDC between Korea and US. Currently, several joint researches are underway through the research centers

  15. Development of Automotive Liquid Hydrogen Storage Systems

    Science.gov (United States)

    Krainz, G.; Bartlok, G.; Bodner, P.; Casapicola, P.; Doeller, Ch.; Hofmeister, F.; Neubacher, E.; Zieger, A.

    2004-06-01

    Liquid hydrogen (LH2) takes up less storage volume than gas but requires cryogenic vessels. State-of-the-art applications for passenger vehicles consist of double-wall cylindrical tanks that hold a hydrogen storage mass of up to 10 kg. The preferred shell material of the tanks is stainless steel, since it is very resistant against hydrogen brittleness and shows negligible hydrogen permeation. Therefore, the weight of the whole tank system including valves and heat exchanger is more than 100 kg. The space between the inner and outer vessel is mainly used for thermal super-insulation purposes. Several layers of insulation foils and high vacuums of 10-3 Pa reduce the heat entry. The support structures, which keep the inner tank in position to the outer tank, are made of materials with low thermal conductivity, e.g. glass or carbon fiber reinforced plastics. The remaining heat in-leak leads to a boil-off rate of 1 to 3 percent per day. Active cooling systems to increase the stand-by time before evaporation losses occur are being studied. Currently, the production of several liquid hydrogen tanks that fulfill the draft of regulations of the European Integrated Hydrogen Project (EIHP) is being prepared. New concepts of lightweight liquid hydrogen storage tanks will be investigated.

  16. Hydrogen storage and delivery system development: Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Handrock, J.L. [Sandia National Labs., Livermore, CA (United States)

    1996-10-01

    Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Results of the analytical model development portion of this project will be discussed. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a recently developed fuel cell vehicle storage system model will also be discussed. As an example of model use, power distribution and control for a simulated driving cycle is presented. Model calibration results of fuel cell fluid inlet and exit temperatures at various fuel cell idle speeds, assumed fuel cell heat capacities, and ambient temperatures are presented. The model predicts general increases in temperature with fuel cell power and differences between inlet and exit temperatures, but under predicts absolute temperature values, especially at higher power levels.

  17. Future hydrogen markets for large-scale hydrogen production systems

    International Nuclear Information System (INIS)

    Forsberg, Charles W.

    2007-01-01

    The cost of delivered hydrogen includes production, storage, and distribution. For equal production costs, large users (>10 6 m 3 /day) will favor high-volume centralized hydrogen production technologies to avoid collection costs for hydrogen from widely distributed sources. Potential hydrogen markets were examined to identify and characterize those markets that will favor large-scale hydrogen production technologies. The two high-volume centralized hydrogen production technologies are nuclear energy and fossil energy with carbon dioxide sequestration. The potential markets for these technologies are: (1) production of liquid fuels (gasoline, diesel and jet) including liquid fuels with no net greenhouse gas emissions and (2) peak electricity production. The development of high-volume centralized hydrogen production technologies requires an understanding of the markets to (1) define hydrogen production requirements (purity, pressure, volumes, need for co-product oxygen, etc.); (2) define and develop technologies to use the hydrogen, and (3) create the industrial partnerships to commercialize such technologies. (author)

  18. Adaptive Disturbance Rejection Control for Automatic Carrier Landing System

    Directory of Open Access Journals (Sweden)

    Xin Wang

    2016-01-01

    Full Text Available An adaptive disturbance rejection algorithm is proposed for carrier landing system in the final-approach. The carrier-based aircraft dynamics and the linearized longitudinal model under turbulence conditions in the final-approach are analyzed. A stable adaptive control scheme is developed based on LDU decomposition of the high-frequency gain matrix, which ensures closed-loop stability and asymptotic output tracking. Finally, simulation studies of a linearized longitudinal-directional dynamics model are conducted to demonstrate the performance of the adaptive scheme.

  19. Case Studies of integrated hydrogen systems. International Energy Agency Hydrogen Implementing Agreement, Final report for Subtask A of task 11 - Integrated Systems

    Energy Technology Data Exchange (ETDEWEB)

    Schucan, T. [Paul Scherrer Inst., Villigen PSI (Switzerland)

    1999-12-31

    Within the framework of the International Energy Agency Hydrogen Implementing Agreement, Task 11 was undertaken to develop tools to assist in the design and evaluation of existing and potential hydrogen demonstration projects. Emphasis was placed on integrated systems, from input energy to hydrogen end use. Included in the PDF document are the Executive Summary of the final report and the various case studies. The activities of task 11 were focused on near- and mid-term applications, with consideration for the transition from fossil-based systems to sustainable hydrogen energy systems. The participating countries were Canada, Italy, Japan, the Netherlands, Spain, Switzerland and the United States. In order for hydrogen to become a competitive energy carrier, experience and operating data need to be generated and collected through demonstration projects. A framework of scientific principles, technical expertise, and analytical evaluation and assessment needed to be developed to aid in the design and optimization of hydrogen demonstration projects to promote implementation. The task participants undertook research within the framework of three highly coordinated subtasks that focused on the collection and critical evaluation of data from existing demonstration projects around the world, the development and testing of computer models of hydrogen components and integrated systems, and the evaluation and comparison of hydrogen systems. While the Executive Summary reflects work on all three subtasks, this collection of chapters refers only to the work performed under Subtask A. Ten projects were analyzed and evaluated in detail as part of Subtask A, Case Studies. The projects and the project partners were: Solar Hydrogen Demonstration Project, Solar-Wasserstoff-Bayern, Bayernwerk, BMW, Linde, Siemens (Germany); Solar Hydrogen Plant on Residential House, M. Friedli (Switzerland); A.T. Stuart Renewable Energy Test Site; Stuart Energy Systems (Canada); PHOEBUS Juelich

  20. 21st Century's energy: Hydrogen energy system

    International Nuclear Information System (INIS)

    Veziroglu, T. Nejat; Sahin, Suemer

    2008-01-01

    Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the hydrogen energy system. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar-hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar-hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st century

  1. 21st century's energy: hydrogen energy system

    International Nuclear Information System (INIS)

    Veziroglu, T. N.

    2007-01-01

    Fossil fuels (i.e., petroleum, natural gas and coal), which meet most of the world's energy demand today, are being depleted fast. Also, their combustion products are causing the global problems, such as the greenhouse effect, ozone layer depletion, acid rains and pollution, which are posing great danger for our environment and eventually for the life in our planet. Many engineers and scientists agree that the solution to these global problems would be to replace the existing fossil fuel system by the Hydrogen Energy System. Hydrogen is a very efficient and clean fuel. Its combustion will produce no greenhouse gases, no ozone layer depleting chemicals, little or no acid rain ingredients and pollution. Hydrogen, produced from renewable energy (e.g., solar) sources, would result in a permanent energy system, which we would never have to change. However, there are other energy systems proposed for the post-petroleum era, such as a synthetic fossil fuel system. In this system, synthetic gasoline and synthetic natural gas will be produced using abundant deposits of coal. In a way, this will ensure the continuation of the present fossil fuel system. The two possible energy systems for the post-fossil fuel era (i.e., the solar hydrogen energy system and the synthetic fossil fuel system) are compared with the present fossil fuel system by taking into consideration production costs, environmental damages and utilization efficiencies. The results indicate that the solar hydrogen energy system is the best energy system to ascertain a sustainable future, and it should replace the fossil fuel system before the end of the 21st Century

  2. System and carrier for optical images and holographic information recording

    International Nuclear Information System (INIS)

    Andries, A.; Bivol, V.; Iovu, M

    2002-01-01

    The invention relates to the semiconducting silverless photography, in particular to the technique for optical information recording and may be used in microphotography for manifacture of microfiches, microfilms, storage disks, i the multiplication and copying technique, in holography, in micro- and optoelectronics, cinematography etc. The system for optical images and holographic information recording includes an optical exposure system, an information carrier , containing a dielectric substrate with the first electrode, a photosensitive element and the second electrode, arranged in consecutive order, a constant and impulse voltage source, a means for climbing and movement of the information carrier, a control unit for connection of the voltage source to the electroconducting strate, a personal computer, connected to the control unit of the recording modes ,to the exposure system and the information carrier, an electrooptical transparency, connected to the computer by means of the matching unit. The carrier for optical images and holographic information recording contains a dielectric substrate, a photosensitive element formed of a layer of the vitreous chalcogenic semiconductor and a layer of the crystalline or amorphous semiconductor, forming a heterojunction, the photosensitive element is arranged between two electrodes , one of which is made transparent , in such case rge layer of the vitreous chalcogenic semiconductor comes into contact with the superior transparent electrode, subjected to exposure

  3. Experimental study on steam gasification of coal using molten blast furnace slag as heat carrier for producing hydrogen-enriched syngas

    International Nuclear Information System (INIS)

    Duan, Wenjun; Yu, Qingbo; Wu, Tianwei; Yang, Fan; Qin, Qin

    2016-01-01

    Highlights: • New method for producing HRG by gasification using BFS as heat carrier was proposed. • The continuous experiment of steam gasification in molten BFS was conducted. • The hydrogen-enriched syngas was produced by this method. • The molten BFS waste heat was utilized effectively by steam gasification. • This method could be widely used in steam gasification of different types of coal. - Abstract: The new method for producing hydrogen-enriched syngas (HRG) by steam gasification of coal using molten blast furnace slag (BFS) as heat carrier was established. In order to achieve the HRG production, a gasification system using this method was proposed and constructed. The carbon gasification efficiency (CE), hydrogen yield (YH_2) and cold gasification efficiency (CGE) in the molten slag reactor were measured, and the effects of temperature, S/C (steam to coal) ratio and coal type on the reaction performance were accessed. The results indicated that the preferred temperature was 1350 °C, which ensured the miscibility of coal–steam–slag, the diffusion of reactant in molten BFS as well as recovering waste heat. The optimal S/C ratio was 1.5–2.0 for producing HRG. Under these conditions, the hydrogen fraction was higher than 63% and the gas yield reached to 1.89 Nm"3/kg. The CE and CGE were higher than 96% and 102%, respectively. The YH_2 also reached to 1.20 Nm"3/kg. Meanwhile, different types of coal were successfully gasified in molten BFS reactor for producing HRG. The proposed method enhanced the gasification efficiency of different types of coal, recovered the BFS waste heat effectively, and had important guidance for industrial manufacture.

  4. Systems analysis on the condition of market penetration for hydrogen technologies using linear programming model

    International Nuclear Information System (INIS)

    Kato, K.; Ihara, S.

    1993-01-01

    Hydrogen is expected to be an important energy carrier, especially in the frame of global warming problem solution. The purpose of this study is to examine the condition of market penetration of hydrogen technologies in reducing CO 2 emissions. A multi-time-period linear programming model (MARKAL, Market Allocation)) is used to explore technology options and cost for meeting the energy demands while reducing CO 2 emissions from energy systems. The results show that hydrogen technologies become economical when CO 2 emissions are stringently constrained. 9 figs., 2 refs

  5. Economic Dispatch of Hydrogen Systems in Energy Spot Markets

    DEFF Research Database (Denmark)

    You, Shi; Nørgård, Per Bromand

    2015-01-01

    of energy spot markets. The generic hydrogen system is comprised of an electrolysis for hydrogen production, a hydrogen storage tank and a fuel cell system for cogeneration of electricity and heat. A case study is presented with information from practical hydrogen systems and the Nordic energy markets...

  6. Novel, Ceramic Membrane System For Hydrogen Separation

    Energy Technology Data Exchange (ETDEWEB)

    Elangovan, S.

    2012-12-31

    Separation of hydrogen from coal gas represents one of the most promising ways to produce alternative sources of fuel. Ceramatec, teamed with CoorsTek and Sandia National Laboratories has developed materials technology for a pressure driven, high temperature proton-electron mixed conducting membrane system to remove hydrogen from the syngas. This system separates high purity hydrogen and isolates high pressure CO{sub 2} as the retentate, which is amenable to low cost capture and transport to storage sites. The team demonstrated a highly efficient, pressure-driven hydrogen separation membrane to generate high purity hydrogen from syngas using a novel ceramic-ceramic composite membrane. Recognizing the benefits and limitations of present membrane systems, the all-ceramic system has been developed to address the key technical challenges related to materials performance under actual operating conditions, while retaining the advantages of thermal and process compatibility offered by the ceramic membranes. The feasibility of the concept has already been demonstrated at Ceramatec. This project developed advanced materials composition for potential integration with water gas shift rectors to maximize the hydrogenproduction.

  7. Determination of hydrogen in zirconium and its alloys by melt extraction under carrier gas flow using thermal conductivity cell as detector

    International Nuclear Information System (INIS)

    Akhtar, J.; Ahmed, M.; Mohammad, B.; Jan, S.; Waqar, F.

    1987-06-01

    In the production of zirconium metal and its alloys the presence of hydrogen impurity affects mechanical and corrosion resistance properties of the product. Therefore, determination of hydrogen contents of the product is necessary. Conditions for its analysis by melt extraction under carrier gas stream using thermal conductivity cell as detector were studied and optimised. The method is capable of measuring hydrogen impurity in parts per million range. (author)

  8. The impact of large-scale energy storage requirements on the choice between electricity and hydrogen as the major energy carrier in a non-fossil renewables-only scenario

    International Nuclear Information System (INIS)

    Converse, Alvin O.

    2006-01-01

    The need for large-scale storage, when the energy source is subject to periods of low-energy generation, as it would be in a direct solar or wind energy system, could be the factor which justifies the choice of hydrogen, rather than electricity, as the principal energy carrier. It could also be the 'Achilles heel' of a solar-based sustainable energy system, tipping the choice to a nuclear breeder system

  9. 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.

  10. Solar hydrogen hybrid system with carbon storage

    International Nuclear Information System (INIS)

    Zini, G.; Marazzi, R.; Pedrazzi, S.; Tartarini, P.

    2009-01-01

    A complete solar hydrogen hybrid system has been developed to convert, store and use energy from renewable energy sources. The theoretical model has been implemented in a dynamic model-based software environment and applied to real data to simulate its functioning over a one-year period. Results are used to study system design and performance. A photovoltaic sub-system directly drives a residential load and, if a surplus of energy is available, an electrolyzer to produce hydrogen which is stored in a cluster of nitrogen-cooled tanks filled with AX-21 activated carbons. When the power converted from the sun is not sufficient to cover load needs, hydrogen is desorbed from activated carbon tanks and sent to the fuel-cell sub-system so to obtain electrical energy. A set of sub-systems (bus-bar, buck- and boost-converters, inverter, control circuits), handle the electrical power according to a Programmable Logic Control unit so that the load can be driven with adequate Quality of Service. Hydrogen storage is achieved through physisorption (weak van der Waals interactions) between carbon atoms and hydrogen molecules occurring at low temperature (77 K) in carbon porous solids at relatively low pressures. Storage modeling has been developed using a Langmuir-Freundlich 1st type isotherm and experimental data available in literature. Physisorption storage provides safer operations along with good gravimetric (10.8% at 6 MPa) and volumetric (32.5 g/l at 6 MPa) storage capacities at costs that can be comparable to, or smaller than, ordinary storage techniques (compression or liquefaction). Several test runs have been performed on residential user data-sets: the system is capable of providing grid independence and can be designed to yield a surplus production of hydrogen which can be used to recharge electric car batteries or fill tanks for non-stationary uses. (author)

  11. A windowless frozen hydrogen target system

    International Nuclear Information System (INIS)

    Knowles, P.E.; Beer, G.A.; Beveridge, J.L.

    1995-06-01

    A cryogenic target system has been constructed in which gaseous mixtures of all three hydrogen isotopes have been frozen onto a thin, 65 mm diameter gold foil. The foil is cooled to 3 K while inside a 70 K radiation shield, all of which is mounted in a vacuum system maintained at 10 -9 torr. Stable multi-layer hydrogen targets of known uniformity and thickness have been maintained for required measurement times of up to several days. To date, hundreds of targets have been successfully used in muon-catalyzed fusion experiments at TRIUMF. (author). 12 refs., 6 figs

  12. Algal Systems for Hydrogen Photoproduction

    Energy Technology Data Exchange (ETDEWEB)

    Ghirardi, Maria L [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-10-08

    The National Renewable Energy Laboratory (NREL), under the guidance of Drs. Michael Seibert (retired, Fellow Emeritus) and Maria Ghirardi (Fellow), led 15 years of research addressing the issue of algal H2 photoproduction. This project resulted in greatly increased rates and yields of algal hydrogen production; increased understanding of the H2 metabolism in the green alga, Chlamydomonas reinhardtii; expanded our knowledge of other physiological aspects relevant to sustained algal photosynthetic H2 production; led to the genetic identification, cloning and manipulation of algal hydrogenase genes; and contributed to a broader, fundamental understanding of the technical and scientific challenges to improving the conversion efficiencies in order to reach the U.S. Department of Energy’s Fuel Cell Technologies Office’s targets. Some of the tangible results are: (i) 64 publications and 6 patents, (ii) international visibility to NREL, (iii) reinvigoration of national and international biohydrogen research, and (iv) research progress that helped stimulate new funding from other DOE and non-DOE programs, including the AFOSR and the DOE Office of Science.

  13. Pyrophosphate as a central energy carrier in the hydrogen-producing extremely thermophilic Caldicellulosiruptor saccharolyticus

    NARCIS (Netherlands)

    Bielen, A.A.M.; Willquist, K.; Engman, J.; Oost, van der J.; Niel, van E.W.J.; Kengen, S.W.M.

    2010-01-01

    The role of inorganic pyrophosphate (PPi) as an energy carrier in the central metabolism of the extremely thermophilic bacterium Caldicellulosiruptor saccharolyticus was investigated. In agreement with its annotated genome sequence, cell extracts were shown to exhibit PPi-dependent

  14. Automotive dual-mode hydrogen generation system

    Science.gov (United States)

    Kelly, D. A.

    The automotive dual mode hydrogen generation system is advocated as a supplementary hydrogen fuel means along with the current metallic hydride hydrogen storage method for vehicles. This system consists of utilizing conventional electrolysis cells with the low voltage dc electrical power supplied by two electrical generating sources within the vehicle. Since the automobile engine exhaust manifold(s) are presently an untapped useful source of thermal energy, they can be employed as the heat source for a simple heat engine/generator arrangement. The second, and minor electrical generating means consists of multiple, miniature air disk generators which are mounted directly under the vehicle's hood and at other convenient locations within the engine compartment. The air disk generators are revolved at a speed which is proportionate to the vehicles forward speed and do not impose a drag on the vehicles motion.

  15. A comparative study of ammonia energy systems as a future energy carrier, with particular reference to vehicle use in Japan

    International Nuclear Information System (INIS)

    Miura, Daisuke; Tezuka, Tetsuo

    2014-01-01

    The choice of secondary energy carriers, such as electricity, hydrogen and ammonia, influences not only economic and environmental performances but also the reliability of an entire energy system. This article focuses on ammonia because of its excellent property in energy storage, and assesses the relative advantages of several ammonia energy systems for vehicle use in Japan by estimating energy efficiency, CO 2 emissions, and the supply cost of several ammonia energy paths, which are then compared with alternative paths using different energy carriers including hydrogen and electricity. The article also discusses inherent merits and challenges of ammonia energy systems and identifies directions for future research and development. Using ammonia as an energy carrier was demonstrated to be competitive in terms of efficiency, CO 2 emissions and supply cost for energy systems requiring fairly large numbers of storage days. This assessment shows that the use of ammonia in an energy system can improve the continuity of the energy supply in a country or region with insecurity of supply. On the other hand, we argue that further technical improvements and cost reduction associated with both conventional and unconventional ammonia production is imperative for using ammonia in a normal energy system. - Highlights: • We assess merits of energy supply systems using ammonia as an energy carrier. • Comparison with hydrogen or electricity-based energy systems was carried out. • We find ammonia is competitive when requiring large numbers of storage days. • The use of ammonia in energy systems can improve the continuity of energy supply. • Technical improvements are needed to make ammonia attractive in normal systems

  16. Effect of hydrogen on change carrier dissipation in 60Co irradiated by γ-quanta and non-alloyed n-type GaAs

    International Nuclear Information System (INIS)

    Korshunov, F.P.; Kurilovich, N.F.; Prokhorenko, T.A.; Shesholko, V.K.; Bumaj, Yu.A.

    2001-01-01

    The pretreatment in hydrogen plasma (the hydrogenation) influences on the charge carrier dissipation processes in the non-alloyed gallium arsenide of n-type with no = (5...7) centre dot 10 15 cm -3 and μo = (5...6) centre dot 10 13 cm 2 / (V centre dot c) irradiated by γ-quantum 60 Co was studied. The comparison of experimental dependence μ (T) with the designed one in the temperature range 77...291 K for non-hydrogenized and hydrogenized non irradiated and γ-quantum irradiated crystals was carried out. It is shown that the main dissipative mechanism that determine the charged carrier mobility in the non hydrogenized material is the dissipation on the charged centers - the radiation defects in the γ-quantum irradiated GaAs; the presence of double ionized defects is possible

  17. The equilibrium hydrogen pressure-temperature diagram for the liquid sodium-hydrogen-oxygen system

    International Nuclear Information System (INIS)

    Knights, C.F.; Whittingham, A.C.

    1982-01-01

    The underlying equilibria in the sodium-hydrogen-oxygen system are presented in the form of a completmentary hydrogen equilibrium pressure-temperature diagram, constructed by using published data and supplemented by experimental measurements of hydrogen equilibrium pressures over condensed phases in the system. Possible applications of the equilibrium pressure-temperature phase diagram limitations regarding its use are outlined

  18. Renewable Hydrogen Carrier - Carbohydrate: Constructing the Carbon-Neutral Carbohydrate Economy

    Science.gov (United States)

    2011-01-31

    combinations have been investigated for the production of hydrogen from biomass carbohydrate. Chemical catalysis approaches include pyrolysis [19...temperature. High fructose corn syrup, low-cost sucrose replacement, is made by stabilized glucose isomerase, which can work at ~60 °C for even about two...gasoline, vegetable oil vs. biodiesel, corn kernels vs. ethanol [31,109]. Given a price of $0.18/kg carbohydrate (i.e., $10.6/GJ) [2,44], the hydrogen

  19. The Palm Desert renewable [hydrogen] transportation system

    Energy Technology Data Exchange (ETDEWEB)

    Chamberlin, C.E.; Lehman, P. [Humboldt State Univ., Arcata, CA (United States). Schatz Energy Research Center

    1998-08-01

    This paper describes the Schatz Energy Research Center (SERC) progress on the Palm Desert Renewable Hydrogen Transportation System Project for the period June 1997 through May 1998. The project began in March 1996. The goal of the Palm Desert Project is to develop a clean and sustainable transportation system for a community. The project demonstrates the practical utility of hydrogen as a transportation fuel and the proton exchange membrane (PEM) fuel cell as a vehicle power system. The project includes designing and building 4 fuel cell powered vehicles, a solar hydrogen generating and refueling station, and a fuel cell vehicle diagnostic center. Over this last year, SERC has built a fuel cell powered neighborhood electric vehicle and delivered it to the City of Palm Desert. The design of the hydrogen refueling station is near completion and it is anticipated that construction will be complete in the fall of 1998. The vehicles are currently being refueled at a temporary refueling station. The diagnostic center is being designed and maintenance procedures as well as computer diagnostic programs for the fuel cell vehicles are being developed. City employees are driving the vehicles daily and monitoring data are being collected. The drivers are pleased with the performance of the vehicles.

  20. Hydrogen Production from Cyclic Chemical Looping Steam Methane Reforming over Yttrium Promoted Ni/SBA-16 Oxygen Carrier

    Directory of Open Access Journals (Sweden)

    Sanaz Daneshmand-Jahromi

    2017-09-01

    Full Text Available In this work, the modification of Ni/SBA-16 oxygen carrier (OC with yttrium promoter is investigated. The yttrium promoted Ni-based oxygen carrier was synthesized via co-impregnation method and applied in chemical looping steam methane reforming (CL-SMR process, which is used for the production of clean energy carrier. The reaction temperature (500–750 °C, Y loading (2.5–7.4 wt. %, steam/carbon molar ratio (1–5, Ni loading (10–30 wt. % and life time of OCs over 16 cycles at 650 °C were studied to investigate and optimize the structure of OC and process temperature with maximizing average methane conversion and hydrogen production yield. The synthesized OCs were characterized by multiples techniques. The results of X-ray powder diffraction (XRD and energy dispersive X-ray spectroscopy (EDX of reacted OCs showed that the presence of Y particles on the surface of OCs reduces the coke formation. The smaller NiO species were found for the yttrium promoted OC and therefore the distribution of Ni particles was improved. The reduction-oxidation (redox results revealed that 25Ni-2.5Y/SBA-16 OC has the highest catalytic activity of about 99.83% average CH4 conversion and 85.34% H2 production yield at reduction temperature of 650 °C with the steam to carbon molar ratio of 2.

  1. Hydrogen mitigation systems - a Canadian regulatory perspective

    International Nuclear Information System (INIS)

    Khosla, J.K.; Rizk, M.

    1997-01-01

    This is a discussion paper to examine the regulatory requirements that may be necessary for the design, operation and maintenance of the hydrogen mitigation systems. These systems (if deemed necessary to maintain the containment function), may be considered to be a part of the containment systems. Therefore, these requirements are derived mostly from the AECB Regulatory Document R-7, which specifies the requirements for containment systems for CANDU nuclear power plants. Some additional requirements, which are specific to these systems have also been included. These requirements relate to a systematic examination of the hazards of hydrogen, the design basis for the mitigation systems, their functional and design requirements, analytical support to justify their selection, and operating and testing requirements. The requirements for severe accident have not yet been developed. It is, however, anticipated that the design of the hydrogen mitigation system would be such that future requirement can be accommodated. These requirements are intended for application to the new reactors in Canada. For the existing reactors, their application will be subjected to practicability. (author)

  2. Development of nickel hydrogen battery expert system

    Science.gov (United States)

    Shiva, Sajjan G.

    1990-01-01

    The Hubble Telescope Battery Testbed employs the nickel-cadmium battery expert system (NICBES-2) which supports the evaluation of performances of Hubble Telescope spacecraft batteries and provides alarm diagnosis and action advice. NICBES-2 also provides a reasoning system along with a battery domain knowledge base to achieve this battery health management function. An effort to modify NICBES-2 to accommodate nickel-hydrogen battery environment in testbed is described.

  3. Estimating motor carrier management information system crash file underreporting from carrier records : research brief.

    Science.gov (United States)

    2017-08-01

    This study estimated a significant amount of underreporting to the MCMIS crash file by the States, for the carriers who cooperated in the study. For the study carriers, it appears that the MCMIS file contained about 66 percent of their reportable cra...

  4. Seasonal energy storage - PV-hydrogen systems

    Energy Technology Data Exchange (ETDEWEB)

    Leppaenen, J. [Neste Oy/NAPS (Finland)

    1998-10-01

    PV systems are widely used in remote areas e.g. in telecommunication systems. Typically lead acid batteries are used as energy storage. In northern locations seasonal storage is needed, which however is too expensive and difficult to realise with batteries. Therefore, a PV- battery system with a diesel backup is sometimes used. The disadvantages of this kind of system for very remote applications are the need of maintenance and the need to supply the fuel. To overcome these problems, it has been suggested to use hydrogen technologies to make a closed loop autonomous energy storage system

  5. Conception of modular hydrogen storage systems for portable applications

    International Nuclear Information System (INIS)

    Paladini, V.; Miotti, P.; Manzoni, G.; Ozebec, J.

    2003-01-01

    Hydrogen, till now the most prominent candidate as a future sustainable energy carrier, yields a gravimetric energy density three times as high as liquid hydrocarbon. Furthermore it is proven to be the most environmentally friendly fuel. Unfortunately, a few components regarding storage and tank solutions have not yet reached a technology level required for broad use. Thus, we intend to propose solutions and device concepts for both devices everyday use and space applications. This contribution assesses both state of the art of storage materials and existing technologies of power generation systems for application in portable devices. The aim of this work is to define the characteristics of a modular system, being suitable for a wide range of different devices, operating on advanced metal hydrides as the active hydrogen supply component. The concept has been studied and modelled with respect to volumes, mass and power requirements of different devices. The smallest system developed is intended to run, for example, a mobile phone. Minor tuning and straightforward scale up of this power supply module should make it suitable for general applicability in any portable device. (author)

  6. Long term hydrogen production potential of concentrated photovoltaic (CPV) system in tropical weather of Singapore

    KAUST Repository

    Burhan, Muhammad

    2016-08-23

    Concentrated photovoltaic (CPV) system provides highest solar energy conversion efficiency among all the photovoltaic technologies and provides the most suitable option to convert solar energy into hydrogen, as future sustainable energy carrier. So far, only conventional flat plate PV systems are being used for almost all of the commercial applications. However, most of the studies have only shown the maximum efficiency of hydrogen production using CPV. In actual field conditions, the performance of CPV-Hydrogen system is affected by many parameter and it changes continuously during whole day operation. In this paper, the daily average and long term performances are proposed to analyze the real field potential of the CPV-Hydrogen system, which is of main interest for designers and consumers. An experimental setup is developed and a performance model is proposed to investigate the average and long term production potential of CPV-Hydrogen system. The study is carried out in tropical weather of Singapore. The maximum CPV efficiency of 27-28% and solar to hydrogen (STH) efficiency of 18%, were recorded. In addition, the CPV-Hydrogen system showed the long term average efficiency of 15.5%, for period of one year (12-months), with electrolyser rating of 47 kWh/kg and STH production potential of 218 kWh/kg. Based upon the DNI availability, the system showed hydrogen production potential of 0.153-0.553 kg/m/month, with average production of 0.43 kg/m/month. However, CPV-Hydrogen system has shown annual hydrogen production potential of 5.162 kg/m/year in tropical weather of Singapore.

  7. 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

  8. FY17 Transportation and Hydrogen Systems Center Journal Publication Highlights

    Energy Technology Data Exchange (ETDEWEB)

    2017-12-08

    NREL's Transportation and Hydrogen Systems Center published 39 journal articles in fiscal year 2017 highlighting recent research in advanced vehicle technology, alternative fuels, and hydrogen systems.

  9. Socio-cultural barriers to the development of a sustainable energy system - the case of hydrogen

    DEFF Research Database (Denmark)

    Petersen, Lars Kjerulf; Andersen, Anne Holst

    Any transition to a more sustainable energy system, radically reducing greenhouse gas emissions, is bound to run in to a host of different barriers - technological and economic, but also socio-cultural. This will also be the case for any large-scale application of hydrogen as energy carrier......, especially if the system is going to be based on renewable energy sources. The aim of these research notes is to review and discuss major socio-cultural barriers to new forms of energy supply in general and to hydrogen specifically. Reaching sufficient reductions in greenhouse gas emissions may require more...

  10. Hydrogen as Future Energy Carrier: The ENEA Point of View on Technology and Application Prospects

    Directory of Open Access Journals (Sweden)

    Marina Ronchetti

    2009-03-01

    Full Text Available Hydrogen and fuel cells should reduce costs and increase reliability and durability to compete in the energy market. A considerable long term effort is necessary for research, development and demonstration of adequate solutions; important programs in this sense are carried out in the main industrialized countries, with the involvement of many industries, research structures and stakeholders. In such framework a relevant role is played in Italy by ENEA (Italian Agency for New Technologies, Energy and Environment. In the paper the main aspects related to the possible hydrogen role in the future society are addressed, according to ENEA perspectives.

  11. Study on commercial HTGR hydrogen production system

    International Nuclear Information System (INIS)

    Nishihara, Tetsuo

    2000-07-01

    The Japanese energy demand in 2030 will increase up to 117% in comparison with one in 2000. We have to avoid a large consumption of fossil fuel that induces a large CO 2 emission from viewpoint of global warming. Furthermore new energy resources expected to resolve global warming have difficulty to be introduced more because of their low energy density. As a result, nuclear power still has a possibility of large introduction to meet the increasing energy demand. On the other hand, in Japan, 40% of fossil fuels in the primary energy are utilized for power generation, and the remaining are utilized as a heat source. New clean energy is required to reduce the consumption of fossil fuels and hydrogen is expected as a alternative energy resource. Prediction of potential hydrogen demand in Japan is carried out and it is clarified that the demand will potentially increase up to 4% of total primary energy in 2050. In present, steam reforming method is the most economical among hydrogen generation processes and the cost of hydrogen production is about 7 to 8 yen/m 3 in Europe and the United States and about 13 yen/m 3 in Japan. JAERI has proposed for using the HTGR whose maximum core outlet temperature is at 950degC as a heat source in the steam reforming to reduced the consumption of fossil fuels and resulting CO 2 emission. Based on the survey of the production rate and the required thermal energy in conventional industry, it is clarified that a hydrogen production system by the steam reforming is the best process for the commercial HTGR nuclear heat utilization. The HTGR steam reforming system and other candidate nuclear heat utilization systems are considered from viewpoint of system layout and economy. From the results, the hydrogen production cost in the HTGR stream reforming system is expected to be about 13.5 yen/m 3 if the cost of nuclear heat of the HTGR is the same as one of the LWR. (author)

  12. Final Report: Hydrogen Storage System Cost Analysis

    Energy Technology Data Exchange (ETDEWEB)

    James, Brian David [Strategic Analysis Inc., Arlington, VA (United States); Houchins, Cassidy [Strategic Analysis Inc., Arlington, VA (United States); Huya-Kouadio, Jennie Moton [Strategic Analysis Inc., Arlington, VA (United States); DeSantis, Daniel A. [Strategic Analysis Inc., Arlington, VA (United States)

    2016-09-30

    The Fuel Cell Technologies Office (FCTO) has identified hydrogen storage as a key enabling technology for advancing hydrogen and fuel cell power technologies in transportation, stationary, and portable applications. Consequently, FCTO has established targets to chart the progress of developing and demonstrating viable hydrogen storage technologies for transportation and stationary applications. This cost assessment project supports the overall FCTO goals by identifying the current technology system components, performance levels, and manufacturing/assembly techniques most likely to lead to the lowest system storage cost. Furthermore, the project forecasts the cost of these systems at a variety of annual manufacturing rates to allow comparison to the overall 2017 and “Ultimate” DOE cost targets. The cost breakdown of the system components and manufacturing steps can then be used to guide future research and development (R&D) decisions. The project was led by Strategic Analysis Inc. (SA) and aided by Rajesh Ahluwalia and Thanh Hua from Argonne National Laboratory (ANL) and Lin Simpson at the National Renewable Energy Laboratory (NREL). Since SA coordinated the project activities of all three organizations, this report includes a technical description of all project activity. This report represents a summary of contract activities and findings under SA’s five year contract to the US Department of Energy (Award No. DE-EE0005253) and constitutes the “Final Scientific Report” deliverable. Project publications and presentations are listed in the Appendix.

  13. Limits for hydrogen production of a solar - hydrogen system in Cuernavaca, Mexico

    International Nuclear Information System (INIS)

    Arriaga, H.L.G.; Gutierrez, S.L.; Cano, U.

    2006-01-01

    In this work experimental data are used in order to estimate the production of hydrogen as a function of irradiance of a direct-interconnection of solar panel system with a SPE (Solid Polymer Electrolyte) electrolyzer (also Solar-Hydrogen system). The solar - hydrogen system, consists of a photovoltaic solar array of 36 panels (75 Watts each) of monocrystalline silicon interconnected with an electrolyzer stack of 25 cells (around 100 cm 2 of geometrical area) with a maximum hydrogen production of 1 Nm 3 /h. By the use of voltage, current density, energy consumption values of the whole solar-hydrogen system, an average efficiency up to 5% was estimated and an average of 3,800 NL of hydrogen per day can be expected. Also the maximum hydrogen production for the months of July and December (sunniest and least sunny months in the location) is predicted. (authors)

  14. Limits for hydrogen production of a solar - hydrogen system in Cuernavaca, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Arriaga, H.L.G.; Gutierrez, S.L.; Cano, U. [Instituto de Investigaciones Electricas Av. Reforma 113, col. Palmira c.p.62490 Cuernavaca Morelos (Mexico)

    2006-07-01

    In this work experimental data are used in order to estimate the production of hydrogen as a function of irradiance of a direct-interconnection of solar panel system with a SPE (Solid Polymer Electrolyte) electrolyzer (also Solar-Hydrogen system). The solar - hydrogen system, consists of a photovoltaic solar array of 36 panels (75 Watts each) of monocrystalline silicon interconnected with an electrolyzer stack of 25 cells (around 100 cm{sup 2} of geometrical area) with a maximum hydrogen production of 1 Nm{sup 3}/h. By the use of voltage, current density, energy consumption values of the whole solar-hydrogen system, an average efficiency up to 5% was estimated and an average of 3,800 NL of hydrogen per day can be expected. Also the maximum hydrogen production for the months of July and December (sunniest and least sunny months in the location) is predicted. (authors)

  15. An examination of the criteria necessary for successful worldwide deployment of isolated, renewable hydrogen stationary power systems

    International Nuclear Information System (INIS)

    Rambach, G. D.; Snyder, J. D.

    1998-01-01

    This paper examines the top-down rationale and methods for using hydrogen as an energy carrier in isolated, stationary power systems. Such an examination can be useful because it provides a framework for detailed research on subsystems and helps clarify why, when and where large-scale hydrogen use would be beneficial. It also helps define the pathway for an evolving hydrogen stationary power market worldwide. Remote, stationary power systems are an ideal market entry opportunity for hydrogen. For example, if it is sufficiently difficult for conventional fuels to reach a community, and indigenous renewable sources are present, then on-site clean energy production becomes economically competitive. Relying heavily on intermittent sources of energy requires an energy carrier system that is efficient over long periods of time. In addition, the energy carrier must not defeat the reasons for initially switching to the clean sources of energy, and must be economically feasible. Hydrogen is an elegant solution to all of these needs. Choices exist for the methods of producing hydrogen, storing and transporting it, and converting it back to useful energy. There is considerable debate about how best to increase the use of renewable hydrogen because it is not yet economically competitive with conventional energy carriers in most applications. The deployment of isolated power systems relying on hydrogen as the energy storage medium requires complex and comprehensive planning and design considerations to provide successful market entry strategies as well as appropriate system engineering. This paper will discuss the criteria and framework necessary to determine how to successfully deploy any specific system or to plan a global marketing strategy. (author)

  16. Solute carrier transporters: potential targets for digestive system neoplasms.

    Science.gov (United States)

    Xie, Jing; Zhu, Xiao Yan; Liu, Lu Ming; Meng, Zhi Qiang

    2018-01-01

    Digestive system neoplasms are the leading causes of cancer-related death all over the world. Solute carrier (SLC) superfamily is composed of a series of transporters that are ubiquitously expressed in organs and tissues of digestive systems and mediate specific uptake of small molecule substrates in facilitative manner. Given the important role of SLC proteins in maintaining normal functions of digestive system, dysregulation of these protein in digestive system neoplasms may deliver biological and clinical significance that deserves systemic studies. In this review, we critically summarized the recent advances in understanding the role of SLC proteins in digestive system neoplasms. We highlighted that several SLC subfamilies, including metal ion transporters, transporters of glucose and other sugars, transporters of urea, neurotransmitters and biogenic amines, ammonium and choline, inorganic cation/anion transporters, transporters of nucleotide, amino acid and oligopeptide organic anion transporters, transporters of vitamins and cofactors and mitochondrial carrier, may play important roles in mediating the initiation, progression, metastasis, and chemoresistance of digestive system neoplasms. Proteins in these SLC subfamilies may also have diagnostic and prognostic values to particular cancer types. Differential expression of SLC proteins in tumors of digestive system was analyzed by extracting data from human cancer database, which revealed that the roles of SLC proteins may either be dependent on the substrates they transport or be tissue specific. In addition, small molecule modulators that pharmacologically regulate the functions of SLC proteins were discussed for their possible application in the treatment of digestive system neoplasms. This review highlighted the potential of SLC family proteins as drug target for the treatment of digestive system neoplasms.

  17. Hydrogen detection systems leak response codes

    International Nuclear Information System (INIS)

    Desmas, T.; Kong, N.; Maupre, J.P.; Schindler, P.; Blanc, D.

    1990-01-01

    A loss in tightness of a water tube inside a Steam Generator Unit of a Fast Reactor is usually monitored by hydrogen detection systems. Such systems have demonstrated in the past their ability to detect a leak in a SGU. However, the increase in size of the SGU or the choice of ferritic material entails improvement of these systems in order to avoid secondary leak or to limit damages to the tube bundle. The R and D undertaken in France on this subject is presented. (author). 11 refs, 10 figs

  18. Solute carrier transporters: potential targets for digestive system neoplasms

    OpenAIRE

    Xie, Jing; Zhu, Xiao Yan; Liu, Lu Ming; Meng, Zhi Qiang

    2018-01-01

    Jing Xie,1,2 Xiao Yan Zhu,1,2 Lu Ming Liu,1,2 Zhi Qiang Meng1,2 1Department of Integrative Oncology, Fudan University Shanghai Cancer Center, 2Department of Oncology, Shanghai Medical College, Fudan University, Shanghai 200032, People’s Republic of China Abstract: Digestive system neoplasms are the leading causes of cancer-related death all over the world. Solute carrier (SLC) superfamily is composed of a series of transporters that are ubiquitously expressed in organs and tissues o...

  19. Tachyonic ionization cross sections of hydrogenic systems

    Energy Technology Data Exchange (ETDEWEB)

    Tomaschitz, Roman [Department of Physics, Hiroshima University, 1-3-1 Kagami-yama, Higashi-Hiroshima 739-8526 (Japan)

    2005-03-11

    Transition rates for induced and spontaneous tachyon radiation in hydrogenic systems as well as the transversal and longitudinal ionization cross sections are derived. We investigate the interaction of the superluminal radiation field with matter in atomic bound-bound and bound-free transitions. Estimates are given for Ly-{alpha} transitions effected by superluminal quanta in hydrogen-like ions. The tachyonic photoelectric effect is scrutinized, in the Born approximation and at the ionization threshold. The angular maxima occur at different scattering angles in the transversal and longitudinal cross sections, which can be used to sift out longitudinal tachyonic quanta in a photon flux. We calculate the tachyonic ionization and recombination cross sections for Rydberg states and study their asymptotic scaling with respect to the principal quantum number. At the ionization threshold of highly excited states of order n {approx} 10{sup 4}, the longitudinal cross section starts to compete with photoionization, in recombination even at lower levels.

  20. System-level energy efficiency is the greatest barrier to development of the hydrogen economy

    International Nuclear Information System (INIS)

    Page, Shannon; Krumdieck, Susan

    2009-01-01

    Current energy research investment policy in New Zealand is based on assumed benefits of transitioning to hydrogen as a transport fuel and as storage for electricity from renewable resources. The hydrogen economy concept, as set out in recent commissioned research investment policy advice documents, includes a range of hydrogen energy supply and consumption chains for transport and residential energy services. The benefits of research and development investments in these advice documents were not fully analyzed by cost or improvements in energy efficiency or green house gas emissions reduction. This paper sets out a straightforward method to quantify the system-level efficiency of these energy chains. The method was applied to transportation and stationary heat and power, with hydrogen generated from wind energy, natural gas and coal. The system-level efficiencies for the hydrogen chains were compared to direct use of conventionally generated electricity, and with internal combustion engines operating on gas- or coal-derived fuel. The hydrogen energy chains were shown to provide little or no system-level efficiency improvement over conventional technology. The current research investment policy is aimed at enabling a hydrogen economy without considering the dramatic loss of efficiency that would result from using this energy carrier.

  1. Influence of the formation- and passivation rate of boron-oxygen defects for mitigating carrier-induced degradation in silicon within a hydrogen-based model

    International Nuclear Information System (INIS)

    Hallam, Brett; Abbott, Malcolm; Nampalli, Nitin; Hamer, Phill; Wenham, Stuart

    2016-01-01

    A three-state model is used to explore the influence of defect formation- and passivation rates of carrier-induced degradation related to boron-oxygen complexes in boron-doped p-type silicon solar cells within a hydrogen-based model. The model highlights that the inability to effectively mitigate carrier-induced degradation at elevated temperatures in previous studies is due to the limited availability of defects for hydrogen passivation, rather than being limited by the defect passivation rate. An acceleration of the defect formation rate is also observed to increase both the effectiveness and speed of carrier-induced degradation mitigation, whereas increases in the passivation rate do not lead to a substantial acceleration of the hydrogen passivation process. For high-throughput mitigation of such carrier-induced degradation on finished solar cell devices, two key factors were found to be required, high-injection conditions (such as by using high intensity illumination) to enable an acceleration of defect formation whilst simultaneously enabling a rapid passivation of the formed defects, and a high temperature to accelerate both defect formation and defect passivation whilst still ensuring an effective mitigation of carrier-induced degradation

  2. Hydrogen production methods efficiency coupled to an advanced high temperature accelerator driven system

    International Nuclear Information System (INIS)

    Rodríguez, Daniel González; Lira, Carlos Alberto Brayner de Oliveira

    2017-01-01

    The hydrogen economy is one of the most promising concepts for the energy future. In this scenario, oil is replaced by hydrogen as an energy carrier. This hydrogen, rather than oil, must be produced in volumes not provided by the currently employed methods. In this work two high temperature hydrogen production methods coupled to an advanced nuclear system are presented. A new design of a pebbled-bed accelerator nuclear driven system called TADSEA is chosen because of the advantages it has in matters of transmutation and safety. For the conceptual design of the high temperature electrolysis process a detailed computational fluid dynamics model was developed to analyze the solid oxide electrolytic cell that has a huge influence on the process efficiency. A detailed flowsheet of the high temperature electrolysis process coupled to TADSEA through a Brayton gas cycle was developed using chemical process simulation software: Aspen HYSYS®. The model with optimized operating conditions produces 0.1627 kg/s of hydrogen, resulting in an overall process efficiency of 34.51%, a value in the range of results reported by other authors. A conceptual design of the iodine-sulfur thermochemical water splitting cycle was also developed. The overall efficiency of the process was calculated performing an energy balance resulting in 22.56%. The values of efficiency, hydrogen production rate and energy consumption of the proposed models are in the values considered acceptable in the hydrogen economy concept, being also compatible with the TADSEA design parameters. (author)

  3. Hydrogen production methods efficiency coupled to an advanced high temperature accelerator driven system

    Energy Technology Data Exchange (ETDEWEB)

    Rodríguez, Daniel González; Lira, Carlos Alberto Brayner de Oliveira [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Departamento de Energia Nuclear; Fernández, Carlos García, E-mail: danielgonro@gmail.com, E-mail: mmhamada@ipen.br [Instituto Superior de Tecnologías y Ciencias aplicadas (InSTEC), La Habana (Cuba)

    2017-07-01

    The hydrogen economy is one of the most promising concepts for the energy future. In this scenario, oil is replaced by hydrogen as an energy carrier. This hydrogen, rather than oil, must be produced in volumes not provided by the currently employed methods. In this work two high temperature hydrogen production methods coupled to an advanced nuclear system are presented. A new design of a pebbled-bed accelerator nuclear driven system called TADSEA is chosen because of the advantages it has in matters of transmutation and safety. For the conceptual design of the high temperature electrolysis process a detailed computational fluid dynamics model was developed to analyze the solid oxide electrolytic cell that has a huge influence on the process efficiency. A detailed flowsheet of the high temperature electrolysis process coupled to TADSEA through a Brayton gas cycle was developed using chemical process simulation software: Aspen HYSYS®. The model with optimized operating conditions produces 0.1627 kg/s of hydrogen, resulting in an overall process efficiency of 34.51%, a value in the range of results reported by other authors. A conceptual design of the iodine-sulfur thermochemical water splitting cycle was also developed. The overall efficiency of the process was calculated performing an energy balance resulting in 22.56%. The values of efficiency, hydrogen production rate and energy consumption of the proposed models are in the values considered acceptable in the hydrogen economy concept, being also compatible with the TADSEA design parameters. (author)

  4. Present status of research on hydrogen energy and perspective of HTGR hydrogen production system

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Yoshiaki; Ogawa, Masuro; Akino, Norio [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment] [and others

    2001-03-01

    A study was performed to make a clear positioning of research and development on hydrogen production systems with a High Temperature Gas-cooled Reactor (HTGR) under currently promoting at the Japan Atomic Energy Research Institute through a grasp of the present status of hydrogen energy, focussing on its production and utilization as an energy in future. The study made clear that introduction of safe distance concept for hydrogen fire and explosion was practicable for a HTGR hydrogen production system, including hydrogen properties and need to provide regulations applying to handle hydrogen. And also generalization of hydrogen production processes showed technical issues of the HTGR system. Hydrogen with HTGR was competitive to one with fossil fired system due to evaluation of production cost. Hydrogen is expected to be used as promising fuel of fuel cell cars in future. In addition, the study indicated that there were a large amount of energy demand alternative to high efficiency power generation and fossil fuel with nuclear energy through the structure of energy demand and supply in Japan. Assuming that hydrogen with HTGR meets all demand of fuel cell cars, an estimation would show introduction of the maximum number of about 30 HTGRs with capacity of 100 MWt from 2020 to 2030. (author)

  5. 75 FR 57191 - Compliance With Interstate Motor Carrier Noise Emission Standards: Exhaust Systems

    Science.gov (United States)

    2010-09-20

    ... 28, 1975, the Federal Highway Administration (FHWA)'s Bureau of Motor Carrier Safety published in the... DEPARTMENT OF TRANSPORTATION Federal Motor Carrier Safety Administration 49 CFR Part 325 [Docket...: Exhaust Systems AGENCY: Federal Motor Carrier Safety Administration, DOT. ACTION: Direct final rule...

  6. 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...

  7. Gelatin as a carrier system for delivery of polyphenols compounds

    Directory of Open Access Journals (Sweden)

    Jovanović Aleksandra

    2017-01-01

    Full Text Available In the present study, the influence of different encapsulation techniques (lyophilization and spray drying on gelatin, as a carrier system for delivery of polyphenols compounds, on wild thyme extracts and on encapsulated extracts was investigated. FTIR analyses has shown the presence of carbohydrates, polysaccharides, polyphenols, flavonoids, monoterpenes and carboxylates in the dried extracts, while FTIR spectrum of the encapsulated extracts has shown almost exclusively gelatin-based stripes, indicating the efficient encapsulation of the active ingredients of the extracts and therefore their protection. Scanning electron microscopy has shown that the lyophilization process produced irregularly shaped particles, while spray drying formed spherical and pseudo-spherical particles with rough surface. Using the method of diffraction of laser light, it has been found that spray dried encapsulate possessed significantly lower particle size and significantly better uniformity in comparison to the lyophilized sample. According to the results obtained in differential scanning calorimetry, endothermic peak of lyophilized gelatin encapsulate appeared at higher temperature, thus it can be concluded that lyophilized sample was more thermostable than spray dried parallel. Additionally, the values of enthalpy of gelatin encapsulates were significantly higher compared to pure extracts, which confirmed the presence of stabilizing interactions between the encapsulated components and a carrier.

