The production of hydrogen-rich gas by wet sludge pyrolysis using waste heat from blast-furnace slag

International Nuclear Information System (INIS)

Luo, Siyi; Feng, Yu

2016-01-01

Blast furnace (BF) slag, a byproduct of steelmaking industry, contains a large amount of sensible heat and is composed of some metal oxides, which exhibits preferable catalytic performance in improving tar cracking and C_nH_m reforming. This paper presents a heat recovery system from the heat of BF slag, which generates hydrogen-rich gas via the endothermic reactions of sludge pyrolysis. The effects of various parameters including the slag temperature, the mass ratio of slag to sludge (B/S), particle size and feed moisture on product yields and gas characteristics were evaluated separately. It was found that the pyrolysis products distribution was significantly influenced by the BF slag temperature. The differences resulting from varying B/S practically disappear as higher temperature heat carrier is approached. The optimum feed moisture was in favour of sludge pyrolysis by getting char and tar participate in gasification reactions, improving gas yield and quality. BF slag as catalyst can greatly increase H_2 and CO contents of gas by improving tar degradation and reforming of biogas (CO_2 and CH_4). Decreasing the slag particles size was helpful to sludge primary pyrolysis to produce more light gases, less char and condensate, while its effects on gas compositions was not evident. - Highlights: • The sensible heat of molten slag was recovered and converted into combustible gas. • A novel rotary pyrolysis reactor using BF slag as heat carrier was presented. • The moisture in sludge was used as the gasification medium and hydrogen source.

The Stability of Hydrogen-Rich Atmospheres of Earth-Like Planets

Science.gov (United States)

Zahnle, Kevin

2016-01-01

Understanding hydrogen escape is essential to understanding the limits to habitability, both for liquid water where the Sun is bright, but also to assess the true potential of H2 as a greenhouse gas where the Sun is faint. Hydrogen-rich primary atmospheres of Earth-like planets can result either from gravitational capture of solar nebular gases (with helium), or from impact shock processing of a wide variety of volatile-rich planetesimals (typically accompanied by H2O, CO2, and under the right circumstances, CH4). Most studies of hydrogen escape from planets focus on determining how fast the hydrogen escapes. In general this requires solving hydro- dynamic equations that take into account the acceleration of hydrogen through a critical transonic point and an energy budget that should include radiative heating and cooling, thermal conduction, the work done in lifting the hydrogen against gravity, and the residual heat carried by the hydrogen as it leaves. But for planets from which hydrogen escape is modest or insignificant, the atmosphere can be approximated as hydrostatic, which is much simpler, and for which a relatively full-featured treatment of radiative cooling by embedded molecules, atoms, and ions such as CO2 and H3+ is straightforward. Previous work has overlooked the fact that the H2 molecule is extremely efficient at exciting non-LTE CO2 15 micron emission, and thus that radiative cooling can be markedly more efficient when H2 is abundant. We map out the region of phase space in which terrestrial planets keep hydrogen-rich atmospheres, which is what we actually want to know for habitability. We will use this framework to reassess Tian et al's hypothesis that H2-rich atmospheres may have been rather long-lived on Earth itself. Finally, we will address the empirical observation that rocky planets with thin or negligible atmospheres are rarely or never bigger than 1.6 Earth radii.

Production of hydrogen by thermocatalytic cracking of natural gas

Energy Technology Data Exchange (ETDEWEB)

Muradov, N. [Florida Solar Energy Center, Cocoa, FL (United States)

1996-10-01

The conventional methods of hydrogen production from natural gas (for example, steam reforming and partial oxidation) are complex, multi-step processes that produce large quantities of CO{sub 2}. The main goal of this project is to develop a technologically simple process for hydrogen production from natural gas (NG) and other hydrocarbon fuels via single-step decomposition of hydrocarbons. This approach eliminates or significantly reduces CO{sub 2} emission. Carbon is a valuable by-product of this process, whereas conventional methods of hydrogen production from NG produce no useful by-products. This approach is based on the use of special catalysts that reduce the maximum temperature of the process from 1400-1500{degrees}C (thermal non-catalytic decomposition of methane) to 500-900{degrees}C. Transition metal based catalysts and various forms of carbon are among the candidate catalysts for the process. This approach can advantageously be used for the development of compact NG reformers for on-site production of hydrogen-methane blends at refueling stations and, also, for the production of hydrogen-rich gas for fuel cell applications. The author extended the search for active methane decomposition catalysts to various modifications of Ni-, Fe-, Mo- and Co-based catalysts. Variation in the operational parameters makes it possible to produce H{sub 2}-CH{sub 4} blends with a wide range of hydrogen concentrations that vary from 15 to 98% by volume. The author found that Ni-based catalysts are more effective at temperatures below 750{degrees}C, whereas Fe-based catalysts are effective at temperatures above 800{degrees}C for the production of hydrogen with purity of 95% v. or higher. The catalytic pyrolysis of liquid hydrocarbons (pentane, gasoline) over Fe-based catalyst was conducted. The author observed the production of a hydrogen-rich gas (hydrogen concentration up to 97% by volume) at a rate of approximately 1L/min.mL of hydrocarbon fuel.

Hydrogen gas detector

International Nuclear Information System (INIS)

Bohl, T.L.

1982-01-01

A differential thermocouple hydrogen gas detector has one thermocouple junction coated with an activated palladium or palladium-silver alloy catalytic material to allow heated hydrogen gas to react with the catalyst and raise the temperature of that junction. The other juction is covered with inert glass or epoxy resin, and does not experience a rise in temperature in the presence of hydrogen gas. A coil heater may be mounted around the thermocouple junctions to heat the hydrogen, or the gas may be passed through a heated block prior to exposing it to the thermocouples

LHCB RICH gas system proposal

CERN Document Server

Bosteels, Michel; Haider, S

2001-01-01

Both LHCb RICH will be operated with fluorocarbon as gas radiator. RICH 1 will be filled with 4m^3 of C4F10 and RICH 2 with 100m^3 of CF4. The gas systems will run as a closed loop circulation and a gas recovery system within the closed loop is planned for RICH 1, where the recovery of the CF4 will only be realised during filling and emptying of the detector. Inline gas purification is foreseen for the gas systems in order to limit water and oxygen impurities.

Performance Improvement of V-Fe-Cr-Ti Solid State Hydrogen Storage Materials in Impure Hydrogen Gas.

Science.gov (United States)

Ulmer, Ulrich; Oertel, Daria; Diemant, Thomas; Bonatto Minella, Christian; Bergfeldt, Thomas; Dittmeyer, Roland; Behm, R Jürgen; Fichtner, Maximilian

2018-01-17

Two approaches of engineering surface structures of V-Ti-based solid solution hydrogen storage alloys are presented, which enable improved tolerance toward gaseous oxygen (O 2 ) impurities in hydrogen (H 2 ) gas. Surface modification is achieved through engineering lanthanum (La)- or nickel (Ni)-rich surface layers with enhanced cyclic stability in an H 2 /O 2 mixture. The formation of a Ni-rich surface layer does not improve the cycling stability in H 2 /O 2 mixtures. Mischmetal (Mm, a mixture of La and Ce) agglomerates are observed within the bulk and surface of the alloy when small amounts of this material are added during arc melting synthesis. These agglomerates provide hydrogen-transparent diffusion pathways into the bulk of the V-Ti-Cr-Fe hydrogen storage alloy when the remaining oxidized surface is already nontransparent for hydrogen. Thus, the cycling stability of the alloy is improved in an O 2 -containing hydrogen environment as compared to the same alloy without addition of Mm. The obtained surface-engineered storage material still absorbs hydrogen after 20 cycles in a hydrogen-oxygen mixture, while the original material is already deactivated after 4 cycles.

Hydrogen separation process

Science.gov (United States)

Mundschau, Michael [Longmont, CO; Xie, Xiaobing [Foster City, CA; Evenson, IV, Carl; Grimmer, Paul [Longmont, CO; Wright, Harold [Longmont, CO

2011-05-24

A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to a hydrogen separation membrane system comprising a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for separating a hydrogen-rich product stream from a feed stream comprising hydrogen and at least one carbon-containing gas, comprising feeding the feed stream, at an inlet pressure greater than atmospheric pressure and a temperature greater than 200.degree. C., to an integrated water gas shift/hydrogen separation membrane system wherein the hydrogen separation membrane system comprises a membrane that is selectively permeable to hydrogen, and producing a hydrogen-rich permeate product stream on the permeate side of the membrane and a carbon dioxide-rich product raffinate stream on the raffinate side of the membrane. A method for pretreating a membrane, comprising: heating the membrane to a desired operating temperature and desired feed pressure in a flow of inert gas for a sufficient time to cause the membrane to mechanically deform; decreasing the feed pressure to approximately ambient pressure; and optionally, flowing an oxidizing agent across the membrane before, during, or after deformation of the membrane. A method of supporting a hydrogen separation membrane system comprising selecting a hydrogen separation membrane system comprising one or more catalyst outer layers deposited on a hydrogen transport membrane layer and sealing the hydrogen separation membrane system to a porous support.

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.

Hydrogen rich gas production by thermocatalytic decomposition of kenaf biomass

Energy Technology Data Exchange (ETDEWEB)

Irmak, Sibel; Oeztuerk, ilker [Department of Chemistry, Cukurova University, Arts and Sciences Faculty, Adana 01330 (Turkey)

2010-06-15

Kenaf (Hibiscus cannabinus L.), a well known energy crop and an annual herbaceous plant grows very fast with low lodging susceptibility was used as representative lignocellulosic biomass in the present work. Thermocatalytic conversions were performed by aqueous phase reforming (APR) of kenaf hydrolysates and direct gasification of solid biomass of kenaf using 5% Pt on activated carbon as catalyst. Hydrolysates used in APR experiments were prepared by solubilization of kenaf biomass in subcritical water under CO{sub 2} gas pressure. APR of kenaf hydrolysate with low molecular weight polysaccharides in the presence of the reforming catalyst produced more gas compared to the hydrolysate that had high molecular weight polysaccharides. APR experiments of kenaf biomass hydrolysates and glucose, which was used as a simplest biomass model compound, in the presence of catalyst produced various amounts of gas mixtures that consisted of H{sub 2}, CO, CO{sub 2}, CH{sub 4} and C{sub 2}H{sub 6}. The ratios of H{sub 2} to other gases produced were 0.98, 1.50 and 1.35 for 150 C and 250 C subcritical water-treated kenaf hydrolysates and glucose, respectively. These ratios indicated that more the degraded organic content of kenaf hydrolysate the better selectivity for hydrogen production. Although APR of 250 C-kenaf hydrolysate resulted in similar gas content and composition as glucose, the gas volume produced was three times higher in glucose feed. The use of solid kenaf biomass as starting feedstock in APR experiments resulted in less gas production since the activity of catalyst was lowered by solid biomass particles. (author)

Measurement of dissolved hydrogen and hydrogen gas transfer in a hydrogen-producing reactor

Energy Technology Data Exchange (ETDEWEB)

Shizas, I.; Bagley, D.M. [Toronto Univ., ON (Canada). Dept. of Civil Engineering

2004-07-01

This paper presents a simple method to measure dissolved hydrogen concentrations in the laboratory using standard equipment and a series of hydrogen gas transfer tests. The method was validated by measuring hydrogen gas transfer parameters for an anaerobic reactor system that was purged with 10 per cent carbon dioxide and 90 per cent nitrogen using a coarse bubble diffuser stone. Liquid samples from the reactor were injected into vials and hydrogen was allowed to partition between the liquid and gaseous phases. The concentration of dissolved hydrogen was determined by comparing the headspace injections onto a gas chromatograph and a standard curve. The detection limit was 1.0 x 10{sup -5} mol/L of dissolved hydrogen. The gas transfer rate for hydrogen in basal medium and anaerobic digester sludge was used to validate the method. Results were compared with gas transfer models. In addition to monitoring dissolved hydrogen in reactor systems, this method can help improve hydrogen production potential. 1 ref., 4 figs.

Hydrogen-rich gas production from waste plastics by pyrolysis and low-temperature steam reforming over a ruthenium catalyst

International Nuclear Information System (INIS)

Namioka, Tomoaki; Saito, Atsushi; Inoue, Yukiharu; Park, Yeongsu; Min, Tai-jin; Roh, Seon-ah; Yoshikawa, Kunio

2011-01-01

Operating conditions for low-temperature pyrolysis and steam reforming of plastics over a ruthenium catalyst were investigated. In the range studied, the highest gas and lowest coke fractions for polystyrene (PS) with a 60 g h -1 scale, continuous-feed, two-stage gasifier were obtained with a pyrolyzer temperature of 673 K, steam reforming temperature of 903 K, and weight hourly space velocity (WHSV) of 0.10 g-sample g-catalyst -1 h -1 . These operating conditions are consistent with optimum conditions reported previously for polypropylene. Our results indicate that at around 903 K, the activity of the ruthenium catalyst was high enough to minimize the difference between the rates of the steam reforming reactions of the pyrolysates from polystyrene and polypropylene. The proposed system thus has the flexibility to compensate for differences in chemical structures of municipal waste plastics. In addition, the steam reforming temperature was about 200 K lower than the temperature used in a conventional Ni-catalyzed process for the production of hydrogen. Low-temperature steam reforming allows for lower thermal input to the steam reformer, which results in an increase in thermal efficiency in the proposed process employing a Ru catalyst. Because low-temperature steam reforming can be also expected to reduce thermal degradation rates of the catalyst, the pyrolysis-steam reforming process with a Ru catalyst has the potential for use in small-scale production of hydrogen-rich gas from waste plastics that can be used for power generation.

Performance and emissions of a supercharged dual-fuel engine fueled by hydrogen-rich coke oven gas

Energy Technology Data Exchange (ETDEWEB)

Roy, M.M.; Tomita, E.; Kawahara, N.; Harada, Y.; Sakane, A. [Okayama University, Okayama (Japan). Dept. of Mechanical Engineering

2009-12-15

This study investigated the engine performance and emissions of a supercharged dual-fuel engine fueled by hydrogen-rich coke oven gas and ignited by a pilot amount of diesel fuel. The engine was tested for use as a cogeneration engine, so power output while maintaining a reasonable thermal efficiency was important. Experiments were carried out at a constant pilot injection pressure and pilot quantity for different fuel-air equivalence ratios and at various injection timings without and with exhaust gas recirculation (EGR). The experimental strategy was to optimize the injection timing to maximize engine power at different fuel-air equivalence ratios without knocking and within the limit of the maximum cylinder pressure. The engine was tested first without EGR condition up to the maximum possible fuel-air equivalence ratio of 0.65. A maximum indicated mean effective pressure (IMEP) of 1425 kPa and a thermal efficiency of 39% were obtained. However, the nitrogen oxides (NOx) emissions were high. A simulated EGR up to 50% was then performed to obtain lower NOx emissions. The maximum reduction of NOx was 60% or more maintaining the similar levels of IMEP and thermal efficiency. Two-stage combustion was obtained; this is an indicator of maximum power output conditions and a precursor of knocking combustion.

Development of a Low NOx Medium sized Industrial Gas Turbine Operating on Hydrogen-Rich Renewable and Opportunity Fuels

Energy Technology Data Exchange (ETDEWEB)

Srinivasan, Ram

2013-07-31

This report presents the accomplishments at the completion of the DOE sponsored project (Contract # DE-FC26-09NT05873) undertaken by Solar Turbines Incorporated. The objective of this 54-month project was to develop a low NOx combustion system for a medium sized industrial gas turbine engine operating on Hydrogen-rich renewable and opportunity Fuels. The work in this project was focused on development of a combustion system sized for 15MW Titan 130 gas turbine engine based on design analysis and rig test results. Although detailed engine evaluation of the complete system is required prior to commercial application, those tasks were beyond the scope of this DOE sponsored project. The project tasks were organized in three stages, Stages 2 through 4. In Stage 2 of this project, Solar Turbines Incorporated characterized the low emission capability of current Titan 130 SoLoNOx fuel injector while operating on a matrix of fuel blends with varying Hydrogen concentration. The mapping in this phase was performed on a fuel injector designed for natural gas operation. Favorable test results were obtained in this phase on emissions and operability. However, the resulting fuel supply pressure needed to operate the engine with the lower Wobbe Index opportunity fuels would require additional gas compression, resulting in parasitic load and reduced thermal efficiency. In Stage 3, Solar characterized the pressure loss in the fuel injector and developed modifications to the fuel injection system through detailed network analysis. In this modification, only the fuel delivery flowpath was modified and the air-side of the injector and the premixing passages were not altered. The modified injector was fabricated and tested and verified to produce similar operability and emissions as the Stage 2 results. In parallel, Solar also fabricated a dual fuel capable injector with the same air-side flowpath to improve commercialization potential. This injector was also test verified to produce 15

Co-pyrolysis of waste tire/coal mixtures for smokeless fuel, maltenes and hydrogen-rich gas production

International Nuclear Information System (INIS)

Bičáková, Olga; Straka, Pavel

2016-01-01

Highlights: • Co-pyrolysis of waste tires/coal mixtures yields mainly smokeless fuel (55–74 wt%). • Alternatively, the smokeless fuel can serve as carbonaceous sorbent. • The obtained tar contained maltenes (80–85 wt%) and asphaltenes (6–8 wt%). • Tar from co-pyrolysis can serve as heating oil or a source of maltenes for repairing of asphalt surfaces. • The hydrogen-rich gas was obtained (61–65 vol% H_2, 24–25 vol% CH_4, 1.4–2 vol% CO_2). - Abstract: The processing of waste tires with two different types of bituminous coal was studied through the slow co-pyrolysis of 1 kg of waste tire/coal mixtures with 15, 30 and 60 wt% waste tires on a laboratory scale. The waste tire/coal mixtures were pyrolysed using a quartz reactor in a stationary bed. The mixtures were heated at a rate 5 °C/min up to the final temperature of 900 °C with a soaking time of 30 min at the required temperature. The mass balance of the process and the properties of the coke and tar obtained were evaluated, further, the influence of the admixture in the charge on the amount and composition of the obtained coke and tar was determined. It was found that the smokeless fuel/carbonaceous sorbent and a high yield of tar for further use can be obtained through the slow co-pyrolysis. The obtained tars contained mostly maltenes (80–85 wt%). FTIR analysis showed that the maltenes from the co-pyrolysis of coal/waste tires exhibited significantly lower aromaticity as compared with that from coal alone. The gas obtained from pyrolysis or co-pyrolysis of waste tire/coal mixtures contained a high amount of hydrogen (above 60 vol%) and methane (above 20 vol%).

Generation of oxy-hydrogen gas and its effect on performance of spark ignition engine

Science.gov (United States)

Patil, N. N.; Chavan, C. B.; More, A. S.; Baskar, P.

2017-11-01

Considering the current scenario of petroleum fuels, it has been observed that, they will last for few years from now. On the other hand, the ever increasing cost of a gasoline fuels and their related adverse effects on environment caught the attention of researchers to find a supplementary source. For commercial fuels, supplementary source is not about replacing the entire fuel, instead enhancing efficiency by simply making use of it in lesser amount. From the recent research that has been carried out, focus on the use of Hydrogen rich gas as a supplementary source of fuel has increased. But the problem related to the storage of hydrogen gas confines the application of pure hydrogen in petrol engine. Using oxy-hydrogen gas (HHO) generator the difficulties of storing the hydrogen have overcome up to a certain limit. The present study highlights on performance evaluation of conventional petrol engine by using HHO gas as a supplementary fuel. HHO gas was generated from the electrolysis of water. KOH solution of 3 Molar concentration was used which act as a catalyst and accelerates the rate of generation of HHO gas. Quantity of gas to be supplied to the engine was controlled by varying amount of current. It was observed that, engine performance was improved on the introduction of HHO gas.

Hydrogen gas sample environment for TOSCA

International Nuclear Information System (INIS)

Kibble, Mark G; Ramirez-Cuesta, Anibal J; Goodway, Chris M; Evans, Beth E; Kirichek, Oleg

2014-01-01

The idea of using hydrogen as a fuel has gained immense popularity over many years. Hydrogen is abundant, can be produced from renewable resources and is not a greenhouse gas. However development of hydrogen based technology is impossible without understanding of physical and chemical processes that involve hydrogen sometime in extreme conditions such as high pressure or low and high temperatures. Neutron spectroscopy allows measurement of a hydrogen atom motion in variety of samples. Here we describe and discuss a sample environment kit developed for hydrogen gas experiment in a broad range of pressure up to 7 kbar and temperatures from 4 K to 473 K. We also describe para-hydrogen rig which produces para-hydrogen gas required for studying the rotational line of molecular hydrogen

A Review on Preferential Oxidation of Carbon Monoxide in Hydrogen Rich Gases

Directory of Open Access Journals (Sweden)

A. Mishra

2011-05-01

Full Text Available In this review, recent works on the preferential oxidation of carbon monoxide in hydrogen rich gases for fuel cell applications are summarized. H2 is used as a fuel for polymer-electrolyte membrane fuel cell (PEMFC. It is produced by reforming of natural gas or liquid fuels followed by water gas shift reaction. The produced gas consists of H2, CO, and CO2. In which CO content is around 1%, which is highly poisonous for the Pt anode of the PEMFC so that further removal of CO is needed. Catalytic preferential oxidation of CO (CO-PROX is one of the most suitable methods of purification of H2 because of high CO conversion rate at low temperature range, which is preferable for PEMFC operating conditions. Catalysts used for COPROX are mainly noble metal based; gold based and base metal oxide catalysts among them Copper-Ceria based catalysts are the most appropriate due to its low cost, easy availability and result obtained by these catalysts are comparable with the conventional noble metal catalysts. Copyright © 2011 BCREC UNDIP. All rights reserved(Received: 22nd October 2010, Revised: 12nd January 2011, Accepted: 19th January 2011[How to Cite: A. Mishra, R. Prasad. (2011. A Review on Preferential Oxidation of Carbon Monoxide in Hydrogen Rich Gases. Bulletin of Chemical Reaction Engineering & Catalysis, 6 (1: 1-14. doi:10.9767/bcrec.6.1.191.1-14][How to Link / DOI: http://dx.doi.org/10.9767/bcrec.6.1.191.1-14 || or local:  http://ejournal.undip.ac.id/index.php/bcrec/article/view/191] | View in 

Proposal for a Northeast Asian Hydrogen Highway: From a Natural-gas-based to a Hydrogen-based Society

International Nuclear Information System (INIS)

Kazuhiko O Hashi; Masaru Hirata; William C Leighty; D Eng

2006-01-01

In Northeast Asia, East Siberia and Sakhalin are rich in natural gas (NG). The environmental protection and energy security of the Northeast Asian region requires constructing an energy infrastructure network that can transport and distribute NG throughout the region in the near term, and renewable-source gaseous hydrogen (GH2) in the long term. We have promoted the construction of an NG pipeline network, the principal component of the energy infrastructure essential to our evolution toward a hydrogen-based society, through the Northeast Asia Natural Gas and Pipeline Forum (NAGPF). Our ultimate goal is a clean and sustainable society based on renewable energy sources, wherein hydrogen is produced from the vast potential of renewable energy in Siberia and China. The hydrogen thus produced would be transmitted through the pipeline network, progressively replacing NG as it is depleted. Over three-quarters of commercially exploitable hydroelectric power (hydro) resources of all Russia is in East Siberia. The areas from Kamchatka through the Kurilskiye Islands (called the Chishima Islands, in Japan) to Sakhalin is a world-class wind energy resource. West China has huge potential for solar energy. (authors)

Sewage sludge based producer gas of rich H{sub 2} content as a fuel for an IC engine

Energy Technology Data Exchange (ETDEWEB)

Szwaja, Stanislaw; Cupial, Karol [Czestochowa Univ. of Technology (Poland)

2010-07-01

The manuscript presents investigation on hydrogen rich gas combustion in an internal combustion (IC) engine. The gas is obtained from gasification process of sewage sludge which is by-product of waste water treatment in a municipal sewage treatment plant. Recently introduced EU regulations of environmental protection do not allow to use such sludge as a soil fertilizer or substance for landfilling the ground due to its biological toxicity. On another hand, this sludge contains organic content of approximately 45-55% and from this point of view the sludge looks as an attractive material for fuel production through its gasification. This technology, primarily applied for wood gasification, has been also successfully implemented for gasification of sludge. It was found that the producer gas obtained in this way is rich of hydrogen content even up to 25%. This is because of high water content in the sludge that provides favorable conditions for steam reforming resulting in increase of hydrogen in the products of gasification. The high hydrogen content in the producer gas can lead to improper combustion particularly when the combustion takes place in the internal combustion engine. That improper combustion might appear as combustion knock and it is the main problem for the engine in which hydrogen is used as a fuel [1]. Onset of the knock during combustion contributes to rapid increase in heat transfer to the piston crown causing the piston to be quickly overheated that leads to surface erosion and damages. Additionally, engine body vibration coming from the knock significantly shortens engine durability. Conclusions from this investigation provide good premises for combusting the sludge producer gas in the IC engine without any improper combustion anomalies, thus considers this gas as worthy fuel for a stationary engine driven a power generator. The presentation shows results of producer gas combustion in both the spark-ignited and the compression ignition engine with

Hydrogen-rich saline may be an effective and specific novel treatment for osteoradionecrosis of the jaw

Directory of Open Access Journals (Sweden)

Chen Y

2015-10-01

Full Text Available Yuanli Chen, Chunlin Zong, Yuxuan Guo, Lei Tian Department of Cranio-facial Trauma and Orthognathic Surgery Laboratory of Military Stomatology, School of Stomatology, The Fourth Military Medical University, Shaanxi Key Laboratory of Stomatology, Xi’an, People’s Republic of China Abstract: Hydrogen, a therapeutic medical gas, can exert antioxidant activity via selectively reducing cytotoxic reactive oxygen species such as hydroxyl radicals. Hydrogen-rich saline is an alternative form of molecular hydrogen that has been widely used in many studies, including metabolic syndrome, cerebral, hepatic, myocardial ischemia/reperfusion, and liver injuries with obstructive jaundice, with beneficial results. Osteoradionecrosis of the jaw is a serious complication following radiotherapy for head and neck cancers. It has long been known that most radiation-induced symptoms are caused by free radicals generated by radiolysis of H2O, and the hydroxyl radical is the most reactive of these. Reducing the hydroxyl radical can distinctly improve the protection of cells from radiation damage. We hypothesized that hydrogen-rich saline might be an effective and specific method of managing and preventing osteoradionecrosis of the jaw. Keywords: osteoradionecrosis, hydrogen, reactive oxygen species

Fuzzy logic control for selective hydrogenation of acetylene in ethylene rich streams using visual basic

International Nuclear Information System (INIS)

Malik, S.R.; Suleman, H.; Khan, J.R.

2010-01-01

Presence of acetylene is technically disadvantageous in the ethylene rich gas streams from steam crackers. Acetylene tends to polymerize and inactivates the transition metal catalysts, forming highly explosive compounds. The acetylene content has to be selectively reduced to less than one part per million for such streams. The acetylene hydrogenation unit requires stringent control parameters and needs specialized process control techniques for its operation. This study is concerned with application of Fuzzy Logic Control to manipulate and control the process plant with higher precision and greater simplicity. The control program has been written in visual Basic and entails all major scenarios of work modes for successful hydrogenation of Acetylene. (author)

Impact of hydrogen insertion on vehicular natural gas

Energy Technology Data Exchange (ETDEWEB)

Strangueto, Karina Maretti; Silva, Ennio Peres da [Universidade Estadual de Campinas (UNICAMP), SP (Brazil). Fac. of Mechanical Engineering. Energy Dept.], Email: karinakms@fem.unicamp.br

2010-07-01

This article aims to analyze the possibility of insertion of hydrogen in the vehicular natural gas or even the insertion of the hydrogen in the compressed natural gas used in Brazil. For the production of this hydrogen, the spilled turbinable energy from Itaipu would be harnessed. The calculation of production can be extended to other power plants which are close to the natural gas pipelines, where the hydrogen would be introduced. Then, it was analyzed the consumption of natural gas in vehicles in Brazil, the regulation of transportation, the sales of compressed natural gas to fuelling station, the specifications that the piped gas should follow to be sold, and how much hydrogen could be accepted in the mix. (author)

WATER-GAS SHIFT WITH INTEGRATED HYDROGEN SEPARATION; A

International Nuclear Information System (INIS)

Maria Flytzani-Stephanopoulos; Jerry Meldon; Xiaomei Qi

2001-01-01

Optimization of the water-gas shift (WGS) reaction system for hydrogen production for fuel cells is of particular interest to the energy industry. To this end, it is desirable to couple the WGS reaction to hydrogen separation using a semi-permeable membrane, with both processes carried out at high temperature to improve reaction kinetics. Reduced equilibrium conversion of the WGS reaction at high temperatures is overcome by product H(sub 2) removal via the membrane. This project involves fundamental research and development of novel cerium oxide-based catalysts for the water-gas-shift reaction and the integration of these catalysts with Pd-alloy H(sub 2)-separation membranes supplying high purity hydrogen for fuel cell use. Conditions matching the requirements of coal gasifier-exit gas streams will be examined in the project. In the first year of the project, we prepared a series of nanostructured Cu- and Fe-containing ceria catalysts by a special gelation/precipitation technique followed by air calcination at 650 C. Each sample was characterized by ICP for elemental composition analysis, BET-N2 desorption for surface area measurement, and by temperature-programmed reduction in H(sub 2) to evaluate catalyst reducibility. Screening WGS tests with catalyst powders were conducted in a flow microreactor at temperatures in the range of 200-550 C. On the basis of both activity and stability of catalysts in simulated coal gas, and in CO(sub 2)-rich gases, a Cu-CeO(sub 2) catalyst formulation was selected for further study in this project. Details from the catalyst development and testing work are given in this report. Also in this report, we present H(sub 2) permeation data collected with unsupported flat membranes of pure Pd and Pd-alloys over a wide temperature window

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

OpenAIRE

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

2012-01-01

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

Attenuation of cigarette smoke-induced airway mucus production by hydrogen-rich saline in rats.

Directory of Open Access Journals (Sweden)

Yunye Ning

Full Text Available BACKGROUND: Over-production of mucus is an important pathophysiological feature in chronic airway disease such as chronic obstructive pulmonary disease (COPD and asthma. Cigarette smoking (CS is the leading cause of COPD. Oxidative stress plays a key role in CS-induced airway abnormal mucus production. Hydrogen protected cells and tissues against oxidative damage by scavenging hydroxyl radicals. In the present study we investigated the effect of hydrogen on CS-induced mucus production in rats. METHODS: Male Sprague-Dawley rats were divided into four groups: sham control, CS group, hydrogen-rich saline pretreatment group and hydrogen-rich saline control group. Lung morphology and tissue biochemical changes were determined by immunohistochemistry, Alcian Blue/periodic acid-Schiff staining, TUNEL, western blot and realtime RT-PCR. RESULTS: Hydrogen-rich saline pretreatment attenuated CS-induced mucus accumulation in the bronchiolar lumen, goblet cell hyperplasia, muc5ac over-expression and abnormal cell apoptosis in the airway epithelium as well as malondialdehyde increase in the BALF. The phosphorylation of EGFR at Tyr1068 and Nrf2 up-regulation expression in the rat lungs challenged by CS exposure were also abrogated by hydrogen-rich saline. CONCLUSION: Hydrogen-rich saline pretreatment ameliorated CS-induced airway mucus production and airway epithelium damage in rats. The protective role of hydrogen on CS-exposed rat lungs was achieved at least partly by its free radical scavenging ability. This is the first report to demonstrate that intraperitoneal administration of hydrogen-rich saline protected rat airways against CS damage and it could be promising in treating abnormal airway mucus production in COPD.

Gas-chromatographic separation of hydrogen isotopic mixtures

International Nuclear Information System (INIS)

Preda, Anisoara; Bidica, Nicolae

2005-01-01

Full text: Gas chromatographic separation of hydrogen isotopes have been reported in the literature since late of 1950's. Gas chromatography is primarily an analytical method, but because of its properties it may be used in many other fields with excellent results. A simple method is proposed for the gas-chromatographic analysis of complex gas mixtures containing hydrogen isotopes; the method is based on the substantial difference in the thermal conductivity of these isotopes. One of the main disadvantages of the conventional gas chromatography is the long retention times required for the analysis of hydrogen gas mixtures while the column is operated at very low temperature. The method described in this paper was based on using a capillary molecular sieve 5A column operated for this kind of separation at 173 K. The carrier gas was Ne and the detector was TCD. In the paper chromatograms for various carrier flow rates and various hydrogen isotope mixtures are presented. (authors)

Effects of Hydrogen-Rich Saline on Hepatectomy-Induced Postoperative Cognitive Dysfunction in Old Mice.

Science.gov (United States)

Tian, Yue; Guo, Shanbin; Zhang, Yan; Xu, Ying; Zhao, Ping; Zhao, Xiaochun

2017-05-01

This study aims to investigate the protective effects and underlying mechanisms of hydrogen-rich saline on the cognitive functions of elder mice with partial hepatectomy-induced postoperative cognitive dysfunction (POCD). Ninety-six old male Kunming mice were randomly divided into 4 groups (n = 24 each): control group (group C), hydrogen-rich saline group (group H), POCD group (group P), and POCD + hydrogen-rich saline group (group PH). Cognitive function was subsequently assessed using Morris water-maze (MWM) test. TNF-α and IL-1β levels were measured by enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry, along with NF-κB activity determined by ELISA. The morphology of hippocampal tissues were further observed by HE staining. Learning and memory abilities of mice were significantly impaired at day 10 and day 14 post-surgery, as partial hepatectomy significantly prolonged the escape latency, decreased time at the original platform quadrant and frequency of crossing in group P when compared to group C (p hydrogen-rich saline (group PH) partially rescued spatial memory and learning as it shortened escape latency and increased time and crossing frequency of original platform compared to group P (p hydrogen-rich saline. Hydrogen-rich saline can alleviate POCD via inhibiting NF-κB activity in the hippocampus and reducing inflammatory response.

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

Application of gas chromatography in hydrogen isotope separation

International Nuclear Information System (INIS)

Ye Xiaoqiu; Sang Ge; Peng Lixia; Xue Yan; Cao Wei

2008-01-01

The principle of gas chromatographic separation of hydrogen isotopes was briefly introduced. The main technology and their development of separating hydrogen isotopes, including elution chromatography, hydrogen-displacement chromatography, self-displacement chromatography and frontal chromatography were discussed in detail. The prospect of hydrogen isotope separation by gas chromatography was presented. (authors)

Catalytic steam gasification of biomass in fluidized bed at low temperature: Conversion from livestock manure compost to hydrogen-rich syngas

International Nuclear Information System (INIS)

Xiao, Xianbin; Le, Duc Dung; Li, Liuyun; Meng, Xianliang; Cao, Jingpei; Morishita, Kayoko; Takarada, Takayuki

2010-01-01

Utilizing large amounts of animal waste as a source of renewable energy has the potential to reduce its disposal problems and associated pollution issues. Gasification characteristics of the manure compost make it possible for low temperature gasification. In this paper, an energy efficient approach to hydrogen-rich syngas from manure compost is represented at relatively low temperature, around 600 o C, in a continuous-feeding fluidized bed reactor. The effects of catalyst performance, reactor temperature, steam, and reaction type on gas yield, gas composition, and carbon conversion efficiency are discussed. The Ni-Al 2 O 3 catalyst simultaneously promotes tar cracking and steam reforming. Higher temperature contributes to higher gas yield and carbon conversion. The steam introduction increases hydrogen yield, by steam reforming and water-gas shift reaction. Two-stage gasification is also tried, showing the advantage of better catalyst utilization and enhancing the catalytic reactions to some extent.

Internal dosimetry of tritiated hydrogen gas

International Nuclear Information System (INIS)

Peterman, B.F.; Johnson, J.R.; Dunford, D.W.; McElroy, R.G.C.

1985-02-01

This document is a report on experiments to quantify the doses that may occur from the tritium gas that is converted 'in vivo' to tritiated water following the exposure to tritiated hydrogen gas contaminated air. This report also includes theoretical evaluation of the radiological hazards from the uptake through skin of tritium from tritiated hydrogen adsorbed on surfaces

Feasibility study of hydrogen determination in blended gas mixture by an indigenously developed hydrogen determinator

International Nuclear Information System (INIS)

Gaikwad, Revati; Sonar, V.R.; Pandey, R.K.; Karekar, C.D.; Raul, Seema; Mahanty, B.; Kelkar, A.; Bhatt, R.B.; Behere, P.G.

2017-01-01

It is required to determine accurately the percentage composition of hydrogen in the blended gas of N 2 and H 2 prior to deliver to the sintering furnace. A feasibility study has been carried out to determine the percentage composition of hydrogen in the blended gas by using an indigenously developed hydrogen determinator. The instrument uses gas chromatograph-thermal conductivity (GC-TCD) technique to determine hydrogen. The flow of carrier gas was kept at 100 mL min -1 during the analysis. A very close agreement between the determined value and the reported value of hydrogen content in the commercially available N 2 -H 2 mixed cylinder was found by using the indigenous hydrogen determinator. (author)

Study of cycle-by-cycle variations of a spark ignition engine fueled with natural gas-hydrogen blends

Energy Technology Data Exchange (ETDEWEB)

Wang, Jinhua; Chen, Hao; Liu, Bing; Huang, Zuohua [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi' an Jiaotong University, Xi' an 710049 (China)

2008-09-15

Cycle-by-cycle variations of a spark ignition engine fueled with natural gas-hydrogen blends with hydrogen volumetric fraction of 0%, 12%, 23%, 30% and 40% were studied. The effect of hydrogen addition on cycle-by-cycle variations of the natural gas engine was analyzed. The results showed that the peak cylinder pressure, the maximum rate of pressure rise and the indicated mean effective pressure increased and their corresponding cycle-by-cycle variations decreased with the increase of hydrogen fraction at lean mixture operation. The interdependency between the combustion parameters and the corresponding crank angle tended to be strongly correlated with the increase of hydrogen fraction under lean mixture operation. Coefficient of variation of the indicated mean effective pressure gave a low level and is slightly influenced by hydrogen addition under the stoichiometric and relatively rich mixture operation while it decreased remarkably with the increase of hydrogen fraction under the lean mixture operation. The excessive air ratio at CoV{sub imep} = 10% extended to the leaner mixture side with the increase of hydrogen fraction and this indicated that the engine lean operating limit could be extended with hydrogen addition. (author)

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.

Desulfurization and denitrogenation in copyrolysis of coal with hydrogen-rich gases

Energy Technology Data Exchange (ETDEWEB)

Liao, H.; Li, B.; Zhang, B. [Chinese Academy of Sciences, Taiyuan (China). Institute of Coal Chemistry

1999-06-01

Desulfurization and denitrogenation were systematically investigated by analyzing the chars and tars from copyrolysis of Yanzhou high sulfur bituminous coal with coke-oven gas (COG), synthesis gas (SG) and hydrogen. The results indicated that under the conditions of 3MPa, up to 650{degree}C with a heating rate of 10{degree}C/min, the desulfurization of coal pyrolysis with COG, SG and hydrogen were almost equal (about 80%, w%, ad), the order of denitrogenation were: hydrogen (41%) {gt} SG(35%) {gt} COG(30%). The distributions of sulfur in char, oil and gas was very similar under the three reactive gases, i.e., about 205 in char, 105 in tar and 70% (diff.) in gas, respectively. Compared with hydropyrolysis at the same hydrogen partial pressure, the desulfurization of coal pyrolysis with coke oven gas was increased by about 4.5%, while the denitrogenation was decreased by about 3.5%. There is an important desulfurization advantage for hydropyrolysis using COG and SG instead of pure hydrogen. Compared with the copyrolysis of coal with COG, Yanzhou coal pyrolysis under SG can achieve the same level of desufurization but higher denitrogenation. 11 refs., 3 figs., 4 tabs.

Condensation in gas transmission pipelines. Phase behavior of mixtures of hydrogen with natural gas

Energy Technology Data Exchange (ETDEWEB)

Schouten, J.A.; Michels, J.P.J. [Amsterdam Univ. (Netherlands). Van der Waals-Zeeman Inst.; Rosmalen, R.J. van [Energy, Roden (Netherlands)

2005-05-01

Several pressure and temperature reductions occur along gas transmission lines. Since the pressure and temperature conditions of the natural gas in the pipeline are often close to the dew point curve, liquid dropout can occur. Injection of hydrogen into the natural gas will change the phase envelope and thus the liquid dropout. This condensation of the heavy hydrocarbons requires continuous operational attention and a positive effect of hydrogen may affect the decision to introduce hydrogen. In this paper we report on calculations of the amount of condensate in a natural gas and in this natural gas mixed with 16.7% hydrogen. These calculations have been performed at conditions prevailing in gas transport lines. The results will be used to discuss the difference in liquid dropout in a natural gas and in a mixture with hydrogen at pressure reduction stations, at crossings under waterways, at side-branching, and at separators in the pipelines. (author)

Hydrogen-rich saline protects retina against glutamate-induced excitotoxic injury in guinea pig.

Science.gov (United States)

Wei, Lihua; Ge, Li; Qin, Shucun; Shi, Yunzhi; Du, Changqing; Du, Hui; Liu, Liwei; Yu, Yang; Sun, Xuejun

2012-01-01

Molecular hydrogen (H(2)) is an efficient antioxidant that can selectively reduce hydroxyl radicals and inhibit oxidative stress-induced injuries. We investigated the protective effects and mechanism of hydrogen-rich saline in a glutamate-induced retinal injury model. Retinal excitotoxicity was induced in healthy guinea pigs by injecting glutamate into the vitreous cavity. After 30 min, hydrogen-rich saline was injected into the vitreous cavity, the peritoneal cavity or both. Seven days later, the retinal stress response was evaluated by examining the stress biomarkers, inducible nitric-oxide synthase (iNOS) and glucose-regulated protein 78 (GRP78). The impaired glutamate uptake was assessed by the expression of the excitatory amino acid transporter 1(EAAT-1). The retinal histopathological changes were investigated, focusing on the thicknesses of the entire retina and its inner layer, the number of cells in the retinal ganglion cell layer (GCL) and the ultrastructure of the retinal ganglion cells (RGCs) and glial cells. Compared with the glutamate-induced injury group, the hydrogen-rich saline treatment reduced the loss of cells in the GCL and thinning of the retina and attenuated cellular morphological damage. These improvements were greatest in animals that received H(2) injections into both the vitreous and the peritoneal cavities. The hydrogen-rich saline also inhibited the expression of glial fibrillary acidic protein (GFAP) in Müller cells, CD11b in microglia, and iNOS and GRP78 in glial cells. Moreover, the hydrogen-rich saline increased the expression of EAAT-1. In conclusion, the administration of hydrogen-rich saline through the intravitreal or/and intraperitoneal routes could reduce the retinal excitotoxic injury and promote retinal recovery. This result likely occurs by inhibiting the activation of glial cells, decreasing the production of the iNOS and GRP78 and promoting glutamate clearance. Copyright © 2011 Elsevier Ltd. All rights reserved.

Estimation of the hydrogen concentration in rat tissue using an airtight tube following the administration of hydrogen via various routes.

Science.gov (United States)

Liu, Chi; Kurokawa, Ryosuke; Fujino, Masayuki; Hirano, Shinichi; Sato, Bunpei; Li, Xiao-Kang

2014-06-30

Hydrogen exerts beneficial effects in disease animal models of ischemia-reperfusion injury as well as inflammatory and neurological disease. Additionally, molecular hydrogen is useful for various novel medical and therapeutic applications in the clinical setting. In the present study, the hydrogen concentration in rat blood and tissue was estimated. Wistar rats were orally administered hydrogen super-rich water (HSRW), intraperitoneal and intravenous administration of hydrogen super-rich saline (HSRS), and inhalation of hydrogen gas. A new method for determining the hydrogen concentration was then applied using high-quality sensor gas chromatography, after which the specimen was prepared via tissue homogenization in airtight tubes. This method allowed for the sensitive and stable determination of the hydrogen concentration. The hydrogen concentration reached a peak at 5 minutes after oral and intraperitoneal administration, compared to 1 minute after intravenous administration. Following inhalation of hydrogen gas, the hydrogen concentration was found to be significantly increased at 30 minutes and maintained the same level thereafter. These results demonstrate that accurately determining the hydrogen concentration in rat blood and organ tissue is very useful and important for the application of various novel medical and therapeutic therapies using molecular hydrogen.

Estimation of the hydrogen concentration in rat tissue using an airtight tube following the administration of hydrogen via various routes

Science.gov (United States)

Liu, Chi; Kurokawa, Ryosuke; Fujino, Masayuki; Hirano, Shinichi; Sato, Bunpei; Li, Xiao-Kang

2014-01-01

Hydrogen exerts beneficial effects in disease animal models of ischemia-reperfusion injury as well as inflammatory and neurological disease. Additionally, molecular hydrogen is useful for various novel medical and therapeutic applications in the clinical setting. In the present study, the hydrogen concentration in rat blood and tissue was estimated. Wistar rats were orally administered hydrogen super-rich water (HSRW), intraperitoneal and intravenous administration of hydrogen super-rich saline (HSRS), and inhalation of hydrogen gas. A new method for determining the hydrogen concentration was then applied using high-quality sensor gas chromatography, after which the specimen was prepared via tissue homogenization in airtight tubes. This method allowed for the sensitive and stable determination of the hydrogen concentration. The hydrogen concentration reached a peak at 5 minutes after oral and intraperitoneal administration, compared to 1 minute after intravenous administration. Following inhalation of hydrogen gas, the hydrogen concentration was found to be significantly increased at 30 minutes and maintained the same level thereafter. These results demonstrate that accurately determining the hydrogen concentration in rat blood and organ tissue is very useful and important for the application of various novel medical and therapeutic therapies using molecular hydrogen. PMID:24975958

Hydrogen-rich saline injection into the subarachnoid cavity within 2 weeks promotes recovery after acute spinal cord injury

Directory of Open Access Journals (Sweden)

Jian-long Wang

2015-01-01

Full Text Available Hydrogen can relieve tissue-damaging oxidative stress, inflammation and apoptosis. Injection of hydrogen-rich saline is an effective method for transporting molecular hydrogen. We hypothesized that hydrogen-rich saline would promote the repair of spinal cord injury induced by Allen′s method in rats. At 0.5, 1, 2, 4, 8, 12 and 24 hours after injury, then once daily for 2 weeks, 0.25 mL/kg hydrogen-rich saline was infused into the subarachnoid space through a catheter. Results at 24 hours, 48 hours, 1 week and 2 weeks after injury showed that hydrogen-rich saline markedly reduced cell death, inflammatory cell infiltration, serum malondialdehyde content, and caspase-3 immunoreactivity, elevated serum superoxide dismutase activity and calcitonin gene-related peptide immunoreactivity, and improved motor function in the hindlimb. The present study confirms that hydrogen-rich saline injected within 2 weeks of injury effectively contributes to the repair of spinal cord injury in the acute stage.

Therapeutic Effects of Hydrogen-Rich Solution on Aplastic Anemia in Vivo

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Sanhu Zhao

2013-08-01

Full Text Available Background: Aplasitc anemia (AA is a bone marrow failure syndrome characterized by an immune-mediated destruction of hematopoietic stem cells. Though clinical symptoms could be ameliorated by bone marrow transplantation and/or immunosuppressive therapy, frequent recurrence and especially evolution of clonal hematologic diseases remains problematic clinically. Cytokines such as interferon-γ (INF-γ, tumor necrosis factor-α (TNF-α and interleukin-6 (IL-6 secreted by autologous T cells are closely related with the development of AA. Hydrogen-rich solution was reported to inhibit the levels of cytokines including INF-γ, TNF-α and IL-6 in vivo in recent studies. This study was to investigate the potential therapeutic effects of hydrogen-rich solution on AA in vivo. Methods: AA model was determined in vivo by mice and body weights of the mice were used as the basic physiological index. Peripheral blood cells were calculated to evaluate the hematologic recovery degree. Bone marrow nucleated cells (BMNCs, tissue histology, as well as CFU-S and CFU-GM forming units were used to evaluate the recovery of bone marrow microenvironment. The ratio of CD4+ and CD8+ cells were examined along with cytokine levels in serum to determine the efficacy of H2-rich solution on the affected immunological functions. Results: Body weight and number of peripheral blood cells were significantly improved for mice in the H2-rich solution treated groups as compared with those with AA. The number of BMNCs and CFUs increased markedly and the bone marrow microenvironment was also improved significantly. The experimental group restrained the cell apoptosis, relieved hyperemia and accelerated tissue repair. The number of CD4+ and CD8+ cells as well as the ratio of CD4/CD8 increased to normal gradually, while the levels of TNF-α, IFN-γ, and IL-6 in serum decreased after H2-rich solution treatment. Conclusion: Our study firstly showed that hydrogen-rich solution accelerated the

The hydrogen economy - an opportunity for gas

International Nuclear Information System (INIS)

Soederbaum, J.; Martin, G.; O'Neill, C.

2003-01-01

Natural gas could play a pivotal role in any transition to a hydrogen economy-that is one of the findings of the recently-released National Hydrogen Study, commissioned by the Commonwealth Department of Industry, Tourism and Resources, and undertaken by the consulting firms ACIL Tasman and Parsons Brinckerhoff. The key benefits of hydrogen include zero emissions at the point of combustion (water is the main by-product) and its abundance Hydrogen can be produced from a range of primary energy sources including gas and coal, or through the electrolysis of water. Depending on the process used to manufacture hydrogen (especially the extent to which any associated carbon can be captured and sequestered), life-cycle emissions associated with its production and use can be reduced or entirely eliminated

Tritium removal by hydrogen isotopic exchange between hydrogen gas and water on hydrophobic catalyst

International Nuclear Information System (INIS)

Morishita, T.; Isomura, S.; Izawa, H.; Nakane, R.

1980-01-01

Many kinds of the hydrophobic catalysts for hydrogen isotopic exchange between hydrogen gas and water have been prepared. The carriers are the hydrophobic organic materials such as polytetrafluoroethylene(PTFE), monofluorocarbon-PTFE mixture(PTFE-FC), and styrene-divinylbenzene copolymer(SDB). 0.1 to 2 wt % Pt is deposited on the carriers. The Pt/SDB catalyst has much higher activity than the Pt/PTFE catalyst and the Pt/PTFE-FC catalyst shows the intermediate value of catalytic activity. The observation of electron microscope shows that the degrees of dispersion of Pt particles on the hydrophobic carriers result in the difference of catalytic activities. A gas-liquid separated type column containing ten stages is constructed. Each stage is composed of both the hydrophobic catalyst bed for the hydrogen gas/water vapor isotopic exchange and the packed column type bed for the water vapor/liquid water isotopic exchange. In the column hydrogen gas and water flow countercurrently and hydrogen isotopes are separated

Air gasification of empty fruit bunch for hydrogen-rich gas production in a fluidized-bed reactor

International Nuclear Information System (INIS)

Mohammed, M.A.A.; Salmiaton, A.; Wan Azlina, W.A.K.G.; Mohammad Amran, M.S.; Fakhru'l-Razi, A.

2011-01-01

A study on gasification of empty fruit bunch (EFB), a waste of the palm oil industry, was investigated. The composition and particle size distribution of feedstock were determined and the thermal degradation behaviour was analysed by a thermogravimetric analysis (TGA). Then fluidized bed bench scale gasification unit was used to investigate the effect of the operating parameters on EFB air gasification namely reactor temperature in the range of 700-1000 o C, feedstock particle size in the range of 0.3-1.0 mm and equivalence ratio (ER) in the range of 0.15-0.35. The main gas species generated, as identified by a gas chromatography (GC), were H 2 , CO, CO 2 and CH 4 . With temperature increasing from 700 o C to 1000 o C, the total gas yield was enhanced greatly and reached the maximum value (∼92 wt.%, on the raw biomass sample basis) at 1000 o C with big portions of H 2 (38.02 vol.%) and CO (36.36 vol.%). Feedstock particle size showed an influence on the upgrading of H 2 , CO and CH 4 yields. The feedstock particle size of 0.3-0.5 mm, was found to obtain a higher H 2 yield (33.93 vol.%), and higher LHV of gas product (15.26 MJ/m 3 ). Equivalence ratio (ER) showed a significant influence on the upgrading of hydrogen production and product distribution. The optimum ER (0.25) was found to attain a higher H 2 yield (27.31 vol.%) at 850 o C. Due to the low efficiency of bench scale gasification unit the system needs to be scaling-up. The cost analysis for scale-up EFB gasification unit showed that the hydrogen supply cost is RM 6.70/kg EFB ($2.11/kg = $0.18/Nm 3 ).

