Hydrogen-based power generation from bioethanol steam reforming

Science.gov (United States)

Tasnadi-Asztalos, Zs.; Cormos, C. C.; Agachi, P. S.

2015-12-01

This paper is evaluating two power generation concepts based on hydrogen produced from bioethanol steam reforming at industrial scale without and with carbon capture. The power generation from bioethanol conversion is based on two important steps: hydrogen production from bioethanol catalytic steam reforming and electricity generation using a hydrogen-fuelled gas turbine. As carbon capture method to be assessed in hydrogen-based power generation from bioethanol steam reforming, the gas-liquid absorption using methyl-di-ethanol-amine (MDEA) was used. Bioethanol is a renewable energy carrier mainly produced from biomass fermentation. Steam reforming of bioethanol (SRE) provides a promising method for hydrogen and power production from renewable resources. SRE is performed at high temperatures (e.g. 800-900°C) to reduce the reforming by-products (e.g. ethane, ethene). The power generation from hydrogen was done with M701G2 gas turbine (334 MW net power output). Hydrogen was obtained through catalytic steam reforming of bioethanol without and with carbon capture. For the evaluated plant concepts the following key performance indicators were assessed: fuel consumption, gross and net power outputs, net electrical efficiency, ancillary consumptions, carbon capture rate, specific CO2 emission etc. As the results show, the power generation based on bioethanol conversion has high energy efficiency and low carbon footprint.

Micro hydrogen for portable power : generating opportunities for hydrogen and fuel cells

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-07-01

A new fuel cell technology for portable applications was reviewed. Success for the fuel cell industry will be achieved primarily by supplanting lithium-ion batteries, and fuel cells for portable applications have clear advantages to batteries in addition to their known environmental benefits. Micro hydrogen {sup TM} is the integrated combination of hydrogen fuel cell, hydrogen storage and delivery, fluidic interconnects and power conditioning electronics required for creating high energy density portable power sources. The small size, low heat production, environmental sustainability and refueling flexibility of the systems provides enormous economic opportunities for the use of micro hydrogen in cell phone technology, personal digital assistants and other electronic gadgets. Details of a trial to test and evaluate micro hydrogen fuel cell powered bike lights were presented. Further programs are planned for external demonstrations of high-beam search and rescue lighting, flashlights for security personnel and portable hydrogen power sources that will be used by multiple organizations throughout British Columbia. It was concluded that fuel cell technology must match the lithium-ion battery's performance by providing fast recharge, high energy density, and adaptability. Issues concerning refueling and portable and disposable cartridges for micro hydrogen systems were also discussed. 8 figs.

Hydrogen fuel cell power system

International Nuclear Information System (INIS)

Lam, A.W.

2004-01-01

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

Hydrogenated Benzene in Circumstellar Environments: Insights into the Photostability of Super-hydrogenated PAHs

Science.gov (United States)

Quitián-Lara, Heidy M.; Fantuzzi, Felipe; Nascimento, Marco A. C.; Wolff, Wania; Boechat-Roberty, Heloisa M.

2018-02-01

Polycyclic aromatic hydrocarbons (PAHs), comprised of fused benzene (C6H6) rings, emit infrared radiation (3–12 μm) due to the vibrational transitions of the C–H bonds of the aromatic rings. The 3.3 μm aromatic band is generally accompanied by the band at 3.4 μm assigned to the vibration of aliphatic C–H bonds of compounds such as PAHs with an excess of peripheral H atoms (H n –PAHs). Herein we study the stability of fully hydrogenated benzene (or cyclohexane, C6H12) under the impact of stellar radiation in the photodissociation region (PDR) of NGC 7027. Using synchrotron radiation and time-of-flight mass spectrometry, we investigated the ionization and dissociation processes at energy ranges of UV (10–200 eV) and soft X-rays (280–310 eV). Density Functional Theory (DFT) calculations were used to determine the most stable structures and the relevant low-lying isomers of singly charged C6H12 ions. Partial Ion Yield (PIY) analysis gives evidence of the higher tendency toward dissociation of cyclohexane in comparison to benzene. However, because of the high photoabsorption cross-section of benzene at the C1s resonance edge, its photodissociation and photoionization cross-sections are enhanced, leading to a higher efficiency of dissociation of benzene in the PDR of NGC 7027. We suggest that a similar effect is experienced by PAHs in X-ray photon-rich environments, which ultimately acts as an auxiliary protection mechanism of super-hydrogenated polycyclic hydrocarbons. Finally, we propose that the single photoionization of cyclohexane could enhance the abundance of branched molecules in interstellar and circumstellar media.

Wind energy-hydrogen storage hybrid power generation

Energy Technology Data Exchange (ETDEWEB)

Wenjei Yang; Orhan Aydin [University of Michigan, Ann Arbor, MI (United States). Dept. of Mechanical Engineering and Applied Mechanics

2001-07-01

In this theoretical investigation, a hybrid power generation system utilizing wind energy and hydrogen storage is presented. Firstly, the available wind energy is determined, which is followed by evaluating the efficiency of the wind energy conversion system. A revised model of windmill is proposed from which wind power density and electric power output are determined. When the load demand is less than the output of the generation, the excess electric power is relayed to the electrolytic cell where it is used to electrolyse the de-ionized water. Hydrogen thus produced can be stored as hydrogen compressed gas or liquid. Once the hydrogen is stored in an appropriate high-pressure vessel, it can be used in a combustion engine, fuel cell, or burned in a water-cooled burner to produce a very high-quality steam for space heating, or to drive a turbine to generate electric power. It can also be combined with organic materials to produce synthetic fuels. The conclusion is that the system produces no harmful waste and depletes no resources. Note that this system also works well with a solar collector instead of a windmill. (author)

SUPER-CAPACITOR APPLICATION IN ELECTRICAL POWER CABLE TESTING FACILITIES IN THERMAL ENDURANCE AND MECHANICAL BRACING TESTS

Directory of Open Access Journals (Sweden)

I. V. Oleksyuk

2015-01-01

Full Text Available The current-carrying cores of the electrical power cables should be resistant to effects of short-circuit currents whose values depend on the material of the core, its cross-sectional area, cable insulation properties, environment temperature, and the duration of the short-circuit current flow (1 and 3–4 sec. when tested for thermal endurance and mechanical bracing. The facilities for testing the 10 kV aluminum core cables with short-circuit current shall provide mechanical-bracing current 56,82 kA and thermal endurance current 11,16 kA. Although capacitors provide such values of the testing currents to the best advantage, utilizing conventional capacitor-units will involve large expenditures for erecting and  running a separate building. It is expedient to apply super-capacitors qua the electric power supply for testing facilities, as they are capacitors with double-electrical layer and involve the current values of tens of kilo-amperes.The insulation voltage during short-circuit current testing being not-standardized, it is not banned to apply voltages less than 10 kV when performing short-circuit thermal endurance and mechanical bracing tests for electrical power cables of 10 kV. The super-capacitor voltage variation-in-time graph consists of two regions: capacitive and resistive. The capacitive part corresponds to the voltage change consequent on the energy change in the super-capacitors. The resistive part shows the voltage variation due to the active resistance presence in the super-capacitor.The author offers the algorithm determining the number of super capacitors requisite for testing 10 kV-electrical power cables with short-circuit currents for thermal endurance and mechanical bracing. The paper shows that installation of super-capacitors in the facilities testing the cables with short-circuit currents reduces the area needed for the super-capacitors in comparison with conventional capacitors more than by one order of magnitude.

Super thermal power plants and environment: a critical appraisal

International Nuclear Information System (INIS)

Sharma, A.K.

1995-01-01

This paper discusses the possible impact on the environment by the particulate matters, oxides of sulphur and nitrogen, trace metals and solid/liquid wastes, which are emitted during the combustion of coal in the super thermal power plants of National Thermal Power Corporation (NTPC). The coal consumed by these plants have sufficient sulphur content and ash. Of all the mineral in coal, pyrite is one of the most deleterious in combustion and a major source of oxide of sulphur pollution of the atmosphere. The impact of these on the terrestrial and aquatic environment in and around power plants and on region have been discussed. To arresting such contaminants, some remedial measures are suggested. (author). 14 refs., 1 fig., 3 tabs

Hydrogen-powered lawn mower: 14 years of operation

International Nuclear Information System (INIS)

Yvon, K.; Lorenzoni, J.-L.

2006-01-01

Our hydrogen-powered lawn mower [Yvon K, Lorenzoni J-L. Hydrogen powered lawn mower. Int J Hydrogen Energy 1993; 18, 345-48] has been operated without major interruption during the past 14 years. The commercial model was originally running on gasoline and was adapted to hydrogen by making small adjustments to the carburettor and by installing a hydrogen reservoir containing solid-state metal hydrides. During the evaluation period the only maintenance work was changing the lubricating oil of the engine once a year, and reactivating the metal hydride powder by external heating after an accidental inlet of air into the reservoir. There occurred no technical failure, and there was no safety incident, neither during operation nor during recharging of hydrogen. This demonstrates that a hydrogen-operated device of this type is mature for use by greater public. Cost and marketing issues are discussed. (author)

Origin and Quenching of Novel ultraviolet and blue emission in NdGaO3: Concept of Super-Hydrogenic Dopants.

Science.gov (United States)

Ghosh, Siddhartha; Saha, Surajit; Liu, Zhiqi; Motapothula, M; Patra, Abhijeet; Yakovlev, Nikolai; Cai, Yao; Prakash, Saurav; Huang, Xiao Hu; Tay, Chuan Beng; Cong, Chun Xiao; Bhatt, Thirumaleshwara; Dolmanan, Surani B; Chen, Jianqiang; Lü, Weiming; Huang, Zhen; Tripathy, Sudhiranjan; Chua, Soo Jin; Yu, Ting; Asta, Mark; Ariando, A; Venkatesan, T

2016-11-03

In this study we report the existence of novel ultraviolet (UV) and blue emission in rare-earth based perovskite NdGaO 3 (NGO) and the systematic quench of the NGO photoluminescence (PL) by Ce doping. Study of room temperature PL was performed in both single-crystal and polycrystalline NGO (substrates and pellets) respectively. Several NGO pellets were prepared with varying Ce concentration and their room temperature PL was studied using 325 nm laser. It was found that the PL intensity shows a systematic quench with increasing Ce concentration. XPS measurements indicated that nearly 50% of Ce atoms are in the 4+ state. The PL quench was attributed to the novel concept of super hydrogenic dopant (SHD)", where each Ce 4+ ion contributes an electron which forms a super hydrogenic atom with an enhanced Bohr radius, due to the large dielectric constant of the host. Based on the critical Ce concentration for complete quenching this SHD radius was estimated to be within a range of 0.85 nm and 1.15 nm whereas the predicted theoretical value of SHD radius for NdGaO3 is ~1.01 nm.

Market Penetration Simulation of Hydrogen Powered Vehicles in Korea

International Nuclear Information System (INIS)

Eunju Jun; Yong Hoon, Jeong; Soon Heung, Chang

2006-01-01

As oil price being boosted, hydrogen has been considered to be a strong candidate for the future energy carrier along with electricity. Although hydrogen can be produced by many energy sources, carbon-free sources such as nuclear and renewable energy may be ideal ones due to their environmental friendliness. For the analysis of hydrogen economy, the cost and market penetration of various end-use technologies are the most important factors in production and consumer side, respectively. Particularly, hydrogen powered vehicle is getting more interests as fuel cell technologies are developed. In this paper, the hydrogen powered vehicle penetration into the transportation market is simulated. A system dynamic code, Vensim, was utilized to simulate the dynamics in the transportation, assuming various types of vehicle such as gasoline, hybrid electricity and hydrogen powered. Market shares of each vehicle are predicted by using currently available data. The result showed that hydrogen era will not be bright as we think. To reach the era of hydrogen fuel cell cost should be reduced dramatically. And if the hydrogen cost which includes both operating and capital cost reaches to a $0.16 per kilometer, hydrogen portion can be a 50 percent in the transportation sector. However, if strong policy or subsidy can be given, the result will be changed. [1] (authors)

Supercluster simulations: impact of baryons on the matter power spectrum and weak lensing forecasts for Super-CLASS

Science.gov (United States)

Peters, Aaron; Brown, Michael L.; Kay, Scott T.; Barnes, David J.

2018-03-01

We use a combination of full hydrodynamic and dark matter only simulations to investigate the effect that supercluster environments and baryonic physics have on the matter power spectrum, by re-simulating a sample of supercluster sub-volumes. On large scales we find that the matter power spectrum measured from our supercluster sample has at least twice as much power as that measured from our random sample. Our investigation of the effect of baryonic physics on the matter power spectrum is found to be in agreement with previous studies and is weaker than the selection effect over the majority of scales. In addition, we investigate the effect of targeting a cosmologically non-representative, supercluster region of the sky on the weak lensing shear power spectrum. We do this by generating shear and convergence maps using a line-of-sight integration technique, which intercepts our random and supercluster sub-volumes. We find the convergence power spectrum measured from our supercluster sample has a larger amplitude than that measured from the random sample at all scales. We frame our results within the context of the Super-CLuster Assisted Shear Survey (Super-CLASS), which aims to measure the cosmic shear signal in the radio band by targeting a region of the sky that contains five Abell clusters. Assuming the Super-CLASS survey will have a source density of 1.5 galaxies arcmin-2, we forecast a detection significance of 2.7^{+1.5}_{-1.2}, which indicates that in the absence of systematics the Super-CLASS project could make a cosmic shear detection with radio data alone.

Power ramp performance of some 15 x 15 PWR test fuel rods tested in the STUDSVIK SUPER-RAMP and SUPER-RAMP extension projects

International Nuclear Information System (INIS)

Djurle, S.

2000-01-01

This paper presents results obtained from the STUDSVIK SUPER-RAMP (SR) and SUPER-RAMP EXTENSION (SRX) projects. As parts of these projects test fuel rods of the same PWR type were base irradiated in the Obrigheim power reactor and power ramp tested in the STUDSVIK R2 reactor. Some of the rods were ramped using an inlet coolant water temperature 50 deg. C below the normal one. Fabricated data on the test fuel rods are presented as well as data on the base irradiation, interim examination, conditioning irradiation, power ramp irradiation and results of the post irradiation examination. The data on the change of diameter at ridges due to power ramping have shown that a lower clad temperature during ramping leads to smaller deformations. Most likely this may be explained as due to a smaller creep rate in the cladding at the lower temperature, resulting in a more severe stress situation. The combination of low cladding temperature, high ramp terminal level and the presence of a stress corrosion agent may have caused the failure of one of the test rods. (author)

No hydrogen exosphere detected around the super-Earth HD 97658 b

Science.gov (United States)

Bourrier, V.; Ehrenreich, D.; King, G.; Lecavelier des Etangs, A.; Wheatley, P. J.; Vidal-Madjar, A.; Pepe, F.; Udry, S.

2017-01-01

The exoplanet HD 97658 b provides a rare opportunity to probe the atmospheric composition and evolution of moderately irradiated super-Earths. It transits a bright K star at a moderate orbital distance of 0.08 au. Its low density is compatible with a massive steam envelope that could photodissociate at high altitudes and become observable as escaping neutral hydrogen. Our analysis of three transits with HST/STIS at Lyman-α reveals no such signature, suggesting that the thermosphere of HD 97658 b is not hydrodynamically expanding and is subjected to a low escape of neutral hydrogen (soft X-ray source with signs of chromospheric variability in the Lyman-α line core. We determine an average reference for the intrinsic Lyman-α line and X-EUV (XUV) spectrum of the star, and show that HD 97658 b is in mild conditions of irradiation compared to other known evaporating exoplanets with an XUV irradiation about three times lower than the evaporating warm Neptune GJ436 b. This could be the reason why the thermosphere of HD 97658 b is not expanding: the low XUV irradiation prevents an efficient photodissociation of any putative steam envelope. Alternatively, it could be linked to a low hydrogen content or inefficient conversion of the stellar energy input. The HD 97658 system provides clues for understanding the stability of low-mass planet atmospheres in terms of composition, planetary density, and irradiation. Our study of HD 97658 b can be seen as a control experiment of our methodology, confirming that it does not bias detections of atmospheric escape and underlining its strength and reliability. Our results show that stellar activity can be efficiently discriminated from absorption signatures by a transiting exospheric cloud. They also highlight the potential of observing the upper atmosphere of small transiting planets to probe their physical and chemical properties.

THEORETICAL TRANSIT SPECTRA FOR GJ 1214b AND OTHER 'SUPER-EARTHS'

Energy Technology Data Exchange (ETDEWEB)

Howe, Alex R.; Burrows, Adam S., E-mail: arhowe@astro.princeton.edu, E-mail: burrows@astro.princeton.edu [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544 (United States)

2012-09-10

We present new calculations of transit spectra of super-Earths that allow for atmospheres with arbitrary proportions of common molecular species and haze. We test this method with generic spectra, reproducing the expected systematics and absorption features, then apply it to the nearby super-Earth GJ 1214b, which has produced conflicting observational data, leaving the questions of a hydrogen-rich versus hydrogen-poor atmosphere and the water content of the atmosphere ambiguous. We present representative transit spectra for a range of classes of atmosphere models for GJ 1214b. Our analysis supports a hydrogen-rich atmosphere with a cloud or haze layer, although a hydrogen-poor model with {approx}<10% water is not ruled out. Several classes of models are ruled out, however, including hydrogen-rich atmospheres with no haze, hydrogen-rich atmospheres with a haze of {approx}0.01 {mu}m tholin particles, and hydrogen-poor atmospheres with major sources of absorption other than water. We propose an observational test to distinguish hydrogen-rich from hydrogen-poor atmospheres. Finally, we provide a library of theoretical transit spectra for super-Earths with a broad range of parameters to facilitate future comparison with anticipated data.

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

Galaxy power-spectrum responses and redshift-space super-sample effect

Science.gov (United States)

Li, Yin; Schmittfull, Marcel; Seljak, Uroš

2018-02-01

As a major source of cosmological information, galaxy clustering is susceptible to long-wavelength density and tidal fluctuations. These long modes modulate the growth and expansion rate of local structures, shifting them in both amplitude and scale. These effects are often named the growth and dilation effects, respectively. In particular the dilation shifts the baryon acoustic oscillation (BAO) peak and breaks the assumption of the Alcock-Paczynski (AP) test. This cannot be removed with reconstruction techniques because the effect originates from long modes outside the survey. In redshift space, the long modes generate a large-scale radial peculiar velocity that affects the redshift-space distortion (RSD) signal. We compute the redshift-space response functions of the galaxy power spectrum to long density and tidal modes at leading order in perturbation theory, including both the growth and dilation terms. We validate these response functions against measurements from simulated galaxy mock catalogs. As one application, long density and tidal modes beyond the scale of a survey correlate various observables leading to an excess error known as the super-sample covariance, and thus weaken their constraining power. We quantify the super-sample effect on BAO, AP, and RSD measurements, and study its impact on current and future surveys.

Functionalization of super-aligned carbon nanotube film using hydrogen peroxide solution and its application in copper electrodeposition.

Science.gov (United States)

Xiong, Lunqiao; Shuai, Jing; Hou, Zecheng; Zhu, Lin; Li, Wenzhen

2017-07-15

In order to make super-aligned carbon nanotubes (SACNT) homogeneously spread in electrolytes, a swift and effective method was devised for surface functionalization of SACNT film by ohmic heating using hydrogen peroxide solution. Controllable generation of defects and notable graft of oxygen functional groups on the sidewall of SACNTs were induced as proven by X-ray photoelectron spectroscopy and Raman spectroscopy. Differently from the harsh wet chemical oxidation, the super-aligned morphology and structural integrity of carbon nanotubes in the SACNT film were found to be well preserved by electron microscopy analysis. The functionalized treatment can remove extraneous material contaminating SACNT film and improve its conductivity. The grafting of polar ionizable groups has been proved to effectively eliminate the agglomeration of SACNTs. When the oxidized SACNT film was used as host material for electrodeposition of copper, the composite film of well-bonded SACNTs and Cu was successfully prepared. Copyright © 2017 Elsevier Inc. All rights reserved.

Scenarios of hydrogen production from wind power

Energy Technology Data Exchange (ETDEWEB)

Klaric, Mario

2010-09-15

Since almost total amount of hydrogen is currently being produced from natural gas, other ways of cleaner and 'more renewable' production should be made feasible in order to make benchmarks for total 'hydrogen economy'. Hydrogen production from wind power combined with electrolysis imposes as one possible framework for new economy development. In this paper various wind-to-hydrogen scenarios were calculated. Cash flows of asset based project financing were used as decision making tool. Most important parameters were identified and strategies for further research and development and resource allocation are suggested.

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

OpenAIRE

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

2015-01-01

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

Mitigation of Hydrogen Hazards in Severe Accidents in Nuclear Power Plants

International Nuclear Information System (INIS)

2011-07-01

Consideration of severe accidents in nuclear power plants is an essential component of the defence in depth approach in nuclear safety. Severe accidents have very low probabilities of occurring, but may have significant consequences resulting from the degradation of nuclear fuel. The generation of hydrogen and the risk of hydrogen combustion, as well as other phenomena leading to overpressurization of the reactor containment in case of severe accidents, represent complex safety issues in relation to accident management. The combustion of hydrogen, produced primarily as a result of heated zirconium metal reacting with steam, can create short term overpressure or detonation forces that may exceed the strength of the containment structure. An understanding of these phenomena is crucial for planning and implementing effective accident management measures. Analysis of all the issues relating to hydrogen risk is an important step for any measure that is aimed at the prevention or mitigation of hydrogen combustion in reactor containments. The main objective of this publication is to contribute to the implementation of IAEA Safety Standards, in particular, two IAEA Safety Requirements: Safety of Nuclear Power Plants: Design and Safety of Nuclear Power Plants: Operation. These Requirements publications discuss computational analysis of severe accidents and accident management programmes in nuclear power plants. Specifically with regard to the risk posed by hydrogen in nuclear power reactors, computational analysis of severe accidents considers hydrogen sources, hydrogen distribution, hydrogen combustion and control and mitigation measures for hydrogen, while accident management programmes are aimed at mitigating hydrogen hazards in reactor containments.

The super-Turing computational power of plastic recurrent neural networks.

Science.gov (United States)

Cabessa, Jérémie; Siegelmann, Hava T

2014-12-01

We study the computational capabilities of a biologically inspired neural model where the synaptic weights, the connectivity pattern, and the number of neurons can evolve over time rather than stay static. Our study focuses on the mere concept of plasticity of the model so that the nature of the updates is assumed to be not constrained. In this context, we show that the so-called plastic recurrent neural networks (RNNs) are capable of the precise super-Turing computational power--as the static analog neural networks--irrespective of whether their synaptic weights are modeled by rational or real numbers, and moreover, irrespective of whether their patterns of plasticity are restricted to bi-valued updates or expressed by any other more general form of updating. Consequently, the incorporation of only bi-valued plastic capabilities in a basic model of RNNs suffices to break the Turing barrier and achieve the super-Turing level of computation. The consideration of more general mechanisms of architectural plasticity or of real synaptic weights does not further increase the capabilities of the networks. These results support the claim that the general mechanism of plasticity is crucially involved in the computational and dynamical capabilities of biological neural networks. They further show that the super-Turing level of computation reflects in a suitable way the capabilities of brain-like models of computation.

Role of hydrogen in future North European power system in 2060

DEFF Research Database (Denmark)

Meibom, Peter; Karlsson, Kenneth Bernard

2010-01-01

the heat production in heat pumps and electric heat boilers, and by varying the production of hydrogen in electrolysis plants in combination with hydrogen storage. Investment in hydrogen storage capacity corresponded to 1.2% of annual wind power production in the scenarios without a hydrogen demand from...... the future success of fuel cell technologies have been investigated as well as different electricity and heat demand assumptions. The variability of wind power production was handled by varying the hydropower production and the production on CHP plants using biomass, by power transmission, by varying...

Energy Management and Simulation of Photovoltaic/Hydrogen /Battery Hybrid Power System

Directory of Open Access Journals (Sweden)

Tariq Kamal

2016-06-01

Full Text Available This manuscript focuses on a hybrid power system combining a solar photovoltaic array and energy storage system based on hydrogen technology (fuel cell, hydrogen tank and electrolyzer and battery. The complete architecture is connected to the national grid through power converters to increase the continuity of power. The proposed a hybrid power system is designed to work under classical-based energy management algorithm. According to the proposed algorithm, the PV has the priority in meeting the load demands. The hydrogen technology is utilized to ensure long-term energy balance. The battery is used as a backup and/or high power device to take care of the load following problems of hydrogen technology during transient. The dynamic performance of a hybrid power system is tested under different solar radiation, temperature and load conditions for the simulation of 24 Hrs. The effectiveness of the proposed system in terms of power sharing, grid stability, power quality and voltage regulation is verified by Matlab simulation results.

Dependence of RF power on the content and configuration of hydrogen in amorphous hydrogenated silicon by reactive sputtering

Energy Technology Data Exchange (ETDEWEB)

Imura, T; Ushita, K; Mogi, K; Hiraki, A [Osaka Univ., Suita (Japan). Faculty of Engineering

1981-06-01

Infrared absorption spectra at stretching bands of Si-H were investigated in hydrogenated amorphous silicon fabricated by reactive sputtering in the atmosphere of Ar and H/sub 2/ (10 mole%) at various input rf powers in the range from 0.8 to 3.8 W/cm/sup 2/. Hydrogen content mainly due to the configuration of Si=H/sub 2/ in the film increased with the decreasing rf power, as the deposition rate was decreased. On the other hand, the quantity of the monohydride (Si-H) configuration depended less on the power. Attachment of hydrogen molecules onto the fresh and reactive surface of silicon deposited successively was proposed for possible process of hydrogen incusion into amorphous silicon resulting in Si=H/sub 2/ configuration. The photoconductivity increased as the input power became higher, when the deposition rate also increased linearly with the power.

Cogeneration (hydrogen and electrical power) using the Texaco Gasification Power Systems (TGPS) technology

International Nuclear Information System (INIS)

Gardner, J.

1994-01-01

The information herein presents preliminary technical and cost data for an actual case study using Texaco Gasification Power Systems (TGPS) technology, incorporated as part of an overall refinery upgrade project. This study is based on gasification of asphalt and vacuum residue (see Table 1, feedstock properties) to produce hydrogen plus carbon monoxide (synthesis gas) for the ultimate production of high purity hydrogen and power at a major refinery in Eastern Europe. A hydrogen production of 101,000 Nm 3 /hr (9.1 tons/hr) at 99.9 (wt.%) purity plus 50 MW (net) power slated to be used by the refinery was considered for this study. Figure I shows a block diagram depicting the general refinery configuration upgrade as envisioned by the owner operator; included in the configuration as shown in the shaded area is the TGPS plant. Figure II shows a block flow diagram depicting the TGPS unit and its battery limits as defined for this project. The technology best suited to meet the demand for clean and efficient electric power generation and hydrogen production is the Texaco Gasification Power Systems (TGPS) process. This technology is based upon Texaco's proprietary gasification technology which is well proven with over 40 years of gasification experience. There are currently 37 operating units in the world today which have licensed the Texaco gasification process technology, with another 12 in design/construction. Total synthesis gas (hydrogen + carbon monoxide) production capacity is over 2,8 billion standard cubic feet per day. The TGPS, which is basically the Integrated Gasification Combined Cycle (IGCC) based upon the Texaco gasification technology, was developed by combining and integrating gasification with power generation facilities. (author). 3 figs., 9 tabs., 4 refs

Hydrogen Monitoring in Nuclear Power Cycles

International Nuclear Information System (INIS)

Maurer, Heini; Staub, Lukas

2012-09-01

Maintaining constant Hydrogen levels in Nuclear power cycles is always associated with the challenge to determine the same reliably. Grab sample analysis is complicated and costly and online instruments currently known are difficult to maintain, verify and calibrate. Although amperometry has been proven to be the most suitable measuring principle for online instruments, it has never been thoroughly investigated what electrode materials would best perform in terms of measurement drift and regeneration requirements. This paper we will cover the findings of a research program, conducted at the R and D centre of Swan Analytische Instrumente AG in Hinwil Switzerland, aimed to find ideal electrode materials and sensor design to provide the nuclear industry with an enhanced method to determine dissolved hydrogen in nuclear power cycles. (authors)

Hydrogen Fuel Cell Analysis: Lessons Learned from Stationary Power Generation Final Report

Energy Technology Data Exchange (ETDEWEB)

Scott E. Grasman; John W. Sheffield; Fatih Dogan; Sunggyu Lee; Umit O. Koylu; Angie Rolufs

2010-04-30

This study considered opportunities for hydrogen in stationary applications in order to make recommendations related to RD&D strategies that incorporate lessons learned and best practices from relevant national and international stationary power efforts, as well as cost and environmental modeling of pathways. The study analyzed the different strategies utilized in power generation systems and identified the different challenges and opportunities for producing and using hydrogen as an energy carrier. Specific objectives included both a synopsis/critical analysis of lessons learned from previous stationary power programs and recommendations for a strategy for hydrogen infrastructure deployment. This strategy incorporates all hydrogen pathways and a combination of distributed power generating stations, and provides an overview of stationary power markets, benefits of hydrogen-based stationary power systems, and competitive and technological challenges. The motivation for this project was to identify the lessons learned from prior stationary power programs, including the most significant obstacles, how these obstacles have been approached, outcomes of the programs, and how this information can be used by the Hydrogen, Fuel Cells & Infrastructure Technologies Program to meet program objectives primarily related to hydrogen pathway technologies (production, storage, and delivery) and implementation of fuel cell technologies for distributed stationary power. In addition, the lessons learned address environmental and safety concerns, including codes and standards, and education of key stakeholders.

Sliding mode control of an autonomous parallel fuel cell-super capacitor power source

Energy Technology Data Exchange (ETDEWEB)

More, Jeronimo J. [Universidad Nacional de La Plata (UNLP), La Plata, Buenos Aires (Argentina). Facultad de Ingenieria. Lab. de Electronica Industrial, Control e Instrumentacion], Email: jmore@ing.unlp.edu.ar; Puleston, Paul F [Consejo de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires (Argentina); Kunusch, Cristian; Colomer, Jordi Riera I [Universitat Politecnica de Catalunya, Barcelona (Spain). Inst. de Robotica i Informatica Industrial (IRII)

2010-07-01

Nowadays, hydrogen fuel cell (FC) based systems emerge as one promising renewable alternative to fossil fuel systems in automotive and residential applications. However, their output dynamic response is relatively slow, mostly due to water and reactant gases dynamics. To overcome this limitation, FC-super capacitors (SCs) topologies can be used. The latter is capable of managing very fast power variations, presenting in addition high power density, long life cycle and good charge/discharge efficiency. In this work, a FC-SCs-based autonomous hybrid system for residential applications is considered. The FC and SCs are connected in parallel, through two separate DC/DC converters, to a DC bus. Under steady state conditions, the FC must deliver the load power requirement, while maintaining the SCs voltage regulated to the desired value. Under sudden load variations, the FC current rate must be limited to assure a safe transition to the new point of operation. During this current rate limitation mode, the SCs must deliver or absorb the power difference. To this end, a sliding mode strategy is proposed to satisfy to control objectives. The main one is the robust regulation of the DC bus voltage, even in the presence of system uncertainties and disturbances, such as load changes and FC voltage variations. Additionally, a second control objective is attained, namely to guarantee the adequate level of charge in the SCs, once the FC reaches the new steady state operation point. In this way, the system can meet the load power demand, even under sudden changes, and it can also satisfy a power demand higher than the nominal FC power, during short periods. The proposed control strategy is evaluated exhaustively by computer simulation considering fast load variations. The results presented in this work, corresponds to the first stage of a R and D collaboration project for the design and development of a novel FC-SCs-based autonomous hybrid system. In the next phase, the proposed

Sliding mode control of an autonomous parallel fuel cell-super capacitor power source

Energy Technology Data Exchange (ETDEWEB)

More, Jeronimo J. [Universidad Nacional de La Plata (UNLP), La Plata, Buenos Aires (Argentina). Facultad de Ingenieria. Lab. de Electronica Industrial, Control e Instrumentacion], Email: jmore@ing.unlp.edu.ar; Puleston, Paul F. [Consejo de Investigaciones Cientificas y Tecnicas (CONICET), Buenos Aires (Argentina); Kunusch, Cristian; Colomer, Jordi Riera I. [Universitat Politecnica de Catalunya, Barcelona (Spain). Inst. de Robotica i Informatica Industrial (IRII)

2010-07-01

Nowadays, hydrogen fuel cell (FC) based systems emerge as one promising renewable alternative to fossil fuel systems in automotive and residential applications. However, their output dynamic response is relatively slow, mostly due to water and reactant gases dynamics. To overcome this limitation, FC-super capacitors (SCs) topologies can be used. The latter is capable of managing very fast power variations, presenting in addition high power density, long life cycle and good charge/discharge efficiency. In this work, a FC-SCs-based autonomous hybrid system for residential applications is considered. The FC and SCs are connected in parallel, through two separate DC/DC converters, to a DC bus. Under steady state conditions, the FC must deliver the load power requirement, while maintaining the SCs voltage regulated to the desired value. Under sudden load variations, the FC current rate must be limited to assure a safe transition to the new point of operation. During this current rate limitation mode, the SCs must deliver or absorb the power difference. To this end, a sliding mode strategy is proposed to satisfy to control objectives. The main one is the robust regulation of the DC bus voltage, even in the presence of system uncertainties and disturbances, such as load changes and FC voltage variations. Additionally, a second control objective is attained, namely to guarantee the adequate level of charge in the SCs, once the FC reaches the new steady state operation point. In this way, the system can meet the load power demand, even under sudden changes, and it can also satisfy a power demand higher than the nominal FC power, during short periods. The proposed control strategy is evaluated exhaustively by computer simulation considering fast load variations. The results presented in this work, corresponds to the first stage of a R and D collaboration project for the design and development of a novel FC-SCs-based autonomous hybrid system. In the next phase, the proposed

On the Super-Turing Computational Power of Non-Uniform Families of Neuromata

Czech Academy of Sciences Publication Activity Database

Wiedermann, Jiří

2002-01-01

Roč. 12, č. 5 (2002), s. 509-516 ISSN 1210-0552. [SOFSEM 2002 Workshop on Soft Computing. Milovy, 28.11.2002-29.11.2002] R&D Projects: GA ČR GA201/00/1489 Institutional research plan: AV0Z1030915 Keywords : neuromata * Turing machines with advice * non-uniform computational complexity * super-Turing computational power Subject RIV: BA - General Mathematics

Super-quasi-conformal transformation and Schiffer variation on super-Riemann surface

International Nuclear Information System (INIS)

Takahasi, Wataru

1990-01-01

A set of equations which characterizes the super-Teichmueller deformations is proposed. It is a supersymmetric extension of the Beltrami equation. Relations between the set of equations and the Schiffer variations with the KN bases are discussed. This application of the KN bases shows the powerfulness of the KN theory in the study of super-Riemann surfaces. (author)

Report on achievements in fiscal 1999. Research and development of electric power storage using high-temperature super-conductive flywheels (research and development on manufacture of super-conductive magnetic bearings); 1999 nendo koon chodendo flywheel denryoku chozo kenkyu kaihatsu. Chodendo jiki jikuuke no seisaku no kenkyu kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-05-01

Introduction of electric power storage equipment is sought, which will be discretely installed in power distribution substations. Therefore, elementary technologies were researched on 'manufacture of super-conductive magnetic bearings' intended for practical application of an electric power storage system of 10-MWh class using high-temperature super-conductive flywheels. Research and development has been performed on different kinds of super-conductive magnetic bearings which combine high-temperature super-conductive materials with permanent magnets. In order to measure the characteristics of the super-conductive magnetic bearings, measurements were executed on rotation loss, loading power and bearing constants. In the measurement of the rotation loss, a {phi} 180 axial type super-conductive magnetic bearing using an Sm-based superconductor ({phi} 180AxSMB2) was given various kinds of tests by using a rotation loss measuring and testing machine. The results were compared with those for the {phi} 180AxSMB1 using the YBCO-based superconductor and other SMBs. In the measurements for the other items, various items were measured on dynamic rotation properties of the {phi} 180AxSMB and {phi} 180RaSMB by using a static bearing constant testing machine. In discussing the loading power characteristics, the dynamic rotation properties of the {phi} 180RaSMB were measured, and the loading power characteristics were discussed on super-conductive magnetic bearings for medium size models and super-conductive magnetic bearings for large system FS. (NEDO)

Hydrogen from nuclear power

International Nuclear Information System (INIS)

Miller, A.I.

2006-01-01

A few years ago, one frequently heard the view that LNG would cap the price of natural gas in North America at around 5 or 6 US$/GJ just as soon as sufficient terminal capacity could be installed. Recent experience with international LNG prices suggests that this is unlikely. While oil and gas prices have proven almost impossible to predict it seems likely that the price of gas will in future broadly track its energy equivalent in oil. Consequently, planning for natural gas at 10 $/GJ would seem prudent. Using steam-methane reforming, this produces hydrogen at 1500 $/t. If CO 2 has to be sequestered, adding another 500 $/t H 2 is a likely additional cost. So is water electrolysis now competitive? Electrolysis would deliver hydrogen at 2000$/t if electricity costs 3.7 US cents/kWh. This is lower than the Alberta Pool average supply price but very close to AECL's estimated cost for power from a new reactor. However, electricity prices in deregulated markets vary hugely and there would be large leverage on the hydrogen price in delivering a mix of electricity (when the Pool price is high) and hydrogen (when it is low). The key to that possibility - as well as other issues of interruptibility - is low-cost cavern storage, similar to that used for natural gas. One long-standing example for hydrogen storage exists in the UK. The nuclear-electrolysis route offers long-term price stability. It also has co-product possibilities if a use can be found for oxygen (equivalent to about 300 $/t H 2 ) and to produce heavy water (provided the scale is at least 100 MW)

The cost of electrolytic hydrogen from off-peak power

International Nuclear Information System (INIS)

Stucki, S.

1991-01-01

The cost of electrolytic hydrogen depends on the capacity factor of the plant and the cost of electricity. Both these parameters are correlated if off-peak power is to be used for hydrogen production. Based on assumptions regarding the correlation between the electricity price and the availability of electric power, optimizations were run using a simple cost model for the electrolysis plant. The current density at which the electrolysis plant would be run is taken as a variable for optimization as well as the annual time of availability of electric power. The results of the optimizations show for a number of hypothetical electrolyser types that the optimum operation time or electricity price do not depend much on the technology used. Production cost of electrolytic hydrogen can, however, be cut by 30% by using advanced electrolysis technology. (author)

Hydrogen-Poor Core-Collapse Supernovae

Science.gov (United States)

Pian, Elena; Mazzali, Paolo A.

Hydrogen-poor core-collapse supernovae (SNe) signal the explosive death of stars more massive than the progenitors of hydrogen-rich core-collapse supernovae, i.e., approximately in the range 15-50 M⊙ in main sequence. Since hydrogen-poor core-collapse supernovae include those that accompany gamma-ray bursts (GRBs), which were all rigorously identified with type Ic supernovae, their explosion energies cover almost two decades. The light curves and spectra are consequently very heterogeneous and often bear the signature of an asymmetric, i.e., aspherical, explosion. Asphericity is best traced by early-time (within days of the explosion) optical spectropolarimetry and by late-epoch (more than ˜ 100 days after explosion) low-resolution spectroscopy. While the relationship between hydrogen-poor core-collapse supernovae to hydrogen-poor super-luminous supernovae is not understood, a known case of association between an ultra-long gamma-ray burst and a very luminous hydrogen-poor supernova may help unraveling the connection. This is tantalizingly pointing to a magnetar powering source for both phenomena, although this scenario is still highly speculative. Host galaxies of hydrogen-poor supernovae are always star forming; in those of completely stripped supernovae and gamma-ray burst supernovae, the spatial distribution of the explosions follows the blue/ultraviolet light, with a correlation that is more than linear.

Analysis of combined hydrogen, heat, and power as a bridge to a hydrogen transition.

Energy Technology Data Exchange (ETDEWEB)

Mahalik, M.; Stephan, C. (Decision and Information Sciences)

2011-01-18

Combined hydrogen, heat, and power (CHHP) technology is envisioned as a means to providing heat and electricity, generated on-site, to large end users, such as hospitals, hotels, and distribution centers, while simultaneously producing hydrogen as a by-product. The hydrogen can be stored for later conversion to electricity, used on-site (e.g., in forklifts), or dispensed to hydrogen-powered vehicles. Argonne has developed a complex-adaptive-system model, H2CAS, to simulate how vehicles and infrastructure can evolve in a transition to hydrogen. This study applies the H2CAS model to examine how CHHP technology can be used to aid the transition to hydrogen. It does not attempt to predict the future or provide one forecast of system development. Rather, the purpose of the model is to understand how the system works. The model uses a 50- by 100-mile rectangular grid of 1-square-mile cells centered on the Los Angeles metropolitan area. The major expressways are incorporated into the model, and local streets are considered to be ubiquitous, except where there are natural barriers. The model has two types of agents. Driver agents are characterized by a number of parameters: home and job locations, income, various types of 'personalities' reflective of marketing distinctions (e.g., innovators, early adopters), willingness to spend extra money on 'green' vehicles, etc. At the beginning of the simulations, almost all driver agents own conventional vehicles. They drive around the metropolitan area, commuting to and from work and traveling to various other destinations. As they do so, they observe the presence or absence of facilities selling hydrogen. If they find such facilities conveniently located along their routes, they are motivated to purchase a hydrogen-powered vehicle when it becomes time to replace their present vehicle. Conversely, if they find that they would be inconvenienced by having to purchase hydrogen earlier than necessary or if they

Synfuel (hydrogen) production from fusion power

International Nuclear Information System (INIS)

Krakowski, R.A.; Cox, K.E.; Pendergrass, J.H.; Booth, L.A.

1979-01-01

A potential use of fusion energy for the production of synthetic fuel (hydrogen) is described. The hybrid-thermochemical bismuth-sulfate cycle is used as a vehicle to assess the technological and economic merits of this potential nonelectric application of fusion power

About connection between atomic and hydrogen energy power

International Nuclear Information System (INIS)

Avdeeva, M.Zh.; Vecher, A.A.; Pan'kov, V.V.

2008-01-01

Possible interaction between atomic and hydrogen energy power has been discussed. The analysis of the result held shows that the electrical energy produced by the atomic reactor during the of-load hours can be involved into the process of obtaining hydrogen by electrolysis. In order to optimize the transportation and storage of hydrogen it is proposed to convert it into ammonia. The direct uses of ammonia as a fuel into the internal combustion engine and fuel cells are examined. (authors)

Coal resources of the eastern regions of Russia for power plants of the Asian super ring

Science.gov (United States)

Sokolov, Aleksander; Takaishvili, Liudmila

2018-01-01

The eastern regions of Russia have a substantial potential for expansion of steaming coal production. The majority of coal deposits in the eastern regions are located close enough to the objects of the Asian super ring. The large coal reserves make it possible to consider it as a reliable fuel source for power plants for a long-term horizon. The coal reserves suitable for using at power plants of the Asian super ring are estimated in the paper by subject of the federation of the eastern regions for operating and new coal producers. The coal deposits of the eastern regions that are promising for the construction of power plants of the Asian super ring are presented. The paper describes both the coal deposits of the eastern regions that are considered in the projects for power plant construction and included in the program documents and the coal deposits that are not included in the program documents. The coal reserves of these deposits and the possible volumes of its production are estimated. The key qualitative coal characteristics of the deposits: heating value, and ash, sulfur, moisture content are presented. The mining-geological and hydrological conditions for deposit development are briefly characterized. The coals of the eastern regions are showed to contain valuable accompanying elements. It is noted that the creation of industrial clusters on the basis of the coal deposits is the most effective from the standpoints of the economy and ecology. The favorable and restraining factors in development of the described coal deposits are estimated.

Creep life prediction of super heater coils used in coal based thermal power plants subjected to fly ash erosion and oxide scale formation

Science.gov (United States)

Srinivasan, P.; Kushwaha, Shashank

2018-04-01

Super heater coils of the coal based thermal power plants and subjected to severe operating conditions from both steam side and gas side. Formation of oxide scale due to prolonged service lead to temperature raise of the tube and erosion due to fly ash present in the combusted gases leads to tube thinning. Both these factors lead to creep rupture of the coils much before the designed service life. Failure of super heater coils during service of the boiler leads to power loss and huge monitory loss to the power plants. An attempt is made to model the creep damage caused to the super heater coils using heat transfer analysis tube thinning due to erosive wear of the tubes. Combined effects of these parameters are taken into consideration to predict the life of the super heater coils. This model may be used to estimate the life of the coils operating under the severe operating conditions to prevent the unexpected failure of the coils.

Hydrogen storage for mixed wind-nuclear power plants in the context of a hydrogen economy

International Nuclear Information System (INIS)

Taljan, Gregor; Fowler, Michael; Canizares, Claudio; Verbic, Gregor

2008-01-01

A novel methodology for the economic evaluation of hydrogen production and storage for a mixed wind-nuclear power plant considering some new aspects such as residual heat and oxygen utilization is applied in this work. This analysis is completed in the context of a hydrogen economy and competitive electricity markets. The simulation of the operation of a combined nuclear-wind-hydrogen system is discussed first, where the selling and buying of electricity, the selling of excess hydrogen and oxygen, and the selling of heat are optimized to maximize profit to the energy producer. The simulation is performed in two phases: in a pre-dispatch phase, the system model is optimized to obtain optimal hydrogen charge levels for the given operational horizons. In the second phase, a real-time dispatch is carried out on an hourly basis to optimize the operation of the system as to maximize profits, following the hydrogen storage levels of the pre-dispatch phase. Based on the operation planning and dispatch results, an economic evaluation is performed to determine the feasibility of the proposed scheme for investment purposes; this evaluation is based on calculations of modified internal rates of return and net present values for a realistic scenario. The results of the present studies demonstrate the feasibility of a hydrogen storage and production system with oxygen and heat utilization for existent nuclear and wind power generation facilities. (author)

Hydrogen risk reduction in Nuclear power plant

International Nuclear Information System (INIS)

Movahed, M.A.; Travis, J.R.