  8. Microchannel Reactor System for Catalytic Hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Adeniyi Lawal; Woo Lee; Ron Besser; Donald Kientzler; Luke Achenie

    2010-12-22

    We successfully demonstrated a novel process intensification concept enabled by the development of microchannel reactors, for energy efficient catalytic hydrogenation reactions at moderate temperature, and pressure, and low solvent levels. We designed, fabricated, evaluated, and optimized a laboratory-scale microchannel reactor system for hydrogenation of onitroanisole and a proprietary BMS molecule. In the second phase of the program, as a prelude to full-scale commercialization, we designed and developed a fully-automated skid-mounted multichannel microreactor pilot plant system for multiphase reactions. The system is capable of processing 1 – 10 kg/h of liquid substrate, and an industrially relevant immiscible liquid-liquid was successfully demonstrated on the system. Our microreactor-based pilot plant is one-of-akind. We anticipate that this process intensification concept, if successfully demonstrated, will provide a paradigm-changing basis for replacing existing energy inefficient, cost ineffective, environmentally detrimental slurry semi-batch reactor-based manufacturing practiced in the pharmaceutical and fine chemicals industries.

  9. Carrier-Based Drug Delivery System for Treatment of Acne

    Science.gov (United States)

    Vyas, Amber; Kumar Sonker, Avinesh

    2014-01-01

    Approximately 95% of the population suffers at some point in their lifetime from acne vulgaris. Acne is a multifactorial disease of the pilosebaceous unit. This inflammatory skin disorder is most common in adolescents but also affects neonates, prepubescent children, and adults. Topical conventional systems are associated with various side effects. Novel drug delivery systems have been used to reduce the side effect of drugs commonly used in the topical treatment of acne. Topical treatment of acne with active pharmaceutical ingredients (API) makes direct contact with the target site before entering the systemic circulation which reduces the systemic side effect of the parenteral or oral administration of drug. The objective of the present review is to discuss the conventional delivery systems available for acne, their drawbacks, and limitations. The advantages, disadvantages, and outcome of using various carrier-based delivery systems like liposomes, niosomes, solid lipid nanoparticles, and so forth, are explained. This paper emphasizes approaches to overcome the drawbacks and limitations associated with the conventional system and the advances and application that are poised to further enhance the efficacy of topical acne formulations, offering the possibility of simplified dosing regimen that may improve treatment outcomes using novel delivery system. PMID:24688376

  10. Ultrafast carrier dynamics unravel role of surface ligands and metal domain size on the photocatalytic hydrogen evolution efficiency of Au-tipped CdS nanorods: an ultrafast transient absorption spectroscopy study

    Science.gov (United States)

    Ben-Shahar, Yuval; Kriegel, Ilka; Scotognella, Francesco; Waiskopf, Nir; Dal Conte, Stefano; Moretti, Luca; Cerullo, Giulio; Rabani, Eran; Banin, Uri

    2017-02-01

    Semiconductor-metal hybrid nanostructures are interesting materials for photocatalysis. Their tunable properties offer a highly controllable platform to design light-induced charge separation, a key to their function in photocatalytic water splitting. Hydrogen evolution quantum yields are influenced by factors as size, shape, material and morphology of the system, additionally the surface coating or the metal domain size play a dominant role. In this paper we present a study on a well-defined model system of Au-tipped CdS nanorods. We use transient absorption spectroscopy to get insights into the charge carrier dynamics after photoexcitation of the bandgap of CdS nanorods. The study of charge transfer processes combined with the hydrogen evolution efficiency unravels the effects of surface coating and the gold tip size on the photocatalytic efficiency. Differences in efficiency with various surface ligands are primarily ascribed to the effects of surface passivation. Surface trapping of charge carriers is competing with effective charge separation, a prerequisite for photocatalysis, leading to the observed lower hydrogen production quantum yields. Interestingly, non-monotonic hydrogen evolution efficiency with size of the gold tip is observed, resulting in an optimal metal domain size for the most efficient photocatalysis. These results are explained by the sizedependent interplay of the metal domain charging and the relative band-alignments. Taken together our findings are of major importance for the potential application of hybrid nanoparticles as photocatalysts.

  11. Potential of the HTGR hydrogen cogeneration system in Japan

    International Nuclear Information System (INIS)

    Nishihara, Tetsuo; Mouri, Tomoaki; Kunitomi, Kazuhiko

    2007-01-01

    A high temperature gas cooled reactor (HTGR) is one of the next generation nuclear systems. The HTGR hydrogen cogeneration system can produce not only electricity but also hydrogen. Then it has a potential to supply massive low-cost hydrogen without greenhouse gas emission for the future hydrogen society. Japan Atomic Energy Agency (JAEA) has been carried out the design study of the HTGR hydrogen cogeneration system (GTHTR300C). The thermal power of the reactor is 600 MW. The hydrogen production plant utilizes 370 MW and can supply 52,000 m 3 /h (0.4 Bm 3 /y) of hydrogen. Present industrial hydrogen production capacity in Japan is about 18 Bm 3 /y and it will decrease by 15 Bm 3 /y in 2030 due to the aging facilities. On the other hand, the hydrogen demand for fuel cell vehicle (FCV) in 2030 is estimated at 15 Bm 3 /y at a maximum. Since the hydrogen supply may be short after 2030, the additional hydrogen should be produced by clean hydrogen process to reduce greenhouse gas emission. This hydrogen shortage is a potential market for the GTHTR300C. The hydrogen production cost of GTHTR300C is estimated at 20.5 JPY/Nm 3 which has an economic competitiveness against other industrial hydrogen production processes. 38 units of the GTHTR300C can supply a half of this shortage which accounts for the 33% of hydrogen demand for FCV in 2100. According to the increase of hydrogen demand, the GTHTR300C should be constructed after 2030. (author)

  12. Helium refrigeration system for hydrogen liquefaction applications

    Science.gov (United States)

    Nair, J. Kumar, Sr.; Menon, RS; Goyal, M.; Ansari, NA; Chakravarty, A.; Joemon, V.

    2017-02-01

    Liquid hydrogen around 20 K is used as cold moderator for generating “cold neutron beam” in nuclear research reactors. A cryogenic helium refrigeration system is the core upon which such hydrogen liquefaction applications are built. A thermodynamic process based on reversed Brayton cycle with two stage expansion using high speed cryogenic turboexpanders (TEX) along with a pair of compact high effectiveness process heat exchangers (HX), is well suited for such applications. An existing helium refrigeration system, which had earlier demonstrated a refrigeration capacity of 470 W at around 20 K, is modified based on past operational experiences and newer application requirements. Modifications include addition of a new heat exchanger to simulate cryogenic process load and two other heat exchangers for controlling the temperatures of helium streams leading out to the application system. To incorporate these changes, cryogenic piping inside the cold box is suitably modified. This paper presents process simulation, sizing of new heat exchangers as well as fabrication aspects of the modified cryogenic process piping.

  13. Borazine-boron nitride hybrid hydrogen storage system

    Science.gov (United States)

    Narula, Chaitanya K [Knoxville, TN; Simonson, J Michael [Knoxville, TN; Maya, Leon [Knoxville, TN; Paine, Robert T [Albuquerque, NM

    2008-04-22

    A hybrid hydrogen storage composition includes a first phase and a second phase adsorbed on the first phase, the first phase including BN for storing hydrogen by physisorption and the second phase including a borazane-borazine system for storing hydrogen in combined form as a hydride.

  14. Energy Systems With Renewable Hydrogen Compared to Direct Use of Renewable Energy in Austria

    International Nuclear Information System (INIS)

    Gerfried Jungmeier; Kurt Konighofer; Josef Spitzer; R Haas; A Ajanovic

    2006-01-01

    The current Austrian energy system has a renewable energy share of 20% - 11% hydropower and 9 % biomass - of total primary energy consumption. Whereas a possible future introduction of renewable hydrogen must be seen in the context of current energy policies in Austria e.g. increase of energy efficiency and use of renewable energy, reduction of greenhouse gas emissions. The aim of the research project is a life cycle based comparison of energy systems with renewable hydrogen from hydropower, wind, photovoltaic and biomass compared to the direct use of renewable energy for combined heat and power applications and transportation services. In particular this paper focuses on the main question, if renewable energy should be used directly or indirectly via renewable hydrogen. The assessment is based on a life cycle approach to analyse the energy efficiency, the material demand, the greenhouse gas emissions and economic aspects e.g. energy costs and some qualitative aspects e.g. energy service. The overall comparison of the considered energy systems for transportation service and combined heat and electricity application shows, that renewable hydrogen might be beneficial mainly for transportation services, if the electric vehicle will not be further developed to a feasibly wide-spread application for transportation service in future. For combined heat and electricity production there is no advantage of renewable hydrogen versus the direct use of renewable energy. Conclusions for Austria are therefore: 1) renewable hydrogen is an interesting energy carrier and might play an important role in a future sustainable Austrian energy system; 2) renewable hydrogen applications look most promising in the transportation sector; 3) renewable hydrogen applications will be of low importance for combined heat and electricity applications, as existing technologies for direct use of renewable energy for heat and electricity are well developed and very efficient; 4) In a future '100

  15. Hydrogen.

    Science.gov (United States)

    Bockris, John O'M

    2011-11-30

    The idea of a "Hydrogen Economy" is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO₂ in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H₂ from the electrolyzer. Methanol made with CO₂ from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan). Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs) by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  16. Life cycle assessment of hydrogen production and fuel cell systems

    International Nuclear Information System (INIS)

    Dincer, I.

    2007-01-01

    This paper details life cycle assessment (LCA) of hydrogen production and fuel cell system. LCA is a key tool in hydrogen and fuel cell technologies for design, analysis, development; manufacture, applications etc. Energy efficiencies and greenhouse gases and air pollution emissions have been evaluated in all process steps including crude oil and natural gas pipeline transportation, crude oil distillation, natural gas reprocessing, wind and solar electricity generation , hydrogen production through water electrolysis and gasoline and hydrogen distribution and utilization

  17. Configuration and technology implications of potential nuclear hydrogen system applications.

    Energy Technology Data Exchange (ETDEWEB)

    Conzelmann, G.; Petri, M.; Forsberg, C.; Yildiz, B.; ORNL

    2005-11-05

    Nuclear technologies have important distinctions and potential advantages for large-scale generation of hydrogen for U.S. energy services. Nuclear hydrogen requires no imported fossil fuels, results in lower greenhouse-gas emissions and other pollutants, lends itself to large-scale production, and is sustainable. The technical uncertainties in nuclear hydrogen processes and the reactor technologies needed to enable these processes, as well waste, proliferation, and economic issues must be successfully addressed before nuclear energy can be a major contributor to the nation's energy future. In order to address technical issues in the time frame needed to provide optimized hydrogen production choices, the Nuclear Hydrogen Initiative (NHI) must examine a wide range of new technologies, make the best use of research funding, and make early decisions on which technology options to pursue. For these reasons, it is important that system integration studies be performed to help guide the decisions made in the NHI. In framing the scope of system integration analyses, there is a hierarchy of questions that should be addressed: What hydrogen markets will exist and what are their characteristics? Which markets are most consistent with nuclear hydrogen? What nuclear power and production process configurations are optimal? What requirements are placed on the nuclear hydrogen system? The intent of the NHI system studies is to gain a better understanding of nuclear power's potential role in a hydrogen economy and what hydrogen production technologies show the most promise. This work couples with system studies sponsored by DOE-EE and other agencies that provide a basis for evaluating and selecting future hydrogen production technologies. This assessment includes identifying commercial hydrogen applications and their requirements, comparing the characteristics of nuclear hydrogen systems to those market requirements, evaluating nuclear hydrogen configuration options

  18. Design of the electrolyzer for the solar hydrogen production system

    International Nuclear Information System (INIS)

    Ibrahim, M.; Kamaruzzaman Sopian; Wan Ramli Wan Daud

    2006-01-01

    This paper presents the theoretical design of hydrogen system. Also, it shown the details steps of theoretical calculation to produce the required amount of hydrogen. Hydrogen is considered the fuel of the future. It is promising alternative for fossil fuel. Since, it is non-pollutant and renewable. The system contains and required equipment are photovoltaic panel, energy storage battery, converter, electrolyzer and hydrogen storage. By using 1.7 V supplied by PV, the simulation results gives 89 1/day of hydrogen. Since, the electrolyzer efficiency assumed to be 50%

  19. [Hydrogen systems analysis, education, and outreach

    Energy Technology Data Exchange (ETDEWEB)

    None

    1998-01-01

    This paper illustrates a search of web sites on the keyword, Hydrogen, and a second search combining keywords, Hydrogen and Renewable Energy. Names, addresses, and E-mail addresses or web site URLs are given for a number of companies and government or commercial organizations dealing with hydrogen fuel cells. Finally, brief summaries are given on hydrogen research projects at the National Renewable Energy Laboratory.

  20. Genesis and mobility of natural hydrogen: energy source or storable energy carrier?

    International Nuclear Information System (INIS)

    Vacquand, Ch.

    2011-01-01

    This PhD thesis is a study of the production of hydrogen (H 2 ) in several types of continental contexts and an experimental approach of its migration in geological media. In a first part, H 2 -rich gases that were associated with methane CH 4 and nitrogen N 2 from Oman, the Philippines, Turkey and Kansas (USA) were analyzed. Systematic analyses of stable isotopes of carbon, hydrogen and noble gases indicate a relatively low-temperature and shallow aquifer origin for this H 2 . At the surface, we made clear that the H 2 seepage was associated with high-pH sources that capture the atmospheric CO 2 , forming calcite and aragonite. The very heavy carbon isotopic signatures for most of the measured methane suggest a reduction of the inorganic dissolved carbon by this H 2 . We propose that, as in the case of hydrothermal oceanic serpentinization, but at much lower temperatures, the connection between H 2 production and the ultra basic rocks is due to the presence of abundant iron (II) and to adequate redox conditions that allow the reduction of water to H 2 and a good conservation of this H 2 , a variable part of which is converted to methane, depending on the CO 2 activity. The combination of this H 2 generation model with noble gases migration, hydrogeological and geological data allowed us to estimate a global flux of H 2 production from the large ophiolitic belts in the world of 10 13 to 10 18 m 3 /yr. In a second part, we realized migration experiments of H 2 in natural or reconstituted geological media in a laboratory. We showed that this migration is not particularly important compared to that of other gases and quite close to that of argon. This moderate migration, lower than that of CO 2 in porous saturated media is due to a relatively low solubility of H 2 in water and to an effective diffusion coefficient in porous media lower than for helium and close to that of argon. Since H 2 does neither migrate faster nor more efficiently than CH 4 for example, these

  1. System Frequency as Information Carrier in AC Power Systems

    DEFF Research Database (Denmark)

    Douglass, Philip James; Heussen, Kai; You, Shi

    2015-01-01

    Power generators contain control systems able to regulate system frequency, but the frequency setpoint values are only rarely modified from nominal values. This paper describes design considerations for a communication system from generators to frequency sensitive distributed energy resourc es (FS......-DER) using changes to frequency setpoint values of genera- tors. Signaling discrete system states by generating off-nominal system frequency values can be used as a novel narrowband unidirectional broadcast communications channel. This paper describes two protocols for utilizing off-nominal frequencies...... to carry information: First, a protocol for dispatching blocks of FS- DER that is suitable for systems restricted to relatively slow rates of change of frequency (ROCOF). Second, for systems that allow higher ROCOF values, the feasibility of using power generation resources as a power line communication...

  2. Biogas and Hydrogen Systems Market Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Milbrandt, Anelia [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bush, Brian [National Renewable Energy Lab. (NREL), Golden, CO (United States); Melaina, Marc [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-31

    This analysis provides an overview of the market for biogas-derived hydrogen and its use in transportation applications. It examines the current hydrogen production technologies from biogas, capacity and production, infrastructure, potential and demand, as well as key market areas. It also estimates the production cost of hydrogen from biogas and provides supply curves at a national level and at point source.

  3. Hydrogen control in the System 80+TM ALWR design

    International Nuclear Information System (INIS)

    Schneider, R.E.; Jacob, M.C.; Carpentino, F.L.; Wachowiak, R.M.

    2004-01-01

    This paper provides an assessment of the features built into the System 80 +TM Advanced Light Water Reactor (ALWR) design for controlling hydrogen concentration during a hypothetical severe accident. Although the significantly larger System 80 + containment volume serves to passively maintain the global average below detonable limits, the design incorporates a Hydrogen Mitigation System (HMS) to further reduce the local hydrogen concentration. The HMS consists of a large number of hydrogen ignitors distributed within the containment to selectively burn-off hydrogen at low concentrations. The criteria for the placement of these igniters are discussed along with an assessment of the effectiveness of the igniters to control the hydrogen concentrations. This assessment, which was performed using the generalized containment model of the MAAP 4 code, evaluated the potential for hydrogen build-up in the containment and calculated the best-estimate response of the igniters. (author)

  4. Standard-D hydrogen monitoring system, system design description

    International Nuclear Information System (INIS)

    Schneider, T.C.

    1996-01-01

    During most of the year, it is assumed that the vapor space in the 177 radioactive waste tanks on the Hanford Project site contain a uniform mixture of gases. Several of these waste tanks (currently twenty-five, 6 Double Shell Tanks and 19 Single Shell Tanks) were identified as having the potential for the buildup of gasses to a flammable level. An active ventilation system in the Double Shell Tanks and a passive ventilation system in the Single Shell Tanks provides a method of expelling gasses from the tanks. A gas release from a tank causes a temporary rise in the tank pressure, and a potential for increased concentration of hydrogen gas in the vapor space. The gas is released via the ventilation systems until a uniform gas mixture in the vapor space is once again achieved. The Standard Hydrogen Monitoring System (SHMS) is designed to monitor and quantify the percent hydrogen concentration during these potential gas releases. This document describes the design of the Standard-D Hydrogen Monitoring System, (SHMS-D) and its components as it differs from the original SHMS

  5. Nanostructured, complex hydride systems for hydrogen generation

    Directory of Open Access Journals (Sweden)

    Robert A. Varin

    2015-02-01

    Full Text Available Complex hydride systems for hydrogen (H2 generation for supplying fuel cells are being reviewed. In the first group, the hydride systems that are capable of generating H2 through a mechanical dehydrogenation phenomenon at the ambient temperature are discussed. There are few quite diverse systems in this group such as lithium alanate (LiAlH4 with the following additives: nanoiron (n-Fe, lithium amide (LiNH2 (a hydride/hydride system and manganese chloride MnCl2 (a hydride/halide system. Another hydride/hydride system consists of lithium amide (LiNH2 and magnesium hydride (MgH2, and finally, there is a LiBH4-FeCl2 (hydride/halide system. These hydride systems are capable of releasing from ~4 to 7 wt.% H2 at the ambient temperature during a reasonably short duration of ball milling. The second group encompasses systems that generate H2 at slightly elevated temperature (up to 100 °C. In this group lithium alanate (LiAlH4 ball milled with the nano-Fe and nano-TiN/TiC/ZrC additives is a prominent system that can relatively quickly generate up to 7 wt.% H2 at 100 °C. The other hydride is manganese borohydride (Mn(BH42 obtained by mechano-chemical activation synthesis (MCAS. In a ball milled (2LiBH4 + MnCl2 nanocomposite, Mn(BH42 co-existing with LiCl can desorb ~4.5 wt.% H2 at 100 °C within a reasonable duration of dehydrogenation. Practical application aspects of hydride systems for H2 generation/storage are also briefly discussed.

  6. Polymers for hydrogen infrastructure and vehicle fuel systems :

    Energy Technology Data Exchange (ETDEWEB)

    Barth, Rachel Reina; Simmons, Kevin L.; San Marchi, Christopher W.

    2013-10-01

    This document addresses polymer materials for use in hydrogen service. Section 1 summarizes the applications of polymers in hydrogen infrastructure and vehicle fuel systems and identifies polymers used in these applications. Section 2 reviews the properties of polymer materials exposed to hydrogen and/or high-pressure environments, using information obtained from published, peer-reviewed literature. The effect of high pressure on physical and mechanical properties of polymers is emphasized in this section along with a summary of hydrogen transport through polymers. Section 3 identifies areas in which fuller characterization is needed in order to assess material suitability for hydrogen service.

  7. 42 CFR 405.512 - Carriers' procedural terminology and coding systems.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 2 2010-10-01 2010-10-01 false Carriers' procedural terminology and coding systems... Determining Reasonable Charges § 405.512 Carriers' procedural terminology and coding systems. (a) General. Procedural terminology and coding systems are designed to provide physicians and third party payers with a...

  8. High and rapid hydrogen release from thermolysis of ammonia borane near PEM fuel cell operating temperature

    Science.gov (United States)

    Varma, Arvind; Hwang, Hyun Tae; Al-Kukhun, Ahmad

    2016-11-15

    A system for generating and purifying hydrogen. To generate hydrogen, the system includes inlets configured to receive a hydrogen carrier and an inert insulator, a mixing chamber configured to combine the hydrogen carrier and the inert insulator, a heat exchanger configured to apply heat to the mixture of hydrogen carrier and the inert insulator, wherein the applied heat results in the generation of hydrogen from the hydrogen carrier, and an outlet configured to release the generated hydrogen. To purify hydrogen, the system includes a primary inlet to receive a starting material and an ammonia filtration subassembly, which may include an absorption column configured to absorb the ammonia into water for providing purified hydrogen at a first purity level. The ammonia filtration subassembly may also include an adsorbent member configured to adsorb ammonia from the starting material into an adsorbent for providing purified hydrogen at a second purity level.

  9. Safety Standard for Hydrogen and Hydrogen Systems: Guidelines for Hydrogen System Design, Materials Selection, Operations, Storage and Transportation. Revision

    Science.gov (United States)

    1997-01-01

    The NASA Safety Standard, which establishes a uniform process for hydrogen system design, materials selection, operation, storage, and transportation, is presented. The guidelines include suggestions for safely storing, handling, and using hydrogen in gaseous (GH2), liquid (LH2), or slush (SLH2) form whether used as a propellant or non-propellant. The handbook contains 9 chapters detailing properties and hazards, facility design, design of components, materials compatibility, detection, and transportation. Chapter 10 serves as a reference and the appendices contained therein include: assessment examples; scaling laws, explosions, blast effects, and fragmentation; codes, standards, and NASA directives; and relief devices along with a list of tables and figures, abbreviations, a glossary and an index for ease of use. The intent of the handbook is to provide enough information that it can be used alone, but at the same time, reference data sources that can provide much more detail if required.

  10. Containment hydrogen removal system for a nuclear power plant

    International Nuclear Information System (INIS)

    Callaghan, V.M.; Flynn, E.P.; Pokora, B.M.

    1984-01-01

    A hydrogen removal system (10) separates hydrogen from the containment atmosphere of a nuclear power plant using a hydrogen permeable membrane separator (30). Water vapor is removed by condenser (14) from a gas stream withdrawn from the containment atmosphere. The gas stream is then compressed by compressor (24) and cooled (28,34) to the operating temperature of the hydrogen permeable membrane separator (30). The separator (30) separates the gas stream into a first stream, rich in hydrogen permeate, and a second stream that is hydrogen depleted. The separated hydrogen is passed through a charcoal adsorber (48) to adsorb radioactive particles that have passed through the hydrogen permeable membrane (44). The hydrogen is then flared in gas burner (52) with atmospheric air and the combustion products vented to the plant vent. The hydrogen depleted stream is returned to containment through a regenerative heat exchanger (28) and expander (60). Energy is extracted from the expander (60) to drive the compressor (24) thereby reducing the energy input necessary to drive the compressor (24) and thus reducing the hydrogen removal system (10) power requirements

  11. Preliminary Cost Estimates for Nuclear Hydrogen Production: HTSE System

    International Nuclear Information System (INIS)

    Yang, K. J.; Lee, K. Y.; Lee, T. H.

    2008-01-01

    KAERI is now focusing on the research and development of the key technologies required for the design and realization of a nuclear hydrogen production system. As a preliminary study of cost estimates for nuclear hydrogen systems, the hydrogen production costs of the nuclear energy sources benchmarking GTMHR and PBMR are estimated in the necessary input data on a Korean specific basis. G4-ECONS was appropriately modified to calculate the cost for hydrogen production of HTSE (High Temperature Steam Electrolysis) process with VHTR (Very High Temperature nuclear Reactor) as a thermal energy source. The estimated costs presented in this paper show that hydrogen production by the VHTR could be competitive with current techniques of hydrogen production from fossil fuels if CO 2 capture and sequestration is required. Nuclear production of hydrogen would allow large-scale production of hydrogen at economic prices while avoiding the release of CO 2 . Nuclear production of hydrogen could thus become the enabling technology for the hydrogen economy. The major factors that would affect the cost of hydrogen were also discussed

  12. Magnetic suspension and pointing system. [on a carrier vehicle

    Science.gov (United States)

    Anderson, W. W.; Groom, N. J. (Inventor)

    1979-01-01

    Apparatus for providing accurate pointing of instruments on a carrier vehicle and for providing isolation of the instruments from the vehicle's motion disturbances is presented. The apparatus includes two assemblies, with connecting interfaces, each assembly having a separate function. The first assembly is attached to the carrier vehicle and consists of an azimuth gimbal and an elevation gimbal which provide coarse pointing of the instruments by allowing two rotations of the instruments relative to the carrier vehicle. The second or vernier pointing assembly is made up of magnetic suspension and fine pointing actuators, roll motor segments, and an instrument mounting plate around which a continuous annular rim is attached which provides appropriate magnetic circuits for the actuators and the roll motor segments. The vernier pointing assembly provides six degree-of-freedom isolation from carrier motion disturbances.

  13. Hydrogen as an energy carrier in substituting petroleum. Demonstration project: automobiles driven by nuclear energy

    International Nuclear Information System (INIS)

    Donne, M.D.; Dorner, S.; Kessler, G.; Schretzmann, K.

    1983-01-01

    The substitution of oil in motor vehicles by means of coal upgrading is paid by a consumption of primary energy and the persistence of a high environmental impact as noise and off-gases. Alternative systems, based on electric traction by electricity from H 2 -fuel cells have a high development potential. The Karlsruhe Nuclear Center has endeavoured to demonstrate the feasibility of this traction system. In particular an assessment of the efficiency and costs of the H 2 -fuel cell for vehicle traction is given. The paper discusses the various possibilities of on-board H 2 storage. Finally the work being presently performed in Karlsruhe is briefly described. (author)

  14. Hydrogen

    Directory of Open Access Journals (Sweden)

    John O’M. Bockris

    2011-11-01

    Full Text Available The idea of a “Hydrogen Economy” is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO2 in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H2 from the electrolyzer. Methanol made with CO2 from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan. Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  15. Rhodamine/Nanodiamond as a System Model for Drug Carrier.

    Science.gov (United States)

    Reina, G; Orlanducci, S; Cairone, C; Tamburri, E; Lenti, S; Cianchetta, I; Rossi, M; Terranova, M L

    2015-02-01

    In this paper we present some strategies that are being developed in our labs towards enabling nanodiamond-based applications for drug delivery. Rhodamine B (RhB) has been choosen as model molecule to study the loading of nanodiamonds with active moieties and the conditions for their controlled release. In order to test the chemical/physical interactions between functionalized detonation nanodiamond (DND) and complex molecules, we prepared and tested different RhB@DND systems, with RhB adsorbed or linked by ionic bonding to the DND surface. The chemical state of the DND surfaces before conjugation with the RhB molecules, and the chemical features of the DND-RhB interactions have been deeply analysed by coupling DND with Au nanoparticles and taking advantage of surface enhanced Raman spectroscopy SERS. The effects due to temperature and pH variations on the process of RhB release from the DND carrier have been also investigated. The amounts of released molecules are consistent with those required for effective drug action in conventional therapeutic applications, and this makes the DND promising nanostructured cargos for drug delivery applications.

  16. Online Systems for Oversize and Overweight Freight Permitting and Motor Carrier Credentialing : Transportation Research Synthesis.

    Science.gov (United States)

    2017-09-01

    MnDOT uses two online systems implemented in the 1990s to issue and manage permits for oversize/overweight (OS/OW) freight and motor carrier credentials: - RouteBuilder, an OS/OW permitting system with a routing component. - Motor Carrier Information...

  17. Carrier system for a plant extract or bioactive compound from a plant

    DEFF Research Database (Denmark)

    2018-01-01

    This invention relates to a carrier system for use in producing a beverage with a metered amount of plant extract or bioactive compound.......This invention relates to a carrier system for use in producing a beverage with a metered amount of plant extract or bioactive compound....

  18. High-frequency conductivity of optically excited charge carriers in hydrogenated nanocrystalline silicon investigated by spectroscopic femtosecond pump–probe reflectivity measurements

    Energy Technology Data Exchange (ETDEWEB)

    He, Wei [University of Birmingham, School of Physics and Astronomy, Birmingham B15 2TT (United Kingdom); Yurkevich, Igor V. [Aston University, Nonlinearity and Complexity Research Group, Birmingham B4 7ET (United Kingdom); Zakar, Ammar [University of Birmingham, School of Physics and Astronomy, Birmingham B15 2TT (United Kingdom); Kaplan, Andrey, E-mail: a.kaplan.1@bham.ac.uk [University of Birmingham, School of Physics and Astronomy, Birmingham B15 2TT (United Kingdom)

    2015-10-01

    We report an investigation into the high-frequency conductivity of optically excited charge carriers far from equilibrium with the lattice. The investigated samples consist of hydrogenated nanocrystalline silicon films grown on a thin film of silicon oxide on top of a silicon substrate. For the investigation, we used an optical femtosecond pump–probe setup to measure the reflectance change of a probe beam. The pump beam ranged between 580 and 820 nm, whereas the probe wavelength spanned 770 to 810 nm. The pump fluence was fixed at 0.6 mJ/cm{sup 2}. We show that at a fixed delay time of 300 fs, the conductivity of the excited electron–hole plasma is described well by a classical conductivity model of a hot charge carrier gas found at Maxwell–Boltzmann distribution, while Fermi–Dirac statics is not suitable. This is corroborated by values retrieved from pump–probe reflectance measurements of the conductivity and its dependence on the excitation wavelength and carrier temperature. The conductivity decreases monotonically as a function of the excitation wavelength, as expected for a nondegenerate charge carrier gas. - Highlights: • We study high‐frequency conductivity of excited hydrogenated nanocrystalline silicon. • Reflectance change was measured as a function of pump and probe wavelength. • Maxwell–Boltzmann transport theory was used to retrieve the conductivity. • The conductivity decreases monotonically as a function of the pump wavelength.

  19. 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)

  20. H2T liquid hydrogen delivery system

    International Nuclear Information System (INIS)

    Roy, S.

    2002-01-01

    This Power Point presentation provides a preliminary evaluation of the cost of delivering liquid hydrogen produced in Quebec to hydrogen fuelled cars in Germany. The presentation describes the chain of events regarding liquid hydrogen delivery, beginning with the production of hydrogen from an initial source of hydro power. Water passes through an electrolyzer where hydrogen is liquefied and then placed into a container which is transported to market via truck, rail or tanker. Once transported, the hydrogen fuel is made available for consumers at refueling stations. The paper lists the costs related to transportation with reference to safety rules, pure transportation costs, leasing fees for the containers, and permission of customs duties for the import of hydrogen and export of empty containers between Quebec and Germany. A graph depicting a typical refueling station in Germany and the refueling events per hour was presented. For safety reasons, refueling is performed by a refueling robot. A blueprint of safety and protection distances at a refueling station was also presented. tabs., figs

  1. Compact hydrogen production systems for solid polymer fuel cells

    Science.gov (United States)

    Ledjeff-Hey, K.; Formanski, V.; Kalk, Th.; Roes, J.

    Generally there are several ways to produce hydrogen gas from carbonaceous fuels like natural gas, oil or alcohols. Most of these processes are designed for large-scale industrial production and are not suitable for a compact hydrogen production system (CHYPS) in the power range of 1 kW. In order to supply solid polymer fuel cells (SPFC) with hydrogen, a compact fuel processor is required for mobile applications. The produced hydrogen-rich gas has to have a low level of harmful impurities; in particular the carbon monoxide content has to be lower than 20 ppmv. Integrating the reaction step, the gas purification and the heat supply leads to small-scale hydrogen production systems. The steam reforming of methanol is feasible at copper catalysts in a low temperature range of 200-350°C. The combination of a small-scale methanol reformer and a metal membrane as purification step forms a compact system producing high-purity hydrogen. The generation of a SPFC hydrogen fuel gas can also be performed by thermal or catalytic cracking of liquid hydrocarbons such as propane. At a temperature of 900°C the decomposition of propane into carbon and hydrogen takes place. A fuel processor based on this simple concept produces a gas stream with a hydrogen content of more than 90 vol.% and without CO and CO2.

  2. Photoproduction of hydrogen - A potential system of solar energy bioconversion

    Energy Technology Data Exchange (ETDEWEB)

    Das, V S.R.

    1979-10-01

    The photoproduction of hydrogen from water utilizing the photosynthetic capacity of green plants is discussed as a possible means of solar energy conversion. Advantages of the biological production of H/sub 2/ over various physical and chemical processes are pointed out, and the system used for the production of hydrogen by biological agents, which comprises the photosynthetic electron transport chain, ferredoxin and hydrogenase, is examined in detail. The various types of biological hydrogen production systems in bacteria, algae, symbiotic systems and isolated chloroplast-ferredoxin-hydrogenase systems are reviewed. The limitations and the scope for further improvement of the promising symbiotic Azolli-Anabena azollae and chloroplast-ferredoxin-hydrogenase are discussed, and it is concluded that future research should concern itself with the identification of the environmental conditions that would maximize solar energy conversion efficiency, the elimination of the oxygen inhibition of biological hydrogen production, and the definition of the metabolic state for the maximal production of hydrogen.

  3. Introduction of hydrogen in the Norwegian energy system. NorWays - Regional model analysis

    Energy Technology Data Exchange (ETDEWEB)

    Rosenberg, Eva; Fidje, Audun; Espegren, Kari Aamodt

    2008-12-15

    The overall aim of the NorWays project has been to provide decision support for the introduction of hydrogen as an energy carrier in the Norwegian energy system. The NorWays project is a research project funded by the Research Council of Norway. An important task has been to develop alternative scenarios and identifying market segments and regions of the Norwegian energy system where hydrogen may play a significant role. The main scenarios in the project have been: Reference: Based on the assumptions of World Energy Outlook with no new transport technologies; HyWays: Basic assumptions with technology costs (H{sub 2}) based on results from the HyWays project; No tax: No taxes on transport energy ('revenue neutral'); CO{sub 2} reduction: Reduced CO{sub 2} emissions by 75% in 2050. Three regional models have been developed and used to analyse the introduction of hydrogen as energy carrier in competition with other alternatives such as natural gas, electricity, district heating and bio fuels.The focus of the analysis has been on the transportation sector. (Author)

  4. Detail Design of the hydrogen system and the gas blanketing system for the HANARO-CNS

    International Nuclear Information System (INIS)

    Choi, Jung Woon; Kim, Hark Rho; Kim, Young Ki; Wu, Sang Ik; Kim, Bong Su; Lee, Yong Seop

    2007-04-01

    The cold neutron source (CNS), which will be installed in the vertical CN hole of the reflector tank at HANARO, makes thermal neutrons to moderate into the cold neutrons with the ranges of 0.1 ∼ 10 meV passing through a moderator at about 22K. A moderator to produce cold neutrons is liquid hydrogen, which liquefies by the heat transfer with cryogenic helium flowing from the helium refrigeration system (HRS). Because of its installed location, the hydrogen system is designed to be surrounded by the gas blanketing system to notify the leakage on the system and to prevent hydrogen leakage out of the CNS. The hydrogen system, consisted of hydrogen charging unit, hydrogen storage unit, hydrogen buffer tank, and hydrogen piping, is designed to smoothly and safely supply hydrogen to and to draw back hydrogen from the IPA of the CNS under the HRS operation mode. Described is that calculation for total required hydrogen amount in the CNS as well as operation schemes of the hydrogen system. The gas blanketing system (GBS) is designed for the supply of the compressed nitrogen gas into the air pressurized valves for the CNS, to isolate the hydrogen system from the air and the water, and to prevent air or water intrusion into the vacuum system as well as the hydrogen system. All detail descriptions are shown inhere as well as the operation scheme for the GBS

  5. The Earth Observing System (EOS) nickel-hydrogen battery

    Science.gov (United States)

    Bennett, Charles W.

    1992-01-01

    Information is given in viewgraph form on the Earth Observing System (EOS) nickel hydrogen battery. Information is given on the life evaluation test, cell characteristics, acceptance and characterization tests, and the battery system description.

  6. Analysis of a multicomponent gas absorption system with carrier gas coabsorption

    International Nuclear Information System (INIS)

    Merriman, J.R.

    1975-03-01

    Conventional integrated versions of the packed gas absorber design equations do not account for significant coabsorption of the carrier gas along with the dilute transferring species. These equations, as a result, also neglect the relationship between dilute component transfer and carrier gas coabsorption. In the absorption of Kr and Xe from various carrier gases, using CCl 2 F 2 as the process solvent, carrier coabsorption is substantial. Consequently, a design package was developed to deal with multicomponent gas absorption in systems characterized by carrier gas coabsorption. Developed within the general film theory framework, the basic feature of this design approach is a view of dilute component mass-transfer as a conventional diffusive transfer superimposed on a net flux caused by carrier absorption. Other supporting elements of the design package include predictive techniques for various fluid properties, estimating procedures for carrier gas equilibrium constants, and correlations for carrier gas and dilute gas mass-transfer coefficients. When applied to systems using CCl 2 F 2 as the solvent; He, N 2 , air, or Ar as the carrier gas; and Kr or Xe as the dilute gas; the design approach gave good results, even when extended to conditions well beyond those of its development. (U.S.)

  7. Methods and systems for the production of hydrogen

    Science.gov (United States)

    Oh, Chang H [Idaho Falls, ID; Kim, Eung S [Ammon, ID; Sherman, Steven R [Augusta, GA

    2012-03-13

    Methods and systems are disclosed for the production of hydrogen and the use of high-temperature heat sources in energy conversion. In one embodiment, a primary loop may include a nuclear reactor utilizing a molten salt or helium as a coolant. The nuclear reactor may provide heat energy to a power generation loop for production of electrical energy. For example, a supercritical carbon dioxide fluid may be heated by the nuclear reactor via the molten salt and then expanded in a turbine to drive a generator. An intermediate heat exchange loop may also be thermally coupled with the primary loop and provide heat energy to one or more hydrogen production facilities. A portion of the hydrogen produced by the hydrogen production facility may be diverted to a combustor to elevate the temperature of water being split into hydrogen and oxygen by the hydrogen production facility.

  8. 78 FR 76391 - Proposed Enhancements to the Motor Carrier Safety Measurement System (SMS) Public Web Site

    Science.gov (United States)

    2013-12-17

    ...-0392] Proposed Enhancements to the Motor Carrier Safety Measurement System (SMS) Public Web Site AGENCY... proposed enhancements to the display of information on the Agency's Safety Measurement System (SMS) public Web site. On December 6, 2013, Advocates [[Page 76392

  9. A manual of recommended practices for hydrogen energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Hoagland, W.; Leach, S. [W. Hoagland and Associates, Boulder, CO (United States)

    1997-12-31

    Technologies for the production, distribution, and use of hydrogen are rapidly maturing and the number and size of demonstration programs designed to showcase emerging hydrogen energy systems is expanding. The success of these programs is key to hydrogen commercialization. Currently there is no comprehensive set of widely-accepted codes or standards covering the installation and operation of hydrogen energy systems. This lack of codes or standards is a major obstacle to future hydrogen demonstrations in obtaining the requisite licenses, permits, insurance, and public acceptance. In a project begun in late 1996 to address this problem, W. Hoagland and Associates has been developing a Manual of Recommended Practices for Hydrogen Systems intended to serve as an interim document for the design and operation of hydrogen demonstration projects. It will also serve as a starting point for some of the needed standard-setting processes. The Manual will include design guidelines for hydrogen procedures, case studies of experience at existing hydrogen demonstration projects, a bibliography of information sources, and a compilation of suppliers of hydrogen equipment and hardware. Following extensive professional review, final publication will occur later in 1997. The primary goal is to develop a draft document in the shortest possible time frame. To accomplish this, the input and guidance of technology developers, industrial organizations, government R and D and regulatory organizations and others will be sought to define the organization and content of the draft Manual, gather and evaluate available information, develop a draft document, coordinate reviews and revisions, and develop recommendations for publication, distribution, and update of the final document. The workshop, Development of a Manual of Recommended Practices for Hydrogen Energy Systems, conducted on March 11, 1997 in Alexandria, Virginia, was a first step.

  10. Rational construction of multiple interfaces in ternary heterostructure for efficient spatial separation and transfer of photogenerated carriers in the application of photocatalytic hydrogen evolution

    Science.gov (United States)

    Shi, Jian-Wen; Ma, Dandan; Zou, Yajun; Fan, Zhaoyang; Shi, Jinwen; Cheng, Linhao; Ji, Xin; Niu, Chunming

    2018-03-01

    The design of efficient and stable photocatalyst plays a critical role in the photocatalytic hydrogen evolution from water splitting. Herein, we develop a novel ZnS/CdS/ZnO ternary heterostructure by the in-situ sulfuration of CdS/ZnO, which includes four contact interfaces: CdS-ZnS interface, ZnS-ZnO interface, CdS-ZnO interface and ZnS-CdS-ZnO ternary interface, forming three charge carrier-transfer modes (type-I, type-II and direct Z-scheme) through five carrier-transfer pathways. As a result, the separation and transfer of photoexcited electron-hole pairs are promoted significantly, resulting in a high hydrogen evolution rate of 44.70 mmol h-1 g-1, which is 2, 3.7 and 8 times higher than those of binary heterostructures, CdS/ZnO, CdS/ZnS and ZnS/ZnO, respectively, and 26.5, 280 and 298 times higher than those of single CdS, ZnO and ZnS, respectively. As a counterpart ternary heterostructure, CdS/ZnS/ZnO contains only two interfaces: CdS-ZnS interface and ZnS-ZnO interface, which form two charge carrier-transfer modes (type-I and type-II) through two carrier-transfer pathways, leading to its much lower hydrogen evolution rate (27.25 mmol h-1 g-1) than ZnS/CdS/ZnO ternary heterostructure. This work is relevant for understanding the charge-transfer pathways between multi-interfaces in multicomponent heterojunctions.

  11. 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.

  12. Automatic carrier acquisition system for phase-lock-loop receivers

    Science.gov (United States)

    Bunce, R. C.

    1973-01-01

    Programmable oscillator and zero-beat detector acquires phase-lock of carrier by frequency scanning. Generation of high-level dc pulse at instant of zero crossing provides positive trigger for decision gate to stop search and close loop for phase-coherent tracking.

  13. Direct-hydrogen-fueled proton-exchange-membrane fuel cell system for transportation applications. Hydrogen vehicle safety report

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, C.E. [Directed Technologies, Inc., Arlington, VA (United States)

    1997-05-01

    This report reviews the safety characteristics of hydrogen as an energy carrier for a fuel cell vehicle (FCV), with emphasis on high pressure gaseous hydrogen onboard storage. The authors consider normal operation of the vehicle in addition to refueling, collisions, operation in tunnels, and storage in garages. They identify the most likely risks and failure modes leading to hazardous conditions, and provide potential countermeasures in the vehicle design to prevent or substantially reduce the consequences of each plausible failure mode. They then compare the risks of hydrogen with those of more common motor vehicle fuels including gasoline, propane, and natural gas.

  14. Vectorization of agrochemicals: amino acid carriers are more efficient than sugar carriers to translocate phenylpyrrole conjugates in the Ricinus system.

    Science.gov (United States)

    Wu, Hanxiang; Marhadour, Sophie; Lei, Zhi-Wei; Yang, Wen; Marivingt-Mounir, Cécile; Bonnemain, Jean-Louis; Chollet, Jean-François

    2018-05-01

    Producing quality food in sufficient quantity while using less agrochemical inputs will be one of the great challenges of the twenty-first century. One way of achieving this goal is to greatly reduce the doses of plant protection compounds by improving the targeting of pests to eradicate. Therefore, we developed a vectorization strategy to confer phloem mobility to fenpiclonil, a contact fungicide from the phenylpyrrole family used as a model molecule. It consists in coupling the antifungal compound to an amino acid or a sugar, so that the resulting conjugates are handled by active nutrient transport systems. The method of click chemistry was used to synthesize three conjugates combining fenpiclonil to glucose or glutamic acid with a spacer containing a triazole ring. Systemicity tests with the Ricinus model have shown that the amino acid promoiety was clearly more favorable to phloem mobility than that of glucose. In addition, the transport of the amino acid conjugate is carrier mediated since the derivative of the L series was about five times more concentrated in the phloem sap than its counterpart of the D series. The systemicity of the L-derivative is pH dependent and almost completely inhibited by the protonophore carbonyl cyanide 3-chlorophenylhydrazone (CCCP). These data suggest that the phloem transport of the L-derivative is governed by a stereospecific amino acid carrier system energized by the proton motive force.

  15. Integrated Renewable Hydrogen Utility System (IRHUS) business plan

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-03-01

    This business plan is for a proposed legal entity named IRHUS, Inc. which is to be formed as a subsidiary of Energy Partners, L.C. (EP) of West Palm Beach, Florida. EP is a research and development company specializing in hydrogen proton exchange membrane (PEM) fuel cells and systems. A fuel cell is an engine with no moving parts that takes in hydrogen and produces electricity. The purpose of IRHUS, Inc. is to develop and manufacture a self-sufficient energy system based on the fuel cell and other new technology that produces hydrogen and electricity. The product is called the Integrated renewable Hydrogen utility System (IRHUS). IRHUS, Inc. plans to start limited production of the IRHUS in 2002. The IRHUS is a unique product with an innovative concept in that it provides continuous electrical power in places with no electrical infrastructure, i.e., in remote and island locations. The IRHUS is a zero emissions, self-sufficient, hydrogen fuel generation system that produces electricity on a continuous basis by combining any renewable power source with hydrogen technology. Current plans are to produce a 10 kilowatt IRHUS MP (medium power). Future plans are to design and manufacture IRHUS models to provide power for a variety of power ranges for identified attractive market segments. The technological components of the IRHUS include an electrolyzer, hydrogen and oxygen storage subsystems, fuel cell system, and power control system. The IRHUS product is to be integrated with a variety of renewable energy technologies. 5 figs., 10 tabs.

  16. Development of interface technology for nuclear hydrogen production system

    International Nuclear Information System (INIS)

    Lee, Ki Young; Park, J. K.; Chang, J. H.

    2012-06-01

    These works focus on the development of attainment indices for nuclear hydrogen key technologies, the analysis of the hydrogen production process and the performance estimation for hydrogen production systems, and the assessment of the nuclear hydrogen production economy. The codes for analyzing the hydrogen production economy are developed for calculating the unit production cost of nuclear hydrogen. We developed basic R and D quality management methodology to meet design technology of VHTR's needs. By putting it in practice, we derived some problems and solutions. We distributed R and D QAP and Q and D QAM to each teams and these are in operation. Computer simulations are performed for estimating the thermal efficiency for the electrodialysis component likely to adapting as one of the hydrogen production system in Korea and EED-SI process known as the key components of the hydrogen production systems. Using the commercial codes, the process diagrams and the spread-sheets were produced for the Bunsen reaction process, Sulphuric Acid dissolution process and HI dissolution process, respectively, which are the key components composing of the SI process

  17. Liquid hydrogen transfer pipes and level regulation systems

    International Nuclear Information System (INIS)

    Marquet, M.; Prugne, P.; Roubeau, P.

    1961-01-01

    Describes: 1) Transfer pipes - Plunging rods in liquid hydrogen Dewars; transfer pipes: knee-joint system for quick and accurate positioning of plunging Dewar rods; system's rods: combined valve and rod; valves are activated either by a bulb pressure or by a solenoid automatically or hand controlled. The latter allows intermittent filling. 2) Level regulating systems: Level bulbs: accurate to 1 or 4 m; maximum and minimum level bulbs: automatic control of the liquid hydrogen valve. (author) [fr

  18. Management of Leaks in Hydrogen Production, Delivery, and Storage Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rawls, G

    2006-04-27

    A systematic approach to manage hydrogen leakage from components is presented. Methods to evaluate the quantity of hydrogen leakage and permeation from a system are provided by calculation and testing sensitivities. The following technology components of a leak management program are described: (1) Methods to evaluate hydrogen gas loss through leaks; (2) Methods to calculate opening areas of crack like defects; (3) Permeation of hydrogen through metallic piping; (4) Code requirements for acceptable flammability limits; (5) Methods to detect flammable gas; (6) Requirements for adequate ventilation in the vicinity of the hydrogen system; (7) Methods to calculate dilution air requirements for flammable gas mixtures; and (8) Concepts for reduced leakage component selection and permeation barriers.

  19. Conceptual design of hydrogen isotopes chromatographic separation system with super large capacity

    International Nuclear Information System (INIS)

    Xie Bo; Weng Kuiping; Liu Yunnu; Hou Jianping

    2012-01-01

    A super large capacity hydrogen isotopes separation system, including total plan, unit (including making and purification of gas, three-grade chromatographic columns, gas loop and auto-control, and carrier recovery) and experimental scheme, had been designed on the basis of a series of hydrogen-deuterium experiments by temperature programmed de- sorption. The characteristic of the system was that desorption kinetic parameters could be directly calculated from the hydrogen isotope separation desorption spectra information. In other words, the complicated dynamic process of separation could be described by the desorption rate equation, shape parameter and desorption activation energy calculation on the condition of the experimental data and appropriate assumptions (equilibrium and adsorption, uniform surface). In previous work, an experimental series of operation to verify the successive enrichment of D 2 from a H 2 -D 2 mixture, the production of the deuterium from natural hydrogen and the recovery of tritium such as from the nuclear heavy-water were carried out using MS5A at 77 K. This work was only conceptual design, so it was necessary to identify the availability of super large capacity system by experiment. (authors)

  20. Standard-B Hydrogen Monitoring System, system design description

    International Nuclear Information System (INIS)

    Schneider, T.C.