Plasma promoted manufacturing of hydrogen and vehicular applications

Science.gov (United States)

Bromberg, Leslie

2003-10-01

Plasmas can be used for promoting reformation of fuels. Plasma-based reformers developed at MIT use a low temperature, low power, low current electrical discharge to promote partial oxidation conversion of hydrocarbon fuels into hydrogen and CO. The very fuel rich mixture is hard to ignite, and the plasmatron provides a volume-ignition. To minimize erosion and to simplify the power supply, a low current high voltage discharge is used, with wide area electrodes. The plasmatron fuel reformer operates at or slightly above atmospheric pressure. The plasma-based reformer technology provides the advantages of rapid startup and transient response; efficient conversion of the fuel to hydrogen rich gas; compact size; relaxation or elimination of reformer catalyst requirements; and capability to process difficult to reform fuels. These advantages enable use of hydrogen-manufacturing reformation technology in cars using available fuels, such as gasoline and diesel. This plasma-based reformer technology can provide substantial throughputs even without the use of a catalyst. The electrical power consumption of the device is minimized by design and operational characteristics (less than 500 W peak and 200 W average). The product from these plasma reactors is a hydrogen rich mixture that can be used for combustion enhancement and emissions aftertreatment in vehicular applications. By converting a small fraction of the fuel to hydrogen rich gas, in-cylinder combustion can be improved. With minor modification of the engine, use of hydrogen rich gas results in increased fuel efficiency and decreased emissions of smog producing gases. The status of plasma based reformer technology and its application to vehicles will be described.

Two-stage coal liquefaction without gas-phase hydrogen

Science.gov (United States)

Stephens, H.P.

1986-06-05

A process is provided for the production of a hydrogen-donor solvent useful in the liquefaction of coal, wherein the water-gas shift reaction is used to produce hydrogen while simultaneously hydrogenating a donor solvent. A process for the liquefaction of coal using said solvent is also provided. The process enables avoiding the use of a separate water-gas shift reactor as well as high pressure equipment for liquefaction. 3 tabs.

Method of controlling injection of oxygen into hydrogen-rich fuel cell feed stream

Science.gov (United States)

Meltser, Mark Alexander; Gutowski, Stanley; Weisbrod, Kirk

2001-01-01

A method of operating a H.sub.2 --O.sub.2 fuel cell fueled by hydrogen-rich fuel stream containing CO. The CO content is reduced to acceptable levels by injecting oxygen into the fuel gas stream. The amount of oxygen injected is controlled in relation to the CO content of the fuel gas, by a control strategy that involves (a) determining the CO content of the fuel stream at a first injection rate, (b) increasing the O.sub.2 injection rate, (c) determining the CO content of the stream at the higher injection rate, (d) further increasing the O.sub.2 injection rate if the second measured CO content is lower than the first measured CO content or reducing the O.sub.2 injection rate if the second measured CO content is greater than the first measured CO content, and (e) repeating steps a-d as needed to optimize CO consumption and minimize H.sub.2 consumption.

Hydrogen-rich saline ameliorates the severity of L-arginine-induced acute pancreatitis in rats

International Nuclear Information System (INIS)

Chen, Han; Sun, Yan Ping; Li, Yang; Liu, Wen Wu; Xiang, Hong Gang; Fan, Lie Ying; Sun, Qiang; Xu, Xin Yun; Cai, Jian Mei; Ruan, Can Ping; Su, Ning; Yan, Rong Lin; Sun, Xue Jun; Wang, Qiang

2010-01-01

Molecular hydrogen, which reacts with the hydroxyl radical, has been considered as a novel antioxidant. Here, we evaluated the protective effects of hydrogen-rich saline on the L-arginine (L-Arg)-induced acute pancreatitis (AP). AP was induced in Sprague-Dawley rats by giving two intraperitoneal injections of L-Arg, each at concentrations of 250 mg/100 g body weight, with an interval of 1 h. Hydrogen-rich saline (>0.6 mM, 6 ml/kg) or saline (6 ml/kg) was administered, respectively, via tail vein 15 min after each L-Arg administration. Severity of AP was assessed by analysis of serum amylase activity, pancreatic water content and histology. Samples of pancreas were taken for measuring malondialdehyde and myeloperoxidase. Apoptosis in pancreatic acinar cell was determined with terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling technique (TUNEL). Expression of proliferating cell nuclear antigen (PCNA) and nuclear factor kappa B (NF-κB) were detected with immunohistochemistry. Hydrogen-rich saline treatment significantly attenuated the severity of L-Arg-induced AP by ameliorating the increased serum amylase activity, inhibiting neutrophil infiltration, lipid oxidation and pancreatic tissue edema. Moreover, hydrogen-rich saline treatment could promote acinar cell proliferation, inhibit apoptosis and NF-κB activation. These results indicate that hydrogen treatment has a protective effect against AP, and the effect is possibly due to its ability to inhibit oxidative stress, apoptosis, NF-κB activation and to promote acinar cell proliferation.

Steam gasification of rapeseed, wood, sewage sludge and miscanthus biochars for the production of a hydrogen-rich syngas

International Nuclear Information System (INIS)

Sattar, Anwar; Leeke, Gary A.; Hornung, Andreas; Wood, Joseph

2014-01-01

Steam gasification of biochars has emerged as a promising method for generating syngas that is rich in hydrogen. In this study four biochars formed via intermediate pyrolysis (wood pellet, sewage sludge, rapeseed and miscanthus) were gasified in a quartz tubular reactor using steam. The dynamic behaviour of the process and effects of temperature, steam flow and particle size were studied. The results show that increases in both steam flow and temperature significantly increase the dry gas yield and carbon conversion, but hydrogen volume fraction decreases at higher temperatures whilst particle size has little effect on gaseous composition. The highest volume fraction of hydrogen, 58.7%, was obtained at 750 °C from the rapeseed biochar. - Highlights: • Four biochars from intermediate pyrolysis were gasified. • High hydrogen concentration was achieved in all cases. • Peak hydrogen was 165 mg min −1  g −1 biochar at 700–750 °C. • High mineral content biochars had the highest reactivities. • Varying particle size had very little effect on gaseous composition

Hyperoxygenated hydrogen-rich solution suppresses shock- and resuscitation-induced liver injury.

Science.gov (United States)

Dang, Yangjie; Liu, Ting; Mei, Xiaopeng; Meng, Xiangzhong; Gou, Xingchun; Deng, Bin; Xu, Hao; Xu, Lixian

2017-12-01

It is not known whether simultaneous delivery of hydrogen and oxygen can reduce injury caused by hemorrhagic shock and resuscitation (HSR). This study investigated the therapeutic potential of hyperoxygenated hydrogen-rich solution (HHOS), a combined hydrogen/oxygen carrier, in a rat model of HSR-induced liver injury. Rats (n = 60) were randomly divided into 5 groups (n = 6 per group at each time point). One group underwent sham operation, and the others were subjected to severe hemorrhagic shock and then treated with lactated Ringer's solution (LRS), hydrogen-rich solution, hyperoxygenated solution, or HHOS. At 2 and 6 h after resuscitation, blood samples (n = 6) were collected from the femoral artery and serum concentrations of alanine aminotransferase and aspartate aminotransferase (AST) were measured. Rats were then sacrificed, and histopathological changes in the liver were evaluated by quantifying the percentage of apoptotic cells by caspase-3 immunohistochemistry and terminal deoxynucleotidyl transferase dUTP nick-end labeling. Inflammation was assessed by assessing malondialdehyde content and tumor necrosis factor-α, and interleukin (IL)-6 expression. Compared to lactated Ringer's solution, hydrogen-rich solution, or hyperoxygenated solution groups, serum AST and alanine aminotransferase levels and IL-6, tumor necrosis factor-α, and malondialdehyde expression in liver tissue were decreased by HHOS treatment. The number of caspase-3- and terminal deoxynucleotidyl transferase dUTP nick end labeling-positive cells was decreased (P < 0.05) by HHOS treatment, 2 and 6 h after resuscitation. HHOS has protective effects against liver injury in a rat model of HSR. Copyright © 2017 Elsevier Inc. All rights reserved.

A new technique for pumping hydrogen gas

Science.gov (United States)

Friedman, I.; Hardcastle, K.

1970-01-01

A system for pumping hydrogen gas without isotopic fractionation has been developed. The pump contains uranium metal, which when heated to about 80??C reacts with hydrogen to form UH3. The UH3 is heated to above 500??C to decompose the hydride and regenerate the hydrogen. ?? 1970.

Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

Energy Technology Data Exchange (ETDEWEB)

John Pratapas; Daniel Mather; Anton Kozlovsky

2007-03-31

analysis of test results indicates that hydrogen enhanced natural gas HCCI (versus neat natural gas HCCI at comparable stoichiometry) had the following characteristics: (1) Substantially lower intake temperature needed for stable HCCI combustion; (2) Inconclusive impact on engine BMEP and power produced; (3) Small reduction in the thermal efficiency of the engine; (4) Moderate reduction in the unburned hydrocarbons in the exhaust; (5) Slight increase in NOx emissions in the exhaust; (6) Slight reduction in CO2 in the exhaust; and (7) Increased knocking at rich stoichiometry. The major accomplishments and findings from the project can be summarized as follows: (1) A model was calibrated for accurately predicting heat release rate and peak pressures for HCCI combustion when operating on hydrogen and natural gas blends. (2) A single cylinder research engine was thoroughly mapped to compare performance and emissions for micro-pilot natural gas compression ignition, and HCCI combustion for neat natural gas versus blends of natural gas and hydrogen. (3) The benefits of using hydrogen to extend, up to a limit, the stable operating window for HCCI combustion of natural gas at higher intake pressures, leaner air to fuel ratios or lower inlet temperatures was documented.

Recovery of krypton-85 from dissolver off-gas streams

International Nuclear Information System (INIS)

Law, J.P.; Lamb, K.M.

1988-01-01

The Rare Gas Plant at the Idaho Chemical Processing Plant Recovers fission product krypton and xenon from dissolver off gas streams. Recently the system was upgraded to allow processing of hydrogen rich dissolver off-gas streams. A trickle bed hydrogen recombiner was installed and tested. The Rare Gas Plant can now safely process gas streams containing up to 80% hydrogen

Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

Energy Technology Data Exchange (ETDEWEB)

Pratapas, John; Mather, Daniel; Kozlovsky, Anton

2013-03-31

analysis of test results indicates that hydrogen enhanced natural gas HCCI (versus neat natural gas HCCI at comparable stoichiometry) had the following characteristics: • Substantially lower intake temperature needed for stable HCCI combustion • Inconclusive impact on engine BMEP and power produced, • Small reduction in the thermal efficiency of the engine, • Moderate reduction in the unburned hydrocarbons in the exhaust, • Slight increase in NOx emissions in the exhaust, • Slight reduction in CO2 in the exhaust. • Increased knocking at rich stoichiometry The major accomplishments and findings from the project can be summarized as follows: 1. A model was calibrated for accurately predicting heat release rate and peak pressures for HCCI combustion when operating on hydrogen and natural gas blends. 2. A single cylinder research engine was thoroughly mapped to compare performance and emissions for micro-pilot natural gas compression ignition, and HCCI combustion for neat natural gas versus blends of natural gas and hydrogen.

Gas-rich dwarfs and accretion phenomena in early-type galaxies

Science.gov (United States)

Silk, J.; Norman, C.

1979-01-01

An analysis is presented of the combined effects of cloud accretion and galactic winds and coronae. An accretion model is developed wherein gas-rich dwarf galaxies are accreted into galactic halos, which provides an adequate source of H I to account for observations of neutral gas in early-type galaxies. Accretion is found to fuel the wind, thereby regulating the accretion flow and yielding a time-dependent model for star formation, enrichment, and nuclear activity. The permissible parameter range for intergalactic gas clouds and galaxy groups is discussed, along with the frequency of gas-rich dwarfs and their large ratios of gas mass to luminosity. Also considered is the occurrence of gas stripping and the consequent formation of dwarf spheroidal systems that remain in the halo, and gas clouds that dissipate and suffer further infall. A cosmological implication of the model is that, because the characteristic time scale of a gas-rich dwarf galaxy to be accreted and lose its gas is comparable to a Hubble time, there may have been a far more extensive primordial distribution of such systems at earlier epochs.

Effectiveness of hydrogen rich water on antioxidant status of subjects with potential metabolic syndrome-an open label pilot study.

Science.gov (United States)

Nakao, Atsunori; Toyoda, Yoshiya; Sharma, Prachi; Evans, Malkanthi; Guthrie, Najla

2010-03-01

Metabolic syndrome is characterized by cardiometabolic risk factors that include obesity, insulin resistance, hypertension and dyslipidemia. Oxidative stress is known to play a major role in the pathogenesis of metabolic syndrome. The objective of this study was to examine the effectiveness of hydrogen rich water (1.5-2 L/day) in an open label, 8-week study on 20 subjects with potential metabolic syndrome. Hydrogen rich water was produced, by placing a metallic magnesium stick into drinking water (hydrogen concentration; 0.55-0.65 mM), by the following chemical reaction; Mg + 2H(2)O --> Mg (OH)(2) + H(2). The consumption of hydrogen rich water for 8 weeks resulted in a 39% increase (pfasting glucose levels during the 8 week study. In conclusion, drinking hydrogen rich water represents a potentially novel therapeutic and preventive strategy for metabolic syndrome. The portable magnesium stick was a safe, easy and effective method of delivering hydrogen rich water for daily consumption by participants in the study.

Role of a natural gas utility in the hydrogen economy

International Nuclear Information System (INIS)

Bayko, J.

2004-01-01

'Full text:' Enbridge Gas Distribution is the largest natural gas distribution company in Canada at about 1.7 million residential, commercial and industrial customers. Enbridge will speak to the role of a natural gas utility in the hydrogen economy, and outline the benefits of hydrogen production from natural gas reformation for both stationary and mobile applications. Hydrocarbon reformation will act at least as a bridge until a more fully developed hydrogen economy infrastructure is developed. Reformation allows immediate leveraging of the reliability of vast existing natural gas distribution systems, and a reduced need for on-site hydrogen storage. Natural gas powered fuel cells provide improved emissions over traditional internal combustion engines, and in the stationary market provide smarter use of resources through the higher efficiencies of cogeneration (the capture and use of otherwise waste heat). (author)

Performance simulation of planar SOFC using mixed hydrogen and carbon monoxide gases as fuel

Energy Technology Data Exchange (ETDEWEB)

Inui, Y. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan)]. E-mail: inui@eee.tut.ac.jp; Urata, A. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan); Ito, N. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan); Nakajima, T. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan); Tanaka, T. [Department of Electrical and Electronic Engineering, Toyohashi University of Technology, Tempaku-cho, Toyohashi 441-8580 (Japan)

2006-08-15

The authors investigate in detail the influence of the mixing ratio of hydrogen and carbon monoxide in the fuel on the cell performance of the SOFC through numerical simulations for a single cell plate of the co-flow type planar cell. It is made clear that the cell performance is almost the same and excellent, independent of the mixing ratio of hydrogen and carbon monoxide under the nominal operating condition. The electromotive force of the hydrogen rich fuel gas is a little higher than that of the carbon monoxide rich fuel gas. The internal voltage drop in the cell decreases as the fraction of carbon monoxide becomes high. Since the value of the single cell voltage is determined by the balance of these two phenomena, the lowering of the electromotive force is dominant and the single cell voltage of the hydrogen rich fuel gas is higher when the inlet gas temperature is high, whereas the voltage drop reduction is dominant and the single cell voltage of the carbon monoxide rich fuel gas is higher when the temperature is low. The effect of the additional gases of water vapor and carbon dioxide is restricted to the single cell voltage shift, and the qualitative dependence of the single cell voltage on the inlet gas temperature is determined by the mixing ratio of hydrogen and carbon monoxide.

Performance simulation of planar SOFC using mixed hydrogen and carbon monoxide gases as fuel

International Nuclear Information System (INIS)

Inui, Y.; Urata, A.; Ito, N.; Nakajima, T.; Tanaka, T.

2006-01-01

The authors investigate in detail the influence of the mixing ratio of hydrogen and carbon monoxide in the fuel on the cell performance of the SOFC through numerical simulations for a single cell plate of the co-flow type planar cell. It is made clear that the cell performance is almost the same and excellent, independent of the mixing ratio of hydrogen and carbon monoxide under the nominal operating condition. The electromotive force of the hydrogen rich fuel gas is a little higher than that of the carbon monoxide rich fuel gas. The internal voltage drop in the cell decreases as the fraction of carbon monoxide becomes high. Since the value of the single cell voltage is determined by the balance of these two phenomena, the lowering of the electromotive force is dominant and the single cell voltage of the hydrogen rich fuel gas is higher when the inlet gas temperature is high, whereas the voltage drop reduction is dominant and the single cell voltage of the carbon monoxide rich fuel gas is higher when the temperature is low. The effect of the additional gases of water vapor and carbon dioxide is restricted to the single cell voltage shift, and the qualitative dependence of the single cell voltage on the inlet gas temperature is determined by the mixing ratio of hydrogen and carbon monoxide

Large Eddy Simulation Modeling of Flashback and Flame Stabilization in Hydrogen-Rich Gas Turbines Using a Hierarchical Validation Approach

Energy Technology Data Exchange (ETDEWEB)

Clemens, Noel [Univ. of Texas, Austin, TX (United States)

2015-09-30

This project was a combined computational and experimental effort to improve predictive capability for boundary layer flashback of premixed swirl flames relevant to gas-turbine power plants operating with high-hydrogen-content fuels. During the course of this project, significant progress in modeling was made on four major fronts: 1) use of direct numerical simulation of turbulent flames to understand the coupling between the flame and the turbulent boundary layer; 2) improved modeling capability for flame propagation in stratified pre-mixtures; 3) improved portability of computer codes using the OpenFOAM platform to facilitate transfer to industry and other researchers; and 4) application of LES to flashback in swirl combustors, and a detailed assessment of its capabilities and limitations for predictive purposes. A major component of the project was an experimental program that focused on developing a rich experimental database of boundary layer flashback in swirl flames. Both methane and high-hydrogen fuels, including effects of elevated pressure (1 to 5 atm), were explored. For this project, a new model swirl combustor was developed. Kilohertz-rate stereoscopic PIV and chemiluminescence imaging were used to investigate the flame propagation dynamics. In addition to the planar measurements, a technique capable of detecting the instantaneous, time-resolved 3D flame front topography was developed and applied successfully to investigate the flow-flame interaction. The UT measurements and legacy data were used in a hierarchical validation approach where flows with increasingly complex physics were used for validation. First component models were validated with DNS and literature data in simplified configurations, and this was followed by validation with the UT 1-atm flashback cases, and then the UT high-pressure flashback cases. The new models and portable code represent a major improvement over what was available before this project was initiated.

Process for the production of hydrogen/deuterium-containing gas

International Nuclear Information System (INIS)

Nitschke, E.; Desai, A.; Ilgner, H.

1978-01-01

A process for the production of hydrogen/deuterium-containing gas is described in which the enriched condensate obtained from the production of a hydrogen/deuterium-containing gas mixture is collected and subjected to a direct exchange of isotopes with the feedsteam admitted to the process. Such condensate can be brought into direct exchange of isotopes with the gas water vapor mixture within the process, viz. ahead of the CO conversion section. The exchange of isotopes may be performed according to the counter-current principle. If it is intended to maintain in the hydrogen/deuterium-containing gas a certain definite content of water vapor whose phase condition is superior to the condition achieved when using normal cooling water, this gas, at least 0.6 kg/m 3 of gas, is subjected to an exchange of isotopes with the water fed additionally into the process

Silicon Carbide-Based Hydrogen Gas Sensors for High-Temperature Applications

Directory of Open Access Journals (Sweden)

Sangchoel Kim

2013-10-01

Full Text Available We investigated SiC-based hydrogen gas sensors with metal-insulator-semiconductor (MIS structure for high temperature process monitoring and leak detection applications in fields such as the automotive, chemical and petroleum industries. In this work, a thin tantalum oxide (Ta2O5 layer was exploited with the purpose of sensitivity improvement, because tantalum oxide has good stability at high temperature with high permeability for hydrogen gas. Silicon carbide (SiC was used as a substrate for high-temperature applications. We fabricated Pd/Ta2O5/SiC-based hydrogen gas sensors, and the dependence of their I-V characteristics and capacitance response properties on hydrogen concentrations were analyzed in the temperature range from room temperature to 500 °C. According to the results, our sensor shows promising performance for hydrogen gas detection at high temperatures.

Development Of A Centrifugal Hydrogen Pipeline Gas Compressor

Energy Technology Data Exchange (ETDEWEB)

Di Bella, Francis A. [Concepts NREC, White River Junction, VY (United States)

2015-04-16

Concepts NREC (CN) has completed a Department of Energy (DOE) sponsored project to analyze, design, and fabricate a pipeline capacity hydrogen compressor. The pipeline compressor is a critical component in the DOE strategy to provide sufficient quantities of hydrogen to support the expected shift in transportation fuels from liquid and natural gas to hydrogen. The hydrogen would be generated by renewable energy (solar, wind, and perhaps even tidal or ocean), and would be electrolyzed from water. The hydrogen would then be transported to the population centers in the U.S., where fuel-cell vehicles are expected to become popular and necessary to relieve dependency on fossil fuels. The specifications for the required pipeline hydrogen compressor indicates a need for a small package that is efficient, less costly, and more reliable than what is available in the form of a multi-cylinder, reciprocating (positive displacement) compressor for compressing hydrogen in the gas industry.

Experimental study on flame propagation characteristics of Hydrogen premixed gas in gas pipeline

Science.gov (United States)

Ma, Danzhu; Li, Zhuang; Jia, Fengrui; Li, Zhou

2018-06-01

Hydrogen is the cleanest high-energy gas fuel, and also is the main industrial material. However, hydrogen is more explosive and more powerful than conventional gas fuels, which restricts its application. In particular, the expansion of premixed combustion under a strong constraint is more complicated, the reaction spreads faster. The flame propagation characteristics of premixed hydrogen/air were investigated by experiment. The mechanism of reaction acceleration is discussed, and then the speed of the flame propagation and the reaction pressure were tested and analysed.

Microwave interaction with nonuniform hydrogen gas in carbon nanotubes

International Nuclear Information System (INIS)

Babaei, S.; Babaei, Sh.

2009-01-01

In this paper we study the reflection, absorption, and transmission of microwave from nonuniform hydrogen gas in carbon nanotubes, grown by iron-catalyzed high-pressure carbon monoxide disproportionate (HiPco) process. A discussion on the effect of various hydrogen gas parameters on the reflected power, absorbed power, and transmitted power is presented. The nonuniform hydrogen gas slab is modeled by a series of subslabs. The overall number density profile across the whole slab follows a parabolic function. The total reflected, absorbed, and transmitted powers are then deduced and their functional dependence on the number density, collision frequency, and angle of propagation is studied

Field effect-gas sensor for hydrogen

Energy Technology Data Exchange (ETDEWEB)

Plihal, M [Siemens A.G., Muenchen (Germany, F.R.). Forschungslaboratorium

1977-01-01

MIS diodes with palladium gate can be used to detect and to measure quantitatively the hydrogen concentration in gas mixtures. The dependence of the differential capacitance of these diodes on the partial pressure of hydrogen in nitrogen, oxygen and air is investigated. A theoretical model is developed which gives satisfactory agreement with most of the experimental results.

Radiolytic and thermolytic bubble gas hydrogen composition

Energy Technology Data Exchange (ETDEWEB)

Woodham, W. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

2017-12-11

This report describes the development of a mathematical model for the estimation of the hydrogen composition of gas bubbles trapped in radioactive waste. The model described herein uses a material balance approach to accurately incorporate the rates of hydrogen generation by a number of physical phenomena and scale the aforementioned rates in a manner that allows calculation of the final hydrogen composition.

Zeolite Membrane Reactor for Water Gas Shift Reaction for Hydrogen Production

Energy Technology Data Exchange (ETDEWEB)

Lin, Jerry Y.S. [Arizona State Univ., Mesa, AZ (United States)

2013-01-29

Gasification of biomass or heavy feedstock to produce hydrogen fuel gas using current technology is costly and energy-intensive. The technology includes water gas shift reaction in two or more reactor stages with inter-cooling to maximize conversion for a given catalyst volume. This project is focused on developing a membrane reactor for efficient conversion of water gas shift reaction to produce a hydrogen stream as a fuel and a carbon dioxide stream suitable for sequestration. The project was focused on synthesizing stable, hydrogen perm-selective MFI zeolite membranes for high temperature hydrogen separation; fabricating tubular MFI zeolite membrane reactor and stable water gas shift catalyst for membrane reactor applications, and identifying experimental conditions for water gas shift reaction in the zeolite membrane reactor that will produce a high purity hydrogen stream. The project has improved understanding of zeolite membrane synthesis, high temperature gas diffusion and separation mechanisms for zeolite membranes, synthesis and properties of sulfur resistant catalysts, fabrication and structure optimization of membrane supports, and fundamentals of coupling reaction with separation in zeolite membrane reactor for water gas shift reaction. Through the fundamental study, the research teams have developed MFI zeolite membranes with good perm-selectivity for hydrogen over carbon dioxide, carbon monoxide and water vapor, and high stability for operation in syngas mixture containing 500 part per million hydrogen sulfide at high temperatures around 500°C. The research teams also developed a sulfur resistant catalyst for water gas shift reaction. Modeling and experimental studies on the zeolite membrane reactor for water gas shift reaction have demonstrated the effective use of the zeolite membrane reactor for production of high purity hydrogen stream.

Adsorption of hydrogen gas and redox processes in clays.

Science.gov (United States)

Didier, Mathilde; Leone, Laura; Greneche, Jean-Marc; Giffaut, Eric; Charlet, Laurent

2012-03-20

In order to assess the adsorption properties of hydrogen gas and reactivity of adsorbed hydrogen, we measured H(2)(g) adsorption on Na synthetic montmorillonite-type clays and Callovo-Oxfordian (COx) clayrock using gas chromatography. Synthetic montmorillonites with increasing structural Fe(III) substitution (0 wt %, 3.2 wt %, and 6.4 wt % Fe) were used. Fe in the synthetic montmorillonites is principally present as structural Fe(III) ions. We studied the concomitant reduction of structural Fe(III) in the clays using (57)Fe Mössbauer spectrometry. The COx, which mainly contains smectite/illite and calcite minerals, is also studied together with the pure clay fraction of this clayrock. Experiments were performed with dry clay samples which were reacted with hydrogen gas at 90 and 120 °C for 30 to 45 days at a hydrogen partial pressure close to 0.45 bar. Results indicate that up to 0.11 wt % of hydrogen is adsorbed on the clays at 90 °C under 0.45 bar of relative pressure. (57)Fe Mössbauer spectrometry shows that up to 6% of the total structural Fe(III) initially present in these synthetic clays is reduced upon adsorption of hydrogen gas. No reduction is observed with the COx sample in the present experimental conditions.

Blending Hydrogen into Natural Gas Pipeline Networks. A Review of Key Issues

Energy Technology Data Exchange (ETDEWEB)

Melaina, M. W. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Antonia, O. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Penev, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2013-03-01

This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building dedicated hydrogen pipelines. Blending hydrogen into the existing natural gas pipeline network has also been proposed as a means of increasing the output of renewable energy systems such as large wind farms.

Device to remove hydrogen isotopes from a gas phase

International Nuclear Information System (INIS)

Morlock, G.; Wiesemes, J.; Bachner, D.

1977-01-01

The device described here guarantees the selective removal of hydrogen isotopes from gas phases in order to prevent the occurence of explosive H 2 gas mixtures, or to separate off radioactive tritium in nuclear plants from the gas phase. It consists of a closed container whose walls are selectively penetrable by hydrogen isotopes. It is simultaneously filled compactly and presssure-resistant with a metal bulk (e.g. powder, sponges or the like of titanium or other hydrogen isotope binding metal). Walling and bulk are maintained at suitable working temperatures by means of a system according to the Peltier effect. The whole thing is safeguarded by protective walling. (RB) [de

Hydrogen-rich saline inhibits tobacco smoke-induced chronic obstructive pulmonary disease by alleviating airway inflammation and mucus hypersecretion in rats.

Science.gov (United States)

Liu, Zibing; Geng, Wenye; Jiang, Chuanwei; Zhao, Shujun; Liu, Yong; Zhang, Ying; Qin, Shucun; Li, Chenxu; Zhang, Xinfang; Si, Yanhong

2017-09-01

Chronic obstructive pulmonary disease induced by tobacco smoke has been regarded as a great health problem worldwide. The purpose of this study is to evaluate the protective effect of hydrogen-rich saline, a novel antioxidant, on chronic obstructive pulmonary disease and explore the underlying mechanism. Sprague-Dawley rats were made chronic obstructive pulmonary disease models via tobacco smoke exposure for 12 weeks and the rats were treated with 10 ml/kg hydrogen-rich saline intraperitoneally during the last 4 weeks. Lung function testing indicated hydrogen-rich saline decreased lung airway resistance and increased lung compliance and the ratio of forced expiratory volume in 0.1 s/forced vital capacity in chronic obstructive pulmonary disease rats. Histological analysis revealed that hydrogen-rich saline alleviated morphological impairments of lung in tobacco smoke-induced chronic obstructive pulmonary disease rats. ELISA assay showed hydrogen-rich saline lowered the levels of pro-inflammatory cytokines (IL-8 and IL-6) and anti-inflammatory cytokine IL-10 in bronchoalveolar lavage fluid and serum of chronic obstructive pulmonary disease rats. The content of malondialdehyde in lung tissue and serum was also determined and the data indicated hydrogen-rich saline suppressed oxidative stress reaction. The protein expressions of mucin MUC5C and aquaporin 5 involved in mucus hypersecretion were analyzed by Western blot and ELISA and the data revealed that hydrogen-rich saline down-regulated MUC5AC level in bronchoalveolar lavage fluid and lung tissue and up-regulated aquaporin 5 level in lung tissue of chronic obstructive pulmonary disease rats. In conclusion, these results suggest that administration of hydrogen-rich saline exhibits significant protective effect on chronic obstructive pulmonary disease through alleviating inflammation, reducing oxidative stress and lessening mucus hypersecretion in tobacco smoke-induced chronic obstructive pulmonary disease rats

Blending Hydrogen into Natural Gas Pipeline Networks: A Review of Key Issues

Energy Technology Data Exchange (ETDEWEB)

Melaina, M. W.; Antonia, O.; Penev, M.

2013-03-01

The United States has 11 distinct natural gas pipeline corridors: five originate in the Southwest, four deliver natural gas from Canada, and two extend from the Rocky Mountain region. This study assesses the potential to deliver hydrogen through the existing natural gas pipeline network as a hydrogen and natural gas mixture to defray the cost of building dedicated hydrogen pipelines.

Improvement of anaerobic bio-hydrogen gas production from organic sludge waste

International Nuclear Information System (INIS)

Lee, S.; Lee, Y. H.

2009-01-01

Microbial hydrogen gas production from organic matters stands out as one of the most promising alternatives for sustainable green energy production. Based on the literature review, investigation of anaerobic bio-hydrogen gas production from organic sludge waste using a mixed culture has been very limited. The objective of this study was to assess the anaerobic bio-hydrogen gas production from organic sludge waste under various conditions. (Author)

Process for hydrogen isotope exchange and concentration between liquid water and hydrogen gas and catalyst assembly therefor

International Nuclear Information System (INIS)

Stevens, W.H.

1975-01-01

A bithermal, catalytic, hydrogen isotope exchange process between liquid water and hydrogen gas to effect concentration of the deuterium isotope of hydrogen is described. Liquid water and hydrogen gas are contacted with one another and with at least one catalytically active metal selected from Group VIII of the Periodic Table; the catalyst body has a water repellent, gas and water vapor permeable, organic polymer or resin coating, preferably a fluorinated olefin polymer or silicone resin coating, so that the isotope exchange takes place by two simultaneously occurring, and closely coupled in space, steps and concentration is effected by operating two interconnected sections containing catalyst at different temperatures. (U.S.)

Potential application of gas chromatography to the analysis of hydrogen isotopes

International Nuclear Information System (INIS)

Warner, D.K.; Sprague, R.E.; Bohl, D.R.

1976-01-01

Gas chromatography is used at Mound Laboratory for the analysis of hydrogen isotopic impurities in gas mixtures. This instrumentation was used to study the applicability of the gas chromatography technique to the determination of the major components of hydrogen isotopic gas mixtures. The results of this study, including chromatograms and precision data, are presented

Method of removing hydrogen sulphide from hot gas mixtures

Energy Technology Data Exchange (ETDEWEB)

Furimsky, E.; Yumura, M.

1987-12-22

Hydrogen sulphide can be removed from hot gas mixtures by contacting the hot gas mixture at temperatures in the range of 500-900/sup 0/C with an adsorbent consisting of managanese nodules. The nodules may contain additional calcium cations. In sulphided form, the nodules are catalytically active for hydrogen sulphide decomposition to produce hydrogen. Regeneration of the adsorbent can be accomplished by roasting in an oxidizing atmosphere. The nodules can be used to treat gaseous mixtures containing up to 20% hydrogen sulfide, for example, gases produced during pyrolysis, cracking, coking, and hydrotreating processes. Experiments using the processes described in this patent are also outlined. 6 tabs.

Hydrogen-enriched natural gas; Bridge to an ultra low carbon world

Energy Technology Data Exchange (ETDEWEB)

Samuel, Joshua; Oliver, Mike

2010-09-15

Natural gas is recognized as an important part of the solution to climate change, as it has the smallest carbon footprint among fossil fuels and can be used with high efficiency. This alone is not enough. Supplementing natural gas with hydrogen creating hydrogen-enriched natural gas (HENG), where the hydrogen comes from a low- or zero-carbon energy source. HENG, the subject of this paper, can leverage existing natural gas infrastructure to reduce CO2 and NOx, improve the efficiency of end-use equipment, and lower the overall carbon intensity of energy consumption.

a Study of Using Hydrogen Gas for Steam Boiler in CHOLOR- Alkali Manufacturing

Science.gov (United States)

Peantong, Sasitorn; Tangjitsitcharoen, Somkiat

2017-06-01

Main products of manufacturing of Cholor - Alkali, which commonly known as industrial chemical, are chlorine gas (Cl2), Sodium Hydroxide (NaOH) and hydrogen gas (H2). Chorine gas and sodium hydroxide are two main products for commercial profit; where hydrogen gas is by product. Most industries release hydrogen gas to atmosphere as it is non-profitable and less commercial scale. This study aims to make the most use of hydrogen as a substitute energy of natural gas for steam boiler to save energy cost. The second target of this study is to reduce level of CO2 release to air as a consequence of boiler combustion. This study suggests to install boiler that bases on hydrogen as main power with a high turndown ratio of at least 1:6. However, this case study uses boiler with two mode such as natural gas (NG) mode and mixed mode as they need to be flexible for production. Never the less, the best boiler selection is to use single mode energy of hydrogen. The most concerned issue about hydrogen gas is explosion during combustion stage. Stabilization measures at emergency stop is introduced to control H2 pressure to protect the explosion. This study varies ratio of natural gas to hydrogen gas to find the optimal level of two energy sources for boiler and measure total consumption through costing model; where CO2 level is measured at the boiler stack. The result of this study shows that hydrogen gas can be a substitute energy with natural gas and can reduce cost. Natural gas cost saving is 248,846 baht per month and reduce level of NOx is 80 ppm 7% O2 and 2 % of CO2 release to air as a consequence of boiler combustion.

Protective Effects of Hydrogen-Rich Saline Against Lipopolysaccharide-Induced Alveolar Epithelial-to-Mesenchymal Transition and Pulmonary Fibrosis.

Science.gov (United States)

Dong, Wen-Wen; Zhang, Yun-Qian; Zhu, Xiao-Yan; Mao, Yan-Fei; Sun, Xue-Jun; Liu, Yu-Jian; Jiang, Lai

2017-05-19

BACKGROUND Fibrotic change is one of the important reasons for the poor prognosis of patients with acute respiratory distress syndrome (ARDS). The present study investigated the effects of hydrogen-rich saline, a selective hydroxyl radical scavenger, on lipopolysaccharide (LPS)-induced pulmonary fibrosis. MATERIAL AND METHODS Male ICR mice were divided randomly into 5 groups: Control, LPS-treated plus vehicle treatment, and LPS-treated plus hydrogen-rich saline (2.5, 5, or 10 ml/kg) treatment. Twenty-eight days later, fibrosis was assessed by determination of collagen deposition, hydroxyproline, and type I collagen levels. Development of epithelial-to-mesenchymal transition (EMT) was identified by examining protein expressions of E-cadherin and α-smooth muscle actin (α-SMA). Transforming growth factor (TGF)-β1 content, total antioxidant capacity (T-AOC), malondialdehyde (MDA) content, catalase (CAT), and superoxide dismutase (SOD) activity were determined. RESULTS Mice exhibited increases in collagen deposition, hydroxyproline, type I collagen contents, and TGF-β1 production in lung tissues after LPS treatment. LPS-induced lung fibrosis was associated with increased expression of α-SMA, as well as decreased expression of E-cadherin. In addition, LPS treatment increased MDA levels but decreased T-AOC, CAT, and SOD activities in lung tissues, indicating that LPS induced pulmonary oxidative stress. Hydrogen-rich saline treatment at doses of 2.5, 5, or 10 ml/kg significantly attenuated LPS-induced pulmonary fibrosis. LPS-induced loss of E-cadherin in lung tissues was largely reversed, whereas the acquisition of α-SMA was dramatically decreased by hydrogen-rich saline treatment. In addition, hydrogen-rich saline treatment significantly attenuated LPS-induced oxidative stress. CONCLUSIONS Hydrogen-rich saline may protect against LPS-induced EMT and pulmonary fibrosis through suppressing oxidative stress.

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

Directory of Open Access Journals (Sweden)

Yousri M.A. Welaya

2012-06-01

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

Hydrogen Generation from Sugars via Aqueous-Phase Reforming

International Nuclear Information System (INIS)

Randy D Cortright

2006-01-01

Virent Energy Systems, Inc. is commercializing the Aqueous Phase Reforming (APR) process that allows the generation of hydrogen-rich gas streams from biomass-derived compounds such as glycerol, sugars, and sugar alcohols. The APR process is a unique method that generates hydrogen from aqueous solutions of these oxygenated compounds in a single step reactor process compared to the three or more reaction steps required for hydrogen generation via conventional processes that utilize non-renewable fossil fuels. The key breakthrough of the APR process is that the reforming of these aqueous solutions is done in the liquid phase. The patented APR process occurs at temperatures (150 C to 270 C) where the water-gas shift reaction is favorable, making it possible to generate hydrogen with low amounts of CO in a single chemical reactor. Furthermore, the APR process occurs at pressures (typically 15 to 50 bar) where the hydrogen-rich effluent can be effectively purified using either membrane technology or pressure swing adsorption technology. The utilization of biomass-based compounds allows the APR process to be a carbon neutral method to generate hydrogen. In the near term, the feed-stock of interest is waste glycerol that is being generated in large quantities as a byproduct in the production of bio-diesel. Virent has developed the APR system for on-demand generation of hydrogen-rich fuel gas from either glycerol or sorbitol (the sugar alcohol formed by hydrogenation of glucose) to fuel a stationary internal combustion engine driven generator (10 kW). Under a USDOE funded project, Virent is currently developing the APR process to generate high yields of hydrogen from corn-derived glucose. This project objective is to achieve the DOE 2010 cost target for distributed production from renewable liquid fuels of 3.60 dollars/gge (gasoline gallon equivalent) delivered. (authors)

First principles study of inert-gas (helium, neon, and argon) interactions with hydrogen in tungsten

Energy Technology Data Exchange (ETDEWEB)

Kong, Xiang-Shan [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P. O. Box 1129, Hefei 230031 (China); Hou, Jie [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P. O. Box 1129, Hefei 230031 (China); University of Science and Technology of China, Hefei 230026 (China); Li, Xiang-Yan [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P. O. Box 1129, Hefei 230031 (China); Wu, Xuebang, E-mail: xbwu@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P. O. Box 1129, Hefei 230031 (China); Liu, C.S., E-mail: csliu@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, P. O. Box 1129, Hefei 230031 (China); Chen, Jun-Ling; Luo, G.-N. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

2017-04-15

We have systematically evaluated binding energies of hydrogen with inert-gas (helium, neon, and argon) defects, including interstitial clusters and vacancy-inert-gas complexes, and their stable configurations using first-principles calculations. Our calculations show that these inert-gas defects have large positive binding energies with hydrogen, 0.4–1.1 eV, 0.7–1.0 eV, and 0.6–0.8 eV for helium, neon, and argon, respectively. This indicates that these inert-gas defects can act as traps for hydrogen in tungsten, and impede or interrupt the diffusion of hydrogen in tungsten, which supports the discussion on the influence of inert-gas on hydrogen retention in recent experimental literature. The interaction between these inert-gas defects and hydrogen can be understood by the attractive interaction due to the distortion of the lattice structure induced by inert-gas defects, the intrinsic repulsive interaction between inert-gas atoms and hydrogen, and the hydrogen-hydrogen repelling in tungsten lattice.

Bar quenching in gas-rich galaxies

Science.gov (United States)

Khoperskov, S.; Haywood, M.; Di Matteo, P.; Lehnert, M. D.; Combes, F.

2018-01-01

Galaxy surveys have suggested that rapid and sustained decrease in the star-formation rate (SFR), "quenching", in massive disk galaxies is frequently related to the presence of a bar. Optical and near-IR observations reveal that nearly 60% of disk galaxies in the local universe are barred, thus it is important to understand the relationship between bars and star formation in disk galaxies. Recent observational results imply that the Milky Way quenched about 9-10 Gyr ago, at the transition between the cessation of the growth of the kinematically hot, old, metal-poor thick disk and the kinematically colder, younger, and more metal-rich thin disk. Although perhaps coincidental, the quenching episode could also be related to the formation of the bar. Indeed the transfer of energy from the large-scale shear induced by the bar to increasing turbulent energy could stabilize the gaseous disk against wide-spread star formation and quench the galaxy. To explore the relation between bar formation and star formation in gas rich galaxies quantitatively, we simulated gas-rich disk isolated galaxies. Our simulations include prescriptions for star formation, stellar feedback, and for regulating the multi-phase interstellar medium. We find that the action of stellar bar efficiently quenches star formation, reducing the star-formation rate by a factor of ten in less than 1 Gyr. Analytical and self-consistent galaxy simulations with bars suggest that the action of the stellar bar increases the gas random motions within the co-rotation radius of the bar. Indeed, we detect an increase in the gas velocity dispersion up to 20-35 km s-1 at the end of the bar formation phase. The star-formation efficiency decreases rapidly, and in all of our models, the bar quenches the star formation in the galaxy. The star-formation efficiency is much lower in simulated barred compared to unbarred galaxies and more rapid bar formation implies more rapid quenching.

Measurement of laminar burning velocities and Markstein lengths of diluted hydrogen-enriched natural gas

Energy Technology Data Exchange (ETDEWEB)

Miao, Haiyan; Jiao, Qi; Huang, Zuohua; Jiang, Deming [State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Eng., Xi' an Jiaotong University (China)

2009-01-15

The laminar flame characteristics of natural gas-hydrogen-air-diluent gas (nitrogen/CO{sub 2}) mixtures were studied in a constant volume combustion bomb at various diluent ratios, hydrogen fractions and equivalence ratios. Both unstretched laminar burning velocity and Markstein length were obtained. The results showed that hydrogen fraction, diluent ratio and equivalence ratio have combined influence on laminar burning velocity and flame instability. The unstretched laminar burning velocity is reduced at a rate that is increased with the increase of the diluent ratio. The reduction effect of CO{sub 2} diluent gas is stronger than that of nitrogen diluent gas. Hydrogen-enriched natural gas with high hydrogen fraction can tolerate more diluent gas than that with low hydrogen fraction. Markstein length can either increase or decrease with the increase of the diluent ratio, depending on the hydrogen fraction of the fuel. (author)

Decoration of carbon nano surfaces with hydrogen and hydrogen rich molecules

International Nuclear Information System (INIS)

Zöttl, S.

2013-01-01

The use of helium nano droplets as a matrix to investigate different atomic and molecular samples is a well established experimental technique. The unique properties of helium allow for different analytical methods and at the same time provide a stable ambient temperature. Cluster growth inside helium nano droplets can be accomplished by repeatedly doping the droplets with sample particles in a controlled environment. The experimental work represented in this thesis was performed using helium nano droplets to create clusters of fullerenes like C 60 and C 70 . The adsorption properties of these fullerene clusters regarding hydrogen and hydrogen rich molecules have been subject to investigation. The observed results suggest that curved carbon nano surfaces offer higher storage densities than planar graphite surfaces. The use of C 60 as a model carbon nano structure provides a well understood molecule for testing and evaluating computational methods to calculate surface properties of various carbon nano materials. The cost effective storage of hydrogen for mobile applications plays a key role in the development of alternatives to fossil fuels. For that reason, the application of carbon nano materials to store hydrogen by adsorption has attracted much scientific attention lately. The insights gained in the presented thesis contribute to the collective efforts and deliver more refined tools to estimate the adsorption properties of future carbon nano materials. In addition to the aforementioned, a time-of-flight mass spectrometer for educational purpose has been designed and constructed in the framework of my PhD thesis. The instrument is successfully used in various lab courses and information on the setup can be found in the Appendix of this work. (author) [de

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

Field test of hydrogen in the natural gas grid

Energy Technology Data Exchange (ETDEWEB)

Iskov, H

2010-08-15

In order to prepare for a future use of hydrogen as a fuel gas it became evident that very little information existed regarding the compatibility between long-term exposure and transportation of hydrogen in natural gas pipelines. A program was therefore set to study the transportation in a small-scale pilot grid at the research centre in Hoersholm, Denmark. The test program included steel pipes from the Danish gas transmission grid and polymer pipes from the Danish and Swedish gas distribution grid. The test of polymer pipes was devised so that samples of all test pipes were cut out of the grid each year and analysis performed on these pipe samples; in this way any form of influence on the integrity of the polyethylene pipe would be detected. The analytical program for polymer was devised in order to detect any influence on the additivation of the polyethylene as this has an influence on oxidative resistance, as well as checking already encountered possible degradation caused by extrusion of the material. Further tools as rheology and melt flow rate were used for detecting any structural changes on the material. On the mechanical property side the tensile strength and modulus were followed as well as the most important property for the pipe line, namely slow crack growth. The results of the polymer pipe tests show no degradations of any kind related to the continuous hydrogen exposure for more than 4 years. This is a strong indication of the compatibility to hydrogen of the tested polymer materials PE 80 and PE 100. The object of the steel pipe test was to see the effect on fatigue life of existing natural gas transmission lines with hydrogen replacing the natural gas. Full-scale dynamic tests were performed using randomly selected cut-out API 5L X70 pipe sections with a diameter of 20 inches and a wall thickness of 7 millimetres from the Danish natural gas transmission system. The pipe sections contained field girth weld made during the installation of the pipe

Field test of hydrogen in the natural gas grid

Energy Technology Data Exchange (ETDEWEB)

Iskov, H.

2010-08-15

In order to prepare for a future use of hydrogen as a fuel gas it became evident that very little information existed regarding the compatibility between long-term exposure and transportation of hydrogen in natural gas pipelines. A program was therefore set to study the transportation in a small-scale pilot grid at the research centre in Hoersholm, Denmark. The test program included steel pipes from the Danish gas transmission grid and polymer pipes from the Danish and Swedish gas distribution grid. The test of polymer pipes was devised so that samples of all test pipes were cut out of the grid each year and analysis performed on these pipe samples; in this way any form of influence on the integrity of the polyethylene pipe would be detected. The analytical program for polymer was devised in order to detect any influence on the additivation of the polyethylene as this has an influence on oxidative resistance, as well as checking already encountered possible degradation caused by extrusion of the material. Further tools as rheology and melt flow rate were used for detecting any structural changes on the material. On the mechanical property side the tensile strength and modulus were followed as well as the most important property for the pipe line, namely slow crack growth. The results of the polymer pipe tests show no degradations of any kind related to the continuous hydrogen exposure for more than 4 years. This is a strong indication of the compatibility to hydrogen of the tested polymer materials PE 80 and PE 100. The object of the steel pipe test was to see the effect on fatigue life of existing natural gas transmission lines with hydrogen replacing the natural gas. Full-scale dynamic tests were performed using randomly selected cut-out API 5L X70 pipe sections with a diameter of 20 inches and a wall thickness of 7 millimetres from the Danish natural gas transmission system. The pipe sections contained field girth weld made during the installation of the pipe

A mathematical framework for modelling and evaluating natural gas pipeline networks under hydrogen injection

Energy Technology Data Exchange (ETDEWEB)

Tabkhi, F.; Azzaro-Pantel, C.; Pibouleau, L.; Domenech, S. [Laboratoire de Genie Chimique, UMR5503 CNRS/INP/UPS, 5 rue Paulin Talabot F-BP1301, 31106 Toulouse Cedex 1 (France)

2008-11-15

This article presents the framework of a mathematical formulation for modelling and evaluating natural gas pipeline networks under hydrogen injection. The model development is based on gas transport through pipelines and compressors which compensate for the pressure drops by implying mainly the mass and energy balances on the basic elements of the network. The model was initially implemented for natural gas transport and the principle of extension for hydrogen-natural gas mixtures is presented. The objective is the treatment of the classical fuel minimizing problem in compressor stations. The optimization procedure has been formulated by means of a nonlinear technique within the General Algebraic Modelling System (GAMS) environment. This work deals with the adaptation of the current transmission networks of natural gas to the transport of hydrogen-natural gas mixtures. More precisely, the quantitative amount of hydrogen that can be added to natural gas can be determined. The studied pipeline network, initially proposed in [1] is revisited here for the case of hydrogen-natural gas mixtures. Typical quantitative results are presented, showing that the addition of hydrogen to natural gas decreases significantly the transmitted power: the maximum fraction of hydrogen that can be added to natural gas is around 6 mass% for this example. (author)

Hydrogen-Rich Water Intake Accelerates Oral Palatal Wound Healing via Activation of the Nrf2/Antioxidant Defense Pathways in a Rat Model

Science.gov (United States)

Orihuela-Campos, Rita Cristina; Fukui, Makoto; Ito, Hiro-O

2016-01-01

The wound healing process attempts to restore the integrity and function of the injured tissue. Additionally, proinflammatory cytokines, growth factors, and oxidative stress play important roles in wound healing. The aim of this study was to determine whether hydrogen-rich water intake induces the activation of the Nrf2/antioxidant defense pathway in rat palatal tissue, thereby reducing systemic oxidative stress and proinflammatory cytokine levels and promoting healing-associated genes. A circular excisional wound was created in the oral palatal region, and the wound healing process was observed. The rats were divided into two experimental groups in which either hydrogen-rich water or distilled water was consumed. In the drinking hydrogen-rich water, the palatal wound healing process was accelerated compared to that in the control group. As molecular hydrogen upregulated the Nrf2 pathway, systemic oxidative stresses were decreased by the activation of antioxidant activity. Furthermore, hydrogen-rich water intake reduced proinflammatory cytokine levels and promoted the expression of healing-associated factors in rat palatal tissue. In conclusion, hydrogen-rich water intake exhibited multiple beneficial effects through activation of the Nrf2/antioxidant defense pathway. The results of this study support the hypothesis that oral administration of hydrogen-rich water benefits the wound healing process by decreasing oxidative stress and inflammatory responses. PMID:26798423

Hydrogen extraction from liquid lithium-lead alloy by gas-liquid contact method

International Nuclear Information System (INIS)

Xie Bo; Weng Kuiping; Hou Jianping; Yang Guangling; Zeng Jun

2013-01-01

Hydrogen extraction experiment from liquid lithium-lead alloy by gas-liquid contact method has been carried out in own liquid lithium-lead bubbler (LLLB). Experimental results show that, He is more suitable than Ar as carrier gas in the filler tower. The higher temperature the tower is, the greater hydrogen content the tower exports. Influence of carrier gas flow rate on the hydrogen content in the export is jagged, no obvious rule. Although the difference between experimental results and literature data, but it is feasible that hydrogen isotopes extraction experiment from liquid lithium-lead by gas-liquid contact method, and the higher extraction efficiency increases with the growth of the residence time of the alloy in tower. (authors)

Hydrogen enriched gas production in a multi-stage downdraft gasification process

International Nuclear Information System (INIS)

Dutta, A.; Jarungthammachote, S.