1999-01-01

In case of a severe accident in a nuclear power plant with core melt and hydrogen production, the hydrogen risk is one of the main concerns. It may jeopardize the containment integrity due to violent deflagration that can lead to DDT (Deflagration Detonation Transient) or even detonation of proper hydrogen mitigation means are not available. The design of the EPR (European Pressurized water Reactor) Hydrogen mitigation and control system is based on the lumped parameter code WAVCO and the 3D code GASFLOW. The concept consists of recombiners and igniters to cope with all scenarios including those without steam. The system has been checked to avoid DDT by the 7λ criteria that's implemented in GASFLOW. Future analysis could deal with determining dynamic pressure loads, if appropriate, and some sensitivity studies to check the hydrogen control measures with respect to different source locations and mass flow rates. Also a conditional criterion for determining the likelihood of fast deflagration should be developed. (author)

Core design and fuel rod analyses of a super fast reactor with high power density

International Nuclear Information System (INIS)

Ju, Haitao; Cao, Liangzhi; Lu, Haoliang; Oka, Yoshiaki; Ikejiri, Satoshi; Ishiwatari, Yuki

2009-01-01

A Super Fast Reactor is a pressure-vessel type, fast spectrum SuperCritical Water Reactor (SCWR) that is presently researched in a Japanese project. One of the most important advantages of the Super Fast Reactor is the higher power density compared to the thermal spectrum SCWR, which reduces the capital cost. A preliminary core has an average power density of 158.8W/cc. In this paper, the principle of improving the average power density is studied and the core design is improved. After the sensitivity analyses on the fuel rod configurations, the fuel assembly configurations and the core configurations, an improved core with an average power density of 294.8W/cc is designed by 3-D neutronic/thermal-hydraulic coupled calculations. This power density is competitive with that of typical Liquid Metal Fast Breeder Reactors (LMFBR). In order to ensure the fuel rod integrity of this core design, the fuel rod behaviors on the normal operating condition are analyzed using FEMAXI-6 code. The power histories of each fuel rod are taken from the neutronics calculation results in the core design. The cladding surface temperature histories are taken from the thermal-hydraulic calculation results in the core design. Four types of the limiting fuel rods, with the Maximum Cladding Surface Temperature (MCST), Maximum Power Peak(MPP), Maximum Discharge Burnup(MDB) and Different Coolant Flow Pattern (DCFP), are chosen to cover all the fuel rods in the core. The available design range of the fuel rod design parameters, such as initial gas plenum pressure, gas plenum position, gas plenum length, grain size and gap size, are found out in order to satisfy the following design criteria: (1) Maximum fuel centerline temperature should be less than 1900degC. (2) Maximum cladding stress in circumstance direction should be less than 100MPa. (3) Pressure difference on the cladding should be less than 1/3 of buckling collapse pressure. (4) Cumulative damage faction (CDF) of the cladding should be

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

International Nuclear Information System (INIS)

Nakamura, Masayuki; Kodama, Hideo; Murashima, Masayasu

1977-01-01

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

Feasibility analysis of a hydrogen backup power system for Russian telecom market

Science.gov (United States)

Borzenko, V. I.; Dunikov, D. O.

2017-11-01

We performed feasibility analysis of 10 kW hydrogen backup power system (H2BS) consisting of a water electrolyzer, a metal hydride hydrogen storage and a fuel cell. Capital investments in H2BS are mostly determined by the costs of the PEM electrolyzer, the fuel cell and solid state hydrogen storage materials, for single unit or small series manufacture the cost of AB5-type intermetallic compound can reach 50% of total system cost. Today the capital investments in H2BS are 3 times higher than in conventional lead-acid system of the same capacity. Wide distribution of fuel cell hydrogen vehicles, development of hydrogen infrastructure, and mass production of hydrogen power systems will for sure lower capital investments in fuel cell backup power. Operational expenditures for H2BS is only 15% from the expenditures for lead acid systems, and after 4-5 years of exploitation the total cost of ownership will become lower than for batteries.

Composite type nuclear power system

International Nuclear Information System (INIS)

Nakamoto, Koichiro.

1993-01-01

The present invention realizes a high thermal efficiency by heating steams at the exit of a steam generator of a nuclear power plant to high temperature by a thermal super-heating boiler. That is, a thermal superheating boiler is disposed between the steam generator and a turbogenerator to heat steams from the steam generator and supply them to the turbogenerator. In this case, it may be possible that feedwater superheating boiler pipelines to the steam generator are caused to pass through the thermal superheating boiler so that they also have a performance of heating feedwater. If the system of the present invention is used, it is possible to conduct base load operation by nuclear power and a load following operation by controlling the thermal superheating boiler. Further, a hydrogen producing performance is applied to the thermal superheating boiler to produce hydrogen when electric power load is lowered. An internally sustaining type operation method can be conducted of burning hydrogen by the superheating boiler upon increased electric power load. As a result, a power generation system which has an excellent economical property and can easily cope with the load following operation can be attained. (I.S.)

Hydrogen considerations in light-water power reactons

International Nuclear Information System (INIS)

Keilholtz, G.W.

1976-02-01

A critical review of the literature now available on hydrogen considerations in light-water power reactors (LWRs) and a bibliography of that literature are presented. The subject matter includes mechanisms for the generation of hydrogen-oxygen mixtures, a description of the fundamental properties of such mixtures, and their spontaneous ignition in both static and dynamic systems. The limits for hydrogen flammability and flame propagation are examined in terms of the effects of pressure, temperature, and additives; the emphasis is on the effects of steam and water vapor. The containment systems for pressurized-water reactors (PWRs) and boiling-water reactors (BWRs) are compared, and methods to control hydrogen and oxygen under the conditions of both normal operation and postulated accidents are reviewed. It is concluded that hydrogen can be controlled so that serious complications from the production of hydrogen will not occur. The bibliography contains abstracts from the computerized files of the Nuclear Safety Information Center. Key-word, author, and permuted-title indexes are provided. The bibliography includes responses to questions asked by the U. S. Nuclear Regulatory Commission (NRC) which relate to hydrogen, as well as information on normal operations and postulated accidents including generation of hydrogen from core sprays. Other topics included in the ten sections of the bibliography are metal-water reactions, containment atmosphere, radiolytic gas, and recombiners

Impedance measurement and modelling of super-capacitors for railway applications

Energy Technology Data Exchange (ETDEWEB)

Hammar, A.; Chabas, J. [Societe Nationale des Chemins de fer Francais (SNCF), Dir. de la Recherche, 75 - Paris (France); Coquery, G.; Lallemand, R. [Institut National de Recherche sur les Transports et leur Securite (INRETS), Lab. des Technologies Nouvelles, 94 - Arcueil (France); Rojat, G.; Venet, P. [Lyon-1 Univ. Claude Bernard, CEGELY, 69 - Villeurbanne (France)

2004-07-01

Railways and electrical traction systems require high power rates to achieve their operating performances. Systems of power supply based on super-capacitors should offer high power density along with good energy efficiency and expected operating safety. We investigate general behaviours of super-capacitors with two powerful methods of analysis. The first is constant charge/discharge current at high level value (500 A), the second is impedance spectroscopy which leads to the acquisition of a set of parameters that are considered sufficient to describe general properties of super-capacitor, in particular the state of health and the available energy in any operating conditions. An electrical circuit model is defined for super-capacitors based on activated carbon and organic electrolyte. It takes into account the dependence of super-capacitor to voltage and current. The mixture of data of the two methods permits to obtain a representative model for power applications. Matlab/Simulink simulations are shown to verify the validity of the model. (authors)

Hydrogen-fuel-powered bell segments of biomimetic jellyfish

International Nuclear Information System (INIS)

Tadesse, Yonas; Villanueva, Alex; Priya, Shashank; Haines, Carter; Novitski, David; Baughman, Ray

2012-01-01

Artificial muscles powered by a renewable energy source are desired for joint articulation in bio-inspired autonomous systems. In this study, a robotic underwater vehicle, inspired by jellyfish, was designed to be actuated by a chemical fuel source. The fuel-powered muscles presented in this work comprise nano-platinum catalyst-coated multi-wall carbon nanotube (MWCNT) sheets, wrapped on the surface of nickel–titanium (NiTi) shape memory alloy (SMA). As a mixture of oxygen and hydrogen gases makes contact with the platinum, the resulting exothermic reaction activates the nickel–titanium (NiTi)-based SMA. The MWCNT sheets serve as a support for the platinum particles and enhance the heat transfer due to the high thermal conductivity between the composite and the SMA. A hydrogen and oxygen fuel source could potentially provide higher power density than electrical sources. Several vehicle designs were considered and a peripheral SMA configuration under the robotic bell was chosen as the best arrangement. Constitutive equations combined with thermodynamic modeling were developed to understand the influence of system parameters that affect the overall actuation behavior of the fuel-powered SMA. The model is based on the changes in entropy of the hydrogen and oxygen fuel on the composite actuator within a channel. The specific heat capacity is the dominant factor controlling the width of the strain for various pulse widths of fuel delivery. Both theoretical and experimental strains for different diameter (100 and 150 µm) SMA/MWCNT/Pt fuel-powered muscles with dead weight attached at the end exhibited the highest magnitude under 450 ms of fuel delivery within 1.6 mm diameter conduit size. Fuel-powered bell deformation of 13.5% was found to be comparable to that of electrically powered (29%) and natural jellyfish (42%). (paper)

Training for power plant personnel on hydrogen production and control

International Nuclear Information System (INIS)

Dickelman, G.J.

1982-01-01

It is the purpose of this paper to address the issue of training for power plant personnel in the area of hydrogen control. The authors experience in the training business indicates that most of the operations and engineering personnel have a very limited awareness of this phenomenon. Topics discussed in this paper include: 1) theory of hydrogen combustion kinetics; 2) incidents involving hydrogen combustion events; 3) normal operations interfacing with hydrogen; 4) accident conditions; and 5) mitigation schemes

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

Control of an innovative super-capacitor-powered shape-memory-alloy actuated accumulator for blowout preventer

Science.gov (United States)

Chen, Jian; Li, Peng; Song, Gangbing; Ren, Zhang

2017-01-01

The design of a super-capacitor-powered shape-memory-alloy (SMA) actuated accumulator for blowout preventer (BOP) presented in this paper featured several advantages over conventional hydraulic accumulators including instant large current drive, quick system response and elimination of need for the pressure conduits. However, the mechanical design introduced two challenges, the nonlinear nature of SMA actuators and the varying voltage provided by a super capacitor, for control system design. A cerebellar model articulation controller (CMAC) feedforward plus PID controller was developed with the aim of compensation for these adverse effects. Experiments were conducted on a scaled down model and experimental results show that precision control can be achieved with the proposed configurations and algorithms.

Sensor for Measuring Hydrogen Partial Pressure in Parabolic Trough Power Plant Expansion Tanks

Energy Technology Data Exchange (ETDEWEB)

Glatzmaier, Greg C.; Cooney, Daniel A.

2017-06-27

The National Renewable Energy Laboratory and Acciona Energy North America are working together to design and implement a process system that provides a permanent solution to the issue of hydrogen buildup at parabolic trough power plants. We are pursuing a method that selectively removes hydrogen from the expansion tanks that serve as reservoirs for the heat transfer fluid (HTF) that circulates in the collector field and power block components. Our modeling shows that removing hydrogen from the expansion tanks at a design rate reduces and maintains dissolved hydrogen in the circulating HTF to a selected target level. Our collaborative work consists of several tasks that are needed to advance this process concept to a development stage, where it is ready for implementation at a commercial power plant. Our main effort is to design and evaluate likely process-unit operations that remove hydrogen from the expansion tanks at a specified rate. Additionally, we designed and demonstrated a method and instrumentation to measure hydrogen partial pressure and concentration in the expansion-tank headspace gas. We measured hydrogen partial pressure in the headspace gas mixture using a palladium-alloy membrane, which is permeable exclusively to hydrogen. The membrane establishes a pure hydrogen gas phase that is in equilibrium with the hydrogen in the gas mixture. We designed and fabricated instrumentation, and demonstrated its effectiveness in measuring hydrogen partial pressures over a range of three orders of magnitude. Our goal is to install this instrument at the Nevada Solar One power plant and to demonstrate its effectiveness in measuring hydrogen levels in the expansion tanks under normal plant operating conditions.

Hydrogen in water-cooled nuclear power reactors

International Nuclear Information System (INIS)

1992-01-01

The Commission of the European Community (CEC) and the International Atomic Energy Agency (IAEA) decided in 1989 to update the state of the art concerning hydrogen in water cooled nuclear power reactors by commissioning a report which would review, all the available information to-date and make recommendations for the future. This joint report was prepared by committees formed by the IAEA and by the CEC. The aim of this report is to review the current understanding on the areas in which the research on hydrogen in LWR is conventionally presented, taking into account the results of the latest reported research developments. The main reactions through which hydrogen is produced are assessed together with their timings. An estimation of the amount of hydrogen produced by each reaction is given, in order to reckon their relative contribution to the hazard. An overview is then given of the state of knowledge of the most important phenomena taking place during its transport from the place of production and the phenomena which control the hydrogen combustion and the consequences of combustion under various conditions. Specific research work is recommended in each sector of the presented phenomena. The last topics reviewed in this report are the hydrogen detection and the prevent/mitigation of pressure and temperature loads on containment structures and structures and safety related equipment caused by hydrogen combustion

Pd/Ag coated fiber Bragg grating sensor for hydrogen monitoring in power transformers.

Science.gov (United States)

Ma, G M; Jiang, J; Li, C R; Song, H T; Luo, Y T; Wang, H B

2015-04-01

Compared with conventional DGA (dissolved gas analysis) method for on-line monitoring of power transformers, FBG (fiber Bragg grating) hydrogen sensor represents marked advantages over immunity to electromagnetic field, time-saving, and convenience to defect location. Thus, a novel FBG hydrogen sensor based on Pd/Ag (Palladium/Silver) along with polyimide composite film to measure dissolved hydrogen concentration in large power transformers is proposed in this article. With the help of Pd/Ag composite coating, the enhanced performance on mechanical strength and sensitivity is demonstrated, moreover, the response time and sensitivity influenced by oil temperature are solved by correction lines. Sensitivity measurement and temperature calibration of the specific hydrogen sensor have been done respectively in the lab. And experiment results show a high sensitivity of 0.055 pm/(μl/l) with instant response time about 0.4 h under the typical operating temperature of power transformers, which proves a potential utilization inside power transformers to monitor the health status by detecting the dissolved hydrogen concentration.

SuperB A High-Luminosity Asymmetric $e^+ e^-$ Super Flavour Factory : Conceptual Design Report

CERN Document Server

Bona, M.; Grauges Pous, E.; Colangelo, P.; De Fazio, F.; Palano, A.; Manghisoni, M.; Re, V.; Traversi, G.; Eigen, G.; Venturini, M.; Soni, N.; Bruschi, M.; De Castro, S.; Faccioli, P.; Gabrieli, A.; Giacobbe, B.; Semprini Cesare, N.; Spighi, R.; Villa, M.; Zoccoli, A.; Hearty, C.; McKenna, J.; Soni, A.; Khan, A.; Barniakov, A.Y.; Barniakov, M.Y.; Blinov, V.E.; Druzhinin, V.P.; Golubev, V.B.; Kononov, S.A.; Koop, I.A.; Kravchenko, E.A.; Levichev, E.B.; Nikitin, S.A.; Onuchin, A.P.; Piminov, P.A.; Serednyakov, S.I.; Shatilov, D.N.; Skovpen, Y.I.; Solodov, E.A.; Cheng, C.H.; Echenard, B.; Fang, F.; Hitlin, D.J.; Porter, F.C.; Asner, D.M.; Pham, T.N.; Fleischer, R.; Giudice, G.F.; Hurth, T.; Mangano, M.; Mancinelli, G.; Meadows, B.T.; Schwartz, A.J.; Sokoloff, M.D.; Soffer, A.; Beard, C.D.; Haas, T.; Mankel, R.; Hiller, G.; Ball, P.; Pappagallo, M.; Pennington, M.R.; Gradl, W.; Playfer, S.; Abada, A.; Becirevic, D.; Descotes-Genon, S.; Pene, O.; Andreotti, D.; Andreotti, M.; Bettoni, D.; Bozzi, C.; Calabresi, R.; Cecchi, A.; Cibinetto, G.; Franchini, P.; Luppi, E.; Negrini, M.; Petrella, A.; Piemontese, L.; Prencipe, E.; Santoro, V.; Stancari, G.; Anulli, F.; Baldini-Ferroli, R.; Biagini, M.E.; Boscolo, M.; Calcaterra, A.; Drago, A.; Finocchiaro, G.; Guiducci, S.; Isidori, G.; Pacetti, S.; Patteri, P.; Peruzzi, I.M.; Piccolo, M.; Preger, M.A.; Raimondi, P.; Rama, M.; Vaccarezza, C.; Zallo, A.; Zobov, M.; De Sangro, R.; Buzzo, A.; Lo Vetere, M.; Macri, M.; Monge, M.R.; Passaggio, S.; Patrignani, C.; Robutti, E.; Tosi, S.; Matias, J.; Panduro Vazquez, W.; Borzumati, F.; Eyges, V.; Prell, S.A.; Pedlar, T.K.; Korpar, S.; Pestonik, R.; Staric, M.; Neubert, M.; Denig, A.G.; Nierste, U.; Agoh, T.; Ohmi, K.; Ohnishi, Y.; Fry, J.R.; Touramanis, C.; Wolski, A.; Golob, B.; Krizan, P.; Flaecher, H.; Bevan, A.J.; Di Lodovico, F.; George, K.A.; Barlow, R.; Lafferty, G.; Jawahery, A.; Roberts, D.A.; Simi, G.; Patel, P.M.; Robertson, S.H.; Lazzaro, A.; Palombo, F.; Kaidalov, A.; Buras, A.J.; Tarantino, C.; Buchalla, G.; Sanda, A.I.; D'Ambrosio, G.; Ricciardi, G.; Bigi, I.; Jessop, C.P.; Losecco, J.M.; Honscheid, K.; Arnaud, N.; Chehab, R.; Fedala, Y.; Polci, F.; Roudeau, P.; Sordini, V.; Soskov, V.; Stocchi, A.; Variola, A.; Vivoli, A.; Wormser, G.; Zomer, F.; Bertolin, A.; Brugnera, R.; Gagliardi, N.; Gaz, A.; Margoni, M.; Morandin, M.; Posocco, M.; Rotondo, M.; Simonetto, F.; Stroili, R.; Bonneaud, G.R.; Lombardo, V.; Calderini, G.; Ratti, L.; Speziali, V.; Biasini, M.; Covarelli, R.; Manoni, E.; Servoli, L.; Angelini, C.; Batignani, G.; Bettarini, S.; Bosi, F.; Carpinelli, M.; Cenci, R.; Cervelli, A.; Dell'Orso, M.; Forti, F.; Giannetti, P.; Giorgi, M.; Lusiani, A.; Marchiori, G.; Massa, M.; Mazur, M.A.; Morsani, F.; Neri, N.; Paoloni, E.; Raffaelli, F.; Rizzo, G.; Walsh, J.; Braun, V.; Lenz, A.; Adams, G.S.; Danko, I.Z.; Baracchini, E.; Bellini, F.; Cavoto, G.; D'Orazio, A.; Del Re, D.; Di Marco, E.; Faccini, R.; Ferrarotto, F.; Gaspero, Mario; Jackson, P.; Martinelli, G.; Mazzoni, M.A.; Morganti, Silvio; Piredda, G.; Renga, F.; Silvestrini, L.; Voena, C.; Catani, L.; Di Ciaccio, A.; Messi, R.; Santovetti, E.; Satta, A.; Ciuchini, M.; Lubicz, V.; Wilson, F.F.; Godang, R.; Chen, X.; Liu, H.; Park, W.; Purohit, M.; Trivedi, A.; White, R.M.; Wilson, J.R.; Allen, M.T.; Aston, D.; Bartoldus, R.; Brodsky, S.J.; Cai, Y.; Coleman, J.; Convery, M.R.; DeBarger, S.; Dingfelder, J.C.; Dubois-Felsmann, G.P.; Ecklund, S.; Fisher, A.S.; Haller, G.; Heifets, S.A.; Kaminski, J.; Kelsey, M.H.; Kocian, M.L.; Leith, D.W.G.S.; Li, N.; Luitz, S.; Luth, V.; MacFarlane, D.; Messner, R.; Muller, D.R.; Nosochkov, Y.; Novokhatski, A.; Pivi, M.; Ratcliff, B.N.; Roodman, A.; Schwiening, J.; Seeman, J.; Snyder, A.; Sullivan, M.; Va'Vra, J.; Wienands, U.; Wisniewski, W.; Stoeck, H.; Cheng, H.Y.; Li, H.N.; Keum, Y.Y.; Gronau, M.; Grossman, Y.; Bianchi, F.; Gamba, D.; Gambino, P.; Marchetto, F.; Menichetti, Ezio A.; Mussa, R.; Pelliccioni, M.; Dalla Betta, G.F.; Bomben, M.; Bosisio, L.; Cartaro, C.; Lanceri, L.; Vitale, L.; Azzolini, V.; Bernabeu, J.; Lopez-March, N.; Martinez-Vidal, F.; Milanes, D.A.; Oyanguren, A.; Paradisi, P.; Pich, A.; Sanchis-Lozano, M.A.; Kowalewski, Robert V.; Roney, J.M.; Back, J.J.; Gershon, T.J.; Harrison, P.F.; Latham, T.E.; Mohanty, G.B.; Petrov, A.A.; Pierini, M.; INFN

2007-01-01

The physics objectives of SuperB, an asymmetric electron-positron collider with a luminosity above 10^36/cm^2/s are described, together with the conceptual design of a novel low emittance design that achieves this performance with wallplug power comparable to that of the current B Factories, and an upgraded detector capable of doing the physics in the SuperB environment.

EUROv Super Beam Studies

International Nuclear Information System (INIS)

Dracos, Marcos

2011-01-01

Neutrino Super Beams use conventional techniques to significantly increase the neutrino beam intensity compared to the present neutrino facilities. An essential part of these facilities is an intense proton driver producing a beam power higher than a MW. The protons hit a target able to accept the high proton beam intensity. The produced charged particles are focused by a system of magnetic horns towards the experiment detectors. The main challenge of these projects is to deal with the high beam intensity for many years. New high power neutrino facilities could be build at CERN profiting from an eventual construction of a high power proton driver. The European FP7 Design Study EUROv, among other neutrino beams, studies this Super Beam possibility. This paper will give the latest developments in this direction.

System Evaluation and Economic Analysis of a HTGR Powered High-Temperature Electrolysis Hydrogen Production Plant

International Nuclear Information System (INIS)

McKellar, Michael G.; Harvego, Edwin A.; Gandrik, Anastasia A.

2010-01-01

A design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production has been developed. The HTE plant is powered by a high-temperature gas-cooled reactor (HTGR) whose configuration and operating conditions are based on the latest design parameters planned for the Next Generation Nuclear Plant (NGNP). The current HTGR reference design specifies a reactor power of 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 322 C and 750 C, respectively. The power conversion unit will be a Rankine steam cycle with a power conversion efficiency of 40%. The reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes a steam-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The overall system thermal-to-hydrogen production efficiency (based on the higher heating value of the produced hydrogen) is 40.4% at a hydrogen production rate of 1.75 kg/s and an oxygen production rate of 13.8 kg/s. An economic analysis of this plant was performed with realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a cost of $3.67/kg of hydrogen assuming an internal rate of return, IRR, of 12% and a debt to equity ratio of 80%/20%. A second analysis shows that if the power cycle efficiency increases to 44.4%, the hydrogen production efficiency increases to 42.8% and the hydrogen and oxygen production rates are 1.85 kg/s and 14.6 kg/s respectively. At the higher power cycle efficiency and an IRR of 12% the cost of hydrogen production is $3.50/kg.

Lifespan estimation of seal welded super stainless steels for water condenser of nuclear power plants

Science.gov (United States)

Kim, Young Sik; Park, Sujin; Chang, Hyun Young

2014-01-01

When sea water was used as cooling water for water condenser of nuclear power plants, commercial stainless steels can not be applied because chloride concentration exceeds 20,000 ppm. There are many opinions for the materials selection of tube and tube sheets of a condenser. This work reviewed the application guide line of stainless steels for sea-water facilities and the estimation equations of lifespan were proposed from the analyses of both field data for sea water condenser and experimental results of corrosion. Empirical equations for lifespan estimation were derived from the pit initiation time and re-tubing time of stainless steel tubing in sea water condenser of nuclear power plants. The lifespan of seal-welded super austenitic stainless steel tube/tube sheet was calculated from these equations. Critical pitting temperature of seal-welded PRE 50 grade super stainless steel was evaluated as 60 °C. Using the proposed equation in engineering aspect, tube pitting corrosion time of seal-welded tube/tube sheet was calculated as 69.8 years and re-tubing time was estimated as 82.0 years.

Thermodynamic evaluation of geothermal energy powered hydrogen production by PEM water electrolysis

International Nuclear Information System (INIS)

Yilmaz, Ceyhun; Kanoglu, Mehmet

2014-01-01

Thermodynamic energy and exergy analysis of a PEM water electrolyzer driven by geothermal power for hydrogen production is performed. For this purpose, work is produced from a geothermal resource by means of the organic Rankine cycle; the resulting work is used as a work input for an electrolysis process; and electrolysis water is preheated by the waste geothermal water. The first and second-law based performance parameters are identified for the considered system and the system performance is evaluated. The effects of geothermal water and electrolysis temperatures on the amount of hydrogen production are studied and these parameters are found to be proportional to each other. We consider a geothermal resource at 160 °C available at a rate of 100 kg/s. Under realistic operating conditions, 3810 kW power can be produced in a binary geothermal power plant. The produced power is used for the electrolysis process. The electrolysis water can be preheated to 80 °C by the geothermal water leaving the power plant and hydrogen can be produced at a rate of 0.0340 kg/s. The energy and exergy efficiencies of the binary geothermal power plant are 11.4% and 45.1%, respectively. The corresponding efficiencies for the electrolysis system are 64.0% and 61.6%, respectively, and those for the overall system are 6.7% and 23.8%, respectively. - Highlights: • Thermodynamic analysis of hydrogen production by PEM electrolysis powered by geothermal energy. • Power is used for electrolyser; used geothermal water is for preheating electrolysis water. • Effect of geothermal water and electrolysis temperatures on the amount of hydrogen production. • Hydrogen can be produced at a rate of 0.0340 kg/s for a resource at 160 °C available at 100 kg/s. • Energy and exergy efficiencies of the overall system are 6.7% and 23.8%, respectively

Techno-economic analysis of an autonomous power system integrating hydrogen technology as energy storage medium

Energy Technology Data Exchange (ETDEWEB)

Tzamalis, G. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece); Zoulias, E.I.; Stamatakis, E.; Varkaraki, E. [Center for Renewable Energy Sources (CRES), RES and Hydrogen Technologies, 19th km Marathon Avenue, GR 19009 Pikermi (Greece); Lois, E.; Zannikos, F. [Laboratory of Fuels and Lubricants Technology, School of Chemical Engineering, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou Campus, 157 80 Athens (Greece)

2011-01-15

Two different options for the autonomous power supply of rural or/and remote buildings are examined in this study. The first one involves a PV - diesel based power system, while the second one integrates RES and hydrogen technologies for the development of a self - sustained power system. The main objective is the replacement of the diesel generator and a comparison between these two options for autonomous power supply. Model simulations of the two power systems before and after the replacement, an optimization of the component sizes and a techno - economic analysis have been performed for the purpose of this study. A sensitivity analysis taking into account future cost scenarios for hydrogen technologies is also presented. The results clearly show that the Cost of Energy Produced (COE) from the PV - hydrogen technologies power system is extremely higher than the PV - diesel power system. However, the adopted PV - hydrogen technologies power system reduces to zero the Green - House Gas (GHG) emissions. Moreover, the sensitivity analysis indicates that COE for the latter system can be further reduced by approximately 50% compared to its initial value. This could be achieved by reducing critical COE's parameters, such as PEM electrolyser and fuel cell capital costs. Hence, a possible reduction on the capital costs of hydrogen energy equipment in combination with emissions reduction mentioned above could make hydrogen - based power systems more competitive. (author)

A four-component Dirac theory of ionization of a hydrogen molecular ion in a super-intense laser field

International Nuclear Information System (INIS)

Faisal, F H M

2009-01-01

In this communication, a four-component Dirac theory of ionization of a hydrogen molecular ion, H + 2 , in a super-intense laser field is presented. Analytic expressions for the spin-specific as well as the total ionization currents emitted from the ground state of the ion are derived. The results are given for arbitrary intensity, frequency, wavenumber and polarization of the field, and for the up or down spin of the bound and ionized states of the electron. They also apply for the case of inner-shell ionization of analogous heavier diatomic molecular ions. The presence of molecular two-slit interference effect, first found in the non-relativistic case, the spin-flip ionization current, and an asymmetry of the up- and down-spin currents similar to that predicted in the atomic case, is found to hold for the present relativistic molecular ionic case as well. The possibility of controlling the spin of the dominant ionization current in any direction by simply selecting the handedness of a circularly polarized incident laser field is pointed out. Finally, we note that the present results obtained within the strong field 'KFR' ansatz open up the way for an analogous fully relativistic four-component treatment for ionization of polyatomic molecules and clusters in super-intense laser fields. (fast track communication)

Water leak detection in steam generator of SUPER PHENIX

International Nuclear Information System (INIS)

Brunet, M.; Garnaud, P.; Ghaleb, D.; Kong, N.

1988-01-01

With the intent of detecting water leaks inside steam generators, we developed a third system, called acoustic detector, to complement hydrogen detectors and rupture disks (burst disks). The role of the acoustic system is to enable rapid intervention in the event of a leak growing rapidly which could rupture neighbouring tubes. In such a case, the detectable flow rate of the leak varies from a few tens of g/s to a few hundred g/s. At the SUPER PHENIX, three teams work in [20-100 kHz] and CEA/STA* [50-300 kHz]. The simulation of water leaks in the steam generator by the argon injections performed to date at 50% of the rated power has shown promising results. An anomaly in the evolution of the background noise at more than 50% loading of one of the two instrumented steam generators would make difficult any extrapolation to full power behaviour. (author)

Super-capacitors fuel-cell hybrid electric vehicle optimization and control strategy development

International Nuclear Information System (INIS)

Paladini, Vanessa; Donateo, Teresa; De Risi, Arturo; Laforgia, Domenico

2007-01-01

In the last decades, due to emissions reduction policies, research focused on alternative powertrains among which hybrid electric vehicles (HEVs) powered by fuel cells are becoming an attractive solution. One of the main issues of these vehicles is the energy management in order to improve the overall fuel economy. The present investigation aims at identifying the best hybrid vehicle configuration and control strategy to reduce fuel consumption. The study focuses on a car powered by a fuel cell and equipped with two secondary energy storage devices: batteries and super-capacitors. To model the powertrain behavior an on purpose simulation program called ECoS has been developed in Matlab/Simulink environment. The fuel cell model is based on the Amphlett theory. The battery and the super-capacitor models account for charge/discharge efficiency. The analyzed powertrain is also equipped with an energy regeneration system to recover braking energy. The numerical optimization of vehicle configuration and control strategy of the hybrid electric vehicle has been carried out with a multi objective genetic algorithm. The goal of the optimization is the reduction of hydrogen consumption while sustaining the battery state of charge. By applying the algorithm to different driving cycles, several optimized configurations have been identified and discussed

Hydrogen as an energy carrier and its production by nuclear power

International Nuclear Information System (INIS)

1999-05-01

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

Hydrogen as an energy carrier and its production by nuclear power

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-05-01

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

Failure evaluation on a high-strength alloy SA213-T91 super heater tube of a power generation

Energy Technology Data Exchange (ETDEWEB)

Ahmad, J.; Purbolaksono, J.; Beng, L.C.; Ahmad, A. [University of Tenaga Nas, Kajang (Malaysia). Dept. of Mechanical Engineering

2010-07-01

This article presents failure investigation on a high-strength alloy SA213-T91 superheater tube. This failure is the first occurrence involving the material in Kapar Power Station Malaysia. The investigation includes visual inspections, hardness measurements, and microscopic examinations. The failed super-heater tube shows a wide open rupture with thin and blunt edges. Hardness readings on all the as-received tubes are used for estimating the operating metal temperature of the super-heater tubes. Microstructures of the failed tube show numerous creep cavities consisting of individual pores and chain of pores which form micro-and macro-cracks. The findings confirmed that the super-heater tube is failed by short-term overheating. Higher temperatures of the flue gas due to the inconsistent feeding of pulverized fuels into the burner is identified to cause overheating of the failed tube.

Dynamic behaviour of Li batteries in hydrogen fuel cell power trains

Science.gov (United States)

Veneri, O.; Migliardini, F.; Capasso, C.; Corbo, P.

A Li ion polymer battery pack for road vehicles (48 V, 20 Ah) was tested by charging/discharging tests at different current values, in order to evaluate its performance in comparison with a conventional Pb acid battery pack. The comparative analysis was also performed integrating the two storage systems in a hydrogen fuel cell power train for moped applications. The propulsion system comprised a fuel cell generator based on a 2.5 kW polymeric electrolyte membrane (PEM) stack, fuelled with compressed hydrogen, an electric drive of 1.8 kW as nominal power, of the same typology of that installed on commercial electric scooters (brushless electric machine and controlled bidirectional inverter). The power train was characterized making use of a test bench able to simulate the vehicle behaviour and road characteristics on driving cycles with different acceleration/deceleration rates and lengths. The power flows between fuel cell system, electric energy storage system and electric drive during the different cycles were analyzed, evidencing the effect of high battery currents on the vehicle driving range. The use of Li batteries in the fuel cell power train, adopting a range extender configuration, determined a hydrogen consumption lower than the correspondent Pb battery/fuel cell hybrid vehicle, with a major flexibility in the power management.

HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER

Energy Technology Data Exchange (ETDEWEB)

BROWN,LC; BESENBRUCH,GE; LENTSCH,RD; SCHULTZ,KR; FUNK,JF; PICKARD,PS; MARSHALL,AC; SHOWALTER,SK

2003-06-01

OAK B202 HIGH EFFICIENCY GENERATION OF HYDROGEN FUELS USING NUCLEAR POWER. Combustion of fossil fuels, used to power transportation, generate electricity, heat homes and fuel industry provides 86% of the world's energy. Drawbacks to fossil fuel utilization include limited supply, pollution, and carbon dioxide emissions. Carbon dioxide emissions, thought to be responsible for global warming, are now the subject of international treaties. Together, these drawbacks argue for the replacement of fossil fuels with a less-polluting potentially renewable primary energy such as nuclear energy. Conventional nuclear plants readily generate electric power but fossil fuels are firmly entrenched in the transportation sector. Hydrogen is an environmentally attractive transportation fuel that has the potential to displace fossil fuels. Hydrogen will be particularly advantageous when coupled with fuel cells. Fuel cells have higher efficiency than conventional battery/internal combustion engine combinations and do not produce nitrogen oxides during low-temperature operation. Contemporary hydrogen production is primarily based on fossil fuels and most specifically on natural gas. When hydrogen is produced using energy derived from fossil fuels, there is little or no environmental advantage. There is currently no large scale, cost-effective, environmentally attractive hydrogen production process available for commercialization, nor has such a process been identified. The objective of this work is to find an economically feasible process for the production of hydrogen, by nuclear means, using an advanced high-temperature nuclear reactor as the primary energy source. Hydrogen production by thermochemical water-splitting (Appendix A), a chemical process that accomplishes the decomposition of water into hydrogen and oxygen using only heat or, in the case of a hybrid thermochemical process, by a combination of heat and electrolysis, could meet these goals. Hydrogen produced from

Hydrogen consumption and power density in a co-flow planar SOFC

Energy Technology Data Exchange (ETDEWEB)

Ben Moussa, Hocine; Zitouni, Bariza [Laboratoire d' etude des systemes energetiques industriels (LESEI), Universite de Batna, Batna (Algeria); Oulmi, Kafia [Laboratoire de chimie et de chimie de l' environnement, Universite de Batna, Batna (Algeria); Mahmah, Bouziane; Belhamel, Maiouf [CDER, BP. 62 Route de l' Observatoire. Bouzareah. Alger (Algeria); Mandin, Philippe [Centre de Developpement des Energies Renouvelables (CDER), LECA, UMR 7575 CNRS-ENSCP Paris 6 (France)

2009-06-15

In the present work, power density and hydrogen consumption in a co-flow planar solid oxide fuel cell (SOFC) are studied according to the inlet functional parameters; such as the operational temperature, the operational pressure, the flow rates and the mass fractions of the species. Furthermore, the effect of the cell size is investigated. The results of a zero and a one-dimensional numerical electro-dynamic model predict the remaining quantity of the fed hydrogen at the output of the anode flow channel. The remaining hydrogen quantities and the SOFC's power density obtained are discussed as a function of the inlet functional parameters, the geometrical configuration of the cell and several operating cell voltages values. (author)

Proceedings of a Canadian Hydrogen Association workshop in support of the transition to the hydrogen age : Greening the fleet : the status of hydrogen-powered vehicles for fleet applications

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-07-01

The Canadian Hydrogen Association (CHA) endorses hydrogen as an energy carrier and promotes the development of a supporting hydrogen infrastructure. It promotes the research, development and commercialization of innovative ways to accelerate the application of hydrogen technologies to reduce greenhouse gas emissions. The presentations at this conference described new technologies and the companies that are developing hydrogen-powered vehicles, including hybrid-electric powered vehicles for fleet application. Some international activities were also covered, including lessons learned from the California experience and European fuel cell fleets. The benefits of fuel cell hybrids were highlighted along with methods to overcome the barriers to the introduction of new vehicle fuels. A review of current and future hydrogen supply infrastructure systems was also provided. The conference featured 14 presentations, of which 2 have been catalogued separately for inclusion in this database. refs., tabs., figs.

Basic tuning of hydrogen powered car and artificial intelligent prediction of hydrogen engine characteristics

Energy Technology Data Exchange (ETDEWEB)

Ho, Tien [School of Engineering, University of Tasmania, GPO Box 252-65, Hobart, Tasmania, 7001 (Australia); Karri, Vishy [Australian College of Kuwait, P.O. Box 1411, Safat 13015 (Kuwait)

2010-09-15

Many studies of renewable energy have shown hydrogen is one of the major green energy in the future. This has lead to the development of many automotive application of using hydrogen as a fuel especially in internal combustion engine. Nonetheless, there has been a slow growth and less knowledge details in building up the prototype and control methodology of the hydrogen internal combustion engine. In this paper, The Toyota Corolla 4 cylinder, 1.8l engine running on petrol was systematically modified in such a way that it could be operated on either gasoline or hydrogen at the choice of the driver. Within the scope of this project, several ancillary instruments such as a new inlet manifold, hydrogen fuel injection, storage system and leak detection safety system were implemented. Attention is directed towards special characteristics related to the basic tuning of hydrogen engine such as: air to fuel ratio operating conditions, ignition timing and injection timing in terms of different engine speed and throttle position. Based on the experimental data, a suite of neural network models were tested to accurately predict the effect of different engine operating conditions (speed and throttle position) on the hydrogen powered car engine characteristics. Predictions were found to be {+-}3% to the experimental values for all of case studies. This work provided better understanding of the effect of hydrogen engine characteristic parameters on different engine operating conditions. (author)

Separation of gaseous hydrogen from a water-hydrogen mixture in a fuel cell power system operating in a weightless environment

Science.gov (United States)

Romanowski, William E. (Inventor); Suljak, George T. (Inventor)

1989-01-01

A fuel cell power system for use in a weightless environment, such as in space, includes a device for removing water from a water-hydrogen mixture condensed from the exhaust from the fuel cell power section of the system. Water is removed from the mixture in a centrifugal separator, and is fed into a holding, pressure operated water discharge valve via a Pitot tube. Entrained nondissolved hydrogen is removed from the Pitot tube by a bleed orifice in the Pitot tube before the water reaches the water discharge valve. Water discharged from the valve thus has a substantially reduced hydrogen content.

A synergetic use of hydrogen and fuel cells in human spaceflight power systems

Science.gov (United States)

Belz, S.

2016-04-01

Hydrogen is very flexible in different fields of application of energy conversion. It can be generated by water electrolysis. Stored in tanks it is available for re-electrification by fuel cells. But it is not only the power system, which benefits from use of hydrogen, but also the life support system, which can contain hydrogen consuming technologies for recycling management (e.g. carbon dioxide removal and waste combustion processes). This paper points out various fields of hydrogen use in a human spaceflight system. Depending on mission scenarios, shadow phases, and the need of energy storage, regenerative fuel cell systems can be more efficient than secondary batteries. Here, different power storage concepts are compared by equivalent system mass calculation, thus including impact in the peripheral structure (volume, thermal management, etc.) on the space system. It is also focused on the technical integration aspect, e.g. which peripheral components have to be adapted when hydrogen is also used for life support technologies and what system mass benefit can be expected. Finally, a recommendation is given for the following development steps for a synergetic use of hydrogen and fuel cells in human spaceflight power systems.

Production price of hydrogen from grid connected electrolysis in a power market with high wind penetration

International Nuclear Information System (INIS)

Joergensen, Claus; Ropenus, Stephanie

2008-01-01

In liberalized power markets, there are significant power price fluctuations due to independently varying changes in demand and supply, the latter being substantial in systems with high wind power penetration. In such systems, hydrogen production by grid connected electrolysis can be cost optimized by operating an electrolyzer part time. This paper presents a study on the minimization of the hydrogen production price and its dependence on estimated power price fluctuations. The calculation of power price fluctuations is based on a parameterization of existing data on wind power production, power consumption and power price evolution in the West Danish power market area. The price for hydrogen is derived as a function of the optimal electrolyzer operation hours per year for four different wind penetration scenarios. It is found to amount to 0.41-0.45 EUR/Nm 3 . The study further discusses the hydrogen price sensitivity towards investment costs and the contribution from non-wind power sources. (author)

Production price of hydrogen from grid connected electrolysis in a power market with high wind penetration

Energy Technology Data Exchange (ETDEWEB)

Joergensen, Claus [Materials Research Department, Risoe National Laboratory for Sustainable Energy, Technical University of Denmark, P.O. Box 49, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Ropenus, Stephanie [Systems Analysis Department, Risoe National Laboratory for Sustainable Energy, Technical University of Denmark, P.O. Box 49, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)

2008-10-15

In liberalized power markets, there are significant power price fluctuations due to independently varying changes in demand and supply, the latter being substantial in systems with high wind power penetration. In such systems, hydrogen production by grid connected electrolysis can be cost optimized by operating an electrolyzer part time. This paper presents a study on the minimization of the hydrogen production price and its dependence on estimated power price fluctuations. The calculation of power price fluctuations is based on a parameterization of existing data on wind power production, power consumption and power price evolution in the West Danish power market area. The price for hydrogen is derived as a function of the optimal electrolyzer operation hours per year for four different wind penetration scenarios. It is found to amount to 0.41-0.45 EUR/Nm{sup 3}. The study further discusses the hydrogen price sensitivity towards investment costs and the contribution from non-wind power sources. (author)

Production price of hydrogen from grid connected electrolysis in a power market with high wind penetration.

Energy Technology Data Exchange (ETDEWEB)

Joergensen, Claus [Materials Research Department, Risoe National Laboratory for Sustainable Energy, Technical University of Denmark, P.O. Box 49, Frederiksborgvej 399, DK-4000 Roskilde (Denmark); Ropenus, Stephanie [Systems Analysis Department, Risoe National Laboratory for Sustainable Energy, Technical University of Denmark, P.O. Box 49, Frederiksborgvej 399, DK-4000 Roskilde (Denmark)

2008-10-15

In liberalized power markets, there are significant power price fluctuations due to independently varying changes in demand and supply, the latter being substantial in systems with high wind power penetration. In such systems, hydrogen production by grid connected electrolysis can be cost optimized by operating an electrolyzer part time. This paper presents a study on the minimization of the hydrogen production price and its dependence on estimated power price fluctuations. The calculation of power price fluctuations is based on a parameterization of existing data on wind power production, power consumption and power price evolution in the West Danish power market area. The price for hydrogen is derived as a function of the optimal electrolyzer operation hours per year for four different wind penetration scenarios. It is found to amount to 0.41-0.45 EUR/Nm{sup 3}. The study further discusses the hydrogen price sensitivity towards investment costs and the contribution from non-wind power sources. (author)

On the hydrogen atom via Wigner-Heisenberg algebra

International Nuclear Information System (INIS)

Rodrigues, R. de Lima . Unidade Academica de Educacao.

2008-01-01

We extend the usual Kustaanheimo-Stiefel 4D → 3D mapping to study and discuss a constrained super-Wigner oscillator in four dimensions. We show that the physical hydrogen atom is the system that emerges in the bosonic sector of the mapped super 3D system. (author)

Super differential forms on super Riemann surfaces

International Nuclear Information System (INIS)

Konisi, Gaku; Takahasi, Wataru; Saito, Takesi.

1994-01-01

Line integral on the super Riemann surface is discussed. A 'super differential operator' which possesses both properties of differential and of differential operator is proposed. With this 'super differential operator' a new theory of differential form on the super Riemann surface is constructed. We call 'the new differentials on the super Riemann surface' 'the super differentials'. As the applications of our theory, the existency theorems of singular 'super differentials' such as 'super abelian differentials of the 3rd kind' and of a super projective connection are examined. (author)

A novel multiple super junction power device structure with low specific on-resistance

International Nuclear Information System (INIS)

Zhu Hui; Li Haiou; Li Qi; Huang Yuanhao; Xu Xiaoning; Zhao Hailiang

2014-01-01

A novel multiple super junction (MSJ) LDMOS power device is proposed to decrease R on due to lateral and vertical interactions between the N-pillar and P-pillar. In the studied device: multiple layers of SJ are introduced oppositely under surface SJ; when compared with 2D-depleting of the conventional super junction (CSJ), a 3D-depleted effect is formed in the MSJ thanks to vertical electric field modulation; and, current distribution is improved by deep drain, which increases the drift doping concentration and results in a lower on-resistance. The high electric field around the drain region by substrate-assisted depleted effect is reduced due to the charge balance result from the electric field shielding effect of the bottom SJ, which causes the uniform electric field in the drift region and the high breakdown voltage. The numerical simulation results indicate that the specific on-resistance of the MSJ device is reduced by 42% compared with that of CSJ device, while maintaining a high breakdown voltage; the cell pitch of the device is 12 μm. (semiconductor devices)

A polymer electrolyte fuel cell stack for stationary power generation from hydrogen fuel

Energy Technology Data Exchange (ETDEWEB)

Gottesfeld, S. [Los Alamos National Lab., NM (United States)

1995-09-01

The fuel cell is the most efficient device for the conversion of hydrogen fuel to electric power. As such, the fuel cell represents a key element in efforts to demonstrate and implement hydrogen fuel utilization for electric power generation. The low temperature, polymer electrolyte membrane fuel cell (PEMFC) has recently been identified as an attractive option for stationary power generation, based on the relatively simple and benign materials employed, the zero-emission character of the device, and the expected high power density, high reliability and low cost. However, a PEMFC stack fueled by hydrogen with the combined properties of low cost, high performance and high reliability has not yet been demonstrated. Demonstration of such a stack will remove a significant barrier to implementation of this advanced technology for electric power generation from hydrogen. Work done in the past at LANL on the development of components and materials, particularly on advanced membrane/electrode assemblies (MEAs), has contributed significantly to the capability to demonstrate in the foreseeable future a PEMFC stack with the combined characteristics described above. A joint effort between LANL and an industrial stack manufacturer will result in the demonstration of such a fuel cell stack for stationary power generation. The stack could operate on hydrogen fuel derived from either natural gas or from renewable sources. The technical plan includes collaboration with a stack manufacturer (CRADA). It stresses the special requirements from a PEMFC in stationary power generation, particularly maximization of the energy conversion efficiency, extension of useful life to the 10 hours time scale and tolerance to impurities from the reforming of natural gas.

A flexible super-capacitive solid-state power supply for miniature implantable medical devices.