    1995-01-01

    During most of the year, it is assumed that the vapor in the 177 radioactive waste tanks on the Hanford Project site contain a uniform mixture of gases. Several of these waste tanks (currently twenty five, 6 Double Shell Tanks and 19 Single Shell Tanks) were identified as having the potential for the buildup of gases to a flammable level. An active ventilation system in the Double Shell Tanks and a passive ventilation system in the Single Shell Tanks provides a method of expelling gases from the tanks. A gas release from a tank causes a temporary rise in the tank pressure, and a potential for increased concentration of hydrogen gas in the vapor space. The gas is released via the ventilation systems until a uniform gas mixture in the vapor space is once again achieved. This document describes the design of the Standard-B Hydrogen Monitoring System, (SHMS) and its components as it differs from the original SHMS. The differences are derived from changes made to improve the system performance but not implemented in all the installed enclosures

  1. Conceptual design of the HTTR-IS hydrogen production system

    International Nuclear Information System (INIS)

    Sakaba, Nariaki; Sato, Hiroyuki; Hara, Teruo; Kato, Ryoma; Ohashi, Kazutaka; Nishihara, Tetsuo; Kunitomi, Kazuhiko

    2007-08-01

    Since hydrogen produced by nuclear should be economically competitive compared with other methods in a hydrogen society, it is important to build hydrogen production system to be coupled with the reactor as a conventional chemical plant. Japan Atomic Energy Agency started the safety study to establish a new safety philosophy to meet safety requirements for non-nuclear grade hydrogen production system. Also, structural concepts with integrating functions for the Bunsen reactor and sulphuric acid decomposer were proposed to reduce construction cost of the IS process hydrogen production system. In addition, HI decomposer which enables the process condition to be eased consisting of conventional materials and technologies was studied. Moreover, technical feasibility of the HTTR-IS system in which the hydrogen production rate of 1,000 Nm 3 /h by using the supplied heat of 10 MW from the intermediate heat exchanger of the HTTR was confirmed. This paper describes the conceptual design of the HTTR-IS hydrogen production system. (author)

  2. Hydrogen Production from Optimal Wind-PV Energies Systems

    Energy Technology Data Exchange (ETDEWEB)

    Tafticht, T.; Agbossou, K. [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

    2006-07-01

    Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

  3. Hydrogen Production from Optimal Wind-PV Energies Systems

    International Nuclear Information System (INIS)

    T Tafticht; K Agbossou

    2006-01-01

    Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

  4. Hydrogen Production from Optimal Wind-PV Energies Systems

    International Nuclear Information System (INIS)

    Tafticht, T.; Agbossou, K.

    2006-01-01

    Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyser, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

  5. Hydrogen Production from Optimal Wind-PV Energies Systems

    Energy Technology Data Exchange (ETDEWEB)

    T Tafticht; K Agbossou [Institut de recherche sur l hydrogene, Universite du Quebec - Trois-Rivieres, C.P. 500, Trois-Rivieres, (Ciheam), G9A 5H7, (Canada)

    2006-07-01

    Electrolytic hydrogen offers a promising alternative for long-term energy storage of renewable energies (RE). A stand-alone RE system based on hydrogen production has been developed at the Hydrogen Research Institute and successfully tested for automatic operation with designed control devices. The system is composed of a wind turbine, a photovoltaic (PV) array, an electrolyzer, batteries for buffer energy storage, hydrogen and oxygen storage tanks, a fuel cell, AC and DC loads, power conditioning devices and different sensors. The long-term excess energy with respect to load demand has been sent to the electrolyser for hydrogen production and then the fuel cell has utilised this stored hydrogen to produce electricity when there were insufficient wind and solar energies with respect to load requirements. The RE system components have substantially different voltage-current characteristics and they are integrated on the DC bus through power conditioning devices for optimal operation by using the developed Maximum Power Point Tracking (MPPT) control method. The experimental results show that the power gain obtained by this method clearly increases the hydrogen production and storage rate from wind-PV systems. (authors)

  6. Technoeconomic analysis of renewable hydrogen production, storage, and detection systems

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.K.; Spath, P.L.; Kadam, K. [National Renewable Energy Lab., Golden, CO (United States)

    1996-10-01

    Technical and economic feasibility studies of different degrees of completeness and detail have been performed on several projects being funded by the Department of Energy`s Hydrogen Program. Work this year focused on projects at the National Renewable Energy Laboratory, although analyses of projects at other institutions are underway or planned. Highly detailed analyses were completed on a fiber optic hydrogen leak detector and a process to produce hydrogen from biomass via pyrolysis followed by steam reforming of the pyrolysis oil. Less detailed economic assessments of solar and biologically-based hydrogen production processes have been performed and focused on the steps that need to be taken to improve the competitive position of these technologies. Sensitivity analyses were conducted on all analyses to reveal the degree to which the cost results are affected by market changes and technological advances. For hydrogen storage by carbon nanotubes, a survey of the competing storage technologies was made in order to set a baseline for cost goals. A determination of the likelihood of commercialization was made for nearly all systems examined. Hydrogen from biomass via pyrolysis and steam reforming was found to have significant economic potential if a coproduct option could be co-commercialized. Photoelectrochemical hydrogen production may have economic potential, but only if low-cost cells can be modified to split water and to avoid surface oxidation. The use of bacteria to convert the carbon monoxide in biomass syngas to hydrogen was found to be slightly more expensive than the high end of currently commercial hydrogen, although there are significant opportunities to reduce costs. Finally, the cost of installing a fiber-optic chemochromic hydrogen detection system in passenger vehicles was found to be very low and competitive with alternative sensor systems.

  7. Design tool for offgrid hydrogen refuelling systems for aerospace applications

    International Nuclear Information System (INIS)

    Troncoso, E.; Lapeña-Rey, N.; Gonzalez, M.

    2016-01-01

    Highlights: • A simulation tool for offgrid CPV-based hydrogen refuelling systems is presented. • Simulations of system configurations with specific UAS hydrogen demand scenarios. • Regarding system size & reliability the most critical components are the CPV array and batteries. • In terms of energy efficiency the most critical component is the electrolyser. - Abstract: To develop an environmentally acceptable refuelling solution for fuel cell-powered unmanned aerial systems (UASs) to operate in remote areas, hydrogen fuel must be produced on-site from renewable energy sources. This paper describes a Matlab-based simulation tool specifically developed to pre-design offgrid hydrogen refuelling systems for UAS applications. The refuelling system comprises a high concentrated PV array (CPV), an electrolyser, a hydrogen buffer tank and a diaphragm hydrogen compressor. Small composite tanks are also included for fast refuelling of the UAV platforms at any time during the year. The novel approach of selecting a CPV power source is justified on the basis of minimizing the system footprint (versus flat plat or low concentration PV), aiming for a containerized remotely deployable UAS offgrid refuelling solution. To validate the simulation tool a number of simulations were performed using experimental data from a prototype offgrid hydrogen refuelling station for UAVs developed by Boeing Research & Technology Europe. Solar irradiation data for a selected location and daily UAS hydrogen demands of between 2.8 and 15.8 Nm"3 were employed as the primary inputs, in order to calculate a recommended system sizing solution and assess the expected operation of the refuelling system across a given year. The specific energy consumption of the refuelling system obtained from the simulations is between 5.6 and 8.9 kW h_e per kg of hydrogen delivered to the UAVs, being lower for larger daily hydrogen demands. Increasing the CPV area and electrolyser size in order to supply higher

  8. Research and development of HTTR hydrogen production systems

    International Nuclear Information System (INIS)

    Shiozawa, Shusaku; Ogawa, Masuro; Inagaki, Yoshiyuki; Onuki, Kaoru; Takeda, Tetsuaki; Nishihara, Tetsuo; Hayashi, Koji; Kubo, Shinji; Inaba, Yoshitomo; Ohashi, Hirofumi

    2002-01-01

    The Japan Atomic Energy Research Institute (JAERI) has constructed the High Temperature Engineering Test Reactor (HTTR) with a thermal output of 30MW and a reactor out let coolant temper at ure of 950 .deg. C. There search and development (R and D) program on nuclear production of hydrogen was started on January in 1997 as a study consigned by Ministry of Education, Culture, Sports, Science and Technology. A hydrogen production system connected to the HTTR is being designed to be able to produce hydrogen of about 4000m 3 /h by steam reforming of natural gas, using a nuclear heat of 10MW supplied by the HTTR hydrogen production system. In order to confirm controllability, safety and performance of key components in the HTTR hydrogen production system, the facility for the out-of-pile test was constructed on the scale of approximately 1/30 of the HTTR hydrogen production system. In parallel to the out-of-pile test, the following tests as essential problem, a corrosion test of a reforming tube, a permeation test of hydrogen isotopes through heat exchanger and reforming tubes, and an integrity test of a high-temperature isolation valve are carried out to obtain detailed data for safety review and development of analytical codes. Other basis studies on the hydrogen production technology of thermochemical water splitting called an iodine sulfur (IS) process, has been carried out for more effective and various uses of nuclear heat. This paper describes the present status and a future plan on the R and D of the HTTR hydrogen production systems in JAERI

  9. Solar Hydrogen Energy Systems Science and Technology for the Hydrogen Economy

    CERN Document Server

    Zini, Gabriele

    2012-01-01

    It is just a matter of time when fossil fuels will become unavailable or uneconomical to retrieve. On top of that, their environmental impact is already too severe. Renewable energy sources can be considered as the most important substitute to fossil energy, since they are inexhaustible and have a very low, if none, impact on the environment. Still, their unevenness and unpredictability are drawbacks that must be dealt with in order to guarantee a reliable and steady energy supply to the final user. Hydrogen can be the answer to these problems. This book presents the readers with the modeling, functioning and implementation of solar hydrogen energy systems, which efficiently combine different technologies to convert, store and use renewable energy. Sources like solar photovoltaic or wind, technologies like electrolysis, fuel cells, traditional and advanced hydrogen storage are discussed and evaluated together with system management and output performance. Examples are also given to show how these systems are ...

  10. Cold weather hydrogen generation system and method of operation

    Science.gov (United States)

    Dreier, Ken Wayne; Kowalski, Michael Thomas; Porter, Stephen Charles; Chow, Oscar Ken; Borland, Nicholas Paul; Goyette, Stephen Arthur

    2010-12-14

    A system for providing hydrogen gas is provided. The system includes a hydrogen generator that produces gas from water. One or more heat generation devices are arranged to provide heating of the enclosure during different modes of operation to prevent freezing of components. A plurality of temperature sensors are arranged and coupled to a controller to selectively activate a heat source if the temperature of the component is less than a predetermined temperature.

  11. Meeting report - Which role for hydrogen in the energy system?

    International Nuclear Information System (INIS)

    Dupre La Tour, Stephane; Raimondo, E.

    2015-01-01

    Before giving some general information about the activities of the SFEN, about some events regarding the energy sector, and about meetings to come, a contribution is proposed on the role of hydrogen in the energy system. The author recalls the industrial methods used to produce hydrogen (water electrolysis, reforming of fossil fuels), indicates the main applications (fuel cells, power-to-gas, industrial applications, fuel for transport). He discusses the potential of hydrogen as a good energy vector for the future. Required technical advances are identified, as well as potential industrial applications. The competitiveness of the different hydrogen production technologies is discussed, and the different uses are more precisely described and discussed (principle of fuel cell, French researches on hybrid vehicle, application to heavy vehicles, perspectives for air transport). Other technological issues are briefly addressed: direct injection of hydrogen in gas distribution network or production of synthetic methane, combined hydrolysis of CO 2 and H 2 O, hydrogen storage. After having outlined some remaining questions about the exploitation of hydrogen as energy vector, the author proposes some guidelines for the future: development of tools to analyse the competitiveness of hydrogen uses, improvement of existing technologies in terms of performance and costs, development of breakthrough technologies

  12. Development and characterization of a solar-hydrogen energy system

    International Nuclear Information System (INIS)

    Sebastian, P.J.; Vejar, S.; Gonzalez, E.; Perez, M.; Gamboa, S.A.

    2009-01-01

    'Full text': The details of the development of a PV-hydrogen hybrid energy system are presented. An arrangement of photovoltaic modules (125 W/module) was established to provide 9 kW installed power in a three-phase configuration at 127 Vrms/phase. A 5 kW fuel cell system (hydrogen/oxygen) operates as a dynamic backup of the photovoltaic system. The autonomous operation of the hybrid power system implies the production of hydrogen by electrolysis. The hydrogen is produced by water electrolysis using an electrolyzer of 1 kW of power. The electrical energy used to produce hydrogen is supplied from solar panels by using 1 kW of photovoltaic modules. The photovoltaic modules are installed in a sun-tracker arrangement for increasing the energy conversion efficiency. The hydrogen is stored in solar to electric commercial metal hydride based containers and supplied to the fuel cell. The hybrid system is monitored by internet, and some dynamic characteristics such as demanding power, energy and power factor could be analyzed independently from the system. Some energy saving recommendations have been implemented as a pilot program at CIE-UNAM to improve the efficient use of clean energy in normal operating conditions in offices and laboratories. (author)

  13. Development of a solar-hydrogen hybrid energy system

    International Nuclear Information System (INIS)

    Sebastian, P.J.; Gamboa, S.A.; Vejar, Set; Campos, J.

    2009-01-01

    Full text: The details of the development of a PV-hydrogen hybrid energy system is presented. An arrangement of photovoltaic modules (125 W/module) was established to provide 9 kW installed power in a three-phase configuration at 127 Vrms/phase. A 5 kW fuel cell system (hydrogen/oxygen) operate as a dynamic backup of the photovoltaic system. The autonomous operation of the hybrid power system implies the production of hydrogen by electrolysis. The hydrogen is produced by water electrolysis using an electrolyzer of 1 kW power. The electrical energy used to produce hydrogen is supplied from solar panels by using 1kW of photovoltaic modules. The photovoltaic modules are installed in a sun-tracker arrangement for increasing the energy conversion efficiency. The hydrogen is stored in solar to electric commercial metal hydride based containers and supplied to the fuel cell. The hybrid system is monitored by internet and some dynamic characteristics such as demanding power, energy and power factor could be analyzed independently from the system. Some energy saving recommendations has been implemented as a pilot program at CIE-UNAM to improve the efficient use of clean energy in normal operating conditions in offices and laboratories. (author)

  14. Unmanned Carrier-Based Aircraft System: Debate over Systems Role Led to Focus on Aerial Refueling

    Science.gov (United States)

    2016-03-24

    Unmanned Carrier-Based Aircraft System: Debate over System’s Role Led to Focus on Aerial Refueling Prior to February 2016, the Navy had planned to...Background In a May 2015 report, we found that the intended mission and required capabilities of UCLASS were under review as there was debate ...environments, or largely strike with limited surveillance capability operating in highly contested environments.2 This debate delayed the expected

  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. A study of wind hydrogen production of systems for Malaysia

    International Nuclear Information System (INIS)

    Ibrahim, M.Z.; Kamaruzzaman Sopian; Wan Ramli Wan Daud; Othman, M.Y.; Baharuddin Yatim; Veziroglu, T.N.

    2006-01-01

    Recently, Malaysia is looking into the potential of using hydrogen as future fuel. By recognizing the potential of hydrogen fuel, the government had channeled a big amount of money in funds to related organizations to embark on hydrogen research and development programmed. The availability of indigenous renewable resources, high trade opportunities, excellent research capabilities and current progress in hydrogen research at the university are some major advantages for the country to attract government and industry investment in hydrogen. It is envisaged that overall energy demand in Malaysia as stated in the Eighth Malaysia Plan (EMP) report will increase by about 7.8 percent per annum in this decade at the present economic growth. Considering the vast potential inherent in renewable energy (RE), it could be a significant contributor to the national energy supply. Malaysia had been blessed with abundant and varied resources of energy, nevertheless, concerted efforts should be undertaken to ensure that the development of energy resources would continue to contribute to the nation's economic expansion. In this regard, an initial study has been carried out to see the available potential of wind energy towards the hydrogen production, that could be utilized in various applications particularly in Malaysian climate condition via a computer simulation (HYDROGEMS), which built for TRNSYS (a transient system simulation program) version 15. The system simulated in this study consist of one unit (1 kW) wind turbine, an electrolyze (1 kW), a hydrogen (H 2 ) storage tank, and a power conditioning system. A month hourly data of highest wind speed is obtained from the local weather station that is at Kuala Terengganu Air Port located at 5''o 23'' latitude (N) and 103''o 06'' Longitude (E). The results show, wind energy in Malaysian Climate has a potential to generate hydrogen with the minimum rate approximately 9 m 3 /hr and storage capacity of 60 Nm 3 , State of Charge (SOC

  17. New perspectives on renewable energy systems based on hydrogen

    International Nuclear Information System (INIS)

    Bose, T. K.; Agbossou, K.; Benard, P.; St-Arnaud, J-M.

    1999-01-01

    Current hydrocarbon-based energy systems, current energy consumption and the push towards the utilization of renewable energy sources, fuelled by global warming and the need to reduce atmospheric pollution are discussed. The consequences of climatic change and the obligation of Annex B countries to reduce their greenhouse gas emissions in terms of the Kyoto Protocols are reviewed. The role that renewable energy sources such as hydrogen, solar and wind energy could play in avoiding the most catastrophic consequences of rapidly growing energy consumption and atmospheric pollution in the face of diminishing conventional fossil fuel resources are examined. The focus is on hydrogen energy as a means of storing and transporting primary energy. Some favorable characteristics of hydrogen is its abundance, the fact that it can be produced utilizing renewable or non-renewable sources, and the further fact that its combustion produces three times more energy per unit of mass than oil, and six times more than coal. The technology of converting hydrogen into energy, storing energy in the form of hydrogen, and its utilization, for example in the stabilization of wind energy by way of electrolytic conversion to hydrogen, are described. Development at Hydro-Quebec's Institute of Research of a hydrogen-based autonomous wind energy system to produce electricity is also discussed. 2 tabs., 11 refs

  18. PNNL Development and Analysis of Material-Based Hydrogen Storage Systems for the Hydrogen Storage Engineering Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Kriston P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Alvine, Kyle J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Kenneth I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Klymyshyn, Nicholas A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pires, Richard P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ronnebro, Ewa [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Simmons, Kevin L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weimar, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westman, Matthew P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-02-29

    The Hydrogen Storage Engineering Center of Excellence is a team of universities, industrial corporations, and federal laboratories with the mandate to develop lower-pressure, materials-based, hydrogen storage systems for hydrogen fuel cell light-duty vehicles. Although not engaged in the development of new hydrogen storage materials themselves, it is an engineering center that addresses engineering challenges associated with the currently available hydrogen storage materials. Three material-based approaches to hydrogen storage are being researched: 1) chemical hydrogen storage materials 2) cryo-adsorbents, and 3) metal hydrides. As a member of this Center, Pacific Northwest National Laboratory (PNNL) has been involved in the design and evaluation of systems developed with each of these three hydrogen storage materials. This report is a compilation of the work performed by PNNL for this Center.

  19. Analysis of hydrogen operation in the Danish Traffic System

    DEFF Research Database (Denmark)

    Jørgensen, Kaj

    1996-01-01

    The main report of a study of the utilisation of hydrogen in the Danish energy and traffic system.The report contains an overview and assessment of the potential hydrogen technologies as well as analyses of the energy and environmental effects of different applications in the Danish transport sec...... sector (passenger car, bus, van, truck). The report concludes that hydrogen along with electric and hybrid propulsion can be a very interesting element in a strategy for sustainable transport, but only if based mainly on renewable energy....

  20. 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)

  1. 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)

  2. The Hydrogen Detection Technique for SG Protection System

    International Nuclear Information System (INIS)

    Lv Mingyu; Pei Zhiyong; Yu Huajin

    2015-01-01

    SG that is pressure boundary between secondary loop and triple loop is the key equipment of fast reactor, in which heat in secondary loop is transferred to water or steam in triple loop. According to data from IAEA, SG is the highest failure rate equipment in fast reactor, especially because of failure of heat transfer tube. In order to monitor failure of heat transfer tube, Fast Reactor Engineering Department develops diffusion type hydrogen detection system, which is used to detect sodium-water reaction in time. This paper firstly introduces experimental research scheme and results of this hydrogen detection technique; Subsequently, it is described that how this technique can be engineering realized in CEFR; Moreover, through developing a series of calibration tests and hydrogen injection tests, it is obtained that sensitivity, response time and calibration curse for hydrogen detection system of CEFR. (author)

  3. System level permeability modeling of porous hydrogen storage materials.

    Energy Technology Data Exchange (ETDEWEB)

    Kanouff, Michael P.; Dedrick, Daniel E.; Voskuilen, Tyler (Purdue University, West Lafayette, IN)

    2010-01-01

    A permeability model for hydrogen transport in a porous material is successfully applied to both laboratory-scale and vehicle-scale sodium alanate hydrogen storage systems. The use of a Knudsen number dependent relationship for permeability of the material in conjunction with a constant area fraction channeling model is shown to accurately predict hydrogen flow through the reactors. Generally applicable model parameters were obtained by numerically fitting experimental measurements from reactors of different sizes and aspect ratios. The degree of channeling was experimentally determined from the measurements and found to be 2.08% of total cross-sectional area. Use of this constant area channeling model and the Knudsen dependent Young & Todd permeability model allows for accurate prediction of the hydrogen uptake performance of full-scale sodium alanate and similar metal hydride systems.

  4. Hydrogenic systems for calculable frequency standards. Status and options

    International Nuclear Information System (INIS)

    Flowers, J.; Klein, H.; Knight, D.

    2001-01-01

    The study of hydrogen and hydrogenic (one-electron) ions is an area of rapid progress and one of great potential for future frequency standards. In 1997, the two-photon 1S-2S transition in the hydrogen atom was included in the list of approved radiations for the practical realisation of the metre, and since then revolutions in optical frequency metrology have reduced the uncertainty in its frequency by more than an order of magnitude, to 1.8 parts in 10 14 . Hydrogenic systems are simple enough that the frequencies of their transitions can be calculated in terms of the Rydberg constant with an accuracy that can approach or exceed the measurement uncertainty. Transitions in such systems can be thought of as forming a natural frequency scale, and offer the prospect of a set of quantum frequency standards which are directly related to the fundamental constants. The Rydberg constant is currently best determined from optical frequency measurements in hydrogen. However, to take full advantage of the recent high accuracy 1S-2S frequency measurement requires: Improved measurements of other transition frequencies in the hydrogen atom; Reduced uncertainty in the quantum electrodynamic (QED) contributions to the energy levels, in particular the two-loop binding corrections; An improved value for the proton charge radius. In He + and one-electron systems of higher atomic number Z, the two-loop binding corrections are a fractionally larger part of the Lamb shift due to their rapid scaling with Z. Measurements of the Lamb shift in medium-Z hydrogenic ions can therefore provide tests of these corrections, and feed in to the theoretical understanding of hydrogen itself Although both theory and experiment are less accurate at higher Z, there is the potential for a new range of X-ray standards, providing that the QED corrections are well understood and new absolute measurement techniques can be developed. A number of areas are suggested for future investigation: Improving the

  5. Understanding interparticle interactions in dry powder inhalation : glass beads as an innovative model carrier system

    OpenAIRE

    Renner, Niklas Ludwig

    2017-01-01

    Delivery of drugs via the pulmonary route is the most common approach to treat diseases of the respiratory system, e.g. asthma bronchiale. Here, the active pharmaceutical ingredient is generally formulated in a so-called interactive mixture with a coarse and inert carrier. This enhances flowability and therefore dose metering and dispersibility. Interparticle interactions between carrier and drug govern aerosolisation behaviour of the blend and consequently the efficacy of the drug deposition...

  6. A system of hydrogen powered vehicles with liquid organic hydrides

    International Nuclear Information System (INIS)

    Taube, M.

    1981-07-01

    A motor car system based on the hydrogen produced by nuclear power stations during the night in the summer, and coupled with organic liquid hydride seems to be a feasible system in the near future. Such a system is discussed and the cost is compared with gasoline. (Auth.)

  7. CATALYTICALLY ENHANCED SYSTEMS FOR HYDROGEN STORAGE. Final report

    International Nuclear Information System (INIS)

    Craig M. Jensen

    2007-01-01

    Previous U.S. DOE sponsored research at the University of Hawaii resulted in the development of methods of doping of sodium aluminum hydride, NaAlH4 with titanium, zirconium and other catalysts such that: dehydriding occurs at temperatures as low as 100 C; rehydriding requires less than 1 h; and >4 weight percent hydrogen can be repeatedly cycled through dehydriding/rehydriding. These materials appeared to be on the threshold of practical viability as hydrogen carriers for onboard fuel cells. However, it was apparent that further kinetic enhancement was required to achieve commercial viability. Thus, one of the primary goals of this project was to develop the requisite improved catalysts. Over the course of this project, a variety of titanium and zirconium dopant precursors were investigated. Moreover, the approach was to conduct guided search for improved catalysts by obtaining a fundamental understanding of the chemical nature of the titanium dopants and their mechanism of action. Therefore, the projected also aimed to determined the chemical nature of the titanium species that are formed upon mechanical milling of NaAlH4 with the dopant precursors through synchrotron X-ray and neutron diffraction as well as transmission electron microscopy, scanning electron microscopy, and electron paramagnetic resonance (EPR) spectroscopy. In addition to kinetic studies, insight into the mechanism of action of the dopants was gained through studies of the destabilization of hydrogen in NaAlH4 by the dopants through infrared, NMR, and anelastic spectroscopy

  8. Generation IV nuclear energy systems and hydrogen economy. New progress in the energy field in the 21st century

    International Nuclear Information System (INIS)

    Zang Mingchang

    2004-01-01

    The concept of hydrogen economy was initiated by the United States and other developed countries in the turn of the century to mitigate anxiety of national security due to growing dependence on foreign sources of energy and impacts on air quality and the potential effects of greenhouse gas emissions. Hydrogen economy integrates the primary energy used to produce hydrogen as a future energy carrier, hydrogen technologies including production, delivery and storage, and various fuel cells for transportation and stationary applications. A new hydrogen-based energy system would created as an important solution in the 21st century, flexible, affordable, safe, domestically produced, used in all sectors of the economy and in all regions of the country, if all the R and D plans and the demonstration come to be successful in 20-30 years. Among options of primary energy. Generation IV nuclear energy under development is particularly well suited to hydrogen production, offering the competitive position of large-scale hydrogen production with near-zero emissions. (author)

  9. 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)

  10. Hydrogen based energy storage for solar energy systems

    Energy Technology Data Exchange (ETDEWEB)

    Vanhanen, J.P.; Hagstroem, M.T.; Lund, P.H. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Engineering Physics and Mathematics; Leppaenen, J.R.; Nieminen, J.P. [Neste Oy (Finland)

    1998-12-31

    Hydrogen based energy storage options for solar energy systems was studied in order to improve their overall performance. A 1 kW photovoltaic hydrogen (PV-H2) pilot-plant and commercial prototype were constructed and a numerical simulation program H2PHOTO for system design and optimisation was developed. Furthermore, a comprehensive understanding of conversion (electrolysers and fuel cells) and storage (metal hydrides) technologies was acquired by the project partners. The PV-H{sub 2} power system provides a self-sufficient solution for applications in remote locations far from electric grids and maintenance services. (orig.)

  11. Long-term transition to power/hydrogen energy system based on regenerative energy sources. Langfristiger Uebergang zum Strom/Wasserstoff-Energiesystem auf der Basis erneuerbarer Energiequellen

    Energy Technology Data Exchange (ETDEWEB)

    Wurster, R

    1989-01-01

    If we mean to secure the future of this planet in its present state we shall have to reduce drastically the emissions of trace gases influencing our climate like CO/sub 2/, CH/sub 4/, FCHC, ozone, N/sub 2/O and stratospheric H/sub 2/O. CO/sub -/neutral energy sources in clude nuclear energy and regenerative energies (solar, wind, water, biomass, tidal energy). These energy sources provide energy carriers in terms of electricity, heat, biofuels, synthesis gas and hydrogen. The author discusses the power/hydrogen energy system, electrolytic generation of hydrogen and its capacity for storage and transport from sunny solar-energy utilization areas (Central Africa). Hydrogen can then be used in drive systems, power generation (power stations) and for space heating and process heat. The author discusses its profitability and underlines the fact that hydrogen will figure in the energy economy of the future. (HWJ).

  12. Standard-E hydrogen monitoring system shop acceptance test procedure

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, T.C.

    1997-10-02

    The purpose of this report is to document that the Standard-E Hydrogen Monitoring Systems (SHMS-E), fabricated by Mid-Columbia Engineering (MCE) for installation on the Waste Tank Farms in the Hanford 200 Areas, are constructed as intended by the design. The ATP performance will verify proper system fabrication.

  13. Standard-E hydrogen monitoring system shop acceptance test report

    International Nuclear Information System (INIS)

    Schneider, T.C.

    1997-01-01

    The purpose of this report is to document that the Standard-E Hydrogen Monitoring Systems (SHMS-E), fabricated by Mid-Columbia Engineering (MCE) for installation on the Waste Tank Farms in the Hanford 200 Areas, are constructed as intended by the design. The ATP performance will verify proper system fabrication

  14. Optimization of the photovoltaic-hydrogen supply system of a stand-alone remote-telecom application

    Energy Technology Data Exchange (ETDEWEB)

    Gomez, Guillermo; Martinez, Graciano; Galvez, Jose L.; Cuevas, Raquel; Maellas, Jesus [National Institute for Aerospace Technology (INTA), Renewable Energy Department, Ctra. Ajalvir km 4, E-28850 Torrejon de Ardoz, Madrid (Spain); Gila, Raul; Bueno, Emilio [Polytechnical School - Alcala de Henares University, Electronics Department, Campus Universitario, Ctra. De Madrid-Barcelona Km 33.600, Alcala de Henares, Madrid (Spain)

    2009-07-15

    Hydrogen is considered as the optimal carrier for the surplus energy storage from renewable resources. Although hydrogen and its application in fuel cell is considered as a high-cost energy system, some cost-efficient solutions have been found for their use in stand-alone applications, which usually depend on the variability of renewable sources that have to be oversized in order to reduce their dependence on external energy sources. This paper shows the results from the simulation of several alternatives of introducing hydrogen technologies to increase the independence of a remote-telecom application fed by photovoltaic panels. Hydrogen is obtained by electrolysis and it is used in a fuel cell when the renewable energy source is not enough to maintain the stand-alone application. TRNSYS simulation environment has been used for evaluating the proposed alternatives. The results show that the best configuration option is that considering the use of hydrogen as a way to storage the surplus of radiation and the management system can vary the number of photovoltaic panels assigned to feed the hydrogen generation, the batteries or the telecom application. (author)

  15. Photoelectrochemical based direct conversion systems for hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Kocha, S.; Peterson, M.; Arent, D. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-10-01

    Photon driven, direct conversion systems consist of a light absorber and a water splitting catalyst as a monolithic system; water is split directly upon illumination. This one-step process eliminates the need to generate electricity externally and subsequently feed it to an electrolyzer. These configurations require only the piping necessary for transport of hydrogen to an external storage system or gas pipeline. This work is focused on multiphoton photoelectrochemical devices for production of hydrogen directly using sunlight and water. Two types of multijunction cells, one consisting of a-Si triple junctions and the other GaInP{sub 2}/GaAs homojunctions, were studied for the photoelectrochemical decomposition of water into hydrogen and oxygen from an aqueous electrolyte solution. To catalyze the water decomposition process, the illuminated surface of the device was modified either by addition of platinum colloids or by coating with ruthenium dioxide. These colloids have been characterized by gel electrophoresis.

  16. Single-cell-based system to monitor carrier driven cellular auxin homeostasis

    Science.gov (United States)

    2013-01-01

    Background Abundance and distribution of the plant hormone auxin play important roles in plant development. Besides other metabolic processes, various auxin carriers control the cellular level of active auxin and, hence, are major regulators of cellular auxin homeostasis. Despite the developmental importance of auxin transporters, a simple medium-to-high throughput approach to assess carrier activities is still missing. Here we show that carrier driven depletion of cellular auxin correlates with reduced nuclear auxin signaling in tobacco Bright Yellow-2 (BY-2) cell cultures. Results We developed an easy to use transient single-cell-based system to detect carrier activity. We use the relative changes in signaling output of the auxin responsive promoter element DR5 to indirectly visualize auxin carrier activity. The feasibility of the transient approach was demonstrated by pharmacological and genetic interference with auxin signaling and transport. As a proof of concept, we provide visual evidence that the prominent auxin transport proteins PIN-FORMED (PIN)2 and PIN5 regulate cellular auxin homeostasis at the plasma membrane and endoplasmic reticulum (ER), respectively. Our data suggest that PIN2 and PIN5 have different sensitivities to the auxin transport inhibitor 1-naphthylphthalamic acid (NPA). Also the putative PIN-LIKES (PILS) auxin carrier activity at the ER is insensitive to NPA in our system, indicating that NPA blocks intercellular, but not intracellular auxin transport. Conclusions This single-cell-based system is a useful tool by which the activity of putative auxin carriers, such as PINs, PILS and WALLS ARE THIN1 (WAT1), can be indirectly visualized in a medium-to-high throughput manner. Moreover, our single cell system might be useful to investigate also other hormonal signaling pathways, such as cytokinin. PMID:23379388

  17. Nanostructured lipid carrier system for topical delivery of terbinafine hydrochloride

    Directory of Open Access Journals (Sweden)

    Bharti Gaba

    2015-12-01

    Full Text Available The main aim of the present study was to develop and evaluate Terbinafine HCl (TH-loaded nanostructured lipid carrier (NLC for the treatment of fungal infection via topical administration. Fungal infections are tremendously widespread and the treatments are effective but associated toxicities restrict their use. TH-NLC was prepared using high pressure homogenization technique using Glyceryl Monostearate (GMS as solid lipid, Labrasol as liquid lipid and Pluronic F-127 as surfactant, binary lipid phase was selected in the ratio 6:4 w/w (solid:liquid lipid ratio. The mean diameter of optimized TH-NLCs was found to be 128 ± 4.5 nm. Spherical shape and size were confirmed using scanning electron microscopy (SEM and transmission electron microscopy (TEM analyses. The in vitro release studies showed 92.60 ± 0.87% drug release over 24 h as compared to the marketed formulation which showed only 82.826 ± 0.29%. Ex vivo skin permeation study showed about 86.35% permeation however from the marketed formulation it showed 69.41%. The pharmacodynamic studies indicated that TH-NLC (771 ± 41.797 CFUs gel efficiently reduced the fungal burden in shorter duration of time as compared to marketed formulation (1558 ± 140.524 CFUs and dispersion (95,582 ± 2316.619 CFUs (p value > 0.001. Therefore, it can be concluded that the developed NLCs showed a sustained release pattern and reduction of fungal burden in the infected area. Hence, TH-NLC could be a potential alternative for treatment of topical fungal infection after clinical evaluation in near future.

  18. Development of hydrogen storage systems using sodium alanate

    Energy Technology Data Exchange (ETDEWEB)

    Lozano Martinez, Gustavo Adolfo

    2010-12-06

    In this work, hydrogen storage systems based on sodium alanate were studied, modelled and optimised, using both experimental and theoretical approaches. The experimental approach covered investigations of the material from mg scale up to kg scale in demonstration test tanks, while the theoretical approach discussed modelling and simulation of the hydrogen sorption process in a hydride bed. Both approaches demonstrated the strong effect of heat transfer on the sorption behaviour of the hydride bed and led to feasible methods to improve and optimise the volumetric and gravimetric capacities of hydrogen storage systems. The applied approaches aimed at an optimal integration of sodium alanate material in practical hydrogen storage systems. First, it was experimentally shown that the size of the hydride bed influences the hydrogen sorption behaviour of the material. This is explained by the different temperature profiles that are developed inside the hydride bed during the sorptions. In addition, in a self-constructed cell it was possible to follow the hydrogen sorptions and the developed temperature profiles within the bed. Moreover, the effective thermal conductivity of the material was estimated in-situ in this cell, given very good agreement with reported values of ex-situ measurements. It was demonstrated that the effective thermal conductivity of the hydride bed can be enhanced by the addition of expanded graphite. This enhancement promotes lower temperature peaks during the sorptions due to faster heat conduction through the bed, which in addition allows faster heat transfer during sorption. Looking towards simulations and further evaluations, empirical kinetic models for both hydrogen absorption and desorption of doped sodium alanate were developed. Based on the results of the model, the optimal theoretical pressure-temperature conditions for hydrogen sorptions were determined. A new approach is proposed for the mass balance of the reactions when implementing

  19. Contribution to the study of the uranium-hydrogen system; Contribution a l'etude du systeme uranium-hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Chevallier, J [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-01-01

    Previous work on uranium-hydrogen system is reviewed. The U-H{sub 2}-UH{sub n} equilibrium is then investigated at pressures below one atmosphere, i.e. at temperatures lower than 430 deg. C. The hydride obtained at equilibrium is deficient in hydrogen (UH{sub n<3}), the hydrogen deficit increasing as the temperature rises. Thermodynamic functions for the formation of non-stoichiometric hydride and of one hydrogen vacancy are derived from pressure composition isotherms, in U-H phase diagram is proposed. The hydrogenation of U-UC alloys is also examined at pressures below one atmosphere with regard to the equilibrium: (free U + UC) - H{sub 2}-UH{sub n}. The equilibrium conditions are found different from that observed for pure uranium. (author) [French] Une etude bibliographique du systeme uranium-hydrogene est exposee. L'equilibre U-H{sub 2}-UH{sub n} est ensuite etudie sous des pressions inferieures a une atmosphere, soit aux temperatures inferieures a environ 430 degs. C. L'hydrure obtenu a l'equilibre est deficitaire en hydrogene - UH{sub n<3} - et d'autant plus que la temperature s'eleve. Les grandeurs thermodynamiques relatives a la formation et a la saturation de l'hydrure, ainsi qu'a la formation d'une lacune d'hydrogene sont deduites des pressions d'equilibre. Un modele de diagramme de phases U-H est propose. L'hyduration des alliages U-UC est etudiee egalement sous des pressions inferieures a l'atmosphere, au point de vue de l'equilibre (U libre + UC) - H{sub 2}-UH{sub n}. Les conditions d'equilibre sont trouvees differentes de celles observees sur l'uranium pur. (auteur)

  20. Alternative Energetics DC Microgrid With Hydrogen Energy Storage System

    Directory of Open Access Journals (Sweden)

    Zaļeskis Genadijs

    2016-12-01

    Full Text Available This paper is related to an alternative energetics microgrid with a wind generator and a hydrogen energy storage system. The main aim of this research is the development of solutions for effective use of the wind generators in alternative energetics devices, at the same time providing uninterrupted power supply of the critical loads. In this research, it was accepted that the alternative energetics microgrid operates in an autonomous mode and the connection to the conventional power grid is not used. In the case when wind speed is low, the necessary power is provided by the energy storage system, which includes a fuel cell and a tank with stored hydrogen. The theoretical analysis of the storage system operation is made. The possible usage time of the stored hydrogen depends on the available amount of hydrogen and the consumption of the hydrogen by the fuel cell. The consumption, in turn, depends on used fuel cell power. The experimental results suggest that if the wind generator can provide only a part of the needed power, the abiding power can be provided by the fuel cell. In this case, a load filter is necessary to decrease the fuel cell current pulsations.

  1. Phase equilibria in the niobium-vanadium-hydrogen system

    Energy Technology Data Exchange (ETDEWEB)

    Bethin, J. (Grumman Aerospace Corp., Bethpage, NY (USA)); Welch, D.O. (Brookhaven National Lab., Upton, NY (USA)); Pick, M.A. (Commission of the European Communities, Abingdon (UK). JET Joint Undertaking)

    1990-01-01

    The effect of vanadium additions to niobium on the metal-hydrogen phase equilibria has been studied. Measurements of the equilibrium H{sub 2}(D{sub 2}) pressure-composition-temperature isotherms for Nb{sub 1-x}V{sub x} alloys with 0{le}x<0.2 were used to determine the depression of the {alpha} - {alpha}' critical temperature with increasing vanadium concentration. A simple lattice-fluid model guided reduction of the data. Changes in the triple point temperature as well as the shift of the {zeta} {yields} {epsilon} phase transition were determined by differential scanning calorimetry measurements. A rapid overall depression was found, of the order of 7 K (at.% substituted V){sup -1}, for the metal-hydrogen (deuterium) phase boundary structure when compared with the Nb-H system in the hydrogen concentration range of interest. The results explain the enhanced terminal solubility of hydrogen in this system found previously by other authors. The changes in the phase equilibria are discussed in terms of the effect of hydrogen trapping and compared with the results of a cluster-variation calculation for random-field systems of previous authors, taking into account a distribution of H-site energies due to alloying. (author).

  2. Standard hydrogen monitoring system-B operation and maintenance manual

    International Nuclear Information System (INIS)

    Bender, R.M.

    1995-01-01

    The purpose of this document is to provide information for the operation and maintenance of the Standards Hydrogen Monitoring System-B (SHMS-B) used in the 200E and 200W area tank farms on the Hanford site. This provides information specific to the mechanical operation of the system and is not intended to take the place of a Plant Operating Procedure. The primary function of the SHMS-B is to monitor specifically for hydrogen in the waste tank vapor space which may also contain unknown quantities of other gaseous constituents

  3. Tritiated hydrogen gas storage systems for a fusion plant

    International Nuclear Information System (INIS)

    Bramy, W.; Hircq, B.; Peyrat, M.; Leger, D.

    1992-01-01

    This paper reports that USSI INGENIERIE has carried out a study financed by European Communities Commission concerning the NET/ITER project, on tritium Fuel Management and Storage systems of the International Thermonuclear Experimental Reactor. A processing block diagram for hydrogen isotopes represents all interfaces and possible links between these systems and tritiated gas mixtures flowing through the Fusion plant. Large quantities of hydrogen isotopes (up to several thousand moles of protium, deuterium and tritium) in gaseous form associated with torus fuelling and exhaust pellet injection, and neutral beam injection, must be stored and managed in such a plant

  4. Hydrogen can be used as a perfect fuel

    International Nuclear Information System (INIS)

    Aydin, E.

    2005-01-01

    At present, hydrogen is one of the new and clean energy production sources. Hydrogen is the perfect partner for electricity, and together they create an integrated energy system based on distributed power generation and use. Hydrogen and electricity are interchangeable using a fuel cell (to convert hydrogen to electricity) or an electrolyzer (for converting electricity to hydrogen). A regenerative fuel cell works either way, converting hydrogen to electricity and vice versa. Hydrogen and electricity are both energy carriers because, unlike naturally occurring hydrocarbon fuels, they must both be produced using a primary energy source. In this study, it will be discussed whether hydrogen is perfect fuel or not

  5. DGEMP/CGP energy policy lecture cycle - technical and economical stakes of hydrogen as an energy carrier

    International Nuclear Information System (INIS)

    Alleau, T.; Freund, E.; Coiffard, J.

    2002-01-01

    Hydrogen is attracting a lot a interest from energy specialists, in particular because supply safety issues are back on the agendas. One of the most promising applications seems to be the 'combustible cells', which changes hydrogen into electricity and heat in various applications: 'mobile', as an alternative to electric cells, for instance in telephones or lap-top computers, 'stationary' for producing electricity and heat, including small and medium voltage, and 'transport' with a high number of light vehicle and even bus prototypes. (authors)

  6. Direct coupling of a solar-hydrogen system in Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Arriaga, L.G. [Gerencia de Energias No Convencionales, Instituto de Investigaciones Electricas (IIE), Av. Reforma 113, Col. Palmira, 62490 Cuernavaca, Morelos (Mexico); Centro de Investigacion y Desarrollo Tecnologico en Electroquimica S.C., Parque tecnologico Queretaro Sanfandila, Pedro Escobedo, C.P. 76703 Queretaro (Mexico); Martinez, W. [Departamento de Materiales Solares, CIE-UNAM, Av. Xochicalco s/n, Col. Centro, 62580 Temixco, Morelos (Mexico); Cano, U.; Blud, H. [Gerencia de Energias No Convencionales, Instituto de Investigaciones Electricas (IIE), Av. Reforma 113, Col. Palmira, 62490 Cuernavaca, Morelos (Mexico)

    2007-09-15

    The scope of this article is to show the initial results obtained in the interconnection of a 2.7 kW solar panel system with a solid polymer electrolyte (SPE) electrolyzer. The Non-Conventional Energies Department (ENC) at the Electrical Research Institute (IIE) considers that the storage of this intermittent energy by a chemical element such as hydrogen can be advantageous for certain applications. One of the arguments is that unlike traditional battery systems, hydrogen presents the great advantage of not discharging its energy content as long as it is not used. The solar-hydrogen (S-H) system proposed consists of a commercial electrolyzer stack by Proton Energy Systems and a photovoltaic (PV) solar system of 36 panels (75 W each) of monocrystalline silicon (Siemens) interconnected in a configuration for 2.7 kW power at 48V{sub DC}. The complete electrolyzer (stack plus auxiliaries) has a maximum capacity of 1000lN/h of hydrogen with a power energy consumption of 8 kVA (220V{sub AC}, 32 A) and uses a stack of 25 cells of SPE with an energy consumption of 5.6 kW. We present voltage, current and energy consumption of the electrolyzer as a whole system and of the stack alone, as well as hydrogen quantification for the Hogen 40 operating in laboratory. These results allowed us to estimate the possibilities of coupling the electrolyzer stack alone, i.e. no auxiliaries nor power conditioning, with the solar PV system. Results such as I-E curves of the solar PV system obtained at different irradiances and temperatures, as well as I-E curve of SPE electrolyzer stack, gave direction for confirming that PV system configuration was sufficiently good to have the electrolyzer stack working near the maximum power point at a good range of irradiances ({proportional_to}600-800W/m{sup 2}). (author)

  7. 78 FR 72146 - Motor Carrier Management Information System (MCMIS) Changes to Improve Uniformity in the...

    Science.gov (United States)

    2013-12-02

    ...-0457] Motor Carrier Management Information System (MCMIS) Changes to Improve Uniformity in the... Management Information System (MCMIS) to allow the Agency to upload the results of associated adjudicated... information concerning a citation associated with a violation that was dismissed or resulted in a finding of...

  8. Downlink Performance of a Multi-Carrier MIMO System in a Bursty Traffic Cellular Network

    DEFF Research Database (Denmark)

    Nguyen, Hung Tuan; Kovacs, Istvan; Wang, Yuanye

    2011-01-01

    In this paper we analyse the downlink performance of a rank adaptive multiple input multiple output (MIMO) system in a busty traffic cellular network. A LTE-Advanced system with multiple component carriers was selected as a study case. To highlight the advantage of using MIMO techniques, we used ...

  9. A study of industrial hydrogen and syngas supply systems

    Science.gov (United States)

    Amos, W. J.; Solomon, J.; Eliezer, K. F.

    1979-01-01

    The potential and incentives required for supplying hydrogen and syngas feedstocks to the U.S. chemical industry from coal gasification systems were evaluated. Future hydrogen and syngas demand for chemical manufacture was estimated by geographic area and projected economics for hydrogen and syngas manufacture was estimated with geographic area of manufacture and plant size as parameters. Natural gas, oil and coal feedstocks were considered. Problem areas presently affecting the commercial feasibility of coal gasification discussed include the impact of potential process improvements, factors involved in financing coal gasification plants, regulatory barriers affecting coal gasification, coal mining/transportation, air quality regulations, and competitive feedstock pricing barriers. The potential for making coal gasification the least costly H2 and syngas supply option. Options to stimulate coal gasification system development are discussed.

  10. Effective information rates of single-carrier and multi-carrier modulation schemes for bandwidth constrained IM/DD systems

    KAUST Repository

    Mazahir, Sana

    2017-07-31

    Information-theoretic and signal processing aspects of some modulation schemes designed for intensity modulation/direct detection (IM/DD) optical wireless communication (OWC) systems are studied. Due to the constraints of IM/DD signals (non-negative real and baseband signals), the construction of these signals along with their time and frequency characteristics differ from their RF counterparts. This necessitates a careful study of such schemes under practical constraints. Three schemes are studied in this paper, namely, single carrier pulse amplitude modulation (SC-PAM), asymmetrically clipped optical OFDM (ACO-OFDM), and DC biased optical OFDM (DCO-OFDM). Our aim is to carry out a comparative study of these schemes in the presence of identical constraints on bandwidth and average optical power. The study reveals that the clipping operation required in ACO-OFDM significantly reduces its information rate, and as a result, it is outperformed by SC-PAM. Such a limitation does not apply to DCO-OFDM which has a higher information rate, even though part of the available optical power is expended in the non-information-bearing DC bias.

  11. Emission scenarios for a global hydrogen economy and the consequences for global air pollution

    NARCIS (Netherlands)

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

    2011-01-01

    Hydrogen is named as possible energy carrier for future energy systems. However, the impact of large-scale hydrogen use on the atmosphere is uncertain. Application of hydrogen in clean fuel cells reduces emissions of air pollutants, but emissions from hydrogen production and leakages of molecular

  12. Hydrogen energy

    International Nuclear Information System (INIS)

    2005-03-01

    This book consists of seven chapters, which deals with hydrogen energy with discover and using of hydrogen, Korean plan for hydrogen economy and background, manufacturing technique on hydrogen like classification and hydrogen manufacture by water splitting, hydrogen storage technique with need and method, hydrogen using technique like fuel cell, hydrogen engine, international trend on involving hydrogen economy, technical current for infrastructure such as hydrogen station and price, regulation, standard, prospect and education for hydrogen safety and system. It has an appendix on related organization with hydrogen and fuel cell.

  13. 47 CFR 15.113 - Power line carrier systems.

    Science.gov (United States)

    2010-10-01

    ....113 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL RADIO FREQUENCY DEVICES Unintentional... shall submit the details of all existing systems plus any proposed new systems or changes to existing... operation on electric lines which connect the distribution substation to the customer or house wiring. Such...

  14. Physicochemical characterisation and investigation of the bonding mechanisms of API-titanate nanotube composites as new drug carrier systems.