2009-01-01

To achieve hydrogen enriched and low-tar producer gas, multi-stage air-blown and air-steam gasification were studied in this research. Results showed that the tar content from multi-stage air-blown and air-steam gasification was lower compared to the average value of that from downdraft gasification. It was also seen that an air-steam gasification process could potentially increase the hydrogen concentration in the producer gas in the expense of carbon monoxide; however, the summation of hydrogen and carbon monoxide in the producer gas was increased. (author)

Effect of hydrogen on passivation quality of SiNx/Si-rich SiNx stacked layers deposited by catalytic chemical vapor deposition on c-Si wafers

International Nuclear Information System (INIS)

Thi, Trinh Cham; Koyama, Koichi; Ohdaira, Keisuke; Matsumura, Hideki

2015-01-01

We investigate the role of hydrogen content and fixed charges of catalytic chemical vapor deposited (Cat-CVD) SiN x /Si-rich SiN x stacked layers on the quality of crystalline silicon (c-Si) surface passivation. Calculated density of fixed charges is on the order of 10 12 cm −2 , which is high enough for effective field effect passivation. Hydrogen content in the films is also found to contribute significantly to improvement in passivation quality of the stacked layers. Furthermore, Si-rich SiN x films deposited with H 2 dilution show better passivation quality of SiN x /Si-rich SiN x stacked layers than those prepared without H 2 dilution. Effective minority carrier lifetime (τ eff ) in c-Si passivated by SiN x /Si-rich SiN x stacked layers is as high as 5.1 ms when H 2 is added during Si-rich SiN x deposition, which is much higher than the case of using Si-rich SiN x films prepared without H 2 dilution showing τ eff of 3.3 ms. - Highlights: • Passivation mechanism of Si-rich SiN x /SiN x stacked layers is investigated. • H atoms play important role in passivation quality of the stacked layer. • Addition of H 2 gas during Si-rich SiN x film deposition greatly enhances effective minority carrier lifetime (τ eff ). • For a Si-rich SiN x film with refractive index of 2.92, τ eff improves from 3.3 to 5.1 ms by H 2 addition

Combustion characteristics of natural gas-hydrogen hybrid fuel turbulent diffusion flame

Energy Technology Data Exchange (ETDEWEB)

El-Ghafour, S.A.A.; El-dein, A.H.E.; Aref, A.A.R. [Mechanical Power Engineering Department, Faculty of Engineering, Suez Canal University, Port-Said (Egypt)

2010-03-15

Combustion characteristics of natural gas - hydrogen hybrid fuel were investigated experimentally in a free jet turbulent diffusion flame flowing into a slow co-flowing air stream. Experiments were carried out at a constant jet exit Reynolds number of 4000 and with a wide range of NG-H{sub 2} mixture concentrations, varied from 100%NG to 50%NG-50% H{sub 2} by volume. The effect of hydrogen addition on flame stability, flame length, flame structure, exhaust species concentration and pollutant emissions was conducted. Results showed that, hydrogen addition sustains a progressive improvement in flame stability and reduction in flame length, especially for relatively high hydrogen concentrations. Hydrogen-enriched flames found to have a higher combustion temperatures and reactivity than natural gas flame. Also, it was found that hydrogen addition to natural gas is an ineffective strategy for NO and CO reduction in the studied range, while a significant reduction in the %CO{sub 2} molar concentration by about 30% was achieved. (author)

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

International Nuclear Information System (INIS)

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

2003-01-01

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

Triboelectric Hydrogen Gas Sensor with Pd Functionalized Surface

Directory of Open Access Journals (Sweden)

Sung-Ho Shin

2016-10-01

Full Text Available Palladium (Pd-based hydrogen (H2 gas sensors have been widely investigated thanks to its fast reaction and high sensitivity to hydrogen. Various sensing mechanisms have been adopted for H2 gas sensors; however, all the sensors must be powered through an external battery. We report here an H2 gas sensor that can detect H2 by measuring the output voltages generated during contact electrification between two friction surfaces. When the H2 sensor, composed of Pd-coated ITO (indium tin oxide and PET (polyethylene Terephthalate film, is exposed to H2, its output voltage is varied in proportion to H2 concentration because the work function (WF of Pd-coated surface changes, altering triboelectric charging behavior. Specifically, the output voltage of the sensor is gradually increased as exposing H2 concentration increases. Reproducible and sensitive sensor response was observed up 1% H2 exposure. The approach introduced here can easily be adopted to development of triboelectric gas sensors detecting other gas species.

Recommendations on X80 steel for the design of hydrogen gas transmission pipelines

International Nuclear Information System (INIS)

Briottet, L.; Batisse, R.; De Dinechin, G.; Langlois, P.; Thiers, L.

2012-01-01

By limiting the pipes thickness necessary to sustain high pressure, high-strength steels could prove economically relevant for transmitting large gas quantities in pipelines on long distance. Up to now, the existing hydrogen pipelines have used lower-strength steels to avoid any hydrogen embrittlement. The CATHY-GDF project, funded by the French National Agency for Research, explored the ability of an industrial X80 grade for the transmission of pressurized hydrogen gas in large diameter pipelines. This project has developed experimental facilities to test the material under hydrogen gas pressure. Indeed, tensile, toughness, crack propagation and disc rupture tests have been performed. From these results, the effect of hydrogen pressure on the size of some critical defects has been analyzed allowing proposing some recommendations on the design of X80 pipe for hydrogen transport. Cost of Hydrogen transport could be several times higher than natural gas one for a given energy amount. Moreover, building hydrogen pipeline using high grade steels could induce a 10 to 40% cost benefit instead of using low grade steels, despite their lower hydrogen susceptibility. (authors)

Production of hydrogen from hydrocarbons

Energy Technology Data Exchange (ETDEWEB)

Lohmueller, R

1984-03-01

Hydrocarbons are the preferred starting materials for the industrial production of hydrogen. Most hydrogen is produced by steam reforming of light hydrocarbons. Partial oxidation of heavy oil and residue is used for the production of H/sub 2/ and synthesis gas in large plants. In both cases gas purification was improved. Hydrogen-rich gases like coke oven gas, refinery-offgas, and offgases from the chemical and petrochemical industry have high potential for becoming a major source of hydrogen. Processes for recovering H/sub 2/ (and by-products) are condensation and rectification at low temperatures and, most attractive and versatile for the production of very pure H/sub 2/, adsorption (PSA). The environmental impact of H/sub 2/ production lies mainly in the emission of CO/sub 2/ and heat. Other forms of pollution can be considerably reduced by conventional methods. The economy of H/sub 2/ production depends essentially on price and availability of the raw materials.

A comparative economic assessment of hydrogen production from coke oven gas, water electrolysis and steam reforming of natural gas

International Nuclear Information System (INIS)

Nguyen, Y.V.; Ngo, Y.A.; Tinkler, M.J.; Cowan, N.

2003-01-01

This paper presents the comparative economics of producing hydrogen for the hydrogen economy by recovering it from waste gases from the steel industry, by water electrolysis and by conventional steam reforming of natural gas. Steel makers produce coke for their blast furnace operation by baking coal at high temperature in a reduced environment in their coke ovens. These ovens produce a coke oven gas from the volatiles in the coal. The gas, containing up to 60% hydrogen, is commonly used for its heating value with some of it being flared. The feasibility of recovering this hydrogen from the gas will be presented. A comparison of this opportunity with that of hydrogen from water electrolysis using low cost off-peak electricity from nuclear energy will be made. The impact of higher daily average electricity rate in Ontario will be discussed. The benefits of these opportunities compared with those from conventional steam reforming of natural gas will be highlighted. (author)

Hydrodesulphurization of Light Gas Oil using hydrogen from the Water Gas Shift Reaction

Science.gov (United States)

Alghamdi, Abdulaziz

2009-12-01

The production of clean fuel faces the challenges of high production cost and complying with stricter environmental regulations. In this research, the ability of using a novel technology of upgrading heavy oil to treat Light Gas Oil (LGO) will be investigated. The target of this project is to produce cleaner transportation fuel with much lower cost of production. Recently, a novel process for upgrading of heavy oil has been developed at University of Waterloo. It is combining the two essential processes in bitumen upgrading; emulsion breaking and hydroprocessing into one process. The water in the emulsion is used to generate in situ hydrogen from the Water Gas Shift Reaction (WGSR). This hydrogen can be used for the hydrogenation and hydrotreating reaction which includes sulfur removal instead of the expensive molecular hydrogen. This process can be carried out for the upgrading of the bitumen emulsion which would improve its quality. In this study, the hydrodesulphurization (HDS) of LGO was conducted using in situ hydrogen produced via the Water Gas Shift Reaction (WGSR). The main objective of this experimental study is to evaluate the possibility of producing clean LGO over dispersed molybdenum sulphide catalyst and to evaluate the effect of different promoters and syn-gas on the activity of the dispersed Mo catalyst. Experiments were carried out in a 300 ml Autoclave batch reactor under 600 psi (initially) at 391°C for 1 to 3 hours and different amounts of water. After the hydrotreating reaction, the gas samples were collected and the conversion of carbon monoxide to hydrogen via WGSR was determined using a refinery gas analyzer. The sulphur content in liquid sample was analyzed via X-Ray Fluorescence. Experimental results showed that using more water will enhance WGSR but at the same time inhibits the HDS reaction. It was also shown that the amount of sulfur removed depends on the reaction time. The plan is to investigate the effect of synthesis gas (syngas

Effects of hydrogen mixture into helium gas on deuterium removal from lithium titanate

Energy Technology Data Exchange (ETDEWEB)

Tsuchiya, Akihito, E-mail: tsuchiya@frontier.hokudai.ac.jp [Laboratory of Plasma Physics and Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo 060-8628 (Japan); Hino, Tomoaki; Yamauchi, Yuji; Nobuta, Yuji [Laboratory of Plasma Physics and Engineering, Hokkaido University, Kita-13, Nishi-8, Kita-ku, Sapporo 060-8628 (Japan); Akiba, Masato; Enoeda, Mikio [Japan Atomic Energy Agency, 801-1, Mukoyama, Naka 311-0193 (Japan)

2013-10-15

Lithium titanate (Li{sub 2}TiO{sub 3}) pebbles were irradiated with deuterium ions with energy of 1.7 keV and then exposed to helium or helium–hydrogen mixed gas at various temperatures, in order to evaluate the effects of gas exposure on deuterium removal from the pebbles. The amounts of residual deuterium in the pebbles were measured by thermal desorption spectroscopy. The mixing of hydrogen gas into helium gas enhanced the removal amount of deuterium. In other words, the amount of residual deuterium after the helium–hydrogen mixed gas exposure at lower temperature was lower than that after the helium gas exposure. In addition, we also evaluated the pebbles exposed to the helium gas with different hydrogen mixture ratio from 0% to 1%, at 573 K. Although the amount of residual deuterium in the pebbles after the exposure decreased with increasing the hydrogen mixture ratio, the implanted deuterium partly remained after the exposure. These results suggest that the tritium inventory may occur at low temperature region in the blanket during the operation.

China organic-rich shale geologic features and special shale gas production issues

Directory of Open Access Journals (Sweden)

Yiwen Ju

2014-06-01

Full Text Available The depositional environment of organic-rich shale and the related tectonic evolution in China are rather different from those in North America. In China, organic-rich shale is not only deposited in marine environment, but also in non-marine environment: marine-continental transitional environment and lacustrine environment. Through analyzing large amount of outcrops and well cores, the geologic features of organic-rich shale, including mineral composition, organic matter richness and type, and lithology stratigraphy, were analyzed, indicating very special characteristics. Meanwhile, the more complex and active tectonic movements in China lead to strong deformation and erosion of organic-rich shale, well-development of fractures and faults, and higher thermal maturity and serious heterogeneity. Co-existence of shale gas, tight sand gas, and coal bed methane (CBM proposes a new topic: whether it is possible to co-produce these gases to reduce cost. Based on the geologic features, the primary production issues of shale gas in China were discussed with suggestions.

PALLADIUM DOPED TIN OXIDE BASED HYDROGEN GAS SENSORS FOR SAFETY APPLICATIONS

International Nuclear Information System (INIS)

Kasthurirengan, S.; Behera, Upendra; Nadig, D. S.

2010-01-01

Hydrogen is considered to be a hazardous gas since it forms a flammable mixture between 4 to 75% by volume in air. Hence, the safety aspects of handling hydrogen are quite important. For this, ideally, highly selective, fast response, small size, hydrogen sensors are needed. Although sensors based on different technologies may be used, thin-film sensors based on palladium (Pd) are preferred due to their compactness and fast response. They detect hydrogen by monitoring the changes to the electrical, mechanical or optical properties of the films. We report the development of Pd-doped tin-oxide based gas sensors prepared on thin ceramic substrates with screen printed platinum (Pt) contacts and integrated nicrome wire heaters. The sensors are tested for their performances using hydrogen-nitrogen gas mixtures to a maximum of 4%H 2 in N 2 . The sensors detect hydrogen and their response times are less than a few seconds. Also, the sensor performance is not altered by the presence of helium in the test gas mixtures. By the above desired performance characteristics, field trials of these sensors have been undertaken. The paper presents the details of the sensor fabrication, electronic circuits, experimental setup for evaluation and the test results.

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

Energy Technology Data Exchange (ETDEWEB)

NONE

1976-03-31

This research aims at establishment of the meaning of using hydrogen as gas turbine fuel in the hydrogen energy system and various conditions for hydrogen gas turbines, and approaches to the feasibility study and R and D of hydrogen gas turbines in the future. In fiscal 1975, researches were made on (1) feasibility study on hydrogen-oxygen gas turbine, (2) establishment of various conditions for technical, social and economic realization of hydrogen gas turbines in the total energy system, and (3) study on technical troubles to be solved for realization of hydrogen gas turbines. For the above researches, study was made on hydrogen combustion based on the hydrogen combustion test result of gas mixture including hydrogen, and on the feasibility of aphodid cycle. In addition, study on the applicability of hydrogen-oxygen gas turbines, comparative study on hydrogen-oxygen gas turbine, MHD power generation and fuel cell, and the future prospect of hydrogen gas turbines for ships were made to place this hydrogen gas turbine. (NEDO)

Rapid hydrogen gas generation using reactive thermal decomposition of uranium hydride.

Energy Technology Data Exchange (ETDEWEB)

Kanouff, Michael P.; Van Blarigan, Peter; Robinson, David B.; Shugard, Andrew D.; Gharagozloo, Patricia E.; Buffleben, George M.; James, Scott Carlton; Mills, Bernice E.

2011-09-01

Oxygen gas injection has been studied as one method for rapidly generating hydrogen gas from a uranium hydride storage system. Small scale reactors, 2.9 g UH{sub 3}, were used to study the process experimentally. Complimentary numerical simulations were used to better characterize and understand the strongly coupled chemical and thermal transport processes controlling hydrogen gas liberation. The results indicate that UH{sub 3} and O{sub 2} are sufficiently reactive to enable a well designed system to release gram quantities of hydrogen in {approx} 2 seconds over a broad temperature range. The major system-design challenge appears to be heat management. In addition to the oxidation tests, H/D isotope exchange experiments were performed. The rate limiting step in the overall gas-to-particle exchange process was found to be hydrogen diffusion in the {approx}0.5 {mu}m hydride particles. The experiments generated a set of high quality experimental data; from which effective intra-particle diffusion coefficients can be inferred.

Alleviation of cadmium toxicity in Medicago sativa by hydrogen-rich water

Energy Technology Data Exchange (ETDEWEB)

Cui, Weiti; Gao, Cunyi; Fang, Peng [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Lin, Guoqing [Laboratory Center of Life Sciences, Co. Laboratory of Nanjing Agricultural University and Carl Zeiss Far East, Nanjing Agricultural University, Nanjing 210095 (China); Shen, Wenbiao, E-mail: wbshenh@njau.edu.cn [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China)

2013-09-15

Highlights: • HRW can alleviate Cd-induced alfalfa seedling growth inhibition and DNA laddering. • HRW alleviates Cd-induced oxidative stress by activating antioxidant enzymes. • Cd uptake in alfalfa seedling roots was decreased by HRW. • HRW can re-establish glutathione homeostasis under Cd stress. -- Abstract: Hydrogen gas (H{sub 2}) induces plant tolerance to several abiotic stresses, including salinity and paraquat exposure. However, the role of H{sub 2} in cadmium (Cd)-induced stress amelioration is largely unknown. Here, pretreatment with hydrogen-rich water (HRW) was used to characterize physiological roles and molecular mechanisms of H{sub 2} in the alleviation of Cd toxicity in alfalfa plants. Our results showed that the addition of HRW at 10% saturation significantly decreased contents of thiobarbituric acid reactive substances (TBARS) caused by Cd, and inhibited the appearance of Cd toxicity symptoms, including the improvement of root elongation and seedling growth. These responses were related to a significant increase in the total or isozymatic activities of representative antioxidant enzymes, or their corresponding transcripts. In vivo imaging of reactive oxygen species (ROS), and the detection of lipid peroxidation and the loss of plasma membrane integrity provided further evidence for the ability of HRW to improve Cd tolerance significantly, which was consistent with a significant enhancement of the ratio of reduced/oxidized (homo)glutathione ((h)GSH). Additionally, plants pretreated with HRW accumulated less amounts of Cd. Together, this study suggested that the usage of HRW could be an effective approach for Cd detoxification and could be explored in agricultural production systems.

Alleviation of cadmium toxicity in Medicago sativa by hydrogen-rich water

International Nuclear Information System (INIS)

Cui, Weiti; Gao, Cunyi; Fang, Peng; Lin, Guoqing; Shen, Wenbiao

2013-01-01

Highlights: • HRW can alleviate Cd-induced alfalfa seedling growth inhibition and DNA laddering. • HRW alleviates Cd-induced oxidative stress by activating antioxidant enzymes. • Cd uptake in alfalfa seedling roots was decreased by HRW. • HRW can re-establish glutathione homeostasis under Cd stress. -- Abstract: Hydrogen gas (H 2 ) induces plant tolerance to several abiotic stresses, including salinity and paraquat exposure. However, the role of H 2 in cadmium (Cd)-induced stress amelioration is largely unknown. Here, pretreatment with hydrogen-rich water (HRW) was used to characterize physiological roles and molecular mechanisms of H 2 in the alleviation of Cd toxicity in alfalfa plants. Our results showed that the addition of HRW at 10% saturation significantly decreased contents of thiobarbituric acid reactive substances (TBARS) caused by Cd, and inhibited the appearance of Cd toxicity symptoms, including the improvement of root elongation and seedling growth. These responses were related to a significant increase in the total or isozymatic activities of representative antioxidant enzymes, or their corresponding transcripts. In vivo imaging of reactive oxygen species (ROS), and the detection of lipid peroxidation and the loss of plasma membrane integrity provided further evidence for the ability of HRW to improve Cd tolerance significantly, which was consistent with a significant enhancement of the ratio of reduced/oxidized (homo)glutathione ((h)GSH). Additionally, plants pretreated with HRW accumulated less amounts of Cd. Together, this study suggested that the usage of HRW could be an effective approach for Cd detoxification and could be explored in agricultural production systems

Device for removing hydrogen gas from the safety containment vessel of a nuclear reactor

International Nuclear Information System (INIS)

Stiefel, M.

1983-01-01

The safe processing of all concentrations of gas mixtures should be possible with such a device using a thermal recombiner of compact construction. A recombiner consisting of a metal case and diverter sheets situated in it is heated by induction. The incoming pipe for the gas mixture enriched with hydrogen and the outgoing pipe for the gas mixture with low hydrogen content are connected together by a three way valve. The third connection to the safety valve takes the larger port of the gas mixture with low hydrogen content back to the safety containment vessel. Sufficient amount of the gas mixture with low hydrogen content is taken via the three way valve to the safety containment vessel to ensure that the hydrogen content of the gas mixture taken to the recombiner remains below the 4% by volume limit. (orig./PW)

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)

Improved Hydrogen Gas Getters for TRU Waste -- Final Report

International Nuclear Information System (INIS)

Mark Stone; Michael Benson; Christopher Orme; Thomas Luther; Eric Peterson

2005-01-01

Alpha radiolysis of hydrogenous waste and packaging materials generates hydrogen gas in radioactive storage containers. For that reason, the Nuclear Regulatory Commission limits the flammable gas (hydrogen) concentration in the Transuranic Package Transporter-II (TRUPACT-II) containers to 5 vol% of hydrogen in air, which is the lower explosion limit. Consequently, a method is needed to prevent the build up of hydrogen to 5 vol% during the storage and transport of the TRUPACT-II containers (up to 60 days). One promising option is the use of hydrogen getters. These materials scavenge hydrogen from the gas phase and irreversibly bind it in the solid phase. One proven getter is a material called 1,4-bis (phenylethynyl) benzene, or DEB, characterized by the presence of carbon-carbon triple bonds. Carbon may, in the presence of suitable precious metal catalysts such as palladium, irreversibly react with and bind hydrogen. In the presence of oxygen, the precious metal may also eliminate hydrogen by catalyzing the formation of water. This reaction is called catalytic recombination. DEB has the needed binding rate and capacity for hydrogen that potentially could be generated in the TRUPACT II. Phases 1 and 2 of this project showed that uncoated DEB performed satisfactorily in lab scale tests. Based upon these results, Phase 3, the final project phase, included larger scale testing. Test vessels were scaled to replicate the ratio between void space in the inner containment vessel of a TRUPACT-II container and a payload of seven 55-gallon drums. The tests were run with an atmosphere of air for 63.9 days at ambient temperature (15-27 C) and a scaled hydrogen generation rate of 2.60E-07 moles per second (0.35 cc/min). A second type of getter known as VEI, a proprietary polymer hydrogen getter characterized by carbon-carbon double bonds, was also tested in Phase 3. Hydrogen was successfully ''gettered'' by both getter systems. Hydrogen concentrations remained below 5 vol% (in

Improved Hydrogen Gas Getters for TRU Waste -- Final Report

Energy Technology Data Exchange (ETDEWEB)

Mark Stone; Michael Benson; Christopher Orme; Thomas Luther; Eric Peterson

2005-09-01

Alpha radiolysis of hydrogenous waste and packaging materials generates hydrogen gas in radioactive storage containers. For that reason, the Nuclear Regulatory Commission limits the flammable gas (hydrogen) concentration in the Transuranic Package Transporter-II (TRUPACT-II) containers to 5 vol% of hydrogen in air, which is the lower explosion limit. Consequently, a method is needed to prevent the build up of hydrogen to 5 vol% during the storage and transport of the TRUPACT-II containers (up to 60 days). One promising option is the use of hydrogen getters. These materials scavenge hydrogen from the gas phase and irreversibly bind it in the solid phase. One proven getter is a material called 1,4-bis (phenylethynyl) benzene, or DEB, characterized by the presence of carbon-carbon triple bonds. Carbon may, in the presence of suitable precious metal catalysts such as palladium, irreversibly react with and bind hydrogen. In the presence of oxygen, the precious metal may also eliminate hydrogen by catalyzing the formation of water. This reaction is called catalytic recombination. DEB has the needed binding rate and capacity for hydrogen that potentially could be generated in the TRUPACT II. Phases 1 and 2 of this project showed that uncoated DEB performed satisfactorily in lab scale tests. Based upon these results, Phase 3, the final project phase, included larger scale testing. Test vessels were scaled to replicate the ratio between void space in the inner containment vessel of a TRUPACT-II container and a payload of seven 55-gallon drums. The tests were run with an atmosphere of air for 63.9 days at ambient temperature (15-27°C) and a scaled hydrogen generation rate of 2.60E-07 moles per second (0.35 cc/min). A second type of getter known as VEI, a proprietary polymer hydrogen getter characterized by carbon-carbon double bonds, was also tested in Phase 3. Hydrogen was successfully “gettered” by both getter systems. Hydrogen concentrations remained below 5 vol% (in

Construction and performance testing of a secondary cooling system with hydrogen gas (I)

International Nuclear Information System (INIS)

Hishida, M.; Nekoya, S.; Takizuka, T.; Emori, K.; Ogawa, M.; Ouchi, M.; Okamoto, Y.; Sanokawa, K.; Nakano, T.; Hagiwara, T.

1979-08-01

An experimental multi-purpose High-Temperature Gas Cooled Reactor (VHTR) which is supposed to be used for a direct steel-making is now being developed in JAeRI. In order to simulate the heat exchanging system between the primary helium gas and the secondary reducing gas system of VHTR, a hydrogen gas loop was constructed as a secondary cooling system of the helium gas loop. The maximum temperature and the maximum pressure of the hydrogen gas are 900 degrees C and 42 kg/cm 2 x G respectively. The construction of the hydrogen gas loop was completed in January, 1977, and was successfully operated for 1.000 h. Various performance tests, such as the hydrogen permeation test of a He/H2 heat exchanger and the thermal performance test of heat exchangers, were made. Especially, it was proved that hydrogen permeation rate through the heat exchanger was reduced to 1/30 to approximately 1/50 by a method of calorized coating, and the coating was stable during 1.000 h's operation. It was also stable against the temperature changes. This report describes the outline of the facility and performance of the components. (orig.) [de

Producing hydrogen from coke-oven gas: the Solmer project. [PSA process

Energy Technology Data Exchange (ETDEWEB)

Bernard, G; Vidal, J

1984-05-01

After presenting the energy situation at the Solmer plant, where coke-oven gas is produced to excess, the authors examine the technical and economic possibilities of utilizing this gas for hydrogen extraction. They describe a project (based on the PSA process) for producing some 65 t/d of hydrogen and present the technical features of the scheme. An evaluation of the energy and financial costs of producing the hydrogen confirms the competitive status of the process.

Transport of a relativistic electron beam through hydrogen gas

International Nuclear Information System (INIS)

Haan, P. de.

1981-01-01

In this thesis the author describes the transport properties of an electron beam through vacuum and through hydrogen gas with pressure ranging from 25 to 1000 Pa. Maximum beam energy and current are 0.8 MeV and 6 kA, respectively. The pulse length is around 150 ns. A description is given of the experimental device. Also the diagnostics for probing the beam and the plasma, produced by the beam, are discussed, as well as the data acquisition system. The interaction between the beam and hydrogen gas with a pressure around 200 Pa is considered. A plasma with density around 10 19 m -3 is produced within a few nanoseconds. Measurements yield the atomic hydrogen temperature, electron density, beam energy loss, and induced plasma current and these are compared with the results of a model combining gas ionization and dissociation, and turbulent plasma heating. The angular distribution of the beam electrons about the magnetic field axis is discussed. (Auth.)

Hydrogen Gas Production in a Stand-Alone Wind Farm

Directory of Open Access Journals (Sweden)

M. Naziry Kordkandy

2017-04-01

Full Text Available This paper is analyzing the operation of a stand-alone wind farm with variable speed turbines, permanent magnet synchronous generators (PMSG and a system for converting wind energy during wind speed variations. On this paper, the design and modeling of a wind system which uses PMSG’s to provide the required power of a hydrogen gas electrolyzer system, is discussed. This wind farm consists of three wind turbines, boost DC-DC converters, diode full bridge rectifiers, permanent magnet synchronous generators, MPPT control and a hydrogen gas electrolyzer system. The MPPT controller based on fuzzy logic is designed to adjust the duty ratio of the boost DC-DC converters to absorb maximum power. The proposed fuzzy logic controller assimilates, with (PSF MPPT algorithm which generally used to absorb maximum power from paralleled wind turbines and stores it in form of hydrogen gas. The system is modeled and its behavior is studied using the MATLAB software.

Prediction of Non-Equilibrium Kinetics of Fuel-Rich Kerosene/LOX Combustion in Gas Generator

International Nuclear Information System (INIS)

Yu, Jung Min; Lee, Chang Jin

2007-01-01

Gas generator is the device to produce high enthalpy gases needed to drive turbo-pump system in liquid rocket engine. And, the combustion temperature in gas generator should be controlled below around 1,000K to avoid any possible thermal damages to turbine blade by using either fuel rich combustion or oxidizer rich combustion. Thus, nonequilibrium chemical reaction dominates in fuel-rich combustion of gas generator. Meanwhile, kerosene is a compounded fuel with various types of hydrocarbon elements and difficult to model the chemical kinetics. This study focuses on the prediction of the non-equilibrium reaction of fuel rich kerosene/LOX combustion with detailed kinetics developed by Dagaut using PSR (Perfectly Stirred Reactor) assumption. In Dagaut's surrogate model for kerosene, chemical kinetics of kerosene consists of 1,592 reaction steps with 207 chemical species. Also, droplet evaporation time is taken into account in the PSR calculation by changing the residence time of droplet in the gas generator. Frenklach's soot model was implemented along with detailed kinetics to calculate the gas properties of fuel rich combustion efflux. The results could provide very reliable and accurate numbers in the prediction of combustion gas temperature,species fraction and material properties

RECOILING MASSIVE BLACK HOLES IN GAS-RICH GALAXY MERGERS

International Nuclear Information System (INIS)

Guedes, Javiera; Madau, Piero; Mayer, Lucio; Callegari, Simone

2011-01-01

The asymmetric emission of gravitational waves produced during the coalescence of a massive black hole (MBH) binary imparts a velocity 'kick' to the system that can displace the hole from the center of its host. Here, we study the trajectories and observability of MBHs recoiling in three (one major, two minor) gas-rich galaxy merger remnants that were previously simulated at high resolution, and in which the pairing of the MBHs had been shown to be successful. We run new simulations of MBHs recoiling in the major merger remnant with Mach numbers in the range 1≤M≤6 and use simulation data to construct a semi-analytical model for the orbital evolution of MBHs in gas-rich systems. We show the following. (1) In major merger remnants the energy deposited by the moving hole into the rotationally supported, turbulent medium makes a negligible contribution to the thermodynamics of the gas. This contribution becomes significant in minor merger remnants, potentially allowing for an electromagnetic signature of MBH recoil. (2) In major merger remnants, the combination of both deeper central potential well and drag from high-density gas confines even MBHs with kick velocities as high as 1200 km s -1 within 1 kpc from the host's center. (3) Kinematically offset nuclei may be observable for timescales of a few Myr in major merger remnants in the case of recoil velocities in the range 700-1000 km s -1 . (4) In minor merger remnants the effect of gas drag is weaker, and MBHs with recoil speeds in the range 300-600 km s -1 will wander through the host halo for longer timescales. When accounting for the probability distribution of kick velocities, however, we find that the likelihood of observing recoiling MBHs in gas-rich galaxy mergers is very low even in the best-case scenario.

Achievement report for fiscal 1982 on Sunshine Program. Research and development of coal gasification (Feasibility study of fluidized gasification process by pressurized hydrogenation); 1982 nendo sekitan gas ka no kenkyu kaihatsu seika hokokusho. Kaatsu suiten ryudo gas ka process no feasibility study

Energy Technology Data Exchange (ETDEWEB)

NONE

1983-01-01

This report covers the results of a feasibility study conducted for the 'Research and development of high-calorie gas production technology (Fluidized gasification process by pressurized hydrogenation)' entrusted to the Mifuji Ironworks during the period 1974-1977 and then entrusted to the Babcock-Hitachi K.K. in the period 1978-present. The hydrogenation gasification process is characterized in that hydrogen serves as the gasification agent for the generation of a methane-rich high-calorie gas. It is preferred that the gasification temperature be relatively low and the pressure high for a hydrogenation gasification reaction. Under the Sunshine Program, development efforts are under way to produce a high-calorie gas, clean and its combustion easy to control, under a pressure of 30kg/cm{sup 2}G, more or less. In this pressurized gasification process, it is important to acquire high-concentration hydrogen for hydrogenation gasification simultaneously with the hydrogenation gasification reaction. In order to achieve the goal, a study is made of a new separated reaction type wet gasification furnace capable of generating high-concentration hydrogen efficiently and economically, and research is under way for the development of such a furnace. The results of element studies and of this feasibility study, and future tasks are compiled into this report. (NEDO)

Power to gas. The final breakthrough for the hydrogen economy?

Energy Technology Data Exchange (ETDEWEB)

Winkler-Goldstein, Raphael [Germany Trade and Invest (GTAI), Paris (France); Rastetter, Aline [Alphea Hydrogene, Forbach (France)

2013-04-01

In Germany more than 20% of the energy mix is made up of renewable energy and its share is rapidly increasing. The federal government expects renewables to account for 35% of Germany's electricity consumption by 2020, 50% by 2030 and 80% by 2050. According to the German Energy Agency, multi-billion euro investments in energy storage are expected by 2020 in order to reach these goals. The growth of this fluctuating energy supply has created demand for innovative storage options in Germany and it is accelerating the development of technologies in this field. Along with batteries and smart grids, hydrogen is expected to be one of the lead technologies. 2010 a commercialization roadmap for wind hydrogen was set up by the two northern federal states of Hamburg and Schleswig-Holstein with the goal of utilizing surplus wind power for the electrolytic production of hydrogen. With the creation of the 'performing energy initiative', 2011, Brandenburg and Lower Saxony joined this undertaking. The aim of this initiative is to set up demonstration projects in order to develop and optimize wind-hydrogen hybrid systems and prepare their commercialization for the time after 2020. Beside the conversion of hydrogen into electricity and fuel for cars, further markets like raw material for the chemical, petrochemical, metallurgy and food industry are going to be addressed. Considering the fact there are over 40 caves currently used for natural gas storage with a total volume of 23.5 billion cubic meters and 400 000 km gas grid available in Germany, the German Technical and Scientific Association for Gas and Water sees opportunities for hydrogen to be fed into the existing natural gas grid network. The name of this concept is power-to-gas. According to the current DVGW-Standards natural gas in Germany can contain up to 5% hydrogen. The GERG, European Group on the Gas Research sees potential to increase this amount up to 6% to 20%. Power-to-gas could serve both for fuel and for the

Scaled Testing of Hydrogen Gas Getters for Transuranic Waste

International Nuclear Information System (INIS)

Kaszuba, J.; Mroz, E.; Haga, M.; Hollis, W. K.; Peterson, E.; Stone, M.; Orme, C.; Luther, T.; Benson, M.

2006-01-01

Alpha radiolysis of hydrogenous waste and packaging materials generates hydrogen gas in radioactive storage and shipment containers. Hydrogen forms a flammable mixture with air over a wide range of concentrations (5% to 75%), and very low energy is needed to ignite hydrogen-air mixtures. For these reasons, the concentration of hydrogen in waste shipment containers (Transuranic Package Transporter-II or TRUPACT-II containers) needs to remain below the lower explosion limit of hydrogen in air (5 vol%). Accident scenarios and the resulting safety analysis require that this limit not be exceeded. The use of 'hydrogen getters' is being investigated as a way to prevent the build up of hydrogen in TRUPACT-II containers. Preferred getters are solid materials that scavenge hydrogen from the gas phase and chemically and irreversibly bind it into the solid state. In this study, two getter systems are evaluated: a) 1,4-bis (phenylethynyl)benzene or DEB, characterized by the presence of carbon-carbon triple bonds; and b) a proprietary polymer hydrogen getter, VEI or TruGetter, characterized by carbon-carbon double bonds. Carbon in both getter types may, in the presence of suitable precious metal catalysts such as palladium, irreversibly react with and bind hydrogen. With oxygen present, the precious metal may also eliminate hydrogen by catalyzing the formation of water. This reaction is called catalytic recombination. DEB and VEI performed satisfactorily in lab scale tests using small test volumes (ml-scale), high hydrogen generation rates, and short time spans of hours to days. The purpose of this study is to evaluate whether DEB and VEI perform satisfactorily in actual drum-scale tests with realistic hydrogen generation rates and time frames. The two getter systems were evaluated in test vessels comprised of a Gas Generation Test Program-style bell-jar and a drum equipped with a composite drum filter. The vessels were scaled to replicate the ratio between void space in the

Metal/glass composites for analysis of hydrogen isotopes by gas-chromatography

International Nuclear Information System (INIS)

Nicolae, Constantin Adrian; Sisu, Claudia; Stefanescu, Doina; Stanciu, Vasile

1999-01-01

The separation process of hydrogen isotopes by cryogenic distillation or thermal diffusion is a key technology for tritium separation from heavy water in CANDU reactor and for tritium fuel cycle in thermonuclear fusion reactor. In each process, analytical techniques for analyzing the hydrogen isotope mixture are required. An extensive experimental research has been carried out in order to produce the most suitable adsorbents and to establish the best operating conditions for selective separation and analysis of hydrogen isotopes by gas-chromatography. This paper describes the preparation of adsorbent materials used as stationary phases in the gas-chromatographic column for hydrogen isotope separation and the treatment (activation) of stationary phases. Modified thermoresisting glass with Fe(NH 4 ) 2 (SO 4 ) 2 ·6H 2 O and Cr 2 O 3 respectively have been experimentally investigated at 77 K for H 2 , HD and D 2 separation and the results of chromatographic runs are reported and discussed. The gas-chromatographic apparatus used in this study is composed of a Hewlett-Packard 7620A gas-chromatograph equipped with a gas carrier flow rate controller and a thermal conductivity detector. The apparatus comprises also a Dewar vessel containing the separation column. The hydrogen isotopes, H 2 , HD, D 2 , and their mixture have been obtained in our laboratories. The best operating conditions and parameters of the Fe 3+ /glass adsorbent column , i.e. granulometry, column length, pressure-drop along the column, carrier gas flow rate and sample volume have been studied by means of the analysis of the retention times, separation factors and HETP. (authors)

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.

Gas-rich dwarfs and accretion phenomena in early-type galaxies

International Nuclear Information System (INIS)

Silk, J.; Norman, C.

1979-01-01

Recent constraints on intergalactic H I clouds suggest that allowable accretion rates by several luminous early-type galaxies are too low to account for their observed H I content. We have therefore developed an alternative model, wherein gas-rich dwarf galaxies are accreted into galactic halos. This process is significant in groups of galaxies only when a sufficiently high density of gas-rich dwarfs (approx.30 Mpc -3 ) is present. The dwarf galaxy gas content plays a crucial role in enabling the galaxy to be trapped in the halo by interaction with a galactic wind or extensive gaseous corona. Gas stripping occurs, resulting in the formation of dwarf spheroidal systems that populate the outer halos of massive galaxies and in the injection of a system of clouds into the halo. If the clouds are initially confined by the pressure of the ambient halo medium, dissipation and continuing infall enable the clouds to accrete into the central regions of galaxies before becoming gravitationally unstable and presumably forming stars. Consequences of this scenario include the production of a radial abundance gradient and infall of adequate amounts of neutral gas to account for the observations of H I in early-type galaxies. This gas accretion rate is also sufficient to feed active nuclei and radio sources. An important cosmological implication of our model is that, because the characteristic time scale of a gas-rich dwarf galaxy to be accreted and lose its gas is comparable to a Hubble time, there many have been a far more extensive primordial distribution of such systems at earlier epochs. This implies that accretion rates were greatly enhanced at relatively recent epochs (z> or approx. =0.5) and could account both for the rapid cosmological evolution inferred for radio galaxies and quasars, and for the observed frequency of occurrence of quasar absorption-line systems

Benchmarking DFT and TD-DFT Functionals for the Ground and Excited States of Hydrogen-Rich Peptide Radicals.

Science.gov (United States)

Riffet, Vanessa; Jacquemin, Denis; Cauët, Emilie; Frison, Gilles

2014-08-12

We assess the pros and cons of a large panel of DFT exchange-correlation functionals for the prediction of the electronic structure of hydrogen-rich peptide radicals formed after electron attachment on a protonated peptide. Indeed, despite its importance in the understanding of the chemical changes associated with the reduction step, the question of the attachment site of an electron and, more generally, of the reduced species formed in the gas phase through electron-induced dissociation (ExD) processes in mass spectrometry is still a matter of debate. For hydrogen-rich peptide radicals in which several positive groups and low-lying π* orbitals can capture the incoming electron in ExD, inclusion of full Hartree-Fock exchange at long-range interelectronic distance is a prerequisite for an accurate description of the electronic states, thereby excluding several popular exchange-correlation functionals, e.g., B3LYP, M06-2X, or CAM-B3LYP. However, we show that this condition is not sufficient by comparing the results obtained with asymptotically correct range-separated hybrids (M11, LC-BLYP, LC-BPW91, ωB97, ωB97X, and ωB97X-D) and with reference CASSCF-MRCI and EOM-CCSD calculations. The attenuation parameter ω significantly tunes the spin density distribution and the excited states vertical energies. The investigated model structures, ranging from methylammonium to hexapeptide, allow us to obtain a description of the nature and energy of the electronic states, depending on (i) the presence of hydrogen bond(s) around the cationic site(s), (ii) the presence of π* molecular orbitals (MOs), and (iii) the selected DFT approach. It turns out that, in the present framework, LC-BLYP and ωB97 yields the most accurate results.

Preparation and Hydrogen Storage Properties of Mg-Rich Mg-Ni Ultrafine Particles

Directory of Open Access Journals (Sweden)

Jianxin Zou

2012-01-01

Full Text Available In the present work, Mg-rich Mg-Ni ultrafine powders were prepared through an arc plasma method. The phase components, microstructure, and hydrogen storage properties of the powders were carefully investigated. It is found that Mg2Ni and MgNi2 could be obtained directly from the vapor state reactions between Mg and Ni, depending on the local vapor content in the reaction chamber. A nanostructured MgH2 + Mg2NiH4 hydrogen storage composite could be generated after hydrogenation of the Mg-Ni ultrafine powders. After dehydrogenation, MgH2 and Mg2NiH4 decomposed into nanograined Mg and Mg2Ni, respectively. Thermogravimetry/differential scanning calorimetry (TG/DSC analyses showed that Mg2NiH4 phase may play a catalytic role in the dehydriding process of the hydrogenated Mg ultrafine particles.

Hysec Process: production of high-purity hydrogen from coke oven gas

Energy Technology Data Exchange (ETDEWEB)

Nishida, S

1984-01-01

An account is given of the development of the Hysec Process by the Kansai Netsukagaku and Mitsubishi Kakoki companies. The process is outlined and its special features noted. The initial development aim was to obtain high-purity hydrogen from coke oven gas by means of PSA. To achieve this, ways had to be found for removing the impurities in the coke oven gas and the trace amounts of oxygen which are found in the product hydrogen. The resulting hydrogen is 99.9999% pure. 3 references.

Extensive Atrophic Gastritis Increases Intraduodenal Hydrogen Gas

Directory of Open Access Journals (Sweden)

Yoshihisa Urita

2008-01-01

Full Text Available Objective. Gastric acid plays an important part in the prevention of bacterial colonization of the gastrointestinal tract. If these bacteria have an ability of hydrogen (H2 fermentation, intraluminal H2 gas might be detected. We attempted to measure the intraluminal H2 concentrations to determine the bacterial overgrowth in the gastrointestinal tract. Patients and methods. Studies were performed in 647 consecutive patients undergoing upper endoscopy. At the time of endoscopic examination, we intubated the stomach and the descending part of the duodenum without inflation by air, and 20 mL of intraluminal gas samples of both sites was collected through the biopsy channel. Intraluminal H2 concentrations were measured by gas chromatography. Results. Intragastric and intraduodenal H2 gas was detected in 566 (87.5% and 524 (81.0% patients, respectively. The mean values of intragastric and intraduodenal H2 gas were 8.5±15.9 and 13.2±58.0 ppm, respectively. The intraduodenal H2 level was increased with the progression of atrophic gastritis, whereas the intragastric H2 level was the highest in patients without atrophic gastritis. Conclusions. The intraduodenal hydrogen levels were increased with the progression of atrophic gastritis. It is likely that the influence of hypochlorhydria on bacterial overgrowth in the proximal small intestine is more pronounced, compared to that in the stomach.

Hydrogen Production by Steam Reforming of Natural Gas Over Vanadium-Nickel-Alumina Catalysts.

Science.gov (United States)

Yoo, Jaekyeong; Park, Seungwon; Song, Ji Hwan; Song, In Kyu

2018-09-01

A series of vanadium-nickel-alumina (xVNA) catalysts were prepared by a single-step sol-gel method with a variation of vanadium content (x, wt%) for use in the hydrogen production by steam reforming of natural gas. The effect of vanadium content on the physicochemical properties and catalytic activities of xVNA catalysts in the steam reforming of natural gas was investigated. It was found that natural gas conversion and hydrogen yield showed volcano-shaped trends with respect to vanadium content. It was also revealed that natural gas conversion and hydrogen yield increased with decreasing nickel crystallite size.

The production of hydrogen through the uncatalyzed partial oxidation of methane in an internal combustion engine

Energy Technology Data Exchange (ETDEWEB)

Karim, Ghazi A.; Wierzba, I. [Department of Mechanical and Manufacturing Engineering, Schulich School of Engineering, University of Calgary, Calgary (Canada)

2008-04-15

The thermodynamic and kinetic limitations of the uncatalyzed partial oxidation of methane for the production of synthesis gas, which is made up of mostly hydrogen and carbon monoxide in a variety of proportions, are reviewed. It is suggested that such processes can be made to proceed successfully in a conventional internal combustion engine when operated on excessively rich mixtures of methane and oxygenated air. This is achieved while simultaneously producing power and regenerative exhaust gas heating. Experimental results are described that show a dual fuel engine of the compression ignition type with pilot liquid fuel injection can be operated on excessively rich mixtures of methane and air supplemented with oxygen gas to produce hydrogen rich gas with high methane conversion rates. Similarly, a spark ignition engine was reported to be equally capable of such production and performance. It is shown that there are viable prospects for the simultaneous production of synthesis gas in engines with efficient useful mechanical power and exhaust gas regenerative heating. (author)

Laser-driven nuclear-polarized hydrogen internal gas target

International Nuclear Information System (INIS)

Seely, J.; Crawford, C.; Clasie, B.; Xu, W.; Dutta, D.; Gao, H.

2006-01-01

We report the performance of a laser-driven polarized internal hydrogen gas target (LDT) in a configuration similar to that used in scattering experiments. This target used the technique of spin-exchange optical pumping to produce nuclear spin polarized hydrogen gas that was fed into a cylindrical storage (target) cell. We present in this paper the performance of the target, methods that were tried to improve the figure-of-merit (FOM) of the target, and a Monte Carlo simulation of spin-exchange optical pumping. The dimensions of the apparatus were optimized using the simulation and the experimental results were in good agreement with the results from the simulation. The best experimental result achieved was at a hydrogen flow rate of 1.1x10 18 atoms/s, where the sample beam exiting the storage cell had 58.2% degree of dissociation and 50.5% polarization. Based on this measurement, the atomic fraction in the storage cell was 49.6% and the density averaged nuclear polarization was 25.0%. This represents the highest FOM for hydrogen from an LDT and is higher than the best FOM reported by atomic beam sources that used storage cells

Hydrogen from renewable resources - the hundred year commitment

International Nuclear Information System (INIS)

Adamson, K.A.

2004-01-01

During the last decade interest in a potential 'Hydrogen Economy' has increased and is now discussed in main stream literature and political debates. This is largely due to the promise that fuel cell technology, which uses a hydrogen-rich gas, has shown. Though hydrogen can be produced from a number of sources, it is steam reforming of natural gas that has gained a substantial support base, and is seen as an important bridge to a sustainable hydrogen production from renewable energy. What this paper examines is the synergy that exists now between hydrogen from renewable resources and the inception of the fuel cell market. It argues that although the natural gas pathway will be necessary for the short to medium term, there should not be a complete dominance of the production route. The paper also brings together a number of policy documents from the EU and argues that what is needed from the level of the EU is a long term, binding commitment to ensure that the natural gas pathway does not become locked in. (author)

Hydrogen and Hydrogen/Natural Gas Station and Vehicle Operations - 2006 Summary Report

Energy Technology Data Exchange (ETDEWEB)

Francfort; Donald Karner; Roberta Brayer

2006-09-01

This report is a summary of the operations and testing of internal combustion engine vehicles that were fueled with 100% hydrogen and various blends of hydrogen and compressed natural gas (HCNG). It summarizes the operations of the Arizona Public Service Alternative Fuel Pilot Plant, which produces, compresses, and dispenses hydrogen fuel. Other testing activities, such as the destructive testing of a CNG storage cylinder that was used for HCNG storage, are also discussed. This report highlights some of the latest technology developments in the use of 100% hydrogen fuels in internal combustion engine vehicles. Reports are referenced and WWW locations noted as a guide for the reader that desires more detailed information. These activities are conducted by Arizona Public Service, Electric Transportation Applications, the Idaho National Laboratory, and the U.S. Department of Energy’s Advanced Vehicle Testing Activity.

Chemically modified glasses for analysis of hydrogen isotopes by gas-chromatography

International Nuclear Information System (INIS)

Stanciu, Vasile; Stefanescu, Doina

1999-01-01

Hydrogen isotope separation process by such methods as cryogenic distillation or thermal diffusion method is one of the key technologies of the tritium separation from heavy water of CANDU reactors and in the tritium fuel cycle for a thermonuclear fusion reactor. In each process, the analytical techniques for measuring contents of hydrogen isotope mixture are necessary. An extensive experimental research has been carried out in order to produce the most suitable absorbent and define the best operating conditions for selective separation and analysis of hydrogen isotope by gas-chromatography. This paper describes the preparation of adsorbent materials utilised as stationary phase in the gas-chromatographic column for hydrogen isotope separation and treatment (activation) of stationary phase. Modified thermo-resisting glass with Fe(NH 4 ) 2 (SO 4 ) 2 6H 2 O and Cr 2 O 3 , respectively, have been experimentally investigated at 77 K for H 2 , HD and D 2 separation and the results of chromatographic runs are also reported and discussed. The gas-chromatographic apparatus used is composed of a Hewlett-Packard 7620A gas-chromatograph equipped with a gas carrier flow rate controller and a thermal conductivity detector (TCD). The apparatus comprises also a Dewar vessel containing the separation column. The hydrogen isotopes H 2 , HD, D 2 and their mixture have been obtained in our laboratories. The best operating conditions of the adsorbent column Fe (III)/glass and Cr 2 O 3 /glass, i.e. granulometry, column length, pressure-drop along the column, carrier gas flow rate, sample volume have been studied by means of the analysis of the retention times, separation factors and HETP. (authors)

Production of hydrogen gas from novel chemical hydrides

Energy Technology Data Exchange (ETDEWEB)

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

1998-12-01

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

Production of dissociated hydrogen gas by electro-magnetically driven shock

International Nuclear Information System (INIS)

Kondo, Kotaro; Moriyama, Takao; Hasegawa, Jun; Horioka, Kazuhiko; Oguri, Yoshiyuki

2013-01-01

Evaluation of ion stopping power which has a dependence on target temperature and density is an essential issue for heavy-ion-driven high energy density experiment. We focus on experimentally unknown dissociated hydrogen atoms as target for stopping power measurement. The precise measurement of shock wave velocity is required because the dissociated gas is produced by electro-magnetically driven shock. For beam-dissociated hydrogen gas interaction experiment, shock velocity measurement using laser refraction is proposed. (author)

Construction and performance tests of a secondary hydrogen gas cooling system

International Nuclear Information System (INIS)

Sanokawa, K.; Hishida, M.

1980-01-01

With the aim of a multi-purpose use of nuclear energy, such as direct steel-making, an experimental multi-purpose high-temperature gas-cooled reactor (VHTR) is now being developed by the Japan Atomic Energy Research Institute (JAERI). In order to simulate a heat exchanging system between the primary helium gas loop and the secondary reducing gas system of the VHTR, a hydrogen gas loop as a secondary cooling system of the existing helium gas loop was completed in 1977, and was successfully operated for over 2000 hours. The objectives of constructing the H 2 secondary loop were: (1) To get basic knowledge for designing, constructing and operating a high-temperature and high-pressure gas facility; (2) To perform the following tests: (a) hydrogen permeation at the He/H 2 heat exchanger (the surfaces of the heat exchanger tubes are coated by calorizing to reduce hydrogen permeation), (b) thermal performance tests of the He/H 2 heat exchanger and the H 2 /H 2 regenerative heat exchanger, (c) performance test of internal insulation, and (d) performance tests of the components such as a H 2 gas heater and gas purifiers. These tests were carried out at He gas temperature of approximately 1000 0 C, H 2 gas temperature of approximately 900 0 C and gas pressures of approximately 40 kg/cm 2 G, which are almost the same as the operating conditions of the VHTR

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

Hydrogen gas reduces hyperoxic lung injury via the Nrf2 pathway in vivo

Science.gov (United States)

Kawamura, Tomohiro; Wakabayashi, Nobunao; Shigemura, Norihisa; Huang, Chien-Sheng; Masutani, Kosuke; Tanaka, Yugo; Noda, Kentaro; Peng, Ximei; Takahashi, Toru; Billiar, Timothy R.; Okumura, Meinoshin; Toyoda, Yoshiya; Kensler, Thomas W.