Science.gov (United States)

Meng, Chuizhou; Gall, Oren Z; Irazoqui, Pedro P

2013-12-01

We present a high-energy local power supply based on a flexible and solid-state supercapacitor for miniature wireless implantable medical devices. Wireless radio-frequency (RF) powering recharges the supercapacitor through an antenna with an RF rectifier. A power management circuit for the super-capacitive system includes a boost converter to increase the breakdown voltage required for powering device circuits, and a parallel conventional capacitor as an intermediate power source to deliver current spikes during high current transients (e.g., wireless data transmission). The supercapacitor has an extremely high area capacitance of ~1.3 mF/mm(2), and is in the novel form of a 100 μm-thick thin film with the merit of mechanical flexibility and a tailorable size down to 1 mm(2) to meet various clinical dimension requirements. We experimentally demonstrate that after fully recharging the capacitor with an external RF powering source, the supercapacitor-based local power supply runs a full system for electromyogram (EMG) recording that consumes ~670 μW with wireless-data-transmission functionality for a period of ~1 s in the absence of additional RF powering. Since the quality of wireless powering for implantable devices is sensitive to the position of those devices within the RF electromagnetic field, this high-energy local power supply plays a crucial role in providing continuous and reliable power for medical device operations.

Super compacting of drums with dry solid radioactive waste in the nuclear power plant of Laguna Verde;Super compactacion de bidones con desecho radiactivo solido seco en la central nucleo electrica Laguna Verde

Energy Technology Data Exchange (ETDEWEB)

Ramirez G, R.; Lara H, M. A.; Cabrera Ll, M.; Verdalet de la Torre, O., E-mail: marco.lara@cfe.gob.m [Comision Federal de Electricidad, Central Nucleoelectrica de Laguna Verde, Carretera Nautla-Cardel Km. 42.5, Alto Lucero, Veracruz (Mexico)

2009-10-15

The nuclear power plant of Laguna Verde located in the Gulf of Mexico, completes in this 2009, nineteen years to produce by nuclear means 4.78% of the electric power that Mexico requires daily. During this time, the Unit 1 has generated more of 88.85 million mega watt-hour and the Unit 2 more of 69.48 million mega watt-hour with an availability average of 83.55%. Derived of their operation cycles, the nuclear power plant has generated (as any other installation of its type) radioactive wastes of low activity that at the moment are temporarily stored in the site. Due to the life cycle of the nuclear power plant, actually has become necessary to begin a project series focused to continue guaranteeing the storage of these wastes, guarantee that is a license requirement for the operation of this nuclear installation before the National Commission of Nuclear Security and Safeguards. The Federal Commission of Electricity beginning a project that allows continue guaranteeing space of sufficient storage for the wastes that the nuclear power plant of Laguna Verde could generate for the rest of its useful life, this project consisted on a process of physical volume reduction of dry solid radioactive wastes denominated super compacting, it has made possible to reduce the volume that these wastes occupy in the temporary storage noted Dry Solid Radioactive Wastes Deposit located inside the site that occupies the nuclear power plant of Laguna Verde. This work presents the super compacting results, as well as a description of the realization of this task until concluding with the super compacting of 5,854 drums with dry solid radioactive waste of low activity. We will enunciate which were the radiological controls that the Department of Radiological Protection of the nuclear power plant of Laguna Verde applied to this work that was realized for first time in Mexico and the nuclear power plant. (Author)

Powering a Home with Just 25 Watts of Solar PV. Super-Efficient Appliances Can Enable Expanded Off-Grid Energy Service Using Small Solar Power Systems

Energy Technology Data Exchange (ETDEWEB)

Phadke, Amol A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Jacobson, Arne [Schatz Energy Research Center, Arcata, CA (United States); Park, Won Young [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Lee, Ga Rick [Schatz Energy Research Center, Arcata, CA (United States); Alstone, Peter [Univ. of California, Berkeley, CA (United States); Khare, Amit [Schatz Energy Research Center, Arcata, CA (United States)

2015-04-01

Highly efficient direct current (DC) appliances have the potential to dramatically increase the affordability of off-grid solar power systems used for rural electrification in developing countries by reducing the size of the systems required. For example, the combined power requirement of a highly efficient color TV, four DC light emitting diode (LED) lamps, a mobile phone charger, and a radio is approximately 18 watts and can be supported by a small solar power system (at 27 watts peak, Wp). Price declines and efficiency advances in LED technology are already enabling rapidly increased use of small off-grid lighting systems in Africa and Asia. Similar progress is also possible for larger household-scale solar home systems that power appliances such as lights, TVs, fans, radios, and mobile phones. When super-efficient appliances are used, the total cost of solar home systems and their associated appliances can be reduced by as much as 50%. The results vary according to the appliances used with the system. These findings have critical relevance for efforts to provide modern energy services to the 1.2 billion people worldwide without access to the electrical grid and one billion more with unreliable access. However, policy and market support are needed to realize rapid adoption of super-efficient appliances.

On the Potential of Hydrogen-Powered Hydraulic Pumps for Soft Robotics.

Science.gov (United States)

Desbiens, Alexandre B; Bigué, Jean-Philippe Lucking; Véronneau, Catherine; Masson, Patrice; Iagnemma, Karl; Plante, Jean-Sébastien

2017-12-01

To perform untethered operations, soft robots require mesoscale power units (10-1000 W) with high energy densities. In this perspective, air-breathing combustion offers an interesting alternative to battery-powered systems, provided sufficient overall energy conversion efficiency can be reached. Implementing efficient air-breathing combustion in mesoscale soft robots is notoriously difficult, however, as it requires optimization of very small combustion actuators and simultaneous minimization of fluidic (e.g., hydraulic) losses, which are both inversely impacted by actuations speeds. To overcome such challenges, this article proposes and evaluates the potential of hydrogen-powered, hydraulic free-piston pump architecture. Experimental data, taken from two combustion-driven prototypes, reveal (1) the fundamental role of using hydrogen as the source of fuel to reduce heat losses, (2) the significant impact of compression ratio, equivalence ratio, and surface-to-volume ratio on energy conversion efficiency, and (3) the importance of load matching between combustion and fluidic transmission. In this work, a small-bore combustion actuator demonstrated a 20% efficiency and a net mean output power of 26 W, while a big-bore combustion actuator reached a substantially higher efficiency of 35% and a net mean output power of 197 W. Using the small-bore combustion actuator, the hydrogen-powered, hydraulic free-piston pump provided a 4.6% overall efficiency for a 2.34 W net mean output power, thus underlying the potential of the approach for mesoscale soft robotic applications.

Study the feasibility of hydrogen assisted renewable power for off-grid communities

International Nuclear Information System (INIS)

Wu, S.H.; Fleetwood, M.; Roberston, R.; Nielsen, N.

2004-01-01

Most Renewable energy sources lack the controllability and availability of conventional fossil fuel-based energy sources and therefore cannot meet load requirements of a community without a backup or storage system. The advances of hydrogen technologies enable these renewable energy options to supply power to remote communities relying on independent sources of electrical and other energy. The hydrogen assisted renewable power (HARP) concept promises to make renewable energy more practical and mainstream through the use of hydrogen based electrical generation systems. The study herein is the first of a multiphase project to investigate the benefits of HARP as an environmentally friendly replacement for diesel in the supply of electricity to off-grid communities and analyse its feasibility and suitability as a back-up power supply. A small-scale pilot project was selected and this study assesses the major elements of a plant required to integrate electrical generation system, hydrogen storage and hydrogen generation into a renewable energy generation system. Based on the available renewable energy profiles, a simulation model was developed to assist in selecting, integrating, and evaluating various configurations and operational scenarios. This paper describes the components of the proposed HARP system as well as its cost, benefits and opportunities for other applications. (author)

Economic Analysis of a Nuclear Reactor Powered High-Temperature Electrolysis Hydrogen Production Plant

International Nuclear Information System (INIS)

E. A. Harvego; M. G. McKellar; M. S. Sohal; J. E. O'Brien; J. S. Herring

2008-01-01

A reference design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production was developed to provide a basis for comparing the HTE concept with other hydrogen production concepts. The reference plant design is driven by a high-temperature helium-cooled nuclear reactor coupled to a direct Brayton power cycle. The reference design reactor power is 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 540 C and 900 C, respectively. The electrolysis unit used to produce hydrogen includes 4,009,177 cells with a per-cell active area of 225 cm2. The optimized design for the reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes an air-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The inlet air for the air-sweep system is compressed to the system operating pressure of 5.0 MPa in a four-stage compressor with intercooling. The alternating-current, AC, to direct-current, DC, conversion efficiency is 96%. The overall system thermal-to-hydrogen production efficiency (based on the lower heating value of the produced hydrogen) is 47.12% at a hydrogen production rate of 2.356 kg/s. An economic analysis of this plant was performed using the standardized H2A Analysis Methodology developed by the Department of Energy (DOE) Hydrogen Program, and using realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a competitive cost. A cost of $3.23/kg of hydrogen was calculated assuming an internal rate of return of 10%

The application of CFD to hydrogen risk analysis in nuclear power plants

International Nuclear Information System (INIS)

Wang Hui; Han Xu; Chang Meng; Wang Xiaofeng; Wang Shuguo; Lu Xinhua; Wu Lin

2013-01-01

Status of the hydrogen risk analysis method is systemically summarized in this paper and the advantages and limits of CFD (Computational Fluid Dynamic) in hydrogen risk analysis is discussed. The international experimental programs on the CFD hydrogen risk analysis are introduced in this paper. The application of CFD to nuclear power plant (NPP) hydrogen risk analysis is introduced in detail by taking EPR and Ling'ao NPP for example. In these bases, the CFD development prospect of hydrogen risk analysis is also summarized in this paper. (authors)

Study about hydrogen and methanation as power surplus valorization process

International Nuclear Information System (INIS)

2014-09-01

The purpose of this study is to examine the use of technologies that allow converting power into gas as ways of providing added value to power surpluses. In the Anglo-Saxon world, and in numerous other countries, this concept is known as Power-to-Gas (PtG or P2G). The massive integration of fluctuating renewable energy sources ((wind and photovoltaic principally) into electricity systems implies more and more time periods during which production will exceed consumption. The volumes at stake could surpass the conventional capacities of flexibility and storage of the electricity system: the conversion into another energy carrier therefore appears as a solution for giving value to these surpluses. As the basic technology of Power-to-Gas, electrolysis converts electrical energy into chemical energy in the form of hydrogen gas (H2), by separating molecules of water (H 2 O). The gas produced can be used on-site in different manners, for example by a manufacturer for it's own process needs or by a filling station for hydrogen-fuelled vehicles (fuel-cell motorisation), or it can be stored locally for being later converted back into power through a fuel-cell. However it can also be directly injected into the gas distribution or transmission networks, thus creating a coupling of various energy networks and carriers: in this way the possibilities to create added-value from power surpluses are significantly increased and diversified both in terms of final use as well as across a scope of time and space. The development of Power-to-Gas can be summarized in three key steps. In the short to mid-term, hydrogen represents, when incorporated into the gas network in limited proportions (a few %) and/or used directly in some niche markets (particularly via fuel cells) a way to provide added value to substantial renewable electricity surpluses.. In the longer term, a transition toward synthetic methane production would allow to overcome all technical barriers linked with gas

Research on High Sensitive D-Shaped FBG Hydrogen Sensors in Power Transformer Oil.

Science.gov (United States)

Luo, Ying-Ting; Wang, Hong-Bin; Ma, Guo-Ming; Song, Hong-Tu; Li, Chengrong; Jiang, Jun

2016-10-04

Dissolved hydrogen is a symbol gas decomposed by power transformer oil for electrical faults such as overheat or partial discharges. A novel D-shaped fiber Bragg grating (D-FBG) sensor is herein proposed and was fabricated with magnetron sputtering to measure the dissolved hydrogen concentration in power transformer oil in this paper. Different from the RI (refractive index)-based effect, D-FBG in this case is sensitive to curvature caused by stress from sensing coating, leading to Bragg wavelength shifts accordingly. The relationship between the D-FBG wavelength shift and dissolved hydrogen concentration in oil was measured experimentally in the laboratory. The detected sensitivity could be as high as 1.96 μL/L at every 1-pm wavelength shift. The results proved that a simple, polished FBG-based hydrogen sensor provides a linear measuring characteristic in the range of low hydrogen concentrations in transformer oil. Moreover, the stable hydrogen sensing performance was investigated by X-ray diffraction analysis.

Research on High Sensitive D-Shaped FBG Hydrogen Sensors in Power Transformer Oil

Directory of Open Access Journals (Sweden)

Ying-Ting Luo

2016-10-01

Full Text Available Dissolved hydrogen is a symbol gas decomposed by power transformer oil for electrical faults such as overheat or partial discharges. A novel D-shaped fiber Bragg grating (D-FBG sensor is herein proposed and was fabricated with magnetron sputtering to measure the dissolved hydrogen concentration in power transformer oil in this paper. Different from the RI (refractive index-based effect, D-FBG in this case is sensitive to curvature caused by stress from sensing coating, leading to Bragg wavelength shifts accordingly. The relationship between the D-FBG wavelength shift and dissolved hydrogen concentration in oil was measured experimentally in the laboratory. The detected sensitivity could be as high as 1.96 μL/L at every 1-pm wavelength shift. The results proved that a simple, polished FBG-based hydrogen sensor provides a linear measuring characteristic in the range of low hydrogen concentrations in transformer oil. Moreover, the stable hydrogen sensing performance was investigated by X-ray diffraction analysis.

Progress in scale-up of second-generation high-temperature superconductors at SuperPower Inc

International Nuclear Information System (INIS)

Xie, Y.-Y.; Knoll, A.; Chen, Y.; Li, Y.; Xiong, X.; Qiao, Y.; Hou, P.; Reeves, J.; Salagaj, T.; Lenseth, K.; Civale, L.; Maiorov, B.; Iwasa, Y.; Solovyov, V.; Suenaga, M.; Cheggour, N.; Clickner, C.; Ekin, J.W.; Weber, C.; Selvamanickam, V.

2005-01-01

SuperPower is focused on scaling up second-generation (2-G) high-temperature superconductor (HTS) technology to pilot-scale manufacturing. The emphasis of this program is to develop R and D solutions for scale-up issues in pilot-scale operations to lay the foundation for a framework for large-scale manufacturing. Throughput continues to be increased in all process steps including substrate polishing, buffer and HTS deposition. 2-G HTS conductors have been produced in lengths up to 100 m. Process optimization with valuable information provided by several unique process control and quality-control tools has yielded performances of 6000-7000 A m (77 K, 0 T) in 50-100 m lengths using two HTS fabrication processes: metal organic chemical vapor deposition (MOCVD) and pulsed laser deposition (PLD). Major progress has been made towards the development of practical conductor configurations. Modifications to the HTS fabrication process have resulted in enhanced performance in magnetic fields. Industrial slitting and electroplating processes have been successfully adopted to fabricate tapes in width of 4 mm and with copper stabilizer for cable and coil applications. SuperPower's conductor configuration has yielded excellent mechanical properties and overcurrent carrying capability. Over 60 m of such practical conductors with critical current over 100 A/cm-width have been delivered to Sumitomo Electric Industries, Ltd. for prototype cable construction

Progress in scale-up of second-generation high-temperature superconductors at SuperPower Inc

Energy Technology Data Exchange (ETDEWEB)

Xie, Y.-Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States)]. E-mail: yxie@igc.com; Knoll, A. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Chen, Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Li, Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Xiong, X. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Qiao, Y. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Hou, P. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Reeves, J. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Salagaj, T. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Lenseth, K. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Civale, L. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Maiorov, B. [Los Alamos National Laboratory, Los Alamos, NM 87545 (United States); Iwasa, Y. [Massachusetts Institute of Technology, Cambridge, MA 02139 (United States); Solovyov, V. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Suenaga, M. [Brookhaven National Laboratory, Upton, NY 11973 (United States); Cheggour, N. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Clickner, C. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Ekin, J.W. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Weber, C. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States); Selvamanickam, V. [SuperPower Inc., 450 Duane Ave., Schenectady, NY 12304 (United States)

2005-10-01

SuperPower is focused on scaling up second-generation (2-G) high-temperature superconductor (HTS) technology to pilot-scale manufacturing. The emphasis of this program is to develop R and D solutions for scale-up issues in pilot-scale operations to lay the foundation for a framework for large-scale manufacturing. Throughput continues to be increased in all process steps including substrate polishing, buffer and HTS deposition. 2-G HTS conductors have been produced in lengths up to 100 m. Process optimization with valuable information provided by several unique process control and quality-control tools has yielded performances of 6000-7000 A m (77 K, 0 T) in 50-100 m lengths using two HTS fabrication processes: metal organic chemical vapor deposition (MOCVD) and pulsed laser deposition (PLD). Major progress has been made towards the development of practical conductor configurations. Modifications to the HTS fabrication process have resulted in enhanced performance in magnetic fields. Industrial slitting and electroplating processes have been successfully adopted to fabricate tapes in width of 4 mm and with copper stabilizer for cable and coil applications. SuperPower's conductor configuration has yielded excellent mechanical properties and overcurrent carrying capability. Over 60 m of such practical conductors with critical current over 100 A/cm-width have been delivered to Sumitomo Electric Industries, Ltd. for prototype cable construction.

Metallic hydrogen: The most powerful rocket fuel yet to exist

Energy Technology Data Exchange (ETDEWEB)

Silvera, Isaac F [Lyman Laboratory of Physics, Harvard University, Cambridge MA 02138 (United States); Cole, John W, E-mail: silvera@physics.harvard.ed [NASA MSFC, Huntsville, AL 35801 (United States)

2010-03-01

Wigner and Huntington first predicted that pressures of order 25 GPa were required for the transition of solid molecular hydrogen to the atomic metallic phase. Later it was predicted that metallic hydrogen might be a metastable material so that it remains metallic when pressure is released. Experimental pressures achieved on hydrogen have been more than an order of magnitude higher than the predicted transition pressure and yet it remains an insulator. We discuss the applications of metastable metallic hydrogen to rocketry. Metastable metallic hydrogen would be a very light-weight, low volume, powerful rocket propellant. One of the characteristics of a propellant is its specific impulse, I{sub sp}. Liquid (molecular) hydrogen-oxygen used in modern rockets has an Isp of {approx}460s; metallic hydrogen has a theoretical I{sub sp} of 1700s. Detailed analysis shows that such a fuel would allow single-stage rockets to enter into orbit or carry economical payloads to the moon. If pure metallic hydrogen is used as a propellant, the reaction chamber temperature is calculated to be greater than 6000 K, too high for currently known rocket engine materials. By diluting metallic hydrogen with liquid hydrogen or water, the reaction temperature can be reduced, yet there is still a significant performance improvement for the diluted mixture.

Hydrogen behaviour and mitigation in water-cooled nuclear power reactors

International Nuclear Information System (INIS)

Della Loggia, E.

1992-01-01

The Commission of the European Communities (CEC) and the International Atomic Energy Agency (IAEA), within the framework of their safety research activities, initiated and arranged a series of specialist meetings and research contracts on hydrogen behaviour and control. The result of this work is summarized in a report jointly prepared by the two international organizations entitled 'Hydrogen in water-cooled nuclear power reactors'. Independently, the Kurchatov Atomic Energy Institute organized a workshop on the hydrogen issue in Sukhumi, USSR, with CEC and IAEA cooperation. Commonly expressed views have emerged and recommendations were formulated to organize the subsequent seminar/workshop concentrating mainly on the most recent research and analytical projects and findings related to the hydrogen behaviour, and-most importantly-on the practical approaches and engineering solutions to the hydrogen control and mitigation. The seminar/workshop, therefore, addressed the 'theory and practice' aspects of the hydrogen issue. The workshop was structured in the following sessions: combustible gas production; hydrogen distribution; combustion phenomena; combustion effects and threats; and detection and migration

Autonomous Operation of Super-Regenerative Receiver in BAN

NARCIS (Netherlands)

Kalyanasundaram, P.; Huang, L.; Dolmans, G.; Imamura, K.

2012-01-01

Super-regenerative receiver is one of the potential candidates to achieve ultra low power wireless communication in body area network (BAN). The main limitations of the super-regenerative receiver include the difficulty in choosing a good quench waveform to optimize its sensitivity and selectivity,

Sulfide stress corrosion study of a super martensitic stainless steel in H2S sour environments: Metallic sulfides formation and hydrogen embrittlement

Science.gov (United States)

Monnot, Martin; Nogueira, Ricardo P.; Roche, Virginie; Berthomé, Grégory; Chauveau, Eric; Estevez, Rafael; Mantel, Marc

2017-02-01

Thanks to their high corrosion resistance, super martensitic stainless steels are commonly used in the oil and gas industry, particularly in sour environments. Some grades are however susceptible to undergo hydrogen and mechanically-assisted corrosion processes in the presence of H2S, depending on the pH. The martensitic stainless steel EN 1.4418 grade exhibits a clear protective passive behavior with no sulfide stress corrosion cracking when exposed to sour environments of pH ≥ 4, but undergoes a steep decrease in its corrosion resistance at lower pH conditions. The present paper investigated this abrupt loss of corrosion resistance with electrochemical measurements as well as different physicochemical characterization techniques. Results indicated that below pH 4.0 the metal surface is covered by a thick (ca 40 μm) porous and defect-full sulfide-rich corrosion products layer shown to be straightforwardly related to the onset of hydrogen and sulfide mechanically-assisted corrosion phenomena.

Complete super-sample lensing covariance in the response approach

Science.gov (United States)

Barreira, Alexandre; Krause, Elisabeth; Schmidt, Fabian

2018-06-01

We derive the complete super-sample covariance (SSC) of the matter and weak lensing convergence power spectra using the power spectrum response formalism to accurately describe the coupling of super- to sub-survey modes. The SSC term is completely characterized by the survey window function, the nonlinear matter power spectrum and the full first-order nonlinear power spectrum response function, which describes the response to super-survey density and tidal field perturbations. Generalized separate universe simulations can efficiently measure these responses in the nonlinear regime of structure formation, which is necessary for lensing applications. We derive the lensing SSC formulae for two cases: one under the Limber and flat-sky approximations, and a more general one that goes beyond the Limber approximation in the super-survey mode and is valid for curved sky applications. Quantitatively, we find that for sky fractions fsky ≈ 0.3 and a single source redshift at zS=1, the use of the flat-sky and Limber approximation underestimates the total SSC contribution by ≈ 10%. The contribution from super-survey tidal fields to the lensing SSC, which has not been included in cosmological analyses so far, is shown to represent about 5% of the total lensing covariance on multipoles l1,l2 gtrsim 300. The SSC is the dominant off-diagonal contribution to the total lensing covariance, making it appropriate to include these tidal terms and beyond flat-sky/Limber corrections in cosmic shear analyses.

Water leak detection in steam generator of Super Phenix

International Nuclear Information System (INIS)

Kong, N.; Brunet, M.; Garnaud, P.; Ghaleb, D.

1990-01-01

With the intent of detecting water leaks inside steam generators, we developed a third system, called acoustic detector, to complement hydrogen detectors and rupture disks (burst disks). The role of the acoustic system is to enable rapid intervention in the event of a leak growing rapidly which could rupture neighbouring tubes. In such a case, the detectable flow rate of the leak varies from a few tens of g/s to a few hundred g/s. At the Super Phenix, three teams work in parallel in complementary frequency bands: EDF (0-20 kHz), CEA/SPCI (20-100 kHz) and CEA/STA (50-300 kHz). The simulation of water leaks in the steam generator by the argon injections performed to date at 50% of the rated power has shown promising results. An anomaly in the evolution of the background noise at more than 50% loading of one of the two instrumented steam generators would make difficult any extrapolation to full power behaviour. 5 refs, 6 figs, 1 tab

Effect of using hydrogen in the power and performance of an internal combustion engine

Directory of Open Access Journals (Sweden)

Edwin Tamayo

2016-12-01

Full Text Available This study analyzed the real working parameters of an Otto cycle internal combustion engine, using as fuel hydrogen plus gasoline. Two stoichiometric equations were determined. In the first equation, the reagents are octane and air, in the second equation was added the quantity of 3.86 H2 moles obtained from a hydrogen cell. Two sets of equations, for consumption and power, were determined from the chemical equations, working at the conditions of Quito: altitude 2850 msnm, 72.794 kPa of atmospheric pressure and 300 K of temperature. A single cylinder engine powered with hydrogen plus gasoline was used for getting real data of engine power, using mixtures of air-gasoline and hydrogen; the theoretical power without H2 was 3.91 HP and with H2 5.41 HP, it increased 27.1%, the real power is 3.78 HP without H2 and 4.66 HP with H2, it increased 16.7%. Theoretical fuel consumption is 401.61 g/kWh and addition of H2 is less to 373.52 g/kWh, the actual consumption that indicates the manufacturer is 395 g/kWh.

Two-reduction of the super-KP hierarchy

International Nuclear Information System (INIS)

McArthur, I.N.

1994-01-01

Recursion relations are established for the residues of fractional powers of a two-reduced super-KP operator making use of the Baker-Akhiezer function. These show the integrability of the two-reduced even (or bosonic) flows of the super-KP hierarchy. Similar recursion relations are also proven for the residues of operators associated with the odd (or fermionic) flows of the Mulase-Rabin super-KP hierarchy. Due to the presence of a spectral parameter and itts fermionic partner in the Baker-Akhiezer function, these recursion relations should be relevant to any attempt to prove or disprove a recent proposal that the integrable hierarchy underlying two-dimensional quantum supergravity is the Mulase-Rabin super-KP hierarchy. (orig.)

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

Hydrogen-oxygen steam generator applications for increasing the efficiency, maneuverability and reliability of power production

Science.gov (United States)

Schastlivtsev, A. I.; Borzenko, V. I.

2017-11-01

The comparative feasibility study of the energy storage technologies showed good applicability of hydrogen-oxygen steam generators (HOSG) based energy storage systems with large-scale hydrogen production. The developed scheme solutions for the use of HOSGs for thermal power (TPP) and nuclear power plants (NPP), and the feasibility analysis that have been carried out have shown that their use makes it possible to increase the maneuverability of steam turbines and provide backup power supply in the event of failure of the main steam generating equipment. The main design solutions for the integration of hydrogen-oxygen steam generators into the main power equipment of TPPs and NPPs, as well as their optimal operation modes, are considered.

Study of a molten carbonate fuel cell combined heat, hydrogen and power system: Energy analysis

International Nuclear Information System (INIS)

Agll, Abdulhakim Amer A.; Hamad, Yousif M.; Hamad, Tarek A.; Thomas, Mathew; Bapat, Sushrut; Martin, Kevin B.; Sheffield, John W.

2013-01-01

Countries around the world are trying to use alternative fuels and renewable energy to reduce the energy consumption and greenhouse gas emissions. Biogas contains methane is considered a potential source of clean renewable energy. This paper discusses the design of a combined heat, hydrogen and power system, which generated by methane with use of Fuelcell, for the campus of Missouri University of Science and Technology located in Rolla, Missouri, USA. An energy flow and resource availability study was performed to identify sustainable type and source of feedstock needed to run the Fuelcell at its maximum capacity. FuelCell Energy's DFC1500 unit (a molten carbonate Fuelcell) was selected as the Fuelcell for the tri-generation (heat, hydrogen and electric power) system. This tri-generation system provides electric power to the campus, thermal energy for heating the anaerobic digester, and hydrogen for transportation, backup power and other applications on the campus. In conclusion, the combined heat, hydrogen and power system reduces fossil fuel usage, and greenhouse gas emissions at the university campus. -- Highlights: • Combined heat, hydrogen and power (CHHP) using a molten carbonate fuel cell. • Energy saving and alternative fuel of the products are determined. • Energy saving is increased when CHHP technology is implemented. • CHHP system reduces the greenhouse gas emissions and fuel consumption

Design of arc power supply for neutral beam injection system based on super capacitor energy storage

International Nuclear Information System (INIS)

Yang Puqiong; Xuan Weimin; Cao Jianyong; Li Qing; Liu Xiaolong

2015-01-01

The arc power supply is one of the most important equipment for neutral beam injection system. The stability of arc discharge and the quality of ion beam extraction were determined by its performance. For improving stability of the arc discharge, reducing the power network capacity and decreasing impulse on power network, the topology of the arc power supply applied the structure of DC/DC converter based on technology of super capacitor energy storage and switching power supply. Several IGBT power modules are operated in parallel, and it can improve the arc power supply's operating frequency and dynamic response. A filter circuit and a current fast transferring circuit were designed based on a detailed analysis on working process of the arc power sup- ply. According to the requirements and parameters of the arc power supply, and the current response of RL first order circuit, the minimum filter inductances were accurately calculated. Finally, using the model and Matlab, the performance of the arc power supply was simulated and verified, and it meets the design requirement. (authors)

Safety Implementation of Hydrogen Igniters and Recombiners for Nuclear Power Plant Severe Accident Management

Institute of Scientific and Technical Information of China (English)

XIAO Jianjun; ZHOU Zhiwei; JING Xingqing

2006-01-01

Hydrogen combustion in a nuclear power plant containment building may threaten the integrity of the containment. Hydrogen recombiners and igniters are two methods to reduce hydrogen levels in containment buildings during severe accidents. The purpose of this paper is to evaluate the safety implementation of hydrogen igniters and recombiners. This paper analyzes the risk of deliberate hydrogen ignition and investigates three mitigation measures using igniters only, hydrogen recombiners only or a combination of recombiners and igniters. The results indicate that steam can effectively control the hydrogen flame acceleration and the deflagration-to-detonation transition.

Design and analysis on super-critical water cooled power reactors

International Nuclear Information System (INIS)

Ishiwatari, Yuki

2005-01-01

The Super-Critical Water Cooled Power Reactors (SCPR) is cooled by 25 MPa supercritical water of 280degC at reactor inlet and greater than 500degC at reactor outlet and directly connected with turbine/generators with high energy conversion efficiency. This corresponds to the deletion of recirculation system and steam-water separation system of BWR type reactors or of pressurizer and steam generator of PWR type reactors. In addition to the design study of the university of Tokyo, technology development of the SCPR for practical use has started under the collaboration of industry and academia since 2000. Mockup single tube and bundle tests for heat transfer/fluid flow characteristics of the design have been conducted with 3D heat transfer analysis. Materials compatible with coolant conditions for fuel cans and reactor internals are also assessed. Overall evaluation of the reactor concept is under way. (T. Tanaka)

Steam generator development in France for the Super Phenix project; Generateurs de vapeur developpes en France pour Super Phenix

Energy Technology Data Exchange (ETDEWEB)

Robin, M G

1975-07-01

'Steam Generator Development for Super Phenix Project'. The development program of steam generators studied by Fives-Cail Babcock and Stein Industrie Companies, jointly with CEA end EDF, for the Super Phenix 1200 MWe Fast Breeder Power Plant, is presented. The main characteristics of both sodium heated steam generators are emphasized and experimental studies related to their key features are reported. (author)

Impact of Storage Technologies upon Power System Losses

Directory of Open Access Journals (Sweden)

DULAU Lucian Ioan

2015-05-01

Full Text Available The paper describes the main characteristics of storage technologies. The most important storage technologies are the batteries, hydrogen, pumped hydro, flywheels, compressed air, super-capacitors and superconducting magnetic devices. The storage technologies can be classified based on the function principle into electrochemical, mechanical and electromagnetic devices. The storage systems can also be classified based on their capacity to store power into short and long term devices. A power flow analysis is performed for the situation with and without a storage unit. The storage unit is inserted into the IEEE 14 bus test system.

Autonomous hydrogen power plants with renewable energy sources

International Nuclear Information System (INIS)

Popel', O.S.; Frid, S.E.; Shpil'rajn, Eh.Eh.; Izosimov, D.B.; Tumanov, V.L.

2006-01-01

One studies the principles to design independent hydrogen power plants (IHPP) operating on renewable energy sources and the approaches to design a pilot IHP plant. One worded tasks of mathematical simulation and of calculations to substantiate the optimal configuration of the mentioned plants depending on the ambient conditions of operation and on peculiar features of a consumer [ru

Reference Concepts for a Space-Based Hydrogen-Oxygen Combustion, Turboalternator, Burst Power System

National Research Council Canada - National Science Library

Edenburn, Michael

1990-01-01

This report describes reference concepts for a hydrogen-oxygen combustion, turboalternator power system that supplies power during battle engagement to a space-based, ballistic missile defense platform...

Influence of moisture and hydrogen purity of the reliability of powerful electric machines

International Nuclear Information System (INIS)

Vigovs'kij, O.V.; Khvalyin, D.Yi.; Mistets'kij, V.A.

2017-01-01

It is shown that today the turbo generators with hydrogen-water cooling system is most unreliable technical equipment of Ukrainian nuclear power plants. On the one hand, hydrogen has several advantages over other coolers; on the other hand, the presence of hydrogen in the turbo generators systems carries the danger of engine rooms of power plants. It is also shown that the water and oxygen are main hazardous impurities in hydrogen, and zone of generator shaft compaction is the most responsible zone with high concentration of water. From the analysis was found that increasing of hydrogen purity reduces the mechanical losses and the change in total losses depending on the hydrogen purity has a linear nature. For example, with an increase the hydrogen purity from 0,1203 to 0,09 the loss in turbo generator rotor can be reduced by nearly 500 kW, which is about 25 % at a pressure of 0,5 MPa. The possibility of using metal hydrides to ensure purity, purification and hydrogen sorption was looked. The most practical value is for such hydrides as LaNi5Hx, FeTiHx, ZrNiHx. The main advantage the metal hydrides method of purification is a significant reduction in the number of purification stages. It was shown that the use of a thermoelectric gas dryer will reduce the total consumption of technological gases, that are removed from nuclear power plants, by 2,3 - 2,4 times due to a decrease in 5,0 - 6,0 times their absolute humidity, and decrease by 5, 0 times the activity of gases due to an increase in their exposure time in the decrease activity installation. All this suggests that the creation a hydrogen humidity monitoring system in the exploited turbo generator will solve the problem of objective control of hydrogen purity with further computerization and accumulation the information. Using a drainage or purification system of hydrogen, reducing the temperature and humidity of the cooling gas, can increase the reliability of operation the turbo generators and significantly

Teaching - methodical and research center of hydrogen power engineering and platinum group metals in the former Soviet Union countries

International Nuclear Information System (INIS)

Evdokimov, A.A; Sigov, A.S; Shinkarenko, V.V.

2005-01-01

Full text: Teaching - Methodical and Research Center (TMRC) 'Sokolinaja Gora' is founded in order to provide methodical-information and scientific support of institutes of higher education in the field of hydrogen power engineering and platinum group metals in Russia and in the countries of the Former Soviet union. It is independent association of creative communities of scientist of higher educational specialists. The main directions of the Center activity are: 1. Teaching-methodological support and development of teaching in the field of hydrogen power engineering and platinum group metals in Russia in the countries of the Former Soviet Union. Themes of teaching includes the basic of safe using of hydrogen technologies and devices, ecological, economic and law aspects of new hydrogen power engineering, transition to which in 21 century is one of the central problems of mankind survival; 2. Organizing of joint researches by independent creative communities of scientists in the field of hydrogen power engineering and platinum group metal; 3. Independent scientific examination, which is made by Advisory Committee of High Technologies consisting of representatives of the countries of Former Soviet Union, which are standing participants of an Annual International Symposia 'Hydrogen Power Engineering and Platinum Group Metals in the Former Soviet Union Countries'. Structure of the Center: 1. Center of strategic development in the field of high technologies; 2. Scientific Research Institute of Hydrogen Power Engineering and Platinum Group Metals; 3. Teaching-Methodical Association in specialization 'Hydrogen Power Engineering and economics' and hydrogen wide spread training; 4. Media Center 'Hydrogen Power Engineering and Platinum Group Metals', 5. Organizational Center; 6. Administrative Center. The Center will be established step-by-step in 2005-2010 on the basis of the following programs: Teaching-methodological program. On the basis of this program it is planned to

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

International Nuclear Information System (INIS)

Chintawar, P.S.; Block, G.

2004-01-01

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

Contribution to dimensioning a pack of super-capacitors for 12/42 V application

Energy Technology Data Exchange (ETDEWEB)

Rafik, F.; Karmous, M. [Ecole d' Ingenieurs de l' Arc Jurassien, CH (Switzerland); Gualous, H.; Berthon, A. [Universite de Franche-Comte, Lab. en Electronique, Electrotechnique et Systemes (L2ES), UTBM, 90 - Belfort (France); Gallay, R. [Maxwell Technologies, CH (Switzerland)

2004-07-01

Increase power demands on automotive are making current 12/14 V electrical systems inadequate. The total power demand will triple in some cars from 800 W today to an average of 2500 W and into kW range for peak demand in the future. Super-capacitor can be used for energy storage and for peak power requirement in order to increase the efficiency and the life cycle of the system. However, the sizing of energy storage with super-capacitors is very important for embedded applications, because of the weight and the volume of the system. This paper presents a sizing method of a pack of super-capacitors. The proposed method is based on the power and energy demand. In order to validate this method, a model of the Maxwell cell BCAP0010 of super-capacitors is presented and implemented in the SIMPLORER software. (authors)

Hydrogen transfer preventive device in FBR power plant

International Nuclear Information System (INIS)

Hoshi, Yuichi.

1987-01-01

Purpose: To prevent transfer of hydrogen, etc. in FBR power plant. Constitution: Since H 2 permeates heat conduction pipes in a steam generator, it is necessary to eliminate all of permeation hydrogen, etc. by primary cold traps particularly in the case of saving the intermediate heat exchange. In view of the above, the heat conduction pipes of the steam generator are constituted as a double pipe structure and helium gases are recycled through the gaps thereof and hydrogen traps are disposed to the recycling path. H 2 released into water flowing through the inside of the inner pipe is permeated through the inner pipe and leached into the gap, but the leached H 2 is carried by the helium recycling stream to the hydrogen trap and then the H 2 stream removed with H 2 is returned to the gaps. In this way, the capacity of the primary cold traps disposed in the liquid sodium recycling circuit can be reduced remarkably and the capacity of the purifying device, if an intermediate heat exchanger is disposed, is also reduced to decrease the plant cost. Further, diffusion of deleterious gases from the primary to the secondary circuits can be prevented as well. (Kamimura, M.)

Hydrogen-powered road vehicles. Positive and negative health effects of new fuel

International Nuclear Information System (INIS)

2008-09-01

Because of the political, social and environmental problems associated with dependency on fossil fuels, there is considerable interest in alternative energy sources. Hydrogen is regarded as a promising option, particularly as a fuel for road vehicles. The Dutch Energy research Centre of the Netherlands (ECN) recently published a vision of the future, in which it suggested that by 2050 more than half of all cars in the Netherlands could be running on hydrogen. Assuming that the hydrogen is produced from renewable energy sources, migration to hydrogen-powered vehicles would also curb carbon dioxide emissions. In the United States, Japan and Europe, considerable public and private investment is therefore being made with a view to developing the technologies needed to make the creation of a hydrogen-based economy possible within a few decades. A switch to using hydrogen as the primary energy source for road vehicles would have far-reaching social consequences. As with all technological developments, opportunities would be created, but drawbacks would inevitably be encountered as well. Some of the disadvantages associated with hydrogen are already known, and are to some degree manageable. It is likely, however, that other drawbacks would come to light only once hydrogen-powered cars were actually in use With that thought in mind, and in view of the social significance of a possible transition to hydrogen, it was decided that the Health Council should assess the positive and negative effects that hydrogen use could have on public health. It is particularly important to make such an assessment at the present early stage in the development of hydrogen technologies, so that gaps in existing scientific knowledge may be identified and appropriate strategies may be developed for addressing such gaps. This report has been produced by the Health and Environment Surveillance Committee, which has special responsibility for the identification of important correlations between

Super-low-frequency wireless power transfer with lightweight coils for passing through a stainless steel plate

Science.gov (United States)

Ishida, Hiroki; Kyoden, Tomoaki; Furukawa, Hiroto

2018-03-01

To achieve wireless power transfer (WPT) through a stainless-steel plate, a super-low frequency (SLF) was used as a resonance frequency. In our previous study of SLF-WPT, heavy coils were prepared. In this study, we designed lightweight coils using a WPT simulator that we developed previously. As a result, the weight was reduced to 1.69 kg from 11.9 kg, the previous coil weight. At a resonance frequency of 400 Hz, the transmission efficiency and output power of advanced SLF-WPT reached 91% and 426 W, respectively, over a transmission distance of 30 mm. Furthermore, 80% efficiency and 317 W output were achieved when transmitting power through a 1 mm-thick stainless-steel plate. This performance is much better than that in previous reports. We show using both calculations and experimental results that a power-to-weight ratio of 252 W/kg is possible even when using a 400 Hz power supply frequency.

Hydrogen co-production from subcritical water-cooled nuclear power plants in Canada

Energy Technology Data Exchange (ETDEWEB)

Gnanapragasam, N.; Ryland, D.; Suppiah, S., E-mail: gnanapragasamn@aecl.ca [Atomic Energy of Canada Limited, Chalk River, Ontario (Canada)

2013-06-15

Subcritical water-cooled nuclear reactors (Sub-WCR) operate in several countries including Canada providing electricity to the civilian population. The high-temperature-steam-electrolysis process (HTSEP) is a feasible and laboratory-demonstrated large-scale hydrogen-production process. The thermal and electrical integration of the HTSEP with Sub-WCR-based nuclear-power plants (NPPs) is compared for best integration point, HTSEP operating condition and hydrogen production rate based on thermal energy efficiency. Analysis on integrated thermal efficiency suggests that the Sub-WCR NPP is ideal for hydrogen co-production with a combined efficiency of 36%. HTSEP operation analysis suggests that higher product hydrogen pressure reduces hydrogen and integrated efficiencies. The best integration point for the HTSEP with Sub-WCR NPP is upstream of the high-pressure turbine. (author)

Failure investigation of super heater tubes of coal fired power plant

Directory of Open Access Journals (Sweden)

A.K. Pramanick

2017-10-01

Full Text Available Cause of failure of two adjacent super heater tubes made of Cr-Mo steel of a coal based 60 MW thermal power plant has been portrayed in present investigation. Oxide deposits were found on internal surface of tubes. Deposits created significant resistance to heat transfer and resulted in undesirable rise in component temperature. This situation, in turn, aggravated the condition of gas side that was exposed to high temperature. Localized heating coarsened carbides as well as propelled precipitation of new brittle phases along grain boundary resulting in embrittlement of tube material. Continuous exposure to high temperature softened the tube material and tube wall was thinned down with bulging toward outside. Creep void formation along grain boundary was observed and steered intergranular cracking. All these effects contributed synergistically and tubes were failed ultimately due to overload under high Hoop stress.

Hydrogen Village : creating hydrogen and fuel cell communities

International Nuclear Information System (INIS)

Smith, G.R.

2009-01-01

The Hydrogen Village (H2V) is a collaborative public-private partnership administered through Hydrogen and Fuel Cells Canada and funded by the Governments of Canada and Ontario. This end user-driven, market development program accelerates the commercialization of hydrogen and fuel cell (FC) technologies throughout the Greater Toronto Area (GTA). The program targets 3 specific aspects of market development, notably deployment of near market technologies in community based stationary and mobile applications; development of a coordinated hydrogen delivery and equipment service infrastructure; and societal factors involving corporate policy and public education. This presentation focused on lessons learned through outreach programs and the deployment of solid oxide fuel cell (SOFC) heat and power generation; indoor and outdoor fuel cell back up power systems; fuel cell-powered forklifts, delivery vehicles, and utility vehicles; hydrogen internal combustion engine powered shuttle buses, sedans, parade float; hydrogen production/refueling stations in the downtown core; and temporary fuel cell power systems

Super-quantum curves from super-eigenvalue models

Energy Technology Data Exchange (ETDEWEB)

Ciosmak, Paweł [Faculty of Mathematics, Informatics and Mechanics, University of Warsaw,ul. Banacha 2, 02-097 Warsaw (Poland); Hadasz, Leszek [M. Smoluchowski Institute of Physics, Jagiellonian University,ul. Łojasiewicza 11, 30-348 Kraków (Poland); Manabe, Masahide [Faculty of Physics, University of Warsaw,ul. Pasteura 5, 02-093 Warsaw (Poland); Sułkowski, Piotr [Faculty of Physics, University of Warsaw,ul. Pasteura 5, 02-093 Warsaw (Poland); Walter Burke Institute for Theoretical Physics, California Institute of Technology,1200 E. California Blvd, Pasadena, CA 91125 (United States)

2016-10-10

In modern mathematical and theoretical physics various generalizations, in particular supersymmetric or quantum, of Riemann surfaces and complex algebraic curves play a prominent role. We show that such supersymmetric and quantum generalizations can be combined together, and construct supersymmetric quantum curves, or super-quantum curves for short. Our analysis is conducted in the formalism of super-eigenvalue models: we introduce β-deformed version of those models, and derive differential equations for associated α/β-deformed super-matrix integrals. We show that for a given model there exists an infinite number of such differential equations, which we identify as super-quantum curves, and which are in one-to-one correspondence with, and have the structure of, super-Virasoro singular vectors. We discuss potential applications of super-quantum curves and prospects of other generalizations.

Super-quantum curves from super-eigenvalue models

International Nuclear Information System (INIS)

Ciosmak, Paweł; Hadasz, Leszek; Manabe, Masahide; Sułkowski, Piotr

2016-01-01

In modern mathematical and theoretical physics various generalizations, in particular supersymmetric or quantum, of Riemann surfaces and complex algebraic curves play a prominent role. We show that such supersymmetric and quantum generalizations can be combined together, and construct supersymmetric quantum curves, or super-quantum curves for short. Our analysis is conducted in the formalism of super-eigenvalue models: we introduce β-deformed version of those models, and derive differential equations for associated α/β-deformed super-matrix integrals. We show that for a given model there exists an infinite number of such differential equations, which we identify as super-quantum curves, and which are in one-to-one correspondence with, and have the structure of, super-Virasoro singular vectors. We discuss potential applications of super-quantum curves and prospects of other generalizations.

Super-quantum curves from super-eigenvalue models

Science.gov (United States)

Ciosmak, Paweł; Hadasz, Leszek; Manabe, Masahide; Sułkowski, Piotr

2016-10-01

In modern mathematical and theoretical physics various generalizations, in particular supersymmetric or quantum, of Riemann surfaces and complex algebraic curves play a prominent role. We show that such supersymmetric and quantum generalizations can be combined together, and construct supersymmetric quantum curves, or super-quantum curves for short. Our analysis is conducted in the formalism of super-eigenvalue models: we introduce β-deformed version of those models, and derive differential equations for associated α/ β-deformed super-matrix integrals. We show that for a given model there exists an infinite number of such differential equations, which we identify as super-quantum curves, and which are in one-to-one correspondence with, and have the structure of, super-Virasoro singular vectors. We discuss potential applications of super-quantum curves and prospects of other generalizations.

Hydrogen and nuclear power

International Nuclear Information System (INIS)

Holt, D.J.

1976-12-01

This study examines the influence that the market demand for hydrogen might have on the development of world nuclear capacity over the next few decades. In a nuclear economy, hydrogen appears to be the preferred energy carrier over electricity for most purposes, due to its ready substitution and usage for all energy needs, as well as its low transmission costs. The economic factors upon which any transition to hydrogen fuelling will be largely based are seen to be strongly dependent on the form of future energy demand, the energy resource base, and on the status of technology. Accordingly, the world energy economy is examined to identify the factors which might affect the future demand price structure for energy, and a survey of current estimates of world energy resources, particularly oil, gas, nuclear, and solar, is presented. Current and projected technologies for production and utilization of hydrogen are reviewed, together with rudimentary cost estimates. The relative economics are seen to favour production of hydrogen from fossil fuels far into the foreseeable future, and a clear case emerges for high temperature nuclear reactors in such process heat applications. An expanding industrial market for hydrogen, and near term uses in steelmaking and aircraft fuelling are foreseen, which would justify an important development effort towards nuclear penetration of that market. (author)

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.