    Science.gov (United States)

    Sipos, Barbara; Pintye-Hódi, Klára; Kónya, Zoltán; Kelemen, András; Regdon, Géza; Sovány, Tamás

    2017-02-25

    Titanate nanotube (TNT) has recently been explored as a new carrier material for active pharmaceutical ingredients (API). The aim of the present work was to reveal the physicochemical properties of API-TNT composites, focusing on the interactions between the TNTs and the incorporated APIs. Drugs belonging to different Biopharmaceutical Classification System (BCS) classes were loaded into TNTs: diltiazem hydrochloride (BCS I.), diclofenac sodium (BCS II.), atenolol (BCS III.) and hydrochlorothiazide (BCS IV.). Experimental results demonstrated that it is feasible for spiral cross-sectioned titanate nanotubes to carry drugs and maintain their bioactivity. The structural properties of the composites were characterized by a range of analytical techniques, including FT-IR, DSC, TG-MS, etc. The interactions between APIs and TNTs were identified as electrostatic attractions, mainly dominated by hydrogen bonds. Based on the results, it can be stated that the strength of the association depends on the hydrogen donor strength of the API. The drug release of incorporated APIs was evaluated from compressed tablets and compared to that of pure APIs. Differences noticed in the dissolution profiles due to incorporation showed a correlation with the strength of interactions between the APIs and the TNTs observed in the above analytical studies. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Immune cells: more than simple carriers for systemic delivery of oncolytic viruses

    Directory of Open Access Journals (Sweden)

    Eisenstein S

    2014-11-01

    Full Text Available Samuel Eisenstein,1 Shu-Hsia Chen,2 Ping-Ying Pan21Department of Surgery, 2Department of Oncological Sciences and Tisch Cancer Institute, The Icahn School of Medicine at Mount Sinai, New York, NY, USAAbstract: Oncolytic virotherapy on its own has numerous drawbacks, including an inability of the virus to actively target tumor cells and systemic toxicities at the high doses necessary to effectively treat tumors. Addition of immune cell-based carriers of oncolytic viruses holds promise as a technique in which oncolytic virus can be delivered directly to tumors in smaller and less toxic doses. Interestingly, the cell carriers themselves have also demonstrated antitumor effects, which can be augmented further by tailoring the appropriate oncolytic virus to the appropriate cell type. This review discusses the multiple factors that go into devising an effective, cell-based delivery system for oncolytic viruses.Keywords: oncolytic virus, cell carrier, immune cells, cancer therapy, myeloid-derived suppressor cells

  16. Quantum-Classical Connection for Hydrogen Atom-Like Systems

    Science.gov (United States)

    Syam, Debapriyo; Roy, Arup

    2011-01-01

    The Bohr-Sommerfeld quantum theory specifies the rules of quantization for circular and elliptical orbits for a one-electron hydrogen atom-like system. This article illustrates how a formula connecting the principal quantum number "n" and the length of the major axis of an elliptical orbit may be arrived at starting from the quantum…

  17. Storing in carbon nano structures for hybrid systems solar hydrogen

    International Nuclear Information System (INIS)

    Marazzi, R.; Zini, G.; Tartarini, P.

    2009-01-01

    We have developed a hybrid energy system for converting energy from renewable sources and its storage in the form of hydrogen. The storage uses activated carbon and the methodology was modelled mathematically and simulated in numerical software. The results show that storage compression is cheaper storage for liquefaction. [it

  18. High purity hydrogen production system by the PSA method

    Energy Technology Data Exchange (ETDEWEB)

    1986-01-01

    In a process developed by Nippon Steel, coke oven gas is compressed and purified of tarry matter, sulphur compounds and gum-formers by adsorption. It is then passed through a three-tower pressure-swing adsorption system to recover hydrogen whose purity can be selected in the range 99 to 99.999%. A composite adsorption agent is used.

  19. Microcomputer-aided monitor for liquid hydrogen target system

    International Nuclear Information System (INIS)

    Kitami, T.; Watanabe, K.

    1983-03-01

    A microcomputer-aided monitor for a liquid hydrogen target system has been designed and tested. Various kinds of input data such as temperature, pressure, vacuum, etc. are scanned in a given time interval. Variation with time in any four items can be displayed on CRT and, if neccessary, printed out on a sheet of recording paper. (author)

  20. Dynamic Simulation and Optimization of Nuclear Hydrogen Production Systems

    Energy Technology Data Exchange (ETDEWEB)

    Paul I. Barton; Mujid S. Kaximi; Georgios Bollas; Patricio Ramirez Munoz

    2009-07-31

    This project is part of a research effort to design a hydrogen plant and its interface with a nuclear reactor. This project developed a dynamic modeling, simulation and optimization environment for nuclear hydrogen production systems. A hybrid discrete/continuous model captures both the continuous dynamics of the nuclear plant, the hydrogen plant, and their interface, along with discrete events such as major upsets. This hybrid model makes us of accurate thermodynamic sub-models for the description of phase and reaction equilibria in the thermochemical reactor. Use of the detailed thermodynamic models will allow researchers to examine the process in detail and have confidence in the accurary of the property package they use.

  1. 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.

  2. The 4-particle hydrogen-anti-hydrogen system revisited. Twofold molecular Hamiltonian symmetry and natural atom anti-hydrogen

    International Nuclear Information System (INIS)

    Van Hooydonk, G.

    2005-01-01

    The historical importance of the original quantum mechanical bond theory proposed by Heitler and London in 1927 as well as its pitfalls are reviewed. Modern ab initio treatments of H-H-bar systems are inconsistent with the logic behind algebraic Hamiltonians H ± = H 0 ± ΔH for charge-symmetrical and charge-asymmetrical 4 unit charge systems like H 2 and HH-bar. Their eigenvalues are exactly those of 1927 Heitler-London (HL) theory. Since these 2 Hamiltonians are mutually exclusive, only the attractive one can apply for stable natural molecular H 2 . A wrong choice leads to problems with anti-atom H-bar. In line with earlier results on band and line spectra, we now prove that HL chose the wrong Hamiltonian for H 2 . Their theory explains the stability of attractive system H 2 with a repulsive Hamiltonian H 0 + ΔH instead of with the attractive one H 0 - ΔH, representative for charge-asymmetrical system HH-bar. A new second order symmetry effect is detected in this attractive Hamiltonian, which leads to a 3-dimensional structure for the 4-particle system. Repulsive HL Hamiltonian H + applies at long range but at the critical distance, attractive charge-inverted Hamiltonian H - takes over and leads to bond H 2 but in reality, HH-bar, for which we give an analytical proof. This analysis confirms and generalizes an earlier critique of the wrong long range behavior of HL-theory by Bingel, Preuss and Schmidtke and by Herring. Another wrong asymptote choice in the past also applies for atomic anti-hydrogen H-bar, which has hidden the Mexican hat potential for natural hydrogen. This generic solution removes most problems, physicists and chemists experience with atomic H-bar and molecular HH-bar, including the problem with antimatter in the Universe. (author)

  3. Helium-Hydrogen Recovery System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Immense quantities of expensive liquefied helium are required at Stennis and Kennedy Space Centers for pre-cooling rocket engine propellant systems prior to filling...

  4. Photocatalytic hydrogen generation enhanced by band gap narrowing and improved charge carrier mobility in AgTaO3 by compensated co-doping.

    Science.gov (United States)

    Li, Min; Zhang, Junying; Dang, Wenqiang; Cushing, Scott K; Guo, Dong; Wu, Nianqiang; Yin, Penggang

    2013-10-14

    The correlation of the electronic band structure with the photocatalytic activity of AgTaO3 has been studied by simulation and experiments. Doping wide band gap oxide semiconductors usually introduces discrete mid-gap states, which extends the light absorption but has limited benefit for photocatalytic activity. Density functional theory (DFT) calculations show that compensated co-doping in AgTaO3 can overcome this problem by increasing the light absorption and simultaneously improving the charge carrier mobility. N/H and N/F co-doping can delocalize the discrete mid-gap states created by sole N doping in AgTaO3, which increases the band curvature and the electron-to-hole effective mass ratio. In particular, N/F co-doping creates a continuum of states that extend the valence band of AgTaO3. N/F co-doping thus improves the light absorption without creating the mid-gap states, maintaining the necessary redox potentials for water splitting and preventing from charge carrier trapping. The experimental results have confirmed that the N/F-codoped AgTaO3 exhibits a red-shift of the absorption edge in comparison with the undoped AgTaO3, leading to remarkable enhancement of photocatalytic activity toward hydrogen generation from water.

  5. Standard Hydrogen Monitoring System-C operation and maintenance manual

    International Nuclear Information System (INIS)

    Schneider, T.C.

    1997-01-01

    The primary function of the SHMS-C is to monitor specifically for hydrogen in the waste tank vapor space which may also contain (but not be limited to) unknown quantities of air, nitrous oxide (N 2 O), ammonia (NH 3 ), water vapor, carbon dioxide (CO 2 ), carbon monoxide (CO) and other gaseous constituents. An electronically controlled grab sampler has replaced the manually operated sample system that was used in the original SHMS enclosure. Samples can now be operator or automatically initiated. Automatic initiation occurs based on the high hydrogen alarm level. Once a sample is obtained it is removed from the sampler and transported to a laboratory for analysis. This system is used to identify other gaseous constituents which are not measured by the hydrogen monitor. The design does not include any remote data acquisition or remote data logging equipment but provides a 4--20 mA dc process signals, and discrete alarm contacts, that can be utilized for remote data logging and alarming when desired. The SHMS-C arrangement consists of design modifications (piping, valves, filters, supports) to the SHMS-B arrangement necessary for the installation of a dual column gas chromatograph and associated sample and calibration gas lines. The gas chromatograph will provide real time, analytical quality, specific hydrogen measurements in low and medium range concentrations. The system is designed to sample process gases that are classified by NEC code as Class 1, Division 1, Group B

  6. Tungsten-188/carrier-free rhenium-188 perrhenic acid generator system

    International Nuclear Information System (INIS)

    Knapp, F.F. Jr.; Lisic, E.C.; Mirzadeh, S.; Callahan, A.P.

    1993-01-01

    A generator system for providing a carrier-free radioisotope in the form of an acid comprises a chromatography column in tandem fluid connection with an ion exchange column, the chromatography column containing a charge of a radioactive parent isotope. The chromatography column, charged with a parent isotope, is eluted with an alkali metal salt solution to generate the radioisotope in the form of an intermediate solution, which is passed through the ion-exchange column to convert the radioisotope to a carrier-free acid form

  7. Development of a stealth carrier system for structural studies of membrane proteins in solution

    DEFF Research Database (Denmark)

    Maric, Selma

    Structural studies of membrane proteins remain a great experimental challenge. Functional reconstitution into artificial carriers that mimic the native bilayer environment allows for the handling of membrane proteins in solution and enables the use of small-angle scattering techniques for fast...... and reliable structural analysis. The difficulty with this approach is that the carrier discs contribute to the measured scattering intensity in a highly non-trivial fashion, making subsequent data analysis challenging. This thesis presents the development of a specifically deuterated, stealth nanodisc system...

  8. Carrier phase synchronization system for improved amplitude modulation and television broadcast reception

    Science.gov (United States)

    Smith, Stephen F [Loudon, TN; Moore, James A [Powell, TN

    2009-09-08

    Systems and methods are described for carrier phase synchronization for improved AM and TV broadcast reception. A method includes synchronizing the phase of a carrier frequency of a broadcast signal with the phase of a remote reference frequency. An apparatus includes a receiver to detect the phase of a reference signal; a phase comparator coupled to the reference signal-phase receiver; a voltage controlled oscillator coupled to the phase comparator; and a phase-controlled radio frequency output coupled to the voltage controlled oscillator.

  9. Charge transport in disordered organic host-guest systems: effects of carrier density and electric field

    NARCIS (Netherlands)

    Yimer, Y.Y.; Bobbert, P.A.; Coehoorn, R.

    2008-01-01

    We investigate charge transport in disordered organic host–guest systems with a bimodal Gaussian density of states (DOS). The energy difference between the two Gaussians defines the trap depth. By solving the Pauli master equation for the hopping of charge carriers on a regular lattice with site

  10. Charge transport in disordered organic host-guest systems: effects of carrier density and electric field

    NARCIS (Netherlands)

    Yimer, Y.Y.; Bobbert, P.A.; Coehoorn, R.

    2009-01-01

    We investigate charge transport in disordered organic host–guest systems with a bimodal Gaussian density of states. The energy difference between the peaks of the two Gaussians defines the trap depth. By solving the Pauli master equation for the hopping of charge carriers on a regular lattice we

  11. Proposed configuration for ITER hydrogen isotope separation system (ISS)

    International Nuclear Information System (INIS)

    Lazar, A.; Brad, S.; Sofalca, N.; Vijulie, M.; Cristescu, I.; Doer, L; Wurster, W.

    2008-01-01

    Full text: The isotope separation system utilizes cryogenic distillation and catalytic reaction for isotope exchange to separate elemental hydrogen isotope gas mixtures. The ISS shall separate hydrogen isotope mixtures from two sources to produce up to five different products. These are: protium, effluent for discharge to the atmosphere, deuterium for fuelling, deuterium for NB injector (NBI) source gas, 50 % and 90% T fuelling streams. The concept of equipment 3D layout for the ISS main components were developed using the Part Design, Assembly Design, Piping Design, Equipment Arrangement and Plant Layout application from CATIA V5. The 3D conceptual layouts for ISS system were created having as reference the DDD -32-B report, the drawings 0028.0001.2D. 0100. R 'Process Flow Diagram'; 0029.0001.2D. 0200.R 'Process Instrumentation Diagram -1' (in the cold box); 0030.0001.2D. 0100. R 'Process Instrumentation Diagram -2' (in the hard shell confinement) and imputes from TLK team. The main components designed for ISS are: ISS cold box system (CB) with cryogenic distillation columns (CD) and recovery heat exchangers (HX), ISS hard shell containment (HSC) system with metals bellow pumps (MB) and chemical equilibrators (RC), valve box system, instrumentation box system, vacuum system and hydrogen expansion vessels. Work related to these topics belongs to the contract FU06-CT-2006-00508 (EFDA 06-1511) from the EFDA Technology Workprogramm 2006 and was done in collaboration with FZK Association team during the period January 2007 - September 2008. (authors)

  12. Low molecular mass chitosan as carrier for hydrodynamically balanced system for sustained delivery of ciprofloxacin hydrochloride

    OpenAIRE

    VERMA, ANURAG; BANSAL, ASHOK K.; GHOSH, AMITAVA; PANDIT, JAYANTA K.

    2012-01-01

    Chitosan has become a focus of major interest in recent years due to its excellent biocompatibility, biodegradability and non-toxicity. Although this material has already been extensively investigated in the design of different types of drug delivery systems, it is still little explored for stomach specific drug delivery systems. The objective of the present investigation was to explore the potential of low molecular mass chitosan (LMCH) as carrier for a hydrodynamically balanced system (HBS)...

  13. Updates on smart polymeric carrier systems for protein delivery.

    Science.gov (United States)

    El-Sherbiny, Ibrahim; Khalil, Islam; Ali, Isra; Yacoub, Magdi

    2017-10-01

    Smart materials are those materials that are responsive to chemical (organic molecules, chemical agents or specific agents), biochemical (protein, enzymes, growth factors, substrates or ligands), physical (electric field, magnetic field, temperature, pH, ionic strength or radiation) or mechanical (pressure or mechanical stress) signals. These responsive materials interact with the stimuli by changing their properties or conformational structures in a predictable manner. Recently, smart polymers have been utilized in various biomedical applications. Particularly, they have been used as a platform to synthesize stimuli-responsive systems that could deliver therapeutics to a specific site for a specific period with minimal adverse effects. For instance, stimuli-responsive polymers-based systems have been recently reported to deliver different bioactive molecules such as carbohydrates (heparin), chemotherapeutic agents (doxorubicin), small organic molecules (anti-coagulants), nucleic acids (siRNA), and proteins (growth factors and hormones). Protein therapeutics played a fundamental role in treatment of various chronic and some autoimmune diseases. For instance insulin has been used in treatment of diabetes. However, being a protein in nature, insulin delivery is limited by its instability, short half-life, and easy denaturation when administered orally. To overcome these challenges, and as highlighted in this review article, much research efforts have been recently devoted to design and develop convenient smart controlled nanosystems for protein therapeutics delivery.

  14. Metal-hydrogen systems with an exceptionally large and tunable thermodynamic destabilization

    NARCIS (Netherlands)

    Ngene, Peter; Longo, Alessandro; Mooij, L.P.A.; Bras, Wim; Dam, B.

    2017-01-01

    Hydrogen is a key element in the energy transition. Hydrogen-metal systems have been studied for various energy-related applications, e.g., for their use in reversible hydrogen storage, catalysis, hydrogen sensing, and rechargeable batteries. These applications depend strongly on the

  15. Towards sustainable energy systems: The related role of hydrogen

    International Nuclear Information System (INIS)

    Hennicke, Peter; Fischedick, Manfred

    2006-01-01

    The role of hydrogen in long run sustainable energy scenarios for the world and for the case of Germany is analysed, based on key criteria for sustainable energy systems. The possible range of hydrogen within long-term energy scenarios is broad and uncertain depending on assumptions on used primary energy, technology mix, rate of energy efficiency increase and costs degression ('learning effects'). In any case, sustainable energy strategies must give energy efficiency highest priority combined with an accelerated market introduction of renewables ('integrated strategy'). Under these conditions hydrogen will play a major role not before 2030 using natural gas as a bridge to renewable hydrogen. Against the background of an ambitious CO 2 -reduction goal which is under discussion in Germany the potentials for efficiency increase, the necessary structural change of the power plant system (corresponding to the decision to phase out nuclear energy, the transformation of the transportation sector and the market implementation order of renewable energies ('following efficiency guidelines first for electricity generation purposes, than for heat generation and than for the transportation sector')) are analysed based on latest sustainable energy scenarios

  16. Design of a photovoltaic-hydrogen-fuel cell energy system

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, P A; Chamberlin, C E [Humboldt State Univ., Arcata, CA (US). Dept. of Environmental Resources Engineering

    1991-01-01

    The design of a stand-alone renewable energy system using hydrogen (H{sub 2}) as the energy storage medium and a fuel cell as the regeneration technology is reported. The system being installed at the Humboldt State University Telonicher Marine Laboratory consists of a 9.2 kW photovoltaic (PV) array coupled to a high pressure, bipolar alkaline electrolyser. The array powers the Laboratory's air compressor system whenever possible; excess power is shunted to the electrolyser for hydrogen and oxygen (O{sub 2}) production. When the array cannot provide sufficient power, stored hydrogen and oxygen are furnished to a proton exchange membrane fuel cell which, smoothly and without interruption, supplies the load. In reporting the design, details of component selection, sizing, and integration, control system logic and implementation, and safety considerations are discussed. Plans for a monitoring network to chronicle system performance are presented, questions that will be addressed through the monitoring program are included, and the present status of the project is reported. (Author).

  17. Nuclear processes in deuterium/natural hydrogen-metal systems

    International Nuclear Information System (INIS)

    Zelensky, V.F.

    2013-01-01

    The survey presents the analysis of the phenomena taking place in deuterium - metal and natural hydrogen - metal systems under cold fusion experimental conditions. The cold fusion experiments have shown that the generation of heat and helium in the deuterium-metal system without emission of energetic gamma-quanta is the result of occurrence of a chain of chemical, physical and nuclear processes observed in the system, culminating in both the fusion of deuterium nuclei and the formation of a virtual, electron-modified excited 4He nucleus. The excitation energy of the helium nucleus is transferred to the matrix through emission of conversion electrons, and that, under appropriate conditions, provides a persistent synthesis of deuterium. The processes occurring in the deuterium/natural hydrogen - metal systems have come to be known as chemonuclear DD- and HD-fusion. The mechanism of stimulation of weak interaction reactions under chemonuclear deuterium fusion conditions by means of strong interaction reactions has been proposed. The results of numerous experiments discussed in the survey bear witness to the validity of chemonuclear fusion. From the facts discussed it is concluded that the chemonuclear deuterium fusion scenario as presented in this paper may serve as a basis for expansion of deeper research and development of this ecologically clean energy source. It is shown that the natural hydrogen-based system, containing 0.015% of deuterium, also has good prospects as an energy source. The chemonuclear fusion processes do not require going beyond the scope of traditional physics for their explanation

  18. Simultaneous Hydrogen Generation and Waste Acid Neutralization in a Reverse Electrodialysis System

    KAUST Repository

    Hatzell, Marta C.; Zhu, Xiuping; Logan, Bruce E.

    2014-01-01

    power and hydrogen gas using waste heat-derived solutions, but high electrode overpotentials limit system performance. We show here that an ammonium bicarbonate (AmB) RED system can achieve simultaneous waste acid neutralization and in situ hydrogen

  19. From Composition to Cure: A Systems Engineering Approach to Anticancer Drug Carriers.

    Science.gov (United States)

    MacEwan, Sarah R; Chilkoti, Ashutosh

    2017-06-06

    The molecular complexity and heterogeneity of cancer has led to a persistent, and as yet unsolved, challenge to develop cures for this disease. The pharmaceutical industry focuses the bulk of its efforts on the development of new drugs, but an alternative approach is to improve the delivery of existing drugs with drug carriers that can manipulate when, where, and how a drug exerts its therapeutic effect. For the treatment of solid tumors, systemically delivered drug carriers face significant challenges that are imposed by the pathophysiological barriers that lie between their site of administration and their site of therapeutic action in the tumor. Furthermore, drug carriers face additional challenges in their translation from preclinical validation to clinical approval and adoption. Addressing this diverse network of challenges requires a systems engineering approach for the rational design of optimized carriers that have a realistic prospect for translation from the laboratory to the patient. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Direct hydrogen fuel cell systems for hybrid vehicles

    Science.gov (United States)

    Ahluwalia, Rajesh K.; Wang, X.

    Hybridizing a fuel cell system with an energy storage system offers an opportunity to improve the fuel economy of the vehicle through regenerative braking and possibly to increase the specific power and decrease the cost of the combined energy conversion and storage systems. Even in a hybrid configuration it is advantageous to operate the fuel cell system in a load-following mode and use the power from the energy storage system when the fuel cell alone cannot meet the power demand. This paper discusses an approach for designing load-following fuel cell systems for hybrid vehicles and illustrates it by applying it to pressurized, direct hydrogen, polymer-electrolyte fuel cell (PEFC) systems for a mid-size family sedan. The vehicle level requirements relative to traction power, response time, start-up time and energy conversion efficiency are used to select the important parameters for the PEFC stack, air management system, heat rejection system and the water management system.

  1. The atomic hydrogen cloud in the saturnian system

    Science.gov (United States)

    Tseng, W.-L.; Johnson, R. E.; Ip, W.-H.

    2013-09-01

    The importance of Titan's H torus shaped by solar radiation pressure and of hydrogen atoms flowing out of Saturn's atmosphere in forming the broad hydrogen cloud in Saturn's magnetosphere is still debated. Since the Saturnian system also contains a water product torus which originates from the Enceladus plumes, the icy ring particles, and the inner icy satellites, as well as Titan's H2 torus, we have carried out a global investigation of the atomic hydrogen cloud taking into account all sources. We show that the velocity and angle distributions of the hot H ejected from Saturn's atmosphere following electron-impact dissociation of H2 are modified by collisions with the ambient atmospheric H2 and H. This in turn affects the morphology of the escaping hydrogen from Saturn, as does the morphology of the ionospheric electron distribution. Although an exact agreement with the Cassini observations is not obtained, our simulations show that H directly escaping from Titan is the dominant contributor in the outer magnetosphere. Of the total number of H observed by Cassini from 1 to 5RS, ∼5.7×1034, our simulations suggest ∼20% is from dissociation in the Enceladus torus, ∼5-10% is from dissociation of H2 in the atmosphere of the main rings, and ∼50% is from Titan's H torus, implying that ∼20% comes from Saturn atmosphere.

  2. The Laboratory for Laser Energetics’ Hydrogen Isotope Separation System

    Energy Technology Data Exchange (ETDEWEB)

    Shmayda, W.T., E-mail: wshm@lle.rochester.edu; Wittman, M.D.; Earley, R.F.; Reid, J.L.; Redden, N.P.

    2016-11-01

    The University of Rochester’s Laboratory for Laser Energetics has commissioned a hydrogen Isotope Separation System (ISS). The ISS uses two columns—palladium on kieselguhr and molecular sieve—that act in a complementary manner to separate the hydrogen species by mass. The 4-sL per day throughput system is compact and has no moving parts. The columns and the attendant gas storage and handling subsystems are housed in a 0.8 -m{sup 3} glovebox. The glovebox uses a helium cover gas that is continuously processed to extract oxygen and water vapor that permeates through the glovebox gloves and any tritium that is released while attaching or detaching vessels to add feedstock to or drawing product from the system. The isotopic separation process is automated and does not require manual intervention. A total of 315 TBq of tritium was extracted from 23.6 sL of hydrogen with tritium purities reaching 99.5%. Deuterium was the sole residual component in the processed gas. Raffinate contained 0.2 TBq of activity was captured for reprocessing. The total emission from the system to the environment was 0.4 GBq over three weeks.

  3. Socio-cultural barriers to the development of a sustainable energy system - the case of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Kjerulf Petersen, L.; Holst Andersen, A.

    2009-02-15

    Any transition to a more sustainable energy system, radically reducing greenhouse gas emissions, is bound to run in to a host of different barriers - technological and economic, but also socio-cultural. This will also be the case for any large-scale application of hydrogen as energy carrier, especially if the system is going to be based on renewable energy sources. The aim of these research notes is to review and discuss major socio-cultural barriers to new forms of energy supply in general and to hydrogen specifically. Reaching sufficient reductions in greenhouse gas emissions may require more than large-scale dissemination of renewable energy sources. Also reductions or moderations in energy demand may be necessary. Hence, a central point in the research note is to consider not only socio-cultural obstacles for changing technologies in energy production, distribution and consumption but also obstacles for changing the scale of energy consumption, i.e. moderating the growth in how much energy is consumed or even reducing consumption volumes. (au)

  4. A novel biological hydrogen production system. Impact of organic loading

    Energy Technology Data Exchange (ETDEWEB)

    Hafez, Hisham; Nakhla, George; El Naggar, Hesham [Western Ontario Univ. (Canada)

    2010-07-01

    The patent-pending system comprises a novel biohydrogen reactor with a gravity settler for decoupling of SRT from HRT. Two biohydrogenators were operated for 220 days at 37 C, hydraulic retention time 8 h and solids retention time ranged from 1.4 to 2 days under four different glucose concentrations of 2, 8, 16, 32, 48 and 64 g/L, corresponding to organic loading rates of 6.5-206 kg COD/m{sup 3}-d, and started up using anaerobically-digested sludge from the St. Marys wastewater treatment plant (St.Mary, Ontario, Canada) as the seed. The system steadily produced hydrogen with no methane. A maximum hydrogen yield of 3.1 mol H{sub 2} /mol glucose was achieved in the system for all the organic loading rates with an average of 2.8mol H{sub 2} /mol glucose. Acetate and butyrate were the main effluent liquid products at concentrations ranging from 640-7400 mg/L and 400-4600 mg/l, respectively, with no lactate detection. Microbial community analysis using denaturing gradient gel electrophoresis (DGGE) confirmed the absence of lactate producing bacteria Lactobacillus fermentum and other non-hydrogen producing species, and the predominance of various Clostridium species. Biomass concentrations in the biohydrogenators were steady, during the runs, varying form 1500 mg/L at the OLR of 6.5 kg COD/m{sup 3}-d to 14000 mg/L at the 104 kg COD/m{sup 3}-d, thus emphasizing the potential of this novel system for sustained stable hydrogen production and prevention of biomass washout. (orig.)

  5. Hydrogen-Oxygen PEM Regenerative Fuel Cell Energy Storage System

    Science.gov (United States)

    Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christopher P.

    2005-01-01

    An introduction to the closed cycle hydrogen-oxygen polymer electrolyte membrane (PEM) regenerative fuel cell (RFC), recently constructed at NASA Glenn Research Center, is presented. Illustrated with explanatory graphics and figures, this report outlines the engineering motivations for the RFC as a solar energy storage device, the system requirements, layout and hardware detail of the RFC unit at NASA Glenn, the construction history, and test experience accumulated to date with this unit.

  6. Evaluation tool for selection and optimisation of hydrogen demonstration projects. Application to a decentralized renewable hydrogen system

    International Nuclear Information System (INIS)

    Bracht, M.; De Groot, A.; Gregoire Padro, C.E.; Schucan, T.H.; Skolnik, E.

    1998-06-01

    As part of the International Energy Agency Hydrogen Implementing Agreement, an evaluation tool to assist in the design, operation and optimisation of hydrogen demonstration facilities is under development. Using commercially available flowsheet simulation software (ASPEN- Plus) as the integrating platform, this tool is designed to provide system developers with a comprehensive data base or library of component models and an integrating platform through which these models may be linked. By combining several energy system components a conceptual design of a integrated hydrogen energy system can be made. As a part of the tool and connected to the library are design guidelines which can help finding the optimal configuration in the design process. The component categories considered include: production, storage, transport, distribution and end use. Many component models have already been included in the initial test platform. The use of the tool will be illustrated by presenting the results of a specific sample system that has been designed and assessed with use of the tool. The system considered is a decentralized renewable hydrogen system in which the hydrogen is produced by biomass gasification or pyrolysis, the produced hydrogen is transported through a pipeline or with a tank truck. The storage options that are considered are liquid hydrogen and compressed gas. The hydrogen is dispensed through a refueling station. Several options for integration are conceivable; i.e. storage of the hydrogen can take place centrally or district heat of a gasification unit can be used to generate electricity for liquefaction, etc. With use of the tool several configurations with different components and various integration options have been examined. Both the results of the modeling effort and an assessment of the evaluation tool will be presented. 5 refs

  7. Hydrogen and renewable energy sources integrated system for greenhouse heating

    Directory of Open Access Journals (Sweden)

    Ileana Blanco

    2013-09-01

    Full Text Available A research is under development at the Department of Agro- Environmental Sciences of the University of Bari “Aldo Moro” in order to investigate the suitable solutions of a power system based on solar energy (photovoltaic and hydrogen, integrated with a geothermal heat pump for powering a self sustained heated greenhouse. The electrical energy for heat pump operation is provided by a purpose-built array of solar photovoltaic modules, which supplies also a water electrolyser system controlled by embedded pc; the generated dry hydrogen gas is conserved in suitable pressured storage tank. The hydrogen is used to produce electricity in a fuel cell in order to meet the above mentioned heat pump power demand when the photovoltaic system is inactive during winter night-time or the solar radiation level is insufficient to meet the electrical demand. The present work reports some theoretical and observed data about the electrolyzer operation. Indeed the electrolyzer has required particular attention because during the experimental tests it did not show a stable operation and it was registered a performance not properly consistent with the predicted performance by means of the theoretical study.

  8. Protein encapsulated magnetic carriers for micro/nanoscale drug delivery systems.

    Energy Technology Data Exchange (ETDEWEB)

    Xie, Y.; Kaminski, M. D.; Mertz, C. J.; Finck, M. R.; Guy, S. G.; Chen, H.; Rosengart, A. J.; Chemical Engineering; Univ. of Chicago, Pritzker School of Medicine

    2005-01-01

    Novel methods for drug delivery may be based on nanotechnology using non-invasive magnetic guidance of drug loaded magnetic carriers to the targeted site and thereafter released by external ultrasound energy. The key building block of this system is to successfully synthesize biodegradable, magnetic drug carriers. Magnetic carriers using poly(D,L-lactide-co-glycolide) (PLGA) or poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) as matrix materials were loaded with bovine serum albumin (BSA) by a double-emulsion technique. BSA-loaded magnetic microspheres were characterized for size, morphology, surface charge, and magnetization. The BSA encapsulation efficiency was determined by recovering albumin from the microspheres using dimethyl sulfoxide and 0.05N NaOH/0.5% SDS then quantifying with the Micro-BCA protein assay. BSA release profiles were also determined by the Micro-BCA protein assay. The microspheres had drug encapsulation efficiencies up to 90% depending on synthesis parameters. Particles were spherical with a smooth or porous surface having a size range less than 5 {mu}m. The surface charge (expressed as zeta potential) was near neutral, optimal for prolonged intravascular survival. The magnetization of these BSA loaded magnetic carriers was 2 to 6 emu/g, depending on the specific magnetic materials used during synthesis.

  9. Integrated energy systems for hydrogen and electricity supply

    Energy Technology Data Exchange (ETDEWEB)

    Muradov, N. [Univ. of Central Florida, Cocoa, FL (United States). Florida Solar Energy Center; Manikowski, A.; Noland, G. [Procyon Power Systems Inc., Alameda, CA (United States)

    2002-07-01

    The United States will soon need an increase in electric generating capacity along with an increase in the distribution capacity of the electricity grid. The cost and time required to build additional electrical distribution and transmission systems can be avoided by using distributed power generation. This paper examines the development of an integrated stand-alone energy system that can produce hydrogen, electricity and heat. The concept is based on integrated operation of a thermocatalytic pyrolysis (TCP) reactor and a solid oxide fuel cell (SOFC). The benefits include high overall energy efficiency, the production of high quality hydrogen (90 to 95 per cent free of carbon oxides), low emissions, and fuel flexibility. Experimental data is presented regarding the thermocatalytic pyrolysis of methane compared with an iron-based catalyst (which is sulfur resistant) and gasification of the resulting carbon with steam and carbon dioxide. With distributed generation, additional electrical generating capacity can be added in small increments distributed over the grid. An integrated energy system will be applicable to any type of hydrocarbon fuel, such as natural gas, liquid propane gas, gasoline, kerosene, jet fuel, diesel fuel and sulfurous residual oils. The suitable range of operating parameters needed to decoke a catalyst bed using steam and carbon dioxide as a degasifying agent was also determined. The Fe-catalyst was efficient in both methane pyrolysis and steam/CO{sub 2} gasification of carbon. It was shown that the TCP and SOFC complement each other in may ways. With the IES, high quality hydrogen is delivered to the end user. IES can also operate as either a hydrogen production unit or as an electrical power generator. The energy efficiency of the IES is estimated at 45-55 per cent. 6 refs., 8 figs.

  10. ENERGY EFFICIENCY, ENERGY SAVING POTENTIAL AND ENVIRONMENTAL IMPACT RESEARCH OF LPG CARRIER REFRIGERATION SYSTEM

    Directory of Open Access Journals (Sweden)

    V. О. Bedrosov

    2016-12-01

    Full Text Available Nowadays energy efficiency improvement and global warming are issues of current interest because of the natural resources depletion and extreme climate change. Thus, the problem of formation of strict regulations regarding emissions into the air arises. This paper presents the study of cascade refrigeration system for re-condensing of associated petroleum gas during sea transportation for LPG carrier. The structural optimization has been performed. LPG gas carriers with 266 000 m3 ethane capacity require 15 MW cascade refrigeration system for re-condensing if the temperature in the coastal LPG storage is -70°C, and the temperature for transported Ethan is maintained at  -75°C. For current storage conditions the required system cooling capacity is only 1,078 MW intended for the heat gain rejection from the environment during Ethane transportation. The replacement of ozone-depleting refrigerant R22 to alternative agents: R407C, R404A, R402A, R717, R290, R1270 was estimated. The results of analysis have shown that the proposed improvements can be used to optimize the LPG carrier cascade refrigeration system

  11. Hydrogen charging/discharging system with liquid organic compounds: a lacunar oxide catalyst to hydrogenate the unsaturated organic compound

    International Nuclear Information System (INIS)

    Jalowiecki-Duhamel, L.; Carpentier, J.; Payen, E.; Heurtaux, F.

    2006-01-01

    Lacunar mixed oxides based on cerium nickel and aluminium or zirconium CeM 0.5 Ni x O y s (M = Zr or Al), able to store high quantities of hydrogen, have been analysed in the hydrogenation of toluene into methyl-cyclohexane (MCH). When these solids present very good toluene hydrogenation activity and selectivity towards MCH in presence of H 2 , in absence of gaseous hydrogen, the reactive hydrogen species stored in the solid can hydrogenate toluene into MCH. The hydrogenation activity under helium + toluene flow decreases as a function of time and becomes nil. The integration of the curve obtained allows to determine the extractable hydrogen content of the solid used, and a value of 1.2 wt % is obtained at 80 C on a CeAl 0.5 Ni 3 O y compound pre-treated in H 2 at 300 C. To optimise the system, different parameters have been analysed, such as the catalyst formulation, the metal content, the pre-reducing conditions as well as the reaction conditions under helium + toluene. (authors)

  12. Pneumatic hydrogen pellet injection system for the ISX tokamak

    International Nuclear Information System (INIS)

    Milora, S.L.; Foster, C.A.

    1979-01-01

    We describe the design and operation of the solid hydrogen pellet injection system used in plasma refueling experiments on the ISX tokamak. The gun-type injector operates on the principle of gas dynamic acceleration of cold pellets confined laterally in a tube. The device is cooled by flowing liquid helium refrigerant, and pellets are formed in situ. Room temperature helium gas at moderate pressure is used as the propellant. The prototype device injected single hydrogen pellets into the tokamak discharge at a nominal 330 m/s. The tokamak plasma fuel content was observed to increase by (0.5--1.2) x 10 19 particles subsequent to pellet injection. A simple modification to the existing design has extended the performance to 1000 m/s. At higher propellant operating pressures (28 bars), the muzzle velocity is 20% less than predicted by an idealized constant area expansion process

  13. Influence of Inter Carrier Interference on Link Adaptation Algorithms in OFDM Systems

    DEFF Research Database (Denmark)

    Das, Suvra S.; Rahman, Muhammad Imadur; Wang, Yuanye

    2007-01-01

    The performance of Link Adaptation (LA) under the influence of inter carrier interference (ICI), which is cause by carrier frequency offset (CFO) and Doppler frequency spread due to mobility, in orthogonal frequency division multiplexing (OFDM) based wireless systems is analyzed in this work. LA...... maximizes throughput while maintaining a target bit error rate (BER)or Block Error Rate (BLER) at the receiver using the signal to noise ratio (SNR) fed back from the receiver to the transmitter. Since ICI power is proportional to the signal strength, the implications of such an impairment on LA OFDM...... can over the problem. It is also noted that ICI severely reduces the spectral efficiency of OFDM systems even when LA is used....

  14. Thermal design and technical economical and environmental analyses of a hydrogen fired multi-objective cogeneration system

    International Nuclear Information System (INIS)

    Durmaz, A; Yilmazoglu, M. Z.; Pasoglu, A.

    2007-01-01

    Approximately 85% of rapidly increasing world energy demand is supplied by fossil fuels. Extreme usage of fossil fuels causes serious global warming and environmental problems in form of air, soil and water pollutions. The period, in which fossil fuel reserves are decreasing, energy costs are increasing rapidly and new energy sources and technologies do not exist on the horizon, can be called as the expensive and critical energy period. Hydrogen becomes a matter of primary importance as a candidate energy source and carrier in the critical energy period and beyond to solve the energy and environmental problems radically. In this respect, the main obstacle for the use of hydrogen is the high cost of hydrogen production, which is expected to be decreased in the feature. The aim of this study is to examine how hydrogen energy will be able to be integrated with the existing energy substructure with technical and economical dimensions. In this sense, a multi objective hydrogen fired gas turbine cogeneration system is designed and optimized. Technical and economical analyses depending on the load conditions and different hydrogen production cost are carried out. It is possible that the co-generated heat is to be marketed for residence and industrial plants in the surrounding at or under market prices. The produced electricity however can only be sold to the public grid at a high unit support price which is only obtainable in case of the development of new energy technologies. This price should however be kept within the nowadays supportable energy price range. The main mechanism to be used during the design stage of the system to achieve this goal is to decrease the amortization and operational costs which lead to decrease investment and fuel costs and to increase the system load factor and co-generated heat revenues

  15. Simulation Performance of Multiple-Input Multiple-Output Systems Employing Single-Carrier Modulation and Orthogonal Frequency Division Multiplexing

    National Research Council Canada - National Science Library

    Saglam, Halil D

    2004-01-01

    ...) systems utilizing Alamouti-based space-time block coding (STBC) technique. The MIMO communication systems using STBC technique employing both single-carrier modulation and orthogonal frequency division multiplexing (OFDM...

  16. Hybrid vehicle system studies and optimized hydrogen engine design

    Science.gov (United States)

    Smith, J. R.; Aceves, S.

    1995-04-01

    We have done system studies of series hydrogen hybrid automobiles that approach the PNGV design goal of 34 km/liter (80 mpg), for 384 km (240 mi) and 608 km (380 mi) ranges. Our results indicate that such a vehicle appears feasible using an optimized hydrogen engine. We have evaluated the impact of various on-board storage options on fuel economy. Experiments in an available engine at the Sandia CRF demonstrated NO(x) emissions of 10 to 20 ppM at an equivalence ratio of 0.4, rising to about 500 ppm at 0.5 equivalence ratio using neat hydrogen. Hybrid simulation studies indicate that exhaust NO(x) concentrations must be less than 180 ppM to meet the 0.2 g/mile ULEV or Federal Tier II emissions regulations. LLNL has designed and fabricated a first generation optimized hydrogen engine head for use on an existing Onan engine. This head features 15:1 compression ratio, dual ignition, water cooling, two valves and open quiescent combustion chamber to minimize heat transfer losses. Initial testing shows promise of achieving an indicated efficiency of nearly 50% and emissions of less than 100 ppM NO(x). Hydrocarbons and CO are to be measured, but are expected to be very low since their only source is engine lubricating oil. A successful friction reduction program on the Onan engine should result in a brake thermal efficiency of about 42% compared to today's gasoline engines of 32%. Based on system studies requirements, the next generation engine will be about 2 liter displacement and is projected to achieve 46% brake thermal efficiency with outputs of 15 kW for cruise and 40 kW for hill climb.

  17. H/D Isotope Effects in Hydrogen Bonded Systems

    Directory of Open Access Journals (Sweden)

    Aleksander Filarowski

    2013-04-01

    Full Text Available An extremely strong H/D isotope effect observed in hydrogen bonded A-H…B systems is connected with a reach diversity of the potential shape for the proton/deuteron motion. It is connected with the anharmonicity of the proton/deuteron vibrations and of the tunneling effect, particularly in cases of short bridges with low barrier for protonic and deuteronic jumping. Six extreme shapes of the proton motion are presented starting from the state without possibility of the proton transfer up to the state with a full ionization. The manifestations of the H/D isotope effect are best reflected in the infra-red absorption spectra. A most characteristic is the run of the relationship between the isotopic ratio nH/nD and position of the absorption band shown by using the example of NHN hydrogen bonds. One can distinguish a critical range of correlation when the isotopic ratio reaches the value of ca. 1 and then increases up to unusual values higher than . The critical range of the isotope effect is also visible in NQR and NMR spectra. In the critical region one observes a stepwise change of the NQR frequency reaching 1.1 MHz. In the case of NMR, the maximal isotope effect is reflected on the curve presenting the dependence of Δd (1H,2H on d (1H. This effect corresponds to the range of maximum on the correlation curve between dH and ΔpKa that is observed in various systems. There is a lack in the literature of quantitative information about the influence of isotopic substitution on the dielectric properties of hydrogen bond except the isotope effect on the ferroelectric phase transition in some hydrogen bonded crystals.

  18. Band gap tunning in BN-doped graphene systems with high carrier mobility

    KAUST Repository

    Kaloni, T. P.

    2014-02-17

    Using density functional theory, we present a comparative study of the electronic properties of BN-doped graphene monolayer, bilayer, trilayer, and multilayer systems. In addition, we address a superlattice of pristine and BN-doped graphene. Five doping levels between 12.5% and 75% are considered, for which we obtain band gaps from 0.02 eV to 2.43 eV. We demonstrate a low effective mass of the charge carriers.

  19. CHARACTERIZATION OF TERNARY SYSTEM OF POORLY SOLUBLE DRUG IN VARIOUS HYDROPHILIC CARRIERS

    OpenAIRE

    Vijay Kumar; Shankaraiah MM; Venkatesh JS; Rangaraju D; C.Nagesh

    2011-01-01

    The present study aims to experiment the solid dispersion of poorly water soluble drug fenbendazole as model drug. Fenbendazole is an Antihelmintic drug (BCS class 2).The purpose of this study was to enhance the dissolution of Fenbendazole by solid dispersions consisting of the drug, a polymeric carrier, Binary and ternary system were prepared by kneading method using hydrophilic polymers like polyvinylpyrrolidone K-25 (PVP K25), beta-cyclodextrin (BCD),mannitol and urea. The prepared form...

  20. Hydrogen and fuel cell research: Institute for Integrated Energy Systems (IESVic)

    International Nuclear Information System (INIS)

    Pitt, L.

    2006-01-01

    Vision: IESVic's mission is to chart feasible paths to sustainable energy. Current research areas of investigation: 1. Energy system analysis 2. Computational fuel cell engineering; Fuel cell parameter measurement; Microscale fuel cells 3. Hydrogen dispersion studies for safety codes 4. Active magnetic refrigeration for hydrogen liquifaction and heat transfer in metal hydrides 5. Hydrogen and fuel cell system integration (author)

  1. New hydrogen technologies

    International Nuclear Information System (INIS)

    1992-01-01

    This report presents an overview of the overall hydrogen system. There are separate sections for production, distribution, transport, storage; and applications of hydrogen. The most important methods for hydrogen production are steam reformation of natural gas and electrolysis of water. Of the renewable energy options, production of hydrogen by electrolysis using electricity from wind turbines or by gasification of biomass were found to be the most economic for Finland. Direct use of this electricity or the production of liquid fuels from biomass will be competing alternatives. When hydrogen is produced in the solar belt or where there is cheap hydropower it must be transported over long distances. The overall energy consumed for the transport is from 25 to 40 % of the initial available energy. Hydrogen storage can be divided into stationary and mobile types. The most economic, stationary, large scale hydrogen storage for both long and short periods is underground storage. When suitable sites are not available, then pressure vessels are the best for short period and liquid H 2 for long period. Vehicle storage of hydrogen is by either metal hydrides or liquid H 2 . Hydrogen is a very versatile energy carrier. It can be used to produce heat directly in catalytic burners without flame, to produce electricity in fuel cells with high efficiency for use in vehicles or for peak power shaving, as a fuel component with conventional fuels to reduce emissions, as a way to store energy and as a chemical reagent in reactions

  2. Hydrogen peroxide oxidant fuel cell systems for ultra-portable applications

    Science.gov (United States)

    Valdez, T. I.; Narayanan, S. R.

    2001-01-01

    This paper will address the issues of using hydrogen peroxide as an oxidant fuel in a miniature DMFC system. Cell performance for DMFC based fuel cells operating on hydrogen peroxide will be presented and discussed.

  3. Novel Handover Optimization with a Coordinated Contiguous Carrier Aggregation Deployment Scenario in LTE-Advanced Systems

    Directory of Open Access Journals (Sweden)

    Ibraheem Shayea

    2016-01-01

    Full Text Available The carrier aggregation (CA technique and Handover Parameters Optimization (HPO function have been introduced in LTE-Advanced systems to enhance system performance in terms of throughput, coverage area, and connection stability and to reduce management complexity. Although LTE-Advanced has benefited from the CA technique, the low spectral efficiency and high ping-pong effect with high outage probabilities in conventional Carrier Aggregation Deployment Scenarios (CADSs have become major challenges for cell edge User Equipment (UE. Also, the existing HPO algorithms are not optimal for selecting the appropriate handover control parameters (HCPs. This paper proposes two solutions by deploying a Coordinated Contiguous-CADS (CC-CADS and a Novel Handover Parameters Optimization algorithm that is based on the Weight Performance Function (NHPO-WPF. The CC-CADS uses two contiguous component carriers (CCs that have two different beam directions. The NHPO-WPF automatically adjusts the HCPs based on the Weight Performance Function (WPF, which is evaluated as a function of the Signal-to-Interference Noise Ratio (SINR, cell load, and UE’s velocity. Simulation results show that the CC-CADS and the NHPO-WPF algorithm provide significant enhancements in system performance over that of conventional CADSs and HPO algorithms from the literature, respectively. The integration of both solutions achieves even better performance than scenarios in which each solution is considered independently.

  4. [Advances in novel carrier systems of chemical constituents from spice volatile oils].

    Science.gov (United States)

    Zhang, Jia-jia; Zhu, Yuan; Yu, Jiang-nan; Xu, Xi-ming

    2015-10-01

    Recent years, chemical constituents from spice volatile oils have gained worldwide concern owing to its multiple pharmacological effects and safety for using as the natural antibacterial agents. However, their poor dissolution, strong volatility, serious irritation, weak stability, easy oxidation and low bioavailability characteristics are the major obstacle in the preparation of effective oral formulation and practical application. Therefore, there is an urgent need to select a novel carrier system that can delivery the chemical constituents from spice volatile oils more efficiently with improving their stability as well as alleviating the irritation, and develop the functional food, health products and even medicine for exerting their pharmacological effects, which also is the focus and nodus of the research on their application. This review presents recent systematic studies on their novel carrier systems, including cyclodextrin inclusion complex, liposomes, nanoemulsions, nanoparticles, solid dispersion and so on, and summarizes the characteristics, application range and problems of each novel carrier systems, in order to provide some beneficial thoughts in further developing new products of chemical constituents from spice volatile oils.

  5. Large scale gas chromatographic demonstration system for hydrogen isotope separation

    International Nuclear Information System (INIS)

    Cheh, C.H.

    1988-01-01

    A large scale demonstration system was designed for a throughput of 3 mol/day equimolar mixture of H,D, and T. The demonstration system was assembled and an experimental program carried out. This project was funded by Kernforschungszentrum Karlsruhe, Canadian Fusion Fuel Technology Projects and Ontario Hydro Research Division. Several major design innovations were successfully implemented in the demonstration system and are discussed in detail. Many experiments were carried out in the demonstration system to study the performance of the system to separate hydrogen isotopes at high throughput. Various temperature programming schemes were tested, heart-cutting operation was evaluated, and very large (up to 138 NL/injection) samples were separated in the system. The results of the experiments showed that the specially designed column performed well as a chromatographic column and good separation could be achieved even when a 138 NL sample was injected

  6. Hydrogen perspectives in Japan

    International Nuclear Information System (INIS)

    Furutani, H.

    2000-01-01

    Hydrogen energy is considered to present a potential effective options for achieving the greenhouse gas minimization. The MITI (Ministry of International Trade and Industry) of Japanese Government is promoting the WE-NET (World Energy Network System) Project which envisions (1) construction of a global energy network for effective supply, transportation, storage and utilization of renewable energy using hydrogen as an energy carrier as a long-term options of sustainable energy economy, and (2) promotion of market entry of hydrogen energy in near and/or mid future even before construction of a WE-NET system. In this paper, I would like to report how far the hydrogen energy technology development addressed under Phase I has progressed, and describe the outline of the Phase II Plan. (author)

  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. 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.

  9. Hydrogenation of liquid natural rubber via diimide reduction in hydrazine hydrate/hydrogen peroxide system

    International Nuclear Information System (INIS)

    Yusof, Muhammad Jefri Mohd; Jamaluddin, Naharullah; Abdullah, Ibrahim; Yusoff, Siti Fairus M.

    2015-01-01

    Liquid natural rubber (LNR) with molecular weight of lower than 10 5 and shorter polymeric chain than natural rubber was prepared. LNR was then hydrogenated via diimide reduction by oxidation of hydrazine hydrate with hydrogen peroxide. The unsaturated units of the rubber were converted into saturated hydrocarbon to strengthen the backbone of the polymer so it was able to resist thermal degradation. The results indicated that hydrogenation degree of the product (HLNR) could be extended to 91.2% conversion under appropriate conditions. The hydrogenated LNR (HLNR) was characterized using Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The physical characteristics of HLNR were analyzed with Termogravimetric Analysis (TGA)

  10. Hydrogenation of liquid natural rubber via diimide reduction in hydrazine hydrate/hydrogen peroxide system

    Science.gov (United States)

    Yusof, Muhammad Jefri Mohd; Jamaluddin, Naharullah; Abdullah, Ibrahim; Yusoff, Siti Fairus M.