2013-01-01

Hyperoxic lung injury is a major concern in critically ill patients who receive high concentrations of oxygen to treat lung diseases. Successful abrogation of hyperoxic lung injury would have a huge impact on respiratory and critical care medicine. Hydrogen can be administered as a therapeutic medical gas. We recently demonstrated that inhaled hydrogen reduced transplant-induced lung injury and induced heme oxygenase (HO)-1. To determine whether hydrogen could reduce hyperoxic lung injury and investigate the underlying mechanisms, we randomly assigned rats to four experimental groups and administered the following gas mixtures for 60 h: 98% oxygen (hyperoxia), 2% nitrogen; 98% oxygen (hyperoxia), 2% hydrogen; 98% balanced air (normoxia), 2% nitrogen; and 98% balanced air (normoxia), 2% hydrogen. We examined lung function by blood gas analysis, extent of lung injury, and expression of HO-1. We also investigated the role of NF-E2-related factor (Nrf) 2, which regulates HO-1 expression, by examining the expression of Nrf2-dependent genes and the ability of hydrogen to reduce hyperoxic lung injury in Nrf2-deficient mice. Hydrogen treatment during exposure to hyperoxia significantly improved blood oxygenation, reduced inflammatory events, and induced HO-1 expression. Hydrogen did not mitigate hyperoxic lung injury or induce HO-1 in Nrf2-deficient mice. These findings indicate that hydrogen gas can ameliorate hyperoxic lung injury through induction of Nrf2-dependent genes, such as HO-1. The findings suggest a potentially novel and applicable solution to hyperoxic lung injury and provide new insight into the molecular mechanisms and actions of hydrogen. PMID:23475767

Production of bioplastics and hydrogen gas by photosynthetic microorganisms

Science.gov (United States)

Yasuo, Asada; Masato, Miyake; Jun, Miyake

1998-03-01

Our efforts have been aimed at the technological basis of photosynthetic-microbial production of materials and an energy carrier. We report here accumulation of poly-(3-hydroxybutyrate) (PHB), a raw material of biodegradable plastics and for production of hydrogen gas, and a renewable energy carrier by photosynthetic microorganisms (tentatively defined as cyanobacteria plus photosynthetic bateria, in this report). A thermophilic cyanobacterium, Synechococcus sp. MA19 that accumulates PHB at more than 20% of cell dry wt under nitrogen-starved conditions was isolated and microbiologically identified. The mechanism of PHB accumulation was studied. A mesophilic Synechococcus PCC7942 was transformed with the genes encoding PHB-synthesizing enzymes from Alcaligenes eutrophus. The transformant accumulated PHB under nitrogen-starved conditions. The optimal conditions for PHB accumulation by a photosynthetic bacterium grown on acetate were studied. Hydrogen production by photosynthetic microorganisms was studied. Cyanobacteria can produce hydrogen gas by nitrogenase or hydrogenase. Hydrogen production mediated by native hydrogenase in cyanobacteria was revealed to be in the dark anaerobic degradation of intracellular glycogen. A new system for light-dependent hydrogen production was targeted. In vitro and in vivo coupling of cyanobacterial ferredoxin with a heterologous hydrogenase was shown to produce hydrogen under light conditions. A trial for genetic trasformation of Synechococcus PCC7942 with the hydrogenase gene from Clostridium pasteurianum is going on. The strong hydrogen producers among photosynthetic bacteria were isolated and characterized. Co-culture of Rhodobacter and Clostriumdium was applied to produce hydrogen from glucose. Conversely in the case of cyanobacteria, genetic regulation of photosynthetic proteins was intended to improve conversion efficiency in hydrogen production by the photosynthetic bacterium, Rhodobacter sphaeroides RV. A mutant acquired by

Preventive Effects of Drinking Hydrogen-Rich Water on Gingival Oxidative Stress and Alveolar Bone Resorption in Rats Fed a High-Fat Diet.

Science.gov (United States)

Yoneda, Toshiki; Tomofuji, Takaaki; Kunitomo, Muneyoshi; Ekuni, Daisuke; Irie, Koichiro; Azuma, Tetsuji; Machida, Tatsuya; Miyai, Hisataka; Fujimori, Kouhei; Morita, Manabu

2017-01-13

Obesity induces gingival oxidative stress, which is involved in the progression of alveolar bone resorption. The antioxidant effect of hydrogen-rich water may attenuate gingival oxidative stress and prevent alveolar bone resorption in cases of obesity. We examined whether hydrogen-rich water could suppress gingival oxidative stress and alveolar bone resorption in obese rats fed a high-fat diet. Male Fischer 344 rats ( n = 18) were divided into three groups of six rats each: a control group (fed a regular diet and drinking distilled water) and two experimental groups (fed a high-fat diet and drinking distilled water or hydrogen-rich water). The level of 8-hydroxydeoxyguanosine was determined to evaluate oxidative stress. The bone mineral density of the alveolar bone was analyzed by micro-computerized tomography. Obese rats, induced by a high-fat diet, showed a higher gingival level of 8-hydroxydeoxyguanosine and a lower level of alveolar bone density compared to the control group. Drinking hydrogen-rich water suppressed body weight gain, lowered gingival level of 8-hydroxydeoxyguanosine, and reduced alveolar bone resorption in rats on a high-fat diet. The results indicate that hydrogen-rich water could suppress gingival oxidative stress and alveolar bone resorption by limiting obesity.

Membrane reforming in converting natural gas to hydrogen (part one)

Energy Technology Data Exchange (ETDEWEB)

Barba, D; Giacobbe, F; De Cesaris, A [Faculty of Chemical Engineering and Materials, University of L' Aquila (Italy); Farace, A; Iaquaniello, G; Pipino, A [TECHNIP-KTI S.p.a., Rome (Italy)

2008-07-15

Membrane reforming reactors (MRR) could play a key role in converting natural gas into hydrogen. The major advantage of MRR architecture is the possibility to shift the chemical equilibrium toward the right-hand side of the reaction, improving hydrogen production and allowing, the same time high methane conversion at relatively low temperatures such as 650 C. Such a low operating temperature makes it possible to locate the MRR downstream of a gas turbine, achieving an efficient hybrid system (power+hydrogen) with a significant reduction in energy consumption (around 10%). This paper discusses the whole innovative architecture where conventional tubular reforming is integrated with hydrogen permeable palladium membrane separators. The fundamental concepts are analyzed and integrated into a process scheme; the structural effects of variables design such as reactor temperature outlet, S/C ratio and recycle ratio throughout pinch and sensitivity analysis are described, and a comparison of the process economics with conventional hydrogen technology is presented at the end of the second part of this paper. The production of highly reliable, defect-free and reproducible, Pd-alloy membranes for selective hydrogen separation is a key issue in the proposed hybrid architecture. (author)

The use of the natural-gas pipeline infrastructure for hydrogen transport in a changing market structure

International Nuclear Information System (INIS)

Haeseldonckx, Dries; D'haeseleer, William

2007-01-01

In this paper, the transport and distribution aspects of hydrogen during the transition period towards a possible full-blown hydrogen economy are carefully looked at. Firstly, the energetic and material aspects of hydrogen transport through the existing natural-gas (NG) pipeline infrastructure is discussed. Hereby, only the use of centrifugal compressors and the short-term security of supply seem to constitute a problem for the NG to hydrogen transition. Subsequently, the possibility of percentwise mixing of hydrogen into the NG bulk is dealt with. Mixtures containing up to 17 vol% of hydrogen should not cause difficulties. As soon as more hydrogen is injected, replacement of end-use applications and some pipelines will be necessary. Finally, the transition towards full-blown hydrogen transport in (previously carrying) NG pipelines is treated. Some policy guidelines are offered, both in a regulated and a liberalised energy (gas) market. As a conclusion, it can be stated that the use of hydrogen-natural gas mixtures seems well suited for the transition from natural gas to hydrogen on a distribution (low pressure) level. However, getting the hydrogen gas to the distribution grid, by means of the transport grid, remains a major issue. In the end, the structure of the market, regulated or liberalised, turns out not to be important. (author)

Hydrogen generation from natural gas for the fuel cell systems of tomorrow

Science.gov (United States)

Dicks, Andrew L.

In most cases hydrogen is the preferred fuel for use in the present generation of fuel cells being developed for commercial applications. Of all the potential sources of hydrogen, natural gas offers many advantages. It is widely available, clean, and can be converted to hydrogen relatively easily. When catalytic steam reforming is used to generate hydrogen from natural gas, it is essential that sulfur compounds in the natural gas are removed upstream of the reformer and various types of desulfurisation processes are available. In addition, the quality of fuel required for each type of fuel cell varies according to the anode material used, and the cell temperature. Low temperature cells will not tolerate high concentrations of carbon monoxide, whereas the molten fuel cell (MCFC) and solid oxide fuel cell (SOFC) anodes contain nickel on which it is possible to electrochemically oxidise carbon monoxide directly. The ability to internally reform fuel gas is a feature of the MCFC and SOFC. Internal reforming can give benefits in terms of increased electrical efficiency owing to the reduction in the required cell cooling and therefore parasitic system losses. Direct electrocatalysis of hydrocarbon oxidation has been the elusive goal of fuel cell developers over many years and recent laboratory results are encouraging. This paper reviews the principal methods of converting natural gas into hydrogen, namely catalytic steam reforming, autothermic reforming, pyrolysis and partial oxidation; it reviews currently available purification techniques and discusses some recent advances in internal reforming and the direct use of natural gas in fuel cells.

The production of high dose hydrogen gas by the AMS-H-01 for treatment of disease

OpenAIRE

Richard Camara; Lei Huang; John H Zhang

2016-01-01

Hydrogen gas is a new and promising treatment option for a variety of diseases including stroke. Here, we introduce the AMS-H-01, a medically approved machine capable of safely producing ~66% hydrogen gas. Furthermore, we propose the significance of this machine in the future of hydrogen gas research.

[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.

Simultaneous purification and storage of hydrogen

Energy Technology Data Exchange (ETDEWEB)

Hynek, S.; Fuller, W.; Weber, R.; Carlson, E. [Arthur D. Little, Inc., Cambridge, MA (United States)

1998-08-01

Specially coated magnesium particles have been shown to selectively absorb hydrogen from a hydrogen-rich gas stream such as reformate. These coated magnesium particles can store the absorbed hydrogen as required and subsequently deliver pure hydrogen, just as uncoated magnesium particles can. These coated magnesium particles could be used in a device that accepts a steady stream of reformate, as from a methane reformer, stores the selectively absorbed hydrogen indefinitely, and delivers purified hydrogen on demand. Unfortunately, this coating (magnesium nitride) has been shown to degrade over a period of several weeks, so that the magnesium within evidences progressively lower storage capacity. The authors are investigating two other coatings, one of which might be applicable to hydridable metals other than magnesium, to replace magnesium nitride.

Magnetic resonance studies of atomic hydrogen gas at low temperatures

International Nuclear Information System (INIS)

Hardy, W.N.; Morrow, M.; Jochemsen, R.; Statt, B.W.; Kubik, P.R.; Marsolais, R.M.; Berlinsky, A.J.; Landesman, A.

1980-01-01

Using a pulsed low temperature discharge in a closed cell containing H 2 and 4 He, we have been able to store a low density (approximately 10 12 atoms/cc) gas of atomic hydrogen for periods of order one hour in zero magnetic field and T=1 K. Pulsed magnetic resonance at the 1420 MHz hyperfine transition has been used to study a number of the properties of the gas, including the recombination rate H + H + 4 He→H 2 + 4 He, the hydrogen spin-exchange relaxation rates, the diffusion coefficient of H in 4 He gas and the pressure shift of the hyperfine frequency due to the 4 He buffer gas. Here we discuss the application of hyperfine frequency shifts as a probe of the H-He potential, and as a means for determining the binding energy of H on liquid helium

Attenuation of hydrogen radicals traveling under flowing gas conditions through tubes of different materials

International Nuclear Information System (INIS)

Grubbs, R.K.; George, S.M.

2006-01-01

Hydrogen radical concentrations traveling under flowing gas conditions through tubes of different materials were measured using a dual thermocouple probe. The source of the hydrogen radicals was a toroidal radio frequency plasma source operating at 2.0 and 3.3 kW for H 2 pressures of 250 and 500 mTorr, respectively. The dual thermocouple probe was comprised of exposed and covered Pt/Pt13%Rh thermocouples. Hydrogen radicals recombined efficiently on the exposed thermocouple and the energy of formation of H 2 heated the thermocouple. The second thermocouple was covered by glass and was heated primarily by the ambient gas. The dual thermocouple probe was translated and measured temperatures at different distances from the hydrogen radical source. These temperature measurements were conducted at H 2 flow rates of 35 and 75 SCCM (SCCM denotes cubic centimeter per minute at STP) inside cylindrical tubes made of stainless steel, aluminum, quartz, and Pyrex. The hydrogen radical concentrations were obtained from the temperatures of the exposed and covered thermocouples. The hydrogen concentration decreased versus distance from the plasma source. After correcting for the H 2 gas flow using a reference frame transformation, the hydrogen radical concentration profiles yielded the atomic hydrogen recombination coefficient, γ, for the four materials. The methodology of measuring the hydrogen radical concentrations, the analysis of the results under flowing gas conditions, and the determination of the atomic hydrogen recombination coefficients for various materials will help facilitate the use of hydrogen radicals for thin film growth processes

Warm Pressurant Gas Effects on the Liquid Hydrogen Bubble Point

Science.gov (United States)

Hartwig, Jason W.; McQuillen, John B.; Chato, David J.

2013-01-01

This paper presents experimental results for the liquid hydrogen bubble point tests using warm pressurant gases conducted at the Cryogenic Components Cell 7 facility at the NASA Glenn Research Center in Cleveland, Ohio. The purpose of the test series was to determine the effect of elevating the temperature of the pressurant gas on the performance of a liquid acquisition device. Three fine mesh screen samples (325 x 2300, 450 x 2750, 510 x 3600) were tested in liquid hydrogen using cold and warm noncondensible (gaseous helium) and condensable (gaseous hydrogen) pressurization schemes. Gases were conditioned from 0 to 90 K above the liquid temperature. Results clearly indicate a degradation in bubble point pressure using warm gas, with a greater reduction in performance using condensable over noncondensible pressurization. Degradation in the bubble point pressure is inversely proportional to screen porosity, as the coarsest mesh demonstrated the highest degradation. Results here have implication on both pressurization and LAD system design for all future cryogenic propulsion systems. A detailed review of historical heated gas tests is also presented for comparison to current results.

Hydrogen Addition for Improved Lean Burn Capability on Natural Gas Engine

Energy Technology Data Exchange (ETDEWEB)

Andersson, Tobias [Lund Inst. of Technology (Sweden). Dept. of Heat and Power Engineering

2002-12-01

Lean burn spark ignition (SI) engines powered by natural gas is an attractive alternative to the Diesel engine, especially in urban traffic, where reduction of tailpipe emissions are of great importance. A major benefit is the large reduction in soot (PM). Lean burn spark ignition (SI) engines yield high fuel conversion efficiency and also relatively low NO{sub x} emissions at full load. In order to improve the engine operating characteristics at lower loads, the {lambda}-value is normally reduced to some degree, with increased NO{sub x} emissions and reduced efficiency as a result. This is a drawback for the lean burn engines, especially in urban applications such as in city buses and distribution trucks for urban use. So, it is desirable to find ways to extend the lean limit at low loads. One way to improve these part load properties is to add hydrogen to the natural gas in order to improve the combustion characteristics of the fuel. It is possible to extend the lean limit of a natural gas engine by addition of hydrogen to the primary fuel. This report presents measurements made on a single cylinder 1.6 liter natural gas engine. Two combustion chambers, one slow and one fast burning, were tested with various amounts of hydrogen (0 to 20 %-vol) added to natural gas. Three operating conditions were investigated for each combustion chamber and each hydrogen content level; idle, wide open throttle (WOT) and a high load condition (simulated turbo charging). For all three operating conditions, the air/fuel ratio was varied between stoichiometric and the lean limit. For each operating point, the ignition timing was swept in order to find maximum brake torque (MBT) timing. In some cases were the ignition timing limited by knock. Heat release rate calculations were made in order to assess the influence of hydrogen addition on burn rate. Addition of hydrogen showed an increase in burn rate for both combustion chambers, resulting in more stable combustion close to the lean

Hydrogen Separation by Natural Zeolite Composite Membranes: Single and Multicomponent Gas Transport.

Science.gov (United States)

Farjoo, Afrooz; Kuznicki, Steve M; Sadrzadeh, Mohtada

2017-10-06

Single and multicomponent gas permeation tests were used to evaluate the performance of metal-supported clinoptilolite membranes. The efficiency of hydrogen separation from lower hydrocarbons (methane, ethane, and ethylene) was studied within the temperature and pressure ranges of 25-600 °C and 110-160 kPa, respectively. The hydrogen separation factor was found to reduce noticeably in the gas mixture compared with single gas experiments at 25 °C. The difference between the single and multicomponent gas results decreased as the temperature increased to higher than 300 °C, which is when the competitive adsorption-diffusion mechanism was replaced by Knudsen diffusion or activated diffusion mechanisms. To evaluate the effect of gas adsorption, the zeolite surface isotherms of each gas in the mixture were obtained from 25 °C to 600 °C. The results indicated negligible adsorption of individual gases at temperatures higher than 300 °C. Increasing the feed pressure resulted in a higher separation efficiency for the individual gases compared with the multicomponent mixture, due to the governing effect of the adsorptive mechanism. This study provides valuable insight into the application of natural zeolites for the separation of hydrogen from a mixture of hydrocarbons.

Apparatus and method for treating pollutants in a gas using hydrogen peroxide and UV light

Science.gov (United States)

Cooper, Charles David (Inventor); Clausen, Christian Anthony (Inventor)

2005-01-01

An apparatus for treating pollutants in a gas may include a source of hydrogen peroxide, and a treatment injector for creating and injecting dissociated hydrogen peroxide into the flow of gas. The treatment injector may further include an injector housing having an inlet, an outlet, and a hollow interior extending therebetween. The inlet may be connected in fluid communication with the source of hydrogen peroxide so that hydrogen peroxide flows through the hollow interior and toward the outlet. At least one ultraviolet (UV) lamp may be positioned within the hollow interior of the injector housing. The at least one UV lamp may dissociate the hydrogen peroxide flowing through the tube. The dissociated hydrogen peroxide may be injected into the flow of gas from the outlet for treating pollutants, such as nitrogen oxides.

Serpentinization and the origin of hydrogen gas in Kansas

Energy Technology Data Exchange (ETDEWEB)

Coveney, R.M. Jr.; Goebel, E.D.; Zeller, E.J.; Dreschhoff, G.A.M.; Angino, E.E.

1987-01-01

Hydrogen gas occurs in ten Kansas wells near the Mid-Continent rift system. Since 1982, two wells have yielded small amounts of gases containing an average of 29-37 mole % H/sub 2/, the remainder being chiefly N/sub 2/ with only traces of hydrocarbons. Isotopic compositions for hydrogen (delta D = -740 to -836 per thousand) imply near-ambient (about 10/sup 0/C) equilibration temperatures for the gases, which are among the most deuterium-depleted in nature and resemble the H/sub 2/-rich gases described from ophiolites in Oman. Isotopic values for the Kansas N/sub 2/ differ slightly from those of the atmosphere, but not enough to rule out an atmospheric origin. Because they are low in CH/sub 4/ and CO/sub 2/, expected byproducts of biogenic activity, the gases are probably abiogenic in origin. The existence of such gases near a major rift system, containing mafic rocks, and not far from known kimberlites is consistent with an origin from reactions involving Fe/sup +2/ oxidation, for example during serpentinization. Because the gases may be associated with kimberlites and deep-seated rifting, mantle outgassing is possible, but such an origin would be difficult to reconcile with the low isotopic temperatures. The H/sub 2/ gases from Kansas (and elsewhere) seem to be too low in pressure to have commercial value. However, neither the Kansas gases nor those from other H/sub 2/ occurrences have been adequately examined to assess their importance as potential resources. 4 figures, 3 tables.

FIRST OPERATING RESULTS OF A DYNAMIC GAS BEARING TURBINE IN AN INDUSTRIAL HYDROGEN LIQUEFIER

International Nuclear Information System (INIS)

Bischoff, S.; Decker, L.

2010-01-01

Hydrogen has been brought into focus of industry and public since fossil fuels are depleting and costs are increasing dramatically. Beside these issues new high-tech processes in the industry are in need for hydrogen at ultra pure quality. To achieve these requirements and for efficient transportation, hydrogen is liquefied in industrial plants. Linde Gas has commissioned a new 5.5 TPD Hydrogen liquefier in Leuna, Germany, which has been engineered and supplied by Linde Kryotechnik. One of the four expansion turbines installed in the liquefaction process is equipped with dynamic gas bearings. Several design features and operational characteristics of this application will be discussed. The presentation will include results of efficiency and operational reliability that have been determined from performance tests. The advantages of the Linde dynamic gas bearing turbine for future use in hydrogen liquefaction plants will be shown.

Inspection of the hydrogen gas pressure with metal shield by cold neutron radiography at CMRR

Energy Technology Data Exchange (ETDEWEB)

Li, Hang; Cao, Chao; Huo, Heyong; Wang, Sheng; Wu, Yang; Yin, Wei; Sun, Yong; Liu, Bin; Tang, Bin [Institute of Nuclear Physics and Chemistry, Chinese Academy of Engineering Physics, Mianyang (China); Key Laboratory of Neutron Physics, Chinese Academy of Engineering Physics, Mianyang (China)

2017-04-11

The inspection of the process of gas pressure change is important for some applications (e.g. gas tank stockpile or two phase fluid model) which need quantitative and non-touchable measurement. Neutron radiography provides a suitable tool for such investigations with nice resolution. The quantitative cold neutron radiography (CNR) is developed at China Mianyang Research Reactor (CMRR) to measure the hydrogen gas pressure with metal shield. Because of the high sensitivity to hydrogen, even small change of the hydrogen pressure can be inspected by CNR. The dark background and scattering neutron effect are both corrected to promote measurement precision. The results show that CNR can measure the hydrogen gas pressure exactly and the pressure value average relative error between CNR and barometer is almost 1.9%.

Determination of hydrogen in uranium-niobium-zirconium alloy by inert-gas fusion

International Nuclear Information System (INIS)

Carden, W.F.

1979-12-01

An improved method has been developed using inert-gas fusion for determining the hydrogen content in uranium-niobium-zirconium (U-7.5Nb-2.5Zr) alloy. The method is applicable to concentrations of hydrogen ranging from 1 to 250 micrograms per gram and may be adjusted for analysis of greater hydrogen concentrations. Hydrogen is determined using a hydrogen determinator. The limit of error for a single determination at the 95%-confidence level (at the 3.7-μg/g-hydrogen level) is +-1.4 micrograms per gram hydrogen

Advances of zeolite based membrane for hydrogen production via water gas shift reaction

Science.gov (United States)

Makertihartha, I. G. B. N.; Zunita, M.; Rizki, Z.; Dharmawijaya, P. T.

2017-07-01

Hydrogen is considered as a promising energy vector which can be obtained from various renewable sources. However, an efficient hydrogen production technology is still challenging. One technology to produce hydrogen with very high capacity with low cost is through water gas shift (WGS) reaction. Water gas shift reaction is an equilibrium reaction that produces hydrogen from syngas mixture by the introduction of steam. Conventional WGS reaction employs two or more reactors in series with inter-cooling to maximize conversion for a given volume of catalyst. Membrane reactor as new technology can cope several drawbacks of conventional reactor by removing reaction product and the reaction will favour towards product formation. Zeolite has properties namely high temperature, chemical resistant, and low price makes it suitable for membrane reactor applications. Moreover, it has been employed for years as hydrogen selective layer. This review paper is focusing on the development of membrane reactor for efficient water gas shift reaction to produce high purity hydrogen and carbon dioxide. Development of membrane reactor is discussed further related to its modification towards efficient reaction and separation from WGS reaction mixture. Moreover, zeolite framework suitable for WGS membrane reactor will be discussed more deeply.

Evolution of helium rich stars with hydrogen burning

International Nuclear Information System (INIS)

Roeser, M.

1975-08-01

Evolutionary tracks of stars with an initial chemical composition X = 0.100, Y = 0.8790, Z = 0.021 are calculated for masses of 0.35 M(sun), 0.66 M(sun), 1.00 M(sun), 2.00 M(sun), and 5.00 M(sun) and with X = 0.302, Y = 0.677, Z = 0.021 for masses of 1.00 M(sun), 3.00 M(sun), and 5.00 M(sun). The evolution is followed from hydrogen burning to helium burning and to carbon burning when the occasion arises. The data of evolution are presented and compared with normal Population I-stars. The helium rich stars show higher effective temperatures, much higher luminosities and therefore shorter time scales. They are situated in regions of the HR-diagram where observed helium stars are found. (orig.) [de

Hydrogen Gas Inhalation Attenuates Seawater Instillation-Induced Acute Lung Injury via the Nrf2 Pathway in Rabbits.

Science.gov (United States)

Diao, Mengyuan; Zhang, Sheng; Wu, Lifeng; Huan, Le; Huang, Fenglou; Cui, Yunliang; Lin, Zhaofen

2016-12-01

Seawater instillation-induced acute lung injury involves oxidative stress and apoptosis. Although hydrogen gas inhalation is reportedly protective in multiple types of lung injury, the effect of hydrogen gas inhalation on seawater instillation-induced acute lung injury remains unknown. This study investigated the effect of hydrogen gas on seawater instillation-induced acute lung injury and explored the mechanisms involved. Rabbits were randomly assigned to control, hydrogen (2 % hydrogen gas inhalation), seawater (3 mL/kg seawater instillation), and seawater + hydrogen (3 mL/kg seawater instillation + 2 % hydrogen gas inhalation) groups. Arterial partial oxygen pressure and lung wet/dry weight ratio were detected. Protein content in bronchoalveolar lavage fluid (BALF) and serum as well as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 levels were determined. Hematoxylin-eosin staining was used to monitor changes in lung specimens, and malondialdehyde (MDA) content and myeloperoxidase (MPO) activity were assayed. In addition, NF-E2-related factor (Nrf) 2 and heme oxygenase (HO)-1 mRNA and protein expression were measured, and apoptosis was assessed by measuring caspase-3 expression and using terminal deoxy-nucleotidyl transferase dUTP nick end-labeling (TUNEL) staining. Hydrogen gas inhalation markedly improved lung endothelial permeability and decreased both MDA content and MPO activity in lung tissue; these changes were associated with decreases in TNF-α, IL-1β, and IL-6 in BALF. Hydrogen gas also alleviated histopathological changes and cell apoptosis. Moreover, Nrf2 and HO-1 expressions were significantly activated and caspase-3 expression was inhibited. These results demonstrate that hydrogen gas inhalation attenuates seawater instillation-induced acute lung injury in rabbits and that the protective effects observed may be related to the activation of the Nrf2 pathway.

DEMONSTRATION BULLETIN: GAS-PHASE CHEMICAL REDUCTION - ECO LOGIC INTERNATIONAL, INC.

Science.gov (United States)

The patented Eco Logic Process employs a gas-phase reduction reaction of hydrogen with organic and chlorinated organic compounds at elevated temperatures to convert aqueous and oily hazardous contaminants into a hydrocarbon-rich gas product. After passing through a scrubber, the ...

Hydrogen Separation by Natural Zeolite Composite Membranes: Single and Multicomponent Gas Transport

Directory of Open Access Journals (Sweden)

Afrooz Farjoo

2017-10-01

Full Text Available Single and multicomponent gas permeation tests were used to evaluate the performance of metal-supported clinoptilolite membranes. The efficiency of hydrogen separation from lower hydrocarbons (methane, ethane, and ethylene was studied within the temperature and pressure ranges of 25–600 °C and 110–160 kPa, respectively. The hydrogen separation factor was found to reduce noticeably in the gas mixture compared with single gas experiments at 25 °C. The difference between the single and multicomponent gas results decreased as the temperature increased to higher than 300 °C, which is when the competitive adsorption–diffusion mechanism was replaced by Knudsen diffusion or activated diffusion mechanisms. To evaluate the effect of gas adsorption, the zeolite surface isotherms of each gas in the mixture were obtained from 25 °C to 600 °C. The results indicated negligible adsorption of individual gases at temperatures higher than 300 °C. Increasing the feed pressure resulted in a higher separation efficiency for the individual gases compared with the multicomponent mixture, due to the governing effect of the adsorptive mechanism. This study provides valuable insight into the application of natural zeolites for the separation of hydrogen from a mixture of hydrocarbons.

Organic richness and gas generation potential of Permian Barren

Indian Academy of Sciences (India)

The organic geochemistry of shales in terms of its organic richness, hydrocarbon source potential, thermal maturity, depositional environment, etc., are essential stipulations for shale gas resources assessment. In this study, a total of 32 core samples of Permian Barren Measures from four boreholes in Raniganj field of ...

Empirical Method to Estimate Hydrogen Embrittlement of Metals as a Function of Hydrogen Gas Pressure at Constant Temperature

Science.gov (United States)

Lee, Jonathan A.

2010-01-01

High pressure Hydrogen (H) gas has been known to have a deleterious effect on the mechanical properties of certain metals, particularly, the notched tensile strength, fracture toughness and ductility. The ratio of these properties in Hydrogen as compared to Helium or Air is called the Hydrogen Environment Embrittlement (HEE) Index, which is a useful method to classify the severity of H embrittlement and to aid in the material screening and selection for safety usage H gas environment. A comprehensive world-wide database compilation, in the past 50 years, has shown that the HEE index is mostly collected at two conveniently high H pressure points of 5 ksi and 10 ksi near room temperature. Since H embrittlement is directly related to pressure, the lack of HEE index at other pressure points has posed a technical problem for the designers to select appropriate materials at a specific H pressure for various applications in aerospace, alternate and renewable energy sectors for an emerging hydrogen economy. Based on the Power-Law mathematical relationship, an empirical method to accurately predict the HEE index, as a function of H pressure at constant temperature, is presented with a brief review on Sievert's law for gas-metal absorption.

Development of the Raman lidar system for remote hydrogen gas detection

Energy Technology Data Exchange (ETDEWEB)

Choi, In Young; Baik, Sung Hoon; Park, Seung Kyu; Park, Nak Gyu; Choi, Young Soo [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

2016-10-15

Detection of hydrogen (H{sub 2}) gas leakage is very important for safety of the nuclear power plant because H{sub 2} gas is very flammable and explosive. H{sub 2} gas is generated by oxidizing the nuclear fuel cladding during the critical accident and generated H{sub 2} gas leads to serious secondary damages in the containment building of nuclear power plant. Thus, various H{sub 2} gas detection techniques are used in the nuclear power plant such as catalytic combustion sensors, semiconducting oxide sensors, thermal conductivity sensors and electrochemical sensor. A Raman lidar (Light Detection And Ranging) system for remote detection of the H{sub 2} gas can cover the area in the containment building of a nuclear power plant. H{sub 2} gas has a very strong Raman Effect, and H{sub 2} Raman cells have been widely used for laser wavelength conversion. In this study, Raman lidar system was developed for H{sub 2} gas detection used in the containment building of nuclear power plant. In this study, remote hydrogen gas detection devices and measuring algorithm are developed by using the Raman lidar method. Through the experiment, we proved that our developed Raman lidar system was possible to measure the N{sub 2} and H{sub 2} gas scattering signal remotely.

Thermonuclear runaways in thick hydrogen rich envelopes of neutron stars

Science.gov (United States)

Starrfield, S. G.; Kenyon, S.; Truran, J. W.; Sparks, W. M.

1981-01-01

A Lagrangian, fully implicit, one dimensional hydrodynamic computer code was used to evolve thermonuclear runaways in the accreted hydrogen rich envelopes of 1.0 Msub solar neutron stars with radii of 10 km and 20 km. Simulations produce outbursts which last from about 750 seconds to about one week. Peak effective temeratures and luninosities were 26 million K and 80 thousand Lsub solar for the 10 km study and 5.3 millison and 600 Lsub solar for the 20 km study. Hydrodynamic expansion on the 10 km neutron star produced a precursor lasting about one ten thousandth seconds.

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.

Variable composition hydrogen/natural gas mixtures for increased engine efficiency and decreased emissions

Energy Technology Data Exchange (ETDEWEB)

Sierens, R.; Rosseel, E.

2000-01-01

It is well known that adding hydrogen to natural gas extends the lean limit of combustion and that in this way extremely low emission levels can be obtained: even the equivalent zero emission vehicle (EZEV) requirements can be reached. The emissions reduction is especially important at light engine loads. In this paper results are presented for a GM V8 engine. Natural gas, pure hydrogen and different blends of these two fuels have been tested. The fuel supply system used provides natural gas/hydrogen mixtures in variable proportion, regulated independently of the engine operating condition. The influence of the fuel composition on the engine operating characteristics and exhaust emissions has been examined, mainly but not exclusively for 10 and 20% hydrogen addition. At least 10% hydrogen addition is necessary for a significant improvement in efficiency. Due to the conflicting requirements for low hydrocarbons and low NO{sub x} determining the optimum hythane composition is not straight-forward. For hythane mixtures with a high hydrogen fraction, it is found that a hydrogen content of 80% or less guarantees safe engine operation (no backfire nor knock), whatever the air excess factor. It is shown that to obtain maximum engine efficiency for the whole load range while taking low exhaust emissions into account, the mixture composition should be varied with respect to engine load.

Lifecycle impacts of natural gas to hydrogen pathways on urban air quality

International Nuclear Information System (INIS)

Wang, Guihua; Ogden, Joan M.; Nicholas, Michael A.

2007-01-01

In this paper we examine the potential air quality impacts of hydrogen transportation fuel from a lifecycle analysis perspective, including impacts from fuel production, delivery, and vehicle use. We assume that hydrogen fuel cell vehicles are introduced in a specific region, Sacramento County, California. We consider two levels of market penetration where 9% or 20% of the light duty fleet are hydrogen fuel cell vehicles. The following three natural gas to hydrogen supply pathways are assessed in detail and compared in terms of emissions and the resulting changes in ambient air quality: (1) onsite hydrogen production; (2) centralized hydrogen production with gaseous hydrogen pipeline delivery systems; and (3) centralized hydrogen production with liquid hydrogen truck delivery systems. All the pathways examined use steam methane reforming (SMR) of natural gas to produce hydrogen. The source contributions to incremental air pollution are estimated and compared among hydrogen pathways. All of the hydrogen pathways result in extremely low contributions to ambient air concentrations of NO x , CO, particulates, and SO x , typically less than 0.1% of the current ambient pollution for both levels of market penetration. Among the hydrogen supply options, it is found that the central SMR with pipeline delivery systems is the lowest pollution option available provided the plant is located to avoid transport of pollutants into the city via prevailing winds. The onsite hydrogen pathway is comparable to the central hydrogen pathway with pipeline systems in terms of the resulting air pollution. The pathway with liquid hydrogen trucks has a greater impact on air quality relative to the other pathways due to emissions associated with diesel trucks and electricity consumption to liquefy hydrogen. However, all three hydrogen pathways result in negligible air pollution in the region. (author)

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

Heat pump cycle by hydrogen-absorbing alloys to assist high-temperature gas-cooled reactor in producing hydrogen

International Nuclear Information System (INIS)

Satoshi, Fukada; Nobutaka, Hayashi

2010-01-01

A chemical heat pump system using two hydrogen-absorbing alloys is proposed to utilise heat exhausted from a high-temperature source such as a high-temperature gas-cooled reactor (HTGR), more efficiently. The heat pump system is designed to produce H 2 based on the S-I cycle more efficiently. The overall system proposed here consists of HTGR, He gas turbines, chemical heat pumps and reaction vessels corresponding to the three-step decomposition reactions comprised in the S-I process. A fundamental research is experimentally performed on heat generation in a single bed packed with a hydrogen-absorbing alloy that may work at the H 2 production temperature. The hydrogen-absorbing alloy of Zr(V 1-x Fe x ) 2 is selected as a material that has a proper plateau pressure for the heat pump system operated between the input and output temperatures of HTGR and reaction vessels of the S-I cycle. Temperature jump due to heat generated when the alloy absorbs H 2 proves that the alloy-H 2 system can heat up the exhaust gas even at 600 deg. C without any external mechanical force. (authors)

Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic Matter

KAUST Repository

Logan, Bruce E.

2008-12-01

The use of electrochemically active bacteria to break down organic matter, combined with the addition of a small voltage (>0.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield of hydrogen gas. While microbial electrolysis was invented only a few years ago, rapid developments have led to hydrogen yields approaching 100%, energy yields based on electrical energy input many times greater than that possible by water electrolysis, and increased gas production rates. MECs used to make hydrogen gas are similar in design to microbial fuel cells (MFCs) that produce electricity, but there are important differences in architecture and analytical methods used to evaluate performance. We review here the materials, architectures, performance, and energy efficiencies of these MEC systems that show promise as a method for renewable and sustainable energy production, and wastewater treatment. © 2008 American Chemical Society.

Dominant rate process of silicon surface etching by hydrogen chloride gas

International Nuclear Information System (INIS)

Habuka, Hitoshi; Suzuki, Takahiro; Yamamoto, Sunao; Nakamura, Akio; Takeuchi, Takashi; Aihara, Masahiko

2005-01-01

Silicon surface etching and its dominant rate process are studied using hydrogen chloride gas in a wide concentration range of 1-100% in ambient hydrogen at atmospheric pressure in a temperature range of 1023-1423 K, linked with the numerical calculation accounting for the transport phenomena and the surface chemical reaction in the entire reactor. The etch rate, the gaseous products and the surface morphology are experimentally evaluated. The dominant rate equation accounting for the first-order successive reactions at silicon surface by hydrogen chloride gas is shown to be valid. The activation energy of the dominant surface process is evaluated to be 1.5 x 10 5 J mol - 1 . The silicon deposition by the gaseous by-product, trichlorosilane, is shown to have a negligible influence on the silicon etch rate

Fuel hydrogen retention of tungsten and the reduction by inert gas glow discharges

Energy Technology Data Exchange (ETDEWEB)

Hino, T., E-mail: tomhino@qe.eng.hokudai.ac.jp [Laboratory of Plasma Physics and Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Yamauchi, Y.; Kimura, Y. [Laboratory of Plasma Physics and Engineering, Hokkaido University, Sapporo 060-8628 (Japan); Nishimura, K. [National Institute for Fusion Science, Toki-shi, Gifu-ken 509-5292 (Japan); Ueda, Y. [Graduate School of Engineering, Osaka University, Suita-shi 565-0872 (Japan)

2012-08-15

Highlights: Black-Right-Pointing-Pointer The performances of inert gas glow discharges for reduction of fuel hydrogen retention in tungsten were systematically investigated. Black-Right-Pointing-Pointer For the tungsten with rough surface structure, the reduction of fuel hydrogen retention by inert gas discharges is quite small. Black-Right-Pointing-Pointer The deuterium glow discharge is quite useful to reduce the tritium retention in plasma facing walls in fusion reactor. Black-Right-Pointing-Pointer The wall baking with temperature higher than 700-800 K is also useful to reduce the tritium retention in plasma facing walls. - Abstract: Polycrystalline tungsten was exposed to deuterium glow discharge followed by He, Ne or Ar glow discharge. The amount of retained deuterium in the tungsten was measured using residual gas analysis. The amount of desorbed deuterium during the inert gas glow discharge was also measured. The amount of retained deuterium was 2-3 times larger compared with a case of stainless steel. The ratios of desorbed amount of deuterium by He, Ne and Ar glow discharges were 4.6, 3.1 and 2.9%, respectively. These values were one order of magnitude smaller compared with the case of stainless steel. The inert gas glow discharge is not suitable to reduce the fuel hydrogen retention for tungsten walls. However, the wall baking with a temperature higher than 700 K is suitable to reduce the fuel hydrogen retention. It is also shown that the use of deuterium glow discharge is effective to reduce the in-vessel tritium inventory in fusion reactors through the hydrogen isotope exchange.

Development and industrial application of catalyzer for low-temperature hydrogenation hydrolysis of Claus tail gas

Directory of Open Access Journals (Sweden)

Honggang Chang

2015-10-01

Full Text Available With the implementation of more strict national environmental protection laws, energy conservation, emission reduction and clean production will present higher requirements for sulfur recovery tail gas processing techniques and catalyzers. As for Claus tail gas, conventional hydrogenation catalyzers are gradually being replaced by low-temperature hydrogenation catalyzers. This paper concentrates on the development of technologies for low-temperature hydrogenation hydrolysis catalyzers, preparation of such catalyzers and their industrial application. In view of the specific features of SO2 hydrogenation and organic sulfur hydrolysis during low-temperature hydrogenation, a new technical process involving joint application of hydrogenation catalyzers and hydrolysis catalyzers was proposed. In addition, low-temperature hydrogenation catalyzers and low-temperature hydrolysis catalyzers suitable for low-temperature conditions were developed. Joint application of these two kinds of catalyzers may reduce the inlet temperatures in the conventional hydrogenation reactors from 280 °C to 220 °C, at the same time, hydrogenation conversion rates of SO2 can be enhanced to over 99%. To further accelerate the hydrolysis rate of organic sulfur, the catalyzers for hydrolysis of low-temperature organic sulfur were developed. In lab tests, the volume ratio of the total sulfur content in tail gas can be as low as 131 × 10−6 when these two kinds of catalyzers were used in a proportion of 5:5 in volumes. Industrial application of these catalyzers was implemented in 17 sulfur recovery tail gas processing facilities of 15 companies. As a result, Sinopec Jinling Petrochemical Company had outstanding application performances with a tail gas discharging rate lower than 77.9 mg/m3 and a total sulfur recovery of 99.97%.

Geochemical modelling of hydrogen gas migration in an unsaturated bentonite buffer

NARCIS (Netherlands)

Sedighi, M.; Thomas, H.R.; Al Masum, S.; Vardon, P.J.; Nicholson, D.; Chen, Q.

2014-01-01

This paper presents an investigation of the transport and fate of hydrogen gas through compacted bentonite buffer. Various geochemical reactions that may occur in the multiphase and multicomponent system of the unsaturated bentonite buffer are considered. A reactive gas transport model, developed

Experimental study on the natural gas dual fuel engine test and the higher the mixture ratio of hydrogen to natural gas

Energy Technology Data Exchange (ETDEWEB)

Kim, B.S.; Lee, Y.S.; Park, C.K. [Cheonnam University, Kwangju (Korea); Masahiro, S. [Kyoto University, Kyoto (Japan)

1999-05-28

One of the unsolved problems of the natural gas dual fuel engine is that there is too much exhaust of Total Hydrogen Carbon(THC) at a low equivalent mixture ratio. To fix it, a natural gas mixed with hydrogen was applied to engine test. The results showed that the higher the mixture ratio of hydrogen to natural gas, the higher the combustion efficiency. And when the amount of the intake air is reached to 90% of WOT, the combustion efficiency was promoted. But, like a case making the injection timing earlier, the equivalent mixture ratio for the nocking limit decreases and the produce of NOx increases. 5 refs., 9 figs., 1 tab.

Measurement of percent hydrogen in the mechanical vacuum pump gas stream during BWR startup

International Nuclear Information System (INIS)

Garcia, Susan E.; Odell, Andrew D.; Giannelli, Joseph F.

2012-09-01

All U.S BWRs use a Mechanical Vacuum Pump (MVP) to establish condenser vacuum during start-ups, normally from the initial heat-up to the point where sufficient reactor steam pressure and flow is available to place the Steam Jet Air Ejector (SJAE) and off-gas treatment system in service. MVP operation is restricted to <5% power and gas stream concentrations of <4% H 2 , the lower flammability limit (LFL) for hydrogen/air mixtures. For a particular plant startup prior to hydrogen injection for hydrogen water chemistry (HWC), the MVP %H 2 would depend on the air in-leakage rate, the H 2 gas generation rate from radiolysis and the gas/steam transport rate from the reactor vessel to the main condenser. The radiolysis rate at low power, which is not precisely known and has not been modeled for the BWR, is normally assumed to increase in proportion to thermal power. Two thirds of the radiolytic gas by volume would be H 2 and one third O 2 . The MVP is not equipped with %H 2 sampling and measurement capability, and many MVP systems include no flow measurement. No U.S plant or literature data on MVP %H 2 were found. The industry-first Early Hydrogen Water Chemistry (EHWC) demonstration at the Peach Bottom 3 nuclear power plant involved hydrogen gas injection into the reactor vessel during startup while the MVP was in service. To support the EHWC project, it was necessary to collect baseline MVP %H 2 data during a startup without hydrogen injection and to monitor MVP %H 2 during the startup with EHWC. The MVP system had no normal sample point, but included test taps in the suction and discharge piping. A sampling method and apparatus was invented (EPRI patent pending), designed, built and applied to obtain %H 2 measurements in the MVP gas stream. The apparatus allowed a gas sample stream to be taken from either the suction (vacuum) or discharge side of the MVP. The gas sample stream was preconditioned to remove moisture (the MVP uses water as a liquid compressant), flowed to

Studies on the separation of hydrogen isotopes and spin isomers by gas chromatography

International Nuclear Information System (INIS)

Pushpa, K.K.; Annaji Rao, K.

2000-08-01

Separation and analysis of mixture of hydrogen isotopes has gained considerable importance because of various applications needing different isotopes in lasers, nuclear reactions and tracer or labelled compounds. In the literature gas chromatographic methods are reported using columns packed with partly dehydrated or thoroughly dehydrated alumina/molecular sieve stationary phase at 77 deg K with helium, neon and even hydrogen or deuterium as carrier gas. In the present study an attempt is made to compare the chromatographic behaviour of these two stationary phases using virgin and Fe doped form in partly dehydrated and thoroughly dehydrated state, using helium, neon, hydrogen and deuterium as carrier gas. The results of this study show that helium or neon carrier gas behave similarly broad peaks with some tailing. Sharp symmetric peaks are obtained with hydrogen or deuterium carrier gas. This is attributed to large hold up capacity for H 2 or D 2 at 77 deg K in these materials as compared to helium or neon. Spin isomers of H 2 or D 2 are separated on Fe free stationary phases, though ortho H 2 and HD are not resolved. Using a combination of Fe doped short column and plain alumina column, both maintained in dehydrated form, the effect of Fe doping on thermal equilibrium of ortho/para forms at 77 deg K is clearly demonstrated. (author)

Hydrogen Gas from Serpentinite, Ophiolites and the Modern Ocean Floor as a Source of Green Energy

Science.gov (United States)

Coveney, R. M.

2008-12-01

Hydrogen gas is emitted by springs associated with serpentinites and extensive carbonate deposits in Oman, The Philippines, the USA and other continental locations. The hydrogen springs contain unusually alkaline fluids with pH values between 11 and 12.5. Other workers have described off-ridge submarine springs with comparably alkaline fluid compositions, serpentinite, abundant free hydrogen gas, and associated carbonate edifices such as Lost City on the Atlantis Massif 15 km west of the Mid-Atlantic Ridge (D.S. Kelley and associates, Science 2005). The association of hydrogen gas with ultramafites is a consistent one that has been attributed to a redox couple involving oxidation of divalent iron to the trivalent state during serpentinization, although other possibilities exist. Some of the hydrogen springs on land are widespread. For example in Oman dozens of alkaline springs (Neal and Stanger, EPSL 1983) can be found over thousands of sq km of outcropping ophiolite. While the deposits in Oman and the Philippines are well-known to much of the geochemical community, little interest seems to have been displayed toward either the ophiolitic occurrences or the submarine deposits for energy production. This may be a mistake as the showings because they could lead to an important source of green energy. Widespread skepticism currently exists about hydrogen as a primary energy source. It is commonly said that free hydrogen does not occur on earth and that it is therefore necessary to use other sources of energy to produce hydrogen, obviating the general environmental benefit. However the existence of numerous occurrences of hydrogen gas associated with ophiolites and submarine occurrences of hydrogen suggests the likelihood that natural hydrogen gas may be an important source of clean energy for modern society remaining to be tapped. Calculations in progress should establish whether or not this is likely to be the case.

Advanced IGCC/Hydrogen Gas Turbine Development

Energy Technology Data Exchange (ETDEWEB)

York, William [General Electric Company, Schenectady, NY (United States); Hughes, Michael [General Electric Company, Schenectady, NY (United States); Berry, Jonathan [General Electric Company, Schenectady, NY (United States); Russell, Tamara [General Electric Company, Schenectady, NY (United States); Lau, Y. C. [General Electric Company, Schenectady, NY (United States); Liu, Shan [General Electric Company, Schenectady, NY (United States); Arnett, Michael [General Electric Company, Schenectady, NY (United States); Peck, Arthur [General Electric Company, Schenectady, NY (United States); Tralshawala, Nilesh [General Electric Company, Schenectady, NY (United States); Weber, Joseph [General Electric Company, Schenectady, NY (United States); Benjamin, Marc [General Electric Company, Schenectady, NY (United States); Iduate, Michelle [General Electric Company, Schenectady, NY (United States); Kittleson, Jacob [General Electric Company, Schenectady, NY (United States); Garcia-Crespo, Andres [General Electric Company, Schenectady, NY (United States); Delvaux, John [General Electric Company, Schenectady, NY (United States); Casanova, Fernando [General Electric Company, Schenectady, NY (United States); Lacy, Ben [General Electric Company, Schenectady, NY (United States); Brzek, Brian [General Electric Company, Schenectady, NY (United States); Wolfe, Chris [General Electric Company, Schenectady, NY (United States); Palafox, Pepe [General Electric Company, Schenectady, NY (United States); Ding, Ben [General Electric Company, Schenectady, NY (United States); Badding, Bruce [General Electric Company, Schenectady, NY (United States); McDuffie, Dwayne [General Electric Company, Schenectady, NY (United States); Zemsky, Christine [General Electric Company, Schenectady, NY (United States)

2015-07-30

The objective of this program was to develop the technologies required for a fuel flexible (coal derived hydrogen or syngas) gas turbine for IGCC that met DOE turbine performance goals. The overall DOE Advanced Power System goal was to conduct the research and development (R&D) necessary to produce coal-based IGCC power systems with high efficiency, near-zero emissions, and competitive capital cost. To meet this goal, the DOE Fossil Energy Turbine Program had as an interim objective of 2 to 3 percentage points improvement in combined cycle (CC) efficiency. The final goal is 3 to 5 percentage points improvement in CC efficiency above the state of the art for CC turbines in IGCC applications at the time the program started. The efficiency goals were for NOx emissions of less than 2 ppm NOx (@15 % O2). As a result of the technologies developed under this program, the DOE goals were exceeded with a projected 8 point efficiency improvement. In addition, a new combustion technology was conceived of and developed to overcome the challenges of burning hydrogen and achieving the DOE’s NOx goal. This report also covers the developments under the ARRA-funded portion of the program that include gas turbine technology advancements for improvement in the efficiency, emissions, and cost performance of gas turbines for industrial applications with carbon capture and sequestration. Example applications could be cement plants, chemical plants, refineries, steel and aluminum plants, manufacturing facilities, etc. The DOE’s goal for more than 5 percentage point improvement in efficiency was met with cycle analyses performed for representative IGCC Steel Mill and IGCC Refinery applications. Technologies were developed in this program under the following areas: combustion, larger latter stage buckets, CMC and EBC, advanced materials and coatings, advanced configurations to reduce cooling, sealing and rotor purge flows, turbine aerodynamics, advanced sensors, advancements in first

Measurements of Gasification Characteristics of Coal and Char in CO2-Rich Gas Flow by TG-DTA

Directory of Open Access Journals (Sweden)

Zhigang Li

2013-01-01

Full Text Available Pyrolysis, combustion, and gasification properties of pulverized coal and char in CO2-rich gas flow were investigated by using gravimetric-differential thermal analysis (TG-DTA with changing O2%, heating temperature gradient, and flow rate of CO2-rich gases provided. Together with TG-DTA, flue gas generated from the heated coal, such as CO, CO2, and hydrocarbons (HCs, was analyzed simultaneously on the heating process. The optimum O2% in CO2-rich gas for combustion and gasification of coal or char was discussed by analyzing flue gas with changing O2 from 0 to 5%. The experimental results indicate that O2% has an especially large effect on carbon oxidation at temperature less than 1100°C, and lower O2 concentration promotes gasification reaction by producing CO gas over 1100°C in temperature. The TG-DTA results with gas analyses have presented basic reference data that show the effects of O2 concentration and heating rate on coal physical and chemical behaviors for the expected technologies on coal gasification in CO2-rich gas and oxygen combustion and underground coal gasification.