Recent advances in Reltron and Super-Reltron HPM source development

Science.gov (United States)

Miller, Robert B.; Muehlenweg, Carl A.; Habiger, Kerry W.; Smith, John R.; Shiffler, Donald A.

1994-05-01

Reltron and super-reltron microwave tubes use post acceleration of a well-modulated beam and multiple output cavity extraction sections to generate high power microwave pulses with excellent efficiency. We have continued our development of these tubes with emphasis being given to four specific topics: (1) Recent experiments with our 1-GHz super-reltron tube have demonstrated operation at a peak power level of 600 MW. With pulse durations of several hundred nanoseconds, the microwave energy per pulse is about 250 J. (2) We have extracted significant power (several tens of megawatts) at the third multiple (3 GHz) of our 1-GHz super-reltron tube using output cavities designed for operation in S-band. (3) We have fielded a small S-band super-reltron tube on our 260 kV modulator. We have obtained lifetime data for this tube under repetitive (20 Hz), long pulse (2 microsecond(s) ec) operating conditions. (4) We have initiated feasibility experiments of the reltron concept by post accelerating the bunched beam produced by a SLAC XK-5 klystron. In this paper we report our experimental results and discuss relevant theoretical considerations related to each of these four topics.

Super-iron Nanoparticles with Facile Cathodic Charge Transfer

Energy Technology Data Exchange (ETDEWEB)

M Farmand; D Jiang; B Wang; S Ghosh; D Ramaker; S Licht

2011-12-31

Super-irons contain the + 6 valence state of iron. One advantage of this is that it provides a multiple electron opportunity to store additional battery charge. A decrease of particle size from the micrometer to the nanometer domain provides a higher surface area to volume ratio, and opportunity to facilitate charge transfer, and improve the power, voltage and depth of discharge of cathodes made from such salts. However, super-iron salts are fragile, readily reduced to the ferric state, with both heat and contact with water, and little is known of the resultant passivating and non-passivating ferric oxide products. A pathway to decrease the super-iron particle size to the nano-domain is introduced, which overcomes this fragility, and retains the battery capacity advantage of their Fe(VI) valence state. Time and power controlled mechanosynthesis, through less aggressive, dry ball milling, leads to facile charge transfer of super-iron nanoparticles. Ex-situ X-ray Absorption Spectroscopy is used to explore the oxidation state and structure of these iron oxides during discharge and shows the significant change in stability of the ferrate structure to lower oxidation state when the particle size is in the nano-domain.

Alkaline sodium borohydride gel as a hydrogen source for PEMFC or an energy carrier for NaBH 4-air battery

Science.gov (United States)

Liu, B. H.; Li, Z. P.; Chen, L. L.

In this preliminary study, we tried to use sodium polyacrylate as the super absorbent polymer to form alkaline NaBH 4 gel and explored its possibilities for borohydride hydrolysis and borohydride electro-oxidation. It was found that the absorption capacity of sodium polyacrylate decreased with increasing NaBH 4 concentration. The formed gel was rather stable in the sealed vessel but tended to slowly decompose in open air. Hydrogen generation from the gel was carried out using CoCl 2 catalyst precursor solutions. Hydrogen generation rate from the alkaline NaBH 4 gel was found to be higher and impurities in hydrogen were less than that from the alkaline NaBH 4 solution. The NaBH 4 gel also successfully powered a NaBH 4-air battery.

Getting super-excited with modified dispersion relations

Energy Technology Data Exchange (ETDEWEB)

Ashoorioon, Amjad; Casadio, Roberto [INFN—Sezione di Bologna, viale B. Pichat 6/2, I-40127 Bologna (Italy); Geshnizjani, Ghazal; Kim, Hyung J., E-mail: amjad.ashoorioon@bo.infn.it, E-mail: roberto.casadio@bo.infn.it, E-mail: ggeshniz@uwaterloo.ca, E-mail: h268kim@uwaterloo.ca [Department of Applied Mathematics, University of Waterloo Waterloo, Ontario, N2L 3G1 (Canada)

2017-09-01

We demonstrate that in some regions of parameter space, modified dispersion relations can lead to highly populated excited states, which we dub as 'super-excited' states. In order to prepare such super-excited states, we invoke dispersion relations that have negative slope in an interim sub-horizon phase at high momenta. This behaviour of quantum fluctuations can lead to large corrections relative to the Bunch-Davies power spectrum, which mimics highly excited initial conditions. We identify the Bogolyubov coefficients that can yield these power spectra. In the course of this computation, we also point out the shortcomings of the gluing method for evaluating the power spectrum and the Bogolyubov coefficients. As we discuss, there are other regions of parameter space, where the power spectrum does not get modified. Therefore, modified dispersion relations can also lead to so-called 'calm excited states'. We conclude by commenting on the possibility of obtaining these modified dispersion relations within the Effective Field Theory of Inflation.

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

Study of the pulse power supply unit for the four-horn system of the CERN to Fréjus neutrino super beam

CERN Document Server

Baussan, E; Dracos, M; Gaudiot, G; Osswald, F; Poussot, P; Vassilopoulos, N; Wurtz, J; Zeter, V

2013-01-01

The power supply studies for the four-horn system for the CERN to Fréjus neutrino Super Beam oscillation experiment are discussed here. The power supply is being studied to meet the physics potential and the mega-watt (MW) power requirements of the proton driver of the Super Beam. A one-half sinusoid current waveform with a 350 kA maximum current and pulse length of 100 \\mu s at 50 Hz frequency is generated and distributed to four-horns. In order to provide the necessary current needed to focus the charged mesons producing the neutrino beam, a bench of capacitors is charged at 50 Hz frequency to a +12 kV reference voltage and then discharged through a large switch to each horn via a set of strip-lines at the same rate. A current recovery stage allows to invert rapidly the negative voltage of the capacitor after the discharging stage in order to recuperate large part of the injected energy and thus to limit the power consuption. The energy recovery efficiency of that system is very high at 97%. For feasibilit...

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

Science.gov (United States)

2017-12-01

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

COMPARATIVE ANALYSIS OF ENERGY ACCUMULATION SYSTEMS AND DETERMINATION OF OPTIMAL APPLICATION AREAS FOR MODERN SUPER FLYWHEELS

Directory of Open Access Journals (Sweden)

M. A. Sokolov

2014-07-01

Full Text Available The paper presents a review and comparative analysis of late years native and foreign literature on various energy storage devices: state of the art designs, application experience in various technical fields. Comparative characteristics of energy storage devices are formulated: efficiency, quality and stability. Typical characteristics are shown for such devices as electrochemical batteries, super capacitors, pumped hydroelectric storage, power systems based on compressed air and superconducting magnetic energy storage systems. The advantages and prospects of high-speed super flywheels as means of energy accumulation in the form of rotational kinetic energy are shown. High output power of a super flywheels energy storage system gives the possibility to use it as a buffer source of peak power. It is shown that super flywheels have great life cycle (over 20 years and are environmental. A distinctive feature of these energy storage devices is their good scalability. It is demonstrated that super flywheels are especially effective in hybrid power systems that operate in a charge/discharge mode, and are used particularly in electric vehicles. The most important factors for space applications of the super flywheels are their modularity, high efficiency, no mechanical friction and long operating time without maintenance. Quick response to network disturbances and high power output can be used to maintain the desired power quality and overall network stability along with fulfilling energy accumulation needs.

SuperB Bunch-By-Bunch Feedback R&D

Energy Technology Data Exchange (ETDEWEB)

Drago, A.; Beretta, M.; /Frascati; Bertsche, K.; Novokhatski, A.; /SLAC; Migliorati, M.; /Rome U.

2011-08-12

The SuperB project has the goal to build in Italy, in the Frascati or Tor Vergata area, an asymmetric e{sup +}/e{sup -} Super Flavor Factory to achieve a peak luminosity > 10**36 cm{sup -2} s{sup -1}. The SuperB design is based on collisions with extremely low vertical emittance beams and high beam currents. A source of emittance growth comes from the bunch by bunch feedback systems producing high power correction signals to damp the beams. To limit any undesirable effect, a large R&D program is in progress, partially funded by the INFN Fifth National Scientific Committee through the SFEED (SuperB Feedback) project approved within the 2010 budget. The SuperB project [1] has the goal to build in Italy, in the Frascati or Tor Vergata area, an asymmetric e{sup +}/e{sup -} Super Flavor Factory to achieve a peak luminosity > 10**36 cm{sup -2} s{sup -1}. In the last and current years, the machine layout has been deeply modified, in particular the main rings are now shorter and an option with high currents has been foreseen. In the fig.1 the new SuperB layout is shown. From bunch-by-bunch feedback point of view, the simultaneous presence in the machine parameters, of very low emittance, of the order of 5-10 pm in the vertical plane, and very high currents, at level of 4 Ampere for the Low Energy Ring, asks for designing very carefully the bunch-by-bunch feedback systems. The parameter list is presented in Fig. 2. The bunch-by-bunch feedback design must take care of the risky and exciting challenges proposed in the SuperB specifications, but it should consider also some other important aspects: flexibility in terms of being able to cope to unexpected beam behaviours [2], [3] legacy of previous version experience [4], [5] and internal powerful diagnostics [6] as in the systems previously used in PEP-II and DAFNE [7].

System Evaluation and Economic Analysis of a Nuclear Reactor Powered High-Temperature Electrolysis Hydrogen-Production Plant

International Nuclear Information System (INIS)

Harvego, E.A.; McKellar, M.G.; Sohal, M.S.; O'Brien, J.E.; Herring, J.S.

2010-01-01

A reference design for a commercial-scale high-temperature electrolysis (HTE) plant for hydrogen production was developed to provide a basis for comparing the HTE concept with other hydrogen production concepts. The reference plant design is driven by a high-temperature helium-cooled nuclear reactor coupled to a direct Brayton power cycle. The reference design reactor power is 600 MWt, with a primary system pressure of 7.0 MPa, and reactor inlet and outlet fluid temperatures of 540 C and 900 C, respectively. The electrolysis unit used to produce hydrogen includes 4,009,177 cells with a per-cell active area of 225 cm2. The optimized design for the reference hydrogen production plant operates at a system pressure of 5.0 MPa, and utilizes an air-sweep system to remove the excess oxygen that is evolved on the anode (oxygen) side of the electrolyzer. The inlet air for the air-sweep system is compressed to the system operating pressure of 5.0 MPa in a four-stage compressor with intercooling. The alternating current (AC) to direct current (DC) conversion efficiency is 96%. The overall system thermal-to-hydrogen production efficiency (based on the lower heating value of the produced hydrogen) is 47.1% at a hydrogen production rate of 2.356 kg/s. An economic analysis of this plant was performed using the standardized H2A Analysis Methodology developed by the Department of Energy (DOE) Hydrogen Program, and using realistic financial and cost estimating assumptions. The results of the economic analysis demonstrated that the HTE hydrogen production plant driven by a high-temperature helium-cooled nuclear power plant can deliver hydrogen at a competitive cost. A cost of $3.23/kg of hydrogen was calculated assuming an internal rate of return of 10%.

Combined heat and power (cogeneration) plant based on renewable energy sources and electrochemical hydrogen systems

Science.gov (United States)

Grigor'ev, S. A.; Grigor'ev, A. S.; Kuleshov, N. V.; Fateev, V. N.; Kuleshov, V. N.

2015-02-01

The layout of a combined heat and power (cogeneration) plant based on renewable energy sources (RESs) and hydrogen electrochemical systems for the accumulation of energy via the direct and inverse conversion of the electrical energy from RESs into the chemical energy of hydrogen with the storage of the latter is described. Some efficient technical solutions on the use of electrochemical hydrogen systems in power engineering for the storage of energy with a cyclic energy conversion efficiency of more than 40% are proposed. It is shown that the storage of energy in the form of hydrogen is environmentally safe and considerably surpasses traditional accumulator batteries by its capacitance characteristics, being especially topical in the prolonged absence of energy supply from RESs, e.g., under the conditions of polar night and breathless weather. To provide the required heat consumption of an object during the peak period, it is proposed to burn some hydrogen in a boiler house.

Variation of the effectiveness of hydrogen water chemistry in a boiling water reactor during power coastdown operations

International Nuclear Information System (INIS)

Yeh Tsungkuang; Wang Meiya; Chu, Charles F.; Chang Ching

2009-01-01

A theoretical model was adapted to evaluate the impact of power coastdown on the water chemistry of a commercial boiling water reactor (BWR) in this work. In principle, the power density of a nuclear reactor upon a power level decrease would immediately be lowered, followed by water chemistry variations due to reduced radiolysis of water and extended coolant residence times in the core and near-core regions. It is currently a common practice for a commercial BWR to adopt hydrogen water chemistry (HWC) for corrosion mitigation. The optimal feedwater hydrogen concentration may be different after a power coastdown is implemented in a BWR. A computer code DEMACE was used in the current study to investigate the impact of various power coastdown levels on major radiolytic species concentrations and electrochemical corrosion potential (ECP) behavior of components in the primary coolant circuit of a domestic reactor operating under either normal water chemistry or HWC. Our analyses indicated that under a rated core flow rate the chemical species concentrations and the ECP did not vary monotonously with decreases in reactor power level at a fixed feedwater hydrogen concentration. In particular, ECP variations basically followed the patterns of hydrogen peroxide in the select regions and exhibited high values at power level of 90% for Reactor X. (author)

Hydrogen Generation, Combustibility and Mitigation in Nuclear Power Plant Systems

International Nuclear Information System (INIS)

Talha, K.A.; El-Sheikh, B.M.; Gad El-Mawla, A.S.

2003-01-01

The nuclear power plant is provided with features to insure safety. The engineered safety features (ESFs) are devoted to set operating conditions under accident conditions. If ESFs fail to apply in some accidents, this would lead to what called severe accidents, and core damage. In this case hydrogen will be generated from different sources particularly from metal-water reactions. Since the containment is the final barrier to protect the environment from the release of radioactive materials; its integrity should not be threatened. In recent years, hydrogen concentration represents a real problem if it exceeds the combustibility limits. This work is devoted to calculate the amount of hydrogen to be generated, indelicate its combustibility and how to inertize the containment using different gases to maintain its integrity and protect the environment from the release of radioactive materials

Super jackstraws and super waterwheels

International Nuclear Information System (INIS)

Cho, Jin-Ho

2007-01-01

We construct various new BPS states of D-branes preserving 8 supersymmetries. These include super Jackstraws (a bunch of scattered D- or (p, q)-strings preserving supersymmetries), and super waterwheels (a number of D2-branes intersecting at generic angles on parallel lines while preserving supersymmetries). Super D-Jackstraws are scattered in various dimensions but are dynamical with all their intersections following a common null direction. Meanwhile, super (p, q)-Jackstraws form a planar static configuration. We show that the SO(2) subgroup of SL(2, R), the group of classical S-duality transformations in IIB theory, can be used to generate this latter configuration of variously charged (p, q)-strings intersecting at various angles. The waterwheel configuration of D2-branes preserves 8 supersymmetries as long as the 'critical' Born-Infeld electric fields are along the common direction

Super capacitors for embarked systems as a storage energy device solution

Energy Technology Data Exchange (ETDEWEB)

Ayad, M.Y.; Rael, S.; Pierfederici, S.; Davat, B. [Institut National Polytechnique, GREEN-INPL-CNRS (UMR 7037), 54 - Vandoeuvre les Nancy (France)

2004-07-01

The management of embarked electrical energy needs a storage system with high dynamic performances, in order to shave transient power peaks and to compensate for the intrinsic limitations of the main source. The use of super-capacitors for this storage system is quite suitable, because of appropriate electrical characteristics (huge capacitance, weak serial resistance, high specific energy, high specific power), of direct storage (energy ready for use), and of easy control by power electronic conversion. This paper deals with the conception and the achievement of two hybrid power sources using super-capacitors as auxiliary storage device. We present the structures, the control principles, and some experimental results. (authors)

Nonlinear Super Integrable Couplings of Super Classical-Boussinesq Hierarchy

Directory of Open Access Journals (Sweden)

Xiuzhi Xing

2014-01-01

Full Text Available Nonlinear integrable couplings of super classical-Boussinesq hierarchy based upon an enlarged matrix Lie super algebra were constructed. Then, its super Hamiltonian structures were established by using super trace identity. As its reduction, nonlinear integrable couplings of the classical integrable hierarchy were obtained.

Studies of super-critical CO2 gas turbine power generation fast reactor (Contract research, translated document)

International Nuclear Information System (INIS)

Kisohara, Naoyuki; Kotake, Shoji; Sakamoto, Toshihiko

2008-08-01

The following studies have been executed for a super-critical CO 2 turbine system of an SFR. (1) Preliminary design of a SFR adopting a super-critical CO 2 cycle turbine. Preliminary system design of an SFR that adopts a super-critical CO 2 cycle turbine has been made. This SFR system eliminates secondary sodium circuits because of no sodium/water reaction. The power generation efficiency of the SFR has been estimated to be approximately 42%. Compared to a conventional SFR that adopts a steam Rankine cycle with secondary sodium circuits, the volume of the reactor building of the SC-CO 2 SFR has been reduced by 20%. (2) Thermal-hydraulic experiment of a super-critical CO 2 cycle loop. A test loop that simulates a super-critical CO 2 whole cycle was fabricated. An electrical heater was used for a heat source of the test loop. The high efficiency of the compressor has been experimentally confirmed near the super-critical region. The temperature efficiencies of PCHE recuperators have been approximately 98-99% (hot leg), and the recuperators have exhibited high heat transfer performance. No significant flow instability has been observed in the test loop operation. (3) Liquid sodium/CO 2 reaction test. Reaction tests have been executed by contacting a small amount of liquid sodium and CO 2 gas. Continuous sodium/CO 2 reactions with flame have occurred at the temperature higher than 570-580degC. Main reaction products have been Na 2 CO 3 and CO gas. The reaction heat has been also measured to be 50-75kJ/Na-mol. (4) Computer code safety analysis for tube failure of sodium/CO 2 heat exchanger. Safety calculation has been done for one double ended guillotine tube failure (1 DEG) of a helical coil type sodium/CO 2 heat exchanger. The analysis has showed that the maximum pressure in the primary sodium circuit is 0.28MPa due to a gas leak. It has been, however, below the allowed level of the primary circuit structural integrity. The void reactivity of the reactor core has

Scope for solar hydrogen power plants along Indian coasts

Science.gov (United States)

Hajra, Debdyut; Mukhopadhyay, Swarnav

2016-09-01

Energy is at the core of economic growth and development in the present day world. But relentless and unchecked use of harmful energy resources like fossil fuels (coil and oil), nuclear energy has taken a toll on mother nature. The energy coffers are being rapidly depleted and within a few years all of them will become empty, leaving nothing for the future generations to build on. Their constant usage has degraded the air quality and given way to land and water pollution. Scientists and world leaders have initiated a call for action to shift our dependence from currently popular energy sources to cleaner and renewable energy sources. Search for such energy sources have been going on for many years. Solar energy, wind energy, ocean energy, tidal energy, biofuel, etc. have caught the attention of people. Another such important which has become popular is 'Solar Hydrogen'. Many visionary scientists have called hydrogen the energy of the future. It is produced from water by direct or indirect use of sunlight in a sustainable manner. This paper discusses the current energy scenario, the importance of solar-hydrogen as a fuel and most importantly the scope for solar hydrogen power plants along Indian coastline.

Power generation in fuel cells using liquid methanol and hydrogen peroxide

Science.gov (United States)

Narayanan, Sekharipuram R. (Inventor); Valdez, Thomas I. (Inventor); Chun, William (Inventor)

2002-01-01

The invention is directed to an encapsulated fuel cell including a methanol source that feeds liquid methanol (CH.sub.3 OH) to an anode. The anode is electrical communication with a load that provides electrical power. The fuel cell also includes a hydrogen peroxide source that feeds liquid hydrogen peroxide (H.sub.2 O.sub.2) to the cathode. The cathode is also in communication with the electrical load. The anode and cathode are in contact with and separated by a proton-conducting polymer electrolyte membrane.

A system of hydrogen powered vehicles with liquid organic hydrides

International Nuclear Information System (INIS)

Taube, M.

1981-07-01

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

On the study of the transfer ionization reactions at super small scattering angles

International Nuclear Information System (INIS)

Popov, Yu.V.; Chuluunbaatar, O.; Vinitskij, S.I.; Ancarani, L.U.; Dal Cappello, C.; Vinitskij, P.S.

2002-01-01

The hypothesis that the reaction p + He → H + He ++ + e at super small scattering angles of hydrogen can be used for purposes of the angular spectroscopy of electron-electron correlations in the target is considered. It is shown that this hypothesis is untenable

On the Study of the Transfer Ionization Reactions at Super Small Scattering Angles

CERN Document Server

Popov, Yu V; Vinitsky, S I; Ancarani, L U; Dal Cappello, C; Vinitsky, P S

2002-01-01

The hypothesis that the reaction p + He\\to H + He^{++} + e at super small scattering angles of hydrogen can be used for purposes of the angular spectroscopy of electron-electron correlations in the target is considered. It is shown that this hypothesis is insolvent.

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

International Nuclear Information System (INIS)

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

1998-01-01

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

A portable system powered with hydrogen and one single air-breathing PEM fuel cell

International Nuclear Information System (INIS)

Fernández-Moreno, J.; Guelbenzu, G.; Martín, A.J.; Folgado, M.A.; Ferreira-Aparicio, P.; Chaparro, A.M.

2013-01-01

Highlights: • A portable system based on hydrogen and single air breathing PEM fuel cell. • Control electronics designed for low single cell voltage (0.5–0.8 V). • Forced air convection and anode purging required to help water management. • Application consisting of a propeller able to display a luminous message. • Up to 20 h autonomy with continuous 1.1 W consumption, using 1 g H 2 . - Abstract: A portable system for power generation based on hydrogen and a single proton exchange membrane fuel cell (PEMFC) has been built and operated. The fuel cell is fed in the anode with hydrogen stored in a metal hydrides cartridge, and in the cathode with oxygen from quiescent ambient air (‘air breathing’). The control electronics of the system performs DC–DC conversion from the low voltage (0.5–0.8 V) and high current output (200–300 mA cm −2 ) of the single fuel cell, up to 3.3 V to power an electronic application. System components assist fuel cell operation, including an electronic valve for anode purging, a fan in front of the open cathode, two supercapacitors for auxiliary power requirements, four LED lights, and a display screen. The influence of the system components on fuel cell behaviour is analyzed. The cathode fan and anodic purging help excess water removal from the electrodes leading to steadier cell response at the expense of extra power consumption. The power system is able to provide above 1 W DC electricity to an external application during 20 h using 1 g of H 2 . An application consisting of a propeller able to display a luminous message is chosen to test system. It is shown that one single air breathing PEM fuel cell powered with hydrogen may provide high energy density and autonomy for portable applications

The hydrogen economy for a sustainable future and the potential contribution of nuclear power

International Nuclear Information System (INIS)

Hardy, C.

2003-01-01

The Hydrogen Economy encompasses the production of hydrogen using a wide range of energy sources, its storage and distribution as an economic and universal energy carrier, and its end use by industry and individuals with negligible emission of pollutants and greenhouse gases. Hydrogen is an energy carrier not a primary energy source, just like electricity is an energy carrier. The advantages of hydrogen as a means of storage and distribution of energy, and the methods of production of hydrogen, are reviewed. Energy sources for hydrogen production include fossil fuels, renewables, hydropower and nuclear power. Hydrogen has many applications in industry, for residential use and for transport by air, land and sea. Fuel cells are showing great promise for conversion of hydrogen into electricity and their development and current status are discussed. Non-energy uses of hydrogen and the safety aspects of hydrogen are also considered. It is concluded that the Hydrogen Economy, especially if coupled to renewable and nuclear energy sources, is a technically viable and economic way of achieving greater energy diversity and security and a sustainable future in this century

Super-adiabatic combustion in Al2O3 and SiC coated porous media for thermoelectric power conversion

International Nuclear Information System (INIS)

Mueller, Kyle T.; Waters, Oliver; Bubnovich, Valeri; Orlovskaya, Nina; Chen, Ruey-Hung

2013-01-01

The combustion of ultra-lean fuel/air mixtures provides an efficient way to convert the chemical energy of hydrocarbons and low-calorific fuels into useful power. Matrix-stabilized porous medium combustion is an advanced technique in which a solid porous medium within the combustion chamber conducts heat from the hot gaseous products in the upstream direction to preheat incoming reactants. This heat recirculation extends the standard flammability limits, allowing the burning of ultra-lean and low-calorific fuel mixtures and resulting a combustion temperature higher than the thermodynamic equilibrium temperature of the mixture (i.e., super-adiabatic combustion). The heat generated by this combustion process can be converted into electricity with thermoelectric generators, which is the goal of this study. The design of a porous media burner coupled with a thermoelectric generator and its testing are presented. The combustion zone media was a highly-porous alumina matrix interposed between upstream and downstream honeycomb structures with pore sizes smaller than the flame quenching distance, preventing the flame from propagating outside of the central section. Experimental results include temperature distributions inside the combustion chamber and across a thermoelectric generator; along with associated current, voltage and power output values. Measurements were obtained for a catalytically inert Al 2 O 3 medium and a SiC coated medium, which was tested for the ability to catalyze the super-adiabatic combustion. The combustion efficiency was obtained for stoichiometric and ultra-lean (near the lean flammability limit) mixtures of CH 4 and air. - Highlights: • Design of a porous burner coupled with a thermoelectric module. • Super-adiabatic combustion in a highly-porous ceramic matrix was investigated. • Both alumina and silicon carbide ceramic surfaces were used as porous media. • Catalytic properties of Al 2 O 3 and SiC ceramic surfaces were studied

Evaluation of power transfer efficiency for a high power inductively coupled radio-frequency hydrogen ion source

Science.gov (United States)

Jain, P.; Recchia, M.; Cavenago, M.; Fantz, U.; Gaio, E.; Kraus, W.; Maistrello, A.; Veltri, P.

2018-04-01

Neutral beam injection (NBI) for plasma heating and current drive is necessary for International Thermonuclear Experimental reactor (ITER) tokamak. Due to its various advantages, a radio frequency (RF) driven plasma source type was selected as a reference ion source for the ITER heating NBI. The ITER relevant RF negative ion sources are inductively coupled (IC) devices whose operational working frequency has been chosen to be 1 MHz and are characterized by high RF power density (˜9.4 W cm-3) and low operational pressure (around 0.3 Pa). The RF field is produced by a coil in a cylindrical chamber leading to a plasma generation followed by its expansion inside the chamber. This paper recalls different concepts based on which a methodology is developed to evaluate the efficiency of the RF power transfer to hydrogen plasma. This efficiency is then analyzed as a function of the working frequency and in dependence of other operating source and plasma parameters. The study is applied to a high power IC RF hydrogen ion source which is similar to one simplified driver of the ELISE source (half the size of the ITER NBI source).

Super high field ohmically heated tokamak operation

International Nuclear Information System (INIS)

Cohn, D.R.; Bromberg, L.; Leclaire, R.J.; Potok, R.E.; Jassby, D.L.

1986-01-01

The authors discuss a super high field mode of tokamak operation that uses ohmic heating or near ohmic heating to ignition. The super high field mode of operation uses very high values of Β/sup 2/α, where Β is the magnetic field and a is the minor radius (Β/sup 2/α > 100 T/sup 2/m). We analyze copper magnet devices with major radii from 1.7 to 3.0 meters. Minimizing or eliminating the need for auxiliary heating has the potential advantages of reducing uncertainty in extrapolating the energy confinement time of current tokamak devices, and reducing engineering problems associated with large auxiliary heating requirements. It may be possible to heat relatively short pulse, inertially cooled tokamaks to ignition with ohmic power alone. However, there may be advantages in using a very small amount of auxiliary power (less than the ohmic heating power) to boost the ohmic heating and provide a faster start-up, expecially in relatively compact devices

Hydrogen combustion study in the containment of Atucha-I nuclear power plant

International Nuclear Information System (INIS)

Baron, J.H.; Gonzalez Videla, E.

1997-01-01

In this paper the combustion of hydrogen was modeled and studied in the containment vessel of the Atucha I nuclear power station using the CONTAIN package. The hydrogen comes from the oxidation of metallic materials during the severe accidents proposed. The CONTAIN package is an integrated tool that analyzes the physical, chemical and radiation conditions that affect the containment structure of the radioactive materials unloaded from the primary system during a severe accident in the reactor. (author) [es

Hydrogen preheating through waste heat recovery of an open-cathode PEM fuel cell leading to power output improvement

International Nuclear Information System (INIS)

Mohamed, W.A.N.W.; Kamikl, M. Haziq M.

2016-01-01

Highlights: • A study on the effect of hydrogen preheating using waste heat for low temperature PEM fuel cells. • Theoretical, experimental and analytical framework was established. • The maximum electrical power output increases by 8–10% under specific operating conditions. • Open loop hydrogen supply gives a better performance than closed loop. • The waste heat utilization is less than 10% due to heat capacity limitations. - Abstract: The electrochemical reaction kinetics in a Polymer Electrolyte Membrane (PEM) fuel cell is highly influenced by the reactants supply pressures and electrode temperatures. For an open cathode PEM fuel cell stack, the power output is constrained due to the use of air simultaneously as reactant and coolant. Optimal stack operation temperatures are not achieved especially at low to medium power outputs. Based on the ideal gas law, higher reactant temperatures would lead to higher pressures and subsequently improve the reaction kinetics. The hydrogen supply temperature and its pressure can be increased by preheating; thus, slightly offsetting the limitation of low operating stack temperatures. The exit air stream offers an internal source of waste heat for the hydrogen preheating purpose. In this study, a PEM open-cathode fuel cell was used to experimentally evaluate the performance of hydrogen preheating based on two waste heat recovery approaches: (1) open-loop and (2) closed loop hydrogen flow. The stack waste heat was channelled into a heat exchanger to preheat the hydrogen line before it is being supplied (open loop) or resupplied (closed loop) into the stack. At a constant 0.3 bar hydrogen supply pressure, the preheating increases the hydrogen temperature in the range of 2–13 °C which was dependant on the stack power output and cathode air flow rates. The achievable maximum stack power was increased by 8% for the closed loop and 10% for the open loop. Due to the small hydrogen flow rates, the waste heat utilization

The super-classical-Boussinesq hierarchy and its super-Hamiltonian structure

International Nuclear Information System (INIS)

Si-Xing, Tao; Tie-Cheng, Xia

2010-01-01

Based on the constructed Lie superalgebra, the super-classical-Boussinesq hierarchy is obtained. Then, its super-Hamiltonian structure is obtained by making use of super-trace identity. Furthermore, the super-classical-Boussinesq hierarchy is also integrable in the sense of Liouville. (general)

Hydrogen generation by nuclear power for sustainable development in the 21-st century

International Nuclear Information System (INIS)

Bilegan, Iosif Constantin; Pall, Stefan

2002-01-01

Hydrogen is the main non-polluting fuel. It is produced by natural gas steam reforming, water electrolysis and thermonuclear processes. Currently, 4% of the hydrogen world production is obtained by water electrolysis. The use of nuclear power for hydrogen production avoids the generation of greenhouse gases and the dependence of primary external energy sources. The US is currently developing a modular reactor for hydrogen production and water desalination, STAR - H 2 (Secure Transportable Autonomous Reactor for Hydrogen production) with fast neutrons, lead cooling and passive safety systems operating at a temperature of 780 deg C. Also, a Russian reactor of the same type is operated at 540 deg C. China and India joint industrial countries like France, Japan, Russia and US in recognizing that any strategies aiming at a future with clean energy implies the nuclear energy

Storage the electric power: yes, it is indispensable and it is possible. Why, where, how

International Nuclear Information System (INIS)

2003-01-01

This document describes the main characteristics of various electric power storage methods and their application domains. The large-scale storages include the hydraulic systems, those using compressed air, the batteries or those implementing a thermal way. The small-scale storages are electrochemical as the accumulators, the super-capacitors, mechanical as the flywheel, magnetic or also by the hydrogen use. The first part presents the necessity of the electric power storage, the second part the places of these storage. The third part details the forms of storage. (A.L.B.)

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 %.

Alkaline sodium borohydride gel as a hydrogen source for PEMFC or an energy carrier for NaBH{sub 4}-air battery

Energy Technology Data Exchange (ETDEWEB)

Liu, B.H. [Department of Materials and Engineering, Zhejiang University (China); Li, Z.P.; Chen, L.L. [Department of Chemical and Biochemical Engineering, Zhejiang University, Hangzhou 310027 (China)

2008-05-15

In this preliminary study, we tried to use sodium polyacrylate as the super absorbent polymer to form alkaline NaBH{sub 4} gel and explored its possibilities for borohydride hydrolysis and borohydride electro-oxidation. It was found that the absorption capacity of sodium polyacrylate decreased with increasing NaBH{sub 4} concentration. The formed gel was rather stable in the sealed vessel but tended to slowly decompose in open air. Hydrogen generation from the gel was carried out using CoCl{sub 2} catalyst precursor solutions. Hydrogen generation rate from the alkaline NaBH{sub 4} gel was found to be higher and impurities in hydrogen were less than that from the alkaline NaBH{sub 4} solution. The NaBH{sub 4} gel also successfully powered a NaBH{sub 4}-air battery. (author)

Fuel Cell/ Super-capacitor power management system assessment and Lifetime Cost study in a 500kVA UPS

Directory of Open Access Journals (Sweden)

Imen Ben Amira

2018-03-01

Full Text Available A 500 KVA Uninterruptible power supply (UPS using Fuel Cells (FC and super-capacitors (SCs was studied with the worst case of 10 minutes and eight hours of interruption per day. A power management system was established to control the FC and the SCs in order to extract the hybridization benefits with a comparison between a Proton exchange membrane FC (PEMFC working alone and another combined with SCs. Moreover, possible FC degradations were discussed. The start/stop cycling, the high-power loads and load changes degradations were taken into consideration in order to estimate the FC lifetime span using a prediction formula. Besides, the FC costs were studied to estimate the best average cost. Finally, the SCs filter constant time and their charging currents were revealed.

Hydrogen: the great debate. 'Power to Gas - how to cope with the challenge of electricity storage?; Hydrogen in energy transition: which challenges to be faced?; Hydrogen, essential today, indispensable tomorrow; Electrolytic hydrogen, a solution for energy transition?; Development of high power electrolysis systems: need and approach; Hydrogen as energy vector, Potential and stakes: a perspective; The Toyota Fuel Cell System: a new era for the automotive industry; Three key factors: production, applications to mobility, and public acceptance; Hydrogen, benevolent fairy or tempting demon

International Nuclear Information System (INIS)

Hauet, Jean-Pierre; Boucly, Philippe; Beeker, Etienne; Mauberger, Pascal; Quint, Aliette; Pierre, Helene; Lucchese, Paul; Bouillon-Delporte, Valerie; Chauvet, Bertrand; Brisse, Annabelle; Gautier, Ludmila; Hercberg, Sylvain; De Volder, Marc; Gruson, Jean-Francois; Marion, Pierre; Grellier, Sebastien; Devezeaux, Jean-Guy; Mansilla, Christine; Le Net, Elisabeth; Le Duigou, Alain; Maire, Jacques

2015-01-01

This publication proposes a set of contributions which address various issues related to the development of the use of hydrogen as an energy source. More precisely, these contributions discuss how to face the challenge of electricity storage by using the Power-to-Gas technology, the challenges to be faced regarding the role of hydrogen in energy transition, the essential current role of hydrogen and its indispensable role for tomorrow, the possible role of electrolytic hydrogen as a solution for energy transition, the need of and the approach to a development of high power electrolysis systems, the potential and stakes of hydrogen as an energy vector, the Toyota fuel cell system as a sign for new era for automotive industry, the three main factors (production, applications to mobility, and public acceptance) for the use of hydrogen in energy transition, and the role of hydrogen perceived either as a benevolent fairy or a tempting demon

Dry cleaning of fluorocarbon residues by low-power electron cyclotron resonance hydrogen plasma

CERN Document Server

Lim, S H; Yuh, H K; Yoon Eui Joon; Lee, S I

1988-01-01

A low-power ( 50 W) electron cyclotron resonance hydrogen plasma cleaning process was demonstrated for the removal of fluorocarbon residue layers formed by reactive ion etching of silicon dioxide. The absence of residue layers was confirmed by in-situ reflection high energy electron diffraction and cross-sectional high resolution transmission electron microscopy. The ECR hydrogen plasma cleaning was applied to contact cleaning of a contact string structure, resulting in comparable contact resistance arising during by a conventional contact cleaning procedure. Ion-assisted chemical reaction involving reactive atomic hydrogen species generated in the plasma is attributed for the removal of fluorocarbon residue layers.

Workshop on Hydrogen Storage and Generation for Medium-Power and -Energy Applications

National Research Council Canada - National Science Library

Matthews, Michael

1998-01-01

This report summarizes the Workshop on Hydrogen Storage and Generation Technologies for Medium-Power and -Energy Applications which was held on April 8-10, 1997 at the Radisson Hotel Orlando Airport in Orlando, Florida...

A Renewably Powered Hydrogen Generation and Fueling Station Community Project

Science.gov (United States)

Lyons, Valerie J.; Sekura, Linda S.; Prokopius, Paul; Theirl, Susan

2009-01-01

The proposed project goal is to encourage the use of renewable energy and clean fuel technologies for transportation and other applications while generating economic development. This can be done by creating an incubator for collaborators, and creating a manufacturing hub for the energy economy of the future by training both white- and blue-collar workers for the new energy economy. Hydrogen electrolyzer fueling stations could be mass-produced, shipped and installed in collaboration with renewable energy power stations, or installed connected to the grid with renewable power added later.

DE PODER NULO A SUPERPODER: O JUDICIÁRIO DE MONTESQUIEU, REVISITADO | FROM NULL TO SUPER-POWER: MONTESQUIEU’S JUDICIARY REVIEWED

Directory of Open Access Journals (Sweden)

Sandro Luís Tomás Ballande Romanelli

2016-08-01

Full Text Available This article discusses the Judiciary within the doctrine of separation of powers, aiming to provide historical and political data that could explain judicial protagonism. This is achieved through book reviews of contemporary political science literature and classic authors from the 18 th century. Therefore, it aims to examine in depth some chapters of Montesquieu’s “Spirit of laws” classic book, expressing how its theory of judicial power was deeply linked with ancient régime’s judicial system, in a context where 18 th century French Judiciary Power was a great source of threat to both political and legislative powers. The paper addresses how the American Constitution bended the original theory, moving from an absolute separation of powers towards a super-powered Judiciary in defence of individual liberties, acting as counterbalance to state assemblies and local political powers. In conclusion, it stands that Judicial Power protagonism doesn’t violate the classic theory of separation of powers.

Steam generator development in France for the Super Phenix project

International Nuclear Information System (INIS)

Robin, M.G.

1975-01-01

'Steam Generator Development for Super Phenix Project'. The development program of steam generators studied by Fives-Cail Babcock and Stein Industrie Companies, jointly with CEA end EDF, for the Super Phenix 1200 MWe Fast Breeder Power Plant, is presented. The main characteristics of both sodium heated steam generators are emphasized and experimental studies related to their key features are reported. (author)

SUPERNOVA LIGHT CURVES POWERED BY FALLBACK ACCRETION

Energy Technology Data Exchange (ETDEWEB)

Dexter, Jason; Kasen, Daniel, E-mail: jdexter@berkeley.edu [Departments of Physics and Astronomy, University of California, Berkeley, CA 94720 (United States)

2013-07-20

Some fraction of the material ejected in a core collapse supernova explosion may remain bound to the compact remnant, and eventually turn around and fall back. We show that the late time ({approx}>days) power potentially associated with the accretion of this 'fallback' material could significantly affect the optical light curve, in some cases producing super-luminous or otherwise peculiar supernovae. We use spherically symmetric hydrodynamical models to estimate the accretion rate at late times for a range of progenitor masses and radii and explosion energies. The accretion rate onto the proto-neutron star or black hole decreases as M-dot {proportional_to}t{sup -5/3} at late times, but its normalization can be significantly enhanced at low explosion energies, in very massive stars, or if a strong reverse shock wave forms at the helium/hydrogen interface in the progenitor. If the resulting super-Eddington accretion drives an outflow which thermalizes in the outgoing ejecta, the supernova debris will be re-energized at a time when photons can diffuse out efficiently. The resulting light curves are different and more diverse than previous fallback supernova models which ignored the input of accretion power and produced short-lived, dim transients. The possible outcomes when fallback accretion power is significant include super-luminous ({approx}> 10{sup 44} erg s{sup -1}) Type II events of both short and long durations, as well as luminous Type I events from compact stars that may have experienced significant mass loss. Accretion power may unbind the remaining infalling material, causing a sudden decrease in the brightness of some long duration Type II events. This scenario may be relevant for explaining some of the recently discovered classes of peculiar and rare supernovae.

Search for an evaporating ocean on the super-Earth HIP 116454b

Science.gov (United States)

Bourrier, Vincent

2017-08-01

The super-Earth HIP116454b was the first exoplanet detected by the K2 mission, in transit across a bright and nearby K1 dwarf (V=10.2, d=55 pc). The low density of the planet suggests it must have at least 30% water or a 0.5% H-He envelope. Given the strong XUV irradiation from the young (2 Gyr) host star, this H-He envelope should have been lost through evaporation in a few hundred millions year, suggesting that HIP 116454b likely contains a large mass fraction of water. The shallow transit depth makes difficult the search for water vapor in the lower atmosphere with HST/WFC3. The moderate orbital distance of this warm ( 700 K) planet favors the formation of a super-critical steam envelope, which should be promptly dissociated at high altitude by the XUV irradiation and become observable as hydrogen flowing within and beyond the Roche lobe. The host star is similar to HD 189733, host to an evaporating hot Jupiter, and numerical simulations of HIP116454b show that the hydrogen exosphere resulting from the dissociation of water is observable with HST/STIS at Ly-alpha. The detection of this exosphere would be the first signature of an evolved evaporating ocean on an extrasolar planet, as well as the first validation of internal structure models of exoplanets in this mass regime. It would also determine how to best search for water in the lower atmosphere of HIP116454b with the JWST. A non-detection of escaping hydrogen, as with 55 Cnc e and HD 97658b, would bring useful constraints on the nature of the planetary atmosphere, the evolutionary path of close-in super-Earths, and the progenitors of the rocky evaporation remnants detected by Kepler.

Full-power test of a string of magnets comprising a half-cell of the Superconducting Super Collider

International Nuclear Information System (INIS)

Burgett, W.; Christianson, M.; Coombes, R.

1992-10-01

In this paper we describe the full-powered operation of a string of industrially-fabricated magnets comprising a half-cell of the Superconducting Super Collider (SSC). The completion of these tests marks the first successful operation of a major SSC subsystem. The five 15-m long dipole magnets in the string had an aperture of 50 mm and the single 5-m long quadrupole aperture was 40 mm. Power and cryogenic connections were made to the string through spool pieces that are prototypes for SSC operations. The string was cooled to cryogenic temperatures in early July, 1992, and power tests were performed at progressively higher currents up to the nominal SSC operating point above 6500 amperes achieved in mid-August. In this paper we report on the electrical and cryogenic performance of the string components and the quench protection system during these initial tests

An examination of isolated, stationary, hydrogen power systems supplied by renewables: component and system issues and criteria necessary for successful worldwide deployment

Energy Technology Data Exchange (ETDEWEB)

Rambach, G. D. [Energy and Environmental Engineering Center, Desert Research Institute, Reno, NV (United States)

1999-12-01

The premise of this paper is that remote, stationary power systems, based on indigenous renewable energy sources, are an ideal market entry opportunity for hydrogen, but that the deployment of isolated power systems relying on hydrogen as the energy storage medium requires complex and comprehensive planning and design considerations to provide for successful market entry strategies and appropriate systems engineering. Accordingly, this paper sets out to discuss the criteria and the framework necessary to determine how to successfully deploy any specific system or to plan a global marketing strategy. Details of the indigenous intermittent energy sources (wind turbines, solar photovoltaic, micro-hydroelectric, etc), primary power-to-hydrogen conversion systems, hydrogen storage methods, and hydrogen-to-electricity conversion systems (hydrogen-internal combustion engine generator set, hydrogen fuel cells) are described, along with the criteria for technically and commercially successful deployment of any renewable utility power system that employs energy storage.2 refs., 4 figs.

Optimal Sizing of a Photovoltaic-Hydrogen Power System for HALE Aircraft by means of Particle Swarm Optimization

Directory of Open Access Journals (Sweden)

Victor M. Sanchez

2015-01-01

Full Text Available Over the last decade there has been a growing interest in the research of feasibility to use high altitude long endurance (HALE aircrafts in order to provide mobile communications. The use of HALEs for telecommunication networks has the potential to deliver a wide range of communication services (from high-quality voice to high-definition videos, as well as high-data-rate wireless channels cost effectively. One of the main challenges of this technology is to design its power supply system, which must provide the enough energy for long time flights in a reliable way. In this paper a photovoltaic/hydrogen system is proposed as power system for a HALE aircraft due its high power density characteristic. In order to obtain the optimal sizing for photovoltaic/hydrogen system a particle swarm optimizer (PSO is used. As a case study, theoretical design of the photovoltaic/hydrogen power system for three different HALE aircrafts located at 18° latitude is presented. At this latitude, the range of solar radiation intensity was from 310 to 450 Wh/sq·m/day. The results obtained show that the photovoltaic/hydrogen systems calculated by PSO can operate during one year with efficacies ranging between 45.82% and 47.81%. The obtained sizing result ensures that the photovoltaic/hydrogen system supplies adequate energy for HALE aircrafts.

Study of a molten carbonate fuel cell combined heat, hydrogen and power system

International Nuclear Information System (INIS)

Hamad, Tarek A.; Agll, Abdulhakim A.; Hamad, Yousif M.; Bapat, Sushrut; Thomas, Mathew; Martin, Kevin B.; Sheffield, John W.