    2015-09-01

    Liquid natural rubber (LNR) with molecular weight of lower than 105 and shorter polymeric chain than natural rubber was prepared. LNR was then hydrogenated via diimide reduction by oxidation of hydrazine hydrate with hydrogen peroxide. The unsaturated units of the rubber were converted into saturated hydrocarbon to strengthen the backbone of the polymer so it was able to resist thermal degradation. The results indicated that hydrogenation degree of the product (HLNR) could be extended to 91.2% conversion under appropriate conditions. The hydrogenated LNR (HLNR) was characterized using Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The physical characteristics of HLNR were analyzed with Termogravimetric Analysis (TGA).

  11. Hydrogenation of liquid natural rubber via diimide reduction in hydrazine hydrate/hydrogen peroxide system

    Energy Technology Data Exchange (ETDEWEB)

    Yusof, Muhammad Jefri Mohd; Jamaluddin, Naharullah; Abdullah, Ibrahim; Yusoff, Siti Fairus M. [School of Chemical Sciences and Food Technology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

    2015-09-25

    Liquid natural rubber (LNR) with molecular weight of lower than 10{sup 5} and shorter polymeric chain than natural rubber was prepared. LNR was then hydrogenated via diimide reduction by oxidation of hydrazine hydrate with hydrogen peroxide. The unsaturated units of the rubber were converted into saturated hydrocarbon to strengthen the backbone of the polymer so it was able to resist thermal degradation. The results indicated that hydrogenation degree of the product (HLNR) could be extended to 91.2% conversion under appropriate conditions. The hydrogenated LNR (HLNR) was characterized using Fourier-Transform Infrared (FTIR) and Nuclear Magnetic Resonance (NMR) spectroscopy. The physical characteristics of HLNR were analyzed with Termogravimetric Analysis (TGA)

  12. Combating Impairments in Multi-carrier Systems: A Compressed Sensing Approach

    KAUST Repository

    Al-Shuhail, Shamael

    2015-05-01

    Multi-carrier systems suffer from several impairments, and communication system engineers use powerful signal processing tools to combat these impairments and keep up with the capacity/rate demands. Compressed sensing (CS) is one such tool that allows recovering any sparse signal, requiring only a few measurements in a domain that is incoherent with the domain of sparsity. Almost all signals of interest have some degree of sparsity, and in this work we utilize the sparsity of impairments in orthogonal frequency division multiplexing (OFDM) and its variants (i.e., orthogonal frequency division multiplexing access (OFDMA) and single-carrier frequency-division multiple access (SC-FDMA)) to combat them using CS. We start with the problem of peak-to-average power ratio (PAPR) reduction in OFDM. OFDM signals suffer from high PAPR and clipping is the simplest PAPR reduction scheme. However, clipping introduces inband distortions that result in compromised performance and hence needs to be mitigated at the receiver. Due to the high PAPR nature of the OFDM signal, only a few instances are clipped, these clipping distortions can be recovered at the receiver by employing CS. We then extend the proposed clipping recovery scheme to an interleaved OFDMA system. Interleaved OFDMA presents a special structure that result in only self-inflicted clipping distortions. In this work, we prove that distortions do not spread over multiple users (while utilizing interleaved carrier assignment in OFDMA) and construct a CS system that recovers the clipping distortions on each user. Finally, we address the problem of narrowband interference (NBI) in SC-FDMA. Unlike OFDM and OFDMA systems, SC-FDMA does not suffer from high PAPR, but (as the data is encoded in time domain) is seriously vulnerable to information loss owing to NBI. Utilizing the sparse nature of NBI (in frequency domain) we combat its effect on SC-FDMA system by CS recovery.

  13. A study on hazard types occurring in hydrogen facilities

    International Nuclear Information System (INIS)

    Cho, Nam Chul; Jae, Moo Sung; Eon, Yang Joon

    2004-01-01

    Hydrogen has ideal characteristics as an energy carrier. Hydrogen can be used as a clean fuel in a variety of energy end-use sectors including the conversion to electricity. After combustion, it produces only water. Therefore, the concept of hydrogen energy system has attracted much interest worldwide. But hydrogen has a defect that the explosion risk is high to an inflammable gas of a colorless, tasteless and odorless. Therefore, to use the hydrogen to the source of energy, hydrogen accident sequences and causes analysis must be needed. For this, hazard types occurring in hydrogen facilities have been considered through the case of domestic and foreign hydrogen accident in this study and hazard types to be considered are ignition, leaks, hydrogen dispersion, fire an explosion, storage vessel failure, vent and exhaust system, purging, condensation of air, hydrogen embrittlement, physiological hazard, and collisions during transportation

  14. Partial PIC-MRC Receiver Design for Single Carrier Block Transmission System over Multipath Fading Channels

    Directory of Open Access Journals (Sweden)

    Juinn-Horng Deng

    2012-01-01

    Full Text Available Single carrier block transmission (SCBT system has become one of the most popular modulation systems due to its low peak-to-average power ratio (PAPR, and it is gradually considered to be used for uplink wireless communication systems. In this paper, a low complexity partial parallel interference cancellation (PIC with maximum ratio combining (MRC technology is proposed to use for receiver to combat the intersymbol interference (ISI problem over multipath fading channel. With the aid of MRC scheme, the proposed partial PIC technique can effectively perform the interference cancellation and acquire the benefit of time diversity gain. Finally, the proposed system can be extended to use for multiple antenna systems to provide excellent performance. Simulation results reveal that the proposed low complexity partial PIC-MRC SIMO system can provide robust performance and outperform the conventional PIC and the iterative frequency domain decision feedback equalizer (FD-DFE systems over multipath fading channel environment.

  15. Standard Hydrogen Monitoring System-D operation and maintenance manual

    International Nuclear Information System (INIS)

    Schneider, T.C.

    1997-01-01

    The purpose of this document is to provide information for the operation and maintenance of the Standard Hydrogen Monitoring System-D (SHMS-D) used in the 200E and 200W area tank farms on the Hanford Site. This provides information specific to the mechanical operation of the system and is not intended to take the place of a Plant Operating Procedure. However, it does provide more information on the system than a Plant Operating Procedure. The intent here is that the system is started up by a technician or engineer who has completed tank farms training course No. 351405, and then the only actions performed by Operations will be routine log taking. If any problems not addressed by the operating procedure are encountered with the unit, engineering should be contacted

  16. Standard hydrogen monitoring system - E operation and maintenance manual

    International Nuclear Information System (INIS)

    Schneider, T.C.

    1997-01-01

    The purpose of this document is to provide information for the operation and maintenance of the Standard Hydrogen Monitoring System- E (SHMS-E) used in the 200E and 20OW area tank farms on the Hanford Site. This provides information specific to the mechanical operation of the system and is not intended to take the place of a Plant Operating Procedure. However, it does provide more information on the system than a Plant Operating Procedure. The intent here is that the system is started up by a technician or engineer who has completed tank farms training course for SHMS, and then the only actions performed by Operations will be routine log taking. If any problems not addressed by the operating procedure are encountered with the unit, engineering should be contacted

  17. Uplink Contention-based CSI Feedback with Prioritized Layers for a Multi-Carrier System

    DEFF Research Database (Denmark)

    Kaneko, Megumi; Hayashi, Kazunori; Popovski, Petar

    2012-01-01

    , several works have considered contention-based CSI feedback in the UL control channel. We propose such a feedback scheme for a generic MC system, based on the idea of variable collision protection, where the probability that a feedback information experiences a collision depends on its importance......Optimized resource allocation of the Downlink (DL) in wireless systems utilizing Multi-Carrier (MC) transmission requires Channel State Information (CSI) feedback for each user/subchannel to the Base Station (BS), consuming a high amount of Uplink (UL) radio resources. To alleviate this problem...

  18. The Aviation System Analysis Capability Air Carrier Cost-Benefit Model

    Science.gov (United States)

    Gaier, Eric M.; Edlich, Alexander; Santmire, Tara S.; Wingrove, Earl R.., III

    1999-01-01

    To meet its objective of assisting the U.S. aviation industry with the technological challenges of the future, NASA must identify research areas that have the greatest potential for improving the operation of the air transportation system. Therefore, NASA is developing the ability to evaluate the potential impact of various advanced technologies. By thoroughly understanding the economic impact of advanced aviation technologies and by evaluating how the new technologies will be used in the integrated aviation system, NASA aims to balance its aeronautical research program and help speed the introduction of high-leverage technologies. To meet these objectives, NASA is building the Aviation System Analysis Capability (ASAC). NASA envisions ASAC primarily as a process for understanding and evaluating the impact of advanced aviation technologies on the U.S. economy. ASAC consists of a diverse collection of models and databases used by analysts and other individuals from the public and private sectors brought together to work on issues of common interest to organizations in the aviation community. ASAC also will be a resource available to the aviation community to analyze; inform; and assist scientists, engineers, analysts, and program managers in their daily work. The ASAC differs from previous NASA modeling efforts in that the economic behavior of buyers and sellers in the air transportation and aviation industries is central to its conception. Commercial air carriers, in particular, are an important stakeholder in this community. Therefore, to fully evaluate the implications of advanced aviation technologies, ASAC requires a flexible financial analysis tool that credibly links the technology of flight with the financial performance of commercial air carriers. By linking technical and financial information, NASA ensures that its technology programs will continue to benefit the user community. In addition, the analysis tool must be capable of being incorporated into the

  19. Structural response of cargo containment systems in LNG carriers under ice loads

    International Nuclear Information System (INIS)

    Wang, B.; Yu, H.; Basu, R.; Lee, H.; Kwon, J.C.; Jeon, B.Y.; Kim, J.H.; Daley, C.; Kendrick, A.

    2008-01-01

    Gas exploration has been extended into the Arctic region such as in the Russian Arctic area, because of the increasing demand for energy resources. As a result, shipping in ice-covered seas is also increasing. Many technical issues are involved in ensuring the safety of liquefied natural gas (LNG) ships during the transportation. This paper discussed an investigation of ship-ice interaction scenarios for possible operation routes in Arctic areas. Six scenarios were selected to study the structural response of cargo containment systems (CCS) in both membrane and spherical types of LNG ships. For selected ship-ice interaction scenarios, ice loads and loading areas in the hull structure were determined based on the energy theory. The configurations of LNG carriers were discussed and illustrated. The paper also outlined the assessment criteria and structure analysis procedures. It was concluded that the strength of the CCS of membrane-type LNG carrier and the strength of the skirt structure of spherical-type LNG carrier were strong enough under the design ice loads. 13 refs., 9 tabs., 18 figs

  20. Hydrogen Macro System Model User Guide, Version 1.2.1

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, M.; Diakov, V.; Sa, T.; Goldsby, M.; Genung, K.; Hoseley, R.; Smith, A.; Yuzugullu, E.

    2009-07-01

    The Hydrogen Macro System Model (MSM) is a simulation tool that links existing and emerging hydrogen-related models to perform rapid, cross-cutting analysis. It allows analysis of the economics, primary energy-source requirements, and emissions of hydrogen production and delivery pathways.

  1. Evaluation of hydrogen production system coupling with HTTR using dynamic analysis code

    International Nuclear Information System (INIS)

    Sato, Hiroyuki; Ohashi, Hirofumi; Inaba, Yoshitomo; Nishihara, Tetsuo; Hayashi, Koji; Inagaki, Yoshiyuki

    2006-01-01

    The Japan Atomic Energy Agency (JAEA) was entrusted 'Development of Nuclear Heat Utilization Technology' by Ministry of Education, Culture, Sports, Science and Technology. In this development, the JAEA investigated the system integration technology to couple the hydrogen production system by steam reforming with the High Temperature Engineering Test Reactor (HTTR). Prior to the construction of the hydrogen production system coupling with the HTTR, a dynamic analysis code had to be developed to evaluate the system transient behaviour of the hydrogen production system because there are no examples of chemical facilities coupled with nuclear reactor in the world. This report describes the evaluation of the hydrogen production system coupling with HTTR using analysis code, N-HYPAC, which can estimate transient behaviour of the hydrogen production system by steam reforming. The results of this investigation provide that the influence of the thermal disturbance caused by the hydrogen production system on the HTTR can be estimated well. (author)

  2. Status Of Nuclear Heat And Hydrogen Systems Concept Study

    International Nuclear Information System (INIS)

    Lee, Won Jae; Choi, Yoon Ho; Han, Jae Mun; Ham, Jin Ki; Choi, Su Jin; Lee, Sang Il; Park, Je Ho; Koo, Jae Sak

    2014-01-01

    A three-year national research and development project, “Nuclear Heat and Hydrogen (NuH_2) Systems Concept Study” was launched in 2012 as a pre-project in preparation of a demonstration plant construction and subsequent commercialization. Korea Atomic Energy Research Institute (KAERI) leads the project, and domestic industry partners, POSCO, HDEC, HHI, HEC and STX, as potential vendors and users share the costs and works. The main tasks are to develop the functional and design requirements, to optimize the system concepts and layouts, and to develop the demonstration plan and business model of the NuH_2 systems. This paper addresses the current status of the project and outcomes. (author)

  3. Solar-hydrogen energy systems: an authoritative review of water-splitting systems by solar beam and solar heat : hydrogen production, storage, and utilisation

    National Research Council Canada - National Science Library

    Ōta, Tokio

    1979-01-01

    ... An Authoritative Review of Watersplitting Systems by Solar Beam and Solar Heat: Hydrogen Production, Storage and Utilisation edited by TOKIO OHTA Professor of Materials Science and Energy System Yoko...

  4. Hydrogen atom as a quantum-classical hybrid system

    International Nuclear Information System (INIS)

    Zhan, Fei; Wu, Biao

    2013-01-01

    Hydrogen atom is studied as a quantum-classical hybrid system, where the proton is treated as a classical object while the electron is regarded as a quantum object. We use a well known mean-field approach to describe this hybrid hydrogen atom; the resulting dynamics for the electron and the proton is compared to their full quantum dynamics. The electron dynamics in the hybrid description is found to be only marginally different from its full quantum counterpart. The situation is very different for the proton: in the hybrid description, the proton behaves like a free particle; in the fully quantum description, the wave packet center of the proton orbits around the center of mass. Furthermore, we find that the failure to describe the proton dynamics properly can be regarded as a manifestation of the fact that there is no conservation of momentum in the mean-field hybrid approach. We expect that such a failure is a common feature for all existing approaches for quantum-classical hybrid systems of Born-Oppenheimer type.

  5. Hydrogen treatment system in the Genkai nuclear power plant No. 2

    International Nuclear Information System (INIS)

    Nakamura, Masayuki; Kodama, Hideo; Murashima, Masayasu

    1977-01-01

    The new hydrogen treatment system which injects hydrogen into the volume control tank for purging the mixed waste gas of Kr, Xe, etc. is adopted in the Genkai nuclear power plant No. 2. The system is composed of mainly the waste gas pretreatment equipment, a palladium alloy membrane type hydrogen separator, a hydrogen compressor, and a waste gas decay tank. The outline of the primary cooling system and the chemical volume control system of PWR, the hydrogen treatment system, and the gaseous waste disposal system of original and new types for the Genkai nuclear power plants No. 1 and 2 are explained in this paper. This newly added hydrogen treatment system will be able to reduce the rare gas concentration rate in the primary coolant to about 1/2 and 1/5 for Kr 85 and Xe 133 , respectively. (auth.)

  6. Hydrogen-Based Energy Conservation System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — NASA and many others often rely on delivery of cryogenic hydrogen to meet their facility needs. NASA's Stennis Space Center is one of the largest users of hydrogen,...

  7. The Future of Nuclear Energy As a Primary Source for Clean Hydrogen Energy System in Developing Countries

    International Nuclear Information System (INIS)

    Ahmed, K.; Shaaban, H.

    2007-01-01

    The limited availability of fossil fuels compared to the increasing demand and the connected environmental questions have become topics of growing importance and international attention. Many other clean alternative sources of energy are available, but most of them are either relatively undeveloped technologically or are not yet fully utilized. Also, there is a need for a medium which can carry the produced energy to the consumer in a convenient and environmentally acceptable way. In this study, a fission reactor as a primary energy source with hydrogen as an energy carrier is suggested. An assessment of hydrogen production from nuclear energy is presented. A complete nuclear-electro-hydrogen energy system is proposed for a medium size city (population of 500,000). The whole energy requirement is assessed including residential, industrial and transportation energies. A preliminary economical and environmental impact study is performed on the proposed system. The presented work could be used as a nucleus for a feasibility study for applying this system in any newly established city

  8. Community Energy: Analysis of Hydrogen Distributed Energy Systems with Photovoltaics for Load Leveling and Vehicle Refueling

    Energy Technology Data Exchange (ETDEWEB)

    Steward, D.; Zuboy, J.

    2014-10-01

    Energy storage could complement PV electricity generation at the community level. Because PV generation is intermittent, strategies must be implemented to integrate it into the electricity system. Hydrogen and fuel cell technologies offer possible PV integration strategies, including the community-level approaches analyzed in this report: (1) using hydrogen production, storage, and reconversion to electricity to level PV generation and grid loads (reconversion scenario); (2) using hydrogen production and storage to capture peak PV generation and refuel hydrogen fuel cell electric vehicles (FCEVs) (hydrogen fueling scenario); and (3) a comparison scenario using a battery system to store electricity for EV nighttime charging (electric charging scenario).

  9. Techno-economic evaluation of hybrid systems for hydrogen production from biomass and natural gas

    Energy Technology Data Exchange (ETDEWEB)

    Kassem, N. [Royal Institute of Technology, Stockholm (Sweden). Dept. of Energy Processes

    2001-07-01

    Hydrogen (H{sub 2}) is an alternative energy carrier, which is expected to significantly contribute to globally sustainable energy systems. It is environmentally friendly with high-energy density that makes it an excellent integrating fuel in transportation and power generation systems. This paper presents an assessment of the techno-economic viability of H{sub 2} production technologies based on hybrid systems using gasified biomass and natural gas combined with high temperature electrochemical shift. Assessment of the well-established thermal processes, high-temperature steam electrolysis (HTEL), and the plasma catalytic reforming (PCR) of light hydrocarbons developed at MIT are included for comparison. The results show that the PCR and HTEL processes are as cost-effective as the thermal steam reforming for H{sub 2} production when deployed on a commercial scale. The natural gas steam reforming (NGSR) is still the most favorable choice in energy and financial terms, while gasified biomass (GB) provides the highest production costs due to the intensive capital cost investments. The cost of H{sub 2} storage in the form of compressed gas or liquefied H{sub 2} also contributes significantly to total cost per kg produced H{sub 2}. 9 refs., 7 figs., 2 tabs.

  10. Analysis of a gas absorption system with soluble carrier gas and volatile solvent

    International Nuclear Information System (INIS)

    Kanak, B.E.

    1980-01-01

    The effects of column diameter, carrier gas coabsorption, and solvent vaporization on the performance of a packed gas absorption column are examined. The system investigated employs dichlorodifluoromethane as a solvent to remove krypton from a nitrogen stream and is characterized by substantial nitrogen coabsorption. Three columns with diameters of 2, 3, and 4 inches were constructed and packed with 34.5 inches of Goodloe packing. In addition to the more conventional data, the experimental evaluation of these columns included the use of a radioisotope and a gamma scanning technique which provided direct measurement of the columns' molar krypton profiles. A multicomponent gas absorption model was developed, based on the two-film mass transfer theory, that allows the fluxes of all species to interact. Verification of this model was achieved through comparison of the calculated results with experimental data. With the feed gas flow rate between 6 and 36 lb moles/hr-ft 2 and the solvent feed rate between 40 and 400 lb moles/hr-ft 2 , column diameter was found to have no significant impact on the mass transfer efficiency of this system when carried out in columns with diameters of 2 inches or greater. The absorption of krypton was found to be enhanced and inhibited, respectively, by carrier gas coabsorption and solvent vaporization. An injector system to add gaseous solvent to the feed gas stream prior to its introduction into the packed bed was proposed to eliminate the detrimental effects of solvent vaporization.Using this injector to supersaturate the feed gas stream with solvent enhanced absorber performance in the same manner as carrier gas coabsorption

  11. Hydrogen as a fuel for today and tomorrow: expectations for advanced hydrogen storage materials/systems research.

    Science.gov (United States)

    Hirose, Katsuhiko

    2011-01-01

    History shows that the evolution of vehicles is promoted by several environmental restraints very similar to the evolution of life. The latest environmental strain is sustainability. Transport vehicles are now facing again the need to advance to use sustainable fuels such as hydrogen. Hydrogen fuel cell vehicles are being prepared for commercialization in 2015. Despite intensive research by the world's scientists and engineers and recent advances in our understanding of hydrogen behavior in materials, the only engineering phase technology which will be available for 2015 is high pressure storage. Thus industry has decided to implement the high pressure tank storage system. However the necessity of smart hydrogen storage is not decreasing but rather increasing because high market penetration of hydrogen fuel cell vehicles is expected from around 2025 onward. In order to bring more vehicles onto the market, cheaper and more compact hydrogen storage is inevitable. The year 2025 seems a long way away but considering the field tests and large scale preparation required, there is little time available for research. Finding smart materials within the next 5 years is very important to the success of fuel cells towards a low carbon sustainable world.

  12. Message-Passing Receivers for Single Carrier Systems with Frequency-Domain Equalization

    DEFF Research Database (Denmark)

    Zhang, Chuanzong; Manchón, Carles Navarro; Wang, Zhongyong

    2015-01-01

    In this letter, we design iterative receiver algorithms for joint frequency-domain equalization and decoding in a single carrier system assuming perfect channel state information. Based on an approximate inference framework that combines belief propagation (BP) and the mean field (MF) approximation......, we propose two receiver algorithms with, respectively, parallel and sequential message-passing schedules in the MF part. A recently proposed receiver based on generalized approximate message passing (GAMP) is used as a benchmarking reference. The simulation results show that the BP-MF receiver...

  13. Multi-user MIMO and carrier aggregation in 4G systems

    DEFF Research Database (Denmark)

    Cattoni, Andrea Fabio; Nguyen, Hung Tuan; Duplicy, Jonathan

    2012-01-01

    The market success of broadband multimediaenabled devices such as smart phones, tablets, and laptops is increasing the demand for wireless data capacity in mobile cellular systems. In order to meet such requirements, the introduction of advanced techniques for increasing the efficiency in spectrum...... usage was required. Multi User -Multiple Input Multiple Output (MU-MIMO) and Carrier Aggregation (CA) are two important techniques addressed by 3GPP for LTE and LTE-Advanced. The aim of the EU FP7 project on ”Spectrum Aggregation and Multiuser-MIMO: real-World Impact” (SAMURAI) is to investigate...

  14. Design progress of cryogenic hydrogen system for China Spallation Neutron Source

    Energy Technology Data Exchange (ETDEWEB)

    Wang, G. P.; Zhang, Y.; Xiao, J.; He, C. C.; Ding, M. Y.; Wang, Y. Q.; Li, N.; He, K. [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, P.R. (China)

    2014-01-29

    China Spallation Neutron Source (CSNS) is a large proton accelerator research facility with 100 kW beam power. Construction started in October 2011 and is expected to last 6.5 years. The cryogenic hydrogen circulation is cooled by a helium refrigerator with cooling capacity of 2200 W at 20 K and provides supercritical hydrogen to neutron moderating system. Important progresses of CSNS cryogenic system were concluded as follows. Firstly, process design of cryogenic system has been completed including helium refrigerator, hydrogen loop, gas distribution, and safety interlock. Secondly, an accumulator prototype was designed to mitigate pressure fluctuation caused by dynamic heat load from neutron moderation. Performance test of the accumulator has been carried out at room and liquid nitrogen temperature. Results show the accumulator with welding bellows regulates hydrogen pressure well. Parameters of key equipment have been identified. The contract for the helium refrigerator has been signed. Mechanical design of the hydrogen cold box has been completed, and the hydrogen pump, ortho-para hydrogen convertor, helium-hydrogen heat exchanger, hydrogen heater, and cryogenic valves are in procurement. Finally, Hydrogen safety interlock has been finished as well, including the logic of gas distribution, vacuum, hydrogen leakage and ventilation. Generally, design and construction of CSNS cryogenic system is conducted as expected.

  15. MCD 80: A modular coupling system for power line carrier transmission

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, B; Mayer, M

    1983-05-01

    Power line carrier (PLC) links are of great importance to power supply utilities. The communications equipment is linked to the H.V. system by a coupling device. Brown Boveri have developed a new modular coupling system MCD 80 which is compact, programmable and economical. The benefit of years of experience in the field went into its development. With the new system, optimum PLC couplings, R.F. through-connections and junction networks are possible for all H.V. transmission systems. A general look at the subject of PLC couplings is followed by a closer look at the main components, such as the programmable high pass coupling unit, band pass coupling unit, hybrid, separating filter, R.F. junction network and attenuator. Some typical examples are described.

  16. Carrier Current Line Systems Technologies in M2M Architecture for Wireless Communication

    Directory of Open Access Journals (Sweden)

    Hua-Ching Chen

    2016-01-01

    Full Text Available This paper investigates the Carrier Current Line Systems (CCLS technologies of Machine to Machine (M2M architecture which applied for mobile station coverage working with metro, high speed railway, and subway such as analysis for public transport of an indoor transition system. It is based on the theory and practical engineering principle which provide guidelines and formulas for link budget design to help designers fully control and analyze the single output power of uplink and downlink between Fiber Repeaters (FR and mobile station as well as base station. Finally, the results of this leakage cable system are successfully applied to indoor coverage design for metro rapid transit system which are easily installed cellular over fiber solutions for WCDMA/LTE access is becoming Ubiquitous Network to Internet of Thing (IOT real case hierarchy of telecommunication.

  17. The Design of Bulk Carrier Cargo Holds State Integrated Monitoring System

    Directory of Open Access Journals (Sweden)

    Gao Ru-jiang

    2016-01-01

    Full Text Available Most ship cargo hold Internal uses artificial watch or is unattended. Therefore, it is impossible to know the appropriate information of the cargo holds Internal timely and accurately. Cargo damage and ship accidents occurred frequently. Automation remote processing and monitoring alarm system for the bulk carrier is an important part of the marine automation. The system plays a significant role to guarantee the navigation safety for bulk carriers. The paper introduced the important parts of the integrated monitoring system, structural design, hardware configuration, various modules communication transmission and various data processing software design were included. Based on embedded development, the real time information including the cargo hold internal humidity temperature, oxygen concentration, smoke gas concentration, cold water well level and other data were collected, as well the hatch closed state was detected and the cargo hold internal real time video information was collected. Then the real-time communication between the control display and acquisition modules were assured. By adjusting the corresponding buttons on the bridge according to the monitoring information, so that the cargo hold always in a safe environment, so as to avoid cargo hold accidents.

  18. Hydrogen Storage using Metal Hydrides in a Stationary Cogeneration System

    International Nuclear Information System (INIS)

    Botzung, Maxime; Chaudourne, Serge; Perret, Christian; Latroche, Michel; Percheron-Guegan, Annick; Marty Philippe

    2006-01-01

    In the frame of the development of a hydrogen production and storage unit to supply a 40 kW stationary fuel cell, a metal hydride storage tank was chosen according to its reliability and high energetic efficiency. The study of AB5 compounds led to the development of a composition adapted to the project needs. The absorption/desorption pressures of the hydride at 75 C (2 / 1.85 bar) are the most adapted to the specifications. The reversible storage capacity (0.95 %wt) has been optimized to our work conditions and chemical kinetics is fast. The design of the Combined Heat and Power CHP system requires 5 kg hydrogen storage but in a first phase, only a 0.1 kg prototype has been realised and tested. Rectangular design has been chosen to obtain good compactness with an integrated plate fin type heat exchanger designed to reach high absorption/desorption rates. In this paper, heat and mass transfer characteristics of the Metal Hydride tank (MH tank) during absorption/desorption cycles are given. (authors)

  19. Analysis of an Improved Solar-Powered Hydrogen Generation System for Sustained Renewable Energy Production

    Science.gov (United States)

    2017-12-01

    hydrogen gas by electrolysis. In LT Aviles’ design , distilled water was collected from the ambient air using Peltier dehumidifiers, manufactured by...Figure 13 shows the shelfing along with the entire system. Figure 13. Reconfigured Hydrogen Production Facility Because the system was designed for...POWERED HYDROGEN GENERATION SYSTEM FOR SUSTAINED RENEWABLE ENERGY PRODUCTION by Sen Feng Yu December 2017 Thesis Advisor: Garth V. Hobson Co

  20. An Expert System Interfaced with a Database System to Perform Troubleshooting of Aircraft Carrier Piping Systems

    Science.gov (United States)

    1988-12-01

    interval of four feet, and are numbered sequentially bow to stem. * "wing tank" is a tank or void, outboard of the holding bulkhead, away from the center...system and DBMS simultaneously with a multi-processor, allowing queries to the DBMS without terminating the expert system. This method was judged...RECIRC). eductor -strip("Y"):- ask _ques _read_ans(OVBD,"ovbd dis open"),ovbd dis-open(OVBD). eductor-strip("N"):- ask_ques read_ans( LINEUP , "strip lineup

  1. TWRS hydrogen mitigation portable standard hydrogen monitoring system platform design and fabrication engineering task plan

    International Nuclear Information System (INIS)

    Philipp, B.L.

    1997-01-01

    The primary function of portable gas monitoring is to quickly determine tank vapor space gas composition and gas release rate, and to detect gas release events. Characterization of the gas composition is needed for safety analysis. The lower flammability limit, as well as the peak burn temperature and pressure, are dependent upon the gas composition. If there is little or no knowledge about the gas composition, safety analysis utilize compositions that yield the worst case in a deflagration or detonation. This conservative approach to unknowns necessitates a significant increase in administrative and engineering costs. Knowledge of the true composition could lead to reductions in the assumptions and therefore contribute to a reduction in controls and work restrictions. Also, knowledge of the actual composition will be required information for the analysis that is needed to remove tanks from the Watch List. Similarly, the rate of generation and release of gases is required information for performing safety analysis, developing controls, designing equipment, and closing safety issues. To determine release rate, both the gas concentrations and the dome space ventilation rates (exhauster flow rate or passive dome/atmosphere exchange rate) are needed. Therefore, to quickly verify waste tank categorization or to provide additional characterization for tanks with installed gas monitoring, a temporary, portable standard hydrogen monitoring system is needed that can be used to measure gas compositions at both high and low sensitivities

  2. Determination of hydrogen peroxide in water by chemiluminescence detection, (1). Flow injection type hydrogen peroxide detection system

    International Nuclear Information System (INIS)

    Yamashiro, Naoya; Uchida, Shunsuke; Satoh, Yoshiyuki; Morishima, Yusuke; Yokoyama, Hiroaki; Satoh, Tomonori; Sugama, Junichi; Yamada, Rie

    2004-01-01

    A flow injection type hydrogen peroxide detection system with a sub-ppb detection limit has been developed to determine hydrogen peroxide concentration in water sampled from a high temperature, high pressure hydrogen peroxide water loop. The hydrogen peroxide detector is based on luminol chemiluminescence spectroscopy. A small amount of sample water (20 μl) is mixed with a reagent mixture, an aqueous solution of luminol and Co 2+ catalyst, in a mixing cell which is installed just upstream from the detection cell. The optimum values for pH and the concentrations of luminol and Co 2+ ion have been determined to ensure a lower detectable limit and a higher reproducibility. The photocurrent detected by the detection system is expressed by a linear function of the hydrogen peroxide concentration in the region of lower concentration ([H 2 O 2 ] 2 O 2 ] in the region of higher concentration ([H 2 O 2 ] > 10 ppb). The luminous intensity of luminol chemiluminescence is the highest when pH of the reagent mixture is 11.0. Optimization of the major parameters gives the lowest detectable limit of 0.3 ppb. (author)

  3. Hydrogen bonding-mediated dehydrogenation in the ammonia borane combined graphene oxide systems

    Science.gov (United States)

    Kuang, Anlong; Liu, Taijuan; Kuang, Minquan; Yang, Ruifeng; Huang, Rui; Wang, Guangzhao; Yuan, Hongkuan; Chen, Hong; Yang, Xiaolan

    2018-03-01

    The dehydrogenation of ammonia borane (AB) adsorbed on three different graphene oxide (GO) sheets is investigated within the ab initio density functional theory. The energy barriers to direct combination the hydrogens of hydroxyl groups and the hydridic hydrogens of AB to release H2 are relatively high, indicating that the process is energetically unfavorable. Our theoretical study demonstrates that the dehydrogenation mechanism of the AB-GO systems has undergone two critical steps, first, there is the formation of the hydrogen bond (O-H-O) between two hydroxyl groups, and then, the hydrogen bond further react with the hydridic hydrogens of AB to release H2 with low reaction barriers.

  4. Computer based system for measuring the minority carrier lifetime in the solar cells

    International Nuclear Information System (INIS)

    Morales A, A.; Casados C, G.

    1994-01-01

    We show the development of a computer based system for measuring the minority carrier lifetime in the base of silicon solar cells. The system allows using two different techniques for such kind of measurements:the open circuit voltage decay (OCVD) and the surface voltage decay SVD. The equipment is based on internal cards for IBM-Pc or compatible computers that work as an oscilloscope and as a function generator, in addition to a synchronization and signal conditioning circuit. The system is fully controlled by a 'c' language program that optimizes the used of the instrument built in this way, and makes the analysis of the measurement data by curve fitting techniques. We show typical results obtained with silicon solar cells made in our laboratories. (Author)

  5. Phase separation in strongly correlated electron systems with two types of charge carriers

    International Nuclear Information System (INIS)

    Kugel, K.I.; Rakhmanov, A.L.; Sboychakov, A.O.

    2007-01-01

    Full text: A competition between the localization of the charge carriers due to Jahn-Teller distortions and the energy gain due to their delocalization in doped manganite and related magnetic oxides is analyzed based on a Kondo-lattice type model. The resulting effective Hamiltonian is, in fact, a generalization of the Falicov-Kimball model. We find that the number of itinerant charge carriers can be significantly lower than that implied by the doping level x. The phase diagram of the model in the T plane is constructed. The system exhibits magnetic ordered (antiferromagnetic, ferromagnetic, or canted) states as well the paramagnetic states with zero and nonzero density of the itinerant electrons. It is shown that a phase-separation is favorable in energy for a wide doping range. The characteristic size of inhomogeneities in a phase-separated state is of the order of several lattice constants. We also analyzed the two-band Hubbard model in the limit of strong on-site Coulomb repulsion. It was shown that such a system has a tendency to phase separation into the regions with different charge densities even in the absence of magnetic or any other ordering, if the ratio of the bandwidths is large enough. The work was supported by the European project CoMePhS and by the Russian Foundation for Basic Research, project no. 05-02-17600. (authors)

  6. Effect of hydrogen on the growth and morphology of single wall carbon nanotubes synthesized on a Fe-Mo/MgO catalytic system

    Energy Technology Data Exchange (ETDEWEB)

    Biris, Alexandru R. [National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj Napoca, RO-3400 (Romania)], E-mail: biris@oc1.itim-cj.ro; Li Zhongrui; Dervishi, Enkeleda [Applied Science Department, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204 (United States); Nanotechnology Center, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204 (United States); Lupu, Dan [National Institute for Research and Development of Isotopic and Molecular Technologies, Cluj Napoca, RO-3400 (Romania); Xu Yang; Saini, Viney [Applied Science Department, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204 (United States); Nanotechnology Center, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204 (United States); Watanabe, Fumiya [Nanotechnology Center, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204 (United States); Biris, Alexandru S. [Applied Science Department, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204 (United States); Nanotechnology Center, University of Arkansas at Little Rock, 2801 S. University Ave, Little Rock, AR 72204 (United States)], E-mail: asbiris@ualr.edu

    2008-04-21

    Single wall carbon nanotubes were synthesized from thermal pyrolysis of methane on a Fe-Mo/MgO catalyst by radio frequency catalytic chemical vapor deposition (RF-CVD) using argon as a carrier gas. Controlled amounts of hydrogen (H{sub 2}/CH{sub 4}=0-1 v/v) were introduced in separate experiments along with the carbon source. The properties and morphology of the synthesized single wall carbon nanotubes were monitored by transmission electron microscopy, Raman scattering, and thermogravimetric analysis. The nanotubes with the highest crystallinity were obtained with H{sub 2}/CH{sub 4}=0.6. By monitoring the Radial Breathing Modes present in the Raman spectra of the single-wall carbon nanotube samples, the variation of the structural and morphological properties of the carbon nanotubes with the flow level of hydrogen, reflect changes of the catalyst systems induced by the presence of hydrogen.

  7. Performance test results of mock-up test facility of HTTR hydrogen production system

    International Nuclear Information System (INIS)

    Ohashi, Hirofumi; Inaba, Yoshitomo; Nishihara, Tetsuo

    2004-01-01

    For the purpose to demonstrate effectiveness of high-temperature nuclear heat utilization, Japan Atomic Energy Research Institute has been developing a hydrogen production system and has planned to connect the hydrogen production system to High Temperature Engineering Test Reactor (HTTR). Prior to construction of a HTTR hydrogen production system, a mock-up test facility was constructed to investigate transient behavior of the hydrogen production system and to establish system controllability. The Mock-up test facility with a full-scale reaction tube is an approximately 1/30-scale model of the HTTR hydrogen production system and an electric heater is used as a heat source instead of a reactor. After its construction, a performance test of the test facility was carried out in the same pressure and temperature conditions as those of the HTTR hydrogen production system to investigate its performance such as hydrogen production ability, controllability and so on. It was confirmed that hydrogen was stably produced with a hot helium gas about 120m 3 /h, which satisfy the design value, and thermal disturbance of helium gas during the start-up could be mitigated within the design value by using a steam generator. The mock-up test of the HTTR hydrogen production system using this facility will continue until 2004. (author)

  8. Out-of-pile demonstration test of hydrogen production system coupling with HTTR

    Energy Technology Data Exchange (ETDEWEB)

    Inagaki, Yoshiyuki; Nishihara, Tetsuo; Takeda, Tetsuaki; Hada, Kazuhiko; Hayashi, Koji [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment

    1999-07-01

    In Japan Atomic Energy Research Institute, a hydrogen production system is being designed to produce hydrogen by means of a steam reforming process of natural gas using nuclear heat (10 MW, 905degC) supplied by the High Temperature Engineering Test Reactor (HTTR). The safety principle and criteria are also being investigated in the HTTR hydrogen production system. Prior to coupling of the steam reforming system with the HTTR, an out-of-pile demonstration test was planned to confirm safety, controllability and performance of the steam reforming system under simulated operational conditions of the HTTR hydrogen production system. The out-of-pile test facility simulates key components downstream an intermediate heat exchanger of the HTTR hydrogen production system on a scale of 1 to 30 has a hydrogen production capacity of 110 Nm{sup 3}/h using an electric heater as a reactor substitute. The test facility is under manufacturing aiming at completion in 2000 and followed by the test till 2004. In parallel to this, a hydrogen permeation test and a corrosion test of a catalyst tube of a steam reformer are being carried out to obtain data necessary for the design of the system. This report describes outline of the out-of-pile hydrogen production facility and demonstration test program for the HTTR hydrogen production system at present status. (author)

  9. Out-of-pile demonstration test of hydrogen production system coupling with HTTR

    International Nuclear Information System (INIS)

    Inagaki, Yoshiyuki; Nishihara, Tetsuo; Takeda, Tetsuaki; Hada, Kazuhiko; Hayashi, Koji

    1999-01-01

    In Japan Atomic Energy Research Institute, a hydrogen production system is being designed to produce hydrogen by means of a steam reforming process of natural gas using nuclear heat (10 MW, 905degC) supplied by the High Temperature Engineering Test Reactor (HTTR). The safety principle and criteria are also being investigated in the HTTR hydrogen production system. Prior to coupling of the steam reforming system with the HTTR, an out-of-pile demonstration test was planned to confirm safety, controllability and performance of the steam reforming system under simulated operational conditions of the HTTR hydrogen production system. The out-of-pile test facility simulates key components downstream an intermediate heat exchanger of the HTTR hydrogen production system on a scale of 1 to 30 has a hydrogen production capacity of 110 Nm 3 /h using an electric heater as a reactor substitute. The test facility is under manufacturing aiming at completion in 2000 and followed by the test till 2004. In parallel to this, a hydrogen permeation test and a corrosion test of a catalyst tube of a steam reformer are being carried out to obtain data necessary for the design of the system. This report describes outline of the out-of-pile hydrogen production facility and demonstration test program for the HTTR hydrogen production system at present status. (author)

  10. Stabilization of Wind Energy Conversion System with Hydrogen Generator by Using EDLC Energy Storage System

    Science.gov (United States)

    Shishido, Seiji; Takahashi, Rion; Murata, Toshiaki; Tamura, Junji; Sugimasa, Masatoshi; Komura, Akiyoshi; Futami, Motoo; Ichinose, Masaya; Ide, Kazumasa

    The spread of wind power generation is progressed hugely in recent years from a viewpoint of environmental problems including global warming. Though wind power is considered as a very prospective energy source, wind power fluctuation due to the random fluctuation of wind speed has still created some problems. Therefore, research has been performed how to smooth the wind power fluctuation. This paper proposes Energy Capacitor System (ECS) for the smoothing of wind power which consists of Electric Double-Layer Capacitor (EDLC) and power electronics devices and works as an electric power storage system. Moreover, hydrogen has received much attention in recent years from a viewpoint of exhaustion problem of fossil fuel. Therefore it is also proposed that a hydrogen generator is installed at the wind farm to generate hydrogen. In this paper, the effectiveness of the proposed system is verified by the simulation analyses using PSCAD/EMTDC.

  11. ACCEPTABILITY ENVELOPE FOR METAL HYDRIDE-BASED HYDROGEN STORAGE SYSTEMS

    Energy Technology Data Exchange (ETDEWEB)

    Hardy, B.; Corgnale, C.; Tamburello, D.; Garrison, S.; Anton, D.

    2011-07-18

    The design and evaluation of media based hydrogen storage systems requires the use of detailed numerical models and experimental studies, with significant amount of time and monetary investment. Thus a scoping tool, referred to as the Acceptability Envelope, was developed to screen preliminary candidate media and storage vessel designs, identifying the range of chemical, physical and geometrical parameters for the coupled media and storage vessel system that allow it to meet performance targets. The model which underpins the analysis allows simplifying the storage system, thus resulting in one input-one output scheme, by grouping of selected quantities. Two cases have been analyzed and results are presented here. In the first application the DOE technical targets (Year 2010, Year 2015 and Ultimate) are used to determine the range of parameters required for the metal hydride media and storage vessel. In the second case the most promising metal hydrides available are compared, highlighting the potential of storage systems, utilizing them, to achieve 40% of the 2010 DOE technical target. Results show that systems based on Li-Mg media have the best potential to attain these performance targets.

  12. Economics of Direct Hydrogen Polymer Electrolyte Membrane Fuel Cell Systems

    Energy Technology Data Exchange (ETDEWEB)

    Mahadevan, Kathyayani

    2011-10-04

    Battelle's Economic Analysis of PEM Fuel Cell Systems project was initiated in 2003 to evaluate the technology and markets that are near-term and potentially could support the transition to fuel cells in automotive markets. The objective of Battelle?s project was to assist the DOE in developing fuel cell systems for pre-automotive applications by analyzing the technical, economic, and market drivers of direct hydrogen PEM fuel cell adoption. The project was executed over a 6-year period (2003 to 2010) and a variety of analyses were completed in that period. The analyses presented in the final report include: Commercialization scenarios for stationary generation through 2015 (2004); Stakeholder feedback on technology status and performance status of fuel cell systems (2004); Development of manufacturing costs of stationary PEM fuel cell systems for backup power markets (2004); Identification of near-term and mid-term markets for PEM fuel cells (2006); Development of the value proposition and market opportunity of PEM fuel cells in near-term markets by assessing the lifecycle cost of PEM fuel cells as compared to conventional alternatives used in the marketplace and modeling market penetration (2006); Development of the value proposition of PEM fuel cells in government markets (2007); Development of the value proposition and opportunity for large fuel cell system application at data centers and wastewater treatment plants (2008); Update of the manufacturing costs of PEM fuel cells for backup power applications (2009).

  13. 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

  14. Failure rate of piping in hydrogen sulphide systems

    International Nuclear Information System (INIS)

    Hare, M.G.

    1993-08-01

    The objective of this study is to provide information about piping failures in hydrogen sulphide service that could be used to establish failures rates for piping in 'sour service'. Information obtained from the open literature, various petrochemical industries and the Bruce Heavy Water Plant (BHWP) was used to quantify the failure analysis data. On the basis of this background information, conclusions from the study and recommendations for measures that could reduce the frequency of failures for piping systems at heavy water plants are presented. In general, BHWP staff should continue carrying out their present integrity and leak detection programmes. The failure rate used in the safety studies for the BHWP appears to be based on the rupture statistics for pipelines carrying sweet natural gas. The failure rate should be based on the rupture rate for sour gas lines, adjusted for the unique conditions at Bruce

  15. Re-examination of the neptunium-hydrogen system

    International Nuclear Information System (INIS)

    Ward, J.W.; Bartscher, W.; Rebizant, J.

    1986-01-01

    New P-C-T studies have been made on the Np + H system, using ultrapure double-electrorefined metal. Measurements were carried out over six orders of magnitude in pressure, from 0.0005 to 70 bar. The solubility of hydrogen was found to be very low. Metal-dihydride plateaus were flat, the two-phase boundary extremely sharp; this occurred at the unusual value H/Np approx. = 2.13. The dihydride lattice expanded upon addition of hydrogen, also in contrast to other trivalent rare-earth and actinide hydrides. A rather narrow cubic/hexagonal two-phase region was found (only on dehydriding), together with an even narrower hexagonal phase region. The effect of the beta-gamma transition at 576 0 C could be seen both in the curvature of the phase boundary and the partial molal enthalpy values. Entropies of formation were found to be nearly constant. The data below 576 0 C can be described by the equation ln P(bar) = 13.297 - 13233/T(K), giving values, adjusted for the reaction 0.93 Np + H 2 = 0.93 NpH/sub 2.13/: ΔH/sub f/(NpH/sub 2.13/) = 118.3 kJ/mol (28.27 kcal/mol), and ΔS/sub f/(NpH/sub 2.13/) = 118.4 J/mol-K (28.3 cal/mol/-K). Integral heats and entropies are calculated for the entire system, and the unusual phase behavior is discussed in terms of the electronic structure

  16. Design optimization of ORC systems for waste heat recovery on board a LNG carrier

    International Nuclear Information System (INIS)

    Soffiato, Marco; Frangopoulos, Christos A.; Manente, Giovanni; Rech, Sergio; Lazzaretto, Andrea

    2015-01-01

    Highlights: • ORC systems are one of the most promising options to recover low temperature heat. • Design of ORC systems on board a LNG carrier is optimized using the Heatsep method. • Simple, regenerative and two-stage, subcritical and supercritical ORCs are considered. • Three engine cooling systems layouts are found to supply heat to the ORCs. • The highest net power output is achieved by the two-stage ORC configuration. - Abstract: Organic Rankine Cycle (ORC) technology may represent an interesting way to exploit the low grade waste heat rejected by the ship power generation plant. This option is investigated here to recover the heat available from three of the four engines of a real electrically driven Liquefied Natural Gas (LNG) carrier. A detailed analysis of the engines operation is first performed to evaluate all thermal streams released by the engines. Heat associated with the jacket water, lubricating oil and charge air cooling of the engines is found to be available for the ORC, while the heat from the exhaust gases is already used to generate low pressure steam for ship internal use. Simple, regenerative and two-stage ORC configurations are compared using six different organic fluids that are selected as the most suitable for this application. The thermal matching that maximizes the net power output of the total system composed by engine cooling circuits and ORC cycle is then found by searching for the optimum heat transfer between thermal streams independently of the structure/number of the heat exchangers. Three layouts of the engine cooling systems are compared. Results show that the maximum net power output (820 kW) achieved by the two-stage ORC configuration almost doubles the simple cycle and regenerative ones (430–580 kW), but structure complexity and reliability issues may give different indications in terms of economic feasibility

  17. Hybrid hydrogen-battery systems for renewable off-grid telecom power

    OpenAIRE

    Scamman, D.; Newborough, M.; Bustamante, H.

    2015-01-01

    Off-grid hybrid systems, based on the integration of hydrogen technologies (electrolysers, hydrogen stores and fuel cells) with battery and wind/solar power technologies, are proposed for satisfying the continuous power demands of telecom remote base stations. A model was developed to investigate the preferred role for electrolytic hydrogen within a hybrid system; the analysis focused on powering a 1 kW telecom load in three locations of distinct wind and solar resource availability. When com...

  18. Technical analysis of photovoltaic/wind systems with hydrogen storage

    Directory of Open Access Journals (Sweden)

    Bakić Vukman V.

    2012-01-01

    Full Text Available The technical analysis of a hybrid wind-photovoltaic energy system with hydrogen gas storage was studied. The market for the distributed power generation based on renewable energy is increasing, particularly for the standalone mini-grid applications. The main design components of PV/Wind hybrid system are the PV panels, the wind turbine and an alkaline electrolyzer with tank. The technical analysis is based on the transient system simulation program TRNSYS 16. The study is realized using the meteorological data for a Typical Metrological Year (TMY for region of Novi Sad, Belgrade cities and Kopaonik national park in Serbia. The purpose of the study is to design a realistic energy system that maximizes the use of renewable energy and minimizes the use of fossil fuels. The reduction in the CO2 emissions is also analyzed in the paper. [Acknowledgment. This paper is the result of the investigations carried out within the scientific project TR33036 supported by the Ministry of Science of the Republic of Serbia.

  19. Sunlight to hydrogen conversion: Design optimization and energy management of concentrated photovoltaic (CPV-Hydrogen) system using micro genetic algorithm

    KAUST Repository

    Burhan, Muhammad

    2016-02-14

    Owing to the intermittent solar irradiance from cloud cover in the diurnal period and unavailability at night time, the practical design of a solar system requires energy backup storage for an uninterrupted supply or for off-grid operation. However, for highly efficient CPV (concentrated photovoltaic) system, the literature is lacking for energy management and optimization algorithm and tool for standalone operation. In this paper, a system with CPV and electrolyser is presented where beam irradiance of sunlight is harnessed to convert the instantaneously generated electricity into useful Hydrogen/Oxygen gas, where they can be stored and re-used for downstream applications such as the fuel cells, etc. The multi-variable design and multi-objective optimization strategies are proposed and presented for a standalone operation of the CPV-Hydrogen system as well as their system performances, particularly electrical rating of CPV based upon the real weather data of Singapore. © 2016 Elsevier Ltd.