Hydrogen gettering the overpressure gas from highly radioactive liquids

International Nuclear Information System (INIS)

Riley, D.L.; Schicker, J.R.

1996-04-01

Remediation of current inventories of high-activity radioactive liquid waste (HALW) requires transportation of Type-B quantities of radioactive material, possibly up to several hundred liters. However, the only currently certified packaging is limited to quantities of 50 ml (0.01 gal) quantities of Type-B radioactive liquid. Efforts are under way to recertify the existing packaging to allow the shipment of up to 4 L (1.1 gal) of Type-B quantities of HALW, but significantly larger packaging could be needed in the future. Scoping studies and preliminary designs have identified the feasibility of retrofitting an insert into existing casks, allowing the transport of up to 380 L (100 gal) of HALW. However, the insert design and ultimate certification strategy depend heavily on the gas-generating attributes of the HALW. A non-vented containment vessel filled with HALW, in the absence of any gas-mitigation technologies, poses a deflagration threat and, therefore, gas generation, specifically hydrogen generation, must be reliably controlled during all phases of transportation. Two techniques are available to mitigate hydrogen accumulation: recombiners and getters. Getters have an advantage over recombiners in that oxides are not required to react with the hydrogen. A test plan was developed to evaluate three forms of getter material in the presence of both simulated HALW and the gases that are produced by the HALW. These tests demonstrated that getters can react with hydrogen in the presence of simulated waste and in the presence of several other gases generated by the HALW, such as nitrogen, ammonia, nitrous oxide, and carbon monoxide. Although the use of such a gettering system has been shown to be technically feasible, only a preliminary design for its use has been completed. No further development is planned until the requirement for bulk transport of Type-B quantities of HALW is more thoroughly defined

EUV tools: hydrogen gas purification and recovery strategies

Science.gov (United States)

Landoni, Cristian; Succi, Marco; Applegarth, Chuck; Riddle Vogt, Sarah

2015-03-01

The technological challenges that have been overcome to make extreme ultraviolet lithography (EUV) a reality have been enormous1. This vacuum driven technology poses significant purity challenges for the gases employed for purging and cleaning the scanner EUV chamber and source. Hydrogen, nitrogen, argon and ultra-high purity compressed dry air (UHPCDA) are the most common gases utilized at the scanner and source level. Purity requirements are tighter than for previous technology node tools. In addition, specifically for hydrogen, EUV tool users are facing not only gas purity challenges but also the need for safe disposal of the hydrogen at the tool outlet. Recovery, reuse or recycling strategies could mitigate the disposal process and reduce the overall tool cost of operation. This paper will review the types of purification technologies that are currently available to generate high purity hydrogen suitable for EUV applications. Advantages and disadvantages of each purification technology will be presented. Guidelines on how to select the most appropriate technology for each application and experimental conditions will be presented. A discussion of the most common approaches utilized at the facility level to operate EUV tools along with possible hydrogen recovery strategies will also be reported.

A fatigue initiation parameter for gas pipe steel submitted to hydrogen absorption

Energy Technology Data Exchange (ETDEWEB)

Capelle, J; Gilgert, J; Pluvinage, G [LaBPS - Ecole Nationale d' Ingenieurs de Metz et Universite Paul Verlaine Metz, Ile du Saulcy, 57045 Metz (France)

2010-01-15

Fatigue initiation resistance has been determined on API 5L X52 gas pipe steel. Tests have been performed on Roman Tile (RT) specimen and fatigue initiation was detected by acoustic emission. A comparison between specimens electrolytically charged with hydrogen and specimens without hydrogen absorption were made and it has been noted that fatigue initiation time is reduced of about 3 times when hydrogen embrittlement occurs. It has been proposed to use the concept of Notch Stress Intensity Factor as parameter to describe the fatigue initiation process. Due to the fact that hydrogen is localised in area with high hydrostatic pressure, definitions of local effective stress and distance have been modified when hydrogen is absorbed. This modification can be explained by existence of a ductile-brittle transition with hydrogen concentration. The fatigue initiation resistance curve allows that to determine a threshold for large number of cycles of fatigue non initiation. This parameter introduced in a Failure Assessment Diagram (FAD) provides supplementary information about defect nocivity in gas pipes: a non-critical defect can be detected as dormant or not dormant defect i.e., as non propagating defect. (author)

Hydrogen-Enhanced Natural Gas Vehicle Program

Energy Technology Data Exchange (ETDEWEB)

Hyde, Dan; Collier, Kirk

2009-01-22

The project objective is to demonstrate the viability of HCNG fuel (30 to 50% hydrogen by volume and the remainder natural gas) to reduce emissions from light-duty on-road vehicles with no loss in performance or efficiency. The City of Las Vegas has an interest in alternative fuels and already has an existing hydrogen refueling station. Collier Technologies Inc (CT) supplied the latest design retrofit kits capable of converting nine compressed natural gas (CNG) fueled, light-duty vehicles powered by the Ford 5.4L Triton engine. CT installed the kits on the first two vehicles in Las Vegas, trained personnel at the City of Las Vegas (the City) to perform the additional seven retrofits, and developed materials for allowing other entities to perform these retrofits as well. These vehicles were used in normal service by the City while driver impressions, reliability, fuel efficiency and emissions were documented for a minimum of one year after conversion. This project has shown the efficacy of operating vehicles originally designed to operate on compressed natural gas with HCNG fuel incorporating large quantities of exhaust gas recirculation (EGR). There were no safety issues experienced with these vehicles. The only maintenance issue in the project was some rough idling due to problems with the EGR valve and piping parts. Once the rough idling was corrected no further maintenance issues with these vehicles were experienced. Fuel economy data showed no significant changes after conversion even with the added power provided by the superchargers that were part of the conversions. Driver feedback for the conversions was very favorable. The additional power provided by the HCNG vehicles was greatly appreciated, especially in traffic. The drivability of the HCNG vehicles was considered to be superior by the drivers. Most of the converted vehicles showed zero oxides of nitrogen throughout the life of the project using the State of Nevada emissions station.

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

Energy Technology Data Exchange (ETDEWEB)

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

2018-01-01

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

Oral intake of hydrogen-rich water ameliorated chlorpyrifos-induced neurotoxicity in rats

Energy Technology Data Exchange (ETDEWEB)

Wang, Tingting; Zhao, Ling; Liu, Mengyu; Xie, Fei; Ma, Xuemei, E-mail: xmma@bjut.edu.cn; Zhao, Pengxiang; Liu, Yunqi; Li, Jiala; Wang, Minglian; Yang, Zhaona; Zhang, Yutong

2014-10-01

Chronic exposure to low-levels of organophosphate (OP) compounds, such as chlorpyrifos (CPF), induces oxidative stress and could be related to neurological disorders. Hydrogen has been identified as a novel antioxidant which could selectively scavenge hydroxyl radicals. We explore whether intake of hydrogen-rich water (HRW) can protect Wistar rats from CPF-induced neurotoxicity. Rats were gavaged daily with 6.75 mg/kg body weight (1/20 LD{sub 50}) of CPF and given HRW by oral intake. Nissl staining and electron microscopy results indicated that HRW intake had protective effects on the CPF-induced damage of hippocampal neurons and neuronal mitochondria. Immunostaining results showed that the increased glial fibrillary acidic protein (GFAP) expression in astrocytes induced by CPF exposure can be ameliorated by HRW intake. Moreover, HRW intake also attenuated CPF-induced oxidative stress as evidenced by enhanced level of MDA, accompanied by an increase in GSH level and SOD and CAT activity. Acetylcholinesterase (AChE) activity tests showed significant decrease in brain AChE activity after CPF exposure, and this effect can be ameliorated by HRW intake. An in vitro study demonstrated that AChE activity was more intense in HRW than in normal water with or without chlorpyrifos-oxon (CPO), the metabolically-activated form of CPF. These observations suggest that HRW intake can protect rats from CPF-induced neurotoxicity, and the protective effects of hydrogen may be mediated by regulating the oxidant and antioxidant status of rats. Furthermore, this work defines a novel mechanism of biological activity of hydrogen by directly increasing the AChE activity. - Highlights: • Hydrogen molecules protect rats from CPF-induced damage of hippocampal neurons. • The increased GFAP expression induced by CPF can also be ameliorated by hydrogen. • Hydrogen molecules attenuated the increase in CPF-induced oxidative stress. • Hydrogen molecules attenuated AChE inhibition in vivo

Oral intake of hydrogen-rich water ameliorated chlorpyrifos-induced neurotoxicity in rats

International Nuclear Information System (INIS)

Wang, Tingting; Zhao, Ling; Liu, Mengyu; Xie, Fei; Ma, Xuemei; Zhao, Pengxiang; Liu, Yunqi; Li, Jiala; Wang, Minglian; Yang, Zhaona; Zhang, Yutong

2014-01-01

Chronic exposure to low-levels of organophosphate (OP) compounds, such as chlorpyrifos (CPF), induces oxidative stress and could be related to neurological disorders. Hydrogen has been identified as a novel antioxidant which could selectively scavenge hydroxyl radicals. We explore whether intake of hydrogen-rich water (HRW) can protect Wistar rats from CPF-induced neurotoxicity. Rats were gavaged daily with 6.75 mg/kg body weight (1/20 LD 50 ) of CPF and given HRW by oral intake. Nissl staining and electron microscopy results indicated that HRW intake had protective effects on the CPF-induced damage of hippocampal neurons and neuronal mitochondria. Immunostaining results showed that the increased glial fibrillary acidic protein (GFAP) expression in astrocytes induced by CPF exposure can be ameliorated by HRW intake. Moreover, HRW intake also attenuated CPF-induced oxidative stress as evidenced by enhanced level of MDA, accompanied by an increase in GSH level and SOD and CAT activity. Acetylcholinesterase (AChE) activity tests showed significant decrease in brain AChE activity after CPF exposure, and this effect can be ameliorated by HRW intake. An in vitro study demonstrated that AChE activity was more intense in HRW than in normal water with or without chlorpyrifos-oxon (CPO), the metabolically-activated form of CPF. These observations suggest that HRW intake can protect rats from CPF-induced neurotoxicity, and the protective effects of hydrogen may be mediated by regulating the oxidant and antioxidant status of rats. Furthermore, this work defines a novel mechanism of biological activity of hydrogen by directly increasing the AChE activity. - Highlights: • Hydrogen molecules protect rats from CPF-induced damage of hippocampal neurons. • The increased GFAP expression induced by CPF can also be ameliorated by hydrogen. • Hydrogen molecules attenuated the increase in CPF-induced oxidative stress. • Hydrogen molecules attenuated AChE inhibition in vivo and in

Hydrogen dissociation in the deposition of GaN films with ECR-PECVD process

Science.gov (United States)

Fu, S. L.; Wang, C. A.; Ding, L. C.; Qin, Y. X.

2018-05-01

The hydrogen dissociation and its effect on the GaN film growth in the ECR-PECVD process are investigated in this paper. We use N2 and trimethylgallium (TMG) as N and Ga sources respectively in the ECR- PECVD process. The results show that the rate of hydrogen dissociation increases with the microwave power and it becomes higher at high microwave power (> 500 W). However, this population increase of the H species dissociated from the TMG gas in ECR plasma is not enough to change the growth condition from Ga-rich to N-rich.

Radioactive gas and hydrogen removal after a LOCE at the LOFT Facility

International Nuclear Information System (INIS)

McCormick-Barger, J.W.; Sumpter, K.C.

1979-01-01

The use of a silver-zeolite halogen adsorber placed in series with a hydrogen catalytic recombiner and a cryogenic noble gas adsorber assembly constitutes a waste gas processing system (WGPS) capable of handling hydrogen and fission product gases following a Loss-of-Coolant Experiment (LOCE). This paper describes: the types and quantities of gases expected to be found at the facility after a failed-fuel LOCE; the purpose of the WGPS; and the general configuration and expected decontamination factors associated with the LOFT WGPS

Performance of a hydrogen/deuterium polarized gas target in a storage ring

NARCIS (Netherlands)

van Buuren, L.D.; Szczerba, D.; van den Brand, J.F.J.; Bulten, H.J.; Klous, S.; Mul, F.A.; Poolman, H.R.; Simani, M.C.

2001-01-01

The performance of a hydrogen/deuterium polarized gas target in a storage ring is presented. The target setup consisted of an atomic beam source, a cryogenic storage cell and a Breit-Rabi polarimeter. High frequency transition units were constructed to produce vector polarized hydrogen and

Volatile element trends in gas-rich meteorites

Energy Technology Data Exchange (ETDEWEB)

Bart, G; Lipschutz, M E [Purdue Univ., Lafayette, IN (USA). Dept. of Chemistry

1979-09-01

Study of 10 volatile elements (and non-volatile Co) in co-existing light and dark portions of 5 gas-rich chondrites indicates patterns of distinct but non-uniform enrichment of volatile elements. Only Cs is enriched in all samples; Bi and Tl enrichments covary. The observed enrichments are inconsistent with prior suggestions of admixture of C1 or C2 chondritic matter, whether pristine or partly devolatilized, but suggest that both light and dark portions of each chondrite represents a compositionally more extended sampling of parental nebular material than hitherto known.

Utilization of hydrogen gas production for electricity generation in ...

African Journals Online (AJOL)

Utilization of hydrogen gas production for electricity generation in fuel cell by Enterobacter aerogenes ADH 43 with many kinds of carbon sources in batch stirred tank reactor. MA Rachman, LD Eniya, Y Liasari, MM Nasef, A Ahmad, H Saidi ...

Role of sodium hydroxide in the production of hydrogen gas from the hydrothermal gasification of biomass

Energy Technology Data Exchange (ETDEWEB)

Onwudili, Jude A.; Williams, Paul T. [Energy and Resources Research Institute, University of Leeds, Leeds, LS2 9JT (United Kingdom)

2009-07-15

The role of sodium hydroxide as a promoter of hydrogen gas production during the hydrothermal gasification of glucose and other biomass samples has been investigated. Experiments were carried out in a batch reactor with glucose and also in the presence of the alkali from 200 C, 2 MPa to 450 C, 34 MPa at constant water loading. Without sodium hydroxide, glucose decomposed to produce mainly carbon dioxide, water, char and tar. Furfural, its derivatives and reaction products dominated the ethyl acetate extract of the water (organic fraction) at lower reaction conditions. This indicated that the dehydration of glucose to yield these products was unfavourable to hydrogen gas production. In the presence of sodium hydroxide however, glucose initially decomposed to form mostly alkylated and hydroxylated carbonyl compounds, whose further decomposition yielded hydrogen gas. It was observed that at 350 C, 21.5 MPa, half of the optimum hydrogen gas yield had formed and at 450 C, 34 MPa, more than 80 volume percent of the gaseous effluent was hydrogen gas, while the balance was hydrocarbon gases, mostly methane ({>=}10 volume percent). Other biomass samples were also comparably reacted at the optimum conditions observed for glucose. The rate of hydrogen production for the biomass samples was in the following order; glucose > cellulose, starch, rice straw > potato > rice husk. (author)

The effect of hydrogen enrichment towards the flammability limits of natural gas in conventional combustion

International Nuclear Information System (INIS)

Izirwan Izhab; Nur Syuhada Mohd Shokri; Nurul Saadah Sulaiman; Mohd Zulkifli Mohamad Noor; Siti Zubaidah Sulaiman; Rosmawati Naim; Norida Ridzuan, Mohd Masri Razak; Abdul Halim Abdul Razik; Zulkafli Hassan

2010-01-01

The use of hydrogenated fuels shows a considerable promise for the applications in gas turbines and internal combustion engines. The aims of this study are to determine the flammability limits of natural gas/ air mixtures and to investigate the effect of hydrogen enrichment on the flammability limits of natural gas/ air mixtures up to 60 vol % of hydrogen/fuel volume ratio at atmospheric pressure and ambient temperature. The experiments were performed in a 20 L closed explosion vessel where the mixtures were ignited by using a spark permanent wire that was placed at the centre of the vessel. The pressure-time variations during explosions of natural gas/ air mixtures in an explosion vessel were recorded. Moreover, the explosion pressure data is used to determine the flammability limits that flame propagation is considered to occur if explosion pressure is greater than 0.1 bar. Therefore, in this study, the results show that the range of flammability limits are from 6 vol % to 15 vol % and by the addition of hydrogen in natural gas proved to extend the initial lower flammability limit of 6 vol % to 2 vol % of methane. (author)

Gas--liquid equilibria in mixtures of hydrogen and thianaphthene

Energy Technology Data Exchange (ETDEWEB)

Sebastian, H M; Simnick, J J; Lin, H M; Chao, K C

1978-12-01

Gas--liquid equilibrium conditions in binary mixtures of hydrogen and thianaphthene were experimentally determined at temperature of 190 to 430/sup 0/C and pressures to 250 atm in a flow apparatus. The same apparatus was also employed to measure the vapor pressure of thianaphthene. Comparisons of the new mixture data with Chao--Seader and Grayson--Streed correlations show that both correlations predict the thianaphthene equilibrium ratios well but are in error by up to about 45 and 35% respectively for K-values of hydrogen. 4 figures, 2 tables.

Hydrogen Gas Sensing Characteristics of Nanostructured NiO Thin Films Synthesized by SILAR Method

Science.gov (United States)

Karaduman, Irmak; Çorlu, Tugba; Yıldırım, M. Ali; Ateş, Aytunç; Acar, Selim

2017-07-01

Nanostructured NiO thin films have been synthesized by a facile, low-cost successive ionic layer adsorption and reaction (SILAR) method, and the effects of the film thickness on their hydrogen gas sensing properties investigated. The samples were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD) analysis, and energy-dispersive x-ray analysis. The XRD results revealed that the crystallinity improved with increasing thickness, exhibiting polycrystalline structure. SEM studies showed that all the films covered the glass substrate well. According to optical absorption measurements, the optical bandgap decreased with increasing film thickness. The gas sensing properties of the nanostructured NiO thin films were studied as a function of operating temperature and gas concentration. The samples showed good sensing performance of H2 gas with high response. The maximum response was 75% at operating temperature of 200°C for hydrogen gas concentration of 40 ppm. These results demonstrate that nanostructured NiO thin films synthesized by the SILAR method have potential for application in hydrogen detection.

Start up system for hydrogen generator used with an internal combustion engine

Science.gov (United States)

Houseman, J.; Cerini, D. J. (Inventor)

1977-01-01

A hydrogen generator provides hydrogen rich product gases which are mixed with the fuel being supplied to an internal combustion engine for the purpose of enabling a very lean mixture of that fuel to be used, whereby nitrous oxides emitted by the engine are minimized. The hydrogen generator contains a catalyst which must be heated to a pre-determined temperature before it can react properly. To simplify the process of heating up the catalyst at start-up time, either some of the energy produced by the engine such as engine exhaust gas, or electrical energy produced by the engine, or the engine exhaust gas may be used to heat up air which is then used to heat the catalyst.

Coal pyrolysis under synthesis gas, hydrogen and nitrogen

Energy Technology Data Exchange (ETDEWEB)

Ariunaa, A.; Li Bao-Qing; Li Wen; Purevsuren, B. (and others) [Chinese Academy of Sciences, Taiyuan (China)

2007-02-15

Chinese Xundian, Mongolian Shiveeovoo lignites and Khoot oil shale are pyrolyzed under synthesis gas (SG) at temperature range from 400 to 800{sup o}C for lignite and from 300 to 600{sup o}C for oil shale with heating rate of 10{sup o}C/min in a fixed bed reactor. The results were compared with those obtained by pyrolysis under hydrogen and nitrogen. The results showed that unlike pyrolysis at high pressure, there are only slight different in the yields of char and tar among pyrolyses under various gases at room pressure for lignite, while higher liquid yield with lower yields of char and gas was obtained in pyrolysis of oil shale under SG and H{sub 2} than under N{sub 2}. It is found that the pyrite S can be easily removed to partially convert to organic S under various gaseous atmosphere and the total sulfur removal for oil shale is much less than lignite, which might be related to its high ash content. The higher total sulfur removal and less organic S content in the presence of SG in comparison with those under N{sub 2} and even under H{sub 2} in pyrolysis of Xundian lignite might result from the action of CO in SG. However, CO does not show its function in pyrolysis of Khoot oil shale, which might also be related to the high ash content. The results reported show the possibility of using synthesis gas instead of pure hydrogen as the reactive gas for coal hydropyrolysis. 11 refs., 4 figs., 6 tabs.

Effectiveness of oxygen enriched hydrogen-HHO gas addition on DI diesel engine performance, emission and combustion characteristics

Directory of Open Access Journals (Sweden)

Premkartikkumar S.R.

2014-01-01

Full Text Available Nowadays, more researches focus on protecting the environment. Present investigation concern with the effectiveness of Oxygen Enriched hydrogen- HHO gas addition on performance, emission and combustion characteristics of a DI diesel engine. Here the Oxygen Enriched hydrogen-HHO gas was produced by the process of water electrolysis. When potential difference is applied across the anode and cathode electrodes of the electrolyzer, water is transmuted into Oxygen Enriched hydrogen-HHO gas. The produced gas was aspirated into the cylinder along with intake air at the flow rates of 1 lpm and 3.3 lpm. The results show that when Oxygen Enriched hydrogen-HHO gas was inducted, the brake thermal efficiency of the engine increased by 11.06%, Carbon monoxide decreased by 15.38%, Unburned hydrocarbon decreased by 18.18%, Carbon dioxide increased by 6.06%, however, the NOX emission increased by 11.19%.

Hydrogen-rich saline attenuates anxiety-like behaviors in morphine-withdrawn mice.

Science.gov (United States)

Wen, Di; Zhao, Peng; Hui, Rongji; Wang, Jian; Shen, Qianchao; Gong, Miao; Guo, Hongyan; Cong, Bin; Ma, Chunling

2017-05-15

Hydrogen therapy is a new medical approach for a wide range of diseases. The effects of hydrogen on central nervous system-related diseases have recently become increasingly appreciated, but little is known about whether hydrogen affects the morphine withdrawal process. This study aims to investigate the potential effects of hydrogen-rich saline (HRS) administration on naloxone-precipitated withdrawal symptoms and morphine withdrawal-induced anxiety-like behaviors. Mice received gradually increasing doses (25-100 mg/kg, i.p.) of morphine over 3 days. In the naloxone-precipitated withdrawal procedure, the mice were treated with three HRS (20 μg/kg, i.p.) injections, and naloxone (1 mg/kg, i.p.) was given 30 min after HRS administration. Body weight, jumping behavior and wet-dog shakes were immediately assessed. In the spontaneous withdrawal procedure, the mice were treated with HRS (20 μg/kg, i.p.) every 8-h. Mice underwent naloxone-precipitated or spontaneous withdrawal were tested for anxiety-like behaviors in the elevated plus-maze (EPM) and light/dark box (L/D box) paradigm, respectively. In addition, the levels of plasma corticosterone were measured. We found that HRS administration significantly reduced body weight loss, jumping behavior and wet-dog shakes in mice underwent naloxone-precipitated withdrawal, and attenuated anxiety-like behaviors in the EPM and L/D box tests after naloxone-precipitated withdrawal or a 2-day spontaneous withdrawal period. Hypo-activity or motor impairment after HRS administration was not observed in the locomotion tests. Furthermore, HRS administration significantly decreased the levels of corticosterone in morphine-withdrawn mice. These are the first findings to indicate that hydrogen might ameliorate withdrawal symptoms and exert an anxiolytic-like effect in morphine-withdrawal mice. Copyright © 2017 Elsevier Ltd. All rights reserved.

Hydrogen Gas as a Fuel in Direct Injection Diesel Engine

Science.gov (United States)

Dhanasekaran, Chinnathambi; Mohankumar, Gabriael

2016-04-01

Hydrogen is expected to be one of the most important fuels in the near future for solving the problem caused by the greenhouse gases, for protecting environment and saving conventional fuels. In this study, a dual fuel engine of hydrogen and diesel was investigated. Hydrogen was conceded through the intake port, and simultaneously air and diesel was pervaded into the cylinder. Using electronic gas injector and electronic control unit, the injection timing and duration varied. In this investigation, a single cylinder, KIRLOSKAR AV1, DI Diesel engine was used. Hydrogen injection timing was fixed at TDC and injection duration was timed for 30°, 60°, and 90° crank angles. The injection timing of diesel was fixed at 23° BTDC. When hydrogen is mixed with inlet air, emanation of HC, CO and CO2 decreased without any emission (exhaustion) of smoke while increasing the brake thermal efficiency.

Visualization of hydrogen gas evolution during deformation and fracture in SCM 440 steel with different tempering conditions

International Nuclear Information System (INIS)

Horikawa, Keitaro; Ando, Nobuaki; Kobayashi, Hidetoshi; Urushihara, Wataru

2012-01-01

Highlights: ► We visualize emission sites of hydrogen atoms on the microstructures during deformation. ► Hydrogen atoms are emitted from slip lines and inclusions when deformed. ► We show the sequence of hydrogen gas evolution during deformation. ► Hydrogen evolution amount will increase if the steels with high strength are tested. - Abstract: In the present study, the hydrogen gas evolution behavior was investigated in SCM 440 steel by using a hydrogen microprint technique (HMT) and a testing machine equipped with a quadrupole mass spectrometer (QMS) in a ultrahigh vacuum (UHV) atmosphere. SCM 440 steels prepared by varying the tempering temperature over the range 200–700 °C were evaluated in order to elucidate the relationship between the hydrogen gas evolution and the tempered microstructures in the deformation. Cathodic hydrogen charging was carried out with a current density of 100 A/m 2 for 1 h at room temperature. For comparison, a tensile specimen was prepared without hydrogen charging. The HMT showed that silver particles, which are indicative of the hydrogen emission sites, were present mainly in the matrix as well as on the slip lines after the deformation. It is believed that the silver particles on the slip lines represent the effect of hydrogen transportation due to mobile dislocations. In addition, accumulation of silver particles around non-metallic inclusions such as Al 2 O 3 was also identified. This tendency was observed for different tempering conditions. From the relationship between the stress–strain curves and the hydrogen evolution, determined by using QMS under a UHV atmosphere, it was found that the hydrogen gas evolution behavior varied with the deformation stage.

Stability of MOF-5 in a hydrogen gas environment containing fueling station impurities

DEFF Research Database (Denmark)

Ming, Yang; Purewal, Justin; Yang, Jun

2016-01-01

, HCl, H2O, CO, CO2, CH4, O2, N2, and He) to pure hydrogen gas. Subsequently, MOF-5 was exposed to these mixtures over hundreds of adsorption/desorption pressure-swing cycles and for extended periods of static exposure. The impact of exposure was assessed by periodically measuring the hydrogen storage...... of these contaminants on MOFs is mostly unknown. In the present study MOF-5 is adopted as a prototypical moisture-sensitive hydrogen storage material. Five “impure” gas mixtures were prepared by introducing low-to-moderate levels (i.e., up to ∼200 times greater than the J2719 limit) of selected contaminants (NH3, H2S...

Carbon dioxide emission in hydrogen production technology from coke oven gas with life cycle approach

Directory of Open Access Journals (Sweden)

Burmistrz Piotr

2016-01-01

Full Text Available The analysis of Carbon Footprint (CF for technology of hydrogen production from cleaned coke oven gas was performed. On the basis of real data and simulation calculations of the production process of hydrogen from coke gas, emission indicators of carbon dioxide (CF were calculated. These indicators are associated with net production of electricity and thermal energy and direct emission of carbon dioxide throughout a whole product life cycle. Product life cycle includes: coal extraction and its transportation to a coking plant, the process of coking coal, purification and reforming of coke oven gas, carbon capture and storage. The values were related to 1 Mg of coking blend and to 1 Mg of the hydrogen produced. The calculation is based on the configuration of hydrogen production from coke oven gas for coking technology available on a commercial scale that uses a technology of coke dry quenching (CDQ. The calculations were made using ChemCAD v.6.0.2 simulator for a steady state of technological process. The analysis of carbon footprint was conducted in accordance with the Life Cycle Assessment (LCA.

The self limiting effect of hydrogen cluster in gas jet under liquid nitrogen temperature

International Nuclear Information System (INIS)

Han Jifeng; Yang Chaowen; Miao Jingwei; Fu Pengtao; Luo Xiaobing; Shi Miangong

2010-01-01

The generation of hydrogen clusters in gas jet is tested using the Rayleigh scattering method under liquid nitrogen temperature of 79 K. The self limiting effect of hydrogen cluster is studied and it is found that the cluster formation is greatly affected by the number of expanded molecules. The well designed liquid nitrogen cold trap ensured that the hydrogen cluster would keep maximum size for maximum 15 ms during one gas jet. The scattered light intensity exhibits a power scaling on the backing pressure ranging from 5 to 48 bar with the power value of 4.1.

Potential for greenhouse gas emission reductions using surplus electricity in hydrogen, methane and methanol production via electrolysis

International Nuclear Information System (INIS)

Uusitalo, Ville; Väisänen, Sanni; Inkeri, Eero; Soukka, Risto

2017-01-01

Highlights: • Greenhouse gas emission reductions using power-to-x processes are studied using life cycle assessment. • Surplus electricity use led to greenhouse gas emission reductions in all studied cases. • Highest reductions can be achieved by using hydrogen to replace fossil based hydrogen. • High reductions are also achieved when fossil transportation fuels are replaced. - Abstract: Using a life cycle perspective, potentials for greenhouse gas emission reductions using various power-to-x processes via electrolysis have been compared. Because of increasing renewable electricity production, occasionally surplus renewable electricity is produced, which leads to situations where the price of electricity approach zero. This surplus electricity can be used in hydrogen, methane and methanol production via electrolysis and other additional processes. Life cycle assessments have been utilized to compare these options in terms of greenhouse gas emission reductions. All of the power-to-x options studied lead to greenhouse gas emission reductions as compared to conventional production processes based on fossil fuels. The highest greenhouse gas emission reductions can be gained when hydrogen from steam reforming is replaced by hydrogen from the power-to-x process. High greenhouse gas emission reductions can also be achieved when power-to-x products are utilized as an energy source for transportation, replacing fossil transportation fuels. A third option with high greenhouse gas emission reduction potential is methane production, storing and electricity conversion in gas engines during peak consumption hours. It is concluded that the power-to-x processes provide a good potential solution for reducing greenhouse gas emissions in various sectors.

Impact of pH on hydrogen oxidizing redox processes in aquifers due to gas intrusions

Science.gov (United States)

Metzgen, Adrian; Berta, Marton; Dethlefsen, Frank; Ebert, Markus; Dahmke, Andreas

2017-04-01

Hydrogen production from excess energy and its storage can help increasing the efficiency of solar and wind in the energy mix. Therefore, hydrogen needs large-scale intermediate storage independent of the intended later use as hydrogen gas or as reactant to produce methane in the Sabatier process. A possible storage solution is using the geological subsurface such as caverns built in salt deposits or aquifers that are not used for drinking water production. However, underground storage of hydrogen gas potentially leads to accidental gas leakages into near-surface potable aquifers triggering subsequent geochemical processes. These leakages pose potential risks that are currently not sufficiently understood. To close this gap in knowledge, a high-pressure laboratory column system was used to simulate a hydrogen gas intrusion into a shallow aquifer. Water and sediment were gained from a sandy Pleistocene aquifer near Neumünster, Germany. In the first stage of the experiment, 100% hydrogen gas was used to simulate dissolved hydrogen concentrations between 800 and 4000 µM by varying pH2 between 2 and 15 bars. pH values rose to between 7.9 and 10.4, partly due to stripping CO2 from the groundwater used during H2 gas addition. In a second stage, the pH was regulated in a range of 6.7 to 7.9 by using a gas mixture of 99% H2 and 1% CO2 at 5 bars of total gas pressure. Observed processes included hydrogen oxidation, sulfate reduction, acetogenesis, formate production, and methanogenesis, which were independent of the hydrogen concentration. Hydrogen oxidation and sulfate reduction showed zeroth order reaction rates and rate constants (106 to 412 µM/h and 12 to 33 µM/h, respectively) in the pH range between 8 and 10. At pH levels between 7 and 8, both reactions started out faster near the column's inflow but then seemed limited towards the columns outflow, suggesting the dependence of sulfate reduction on the pH-value. Acetogenesis dominated the pH range between 8 and 10

XUV-exposed, non-hydrostatic hydrogen-rich upper atmospheres of terrestrial planets. Part II: hydrogen coronae and ion escape.

Science.gov (United States)

Kislyakova, Kristina G; Lammer, Helmut; Holmström, Mats; Panchenko, Mykhaylo; Odert, Petra; Erkaev, Nikolai V; Leitzinger, Martin; Khodachenko, Maxim L; Kulikov, Yuri N; Güdel, Manuel; Hanslmeier, Arnold

2013-11-01

We studied the interactions between the stellar wind plasma flow of a typical M star, such as GJ 436, and the hydrogen-rich upper atmosphere of an Earth-like planet and a "super-Earth" with a radius of 2 R(Earth) and a mass of 10 M(Earth), located within the habitable zone at ∼0.24 AU. We investigated the formation of extended atomic hydrogen coronae under the influences of the stellar XUV flux (soft X-rays and EUV), stellar wind density and velocity, shape of a planetary obstacle (e.g., magnetosphere, ionopause), and the loss of planetary pickup ions on the evolution of hydrogen-dominated upper atmospheres. Stellar XUV fluxes that are 1, 10, 50, and 100 times higher compared to that of the present-day Sun were considered, and the formation of high-energy neutral hydrogen clouds around the planets due to the charge-exchange reaction under various stellar conditions was modeled. Charge-exchange between stellar wind protons with planetary hydrogen atoms, and photoionization, lead to the production of initially cold ions of planetary origin. We found that the ion production rates for the studied planets can vary over a wide range, from ∼1.0×10²⁵ s⁻¹ to ∼5.3×10³⁰ s⁻¹, depending on the stellar wind conditions and the assumed XUV exposure of the upper atmosphere. Our findings indicate that most likely the majority of these planetary ions are picked up by the stellar wind and lost from the planet. Finally, we estimated the long-time nonthermal ion pickup escape for the studied planets and compared them with the thermal escape. According to our estimates, nonthermal escape of picked-up ionized hydrogen atoms over a planet's lifetime within the habitable zone of an M dwarf varies between ∼0.4 Earth ocean equivalent amounts of hydrogen (EO(H)) to <3 EO(H) and usually is several times smaller in comparison to the thermal atmospheric escape rates.

XUV-Exposed, Non-Hydrostatic Hydrogen-Rich Upper Atmospheres of Terrestrial Planets. Part II: Hydrogen Coronae and Ion Escape

Science.gov (United States)

Lammer, Helmut; Holmström, Mats; Panchenko, Mykhaylo; Odert, Petra; Erkaev, Nikolai V.; Leitzinger, Martin; Khodachenko, Maxim L.; Kulikov, Yuri N.; Güdel, Manuel; Hanslmeier, Arnold

2013-01-01

Abstract We studied the interactions between the stellar wind plasma flow of a typical M star, such as GJ 436, and the hydrogen-rich upper atmosphere of an Earth-like planet and a “super-Earth” with a radius of 2 REarth and a mass of 10 MEarth, located within the habitable zone at ∼0.24 AU. We investigated the formation of extended atomic hydrogen coronae under the influences of the stellar XUV flux (soft X-rays and EUV), stellar wind density and velocity, shape of a planetary obstacle (e.g., magnetosphere, ionopause), and the loss of planetary pickup ions on the evolution of hydrogen-dominated upper atmospheres. Stellar XUV fluxes that are 1, 10, 50, and 100 times higher compared to that of the present-day Sun were considered, and the formation of high-energy neutral hydrogen clouds around the planets due to the charge-exchange reaction under various stellar conditions was modeled. Charge-exchange between stellar wind protons with planetary hydrogen atoms, and photoionization, lead to the production of initially cold ions of planetary origin. We found that the ion production rates for the studied planets can vary over a wide range, from ∼1.0×1025 s−1 to ∼5.3×1030 s−1, depending on the stellar wind conditions and the assumed XUV exposure of the upper atmosphere. Our findings indicate that most likely the majority of these planetary ions are picked up by the stellar wind and lost from the planet. Finally, we estimated the long-time nonthermal ion pickup escape for the studied planets and compared them with the thermal escape. According to our estimates, nonthermal escape of picked-up ionized hydrogen atoms over a planet's lifetime within the habitable zone of an M dwarf varies between ∼0.4 Earth ocean equivalent amounts of hydrogen (EOH) to stars—Early atmospheres—Earth-like exoplanets—Energetic neutral atoms—Ion escape—Habitability. Astrobiology 13, 1030–1048. PMID:24283926

Comparison of hydrogen gas embrittlement of austenitic and ferritic stainless steels

Science.gov (United States)

Perng, T. P.; Altstetter, C. J.

1987-01-01

Hydrogen-induced slow crack growth (SCG) was compared in austenitic and ferritic stainless steels at 0 to 125 °Cand 11 to 216 kPa of hydrogen gas. No SCG was observed for AISI 310, while AISI 301 was more susceptible to hydrogen embrittlement and had higher cracking velocity than AL 29-4-2 under the same test conditions. The kinetics of crack propagation was modeled in terms of the hydrogen transport in these alloys. This is a function of temperature, microstructure, and stress state in the embrittlement region. The relatively high cracking velocity of AISI 301 was shown to be controlled by the fast transport of hydrogen through the stress-induced α' martensite at the crack tip and low escape rate of hydrogen through the γ phase in the surrounding region. Faster accumulation rates of hydrogen in the embrittlement region were expected for AISI 301, which led to higher cracking velocities. The mechanism of hydrogen-induced SCG was discussed based upon the concept of hydrogen-enhanced plasticity.

Appraisal of bio-hydrogen production schemes

International Nuclear Information System (INIS)

Bent Sorensen

2006-01-01

Work is ongoing on several schemes of biological hydrogen production. At one end is the genetic modification of biological systems (such as algae or cyanobacteria) to produce hydrogen from photosynthesis, instead of the energy-rich compounds (such as NADPH 2 ) normally constituting the endpoint of the transformations through the photo-systems. A second route is to collect and use the biomass produced by normal plant growth processes in a separate step that produces hydrogen. This may be done similar to biogas production by fermentation, where the endpoint is methane (plus CO 2 and minor constituents). Hydrogen could be the outcome of a secondary process starting from methane, involving any of the conventional methods of hydrogen production from natural gas. An alternative to fermentation is gasification of the biomass, followed by a shift-reaction leading to hydrogen. I compare advantages and disadvantages of these three routes, notably factors such as system efficiency, cost and environmental impacts, and also compare them to liquid biofuels. (author)

Extraction of deuterium from D-rich process condensate of ammonia plants

Energy Technology Data Exchange (ETDEWEB)

Haldar, T K; Kumar, Manoj; Ramamurty, C B [Heavy Water Board, Department of Atomic Energy, Mumbai (India)

1994-06-01

Heavy water plants based on ammonia-hydrogen exchange process receives feed synthesis gas from the adjacent fertilizer plants. The production capacity of such heavy water plants is directly proportional to the deuterium-content in feed synthesis gas. The chemical process involved in gas generation section of the fertilizer plant includes catalytic steam-reforming of natural gas/naphtha/fuel oil followed by shift conversion, alternatively coal classification followed by shift conversion. Effective extraction of deuterium from the deuterium-rich process condensate can boost the production capacity of heavy water plants considerably. This paper discusses various possible methods to achieve this objective. (author). 5 refs., 1 fig., 1 tab.

Exploring N-Rich Phases in Li(x)N(y) Clusters for Hydrogen Storage at Nanoscale.

Science.gov (United States)

Bhattacharya, Amrita; Bhattacharya, Saswata

2015-09-17

We have performed cascade genetic algorithm and ab initio atomistic thermodynamics under the framework of first-principles-based hybrid density functional theory to study the (meta-)stability of a wide range of Li(x)N(y) clusters. We found that hybrid xc-functional is essential to address this problem as a local/semilocal functional simply fails even to predict a qualitative prediction. Most importantly, we find that though in bulk lithium nitride, the Li-rich phase, that is, Li3N, is the stable stoichiometry; in small Li(x)N(y) clusters, N-rich phases are more stable at thermodynamic equilibrium. We further show that these N-rich clusters are promising hydrogen storage material because of their easy adsorption and desorption ability at respectively low (≤300 K) and moderately high temperature (≥600 K).

Hydrogen sensor

Science.gov (United States)

Duan, Yixiang; Jia, Quanxi; Cao, Wenqing

2010-11-23

A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

Massive Cerebral Gas Embolism under Discectomy due to Hydrogen Peroxide Irrigation

Directory of Open Access Journals (Sweden)

Junjie Zhang

2015-01-01

Full Text Available Massive cerebral and spinal gas embolism occurs rarely as a complication of discectomy. We report a 54-year-old female who had undergone a discectomy (L3/4 and L4/5 under epidural anesthesia in a local hospital developed multiple massive gas embolisms. At closure, surgeons irrigated the incision wound with hydrogen peroxide. Soon after the irrigation, the patient suddenly developed tachycardia, hypotension, and rapid oxygen desaturation. Subsequently, patient progressed into unconsciousness and right hemianopsia quadriplegia. Computed tomography (CT scan showed multiple hypointensity spots around the brain due to cerebral gas embolism, which indicated the pneumoencephalos. The likely mechanism was the absorption of hydrogen peroxide into blood. When the amount of oxygen evolved exceeded its maximal blood solubility, venous embolization occurred. Though the patient was treated with supportive treatments and hyperbaric oxygen, she did not get full recovery and was left with severe long-term cerebral injury.

Hydrogen production with fully integrated fuel cycle gas and vapour core reactors

International Nuclear Information System (INIS)

Anghaie, S.; Smith, B.

2004-01-01

This paper presents results of a conceptual design study involving gas and vapour core reactors (G/VCR) with a combined scheme to generate hydrogen and power. The hydrogen production schemes include high temperature electrolysis as well as two dominant thermochemical hydrogen production processes. Thermochemical hydrogen production processes considered in this study included the calcium-bromine process and the sulphur-iodine processes. G/VCR systems are externally reflected and moderated nuclear energy systems fuelled by stable uranium compounds in gaseous or vapour phase that are usually operated at temperatures above 1500 K. A gas core reactor with a condensable fuel such as uranium tetrafluoride (UF 4 ) or a mixture of UF 4 and other metallic fluorides (BeF 2 , LiF, KF, etc.) is commonly known as a vapour core reactor (VCR). The single most relevant and unique feature of gas/vapour core reactors is that the functions of fuel and coolant are combined into one. The reactor outlet temperature is not constrained by solid fuel-cladding temperature limits. The maximum fuel/working fluid temperature in G/VCR is only constrained by the reactor vessel material limits, which is far less restrictive than the fuel clad. Therefore, G/VCRs can potentially provide the highest reactor and cycle temperature among all existing or proposed fission reactor designs. Gas and vapour fuel reactors feature very low fuel inventory and fully integrated fuel cycle that provide for exceptional sustainability and safety characteristics. With respect to fuel utilisation, there is no fuel burn-up limit for gas core reactors due to continuous recycling of the fuel. Owing to the flexibility in nuclear design characteristics of cavity reactors, a wide range of conversion ratio from completely burner to breeder is achievable. The continuous recycling of fuel in G/VCR systems allow for complete burning of actinides without removing and reprocessing of the fuel. The only waste products at the back

The Effects of Added Hydrogen on Noble Gas Discharges Used as Ambient Desorption/Ionization Sources for Mass Spectrometry

Science.gov (United States)

Ellis, Wade C.; Lewis, Charlotte R.; Openshaw, Anna P.; Farnsworth, Paul B.

2016-09-01

We demonstrate the effectiveness of using hydrogen-doped argon as the support gas for the dielectric barrier discharge (DBD) ambient desorption/ionization (ADI) source in mass spectrometry. Also, we explore the chemistry responsible for the signal enhancement observed when using both hydrogen-doped argon and hydrogen-doped helium. The hydrogen-doped argon was tested for five analytes representing different classes of molecules. Addition of hydrogen to the argon plasma gas enhanced signals for gas-phase analytes and for analytes coated onto glass slides in positive and negative ion mode. The enhancements ranged from factors of 4 to 5 for gas-phase analytes and factors of 2 to 40 for coated slides. There was no significant increase in the background. The limit of detection for caffeine was lowered by a factor of 79 using H2/Ar and 2 using H2/He. Results are shown that help explain the fundamental differences between the pure-gas discharges and those that are hydrogen-doped for both argon and helium. Experiments with different discharge geometries and grounding schemes indicate that observed signal enhancements are strongly dependent on discharge configuration.

Electricity and gas market design to supply the German transport sector with hydrogen

International Nuclear Information System (INIS)

Robinius, Martin

2015-01-01

The German government has set targets to reduce greenhouse gas emissions by 40% by 2020, 55% by 2030, 70% by 2040 and 80-95% by 2050 compared to 1990 as reference year. As well as meeting other requirements, these targets can be achieved by raising the contribution of renewably-generated power to Germany's gross electricity consumption to 80% by 2050. Based on Germany's potential, intermittent energy sources (IES) such as on- and offshore wind, as well as photovoltaics, are necessary sources that must be utilized in order to achieve these ambitious targets. Because of the intermittency of these sources, there will be times in which surplus power generated could be used for example for the transport sector. During these periods of surplus power, the storage capacity of hydrogen allows for a socalled ''power-to-gas'' concept whereby the surplus power can be used to produce hydrogen and oxygen by means of electrolyzers. The aim of this thesis is to identify and develop a market design that is characterized by high penetration levels of IES, supplemented by the use of hydrogen in the transport sector. Furthermore, the aim was to develop a model in which the electricity and gas sector, including a hydrogen pipeline grid, is represented so as to analyze and validate selected market designs. Therefore, potential electricity and gas markets, as well as the most important potential share and stakeholders of a hydrogen infrastructure, are analyzed. With the model developed in this thesis, an existing energy concept has been developed, analyzed and evaluated. In addition, the distribution of the hydrogen production costs was calculated by employing a Monte Carlo Simulation analysis. The developed energy concept relies on 170 GW onshore and 60 GW offshore wind capacity and these dominate the model. This leads to surplus power, especially in the federal states of Lower Saxony, Schleswig-Holstein and Mecklenburg-Western Pomerania. To supply the

Visualization of hydrogen gas evolution during deformation and fracture in SCM 440 steel with different tempering conditions

Energy Technology Data Exchange (ETDEWEB)

Horikawa, Keitaro, E-mail: horikawa@me.es.osaka-u.ac.jp [Department of Mechanical Science and Bioengineering, School of Engineering Science, Osaka University, Toyonaka 560-8531 (Japan); Ando, Nobuaki; Kobayashi, Hidetoshi [Department of Mechanical Science and Bioengineering, School of Engineering Science, Osaka University, Toyonaka 560-8531 (Japan); Urushihara, Wataru [Surface Design and Corrosion Research Section, Materials Research Laboratory, Kobe Steel, Ltd., Kobe 651-2271 (Japan)

2012-02-01

Highlights: Black-Right-Pointing-Pointer We visualize emission sites of hydrogen atoms on the microstructures during deformation. Black-Right-Pointing-Pointer Hydrogen atoms are emitted from slip lines and inclusions when deformed. Black-Right-Pointing-Pointer We show the sequence of hydrogen gas evolution during deformation. Black-Right-Pointing-Pointer Hydrogen evolution amount will increase if the steels with high strength are tested. - Abstract: In the present study, the hydrogen gas evolution behavior was investigated in SCM 440 steel by using a hydrogen microprint technique (HMT) and a testing machine equipped with a quadrupole mass spectrometer (QMS) in a ultrahigh vacuum (UHV) atmosphere. SCM 440 steels prepared by varying the tempering temperature over the range 200-700 Degree-Sign C were evaluated in order to elucidate the relationship between the hydrogen gas evolution and the tempered microstructures in the deformation. Cathodic hydrogen charging was carried out with a current density of 100 A/m{sup 2} for 1 h at room temperature. For comparison, a tensile specimen was prepared without hydrogen charging. The HMT showed that silver particles, which are indicative of the hydrogen emission sites, were present mainly in the matrix as well as on the slip lines after the deformation. It is believed that the silver particles on the slip lines represent the effect of hydrogen transportation due to mobile dislocations. In addition, accumulation of silver particles around non-metallic inclusions such as Al{sub 2}O{sub 3} was also identified. This tendency was observed for different tempering conditions. From the relationship between the stress-strain curves and the hydrogen evolution, determined by using QMS under a UHV atmosphere, it was found that the hydrogen gas evolution behavior varied with the deformation stage.

One-dimensional magnetohydrodynamic calculations of a hydrogen-gas puff

International Nuclear Information System (INIS)

Maxon, S.; Nielsen, P.D.

1981-01-01

A one-dimensional Lagrangian calculation of the implosion of a hydrogen gas puff is presented. At maximum compression, 60% of the mass is located in a density spike .5 mm off the axis with a half width of 40 μm. The temperature on axis reaches 200 eV

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

Alkaline hydrothermal de-ashing and desulfurization of low quality coal and its application to hydrogen-rich gas generation

International Nuclear Information System (INIS)

Mursito, Anggoro Tri; Hirajima, Tsuyoshi; Sasaki, Keiko

2011-01-01

This paper describes experimental research and a fundamental study of alkaline hydrothermal treatment of high-sulfur, high-ash coal from Banten, Java-Indonesia. Experiments were carried out on a laboratory-scale 0.5 L batch reactor. The alkaline hydrothermal treatment gave upgraded clean coal with low sulfur content (about 0.3 wt.%) and low ash content (about 2.1 wt.%). A zero carbon dioxide and pure hydrogen gas were produced at 330 o C by introducing an alkali (sodium hydroxide, NaOH) to the hydrothermal treatment of raw coal. X-ray diffraction (XRD) and X-ray fluorescence (XRF) techniques were used to test for the removal or reduction of major inorganic elements in the coal, and changes in carbon-functional groups and their properties were determined by Fourier transform infrared spectroscopy (FTIR) and Carbon-13 of nuclear magnetic resonance ( 13 C NMR) tests on the product of the hydrothermal upgrading and demineralization process.

Hydrogen isotope effect through Pd in hydrogen transport pipe

International Nuclear Information System (INIS)

Tamaki, Masayoshi

1992-01-01

This investigation concerns hydrogen system with hydrogen transport pipes for transportation, purification, isotope separation and storage of hydrogen and its isotopes. A principle of the hydrogen transport pipe (heat pipe having hydrogen transport function) was proposed. It is comprised of the heat pipe and palladium alloy tubes as inlet, outlet, and the separation membrane of hydrogen. The operation was as follows: (1) gas was introduced into the heat pipe through the membrane in the evaporator; (2) the introduced gas was transported toward the condenser by the vapor flow; (3) the transported gas was swept and compressed to the end of the condenser by the vapor pressure; and (4) the compressed gas was exhausted from the heat pipe through the membrane in the condenser. The characteristics of the hydrogen transport pipe were examined for various working conditions. Basic performance concerning transportation, evacuation and compression was experimentally verified. Isotopic dihydrogen gases (H 2 and D 2 ) were used as feed gas for examining the intrinsic performance of the isotope separation by the hydrogen transport pipe. A simulated experiment for hydrogen isotope separation was carried out using a hydrogen-helium gas mixture. The hydrogen transport pipe has a potential for isotope separation and purification of hydrogen, deuterium and tritium in fusion reactor technology. (author)

Fiber optic hydrogen gas sensor utilizing surface plasmon resonance and native defects of zinc oxide by palladium

International Nuclear Information System (INIS)

Tabassum, Rana; Gupta, Banshi D

2016-01-01

We present an experimental study on a surface plasmon resonance (SPR) based fiber optic hydrogen gas sensor employing a palladium doped zinc oxide nanocomposite (ZnO (1−x) Pd x , 0 ≤ x ≤ 0.85) layer over the silver coated unclad core of the fiber. Palladium doped zinc oxide nanocomposites (ZnO (1−x) Pd x )  are prepared by a chemical route for different composition ratios and their structural, morphological and hydrogen sensing properties are investigated experimentally. The sensing principle involves the absorption of hydrogen gas by ZnO (1−x) Pd x , altering its dielectric function. The change in the dielectric constant is analyzed in terms of the red shift of the resonance wavelength in the visible region of the electromagnetic spectrum. To check the sensing capability of sensing probes fabricated with varying composition ratio (x) of nanocomposite, the SPR curves are recorded typically for 0% H 2 and 4% H 2 in N 2 atmosphere for each fabricated probe. On changing the concentration of hydrogen gas from 0% to 4%, the red shift in the SPR spectrum confirms the change in dielectric constant of ZnO (1−x) Pd x on exposure to hydrogen gas. It is noted that the shift in the SPR spectrum increases monotonically up to a certain fraction of Pd in zinc oxide, beyond which it starts decreasing. SEM images and the photoluminescence (PL) spectra reveal that Pd dopant atoms substitutionally incorporated into the ZnO lattice profoundly affect its defect levels; this is responsible for the optimal composition of ZnO (1−x) Pd x to sense the hydrogen gas. The sensor is highly selective to hydrogen gas and possesses high sensitivity. Since optical fiber sensing technology is employed along with the SPR technique, the present sensor is capable of remote sensing and online monitoring of hydrogen gas. (paper)

Gas-Rich Mergers in LCDM: Disk Survivability and the Baryonic Assembly of Galaxies

International Nuclear Information System (INIS)

Stewart, K.