2014-01-01

To address the problem of fossil fuel usage and high greenhouse gas emissions at the Missouri University of Science and Technology campus, using of alternative fuels and renewable energy sources can lower energy consumption and greenhouse gas emissions. Biogas, produced by anaerobic digestion of wastewater, organic waste, agricultural waste, industrial waste, and animal by-products is a potential source of renewable energy. In this work, we have discussed the design of CHHP (combined heat, hydrogen and power) system for the campus using local resources. An energy flow and resource availability study is performed to identify the type and source of feedstock required to continuously run the fuel cell system at peak capacity. Following the resource assessment study, the team selects FuelCell Energy DFC (direct fuel cell) 1500™ unit as a molten carbonate fuel cell. The CHHP system provides electricity to power the university campus, thermal energy for heating the anaerobic digester, and hydrogen for transportation, back-up power and other needs. In conclusion, the CHHP system will be able to reduce fossil fuel usage, and greenhouse gas emissions at the university campus. - Highlights: • A molten carbonate fuel cell tri-generation by using anaerobic digestion system. • Anaerobic digestion system will be able to supply fuel for the DFC1500™ unit. • Use locally available feedstock to production electric power, hydrogen and heat. • Application energy end-uses on the university. • CHHP system will reduce energy consumption, fossil fuel usage, and GHG emissions

Requirements for a Hydrogen Powered All-Electric Manned Helicopter

Science.gov (United States)

Datta, Anubhav

2012-01-01

The objective of this paper is to set propulsion system targets for an all-electric manned helicopter of ultra-light utility class to achieve performance comparable to combustion engines. The approach is to begin with a current two-seat helicopter (Robinson R 22 Beta II-like), design an all-electric power plant as replacement for its existing piston engine, and study performance of the new all-electric aircraft. The new power plant consists of high-pressure Proton Exchange Membrane fuel cells, hydrogen stored in 700 bar type-4 tanks, lithium-ion batteries, and an AC synchronous permanent magnet motor. The aircraft and the transmission are assumed to remain the same. The paper surveys the state of the art in each of these areas, synthesizes a power plant using best available technologies in each, examines the performance achievable by such a power plant, identifies key barriers, and sets future technology targets to achieve performance at par with current internal combustion engines.

The hydrogen village: building hydrogen and fuel cell opportunities

International Nuclear Information System (INIS)

Smith, R.

2006-01-01

The presentation addressed the progress the Hydrogen Village Program has made in its first 24 months of existence and will provide an understanding of the development of new markets for emerging Hydrogen and Fuel Cell technologies based on first hand, real world experience. The Hydrogen Village (H2V) is an End User driven, Market Development Program designed to accelerate the sustainable commercialization of hydrogen and fuel cell technologies through awareness, education and early deployments throughout the greater Toronto area (GTA). The program is a collaborative public-private partnership of some 35 companies from a broad cross section of industry administered through Hydrogen and Fuel Cells Canada and funded by the Governments of Canada and Ontario. The intent of the H2V is to develop markets for Hydrogen and Fuel Cell technologies that benefit the local and global community. The following aspects of market development are specifically targeted: 1) Deployments: of near market technologies in all aspects of community life (stationary and mobile). All applications must be placed within the community and contact peoples in their day-to-day activity. End user involvement is critical to ensure that the applications chosen have a commercial justification and contribute to the complementary growth of the market. 2) Development: of a coordinated hydrogen delivery and equipment service infrastructure. The infrastructure will develop following the principles of conservation and sustainability. 3) Human and societal factors: - Public and Corporate policy, public education, Codes/ Standards/ Regulations - Opportunity for real world implementation and feedback on developing codes and standards - Build awareness among regulatory groups, public, and the media. The GTA Hydrogen Village is already well under way with strategically located projects covering a wide range of hydrogen and fuel cell applications including: Residential heat and power generation using solid oxide

Nuclear power and hydrogen

International Nuclear Information System (INIS)

Welch, Robert.

1982-06-01

Ontario has been using CANDU reactors to produce electricity since 1962. The province does not have an electricity shortage, but it does have a shortage of liquid fuels. The government of Ontario is encouraging research into the production of hydrogen using electricity generated by a dedicated nuclear plant, and the safe and economical use of hydrogen both in the production of synthetic petroleum fuels and as a fuel in its own right

Mapping ionospheric backscatter measured by the SuperDARN HF radars – Part 2: Assessing SuperDARN virtual height models

Directory of Open Access Journals (Sweden)

T. K. Yeoman

2008-05-01

Full Text Available The Super Dual Auroral Radar Network (SuperDARN network of HF coherent backscatter radars form a unique global diagnostic of large-scale ionospheric and magnetospheric dynamics in the Northern and Southern Hemispheres. Currently the ground projections of the HF radar returns are routinely determined by a simple rangefinding algorithm, which takes no account of the prevailing, or indeed the average, HF propagation conditions. This is in spite of the fact that both direct E- and F-region backscatter and 1½-hop E- and F-region backscatter are commonly used in geophysical interpretation of the data. In a companion paper, Chisham et al. (2008 have suggested a new virtual height model for SuperDARN, based on average measured propagation paths. Over shorter propagation paths the existing rangefinding algorithm is adequate, but mapping errors become significant for longer paths where the roundness of the Earth becomes important, and a correct assumption of virtual height becomes more difficult. The SuperDARN radar at Hankasalmi has a propagation path to high power HF ionospheric modification facilities at both Tromsø on a ½-hop path and SPEAR on a 1½-hop path. The SuperDARN radar at Þykkvibǽr has propagation paths to both facilities over 1½-hop paths. These paths provide an opportunity to quantitatively test the available SuperDARN virtual height models. It is also possible to use HF radar backscatter which has been artificially induced by the ionospheric heaters as an accurate calibration point for the Hankasalmi elevation angle of arrival data, providing a range correction algorithm for the SuperDARN radars which directly uses elevation angle. These developments enable the accurate mappings of the SuperDARN electric field measurements which are required for the growing number of multi-instrument studies of the Earth's ionosphere and magnetosphere.

Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power

International Nuclear Information System (INIS)

Brown, L.C.; Funk, J.F.; Showalter, S.K.

1999-01-01

OAK B188 Initial Screening of Thermochemical Water-Splitting Cycles for High Efficiency Generation of Hydrogen Fuels Using Nuclear Power There is currently no large scale, cost-effective, environmentally attractive hydrogen production process, nor is such a process available for commercialization. Hydrogen is a promising energy carrier, which potentially could replace the fossil fuels used in the transportation sector of our economy. Fossil fuels are polluting and carbon dioxide emissions from their combustion are thought to be responsible for global warming. The purpose of this work is to determine the potential for efficient, cost-effective, large-scale production of hydrogen utilizing high temperature heat from an advanced nuclear power station. Almost 800 literature references were located which pertain to thermochemical production of hydrogen from water and over 100 thermochemical watersplitting cycles were examined. Using defined criteria and quantifiable metrics, 25 cycles have been selected for more detailed study

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

Energy Technology Data Exchange (ETDEWEB)

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

2009-01-15

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

An appealing photo-powered multi-functional energy system for the poly-generation of hydrogen and electricity

Science.gov (United States)

Tang, Tiantian; Li, Kan; Shen, Zhemin; Sun, Tonghua; Wang, Yalin; Jia, Jinping

2015-10-01

This paper focuses on a photo-powered poly-generation system (PPS) that is powered by the photocatalytic oxidation of organic substrate to produce hydrogen energy and electrical energy synchronously. This particular device runs entirely on light energy and chemical energy of substrate without external voltage. The performance measurements and optimization experiments are all investigated by using the low concentration of pure ethanol (EtOH) solution. Compared with the conventional submerged reactor for the photogeneration of hydrogen, the hydrogen and the electric current obtained in the constructed PPS are all relatively stable in experimental period and the numerical values detected are many times higher than that of the former by using various simulated ethanol waste liquid. When using Chinese rice wine as substrate at the same ethanol content level (i.e., 0.1 mol L-1), the production of hydrogen is close to that of the pure ethanol solution in the constructed PPS, but no hydrogen is detected in the conventional submerged reactor. These results demonstrate that the constructed PPS could effectively utilize light energy and perform good capability in poly-generation of hydrogen and electricity.

Production of Jet Fuel-Range Hydrocarbons from Hydrodeoxygenation of Lignin over Super Lewis Acid Combined with Metal Catalysts

International Nuclear Information System (INIS)

Wang, Hongliang; Wang, Huamin; Kuhn, Eric; Tucker, Melvin P.; Yang, Bin

2017-01-01

Super Lewis acids containing the triflate anion [e.g., Hf(OTf) 4 , Ln(OTf) 3 , In(OTf) 3 , Al(OTf) 3 ] and noble metal catalysts (e.g., Ru/C, Ru/Al2O 3 ) formed efficient catalytic systems to generate saturated hydrocarbons from lignin in high yields. In such catalytic systems, the metal triflates mediated rapid ether bond cleavage through selective bonding to etheric oxygens while the noble metal catalyzed subsequent hydrodeoxygenation (HDO) reactions. Near theoretical yields of hydrocarbons were produced from lignin model compounds by the combined catalysis of Hf(OTf)4 and ruthenium-based catalysts. When a technical lignin derived from a pilot-scale biorefinery was used, more than 30 wt % of the hydrocarbons produced with this catalytic system were cyclohexane and alkylcyclohexanes in the jet fuel range. Super Lewis acids are postulated to strongly interact with lignin substrates by protonating hydroxyl groups and ether linkages, forming intermediate species that enhance hydrogenation catalysis by supported noble metal catalysts. Meanwhile, the hydrogenation of aromatic rings by the noble metal catalysts can promote oxygenation reactions catalyzed by super Lewis acids.

Production of Jet Fuel-Range Hydrocarbons from Hydrodeoxygenation of Lignin over Super Lewis Acid Combined with Metal Catalysts

Energy Technology Data Exchange (ETDEWEB)

Wang, Hongliang [Department of Biological Systems Engineering, Washington State University, Richland WA 99354 USA; Current address: Center of Biomass Engineering/College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193 PR China; Wang, Huamin [Pacific Northwest National Laboratory, 902 Battelle Boulevard Richland WA 99354 USA; Kuhn, Eric [National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway Golden CO 80401 USA; Tucker, Melvin P. [National Bioenergy Center, National Renewable Energy Laboratory, 15013 Denver West Parkway Golden CO 80401 USA; Yang, Bin [Department of Biological Systems Engineering, Washington State University, Richland WA 99354 USA

2017-11-14

Super Lewis acids containing the triflate anion (e.g. Hf(OTf)4, Ln(OTf)3, Al(OTf)3) and noble metal catalysts (e.g. Ru/C, Ru/Al2O3) formed efficient catalytic systems to generate saturated hydrocarbons from lignin in high yields. In such catalytic systems, the metal triflates mediated rapid ether bond cleavage via selective bonding to etheric oxygens while the noble metal catalysed subsequent hydrodeoxygenation (HDO) reactions. Near theoretical yields of hydrocarbons were produced from lignin model compounds by the combined catalysis of Hf(OTf)4 and ruthenium-based catalysts. When a technical lignin derived from a pilot-scale biorefinery was used, more than 30 wt% of the hydrocarbons produced with this catalytic system were cyclohexane and alkylcyclohexanes in the jet fuel range. Super Lewis acids are postulated to strongly interact with lignin substrates via protonating hydroxyls and ether linkages, forming intermediate species that enhance hydrogenation catalysis by supported noble metal catalysts. Meanwhile, the hydrogenation of aromatic rings by the noble metal catalysts can promote oxygenation reactions catalysed by super Lewis acids.

Thermally regenerative hydrogen/oxygen fuel cell power cycles

Science.gov (United States)

Morehouse, J. H.

1986-01-01

Two innovative thermodynamic power cycles are analytically examined for future engineering feasibility. The power cycles use a hydrogen-oxygen fuel cell for electrical energy production and use the thermal dissociation of water for regeneration of the hydrogen and oxygen. The TDS (thermal dissociation system) uses a thermal energy input at over 2000 K to thermally dissociate the water. The other cycle, the HTE (high temperature electrolyzer) system, dissociates the water using an electrolyzer operating at high temperature (1300 K) which receives its electrical energy from the fuel cell. The primary advantages of these cycles is that they are basically a no moving parts system, thus having the potential for long life and high reliability, and they have the potential for high thermal efficiency. Both cycles are shown to be classical heat engines with ideal efficiency close to Carnot cycle efficiency. The feasibility of constructing actual cycles is investigated by examining process irreversibilities and device efficiencies for the two types of cycles. The results show that while the processes and devices of the 2000 K TDS exceed current technology limits, the high temperature electrolyzer system appears to be a state-of-the-art technology development. The requirements for very high electrolyzer and fuel cell efficiencies are seen as determining the feasbility of the HTE system, and these high efficiency devices are currently being developed. It is concluded that a proof-of-concept HTE system experiment can and should be conducted.

Meeting the near-term demand for hydrogen using nuclear energy in competitive power markets

International Nuclear Information System (INIS)

Miller, A.I.; Duffey, R.B.

2004-01-01

Hydrogen is becoming the reference fuel for future transportation and the timetable for its adoption is shortening. However, to deploy its full potential, hydrogen production either directly or indirectly needs to satisfy three criteria: no associated emissions, including CO 2 ; wide availability; and affordability. This creates a window of great opportunity within the next 15 years for nuclear energy to provide the backbone of hydrogen-based energy systems. But nuclear must establish its hydrogen generating role long before the widespread deployment of Gen IV high-temperature reactors, with their possibility of producing hydrogen directly by heat rather than electricity. For Gen IV the major factors will be efficiency and economic cost, particularly if centralized storage is needed and/or credits for avoided emissions and/or oxygen sales. In the interim, despite its apparently lower overall efficiency, water electrolysis is the only available technology today able to meet the first and second criteria. The third criterion includes costs of electrolysis and electricity. The primary requirements for affordable electrolysis are low capital cost and high utilisation. Consequently, the electricity supply must enable high utilisation as well as being itself low-cost and emissions-free. Evolved Gen III+ nuclear technologies can produce electricity on large scales and at rates competitive with today's CO 2 -emitting, fossil-fuelled technologies. As an example of electrolytic hydrogen's potential, we show competitive deployment in a typical competitive power market. Among the attractions of this approach are reactors supplying a base-loaded market - though permitting occasional, opportunistic diversion of electricity during price spikes on the power grid - and easy delivery of hydrogen to widely distributed users. Gen IV systems with multiple product streams and higher efficiency (e.g., the SCWR) can also be envisaged which can use competitive energy markets to advantage

A super soliton connection

International Nuclear Information System (INIS)

Gurses, M.; Oguz, O.

1985-07-01

Integrable super non-linear classical partial differential equations are considered. A super s1(2,R) algebra valued connection 1-form is constructed. It is shown that curvature 2-form of this super connection vanishes by virtue of the integrable super equations of motion. A super extension of the AKNS scheme is presented and a class of super extension of the Lax hierarchy and super non-linear Schroedinger equation are found. O(N) extension and the Baecklund transformations of the above super equations are also considered. (author)

Super-resolution fluorescence microscopy by stepwise optical saturation

Science.gov (United States)

Zhang, Yide; Nallathamby, Prakash D.; Vigil, Genevieve D.; Khan, Aamir A.; Mason, Devon E.; Boerckel, Joel D.; Roeder, Ryan K.; Howard, Scott S.

2018-01-01

Super-resolution fluorescence microscopy is an important tool in biomedical research for its ability to discern features smaller than the diffraction limit. However, due to its difficult implementation and high cost, the super-resolution microscopy is not feasible in many applications. In this paper, we propose and demonstrate a saturation-based super-resolution fluorescence microscopy technique that can be easily implemented and requires neither additional hardware nor complex post-processing. The method is based on the principle of stepwise optical saturation (SOS), where M steps of raw fluorescence images are linearly combined to generate an image with a M-fold increase in resolution compared with conventional diffraction-limited images. For example, linearly combining (scaling and subtracting) two images obtained at regular powers extends the resolution by a factor of 1.4 beyond the diffraction limit. The resolution improvement in SOS microscopy is theoretically infinite but practically is limited by the signal-to-noise ratio. We perform simulations and experimentally demonstrate super-resolution microscopy with both one-photon (confocal) and multiphoton excitation fluorescence. We show that with the multiphoton modality, the SOS microscopy can provide super-resolution imaging deep in scattering samples. PMID:29675306

Hydrogen and nuclear power

Energy Technology Data Exchange (ETDEWEB)

Lucas, N J.D.

1976-03-01

There is much debate about the form and availability of energy supplies in the future. It is assumed that nuclear fuel is the only source of controlled energy. Energy inputs from the sun, the wind, the waves, the tides, and other sources not available in the form of fuels are not excluded. In this situation it has been argued that because the cost of transporting energy as a liquid or gaseous fuel is lower than the cost of transmitting energy as electricity it would be more effective to transmit and distribute energy from nuclear fuel in the form of a chemical fuel such as hydrogen. This argument has been critized by Hampson et al., (EAPA 1: 2200) who calculate that the reduced costs of transmission only outweigh the costs of production over distances so large that there appears no realistic application. These calculations neglect the time variation of electricity supply which is fundamental to the planning of an electricity supply system; they also do not appear to do justice to the relationship between the costs of hydrogen and electricity production in an integrated system. These points are included in the analysis presented here by means of the observation that hydrogen generated by nuclear plants with high capital cost and low running cost will be burned by the supply system itself in low-capital-cost plants, suitable for chemical fuels, in order to meet peak demands on the system. This establishes a relationship between the long-run marginal costs of electricity at various times of the day and the long-run marginal cost of hydrogen. These costs are then used to show that, in certain favorable, but common, circumstances, electrolytic hydrogen is the lower-cost source of energy. (from Introduction)

A New Approach of Modeling an Ultra-Super-Critical Power Plant for Performance Improvement

Directory of Open Access Journals (Sweden)

Guolian Hou

2016-04-01

Full Text Available A suitable model of coordinated control system (CCS with high accuracy and simple structure is essential for the design of advanced controllers which can improve the efficiency of the ultra-super-critical (USC power plant. Therefore, with the demand of plant performance improvement, an improved T-S fuzzy model identification approach is proposed in this paper. Firstly, the improved entropy cluster algorithm is applied to identify the premise parameters which can automatically determine the cluster numbers and initial cluster centers by introducing the concept of a decision-making constant and threshold. Then, the learning algorithm is used to modify the initial cluster center and a new structure of concluding part is discussed, the incremental data around the cluster center is used to identify the local linear model through a weighted recursive least-square algorithm. Finally, the proposed approach is employed to model the CCS of a 1000 MW USC one-through boiler power plant by using on-site measured data. Simulation results show that the T-S fuzzy model built in this paper is accurate enough to reflect the dynamic performance of CCS and can be treated as a foundation model for the overall optimizing control of the USC power plant.

Solar Flare Super-Events: When they Can Occur and the Energy Limits of their Realization

Science.gov (United States)

Ishkov, Vitaly N.

2015-03-01

For the successful development of terrestrial civilization it is necessary to estimate the space factors, including phenomena on Sun, which can ruin it or cause such catastrophic loss, that the restoration to the initial level can take unacceptably long time. Super-powerful solar flares are the only such phenomena. Therefore an attempt is undertaken to estimate the possibility of such super-event occurrence at this stage of our star evolution. Since solar flare events are the consequence of the newly emerging magnetic fluxes interacting with the already existing magnetic fields of active regions, are investigated the observed cases which lead to the realization of such super-events. From the observations of the maximal magnetic fluxes during the period of reliable solar observations, the conclusion is made that the super- extreme solar flares cannot significantly exceed the most powerful solar flares which have already been observed. On the statistics of the reliable solar cycles the sunspot groups, in which occurred the most powerful solar super-events (August- September 1859 - solar cycle 10; June 1991 - SC 22; October-November 2003 - SC 23) appeared in the periods of the solar magnetic field reorganization between the epochs of "increased" and "lowered" solar activity.

Hydrogen Production System with High Temperature Electrolysis for Nuclear Power Plant

International Nuclear Information System (INIS)

Kentaro, Matsunaga; Eiji, Hoashi; Seiji, Fujiwara; Masato, Yoshino; Taka, Ogawa; Shigeo, Kasai

2006-01-01

Steam electrolysis with solid oxide cells is one of the most promising methods for hydrogen production, which has the potential to be high efficiency. Its most parts consist of environmentally sound and common materials. Recent development of ceramics with high ionic conductivity suggests the possibility of widening the range of operating temperature with maintaining the high efficiency. Toshiba is constructing a hydrogen production system with solid oxide electrolysis cells for nuclear power plants. Tubular-type cells using YSZ (Yttria-Stabilized- Zirconia) as electrolyte showed good performance of steam electrolysis at 800 to 900 deg C. Larger electrolysis cells with present configuration are to be combined with High Temperature Reactors. The hydrogen production efficiency on the present designed system is expected around 50% at 800 to 900 deg C of operating temperature. For the Fast Reactors, 'advanced cell' with higher efficiency at lower temperature are to be introduced. (authors)

Prediction of hydrogen concentration in nuclear power plant containment under severe accidents using cascaded fuzzy neural networks

Energy Technology Data Exchange (ETDEWEB)

Choi, Geon Pil; Kim, Dong Yeong; Yoo, Kwae Hwan; Na, Man Gyun, E-mail: magyna@chosun.ac.kr

2016-04-15

Highlights: • We present a hydrogen-concentration prediction method in an NPP containment. • The cascaded fuzzy neural network (CFNN) is used in this prediction model. • The CFNN model is much better than the existing FNN model. • This prediction can help prevent severe accidents in NPP due to hydrogen explosion. - Abstract: Recently, severe accidents in nuclear power plants (NPPs) have attracted worldwide interest since the Fukushima accident. If the hydrogen concentration in an NPP containment is increased above 4% in atmospheric pressure, hydrogen combustion will likely occur. Therefore, the hydrogen concentration must be kept below 4%. This study presents the prediction of hydrogen concentration using cascaded fuzzy neural network (CFNN). The CFNN model repeatedly applies FNN modules that are serially connected. The CFNN model was developed using data on severe accidents in NPPs. The data were obtained by numerically simulating the accident scenarios using the MAAP4 code for optimized power reactor 1000 (OPR1000) because real severe accident data cannot be obtained from actual NPP accidents. The root-mean-square error level predicted by the CFNN model is below approximately 5%. It was confirmed that the CFNN model could accurately predict the hydrogen concentration in the containment. If NPP operators can predict the hydrogen concentration in the containment using the CFNN model, this prediction can assist them in preventing a hydrogen explosion.

Hydrogen-oxygen powered internal combustion engine

Science.gov (United States)

Cameron, H.; Morgan, N.

1970-01-01

Hydrogen at 300 psi and oxygen at 800 psi are injected sequentially into the combustion chamber to form hydrogen-rich mixture. This mode of injection eliminates difficulties of preignition, detonation, etc., encountered with carburated, spark-ignited, hydrogen-air mixtures. Ignition at startup is by means of a palladium catalyst.

The hydrogen issue.

Science.gov (United States)

Armaroli, Nicola; Balzani, Vincenzo

2011-01-17

Hydrogen is often proposed as the fuel of the future, but the transformation from the present fossil fuel economy to a hydrogen economy will need the solution of numerous complex scientific and technological issues, which will require several decades to be accomplished. Hydrogen is not an alternative fuel, but an energy carrier that has to be produced by using energy, starting from hydrogen-rich compounds. Production from gasoline or natural gas does not offer any advantage over the direct use of such fuels. Production from coal by gasification techniques with capture and sequestration of CO₂ could be an interim solution. Water splitting by artificial photosynthesis, photobiological methods based on algae, and high temperatures obtained by nuclear or concentrated solar power plants are promising approaches, but still far from practical applications. In the next decades, the development of the hydrogen economy will most likely rely on water electrolysis by using enormous amounts of electric power, which in its turn has to be generated. Producing electricity by burning fossil fuels, of course, cannot be a rational solution. Hydroelectric power can give but a very modest contribution. Therefore, it will be necessary to generate large amounts of electric power by nuclear energy of by renewable energies. A hydrogen economy based on nuclear electricity would imply the construction of thousands of fission reactors, thereby magnifying all the problems related to the use of nuclear energy (e.g., safe disposal of radioactive waste, nuclear proliferation, plant decommissioning, uranium shortage). In principle, wind, photovoltaic, and concentrated solar power have the potential to produce enormous amounts of electric power, but, except for wind, such technologies are too underdeveloped and expensive to tackle such a big task in a short period of time. A full development of a hydrogen economy needs also improvement in hydrogen storage, transportation and distribution

Modeling of hydrogen behaviour in a PWR nuclear power plant containment with the CONTAIN code

International Nuclear Information System (INIS)

Bobovnik, G.; Kljenak, I.

2001-01-01

Hydrogen behavior in the containment during a severe accident in a two-loop Westinghouse-type PWR nuclear power plant was simulated with the CONTAIN code. The accident was initiated with a cold-leg break of the reactor coolant system in a steam generator compartment. In the input model, the containment is represented with 34 cells. Beside hydrogen concentration, the containment atmosphere temperature and pressure and the carbon monoxide concentration were observed as well. Simulations were carried out for two different scenarios: with and without successful actuation of the containment spray system. The highest hydrogen concentration occurs in the containment dome and near the hydrogen release location in the early stages of the accident. Containment sprays do not have a significant effect on hydrogen stratification.(author)

Performance study of a hydrogen powered metal hydride actuator

International Nuclear Information System (INIS)

Bhuiya, Md Mainul Hossain; Kim, Kwang J

2016-01-01

A thermally driven hydrogen powered actuator integrating metal hydride hydrogen storage reactor, which is compact, noiseless, and able to generate smooth actuation, is presented in this article. To test the plausibility of a thermally driven actuator, a conventional piston type actuator was integrated with LaNi 5 based hydrogen storage system. Copper encapsulation followed by compaction of particles into pellets, were adopted to improve overall thermal conductivity of the reactor. The operation of the actuator was thoroughly investigated for an array of operating temperature ranges. Temperature swing of the hydride reactor triggering smooth and noiseless actuation over several operating temperature ranges were monitored for quantification of actuator efficiency. Overall, the actuator generated smooth and consistent strokes during repeated cycles of operation. The efficiency of the actuator was found to be as high as 13.36% for operating a temperature range of 20 °C–50 °C. Stress–strain characteristics, actuation hysteresis etc were studied experimentally. Comparison of stress–strain characteristics of the proposed actuator with traditional actuators, artificial muscles and so on was made. The study suggests that design modification and use of high pressure hydride may enhance the performance and broaden the application horizon of the proposed actuator in future. (paper)

Transportation cost of nuclear off-peak power for hydrogen production based on water electrolysis

International Nuclear Information System (INIS)

Shimizu, Saburo; Ueno, Shuichi

2004-01-01

The paper describes transportation cost of the nuclear off-peak power for a hydrogen production based on water electrolysis in Japan. The power could be obtainable by substituting hydropower and/or fossil fueled power supplying peak and middle demands with nuclear power. The transportation cost of the off-peak power was evaluated to be 1.42 yen/kWh when an electrolyser receives the off-peak power from a 6kV distribution wire. Marked reduction of the cost was caused by the increase of the capacity factor. (author)

Super-Calogero-Moser-Sutherland systems and free super-oscillators: a mapping

International Nuclear Information System (INIS)

Ghosh, Pijush K.

2001-01-01

We show that the supersymmetric rational Calogero-Moser-Sutherland (CMS) model of A N+1 -type is equivalent to a set of free super-oscillators, through a similarity transformation. We prescribe methods to construct the complete eigenspectrum and the associated eigenfunctions, both in supersymmetry-preserving as well as supersymmetry-breaking phases, from the free super-oscillator basis. Further we show that a wide class of super-Hamiltonians realizing dynamical OSp(2 vertical bar 2) supersymmetry, which also includes all types of rational super-CMS as a small subset, are equivalent to free super-oscillators. We study BC N+1 -type super-CMS model in some detail to understand the subtleties involved in this method

Super Riemann surfaces

International Nuclear Information System (INIS)

Rogers, Alice

1990-01-01

A super Riemann surface is a particular kind of (1,1)-dimensional complex analytic supermanifold. From the point of view of super-manifold theory, super Riemann surfaces are interesting because they furnish the simplest examples of what have become known as non-split supermanifolds, that is, supermanifolds where the odd and even parts are genuinely intertwined, as opposed to split supermanifolds which are essentially the exterior bundles of a vector bundle over a conventional manifold. However undoubtedly the main motivation for the study of super Riemann surfaces has been their relevance to the Polyakov quantisation of the spinning string. Some of the papers on super Riemann surfaces are reviewed. Although recent work has shown all super Riemann surfaces are algebraic, some areas of difficulty remain. (author)

Exploration of the Super H-mode regime on DIII-D and potential advantages for burning plasma devices

Energy Technology Data Exchange (ETDEWEB)

Solomon, W. M., E-mail: solomon@fusion.gat.com; Bortolon, A.; Grierson, B. A.; Nazikian, R.; Poli, F. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Snyder, P. B.; Burrell, K. H.; Garofalo, A. M.; Groebner, R. J.; Leonard, A. W.; Meneghini, O.; Osborne, T. H.; Petty, C. C. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Loarte, A. [ITER Organization, Route de Vinon-sur-Verdon - CS 90 046, 13067 St Paul Lez Durance Cedex (France)

2016-05-15

A new high pedestal regime (“Super H-mode”) has been predicted and accessed on DIII-D. Super H-mode was first achieved on DIII-D using a quiescent H-mode edge, enabling a smooth trajectory through pedestal parameter space. By exploiting Super H-mode, it has been possible to access high pedestal pressures at high normalized densities. While elimination of Edge localized modes (ELMs) is beneficial for Super H-mode, it may not be a requirement, as recent experiments have maintained high pedestals with ELMs triggered by lithium granule injection. Simulations using TGLF for core transport and the EPED model for the pedestal find that ITER can benefit from the improved performance associated with Super H-mode, with increased values of fusion power and gain possible. Similar studies demonstrate that the Super H-mode pedestal can be advantageous for a steady-state power plant, by providing a path to increasing the bootstrap current while simultaneously reducing the demands on the core physics performance.

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

International Nuclear Information System (INIS)

Suhaib Muhammad Ali; John Andrews

2006-01-01

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

BREEDING SUPER-EARTHS AND BIRTHING SUPER-PUFFS IN TRANSITIONAL DISKS

Energy Technology Data Exchange (ETDEWEB)

Lee, Eve J.; Chiang, Eugene, E-mail: evelee@berkeley.edu, E-mail: echiang@astro.berkeley.edu [Department of Astronomy, University of California Berkeley, Berkeley, CA 94720-3411 (United States)

2016-02-01

The riddle posed by super-Earths (1–4R{sub ⊕}, 2–20M{sub ⊕}) is that they are not Jupiters: their core masses are large enough to trigger runaway gas accretion, yet somehow super-Earths accreted atmospheres that weigh only a few percent of their total mass. We show that this puzzle is solved if super-Earths formed late, as the last vestiges of their parent gas disks were about to clear. This scenario would seem to present fine-tuning problems, but we show that there are none. Ambient gas densities can span many (in one case up to 9) orders of magnitude, and super-Earths can still robustly emerge after ∼0.1–1 Myr with percent-by-weight atmospheres. Super-Earth cores are naturally bred in gas-poor environments where gas dynamical friction has weakened sufficiently to allow constituent protocores to gravitationally stir one another and merge. So little gas is present at the time of core assembly that cores hardly migrate by disk torques: formation of super-Earths can be in situ. The basic picture—that close-in super-Earths form in a gas-poor (but not gas-empty) inner disk, fed continuously by gas that bleeds inward from a more massive outer disk—recalls the largely evacuated but still accreting inner cavities of transitional protoplanetary disks. We also address the inverse problem presented by super-puffs: an uncommon class of short-period planets seemingly too voluminous for their small masses (4–10R{sub ⊕}, 2–6M{sub ⊕}). Super-puffs most easily acquire their thick atmospheres as dust-free, rapidly cooling worlds outside ∼1 AU where nebular gas is colder, less dense, and therefore less opaque. Unlike super-Earths, which can form in situ, super-puffs probably migrated in to their current orbits; they are expected to form the outer links of mean-motion resonant chains, and to exhibit greater water content. We close by confronting observations and itemizing remaining questions.

BREEDING SUPER-EARTHS AND BIRTHING SUPER-PUFFS IN TRANSITIONAL DISKS

International Nuclear Information System (INIS)

Lee, Eve J.; Chiang, Eugene

2016-01-01

The riddle posed by super-Earths (1–4R ⊕ , 2–20M ⊕ ) is that they are not Jupiters: their core masses are large enough to trigger runaway gas accretion, yet somehow super-Earths accreted atmospheres that weigh only a few percent of their total mass. We show that this puzzle is solved if super-Earths formed late, as the last vestiges of their parent gas disks were about to clear. This scenario would seem to present fine-tuning problems, but we show that there are none. Ambient gas densities can span many (in one case up to 9) orders of magnitude, and super-Earths can still robustly emerge after ∼0.1–1 Myr with percent-by-weight atmospheres. Super-Earth cores are naturally bred in gas-poor environments where gas dynamical friction has weakened sufficiently to allow constituent protocores to gravitationally stir one another and merge. So little gas is present at the time of core assembly that cores hardly migrate by disk torques: formation of super-Earths can be in situ. The basic picture—that close-in super-Earths form in a gas-poor (but not gas-empty) inner disk, fed continuously by gas that bleeds inward from a more massive outer disk—recalls the largely evacuated but still accreting inner cavities of transitional protoplanetary disks. We also address the inverse problem presented by super-puffs: an uncommon class of short-period planets seemingly too voluminous for their small masses (4–10R ⊕ , 2–6M ⊕ ). Super-puffs most easily acquire their thick atmospheres as dust-free, rapidly cooling worlds outside ∼1 AU where nebular gas is colder, less dense, and therefore less opaque. Unlike super-Earths, which can form in situ, super-puffs probably migrated in to their current orbits; they are expected to form the outer links of mean-motion resonant chains, and to exhibit greater water content. We close by confronting observations and itemizing remaining questions

The Super Patalan Numbers

OpenAIRE

Richardson, Thomas M.

2014-01-01

We introduce the super Patalan numbers, a generalization of the super Catalan numbers in the sense of Gessel, and prove a number of properties analagous to those of the super Catalan numbers. The super Patalan numbers generalize the super Catalan numbers similarly to how the Patalan numbers generalize the Catalan numbers.

Grassmann, super-Kac-Moody and super-derivation algebras

International Nuclear Information System (INIS)

Frappat, L.; Ragoucy, E.; Sorba, P.

1989-05-01

We study the cyclic cocycles of degree one on the Grassmann algebra and on the super-circle with N supersymmetries (i.e. the tensor product of the algebra of functions on the circle times a Grassmann algebra with N generators). They are related to central extensions of graded loop algebras (i.e. super-Kac-Moody algebras). The corresponding algebras of super-derivations have to be compatible with the cocycle characterizing the extension; we give a general method for determining these algebras and examine in particular the cases N = 1,2,3. We also discuss their relations with the Ademollo et al. algebras, and examine the possibility of defining new kinds of super-conformal algebras, which, for N > 1, generalize the N = 1 Ramond-Neveu-Schwarz algebra

Hydrogen production at hydro-power plants

Science.gov (United States)

Tarnay, D. S.

A tentative design for hydrogen-producing installations at hydropower facilities is discussed from technological, economic and applications viewpoints. The plants would use alternating current to electrolyze purified river water. The hydrogen would be stored in gas or liquid form and oxygen would be sold or vented to the atmosphere. The hydrogen could later be burned in a turbine generator for meeting peak loads, either in closed or open cycle systems. The concept would allow large hydroelectric plants to function in both base- and peak-load modes, thus increasing the hydraulic utilization of the plant and the capacity factor to a projected 0.90. Electrolyzer efficiencies ranging from 0.85-0.90 have been demonstrated. Excess hydrogen can be sold for other purposes or, eventually, as domestic and industrial fuel, at prices competitive with current industrial hydrogen.

Improved estimates of separation distances to prevent unacceptable damage to nuclear power plant structures from hydrogen detonation for gaseous hydrogen storage. Technical report

International Nuclear Information System (INIS)

1994-05-01

This report provides new estimates of separation distances for nuclear power plant gaseous hydrogen storage facilities. Unacceptable damage to plant structures from hydrogen detonations will be prevented by having hydrogen storage facilities meet separation distance criteria recommended in this report. The revised standoff distances are based on improved calculations on hydrogen gas cloud detonations and structural analysis of reinforced concrete structures. Also, the results presented in this study do not depend upon equivalencing a hydrogen detonation to an equivalent TNT detonation. The static and stagnation pressures, wave velocity, and the shock wave impulse delivered to wall surfaces were computed for several different size hydrogen explosions. Separation distance equations were developed and were used to compute the minimum separation distance for six different wall cases and for seven detonating volumes (from 1.59 to 79.67 lbm of hydrogen). These improved calculation results were compared to previous calculations. The ratio between the separation distance predicted in this report versus that predicted for hydrogen detonation in previous calculations varies from 0 to approximately 4. Thus, the separation distances results from the previous calculations can be either overconservative or unconservative depending upon the set of hydrogen detonation parameters that are used. Consequently, it is concluded that the hydrogen-to-TNT detonation equivalency utilized in previous calculations should no longer be used

Evaluation of Hybrid Power Plants using Biomass, Photovoltaics and Steam Electrolysis for Hydrogen and Power Generation

Science.gov (United States)

Petrakopoulou, F.; Sanz, J.

2014-12-01

Steam electrolysis is a promising process of large-scale centralized hydrogen production, while it is also considered an excellent option for the efficient use of renewable solar and geothermal energy resources. This work studies the operation of an intermediate temperature steam electrolyzer (ITSE) and its incorporation into hybrid power plants that include biomass combustion and photovoltaic panels (PV). The plants generate both electricity and hydrogen. The reference -biomass- power plant and four variations of a hybrid biomass-PV incorporating the reference biomass plant and the ITSE are simulated and evaluated using exergetic analysis. The variations of the hybrid power plants are associated with (1) the air recirculation from the electrolyzer to the biomass power plant, (2) the elimination of the sweep gas of the electrolyzer, (3) the replacement of two electric heaters with gas/gas heat exchangers, and (4) the replacement two heat exchangers of the reference electrolyzer unit with one heat exchanger that uses steam from the biomass power plant. In all cases, 60% of the electricity required in the electrolyzer is covered by the biomass plant and 40% by the photovoltaic panels. When comparing the hybrid plants with the reference biomass power plant that has identical operation and structure as that incorporated in the hybrid plants, we observe an efficiency decrease that varies depending on the scenario. The efficiency decrease stems mainly from the low effectiveness of the photovoltaic panels (14.4%). When comparing the hybrid scenarios, we see that the elimination of the sweep gas decreases the power consumption due to the elimination of the compressor used to cover the pressure losses of the filter, the heat exchangers and the electrolyzer. Nevertheless, if the sweep gas is used to preheat the air entering the boiler of the biomass power plant, the efficiency of the plant increases. When replacing the electric heaters with gas-gas heat exchangers, the

Study of hydrogen isotopes super permeation through vanadium membrane on 'Prometheus' setup

International Nuclear Information System (INIS)

Musyaev, R. K.; Yukhimchuk, A. A.; Lebedev, B. S.; Busnyuk, A. O.; Notkin, M. E.; Samartsev, A. A.; Livshits, A. I.

2008-01-01

To develop the membrane pumping technology by means of superpermeable membranes at RFNC-VNIIEF in the 'Prometheus' setup, the experiments on superpermeation of hydrogen isotopes through metal membranes were carried out. The experimental results on superpermeation of thermal atoms of hydrogen isotopes including tritium through a cylindrical vanadium membrane are presented. The possibility of effective pumping, compression and recuperation of hydrogen isotopes by means of superpermeable membrane was demonstrated. The evaluation of membrane pumping rates and asymmetry degree of pure vanadium membrane was given. The work was performed under the ISTC-2854 project. (authors)

Pioneering SUPER - Small Unit Passively-safe Enclosed Reactor - 15559

International Nuclear Information System (INIS)

Bhownik, P.K.; Gairola, A.; Shamim, J.A.; Suh, K.Y.; Suh, K.S.

2015-01-01

This paper presents the basic features of the Small Unit Passively-safe Enclosed Reactor abbreviated as SUPER, a new reactor system that has been designed and proposed at the Seoul National University's Department of Energy Systems Engineering. SUPER is a small modular reactor system or SMR that is cooled by sub-cooled as well as supercritical water. As a new member of SMRs, SUPER is a small-scale nuclear plant that is designed to be factory-manufactured and shipped as modules to be assembled at a site. The concept offers promising answers to many questions about nuclear power including proliferation resistance, waste management, safety, and startup costs. SUPER is a customized paradigm of a supercritical water reactor or SCWR, a type sharing commonalities with the current fleet of light water reactors, or LWRs. SUPER has evolved from the System-integrated Modular Advance Reactor, or SMART, being developed at the Korea Atomic Energy Research Institute, or KAERI. SUPER enhanced the safety features for robustness, design/equipment simplification for natural convection, multi-purpose application for co-generation flexibilities, suitable for isolated or small electrical grids, just-in-time capacity addition, short construction time, and last, but not least, lower capital cost per unit. The primary objectives of SUPER is to develop the conceptual design for a safe and economic small, natural circulation SCWR, to address the economic and safety attributes of the concept, and to demonstrate its technical feasibilities. (authors)

Characteristics of Hydrogen Monitoring Systems for Severe Accident Management at a Nuclear Power Plant

Science.gov (United States)

Petrosyan, V. G.; Yeghoyan, E. A.; Grigoryan, A. D.; Petrosyan, A. P.; Movsisyan, M. R.

2018-02-01

One of the main objectives of severe accident management at a nuclear power plant is to protect the integrity of the containment, for which the most serious threat is possible ignition of the generated hydrogen. There should be a monitoring system providing information support of NPP personnel, ensuring data on the current state of a containment gaseous environment and trends in its composition changes. Monitoring systems' requisite characteristics definition issues are considered by the example of a particular power unit. Major characteristics important for proper information support are discussed. Some features of progression of severe accident scenarios at considered power unit are described and a possible influence of the hydrogen concentration monitoring system performance on the information support reliability in a severe accident is analyzed. The analysis results show that the following technical characteristics of the combustible gas monitoring systems are important for the proper information support of NPP personnel in the event of a severe accident at a nuclear power plant: measured parameters, measuring ranges and errors, update rate, minimum detectable concentration of combustible gas, monitoring reference points, environmental qualification parameters of the system components. For NPP power units with WWER-440/270 (230) type reactors, which have a relatively small containment volume, the update period for measurement results is a critical characteristic of the containment combustible gas monitoring system, and the choice of monitoring reference points should be focused not so much on the definition of places of possible hydrogen pockets but rather on the definition of places of a possible combustible mixture formation. It may be necessary for the above-mentioned power units to include in the emergency operating procedures measures aimed at a timely heat removal reduction from the containment environment if there are signs of a severe accident phase

A rationale for large inertial fusion plants producing hydrogen for powering low emission vehicles

International Nuclear Information System (INIS)

Logan, B.G.

1993-01-01

Inertial Fusion Energy (IFE) has been identified in the 1991 National Energy Strategy, along with Magnetic Fusion Energy (MFE), as one of only three inexhaustible energy sources for long term energy supply (past 2025), the other alternatives being fission and solar energy. Fusion plants, using electrolysis, could also produce hydrogen to power low emission vehicles in a potentially huge future US market: > 500 GWe would be needed for example, to replace all foreign oil imports with equal-energy hydrogen, assuming 70%-efficient electrolysis. Any inexhaustible source of electricity, including IFE and MFE reactors, can thus provide a long term renewable source of hydrogen as well as solar, wind and biomass sources. Hydrogen production by both high temperature thermochemical cycles and by electrolysis has been studied for MFE, but avoiding trace tritium contamination of the hydrogen product would best be assured using electrolysis cells well separated from any fusion coolant loops. The motivations to consider IFE or MFE producing renewable hydrogen are: (1) reducing US dependence on foreign oil imports and the associated trade deficient; (2) a hydrogen-based transportation system could greatly mitigate future air pollution and greenhouse gases; (3) investments in hydrogen pipelines, storage, and distribution systems could be used for a variety of hydrogen sources; (4) a hydrogen pipeline system could access and buffer sufficiently large markets that temporary outages of large (>> 1 GWe size) fusion hydrogen units could be tolerated

Evaluation of the Super Efficient Refrigerator Program (SERP) in the Bonneville Power Administration service territory

Energy Technology Data Exchange (ETDEWEB)

Lee, A.D.; Conger, R.L.

1996-06-01

The Super Efficient Refrigerator Program (SERP) is a collaborative utility program intended to transform the market for energy-efficient and environmentally friendly refrigerators. it is one of the first examples of large-scale {open_quotes}market transformation{close_quotes} energy efficiency program. This report documents the evaluation of SERP ({open_quotes}the Program{close_quotes}) in the Bonneville Power Administration`s (Bonneville`s) service territory. Pacific Northwest National Laboratory (PNNL) conducted this evaluation for Bonneville. This study includes the process evaluation, preliminary impact evaluation, and market transformation assessment. It is based on site visits and interviews with refrigerator dealers and manufacturers, industry data, and Bonneville information. Results from this study are compared with those from a parallel study that examines the Program across the 24 participating utilities.

Medium power hydrogen arcjet performance

Science.gov (United States)

Curran, Francis M.; Bullock, S. R.; Haag, Thomas W.; Sarmiento, Charles J.; Sankovic, John M.

1991-01-01

An experimental investigation was performed to evaluate hydrogen arcjet operating characteristics in the range of 1 to 4 kW. A series of nozzles were operated in modular laboratory thrusters to examine the effects of geometric parameters such as constrictor diameter and nozzle divergence angle. Each nozzle was tested over a range of current and mass flow rates to explore stability and performance. In the range of mass flow rates and power levels tested, specific impulse values between 650 and 1250 sec were obtained at efficiencies between 30 and 40 percent. The performance of the two larger half angle (20, 15 deg) nozzles was similar for each of the two constrictor diameters tested. The nozzles with the smallest half angle (10 deg) were difficult to operate. A restrike mode of operation was identified and described. Damage in the form of melting was observed in the constrictor region of all the nozzle inserts tested. Arcjet ignition was also difficult in many tests and a glow discharge mode that prevents starting was identified.

Production of Jet Fuel-Range Hydrocarbons from Hydrodeoxygenation of Lignin over Super Lewis Acid Combined with Metal Catalysts.

Science.gov (United States)

Wang, Hongliang; Wang, Huamin; Kuhn, Eric; Tucker, Melvin P; Yang, Bin

2018-01-10

Super Lewis acids containing the triflate anion [e.g., Hf(OTf) 4 , Ln(OTf) 3 , In(OTf) 3 , Al(OTf) 3 ] and noble metal catalysts (e.g., Ru/C, Ru/Al 2 O 3 ) formed efficient catalytic systems to generate saturated hydrocarbons from lignin in high yields. In such catalytic systems, the metal triflates mediated rapid ether bond cleavage through selective bonding to etheric oxygens while the noble metal catalyzed subsequent hydrodeoxygenation (HDO) reactions. Near theoretical yields of hydrocarbons were produced from lignin model compounds by the combined catalysis of Hf(OTf) 4 and ruthenium-based catalysts. When a technical lignin derived from a pilot-scale biorefinery was used, more than 30 wt % of the hydrocarbons produced with this catalytic system were cyclohexane and alkylcyclohexanes in the jet fuel range. Super Lewis acids are postulated to strongly interact with lignin substrates by protonating hydroxyl groups and ether linkages, forming intermediate species that enhance hydrogenation catalysis by supported noble metal catalysts. Meanwhile, the hydrogenation of aromatic rings by the noble metal catalysts can promote deoxygenation reactions catalyzed by super Lewis acids. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Thermo-economic analysis of integrated membrane-SMR ITM-oxy-combustion hydrogen and power production plant

International Nuclear Information System (INIS)

Sanusi, Yinka S.; Mokheimer, Esmail M.A.; Habib, Mohamed A.