  20. Hydrogen as a link between sustainable mobility and transition of the German energy system

    Energy Technology Data Exchange (ETDEWEB)

    Conreder, Alexander [EnBW Energie Baden-Wuerttemberg AG, Karlsruhe (Germany)

    2013-06-01

    Even 15 years ago, the predictions with regard to the market penetration of fuel cell automobiles or of so-called fuel cell heaters were communicated with differing statements. Daimler Benz AG, as it still was back then, had put their faith in the rapid integration of a fuel cell into the vehicle, whereas companies such as Vaillant, Hamburger Gas Consult, Sulzer Hexis or even MTU and Siemens were working on stationary fuel cell systems. The expectations at that time with regard to market and technology development have still not yet been fulfilled. Today, the subject has been given a new lease of life thanks to the public discussions regarding the energy transition and the current framework conditions. Many concepts that have already been under consideration, but which very few have considered realistic in the short-term, now appear at least to have come within reach. As a result of the fluctuations in the generation of renewable energies, Germany needs loads that can be switched and, above all, methods of storing energy. In conjunction with new technologies, such as PEM electrolysis and the pressure which has been put on politics to react and to create the necessary framework conditions, a new momentum has developed with regard to the use of hydrogen. This article analyses to what extent synergies between energy transition and mobility can be expected within the context of hydrogen. With a view to quantity, times and local relationships, quality and price, we have been able to determine that the relevant amounts and dependencies have a positive and relevant magnitude to one another, thus synergies are present. It should be noted that hydrogen will not be the sole solution for the Federal Government when it comes to achieving CO{sub 2} reduction aims. Electrical mobility with approaches for bidirectional charging, new storage technologies and alternative energy carriers, switchable loads as well as the local public transport systems and new mobility concepts will

  1. Optimal Scheduling of a Multi-Carrier Energy Hub Supplemented By Battery Energy Storage Systems

    DEFF Research Database (Denmark)

    Javadi, Mohammad Sadegh; Anvari-Moghaddam, Amjad; Guerrero, Josep M.

    2017-01-01

    This paper introduces a management model for optimal scheduling of a multi-carrier energy hub. In the proposed hub, three types of assets are considered: dispersed generating systems (DGs) such as micro-combined heat and power (mCHP) units, storage devices such as battery-based electrical storage...... systems (ESSs), and heating/cooling devices such as electrical heater, heat-pumps and absorption chillers. The optimal scheduling and management of the examined energy hub assets in line with electrical transactions with distribution network is modeled as a mixed-integer non-linear optimization problem....... In this regard, optimal operating points of DG units as well as ESSs are calculated based on a cost-effective strategy. Degradation cost of ESSs is also taken into consideration for short-term scheduling. Simulation results demonstrate that including well-planned energy storage options together with optimal...

  2. Downlink Radio Resource Management for LTE-Advanced System with Combined MU-MIMO and Carrier Aggregation Features

    DEFF Research Database (Denmark)

    Nguyen, Hung Tuan; Kovacs, Istvan

    2012-01-01

    In this paper we study the performance enhancement of a downlink LTE-Advanced system with a combination of the multi-user MIMO and carrier aggregation transmission techniques. Radio resource management for the systems with the combined features are proposed, and the system performance is evaluate...

  3. Systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies

    Science.gov (United States)

    Fliermans,; Carl, B [Augusta, GA

    2012-08-07

    Some or all of the needs above can be addressed by embodiments of the invention. According to embodiments of the invention, systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies can be implemented. In one embodiment, a method for storing hydrogen can be provided. The method can include providing diatoms comprising diatomaceous earth or diatoms from a predefined culture. In addition, the method can include heating the diatoms in a sealed environment in the presence of at least one of titanium, a transition metal, or a noble metal to provide a porous hydrogen storage medium. Furthermore, the method can include exposing the porous hydrogen storage medium to hydrogen. In addition, the method can include storing at least a portion of the hydrogen in the porous hydrogen storage medium.

  4. Low-cost storage options for solar hydrogen systems for remote area power supply

    International Nuclear Information System (INIS)

    Suhaib Muhammad Ali; John Andrews

    2006-01-01

    Equipment for storing hydrogen gas under pressure typically accounts for a significant proportion of the total capital cost of solar-hydrogen systems for remote area power supply (RAPS). RAPS remain a potential early market for renewable energy - hydrogen systems because of the relatively high costs of conventional energy sources in remote regions. In the present paper the storage requirements of PV-based solar-hydrogen RAPS systems employing PEM electrolysers and fuel cells to meet a range of typical remote area daily and annual demand profiles are investigated using a spread sheet-based simulation model. It is found that as the costs of storage are lowered the requirement for longer-term storage from summer to winter is increased with consequent potential gains in the overall economics of the solar-hydrogen system. In many remote applications, there is ample space for hydrogen storages with relatively large volumes. Hence it may be most cost-effective to store hydrogen at low to medium pressures achievable by using PEM electrolysers directly to generate the hydrogen at the pressures required, without a requirement for separate electrically-driven compressors. The latter add to system costs while requiring significant parasitic electricity consumption. Experimental investigations into a number of low-cost storage options including plastic tanks and low-to-medium pressure metal and composite cylinders are reported. On the basis of these findings, the economics of solar-hydrogen RAPS systems employing large-volume low-cost storage are investigated. (authors)

  5. Improvement of curcuminoid bioaccessibility from turmeric by a nanostructured lipid carrier system.

    Science.gov (United States)

    Park, Sung Jin; Garcia, Coralia V; Shin, Gye Hwa; Kim, Jun Tae

    2018-06-15

    Turmeric contains curcumin and its analogues, which show anticancer and antiinflammatory effects; however, curcuminoids are lipophilic and are poorly absorbed by the human body. Nanostructured lipid carriers for encapsulating whole turmeric powder were successfully produced by ultrasonication, and their physicochemical properties and stability in simulated gastric and intestinal media were evaluated. The turmeric nanostructured lipid carriers (TNLCs) exhibited a round shape, small diameter (282 ± 7.19 nm), adequate zeta potential (-22.75 ± 1.20 mV), and high encapsulation efficiency (93.3 ± 0.01%). The TNLCs were able to protect the encapsulated curcuminoids under acidic gastric conditions, and effectively released 95 ± 2.51% of the curcuminoids in the simulated intestinal medium, demonstrating their suitability for controlled release. The in vitro bioaccessibility of the encapsulated curcuminoids was 75 ± 1.24%, representing more than a fourfold increase compared to that of free turmeric. Therefore, the proposed TNLCs are a promising delivery system for increasing the bioaccessibility of curcuminoids from turmeric. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. Carrier Frequency Offset Estimation and I/Q Imbalance Compensation for OFDM Systems

    Directory of Open Access Journals (Sweden)

    M. Omair Ahmad

    2007-01-01

    Full Text Available Two types of radio-frequency front-end imperfections, that is, carrier frequency offset and the inphase/quadrature (I/Q imbalance are considered for orthogonal frequency division multiplexing (OFDM communication systems. A preamble-assisted carrier frequency estimator is proposed along with an I/Q imbalance compensation scheme. The new frequency estimator reveals the relationship between the inphase and the quadrature components of the received preamble and extracts the frequency offset from the phase shift caused by the frequency offset and the cross-talk interference due to the I/Q imbalance. The proposed frequency estimation algorithm is fast, efficient, and robust to I/Q imbalance. An I/Q imbalance estimation/compensation algorithm is also presented by solving a least-square problem formulated using the same preamble as employed for the frequency offset estimation. The computational complexity of the I/Q estimation scheme is further reduced by using part of the short symbols with a little sacrifice in the estimation accuracy. Computer simulation and comparison with some of the existing algorithms are conducted, showing the effectiveness of the proposed method.

  7. A Hydrogen Ignition Mechanism for Explosions in Nuclear Facility Piping Systems

    Energy Technology Data Exchange (ETDEWEB)

    Leishear, Robert A.

    2013-09-18

    Hydrogen explosions may occur simultaneously with water hammer accidents in nuclear facilities, and a theoretical mechanism to relate water hammer to hydrogen deflagrations and explosions is presented herein. Hydrogen and oxygen generation due to the radiolysis of water is a recognized hazard in pipe systems used in the nuclear industry, where the accumulation of hydrogen and oxygen at high points in the pipe system is expected, and explosive conditions may occur. Pipe ruptures in nuclear reactor cooling systems were attributed to hydrogen explosions inside pipelines, i.e., Hamaoka, Nuclear Power Station in Japan, and Brunsbuettel in Germany. Prior to these accidents, an ignition source for hydrogen was not clearly demonstrated, but these accidents demonstrated that a mechanism was, in fact, available to initiate combustion and explosion. A new theory to identify an ignition source and explosion cause is presented here, and further research is recommended to fully understand this explosion mechanism.

  8. Cost estimation of hydrogen and DME produced by nuclear heat utilization system. Joint research

    International Nuclear Information System (INIS)

    Shiina, Yasuaki; Nishihara, Tetsuo

    2003-09-01

    Research of hydrogen energy has been performed in order to spread use of the hydrogen energy in 2020 or 2030. It will take, however, many years for the hydrogen energy to be used very easily like gasoline, diesel oil and city gas in all of countries. During the periods, low CO 2 release liquid fuels would be used together with hydrogen. Recently, di-methyl-either (DME) has been noticed as one of the substitute liquid fuels of petroleum. Such liquid fuels can be produced from the mixed gas such as hydrogen and carbon oxide which are produced by steam reforming hydrogen generation system by the use of nuclear heat. Therefore, the system would be one of the candidates of future system of nuclear heat utilization. In the present study, we focused on the production of hydrogen and DME. Economic evaluation was estimated for hydrogen and DME production in commercial and nuclear heat utilization plant. At first, heat and mass balance of each process in commercial plant of hydrogen production was estimated and commercial prices of each process were derived. Then, price was estimated when nuclear heat was used instead of required heat of commercial plant. Results showed that the production prices produced by nuclear heat were cheaper by 10% for hydrogen and 3% for DME. With the consideration of reduction effect of CO 2 release, utilization of nuclear heat would be more effective. (author)

  9. Possibility of hydrogen supply by shared residential fuel cell systems for fuel cell vehicles

    Directory of Open Access Journals (Sweden)

    Ono Yusuke

    2017-01-01

    Full Text Available Residential polymer electrolyte fuel cells cogeneration systems (residential PEFC systems produce hydrogen from city gas by internal gas-reformer, and generate electricity, the hot water at the same time. From the viewpoint of the operation, it is known that residential PEFC systems do not continuously work but stop for long time, because the systems generate enough hot water for short operation time. In other words, currently residential PEFC systems are dominated by the amount of hot water demand. This study focuses on the idle time of residential PEFC systems. Since their gas-reformers are free, the systems have potential to produce hydrogen during the partial load operations. The authors expect that residential PEFC systems can take a role to supply hydrogen for fuel cell vehicles (FCVs before hydrogen fueling stations are distributed enough. From this perspective, the objective of this study is to evaluate the hydrogen production potential of residential PEFC systems. A residential PEFC system was modeled by the mixed integer linear programming to optimize the operation including hydrogen supply for FCV. The objective function represents annual system cost to be minimized with the constraints of energy balance. It should be noted that the partial load characteristics of the gas-reformer and the fuel cell stack are taken into account to derive the optimal operation. The model was employed to estimate the possible amount of hydrogen supply by a residential PEFC system. The results indicated that the system could satisfy at least hydrogen demand for transportation of 8000 km which is as far as the average annual mileage of a passenger car in Japan. Furthermore, hydrogen production by sharing a residential PEFC system with two households is more effective to reduce primary energy consumption with hydrogen supply for FCV than the case of introducing PEFC in each household.

  10. Energy pathway analysis - a hydrogen fuel cycle framework for system studies

    International Nuclear Information System (INIS)

    Badin, J.S.; Tagore, S.

    1997-01-01

    An analytical framework has been developed that can be used to estimate a range of life-cycle costs and impacts that result from the incremental production, storage, transport, and use of different fuels or energy carriers, such as hydrogen, electricity, natural gas, and gasoline. This information is used in a comparative analysis of energy pathways. The pathways provide the U.S. Department of Energy (DOE) with an indication of near-, mid-, and long-term technologies that have the greatest potential for advancement and can meet the cost goals. The methodology and conceptual issues are discussed. Also presented are results for selected pathways from the E3 (Energy, Economics, Emissions) Pathway Analysis Model. This model will be expanded to consider networks of pathways and to be compatible with a linear programming optimization processor. Scenarios and sets of constraints (energy demands, sources, emissions) will be defined so the effects on energy transformation activities included in the solution and on the total optimized system cost can be investigated. This evaluation will be used as a guide to eliminate technically feasible pathways if they are not cost effective or do not meet the threshold requirements for the market acceptance. (Author)

  11. Biocatalytic methanation of hydrogen and carbon dioxide in an anaerobic three-phase system.

    Science.gov (United States)

    Burkhardt, M; Koschack, T; Busch, G

    2015-02-01

    A new type of anaerobic trickle-bed reactor was used for biocatalytic methanation of hydrogen and carbon dioxide under mesophilic temperatures and ambient pressure in a continuous process. The conversion of gaseous substrates through immobilized hydrogenotrophic methanogenic archaea in a biofilm is a unique feature of this type of reactor. Due to the formation of a three-phase system on the carrier surface and operation as a plug flow reactor without gas recirculation, a complete reaction could be observed. With a methane concentration higher than c(CH4) = 98%, the product gas exhibits a very high quality. A specific methane production of P(CH4) = 1.49 Nm(3)/(m(3)(SV) d) was achieved at a hydraulic loading rate of LR(H2) = 6.0 Nm(3)/(m(3)(SV) d). The relation between trickle flow through the reactor and productivity could be shown. An application for methane enrichment in combination with biogas facilities as a source of carbon dioxide has also been positively proven. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Electronic specific heats in metal--hydrogen systems

    International Nuclear Information System (INIS)

    Flotow, H.E.

    1979-01-01

    The electronic specific heats of metals and metal--hydrogen systems can in many cases be evaluated from the measured specific heats at constant pressure, C/sub p/, in the temperature range 1 to 10 K. For the simplest case, C/sub p/ = γT + βT 3 , where γT represents the specific heat contribution associated with the conduction electrons, and βT 3 represents lattice specific heat contribution. The electronic specific heat coefficient, γ, is important because it is proportional to electron density of states at the Fermi surface. A short description of a low temperature calorimetric cryostat employing a 3 He/ 4 He dilution refrigeration is given. Various considerations and complications encountered in the evaluation of γ from specific heat data are discussed. Finally, the experimental values of γ for the V--Cr--H system and for the Lu--H system are summarized and the variations of γ as function of alloy composition are discussed

  13. Development of a simple bio-hydrogen production system through dark fermentation by using unique microflora

    Energy Technology Data Exchange (ETDEWEB)

    Ohnishi, Akihiro; Bando, Yukiko; Fujimoto, Naoshi; Suzuki, Masaharu [Department of Fermentation Science, Faculty of Applied Bio-Science, Tokyo University of Agriculture, 1-1 Sakuragaoka 1-chome, Setagaya-ku, Tokyo 156-8502 (Japan)

    2010-08-15

    In order to ensure efficient functioning of hydrogen fermentation systems that use Clostridium as the dominant hydrogen producer, energy-intensive process such as heat pretreatment of inoculum and/or substrate, continuous injection, and control of anaerobic conditions are required. Here, we describe a simple hydrogen fermentation system designed using microflora from leaf-litter cattle-waste compost. Hydrogen and volatile fatty acid production was measured at various hydraulic retention times, and bacterial genera were determined by PCR amplification and sequencing. Although hydrogen fermentation yield was approximately one-third of values reported in previous studies, this system requires no additional treatment and thus may be advantageous in terms of cost and operational control. Interestingly, Clostridium was absent from this system. Instead, Megasphaera elsdenii was the dominant hydrogen-producing bacterium, and lactic acid-producing bacteria (LAB) were prevalent. This study is the first to characterize M. elsdenii as a useful hydrogen producer in hydrogen fermentation systems. These results demonstrate that pretreatment is not necessary for stable hydrogen fermentation using food waste. (author)

  14. Applications of some microscopic, diffraction and absorption techniques to the study of metal--hydrogen systems

    International Nuclear Information System (INIS)

    Pick, M.A.

    1979-01-01

    Several experimental techniques were reviewed which are used to investigate metal hydrogen systems. The first technique is metallography and optical microscopy. This is a very old technique which was found to be very powerful in the case of metal hydrogen systems. A few examples of such work are shown and the results are discussed

  15. Long-Term Cycling of the Magnesium Hydrogen System

    DEFF Research Database (Denmark)

    Pedersen, Allan Schrøder; Kjøller, John; Larsen, Bent

    1984-01-01

    Magnesium powder with a grain size of approximately 50γm was hydrogenated for 30 min and dehydrogenated the same time at 390°C, 515 times. A moderate loss in hydrogen storage capacity was observed and was ascribed to a measured decrease in reaction kinetics as the cycle number increased. The time...

  16. Multi-criteria analysis on how to select solar radiation hydrogen production system

    Energy Technology Data Exchange (ETDEWEB)

    Badea, G.; Naghiu, G. S., E-mail: naghiu.george@gmail.com; Felseghi, R.-A.; Giurca, I., E-mail: giurca-ioan@yahoo.com [Technical University of Cluj-Napoca, Faculty of Building Services Engineering, Boulevard December 21, no. 128-130, Cluj-Napoca, 400604 (Romania); Răboacă, S. [National R& D Institute for Cryogenic and Isotopic Technologies, str. Uzinei, no. 4, Rm. Vălcea, 240050 (Romania); Aşchilean, I. [SC ACI Cluj SA, Avenue Dorobanţilor, no. 70, Cluj-Napoca, 400609 (Romania)

    2015-12-23

    The purpose of this article is to present a method of selecting hydrogen-production systems using the electric power obtained in photovoltaic systems, and as a selecting method, we suggest the use of the Advanced Multi-Criteria Analysis based on the FRISCO formula. According to the case study on how to select the solar radiation hydrogen production system, the most convenient alternative is the alternative A4, namely the technical solution involving a hydrogen production system based on the electrolysis of water vapor obtained with concentrated solar thermal systems and electrical power obtained using concentrating photovoltaic systems.

  17. Two step novel hydrogen system using additives to enhance hydrogen release from the hydrolysis of alane and activated aluminum

    Science.gov (United States)

    Zidan, Ragaiy; Teprovich, Joseph A.; Motyka, Theodore

    2015-12-01

    A system for the generation of hydrogen for use in portable power systems is set forth utilizing a two-step process that involves the thermal decomposition of AlH.sub.3 (10 wt % H.sub.2) followed by the hydrolysis of the activated aluminum (Al*) byproduct to release additional H.sub.2. Additionally, a process in which water is added directly without prior history to the AlH.sub.3:PA composite is also disclosed.

  18. Hydrogen systems : a Canadian strategy for greenhouse gas reduction and economic growth

    International Nuclear Information System (INIS)

    2005-01-01

    Rising concerns about the depletion of fossil fuels and climate change have led to the search for new energy sources. This paper outlines the mission of the Canadian Hydrogen Association, which is to build on Canada's energy resource base and expertise in hydrogen technologies in order to deploy sustainable hydrogen energy systems. Basic strategies needed to develop hydrogen systems in Canada were outlined, with specific reference to the establishment of low cost energy sources with low life-cycle emissions. The current hydrogen infrastructure produces marginal life-cycle emissions benefits, particularly when compared with improvements in technologies expected in the next 10 years. It was noted that regional development of hydrogen systems was likely to be an effective strategy, due to high transportation costs. Several potential locations were discussed for the development of a hydrogen energy infrastructure. Opportunities arising from hydrogen vehicle penetration of consumer markets and the broad commercialization of fuel cells were examined. Feasible transition strategies were reviewed, to be built in the near term around pathways such as hydrogen internal combustion engines and fuel cell vehicles designed for high-value niche applications. Strategies addressing the preparation of the market to express the value proposition for hydrogen were discussed, with reference to the fact that the existing energy market places no value on environmental factors. Several recommendations were made to conclude the discussion, and included: the necessity of government action to establish national goals; the creation of a stakeholder base for hydrogen systems; a government and industry partnership towards the development of a near-term commercialization plan; and the establishment of a long-term direction for the development of hydrogen systems in terms of advancing technology and public education. refs., tabs., figs

  19. Sunlight to hydrogen conversion: Design optimization and energy management of concentrated photovoltaic (CPV-Hydrogen) system using micro genetic algorithm

    International Nuclear Information System (INIS)

    Burhan, Muhammad; Chua, Kian Jon Ernest; Ng, Kim Choon

    2016-01-01

    Owing to the intermittent solar irradiance from cloud cover in the diurnal period and unavailability at night time, the practical design of a solar system requires energy backup storage for an uninterrupted supply or for off-grid operation. However, for highly efficient CPV (concentrated photovoltaic) system, the literature is lacking for energy management and optimization algorithm and tool for standalone operation. In this paper, a system with CPV and electrolyser is presented where beam irradiance of sunlight is harnessed to convert the instantaneously generated electricity into useful Hydrogen/Oxygen gas, where they can be stored and re-used for downstream applications such as the fuel cells, etc. The multi-variable design and multi-objective optimization strategies are proposed and presented for a standalone operation of the CPV-Hydrogen system as well as their system performances, particularly electrical rating of CPV based upon the real weather data of Singapore. - Highlights: • Design modelling and energy management strategy is proposed for CPV-Hydrogen system. • Micro GA does multi-variable and multi-objective optimization for standalone operation. • Design is verified and analysed for minimum cost, zero PSFT and optimal storage. • Performance of each component is presented for different real weather data conditions. • Proposed design approach is applicable in all regions with low and high DNI.

  20. Protein S-sulfhydration by hydrogen sulfide in cardiovascular system.

    Science.gov (United States)

    Meng, Guoliang; Zhao, Shuang; Xie, Liping; Han, Yi; Ji, Yong

    2018-04-01

    Hydrogen sulfide (H 2 S), independently of any specific transporters, has a number of biological effects on the cardiovascular system. However, until now, the detailed mechanism of H 2 S was not clear. Recently, a novel post-translational modification induced by H 2 S, named S-sulfhydration, has been proposed. S-sulfhydration is the chemical modification of specific cysteine residues of target proteins by H 2 S. There are several methods for detecting S-sulfhydration, such as the modified biotin switch assay, maleimide assay with fluorescent thiol modifying regents, tag-switch method and mass spectrometry. H 2 S induces S-sulfhydration on enzymes or receptors (such as p66Shc, phospholamban, protein tyrosine phosphatase 1B, mitogen-activated extracellular signal-regulated kinase 1 and ATP synthase subunit α), transcription factors (such as specific protein-1, kelch-like ECH-associating protein 1, NF-κB and interferon regulatory factor-1), and ion channels (such as voltage-activated Ca 2+ channels, transient receptor potential channels and ATP-sensitive K + channels) in the cardiovascular system. Although significant progress has been achieved in delineating the role of protein S-sulfhydration by H 2 S in the cardiovascular system, more proteins with detailed cysteine sites of S-sulfhydration as well as physiological function need to be investigated in further studies. This review mainly summarizes the role and possible mechanism of S-sulfhydration in the cardiovascular system. The S-sulfhydrated proteins may be potential novel targets for therapeutic intervention and drug design in the cardiovascular system, which may accelerate the development and application of H 2 S-related drugs in the future. This article is part of a themed section on Spotlight on Small Molecules in Cardiovascular Diseases. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v175.8/issuetoc. © 2017 The British Pharmacological Society.

  1. Study on system layout and component design in the HTTR hydrogen production system. Contract research

    International Nuclear Information System (INIS)

    Nishihara, Tetsuo; Shimizu, Akira; Uchida, Shoji

    2003-01-01

    The global warming becomes a significant issue in the world so that it needs to reduce the CO 2 emission. It is expected that hydrogen is in place of the fossil fuels such as coal and oil, and plays the important role to resolve the global warming. There are several hydrogen making processes such as water electrolysis and steam reforming of hydrocarbon. Steam reforming of hydrocarbon is a major hydrogen making process because of economy in industry. It utilizes the fossil fuels as process heat for chemical reaction and results in a large CO 2 emission. New steam reforming system without fossil fuel can contribute to resolve the global warming. High temperature gas-cooled reactor (HTGR) has a unique feature to be able to supply a hot helium gas whose temperature is approximately 950degC at the reactor outlet. This makes HTGR possible to utilize for not only power generation but also process heat utilization. JAERI constructed the high temperature engineering test reactor (HTTR) that is a sort of HTGR in Oarai establishment and starts operation. Nuclear heat utilization is one of the R and D items of the HTTR. The steam reforming system coupling to the HTTR for hydrogen production has been designed. This report represents the system layout and design specification of key components in HTTR steam reforming system. (author)

  2. System-of-Systems Framework for the Future Hydrogen-Based Transportation Economy: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Duffy, M.; Sandor, D.

    2008-06-01

    From a supply chain view, this paper traces the flow of transportation fuels through required systems and addresses the current petroleum-based economy, DOE's vision for a future hydrogen-based transportation economy, and the challenges of a massive market and infrastructure transformation.

  3. Study on system layout and component design in the HTTR hydrogen production system. Contract research

    Energy Technology Data Exchange (ETDEWEB)

    Nishihara, Tetsuo; Shimizu, Akira [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment; Tanihira, Masanori [Mitsubishi Heavy Industries Ltd., Tokyo (Japan); Uchida, Shoji [Advanced Reactor Technology Co., Ltd., Tokyo (Japan)

    2003-01-01

    The global warming becomes a significant issue in the world so that it needs to reduce the CO{sub 2} emission. It is expected that hydrogen is in place of the fossil fuels such as coal and oil, and plays the important role to resolve the global warming. There are several hydrogen making processes such as water electrolysis and steam reforming of hydrocarbon. Steam reforming of hydrocarbon is a major hydrogen making process because of economy in industry. It utilizes the fossil fuels as process heat for chemical reaction and results in a large CO{sub 2} emission. New steam reforming system without fossil fuel can contribute to resolve the global warming. High temperature gas-cooled reactor (HTGR) has a unique feature to be able to supply a hot helium gas whose temperature is approximately 950degC at the reactor outlet. This makes HTGR possible to utilize for not only power generation but also process heat utilization. JAERI constructed the high temperature engineering test reactor (HTTR) that is a sort of HTGR in Oarai establishment and starts operation. Nuclear heat utilization is one of the R and D items of the HTTR. The steam reforming system coupling to the HTTR for hydrogen production has been designed. This report represents the system layout and design specification of key components in HTTR steam reforming system. (author)

  4. Development of a reduction-sensitive diselenide-conjugated oligoethylenimine nanoparticulate system as a gene carrier

    Directory of Open Access Journals (Sweden)

    Cheng G

    2012-07-01

    Full Text Available Gang Cheng,1,2 Yiyan He,1 Li Xie,1 Yu Nie,1 Bin He,1 Zhirong Zhang,2 Zhongwei Gu11National Engineering Research Center for Biomaterials, 2Key Laboratory of Drug Targeting and Drug Delivery Systems, West China School of Pharmacy, Sichuan University, Chengdu, Sichuan, People's Republic of ChinaBackground: The reduction-sensitive cationic polymer is a promising nonviral carrier for gene delivery. Until now, disulfide bonds have been the only golden standard for its design. The aim of this research was to develop a novel reduction-responsive cationic polymer as a gene carrier.Methods: Polycationic carriers were synthesized by addition of branched oligoethylenimine 800 Da (OEI800 via an active ester containing diselenide bonds. Disulfide bonds cross-linked with OEI800-SSx and monoselenide bonds linked with OEI800-Sex were synthesized and compared. Their molecular weights and degradation properties were determined using gel permeation chromatography. Changes in particle size, morphology, and DNA binding were investigated by dynamic light scattering, transmission electron microscopy, and electrophoresis assay in a reduction environment. Cytotoxicity and transfection in vitro were evaluated in a murine melanoma cell line (B16F10 and a human cervical epithelial carcinoma cell line (HeLa, while intracellular degradation and dissociation with DNA were studied by confocal laser scanning microscopy with FITC-labeled OEI800 derivatives and Cy5-labeled DNA.Results: Diselenide-conjugated OEI800 (OEI800-Se Sex polymer carriers of high molecular weight were successfully synthesized. After compacting with DNA, the OEI800-SeSex polymers formed nanoparticles with an average size of 140 nm at an adequate C/P ratio. OEI800-Se Sex showed reduction-responsive degradation properties similar to those of the OEI800-SSx via gel permeation chromatography, dynamic light scattering, and transmission electron microscopy. OEI800-SeSex showed much lower cytotoxicity than PEI25k

  5. A DHT Key-Value Storage System with Carrier Grade Performance

    Science.gov (United States)

    Shi, Guangyu; Chen, Jian; Gong, Hao; Fan, Lingyuan; Xue, Haiqiang; Lu, Qingming; Liang, Liang

    The Peer-to-Peer (P2P) technology being widely adopted in today’s both academic research and practical service providing, has many potential advantages and achieves a great success in Information Technology scope. Recently some researchers have proposed that P2P inspired architecture also might be one choice for the telecom network evolution. Most of such works adopted structured P2P (DHT) as the basic solutions, but they seldom discussed how to eliminate the huge gap between the telecom underlay performance requirement and the performance of existed DHT which mainly originated from the Internet applications. This paper presents the design and implementation of SandStone, a DHT based key-value storage system with carrier grade performance, such as good scalability, strong consistency and high reliability, which could be deployed as the cornerstone in such new P2P inspired networking architectures.

  6. Comparative feasibility study on retrofitting ballast water treatment system for a bulk carrier.

    Science.gov (United States)

    Jee, Jaehoon; Lee, Sangick

    2017-06-30

    Use of ballast water in ships causes harmful effects on marine environment accompanied by economic loss and negative impact on ecosystem and human health. To solve these problems, the international convention on ballast water management will take into force in September 2017. In this study, a comprehensive feasibility of retrofitting the ballast water treatment system for an ocean-going bulk carrier was conducted. The technologies involved, installation and operational aspects of direct flow and side stream electrolysis, UV, and ozone type BWTS are described in detail. The principal concept of each BWTS is explained and probable arrangements of retrofitting in engine room are suggested. The cost analysis is carried out for retrofitting 4 types of BWTS onboard the target ship by examining each processes of installation and operation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. The Italian hydrogen programme

    International Nuclear Information System (INIS)

    Raffaele Vellone

    2001-01-01

    Hydrogen could become an important option in the new millennium. It provides the potential for a sustainable energy system as it can be used to meet most energy needs without harming the environment. In fact, hydrogen has the potential for contributing to the reduction of climate-changing emissions and other air pollutants as it exhibits clean combustion with no carbon or sulphur oxide emissions and very low nitrogen oxide emissions. Furthermore, it is capable of direct conversion to electricity in systems such as fuel cells without generating pollution. However, widespread use of hydrogen is not feasible today because of economic and technological barriers. In Italy, there is an ongoing national programme to facilitate the introduction of hydrogen as an energy carrier. This programme aims to promote, in an organic frame, a series of actions regarding the whole hydrogen cycle. It foresees the development of technologies in the areas of production, storage, transport and utilisation. Research addresses the development of technologies for separation and sequestration of CO 2 , The programme is shared by public organisations (research institutions and universities) and national industry (oil companies, electric and gas utilities and research institutions). Hydrogen can be used as a fuel, with significant advantages, both for electric energy generation/ co-generation (thermo-dynamic cycles and fuel cells) and transportation (internal combustion engine and fuel cells). One focus of research will be the development of fuel cell technologies. Fuel cells possess all necessary characteristics to be a key technology in a future economy based on hydrogen. During the initial phase of the project, hydrogen will be derived from fossil sources (natural gas), and in the second phase it will be generated from renewable electricity or nuclear energy. The presentation will provide a review of the hydrogen programme and highlight future goals. (author)

  8. H2 at Scale: Benefitting our Future Energy System - Update for the Hydrogen Technical Advisory Committee

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, Mark

    2016-12-06

    Hydrogen is a flexible, clean energy carrying intermediate that enables aggressive market penetration of renewables while deeply decarbonizing our energy system. H2 at Scale is a concept that supports the electricity grid by utilizing energy without other demands at any given time and also supports transportation and industry by providing low-priced hydrogen to them. This presentation is an update to the Hydrogen Technical Advisory Committee (HTAC).

  9. Modeling and control design of hydrogen production process for an active hydrogen/wind hybrid power system

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Tao; Francois, Bruno [L2EP, Ecole Centrale de Lille, Cite Scientifique, BP48, 59651, Villeneuve d' Ascq (France)

    2009-01-15

    This paper gives a control oriented modeling of an electrolyzer, as well as the ancillary system for the hydrogen production process. A Causal Ordering Graph of all necessary equations has been used to illustrate the global scheme for an easy understanding. The model is capable of characterizing the relations among the different physical quantities and can be used to determine the control system ensuring efficient and reliable operation of the electrolyzer. The proposed control method can manage the power flow and the hydrogen flow. The simulation results have highlighted the variation domains and the relations among the different physical quantities. The model has also been experimentally tested in real time with a Hardware-In-the-Loop Simulation before being integrated in the test bench of the active wind energy conversion system. (author)

  10. New Modeling and Simulation Platform for Communications Systems:(I Double Sideband Suppressed Carrier AM Modulator DSB-SC

    Directory of Open Access Journals (Sweden)

    H. A. Ahmed

    2012-08-01

    Full Text Available The main goal of this paper is to introduce a new platform for the implementation and simulation of communication systems. SCILAB/SCICOS is an open source software for conducting communication system related experiments, aiming to provide an experimentation platform for research on communication theories. Double Sideband Suppressed Carrier (DSB-SC Modulator is modeled and simulated using this platform.

  11. Assessment of MHR-based hydrogen energy systems

    International Nuclear Information System (INIS)

    Richards, Matthew; Shenoy, Arkal; Schultz, Kenneth; Brown, Lloyd; Besenbruch, Gottfried; Handa, Norihiko; Das, Jadu

    2004-01-01

    Process heat from a high-temperature nuclear reactor can be used to drive a set of chemical reactions, with the net result of splitting water into hydrogen and oxygen. For example, process heat at temperatures in the range 850degC to 950degC can drive the sulfur-iodine (SI) thermochemical process to produce hydrogen with high efficiency. The SI process produces highly pure hydrogen and oxygen, with formation, decomposition, regeneration, and recycle of the intermediate chemical reagents and low-temperature heat as the only waste product. Electricity can also be used directly to split water, using conventional, low-temperature electrolysis (LTE). Hydrogen can also be produced with hybrid processes that use both process heat and electricity to generate hydrogen. An example of a hybrid process is high-temperature electrolysis (HTE), in which process heat is used to generate steam, which is then supplied to an electrolyzer to generate hydrogen. This process is of interest because the efficiency of electrolysis increases with temperature. Because of its high-temperature capability, advanced of development relative to other high-temperature reactor concepts, and passive-safety features, the Modular Helium Reactor (MHR) is well suited for producing hydrogen using nuclear energy. In this paper we investigate concepts for coupling the MHR to the SI process, LTE, and HTE. These concepts are referred to as the H2-MHR. (author)

  12. Optimization of stand-alone photovoltaic systems with hydrogen storage for total energy self-sufficiency

    Energy Technology Data Exchange (ETDEWEB)

    Lund, P D [Helsinki Univ. of Technology, Espoo (Finland). Dept. of Technical Physics

    1991-01-01

    A new method for optimization of stand-alone photovoltaic-hydrogen energy systems is presented. The methodology gives the optimum values for the solar array and hydrogen storage size for any given system configuration and geographical site. Sensitivity analyses have been performed to study the effect of subsystem efficiencies on the total system performance and sizing, and also to identify possibilities for further improvements. Optimum system configurations have also been derived. The results indicate that a solar-hydrogen energy system is a very promising potential alternative for low power applications requiring a total electricity self-sufficiency. (Author).

  13. Parameter study on Japanese proposal of ITER hydrogen isotope separation system

    International Nuclear Information System (INIS)

    Yoshida, Hiroshi; Enoeda, Mikio; Tanaka, Shigeru; Ohokawa, Yoshinao; Ohara, Atsushi; Nagakura, Masaaki; Naito, Taisei; Nagashima, Kazuhiro.

    1991-01-01

    As part of Japanese design contribution in the ITER activity, conceptual design of an entire ITER tritium system and their safety analysis have been carried out through the three-year period since 1988. The tritium system includes the following subsystems; - Fuelling (gas puffing and pellet injection) subsystem, - Torus vacuum pumping subsystem, - Plasma exhaust gas purification subsystem, - Hydrogen isotope separation subsystem, - NBI gas processing subsystem, - Blanket tritium recovery subsystem, - Tritiated water processing subsystem, - Tritium safety subsystem. Hydrogen isotope separation system is a key subsystem in the ITER tritium system because it is connected to all above subsystems. This report describes an analytical study on the Japanese concept of hydrogen isotope separation system. (author)

  14. Safety assessment of envisaged systems for automotive hydrogen supply and utilization

    Energy Technology Data Exchange (ETDEWEB)

    Landucci, Gabriele [Dipartimento di Ingegneria Chimica, Chimica Industriale e Scienza dei Materiali, Universita di Pisa, via Diotisalvi n.2, 56126 Pisa (Italy); Tugnoli, Alessandro; Cozzani, Valerio [Dipartimento di Ingegneria Chimica, Mineraria e delle Tecnologie Ambientali, Alma Mater Studiorum - Universita di Bologna, via Terracini n.28, 40131 Bologna (Italy)

    2010-02-15

    A novel consequence-based approach was applied to the inherent safety assessment of the envisaged hydrogen production, distribution and utilization systems, in the perspective of the widespread hydrogen utilization as a vehicle fuel. Alternative scenarios were assessed for the hydrogen system chain from large scale production to final utilization. Hydrogen transportation and delivery was included in the analysis. The inherent safety fingerprint of each system was quantified by a set of Key Performance Indicators (KPIs). Rules for KPIs aggregation were considered for the overall assessment of the system chains. The final utilization stage resulted by large the more important for the overall expected safety performance of the system. Thus, comparison was carried out with technologies proposed for the use of other low emission fuels, as LPG and natural gas. The hazards of compressed hydrogen-fueled vehicles resulted comparable, while reference innovative hydrogen technologies evidenced a potentially higher safety performance. Thus, switching to the inherently safer technologies currently under development may play an important role in the safety enhancement of hydrogen vehicles, resulting in a relevant improvement of the overall safety performance of the entire hydrogen system. (author)

  15. Availability of steam generator against thermal disturbance of hydrogen production system coupled to HTGR

    International Nuclear Information System (INIS)

    Shibata, Taiju; Nishihara, Tetsuo; Hada, Kazuhiko; Shiozawa, Shusaku

    1996-01-01

    One of the safety issues to couple a hydrogen production system to an HTGR is how the reactor coolability can be maintained against anticipated abnormal reduction of heat removal (thermal disturbance) of the hydrogen production system. Since such a thermal disturbance is thought to frequently occur, it is desired against the thermal disturbance to keep reactor coolability by means other than reactor scram. Also, it is thought that the development of a passive cooling system for such a thermal disturbance will be necessary from a public acceptance point of view in a future HTGR-hydrogen production system. We propose a SG as the passive cooling system which can keep the reactor coolability during a thermal disturbance of a hydrogen production system. This paper describes the proposed steam generator (SG) for the HTGR-hydrogen production system and a result of transient thermal-hydraulic analysis of the total system, showing availability of the SG against a thermal disturbance of the hydrogen production system in case of the HTTR-steam reforming hydrogen production system. (author)

  16. Biomimetic hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Krassen, Henning

    2009-05-15

    Hydrogenases catalyze the reduction of protons to molecular hydrogen with outstanding efficiency. An electrode surface which is covered with active hydrogenase molecules becomes a promising alternative to platinum for electrochemical hydrogen production. To immobilize the hydrogenase on the electrode, the gold surface was modified by heterobifunctional molecules. A thiol headgroup on one side allowed the binding to the gold surface and the formation of a self-assembled monolayer. The other side of the molecules provided a surface with a high affinity for the hydrogenase CrHydA1 from Chlamydomonas reinhardtii. With methylviologen as a soluble energy carrier, electrons were transferred from carboxy-terminated electrodes to CrHydA1 and conducted to the active site (H-cluster), where they reduce protons to molecular hydrogen. A combined approach of surface-enhanced infrared absorption spectroscopy, gas chromatography, and surface plasmon resonance allowed quantifying the hydrogen production on a molecular level. Hydrogen was produced with a rate of 85 mol H{sub 2} min{sup -1} mol{sup -1}. On a 1'- benzyl-4,4'-bipyridinum (BBP)-terminated surface, the electrons were mediated by the monolayer and no soluble electron carrier was necessary to achieve a comparable hydrogen production rate (approximately 50% of the former system). The hydrogen evolution potential was determined to be -335 mV for the BBP-bound hydrogenase and -290 mV for the hydrogenase which was immobilized on a carboxy-terminated mercaptopropionic acid SAM. Therefore, both systems significantly reduce the hydrogen production overpotential and allow electrochemical hydrogen production at an energy level which is close to the commercially applied platinum electrodes (hydrogen evolution potential of -270 mV). In order to couple hydrogen production and photosynthesis, photosystem I (PS1) from Synechocystis PCC 6803 and membrane-bound hydrogenase (MBH) from Ralstonia eutropha were bound to each other

  17. Hydrogen generation systems utilizing sodium silicide and sodium silica gel materials

    Science.gov (United States)

    Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael

    2015-07-14

    Systems, devices, and methods combine reactant materials and aqueous solutions to generate hydrogen. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Multiple inlets of varied placement geometries deliver aqueous solution to the reaction. The reactant materials and aqueous solution are churned to control the state of the reaction. The aqueous solution can be recycled and returned to the reaction. One system operates over a range of temperatures and pressures and includes a hydrogen separator, a heat removal mechanism, and state of reaction control devices. The systems, devices, and methods of generating hydrogen provide thermally stable solids, near-instant reaction with the aqueous solutions, and a non-toxic liquid by-product.

  18. Highly efficient hydrogen storage system based on ammonium bicarbonate/formate redox equilibrium over palladium nanocatalysts.

    Science.gov (United States)

    Su, Ji; Yang, Lisha; Lu, Mi; Lin, Hongfei

    2015-03-01

    A highly efficient, reversible hydrogen storage-evolution process has been developed based on the ammonium bicarbonate/formate redox equilibrium over the same carbon-supported palladium nanocatalyst. This heterogeneously catalyzed hydrogen storage system is comparable to the counterpart homogeneous systems and has shown fast reaction kinetics of both the hydrogenation of ammonium bicarbonate and the dehydrogenation of ammonium formate under mild operating conditions. By adjusting temperature and pressure, the extent of hydrogen storage and evolution can be well controlled in the same catalytic system. Moreover, the hydrogen storage system based on aqueous-phase ammonium formate is advantageous owing to its high volumetric energy density. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. A rationale plan for conversion of Malaysia for solar hydrogen energy system and its benefits

    International Nuclear Information System (INIS)

    Ludin, N.A.; Kamaruddin, W.N.; Kamaruzzaman Sopian; Verizoglu, T.N.

    2006-01-01

    It expected that early in the next century, Malaysia production of petroleum and natural gas will peak, and thereafter production will decline. In parallel with this production decline, Malaysia income from fossil fuels will start to decline, which would hurt the economy. One possible solution for Malaysia is the of Malaysia is the conversion to a hydrogen energy system. In order to move towards a sustainable hydrogen energy system, a future strategy must be outlined, followed, and continually revised. This paper will underline the available hydrogen technologies for production, storage, delivery, conversion, transportation and end use energy applications for the implementation of hydrogen energy system. Therefore, this paper will also emphasis the key success factors to drive the rationale plan for conversion to hydrogen energy system for Malaysia

  20. HYDROGEN PRODUCTION AND DELIVERY INFRASTRUCTURE AS A COMPLEX ADAPTIVE SYSTEM

    Energy Technology Data Exchange (ETDEWEB)

    Tolley, George S

    2010-06-29

    An agent-based model of the transition to a hydrogen transportation economy explores influences on adoption of hydrogen vehicles and fueling infrastructure. Attention is given to whether significant penetration occurs and, if so, to the length of time required for it to occur. Estimates are provided of sensitivity to numerical values of model parameters and to effects of alternative market and policy scenarios. The model is applied to the Los Angeles metropolitan area In the benchmark simulation, the prices of hydrogen and non-hydrogen vehicles are comparable. Due to fuel efficiency, hydrogen vehicles have a fuel savings advantage of 9.8 cents per mile over non-hydrogen vehicles. Hydrogen vehicles account for 60% of new vehicle sales in 20 years from the initial entry of hydrogen vehicles into show rooms, going on to 86% in 40 years and reaching still higher values after that. If the fuel savings is 20.7 cents per mile for a hydrogen vehicle, penetration reaches 86% of new car sales by the 20th year. If the fuel savings is 0.5 cents per mile, market penetration reaches only 10% by the 20th year. To turn to vehicle price difference, if a hydrogen vehicle costs $2,000 less than a non-hydrogen vehicle, new car sales penetration reaches 92% by the 20th year. If a hydrogen vehicle costs $6,500 more than a non-hydrogen vehicle, market penetration is only 6% by the 20th year. Results from other sensitivity runs are presented. Policies that could affect hydrogen vehicle adoption are investigated. A tax credit for the purchase of a hydrogen vehicle of $2,500 tax credit results in 88% penetration by the 20th year, as compared with 60% in the benchmark case. If the tax credit is $6,000, penetration is 99% by the 20th year. Under a more modest approach, the tax credit would be available only for the first 10 years. Hydrogen sales penetration then reach 69% of sales by the 20th year with the $2,500 credit and 79% with the $6,000 credit. A carbon tax of $38 per metric ton is not

  1. Aircraft Carriers

    DEFF Research Database (Denmark)

    Nødskov, Kim; Kværnø, Ole

    as their purchases of aircraft carrier systems, makes it more than likely that the country is preparing such an acquisition. China has territorial disputes in the South China Sea over the Spratly Islands and is also worried about the security of its sea lines of communications, by which China transports the majority......, submarines, aircraft and helicopters, is not likely to be fully operational and war-capable until 2020, given the fact that China is starting from a clean sheet of paper. The United States of America (USA), the United Kingdom (UK), Russia and India are currently building or have made decisions to build new...

  2. Channel coding for underwater acoustic single-carrier CDMA communication system

    Science.gov (United States)

    Liu, Lanjun; Zhang, Yonglei; Zhang, Pengcheng; Zhou, Lin; Niu, Jiong

    2017-01-01

    CDMA is an effective multiple access protocol for underwater acoustic networks, and channel coding can effectively reduce the bit error rate (BER) of the underwater acoustic communication system. For the requirements of underwater acoustic mobile networks based on CDMA, an underwater acoustic single-carrier CDMA communication system (UWA/SCCDMA) based on the direct-sequence spread spectrum is proposed, and its channel coding scheme is studied based on convolution, RA, Turbo and LDPC coding respectively. The implementation steps of the Viterbi algorithm of convolutional coding, BP and minimum sum algorithms of RA coding, Log-MAP and SOVA algorithms of Turbo coding, and sum-product algorithm of LDPC coding are given. An UWA/SCCDMA simulation system based on Matlab is designed. Simulation results show that the UWA/SCCDMA based on RA, Turbo and LDPC coding have good performance such that the communication BER is all less than 10-6 in the underwater acoustic channel with low signal to noise ratio (SNR) from -12 dB to -10dB, which is about 2 orders of magnitude lower than that of the convolutional coding. The system based on Turbo coding with Log-MAP algorithm has the best performance.

  3. A Novel Algorithm for Efficient Downlink Packet Scheduling for Multiple-Component-Carrier Cellular Systems

    Directory of Open Access Journals (Sweden)

    Yao-Liang Chung

    2016-11-01

    Full Text Available The simultaneous aggregation of multiple component carriers (CCs for use by a base station constitutes one of the more promising strategies for providing substantially enhanced bandwidths for packet transmissions in 4th and 5th generation cellular systems. To the best of our knowledge, however, few previous studies have undertaken a thorough investigation of various performance aspects of the use of a simple yet effective packet scheduling algorithm in which multiple CCs are aggregated for transmission in such systems. Consequently, the present study presents an efficient packet scheduling algorithm designed on the basis of the proportional fair criterion for use in multiple-CC systems for downlink transmission. The proposed algorithm includes a focus on providing simultaneous transmission support for both real-time (RT and non-RT traffic. This algorithm can, when applied with sufficiently efficient designs, provide adequate utilization of spectrum resources for the purposes of transmissions, while also improving energy efficiency to some extent. According to simulation results, the performance of the proposed algorithm in terms of system throughput, mean delay, and fairness constitute substantial improvements over those of an algorithm in which the CCs are used independently instead of being aggregated.

  4. Hydrogen desorption reactions of Li-N-H hydrogen storage system: Estimation of activation free energy

    International Nuclear Information System (INIS)

    Matsumoto, Mitsuru; Haga, Tetsuya; Kawai, Yasuaki; Kojima, Yoshitsugu

    2007-01-01

    The dehydrogenation reactions of the mixtures of lithium amide (LiNH 2 ) and lithium hydride (LiH) were studied under an Ar atmosphere by means of temperature programmed desorption (TPD) technique. The dehydrogenation reaction of the LiNH 2 /LiH mixture was accelerated by addition of 1 mol% Ti(III) species (k = 3.1 x 10 -4 s -1 at 493 K), and prolonged ball-milling time (16 h) further enhanced reaction rate (k = 1.1 x 10 -3 s -1 at 493 K). For the hydrogen desorption reaction of Ti(III) doped samples, the activation energies estimated by Kissinger plot (95 kJ mol -1 ) and Arrhenius plot (110 kJ mol -1 ) were in reasonable agreement. The LiNH 2 /LiH mixture without Ti(III) species, exhibited slower hydrogen desorption process and the kinetic traces deviated from single exponential behavior. The results indicated the Ti(III) additives change the hydrogen desorption reaction mechanism of the LiNH 2 /LiH mixture

  5. Clean energy and the hydrogen economy.

    Science.gov (United States)

    Brandon, N P; Kurban, Z

    2017-07-28

    In recent years, new-found interest in the hydrogen economy from both industry and academia has helped to shed light on its potential. Hydrogen can enable an energy revolution by providing much needed flexibility in renewable energy systems. As a clean energy carrier, hydrogen offers a range of benefits for simultaneously decarbonizing the transport, residential, commercial and industrial sectors. Hydrogen is shown here to have synergies with other low-carbon alternatives, and can enable a more cost-effective transition to de-carbonized and cleaner energy systems. This paper presents the opportunities for the use of hydrogen in key sectors of the economy and identifies the benefits and challenges within the hydrogen supply chain for power-to-gas, power-to-power and gas-to-gas supply pathways. While industry players have already started the market introduction of hydrogen fuel cell systems, including fuel cell electric vehicles and micro-combined heat and power devices, the use of hydrogen at grid scale requires the challenges of clean hydrogen production, bulk storage and distribution to be resolved. Ultimately, greater government support, in partnership with industry and academia, is still needed to realize hydrogen's potential across all economic sectors.This article is part of the themed issue 'The challenges of hydrogen and metals'. © 2017 The Author(s).