2009-01-01

We use N-body simulations and observationally-normalized relations between dark matter halo mass, stellar mass, and cold gas mass to derive robust expectations about the baryonic content of major mergers out to redshift z ∼ 2. First, we find that the majority of major mergers (m/M > 0.3) experienced by Milky Way size dark matter halos should have been gas-rich, and that gas-rich mergers are increasingly common at high redshift. Though the frequency of major mergers into galaxy halos in our simulations greatly exceeds the observed late-type galaxy fraction, the frequency of gas-poor major mergers is consistent with the observed fraction of bulge-dominated galaxies across the halo mass range M DM ∼ 10 11 - 10 13 M · . These results lend support to the conjecture that mergers with high baryonic gas fractions play an important role in building and/or preserving disk galaxies in the universe. Secondly, we find that there is a transition mass below which a galaxy's past major mergers were primarily gas-rich and above which they were gas poor. The associated stellar mass scale corresponds closely to that marking the observed bimodal division between blue, star-forming, disk-dominated systems and red, bulge-dominated systems with old populations. Finally, we find that the overall fraction of a galaxy's cold baryons deposited directly via major mergers is substantial. Approximately 30% of the cold baryonic material in M star ∼ 10 10 M · (M DM ∼ 10 11.5 M · ) galaxies is accreted as cold gas in major mergers. For more massive galaxies with M star ∼ 10 11 M · (M DM ∼ 10 13 M · the fraction of baryons amassed in mergers is even higher, ∼ 50%, but most of these accreted baryons are delivered directly in the form of stars. This baryonic mass deposition is almost unavoidable, and provides a limit on the fraction of a galaxy's cold baryons that can originate in cold flows or from hot halo cooling

Performance of the CAPRICE98 balloon-borne gas-RICH detector

CERN Document Server

Bergström, D; Carlson, P J; Francke, T; Grinstein, S; Weber, N; Suffert, Martin; Hof, M; Kremer, J; Menn, W; Simon, M; Stephens, S A; Ambriola, M; Bellotti, R; Cafagna, F; Castellano, M G; Ciacio, F; Circella, M; De Marzo, C; Finetti, N; Papini, P; Piccardi, S; Spillantini, P; Bartalucci, S; Ricci, M; Bidoli, V; Casolino, M; De Pascale, M P; Morselli, A; Picozza, P; Sparvoli, R; Barbiellini, Guido; Schiavon, R P; Vacchi, A; Zampa, N; Mitchell, J W; Ormes, J F; Streitmatter, R E; Bravar, U; Stochaj, S J

2001-01-01

A RICH counter using a gas radiator of C/sub 4/F/sub 10/ and a photosensitive MWPC with pad readout has been developed, tested in particle beam at CERN and used in the CAPRICE98 balloon-borne experiment. The MWPC was operated with a TMAE and ethane mixture at atmospheric pressure and used a cathode pad plane to give an unambiguous image of the Cherenkov light. The induced signals in the pad plane were read our using the AMPLEX chip and CRAMS. The good efficiency of the Cherenkov light collection, the efficient detection of the weak signal from single UV photons together with a low noise level in the electronics of the RICH detector, resulted in a large number of detected photoelectrons per event. For beta approximately=1 charge one particles, an average of 12 photoelectrons per event were detected. The reconstructed Cherenkov angle of 50 mrad for a beta approximately=1 particle had a resolution of 1.2 mrad (rms). The RICH was flown with the CAPRICE98 magnetic spectrometer and was the first RICH counter ever u...

SLOWLY ROTATING GAS-RICH GALAXIES IN MODIFIED NEWTONIAN DYNAMICS (MOND)

International Nuclear Information System (INIS)

Sánchez-Salcedo, F. J.; Martínez-García, E. E.; Hidalgo-Gámez, A. M.

2013-01-01

We have carried out a search for gas-rich dwarf galaxies that have lower rotation velocities in their outskirts than MOdified Newtonian Dynamics (MOND) predicts, so that the amplitude of their rotation curves cannot be fitted by arbitrarily increasing the mass-to-light ratio of the stellar component or by assuming additional undetected matter. With presently available data, the gas-rich galaxies UGC 4173, Holmberg II, ESO 245-G05, NGC 4861, and ESO 364-G029 deviate most from MOND predictions and, thereby, provide a sample of promising targets in testing the MOND framework. In the case of Holmberg II and NGC 4861, we find that their rotation curves are probably inconsistent with MOND, unless their inclinations and distances differ significantly from the nominal ones. The galaxy ESO 364-G029 is a promising target because its baryonic mass and rotation curve are similar to Holmberg II but presents a higher inclination. Deeper photometric and H I observations of ESO 364-G029, together with further decreasing systematic uncertainties, may provide a strong test to MOND.

Gas Phase Fabrication of Pd-Ni Nanoparticle Arrays for Hydrogen Sensor Applications

Directory of Open Access Journals (Sweden)

Peng Xing

2015-01-01

Full Text Available Pd-Ni nanoparticles have been fabricated by gas aggregation process. The formation of Pd-Ni nano-alloys was confirmed by X-ray photoelectron spectroscopy measurements. By depositing Pd-Ni nanoparticles on the interdigital electrodes, quantum conductance-based hydrogen sensors were fabricated. The Ni content in the nanoparticle showed an obvious effect on the hydrogen response behavior corresponding to the conductance change of the nanoparticle film. Three typical response regions with different conductance-hydrogen pressure correlations were observed. It was found that the α-β phase transition region of palladium hydride moves to significant higher hydrogen pressure with the addition of nickel element, which greatly enhance the hydrogen sensing performance of the nanoparticle film.

Catalytic Steam Reforming of Bio-Oil to Hydrogen Rich Gas

DEFF Research Database (Denmark)

Trane-Restrup, Rasmus

heating value and high content of oxygen, which makes it unsuited for direct utilization in engines. One prospective technology for upgrading of bio-oil is steam reforming (SR), which can be used to produce H2 for upgrading of bio-oil through hydrodeoxygenation or synthesis gas for processes like......-oil. There are two main pathways to minimize carbon deposition in steam reforming; either through optimization of catalyst formulation or through changes to the process parameters, like changes in temperature, steam to carbon ratio (S/C), or adding O2 or H2 to the feed. In this thesis both pathways have been...

Study on atmospheric hydrogen enrichment by cryopump method and isotope separation by gas chromatography

International Nuclear Information System (INIS)

Taniyama, Yuki; Momoshima, Noriyuki

2001-01-01

To obtain the information of source of atmospheric hydrogen tritium an analysis of tritium isotopes is thought to be effective. So an atmospheric hydrogen enrichment apparatus and a cryogenic gas chromatographic column were made. Experiments were carried out to study the performance of cryopump to enrich atmospheric hydrogen and the column to separate hydrogen isotopes that obtained by cryopump method. The cryopump was able to process about 1000 1 atmosphere and the column was able to separate hydrogen isotopes with good resolution. (author)

Improved Hydrogen Gas Getters for TRU Waste Transuranic and Mixed Waste Focus Area - Phase 2 Final Report

Energy Technology Data Exchange (ETDEWEB)

Stone, Mark Lee

2002-04-01

Alpha radiolysis of hydrogenous waste and packaging materials generates hydrogen gas in radioactive storage containers. For that reason, the Nuclear Regulatory Commission (NRC) limits the flammable gas (hydrogen) concentration in the Transuranic Package Transporter-II (TRUPACT-II) containers to 5 vol% of hydrogen in air, which is the lower explosion limit. Consequently, a method is needed to prevent the build up of hydrogen to 5 vol% during the storage and transport of the TRUPACT-II containers (up to 60 days). One promising option is the use of hydrogen getters. These materials scavenge hydrogen from the gas phase and irreversibly bind it in the solid phase. One proven getter is a material called 1,4-bis (phenylethynyl) benzene, or DEB. It has the needed binding rate and capacity, but some of the chemical species that might be present in the containers could interfere with its ability to remove hydrogen. This project is focused upon developing a protective polymeric membrane coating for the DEB getter material, which comes in the form of small, irregularly shaped particles. This report summarizes the experimental results of the second phase of the development of the materials.

Chromatographic measurement of hydrogen isotopic and permanent gas impurities in tritium

International Nuclear Information System (INIS)

Warner, D.K.; Kinard, C.; Bohl, D.C.

1976-01-01

This paper describes a gas chromatograph that was designed for dedicated analysis of hydrogen isotopic and permanent gas impurities in tritium and tritium-deuterium mixtures. The instrument that was developed substantially improved the accuracy and precision of hydrogen isotopic analysis in the 20 ppM to one mole percent range as compared with other analytical methods. Several unique design features of the instrument were required due to the radiation and isotopic exchange properties of the tritium in the samples; descriptions of these features are presented along with details of the complete chromatographic system. The experimental procedures used to calibrate the detector and statistically evaluate its performance are given, and the sources of analytical error are cited. The limitations of the present system are also discussed

Effects of hydrogen gas on properties of tin-doped indium oxide films deposited by radio frequency magnetron sputtering method

International Nuclear Information System (INIS)

Kim, Do-Geun; Lee, Sunghun; Lee, Gun-Hwan; Kwon, Sik-Chol

2007-01-01

Tin-doped indium oxide (ITO) films were deposited at ∼ 70 deg. C of substrate temperature by radio frequency magnetron sputtering method using an In 2 O 3 -10% SnO 2 target. The effect of hydrogen gas ratio [H 2 / (H 2 + Ar)] on the electrical, optical and mechanical properties was investigated. With increasing the amount of hydrogen gas, the resistivity of the samples showed the lowest value of 3.5 x 10 -4 Ω.cm at the range of 0.8-1.7% of hydrogen gas ratio, while the resistivity increases over than 2.5% of hydrogen gas ratio. Hall effect measurements explained that carrier concentration and its mobility are strongly related with the resistivity of ITO films. The supplement of hydrogen gas also reduced the residual stress of ITO films up to the stress level of 110 MPa. The surface roughness and the crystallinity of the samples were investigated by using atomic force microscopy and x-ray diffraction, respectively

A pyrolysis/gas chromatographic method for the determination of hydrogen in solid samples

Science.gov (United States)

Carr, R. H.; Bustin, R.; Gibson, E. K.

1987-01-01

A method is described for the determination of hydrogen in solid samples. The sample is heated under vacuum after which the evolved gases are separated by gas chromatography with a helium ionization detector. The system is calibrated by injecting known amounts of hydrogen, as determined manometrically. The method, which is rapid and reliable, was checked for a variety of lunar soils; the limit of detection is about 10 ng of hydrogen.

Exergy and thermoeconomic evaluation of hydrogen production from natural gas; Avaliacao exergetica e termo-economica da producao de hidrogenio a partir do gas natural

Energy Technology Data Exchange (ETDEWEB)

Cruz, Flavio Eduardo da [PROMON Engenharia Ltda., Sao Paulo, SP (Brazil); Oliveira Junior, Silvio de [Universidade de Sao Paulo (USP), SP (Brazil). Escola Politecnica

2008-07-01

Some specific processes are required to obtain pure hydrogen and the most usual one is the natural gas reforming, where natural gas reacts with superheated steam producing H{sub 2}, CO, CO{sub 2} and H{sub 2}O. This paper presents exergy and thermoeconomic analysis of a complete hydrogen production unit of a petroleum refinery. The hydrogen production unit analysed in this paper has to supply 550,000 Nm{sup 3} of hydrogen per day to purify diesel oil. Based on a synthesis plant of the hydrogen production unit, the exergy efficiency of each component and of the overall plant are calculated. The hydrogen production cost is determined by means of a thermoeconomic analysis in which the equality cost partition method is employed, including capital and operational costs, in order to determine the production cost of hydrogen and other products of the plant.(author)

A compressed hydrogen gas storage system with an integrated phase change material

DEFF Research Database (Denmark)

Mazzucco, Andrea; Rothuizen, Erasmus Damgaard; Jørgensen, Jens Erik

2015-01-01

below the critical temperature of 85 °C, while filling the hydrogen at ambient temperature. Results show that a 10-mm-thick layer of paraffin wax can absorb enough heat to reduce the adiabatic temperature by 20 K when compared to a standard Type IV tank. The heat transfer from the gas to the phase...... change material, mainly occurs after the fueling is completed, resulting in a higher hydrogen peak temperature inside the tank and a lower fuelled mass than a gas-cooled system. Such a mass reduction accounts for 12% with respect to the case of a standard tank system fuelled at -40 °C....

Natural gas usage as a heat source for integrated SMR and thermochemical hydrogen production technologies

International Nuclear Information System (INIS)

Jaber, O.; Naterer, G.F.; Dincer, I.

2010-01-01

This paper investigates various usages of natural gas (NG) as an energy source for different hydrogen production technologies. A comparison is made between the different methods of hydrogen production, based on the total amount of natural gas needed to produce a specific quantity of hydrogen, carbon dioxide emissions per mole of hydrogen produced, water requirements per mole of hydrogen produced, and a cost sensitivity analysis that takes into account the fuel cost, carbon dioxide capture cost and a carbon tax. The methods examined are the copper-chlorine (Cu-Cl) thermochemical cycle, steam methane reforming (SMR) and a modified sulfur-iodine (S-I) thermochemical cycle. Also, an integrated Cu-Cl/SMR plant is examined to show the unique advantages of modifying existing SMR plants with new hydrogen production technology. The analysis shows that the thermochemical Cu-Cl cycle out-performs the other conventional methods with respect to fuel requirements, carbon dioxide emissions and total cost of production. (author)

Influence of fillers on hydrogen penetration properties and blister fracture of rubber composites for O-ring exposed to high-pressure hydrogen gas

Energy Technology Data Exchange (ETDEWEB)

Yamabe, Junichiro; Nishimura, Shin [Department of Mechanical Science Engineering, Kyushu University, 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan); Research Center for Hydrogen Industrial Use and Storage (HYDROGENIUS), National Institute of Advanced Industrial Science and Technology (AIST), 744 Motooka, Nishi-ku, Fukuoka 819-0395 (Japan)

2009-02-15

Ethylene-propylene rubber (EPDM) and nitrile-butadiene rubber (NBR) composites having carbon black, silica, and no fillers were exposed to hydrogen gas at a maximum pressure of 10 MPa; then, blister tests and the measurement of hydrogen content were conducted. The hydrogen contents of the composites were proportional to the hydrogen pressure, i.e., the behavior of their hydrogen contents follows Henry's law. This implies that hydrogen penetrates into the composite as a hydrogen molecule. The addition of carbon black raised the hydrogen content of the composite, while the addition of silica did not. Based on observations, the blister damages of composites with silica were less pronounced, irrespective of the hydrogen pressures. This may be attributed to their lower hydrogen content and relatively better tensile properties than the others. (author)

Sensitization of erbium in silicon-rich silica : the effect of annealing temperature and hydrogen passivation

International Nuclear Information System (INIS)

Wilkinson, A.R.; Forcales, M.; Elliman, R.G.

2005-01-01

This paper reports on the effect of annealing temperature and hydrogen passivation on the excitation cross-section and photoluminescence of erbium in silicon-rich silica. Samples were prepared by co-implantation of Si and Er into SiO 2 followed by a single thermal anneal at temperatures ranging from 800 to 1100 degrees C, and with or without hydrogen passivation performed at 500 degrees C. Using time-resolved photoluminescence, the effective erbium excitation cross-section is shown to increase by a factor 3, while the number of optically active erbium ions decreases by a factor of 4 with increasing annealing temperature. Hydrogen passivation is shown to increase the luminescence intensity and to shorten the luminescence lifetime at 1.54 μm only in the presence of Si nanocrystals. The implications fo these results for realizing a silicon-based optical amplifier are also discussed. (author). 19 refs., 3 figs

Study of Catalyst Variation Effect in Glycerol Conversion Process to Hydrogen Gas by Steam Reforming

Science.gov (United States)

Widayat; Hartono, R.; Elizabeth, E.; Annisa, A. N.

2018-04-01

Along with the economic development, needs of energy being increase too. Hydrogen as alternative energy has many usages. Besides that, hydrogen is one source of energy that is a clean fuel, but process production of hydrogen from natural gas as a raw material has been used for a long time. Therefore, there is need new invention to produce hydrogen from the others raw material. Glycerol, a byproduct of biodiesel production, is a compound which can be used as a raw material for hydrogen production. By using glycerol as a raw material of hydrogen production, we can get added value of glycerol as well as an energy source solution. The process production of hydrogen by steam reforming is a thermochemical process with efficiency 70%. This process needs contribution of catalyst to improve its efficiency and selectivity of the process. In this study will be examined the effect variation of catalyst for glycerol conversion process to hydrogen by steam reforming. The method for catalyst preparation was variation of catalyst impregnation composition, catalyst calcined with difference concentration of hydrochloric acid and calcined with difference hydrochloric acid ratio. After that, all of catalyst which have been prepared, used for steam reforming process for hydrogen production from glycerol as a raw material. From the study, the highest yield of hydrogen gas showed in the process production by natural zeolite catalyst with 1:15 Hydrochloric acid ratio was 42.28%. Hydrogen yield for 2M calcined natural zeolite catalyst was 38.37%, for ZSM-5 catalyst was 15.83%, for 0.5M calcined natural zeolite was 13.09% and for ultrasonic natural zeolite was 11.43%. The lowest yield of hydrogen gas showed in catalyst 2Zn/ZSM-5 with 11.22%. This result showed that hydrogen yield product was affected by catalyst variation because of the catalyst has difference characteristic and difference catalytic activity after the catalyst preparation process.

Hydrogen from catalytic reforming of biomass-derived hydrocarbons in liquid water

Science.gov (United States)

Cortright, R. D.; Davda, R. R.; Dumesic, J. A.

2002-08-01

Concerns about the depletion of fossil fuel reserves and the pollution caused by continuously increasing energy demands make hydrogen an attractive alternative energy source. Hydrogen is currently derived from nonrenewable natural gas and petroleum, but could in principle be generated from renewable resources such as biomass or water. However, efficient hydrogen production from water remains difficult and technologies for generating hydrogen from biomass, such as enzymatic decomposition of sugars, steam-reforming of bio-oils and gasification, suffer from low hydrogen production rates and/or complex processing requirements. Here we demonstrate that hydrogen can be produced from sugars and alcohols at temperatures near 500K in a single-reactor aqueous-phase reforming process using a platinum-based catalyst. We are able to convert glucose-which makes up the major energy reserves in plants and animals-to hydrogen and gaseous alkanes, with hydrogen constituting 50% of the products. We find that the selectivity for hydrogen production increases when we use molecules that are more reduced than sugars, with ethylene glycol and methanol being almost completely converted into hydrogen and carbon dioxide. These findings suggest that catalytic aqueous-phase reforming might prove useful for the generation of hydrogen-rich fuel gas from carbohydrates extracted from renewable biomass and biomass waste streams.

Development of a new method for hydrogen isotope analysis of trace hydrocarbons in natural gas samples

Directory of Open Access Journals (Sweden)

Xibin Wang

2016-12-01

Full Text Available A new method had been developed for the analysis of hydrogen isotopic composition of trace hydrocarbons in natural gas samples by using solid phase microextraction (SPME combined with gas chromatography-isotope ratio mass spectrometry (GC/IRMS. In this study, the SPME technique had been initially introduced to achieve the enrichment of trace content of hydrocarbons with low abundance and coupled to GC/IRMS for hydrogen isotopic analysis. The main parameters, including the equilibration time, extraction temperature, and the fiber type, were systematically optimized. The results not only demonstrated that high extraction yield was true but also shows that the hydrogen isotopic fractionation was not observed during the extraction process, when the SPME device fitted with polydimethylsiloxane/divinylbenzene/carbon molecular sieve (PDMS/DVB/CAR fiber. The applications of SPME-GC/IRMS method were evaluated by using natural gas samples collected from different sedimentary basins; the standard deviation (SD was better than 4‰ for reproducible measurements; and also, the hydrogen isotope values from C1 to C9 can be obtained with satisfying repeatability. The SPME-GC/IRMS method fitted with PDMS/DVB/CAR fiber is well suited for the preconcentration of trace hydrocarbons, and provides a reliable hydrogen isotopic analysis for trace hydrocarbons in natural gas samples.

Mechanical test of E110 cladding material oxidized in hydrogen rich steam atmosphere

International Nuclear Information System (INIS)

Windberg, P.; Perez-Fero, E.

2005-01-01

The behavior of the fuel cladding under accidental conditions has been studied at the AEKI for more than a decade. Earlier, the effect of oxygen and hydrogen content on the mechanical properties was studied separately. The present experiments can help to understand what kind of processes took place in the cleaning tank at Paks NPP (2003). The purpose of our experiments was to investigate high temperature oxidation of E110 cladding in steam + hydrogen mixture. A high temperature tube furnace was used for oxidation of the samples. The oxidation was carried out at three different temperatures (900 0 C, 1000 0 C, 1100 0 C). The hydrogen content in the steam was varied between 19-36 vol%. The oxygen content of the sample was defined as oxidation ratio. Two sizes (length: 2 and 8 mm) of cladding rings and 100 mm long E110 cladding tubes were oxidized. After the oxidation we made compression and tensile tests for rings, and ballooning experiments for 100 mm long tube. The most important conclusions were the following. Oxidation in H-rich steam atmosphere need longer time to get the same oxidation ratio compared to the steam oxidation without hydrogen. The shorter oxidation time results in a more compact oxide layer. The longer oxidation time leads to a cracked oxide layer. (author)

Hydrogen-rich Water Exerting a Protective Effect on Ovarian Reserve Function in a Mouse Model of Immune Premature Ovarian Failure Induced by Zona Pellucida 3

Science.gov (United States)

He, Xin; Wang, Shu-Yu; Yin, Cheng-Hong; Wang, Tong; Jia, Chan-Wei; Ma, Yan-Min

2016-01-01

Background: Premature ovarian failure (POF) is a disease that affects female fertility but has few effective treatments. Ovarian reserve function plays an important role in female fertility. Recent studies have reported that hydrogen can protect male fertility. Therefore, we explored the potential protective effect of hydrogen-rich water on ovarian reserve function through a mouse immune POF model. Methods: To set up immune POF model, fifty female BALB/c mice were randomly divided into four groups: Control (mice consumed normal water, n = 10), hydrogen (mice consumed hydrogen-rich water, n = 10), model (mice were immunized with zona pellucida glycoprotein 3 [ZP3] and consumed normal water, n = 15), and model-hydrogen (mice were immunized with ZP3 and consumed hydrogen-rich water, n = 15) groups. After 5 weeks, mice were sacrificed. Serum anti-Müllerian hormone (AMH) levels, granulosa cell (GC) apoptotic index (AI), B-cell leukemia/lymphoma 2 (Bcl-2), and BCL2-associated X protein (Bax) expression were examined. Analyses were performed using SPSS 17.0 (SPSS Inc., Chicago, IL, USA) software. Results: Immune POF model, model group exhibited markedly reduced serum AMH levels compared with those of the control group (5.41 ± 0.91 ng/ml vs. 16.23 ± 1.97 ng/ml, P = 0.033) and the hydrogen group (19.65 ± 7.82 ng/ml, P = 0.006). The model-hydrogen group displayed significantly higher AMH concentrations compared with that of the model group (15.03 ± 2.75 ng/ml vs. 5.41 ± 0.91 ng/ml, P = 0.021). The GC AI was significantly higher in the model group (21.30 ± 1.74%) than those in the control (7.06 ± 0.27%), hydrogen (5.17 ± 0.41%), and model-hydrogen groups (11.24 ± 0.58%) (all P hydrogen group compared with that of the hydrogen group (11.24 ± 0.58% vs. 5.17 ± 0.41%, P = 0.021). Compared with those of the model group, ovarian tissue Bcl-2 levels increased (2.18 ± 0.30 vs. 3.01 ± 0.33, P = 0.045) and the Bax/Bcl-2 ratio decreased in the model-hydrogen group

Gas Phase Hydrogenation of Levulinic Acid to gamma-Valerolactone

NARCIS (Netherlands)

Bonrath, Werner; Castelijns, Anna Maria Cornelia Francisca; de Vries, Johannes Gerardus; Guit, Rudolf Philippus Maria; Schuetz, Jan; Sereinig, Natascha; Vaessen, Henricus Wilhelmus Leonardus Marie

The gas phase hydrogenation of levulinic acid to gamma-valerolactone over copper and ruthenium based catalysts in a continuous fixed-bed reactor system was investigated. Among the catalysts a copper oxide based one [50-75 % CuO, 20-25 % SiO2, 1-5 % graphite, 0.1-1 % CuCO3/Cu(OH)(2)] gave

Thermodynamic analyses of hydrogen production from sub-quality natural gas. Part I: Pyrolysis and autothermal pyrolysis

Science.gov (United States)

Huang, Cunping; T-Raissi, Ali

Sub-quality natural gas (SQNG) is defined as natural gas whose composition exceeds pipeline specifications of nitrogen, carbon dioxide (CO 2) and/or hydrogen sulfide (H 2S). Approximately one-third of the U.S. natural gas resource is sub-quality gas [1]. Due to the high cost of removing H 2S from hydrocarbons using current processing technologies, SQNG wells are often capped and the gas remains in the ground. We propose and analyze a two-step hydrogen production scheme using SQNG as feedstock. The first step of the process involves hydrocarbon processing (via steam-methane reformation, autothermal steam-methane reformation, pyrolysis and autothermal pyrolysis) in the presence of H 2S. Our analyses reveal that H 2S existing in SQNG is stable and can be considered as an inert gas. No sulfur dioxide (SO 2) and/or sulfur trioxide (SO 3) is formed from the introduction of oxygen to SQNG. In the second step, after the separation of hydrogen from the main stream, un-reacted H 2S is used to reform the remaining methane, generating more hydrogen and carbon disulfide (CS 2). Thermodynamic analyses on SQNG feedstock containing up to 10% (v/v) H 2S have shown that no H 2S separation is required in this process. The Part I of this paper includes only thermodynamic analyses for SQNG pyrolysis and autothermal pyrolysis.

Lunar-derived titanium alloys for hydrogen storage

Science.gov (United States)

Love, S.; Hertzberg, A.; Woodcock, G.

1992-01-01

Hydrogen gas, which plays an important role in many projected lunar power systems and industrial processes, can be stored in metallic titanium and in certain titanium alloys as an interstitial hydride compound. Storing and retrieving hydrogen with titanium-iron alloy requires substantially less energy investment than storage by liquefaction. Metal hydride storage systems can be designed to operate at a wide range of temperatures and pressures. A few such systems have been developed for terrestrial applications. A drawback of metal hydride storage for lunar applications is the system's large mass per mole of hydrogen stored, which rules out transporting it from earth. The transportation problem can be solved by using native lunar materials, which are rich in titanium and iron.

Measurement and interpretation of threshold stress intensity factors for steels in high-pressure hydrogen gas.

Energy Technology Data Exchange (ETDEWEB)

Dadfarnia, Mohsen (University of Illinois at Urbana-Champaign, Urbana, IL); Nibur, Kevin A.; San Marchi, Christopher W.; Sofronis, Petros (University of Illinois at Urbana-Champaign, Urbana, IL); Somerday, Brian P.; Foulk, James W., III; Hayden, Gary A. (CP Industries, McKeesport, PA)

2010-07-01

Threshold stress intensity factors were measured in high-pressure hydrogen gas for a variety of low alloy ferritic steels using both constant crack opening displacement and rising crack opening displacement procedures. The sustained load cracking procedures are generally consistent with those in ASME Article KD-10 of Section VIII Division 3 of the Boiler and Pressure Vessel Code, which was recently published to guide design of high-pressure hydrogen vessels. Three definitions of threshold were established for the two test methods: K{sub THi}* is the maximum applied stress intensity factor for which no crack extension was observed under constant displacement; K{sub THa} is the stress intensity factor at the arrest position for a crack that extended under constant displacement; and K{sub JH} is the stress intensity factor at the onset of crack extension under rising displacement. The apparent crack initiation threshold under constant displacement, K{sub THi}*, and the crack arrest threshold, K{sub THa}, were both found to be non-conservative due to the hydrogen exposure and crack-tip deformation histories associated with typical procedures for sustained-load cracking tests under constant displacement. In contrast, K{sub JH}, which is measured under concurrent rising displacement and hydrogen gas exposure, provides a more conservative hydrogen-assisted fracture threshold that is relevant to structural components in which sub-critical crack extension is driven by internal hydrogen gas pressure.

The Influence of Hydrogen Gas on the Measures of Efficiency of Diesel Internal Combustion Engine

Directory of Open Access Journals (Sweden)

Jurgis Latakas

2014-12-01

Full Text Available In this research paper energy and ecological parameters of diesel engine which works under addition of hydrogen (10, 20, 30 l/ min are presented. A survey of research literature has shown that addition of hydrogen gases improve diesel combustion; increase indicated pressure; decrease concentration of carbon dioxide (CO2, hydrocarbons (HC, particles; decrease fuel consumptions. Results of the experiment revealed that hydrogen gas additive decreased pressure in cylinder in kinetic combustion phase. Concentration of CO2 and nitrous oxides (NOx decreased not significantly, HC – increased. Concentration of particles in engine exhaust gases significantly decreased. In case when hydrogen gas as additive was supplied, the fuel consumptions decreased a little. Using AVL BOOST software combustion process analysis was made. It was determined that in order to optimize engine work process under hydrogen additive usage, it is necessary to adjust diesel injection angle.

Applications of ion implantation for modifying the interactions between metals and hydrogen gas

Science.gov (United States)

Musket, R. G.

1989-04-01

Ion implantations into metals have been shown recently to either reduce or enhance interactions with gaseous hydrogen. Published studies concerned with modifications of these interactions are reviewed and discussed in terms of the mechanisms postulated to explain the observed changes. The interactions are hydrogenation, hydrogen permeation, and hydrogen embrittlement. In particular, the results of the reviewed studies are (a) uranium hydriding suppressed by implantation of oxygen and carbon, (b) hydrogen gettered in iron and nickel using implantation of titanium, (c) hydriding of titanium catalyzed by implanted palladium, (d) tritium permeation of 304L stainless steel reduced using selective oxidation of implanted aluminum, and (e) hydrogen attack of a low-alloy steel accelerated by implantation of helium. These studies revealed ion implantation to be an effective method for modifying the interactions of hydrogen gas with metals.

Population inversion in a recombining hydrogen plasma interacting with a helium gas

International Nuclear Information System (INIS)

Oda, Toshiatsu; Furukane, Utaro.

1984-08-01

A numerical investigation has shown that the population inversion between the levels with the principal quantum number i=2 and 3 takes place in a recombining hydrogen plasma which is interacting with a cool and dense helium gas on the basis of a collisional- radiative (CR) model. Overpopulation density Δn 32 , which is defined as the difference between the population densities per unit statistical weight of the upper and lower excited levels 3 and 2, is found to be much higher than a threshold level for the laser oscillation in the quasi-steady state when the hydrogen plasma with nsub(e) = 10 13 --10 14 cm -3 interacts with the helium gas with pressure of --50 Torr. (author)

Gas-rich galaxy pair unveiled in the lensed quasar 0957+561

Science.gov (United States)

Planesas; Martin-Pintado; Neri; Colina

1999-12-24

Molecular gas in the host galaxy of the lensed quasar 0957+561 (QSO 0957+561) at the redshift of 1.41 has been detected in the carbon monoxide (CO) line. This detection shows the extended nature of the molecular gas distribution in the host galaxy and the pronounced lensing effects due to the differentially magnified CO luminosity at different velocities. The estimated mass of molecular gas is about 4 x 10(9) solar masses, a molecular gas mass typical of a spiral galaxy like the Milky Way. A second, weaker component of CO is interpreted as arising from a close companion galaxy that is rich in molecular gas and has remained undetected so far. Its estimated molecular gas mass is 1.4 x 10(9) solar masses, and its velocity relative to the main galaxy is 660 kilometers per second. The ability to probe the molecular gas distribution and kinematics of galaxies associated with high-redshift lensed quasars can be used to improve the determination of the Hubble constant H(0).

Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

International Nuclear Information System (INIS)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2010-01-01

Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

Mitigation of Hydrogen Gas Generation from the Reaction of Water with Uranium Metal in K Basins Sludge

Energy Technology Data Exchange (ETDEWEB)

Sinkov, Sergey I.; Delegard, Calvin H.; Schmidt, Andrew J.

2010-01-29

Means to decrease the rate of hydrogen gas generation from the chemical reaction of uranium metal with water were identified by surveying the technical literature. The underlying chemistry and potential side reactions were explored by conducting 61 principal experiments. Several methods achieved significant hydrogen gas generation rate mitigation. Gas-generating side reactions from interactions of organics or sludge constituents with mitigating agents were observed. Further testing is recommended to develop deeper knowledge of the underlying chemistry and to advance the technology aturation level. Uranium metal reacts with water in K Basin sludge to form uranium hydride (UH3), uranium dioxide or uraninite (UO2), and diatomic hydrogen (H2). Mechanistic studies show that hydrogen radicals (H·) and UH3 serve as intermediates in the reaction of uranium metal with water to produce H2 and UO2. Because H2 is flammable, its release into the gas phase above K Basin sludge during sludge storage, processing, immobilization, shipment, and disposal is a concern to the safety of those operations. Findings from the technical literature and from experimental investigations with simple chemical systems (including uranium metal in water), in the presence of individual sludge simulant components, with complete sludge simulants, and with actual K Basin sludge are presented in this report. Based on the literature review and intermediate lab test results, sodium nitrate, sodium nitrite, Nochar Acid Bond N960, disodium hydrogen phosphate, and hexavalent uranium [U(VI)] were tested for their effects in decreasing the rate of hydrogen generation from the reaction of uranium metal with water. Nitrate and nitrite each were effective, decreasing hydrogen generation rates in actual sludge by factors of about 100 to 1000 when used at 0.5 molar (M) concentrations. Higher attenuation factors were achieved in tests with aqueous solutions alone. Nochar N960, a water sorbent, decreased hydrogen

Gas-Rich Mergers in LCDM: Disk Survivability and the Baryonic Assembly of Galaxies

Energy Technology Data Exchange (ETDEWEB)

Stewart, Kyle R.; Bullock, James S.; /UC, Irvine; Wechsler, Risa H.; /KIPAC, Menlo Park /SLAC; Maller, Ariyeh H.; /New York City Coll. Tech.

2009-08-03

We use N-body simulations and observationally-normalized relations between dark matter halo mass, stellar mass, and cold gas mass to derive robust expectations about the baryonic content of major mergers out to redshift z {approx} 2. First, we find that the majority of major mergers (m/M > 0.3) experienced by Milky Way size dark matter halos should have been gas-rich, and that gas-rich mergers are increasingly common at high redshift. Though the frequency of major mergers into galaxy halos in our simulations greatly exceeds the observed late-type galaxy fraction, the frequency of gas-poor major mergers is consistent with the observed fraction of bulge-dominated galaxies across the halo mass range M{sub DM} {approx} 10{sup 11} - 10{sup 13} M{sub {circle_dot}}. These results lend support to the conjecture that mergers with high baryonic gas fractions play an important role in building and/or preserving disk galaxies in the universe. Secondly, we find that there is a transition mass below which a galaxy's past major mergers were primarily gas-rich and above which they were gas poor. The associated stellar mass scale corresponds closely to that marking the observed bimodal division between blue, star-forming, disk-dominated systems and red, bulge-dominated systems with old populations. Finally, we find that the overall fraction of a galaxy's cold baryons deposited directly via major mergers is substantial. Approximately 30% of the cold baryonic material in M{sub star} {approx} 10{sup 10} M{sub {circle_dot}} (M{sub DM} {approx} 10{sup 11.5} M{sub {circle_dot}}) galaxies is accreted as cold gas in major mergers. For more massive galaxies with M{sub star} {approx} 10{sup 11} M{sub {circle_dot}} (M{sub DM} {approx} 10{sup 13} M{sub {circle_dot}} the fraction of baryons amassed in mergers is even higher, {approx} 50%, but most of these accreted baryons are delivered directly in the form of stars. This baryonic mass deposition is almost unavoidable, and provides a

Hydrate dissociation conditions for gas mixtures containing carbon dioxide, hydrogen, hydrogen sulfide, nitrogen, and hydrocarbons using SAFT

International Nuclear Information System (INIS)

Li Xiaosen; Wu Huijie; Li Yigui; Feng Ziping; Tang Liangguang; Fan Shuanshi

2007-01-01

A new method, a molecular thermodynamic model based on statistical mechanics, is employed to predict the hydrate dissociation conditions for binary gas mixtures with carbon dioxide, hydrogen, hydrogen sulfide, nitrogen, and hydrocarbons in the presence of aqueous solutions. The statistical associating fluid theory (SAFT) equation of state is employed to characterize the vapor and liquid phases and the statistical model of van der Waals and Platteeuw for the hydrate phase. The predictions of the proposed model were found to be in satisfactory to excellent agreement with the experimental data

Greenhouse gas reduction benefits and costs of a large-scale transition to hydrogen in the USA

International Nuclear Information System (INIS)

Dougherty, William; Kartha, Sivan; Lazarus, Michael; Fencl, Amanda; Rajan, Chella; Bailie, Alison; Runkle, Benjamin

2009-01-01

Hydrogen is an energy carrier able to be produced from domestic, zero-carbon sources and consumed by zero-pollution devices. A transition to a hydrogen-based economy could therefore potentially respond to climate, air quality, and energy security concerns. In a hydrogen economy, both mobile and stationary energy needs could be met through the reaction of hydrogen (H 2 ) with oxygen (O 2 ). This study applies a full fuel cycle approach to quantify the energy, greenhouse gas emissions (GHGs), and cost implications associated with a large transition to hydrogen in the United States. It explores a national and four metropolitan area transitions in two contrasting policy contexts: a 'business-as-usual' (BAU) context with continued reliance on fossil fuels, and a 'GHG-constrained' context with policies aimed at reducing greenhouse gas emissions. A transition in either policy context faces serious challenges, foremost among them from the highly inertial investments over the past century or so in technology and infrastructure based on petroleum, natural gas, and coal. A hydrogen transition in the USA could contribute to an effective response to climate change by helping to achieve deep reductions in GHG emissions by mid-century across all sectors of the economy; however, these reductions depend on the use of hydrogen to exploit clean, zero-carbon energy supply options. (author)

Greenhouse gas reduction benefits and costs of a large-scale transition to hydrogen in the USA

Energy Technology Data Exchange (ETDEWEB)

Dougherty, William; Kartha, Sivan; Lazarus, Michael; Fencl, Amanda [Stockholm Environment Institute - US Center, 11 Curtis Avenue, Somerville, MA 02143 (United States); Rajan, Chella [Indian Institute of Technology Madras, I.I.T. Post Office, Chennai 600 036 (India); Bailie, Alison [The Pembina Institute, 200, 608 - 7th Street, S.W. Calgary, AB (Canada); Runkle, Benjamin [Department of Civil and Environmental Engineering, University of California, Berkeley, CA 94720 (United States)

2009-01-15

Hydrogen is an energy carrier able to be produced from domestic, zero-carbon sources and consumed by zero-pollution devices. A transition to a hydrogen-based economy could therefore potentially respond to climate, air quality, and energy security concerns. In a hydrogen economy, both mobile and stationary energy needs could be met through the reaction of hydrogen (H{sub 2}) with oxygen (O{sub 2}). This study applies a full fuel cycle approach to quantify the energy, greenhouse gas emissions (GHGs), and cost implications associated with a large transition to hydrogen in the United States. It explores a national and four metropolitan area transitions in two contrasting policy contexts: a 'business-as-usual' (BAU) context with continued reliance on fossil fuels, and a 'GHG-constrained' context with policies aimed at reducing greenhouse gas emissions. A transition in either policy context faces serious challenges, foremost among them from the highly inertial investments over the past century or so in technology and infrastructure based on petroleum, natural gas, and coal. A hydrogen transition in the USA could contribute to an effective response to climate change by helping to achieve deep reductions in GHG emissions by mid-century across all sectors of the economy; however, these reductions depend on the use of hydrogen to exploit clean, zero-carbon energy supply options. (author)

Highly Sensitive and Selective Hydrogen Gas Sensor Using the Mesoporous SnO2 Modified Layers

Directory of Open Access Journals (Sweden)

Niuzi Xue

2017-10-01

Full Text Available It is important to improve the sensitivities and selectivities of metal oxide semiconductor (MOS gas sensors when they are used to monitor the state of hydrogen in aerospace industry and electronic field. In this paper, the ordered mesoporous SnO2 (m-SnO2 powders were prepared by sol-gel method, and the morphology and structure were characterized by X-ray diffraction analysis (XRD, transmission electron microscope (TEM and Brunauer–Emmett–Teller (BET. The gas sensors were fabricated using m-SnO2 as the modified layers on the surface of commercial SnO2 (c-SnO2 by screen printing technology, and tested for gas sensing towards ethanol, benzene and hydrogen with operating temperatures ranging from 200 °C to 400 °C. Higher sensitivity was achieved by using the modified m-SnO2 layers on the c-SnO2 gas sensor, and it was found that the S(c/m2 sensor exhibited the highest response (Ra/Rg = 22.2 to 1000 ppm hydrogen at 400 °C. In this paper, the mechanism of the sensitivity and selectivity improvement of the gas sensors is also discussed.

Biological fermentative hydrogen production from olive pulp at 35 degrees C

Energy Technology Data Exchange (ETDEWEB)

Koutrouli, E.C.; Gavala, H.N.; Skiadas, I.V.; Lyberatos, G. [Patras Univ., Patras (Greece). Dept. of Chemical Engineering

2004-07-01

In response to energy security and environmental concerns, there is renewed interest in the use of hydrogen gas as a renewable energy source. However, many processes for generating hydrogen are extremely energy intensive and costly. This study focused on biological production of hydrogen from wastewater or other biomass. Photosynthetic and fermentation processes were outlined, but the main focus of this paper was on continuous anaerobic fermentation of low cost substrates such as olive pulp at 35 degrees C. This process is linked to the acidogenic stage of anaerobic digestion where carbohydrates are the preferred carbon source. Volatile fatty acids and alcohols are produced simultaneously with the hydrogen gas. An added advantage is that the effluent from the fermentation process can be further used by methanogenesis due to its rich organic acids content. Batch experiments with olive pulp resulted in 2.5 mmole of hydrogen per gram of total carbohydrates. It was noted that more research is required to maximize hydrogen production in a continuous process. It was suggested that hydrogen production could be optimized through hydrolysis of the non-soluble carbohydrates. This could be accomplished through physicochemical or biological pretreatments. 7 refs., 3 tabs., 1 fig.

Molecular Hydrogen as an Emerging Therapeutic Medical Gas for Neurodegenerative and Other Diseases

Directory of Open Access Journals (Sweden)

Kinji Ohno

2012-01-01

Full Text Available Effects of molecular hydrogen on various diseases have been documented for 63 disease models and human diseases in the past four and a half years. Most studies have been performed on rodents including two models of Parkinson's disease and three models of Alzheimer's disease. Prominent effects are observed especially in oxidative stress-mediated diseases including neonatal cerebral hypoxia; Parkinson's disease; ischemia/reperfusion of spinal cord, heart, lung, liver, kidney, and intestine; transplantation of lung, heart, kidney, and intestine. Six human diseases have been studied to date: diabetes mellitus type 2, metabolic syndrome, hemodialysis, inflammatory and mitochondrial myopathies, brain stem infarction, and radiation-induced adverse effects. Two enigmas, however, remain to be solved. First, no dose-response effect is observed. Rodents and humans are able to take a small amount of hydrogen by drinking hydrogen-rich water, but marked effects are observed. Second, intestinal bacteria in humans and rodents produce a large amount of hydrogen, but an addition of a small amount of hydrogen exhibits marked effects. Further studies are required to elucidate molecular bases of prominent hydrogen effects and to determine the optimal frequency, amount, and method of hydrogen administration for each human disease.

Molecular Hydrogen as an Emerging Therapeutic Medical Gas for Neurodegenerative and Other Diseases

Science.gov (United States)

Ohno, Kinji; Ito, Mikako; Ichihara, Masatoshi; Ito, Masafumi

2012-01-01

Effects of molecular hydrogen on various diseases have been documented for 63 disease models and human diseases in the past four and a half years. Most studies have been performed on rodents including two models of Parkinson's disease and three models of Alzheimer's disease. Prominent effects are observed especially in oxidative stress-mediated diseases including neonatal cerebral hypoxia; Parkinson's disease; ischemia/reperfusion of spinal cord, heart, lung, liver, kidney, and intestine; transplantation of lung, heart, kidney, and intestine. Six human diseases have been studied to date: diabetes mellitus type 2, metabolic syndrome, hemodialysis, inflammatory and mitochondrial myopathies, brain stem infarction, and radiation-induced adverse effects. Two enigmas, however, remain to be solved. First, no dose-response effect is observed. Rodents and humans are able to take a small amount of hydrogen by drinking hydrogen-rich water, but marked effects are observed. Second, intestinal bacteria in humans and rodents produce a large amount of hydrogen, but an addition of a small amount of hydrogen exhibits marked effects. Further studies are required to elucidate molecular bases of prominent hydrogen effects and to determine the optimal frequency, amount, and method of hydrogen administration for each human disease. PMID:22720117

Effects of hydrogen rich water on prolonged intermittent exercise.

Science.gov (United States)

Da Ponte, Alessandro; Giovanelli, Nicola; Nigris, Daniele; Lazzer, Stefano

2018-05-01

Recent studies showed a positive effect of hydrogen rich water (HRW) intake on acid-base homeostasis at rest. We investigated 2-weeks of HRW intake on repeated sprint performance and acid-base status during prolonged intermittent cycling exercise. In a cross over single-blind protocol, 8 trained male cyclists (age [mean±SD] 41±7 years, body mass 72.3±4.4 kg, height 1.77±0.04 m, maximal oxygen uptake [V̇O2max] 52.6±4.4 mL·kg-1·min-1) were provided daily with 2 liters of placebo normal water (PLA, pH 7.6, oxidation/reduction potential [ORP] +230 mV, free hydrogen content 0 ppb) or HRW (pH 9.8, ORP -180 mV, free Hydrogen 450 ppb). Tests were performed at baseline and after each period of 2 weeks of treatment. The treatments were counter-balanced and the sequence randomized. The 30-minute intermittent cycling trial consisted in 10 3-minute blocks, each one composed by 90 seconds at 40% V̇O2max, 60 seconds at 60% V̇O2max, 16 seconds all out sprint, and 14 seconds active recovery. Oxygen uptake (V̇O2), heart rate and power output were measured during the whole test, while mean and peak power output (PPO), time to peak power and Fatigue Index (FI) were determined during all the 16 seconds sprints. Lactate, pH and bicarbonate (HCO3-) concentrations were determined at rest and after each sprint on blood obtained by an antecubital vein indwelling catheter. In the PLA group, PPO in absolute values decreased significantly at the 8th and 9th of 10 sprints and in relative values, ΔPPO, decreased significantly at 6th, 8th and 9th of 10 sprints (by mean: -12±5%, Pmay help to maintain PPO in repetitive sprints to exhaustion over 30 minutes.

Internal combustion engines fueled by natural gas-hydrogen mixtures

Energy Technology Data Exchange (ETDEWEB)

Akansu, S.O.; Kahraman, N. [Erciyes University, Kayseri (Turkey). Engineering Faculty; Dulger, Z. [Kocaeli University (Turkey). Engineering Faculty; Veziroglu, T.N. [University of Miami, Coral Gables, FL (United States). College of Engineering

2004-11-01

In this study, a survey of research papers on utilization of natural gas-hydrogen mixtures in internal combustion engines is carried out. In general, HC, CO{sub 2}, and CO emissions decrease with increasing H{sub 2}, but NO{sub x} emissions generally increase. If a catalytic converter is used, NO{sub x} emission values can be decreased to extremely low levels. Consequently, equivalence zero emission vehicles (EZEV) standards may be reached. Efficiency values vary with H{sub 2} amount, spark timing, compression ratio, equivalence ratio, etc. Under certain conditions, efficiency values can be increased. In terms of BSFC, emissions and BTE, a mixture of low hydrogen percentage is suitable for using. (author)

A massive hydrogen-rich Martian greenhouse recorded in D/H

Science.gov (United States)

Pahlevan, K.; Schaefer, L. K.; Desch, S. J.; Elkins-Tanton, L. T.

2017-12-01

The deuterium-to-hydrogen (D/H) ratio in Martian atmospheric water ( 6x standard mean ocean water, SMOW) [1,2] is higher than that of known sources [3,4] alluding to a planetary enrichment process. A recent measurement by the Curiosity rover of Hesperian clays yields a D/H value 3x higher than SMOW [5], demonstrating that most enrichment occurred early in planetary history, buttressing the conclusions of Martian meteorite studies [6,7]. Extant models of the isotopic evolution of the Martian hydrosphere have not incorporated primordial H2, despite its likely abundance on early Mars. Here, we report the first 1D climate calculations with an atmospheric composition determined via degassing from a reducing magma ocean to study Martian climate during an early water ocean stage. A reducing Martian magma ocean is expected based on experimental petrology [8], the degassing of which gives rise to an H2-rich steam atmosphere [9] with strong attendant greenhouse warming [10,11] even after the removal of steam via condensation. At the pressures and temperatures prevailing in such a degassed greenhouse, we find that isotopic exchange in the fluid envelope is rapid, strongly concentrating deuterium in water molecules over molecular hydrogen [12]. The subsequent loss of the isotopically light H2-rich atmosphere results in a 2x D/H enrichment in the oceans via isotopic equilibration alone. These calculations suggest that most of the D/H enrichment observed in the first billion years of Martian history is produced by the evolution of a massive ( 100 bar) H2-rich greenhouse in the aftermath of magma ocean crystallization. The proposed link between early planetary process and modern isotopic observable opens a new window into the earliest history of Mars. [1] Owen, T. et al. Science 240, 1767-1770 (1988). [2] Webster, C. R. et al. Science 341, 260-263 (2013). [3] Lunine, J. I. et al. Icarus 165, 1-8, (2003). [4] Marty, B. et al. EPSL 441, 91-102, (2016). [5] Mahaffy, P. et al

Laboratory evaluation of the hydrogen sulfide gas treatment approach for remediation of chromate-, uranium(VI)-, and nitrate-contaminated soils

International Nuclear Information System (INIS)

Thornton, E.C.; Baechler, M.A.; Beck, M.A.; Amonette, J.E.

1994-08-01

Bench-scale soil treatment tests were conducted as part of an effort to develop and implement an in situ chemical treatment approach to the remediation of metal and radionuclide contaminated soils through the use of reactive gases. In general, > 90% immobilization of chromium and > 50% immobilization of uranium was achieved. Leach test results indicate that the treatment process is irreversible for chromium but partially reversible for uranium indicates that immobilization for this contaminant is more readily achieved in organic rich soils. This observation is ascribed to the reducing nature of organic matter. Additional tests were also conducted with soils contaminated to the 5,000 ppm level with nitrate. Nitrate was not found to interfere significantly with treatment of the contaminants. Nitrite was observed in the leachate samples obtained from tests with an organic-rich soil containing clay, however. Leachate chemistries suggested that no other significantly hazardous byproducts were generated by the treatment process and that soil alteration effects were minimal. Test results also suggest that treatment effectiveness is somewhat lower in very dry soils but still able to immobilize chromium and uranium to an acceptable degree. Results of these testing activities indicate that the concentration of hydrogen sulfide in the gas mixture is not a limited factor in treatment as long as a sufficient volume of the mixture is delivered to the soil to achieve a mole ratio of hydrogen sulfide to contaminant of at least 10

Applications of ion implantation for modifying the interactions between metals and hydrogen gas

International Nuclear Information System (INIS)

Musket, R.G.