2017-01-01

Highlights: •A methane reforming reactor integrated to an oxy-combustion plant is proposed. •Co-production of power and hydrogen was investigated and presented. •Optimal thermo-economic operating conditions of the system were identified and presented. •The ion transport membrane oxygen separation unit has the highest capital cost. •The combustor has the highest exergy destruction. -- Abstract: The demand for hydrogen has greatly increased in the last decade due to the stringent regulations enacted to address environmental pollution concerns. Natural gas reforming is currently the most mature technology for large-scale hydrogen production. However, it is usually associated with greenhouse gas emissions. As part of the strategies to reduce greenhouse gas emissions, new designs need to be developed to integrate hydrogen production facilities that are based on natural gas reforming with carbon capture facilities. In this study, we carried out energy, exergy and economic analysis of hydrogen production in a steam methane reforming reactor integrated with an oxy-combustion plant for co-production of power and hydrogen. The results show that the overall system efficiency and hydrogen production efficiency monotonically increase with increasing the combustor exit temperature (CET), increasing the amount of hydrogen extracted and decreasing the auxiliary fuel added to the system. The optimal thermo-economic operating conditions of the system were obtained as reformer pressure of 15 bar, auxiliary fuel factor of 0.8 and hydrogen extraction factor of 0.6. The production cost of hydrogen using the proposed system, under these optimal operating conditions, is within the range suggested by the International Energy Agency (IEA). Further analysis shows that the capital cost of the membrane-air separation unit (ITM) has the major share in the total investment cost of the system and constitutes 37% of the total capital cost of the system at the CET of 1500 K. The exergy

Solid-immersion fluorescence microscopy with increased emission and super resolution

Energy Technology Data Exchange (ETDEWEB)

Liau, Z. L.; Porter, J. M. [Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02420 (United States); Liau, A. A.; Chen, J. J. [Institute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Salmon, W. C. [Whitehead Institute, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Sheu, S. S. [Department of Medicine, Jefferson Medical College, Philadelphia, Pennsylvania 19107 (United States)

2015-01-07

We investigate solid-immersion fluorescence microscopy suitable for super-resolution nanotechnology and biological imaging, and have observed limit of resolution as small as 15 nm with microspheres, mitochondria, and chromatin fibers. We have further observed that fluorescence efficiency increases with excitation power density, implicating appreciable stimulated emission and increased resolution. We discuss potential advantages of the solid-immersion microscopy, including combined use with previously established super-resolution techniques for reaching deeper beyond the conventional diffraction limit.

Hydrogen gains further momentum

International Nuclear Information System (INIS)

Anon.

2017-01-01

As first industrial production projects should become a reality in the next few years, hydrogen as a source of energy will find important applications with mobility, which momentum is rapid and irresistible. Next steps will be the (large capacity) storage of hydrogen associated to power-to-gas systems and the generalization of renewable energies. This document presents 5 articles, which themes are: Description and explanation of the process of hydrogen production; Presentation of the H2V project for the construction, in Normandy, of the first operational industrial hydrogen production plant using electric power 100 pc generated by renewable energies; The conversion of electric power from renewable energies through hydrogen storage and fuel cells for buildings applications (Sylfen project); The development of a reversible fuel cell at Mines-Paris Tech University, that will be adapted to the storage of renewable electric power; Hydrogen as a lever for the development of zero-emission vehicles, from trucks to cars and bicycles

HNEI wind-hydrogen program

International Nuclear Information System (INIS)

Neill, D.; Holst, B.; Yu, C.; Huang, N.; Wei, J.

1990-01-01

This paper reports on wind powered hydrogen production which is promising for Hawaii because Hawaii's wind energy potential exceeds the state's current electrical energy requirements by more than twenty-fold. Wind energy costs are now approaching $0.06 to $0.08/kWh, and the U.S. Department of Energy has set a goal of $0.04/kWh. These conditions make wind power a good source for electrolytic production of hydrogen. HNEI's wind-hydrogen program, at the HNEI-Kahua Wind Energy Storage Test facility on the island of Hawaii, is developing energy storage and power electronic systems for intermittent wind and solar devices to provide firm power to the utility or to a stand-alone hybrid system. In mid 1990, the first wind-hydrogen production/storage/ generation system is scheduled for installation. HNEI's wind- hydrogen program will provide research, development, demonstration, and education on the great potential and benefits of hydrogen

Failure investigation of a secondary super heater tube in a 140 MW thermal power plant

Directory of Open Access Journals (Sweden)

Atanu Saha

2017-04-01

Full Text Available This article describes the findings of a detailed investigation into the failure of a secondary super heater tube in a 140 MW thermal power plant. Preliminary macroscopic examinations along with visual examination, dimensional measurement and chemical analysis were carried out to deduce the probable cause of failure. In addition optical microscopy was a necessary supplement to understand the cause of failure. It was concluded that the tube had failed due to severe creep damage caused by high metal temperature during service. The probable causes of high metal temperature may be in sufficient flow of steam due to partial blockage, presence of thick oxide scale on ID surface, high flue gas temperature etc. rupture.

Research and development of super light water reactors and super fast reactors in Japan

International Nuclear Information System (INIS)

Oka, Y.; Morooka, S.; Yamakawa, M.; Ishiwatari, Y.; Ikejiri, S.; Katsumura, Y.; Muroya, Y.; Terai, T.; Sasaki, K.; Mori, H.; Hamamoto, Y.; Okumura, K.; Kugo, T.; Nakatsuka, T.; Ezato, K.; Akasaka, N.; Hotta, A.

2011-01-01

Super Light Water Reactors (Super LWR) and Super Fast Reactors (Super FR) are the supercritical- pressure light water cooled reactors (SCWR) that are developed by the research group of University of Tokyo since 1989 and now jointly under development with the researchers of Waseda University, University of Tokyo and other organizations in Japan. The principle of the reactor concept development, the results of the past Super LWR and Super FR R&D as well as the R&D program of the Super FR second phase project are described. (author)

The super W∞ symmetry of the Manin-Radul super KP hierarchy

International Nuclear Information System (INIS)

Das, A.; Sin, S.J.

1991-11-01

We show that the Manin-Radul super KP hierarchy is invariant under super W ∞ transformations. These transformations are characterized by time dependent flows which commute with the usual flows generated by the conserved quantities of the super KP hierarchy. (author). 16 refs

Modeling a constant power load for nickel-hydrogen battery testing using SPICE

Science.gov (United States)

Bearden, Douglas B.; Lollar, Louis F.; Nelms, R. M.

1990-01-01

The effort to design and model a constant power load for the HST (Hubble Space Telescope) nickel-hydrogen battery tests is described. The constant power load was designed for three different simulations on the batteries: life cycling, reconditioning, and capacity testing. A dc-dc boost converter was designed to act as this constant power load. A boost converter design was chosen because of the low test battery voltage (4 to 6 VDC) generated and the relatively high power requirement of 60 to 70 W. The SPICE model was shown to consistently predict variations in the actual circuit as various designs were attempted. It is concluded that the confidence established in the SPICE model of the constant power load ensures its extensive utilization in future efforts to improve performance in the actual load circuit.

Gamma-ray spectrum of the radiaoctive dust produced by the super-hydrogen bomb test explosion on March 1, 1954

Energy Technology Data Exchange (ETDEWEB)

Shimizu, S.

1987-03-15

The super-hydrogen bomb test explosion, the so-called Bravo test of a fission-fusion-fission bomb, was carried out on Bikini Atoll in the mid-Pacific on March 1, 1954. Twenty-three Japanese fishermen on board a fishing boat about 90 miles north-east of the test site were attacked unexpectedly by the fallout, radioactive fine debris of coral reef. Within several months after the accident by radiochemical analysis about 20 different nuclides of fission products and, in addition, a considerable amount of /sup 235/U were discovered from the fallout. As we have been preserving a minute amount of the original fallout dust collected on board the fishing boat 31 years ago, measurements of ..gamma.. rays from it have recently been used to find some active nuclides, if still existing. In the ..gamma..-ray spectrum observed there exist evident peaks of ..gamma.. and X-rays from /sup 241/Am, /sup 155/Eu, /sup 137/Cs and /sup 60/Co. Absolute intensities of these four nuclides, still remaining 31 years after the explosion of the bomb, have been estimated. Some discussion on our finding is presented.

Concept for the analysis of hydrogen problems in nuclear power plants after accidents

International Nuclear Information System (INIS)

PreuBer, G.; Freudenstein, K.F.; Reinders, R.

1997-01-01

After accidents in nuclear power plants, which lead to a overheating of the core up to a partial or complete core melting, hydrogen is produced due to the reaction of fuel cladding and other metallic structures of the core with the cooling water. This hydrogen enters the containment through a leak of the primary system or at reactor pressure vessel failure. The danger of fast deflagration or explosions appears which may affect the containment. For the analysis of the containment phenomena two different types of computer codes are used, lumped parameter codes and 3D codes. This paper describes the advantages and the limitations of both methods. The codes used by Siemens KWU are presented with some examples for hydrogen analyses. A prospect of further development is given. (author)

Research and development of a super fast reactor (12). Considerations for the reactor characteristics

International Nuclear Information System (INIS)

Goto, Shoji; Ishiwatari, Yuki; Oka, Yoshiaki

2008-01-01

A research program aimed at developing the Super Fast Reactor (Super FR) has been entrusted by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan since December 2005. It includes the following three projects. (A) Development of the Super Fast Reactor concept. (B)Thermal-hydraulic experiments. (C) Materials development. Tokyo Electric Power Company (TEPCO) has joined this program and works on part (A) together with the University of Tokyo. From the utility's viewpoint, it is important to consider the most desirable characteristics for Super FR to have. Four issues were identified in project (A), (1) Fuel design, (2) Reactor core design, (3) Safety, and (4) Plant characteristics of Super FR. This report describes the desired characteristics of Super FR with respect to item (1) fuel design and item (2) Reactor core design, as compared with a boiling water reactor (BWR) plant. The other two issues will be discussed in this project, and will also be considered in the design process of Super FR. (author)

Performance of electric forklift with low-temperature polymer exchange membrane fuel cell power module and metal hydride hydrogen storage extension tank

Science.gov (United States)

Lototskyy, Mykhaylo V.; Tolj, Ivan; Parsons, Adrian; Smith, Fahmida; Sita, Cordellia; Linkov, Vladimir

2016-06-01

We present test results of a commercial 3-tonne electric forklift (STILL) equipped with a commercial fuel cell power module (Plug Power) and a MH hydrogen storage tank (HySA Systems and TF Design). The tests included: (i) performance evaluation of "hybrid" hydrogen storage system during refuelling at low (fuel cell power module (alone) - power module with integrated MH tank; and (iii) performance tests of the forklift during its operation under working conditions. It was found that (a) the forklift with power module and MH tank can achieve 83% of maximum hydrogen storage capacity during 6 min refuelling (for full capacity 12-15 min); (b) heavy-duty operation of the forklift is characterised by 25% increase in energy consumption, and during system operation more uniform power distribution occurs when operating in the fuel cell powering mode with MH, in comparison to the battery powering mode; (c) use of the fully refuelled fuel cell power module with the MH extension tank allows for uninterrupted operation for 3 h 6 min and 7 h 15 min, for heavy- and light-duty operation, respectively.

Harvesting electrostatic energy using super-hydrophobic surfaces

Science.gov (United States)

Pociecha, Dominik; Zylka, Pawel

2016-11-01

Almost all environments are now being extensively populated by miniaturized, nano-powered electronic sensor devices communicated together through wireless sensor networks building Internet of Things (IoT). Various energy harvesting techniques are being more and more frequently proposed for battery-less powering of such remote, unattended, implantable or wearable sensors or other low-power electronic gadgets. Energy harvesting relays on extracting energy from the ambient sources readily accessible at the sensor location and converting it into electrical power. The paper exploits possibility of generating electric energy safely accessible for nano-power electronics using tribo-electric and electrostatic induction phenomena displayed at super-hydrophobic surfaces impinged by water droplets. Mechanism of such interaction is discussed and illustrated by experimental results.

Ultra-low power hydrogen sensing based on a palladium-coated nanomechanical beam resonator

DEFF Research Database (Denmark)

Henriksson, Jonas; Villanueva Torrijo, Luis Guillermo; Brugger, Juergen

2012-01-01

Hydrogen sensing is essential to ensure safety in near-future zero-emission fuel cell powered vehicles. Here, we present a novel hydrogen sensor based on the resonant frequency change of a nanoelectromechanical clamped-clamped beam. The beam is coated with a Pd layer, which expands in the presence...... of H 2, therefore generating a stress build-up that causes the frequency of the device to drop. The devices are able to detect H2 concentrations below 0.5% within 1 s of the onset of the exposure using only a few hundreds of pW of power, matching the industry requirements for H 2 safety sensors......, whereby the responsivity of the sensors is fully restored and the chemo-mechanical process is accelerated, significantly decreasing response times. The sensors are fabricated using standard processes, facilitating their eventual mass-production. © 2012 The Royal Society of Chemistry....

Signal Characteristics of Super-Resolution Near-Field Structure Disks with 100 GB Capacity

Science.gov (United States)

Kim, Jooho; Hwang, Inoh; Kim, Hyunki; Park, Insik; Tominaga, Junji

2005-05-01

We report the basic characteristics of super resolution near-field structure (Super-RENS) media at a blue laser optical system (laser wavelength 405 nm, numerical aperture 0.85). Using a novel write once read many (WORM) structure for a blue laser system, we obtained a carrier-to-noise ratio (CNR) above 33 dB from the signal of the 37.5 nm mark length, which is equivalent to a 100 GB capacity with a 0.32 micrometer track pitch, and an eye pattern for 50 GB (2T: 75 nm) capacity using a patterned signal. Using a novel super-resolution material (tellurium, Te) with low super-resolution readout power, we also improved the read stability.

Analysis of stress concentration in the Dutton groove regions of the Super Lightweight External Tank

Science.gov (United States)

Ahmed, R.

1995-05-01

Because the 2195 aluminum-lithium material of the super lightweight external tank (SLWT ET) has a lower toughness than the 2219 aluminum used in previous ET's, careful attention must be paid to stress concentrations. This report details the analysis performed on some of the stress concentrations in the orthogrid panels of the liquid hydrogen tank.

Super high-power AlGaInN-based laser diodes with a single broad-area stripe emitter fabricated on a GaN substrate

Energy Technology Data Exchange (ETDEWEB)

Goto, Shu; Ohta, Makoto; Yabuki, Yoshifumi; Hoshina, Yukio; Hashizu, Toshihiro; Ikeda, Masao [Development Center, Sony Shiroishi Semiconductor, Inc., 3-53-2 Shiratori, Shiroishi, Miyagi, 989-0734 (Japan); Naganuma, Kaori; Tamamura, Koshi [Core Technology Development Group, Micro Systems Network Company, Sony Corporation, 4-14-1 Asahi-cho, Atsugi-shi Kanagawa, 243-0041 (Japan)

2003-11-01

AlGaInN-based blue-violet laser diodes with a single broad-area stripe emitter were successfully fabricated on GaN substrates. Three stripe widths were examined; 10, 50, and 100 {mu}m, and the maximum light output power of 0.94 W under cw operation at 20 C was achieved for the sample with a stripe width of 10 {mu}m. A super high-power laser diode array was fabricated using 11 of these high-performance laser chips, with a resultant output power of 6.1 W under cw operation at 20 C. This result represents the highest reported output power for blue-violet laser diodes. (copyright 2003 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Hydrogen energy stations: along the roadside to the hydrogen economy

International Nuclear Information System (INIS)

Clark, W.W.; Rifkin, J.; O'Connor, T.; Swisher, J.; Lipman, T.; Rambach, G.

2005-01-01

Hydrogen has become more than an international topic of discussion within government and among industry. With the public announcements from the European Union and American governments and an Executive Order from the Governor of California, hydrogen has become a ''paradigm change'' targeted toward changing decades of economic and societal behaviours. The public demand for clean and green energy as well as being ''independent'' or not located in political or societal conflict areas, has become paramount. The key issues are the commitment of governments through public policies along with corporations. Above all, secondly, the advancement of hydrogen is regional as it depends upon infrastructure and fuel resources. Hence, the hydrogen economy, to which the hydrogen highway is the main component, will be regional and creative. New jobs, businesses and opportunities are already emerging. And finally, the costs for the hydrogen economy are critical. The debate as to hydrogen being 5 years away from being commercial and available in the marketplace versus needing more research and development contradicts the historical development and deployment of any new technology be it bio-science, flat panel displays, computers or mobile phones. The market drivers are government regulations and standards soon thereafter matched by market forces and mass production. Hydrogen is no different. What this paper does is describes is how the hydrogen highway is the backbone to the hydrogen economy by becoming, with the next five years, both regional and commercial through supplying stationary power to communities. Soon thereafter, within five to ten years, these same hydrogen stations will be serving hundreds and then thousands of hydrogen fuel powered vehicles. Hydrogen is the fuel for distributed energy generation and hence positively impacts the future of public and private power generators. The paradigm has already changed. (author)

Reduction of 4-dim self dual super Yang-Mills onto super Riemann surfaces

International Nuclear Information System (INIS)

Mendoza, A.; Restuccia, A.; Martin, I.

1990-05-01

Recently self dual super Yang-Mills over a super Riemann surface was obtained as the zero set of a moment map on the space of superconnections to the dual of the super Lie algebra of gauge transformations. We present a new formulation of 4-dim Euclidean self dual super Yang-Mills in terms of constraints on the supercurvature. By dimensional reduction we obtain the same set of superconformal field equations which define self dual connections on a super Riemann surface. (author). 10 refs

Comparative assessment of hydrogen storage and international electricity trade for a Danish energy system with wind power and hydrogen/fuel cell technologies. Final project report

Energy Technology Data Exchange (ETDEWEB)

Soerensen, Bent (Roskilde University, Energy, Environment and Climate Group, Dept. of Environmental, Social and Spatial Change (ENSPAC) (DK)); Meibom, P.; Nielsen, Lars Henrik; Karlsson, K. (Technical Univ. of Denmark, Risoe National Laboratory for Sustainable Energy, Systems Analysis Dept., Roskilde (DK)); Hauge Pedersen, A. (DONG Energy, Copenhagen (DK)); Lindboe, H.H.; Bregnebaek, L. (ea Energy Analysis, Copenhagen (DK))

2008-02-15

This report is the final outcome of a project carried out under the Danish Energy Agency's Energy Research Programme. The aims of the project can be summarized as follows: 1) Simulation of an energy system with a large share of wind power and possibly hydrogen, including economic optimization through trade at the Nordic power pool (exchange market) and/or use of hydrogen storage. The time horizon is 50 years. 2) Formulating new scenarios for situations with and without development of viable fuel cell technologies. 3) Updating software to solve the abovementioned problems. The project has identified a range of scenarios for all parts of the energy system, including most visions of possible future developments. (BA)

Calculus super review

CERN Document Server

2012-01-01

Get all you need to know with Super Reviews! Each Super Review is packed with in-depth, student-friendly topic reviews that fully explain everything about the subject. The Calculus I Super Review includes a review of functions, limits, basic derivatives, the definite integral, combinations, and permutations. Take the Super Review quizzes to see how much you've learned - and where you need more study. Makes an excellent study aid and textbook companion. Great for self-study!DETAILS- From cover to cover, each in-depth topic review is easy-to-follow and easy-to-grasp - Perfect when preparing for

Composite high-pressure vessels for hydrogen storage in mobile application. Pt. 1 / Light weight composite cylinders for compressed hydrogen. Pt. 2 - custom made hydrogen storage tanks and vessels

Energy Technology Data Exchange (ETDEWEB)

Rasche, C. [MCS Cylinder Systems GmbH, Dinslaken (Germany)

2000-07-01

Recent developments on fuel cell technology demonstrated the feasibility of propelling vehicles by converting fuel directly into electricity. Fuel cells conveniently use either compressed (CGH{sub 2}) or liquid hydrogen (LH{sub 2}) or methanol as the fuel source from a tank. Mobile storage of these fuelling will become an urgent need as this technology will come into series production expected for 2010. Due to the requirements on mobile hydrogen storage and the energy losses in the hydrogen-to-application-chain, a light-weight and energetic qualities and minimise ist bulky nature. Mobile storage of hydrogen can be realised either at high pressure values (> 20 MPa) or at deep temperatures (<-253 C). CGH{sub 2}: In the last few years, the introduction of natural gas driven vehicles has seen the development of compact mobile pressurised gas tanks in principle, this storage technique is also applicable for the compressed storage of hydrogen at filling pressures of > 20 MPa. LH{sub 2} : Storing hydrogen or natural gases in general in the liquid phase is accomplished either by applying a overpressure or keeping it below the phase transition temperature at ambient pressure in super insulated devices. (orig.)

Co-generation of hydrogen from nuclear and wind: the effect on costs of realistic variations in wind capacity and power prices

International Nuclear Information System (INIS)

Miller, A.I.; Duffey, R.

2005-01-01

Can electricity from high-capacity nuclear reactors be blended with the variable output of wind turbines to produce electrolytic hydrogen competitively? Future energy hopes and emissions reduction scenarios place significant reliance on renewables, actually meaning largely new wind power both onshore and offshore. The opportunity exists for a synergy between high capacity factor nuclear plants and wind power using hydrogen by both as a 'currency' for use in transportation and industrial processing. But this use of hydrogen needs to be introduced soon. To be competitive with alternative sources, hydrogen produced by conventional electrolysis requires low-cost electricity (likely <2.5 Cent US/kW.h). One approach is to operate interruptibly allowing an installation to sell electricity when the grid price is high and to make hydrogen when it is low. Our previous studies have shown that this could be a cost-competitive approach with a nuclear power generator producing electricity around 3 Cent US/kW.h. Although similar unit costs are projected for wind-generated electricity, idleness of the hydrogen production (electrolysis) facility due to the variability of wind generated electricity imposes a serious cost penalty. This paper reports our latest results on the potential economics of blending electricity from nuclear and wind sources by using wind-generated power, when available, to augment the current through electrolysis equipment that is primarily nuclear-powered. A voltage penalty accompanies the higher current. A 10% increase in capital cost for electrolysis equipment enables it to accommodate the higher rate of hydrogen generation, while still being substantially cheaper than the capital cost of wind-dedicated electrolysis. Real-time data for electricity costs have been combined with real-time wind variability in our NuWind model. The variability in wind fields between sites was accommodated by assuming an average wind speed that produced an average electricity

Supermanifolds and super Riemann surfaces

International Nuclear Information System (INIS)

Rabin, J.M.

1986-09-01

The theory of super Riemann surfaces is rigorously developed using Rogers' theory of supermanifolds. The global structures of super Teichmueller space and super moduli space are determined. The super modular group is shown to be precisely the ordinary modular group. Super moduli space is shown to be the gauge-fixing slice for the fermionic string path integral

Time dependent start-up thermal analysis of a Super Fast Reactor

Energy Technology Data Exchange (ETDEWEB)

Sutanto,, E-mail: sutanto@fuji.waseda.jp; Oka, Yoshiaki

2013-10-15

Highlights: • Time dependent startup thermal analysis of a Super Fast Reactor is performed. • A recirculation system is used for pressurization and for generating supercritical steam. • MCST satisfies the criterion both during subcritical pressure and during power-raising. • MCST is not sensitive to the change of inlet temperature, gap volume and flow rate because of high flow to power ratio. • CHF is not limiting the MCST during subcritical pressure due to large margin of heat flux. -- Abstract: The startup system of a supercritical pressure light water cooled fast reactor (Super FR) is studied by time dependent thermal-hydraulic analysis. The plant analysis code is developed based on an innovative upward flow pattern in all the assemblies of the Super FR. A recirculation system consisting of a steam drum, a circulation pump, and a heat exchanger is used for the startup. Detailed procedures are performed and the maximum cladding surface temperature (MCST) at rated power, 640 °C, is used as the criterion. Firstly a small constant nuclear power is used for rising the core feed water temperature to be 280 °C through the recirculation system. Secondly, pressurization is done in the recirculation system from atmospheric to operating pressure, 25 MPa, by raising the power. Thirdly, line-switching from recirculation mode to once-through direct-cycle is performed while turbines are started by supercritical steam at supercritical pressure. Finally the power is raised to be 100% of power followed by raising the flow rate. During pressurization the heat flux margin is large due to low power used for pressurization and the MCST is much lower than the criterion. The MCST is not sensitive to the inlet temperature, the flow rate, and the gap volume of the core because of high flow to power ratio. Smaller dimension of steam drum can be used for pressurization stably. The MCST satisfies the criterion both during subcritical pressure and during power-raising.

Time dependent start-up thermal analysis of a Super Fast Reactor

International Nuclear Information System (INIS)

Sutanto,; Oka, Yoshiaki

2013-01-01

Highlights: • Time dependent startup thermal analysis of a Super Fast Reactor is performed. • A recirculation system is used for pressurization and for generating supercritical steam. • MCST satisfies the criterion both during subcritical pressure and during power-raising. • MCST is not sensitive to the change of inlet temperature, gap volume and flow rate because of high flow to power ratio. • CHF is not limiting the MCST during subcritical pressure due to large margin of heat flux. -- Abstract: The startup system of a supercritical pressure light water cooled fast reactor (Super FR) is studied by time dependent thermal-hydraulic analysis. The plant analysis code is developed based on an innovative upward flow pattern in all the assemblies of the Super FR. A recirculation system consisting of a steam drum, a circulation pump, and a heat exchanger is used for the startup. Detailed procedures are performed and the maximum cladding surface temperature (MCST) at rated power, 640 °C, is used as the criterion. Firstly a small constant nuclear power is used for rising the core feed water temperature to be 280 °C through the recirculation system. Secondly, pressurization is done in the recirculation system from atmospheric to operating pressure, 25 MPa, by raising the power. Thirdly, line-switching from recirculation mode to once-through direct-cycle is performed while turbines are started by supercritical steam at supercritical pressure. Finally the power is raised to be 100% of power followed by raising the flow rate. During pressurization the heat flux margin is large due to low power used for pressurization and the MCST is much lower than the criterion. The MCST is not sensitive to the inlet temperature, the flow rate, and the gap volume of the core because of high flow to power ratio. Smaller dimension of steam drum can be used for pressurization stably. The MCST satisfies the criterion both during subcritical pressure and during power-raising

Hydrogen embrittlement in power plant steels

Indian Academy of Sciences (India)

M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

cause of blistering is well-known, handling and finishing techniques have been developed to minimize this form of damage. Vacuum melting and degassing minimize the quantity of hydrogen in the steels. Acid pickling and other such processes that may introduce hydrogen are avoided when practical, and possible moisture ...

Feasibility Study of Hydrogen Production at Existing Nuclear Power Plants

Energy Technology Data Exchange (ETDEWEB)

Stephen Schey

2009-07-01

Cooperative Agreement DE-FC07-06ID14788 was executed between the U.S. Department of Energy, Electric Transportation Applications, and Idaho National Laboratory to investigate the economics of producing hydrogen by electrolysis using electricity generated by nuclear power. The work under this agreement is divided into the following four tasks: Task 1 – Produce Data and Analyses Task 2 – Economic Analysis of Large-Scale Alkaline Electrolysis Task 3 – Commercial-Scale Hydrogen Production Task 4 – Disseminate Data and Analyses. Reports exist on the prospect that utility companies may benefit from having the option to produce electricity or produce hydrogen, depending on market conditions for both. This study advances that discussion in the affirmative by providing data and suggesting further areas of study. While some reports have identified issues related to licensing hydrogen plants with nuclear plants, this study provides more specifics and could be a resource guide for further study and clarifications. At the same time, this report identifies other area of risks and uncertainties associated with hydrogen production on this scale. Suggestions for further study in some of these topics, including water availability, are included in the report. The goals and objectives of the original project description have been met. Lack of industry design for proton exchange membrane electrolysis hydrogen production facilities of this magnitude was a roadblock for a significant period. However, recent design breakthroughs have made costing this facility much more accurate. In fact, the new design information on proton exchange membrane electrolyzers scaled to the 1 kg of hydrogen per second electrolyzer reduced the model costs from $500 to $100 million. Task 1 was delayed when the original electrolyzer failed at the end of its economic life. However, additional valuable information was obtained when the new electrolyzer was installed. Products developed during this study

Probabilistic multiobjective operation management of MicroGrids with hydrogen storage and polymer exchange fuel cell power plants

Energy Technology Data Exchange (ETDEWEB)

Niknam, T.; Golestaneh, F. [Department of Electrical and Electronics Engineering, Shiraz University of Technology, Shiraz (Iran, Islamic Republic of)

2012-10-15

This paper models and solves the operation management problem of MicroGrids (MGs) including cost and emissions minimization under uncertain environment. The proposed model emphasizes on fuel cells (FCs) as a prime mover of combined heat and power (CHP) systems. An electro-chemical model of the proton exchange membrane fuel cell (PEMFC) is used and linked to the daily operating cost and emissions of the MGs. A reformer is considered to produce hydrogen for PEMFCs. Moreover, in high thermal load intervals, in order to make the MG more efficient, a part of produced hydrogen is stored in a hydrogen tank. The stored hydrogen can be reused by PEMFCs to generate electricity or be sold to other hydrogen consumers. A probabilistic optimization algorithm is devised which consists of 2m + 1 point estimate method to handle the uncertainty in input random variables (IRVs) and a multi-objective Self-adaptive Bee Swarm Optimization (SBSO) algorithm to minimize the cost and emissions simultaneously. Several techniques are proposed in the SBSO algorithm to make it a powerful black-box optimization tool. The efficiency of the proposed approach is verified on a typical grid-connected MG with several distributed energy sources. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Super-delta: a new differential gene expression analysis procedure with robust data normalization.

Science.gov (United States)

Liu, Yuhang; Zhang, Jinfeng; Qiu, Xing

2017-12-21

Normalization is an important data preparation step in gene expression analyses, designed to remove various systematic noise. Sample variance is greatly reduced after normalization, hence the power of subsequent statistical analyses is likely to increase. On the other hand, variance reduction is made possible by borrowing information across all genes, including differentially expressed genes (DEGs) and outliers, which will inevitably introduce some bias. This bias typically inflates type I error; and can reduce statistical power in certain situations. In this study we propose a new differential expression analysis pipeline, dubbed as super-delta, that consists of a multivariate extension of the global normalization and a modified t-test. A robust procedure is designed to minimize the bias introduced by DEGs in the normalization step. The modified t-test is derived based on asymptotic theory for hypothesis testing that suitably pairs with the proposed robust normalization. We first compared super-delta with four commonly used normalization methods: global, median-IQR, quantile, and cyclic loess normalization in simulation studies. Super-delta was shown to have better statistical power with tighter control of type I error rate than its competitors. In many cases, the performance of super-delta is close to that of an oracle test in which datasets without technical noise were used. We then applied all methods to a collection of gene expression datasets on breast cancer patients who received neoadjuvant chemotherapy. While there is a substantial overlap of the DEGs identified by all of them, super-delta were able to identify comparatively more DEGs than its competitors. Downstream gene set enrichment analysis confirmed that all these methods selected largely consistent pathways. Detailed investigations on the relatively small differences showed that pathways identified by super-delta have better connections to breast cancer than other methods. As a new pipeline, super

A lignite-geothermal hybrid power and hydrogen production plant for green cities and sustainable buildings

Energy Technology Data Exchange (ETDEWEB)

Kilkis, B. [Baskent University, Ankara (Turkey). Dept. of Mechanical Engineering

2011-02-15

Turkey is rich in both geothermal energy and lignite reserves, which in many cases, are co-located. This condition makes it feasible to utilize both lignite and geothermal energy in a hybrid form for combined power heat, and cold generation, which may lead to optimally energy and exergy efficient, environmentally benign, and economically sound applications. This paper presents a novel concept of hybrid lignite-geothermal plant for a district energy system and hydrogen production facility in Aydin with special emphasis on high performance, green buildings and green districts. In this concept, lignite is first introduced to a partially fluidized-bed gasifier and then to a fluidized-bed gas cleaning unit, which produces synthetic gas and finally hydrogen. The by-products, namely char and ash are used in a fluidized-bed combustor to produce power. Waste heat from all these steps are utilized in a district heating system along with heat received from geothermal production wells after power is generated there. H{sub 2}S gas obtained from the separator system is coupled with hydrogen production process at the lignite plant. Absorption cooling systems and thermal storage tanks complement the hybrid system for the tri-generation district energy system. On the demand side, the new, green OSTIM OSB administration building in Ankara is exemplified for greener, low-exergy buildings that will compound the environmental benefits.

Deterministic phase measurements exhibiting super-sensitivity and super-resolution

DEFF Research Database (Denmark)

Schäfermeier, Clemens; Ježek, Miroslav; Madsen, Lars S.

2018-01-01

Phase super-sensitivity is obtained when the sensitivity in a phase measurement goes beyond the quantum shot noise limit, whereas super-resolution is obtained when the interference fringes in an interferometer are narrower than half the input wavelength. Here we show experimentally that these two...

Evaluation of mini super computers for nuclear design applications

International Nuclear Information System (INIS)

Altomare, S.; Baradari, F.

1987-01-01

The evolution of the mini super computers will force changes from the current environment of performing nuclear design calculations on mainframe computers (such as a CRAY) to mini super computers. This change will come about for a number of reasons. First, the mini super computers currently available in the marketplace offer the power and speed comparable to mainframes and can provide the capability to support highly computer intensive calculations. Second, the equipment is physically smaller and can easily be installed and operated without extensive investments in facilities and operations support. Third, the computer capacity can be acquired with as much needed memory, disk, and tape capacity as may be needed. Another reasons is that the performance/cost ratio has increased drastically as hardware costs have decreased. A study was conducted at the Westinghouse Commercial Nuclear Fuel Division (CNFD) to evaluate the mini super computers for use in nuclear core design. As a result of this evaluation, Westinghouse CNFD is offering a combined hardware/software technology transfer package for core design. This package provides the utility designer with a totally dedicated mini super computer comparable in speed to the CRAY 1S with sufficient capacity for a sizable design group to perform the engineering activities related to nuclear core design and operations support. This also assures the utility of being totally compatible with the CNFD design codes, thus assuring total update compatibility

Techno-economical Analysis of Hybrid PV-WT-Hydrogen FC System for a Residential Building with Low Power Consumption

Directory of Open Access Journals (Sweden)

Badea G.

2016-12-01

Full Text Available This paper shows a techno-economical analysis on performance indicators of hybrid solar-wind-hydrogen power generation system which supply with electricity a low - energy building, located in Cluj-Napoca. The case study had the main objectives, as follows: cost estimation, evaluation of energy and environmental performance for a fuel cell integrated into a small-scale hybrid system power generation and estimation of electrolytic hydrogen production based on renewable energy resources available on the proposed site. The results presented in this paper illustrate a case study for location Cluj-Napoca. The wind and solar resource can play an important role in energy needs for periods with "peak load" or intermittent energy supply. However, hydrogen production is dependent directly proportional to the availability of renewable energy resources, but the hydrogen can be considered as a storage medium for these renewable resources. It can be said that this study is a small-scale model analysis, a starting point for a detailed analysis of Romania's potential electrolytic production of hydrogen from renewable resources and supply electricity using fuel cells integrated into hybrid energy systems.

CFD analyses of steam and hydrogen distribution in a nuclear power plant

International Nuclear Information System (INIS)

Siccama, N.B.; Houkema, M.; Komen, E.M.J.

2003-01-01

A detailed three-dimensional Computational Fluid Dynamics (CFD) model of the containment of the nuclear power plant has been prepared in order to assess possible multidimensional phenomena. In a first code-to-code comparison step, the CFD model has been used to compute a reference accident scenario which has been analysed earlier with the lumped parameter code SPECTRA. The CFD results compare qualitatively well with the SPECTRA results. Subsequently, the actual steam jet from the primary system has been modelled in the CFD code in order to determine the hydrogen distribution for this realistically modelled source term. Based on the computed hydrogen distributions, it has been determined when use of lumped parameter codes is allowed and when use of CFD codes is required. (author)

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

International Nuclear Information System (INIS)

Lukyanov, Boris N

2008-01-01

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

Clean energy and the hydrogen economy.

Science.gov (United States)

Brandon, N P; Kurban, Z

2017-07-28

In recent years, new-found interest in the hydrogen economy from both industry and academia has helped to shed light on its potential. Hydrogen can enable an energy revolution by providing much needed flexibility in renewable energy systems. As a clean energy carrier, hydrogen offers a range of benefits for simultaneously decarbonizing the transport, residential, commercial and industrial sectors. Hydrogen is shown here to have synergies with other low-carbon alternatives, and can enable a more cost-effective transition to de-carbonized and cleaner energy systems. This paper presents the opportunities for the use of hydrogen in key sectors of the economy and identifies the benefits and challenges within the hydrogen supply chain for power-to-gas, power-to-power and gas-to-gas supply pathways. While industry players have already started the market introduction of hydrogen fuel cell systems, including fuel cell electric vehicles and micro-combined heat and power devices, the use of hydrogen at grid scale requires the challenges of clean hydrogen production, bulk storage and distribution to be resolved. Ultimately, greater government support, in partnership with industry and academia, is still needed to realize hydrogen's potential across all economic sectors.This article is part of the themed issue 'The challenges of hydrogen and metals'. © 2017 The Author(s).

Combined production of hydrogen and power from heavy oil gasification: Pinch analysis, thermodynamic and economic evaluations

Energy Technology Data Exchange (ETDEWEB)

Domenichini, R.; Gallio, M. [Foster Wheeler Italiana Spa, via Caboto 1, 20094 Corsico (Milano) (Italy); Lazzaretto, A. [University of Padova, Department of Mechanical Engineering, via Venezia 1, 35131 Padova (Italy)

2010-05-15

Integrated Gasification Combined Cycle (IGCC) represents a commercially proven technology available for the combined production of hydrogen and electricity power from coal and heavy residue oils. When associated with CO{sub 2} capture and sequestration facilities, the IGCC plant gives an answer to the search for a clean and environmentally compatible use of high sulphur and heavy metal contents fuels, the possibility of installing large size plants for competitive electric power and hydrogen production, and a low cost of CO{sub 2} avoidance. The paper describes two new and realistic configurations of IGCC plant fed by refinery heavy residues and including a CO{sub 2} capture section, which are proposed on the basis of the experience gained in the construction of similar plants. They are based on oxygen blown entrained bed gasification and sized to produce a large amount of hydrogen and to feed one or two gas turbines of the combined cycle unit. The main thermodynamic and technological characteristics of the total plants are evaluated focusing on the heat integration between syngas cooling and combined cycle sections. Moreover, the overall performance characteristics and investment cost are estimated to supply a reliable estimate for the cost of electricity, given a value for the hydrogen selling price. (author)

Combined production of hydrogen and power from heavy oil gasification: Pinch analysis, thermodynamic and economic evaluations

International Nuclear Information System (INIS)

Domenichini, R.; Gallio, M.; Lazzaretto, A.

2010-01-01

Integrated Gasification Combined Cycle (IGCC) represents a commercially proven technology available for the combined production of hydrogen and electricity power from coal and heavy residue oils. When associated with CO 2 capture and sequestration facilities, the IGCC plant gives an answer to the search for a clean and environmentally compatible use of high sulphur and heavy metal contents fuels, the possibility of installing large size plants for competitive electric power and hydrogen production, and a low cost of CO 2 avoidance. The paper describes two new and realistic configurations of IGCC plant fed by refinery heavy residues and including a CO 2 capture section, which are proposed on the basis of the experience gained in the construction of similar plants. They are based on oxygen blown entrained bed gasification and sized to produce a large amount of hydrogen and to feed one or two gas turbines of the combined cycle unit. The main thermodynamic and technological characteristics of the total plants are evaluated focusing on the heat integration between syngas cooling and combined cycle sections. Moreover, the overall performance characteristics and investment cost are estimated to supply a reliable estimate for the cost of electricity, given a value for the hydrogen selling price.

Hydrogen/oxygen injection stopping method for nuclear power plant and emergent hydrogen/oxygen injection device

International Nuclear Information System (INIS)

Ishida, Ryoichi; Ota, Masamoto; Takagi, Jun-ichi; Hirose, Yuki

1998-01-01

The present invention provides a device for suppressing increase of electroconductivity of reactor water during operation of a BWR type reactor, upon occurrence of reactor scram of the plant or upon stopping of hydrogen/oxygen injection due to emergent stoppage of an injection device so as not to deteriorate the integrity of a gas waste processing system upon occurrence of scram. Namely, when injection of hydrogen/oxygen is stopped during plant operation, the injection amount of hydrogen is reduced gradually. Subsequently, injection of hydrogen is stopped. With such procedures, the increase of electroconductivity of reactor water can be suppressed upon stoppage of hydrogen injection. When injection of hydrogen/oxygen is stopped upon shut down of the plant, the amount of hydrogen injection is changed depending on the change of the feedwater flow rate, and then the plant is shut down while keeping hydrogen concentration of feedwater to a predetermined value. With such procedures, increase of the reactor water electroconductivity can be suppressed upon stoppage of hydrogen injection. Upon emergent stoppage of the hydrogen/oxygen injection device, an emergent hydrogen/oxygen injection device is actuated to continue the injection of hydrogen/oxygen. With such procedures, elevation of reactor water electroconductivity can be suppressed. (I.S.)

Hydrogen highway

International Nuclear Information System (INIS)

Anon

2008-01-01

The USA Administration would like to consider the US power generating industry as a basis ensuring both the full-scale production of hydrogen and the widespread use of the hydrogen related technological processes into the economy [ru

Theory of super LIE groups

International Nuclear Information System (INIS)

Prakash, M.

1985-01-01

The theory of supergravity has attracted increasing attention in the recent years as a unified theory of elementary particle interactions. The superspace formulation of the theory is highly suggestive of an underlying geometrical structure of superspace. It also incorporates the beautifully geometrical general theory of relativity. It leads us to believe that a better understanding of its geometry would result in a better understanding of the theory itself, and furthermore, that the geometry of superspace would also have physical consequences. As a first step towards that goal, we develop here a theory of super Lie groups. These are groups that have the same relation to a super Lie algebra as Lie groups have to a Lie algebra. More precisely, a super Lie group is a super-manifold and a group such that the group operations are super-analytic. The super Lie algebra of a super Lie group is related to the local properties of the group near the identity. This work develops the algebraic and super-analytical tools necessary for our theory, including proofs of a set of existence and uniqueness theorems for a class of super-differential equations

Tohyco-Rider: hybrid bus with super-caps and inductive power transfer

Energy Technology Data Exchange (ETDEWEB)

Harri, V.; Carriero, D. [HTA Luzern, Horw (Switzerland)

2004-07-01

The TOHYCO-Rider-Bus was developed during a Swiss research project at HTA Lucerne (University of Applied Sciences of Central Switzerland). Each time, the bus only picks up enough energy to safely reach the next charging station. Instead of common re-chargeable batteries, the TOHYCO-Rider uses electrical high-power capacitors, so-called super-capacitors, as energy storage. In combination with an absolutely non-dangerous, non-contact, inductive energy re-charging system the S-CAPs can be reloaded with a higher efficiency and much more quickly than batteries. Within 3-5 minutes of charging time the vehicle is prepared for its next trip. A further advantage of this concept is that, with the S-CAPs, only the energy supply has to be taken along for the next stop (approx. 300 kg) and not a charge of batteries for the entire day (approx. 2t). Because of the lighter weight, the TOHYCO-Rider is therefore an economically and ecologically interesting mean of transportation. In summer 2004 the TOHYCO-Rider ran in a pilot operation. During three months the mini-bus drove in a time-scheduled operation in the city of Lucerne, with the aim of proving the reliability and fitness of the developed system in daily operation. The test operation was terminated recently and the results were very promising. (authors)

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

KAUST Repository

Burhan, Muhammad

2017-12-27

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

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

KAUST Repository

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

2017-01-01

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

Algebra & trigonometry super review

CERN Document Server

2012-01-01

Get all you need to know with Super Reviews! Each Super Review is packed with in-depth, student-friendly topic reviews that fully explain everything about the subject. The Algebra and Trigonometry Super Review includes sets and set operations, number systems and fundamental algebraic laws and operations, exponents and radicals, polynomials and rational expressions, equations, linear equations and systems of linear equations, inequalities, relations and functions, quadratic equations, equations of higher order, ratios, proportions, and variations. Take the Super Review quizzes to see how much y

Calculations of high-power production target and beamdump for the GSI future Super-FRS for a fast extraction scheme at the FAIR Facility

International Nuclear Information System (INIS)

Tahir, N A; Weick, H; Iwase, H

2005-01-01

A superconducting fragment separator (Super-FRS) is being designed for the production and separation of radioactive isotopes at the future FAIR (Facility for Antiprotons and Ion Research) facility at Darmstadt. This paper discusses various aspects and requirements for the high-power production target that will be used in the Super-FRS experiments. The production target must survive over an extended period of time as it will be used during the course of many experiments. The specific power deposited by the high intensity beam that will be generated at the future FAIR facility will be high enough to destroy the target in most of the cases as a result of a single shot from the new heavy ion synchrotrons SIS100/300. By using an appropriate beam intensity and focal spot parameters, the target would survive after being irradiated once. However, the heat should be dissipated efficiently before the same target area is irradiated again. We have considered a wheel shaped solid carbon target that rotates around its axis so that different areas of the target are irradiated successively. This allows for cooling of the beam heated region by thermal conduction before the same part of the target is irradiated a second time. Another attractive option is to use a liquid jet target at the Super-FRS. First calculations of a possible liquid lithium target are also presented in this paper. One of the advantages of using lithium as a target is that it will survive even if one uses a smaller focal spot, which has half the area of that used for a solid carbon target. This will significantly improve the isotope resolution. A similar problem associated with these experiments will be safe deposition of the beam energy in a beamdump after its interaction with the production target. We also present calculations to study the suitability of a proposed beamdump

Wavelet analysis of cyclic variability in a spark ignition engine powered by gasoline-hydrogen fuel blends

Energy Technology Data Exchange (ETDEWEB)

Sen, Asok K. [Richard G. Lugar Centre for Renewable Energy, and Department of Mathematical Sciences, Indiana University, (United States)], email: asen@iupui.edu; Akif Ceviz, M.; Volkan Oner, I. [Department of Mechanical Engineering, University of Ataturk (Turkey)], email: aceviz@atauni.edu.tr

2011-07-01

The cycle-to-cycle variations (CCV) of the indicated mean effective pressure (IMEP) in a spark ignition engine fuelled by gasoline and gasoline-hydrogen blends is investigated. CCVs are estimated by using the coefficient of variation (COV) and the overall spectral power given by the global wavelet spectrum (GWS). It was found that the addition of hydrogen reduces the CCV of the IMEP. Analysis of the wavelet can also identify the dominant modes of variability and delineate the engine cycles over which these modes can persist. Air-fuel ratio was varied from 1.0 to 1.3, and hydrogen was added up to 7.74% by volume. The engine was operated at 2000 rpm. Results demonstrate that subject to air-fuel ratio and % of hydrogen added, IMEP time series can exhibit multiscale dynamics consisting of persistent oscillations and intermittent fluctuations. These results can help develop effective control strategies to reduce cyclic variability in a spark ignition engine fuelled by gasoline-hydrogen mixtures.

Development of Automotive Liquid Hydrogen Storage Systems

Science.gov (United States)

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

2004-06-01

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

Study on design of light-weight super-abrasive wheel

Science.gov (United States)

Nohara, K.; Yanagihara, K.; Ogawa, M.