  6. Effect of coexistent hydrogen isotopes on tracer diffusion of tritium in alpha phase of group-V metal-hydrogen systems

    International Nuclear Information System (INIS)

    Sakamoto, Kan; Hashizume, Kenichi; Sugisaki, Masayasu

    2009-01-01

    Tracer diffusion coefficients of tritium in the alpha phase of group-V metal-hydrogen systems, α-MH(D)xTy (M=V and Ta; x>>y), were measured in order to clarify the effects of coexistent hydrogen isotopes on the tritium diffusion behavior. The hydrogen concentration dependence of such behavior and the effects of the coexistent hydrogen isotopes (protium and deuterium) were determined. The results obtained in the present (for V and Ta) and previous (for Nb) studies revealed that tritium diffusion was definitely dependent on hydrogen concentration but was not so sensitive to the kind of coexistent hydrogen isotopes. By summarizing those data, it was found that the hydrogen concentration dependence of the tracer diffusion coefficient of tritium in the alpha phase of group-V metals could be roughly expressed by a single empirical curve. (author)

  7. ITER hydrogen isotope separation system conceptual design description

    International Nuclear Information System (INIS)

    Busigin, A.; Sood, S.K.; Kveton, O.K.; Dinner, P.J.; Murdoch, D.K.; Leger, D.

    1990-01-01

    This paper presents integrated hydrogen Isotope Separation System (ISS) designs for ITER based on requirements for plasma exhaust processing, neutral beam injection deuterium cleanup, pellet injector propellant detritiation, waste water detritiation, and breeding blanket detritiation. Specific ISS designs are developed for a machine with an aqueous lithium salt blanket (ALSB) and a machine with a solid ceramic breeding blanket (SBB). The differences in the ISS designs arising from the different blanket concepts are highlighted. It is found that the ISS designs for the two blanket concepts considered are very similar with the only major difference being the requirement for an additional large water distillation column for ALSB water detritiation. The extraction of tritium from the ALSB is based on flash evaporation to separate the blanket water from the dissolved Li salt, with the tritiated water then being fed to the ISS for detritiation. This technology is considered to be relatively well understood in comparison to front-end processes for SBB detritiation. In the design of the cryogenic distillation portion of the ISS, it was found that the tritium inventory could be very large (> 600 g) unless specific design measures were taken to reduce it. In the designs which are presented, the tritium inventory has been reduced to about 180 g, which is less than the ITER single-failure release limit of 200 g. Further design optimization and isolation of components is expected to reduce the inventory further. (orig.)

  8. Transfer Hydrogenation: Employing a Simple, In Situ Prepared Catalytic System

    KAUST Repository

    Ang, Eleanor Pei Ling

    2017-01-01

    Transfer hydrogenation has been recognized to be an important synthetic method in both academic and industrial research to obtain valuable products including alcohols. Transition metal catalysts based on precious metals, such as Ru, Rh and Ir

  9. Experimental-demonstrative system for energy conversion using hydrogen fuel cell - preliminary results

    International Nuclear Information System (INIS)

    Stoenescu, D.; Stefanescu, I.; Patularu, I.; Culcer, M.; Lazar, R.E.; Carcadea, E.; Mirica, D. . E-mail address of corresponding author: daniela@icsi.ro; Stoenescu, D.)

    2005-01-01

    It is well known that hydrogen is the most promising solution of future energy, both for long and medium term strategies. Hydrogen can be produced using many primary sources (natural gas, methane, biomass, etc.), it can be burned or chemically react having a high yield of energy conversion, being a non-polluted fuel. This paper presents the preliminary results obtained by ICSI Rm. Valcea in an experimental-demonstrative conversion energy system made by a sequence of hydrogen purification units and a CO removing reactors until a CO level lower than 10ppm, that finally feeds a hydrogen fuel stack. (author)

  10. Economics of producing hydrogen as transportation fuel using offshore wind energy systems

    International Nuclear Information System (INIS)

    Mathur, Jyotirmay; Agarwal, Nalin; Swaroop, Rakesh; Shah, Nikhar

    2008-01-01

    Over the past few years, hydrogen has been recognized as a suitable substitute for present vehicular fuels. This paper covers the economic analysis of one of the most promising hydrogen production methods-using wind energy for producing hydrogen through electrolysis of seawater-with a concentration on the Indian transport sector. The analysis provides insights about several questions such as the advantages of offshore plants over coastal installations, economics of large wind-machine clusters, and comparison of cost of producing hydrogen with competing gasoline. Robustness of results has been checked by developing several scenarios such as fast/slow learning rates for wind systems for determining future trends. Results of this analysis show that use of hydrogen for transportation is not likely to be attractive before 2012, and that too with considerable learning in wind, electrolyzer and hydrogen storage technology

  11. Concept and cost of a pipeline system to supply hydrogen to fuel cell cars in Germany; Konzept und Kosten eines Pipelinesystems zur Versorgung des deutschen Strassenverkehrs mit Wasserstoff

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, Dennis

    2012-11-01

    Fuel cells and hydrogen have the potential to be essential contributors for meeting the challenges of the future traffic sector. The key challenges include: - reducing global and local emissions - reducing import dependencies - preserving Germany's competitiveness - ensuring sufficient availability of the energy carrier Hydrogen is assumed to be the most appropriate energy carrier, since it can be produced via any primary energy and in terms of security is comparable to natural gas. In the long run, renewable energy, e.g. via wind power electrolysis, will make emission-free driving feasible. In order to use hydrogen to fuel cars, a comprehensive distribution infrastructure is required. This is completely different than the case of conventional fuels such as gasoline or diesel. Large amounts of hydrogen can be transported in a gaseous state in pipelines, as is common practice for natural gas. This option has not been examined to date. In particular, at the moment no suitable material has been identified for transporting hydrogen, which degrades the stability of the pipe. The aim of this thesis was to design a technical concept for a pipeline system that would make it possible to supply hydrogen to fuel cell cars. Using the assumptions of the study GermanHy, crucial technical questions were investigated. These questions comprise aspects such as general material requirements, feed-in, transportation and feed-out of the hydrogen. With respect to the material challenges, different potential possibilities are provided in order to ensure that no embrittlement will occur. Taking Germany as an example, the design and length of the pipeline system were investigated as well as the related economic and ecological aspects. A Monte Carlo simulation was conducted in order to calculate the probability density of both the investment and the specific cost. These results were placed in the overall context by calculating the economic impact of production, storage and fuelling stations

  12. Concept and cost of a pipeline system to supply hydrogen to fuel cell cars in Germany; Konzept und Kosten eines Pipelinesystems zur Versorgung des deutschen Strassenverkehrs mit Wasserstoff

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, Dennis

    2012-11-01

    Fuel cells and hydrogen have the potential to be essential contributors for meeting the challenges of the future traffic sector. The key challenges include: - reducing global and local emissions - reducing import dependencies - preserving Germany's competitiveness - ensuring sufficient availability of the energy carrier Hydrogen is assumed to be the most appropriate energy carrier, since it can be produced via any primary energy and in terms of security is comparable to natural gas. In the long run, renewable energy, e.g. via wind power electrolysis, will make emission-free driving feasible. In order to use hydrogen to fuel cars, a comprehensive distribution infrastructure is required. This is completely different than the case of conventional fuels such as gasoline or diesel. Large amounts of hydrogen can be transported in a gaseous state in pipelines, as is common practice for natural gas. This option has not been examined to date. In particular, at the moment no suitable material has been identified for transporting hydrogen, which degrades the stability of the pipe. The aim of this thesis was to design a technical concept for a pipeline system that would make it possible to supply hydrogen to fuel cell cars. Using the assumptions of the study GermanHy, crucial technical questions were investigated. These questions comprise aspects such as general material requirements, feed-in, transportation and feed-out of the hydrogen. With respect to the material challenges, different potential possibilities are provided in order to ensure that no embrittlement will occur. Taking Germany as an example, the design and length of the pipeline system were investigated as well as the related economic and ecological aspects. A Monte Carlo simulation was conducted in order to calculate the probability density of both the investment and the specific cost. These results were placed in the overall context by calculating the economic impact of production, storage and fuelling

  13. System Evaluation and Economic Analysis of a HTGR Powered High-Temperature Electrolysis Hydrogen Production Plant

    International Nuclear Information System (INIS)

    McKellar, Michael G.; Harvego, Edwin A.; Gandrik, Anastasia A.

    2010-01-01

    A design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322 C and 750 C, respectively. The power conversion unit will be a Rankine steam cycle with a power conversion efficiency of 40%. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 40.4% at a hydrogen production rate of 1.75 kg/s and an oxygen production rate of 13.8 kg/s. An economic analysis of this plant was performed with realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.67/kg of hydrogen assuming an internal rate of return, IRR, of 12% and a debt to equity ratio of 80%/20%. A second analysis shows that if the power cycle efficiency increases to 44.4%, the hydrogen production efficiency increases to 42.8% and the hydrogen and oxygen production rates are 1.85 kg/s and 14.6 kg/s respectively. At the higher power cycle efficiency and an IRR of 12% the cost of hydrogen production is $3.50/kg.

  14. Optimizing investments in coupled offshore wind -electrolytic hydrogen storage systems in Denmark

    Science.gov (United States)

    Hou, Peng; Enevoldsen, Peter; Eichman, Joshua; Hu, Weihao; Jacobson, Mark Z.; Chen, Zhe

    2017-08-01

    In response to electricity markets with growing levels of wind energy production and varying electricity prices, this research examines incentives for investments in integrated renewable energy power systems. A strategy for using optimization methods for a power system consisting of wind turbines, electrolyzers, and hydrogen fuel cells is explored. This research reveals the investment potential of coupling offshore wind farms with different hydrogen systems. The benefits in terms of a return on investment are demonstrated with data from the Danish electricity markets. This research also investigates the tradeoffs between selling the hydrogen directly to customers or using it as a storage medium to re-generate electricity at a time when it is more valuable. This research finds that the most beneficial configuration is to produce hydrogen at a time that complements the wind farm and sell the hydrogen directly to end users.

  15. Prospects for hydrogen storage in graphene.

    Science.gov (United States)

    Tozzini, Valentina; Pellegrini, Vittorio

    2013-01-07

    Hydrogen-based fuel cells are promising solutions for the efficient and clean delivery of electricity. Since hydrogen is an energy carrier, a key step for the development of a reliable hydrogen-based technology requires solving the issue of storage and transport of hydrogen. Several proposals based on the design of advanced materials such as metal hydrides and carbon structures have been made to overcome the limitations of the conventional solution of compressing or liquefying hydrogen in tanks. Nevertheless none of these systems are currently offering the required performances in terms of hydrogen storage capacity and control of adsorption/desorption processes. Therefore the problem of hydrogen storage remains so far unsolved and it continues to represent a significant bottleneck to the advancement and proliferation of fuel cell and hydrogen technologies. Recently, however, several studies on graphene, the one-atom-thick membrane of carbon atoms packed in a honeycomb lattice, have highlighted the potentialities of this material for hydrogen storage and raise new hopes for the development of an efficient solid-state hydrogen storage device. Here we review on-going efforts and studies on functionalized and nanostructured graphene for hydrogen storage and suggest possible developments for efficient storage/release of hydrogen under ambient conditions.

  16. 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.

  17. Artificial neural networks and neuro-fuzzy inference systems as virtual sensors for hydrogen safety prediction

    Energy Technology Data Exchange (ETDEWEB)

    Karri, Vishy; Ho, Tien [School of Engineering, University of Tasmania, GPO Box 252-65, Hobart, Tasmania 7001 (Australia); Madsen, Ole [Department of Production, Aalborg University, Fibigerstraede 16, DK-9220 Aalborg (Denmark)

    2008-06-15

    Hydrogen is increasingly investigated as an alternative fuel to petroleum products in running internal combustion engines and as powering remote area power systems using generators. The safety issues related to hydrogen gas are further exasperated by expensive instrumentation required to measure the percentage of explosive limits, flow rates and production pressure. This paper investigates the use of model based virtual sensors (rather than expensive physical sensors) in connection with hydrogen production with a Hogen 20 electrolyzer system. The virtual sensors are used to predict relevant hydrogen safety parameters, such as the percentage of lower explosive limit, hydrogen pressure and hydrogen flow rate as a function of different input conditions of power supplied (voltage and current), the feed of de-ionized water and Hogen 20 electrolyzer system parameters. The virtual sensors are developed by means of the application of various Artificial Intelligent techniques. To train and appraise the neural network models as virtual sensors, the Hogen 20 electrolyzer is instrumented with necessary sensors to gather experimental data which together with MATLAB neural networks toolbox and tailor made adaptive neuro-fuzzy inference systems (ANFIS) were used as predictive tools to estimate hydrogen safety parameters. It was shown that using the neural networks hydrogen safety parameters were predicted to less than 3% of percentage average root mean square error. The most accurate prediction was achieved by using ANFIS. (author)

  18. Hydrogen: the great debate. 'Power to Gas - how to cope with the challenge of electricity storage?; Hydrogen in energy transition: which challenges to be faced?; Hydrogen, essential today, indispensable tomorrow; Electrolytic hydrogen, a solution for energy transition?; Development of high power electrolysis systems: need and approach; Hydrogen as energy vector, Potential and stakes: a perspective; The Toyota Fuel Cell System: a new era for the automotive industry; Three key factors: production, applications to mobility, and public acceptance; Hydrogen, benevolent fairy or tempting demon

    International Nuclear Information System (INIS)

    Hauet, Jean-Pierre; Boucly, Philippe; Beeker, Etienne; Mauberger, Pascal; Quint, Aliette; Pierre, Helene; Lucchese, Paul; Bouillon-Delporte, Valerie; Chauvet, Bertrand; Brisse, Annabelle; Gautier, Ludmila; Hercberg, Sylvain; De Volder, Marc; Gruson, Jean-Francois; Marion, Pierre; Grellier, Sebastien; Devezeaux, Jean-Guy; Mansilla, Christine; Le Net, Elisabeth; Le Duigou, Alain; Maire, Jacques

    2015-01-01

    This publication proposes a set of contributions which address various issues related to the development of the use of hydrogen as an energy source. More precisely, these contributions discuss how to face the challenge of electricity storage by using the Power-to-Gas technology, the challenges to be faced regarding the role of hydrogen in energy transition, the essential current role of hydrogen and its indispensable role for tomorrow, the possible role of electrolytic hydrogen as a solution for energy transition, the need of and the approach to a development of high power electrolysis systems, the potential and stakes of hydrogen as an energy vector, the Toyota fuel cell system as a sign for new era for automotive industry, the three main factors (production, applications to mobility, and public acceptance) for the use of hydrogen in energy transition, and the role of hydrogen perceived either as a benevolent fairy or a tempting demon

  19. On the solubility of hydrogen in the systems titanium-aluminium-hydrogen, titanium-vanadium-hydrogen and titanium-aluminium-vanadium-hydrogen in the temperature region of 800 to 1,0000C at hydrogen pressures of 0.1 to 400 mm.Hg

    International Nuclear Information System (INIS)

    Kauder, G.W.

    1973-01-01

    The hydrogen concentrations on Ti-Al, Ti-V and Ti-Al-V alloys were determined in the temperature region from 800 to 1,000 0 C and at hydrogen pressures of 0.1 to 400 mm.Hg using a gravimetric measuring process. The thus obtained results allowed the drawing of hydrogen activity slopes in the titanium rich corner of the systems titanium-hydrogen, titanium-aluminium-hydrogen, titanium-vanadium-hydrogen and such for the technical titanium alloys Ti-6Al-4V and Ti-6Al-6V. In spite of the antagonistic effects of the elements aluminium and vanadium on the stabilization of the α and β phase regions of titanium, a hydrogen-activity-increasing effect was always found in which the aluminium influence was greater than that of vanadium. Breaks occured in the hydrogen activity curves and phase boundaries, and phase regions were determined over their positions. Isothermal phase diagrams for the titanium-rich corner of the system titanium-aluminium-hydrogen at 800, 850 and 900 0 C and for the titanium-rich corner of the titanium-vanadium-hydrogen system at 900, 950 and 1,000 0 C were drawn up from the hydrogen activity curves. (orig./LH) [de

  20. Enhanced Dissolution of a Porous Carrier-Containing Ternary Amorphous Solid Dispersion System Prepared by a Hot Melt Method.

    Science.gov (United States)

    Hanada, Masataka; Jermain, Scott V; Williams, Robert O

    2018-01-01

    The focus of our study was to employ a solvent-free, thermal process to evaluate the use of a porous carrier in a drug-polymer-porous carrier ternary formulation containing a high drug load (e.g., ≥50% w/w). The purpose of the study was to improve the dissolution properties of the biopharmaceutical classification system class II drug, indomethacin, in the ternary formulation. The effect that the selected polymer has on properties of the formulation was studied, and the formulation characteristics of hypromellose (AF15), copovidone (VA64), and polyvinyl alcohol-polyethylene glycol graft copolymer was evaluated to understand differences in dissolution rates and drug adsorption onto the porous carrier. The ternary formulations were manufactured using a thermal technique that relied on heating and mixing, without the necessity of mechanical shear. All thermally processed granules that employed the porous carrier exhibited immediate release compared with crystalline indomethacin and physical mixtures. In addition, the ternary formulations maintained supersaturation compared with the binary formulations without polymer. The results of this study indicated that the thermally processed ternary formulations containing a porous carrier demonstrated a much improved dissolution profile in nonsink conditions. Copyright © 2018 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  1. The esophageal transit in normal persons and in carrier of Chagas disease and progressive systemic sclerosis. A scintiscanning study

    International Nuclear Information System (INIS)

    Oliveira, R.B. de.

    1985-01-01

    The aim of this study is determine, by a scintiscanning method, how 10 ml of water, swallowed at one time, transit by the esophagus of normal persons and carriers of diseases, that attacking the esophagus motility. The other aim was determine the characteristics of the transit by the esophagus in carriers of chagasic esophagus diseases and of progressive systemic sclerosis. The study of esophageal transit was made by the technetium 99, with a gamma camera for detecting and quantifying the radioactivity. Several images of the esophageal transit, with persons in supine and seat positions, for processing the radioactivity curves x time are studied and compared. (C.G.C.)

  2. Development of accident event trees and evaluation of safety system failure modes for the nuclear ultra large crude carrier

    International Nuclear Information System (INIS)

    Lewe, C.K.; Coffey, R.S.; Goodwin, E.F.; Maltese, J.G.; Pyatt, D.W.

    1978-01-01

    A method of applying the probabilistic accident event tree methodology to safety assessments of a nuclear powered Ultra Large Crude Carrier is presented. Also presented are the procedures by which an external accident initiating event, such as a ship collision, may be correlated with the probabilities of damage to the ship's safety systems and to their ultimate availabilities to perform required safety functions

  3. Timing Metrics of Joint Timing and Carrier-Frequency Offset Estimation Algorithms for TDD-based OFDM systems

    NARCIS (Netherlands)

    Hoeksema, F.W.; Srinivasan, R.; Schiphorst, Roelof; Slump, Cornelis H.

    2004-01-01

    In joint timing and carrier offset estimation algorithms for Time Division Duplexing (TDD) OFDM systems, different timing metrics are proposed to determine the beginning of a burst or symbol. In this contribution we investigated the different timing metrics in order to establish their impact on the

  4. Buparvaquone Nanostructured Lipid Carrier: Development of an Affordable Delivery System for the Treatment of Leishmaniases.

    Science.gov (United States)

    Monteiro, Lis Marie; Löbenberg, Raimar; Cotrim, Paulo Cesar; Barros de Araujo, Gabriel Lima; Bou-Chacra, Nádia

    2017-01-01

    Buparvaquone (BPQ), a veterinary drug, was formulated as nanostructured lipid carriers (NLC) for leishmaniases treatment. The formulation design addressed poor water solubility of BPQ and lack of human drug delivery system. The DSC/TG and microscopy methods were used for solid lipids screening. Softisan® 154 showed highest BPQ solubility in both methods. The BPQ solubility in liquid lipids using HPLC revealed Miglyol® 812 as the best option. Response surface methodology (RSM) was used to identify the optimal Softisan154 : Miglyol 812 ratios (7 : 10 to 2 : 1) and Kolliphor® P188 and Tween® 80 concentration (>3.0% w/w) aiming for z -average in the range of 100-300 nm for macrophage delivery. The NLC obtained by high-pressure homogenization showed low z -averages (<350 nm), polydispersity (<0.3), and encapsulation efficiency close to 100%. DSC/TG and microscopy in combination proved to be a powerful tool to select the solid lipid. The relationship among the variables, demonstrated by a linear mathematical model using RSM, allowed generating a design space. This design space showed the limits in which changes in the variables influenced the z -average. Therefore, these drug delivery systems have the potential to improve the availability of affordable medicines due to the low cost of raw materials, using well established, reliable, and feasible scale-up technology.

  5. Buparvaquone Nanostructured Lipid Carrier: Development of an Affordable Delivery System for the Treatment of Leishmaniases

    Directory of Open Access Journals (Sweden)

    Lis Marie Monteiro

    2017-01-01

    Full Text Available Buparvaquone (BPQ, a veterinary drug, was formulated as nanostructured lipid carriers (NLC for leishmaniases treatment. The formulation design addressed poor water solubility of BPQ and lack of human drug delivery system. The DSC/TG and microscopy methods were used for solid lipids screening. Softisan® 154 showed highest BPQ solubility in both methods. The BPQ solubility in liquid lipids using HPLC revealed Miglyol® 812 as the best option. Response surface methodology (RSM was used to identify the optimal Softisan154 : Miglyol 812 ratios (7 : 10 to 2 : 1 and Kolliphor® P188 and Tween® 80 concentration (>3.0% w/w aiming for z-average in the range of 100–300 nm for macrophage delivery. The NLC obtained by high-pressure homogenization showed low z-averages (<350 nm, polydispersity (<0.3, and encapsulation efficiency close to 100%. DSC/TG and microscopy in combination proved to be a powerful tool to select the solid lipid. The relationship among the variables, demonstrated by a linear mathematical model using RSM, allowed generating a design space. This design space showed the limits in which changes in the variables influenced the z-average. Therefore, these drug delivery systems have the potential to improve the availability of affordable medicines due to the low cost of raw materials, using well established, reliable, and feasible scale-up technology.

  6. PLGA based drug delivery systems: Promising carriers for wound healing activity.

    Science.gov (United States)

    Chereddy, Kiran Kumar; Vandermeulen, Gaëlle; Préat, Véronique

    2016-03-01

    Wound treatment remains one of the most prevalent and economically burdensome healthcare issues in the world. Current treatment options are limited and require repeated administrations which led to the development of new therapeutics to satisfy the unmet clinical needs. Many potent wound healing agents were discovered but most of them are fragile and/or sensitive to in vivo conditions. Poly(lactic-co-glycolic acid) (PLGA) is a widely used biodegradable polymer approved by food and drug administration and European medicines agency as an excipient for parenteral administrations. It is a well-established drug delivery system in various medical applications. The aim of the current review is to elaborate the applications of PLGA based drug delivery systems carrying different wound healing agents and also present PLGA itself as a wound healing promoter. PLGA carriers encapsulating drugs such as antibiotics, anti-inflammatory drugs, proteins/peptides, and nucleic acids targeting various phases/signaling cycles of wound healing, are discussed with examples. The combined therapeutic effects of PLGA and a loaded drug on wound healing are also mentioned. © 2016 by the Wound Healing Society.

  7. A simple carrier frequency offset synchronization strategy for multiple relay cooperative diversity ofdm system

    International Nuclear Information System (INIS)

    Mudassar, I.; Cheema, A.; Shoab, A.

    2014-01-01

    Cooperative Diversity Orthogonal Frequency Division Modulation (CD-OFDM) systems are very sensitive to synchronization errors. In CD-OFDM, synchronization is more complex because all cooperative nodes (CNs) have their own frequency oscillator and different channel path which results in different timing and carrier frequency offset (CFO) for each node. Consequently, each node has to be synchronized separately without affecting the synchronization process of other nodes. All CNs transmit simultaneously during cooperation phase (C-phase) and their aggregate signal is received at the destination node. A unique frequency domain (FD) preamble is proposed for each CN during C-phase that will allow simple separation of cooperative nodes. These FD multiplexed preambles make the synchronization problem identical to OFDMA uplink. OFDMA system typically uses highly complex iterative CFO estimators for uplink synchronization. However, a simple one-shot CFO estimator is proposed that uses repeated preamble of two OFDM symbol duration. The proposed method is computationally efficient because it relies on FFT operation for user separation and interference mitigation. Subsequently, time domain (TD) multiplication is used for CFO correction of each CN. Furthermore, a CD-OFDM protocol for data transmission is presented that suites the proposed estimator and harnesses spatial diversity. The proposed estimator shows good statistical results during simulations in AWGN and Rayleigh environments. During evaluation, estimator variance, mean square error and symbol error rate are used as performance measure. (author)

  8. 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.

  9. Investigation into periodic process of hydrogen isotope separation by counterflow method in the hydrogen-palladium system

    International Nuclear Information System (INIS)

    Andreev, B.M.; Selivanenko, I.L.; Vedeneev, A.I.; Golubkov, A.N.; Tenyaev, B.N.

    1999-01-01

    The key diagram and results of the investigation into working conditions of the pilot plant for hydrogen isotope separation embodying the concept of continuous counterflow separation in the hydrogen-palladium system are shown. The counterflow of phases in the plant is attained under the motion of palladium solid hydride phase relative to stationary blocks of flow rotation. The column separator is defined as section type one. The plant performs in periodic regime with accumulating vessels for light and heavy components of the separated mixture. Maximum concentration of the separated tritium ranged up to ∼ 96 % in the experiments of the deuterium-tritium separation. Minimum concentration of the residual tritium in the mixture ranged up to ∼ 0.1 %. The plant provides to reprocessing 4.5 moles of the gas a day [ru

  10. The Role of Hydrogen Sulfide in Renal System.

    Science.gov (United States)

    Cao, Xu; Bian, Jin-Song

    2016-01-01

    Hydrogen sulfide has gained recognition as the third gaseous signaling molecule after nitric oxide and carbon monoxide. This review surveys the emerging role of H 2 S in mammalian renal system, with emphasis on both renal physiology and diseases. H 2 S is produced redundantly by four pathways in kidney, indicating the abundance of this gaseous molecule in the organ. In physiological conditions, H 2 S was found to regulate the excretory function of the kidney possibly by the inhibitory effect on sodium transporters on renal tubular cells. Likewise, it also influences the release of renin from juxtaglomerular cells and thereby modulates blood pressure. A possible role of H 2 S as an oxygen sensor has also been discussed, especially at renal medulla. Alternation of H 2 S level has been implicated in various pathological conditions such as renal ischemia/reperfusion, obstructive nephropathy, diabetic nephropathy, and hypertensive nephropathy. Moreover, H 2 S donors exhibit broad beneficial effects in renal diseases although a few conflicts need to be resolved. Further research reveals that multiple mechanisms are underlying the protective effects of H 2 S, including anti-inflammation, anti-oxidation, and anti-apoptosis. In the review, several research directions are also proposed including the role of mitochondrial H 2 S in renal diseases, H 2 S delivery to kidney by targeting D-amino acid oxidase/3-mercaptopyruvate sulfurtransferase (DAO/3-MST) pathway, effect of drug-like H 2 S donors in kidney diseases and understanding the molecular mechanism of H 2 S. The completion of the studies in these directions will not only improves our understanding of renal H 2 S functions but may also be critical to translate H 2 S to be a new therapy for renal diseases.

  11. Transfer Hydrogenation: Employing a Simple, In Situ Prepared Catalytic System

    KAUST Repository

    Ang, Eleanor Pei Ling

    2017-04-01

    Transfer hydrogenation has been recognized to be an important synthetic method in both academic and industrial research to obtain valuable products including alcohols. Transition metal catalysts based on precious metals, such as Ru, Rh and Ir, are typically employed for this process. In recent years, iron-based catalysts have attracted considerable attention as a greener and more sustainable alternative since iron is earth abundant, inexpensive and non-toxic. In this work, a combination of iron disulfide with chelating bipyridine ligand was found to be effective for the transfer hydrogenation of a variety of ketones to the corresponding alcohols in the presence of a simple base. It provided a convenient and economical way to conduct transfer hydrogenation. A plausible role of sulfide next to the metal center in facilitating the catalytic reaction is demonstrated.

  12. Nuclear power plant equipped with hydrogen removing system

    International Nuclear Information System (INIS)

    Ezawa, Shin-ichi; Yamanari, Shozo; Okura, Minoru; Kamizuma, Nobuaki.

    1998-01-01

    A γ-shield and container spray pipelines are disposed to an upper dry well in a reactor container incorporating a reactor pressure vessel. A plurality of catalytic hydrogen removing devices are disposed close to a wall on the side of the pressure vessel in the dry well and a wall on the side of the outer wall of the reactor container. The plurality of catalytic hydrogen removing devices are disposed substantially equally in horizontal direction and circumferential direction of the side walls. If container spray water is sprayed, the atmospheric gases in the reactor are compulsory circulated. In addition, since the temperature of the γ-shield is higher than the atmospheric temperature, spontaneous circulation is caused. As a result, rising currents of gases are formed at regions in the vicinity of the γ-shield. The catalytic hydrogen removing devices are disposed to the places where the rising currents are formed. (I.N.)

  13. Hydrogen Generation, Combustibility and Mitigation in Nuclear Power Plant Systems

    International Nuclear Information System (INIS)

    Talha, K.A.; El-Sheikh, B.M.; Gad El-Mawla, A.S.

    2003-01-01

    The nuclear power plant is provided with features to insure safety. The engineered safety features (ESFs) are devoted to set operating conditions under accident conditions. If ESFs fail to apply in some accidents, this would lead to what called severe accidents, and core damage. In this case hydrogen will be generated from different sources particularly from metal-water reactions. Since the containment is the final barrier to protect the environment from the release of radioactive materials; its integrity should not be threatened. In recent years, hydrogen concentration represents a real problem if it exceeds the combustibility limits. This work is devoted to calculate the amount of hydrogen to be generated, indelicate its combustibility and how to inertize the containment using different gases to maintain its integrity and protect the environment from the release of radioactive materials

  14. Basic principles on the safety evaluation of the HTGR hydrogen production system

    International Nuclear Information System (INIS)

    Ohashi, Kazutaka; Nishihara, Tetsuo; Tazawa, Yujiro; Tachibana, Yukio; Kunitomi, Kazuhiko

    2009-03-01

    As HTGR hydrogen production systems, such as HTTR-IS system or GTHTR300C currently being developed by Japan Atomic Energy Agency, consists of nuclear reactor and chemical plant, which are without a precedent in the world, safety design philosophy and regulatory framework should be newly developed. In this report, phenomena to be considered and events to be postulated in the safety evaluation of the HTGR hydrogen production systems were investigated and basic principles to establish acceptance criteria for the explosion and toxic gas release accidents were provided. Especially for the explosion accident, quantitative criteria to the reactor building are proposed with relating sample calculation results. It is necessary to treat abnormal events occurred in the hydrogen production system as an 'external events to the nuclear plant' in order to classify the hydrogen production system as no-nuclear facility' and basic policy to meet such requirement was also provided. (author)

  15. Development of Al2O3 carrier-Ru composite catalyst for hydrogen generation from alkaline NaBH4 hydrolysis

    International Nuclear Information System (INIS)

    Huang, Yao-Hui; Su, Chia-Chi; Wang, Shu-Ling; Lu, Ming-Chun

    2012-01-01

    A recyclable and reusable Ru/Al 2 O 3 catalyst is prepared for hydrogen generation from the hydrolysis process of alkaline sodium borohydride (NaBH 4 ) solution. The hydrogen generation rate by the hydrolysis and methanolysis of alkaline NaBH 4 was explored as a function of NaOH concentration. Meantime, the byproducts derived from the spent alkaline NaBH 4 solution were characterized by X-ray diffraction (XRD), scanning electro microscope/energy dispersive spectrometer (SEM/EDS) and NMR (Nuclear Magnetic Resonance). The effect of NaOH concentration on the hydrogen generation from the hydrolysis of NaBH 4 significantly depends on the type of catalysts. With increasing NaOH concentration, the hydrogen generation rates decrease when using ruthenium (Ru) composite as a catalyst. The hydrogen generation rate of the methanolysis of NaBH 4 is significantly inhibited in the presence of NaOH as compared with the hydrolysis of NaBH 4 . The durability test of the Ru/Al 2 O 3 catalyst shows that the hydrogen generation rate decreases with recycling and reuse. The XRD and NMR analysis results show that the borate hydrate (NaBO 2 H 2 O) was derived from the hydrolysis of 20 wt% and 30 wt% NaBH 4 . -- Highlights: ► A recyclable Ru/Al 2 O 3 catalyst was synthesized for hydrogen generation. ► Ru/Al 2 O 3 significantly promotes the hydrogen generation rate from alkaline NaBH 4 solution. ► The prepared Ru/Al 2 O 3 catalyst can easily collect from the spent alkaline NaBH 4 solution.

  16. Simulations of magnetic capturing of drug carriers in the brain vascular system

    Energy Technology Data Exchange (ETDEWEB)

    Kenjeres, S., E-mail: S.Kenjeres@tudelft.nl [Department of Multi-Scale Physics, Faculty of Applied Sciences, J.M. Burgerscentre for Fluid Dynamics, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft (Netherlands); Righolt, B.W. [Department of Multi-Scale Physics, Faculty of Applied Sciences, J.M. Burgerscentre for Fluid Dynamics, Delft University of Technology, Leeghwaterstraat 39, 2628 CB Delft (Netherlands)

    2012-06-15

    Highlights: Black-Right-Pointing-Pointer Blood flow and magnetic particles distributions in the brain vascular system simulated. Black-Right-Pointing-Pointer Numerical mesh generated from raw MRI images. Black-Right-Pointing-Pointer Significant increase in local capturing of magnetic particles obtained. Black-Right-Pointing-Pointer Promising technique for localised non-invasive treatment of brain tumours. - Abstract: The present paper reports on numerical simulations of blood flow and magnetic drug carrier distributions in a complex brain vascular system. The blood is represented as a non-Newtonian fluid by the generalised power law. The Lagrangian tracking of the double-layer spherical particles is performed to estimate particle deposition under influence of imposed magnetic field gradients across arterial walls. Two situations are considered: neutral (magnetic field off) and active control (magnetic field on) case. The double-layer spherical particles that mimic a real medical drug are characterised by two characteristic diameters - the outer one and the inner one of the magnetic core. A numerical mesh of the brain vascular system consisting of multi-branching arteries is generated from raw MRI scan images of a patient. The blood is supplied through four main inlet arteries and the entire vascular system includes more than 30 outlets, which are modelled by Murray's law. The no-slip boundary condition is applied for velocity components along the smooth and rigid arterial walls. Numerical simulations revealed detailed insights into blood flow patterns, wall-shear-stress and local particle deposition efficiency along arterial walls. It is demonstrated that magnetically targeted drug delivery significantly increased the particle capturing efficiency in the pre-defined regions. This feature can be potentially useful for localised, non-invasive treatment of brain tumours.

  17. Hybrid Theory of Electron-Hydrogenic Systems Elastic Scattering

    Science.gov (United States)

    Bhatia, A. K.

    2007-01-01

    Accurate electron-hydrogen and electron-hydrogenic cross sections are required to interpret fusion experiments, laboratory plasma physics and properties of the solar and astrophysical plasmas. We have developed a method in which the short-range and long-range correlations can be included at the same time in the scattering equations. The phase shifts have rigorous lower bounds and the scattering lengths have rigorous upper bounds. The phase shifts in the resonance region can be used to calculate very accurately the resonance parameters.

  18. A synergetic use of hydrogen and fuel cells in human spaceflight power systems

    Science.gov (United States)

    Belz, S.

    2016-04-01

    Hydrogen is very flexible in different fields of application of energy conversion. It can be generated by water electrolysis. Stored in tanks it is available for re-electrification by fuel cells. But it is not only the power system, which benefits from use of hydrogen, but also the life support system, which can contain hydrogen consuming technologies for recycling management (e.g. carbon dioxide removal and waste combustion processes). This paper points out various fields of hydrogen use in a human spaceflight system. Depending on mission scenarios, shadow phases, and the need of energy storage, regenerative fuel cell systems can be more efficient than secondary batteries. Here, different power storage concepts are compared by equivalent system mass calculation, thus including impact in the peripheral structure (volume, thermal management, etc.) on the space system. It is also focused on the technical integration aspect, e.g. which peripheral components have to be adapted when hydrogen is also used for life support technologies and what system mass benefit can be expected. Finally, a recommendation is given for the following development steps for a synergetic use of hydrogen and fuel cells in human spaceflight power systems.

  19. Techno-economic analysis of an autonomous power system integrating hydrogen technology as energy storage medium

    Energy Technology Data Exchange (ETDEWEB)

    Tzamalis, G. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece); Zoulias, E.I.; Stamatakis, E.; Varkaraki, E. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Lois, E.; Zannikos, F. [Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece)

    2011-01-15

    Two different options for the autonomous power supply of rural or/and remote buildings are examined in this study. The first one involves a PV - diesel based power system, while the second one integrates RES and hydrogen technologies for the development of a self - sustained power system. The main objective is the replacement of the diesel generator and a comparison between these two options for autonomous power supply. Model simulations of the two power systems before and after the replacement, an optimization of the component sizes and a techno - economic analysis have been performed for the purpose of this study. A sensitivity analysis taking into account future cost scenarios for hydrogen technologies is also presented. The results clearly show that the Cost of Energy Produced (COE) from the PV - hydrogen technologies power system is extremely higher than the PV - diesel power system. However, the adopted PV - hydrogen technologies power system reduces to zero the Green - House Gas (GHG) emissions. Moreover, the sensitivity analysis indicates that COE for the latter system can be further reduced by approximately 50% compared to its initial value. This could be achieved by reducing critical COE's parameters, such as PEM electrolyser and fuel cell capital costs. Hence, a possible reduction on the capital costs of hydrogen energy equipment in combination with emissions reduction mentioned above could make hydrogen - based power systems more competitive. (author)

  20. Zein Nanoparticles as Eco-Friendly Carrier Systems for Botanical Repellents Aiming Sustainable Agriculture.

    Science.gov (United States)

    Oliveira, Jhones L de; Campos, Estefânia V R; Pereira, Anderson E S; Pasquoto, Tatiane; Lima, Renata; Grillo, Renato; Andrade, Daniel Junior de; Santos, Fabiano Aparecido Dos; Fraceto, Leonardo Fernandes

    2018-02-14

    Botanical repellents represent one of the main ways of reducing the use of synthetic pesticides and the contamination of soil and hydric resources. However, the poor stability and rapid degradation of these compounds in the environment hinder their effective application in the field. Zein nanoparticles can be used as eco-friendly carrier systems to protect these substances against premature degradation, provide desirable release characteristics, and reduce toxicity in the environment and to humans. In this study, we describe the preparation and characterization of zein nanoparticles loaded with the main constituents of the essential oil of citronella (geraniol and R-citronellal). The phytotoxicity, cytotoxicity, and insect activity of the nanoparticles toward target and nontarget organisms were also evaluated. The botanical formulations showed high encapsulation efficiency (>90%) in the nanoparticles, good physicochemical stability, and effective protection of the repellents against UV degradation. Cytotoxicity and phytotoxicity assays showed that encapsulation of the botanical repellents decreased their toxicity. Repellent activity tests showed that nanoparticles containing the botanical repellents were highly repellent against the Tetranychus urticae Koch mite. This nanotechnological formulation offers a new option for the effective use of botanical repellents in agriculture, reducing toxicity, protecting against premature degradation, and providing effective pest control.

  1. Blind Estimation of the Phase and Carrier Frequency Offsets for LDPC-Coded Systems

    Directory of Open Access Journals (Sweden)

    Houcke Sebastien

    2010-01-01

    Full Text Available Abstract We consider in this paper the problem of phase offset and Carrier Frequency Offset (CFO estimation for Low-Density Parity-Check (LDPC coded systems. We propose new blind estimation techniques based on the calculation and minimization of functions of the Log-Likelihood Ratios (LLR of the syndrome elements obtained according to the parity check matrix of the error-correcting code. In the first part of this paper, we consider phase offset estimation for a Binary Phase Shift Keying (BPSK modulation and propose a novel estimation technique. Simulation results show that the proposed method is very effective and outperforms many existing algorithms. Then, we modify the estimation criterion so that it can work for higher-order modulations. One interesting feature of the proposed algorithm when applied to high-order modulations is that the phase offset of the channel can be blindly estimated without any ambiguity. In the second part of the paper, we consider the problem of CFO estimation and propose estimation techniques that are based on the same concept as the ones presented for the phase offset estimation. The Mean Squared Error (MSE and Bit Error Rate (BER curves show the efficiency of the proposed estimation techniques.

  2. A Novel Power-Saving Transmission Scheme for Multiple-Component-Carrier Cellular Systems

    Directory of Open Access Journals (Sweden)

    Yao-Liang Chung

    2016-04-01

    Full Text Available As mobile data traffic levels have increased exponentially, resulting in rising energy costs in recent years, the demand for and development of green communication technologies has resulted in various energy-saving designs for cellular systems. At the same time, recent technological advances have allowed multiple component carriers (CCs to be simultaneously utilized in a base station (BS, a development that has made the energy consumption of BSs a matter of increasing concern. To help address this concern, herein we propose a novel scheme aimed at efficiently minimizing the power consumption of BS transceivers during transmission, while still ensuring good service quality and fairness for users. Specifically, the scheme utilizes the dynamic activation/deactivation of CCs during data transmission to increase power usage efficiency. To test its effectiveness, the proposed scheme was applied to a model consisting of a BS with orthogonal frequency division multiple access-based CCs in a downlink transmission environment. The results indicated that, given periods of relatively light traffic loads, the total power consumption of the proposed scheme is significantly lower than that of schemes in which all the CCs of a BS are constantly activated, suggesting the scheme’s potential for reducing both energy costs and carbon dioxide emissions.

  3. Liposomes as potential carrier system for targeted delivery of polyene antibiotics.

    Science.gov (United States)

    Naik, Suresh R; Desai, Sandhya K; Shah, Priyank D; Wala, Santosh M

    2013-09-01

    The development of new therapeutic modalities involves the use of drug carrier, such as liposomes, which can modify pharmacokinetic and bio-distribution of drug profile. Polyene antibiotics incorporation into liposomes improves its availability at the site, bio-distribution and therapeutic index mainly through the engulfment of liposomes by circulating monocytes/macrophages and transportation to the site of infection. Polyene antibiotics (AmB, SJA-95, HA-1-92) and other antibiotics (streptomycin, tobramycin, quinolones, anti-tubercular and anti-cancer drugs), liposomal preparations are described with possible advantages from therapeutic efficacy and toxicity point of view. The polyene macrolide antibiotics liposomal preparations proved to be more effective in the treatment of systemic mycosis. The AmB-cyclodextrin derivatives inclusion complex is a major breakthrough in liposomal preparation which can be converted into aqueous phase of liposome. Liposomal drug incorporated preparation has been one of the important areas of research for developing the existing polyene antibiotics into useful chemotherapeutic agents in clinical medicine. In recent past other antibiotics have also been incorporated into liposomes using wide variety of materials, phosphatidylethanolamine derivatives (pegylated liposomes, enzyme sensitive conjugates, fluidosomes of anti-cancer drugs and poly lactic/glycolic acid microspheres for anti-tuberculosis drugs). In addition, attempts were also made to extend the receptor mediated drug targeting and to review some relevant patents.

  4. 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)

  5. The Assessment of Hydrogen Energy Systems for Fuel Cell Vehicles Using Principal Componenet Analysis and Cluster Analysis

    DEFF Research Database (Denmark)

    Ren, Jingzheng; Tan, Shiyu; Dong, Lichun

    2012-01-01

    and analysis of the hydrogen systems is meaningful for decision makers to select the best scenario. principal component analysis (PCA) has been used to evaluate the integrated performance of different hydrogen energy systems and select the best scenario, and hierarchical cluster analysis (CA) has been used...... for transportation of hydrogen, hydrogen gas tank for the storage of hydrogen at refueling stations, and gaseous hydrogen as power energy for fuel cell vehicles has been recognized as the best scenario. Also, the clustering results calculated by CA are consistent with those determined by PCA, denoting...

  6. Hydrogen spillover on DV (555-777) graphene – vanadium cluster system: First principles study

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, E. Mathan, E-mail: ranjit.t@res.srmuniv.ac.in, E-mail: mathanranjitha@gmail.com; Thapa, Ranjit, E-mail: ranjit.t@res.srmuniv.ac.in, E-mail: mathanranjitha@gmail.com [SRM Research Institute, SRM University, Kattankulathur, Tamil Nadu - 603203 (India); P, Sabarikirishwaran [Department of Physics and Nanotechnology, SRM University, Kattankulathur, Tamil Nadu - 603203 (India)

    2015-06-24

    Using dispersion corrected density functional theory (DFT+D), the interaction of Vanadium adatom and cluster with divacancy (555-777) defective graphene sheet has been studied elaborately. We explore the prospect of hydrogen storage on V{sub 4} cluster adsorbed divacancy graphene system. It has been observed that V{sub 4} cluster (acting as a catalyst) can dissociate the H{sub 2} molecule into H atoms with very low barrier energy. We introduce the spillover of the atomic hydrogen throughout the surface via external mediator gallane (GaH{sub 3}) to form a hydrogenated system.

  7. Reference Concepts for a Space-Based Hydrogen-Oxygen Combustion, Turboalternator, Burst Power System

    National Research Council Canada - National Science Library

    Edenburn, Michael

    1990-01-01

    This report describes reference concepts for a hydrogen-oxygen combustion, turboalternator power system that supplies power during battle engagement to a space-based, ballistic missile defense platform...

  8. Safety and operations of hydrogen fuel infrastructure in northern climates : a collaborative complex systems approach.

    Science.gov (United States)

    2010-10-07

    "This project examined the safety and operation of hydrogen (H2) fueling system infrastructure in : northern climates. A multidisciplinary team lead by the University of Vermont (UVM), : combined with investigators from Zhejiang and Tsinghua Universi...

  9. Experimental evaluation of improved dual temperature hydrogen isotopic exchange reaction system

    International Nuclear Information System (INIS)

    Asakura, Yamato; Uchida, Shunsuke

    1984-01-01

    A proposed dual temperature hydrogen isotopic exchange reaction system between water and hydrogen gas is evaluated experimentally. The proposed system is composed of low temperature co-current reactors for reaction between water mists and hydrogen gas and high temperature co-current reactors for reaction between water vapor and hydrogen gas. Thus, operation is possible under atmospheric pressure with high reaction efficiency. Using the pilot test system which is composed of ten low temperature (30 0 C) reaction units and ten high temperature (200 0 C) reaction units, an experimental separation of deuterium from light water is carried out. The enrichment factor under steady state conditions, its dependency on operating time, and the reaction period necessary to obtain the steady state enrichment factor are determined experimentally and compared with calculations. It is shown that separation ability in a multistage reaction system can be estimated by numerical calculation using actual reaction efficiency in a unit reactor. (author)

  10. Long term hydrogen production potential of concentrated photovoltaic (CPV) system in tropical weather of Singapore

    KAUST Repository

    Burhan, Muhammad; Chua, Kian Jon Ernest; Ng, Kim Choon

    2016-01-01

    far, only conventional flat plate PV systems are being used for almost all of the commercial applications. However, most of the studies have only shown the maximum efficiency of hydrogen production using CPV. In actual field conditions, the performance

  11. Integrated Microchannel Reformer/Hydrogen Purifier for Fuel Cell Power Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Makel Engineering, Inc. (MEI) and Colorado School of Mines (CSM) propose to develop an integrated hydrogen generator and purifier system for conversion of in-situ...

  12. OH stretching frequencies in systems with intramolecular hydrogen bonds

    DEFF Research Database (Denmark)

    Spanget-Larsen, Jens; Hansen, Bjarke Knud Vilster; Hansen, Poul Erik

    2011-01-01

    OH stretching wavenumbers were investigated for 30 species with intramolecularly hydrogen bonded hydroxyl groups, covering the range from 3600 to ca. 1900 cm-1. Theoretical wavenumbers were predicted with B3LYP/6-31G(d) density functional theory using the standard harmonic approximation, as well...

  13. Safety assessment of VHTR hydrogen production system against fire, explosion and acute toxicity

    International Nuclear Information System (INIS)

    Murakami, Tomoyuki; Nishihara, Tetsuo; Kunitomi, Kazuhiko

    2008-01-01

    The Japan Atomic Energy Agency has been developing a nuclear hydrogen production system by using heat from the Very High Temperature Reactor (VHTR). This system will handle a large amount of combustible gas and toxic gas. The risk from fire, explosion and acute toxic exposure caused by an accident involving chemical material release in a hydrogen production system is assessed. It is important to ensure the safety of the nuclear plant, and the risks for public health should be sufficiently small. This report provides the basic policy for the safety evaluation in cases of accident involving fire, explosion and toxic material release in a hydrogen production system. Preliminary safety analysis of a commercial-sized VHTR hydrogen production system, GTHTR300C, is performed. This analysis provides us with useful information on the separation distance between a nuclear plant and a hydrogen production system and a prospect that an accident in a hydrogen production system does not significantly increase the risks of the public. (author)

  14. The Origin of the Non-Additivity in Resonance-Assisted Hydrogen Bond Systems.

    Science.gov (United States)

    Lin, Xuhui; Zhang, Huaiyu; Jiang, Xiaoyu; Wu, Wei; Mo, Yirong

    2017-11-09

    The concept of resonance-assisted hydrogen bond (RAHB) has been widely accepted, and its impact on structures and energetics can be best studied computationally using the block-localized wave function (BLW) method, which is a variant of ab initio valence bond (VB) theory and able to derive strictly electron-localized structures self-consistently. In this work, we use the BLW method to examine a few molecules that result from the merging of two malonaldehyde molecules. As each of these molecules contains two hydrogen bonds, these intramolecular hydrogen bonds may be cooperative or anticooperative, depended on their relative orientations, and compared with the hydrogen bond in malonaldehyde. Apart from quantitatively confirming the concept of RAHB, the comparison of the computations with and without π resonance shows that both σ-framework and π-resonance contribute to the nonadditivity in these RAHB systems with multiple hydrogen bonds.