1989-01-01

Ion implantations into metals have been shown recently to either reduce or enhance interactions with gaseous hydrogen. Published studies concerned with modifications of these interactions are reviewed and discussed in terms of the mechanisms postulated to explain the observed changes. The interactions are hydrogenation, hydrogen permeation and hydrogen embrittlement. In particular, the results of the reviewed studies are 1. uranium hydriding suppressed by implantation of oxygen and carbon, 2. hydrogen gettered in iron and nickel using implantation of titanium, 3. hydriding of titanium catalyzed by implanted palladium, 4. tritium permeation of 304L stainless steel reduced using selective oxidation of implanted aluminum, and 5. hydrogen attack of a low-alloy steel accelerated by implantation of helium. These studies revealed ion implantation to be an effective method for modifying the interactions of hydrogen gas with metals. (orig.)

Comparison of thermodynamic and environmental indexes of natural gas, syngas and hydrogen production processes

International Nuclear Information System (INIS)

Bargigli, Silvia; Raugei, Marco; Ulgiati, Sergio

2004-01-01

The thermodynamic efficiency and the environmental sustainability of selected processes that deliver gaseous energy carriers (natural gas, syngas from coal gasification, and hydrogen from steam reforming of natural gas and alkaline electrolysis) is explored by means of a multi-criteria, multi-scale approach based on four methods: material flow accounting, energy analysis, exergy analysis, and energy synthesis. The average energy and exergy conversion efficiencies of syngas (76% and 75%, respectively) are found to be higher than those for hydrogen (64% and 55%). However, coal-to-syngas conversion generates a significant amount of solid waste, which should be dealt with carefully. In addition, the material intensity is much higher for syngas (e.g. abiotic MI=768 g/g) than for natural gas and hydrogen (21 and 39 g/g, respectively), indicating a higher load on the environment. On the other hand, the energy intensity (transformity) for syngas (5.25x10 4 seJ/J) is shown to be lower than for hydrogen (9.66x10 4 seJ/J), indicating a lower demand for global environmental support. Therefore, material intensities and transformities offer two complementary pieces of information: transformities account for the 'memory' of the environmental resources that were used up in the past for the production of the inputs, whereas MIs are strictly calculated within the time frame of the life cycle of the investigated process. The higher transformity values calculated for pure hydrogen suggest careful and appropriate use of such an energy vector

Impacts of seasonality on hydrogen production using natural gas pressure letdown stations. Paper no. IGEC-1-083

International Nuclear Information System (INIS)

Maddaloni, J.; Rowe, A.; Bailey, R.; McDonald, D.

2005-01-01

One of the difficulties associated with the development of a hydrogen economy is the creation of a supply infrastructure. A means for distributed hydrogen generation through a process using the exergy in high pressure natural gas streams has been proposed. The system recovers energy via expansion of natural gas through a turbo-expander at existing pressure reduction systems. Generated electric power is then used to drive an electrolyzer and create hydrogen. A model of the process is used to determine production rates for electricity and hydrogen given flow data for a number of pressure letdown sites in BC. Like many traditional renewable energy sources, most letdown stations have strong annual variations in flow conditions. Annual variations in stream flow rate, inlet pressure and inlet temperature can greatly affect hydrogen production rates. In the model, component efficiencies are scaled for operation at part-load, or away from optimum design conditions. Results indicate a significant reduction in predicted hydrogen production rates as compared to installed component name-plate capacity. Operating the system with a 'grid-tie' can increase the capacity factor, but economic viability will depend on local electricity and natural gas prices. (author)

H2-rich fluids from serpentinization: Geochemical and biotic implications

OpenAIRE

Sleep, N. H.; Meibom, A.; Fridriksson, Th.; Coleman, R. G.; Bird, D. K.

2004-01-01

Metamorphic hydration and oxidation of ultramafic rocks produces serpentinites, composed of serpentine group minerals and varying amounts of brucite, magnetite, and/or FeNi alloys. These minerals buffer metamorphic fluids to extremely reducing conditions that are capable of producing hydrogen gas. Awaruite, FeNi3, forms early in this process when the serpentinite minerals are Fe-rich. Olivine with the current mantle Fe/Mg ratio was oxidized during serpentinization after the Moon-forming impac...

Hydrogen enrichment and separation from synthesis gas by the use of a membrane reactor

International Nuclear Information System (INIS)

Sanchez, J.M.; Barreiro, M.M.; Marono, M.

2011-01-01

One of the objectives of the CHRISGAS project was to study innovative gas separation and gas upgrading systems that have not been developed sufficiently yet to be tested at a demonstration scale within the time frame of the project, but which show some attractive merits and features for further development. In this framework CIEMAT studied, at bench scale, hydrogen enrichment and separation from syngas by the use of membranes and membrane catalytic reactors. In this paper results about hydrogen separation from synthesis gas by means of selective membranes are presented. Studies dealt with the evaluation of permeation and selectivity to hydrogen of prepared and pre-commercial Pd-based membranes. Whereas prepared membranes turned out to be non-selective, due to discontinuities of the palladium layer, studies conducted with the pre-commercial membrane showed that by means of a membrane reactor it is possible to completely separate hydrogen from the other gas components and produce pure hydrogen as a permeate stream, even in the case of complex reaction system (H 2 /CO/CO 2 /H 2 O) under WGS conditions gas mixtures. The advantages of using a water-gas shift membrane reactor (MR) over a traditional fixed bed reactor (TR) have also been studied. The experimental device included the pre-commercial Pd-based membrane and a commercial high temperature Fe-Cr-based, WGS catalyst, which was packed in the annulus between the membrane and the reactor outer shell. Results show that in the MR concept, removal of H 2 from the reaction side has a positive effect on WGS reaction, reaching higher CO conversion than in a traditional packed bed reactor at a given temperature. On increasing pressure on the reaction side permeation is enhanced and hence carbon monoxide conversion increases. -- Highlights: → H 2 enrichment and separation using a bench-scale membrane reactor MR is studied. → Permeation and selectivity to H 2 of Pd-based membranes was determined. → Complete separation

Lattice-enabled nuclear reactions in the nickel and hydrogen gas system

International Nuclear Information System (INIS)

Nagel, David J.

2015-01-01

Thousands of lattice-enabled nuclear reaction (LENR) experiments involving electrochemical loading of deuterium into palladium have been conducted and reported in hundreds of papers. But, it appears that the first commercial LENR power generators will employ gas loading of hydrogen onto nickel. This article reviews the scientific base for LENR in the gas-loaded Ni-H system, and some of the tests of pre-commercial prototype generators based on this combination. (author)

Modelling of fast hydrogen permeability of alloys for membrane gas separation

Science.gov (United States)

Zaika, Yu. V.; Rodchenkova, N. I.

2017-05-01

The method of measuring the specific hydrogen permeability is used to study various alloys that are promising for gas separation installations. The nonlinear boundary value problem of hydrogen permeability complying with the specific features of the experiment and its modifications taking into account the high transfer rate is presented. Substantial difference from the quasi-equilibrium model (Richardson approximation in the assumption of the equilibrium Sieverts' law near the surface) has been discussed. The model is tested on published experimental data on Ta77Nb23 alloy.

Lean-rich axial stage combustion in a can-annular gas turbine engine

Science.gov (United States)

Laster, Walter R.; Szedlacsek, Peter

2016-06-14

An apparatus and method for lean/rich combustion in a gas turbine engine (10), which includes a combustor (12), a transition (14) and a combustor extender (16) that is positioned between the combustor (12) and the transition (14) to connect the combustor (12) to the transition (14). Openings (18) are formed along an outer surface (20) of the combustor extender (16). The gas turbine (10) also includes a fuel manifold (28) to extend along the outer surface (20) of the combustor extender (16), with fuel nozzles (30) to align with the respective openings (18). A method (200) for axial stage combustion in the gas turbine engine (10) is also presented.

Hydrogen-rich medium protects mouse embryonic fibroblasts from oxidative stress by activating LKB1-AMPK-FoxO1 signal pathway.

Science.gov (United States)

Lee, Jihyun; Yang, Goowon; Kim, Young-Joo; Tran, Quynh Hoa; Choe, Wonchae; Kang, Insug; Kim, Sung Soo; Ha, Joohun

2017-09-23

Persistent oxidative stress is recognized as a major cause of many pathological conditions as well as ageing. However, most clinical trials of dietary antioxidants have failed to produce successful outcomes in treating oxidative stress-induced diseases. Molecular hydrogen (H 2 ) has recently received considerable attention as a therapeutic agent owing to its novel antioxidant properties, a selective scavenger of hydroxyl and peroxynitrite radicals. Beyond this, numerous reports support that H 2 can modulate the activity of various cellular signal pathways. However, its effect on AMP-activated protein kinase (AMPK) signal pathway, a central regulator of energy hemostasis, has remained almost elusive. Here, we report that hydrogen-rich medium activated LKB1-AMPK signal pathway without ATP depletion, which in turn induced FoxO1-dependent transcription of manganese superoxide dismutase and catalase in mouse embryonic fibroblasts. Moreover, hydrogen-rich media effectively reduced the level of reactive oxygen species in cells treated with hydrogen peroxide and protected these cells from apoptosis in an AMPK-dependent manner. These results suggest that the LKB1-AMPK-FoxO1 signaling pathway is a critical mediator of the antioxidant properties of H 2 , further supporting the idea that H 2 acts as a signaling molecule to serve various physiological functions. Copyright © 2017 Elsevier Inc. All rights reserved.

Hydrogen-rich saline controls remifentanil-induced hypernociception and NMDA receptor NR1 subunit membrane trafficking through GSK-3β in the DRG in rats.

Science.gov (United States)

Zhang, Linlin; Shu, Ruichen; Wang, Chunyan; Wang, Haiyun; Li, Nan; Wang, Guolin

2014-07-01

Although NMDAR trafficking mediated by GSK-3β involvement in transmission of pronociceptive messages in the spinal cord has been confirmed by our previous studies, whether NMDAR trafficking is implicated in peripheral sensitization remains equivocal. It is demonstrated that inflammation is associated with spinal NMDAR-containing nociceptive neurons activation and the maintenance of opioid induced pain hypersensitivity. However, whether and how hydrogen-rich saline, as an effective anti-inflammatory drug, could prevent hyperalgesia through affecting peripheral sensitization caused by NMDAR activation remains to be explored. To test these effects, hydrogen-rich saline (2.5, 5 or 10 ml/kg) was administrated intraperitoneally after remifentanil infusion, NMDAR antagonist MK-801 or GSK-3β inhibitor TDZD-8 was administrated intravenously before remifentanil infusion in rats. We examined time course of hydrogen concentration in blood after hydrogen-rich saline administration. Mechanical and thermal hyperalgesia were evaluated by measuring PWT and PWL for 48 post-infusion hours, respectively. Western blotting and real-time qPCR assay were applied to analyze the NR1 membrane trafficking, GSK-3β expression and activity in DRG. Inflammatory mediators (TNF-α, IL-1β, and IL-6) expressions in DRG were also analyzed. We found that NR1 membrane trafficking in DRG increased, possibly due to GSK-3β activation after remifentanil infusion. We also discovered that hydrogen-rich saline not 2.5 ml/kg but 5 and 10 ml/kg could dose-dependently attenuate mechanical and thermal hyperalgesia without affecting baseline nociceptive threshold, reduce expressions of inflammatory mediators (TNF-α, IL-1β, and IL-6) and decrease NR1 trafficking mediated by GSK-3β, and minimal effective concentration was observed to be higher than 10 μmol/L, namely peak concentration in arterial blood after administration of HRS 2.5 ml/kg without any influence on hyperalgesia. Our results indicated that

Palladium Gate All Around - Hetero Dielectric -Tunnel FET based highly sensitive Hydrogen Gas Sensor

Science.gov (United States)

Madan, Jaya; Chaujar, Rishu

2016-12-01

The paper presents a novel highly sensitive Hetero-Dielectric-Gate All Around Tunneling FET (HD-GAA-TFET) based Hydrogen Gas Sensor, incorporating the advantages of band to band tunneling (BTBT) mechanism. Here, the Palladium supported silicon dioxide is used as a sensing media and sensing relies on the interaction of hydrogen with Palladium-SiO2-Si. The high surface to volume ratio in the case of cylindrical GAA structure enhances the fortuities for surface reactions between H2 gas and Pd, and thus improves the sensitivity and stability of the sensor. Behaviour of the sensor in presence of hydrogen and at elevated temperatures is discussed. The conduction path of the sensor which is dependent on sensors radius has also been varied for the optimized sensitivity and static performance analysis of the sensor where the proposed design exhibits a superior performance in terms of threshold voltage, subthreshold swing, and band to band tunneling rate. Stability of the sensor with respect to temperature affectability has also been studied, and it is found that the device is reasonably stable and highly sensitive over the bearable temperature range. The successful utilization of HD-GAA-TFET in gas sensors may open a new door for the development of novel nanostructure gas sensing devices.

Highly sensitive work function hydrogen gas sensor based on PdNPs/SiO2/Si structure at room temperature

Directory of Open Access Journals (Sweden)

G. Behzadi pour

Full Text Available In this study, fabrication of highly sensitive PdNPs/SiO2/Si hydrogen gas sensor using experimental and theoretical methods has been investigated. Using chemical method the PdNPs are synthesized and characterized by X-ray diffraction (XRD. The average size of PdNPs is 11 nm. The thickness of the oxide film was 20 nm and the surface of oxide film analyzed using Atomic-force microscopy (AFM. The C-V curve for the PdNPs/SiO2/Si hydrogen gas sensor in 1% hydrogen concentration and at the room temperature has been reported. The response time and recovery time for 1% hydrogen concentration at room temperature were 1.2 s and 10 s respectively. The response (R% for PdNPs/SiO2/Si MOS capacitor hydrogen sensor was 96%. The PdNPs/SiO2/Si MOS capacitor hydrogen sensor showed very fast response and recovery times compared to SWCNTs/PdNPs, graphene/PdNPs, nanorod/PdNPs and nanowire/PdNPs hydrogen gas sensors. Keywords: Sensitive, Oxide film, Capacitive, Resistance

Numerical estimation of ultrasonic production of hydrogen: Effect of ideal and real gas based models.

Science.gov (United States)

Kerboua, Kaouther; Hamdaoui, Oualid

2018-01-01

Based on two different assumptions regarding the equation describing the state of the gases within an acoustic cavitation bubble, this paper studies the sonochemical production of hydrogen, through two numerical models treating the evolution of a chemical mechanism within a single bubble saturated with oxygen during an oscillation cycle in water. The first approach is built on an ideal gas model, while the second one is founded on Van der Waals equation, and the main objective was to analyze the effect of the considered state equation on the ultrasonic hydrogen production retrieved by simulation under various operating conditions. The obtained results show that even when the second approach gives higher values of temperature, pressure and total free radicals production, yield of hydrogen does not follow the same trend. When comparing the results released by both models regarding hydrogen production, it was noticed that the ratio of the molar amount of hydrogen is frequency and acoustic amplitude dependent. The use of Van der Waals equation leads to higher quantities of hydrogen under low acoustic amplitude and high frequencies, while employing ideal gas law based model gains the upper hand regarding hydrogen production at low frequencies and high acoustic amplitudes. Copyright © 2017 Elsevier B.V. All rights reserved.

The effect of the partial pressure of H2 gas and atomic hydrogen on diamond films deposited using CH3OH/H2O gas

International Nuclear Information System (INIS)

Lee, Kwon-Jai; Koh, Jae-Gui; Shin, Jae-Soo; Kwon, Ki-Hong; Lee, Chang-Hee

2006-01-01

Diamond films were deposited on Si(100) substrates by hot filament chemical vapor deposition (HFCVD) with a CH 3 OH/H 2 O gas mixture while changing the gas ratio. The films were analyzed with scanning electron microscopy (SEM), Raman spectroscopy, and optical emission spectroscopy (OES). The diamond films were grown with CH 3 OH being 52 % by volume of the gas mixture. The effect of atomic hydrogen on the film was different from that of the CH 4 /H 2 gas mixture. Analysis with OES during film growth indicated that among the thermally dissociated hydrogen radicals, only H α contributed to the etching of graphite.

Gas-controlled dynamic vacuum insulation with gas gate

Science.gov (United States)

Benson, D.K.; Potter, T.F.

1994-06-07

Disclosed is a dynamic vacuum insulation comprising sidewalls enclosing an evacuated chamber and gas control means for releasing hydrogen gas into a chamber to increase gas molecule conduction of heat across the chamber and retrieving hydrogen gas from the chamber. The gas control means includes a metal hydride that absorbs and retains hydrogen gas at cooler temperatures and releases hydrogen gas at hotter temperatures; a hydride heating means for selectively heating the metal hydride to temperatures high enough to release hydrogen gas from the metal hydride; and gate means positioned between the metal hydride and the chamber for selectively allowing hydrogen to flow or not to flow between said metal hydride and said chamber. 25 figs.

Erosion of graphite surface exposed to hot supersonic hydrogen gas

Science.gov (United States)

Sharma, O. P.

1972-01-01

A theoretical model based on laminar boundary layer flow equations was developed to predict the erosion rate of a graphite (AGCarb-101) surface exposed to a hot supersonic stream of hydrogen gas. The supersonic flow in the nozzle outside the boundary layer formed over the surface of the specimen was determined by assuming one-dimensional isentropic conditions. An overall surface reaction rate expression based on experimental studies was used to describe the interaction of hydrogen with graphite. A satisfactory agreement was found between the results of the computation, and the available experimental data. Some shortcomings of the model and further possible improvements are discussed.

Laboratory Studies of Hydrogen Gas Generation Using the Cobalt Chloride Catalyzed Sodium Borohydride-Water Reaction

Science.gov (United States)

2015-07-01

already use hydrogen for weather balloons . Besides cost, hydrogen has other advantages over helium. Hydrogen has more lift than helium, so larger...of water vapor entering the gas stream, and avoid damaging the balloon /aerostat (aerostats typically have an operational temperature range of -50 to...Aerostats: “Gepard” Tethered Aerostats with Mobile Mooring Systems. Available at http://rosaerosystems.com/aero/obj7. Accessed June 4, 2015. 11

Membrane reforming in converting natural gas to hydrogen: Production costs, Part II

Energy Technology Data Exchange (ETDEWEB)

Iaquaniello, G; Cosenza, S [Technip-KTI S.p.A., via Castello della Magliana 75, Rome (Italy); Giacobbe, F; Morico, B; Farace, A [Processi Innovativi s.r.l., L' Aquila (Italy)

2008-11-15

This paper evaluates the production costs of a hybrid system based on a new membrane reforming MRR concept to convert natural gas to hydrogen and electricity. Membrane reforming with hydrogen-selective, palladium-silver membranes pushes the chemical equilibrium and allows higher methane conversions at lower temperature such as 650 C. The new MRR concept formed of a series of modules is put forward herein. Each module is made up of a reforming step and an external membrane separation unit. The estimates, based on utilities costs of a typical Italian refinery (end of 2006), show that the production costs for the hybrid system are 30% less than conventional tubular steam reforming technology, and 13% less than a gas-fired cogeneration plant coupled with a conventional H{sub 2} plant. (author)

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

Thermochemical hydrogen generation of indium oxide thin films

Directory of Open Access Journals (Sweden)

Taekyung Lim

2017-03-01

Full Text Available Development of alternative energy resources is an urgent requirement to alleviate current energy constraints. As such, hydrogen gas is gaining attention as a future alternative energy source to address existing issues related to limited energy resources and air pollution. In this study, hydrogen generation by a thermochemical water-splitting process using two types of In2O3 thin films was investigated. The two In2O3 thin films prepared by chemical vapor deposition (CVD and sputtering deposition systems contained different numbers of oxygen vacancies, which were directly related to hydrogen generation. The as-grown In2O3 thin film prepared by CVD generated a large amount of hydrogen because of its abundant oxygen vacancies, while that prepared by sputtering had few oxygen vacancies, resulting in low hydrogen generation. Increasing the temperature of the In2O3 thin film in the reaction chamber caused an increase in hydrogen generation. The oxygen-vacancy-rich In2O3 thin film is expected to provide a highly effective production of hydrogen as a sustainable and efficient energy source.

Injection of a relativistic electron beam into neutral hydrogen gas

International Nuclear Information System (INIS)

de Haan, P.H.; Janssen, G.C.A.M.; Hopman, H.J.; Granneman, E.H.A.

1982-01-01

The injection of a relativistic electron beam (0.8 MeV, 6 kA, 150 nsec) into hydrogen gas of 190 Pa pressure results in a plasma with density n/sub e/approx. =10 20 m -3 and temperature kT/sub e/< or approx. =kT/sub i/approx. =3.5 eV. The results of the measurements show good agreement with computations based on a model combining gas ionization and turbulent plasma heating. It is found that a quasistationary state exists in which the energy lost by the beam (about 6% of the total kinetic energy of the beam) is partly used to further ionize and dissociate the gas and for the other part is lost as line radiation

Detection of Hydrogen Sulphide Gas Sensor Based Nanostructured Ba2CrMoO6 Thick Films

Directory of Open Access Journals (Sweden)

A. V. Kadu

2007-11-01

Full Text Available Nanocrystalline pure and doped Ba2CrMoO6, having an average crystallite size of 40 nm were synthesized by the sol-gel citrate method. Structural and gas-sensing characteristics were performed by using X-ray diffraction (XRD and sensitivity measurements. The gas sensing properties to reducing gases like Hydrogen sulphide (H2S, liquefied petroleum gas (LPG, carbon monoxide (CO and hydrogen gas (H2 were also discussed. The maximum sensitivity was obtained for 5 wt % Ni doped Ba2CrMoO6 at an operating temperature 250oC for H2S gas. Pd incorporation over 5 wt% Ni doped Ba2CrMoO6 improved the sensitivity, selectivity, response time, and reduced the operating temperature from 250 to 200oC of the sensor for H2S gas. This sensor also shows good satiability.

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

Role of technology in the U. K. gas industry. past, present, future

Energy Technology Data Exchange (ETDEWEB)

Evans, J W

1979-06-01

A discussion covers the beginning of public gas supply in the U.K.; the production of gas during coal combustion and the oil era; the development of LNG transport technology; the development of the Dent processes for producing gases from hydrocarbon feedstocks including the Catalytic Rich Gas and the Gas Recycle Hydrogenation processes; the growth of the natural gas transmission and distribution industry; the organization and functions of the British Gas Corp. Research and Development Division and Scientific Services; the various technological innovations being used in the transmission, distribution, domestic and industrial utilization sectors of the gas industry; the various efforts leading to the development of a commercial SNG process, based on the Lurgi coal gasifier operated under slagging conditions, that can handle a wide range of coals; and the outlook for future gas supply and demand, a hydrogen economy-based gas industry, and new developments affecting gas transmission and distribution, conservation and utilization.

ALMA Observations of Gas-rich Galaxies in z ∼ 1.6 Galaxy Clusters: Evidence for Higher Gas Fractions in High-density Environments

Energy Technology Data Exchange (ETDEWEB)

Noble, A. G.; McDonald, M. [Kavli Institute for Astrophysics and Space Research, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139 (United States); Muzzin, A. [Department of Physics and Astronomy, York University, 4700 Keele Street, Toronto, ON MJ3 1P3 (Canada); Nantais, J. [Departamento de Ciencias Físicas, Universidad Andres Bello, Fernandez Concha 700, Las Condes 7591538, Santiago, Región Metropolitana (Chile); Rudnick, G. [The University of Kansas, Department of Physics and Astronomy, 1251 Wescoe Hall Drive, Lawrence, KS 66045 (United States); Van Kampen, E.; Manilla-Robles, A. [European Southern Observatory, Karl-Schwarzschild-Strasse 2, D-85748 Garching bei München (Germany); Webb, T. M. A.; Delahaye, A. [Department of Physics, McGill University, 3600 rue University, Montréal, QC H3A 2T8 (Canada); Wilson, G.; DeGroot, A.; Foltz, R. [Department of Physics and Astronomy, University of California, Riverside, CA 92521 (United States); Yee, H. K. C. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Boone, K.; Hayden, B.; Perlmutter, S. [Department of Physics, University of California Berkeley, 366 LeConte Hall, MC 7300, Berkeley, CA 94720-7300 (United States); Cooper, M. C. [Department of Physics and Astronomy, University of California, Irvine, 4129 Frederick Reines Hall, Irvine, CA 92697 (United States); Demarco, R. [Departamento de Astronomía, Universidad de Concepción, Casilla 160-C, Concepción, Región del Biobío (Chile); Lidman, C., E-mail: noble@mit.edu [Australian Astronomical Observatory, 105 Delhi Road, North Ryde, NSW 2113 (Australia)

2017-06-20

We present ALMA CO (2–1) detections in 11 gas-rich cluster galaxies at z ∼ 1.6, constituting the largest sample of molecular gas measurements in z > 1.5 clusters to date. The observations span three galaxy clusters, derived from the Spitzer Adaptation of the Red-sequence Cluster Survey. We augment the >5 σ detections of the CO (2–1) fluxes with multi-band photometry, yielding stellar masses and infrared-derived star formation rates, to place some of the first constraints on molecular gas properties in z ∼ 1.6 cluster environments. We measure sizable gas reservoirs of 0.5–2 × 10{sup 11} M {sub ☉} in these objects, with high gas fractions ( f {sub gas}) and long depletion timescales ( τ ), averaging 62% and 1.4 Gyr, respectively. We compare our cluster galaxies to the scaling relations of the coeval field, in the context of how gas fractions and depletion timescales vary with respect to the star-forming main sequence. We find that our cluster galaxies lie systematically off the field scaling relations at z = 1.6 toward enhanced gas fractions, at a level of ∼4 σ , but have consistent depletion timescales. Exploiting CO detections in lower-redshift clusters from the literature, we investigate the evolution of the gas fraction in cluster galaxies, finding it to mimic the strong rise with redshift in the field. We emphasize the utility of detecting abundant gas-rich galaxies in high-redshift clusters, deeming them as crucial laboratories for future statistical studies.

Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic Matter

KAUST Repository

Logan, Bruce E.; Call, Douglas; Cheng, Shaoan; Hamelers, Hubertus V. M.; Sleutels, Tom H. J. A.; Jeremiasse, Adriaan W.; Rozendal, René A.

2008-01-01

production rates. MECs used to make hydrogen gas are similar in design to microbial fuel cells (MFCs) that produce electricity, but there are important differences in architecture and analytical methods used to evaluate performance. We review here

ALMA Shows that Gas Reservoirs of Star-forming Disks over the Past 3 Billion Years Are Not Predominantly Molecular

Energy Technology Data Exchange (ETDEWEB)

Cortese, Luca; Catinella, Barbara; Janowiecki, Steven, E-mail: luca.cortese@uwa.edu.au [International Centre for Radio Astronomy Research, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009 (Australia)

2017-10-10

Cold hydrogen gas is the raw fuel for star formation in galaxies, and its partition into atomic and molecular phases is a key quantity for galaxy evolution. In this Letter, we combine Atacama Large Millimeter/submillimeter Array and Arecibo single-dish observations to estimate the molecular-to-atomic hydrogen mass ratio for massive star-forming galaxies at z ∼ 0.2 extracted from the HIGHz survey, i.e., some of the most massive gas-rich systems currently known. We show that the balance between atomic and molecular hydrogen in these galaxies is similar to that of local main-sequence disks, implying that atomic hydrogen has been dominating the cold gas mass budget of star-forming galaxies for at least the past three billion years. In addition, despite harboring gas reservoirs that are more typical of objects at the cosmic noon, HIGHz galaxies host regular rotating disks with low gas velocity dispersions suggesting that high total gas fractions do not necessarily drive high turbulence in the interstellar medium.

The impact of natural gas/hydrogen mixtures on the performance of end-use equipment : Interchangeability analysis for domestic appliances

NARCIS (Netherlands)

de Vries, Harmen; Mokhov, Anatoli V.; Levinsky, Howard B.

2017-01-01

The addition of hydrogen derived from renewable power to the natural gas network is being promoted as a viable means of storing excess wind and solar energy. However, the changes in combustion properties of the natural gas upon hydrogen addition can impact the performance of the end-use equipment

ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT: BIOQUELL, INC. CLARIS C HYDROGEN PEROXIDE GAS GENERATOR

Science.gov (United States)

The Environmental Technology Verification report discusses the technology and performance of the Clarus C Hydrogen Peroxide Gas Generator, a biological decontamination device manufactured by BIOQUELL, Inc. The unit was tested by evaluating its ability to decontaminate seven types...

Upgrading of reformate gas for different applications with focus on small-scale hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Jannasch, Anna-Karin; Silversand, Fredrik [CATATOR AB, Lund (Sweden)

2004-12-01

Hydrogen gas or hydrogen rich gas is today used in many different applications, i.e. as fuel in fuel cells or additive in vehicle fuel (i.e. hythane) and as reagent or reducing agent in different industrial product lines. The majority of the hydrogen is produced either via electrolysis or reformation, where this work has entirely been focused on the latter alternative. The overarching aims of this project have been to demonstrate the need for reformate purification for different applications, and then, to investigate different available methods that can be used in order to enable the requested gas clean-up. The different purification methods have been examined with respect to parameters such as operating conditions (temperature, pressure), impurity tolerance, size, weight and cost. Another goal of the project has been to investigate how the reformer fuel type used influences the reformate gas quality and hence, the need for gas purification before the reformate can be fed to e.g. a low temperature polymer membrane fuel cell (PEMFC). For this reason, some experimental work has been performed. First, analysis of the reformate gas composition when natural gas, LPG, gasoline, diesel, kerosene (low and high S-concentration (i.e. JP8)) and ethanol have been processed. The reformation tests were carried out in a small scale reformer unit ({approx} 1 kW H{sub 2}) including Catator's catalyst formulations developed for the steam reforming, the water gas shift and the preferential oxidation reaction, respectively. Verification tests, with synthetic gas blends, including different potential reformate impurities, and with real reformate gas were thereafter performed with a commercial 4-cell PEMFC stack (3-5 W). Finally, some examination and also to some extent further development of Catator's existing gas purification units were made, i.e. chemical (WGS, PROX) and physical (regenerative adsorption). The Pd-alloy membrane seems to be the obvious choice of purification

The effect of a micro bubble dispersed gas phase on hydrogen isotope transport in liquid metals under nuclear irradiation

Energy Technology Data Exchange (ETDEWEB)

Fradera, J., E-mail: jfradera@ubu.es; Cuesta-López, S., E-mail: scuesta@ubu.es

2013-12-15

The present work intend to be a first step towards the understanding and quantification of the hydrogen isotope complex phenomena in liquid metals for nuclear technology. Liquid metals under nuclear irradiation in, e.g., breeding blankets of a nuclear fusion reactor would generate tritium which is to be extracted and recirculated as fuel. At the same time that tritium is bred, helium is also generated and may precipitate in the form of nano bubbles. Other liquid metal systems of a nuclear reactor involve hydrogen isotope absorption processes, e.g., tritium extraction system. Hence, hydrogen isotope absorption into gas bubbles modelling and control may have a capital importance regarding design, operation and safety. Here general models for hydrogen isotopes transport in liquid metal and absorption into gas phase, that do not depend on the mass transfer limiting regime, are exposed and implemented in OpenFOAM® CFD tool for 0D–3D simulations. Results for a 0D case show the impact of a He dispersed phase of nano bubbles on hydrogen isotopes inventory at different temperatures as well as the inventory evolution during a He nucleation event. In addition, 1D and 2D axisymmetric cases are exposed showing the effect of a He dispersed gas phase on hydrogen isotope permeation through a lithium lead eutectic alloy and the effect of vortical structures on hydrogen isotope transport at a backward facing step. Exposed results give a valuable insight on current nuclear technology regarding the importance of controlling hydrogen isotope transport and its interactions with nucleation event through gas absorption processes.

Hydrogen Embrittlement

Science.gov (United States)

Woods, Stephen; Lee, Jonathan A.

2016-01-01

Hydrogen embrittlement (HE) is a process resulting in a decrease in the fracture toughness or ductility of a metal due to the presence of atomic hydrogen. In addition to pure hydrogen gas as a direct source for the absorption of atomic hydrogen, the damaging effect can manifest itself from other hydrogen-containing gas species such as hydrogen sulfide (H2S), hydrogen chloride (HCl), and hydrogen bromide (HBr) environments. It has been known that H2S environment may result in a much more severe condition of embrittlement than pure hydrogen gas (H2) for certain types of alloys at similar conditions of stress and gas pressure. The reduction of fracture loads can occur at levels well below the yield strength of the material. Hydrogen embrittlement is usually manifest in terms of singular sharp cracks, in contrast to the extensive branching observed for stress corrosion cracking. The initial crack openings and the local deformation associated with crack propagation may be so small that they are difficult to detect except in special nondestructive examinations. Cracks due to HE can grow rapidly with little macroscopic evidence of mechanical deformation in materials that are normally quite ductile. This Technical Memorandum presents a comprehensive review of experimental data for the effects of gaseous Hydrogen Environment Embrittlement (HEE) for several types of metallic materials. Common material screening methods are used to rate the hydrogen degradation of mechanical properties that occur while the material is under an applied stress and exposed to gaseous hydrogen as compared to air or helium, under slow strain rates (SSR) testing. Due to the simplicity and accelerated nature of these tests, the results expressed in terms of HEE index are not intended to necessarily represent true hydrogen service environment for long-term exposure, but rather to provide a practical approach for material screening, which is a useful concept to qualitatively evaluate the severity of

Hydrogen production from high-moisture content biomass in supercritical water

Energy Technology Data Exchange (ETDEWEB)

Antal, M.J. Jr.; Adschiri, T.; Ekbom, T. [Univ. of Hawaii, Honolulu, HI (United States)] [and others

1996-10-01

Most hydrogen is produced by steam reforming methane at elevated pressures. The goal of this research is to develop commercial processes for the catalytic steam reforming of biomass and other organic wastes at high pressures. This approach avoids the high cost of gas compression and takes advantage of the unique properties of water at high pressures. Prior to this year the authors reported the ability of carbon to catalyze the decomposition of biomass and related model compounds in supercritical water. The product gas consists of hydrogen, carbon dioxide, carbon monoxide, methane, and traces of higher hydrocarbons. During the past year the authors have: (a) developed a method to extend the catalyst life, (b) begun studies of the role of the shift reaction, (c) completed studies of carbon dioxide absorption from the product effluent by high pressure water, (d) measured the rate of carbon catalyst gasification in supercritical water, (e) discovered the pumpability of oil-biomass slurries, and (f) completed the design and begun fabrication of a flow reactor that will steam reform whole biomass feedstocks (i.e. sewage sludge) and produce a hydrogen rich synthesis gas at very high pressure (>22 MPa).

System efficiency for two-step metal oxide solar thermochemical hydrogen production – Part 2: Impact of gas heat recuperation and separation temperatures

KAUST Repository

Ehrhart, Brian D.

2016-09-22

The solar-to-hydrogen (STH) efficiency is calculated for various operating conditions for a two-step metal oxide solar thermochemical hydrogen production cycle using cerium(IV) oxide. An inert sweep gas was considered as the O2 removal method. Gas and solid heat recuperation effectiveness values were varied between 0 and 100% in order to determine the limits of the effect of these parameters. The temperature at which the inert gas is separated from oxygen for an open-loop and recycled system is varied. The hydrogen and water separation temperature was also varied and the effect on STH efficiency quantified. This study shows that gas heat recuperation is critical for high efficiency cycles, especially at conditions that require high steam and inert gas flowrates. A key area for future study is identified to be the development of ceramic heat exchangers for high temperature gas-gas heat exchange. Solid heat recuperation is more important at lower oxidation temperatures that favor temperature-swing redox processing, and the relative impact of this heat recuperation is muted if the heat can be used elsewhere in the system. A high separation temperature for the recycled inert gas has been shown to be beneficial, especially for cases of lower gas heat recuperation and increased inert gas flowrates. A higher water/hydrogen separation temperature is beneficial for most gas heat recuperation effectiveness values, though the overall impact on optimal system efficiency is relatively small for the values considered. © 2016 Hydrogen Energy Publications LLC.

Ejection of the Massive Hydrogen-rich Envelope Timed with the Collapse of the Stripped SN 2014C

Energy Technology Data Exchange (ETDEWEB)

Margutti, Raffaella [Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA), Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208 (United States); Kamble, A.; Milisavljevic, D.; Drout, M.; Chakraborti, S.; Kirshner, R.; Parrent, J. T.; Patnaude, D.; Soderberg, A. M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Zapartas, E.; De Mink, S. E. [Anton Pannenkoek Institute for Astronomy, University of Amsterdam, 1090 GE Amsterdam (Netherlands); Chornock, R. [Astrophysical Institute, Department of Physics and Astronomy, 251B Clippinger Lab, Ohio University, Athens, OH 45701 (United States); Risaliti, G. [INAF-Arcetri Astrophysical Observatory, Largo E. Fermi 5, I-50125 Firenze (Italy); Zauderer, B. A. [Center for Cosmology and Particle Physics, New York University, 4 Washington Place, New York, NY 10003 (United States); Bietenholz, M. [Department of Physics and Astronomy, York University, Toronto, ON M3J 1P3 (Canada); Cantiello, M. [Kavli Institute for Theoretical Physics, University of California, Santa Barbara, CA 93106 (United States); Chomiuk, L. [Department of Physics and Astronomy, Michigan State University, East Lansing, MI 48824 (United States); Fong, W. [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Grefenstette, B. [Cahill Center for Astrophysics, 1216 E. California Boulevard, California Institute of Technology, Pasadena, CA 91125 (United States); Guidorzi, C. [University of Ferrara, Department of Physics and Earth Sciences, via Saragat 1, I-44122 Ferrara (Italy); and others

2017-02-01

We present multi-wavelength observations of SN 2014C during the first 500 days. These observations represent the first solid detection of a young extragalactic stripped-envelope SN out to high-energy X-rays ∼40 keV. SN 2014C shows ordinary explosion parameters ( E {sub k} ∼ 1.8 × 10{sup 51} erg and M {sub ej} ∼ 1.7 M{sub ⊙}). However, over an ∼1 year timescale, SN 2014C evolved from an ordinary hydrogen-poor supernova into a strongly interacting, hydrogen-rich supernova, violating the traditional classification scheme of type-I versus type-II SNe. Signatures of the SN shock interaction with a dense medium are observed across the spectrum, from radio to hard X-rays, and revealed the presence of a massive shell of ∼1 M {sub ⊙} of hydrogen-rich material at ∼6 × 10{sup 16} cm. The shell was ejected by the progenitor star in the decades to centuries before collapse. This result challenges current theories of massive star evolution, as it requires a physical mechanism responsible for the ejection of the deepest hydrogen layer of H-poor SN progenitors synchronized with the onset of stellar collapse. Theoretical investigations point at binary interactions and/or instabilities during the last nuclear burning stages as potential triggers of the highly time-dependent mass loss. We constrain these scenarios utilizing the sample of 183 SNe Ib/c with public radio observations. Our analysis identifies SN 2014C-like signatures in ∼10% of SNe. This fraction is reasonably consistent with the expectation from the theory of recent envelope ejection due to binary evolution if the ejected material can survive in the close environment for 10{sup 3}–10{sup 4} years. Alternatively, nuclear burning instabilities extending to core C-burning might play a critical role.

Conversion of Claus plants of Kirkuk-Iraq to produce hydrogen and sulfur

International Nuclear Information System (INIS)

Naman, S.A.; Veziroglu, A.

2009-01-01

'Full text': Hydrogen production from rich sub-quality natural gas (SQNG) is visible technically with assessment of cost, safety and environmental toxicology analysis of hydrogen sulfide, is summarized. There are two Claus plants in Kirkuk-Iraq, converting hydrogen sulfide to elemental sulfur capacity of 2200 ton/day. One of these plants is working with only 400 ton/day and it is an old Claus process. The other is a modified Claus sulfur recovery process with a capacity of 1800 ton/day. Both of these plants operate with low efficiency due to lack of maintenance and the present situation in Iraq. Therefore, the agricultural area around Kirkuk is very polluted by this gas. Two pilot plants have been constructed inside the modified Claus plant in Kirkuk The first one is based on the flow system tube furnace reactor containing mixed Titanium oxide/sulfide with a cold trap for sulfur separation and a bath of 30% dithanolamine to separate and recycle H 2 S from hydrogen. The second pilot plant consists of a thermal diffusion ceramic rod inside a silica column containing Zeolit 5A as a catalyst. This pilot plant also consists of a trap for continuous separation of sulfur and a system for separation of hydrogen from unreacted H 2 S to recycle. The efficiency of conversion of H 2 S to hydrogen and sulfur has been optimized as a function of catalyst type and mixture, temperature of furnace, flow rate of gas and reactor materials until the efficiency reaches more than 97%. The Kirkuk natural gas consists of a mixture of CO 2 10% and H 2 S 12%. We found that these pilot plants were suitable with Cadmium chalcogens catalysts to produce hydrogen, methane, ethane and sulphur, but with lower efficiency than H 2 S decomposition only. Our aim in the second pilot plant, which consists of a silica column, was to supply the heat by solar energy concentrator instead of electricity as our catalyst needs 450 o C. and the solar intensity is about 1000 w/m 2 during the summer. The idea of

Aqueous process for recovering sulfur from hydrogen sulfide-bearing gas

Science.gov (United States)

Basu, Arunabha

2015-05-05

A process for recovering sulfur from a hydrogen sulfide-bearing gas utilizes an aqueous reaction medium, a temperature of about 110-150.degree. C., and a high enough pressure to maintain the aqueous reaction medium in a liquid state. The process reduces material and equipment costs and addresses the environmental disadvantages associated with known processes that rely on high boiling point organic solvents.

Optimization Study of Hydrogen Gas Adsorption on Zig-zag Single-walled Carbon Nanotubes: The Artificial Neural Network Analysis

Science.gov (United States)

Nasruddin; Lestari, M.; Supriyadi; Sholahudin

2018-03-01

The use of hydrogen gas in fuel cell technology has a huge opportunity to be applied in upcoming vehicle technology. One of the most important problems in fuel cell technology is the hydrogen storage. The adsorption of hydrogen in carbon-based materials attracts a lot of attention because of its reliability. This study investigated the adsorption of hydrogen gas in Single-walled Carbon Nano Tubes (SWCNT) with chilarity of (0, 12), (0, 15), and (0, 18) to find the optimum chilarity. Artificial Neural Networks (ANN) can be used to predict the hydrogen storage capacity at different pressure and temperature conditions appropriately, using simulated series of data. The Artificial Neural Network is modeled as a predictor of the hydrogen adsorption capacity which provides solutions to some deficiencies in molecular dynamics (MD) simulations. In a previous study, ANN configurations have been developed for 77k, 233k, and 298k temperatures in hydrogen gas storage. To prepare this prediction, ANN is modeled to find out the configurations that exist in the set of training and validation of specified data selection, the distance between data, and the number of neurons that produce the smallest error. This configuration is needed to make an accurate artificial neural network. The configuration of neural network was then applied to this research. The neural network analysis results show that the best configuration of artificial neural network in hydrogen storage is at 233K temperature i.e. on SWCNT with chilarity of (0.12).

Commercial application of titania-supported hydrodesulfurization catalysts in the production of hydrogen using full-range FCC off-gas

Energy Technology Data Exchange (ETDEWEB)

Wang, Shaohu [SINOPEC Wuhan Branch, Qingshan, Wuhan 430082 (China); Shen, Binglong; Qu, Lianglong [Beijing Haishunde Titanium Catalyst Co. Ltd., A-1 North East-Ring Road, Beijing Economic-Technological Development Area, Beijing 100176 (China)

2004-11-24

This paper provides an alternative for low-cost feed used for on-purpose hydrogen production. Full-range FCC off-gas was applied to steam-reforming process as feed after treating with hydrogenation and hydrodesulfurization catalysts. Commercial run results were reported with novel TiO{sub 2}-supported Mo-based catalysts, T205A-1 and T205. The processes of catalysts loading, sulfidation, start-up and long-term run were described in details. Long-term run showed that TiO{sub 2}-supported Mo catalysts have good low-temperature hydrogenation activity, excellent HDS activity, and outstanding stability. Use of FCC off-gas as feed for hydrogen production is quite promising and will increase margins for refiners today.

Hydrogen Gas Recycling for Energy Efficient Ammonia Recovery in Electrochemical Systems

NARCIS (Netherlands)

Kuntke, Philipp; Rodríguez Arredondo, Mariana; Widyakristi, Laksminarastri; Heijne, ter Annemiek; Sleutels, Tom H.J.A.; Hamelers, Hubertus V.M.; Buisman, Cees J.N.

2017-01-01

Recycling of hydrogen gas (H₂) produced at the cathode to the anode in an electrochemical system allows for energy efficient TAN (Total Ammonia Nitrogen) recovery. Using a H₂ recycling electrochemical system (HRES) we achieved high TAN transport rates at low energy input. At

Reduced-order modellin for high-pressure transient flow of hydrogen-natural gas mixture

Science.gov (United States)

Agaie, Baba G.; Khan, Ilyas; Alshomrani, Ali Saleh; Alqahtani, Aisha M.

2017-05-01

In this paper the transient flow of hydrogen compressed-natural gas (HCNG) mixture which is also referred to as hydrogen-natural gas mixture in a pipeline is numerically computed using the reduced-order modelling technique. The study on transient conditions is important because the pipeline flows are normally in the unsteady state due to the sudden opening and closure of control valves, but most of the existing studies only analyse the flow in the steady-state conditions. The mathematical model consists in a set of non-linear conservation forms of partial differential equations. The objective of this paper is to improve the accuracy in the prediction of the HCNG transient flow parameters using the Reduced-Order Modelling (ROM). The ROM technique has been successfully used in single-gas and aerodynamic flow problems, the gas mixture has not been done using the ROM. The study is based on the velocity change created by the operation of the valves upstream and downstream the pipeline. Results on the flow characteristics, namely the pressure, density, celerity and mass flux are based on variations of the mixing ratio and valve reaction and actuation time; the ROM computational time cost advantage are also presented.

Performance and emission characteristics of a turbocharged CNG engine fueled by hydrogen-enriched compressed natural gas with high hydrogen ratio

Energy Technology Data Exchange (ETDEWEB)

Ma, Fanhua; Wang, Mingyue; Jiang, Long; Chen, Renzhe; Deng, Jiao; Naeve, Nashay; Zhao, Shuli [State Key Laboratory of Automotive Safety and Energy Tsinghua University, Beijing 100084 (China)

2010-06-15

This paper investigates the effect of high hydrogen volumetric ratio of 55% on performance and emission characteristics in a turbocharged lean burn natural gas engine. The experimental data was conducted under various operating conditions including different spark timing, excess air ratio (lambda), and manifold pressure. It is found that the addition of hydrogen at a high volumetric ratio could significantly extend the lean burn limit, improve the engine lean burn ability, decrease burn duration, and yield higher thermal efficiency. The CO, CH{sub 4} emissions were reduced and NO{sub x} emission could be kept an acceptable low level with high hydrogen content under lean burn conditions when ignition timing were optimized. (author)

Integration of Wind Energy, Hydrogen and Natural Gas Pipeline Systems to Meet Community and Transportation Energy Needs: A Parametric Study

Directory of Open Access Journals (Sweden)

Shahryar Garmsiri

2014-04-01

Full Text Available The potential benefits are examined of the “Power-to-Gas” (P2G scheme to utilize excess wind power capacity by generating hydrogen (or potentially methane for use in the natural gas distribution grid. A parametric analysis is used to determine the feasibility and size of systems producing hydrogen that would be injected into the natural gas grid. Specifically, wind farms located in southwestern Ontario, Canada are considered. Infrastructure requirements, wind farm size, pipeline capacity, geographical dispersion, hydrogen production rate, capital and operating costs are used as performance measures. The model takes into account the potential production rate of hydrogen and the rate that it can be injected into the local gas grid. “Straw man” systems are examined, centered on a wind farm size of 100 MW integrating a 16-MW capacity electrolysis system typically producing 4700 kg of hydrogen per day.

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.).

Cooperative catalysis: electron-rich Fe-H complexes and DMAP, a successful "joint venture" for ultrafast hydrogen production.

Science.gov (United States)

Rommel, Susanne; Hettmanczyk, Lara; Klein, Johannes E M N; Plietker, Bernd

2014-08-01

A series of defined iron-hydrogen complexes was prepared in a straightforward one-pot approach. The structure and electronic properties of such complexes were investigated by means of quantum-chemical analysis. These new complexes were then applied in the dehydrogenative silylation of methanol. The complex (dppp)(CO)(NO)FeH showed a remarkable activity with a TOF of more than 600 000 h(-1) of pure hydrogen gas within seconds. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microbial Electrodialysis Cell for Simultaneous Water Desalination and Hydrogen Gas Production

KAUST Repository

Mehanna, Maha

2010-12-15

A new approach to water desalination is to use exoelectrogenic bacteria to generate electrical power from the biodegradation of organic matter, moving charged ions from a middle chamber between two membranes in a type of microbial fuel cell called a microbial desalination cell. Desalination efficiency using this approach is limited by the voltage produced by the bacteria. Here we examine an alternative strategy based on boosting the voltage produced by the bacteria to achieve hydrogen gas evolution from the cathode using a three-chambered system we refer to as a microbial electrodialysis cell (MEDC). We examined the use of the MEDC process using two different initial NaCl concentrations of 5 g/L and 20 g/L. Conductivity in the desalination chamber was reduced by up to 68 ± 3% in a single fed-batch cycle, with electrical energy efficiencies reaching 231 ± 59%, and maximum hydrogen production rates of 0.16 ± 0.05 m3 H2/m3 d obtained at an applied voltage of 0.55 V. The advantage of this system compared to a microbial fuel cell approach is that the potentials between the electrodes can be better controlled, and the hydrogen gas that is produced can be used to recover energy to make the desalination process self-sustaining with respect to electrical power requirements. © 2010 American Chemical Society.

Microbial Electrodialysis Cell for Simultaneous Water Desalination and Hydrogen Gas Production

KAUST Repository

Mehanna, Maha; Kiely, Patrick D.; Call, Douglas F.; Logan, Bruce. E.

2010-01-01

A new approach to water desalination is to use exoelectrogenic bacteria to generate electrical power from the biodegradation of organic matter, moving charged ions from a middle chamber between two membranes in a type of microbial fuel cell called a microbial desalination cell. Desalination efficiency using this approach is limited by the voltage produced by the bacteria. Here we examine an alternative strategy based on boosting the voltage produced by the bacteria to achieve hydrogen gas evolution from the cathode using a three-chambered system we refer to as a microbial electrodialysis cell (MEDC). We examined the use of the MEDC process using two different initial NaCl concentrations of 5 g/L and 20 g/L. Conductivity in the desalination chamber was reduced by up to 68 ± 3% in a single fed-batch cycle, with electrical energy efficiencies reaching 231 ± 59%, and maximum hydrogen production rates of 0.16 ± 0.05 m3 H2/m3 d obtained at an applied voltage of 0.55 V. The advantage of this system compared to a microbial fuel cell approach is that the potentials between the electrodes can be better controlled, and the hydrogen gas that is produced can be used to recover energy to make the desalination process self-sustaining with respect to electrical power requirements. © 2010 American Chemical Society.

Effects of Post-Treatment Hydrogen Gas Inhalation on Uveitis Induced by Endotoxin in Rats.

Science.gov (United States)

Yan, Weiming; Chen, Tao; Long, Pan; Zhang, Zhe; Liu, Qian; Wang, Xiaocheng; An, Jing; Zhang, Zuoming

2018-06-07

BACKGROUND Molecular hydrogen (H2) has been widely reported to have benefiicial effects in diverse animal models and human disease through reduction of oxidative stress and inflammation. The aim of this study was to investigate whether hydrogen gas could ameliorate endotoxin-induced uveitis (EIU) in rats. MATERIAL AND METHODS Male Sprague-Dawley rats were divided into a normal group, a model group, a nitrogen-oxygen (N-O) group, and a hydrogen-oxygen (H-O) group. EIU was induced in rats of the latter 3 groups by injection of lipopolysaccharide (LPS). After that, rats in the N-O group inhaled a gas mixture of 67% N2 and 33% O2, while those in the H-O group inhaled a gas mixture of 67% H2 and 33% O2. All rats were graded according to the signs of uveitis after electroretinography (ERG) examination. Protein concentration in the aqueous humor (AqH) was measured. Furthermore, hematoxylin-eosin staining and immunostaining of anti-ionized calcium-binding adapter molecule 1 (Iba1) in the iris and ciliary body (ICB) were carried out. RESULTS No statistically significant differences existed in the graded score of uveitis and the b-wave peak time in the Dark-adapted 3.0 ERG among the model, N-O, and H-O groups (P>0.05), while rats of the H-O group showed a lower concentration of AqH protein than that of the model or N-O group (P0.05), while the activation of microglia cells in the H-O group was somewhat reduced (Ptreatment hydrogen gas inhalation did not ameliorate the clinical signs, or reduce the infiltrating cells of EIU. However, it inhibited the elevation of protein in the AqH and reduced the microglia activation.