2018-01-01

Fixed-abrasive tool, also called a grinding wheel, is produced by furnacing abrasive compound which contains abrasive grains and binding powder such as vitrified materials or resins. Fixed-abrasive tool is installed on spindle of grinding machine. And it is given 1,800-2,000 min-1 of spindle rotation for the usage. The centrifugal fracture of the compound of fixed- abrasive tool is one of the careful respects in designing. In recent years, however, super-abrasive wheel as a fixed-abrasive tool has been developed and applied widely. One of the most characteristic respects is that metal is applied for the body of grinding-wheel. The strength to hold abrasive grain and the rigidity of wheel become stronger than those of general grinding wheel, also the lifespan of fixed-abrasive tool becomes longer. The weight of fixed-abrasive tool, however, becomes heavier. Therefore, when the super-abrasive wheel is used, the power consumption of spindle motor becomes larger. It also becomes difficult for the grinding-wheel to respond to sudden acceleration or deceleration. Thus, in order to reduce power consumption in grinding and to obtain quicker frequency response of super-abrasive wheel, the new wheel design is proposed. The design accomplishes 46% weight reduction. Acceleration that is one second quicker than that of conventional grinding wheel is obtained.

Hydrogen: it's now. Hydrogen, essential today, indispensable tomorrow. Power-to-Gas or how to meet the challenge of electricity storage. To develop hydrogen mobility. Hydrogen production modes and scope of application of the IED directive - Interview. Regulatory evolutions needed for an easier deployment of hydrogen energy technologies for a clean mobility. Support of the Community's policy to hydrogen and to fuel cells

International Nuclear Information System (INIS)

Mauberger, Pascal; Boucly, Philippe; Quint, Aliette; Pierre, Helene; Lucchese, Paul; Bouillon-Delporte, Valerie; Chauvet, Bertrand; Ferrari, Fabio; Boivin, Jean-Pierre

2015-01-01

Published by the French Association for Hydrogen and Fuel Cells (AFHYPAC), this document first outlines how hydrogen can reduce our dependence on fossil energies, how it supports the development of electric mobility to reduce CO 2 emissions by transports, how it enables a massive storage of energy as a support to renewable energies deployment and integration, and how hydrogen can be a competitiveness driver. Then two contributions address technical solutions, the first one being Power-to-Gas as a solution to energy storage (integration of renewable energies, a mean for massive storage of electricity, economic conditions making the first deployments feasible, huge social and economical benefits, necessity of creation of an adapted legal and economic framework), and the second one being the development of hydrogen-powered mobility (a major societal concern for air quality, strategies of car manufacturers in the world, necessity of a favourable framework, the situation of recharging infrastructures). Two contributions address the legal framework regarding hydrogen production modes and the scope of application of the European IED directive on industrial emissions, and the needed regulatory evolutions for an easier deployment of Hydrogen-energy technologies for a clean mobility. A last article comments the evolution of the support of European policies to hydrogen and fuel cells through R and d programs, presents the main support program (FCH JU) and its results, other European financing and support policy, and discusses perspectives, notably for possible financing mechanisms

Melting in super-earths.

Science.gov (United States)

Stixrude, Lars

2014-04-28

We examine the possible extent of melting in rock-iron super-earths, focusing on those in the habitable zone. We consider the energetics of accretion and core formation, the timescale of cooling and its dependence on viscosity and partial melting, thermal regulation via the temperature dependence of viscosity, and the melting curves of rock and iron components at the ultra-high pressures characteristic of super-earths. We find that the efficiency of kinetic energy deposition during accretion increases with planetary mass; considering the likely role of giant impacts and core formation, we find that super-earths probably complete their accretionary phase in an entirely molten state. Considerations of thermal regulation lead us to propose model temperature profiles of super-earths that are controlled by silicate melting. We estimate melting curves of iron and rock components up to the extreme pressures characteristic of super-earth interiors based on existing experimental and ab initio results and scaling laws. We construct super-earth thermal models by solving the equations of mass conservation and hydrostatic equilibrium, together with equations of state of rock and iron components. We set the potential temperature at the core-mantle boundary and at the surface to the local silicate melting temperature. We find that ancient (∼4 Gyr) super-earths may be partially molten at the top and bottom of their mantles, and that mantle convection is sufficiently vigorous to sustain dynamo action over the whole range of super-earth masses.

Water electrolysis plants for hydrogen and oxygen production. Shipped to Tsuruga Power Station Unit No.1, and Tokai No.2 power station, the Japan Atomic Power Co

International Nuclear Information System (INIS)

Ueno, Syuichi; Sato, Takao; Ishikawa, Nobuhide

1997-01-01

Ebara's water electrolysis plants have been shipped to Tsuruga Power Station Unit No.1, (H 2 generation rate: 11 Nm 3 /h), and Tokai No.2 Power Station (H 2 generation rate: 36 Nm 3 /h), Japan Atomic Power Co. An outcome of a business agreement between Nissho Iwai Corporation and Norsk Hydro Electrolysers (Norway), this was the first time that such water electrolysis plants were equipped in Japanese boiling water reactor power stations. Each plant included an electrolyser (for generating hydrogen and oxygen), an electric power supply, a gas compression system, a dehumidifier system, an instrumentation and control system, and an auxiliary system. The plant has been operating almost continuously, with excellent feedback, since March 1997. (author)

Integration of hydrogen energy technologies in stand-alone power systems analysis of the current potential for applications

International Nuclear Information System (INIS)

Zoulias, E.I.; Lymberopoulos, N.; Tsoutsos, T.; Glockner, R.; Mydske, H.J.; Vosseler, I.; Gavalda, O.; Taylor, P.

2006-01-01

The European study entitled: 'Market Potential Analysis for Introduction of Hydrogen Energy Technology in Stand-Alone Power Systems (H-SAPS)' aimed to establish a broad understanding of the market potential for H-SAPS and provide a basis for promoting in wide scale new technological applications. The scope of the study was limited to small and medium installations, up to a few hundred kW power rating and based on RE as the primary energy source. The potential for hydrogen technology in SAPS was investigated through an assessment of the technical potential for hydrogen, the market analysis and the evaluation of external factors. The results are mostly directed towards action by governments and the research community but also industry involvement is identified. The results include targeted market research, establishment of individual cost targets, regulatory changes to facilitate alternative grid solutions, information and capacity building, focused technology research and bridging the technology gaps. (author)

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

Energy Technology Data Exchange (ETDEWEB)

Wurster, R

1989-01-01

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

Sizing Hydrogen Energy Storage in Consideration of Demand Response in Highly Renewable Generation Power Systems

Directory of Open Access Journals (Sweden)

Mubbashir Ali

2018-05-01

Full Text Available From an environment perspective, the increased penetration of wind and solar generation in power systems is remarkable. However, as the intermittent renewable generation briskly grows, electrical grids are experiencing significant discrepancies between supply and demand as a result of limited system flexibility. This paper investigates the optimal sizing and control of the hydrogen energy storage system for increased utilization of renewable generation. Using a Finnish case study, a mathematical model is presented to investigate the optimal storage capacity in a renewable power system. In addition, the impact of demand response for domestic storage space heating in terms of the optimal sizing of energy storage is discussed. Finally, sensitivity analyses are conducted to observe the impact of a small share of controllable baseload production as well as the oversizing of renewable generation in terms of required hydrogen storage size.

The super collider revisited

International Nuclear Information System (INIS)

Hussein, M.S.; Pato, M.P.

1992-01-01

In this paper, the authors suggest a revised version of the Superconducting Super Collider (SSC) that employs the planned SSC first stage machine as an injector of 0.5 TeV protons into a power laser accelerator. The recently developed Non-linear Amplification of Inverse Bremsstrahlung Acceleration (NAIBA) concept dictates the scenario of the next stage of acceleration. Post Star Wars lasers, available at several laboratories, can be used for the purpose. The 40 TeV CM energy, a target of the SSC, can be obtained with a new machine which can be 20 times smaller than the planned SSC

Influence of Microwave Power on the Properties of Hydrogenated Diamond-Like Carbon Films Prepared by ECR Plasma Enhanced DC Magnetron Sputtering

International Nuclear Information System (INIS)

Ru Lili; Huang Jianjun; Gao Liang; Qi Bing

2010-01-01

Electron cyclotron resonance (ECR) plasma was applied to enhance the direct current magnetron sputtering to prepare hydrogenated diamond-like carbon (H-DLC) films. For different microwave powers, both argon and hydrogen gas are introduced separately as the ECR working gas to investigate the influence of microwave power on the microstructure and electrical property of the H-DLC films deposited on P-type silicon substrates. A series of characterization methods including the Raman spectrum and atomic force microscopy are used. Results show that, within a certain range, the increase in microwave power affects the properties of the thin films, namely the sp 3 ratio, the hardness, the nanoparticle size and the resistivity all increase while the roughness decreases with the increase in microwave power. The maximum of resistivity amounts to 1.1 x 10 9 Ω · cm. At the same time it is found that the influence of microwave power on the properties of H-DLC films is more pronounced when argon gas is applied as the ECR working gas, compared to hydrogen gas.

Implementation of hydrogen mitigation techniques during severe accidents in nuclear power plants

International Nuclear Information System (INIS)

1996-01-01

concentration and under special geometric conditions, an accelerated flame or even a local detonation may occur which would produce higher dynamic loads than a deflagration and a more serious threat to equipment and structures. Should it occur in spite of its low probability, a global detonation, following prolonged and extensive accumulation of hydrogen in the containment atmosphere, would be a major threat to the containment integrity. The goal of hydrogen mitigation techniques is to prevent loads, resulting from hydrogen combustion, which could threaten containment integrity. The risk of containment failure depends on the overall hydrogen concentration which is dependent on the amount of hydrogen released and the containment volume. A possible containment failure also depends on the containment structure and design which is very important in the resistance of the containment to a global combustion. Geometrical sub-compartmentalization is also very important, because significant amounts of hydrogen could accumulate in compartments to create high local concentrations of hydrogen that could be well within the detonability limits. Once accident management measures aimed at preventing severe accidents from occurring have failed and hydrogen is being generated and released to the containment atmosphere in large amounts, the first step is to reduce the possibility of hydrogen accumulating to flammable concentrations. Where flammable concentrations cannot be precluded, the next step is to minimize the volume of gas at flammable concentrations and the third and last step is to prevent further increasing hydrogen levels from the flammable to detonable mixture concentrations. The purpose of this paper is to present a snapshot, from a technical viewpoint, of the current situation regarding the implementation of hydrogen mitigation techniques for severe accident conditions in nuclear power plants. Broader aspects related to overall accident management policies are not considered here

SuperB Progress Report: Detector

Energy Technology Data Exchange (ETDEWEB)

Grauges, E.; /Barcelona U., ECM; Donvito, G.; Spinoso, V.; /INFN, Bari /Bari U.; Manghisoni, M.; Re, V.; Traversi, G.; /INFN, Pavia /Bergamo U., Ingengneria Dept.; Eigen, G.; Fehlker, D.; Helleve, L.; /Bergen U.; Carbone, A.; Di Sipio, R.; Gabrielli, A.; Galli, D.; Giorgi, F.; Marconi, U.; Perazzini, S.; Sbarra, C.; Vagnoni, V.; Valentinetti, S.; Villa, M.; Zoccoli, A.; /INFN, Bologna /Bologna U. /Caltech /Carleton U. /Cincinnati U. /INFN, CNAF /INFN, Ferrara /Ferrara U. /UC, Irvine /Taras Shevchenko U. /Orsay, LAL /LBL, Berkeley /UC, Berkeley /Frascati /INFN, Legnaro /Orsay, IPN /Maryland U. /McGill U. /INFN, Milan /Milan U. /INFN, Naples /Naples U. /Novosibirsk, IYF /INFN, Padua /Padua U. /INFN, Pavia /Pavia U. /INFN, Perugia /Perugia U. /INFN, Perugia /Caltech /INFN, Pisa /Pisa U. /Pisa, Scuola Normale Superiore /PNL, Richland /Queen Mary, U. of London /Rutherford /INFN, Rome /Rome U. /INFN, Rome2 /Rome U.,Tor Vergata /INFN, Rome3 /Rome III U. /SLAC /Tel Aviv U. /INFN, Turin /Turin U. /INFN, Padua /Trento U. /INFN, Trieste /Trieste U. /TRIUMF /British Columbia U. /Montreal U. /Victoria U.

2012-02-14

This report describes the present status of the detector design for SuperB. It is one of four separate progress reports that, taken collectively, describe progress made on the SuperB Project since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008.

SuperB Progress Report: Detector

International Nuclear Information System (INIS)

Grauges, E.; Donvito, G.; Spinoso, V.; Manghisoni, M.; Re, V.; Traversi, G.; Eigen, G.; Fehlker, D.; Helleve, L.; Cheng, C.; Chivukula, A.; Doll, D.; Echenard, B.; Hitlin, D.; Ongmongkolkul, P.; Porter, F.; Rakitin, A.; Thomas, M.; Zhu, R.; Tatishvili, G.; Andreassen, R.; Fabby, C.; Meadows, B.; Simpson, A.; Sokoloff, M.; Tomko, K.; Fella, A.; Andreotti, M.; Baldini, W.; Calabrese, R.; Carassiti, V.; Cibinetto, G.; Cotta Ramusino, A.; Gianoli, A.; Luppi, E.; Munerato, M.; Santoro, V.; Tomassetti, L.; Stoker, D.; Bezshyyko, O.; Dolinska, G.; Arnaud, N.; Beigbeder, C.; Bogard, F.; Breton, D.; Burmistrov, L.; Charlet, D.; Maalmi, J.; Perez Perez, L.; Puill, V.; Stocchi, A.; Tocut, V.; Wallon, S.; Wormser, G.; Brown, D.

2012-01-01

This report describes the present status of the detector design for SuperB. It is one of four separate progress reports that, taken collectively, describe progress made on the SuperB Project since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008.

SuperB Progress Reports Accelerator

CERN Document Server

Biagini, Maria Enrica; Boscolo, M; Buonomo, B; Demma, T; Drago, A; Esposito, M; Guiducci, S; Mazzitelli, G; Pellegrino, L; Preger, M A; Raimondi, P; Ricci, R; Rotundo, U; Sanelli, C; Serio, M; Stella, A; Tomassini, S; Zobov, M; Bertsche, K; Brachman, A; Cai, Y; Chao, A; Chesnut, R; Donald, M.H; Field, C; Fisher, A; Kharakh, D; Krasnykh, A; Moffeit, K; Nosochkov, Y; Pivi, M; Seeman, J; Sullivan, M.K; Weathersby, S; Weidemann, A; Weisend, J; Wienands, U; Wittmer, W; Woods, M; Yocky, G; Bogomiagkov, A; Koop, I; Levichev, E; Nikitin, S; Okunev, I; Piminov, P; Sinyatkin, S; Shatilov, D; Vobly, P; Bosi, F; Liuzzo, S; Paoloni, E; Bonis, J; Chehab, R; Le Meur, G; Lepercq, P; Letellier-Cohen, F; Mercier, B; Poirier, F; Prevost, C; Rimbault, C; Touze, F; Variola, A; Bolzon, B; Brunetti, L; Jeremie, A; Baylac, M; Bourrion, O; De Conto, J M; Gomez, Y; Meot, F; Monseu, N; Tourres, D; Vescovi, C; Chanci, A; Napoly, O; Barber, D P; Bettoni, S; Quatraro, D

2010-01-01

This report details the present status of the Accelerator design for the SuperB Project. It is one of four separate progress reports that, taken collectively, describe progress made on the SuperB Project since the publication of the SuperB Conceptual Design Report in 2007 and the Proceedings of SuperB Workshop VI in Valencia in 2008.

Optimal Sizing of a Stand-Alone Hybrid Power System Based on Battery/Hydrogen with an Improved Ant Colony Optimization

Directory of Open Access Journals (Sweden)

Weiqiang Dong

2016-09-01

Full Text Available A distributed power system with renewable energy sources is very popular in recent years due to the rapid depletion of conventional sources of energy. Reasonable sizing for such power systems could improve the power supply reliability and reduce the annual system cost. The goal of this work is to optimize the size of a stand-alone hybrid photovoltaic (PV/wind turbine (WT/battery (B/hydrogen system (a hybrid system based on battery and hydrogen (HS-BH for reliable and economic supply. Two objectives that take the minimum annual system cost and maximum system reliability described as the loss of power supply probability (LPSP have been addressed for sizing HS-BH from a more comprehensive perspective, considering the basic demand of load, the profit from hydrogen, which is produced by HS-BH, and an effective energy storage strategy. An improved ant colony optimization (ACO algorithm has been presented to solve the sizing problem of HS-BH. Finally, a simulation experiment has been done to demonstrate the developed results, in which some comparisons have been done to emphasize the advantage of HS-BH with the aid of data from an island of Zhejiang, China.

A hybrid power system for unmanned aerial vehicle electromagnetic launcher

Science.gov (United States)

Wang, Zhiren; Wu, Jun; Huang, Shengjun

2018-06-01

According to the UAV electromagnetic catapult with fixed timing, a hybrid energy storage system consist with battery and super capacitor is designed, in order to reduce the volume and weight of the energy storage system. The battery is regarded as the energy storage device and the super capacitor as power release device. Firstly, the battery charges the super capacitor, and then the super capacitor supplies power to electromagnetic catapult separately. The strategy is using the Buck circuit to charge the super capacitor with constant current and using the Boost circuit to make super capacitor provide a stable voltage circuit for electromagnetic catapult. The Simulink simulation results show that the designed hybrid energy storage system can meet the requirements of electromagnetic catapult. Compared with the system powered by the battery alone, the proposed scheme can reduce the number of batteries, and greatly reduce the volume and weight of the energy storage system.

Deformations of super Riemann surfaces

International Nuclear Information System (INIS)

Ninnemann, H.

1992-01-01

Two different approaches to (Konstant-Leites-) super Riemann surfaces are investigated. In the local approach, i.e. glueing open superdomains by superconformal transition functions, deformations of the superconformal structure are discussed. On the other hand, the representation of compact super Riemann surfaces of genus greater than one as a fundamental domain in the Poincare upper half-plane provides a simple description of super Laplace operators acting on automorphic p-forms. Considering purely odd deformations of super Riemann surfaces, the number of linear independent holomorphic sections of arbitrary holomorphic line bundles will be shown to be independent of the odd moduli, leading to a simple proof of the Riemann-Roch theorem for compact super Riemann surfaces. As a further consequence, the explicit connections between determinants of super Laplacians and Selberg's super zeta functions can be determined, allowing to calculate at least the 2-loop contribution to the fermionic string partition function. (orig.)

Deformations of super Riemann surfaces

Energy Technology Data Exchange (ETDEWEB)

Ninnemann, H [Hamburg Univ. (Germany). 2. Inst. fuer Theoretische Physik

1992-11-01

Two different approaches to (Konstant-Leites-) super Riemann surfaces are investigated. In the local approach, i.e. glueing open superdomains by superconformal transition functions, deformations of the superconformal structure are discussed. On the other hand, the representation of compact super Riemann surfaces of genus greater than one as a fundamental domain in the Poincare upper half-plane provides a simple description of super Laplace operators acting on automorphic p-forms. Considering purely odd deformations of super Riemann surfaces, the number of linear independent holomorphic sections of arbitrary holomorphic line bundles will be shown to be independent of the odd moduli, leading to a simple proof of the Riemann-Roch theorem for compact super Riemann surfaces. As a further consequence, the explicit connections between determinants of super Laplacians and Selberg's super zeta functions can be determined, allowing to calculate at least the 2-loop contribution to the fermionic string partition function. (orig.).

The safe production of hydrogen by nuclear power

International Nuclear Information System (INIS)

Verfondern, Karl

2009-01-01

One of the most promising 'GEN-IV' nuclear reactor concepts is the Very High Temperature Reactor (VHTR). It is characterized by a helium-cooled, graphite moderated, thermal neutron spectrum reactor core of 400-600 MW(th). Coolant outlet temperatures of 900-1000 .deg. C ideally suited for a wide spectrum of high temperature process heat or process steam applications, which allow to deliver, besides the classical electricity, also non-electrical products such as hydrogen or other fuels. In a future energy economy, hydrogen as a storable medium could adjust a variable demand for electricity by means of fuel cell power plants providing much more flexibility in optimized energy structures. The mass production of hydrogen is a major goal for Gen-IV systems. In a nuclear hydrogen production facility, the coupling between the nuclear plant and the process heat/steam application side is given by an intermediate heat exchanger (IHX), a component which provides a clear separation preventing the primary coolant from accessing the heat application plant and, vice versa, any process gases from being routed through the reactor containment. The physical separation has the advantage that the heat application facility can be conventionally designed, and repair works can be conducted under non-nuclear conditions. With regard to the safety of combined nuclear and chemical facilities, apart from their own specific categories of hazards, a qualitatively new class of events will have to be taken into account characterized by interacting influences. Arising problems to be covered by a decent overall safety concept are the questions of safety of the nuclear plant in case of fire and explosion hazards resulting from the leakage of flammable substances, the tolerable tritium contamination of the product hydrogen, or the situations of thermo-dynamic feedback in case of a loss of heat source (nuclear) or heat sink (chemical) resulting in thermal turbulences. A safety-related issue is the

Liquid hydrogen in Japan

Energy Technology Data Exchange (ETDEWEB)

Yasumi, S. [Iwatani Corp., Osaka (Japan). Dept. of Overseas Business Development

2009-07-01

Japan's Iwatani Corporation has focused its attention on hydrogen as the ultimate energy source in future. Unlike the United States, hydrogen use and delivery in liquid form is extremely limited in the European Union and in Japan. Iwatani Corporation broke through industry stereotypes by creating and building Hydro Edge Co. Ltd., Japan's largest liquid hydrogen plant. It was established in 2006 as a joint venture between Iwatani and Kansai Electric Power Group in Osaka. Hydro Edge is Japan's first combined liquid hydrogen and ASU plant, and is fully operational. Liquid oxygen, liquid nitrogen and liquid argon are separated from air using the cryogenic energy of liquefied natural gas fuel that is used for power generation. Liquid hydrogen is produced efficiently and simultaneously using liquid nitrogen. Approximately 12 times as much hydrogen in liquid form can be transported and supplied as pressurized hydrogen gas. This technology is a significant step forward in the dissemination and expansion of hydrogen in a hydrogen-based economy.

Status of hydrogen production by nuclear power

International Nuclear Information System (INIS)

Chang, Jong Wa; Yoo, Kun Joong; Park, Chang Kue

2001-07-01

Hydrogen production methods, such as electrolysis, thermochemical method, biological method, and photochemical method, are introduced in this report. Also reviewed are current status of the development of High Temperatrue Gas Coooled Reactor, and it application for hydrogen production

Super periodic potential

Science.gov (United States)

Hasan, Mohammd; Mandal, Bhabani Prasad

2018-04-01

In this paper we introduce the concept of super periodic potential (SPP) of arbitrary order n, n ∈I+, in one dimension. General theory of wave propagation through SPP of order n is presented and the reflection and transmission coefficients are derived in their closed analytical form by transfer matrix formulation. We present scattering features of super periodic rectangular potential and super periodic delta potential as special cases of SPP. It is found that the symmetric self-similarity is the special case of super periodicity. Thus by identifying a symmetric fractal potential as special cases of SPP, one can obtain the tunnelling amplitude for a particle from such fractal potential. By using the formalism of SPP we obtain the close form expression of tunnelling amplitude of a particle for general Cantor and Smith-Volterra-Cantor potentials.

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

International Nuclear Information System (INIS)

Kim, Jincheol; Kim, Taegyu

2015-01-01

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

Hydrogen and fuel cells: threat or opportunity to power company core business?

International Nuclear Information System (INIS)

Grant, A.

2004-01-01

'Full text:' It is noted that many utilities at this conference will discuss the problems with fuel cells (and the hydrogen economy) that revolve around interconnection of fuel cells as distributed generation resources. Interconnection details, both commercial and technical, are a major market barrier and a key problem for electric utilities as these technologies come to market. However, I would like to offer an opportunity to examine a broader subject area. Specifically, I would submit that one key issue is the need to look at the hydrogen and fuel cell market as a new opportunity for electric utilities. At BC Hydro we see that both the hydrogen market and the fuel cells market are potential threats and potential opportunities for our core business. We therefore believe it is prudent to learn more about these markets and 'learn by doing' by participating in demonstration projects with other partners where we can leverage our investments and spread the risk. In my talk I would like to explore the various elements of the BC Hydro fuel cell activities within this context of an evolving business model for a power utility. (author)

Hydrogen storage and integrated fuel cell assembly

Science.gov (United States)

Gross, Karl J.

2010-08-24

Hydrogen is stored in materials that absorb and desorb hydrogen with temperature dependent rates. A housing is provided that allows for the storage of one or more types of hydrogen-storage materials in close thermal proximity to a fuel cell stack. This arrangement, which includes alternating fuel cell stack and hydrogen-storage units, allows for close thermal matching of the hydrogen storage material and the fuel cell stack. Also, the present invention allows for tailoring of the hydrogen delivery by mixing different materials in one unit. Thermal insulation alternatively allows for a highly efficient unit. Individual power modules including one fuel cell stack surrounded by a pair of hydrogen-storage units allows for distribution of power throughout a vehicle or other electric power consuming devices.

Study of Super Dielectric Material for Novel Paradigm Capacitors

Science.gov (United States)

2018-03-01

density, power density, dielectric constant, constant current, constant voltage, electric field minimization, dipole 15. NUMBER OF PAGES 85 16. PRICE... Technology and Strategies for Improvement ..................................................................................6 4. Super Dielectric...ds infinitesimal displacement dt infinitesimal time DT discharge time dV infinitesimal voltage E electric field Etot total energy EC Lab

The energy carrier hydrogen

International Nuclear Information System (INIS)

Anon.

1992-01-01

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

Process of super-black shading material applied to the star sensor based on Ni-P alloys

Science.gov (United States)

Liu, Fengdeng; Xing, Fei; Wu, Yuelong; You, Zheng

2014-12-01

Super-black materials based on Nanotechnology have very important applications in many science fields. Super-black materials which have been reported currently, although have excellent light-trapping properties, most of them need the use of sophisticated equipment , the long-time synthesis , high temperature environment and release flammable, explosive and other dangerous gases. So many kinds of problems have hindered the application of such super-black material in practice. This project had nano super-black material developed with simple equipment and process, instead of complicated and dangerous process steps in high temperature and high pressure. On the basis of literature research, we successfully worked out a set of large-area Ni-P alloy plating method through a series of experiments exploring and analyze the experimental results. In the condition of the above Ni-P alloy, we took the solution, which anodized the Ni-P alloy immersed in the non-oxidizing acid, instead of conventional blackening process. It`s a big break for changing the situation in which oxidation, corrosion, vigorous evolution of hydrogen gas in the process are performed at the same location. As a result, not only the reaction process decreased sensitivity to time error, but also the position of the bubble layer no longer located in the surface of the workpiece which may impede observing the process of reaction. Consequently, the solution improved the controllability of the blackening process. In addition, we conducted the research of nano super-black material, exploring nano-super-black material in terms of space optical sensor.

California-Specific Power-to-Hydrogen and Power-to-Gas Business Case Evaluation

Energy Technology Data Exchange (ETDEWEB)

Eichman, Joshua D. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Flores-Espino, Francisco [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2018-02-12

Flexible operation of electrolysis systems represents an opportunity to reduce the cost of hydrogen for a variety of end-uses while also supporting grid operations and thereby enabling greater renewable penetration. California is an ideal location to realize that value on account of growing renewable capacity and markets for hydrogen as a fuel cell electric vehicle (FCEV) fuel, refineries, and other end-uses. Shifting the production of hydrogen to avoid high cost electricity and participation in utility and system operator markets along with installing renewable generation to avoid utility charges and increase revenue from the Low Carbon Fuel Standard (LCFS) program can result in around $2.5/kg (21%) reduction in the production and delivery cost of hydrogen from electrolysis. This reduction can be achieved without impacting the consumers of hydrogen. Additionally, future strategies for reducing hydrogen cost were explored and include lower cost of capital, participation in the Renewable Fuel Standard program, capital cost reduction, and increased LCFS value. Each must be achieved independently and could each contribute to further reductions. Using the assumptions in this study found a 29% reduction in cost if all future strategies are realized. Flexible hydrogen production can simultaneously improve the performance and decarbonize multiple energy sectors. The lessons learned from this study should be used to understand near-term cost drivers and to support longer-term research activities to further improve cost effectiveness of grid integrated electrolysis systems.

Frames in super Hilbert modules

Directory of Open Access Journals (Sweden)

Mehdi Rashidi-Kouchi

2018-01-01

Full Text Available In this paper, we define super Hilbert module and investigate frames in this space. Super Hilbert modules are  generalization of super Hilbert spaces in Hilbert C*-module setting. Also, we define frames in a super Hilbert module and characterize them by using of the concept of g-frames in a Hilbert C*-module. Finally, disjoint frames in Hilbert C*-modules are introduced and investigated.

SuperB: A High-Luminosity Asymmetric e+e- Super Flavor Factory

Energy Technology Data Exchange (ETDEWEB)

Bona, M.; /et al.

2007-05-18

We discuss herein the exciting physics program that can be accomplished with a very large sample of heavy quark and heavy lepton decays produced in the very clean environment of an e{sup +}e{sup -} collider; a program complementary to that of an experiment such as LHCb at a hadronic machine. It then presents the conceptual design of a new type of e{sup +}e{sup -} collider that produces a nearly two-order-of-magnitude increase in luminosity over the current generation of asymmetric B Factories. The key idea is the use of low emittance beams produced in an accelerator lattice derived from the ILC Damping Ring Design, together with a new collision region, again with roots in the ILC final focus design, but with important new concepts developed in this design effort. Remarkably, SuperB produces this very large improvement in luminosity with circulating currents and wallplug power similar to those of the current B Factories. There is clear synergy with ILC R&D; design efforts have already influenced one another, and many aspects of the ILC Damping Rings and Final Focus would be operationally tested at SuperB. Finally, the design of an appropriate detector, based on an upgrade of BABAR as an example, is discussed in some detail. A preliminary cost estimate is presented, as is an example construction timeline.

Hydrogen millennium

International Nuclear Information System (INIS)

Bose, T.K.; Benard, P.

2000-05-01

The 10th Canadian Hydrogen Conference was held at the Hilton Hotel in Quebec City from May 28 to May 31, 2000. The topics discussed included current drivers for the hydrogen economy, the international response to these drivers, new initiatives, sustainable as well as biological and hydrocarbon-derived production of hydrogen, defense applications of fuel cells, hydrogen storage on metal hydrides and carbon nanostructures, stationary power and remote application, micro-fuel cells and portable applications, marketing aspects, fuel cell modeling, materials, safety, fuel cell vehicles and residential applications. (author)

Very High Efficiency Reactor (VHER) Concepts for Electrical Power Generation and Hydrogen Production

International Nuclear Information System (INIS)

PARMA JR, EDWARD J.; PICKARD, PAUL S.; SUO-ANTTILA, AHTI JORMA

2003-01-01

The goal of the Very High Efficiency Reactor study was to develop and analyze concepts for the next generation of nuclear power reactors. The next generation power reactor should be cost effective compared to current power generation plant, passively safe, and proliferation-resistant. High-temperature reactor systems allow higher electrical generating efficiencies and high-temperature process heat applications, such as thermo-chemical hydrogen production. The study focused on three concepts; one using molten salt coolant with a prismatic fuel-element geometry, the other two using high-pressure helium coolant with a prismatic fuel-element geometry and a fuel-pebble element design. Peak operating temperatures, passive-safety, decay heat removal, criticality, burnup, reactivity coefficients, and material issues were analyzed to determine the technical feasibility of each concept

Improving long-term operation of power sources in off-grid hybrid systems based on renewable energy, hydrogen and battery

Science.gov (United States)

García, Pablo; Torreglosa, Juan P.; Fernández, Luis M.; Jurado, Francisco

2014-11-01

This paper presents two novel hourly energy supervisory controls (ESC) for improving long-term operation of off-grid hybrid systems (HS) integrating renewable energy sources (wind turbine and photovoltaic solar panels), hydrogen system (fuel cell, hydrogen tank and electrolyzer) and battery. The first ESC tries to improve the power supplied by the HS and the power stored in the battery and/or in the hydrogen tank, whereas the second one tries to minimize the number of needed elements (batteries, fuel cells and electrolyzers) throughout the expected life of the HS (25 years). Moreover, in both ESC, the battery state-of-charge (SOC) and the hydrogen tank level are controlled and maintained between optimum operating margins. Finally, a comparative study between the controls is carried out by models of the commercially available components used in the HS under study in this work. These ESC are also compared with a third ESC, already published by the authors, and based on reducing the utilization costs of the energy storage devices. The comparative study proves the right performance of the ESC and their differences.

Hydrogen & fuel cells: advances in transportation and power

National Research Council Canada - National Science Library

Hordeski, Michael F

2009-01-01

... race, it became more of an economics issue since as long as petroleum was available and cheap there was no need to develop a hydrogen technology. Now, we see much more investment in fuel cell technology, hydrogen fueled vehicles and even hydrogen fuel stations. The technology is being pushed by economics as oil prices continue to rise with dwind...

Safety characteristics of hydrogen at super ambient conditions: lubricant contamination influencing the auto ignition temperature

International Nuclear Information System (INIS)

Liebner, C.; Schroder, V.; Holtappels, K.

2006-01-01

Inventing hydrogen as a commonly used future energy carrier the long term social acceptance as well as the clean energy image strongly depends upon the safety of its applications. The safety characteristics of hydrogen build a special challenge e.g. in the field of combustion engine development. Small impurities from lubricants used in motors and pumps, may serve as radical source, strongly influencing the auto ignition temperature of hydrogen. Auto Ignition Temperature (AIT) of Hydrogen-Air mixtures were measured in closed autoclaves made from stainless steel, similar to the closed bomb method described in the European standard EN 1839. Initial pressures of 10 bar(a) and 30 bar(a) of a premixed stoichiometric hydrogen-air mixture were investigated. Auto ignition can be obtained about 100 K below the standard AIT (560 deg C, atmospheric pressure) and 300 K below the standard AIT when contaminated through motor oil. (authors)

Aberrations and adaptive optics in super-resolution microscopy

Science.gov (United States)

Booth, Martin; Andrade, Débora; Burke, Daniel; Patton, Brian; Zurauskas, Mantas

2015-01-01

As one of the most powerful tools in the biological investigation of cellular structures and dynamic processes, fluorescence microscopy has undergone extraordinary developments in the past decades. The advent of super-resolution techniques has enabled fluorescence microscopy – or rather nanoscopy – to achieve nanoscale resolution in living specimens and unravelled the interior of cells with unprecedented detail. The methods employed in this expanding field of microscopy, however, are especially prone to the detrimental effects of optical aberrations. In this review, we discuss how super-resolution microscopy techniques based upon single-molecule switching, stimulated emission depletion and structured illumination each suffer from aberrations in different ways that are dependent upon intrinsic technical aspects. We discuss the use of adaptive optics as an effective means to overcome this problem. PMID:26124194

Some aspects of the development of hydrogen power engineering and technology

Energy Technology Data Exchange (ETDEWEB)

Shpil' rayn, E E; Malyshenko, S P

1980-01-01

In the USSR, FRG, United States, Japan, France, Italy and other countries, broad programs of research and development have been adopted in the area of hydrogen power engineering. Broad and multifaceted development of hydrogen power engineering and technology is expected in no earlier than the first quarter of the twenty-first century. However, the rise in prices for liquid and gaseous fuel and the rise in demand for H/sub 2/ of its traditional consumers can make it expedient to develop large-scale production of H/sub 2/ and gradual displacement of natural liquid and gaseous fuels from the processes of oil refining, synthesis of methanol and ammonia, metallurgical production of nuclear fuel and coal even before the end of the twentieth century. A natural system of energy source-production block for obtaining the energy carrier (H/sub 2/) can make it possible in the last quarter of the twentieth century to solve the problems associated with creating large autonomous energy-technological complexes which do not require hydrocarbon fuel for production of energy and products of chemical synthesis, oil refining, metallurgy and others. In this sense, even now the question must be solved of creating energy-technology which uses as the main energy resources nuclear energy and coal, as well as energy-carrier and raw material, H/sub 2/ and artificial fuels on its basis. In addition, development of large energy systems based on nuclear energy and coal as the energy sources and which include different-characteristic and numerous consumers results in the need already in the near future to use artificial fuels based on H/sub 2/ and H/sub 2/ in power engineering as the energy carriers and energy accumulators. This will make it possible to construct a more flexible system adapted to the consumers which does not depend on the type of energy sources.

Institute for Sustained Performance, Energy, and Resilience (SuPER)

Energy Technology Data Exchange (ETDEWEB)

Jagode, Heike [Univ. of Tennessee, Knoxville, TN (United States); Bosilca, George [Univ. of Tennessee, Knoxville, TN (United States); Danalis, Anthony [Univ. of Tennessee, Knoxville, TN (United States); Dongarra, Jack [Univ. of Tennessee, Knoxville, TN (United States); Moore, Shirley [Univ. of Texas, El Paso, TX (United States)

2016-11-30

The University of Tennessee (UTK) and University of Texas at El Paso (UTEP) partnership supported the three main thrusts of the SUPER project---performance, energy, and resilience. The UTK-UTEP effort thus helped advance the main goal of SUPER, which was to ensure that DOE's computational scientists can successfully exploit the emerging generation of high performance computing (HPC) systems. This goal is being met by providing application scientists with strategies and tools to productively maximize performance, conserve energy, and attain resilience. The primary vehicle through which UTK provided performance measurement support to SUPER and the larger HPC community is the Performance Application Programming Interface (PAPI). PAPI is an ongoing project that provides a consistent interface and methodology for collecting hardware performance information from various hardware and software components, including most major CPUs, GPUs and accelerators, interconnects, I/O systems, and power interfaces, as well as virtual cloud environments. The PAPI software is widely used for performance modeling of scientific and engineering applications---for example, the HOMME (High Order Methods Modeling Environment) climate code, and the GAMESS and NWChem computational chemistry codes---on DOE supercomputers. PAPI is widely deployed as middleware for use by higher-level profiling, tracing, and sampling tools (e.g., CrayPat, HPCToolkit, Scalasca, Score-P, TAU, Vampir, PerfExpert), making it the de facto standard for hardware counter analysis. PAPI has established itself as fundamental software infrastructure in every application domain (spanning academia, government, and industry), where improving performance can be mission critical. Ultimately, as more application scientists migrate their applications to HPC platforms, they will benefit from the extended capabilities this grant brought to PAPI to analyze and optimize performance in these environments, whether they use PAPI

Beyond the Cold-War Reprise of the Arctic Super-Powers. Decoding the Structural Meaning of the Ukrainian Crisis

Directory of Open Access Journals (Sweden)

John McMurtry

2015-03-01

Full Text Available The “Ukraine crisis” repeats a script as old as the Cold War, of which the Arctic was one of its main theatres and that, as suggested by Irina Zhilina in her 2013 study about NATO in the far north for issue 8(1 of Nordicum-Mediterraneum, could regain such a role, were frictions between East and West to resurface. And they have resurfaced. The ongoing Cold-War-like narrative vis-à-vis Ukraine features rising attacks by corporate states and media on the traditional whipping boy of Russia. As usual, “escalating the crisis” is the other Arctic super-power: the US. As usual, alarm about “increasing lawless aggression” is projection of US policy itself.

Hydrogen generation comparison between lead-calcium and lead-antimony batteries in nuclear power plant

International Nuclear Information System (INIS)

Zhao Hongjun; Qi Suoni; Shen Yan; Li Jia

2014-01-01

Battery type selection is performed with the help of technical information supplied by vendors, and according to relevant criteria. Analysis and comparison of the hydrogen generation differences between two different lead-acid battery types are carried out through calculation. The analysis result may provide suggestions for battery type selection in nuclear power plant. (authors)

Integration of direct carbon and hydrogen fuel cells for highly efficient power generation from hydrocarbon fuels

Energy Technology Data Exchange (ETDEWEB)

Muradov, Nazim; Choi, Pyoungho; Smith, Franklyn; Bokerman, Gary [Florida Solar Energy Center, University of Central Florida, 1679 Clearlake Road, Cocoa, FL 32922-5703 (United States)

2010-02-15

In view of impending depletion of hydrocarbon fuel resources and their negative environmental impact, it is imperative to significantly increase the energy conversion efficiency of hydrocarbon-based power generation systems. The combination of a hydrocarbon decomposition reactor with a direct carbon and hydrogen fuel cells (FC) as a means for a significant increase in chemical-to-electrical energy conversion efficiency is discussed in this paper. The data on development and operation of a thermocatalytic hydrocarbon decomposition reactor and its coupling with a proton exchange membrane FC are presented. The analysis of the integrated power generating system including a hydrocarbon decomposition reactor, direct carbon and hydrogen FC using natural gas and propane as fuels is conducted. It was estimated that overall chemical-to-electrical energy conversion efficiency of the integrated system varied in the range of 49.4-82.5%, depending on the type of fuel and FC used, and CO{sub 2} emission per kW{sub el}h produced is less than half of that from conventional power generation sources. (author)

Mitigation of hydrogen hazards in water cooled power reactors

International Nuclear Information System (INIS)

2001-02-01

Past considerations of hydrogen generated in containment buildings have tended to focus attention on design basis accidents (DBAs) where the extent of the in-core metal-water reaction is limited at low values by the operation of the emergency core cooling systems (ECCS). The radiolysis of water in the core and in the containment sump, together with the possible corrosion of metals and paints in the containment, are all relatively slow processes. Therefore, in DBAs the time scale involved for the generation of hydrogen allows sufficient time for initiation of measures to control the amount of hydrogen in the containment atmosphere and to prevent any burning. Provisions have been made in most plants to keep the local hydrogen concentration below its flammability limit (4% of volume) by means of mixing devices and thermal recombiners. Severe accidents, involving large scale core degradation and possibly even core concrete interactions, raise the possibility of hydrogen release rates greatly exceeding the capacity of conventional DBA hydrogen control measures. The accident at Three Mile Island illustrated the potential of unmitigated hydrogen accumulation to escalate the potential consequences of a severe accident. In a severe accident scenario, local high hydrogen concentrations can be reached in a short time, leading to flammable gas mixtures in containment. Another possibility is that local high steam concentrations will initially create an inert atmosphere and prevent burning for a limited time. While such temporary inerting provides additional time for mixing (dilution) of the hydrogen with containment air, depending on the quantity of hydrogen released, it prevents early intervention by deliberate ignition and sets up conditions for more severe combustion hazards after steam condensation eventually occurs, e.g., by spray initiation or the long term cooling down of the containment atmosphere. As the foregoing example indicates, analysis of the hydrogen threat in

Hydrogen Storage for Aircraft Applications Overview

Science.gov (United States)

Colozza, Anthony J.; Kohout, Lisa (Technical Monitor)

2002-01-01

Advances in fuel cell technology have brought about their consideration as sources of power for aircraft. This power can be utilized to run aircraft systems or even provide propulsion power. One of the key obstacles to utilizing fuel cells on aircraft is the storage of hydrogen. An overview of the potential methods of hydrogen storage was compiled. This overview identifies various methods of hydrogen storage and points out their advantages and disadvantages relative to aircraft applications. Minimizing weight and volume are the key aspects to storing hydrogen within an aircraft. An analysis was performed to show how changes in certain parameters of a given storage system affect its mass and volume.

(Super Variable Costing-Throughput Costing)

OpenAIRE

Çakıcı, Cemal

2006-01-01

(Super Variable Costing-Throughput Costing) The aim of this study is to explain the super-variable costing method which is a new subject in cost and management accounting and to show it’s working practicly.Shortly, super-variable costing can be defined as a costing method which is use only direct material costs in calculate of product costs and treats all costs except these (direct labor and overhead) as periad costs or operating costs.By using super-variable costing method, product costs ar...

Storage the electric power: yes, it is indispensable and it is possible. Why, where, how; Stocker l'electricite: oui, c'est indispensable, et c'est possible. Pourquoi, ou, comment

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

This document describes the main characteristics of various electric power storage methods and their application domains. The large-scale storages include the hydraulic systems, those using compressed air, the batteries or those implementing a thermal way. The small-scale storages are electrochemical as the accumulators, the super-capacitors, mechanical as the flywheel, magnetic or also by the hydrogen use. The first part presents the necessity of the electric power storage, the second part the places of these storage. The third part details the forms of storage. (A.L.B.)

The car on hydrogen: problems and solutions

International Nuclear Information System (INIS)

Koroteev, A.S.; Smolyarov, V.A.

2004-01-01

Development of the hydrogen power for transformation of the most power-consumption branch of the industry and transport into new power source - hydrogen as strategy direction for the reduction of pollution of environment and deficit of oil motor fuel is considered. On the basis of comparison of different type of electrochemical generators conclusion on advantages of electrochemical generator with solid polymer membrane was made. Different systems of hydrogen storage in automobile are considered. The system of the gaseous hydrogen storage at high pressure in cistern from composite materials is the most promise [ru

Hydrogen-Enhanced Lunar Oxygen Extraction and Storage Using Only Solar Power

Science.gov (United States)

Burton, rodney; King, Darren

2013-01-01

The innovation consists of a thermodynamic system for extracting in situ oxygen vapor from lunar regolith using a solar photovoltaic power source in a reactor, a method for thermally insulating the reactor, a method for protecting the reactor internal components from oxidation by the extracted oxygen, a method for removing unwanted chemical species produced in the reactor from the oxygen vapor, a method for passively storing the oxygen, and a method for releasing high-purity oxygen from storage for lunar use. Lunar oxygen exists in various types of minerals, mostly silicates. The energy required to extract the oxygen from the minerals is 30 to 60 MJ/kg O. Using simple heating, the extraction rate depends on temperature. The minimum temperature is approximately 2,500 K, which is at the upper end of available oven temperatures. The oxygen is released from storage in a purified state, as needed, especially if for human consumption. This method extracts oxygen from regolith by treating the problem as a closed batch cycle system. The innovation works equally well in Earth or Lunar gravity fields, at low partial pressure of oxygen, and makes use of in situ regolith for system insulation. The innovation extracts oxygen from lunar regolith using a method similar to vacuum pyrolysis, but with hydrogen cover gas added stoichiometrically to react with the oxygen as it is produced by radiatively heating regolith to 2,500 K. The hydrogen flows over and through the heating element (HE), protecting it from released oxygen. The H2 O2 heat of reaction is regeneratively recovered to assist the heating process. Lunar regolith is loaded into a large-diameter, low-height pancake reactor powered by photovoltaic cells. The reactor lid contains a 2,500 K HE that radiates downward onto the regolith to heat it and extract oxygen, and is shielded above by a multi-layer tungsten radiation shield. Hydrogen cover gas percolates through the perforated tungsten shielding and HE, preventing

A SUPER-CONDUCTING LINAC DRIVER FOR THE HFBR.

Energy Technology Data Exchange (ETDEWEB)

Alessi, J.; Raparia, D.; Ruggiero, A.G.

2000-08-21

This paper reports on the feasibility study of a proton Super-Conducting Linac (SCL) as a driver for the High-Flux Breeder Reactor (HFBR) at Brookhaven National Laboratory (BNL). The Linac operates in Continuous Wave (CW) mode to produce an average 10 MW of beam power. The Linac beam energy is 1.0 GeV. The average proton beam intensity in exit is 10 mA.