  15. Feasibility of high-speed power line carrier system to Japanese overhead low voltage distribution lines; Teiatsu haidensen hanso no kosokuka no kanosei (hanso sningo denpa purogram no kanosei)

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, T.; Takeshita, K.; Ishino, R.

    2000-06-01

    The high-speed distribution line carrier systems on underground distribution lines are being developed in Germany. To estimate these systems on Japanese overhead low voltage distribution lines, the Carrier Propagation Program has been developed and applicability of OFDM system was roughly estimated. 1. Carrier Propagation Program Carrier Propagation Program that calculates the carrier propagation characteristics of any line structure was developed. 2. Carrier propagation characteristics Carrier propagation characteristics on typical Japanese overhead low voltage distribution lines were calculated 3.Rough estimation of OFDM system Electric fields caused by carrier at near point were calculated on the basis on carrier propagation characteristics. Results of rough estimation are as follows: - Electric field caused by carrier of more than 2Mbps system exceeds the value of the regulation. (author)

  16. Analytical Investigations on Carrier Phase Recovery in Dispersion-Unmanaged n-PSK Coherent Optical Communication Systems

    Directory of Open Access Journals (Sweden)

    Tianhua Xu

    2016-09-01

    Full Text Available Using coherent optical detection and digital signal processing, laser phase noise and equalization enhanced phase noise can be effectively mitigated using the feed-forward and feed-back carrier phase recovery approaches. In this paper, theoretical analyses of feed-back and feed-forward carrier phase recovery methods have been carried out in the long-haul high-speed n-level phase shift keying (n-PSK optical fiber communication systems, involving a one-tap normalized least-mean-square (LMS algorithm, a block-wise average algorithm, and a Viterbi-Viterbi algorithm. The analytical expressions for evaluating the estimated carrier phase and for predicting the bit-error-rate (BER performance (such as the BER floors have been presented and discussed in the n-PSK coherent optical transmission systems by considering both the laser phase noise and the equalization enhanced phase noise. The results indicate that the Viterbi-Viterbi carrier phase recovery algorithm outperforms the one-tap normalized LMS and the block-wise average algorithms for small phase noise variance (or effective phase noise variance, while the one-tap normalized LMS algorithm shows a better performance than the other two algorithms for large phase noise variance (or effective phase noise variance. In addition, the one-tap normalized LMS algorithm is more sensitive to the level of modulation formats.

  17. Application of CFRP with High Hydrogen Gas Barrier Characteristics to Fuel Tanks of Space Transportation System

    Science.gov (United States)

    Yonemoto, Koichi; Yamamoto, Yuta; Okuyama, Keiichi; Ebina, Takeo

    In the future, carbon fiber reinforced plastics (CFRPs) with high hydrogen gas barrier performance will find wide applications in all industrial hydrogen tanks that aim at weight reduction; the use of such materials will be preferred to the use of conventional metallic materials such as stainless steel or aluminum. The hydrogen gas barrier performance of CFRP will become an important issue with the introduction of hydrogen-fuel aircraft. It will also play an important role in realizing fully reusable space transportation system that will have high specific tensile CFRP structures. Such materials are also required for the manufacture of high-pressure hydrogen gas vessels for use in the fuel cell systems of automobiles. This paper introduces a new composite concept that can be used to realize CFRPs with high hydrogen gas barrier performance for applications in the cryogenic tanks of fully reusable space transportation system by the incorporation of a nonmetallic crystal layer, which is actually a dense and highly oriented clay crystal laminate. The preliminary test results show that the hydrogen gas barrier characteristics of this material after cryogenic heat shocks and cyclic loads are still better than those of other polymer materials by approximately two orders of magnitude.

  18. Study on the hydrogen demand in China based on system dynamics model

    International Nuclear Information System (INIS)

    Ma, Tao; Ji, Jie; Chen, Ming-qi

    2010-01-01

    Reasonable estimation of hydrogen energy and other renewable energy demand of China's medium and long-term energy is of great significance for China's medium and long-term energy plan. Therefore, based on both China's future economic development and relative economic theory and system dynamics theory, this article analyzes qualitatively the internal factors and external factors of hydrogen energy demand system, and makes the state high and low two assumptions about China's medium and long-term hydrogen demand according to the different speed of China's economic development. After the system dynamic model setting up export and operation, the output shows the data changes of the total hydrogen demand and the four kinds of hydrogen demand. According to the analysis of the output, two conclusions are concluded: The secondary industry, not the tertiary industry (mainly the transportation), should be firstly satisfied by the hydrogen R and D and support of Government policy. Change of Chinese hydrogen demand scale, on basis of its economic growth, can not be effective explained through Chinese economic growth rate, and other influencing factor and mechanism should be probed deeply. (author)

  19. Hydrogen energy - Abundant, efficient, clean: A debate over the energy-system-of-change

    Energy Technology Data Exchange (ETDEWEB)

    Winter, Carl-Jochen [International Association for Hydrogen Energy (IAHE), c/o ENERGON Carl-Jochen Winter e.K., Obere St.-Leonhardstr. 9, 88662 Ueberlingen (Germany)

    2009-07-15

    Both secondary energies, electricity and hydrogen, have much in common: they are technology driven; both are produced from any available primary energy; once produced both are environmentally and climatically clean over the entire length of their respective conversion chains, from production to utilization; they are electrochemically interchangeable via electrolyses and fuel cells; both rely on each other, e.g., when electrolyzers and liquefiers need electricity or when electricity-providing low temperature fuel cells need hydrogen; in cases of secondary energy transport over longer distances they compete with each other; in combined fossil fuel cycles both hydrogen and electricity are produced in parallel exergetically highly efficiently; hydrogen in addition to electricity helps exergizing the energy system and, thus, maximizing the available technical work. There are dissimilarities, too: electricity transports information, hydrogen does not; hydrogen stores and transports energy, electricity does not (in macroeconomic terms). The most obvious dissimilarity is their market presence, both in capacities and in availability: Electricity is globally ubiquitous (almost), whilst hydrogen energy is still used in only selected industrial areas and in much smaller capacities. The article describes in 15 chapters, 33 figures, 3 tables, and 2 Annexes the up-and-coming hydrogen energy economy, its environmental and climatic relevance, its exergizing influence on the energy system, its effect on decarbonizing fossil fueled power plants, the introduction of the novel non-heat-engine-related electrochemical energy converter fuel cell in portable electronics, in stationary and mobile applications. Hydrogen guarantees environmentally and climatically clean transportation on land, in air and space, and at sea. Hydrogen facilitates the electrification of vehicles with practically no range limits. (author)

  20. Cost estimation of hydrogen and DME produced by nuclear heat utilization system II

    International Nuclear Information System (INIS)

    Shiina, Yasuaki; Nishihara, Tetsuo

    2004-09-01

    Utilization and production of hydrogen has been studied in order to spread utilization of the hydrogen energy in 2020 or 2030. It will take, however, many years for the hydrogen energy to be used very easily like gasoline, diesel oil and city gas in the world. During the periods, low CO 2 release liquid fuels would be used together with hydrogen. Recently, di-methyl-ether (DME). has been noticed as one of the substitute liquid fuels of petroleum. Such liquid fuels can be produced from the mixed gas such as hydrogen and carbon oxide which are produced from natural gas by steam reforming. Therefore, the system would become one of the candidates of future system of nuclear heat utilization. Following the study in 2002, we performed economic evaluation of the hydrogen and DME production by nuclear heat utilization plant where heat generated by HTGR is completely consumed for the production. The results show that hydrogen price produced by nuclear was about 17% cheaper than the commercial price by increase in recovery rate of high purity hydrogen with increased in PSA process. Price of DME in indirect method produced by nuclear heat was also about 17% cheaper than the commercial price by producing high purity hydrogen in the DME producing process. As for the DME, since price of DME produced near oil land in petroleum exporting countries is cheaper than production in Japan, production of DME by nuclear heat in Japan has disadvantage economically in this time. Trial study to estimate DME price produced by direct method was performed. From the present estimation, utilization of nuclear heat for the production of hydrogen would be more effective with coupled consideration of reduction effect of CO 2 release. (author)

  1. Universally applicable design concept of stably controlling an HTGR-hydrogen production system

    International Nuclear Information System (INIS)

    Hada, Kazuhiko; Shibata, Taiju; Nishihara, Tetsuo; Shiozawa, Shusaku

    1996-01-01

    An HTGR-hydrogen production system should be designed to have stable controllability because of a large difference in thermal dynamics between reactor and hydrogen production system and such a control design concept should be universally applicable to a variety of hydrogen production processes by the use of nuclear heat from HTGR. A transient response analysis of an HTGR-steam reforming hydrogen production system showed that a steam generator installed in a helium circuit for cooling the nuclear reactor provides stable controllability of the total system, resulting in avoiding a reactor scram. A survey of control design-related characteristics among several hydrogen production processes revealed the similarity of endothermic chemical reactions by the use of high temperature heat and that steam is required as a reactant of the endothermic reaction or for preheating a reactant. Based on these findings, a system design concept with stable controllability and universal applicability was proposed to install a steam generator as a downstream cooler of an endothermic reactor in the helium circuit of an HTGR-hydrogen production system. (author)

  2. Research and development program of hydrogen production system with high temperature gas-cooled reactor

    International Nuclear Information System (INIS)

    Miyamoto, Y.; Shiozawa, S.; Ogawa, M.; Inagaki, Y.; Nishihara, T.; Shimizu, S.

    2000-01-01

    Japan Atomic Energy Research Institute (JAERI) has been developing a hydrogen production system with a high temperature gas-cooled reactor (HTGR). While the HTGR hydrogen production system has the following advantages compared with a fossil-fired hydrogen production system; low operation cost (economical fuel cost), low CO 2 emission and saving of fossil fuel by use of nuclear heat, it requires some items to be solved as follows; cost reduction of facility such as a reactor, coolant circulation system and so on, development of control and safety technologies. As for the control and safety technologies, JAERI plans demonstration test with hydrogen production system by steam reforming of methane coupling to 30 Wt HTGR, named high temperature engineering test reactor (HTTR). Prior to the demonstration test, a 1/30-scale out-of-pile test facility is in construction for safety review and detailed design of the HTTR hydrogen production system. Also, design study will start for reduction of facility cost. Moreover, basic study on hydrogen production process without CO 2 emission is in progress by thermochemical water splitting. (orig.)

  3. Preparation of open porous polycaprolactone microspheres and their applications as effective cell carriers in hydrogel system

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Qingchun [Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering (China); Tan, Ke; Ye, Zhaoyang [State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai, 200237 China (China); Zhang, Yan, E-mail: zhang_yan@ecust.edu.cn [Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering (China); Tan, Wensong [State Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, Shanghai, 200237 China (China); Lang, Meidong, E-mail: mdlang@ecust.edu.cn [Key Laboratory for Ultrafine Materials of Ministry of Education, School of Materials Science and Engineering (China)

    2012-12-01

    Common hydrogel, composed of synthetic polymers or natural polysaccharides could not support the adhesion of anchorage-dependent cells due to the lack of cell affinitive interface and high cell constraint. The use of porous polyester microspheres as cell-carriers and introduction of cell-loaded microspheres into the hydrogel system might overcome the problem. However, the preparation of the open porous microsphere especially using polycaprolactone (PCL) has been rarely reported. Here, the open porous PCL microspheres were fabricated via the combined emulsion/solvent evaporation and particle leaching method. The microspheres exhibited porous surface and inter-connective pore structure. Additionally, the pore structure could be easily controlled by adjusting the processing parameters. The surface pore size could be altered from 20 {mu}m to 80 {mu}m and the internal porosities were varied from 30% to 70%. The obtained microspheres were evaluated to delivery mesenchymal stem cells (MSCs) and showed the improved cell adhesion and growth when compared with the non-porous microspheres. Then, the MSCs loaded microspheres were introduced into agarose hydrogel. MSCs remained alive and sustained proliferation in microsphere/agarose composite in 5-day incubation while a decrement of MSCs viabilities was found in agarose hydrogel without microspheres. The results indicated that the microsphere/hydrogel composite had a great potential in cell therapy and injectable system for tissue regeneration. Highlights: Black-Right-Pointing-Pointer The open porous polycaprolactone microspheres were fabricated using paraffin as a porogen. Black-Right-Pointing-Pointer The microspheres exhibited porous surface and inter-connective pore structure. Black-Right-Pointing-Pointer The surface and internal pore size and porosity of microsphere could be controlled. Black-Right-Pointing-Pointer The porous microspheres exhibited an improved cell adhesion and proliferation. Black

  4. Hydrogen from Water in a Novel Recombinant Cyanobacterial System

    Energy Technology Data Exchange (ETDEWEB)

    Weyman, Philip D [J. Craig Venter Institute; Smith, Hamillton O.

    2014-12-03

    Photobiological processes are attractive routes to renewable H2 production. With the input of solar energy, photosynthetic microbes such as cyanobacteria and green algae carry out oxygenic photosynthesis, using sunlight energy to extract protons and high energy electrons from water. These protons and high energy electrons can be fed to a hydrogenase system yielding H2. However, most hydrogen-evolving hydrogenases are inhibited by O2, which is an inherent byproduct of oxygenic photosynthesis. The rate of H2 production is thus limited. Certain photosynthetic bacteria are reported to have an O2-tolerant evolving hydrogenase, yet these microbes do not split water, and require other more expensive feedstocks. To overcome these difficulties, the goal of this work has been to construct novel microbial hybrids by genetically transferring O2-tolerant hydrogenases from other bacteria into a class of photosynthetic bacteria called cyanobacteria. These hybrid organisms will use the photosynthetic machinery of the cyanobacterial hosts to perform the water-oxidation reaction with the input of solar energy, and couple the resulting protons and high energy electrons to the O2-tolerant bacterial hydrogenase, all within the same microbe (Fig. 1). The ultimate goal of this work has been to overcome the sensitivity of the hydrogenase enzyme to O2 and address one of the key technological hurdles to cost-effective photobiological H2 production which currently limits the production of hydrogen in algal systems. In pursuit of this goal, work on this project has successfully completed many subtasks leading to a greatly increased understanding of the complicated [NiFe]-hydrogenase enzymes. At the beginning of this project, [NiFe] hydrogenases had never been successfully moved across wide species barriers and had never been heterologously expressed in cyanobacteria. Furthermore, the idea that whole, functional genes could be extracted from complicated, mixed-sequence meta-genomes was not

  5. Alkaline sodium borohydride gel as a hydrogen source for PEMFC or an energy carrier for NaBH{sub 4}-air battery

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B.H. [Department of Materials and Engineering, Zhejiang University (China); Li, Z.P.; Chen, L.L. [Department of Chemical and Biochemical Engineering, Zhejiang University, Hangzhou 310027 (China)

    2008-05-15

    In this preliminary study, we tried to use sodium polyacrylate as the super absorbent polymer to form alkaline NaBH{sub 4} gel and explored its possibilities for borohydride hydrolysis and borohydride electro-oxidation. It was found that the absorption capacity of sodium polyacrylate decreased with increasing NaBH{sub 4} concentration. The formed gel was rather stable in the sealed vessel but tended to slowly decompose in open air. Hydrogen generation from the gel was carried out using CoCl{sub 2} catalyst precursor solutions. Hydrogen generation rate from the alkaline NaBH{sub 4} gel was found to be higher and impurities in hydrogen were less than that from the alkaline NaBH{sub 4} solution. The NaBH{sub 4} gel also successfully powered a NaBH{sub 4}-air battery. (author)

  6. Alkaline sodium borohydride gel as a hydrogen source for PEMFC or an energy carrier for NaBH 4-air battery

    Science.gov (United States)

    Liu, B. H.; Li, Z. P.; Chen, L. L.

    In this preliminary study, we tried to use sodium polyacrylate as the super absorbent polymer to form alkaline NaBH 4 gel and explored its possibilities for borohydride hydrolysis and borohydride electro-oxidation. It was found that the absorption capacity of sodium polyacrylate decreased with increasing NaBH 4 concentration. The formed gel was rather stable in the sealed vessel but tended to slowly decompose in open air. Hydrogen generation from the gel was carried out using CoCl 2 catalyst precursor solutions. Hydrogen generation rate from the alkaline NaBH 4 gel was found to be higher and impurities in hydrogen were less than that from the alkaline NaBH 4 solution. The NaBH 4 gel also successfully powered a NaBH 4-air battery.

  7. Embedded system based on PWM control of hydrogen generator with SEPIC converter

    Science.gov (United States)

    Fall, Cheikh; Setiawan, Eko; Habibi, Muhammad Afnan; Hodaka, Ichijo

    2017-09-01

    The objective of this paper is to design and to produce a micro electrical plant system based on fuel cell for teaching material-embedded systems in technical vocational training center. Based on this, the student can experience generating hydrogen by fuel cells, controlling the rate of hydrogen generation by the duty ration of single-ended primary-inductor converter(SEPIC), drawing the curve rate of hydrogen to duty ratio, generating electrical power by using hydrogen, and calculating the fuel cell efficiency when it is used as electrical energy generator. This project is of great importance insofar as students will need to acquire several skills to be able to realize it such as continuous DC DC conversion and the scientific concept behind the converter, the regulation of systems with integral proportional controllers, the installation of photovoltaic cells, the use of high-tech sensors, microcontroller programming, object-oriented programming, mastery of the fuel cell syste

  8. High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Daniel A. Mosher; Xia Tang; Ronald J. Brown; Sarah Arsenault; Salvatore Saitta; Bruce L. Laube; Robert H. Dold; Donald L. Anton

    2007-07-27

    This final report describes the motivations, activities and results of the hydrogen storage independent project "High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides" performed by the United Technologies Research Center under the Department of Energy Hydrogen Program, contract # DE-FC36-02AL67610. The objectives of the project were to identify and address the key systems technologies associated with applying complex hydride materials, particularly ones which differ from those for conventional metal hydride based storage. This involved the design, fabrication and testing of two prototype systems based on the hydrogen storage material NaAlH4. Safety testing, catalysis studies, heat exchanger optimization, reaction kinetics modeling, thermochemical finite element analysis, powder densification development and material neutralization were elements included in the effort.

  9. 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

  10. Feasibility analysis of a hydrogen backup power system for Russian telecom market

    Science.gov (United States)

    Borzenko, V. I.; Dunikov, D. O.

    2017-11-01

    We performed feasibility analysis of 10 kW hydrogen backup power system (H2BS) consisting of a water electrolyzer, a metal hydride hydrogen storage and a fuel cell. Capital investments in H2BS are mostly determined by the costs of the PEM electrolyzer, the fuel cell and solid state hydrogen storage materials, for single unit or small series manufacture the cost of AB5-type intermetallic compound can reach 50% of total system cost. Today the capital investments in H2BS are 3 times higher than in conventional lead-acid system of the same capacity. Wide distribution of fuel cell hydrogen vehicles, development of hydrogen infrastructure, and mass production of hydrogen power systems will for sure lower capital investments in fuel cell backup power. Operational expenditures for H2BS is only 15% from the expenditures for lead acid systems, and after 4-5 years of exploitation the total cost of ownership will become lower than for batteries.

  11. 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.

  12. Lock threshold deterioration induced by antenna vibration and signal coupling effects in hypersonic vehicle carrier tracking system of Ka band

    Directory of Open Access Journals (Sweden)

    Congying ZHU

    2018-04-01

    Full Text Available The envelope of a hypersonic vehicle is affected by severe fluctuating pressure, which causes the airborne antenna to vibrate slightly. This vibration mixes with the transmitted signals and thus introduces additional multiplicative phase noise. Antenna vibration and signal coupling effects as well as their influence on the lock threshold of the hypersonic vehicle carrier tracking system of the Ka band are investigated in this study. A vibration model is initially established to obtain phase noise in consideration of the inherent relationship between vibration displacement and electromagnetic wavelength. An analytical model of the Phase-Locked Loop (PLL, which is widely used in carrier tracking systems, is established. The coupling effects on carrier tracking performance are investigated and quantitatively analyzed by imposing the multiplicative phase noise on the PLL model. Simulation results show that the phase noise presents a Gaussian distribution and is similar to vibration displacement variation. A large standard deviation in vibration displacement exerts a significant effect on the lock threshold. A critical standard deviation is observed in the PLL of Binary Phase Shift Keying (BPSK and Quadrature Phase Shift Keying (QPSK signals. The effect on QPSK signals is more severe than that on BPSK signals. The maximum tolerable standard deviations normalized by the wavelength of the carrier are 0.04 and 0.02 for BPSK and QPSK signals, respectively. With these critical standard deviations, lock thresholds are increased from −12 and −4 dB to 3 and −2 dB, respectively. Keywords: Antenna vibration, Carrier tracking performance, Lock threshold, Phase locked loop, Tracking Telemetry and Command (TT&C signals

  13. Single Carrier Cyclic Prefix-Assisted CDMA System with Frequency Domain Equalization for High Data Rate Transmission

    Directory of Open Access Journals (Sweden)

    Madhukumar A. S.

    2004-01-01

    Full Text Available Multiple-access interference and interfinger interference limit the capacity of conventional single-carrier DS-CDMA systems. Even though multicarrier CDMA posses the advantages of conventional CDMA and OFDM, it suffers from two major implementation difficulties such as peak-to-average power ratio and high sensitivity to frequency offset and RF phase noise. A novel approach based on single-carrier cyclic prefix-assisted CDMA has been proposed to overcome the disadvantages of single-carrier CDMA and multicarrier modulation. The usefulness of the proposed approach for high-speed packet access with simplified channel estimation procedures are investigated in this paper. The paper also proposes a data-dependent pilot structure for the downlink transmission of the proposed system for enhancing pilot-assisted channel estimation in frequency domain. The performance of the proposed pilot structure is compared against the data-independent common pilot structure. The proposed system is extensively simulated for different channel parameters with different channel estimation and equalization methods and the results are compared against conventional multicarrier CDMA systems with identical system specifications.

  14. Fundamental philosophy on the safety design of the HTTR-IS hydrogen production system

    International Nuclear Information System (INIS)

    Ohashi, Kazutaka; Nishihara, Tetsuo; Kunitomi, Kazuhiko

    2007-01-01

    Japan Atomic Energy Agency (JAEA) has been conducting an R and D work on the VHTR reactor system and IS hydrogen production system to realize hydrogen production using nuclear heat. As a part of this activity, JAEA is planning to connect an IS test system to the High Temperature Engineering Test Reactor (HTTR) to demonstrate its technical feasibility. This paper proposes a fundamental philosophy on the safety design of the HTTR-IS hydrogen production system including the methodology to select postulated abnormal events and its event sequences and to define safety functions of the IS system to ensure the reactor safety. Also the measure to clarify the IS system as non-reactor system is proposed. (author)

  15. Hourly energy management for grid-connected wind-hydrogen systems

    International Nuclear Information System (INIS)

    Bernal-Agustin, Jose L.; Dufo-Lopez, Rodolfo

    2008-01-01

    This paper is a complete technical-economic analysis of the hourly energy management of the energy generated in wind-hydrogen systems. Wind power generation depends on the unpredictable nature of the wind. If the wind-power penetration becomes high in the Spanish electrical grid, energy management will be necessary for some wind farms. A method is proposed in this paper to adjust the generation curve to the demand curve, consisting of the generation of hydrogen and storing it in a hydrogen tank during off-peak (low demand) hours, while during the rest of the hours (peak hours, high demand) the stored hydrogen can be used to generate electricity. After revising the results obtained in this paper, for the current values of efficiency of the electricity-hydrogen-electricity conversion (approximately 30%) and due to the high cost of the hydrogen components, for a wind-hydrogen system to be economically viable the price of the sale of the energy generated by the fuel cell would be very high (approximately 171 cEUR/kWh). (author)

  16. Analysis of heat conduction in a drum brake system of the wheeled armored personnel carriers

    Science.gov (United States)

    Puncioiu, A. M.; Truta, M.; Vedinas, I.; Marinescu, M.; Vinturis, V.

    2015-11-01

    This paper is an integrated study performed over the Braking System of the Wheeled Armored Personnel Carriers. It mainly aims to analyze the heat transfer process which is present in almost any industrial and natural process. The vehicle drum brake systems can generate extremely high temperatures under high but short duration braking loads or under relatively light but continuous braking. For the proper conduct of the special vehicles mission in rough terrain, we are talking about, on one hand, the importance of the possibility of immobilization and retaining position and, on the other hand, during the braking process, the importance movement stability and reversibility or reversibility, to an encounter with an obstacle. Heat transfer processes influence the performance of the braking system. In the braking phase, kinetic energy transforms into thermal energy resulting in intense heating and high temperature states of analyzed vehicle wheels. In the present work a finite element model for the temperature distribution in a brake drum is developed, by employing commercial finite element software, ANSYS. These structural and thermal FEA models will simulate entire braking event. The heat generated during braking causes distortion which modifies thermoelastic contact pressure distribution drum-shoe interface. In order to capture the effect of heat, a transient thermal analysis is performed in order to predict the temperature distribution transitional brake components. Drum brakes are checked both mechanical and thermal. These tests aim to establish their sustainability in terms of wear and the variation coefficient of friction between the friction surfaces with increasing temperature. Modeling using simulation programs led eventually to the establishment of actual thermal load of the mechanism of brake components. It was drawn the efficiency characteristic by plotting the coefficient of effectiveness relative to the coefficient of friction shoe-drum. Thus induced

  17. Hydrogen-control systems for severe LWR accident conditions - a state-of-technology report

    International Nuclear Information System (INIS)

    Hilliard, R.K.; Postma, A.K.; Jeppson, D.W.

    1983-03-01

    This report reviews the current state of technology regarding hydrogen safety issues in light water reactor plants. Topics considered in this report relate to control systems and include combustion prevention, controlled combustion, minimization of combustion effects, combination of control concepts, and post-accident disposal. A companion report addresses hydrogen generation, distribution, and combustion. The objectives of the study were to identify the key safety issues related to hydrogen produced under severe accident conditions, to describe the state of technology for each issue, and to point out ongoing programs aimed at resolving the open issues

  18. Texture-geometric deformational effects in some metal-hydrogen systems

    International Nuclear Information System (INIS)

    Spivak, L.V.; Kats, M.Ya.

    1992-01-01

    Possible deformation effects were studied in vanadium, tantalum, niobium, palladium and iron which occurred during electrolytic hydrogenation of specimens preliminarily deformed by torsion and then annealed. Noticeable texture-geometric effects were observed and related to the system tendency to enhance the degree of specimen form symmetry during hydrogenation. The latter was an off-beat realization of Le-Chatelier principle. It was assumed that the nature of deformation effects was connected with one of minimization channels for overall elastic stress fields in metals being hydrogenated. Some distinction was revealed in behaviour of 5a group metal, palladium and iron

  19. Detection of interstellar pick-up hydrogen in the solar system

    Science.gov (United States)

    Gloeckler, G.; Geiss, J.; Balsiger, H.; Fisk, L. A.; Galvin, A. B.; Ipavich, F. M.; Ogilvie, K. W.; Von Steiger, R.; Wilken, B.

    1993-01-01

    Interstellar hydrogen ionized primarily by the solar wind has been detected by the Solar Wind Ion Composition Spectrometer instrument on the Ulysses spacecraft at a distance of 4.8 AUs from the sun. This 'pick-up' hydrogen is identified by its distinct velocity distribution function, which drops abruptly at twice the local solar wind speed. From the measured fluxes of pick-up protons and singly charged helium, the number densities of neutral hydrogen and helium in the distant regions of the solar system are estimated to be 0.077 +/- 0.015 and 0.013 +/- 0.003 per cu cm, respectively.

  20. Recyclable hydrogen storage system composed of ammonia and alkali metal hydride

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Hikaru [Department of Quantum Matter, AdSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530 (Japan); Miyaoka, Hiroki; Hino, Satoshi [Institute for Advanced Materials Research, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530 (Japan); Nakanishi, Haruyuki [Higashi-Fuji Technical Center, Toyota Motor Corporation, 1200 Misyuku, Susono, Shizuoka 410-1193 (Japan); Ichikawa, Takayuki; Kojima, Yoshitsugu [Department of Quantum Matter, AdSM, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530 (Japan); Institute for Advanced Materials Research, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8530 (Japan)

    2009-12-15

    Ammonia (NH{sub 3}) reacts with alkali metal hydrides MH (M = Li, Na, and K) in an exothermic reaction to release hydrogen (H{sub 2}) at room temperature, resulting that alkali metal amides (MNH{sub 2}) which are formed as by-products. In this work, hydrogen desorption properties of these systems and the condition for the recycle from MNH{sub 2} back to MH were investigated systematically. For the hydrogen desorption reaction, the reactivities of MH with NH{sub 3} were better following the atomic number of M on the periodic table, Li < Na < K. It was confirmed that the hydrogen absorption reaction of all the systems proceeded under 0.5 MPa of H{sub 2} flow condition below 300 C. (author)

  1. Hydrogen generation systems and methods utilizing sodium silicide and sodium silica gel materials

    Energy Technology Data Exchange (ETDEWEB)

    Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael

    2017-12-19

    Systems, devices, and methods combine thermally stable reactant materials and aqueous solutions to generate hydrogen and a non-toxic liquid by-product. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Springs and other pressurization mechanisms pressurize and deliver an aqueous solution to the reaction. A check valve and other pressure regulation mechanisms regulate the pressure of the aqueous solution delivered to the reactant fuel material in the reactor based upon characteristics of the pressurization mechanisms and can regulate the pressure of the delivered aqueous solution as a steady decay associated with the pressurization force. The pressure regulation mechanism can also prevent hydrogen gas from deflecting the pressure regulation mechanism.

  2. Relations between oxygen and hydrogen generated by radiolysis in the systems of a CANDU 600

    International Nuclear Information System (INIS)

    Romano, Christian; Chocron, Mauricio; Urrutia, Guillermo

    1999-01-01

    The water that constitutes the coolant of the primary heat transport system, the moderator and the liquid control zones, decomposed under radiation producing as stable products oxygen, hydrogen and hydrogen peroxide throughout a complex mechanisms of radiolysis that involves ions and free radicals. These compound formed in different proportions alters the chemical control established for each system which purpose is to minimize the corrosion of the structural materials. In the present paper have been presented results of the modelling of the mentioned processes and it has been found that in the absence of a vapor phase, a relatively low concentration of hydrogen added to the water would be sufficient to control the formation of oxygen and hydrogen peroxide. The last species however, would remain in relatively high values inside a coolant fuel channel in the reactor core. (author)

  3. Hydrogen production by high-temperature gas-cooled reactor. Conceptual design of advanced process heat exchangers of the HTTR-IS hydrogen production system

    International Nuclear Information System (INIS)

    Sakaba, Nariaki; Ohashi, Hirofumi; Sato, Hiroyuki; Hara, Teruo; Kato, Ryoma; Kunitomi, Kazuhiko

    2008-01-01

    Nuclear hydrogen production is necessary in an anticipated hydrogen society that demands a massive quantity of hydrogen without economic disadvantage. Japan Atomic Energy Agency (JAEA) has launched the conceptual design study of a hydrogen production system with a near-term plan to connect it to Japan's first high-temperature gas-cooled reactor HTTR. The candidate hydrogen production system is based on the thermochemical water-splitting iodine sulphur (IS) process.The heat of 10 MWth at approximately 900degC, which can be provided by the secondary helium from the intermediate heat exchanger of the HTTR, is the energy input to the hydrogen production system. In this paper, we describe the recent progresses made in the conceptual design of advanced process heat exchangers of the HTTR-IS hydrogen production system. A new concept of sulphuric acid decomposer is proposed. This involves the integration of three separate functions of sulphuric acid decomposer, sulphur trioxide decomposer, and process heat exchanger. A new mixer-settler type of Bunsen reactor is also designed. This integrates three separate functions of Bunsen reactor, phase separator, and pump. The new concepts are expected to result in improved economics through construction and operation cost reductions because the number of process equipment and complicated connections between the equipment has been substantially reduced. (author)

  4. 1 kWe sodium borohydride hydrogen generation system Part II: Reactor modeling

    OpenAIRE

    Zhang, Jinsong; Zheng, Yuan; Gore, Jay P; Mudawar, Issam; Fisher, Timothy

    2007-01-01

    Sodium borohydride (NaBH4) hydrogen storage systems offer many advantages for hydrogen storage applications. The physical processes inside a NaBH4 packed bed reactor involve multi-component and multi-phase flow and multi-mode heat and mass transfer. These processes are also coupled with reaction kinetics. To guide reactor design and optimization, a reactor model involving all of these processes is desired. A onedimensional numerical model in conjunction with the assumption of homogeneous cata...

  5. Sizing and economic analysis of stand alone photovoltaic system with hydrogen storage

    Science.gov (United States)

    Nordin, N. D.; Rahman, H. A.

    2017-11-01

    This paper proposes a design steps in sizing of standalone photovoltaic system with hydrogen storage using intuitive method. The main advantage of this method is it uses a direct mathematical approach to find system’s size based on daily load consumption and average irradiation data. The keys of system design are to satisfy a pre-determined load requirement and maintain hydrogen storage’s state of charge during low solar irradiation period. To test the effectiveness of the proposed method, a case study is conducted using Kuala Lumpur’s generated meteorological data and rural area’s typical daily load profile of 2.215 kWh. In addition, an economic analysis is performed to appraise the proposed system feasibility. The finding shows that the levelized cost of energy for proposed system is RM 1.98 kWh. However, based on sizing results obtained using a published method with AGM battery as back-up supply, the system cost is lower and more economically viable. The feasibility of PV system with hydrogen storage can be improved if the efficiency of hydrogen storage technologies significantly increases in the future. Hence, a sensitivity analysis is performed to verify the effect of electrolyzer and fuel cell efficiencies towards levelized cost of energy. Efficiencies of electrolyzer and fuel cell available in current market are validated using laboratory’s experimental data. This finding is needed to envisage the applicability of photovoltaic system with hydrogen storage as a future power supply source in Malaysia.

  6. Infra-red spectra of systems containing hydrogen-bonds; Spectres dans l'infrarouge de corps a liaison hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Marechal, Y [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1969-07-01

    A new theory of the infrared spectra of H-bonded systems is presented, which analyses the different stretching motions in an X-H...Y bond, and studies the validity of their separation. We attribute the structure in the spectra of H-bond stretching motions to the anharmonic coupling of the modes X-H...Y with the modes X-H...H. Starting with the hypothesis that the X-H...Y motion is harmonic, but depends parametrically upon the X...Y distance, and taking into account the interaction between different H-bonds, we have been able to simulate quantitatively (intensity and position) the I.R. spectra of species such as imidazole and acetic acid dimers, which are the experimentally best resolved spectra. The isotope effect (substitution of H by D) is explained quite naturally, and the experimental spectrum of deuterated species is simulated quantitatively, without introducing any other hypothesis; this fact gives us a positive test for the validity of our theory. We have extended those previous considerations to the case of H-bonded crystals, in view of a future reconstitution of their I.R. spectra. The physical meaning of our theory is quite different to most of the previously proposed theories, which have not been confirmed quantitatively, to the best of our knowledge. Those theories did not take into account the interactions between different H-bonds. Thus our quantitative simulation of complex spectra of imidazole and acetic acid, together with the correct prediction of the isotope effect, help us thinking that the proposed mechanism is responsible for the different stretching motions in H-bonded systems. (author) [French] Nous exposons une nouvelle theorie des spectres infra-rouge de la liaison hydrogene, basee sur l'analyse des mouvements d'elongation des atomes d'une liaison X-H...Y, et nous recherchons les conditions de la separabilite de ces differents mouvements. L'origine de la structure des spectres d'elongation de l'hydrogene est attribuee au couplage des modes

  7. Separation of gaseous hydrogen from a water-hydrogen mixture in a fuel cell power system operating in a weightless environment

    Science.gov (United States)

    Romanowski, William E. (Inventor); Suljak, George T. (Inventor)

    1989-01-01

    A fuel cell power system for use in a weightless environment, such as in space, includes a device for removing water from a water-hydrogen mixture condensed from the exhaust from the fuel cell power section of the system. Water is removed from the mixture in a centrifugal separator, and is fed into a holding, pressure operated water discharge valve via a Pitot tube. Entrained nondissolved hydrogen is removed from the Pitot tube by a bleed orifice in the Pitot tube before the water reaches the water discharge valve. Water discharged from the valve thus has a substantially reduced hydrogen content.

  8. Consideration on developing of leaked inflammable gas detection system for HTGR hydrogen production system

    International Nuclear Information System (INIS)

    Nishihara, Tetsuo; Nakamura, Masashi

    1999-09-01

    One of most important safety design issues for High Temperature Gas-cooled Reactor (HTGR) - Hydrogen Production System (HTGR-HPS) is to ensure reactor safety against fire and explosion at the hydrogen production plant. The inflammable gas mixture in the HTGR-HPS does not use oxygen in any condition and are kept in high pressure in the normal operation. The piping system and/or heat transfer tubes which have the potential possibility of combustible materials ingress into the Reactor Building (R/B) due to the failure are designed to prevent the failure against any events. Then, it is not necessary to consider their self-combustion in vessels nor leakage in the R/B. The only one case which we must consider is the ex-building fire or explosion caused by their leakage from piping or vessel. And it is important to mitigate their effects by means of early detection of gas leakage. We investigated our domestic standards on gas detection, applications of gas detectors, their detection principles, performance, sensitivity, reliability, their technical trends, and so on. We proposed three gas detection systems which may be applied in HTGR-HPS. The first one is the universal solid sensor system; it may be applied when there is no necessity to request their safety credits. The second is the combination of the improved solid sensor system and enhanced beam detector system; it may be applied when it is necessary to request their safety credit. And the third is the combination of the universal solid sensor system and the existing beam detector system; it may be applied when the plant owner request higher detector sensitivity than usual, from the view point of public acceptance, though there is not necessity to request their safety credits. To reduce the plant cost by refusing of safety credits to the gas leakage detection system, we proposed that the equipment required to isolate from others should be installed in the inertrized compartments. (author)

  9. Single-cell-based system to monitor carrier driven cellular auxin homeostasis

    Czech Academy of Sciences Publication Activity Database

    Barbez, E.; Laňková, Martina; Pařezová, Markéta; Maizel, A.; Zažímalová, Eva; Petrášek, Jan; Friml, J.; Kleine-Vehn, J.

    2013-01-01

    Roč. 13, FEB 4 (2013) ISSN 1471-2229 R&D Projects: GA ČR(CZ) GAP305/11/0797; GA ČR(CZ) GAP305/11/2476 Institutional research plan: CEZ:AV0Z50380511 Keywords : Auxin homeostasis * DR5 * Auxin carrier Subject RIV: ED - Physiology Impact factor: 3.942, year: 2013

  10. Filtered Carrier Phase Estimator for High-Order QAM Optical Systems

    DEFF Research Database (Denmark)

    Rozental, Valery; Kong, Deming; Corcoran, Bill

    2018-01-01

    We investigate, using Monte Carlo simulations, the performance characteristics and limits of a low-complexity filtered carrier phase estimator (F-CPE) in terms of cycle slip occurrences and SNR penalties. In this work, the F-CPE algorithm has been extended to include modulation formats whose oute...

  11. Estimating changes in urban ozone concentrations due to life cycle emissions from hydrogen transportation systems

    Science.gov (United States)

    Wang, Guihua; Ogden, Joan M.; Chang, Daniel P. Y.

    Hydrogen has been proposed as a low polluting alternative transportation fuel that could help improve urban air quality. This paper examines the potential impact of introducing a hydrogen-based transportation system on urban ambient ozone concentrations. This paper considers two scenarios, where significant numbers of new hydrogen vehicles are added to a constant number of gasoline vehicles. In our scenarios hydrogen fuel cell vehicles (HFCVs) are introduced in Sacramento, California at market penetrations of 9% and 20%. From a life cycle analysis (LCA) perspective, considering all the emissions involved in producing, transporting, and using hydrogen, this research compares three hypothetical natural gas to hydrogen pathways: (1) on-site hydrogen production; (2) central hydrogen production with pipeline delivery; and (3) central hydrogen production with liquid hydrogen truck delivery. Using a regression model, this research shows that the daily maximum temperature correlates well with atmospheric ozone formation. However, increases in initial VOC and NO x concentrations do not necessarily increase the peak ozone concentration, and may even cause it to decrease. It is found that ozone formation is generally limited by NO x in the summer and is mostly limited by VOC in the fall in Sacramento. Of the three hydrogen pathways, the truck delivery pathway contributes the most to ozone precursor emissions. Ozone precursor emissions from the truck pathway at 9% market penetration can cause additional 3-h average VOC (or NO x) concentrations up to approximately 0.05% (or 1%) of current pollution levels, and at 20% market penetration up to approximately 0.1% (or 2%) of current pollution levels. However, all of the hydrogen pathways would result in very small (either negative or positive) changes in ozone air quality. In some cases they will result in worse ozone air quality (mostly in July, August, and September), and in some cases they will result in better ozone air quality

  12. Estimating changes in urban ozone concentrations due to life cycle emissions from hydrogen transportation systems

    International Nuclear Information System (INIS)

    Guihua Wang; Ogden, Joan M.; Chang, Daniel P.Y.

    2007-01-01

    Hydrogen has been proposed as a low polluting alternative transportation fuel that could help improve urban air quality. This paper examines the potential impact of introducing a hydrogen-based transportation system on urban ambient ozone concentrations. This paper considers two scenarios, where significant numbers of new hydrogen vehicles are added to a constant number of gasoline vehicles. In our scenarios hydrogen fuel cell vehicles (HFCVs) are introduced in Sacramento, California at market penetrations of 9% and 20%. From a life cycle analysis (LCA) perspective, considering all the emissions involved in producing, transporting, and using hydrogen, this research compares three hypothetical natural gas to hydrogen pathways: (1) on-site hydrogen production; (2) central hydrogen production with pipeline delivery; and (3) central hydrogen production with liquid hydrogen truck delivery. Using a regression model, this research shows that the daily maximum temperature correlates well with atmospheric ozone formation. However, increases in initial VOC and NO x concentrations do not necessarily increase the peak ozone concentration, and may even cause it to decrease. It is found that ozone formation is generally limited by NO x in the summer and is mostly limited by VOC in the fall in Sacramento. Of the three hydrogen pathways, the truck delivery pathway contributes the most to ozone precursor emissions. Ozone precursor emissions from the truck pathway at 9% market penetration can cause additional 3-h average VOC (or NO x ) concentrations up to approximately 0.05% (or 1%) of current pollution levels, and at 20% market penetration up to approximately 0.1% (or 2%) of current pollution levels. However, all of the hydrogen pathways would result in very small (either negative or positive) changes in ozone air quality. In some cases they will result in worse ozone air quality (mostly in July, August, and September), and in some cases they will result in better ozone air

  13. Hydrogen Fuel System Design Trades for High-Altitude Long-Endurance Remotely- Operated Aircraft

    Science.gov (United States)

    Millis, Marc G.; Tornabene, Robert T.; Jurns, John M.; Guynn, Mark D.; Tomsik, Thomas M.; VanOverbeke, Thomas J.

    2009-01-01

    Preliminary design trades are presented for liquid hydrogen fuel systems for remotely-operated, high-altitude aircraft that accommodate three different propulsion options: internal combustion engines, and electric motors powered by either polymer electrolyte membrane fuel cells or solid oxide fuel cells. Mission goal is sustained cruise at 60,000 ft altitude, with duration-aloft a key parameter. The subject aircraft specifies an engine power of 143 to 148 hp, gross liftoff weight of 9270 to 9450 lb, payload of 440 lb, and a hydrogen fuel capacity of 2650 to 2755 lb stored in two spherical tanks (8.5 ft inside diameter), each with a dry mass goal of 316 lb. Hydrogen schematics for all three propulsion options are provided. Each employs vacuum-jacketed tanks with multilayer insulation, augmented with a helium pressurant system, and using electric motor driven hydrogen pumps. The most significant schematic differences involve the heat exchangers and hydrogen reclamation equipment. Heat balances indicate that mission durations of 10 to 16 days appear achievable. The dry mass for the hydrogen system is estimated to be 1900 lb, including 645 lb for each tank. This tank mass is roughly twice that of the advanced tanks assumed in the initial conceptual vehicle. Control strategies are not addressed, nor are procedures for filling and draining the tanks.

  14. Hydrogen production system coupled with high-temperature gas-cooled reactor (HTTR)

    International Nuclear Information System (INIS)

    Shiozawa, Shusaku

    2003-01-01

    On the HTTR program, R and D on nuclear reactor technology and R and D on thermal application technology such as hydrogen production and so on, are advanced. When carrying out power generation and thermal application such as hydrogen production and so on, it is, at first, necessary to supply nuclear heat safely, stably and in low cost, JAERI carries out some R and Ds on nuclear reactor technology using HTTR. In parallel to this, JAERI also carries out R and D for jointing nuclear reactor system with thermal application systems because of no experience in the world on high temperature heat of about 1,000 centigrade supplied by nuclear reactor except power generation, and R and D on thermochemical decomposition method IS process for producing hydrogen from water without exhaust of carbon dioxide. Here were described summaries on R and D on nuclear reactor technology, R and D on jointing technology using HTTR hydrogen production system, R and D on IS process hydrogen production, and comparison hydrogen production with other processes. (G.K.)

  15. The role of hydrogen in high wind energy penetration electricity systems: the Irish case

    International Nuclear Information System (INIS)

    Gonzalez, A.; McKeogh, E.; Gallachoir, B.O.

    2004-01-01

    The deployment of wind energy is constrained by wind uncontrollability, which poses operational problems on the electricity supply system at high penetration levels, lessening the value of wind-generated electricity to a significant extent. This paper studies the viability of hydrogen production via electrolysis using wind power that cannot be easily accommodated on the system. The potential benefits of hydrogen and its role in enabling a large penetration of wind energy are assessed, within the context of the enormous wind energy resource in Ireland. The exploitation of this wind resource may in the future give rise to significant amounts of surplus wind electricity, which could be used to produce hydrogen, the zero-emissions fuel that many experts believe will eventually replace fossil fuels in the transport sector. In this paper the operation of a wind powered hydrogen production system is simulated and optimised. The results reveal that, even allowing for significant cost-reductions in electrolyser and associated balance-of-plant equipment, low average surplus wind electricity cost and a high hydrogen market price are also necessary to achieve the economic viability of the technology. These conditions would facilitate the installation of electrolysis units of sufficient capacity to allow an appreciable increase in installed wind power in Ireland. The simulation model was also used to determine the CO 2 abatement potential associated with the wind energy/hydrogen production. (author)

  16. Development of the Integrated Hydrogen Production System Using Micro-structured Devices

    International Nuclear Information System (INIS)

    Jung Min Sohn; Young Chang Byun; Jun Yeon Cho; Youngwoon Kwon; Jaehoon Choe

    2006-01-01

    A plate-type integrated fuel processor, which consisted of three different micro-reactors which were a reformer with combustor, two heat exchangers and an evaporator with combustor, was developed for the hydrogen production as feed of over 100 W-grade PEMFC. The methanol steam reforming was chosen in our fuel processor to produce highly pure hydrogen. Our system could be operated without any external electric heat supply. Hydrogen which might come from off gas was used as the combustion fuel at initial stage and methanol was used during the steam reaction. Cu/Zn/Al 2 O 3 and Pt/Al 2 O 3 catalysts were chosen for steam reforming of methanol and the combustion and coated on microchannel-patterned stainless steel sheets. The performance of the fuel processor was tested for long-term use. The integrated system was operated consistently with methanol conversion of over 80.0 mol% at 300 C for 20 hrs without deactivation of catalyst. The maximum composition of hydrogen and production rate on dry basis was about 70 % and 1.7 L/min, respectively. The efficiency of our system was calculated based on the LHV of methanol and hydrogen. Overall thermal efficiency of our fuel processor was 59.5 % and thermal power of hydrogen was about 300 W. (authors)

  17. A new boil-off gas re-liquefaction system for LNG carriers based on dual mixed refrigerant cycle

    Science.gov (United States)

    Tan, Hongbo; Shan, Siyu; Nie, Yang; Zhao, Qingxuan

    2018-06-01

    A new boil-off gas (BOG) re-liquefaction system for LNG carriers has been proposed to improve the system energy efficiency. Two cascade mixed refrigerant cycles (or dual mixed refrigerant cycle, DMR) are used to provide the cooling capacity for the re-liquefaction of BOG. The performance of the new system is analysed on the basis of the thermodynamic data obtained in the process simulation in Aspen HYSYS software. The results show that the power consumed in the BOG compressor and the high-temperature mixed refrigerant compressor could be saved greatly due to the reduced mass flow rates of the processed fluids. Assuming the re-liquefaction capacity of the investigated system is 4557.6 kg/h, it is found that the total power consumption can be reduced by 25%, from 3444 kW in the existing system to 2585.8 kW in the proposed system. The coefficient of performance (COP) of 0.25, exergy efficiency of 41.3% and the specific energy consumption (SEC) of 0.589 kWh/kg(LNG) could be achieved in the new system. It exhibits 33% of improvement in the COP and exergy efficiency in comparison with the corresponding values of the existing system. It indicates that employing the DMR based BOG re-liquefaction system could improve the system energy efficiency of LNG carriers substantially.

  18. Nuclear energy for sustainable Hydrogen production

    International Nuclear Information System (INIS)

    Gyoshev, G.

    2004-01-01

    There is general agreement that hydrogen as an universal energy carrier could play increasingly important role in energy future as part of a set of solutions to a variety of energy and environmental problems. Given its abundant nature, hydrogen has been an important raw material in the organic chemical industry. At recent years strong competition has emerged between nations as diverse as the U.S., Japan, Germany, China and Iceland in the race to commercialize hydrogen energy vehicles in the beginning of 21st Century. Any form of energy - fossil, renewable or nuclear - can be used to generate hydrogen. The hydrogen production by nuclear electricity is considered as a sustainable method. By our presentation we are trying to evaluate possibilities for sustainable hydrogen production by nuclear energy at near, medium and long term on EC strategic documents basis. The main EC documents enter water electrolysis by nuclear electricity as only sustainable technology for hydrogen production in early stage of hydrogen economy. In long term as sustainable method is considered the splitting of water by thermochemical technology using heat from high temperature reactors too. We consider that at medium stage of hydrogen economy it is possible to optimize the sustainable hydrogen production by high temperature and high pressure water electrolysis by using a nuclear-solar energy system. (author)

  19. Release of hydrogen sulfide in a sewer system under intermittent flow conditions

    DEFF Research Database (Denmark)

    Matias, Natércia; Matos, Rita Ventura; Ferreira, Filipa

    2017-01-01

    The presence and fate of hydrogen sulfide in wastewater systems were studied in two stretches of an intercepting sewer system located in a coastal village, in Portugal. A range of hydraulic parameters were obtained and liquid and gas phase measurements were carried out, both conti