Ultrafine hydrogen storage powders

Science.gov (United States)

Anderson, Iver E.; Ellis, Timothy W.; Pecharsky, Vitalij K.; Ting, Jason; Terpstra, Robert; Bowman, Robert C.; Witham, Charles K.; Fultz, Brent T.; Bugga, Ratnakumar V.

2000-06-13

A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage material, such, for example, LaNi.sub.5 and other AB.sub.5 type materials and AB.sub.5+x materials, where x is from about -2.5 to about +2.5, including x=0, and the melt is gas atomized under conditions of melt temperature and atomizing gas pressure to form generally spherical powder particles. The hydrogen storage powder exhibits improved chemcial homogeneity as a result of rapid solidfication from the melt and small particle size that is more resistant to microcracking during hydrogen absorption/desorption cycling. A hydrogen storage component, such as an electrode for a battery or electrochemical fuel cell, made from the gas atomized hydrogen storage material is resistant to hydrogen degradation upon hydrogen absorption/desorption that occurs for example, during charging/discharging of a battery. Such hydrogen storage components can be made by consolidating and optionally sintering the gas atomized hydrogen storage powder or alternately by shaping the gas atomized powder and a suitable binder to a desired configuration in a mold or die.

Hydrogen storage materials discovery via high throughput ball milling and gas sorption.

Science.gov (United States)

Li, Bin; Kaye, Steven S; Riley, Conor; Greenberg, Doron; Galang, Daniel; Bailey, Mark S

2012-06-11

The lack of a high capacity hydrogen storage material is a major barrier to the implementation of the hydrogen economy. To accelerate discovery of such materials, we have developed a high-throughput workflow for screening of hydrogen storage materials in which candidate materials are synthesized and characterized via highly parallel ball mills and volumetric gas sorption instruments, respectively. The workflow was used to identify mixed imides with significantly enhanced absorption rates relative to Li2Mg(NH)2. The most promising material, 2LiNH2:MgH2 + 5 atom % LiBH4 + 0.5 atom % La, exhibits the best balance of absorption rate, capacity, and cycle-life, absorbing >4 wt % H2 in 1 h at 120 °C after 11 absorption-desorption cycles.

Glitters of warm H2 in cold diffuse molecular gas

NARCIS (Netherlands)

Falgarone, Edith; Beichman, Chaz; Boulanger, Francois; Combes, Francoise; Gry, Cecile; Helou, Georges; Laureijs, Rene; Pineau Des Forets, Guillaume; Valentijn, Edwin; Verstraete, Laurent

2004-01-01

Cold molecular hydrogen, a possibly dominant gas fraction in galaxies, does not radiate due to the symmetry and small moment of inertia of the molecule. The only tracers of cold H2, the rotational lines of CO and dust thermal emission operate only in metal-rich environments. By detecting the lowest

Polycyclic aromatic hydrocarbons and molecular hydrogen in oxygen-rich planetary nebulae: the case of NGC 6720.

Science.gov (United States)

Cox, N L J; Pilleri, P; Berné, O; Cernicharo, J; Joblin, C

2016-02-11

Evolved stars are primary sources for the formation of polycyclic aromatic hydrocarbons (PAHs) and dust grains. Their circumstellar chemistry is usually designated as either oxygen-rich or carbon-rich, although dual-dust chemistry objects, whose infrared spectra reveal both silicate- and carbon-dust features, are also known. The exact origin and nature of this dual-dust chemistry is not yet understood. Spitzer -IRS mid-infrared spectroscopic imaging of the nearby, oxygen-rich planetary nebula NGC 6720 reveals the presence of the 11.3 μ m aromatic (PAH) emission band. It is attributed to emission from neutral PAHs, since no band is observed in the 7-8 μ m range. The spatial distribution of PAHs is found to closely follow that of the warm clumpy molecular hydrogen emission. Emission from both neutral PAHs and warm H 2 is likely to arise from photo-dissociation regions associated with dense knots that are located within the main ring. The presence of PAHs together with the previously derived high abundance of free carbon (relative to CO) suggest that the local conditions in an oxygen-rich environment can also become conducive to in-situ formation of large carbonaceous molecules, such as PAHs, via a bottom-up chemical pathway. In this scenario, the same stellar source can enrich the interstellar medium with both oxygen-rich dust and large carbonaceous molecules.

Law proposal aiming at imposing the domestic consumption tax to the natural gas used for hydrogen generation for petroleum refining purposes

International Nuclear Information System (INIS)

2009-04-01

In France, natural gas benefits from tax exemptions in several situations and in particular when used as raw material for hydrogen generation, which in turn, is used for crude oil refining and fuels generation. However, crude oil is cheaper when it is heavier but more hydrogen, and thus more natural gas, is needed to refine it and more CO 2 is released in the atmosphere. Therefore, refining cheap crude oil increases the refining margins of oil companies but their environmental impact as well. The aim of this law proposal is to impose the domestic consumption tax to natural gas when used in oil refining processes in order to finance the development of the renewable hydrogen industry through the creation of a High Council of Hydrogen Industry. This High Council would be in charge of promoting the development of renewable hydrogen production facilities and distribution circuits, of hydrogen-fueled vehicles, and of fuel cells. (J.S.)

Reduced gas seepages in ophiolitic complexes: Evidences for multiple origins of the H2-CH4-N2 gas mixtures

Science.gov (United States)

Vacquand, Christèle; Deville, Eric; Beaumont, Valérie; Guyot, François; Sissmann, Olivier; Pillot, Daniel; Arcilla, Carlo; Prinzhofer, Alain

2018-02-01

This paper proposes a comparative study of reduced gas seepages occurring in ultrabasic to basic rocks outcropping in ophiolitic complexes based on the study of seepages from Oman, the Philippines, Turkey and New Caledonia. This study is based on analyses of the gas chemical composition, noble gases contents, stable isotopes of carbon, hydrogen and nitrogen. These seepages are mostly made of mixtures of three main components which are H2, CH4 and N2 in various proportions. The relative contents of the three main gas components show 4 distinct types of gas mixtures (H2-rich, N2-rich, N2-H2-CH4 and H2-CH4). These types are interpreted as reflecting different zones of gas generation within or below the ophiolitic complexes. In the H2-rich type, associated noble gases display signatures close to the value of air. In addition to the atmospheric component, mantle and crustal contributions are present in the N2-rich, N2-H2-CH4 and H2-CH4 types. H2-bearing gases are either associated with ultra-basic (pH 10-12) spring waters or they seep directly in fracture systems from the ophiolitic rocks. In ophiolitic contexts, ultrabasic rocks provide an adequate environment with available Fe2+ and alkaline conditions that favor H2 production. CH4 is produced either directly by reaction of dissolved CO2 with basic-ultrabasic rocks during the serpentinization process or in a second step by H2-CO2 interaction. H2 is present in the gas when no more carbon is available in the system to generate CH4. The N2-rich type is notably associated with relatively high contents of crustal 4He and in this gas type N2 is interpreted as issued mainly from sediments located below the ophiolitic units.

Beneficial effects of hydrogen-rich saline on early burn-wound progression in rats.

Directory of Open Access Journals (Sweden)

Song Xue Guo

Full Text Available Deep burn wounds undergo a dynamic process known as wound progression that results in a deepening and extension of the initial burn area. The zone of stasis is more likely to develop more severe during wound progression in the presence of hypoperfusion. Hydrogen has been reported to alleviate injury triggered by ischaemia/reperfusion and burns in various organs by selectively quenching oxygen free radicals. The aim of this study was to investigate the possible protective effects of hydrogen against early burn-wound progression.Deep-burn models were established through contact with a boiled, rectangular, brass comb for 20 s. Fifty-six Sprague-Dawley rats were randomly divided into sham, burn plus saline, and burn plus hydrogen-rich saline (HS groups with sacrifice and analysis at various time windows (6 h, 24 h, 48 h post burn. Indexes of oxidative stress, apoptosis and autophagy were measured in each group. The zone of stasis was evaluated using immunofluorescence staining, ELISA, and Western blot to explore the underlying effects and mechanisms post burn.The burn-induced increase in malondialdehyde was markedly reduced with HS, while the activities of endogenous antioxidant enzymes were significantly increased. Moreover, HS treatment attenuated increases in apoptosis and autophagy postburn in wounds, according to the TUNEL staining results and the expression analysis of Bax, Bcl-2, caspase-3, Beclin-1 and Atg-5 proteins. Additionally, HS lowered the level of myeloperoxidase and expression of TNF-α, IL-1β, and IL-6 in the zone of stasis while augmenting IL-10. The elevated levels of Akt phosphorylation and NF-κB p65 expression post burn were also downregulated by HS management.Hydrogen can attenuate early wound progression following deep burn injury. The beneficial effect of hydrogen was mediated by attenuating oxidative stress, which inhibited apoptosis and inflammation, and the Akt/NF-κB signalling pathway may be involved in regulating the

Hydrogen production by steam reforming of liquefied natural gas over a nickel catalyst supported on mesoporous alumina xerogel

Science.gov (United States)

Seo, Jeong Gil; Youn, Min Hye; Cho, Kyung Min; Park, Sunyoung; Song, In Kyu

Mesoporous alumina xerogel (A-SG) is prepared by a sol-gel method for use as a support for a nickel catalyst. The Ni/A-SG catalyst is then prepared by an impregnation method, and is applied to hydrogen production by steam reforming of liquefied natural gas (LNG). The effect of the mesoporous alumina xerogel support on the catalytic performance of Ni/A-SG catalyst is investigated. For the purpose of comparison, a nickel catalyst supported on commercial alumina (A-C) is also prepared by an impregnation method (Ni/A-C). Both the hydroxyl-rich surface and the electron-deficient sites of the A-SG support enhance the dispersion of the nickel species on the support during the calcination step. The formation of the surface nickel aluminate phase in the Ni/A-SG catalyst remarkably increases the reducibility and stability of the catalyst. Furthermore, the high-surface area and the well-developed mesoporosity of the Ni/A-SG catalyst enhance the gasification of surface hydrocarbons that are adsorbed in the reaction. In the steam reforming of LNG, the Ni/A-SG catalyst exhibits a better catalytic performance than the Ni/A-C catalyst in terms of LNG conversion and hydrogen production. Moreover, the Ni/A-SG catalyst shows strong resistance toward catalyst deactivation.

γ-irradiation effect on gas diffusion in polymer films. Part I : Hydrogen diffusion through mylar film

International Nuclear Information System (INIS)

Rao, K.A.; Pushpa, K.K.; Iyer, R.M.

1980-01-01

γ-irradiation of polymers results in further crosslinking in the polymer or breakdown of the polymer or a combination of both these phenomena depending on the type of polymer, the dose as well as the environment in which irradiation is carried out. The gas diffusion through polymer films is expected to vary depending on these changes. With a view to A evaluate the feasibility of effecting selective diffusion of specific gases and also to correlate the change in diffusion rates with the polymer characteristics these studies have been initiated. Hydrogen diffusion through mylar film γ-irradiated under varying conditions upto a dose of approximately 50 Mrads is reported in this paper. The results indicate negligible change in hydrogen diffusion rates on γ-irradiation. However, γ-irradiation induced crosslinking of acrylic acid on Mylar reduced the hydrogen diffusion rate. The hydrogen diffusion studies may also be useful in finding the glass transition temperature of polymer films as is apparent from the gas diffusion curves. (author)

A novel gas separation integrated membrane bioreactor to evaluate the impact of self-generated biogas recycling on continuous hydrogen fermentation

International Nuclear Information System (INIS)

Bakonyi, Péter; Buitrón, Germán; Valdez-Vazquez, Idania; Nemestóthy, Nándor; Bélafi-Bakó, Katalin

2017-01-01

Highlights: • A Gas Separation Membrane Bioreactor was designed to improve H_2 production. • Headspace gas after enrichment by PDMS membranes was used for reactor sparging. • Stripping the bioreactor with a CO_2-enriched gas enhanced the H_2 fermentation. - Abstract: A Gas Separation Membrane Bioreactor (GSMBR) by integrating membrane technology with a continuous biohydrogen fermenter was designed. The feasibility of this novel configuration for the improvement of hydrogen production capacity was tested by stripping the fermentation liquor with CO_2- and H_2-enriched gases, obtained directly from the bioreactor headspace. The results indicated that sparging the bioreactor with the CO_2-concentrated fraction of the membrane separation unit (consisting of two PDMS modules) enhanced the steady-state H_2 productivity (8.9–9.2 L H_2/L-d) compared to the membrane-less control CSTR to be characterized with 6.96–7.35 L H_2/L-d values. On the other hand, purging with the H_2-rich gas strongly depressed the achievable productivity (2.7–3.03 L H_2/L-d). Microbial community structure and soluble metabolic products were monitored to assess the GSMBR behavior. The study demonstrated that stripping the bioH_2 fermenter with its own, self-generated atmosphere after adjusting its composition (to higher CO_2-content) can be a promising way to intensify dark fermentative H_2 evolution.

Hydrogen Oxidation on Gas Diffusion Electrodes for Phosphoric Acid Fuel Cells in the Presence of Carbon Monoxide and Oxygen

DEFF Research Database (Denmark)

Gang, Xiao; Li, Qingfeng; Hjuler, Hans Aage

1995-01-01

Hydrogen oxidation has been studied on a carbon-supported platinum gas diffusion electrode in a phosphoric acidelectrolyte in the presence of carbon monoxide and oxygen in the feed gas. The poisoning effect of carbon monoxide presentin the feed gas was measured in the temperature range from 80...... to 150°C. It was found that throughout the temperaturerange, the potential loss due to the CO poisoning can be reduced to a great extent by the injection of small amounts ofgaseous oxygen into the hydrogen gas containing carbon monoxide. By adding 5 volume percent (v/o) oxygen, an almost...

Radcalc for windows benchmark study: A comparison of software results with Rocky Flats hydrogen gas generation data

International Nuclear Information System (INIS)

MCFADDEN, J.G.

1999-01-01

Radcalc for Windows Version 2.01 is a user-friendly software program developed by Waste Management Federal Services, Inc., Northwest Operations for the U.S. Department of Energy (McFadden et al. 1998). It is used for transportation and packaging applications in the shipment of radioactive waste materials. Among its applications are the classification of waste per the US. Department of Transportation regulations, the calculation of decay heat and daughter products, and the calculation of the radiolytic production of hydrogen gas. The Radcalc program has been extensively tested and validated (Green et al. 1995, McFadden et al. 1998) by comparison of each Radcalc algorithm to hand calculations. An opportunity to benchmark Radcalc hydrogen gas generation calculations to experimental data arose when the Rocky Flats Environmental Technology Site (RFETS) Residue Stabilization Program collected hydrogen gas generation data to determine compliance with requirements for shipment of waste in the TRUPACT-II (Schierloh 1998). The residue/waste drums tested at RFETS contain contaminated, solid, inorganic materials in polyethylene bags. The contamination is predominantly due to plutonium and americium isotopes. The information provided by Schierloh (1 998) of RFETS includes decay heat, hydrogen gas generation rates, calculated G eff values, and waste material type, making the experimental data ideal for benchmarking Radcalc. The following sections discuss the RFETS data and the Radcalc cases modeled with the data. Results are tabulated and also provided graphically

Hydrogen production from biomass pyrolysis gas via high temperature steam reforming process

International Nuclear Information System (INIS)

Wongchang, Thawatchai; Patumsawad, Suthum

2010-01-01

Full text: The aim of this work has been undertaken as part of the design of continuous hydrogen production using the high temperature steam reforming process. The steady-state test condition was carried out using syngas from biomass pyrolysis, whilst operating at high temperatures between 600 and 1200 degree Celsius. The main reformer operating parameters (e.g. temperature, resident time and steam to biomass ratio (S/B)) have been examined in order to optimize the performance of the reformer. The operating temperature is a key factor in determining the extent to which hydrogen production is increased at higher temperatures (900 -1200 degree Celsius) whilst maintaining the same as resident time and S/B ratio. The effects of exhaust gas composition on heating value were also investigated. The steam reforming process produced methane (CH 4 ) and ethylene (C 2 H 4 ) between 600 to 800 degree Celsius and enhanced production ethane (C 2 H 6 ) at 700 degree Celsius. However carbon monoxide (CO) emission was slightly increased for higher temperatures all conditions. The results show that the use of biomass pyrolysis gas can produce higher hydrogen production from high temperature steam reforming. In addition the increasing reformer efficiency needs to be optimized for different operating conditions. (author)

Preliminary design analysis of hot gas ducts and a intermediate heat exchanger for the nuclear hydrogen reactor

International Nuclear Information System (INIS)

Song, K. N.; Kim, Y. W.

2008-01-01

Korea Atomic Energy Research Institute (KAERI) is in the process of carrying out a nuclear hydrogen system by considering the indirect cycle gas cooled reactors that produce heat at temperatures in the order of 950 .deg. C. Primary and secondary hot gas ducts with coaxial double tubes and are key components connecting a reactor pressure vessel and a intermediate heat exchanger for the nuclear hydrogen system. In this study, preliminary design analyses on the hot gas ducts and the intermediate heat exchanger were carried out. These preliminary design activities include a preliminary design on the geometric dimensions, a preliminary strength evaluation, thermal sizing, and an appropriate material selection

Hydrogen from biomass gas steam reforming for low temperature fuel cell: energy and exergy analysis

Directory of Open Access Journals (Sweden)

A. Sordi

2009-03-01

Full Text Available This work presents a method to analyze hydrogen production by biomass gasification, as well as electric power generation in small scale fuel cells. The proposed methodology is the thermodynamic modeling of a reaction system for the conversion of methane and carbon monoxide (steam reforming, as well as the energy balance of gaseous flow purification in PSA (Pressure Swing Adsorption is used with eight types of gasification gases in this study. The electric power is generated by electrochemical hydrogen conversion in fuel cell type PEMFC (Proton Exchange Membrane Fuel Cell. Energy and exergy analyses are applied to evaluate the performance of the system model. The simulation demonstrates that hydrogen production varies with the operation temperature of the reforming reactor and with the composition of the gas mixture. The maximum H2 mole fraction (0.6-0.64 mol.mol-1 and exergetic efficiency of 91- 92.5% for the reforming reactor are achieved when gas mixtures of higher quality such as: GGAS2, GGAS4 and GGAS5 are used. The use of those gas mixtures for electric power generation results in lower irreversibility and higher exergetic efficiency of 30-30.5%.

40 CFR 266.107 - Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions.

Science.gov (United States)

2010-07-01

... 40 Protection of Environment 26 2010-07-01 2010-07-01 false Standards to control hydrogen chloride... WASTES AND SPECIFIC TYPES OF HAZARDOUS WASTE MANAGEMENT FACILITIES Hazardous Waste Burned in Boilers and Industrial Furnaces § 266.107 Standards to control hydrogen chloride (HCl) and chlorine gas (Cl2) emissions...

Thermodynamic analyses of hydrogen production from sub-quality natural gas

Energy Technology Data Exchange (ETDEWEB)

Huang, Cunping; T-Raissi, Ali [Florida Solar Energy Center, University of Central Florida, 1679 Clearlake Road, Cocoa, FL 32922-5403 (United States)

2007-01-01

Part I of this paper analyzed sub-quality natural gas (SQNG) pyrolysis and autothermal pyrolysis. Production of hydrogen via direct thermolysis of SQNGs produces only 2mol of hydrogen and 1mol of carbon per mole of methane (CH{sub 4}). Steam reforming of SQNG (SRSQNG) could become a more effective approach because the processes produce two more moles of hydrogen via water splitting. A Gibbs reactor unit operation in the AspenPlus(TM) chemical process simulator was employed to accomplish equilibrium calculations for the SQNG+H{sub 2}O and SQNG+H{sub 2}O+O{sub 2} systems. The results indicate that water and oxygen inlet flow rates do not significantly affect the decomposition of hydrogen sulfide (H{sub 2}S) at temperatures lower than 1000{sup o}C. The major co-product of the processes is carbonyl sulfide (COS) while sulfur dimer (S{sub 2}) and carbon disulfide (CS{sub 2}) are minor by-products within this temperature range. At higher temperatures (>1300{sup o}C), CS{sub 2} and S{sub 2} become major co-products. No sulfur dioxide (SO{sub 2}) or sulfur trioxide (SO{sub 3}) is formed during either SRSQNG or autothermal SRSQNG processes, indicating that no environmentally harmful acidic gases are generated. (author)

Analysis of trace levels of impurities and hydrogen isotopes in helium purge gas using gas chromatography for tritium extraction system of an Indian lead lithium ceramic breeder test blanket module.

Science.gov (United States)

Devi, V Gayathri; Sircar, Amit; Yadav, Deepak; Parmar, Jayraj

2018-01-12

In the fusion fuel cycle, the accurate analysis and understanding of the chemical composition of any gas mixture is of great importance for the efficient design of a tritium extraction and purification system or any tritium handling system. Methods like laser Raman spectroscopy and gas chromatography with thermal conductivity detector have been considered for hydrogen isotopes analyses in fuel cycles. Gas chromatography with a cryogenic separation column has been used for the analysis of hydrogen isotopes gas mixtures in general due to its high reliability and ease of operation. Hydrogen isotopes gas mixture analysis with cryogenic columns has been reported earlier using different column materials for percentage level composition. In the present work, trace levels of hydrogen isotopes (∼100 ppm of H 2 and D 2 ) have been analyzed with a Zeolite 5A and a modified γ-Al 2 O 3 column. Impurities in He gas (∼10 ppm of H 2 , O 2 , and N 2 ) have been analyzed using a Zeolite 13-X column. Gas chromatography with discharge ionization detection has been utilized for this purpose. The results of these experiments suggest that the columns developed were able to separate ppm levels of the desired components with a small response time (<6 min) and good resolution in both cases. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Development of a fermentation-based process for biomass conversion to hydrogen gas

NARCIS (Netherlands)

Claassen, P.A.M.; Vrije, de G.J.; Urbaniec, K.; Grabarczyk, R.

2010-01-01

The production of hydrogen gas from biomass to meet the foreseen demand arising from the expected introduction of fuel cells is envisaged. Apart from the well-known gasification method, fermentative conversion can also be applied for this purpose. Two options of the latter method, that is,

Tritium assay in hydrogen gas by proportional counter with magnetic tape recording

International Nuclear Information System (INIS)

Grabczak, J.

1982-03-01

Analytical procedure is discussed concerning routine tritium activity determination in water samples based on hydrogen production from the water sample and radioactivity measurement by gas proportional counting. The method was found to be fully comparable to the widely adopted technique of liquid scintillation counting with electrolytic enrichment

Non-catalytic plasma-arc reforming of natural gas with carbon dioxide as the oxidizing agent for the production of synthesis gas or hydrogen

OpenAIRE

Blom, P.W.E.; Basson, G.W.

2013-01-01

The world’s energy consumption is increasing constantly due to the growing population of the world. The increasing energy consumption has a negative effect on the fossil fuel reserves of the world. Hydrogen has the potential to provide energy for all our needs by making use of fossil fuel such as natural gas and nuclear-based electricity. Hydrogen can be produced by reforming methane with carbon dioxide as the oxidizing agent. Hydrogen can be produced in a Plasma-arc reforming ...

The Use of Gas Chromatography for Biogas Analysis

Science.gov (United States)

Andersen, Amanda; Seeley, John; Aurandt, Jennifer

2010-04-01

Energy from natural gas accounts for 24 percent of energy consumed in the US. Natural gas is a robust form of energy which is rich in methane content and is low in impurities. This quality suggests that it is a very clean and safe gas; it can be used in providing heat, a source for cooking, and in powering vehicles. The downside is that it is a non-renewable resource. On the contrary, methane rich gas that is produced by the breakdown of organic material in an anaerobic environment, called biogas, is a renewable energy source. This research focuses on the gas analysis portion of the creation of the anaerobic digestion and verification laboratory where content and forensic analysis of biogas is performed. Gas Chromatography is implemented as the optimal analytical tool for quantifying the components of the biogas including methane, carbon dioxide, hydrogen sulfide and siloxanes. In addition, the problems associated with the undesirable components are discussed. Anaerobic digestion of primary sludge has consistently produced about 55 percent methane; future goals of this research include studying different substrates to increase the methane yield and decrease levels of impurities in the gas.

Reduced gas seepages in serpentinized peridotite complexes: Evidences for multiple origins of the H2-CH4-N2 gas mixtures

Science.gov (United States)

Deville, E.; Vacquand, C.; Beaumont, V.; Francois, G.; Sissmann, O.; Pillot, D.; Arcilla, C. A.; Prinzhofer, A.

2017-12-01

A comparative study of reduced gas seepages associated to serpentinized ultrabasic rocks was conducted in the ophiolitic complexes of Oman, the Philippines, Turkey and New Caledonia. This study is based on analyzes of the gas chemical composition, noble gases contents, and stable isotopes of carbon, hydrogen and nitrogen. These gas seepages are mostly made of mixtures of three main components which are H2, CH4 and N2 in various proportions. The relative contents of the three main gas components show 4 distinct families of gas mixtures (H2-rich, N2-rich, N2-H2-CH4 and H2-CH4). These families are interpreted as reflecting different zones of gas generation within or below the ophiolitic complexes. In the H2-rich family associated noble gases display signatures close to the value of air. In addition to the atmospheric component, mantle and crustal contributions are present in the N2-rich, N2-H2-CH4 and H2-CH4 families. H2-bearing gases are either associated to ultra-basic (pH 10-12) spring waters or they seep directly in fracture systems from the ophiolitic rocks. In ophiolitic contexts, ultrabasic rocks provide an adequate environment with available Fe2+ and high pH conditions that favor H2 production. CH4 is produced either directly by reaction of dissolved CO2 with basic-ultrabasic rocks during the serpentinization process or in a second step by H2-CO2 interaction. H2 is present in the gas when no more carbon is available in the system to generate CH4 (conditions of strong carbon restriction). The N2-rich family is associated with relatively high contents of crustal 4He. In this family N2 is interpreted as issued mainly from sediments located below the ophiolitic units.

Hydrogen Gas Retention and Release from WTP Vessels: Summary of Preliminary Studies

Energy Technology Data Exchange (ETDEWEB)

Gauglitz, Phillip A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bontha, Jagannadha R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Daniel, Richard C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mahoney, Lenna A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Rassat, Scot D. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wells, Beric E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bao, Jie [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Boeringa, Gregory K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Buchmiller, William C. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Burns, Carolyn A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chun, Jaehun [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Karri, Naveen K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Li, Huidong [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Tran, Diana N. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-07-01

The Hanford Waste Treatment and Immobilization Plant (WTP) is currently being designed and constructed to pretreat and vitrify a large portion of the waste in the 177 underground waste storage tanks at the Hanford Site. A number of technical issues related to the design of the pretreatment facility (PTF) of the WTP have been identified. These issues must be resolved prior to the U.S. Department of Energy (DOE) Office of River Protection (ORP) reaching a decision to proceed with engineering, procurement, and construction activities for the PTF. One of the issues is Technical Issue T1 - Hydrogen Gas Release from Vessels (hereafter referred to as T1). The focus of T1 is identifying controls for hydrogen release and completing any testing required to close the technical issue. In advance of selecting specific controls for hydrogen gas safety, a number of preliminary technical studies were initiated to support anticipated future testing and to improve the understanding of hydrogen gas generation, retention, and release within PTF vessels. These activities supported the development of a plan defining an overall strategy and approach for addressing T1 and achieving technical endpoints identified for T1. Preliminary studies also supported the development of a test plan for conducting testing and analysis to support closing T1. Both of these plans were developed in advance of selecting specific controls, and in the course of working on T1 it was decided that the testing and analysis identified in the test plan were not immediately needed. However, planning activities and preliminary studies led to significant technical progress in a number of areas. This report summarizes the progress to date from the preliminary technical studies. The technical results in this report should not be used for WTP design or safety and hazards analyses and technical results are marked with the following statement: “Preliminary Technical Results for Planning – Not to be used for WTP Design

Microbial Electrolysis Cells for High Yield Hydrogen Gas Production from Organic Matter

NARCIS (Netherlands)

Logan, B.E.; Call, D.; Cheng, S.; Hamelers, H.V.M.; Sleutels, T.H.J.A.; Jeremiasse, A.W.; Rozendal, R.A.

2008-01-01

The use of electrochemically active bacteria to break down organic matter, combined with the addition of a small voltage (>0.2 V in practice) in specially designed microbial electrolysis cells (MECs), can result in a high yield of hydrogen gas. While microbial electrolysis was invented only a few

Hydrogen enriched compressed natural gas (HCNG: A futuristic fuel for internal combustion engines

Directory of Open Access Journals (Sweden)

Nanthagopal Kasianantham

2011-01-01

Full Text Available Air pollution is fast becoming a serious global problem with increasing population and its subsequent demands. This has resulted in increased usage of hydrogen as fuel for internal combustion engines. Hydrogen resources are vast and it is considered as one of the most promising fuel for automotive sector. As the required hydrogen infrastructure and refueling stations are not meeting the demand, widespread introduction of hydrogen vehicles is not possible in the near future. One of the solutions for this hurdle is to blend hydrogen with methane. Such types of blends take benefit of the unique combustion properties of hydrogen and at the same time reduce the demand for pure hydrogen. Enriching natural gas with hydrogen could be a potential alternative to common hydrocarbon fuels for internal combustion engine applications. Many researchers are working on this for the last few years and work is now focused on how to use this kind of fuel to its maximum extent. This technical note is an assessment of HCNG usage in case of internal combustion engines. Several examples and their salient features have been discussed. Finally, overall effects of hydrogen addition on an engine fueled with HCNG under various conditions are illustrated. In addition, the scope and challenges being faced in this area of research are clearly described.

Achievement report on research and development in the Sunshine Project in fiscal 1976. Comprehensive discussion on hydrogen utilizing subsystems and research on peripheral technologies (Research related to hydrogen gas turbines); 1976 nendo suiso riyo subsystem no sogoteki kento to shuhen gijutsu ni kansuru kenkyu. Suiso gas turbine ni kansuru kenkyu

Energy Technology Data Exchange (ETDEWEB)

NONE

1977-03-01

This paper describes development of hydrogen gas turbines from among the comprehensive discussions on hydrogen utilizing subsystems. Hydrogen and oxygen gas turbine cycle has varying optimal conditions of plant efficiency depending on fuel patterns. The regenerative cycle may have the turbine inlet temperature at about 1,000 degrees C. The inlet pressure would be ten and odds atmospheric pressure. It is better to keep the inlet temperature higher in order to obtain high specific power. Reduction of power generation cost in using this plant requires that construction cost be decreased, and the specific power be increased if the plant efficiency (in other words, running cost) is assumed constant. Further development is required on technologies to use higher temperatures and pressures. For that purpose, discussions should be given on material development, structural design, and inspection. Hydrogen gas turbines, which present low pollution depending on combustion methods, have great significance for such social problem as environmental contamination. In terms of economy, since hydrogen gas turbines depend on efficiency and fuel unit cost, the evaluation thereon may vary depending on how well the regenerative gas turbines have been established, in addition to future change in hydrogen price and the technologies to use higher temperatures and pressures. (NEDO)

ELECTROCHEMICAL SEPARATION AND CONCENTRATION OF HYDROGEN SULFIDE FROM GAS MIXTURES

Science.gov (United States)

Winnick, Jack; Sather, Norman F.; Huang, Hann S.

1984-10-30

A method of removing sulfur oxides of H.sub.2 S from high temperature gas mixtures (150.degree.-1000.degree. C.) is the subject of the present invention. An electrochemical cell is employed. The cell is provided with inert electrodes and an electrolyte which will provide anions compatible with the sulfur containing anions formed at the anode. The electrolyte is also selected to provide inert stable cations at the temperatures encountered. The gas mixture is passed by the cathode where the sulfur gases are converted to SO.sub.4 -- or, in the case of H.sub.2 S, to S--. The anions migrate to the anode where they are converted to a stable gaseous form at much greater concentration levels (>10X). Current flow may be effected by utilizing an external source of electrical energy or by passing a reducing gas such as hydrogen past the anode.

Stripped-envelope supernova SN 2004dk is now interacting with hydrogen-rich circumstellar material

Science.gov (United States)

Mauerhan, Jon C.; Filippenko, Alexei V.; Zheng, WeiKang; Brink, Thomas; Graham, Melissa L.; Shivvers, Isaac; Clubb, Kelsey

2018-05-01

The dominant mechanism and time scales over which stripped-envelope supernovae (SNe) progenitor stars shed their hydrogen envelopes are uncertain. Observations of Type Ib and Ic SNe at late phases could reveal the optical signatures of interaction with distant circumstellar material (CSM) providing important clues on the origin of the necessary pre-SN mass loss. We report deep late-time optical spectroscopy of the Type Ib explosion SN 2004dk 4684 days (13 years) after discovery. We detect strong Hα emission with an intermediate line width of ˜400 km s-1 and luminosity ˜2.5 × 1039 erg s-1, signaling that the SN blast wave has caught up with the hydrogen-rich CSM lost by the progenitor system. The line luminosity is the highest ever reported for a SN at this late stage. Prominent emission features of He I, Fe, and Ca are also detected. The spectral characteristics are consistent with CSM energized by the forward shock, and resemble the late-time spectra of the persistently interacting Type IIn SNe 2005ip and 1988Z. We suggest that the onset of interaction with H-rich CSM was associated with a previously reported radio rebrightening at ˜1700 days. The data indicate that the mode of pre-SN mass loss was a relatively slow dense wind that persisted millennia before the SN, followed by a short-lived Wolf-Rayet phase that preceded core-collapse and created a cavity within an extended distribution of CSM. We also present new spectra of SNe 2014C, PTF11iqb, and 2009ip, all of which also exhibit continued interaction with extended CSM distributions.

Pressure of a partially ionized hydrogen gas : numerical results from exact low temperature expansions

OpenAIRE

Alastuey , Angel; Ballenegger , Vincent

2010-01-01

8 pages; International audience; We consider a partially ionized hydrogen gas at low densities, where it reduces almost to an ideal mixture made with hydrogen atoms in their ground-state, ionized protons and ionized electrons. By performing systematic low-temperature expansions within the physical picture, in which the system is described as a quantum electron-proton plasma interacting via the Coulomb potential, exact formulae for the first five leading corrections to the ideal Saha equation ...

Gas-phase Hydrogenation of Crotonaldehyde Over Nickel-on-Kieselguhr Catalyst Pellets

International Nuclear Information System (INIS)

Uraz, C.; Atalay, F.; Atalay, S.

2001-01-01

Gas phase catalytic hydrogenation of crotonaldehyde to η-butanol was investigated. A nickel based commercial catalyst produced by Harshaw was used at constant temperatures ranging from 160 to 210deg; at pressures of 1.5, 2 , and 2.5 atm and at different crotonaldehyde to hydrogen feed ratios changing from 0.134 to 0.226. The conversion of crotonaldehyde at different operating conditions were determined and the reaction rates were calculated . The experimental results were fitted to ten langmuir-Hinshelwood/ Eley Rideal type models in addition to a homogeneous kinetics modal and the best modal was identified. The effects of external and internal mass transfer resistances were found to be negligible .(authors) refs 28., 2 figs , 4 tabs

Numerical investigation on the effects of natural gas and hydrogen blends on engine combustion

Energy Technology Data Exchange (ETDEWEB)

Morrone, Biagio; Unich, Andrea [Dipartimento di Ingegneria Aerospaziale e Meccanica (DIAM), Seconda Universita degli Studi di Napoli via Roma 29, 81031 Aversa (CE) (Italy)

2009-05-15

The use of hydrogen blended with natural gas is a viable alternative to pure fossil fuels because of the expected reduction of the total pollutant emissions and increase of efficiency. These blends offer a valid opportunity for tackling sustainable transportation, in view of the future stringent emission limits for road vehicles. The aim of the present paper is the investigation of the performance of internal combustion engines fuelled by such blends. A numerical investigation on the characteristics of natural gas-hydrogen blends as well as their effect on engine performance is carried out. The activity is focused on the influence of such blends on flame propagation speed. Combustion pattern modelling allows the comparison of engine brake efficiency and power output using different fuels. Results showed that there is an increase in engine efficiency only if Maximum Brake Torque (MBT) spark advance is used for each fuel. Moreover, an economic analysis has been carried out to determine the over cost of hydrogen in such blends, showing percent increments by using these fuels about between 10 and 34%. (author)

Investigations of charge-changing processes for light proton-rich nuclei on carbon and solid-hydrogen targets

Energy Technology Data Exchange (ETDEWEB)

Sawahata, K. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Ozawa, A., E-mail: ozawa@tac.tsukuba.ac.jp [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Saito, Y.; Abe, Y.; Ichikawa, Y.; Inaba, N.; Ishibashi, Y. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Kitagawa, A. [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Matsunaga, S. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Moriguchi, T.; Nagae, D.; Okada, S. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Sato, S. [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Suzuki, S. [Institute of Physics, University of Tsukuba, Ibaraki 305-8571 (Japan); Suzuki, T.; Takeuchi, Y.; Yamaguchi, T. [Department of Physics, Saitama University, Saitama 338-8570 (Japan); Zenihiro, J. [RIKEN Nishina Center, Wako, Saitama 351-0198 (Japan)

2017-05-15

We investigated charge-changing processes (total charge-changing cross sections and partial charge-changing cross sections) for light proton-rich nuclei ({sup 34–36}Ar, {sup 33}Cl, {sup 25–28}Si) at around 300A MeV on carbon and solid-hydrogen targets. We estimated the nuclear proton point radii of {sup 33}Cl and {sup 25,26,27}Si from the observed total charge-changing cross sections by using Glauber-model calculations with a phenomenological correction factor. Furthermore, we estimated the proton skin thickness for {sup 33}Cl coupled with its previously observed matter radius. From investigations of the partial charge-changing cross sections, clear zigzag pattern was observed for all isotopes. The present studies suggest that the pattern may be common in the proton-rich side, and depends on the odd–even nature of the fragment charge.

Treating landfill gas hydrogen sulphide with mineral wool waste (MWW) and rod mill waste (RMW).

Science.gov (United States)

Bergersen, Ove; Haarstad, Ketil

2014-01-01

Hydrogen sulphide (H2S) gas is a major odorant at municipal landfills. The gas can be generated from different waste fractions, for example demolition waste containing gypsum based plaster board. The removal of H2S from landfill gas was investigated by filtering it through mineral wool waste products. The flow of gas varied from 0.3 l/min to 3.0 l/min. The gas was typical for landfill gas with a mean H2S concentration of ca. 4500 ppm. The results show that the sulphide gas can effectively be removed by mineral wool waste products. The ratios of the estimated potential for sulphide precipitation were 19:1 for rod mill waste (RMW) and mineral wool waste (MWW). A filter consisting of a mixture of MWW and RMW, with a vertical perforated gas tube through the center of filter material and with a downward gas flow, removed 98% of the sulfide gas over a period of 80 days. A downward gas flow was more efficient in contacting the filter materials. Mineral wool waste products are effective in removing hydrogen sulphide from landfill gas given an adequate contact time and water content in the filter material. Based on the estimated sulphide removal potential of mineral wool and rod mill waste of 14 g/kg and 261 g/kg, and assuming an average sulphide gas concentration of 4500 ppm, the removal capacity in the filter materials has been estimated to last between 11 and 308 days. At the studied location the experimental gas flow was 100 times less than the actual gas flow. We believe that the system described here can be upscaled in order to treat this gas flow. Copyright © 2013 Elsevier Ltd. All rights reserved.

Hydrogen gas sensing feature of polyaniline/titania (rutile) nanocomposite at environmental conditions

Science.gov (United States)

Milani Moghaddam, Hossain; Nasirian, Shahruz

2014-10-01

The resistance-based sensors of polyaniline/titania (rutile) nanocomposite (TPNC) were prepared by spin coating technique onto an epoxy glass substrate with Cu-interdigited electrodes to study their hydrogen (H2) gas sensing features. Our findings are that the change of the surface morphology, porosity and wt% of titania in TPNCs have a significant effect on H2 gas sensing of sensors. All of the sensors had a reproducibility response toward 0.8 vol% H2 gas at room temperature, air pressure and 50% relative humidity. A sensor with 40 wt% of titania nanoparticles had better response/recovery time and the response than other sensors. Moreover, H2 gas sensing mechanism of TPNC sensors based contact areas and the correlation of energy levels between PANI chains and the titania grains were studied.

Plasma-neutral gas interaction in a tokamak divertor: effects of hydrogen molecules and plasma recombination

International Nuclear Information System (INIS)

Krasheninnikov, S.I.; Pigarov, A.Yu.; Soboleva, T.K.; Sigmar, D.J.

1997-01-01

We investigate the influence of hydrogen molecules on plasma recombination using a collisional-radiative model for multispecies hydrogen plasmas and tokamak detached divertor parameters. The rate constant found for molecular activated recombination of a plasma can be as high as 2 x 10 -10 cm 3 /s, confirming our pervious estimates. We investigate the effects of hydrogen molecules and plasma recombination on self-consistent plasma-neutral gas interactions in the recycling region of a tokamak divertor. We treat the plasma flow in a fluid approximation retaining the effects of plasma recombination and employing a Knudsen neutral transport model for a 'gas box' divertor geometry. For the model of plasma-neutral interactions we employ we find: (a) molecular activated recombination is a dominant channel of divertor plasma recombination; and (b) plasma recombination is a key element leading to a decrease in the plasma flux onto the target and substantial plasma pressure drop which are the main features of detached divertor regimes. (orig.)

The impact of hydrogen-bearing gas to change indexes of car engine in operating conditions

Directory of Open Access Journals (Sweden)

Korpach A.

2016-08-01

Full Text Available Due to lower oil and petroleum products there is a constant problem of the growing use of alternative fuels. One of the most promising is hydrogen, but its use as a self-fuel is rather difficult, but using as the form of supplements has prospects for widespread use in road transport. In order to establish the effectiveness of its use as a hydrogen-containing gas as a product of the electrolysis of the alkaline solution, a series of tests conducted. Tests were carried out on the car ZAZ–1102 "Tavria", which is equipped with an engine MeMZ–245 with carburetor feed system and electrolyser SuperKit 10, which is powered by the vehicle electrical system. At the same time also used electrolytic League–02. The effect on fuel economy additives hydrogen-containing gas to the air charge is determined when the engine is idling. When using additives 1,34 % interest, from the weight of the fuel, fuel efficiency has increased by 1,9 %.

Life Cycle Assessment of Hydrogen Production via Natural Gas Steam Reforming; TOPICAL

International Nuclear Information System (INIS)

Spath, P. L.; Mann, M. K.

2000-01-01

A life cycle assessment of hydrogen production via natural gas steam reforming was performed to examine the net emissions of greenhouse gases as well as other major environmental consequences. LCA is a systematic analytical method that helps identify and evaluate the environmental impacts of a specific process or competing processes

Gas-chromatographic separation of hydrogen isotopes mixtures on capillary molecular sieve 5 A column at 173 K

International Nuclear Information System (INIS)

Bidica, N.; Preda, A.; Stanciu, V.

2002-01-01

Analysis of a gas mixture of hydrogen species, is not too easy because the differences in their physical-chemical properties are very small; the most different are their masses, and consequently most common analytical method appear to be the mass-spectrometry. However, the impossibility to distinguish between two ions (atomic or molecular) with the same mass renders this method as unapplicable. Another problem is the decay of tritium with production of 3 He. These disadvantages of mass-spectrometry have made that other analytical methods, like gas chromatography, to be considered and developed. Thus, there are many papers about various chromatographic columns especially prepared for hydrogen species separation but the preparation and treatment of these columns are very difficult to reproduce. Besides these, there are two other main disadvantages: column operating temperature is very low and long retention times for hydrogen species (more than half an hour) are required. However, the gas-chromatography method still remains an appropriate one. The method described in this paper was based on using a capillary molecular sieve 5A column which has been operated for this kind of separation. The retention times were relatively short, about 8-9 minutes. The carrier gas was Ne and the detector - TCD. In the paper chromatograms for various carrier flow rates and various hydrogen isotope mixtures are presented. The results demonstrated a quite good efficiency for H 2 , HD, D 2 and a not very good one for orthoH 2 -paraH 2 . (authors)

Investigation of low-latitude hydrogen emission in terms of a two-component interstellar gas model

International Nuclear Information System (INIS)

Baker, P.L.; Burton, W.B.

1975-01-01

The high-resolution 21-cm hydrogen line observations at low galactic latitude of Burton and Verschuur have been analyzed to determine the large-scale distribution of galactic hydrogen. The distribution parameters are found by model fitting. Optical depth affects have been computed using a two-component gas model. Analysis shows that a multiphase description of the medium is essential to the interpretation of low-latitude emission observations. Where possible, the number of free parameters in the gas model has been reduced. Calculations were performed for a one-component, uniform spin temperature, gas model in order to show the systematic departures between this model and the data caused by the incorrect treatment of the optical depth effect. In the two-component gas, radiative transfer is treated by a Monte Carlo calculation since the opacity of the gas arises in a randomly distributed, cold, optically thick, low velocity-dispersion, cloud medium. The emission arises in both the cloud medium and a smoothly distributed, optically thin, high velocity-dispersion, intercloud medium. The synthetic profiles computed from the two-component model reproduce both the large-scale trends of the observed emission profiles and the magnitude of the small-scale emission irregularities. The analysis permits the determination of values for []he thickness of the galactic disk between half density points, the total observed neutral hydrogen mass of the Galaxy, and the central number density of the intercloud atoms. In addition, the analysis is sensitive to the size of clouds contributing to the observations. Computations also show that synthetic emission profiles based on the two-component model display both the zero-velocity and high-velocity ridges, indicative of optical thinness on a large scale, in spite of the presence of optically thick gas

Hydrocarbon-Rich Groundwater above Shale-Gas Formations: A Karoo Basin Case Study.

Science.gov (United States)

Eymold, William K; Swana, Kelley; Moore, Myles T; Whyte, Colin J; Harkness, Jennifer S; Talma, Siep; Murray, Ricky; Moortgat, Joachim B; Miller, Jodie; Vengosh, Avner; Darrah, Thomas H

2018-03-01

Horizontal drilling and hydraulic fracturing have enhanced unconventional hydrocarbon recovery but raised environmental concerns related to water quality. Because most basins targeted for shale-gas development in the USA have histories of both active and legacy petroleum extraction, confusion about the hydrogeological context of naturally occurring methane in shallow aquifers overlying shales remains. The Karoo Basin, located in South Africa, provides a near-pristine setting to evaluate these processes, without a history of conventional or unconventional energy extraction. We conducted a comprehensive pre-industrial evaluation of water quality and gas geochemistry in 22 groundwater samples across the Karoo Basin, including dissolved ions, water isotopes, hydrocarbon molecular and isotopic composition, and noble gases. Methane-rich samples were associated with high-salinity, NaCl-type groundwater and elevated levels of ethane, 4 He, and other noble gases produced by radioactive decay. This endmember displayed less negative δ 13 C-CH 4 and evidence of mixing between thermogenic natural gases and hydrogenotrophic methane. Atmospheric noble gases in the methane-rich samples record a history of fractionation during gas-phase migration from source rocks to shallow aquifers. Conversely, methane-poor samples have a paucity of ethane and 4 He, near saturation levels of atmospheric noble gases, and more negative δ 13 C-CH 4 ; methane in these samples is biogenic and produced by a mixture of hydrogenotrophic and acetoclastic sources. These geochemical observations are consistent with other basins targeted for unconventional energy extraction in the USA and contribute to a growing data base of naturally occurring methane in shallow aquifers globally, which provide a framework for evaluating environmental concerns related to unconventional energy development (e.g., stray gas). © 2018, National Ground Water Association.

Atomic and molecular hydrogen gas temperatures in a low-pressure helicon plasma

Science.gov (United States)

Samuell, Cameron M.; Corr, Cormac S.

2015-08-01

Neutral gas temperatures in hydrogen plasmas are important for experimental and modelling efforts in fusion technology, plasma processing, and surface modification applications. To provide values relevant to these application areas, neutral gas temperatures were measured in a low pressure (radiofrequency helicon discharge using spectroscopic techniques. The atomic and molecular species were not found to be in thermal equilibrium with the atomic temperature being mostly larger then the molecular temperature. In low power operation (measurements near a graphite target demonstrated localised cooling near the sample surface. The temporal evolution of the molecular gas temperature during a high power 1.1 ms plasma pulse was also investigated and found to vary considerably as a function of pressure.

H2-rich and Hydrocarbon Gas Recovered in a Deep Precambrian Well in Northeastern Kansas

International Nuclear Information System (INIS)

Newell, K. David; Doveton, John H.; Merriam, Daniel F.; Lollar, Barbara Sherwood; Waggoner, William M.; Magnuson, L. Michael

2007-01-01

In late 2005 and early 2006, the WTW Operating, LLC (W.T.W. Oil Co., Inc.) no. 1 Wilson well (T.D. = 5772 ft; 1759.3 m) was drilled for 1826 ft (556.6 m) into Precambrian basement underlying the Forest City Basin in northeastern Kansas. Approximately 4500 of the 380,000 wells drilled in Kansas penetrate Precambrian basement. Except for two previous wells drilled into the arkoses and basalts of the 1.1-Ga Midcontinent Rift and another well drilled in 1929 in basement on the Nemaha Uplift east of the Midcontinent Rift, this well represents the deepest penetration into basement rocks in the state to date. Granite is the typical lithology observed in wells that penetrate the Precambrian in the northern Midcontinent. Although no cores were taken to definitively identify lithologies, well cuttings and petrophysical logs indicate that this well encountered basement metamorphic rocks consisting of schist, gneiss, and amphibolitic gneiss, all cut by aplite dikes.The well was cased and perforated in the Precambrian, and then acidized. After several days of swabbing operations, the well produced shows of low-Btu gas, dominated by the non-flammable component gases of nitrogen (20%), carbon dioxide (43%), and helium (1%). Combustible components include methane (26%), hydrogen (10%), and higher molecular-weight hydrocarbons (1%). Although Coveney and others [Am. Assoc. Petroleum Geologists Bull., v. 71, no, 1, p. 39-48, 1987] identified H 2 -rich gas in two wells located close to the Midcontinent Rift in eastern Kansas, this study indicates that high levels of H 2 may be a more widespread phenomenon than previously thought. Unlike previous results, the gases in this study have a significant component of hydrocarbon gas, as well as H 2 , N 2 , and CO 2 . Although redox reactions between iron-bearing minerals and groundwater are a possible source of H 2 in the Precambrian basement rocks, the hydrocarbon gas does not exhibit the characteristics typically associated with proposed

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

Energy Technology Data Exchange (ETDEWEB)

Andre Boehman; Daniel Haworth

2008-09-30

The 'Freedom Car' Initiative announced by the Bush Administration has placed a significant emphasis on development of a hydrogen economy in the United States. While the hydrogen-fueled fuel-cell vehicle that is the focus of the 'Freedom Car' program would rely on electrochemical energy conversion, and despite the large amount of resources being devoted to its objectives, near-term implementation of hydrogen in the transportation sector is not likely to arise from fuel cell cars. Instead, fuel blending and ''hydrogen-assisted'' combustion are more realizable pathways for wide-scale hydrogen utilization within the next ten years. Thus, a large potential avenue for utilization of hydrogen in transportation applications is through blending with natural gas, since there is an existing market for natural-gas vehicles of various classes, and since hydrogen can provide a means of achieving even stricter emissions standards. Another potential avenue is through use of hydrogen to 'assist' diesel combustion to permit alternate combustion strategies that can achieve lower emissions and higher efficiency. This project focused on developing the underlying fundamental information to support technologies that will facilitate the introduction of coal-derived hydrogen into the market. Two paths were envisioned for hydrogen utilization in transportation applications. One is for hydrogen to be mixed with other fuels, specifically natural gas, to enhance performance in existing natural gas-fueled vehicles (e.g., transit buses) and provide a practical and marketable avenue to begin using hydrogen in the field. A second is to use hydrogen to enable alternative combustion modes in existing diesel engines, such as homogeneous charge compression ignition, to permit enhanced efficiency and reduced emissions. Thus, this project on hydrogen-assisted combustion encompassed two major objectives: (1) Optimization of hydrogen-natural gas mixture