Towards an Ultrasonic Guided Wave Procedure for Health Monitoring of Composite Vessels: Application to Hydrogen-Powered Aircraft.

Science.gov (United States)

Yaacoubi, Slah; McKeon, Peter; Ke, Weina; Declercq, Nico F; Dahmene, Fethi

2017-09-19

This paper presents an overview and description of the approach to be used to investigate the behavior and the defect sensitivity of various ultrasonic guided wave (UGW) modes propagating specifically in composite cylindrical vessels in the framework of the safety of hydrogen energy transportation such as hydrogen-powered aircrafts. These structures which consist of thick and multi-layer composites are envisioned for housing hydrogen gas at high pressures. Due to safety concerns associated with a weakened structure, structural health monitoring techniques are needed. A procedure for optimizing damage detection in these structural types is presented. It is shown that a finite element method can help identify useful experimental parameters including frequency range, excitation type, and receiver placement.

Electrically tuned super-capacitors

OpenAIRE

Chowdhury, Tazima S.; Grebel, Haim

2015-01-01

Fast charging and discharging of large amounts of electrical energy make super-capacitors ideal for short-term energy storage [1-5]. In its simplest form, the super-capacitor is an electrolytic capacitor made of an anode and a cathode immersed in an electrolyte. As for an ordinary capacitor, minimizing the charge separation distance and increasing the electrode area increase capacitance. In super-capacitors, charge separation is of nano-meter scale at each of the electrode interface (the Helm...

Example-Based Super-Resolution Fluorescence Microscopy.

Science.gov (United States)

Jia, Shu; Han, Boran; Kutz, J Nathan

2018-04-23

Capturing biological dynamics with high spatiotemporal resolution demands the advancement in imaging technologies. Super-resolution fluorescence microscopy offers spatial resolution surpassing the diffraction limit to resolve near-molecular-level details. While various strategies have been reported to improve the temporal resolution of super-resolution imaging, all super-resolution techniques are still fundamentally limited by the trade-off associated with the longer image acquisition time that is needed to achieve higher spatial information. Here, we demonstrated an example-based, computational method that aims to obtain super-resolution images using conventional imaging without increasing the imaging time. With a low-resolution image input, the method provides an estimate of its super-resolution image based on an example database that contains super- and low-resolution image pairs of biological structures of interest. The computational imaging of cellular microtubules agrees approximately with the experimental super-resolution STORM results. This new approach may offer potential improvements in temporal resolution for experimental super-resolution fluorescence microscopy and provide a new path for large-data aided biomedical imaging.

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

International Nuclear Information System (INIS)

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

2005-01-01

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

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

Science.gov (United States)

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

2014-11-18

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

Nuclear electrolytic hydrogen

International Nuclear Information System (INIS)

Barnstaple, A.G.; Petrella, A.J.

1982-05-01

An extensive study of hydrogen supply has recently been carried out by Ontario Hydro which indicates that electrolytic hydrogen produced from nuclear electricity could offer the lowest cost option for any future large scale hydrogen supply in the Province of Ontario, Canada. This paper provides a synopsis of the Ontario Hydro study, a brief overview of the economic factors supporting the study conclusion and discussion of a number of issues concerning the supply of electrolytic hydrogen by electric power utilities

Super long-term scenario of world nuclear power generation and uranium supply and demand until 2030 and further 2100

International Nuclear Information System (INIS)

Komiyama, Ryoichi; Kakinoki, Tatsuro

2007-01-01

Based on latest nuclear policy and development trend in each country in the world, quantity of nuclear power generation and the uranium supply and demand until 2030 and further 2100 were predicted. As a result, the introduction of nuclear power stations spreads around Asia until 2030. The limitation on the uranium resources clearly does not exist until 2030, but a development period of around 10 years is necessary for exploitation of uranium resources. If timely development investment does not advance, it may invite shortage of uranium supply and promote a remarkable rise of uranium supply price. If the reinforcement of the anti-global warming measure and the diversification of the energy source advance at the super long-term time span called 2100, the world coal power largely decreases and the introduction of the nuclear power enlarges steadily. Introduction of the light water reactor (LWR) extends until 2080 since the fuel uses uranium resources of about 70 year ratio of reserves to production, but quantity of LWR power stations and power generation changes for the decrease due to the limitation of uranium resources after it. On the other hand, sustained expansion of the plutonium utilization by the fuel cycle technology and the introduction of the fast breeder reactor (FBR) advance after 2050. Then the sustained expansion of nuclear power is surely expected to occupy the first share of power generation in 2100. On this account it is necessary to push forward the plutonium use, backend technology and FBR development globally, and Japan is expected to carry a positive role to lead international nuclear energy technology development as a nuclear energy developed nation. (T. Tanaka)

Development of Advanced Small Hydrogen Engines

Energy Technology Data Exchange (ETDEWEB)

Sapru, Krishna; Tan, Zhaosheng; Chao, Ben

2010-09-30

The main objective of the project is to develop advanced, low cost conversions of small (< 25 hp) gasoline internal combustion engines (ICEs) to run on hydrogen fuel while maintaining the same performance and durability. This final technical report summarizes the results of i) the details of the conversion of several small gasoline ICEs to run on hydrogen, ii) the durability test of a converted hydrogen engine and iii) the demonstration of a prototype bundled canister solid hydrogen storage system. Peak power of the hydrogen engine achieves 60% of the power output of the gasoline counterpart. The efforts to boost the engine power with various options including installing the over-sized turbocharger, retrofit of custom-made pistons with high compression ratio, an advanced ignition system, and various types of fuel injection systems are not realized. A converted Honda GC160 engine with ACS system to run with hydrogen fuel is successful. Total accumulative runtime is 785 hours. A prototype bundled canister solid hydrogen storage system having nominal capacity of 1.2 kg is designed, constructed and demonstrated. It is capable of supporting a wide range of output load of a hydrogen generator.

The mid-latitude ionosphere under quiet geomagnetic conditions: propagation analysis of SuperDARN radar observations from large ionospheric perturbations

OpenAIRE

De Larquier, Sebastien

2013-01-01

The Earth's ionosphere is a dynamic environment strongly coupled to the neutral atmosphere, magnetosphere and solar activity. In the context of this research, we restrict our interest to the mid-latitude (a.k.a., sub-auroral) ionosphere during quiet geomagnetic conditions. The Super Dual Auroral Radar Network (SuperDARN) is composed of more than 30 low-power High Frequency (HF, from 8-18 MHz) Doppler radars covering the sub-auroral, auroral and polar ionosphere in both hemispheres. SuperDARN ...

Handbook of Super 8 Production.

Science.gov (United States)

Telzer, Ronnie, Ed.

This handbook is designed for anyone interested in producing super 8 films at any level of complexity and cost. Separate chapters present detailed discussions of the following topics: super 8 production systems and super 8 shooting and editing systems; budgeting; cinematography and sound recording; preparing to edit; editing; mixing sound tracks;…

Vacuum technology issues for the SSC [Superconducting Super Collider

International Nuclear Information System (INIS)

Joestlein, H.

1989-01-01

The Superconducting Super Collider, to be built in Texas, will provide an energy of 40 TeV from colliding proton beams. This energy is twenty times higher than currently available from the only other cryogenic collider, the Fermilab Tevatron, and will allow experiments that can lead to a better understanding of the fundamental properties of matter. The energy scale and the size of the new machine pose intriguing challenges and opportunities for the its vacuum systems. The discussion will include the effects of synchrotron radiation on cryogenic beam tubes, cold adsorption pumps for hydrogen, methods of leak checking large cryogenic systems, the development of cold beam valves, and radiation damage to components, especially electronics. 9 figs., 1 tab

Hydrogen fuel - Universal energy

Science.gov (United States)

Prince, A. G.; Burg, J. A.

The technology for the production, storage, transmission, and consumption of hydrogen as a fuel is surveyed, with the physical and chemical properties of hydrogen examined as they affect its use as a fuel. Sources of hydrogen production are described including synthesis from coal or natural gas, biomass conversion, thermochemical decomposition of water, and electrolysis of water, of these only electrolysis is considered economicially and technologically feasible in the near future. Methods of production of the large quantities of electricity required for the electrolysis of sea water are explored: fossil fuels, hydroelectric plants, nuclear fission, solar energy, wind power, geothermal energy, tidal power, wave motion, electrochemical concentration cells, and finally ocean thermal energy conversion (OTEC). The wind power and OTEC are considered in detail as the most feasible approaches. Techniques for transmission (by railcar or pipeline), storage (as liquid in underwater or underground tanks, as granular metal hydride, or as cryogenic liquid), and consumption (in fuel cells in conventional power plants, for home usage, for industrial furnaces, and for cars and aircraft) are analyzed. The safety problems of hydrogen as a universal fuel are discussed, noting that they are no greater than those for conventional fuels.

Solar hydrogen for urban trucks

Energy Technology Data Exchange (ETDEWEB)

Provenzano, J.: Scott, P.B.; Zweig, R. [Clean Air Now, Northridge, CA (United States)

1997-12-31

The Clean Air Now (CAN) Solar Hydrogen Project, located at Xerox Corp., El Segundo, California, includes solar photovoltaic powered hydrogen generation, compression, storage and end use. Three modified Ford Ranger trucks use the hydrogen fuel. The stand-alone electrolyzer and hydrogen dispensing system are solely powered by a photovoltaic array. A variable frequency DC-AC converter steps up the voltage to drive the 15 horsepower compressor motor. On site storage is available for up to 14,000 standard cubic feet (SCF) of solar hydrogen, and up to 80,000 SCF of commercial hydrogen. The project is 3 miles from Los Angeles International airport. The engine conversions are bored to 2.9 liter displacement and are supercharged. Performance is similar to that of the Ranger gasoline powered truck. Fuel is stored in carbon composite tanks (just behind the driver`s cab) at pressures up to 3600 psi. Truck range is 144 miles, given 3600 psi of hydrogen. The engine operates in lean burn mode, with nil CO and HC emissions. NO{sub x} emissions vary with load and rpm in the range from 10 to 100 ppm, yielding total emissions at a small fraction of the ULEV standard. Two trucks have been converted for the Xerox fleet, and one for the City of West Hollywood. A public outreach program, done in conjunction with the local public schools and the Department of Energy, introduces the local public to the advantages of hydrogen fuel technologies. The Clean Air Now program demonstrates that hydrogen powered fleet development is an appropriate, safe, and effective strategy for improvement of urban air quality, energy security and avoidance of global warming impact. Continued technology development and cost reduction promises to make such implementation market competitive.

The super-resolution debate

Science.gov (United States)

Won, Rachel

2018-05-01

In the quest for nanoscopy with super-resolution, consensus from the imaging community is that super-resolution is not always needed and that scientists should choose an imaging technique based on their specific application.

Meeting the near-term demand for hydrogen using nuclear energy in competitive power markets

International Nuclear Information System (INIS)

Miller, Alistair I.; Duffey, Romney B.

2004-01-01

Hydrogen is becoming the reference fuel for future transportation and, in the USA in particular, a vision for its production from advanced nuclear reactors has been formulated. Fulfillment of this vision depend on its economics in 2020 or later. Prior to 2020, hydrogen needs to gain a substantial foothold without incurring excessive costs for the establishment of the distribution network for the new fuel. Water electrolysis and steam-methane reforming (SMR) are the existing hydrogen-production technologies, used for small-scale and large-scale production, respectively. Provided electricity is produced at costs expected for nuclear reactors of near-term design, electrolysis appears to offer superior economics when the SMR-related costs of distribution and sequestration (or an equivalent emission levy) are included. This is shown to hold at least until several percentage points of road transport have been converted to hydrogen. Electrolysis has large advantages over SMRs in being almost scale-independent and allowing local production. The key requirements for affordable electrolysis are low capital cost and relatively high utilization, although the paper shows that it should be advantageous to avoid the peaks of electricity demand and cost. The electricity source must enable high utilization as well as being itself low-cost and emissions-free. By using off-peak electricity, no extra costs for enhanced electricity distribution should occur. The longer-term supply of hydrogen may ultimately evolve away from low-temperature water electrolysis but it appears to be an excellent technology for early deployment and capable of supplying hydrogen at prices not dissimilar from today's costs for gasoline and diesel provided the vehicle's power unit is a fuel cell. (author)

Hydrogen isotope separation for fusion power applications

Energy Technology Data Exchange (ETDEWEB)

Smith, R., E-mail: robert.smith@ccfe.ac.uk [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); JET-EFDA, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); Whittaker, D.A.J.; Butler, B.; Hollingsworth, A.; Lawless, R.E.; Lefebvre, X.; Medley, S.A.; Parracho, A.I.; Wakeling, B. [EURATOM/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom); JET-EFDA, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

2015-10-05

Highlights: • Summary of the tritium plant, the Active Gas Handling System (AGHS), at JET. • Review of the Water Detritiation System (WDS) under construction. • Design of the new Material Detritiation Facility (MDF). • Review of problems in fusion related to metal/hydrogen system. - Abstract: The invited talk given at MH2014 in Salford ranged over many issues associated with hydrogen isotope separation, fusion machines and the hydrogen/metal systems found in the Joint European Torus (JET) machine located near Oxford. As this sort of talk does not lend itself well to a paper below I have attempted to highlight some of the more pertinent information. After a description of the Active Gas Handling System (AGHS) a brief summary of isotope separation systems is described followed by descriptions of three major projects currently being undertaken by the Tritium Engineering and Science Group (TESG), the upgrade to the Analytical Systems (AN-GC) at the AGH, the construction of a Water Detritiation System (WDS) and a Material Detritiation Facility (MDF). Finally, a review of some of the challenges facing fusion with respect to metal/hydrogen systems is presented.

Usage of super high speed computer for clarification of complex phenomena

International Nuclear Information System (INIS)

Sekiguchi, Tomotsugu; Sato, Mitsuhisa; Nakata, Hideki; Tatebe, Osami; Takagi, Hiromitsu

1999-01-01

This study aims at construction of an efficient super high speed computer system application environment in response to parallel distributed system with easy transplantation to different computer system and different number by conducting research and development on super high speed computer application technology required for elucidation of complicated phenomenon in elucidation of complicated phenomenon of nuclear power field due to computed scientific method. In order to realize such environment, the Electrotechnical Laboratory has conducted development on Ninf, a network numerical information library. This Ninf system can supply a global network infrastructure for worldwide computing with high performance on further wide range distributed network (G.K.)

Investigation and analysis of hydrogen ignition and explosion events in foreign nuclear power plants

Energy Technology Data Exchange (ETDEWEB)

Okuda, Yasunori [Institute of Nuclear Safety System, Inc., Mihama, Fukui (Japan)

2002-09-01

Reports about hydrogen ignition and explosion events in foreign nuclear power plants from 1980 to 2001 were investigated, and 31 events were identified. Analysis showed that they were categorized in (1) outer leakage ignition events and (2) inner accumulation ignition events. The dominant event for PWR (pressurized water reactor) was outer leakage ignition in the main generator, and in BWR (boiling water reactor) it was inner accumulation ignition in the off-gas system. The outer leakage ignition was a result of work process failure with the ignition source, operator error, or main generator hydrogen leakage. The inner accumulation ignition events were caused by equipment failure or insufficient monitoring. With careful preventive measures, the factors leading to these events could be eliminated. (author)

Super VHS video cassette recorder, A-SB88; Super VHS video A-SB88

Energy Technology Data Exchange (ETDEWEB)

NONE

1999-03-01

A super VHS video cassette recorder, A-SB88, was commercialized having no compromised aspects at all in picture quality, sound quality, operability, energy conservation, design, etc. In the picture quality, the VCR is mounted with the S-ET system capable of realizing a quality comparable to SVHS with a three-dimensional Y/C detached circuit for dynamic moving image detection, three-dimensional DNR(digital noise reduction) and TBC(time base corrector), FE(flying erase) circuit, and a normal tape. In the operability, it is provided with a remote control transfer in large LCD, 400x high speed rewind, reservation system capable of simply reserving a serial drama for example, and a function for searching the end of picture recording; also, in the environmental aspect, the stand-by power consumption was reduced to 1/10 of conventional models (ratio with Toshiba A-BS6 at display power off). (translated by NEDO)

SuperMAG: Present and Future Capabilities

Science.gov (United States)

Hsieh, S. W.; Gjerloev, J. W.; Barnes, R. J.

2009-12-01

SuperMAG is a global collaboration that provides ground magnetic field perturbations from a long list of stations in the same coordinate system, identical time resolution and with a common baseline removal approach. This unique high quality dataset provides a continuous and nearly global monitoring of the ground magnetic field perturbation. Currently, only archived data are available on the website and hence it targets basic research without any operational capabilities. The existing SuperMAG software can be easily adapted to ingest real-time or near real-time data and provide a now-casting capability. The SuperDARN program has a long history of providing near real-time maps of the northern hemisphere electrostatic potential and as both SuperMAG and SuperDARN share common software it is relatively easy to adapt these maps for global magnetic perturbations. Magnetometer measurements would be assimilated by the SuperMAG server using a variety of techniques, either by downloading data at regular intervals from remote servers or by real-time streaming connections. The existing SuperMAG analysis software would then process these measurements to provide the final calibrated data set using the SuperMAG coordinate system. The existing plotting software would then be used to produce regularly updated global plots. The talk will focus on current SuperMAG capabilities illustrating the potential for now-casting and eventually forecasting.

California Power-to-Gas and Power-to-Hydrogen Near-Term Business Case Evaluation

Energy Technology Data Exchange (ETDEWEB)

Eichman, Josh [National Renewable Energy Lab. (NREL), Golden, CO (United States); Flores-Espino, Francisco [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-12-01

Flexible operation of electrolysis systems represents an opportunity to reduce the cost of hydrogen for a variety of end-uses while also supporting grid operations and thereby enabling greater renewable penetration. California is an ideal location to realize that value on account of growing renewable capacity and markets for hydrogen as a fuel cell electric vehicle (FCEV) fuel, refineries, and other end-uses. Shifting the production of hydrogen to avoid high cost electricity and participation in utility and system operator markets along with installing renewable generation to avoid utility charges and increase revenue from the Low Carbon Fuel Standard (LCFS) program can result in around $2.5/kg (21%) reduction in the production and delivery cost of hydrogen from electrolysis. This reduction can be achieved without impacting the consumers of hydrogen. Additionally, future strategies for reducing hydrogen cost were explored and include lower cost of capital, participation in the Renewable Fuel Standard program, capital cost reduction, and increased LCFS value. Each must be achieved independently and could each contribute to further reductions. Using the assumptions in this study found a 29% reduction in cost if all future strategies are realized. Flexible hydrogen production can simultaneously improve the performance and decarbonize multiple energy sectors. The lessons learned from this study should be used to understand near-term cost drivers and to support longer-term research activities to further improve cost effectiveness of grid integrated electrolysis systems.

Hydrogen arcjet technology

Science.gov (United States)

Sankovic, John M.; Hamley, John A.; Haag, Thomas W.; Sarmiento, Charles J.; Curran, Francis M.

1991-01-01

During the 1960's, a substantial research effort was centered on the development of arcjets for space propulsion applications. The majority of the work was at the 30 kW power level with some work at 1-2 kW. At the end of the research effort, the hydrogen arcjet had demonstrated over 700 hours of life in a continuous endurance test at 30 kW, at a specific impulse over 1000 s, and at an efficiency of 0.41. Another high power design demonstrated 500 h life with an efficiency of over 0.50 at the same specific impulse and power levels. At lower power levels, a life of 150 hours was demonstrated at 2 kW with an efficiency of 0.31 and a specific impulse of 935 s. Lack of a space power source hindered arcjet acceptance and research ceased. Over three decades after the first research began, renewed interest exists for hydrogen arcjets. The new approach includes concurrent development of the power processing technology with the arcjet thruster. Performance data were recently obtained over a power range of 0.3-30 kW. The 2 kW performance has been repeated; however, the present high power performance is lower than that obtained in the 1960's at 30 kW, and lifetimes of present thrusters have not yet been demonstrated. Laboratory power processing units have been developed and operated with hydrogen arcjets for the 0.1 kW to 5 kW power range. A 10 kW power processing unit is under development and has been operated at design power into a resistive load.

Ultralow power continuous-wave frequency conversion in hydrogenated amorphous silicon waveguides.

Science.gov (United States)

Wang, Ke-Yao; Foster, Amy C

2012-04-15

We demonstrate wavelength conversion through nonlinear parametric processes in hydrogenated amorphous silicon (a-Si:H) with maximum conversion efficiency of -13 dB at telecommunication data rates (10 GHz) using only 15 mW of pump peak power. Conversion bandwidths as large as 150 nm (20 THz) are measured in continuous-wave regime at telecommunication wavelengths. The nonlinear refractive index of the material is determined by four-wave mixing (FWM) to be n(2)=7.43×10(-13) cm(2)/W, approximately an order of magnitude larger than that of single crystal silicon. © 2012 Optical Society of America

Low-CO(2) electricity and hydrogen: a help or hindrance for electric and hydrogen vehicles?

Science.gov (United States)

Wallington, T J; Grahn, M; Anderson, J E; Mueller, S A; Williander, M I; Lindgren, K

2010-04-01

The title question was addressed using an energy model that accounts for projected global energy use in all sectors (transportation, heat, and power) of the global economy. Global CO(2) emissions were constrained to achieve stabilization at 400-550 ppm by 2100 at the lowest total system cost (equivalent to perfect CO(2) cap-and-trade regime). For future scenarios where vehicle technology costs were sufficiently competitive to advantage either hydrogen or electric vehicles, increased availability of low-cost, low-CO(2) electricity/hydrogen delayed (but did not prevent) the use of electric/hydrogen-powered vehicles in the model. This occurs when low-CO(2) electricity/hydrogen provides more cost-effective CO(2) mitigation opportunities in the heat and power energy sectors than in transportation. Connections between the sectors leading to this counterintuitive result need consideration in policy and technology planning.

Forecasting Financial Extremes: A Network Degree Measure of Super-Exponential Growth.

Directory of Open Access Journals (Sweden)

Wanfeng Yan

Full Text Available Investors in stock market are usually greedy during bull markets and scared during bear markets. The greed or fear spreads across investors quickly. This is known as the herding effect, and often leads to a fast movement of stock prices. During such market regimes, stock prices change at a super-exponential rate and are normally followed by a trend reversal that corrects the previous overreaction. In this paper, we construct an indicator to measure the magnitude of the super-exponential growth of stock prices, by measuring the degree of the price network, generated from the price time series. Twelve major international stock indices have been investigated. Error diagram tests show that this new indicator has strong predictive power for financial extremes, both peaks and troughs. By varying the parameters used to construct the error diagram, we show the predictive power is very robust. The new indicator has a better performance than the LPPL pattern recognition indicator.

Forecasting Financial Extremes: A Network Degree Measure of Super-Exponential Growth.

Science.gov (United States)

Yan, Wanfeng; van Tuyll van Serooskerken, Edgar

2015-01-01

Investors in stock market are usually greedy during bull markets and scared during bear markets. The greed or fear spreads across investors quickly. This is known as the herding effect, and often leads to a fast movement of stock prices. During such market regimes, stock prices change at a super-exponential rate and are normally followed by a trend reversal that corrects the previous overreaction. In this paper, we construct an indicator to measure the magnitude of the super-exponential growth of stock prices, by measuring the degree of the price network, generated from the price time series. Twelve major international stock indices have been investigated. Error diagram tests show that this new indicator has strong predictive power for financial extremes, both peaks and troughs. By varying the parameters used to construct the error diagram, we show the predictive power is very robust. The new indicator has a better performance than the LPPL pattern recognition indicator.

Hydrogen storage technology materials and applications

CERN Document Server

Klebanoff, Lennie

2012-01-01

Zero-carbon, hydrogen-based power technology offers the most promising long-term solution for a secure and sustainable energy infrastructure. With contributions from the world's leading technical experts in the field, Hydrogen Storage Technology: Materials and Applications presents a broad yet unified account of the various materials science, physics, and engineering aspects involved in storing hydrogen gas so that it can be used to provide power. The book helps you understand advanced hydrogen storage materials and how to build systems around them. Accessible to nonscientists, the first chapt

Towards an Ultrasonic Guided Wave Procedure for Health Monitoring of Composite Vessels: Application to Hydrogen-Powered Aircraft

Directory of Open Access Journals (Sweden)

Slah Yaacoubi

2017-09-01

Full Text Available This paper presents an overview and description of the approach to be used to investigate the behavior and the defect sensitivity of various ultrasonic guided wave (UGW modes propagating specifically in composite cylindrical vessels in the framework of the safety of hydrogen energy transportation such as hydrogen-powered aircrafts. These structures which consist of thick and multi-layer composites are envisioned for housing hydrogen gas at high pressures. Due to safety concerns associated with a weakened structure, structural health monitoring techniques are needed. A procedure for optimizing damage detection in these structural types is presented. It is shown that a finite element method can help identify useful experimental parameters including frequency range, excitation type, and receiver placement.

Hydrogen storage container

Science.gov (United States)

Wang, Jy-An John; Feng, Zhili; Zhang, Wei

2017-02-07

An apparatus and system is described for storing high-pressure fluids such as hydrogen. An inner tank and pre-stressed concrete pressure vessel share the structural and/or pressure load on the inner tank. The system and apparatus provide a high performance and low cost container while mitigating hydrogen embrittlement of the metal tank. System is useful for distributing hydrogen to a power grid or to a vehicle refueling station.

Global Assessment of Hydrogen Technologies – Task 5 Report Use of Fuel Cell Technology in Electric Power Generation

Energy Technology Data Exchange (ETDEWEB)

Fouad, Fouad H.; Peters, Robert W.; Sisiopiku, Virginia P.; Sullivan Andrew J.; Ahluwalia, Rajesh K.

2007-12-01

The purpose of this work was to assess the performance of high temperature membranes and observe the impact of different parameters, such as water-to-carbon ratio, carbon formation, hydrogen formation, efficiencies, methane formation, fuel and oxidant utilization, sulfur reduction, and the thermal efficiency/electrical efficiency relationship, on fuel cell performance. A 250 KW PEM fuel cell model was simulated [in conjunction with Argonne National Laboratory (ANL) with the help of the fuel cell computer software model (GCtool)] which would be used to produce power of 250 kW and also produce steam at 120oC that can be used for industrial applications. The performance of the system was examined by estimating the various electrical and thermal efficiencies achievable, and by assessing the effect of supply water temperature, process water temperature, and pressure on thermal performance. It was concluded that increasing the fuel utilization increases the electrical efficiency but decreases the thermal efficiency. The electrical and thermal efficiencies are optimum at ~85% fuel utilization. The low temperature membrane (70oC) is unsuitable for generating high-grade heat suitable for useful cogeneration. The high temperature fuel cells are capable of producing steam through 280oC that can be utilized for industrial applications. Increasing the supply water temperature reduces the efficiency of the radiator. Increasing the supply water temperature beyond the dew point temperature decreases the thermal efficiency with the corresponding decrease in high-grade heat utilization. Increasing the steam pressure decreases the thermal efficiency. The environmental impacts of fuel cell use depend upon the source of the hydrogen rich fuel used. By using pure hydrogen, fuel cells have virtually no emissions except water. Hydrogen is rarely used due to problems with storage and transportation, but in the future, the growth of a “solar hydrogen economy” has been projected

Is there room for hydrogen in energy transition?

International Nuclear Information System (INIS)

Beeker, Etienne

2014-08-01

As Germany decided to use hydrogen to store huge quantities of renewable energies, this report aims at assessing the opportunities associated with hydrogen in the context of energy transition. The author addresses the various techniques and technologies of hydrogen production, and proposes a prospective economic analysis of these processes: steam reforming, alkaline electrolysis, polymer electrolyte membrane (PEM) electrolysis, and other processes still at R and D level. He gives an overview of existing and potential uses of hydrogen in industry, in energy storage (power-to-gas, power-to-power, methanation) and in mobility (hydrogen-mobility could be a response to hydrocarbon shortage, but the cost is still very high, and issues like hydrogen distribution must be addressed), and also evokes their emergence potential

Propagation dynamics of super-Gaussian beams in fractional Schrödinger equation: from linear to nonlinear regimes.

Science.gov (United States)

Zhang, Lifu; Li, Chuxin; Zhong, Haizhe; Xu, Changwen; Lei, Dajun; Li, Ying; Fan, Dianyuan

2016-06-27

We have investigated the propagation dynamics of super-Gaussian optical beams in fractional Schrödinger equation. We have identified the difference between the propagation dynamics of super-Gaussian beams and that of Gaussian beams. We show that, the linear propagation dynamics of the super-Gaussian beams with order m > 1 undergo an initial compression phase before they split into two sub-beams. The sub-beams with saddle shape separate each other and their interval increases linearly with propagation distance. In the nonlinear regime, the super-Gaussian beams evolve to become a single soliton, breathing soliton or soliton pair depending on the order of super-Gaussian beams, nonlinearity, as well as the Lévy index. In two dimensions, the linear evolution of super-Gaussian beams is similar to that for one dimension case, but the initial compression of the input super-Gaussian beams and the diffraction of the splitting beams are much stronger than that for one dimension case. While the nonlinear propagation of the super-Gaussian beams becomes much more unstable compared with that for the case of one dimension. Our results show the nonlinear effects can be tuned by varying the Lévy index in the fractional Schrödinger equation for a fixed input power.

Fuel processor for fuel cell power system. [Conversion of methanol into hydrogen

Science.gov (United States)

Vanderborgh, N.E.; Springer, T.E.; Huff, J.R.

1986-01-28

A catalytic organic fuel processing apparatus, which can be used in a fuel cell power system, contains within a housing a catalyst chamber, a variable speed fan, and a combustion chamber. Vaporized organic fuel is circulated by the fan past the combustion chamber with which it is in indirect heat exchange relationship. The heated vaporized organic fuel enters a catalyst bed where it is converted into a desired product such as hydrogen needed to power the fuel cell. During periods of high demand, air is injected upstream of the combustion chamber and organic fuel injection means to burn with some of the organic fuel on the outside of the combustion chamber, and thus be in direct heat exchange relation with the organic fuel going into the catalyst bed.

Sustainable hydrogen production

Energy Technology Data Exchange (ETDEWEB)

Block, D.L.; Linkous, C.; Muradov, N.

1996-01-01

This report describes the Sustainable Hydrogen Production research conducted at the Florida Solar Energy Center (FSEC) for the past year. The report presents the work done on the following four tasks: Task 1--production of hydrogen by photovoltaic-powered electrolysis; Task 2--solar photocatalytic hydrogen production from water using a dual-bed photosystem; Task 3--development of solid electrolytes for water electrolysis at intermediate temperatures; and Task 4--production of hydrogen by thermocatalytic cracking of natural gas. For each task, this report presents a summary, introduction/description of project, and results.

Super families

International Nuclear Information System (INIS)

Amato, N.; Maldonado, R.H.C.

1989-01-01

The study on phenomena in the super high energy region, Σ E j > 1000 TeV revealed events that present a big dark spot in central region with high concentration of energy and particles, called halo. Six super families with halo were analysed by Brazil-Japan Cooperation of Cosmic Rays. For each family the lateral distribution of energy density was constructed and R c Σ E (R c ) was estimated. For studying primary composition, the energy correlation with particles released separately in hadrons and gamma rays was analysed. (M.C.K.)

H2POWER: Development of a methodology to calculate life cycle cost of small and medium-scale hydrogen systems

International Nuclear Information System (INIS)

Verduzco, Laura E.; Duffey, Michael R.; Deason, Jonathan P.

2007-01-01

At this time, hydrogen-based power plants and large hydrogen production facilities are capital intensive and unable to compete financially against hydrocarbon-based energy production facilities. An option to overcome this problem and foster the introduction of hydrogen technology is to introduce small and medium-scale applications such as residential and community hydrogen refueling units. Such units could potentially be used to generate both electricity and heat for the home, as well as hydrogen fuel for the automobile. Cost modeling for the integration of these three forms of energy presents several methodological challenges. This is particularly true since the technology is still in the development phase and both the financial and the environmental cost must be calculated using mainly secondary sources. In order to address these issues and aid in the design of small and medium-scale hydrogen systems, this study presents a computer model to calculate financial and environmental costs of this technology using different hydrogen pathways. The model can design and compare hydrogen refueling units against hydrocarbon-based technologies, including the 'gap' between financial and economic costs. Using the methodology, various penalties and incentives that can foster the introduction of hydrogen-based technologies can be added to the analysis to study their impact on financial cost

Hydrogen exchange

DEFF Research Database (Denmark)

Jensen, Pernille Foged; Rand, Kasper Dyrberg

2016-01-01

Hydrogen exchange (HX) monitored by mass spectrometry (MS) is a powerful analytical method for investigation of protein conformation and dynamics. HX-MS monitors isotopic exchange of hydrogen in protein backbone amides and thus serves as a sensitive method for probing protein conformation...... and dynamics along the entire protein backbone. This chapter describes the exchange of backbone amide hydrogen which is highly quenchable as it is strongly dependent on the pH and temperature. The HX rates of backbone amide hydrogen are sensitive and very useful probes of protein conformation......, as they are distributed along the polypeptide backbone and form the fundamental hydrogen-bonding networks of basic secondary structure. The effect of pressure on HX in unstructured polypeptides (poly-dl-lysine and oxidatively unfolded ribonuclease A) and native folded proteins (lysozyme and ribonuclease A) was evaluated...

Modelling of hydrogen sulfide dispersion from the geothermal power plants of Tuscany (Italy)

Science.gov (United States)

Renato, Somma; Domenico, Granieri; Claudia, Troise; Carlo, Terranova; Natale Giuseppe, De; Maria, Pedone

2017-04-01

The hydrogen sulfide (H2S) is one of the main gaseous substances contained in deep fluids exploited by geo-thermoelectric plant. Therefore, it is a "waste" pollutant product by plants for energy production. Hydrogen sulfide is perceived by humans at very low concentrations in the air ( 0,008 ppm, World Health Organization, hereafter WHO, 2003) but it becomes odorless in higher concentrations (> 100 ppm, WHO, 2003) and, for values close to the ones lethal (> 500 ppm), produces an almost pleasant smell. The typical concentration in urban areas is <0.001ppm (<1ppb); in volcanic plumes it reaches values between 0.1 and 0.5 ppm. WHO defines the concentration and relative effects on human health. We applied the Eulerian code DISGAS (DISpersion of GAS) to investigate the dispersion of the hydrogen sulfide (H2S) from 32 geothermal power plants (out of 35 active) belonging to the geothermal districts of Larderello, Travale-Radicondoli and Monte Amiata, in Tuscany (Italy). DISGAS code has simulated scenarios consistent with the prevailing wind conditions, estimating reasonable H2S concentrations for each area, and for each active power plant. The results suggest that H2S plumes emitted from geothermal power plants are mainly concentrated around the stacks of emission (H2S concentration up to 1100 ug/m3) and rapidly dilute along the dominant local wind direction. Although estimated values of air H2S concentrations are orders of magnitude higher than in unpolluted areas, they do not indicate an immediate health risk for nearby communities, under the more frequent local atmospheric conditions. Starting from the estimated values, validated by measurements in the field, we make some considerations about the environmental impact of the H2S emission in all the geothermal areas of the Tuscany region. Furthermore, this study indicates the potential of DISGAS as a tool for an improved understanding of the atmospheric and environmental impacts of the H2S continuous degassing from

A new type of hydrogen generator-HHEG (high-compressed hydrogen energy generator)

International Nuclear Information System (INIS)

Harada, H.; Tojima, K.; Takeda, M.; Nakazawa, T.

2004-01-01

'Full text:' We have developed a new type of hydrogen generator named HHEG (High-compressed Hydrogen Energy Generator). HHEG can produce 35 MPa high-compressed hydrogen for fuel cell vehicle without any mechanical compressor. HHEG is a kind of PEM(proton exchange membrane)electrolysis. It was well known that compressed hydrogen could be generated by water electrolysis. However, the conventional electrolysis could not generate 35 MPa or higher pressure that is required for fuel cell vehicle, because electrolysis cell stack is destroyed in such high pressure. In HHEG, the cell stack is put in high-pressure vessel and the pressure difference of oxygen and hydrogen that is generated by the cell stack is always kept at nearly zero by an automatic compensator invented by Mitsubishi Corporation. The cell stack of HHEG is not so special one, but it is not broken under such high pressure, because the automatic compensator always offsets the force acting on the cell stack. Hydrogen for fuel cell vehicle must be produce by no emission energy such as solar and atomic power. These energies are available as electricity. So, water electrolysis is the only way of producing hydrogen fuel. Hydrogen fuel is also 35 MPa high-compressed hydrogen and will become 70 MPa in near future. But conventional mechanical compressor is not useful for such high pressure hydrogen fuel, because of the short lifetime and high power consumption. Construction of hydrogen station network is indispensable in order to come into wide use of fuel cell vehicles. For such network contraction, an on-site type hydrogen generator is required. HHEG can satisfy above these requirements. So we can conclude that HHEG is the only way of realizing the hydrogen economy. (author)

Catalytic Reforming of Higher Hydrocarbon Fuels to Hydrogen: Process Investigations with Regard to Auxiliary Power Units

OpenAIRE

Kaltschmitt, Torsten

2012-01-01

This thesis discusses the investigation of the catalytic partial oxidation on rhodium-coated honeycomb catalysts with respect to the conversion of a model surrogate fuel and commercial diesel fuel into hydrogen for the use in auxiliary power units. Furthermore, the influence of simulated tail-gas recycling was investigated.

High-Sensitivity and Low-Power Flexible Schottky Hydrogen Sensor Based on Silicon Nanomembrane.

Science.gov (United States)

Cho, Minkyu; Yun, Jeonghoon; Kwon, Donguk; Kim, Kyuyoung; Park, Inkyu

2018-04-18

High-performance and low-power flexible Schottky diode-based hydrogen sensor was developed. The sensor was fabricated by releasing Si nanomembrane (SiNM) and transferring onto a plastic substrate. After the transfer, palladium (Pd) and aluminum (Al) were selectively deposited as a sensing material and an electrode, respectively. The top-down fabrication process of flexible Pd/SiNM diode H 2 sensor is facile compared to other existing bottom-up fabricated flexible gas sensors while showing excellent H 2 sensitivity (Δ I/ I 0 > 700-0.5% H 2 concentrations) and fast response time (τ 10-90 = 22 s) at room temperature. In addition, selectivity, humidity, and mechanical tests verify that the sensor has excellent reliability and robustness under various environments. The operating power consumption of the sensor is only in the nanowatt range, which indicates its potential applications in low-power portable and wearable electronics.

Water leak detection in sodium heated steam generators through measurement of hydrogen concentration in sodium

International Nuclear Information System (INIS)

Cambillard, E.; Lacroix, A.; Martin, P.; Viala, J.

1980-07-01

This report includes a description of apparatus for measuring hydrogen concentration in the secondary sodium system of the PHENIX reactor. The calibration method and results obtained since the commissioning of the reactor are also described. Mention is made of improvements to be built into SUPER PHENIX [fr

SuperAGILE Services at ASDC

International Nuclear Information System (INIS)

Preger, B.; Verrecchia, F.; Pittori, C.; Antonelli, L. A.; Giommi, P.; Lazzarotto, F.; Evangelista, Y.

2008-01-01

The Italian Space Agency Science Data Center (ASDC) is a facility with several responsibilities including support to all the ASI scientific missions as for management and archival of the data, acting as the interface between ASI and the scientific community and providing on-line access to the data hosted. In this poster we describe the services that ASDC provides for SuperAGILE, in particular the ASDC public web pages devoted to the dissemination of SuperAGILE scientific results. SuperAGILE is the X-Ray imager onboard the AGILE mission, and provides the scientific community with orbit-by-orbit information on the observed sources. Crucial source information including position and flux in chosen energy bands will be reported in the SuperAGILE public web page at ASDC. Given their particular interest, another web page will be dedicated entirely to GRBs and other transients, where new event alerts will be notified and where users will find all the available informations on the GRBs detected by SuperAGILE

Primary energy sources for hydrogen production

International Nuclear Information System (INIS)

Hassmann, K.; Kuehne, H.-M.

1993-01-01

The cost of hydrogen from water electrolysis is estimated, assuming that the electricity was produced from solar, hydro-, fossil, or nuclear power. The costs for hydrogen end-use in the sectors of power generation, heat and transportation are calculated, based on a state-of-the-art technology and a more advanced technology expected to represent the state by the year 2010. The cost of hydrogen utilization (without energy taxes) is higher than the current price of fossil fuels (including taxes). Without restrictions imposed on fossil fuel consumption, hydrogen will not gain a significant market share in either of the cases discussed. (Author)

The Super-Kamiokande detector

International Nuclear Information System (INIS)

Fukuda, S.; Fukuda, Y.; Hayakawa, T.; Ichihara, E.; Ishitsuka, M.; Itow, Y.; Kajita, T.; Kameda, J.; Kaneyuki, K.; Kasuga, S.; Kobayashi, K.; Kobayashi, Y.; Koshio, Y.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakayama, S.; Namba, T.; Obayashi, Y.; Okada, A.; Oketa, M.; Okumura, K.; Oyabu, T.; Sakurai, N.; Shiozawa, M.; Suzuki, Y.; Takeuchi, Y.; Toshito, T.; Totsuka, Y.; Yamada, S.; Desai, S.; Earl, M.; Hong, J.T.; Kearns, E.; Masuzawa, M.; Messier, M.D.; Stone, J.L.; Sulak, L.R.; Walter, C.W.; Wang, W.; Scholberg, K.; Barszczak, T.; Casper, D.; Liu, D.W.; Gajewski, W.; Halverson, P.G.; Hsu, J.; Kropp, W.R.; Mine, S.; Price, L.R.; Reines, F.; Smy, M.; Sobel, H.W.; Vagins, M.R.; Ganezer, K.S.; Keig, W.E.; Ellsworth, R.W.; Tasaka, S.; Flanagan, J.W.; Kibayashi, A.; Learned, J.G.; Matsuno, S.; Stenger, V.J.; Hayato, Y.; Ishii, T.; Ichikawa, A.; Kanzaki, J.; Kobayashi, T.; Maruyama, T.; Nakamura, K.; Oyama, Y.; Sakai, A.; Sakuda, M.; Sasaki, O.; Echigo, S.; Iwashita, T.; Kohama, M.; Suzuki, A.T.; Hasegawa, M.; Inagaki, T.; Kato, I.; Maesaka, H.; Nakaya, T.; Nishikawa, K.; Yamamoto, S.; Haines, T.J.; Kim, B.K.; Sanford, R.; Svoboda, R.; Blaufuss, E.; Chen, M.L.; Conner, Z.; Goodman, J.A.; Guillian, E.; Sullivan, G.W.; Turcan, D.; Habig, A.; Ackerman, M.; Goebel, F.; Hill, J.; Jung, C.K.; Kato, T.; Kerr, D.; Malek, M.; Martens, K.; Mauger, C.; McGrew, C.; Sharkey, E.; Viren, B.; Yanagisawa, C.; Doki, W.; Inaba, S.; Ito, K.; Kirisawa, M.; Kitaguchi, M.; Mitsuda, C.; Miyano, K.; Saji, C.; Takahata, M.; Takahashi, M.; Higuchi, K.; Kajiyama, Y.; Kusano, A.; Nagashima, Y.; Nitta, K.; Takita, M.; Yamaguchi, T.; Yoshida, M.; Kim, H.I.; Kim, S.B.; Yoo, J.; Okazawa, H.; Etoh, M.; Fujita, K.; Gando, Y.; Hasegawa, A.; Hasegawa, T.; Hatakeyama, S.; Inoue, K.; Ishihara, K.; Iwamoto, T.; Koga, M.; Nishiyama, I.; Ogawa, H.; Shirai, J.; Suzuki, A.; Takayama, T.; Tsushima, F.; Koshiba, M.; Ichikawa, Y.; Hashimoto, T.; Hatakeyama, Y.; Koike, M.; Horiuchi, T.; Nemoto, M.; Nishijima, K.; Takeda, H.; Fujiyasu, H.; Futagami, T.; Ishino, H.; Kanaya, Y.; Morii, M.; Nishihama, H.; Nishimura, H.; Suzuki, T.; Watanabe, Y.; Kielczewska, D.; Golebiewska, U.; Berns, H.G.; Boyd, S.B.; Doyle, R.A.; George, J.S.; Stachyra, A.L.; Wai, L.L.; Wilkes, R.J.; Young, K.K.; Kobayashi, H.

2003-01-01

Super-Kamiokande is the world's largest water Cherenkov detector, with net mass 50,000 tons. During the period April, 1996 to July, 2001, Super-Kamiokande I collected 1678 live-days of data, observing neutrinos from the Sun, Earth's atmosphere, and the K2K long-baseline neutrino beam with high efficiency. These data provided crucial information for our current understanding of neutrino oscillations, as well as setting stringent limits on nucleon decay. In this paper, we describe the detector in detail, including its site, configuration, data acquisition equipment, online and offline software, and calibration systems which were used during Super-Kamiokande I

Integrated waste hydrogen utilization project

International Nuclear Information System (INIS)

Armstrong, C.

2004-01-01

'Full text:' The BC Hydrogen Highway's, Integrated Waste Hydrogen Utilization Project (IWHUP) is a multi-faceted, synergistic collaboration that will capture waste hydrogen and promote its use through the demonstration of 'Hydrogen Economy' enabling technologies developed by Canadian companies. IWHUP involves capturing and purifying a small portion of the 600 kg/hr of by-product hydrogen vented to the atmosphere at the ERCO's electrochemical sodium chlorate plant in North Vancouver, BC. The captured hydrogen will then be compressed so it is suitable for transportation on roadways and can be used as a fuel in transportation and stationary fuel cell demonstrations. In summary, IWHUP invests in the following; Facilities to produce up to 20kg/hr of 99.999% pure 6250psig hydrogen using QuestAir's leading edge Pressure Swing Absorption technology; Ultra high-pressure transportable hydrogen storage systems developed by Dynetek Industries, Powertech Labs and Sacre-Davey Engineering; A Mobile Hydrogen Fuelling Station to create Instant Hydrogen Infrastructure for light-duty vehicles; Natural gas and hydrogen (H-CNG) blending and compression facilities by Clean Energy for fueling heavy-duty vehicles; Ten hydrogen, internal combustion engine (H-ICE), powered light duty pick-up vehicles and a specialized vehicle training, maintenance, and emissions monitoring program with BC Hydro, GVRD and the District of North Vancouver; The demonstration of Westport's H-CNG technology for heavy-duty vehicles in conjunction with local transit properties and a specialized vehicle training, maintenance, and emissions monitoring program; The demonstration of stationary fuel cell systems that will provide clean power for reducing peak-load power demands (peak shaving), grid independence and water heating; A comprehensive communications and outreach program designed to educate stakeholders, the public, regulatory bodies and emergency response teams in the local community, Supported by industry

Potential Environmental Impacts of Hydrogen-based Transportation and Power Systems

Energy Technology Data Exchange (ETDEWEB)

Grieb, Thomas M; Mills, W B; Jacobson, Mark Z; Summers, Karen V; Crossan, A Brook

2010-12-31

Hydrogen (H2) offers advantages as an energy carrier: minimal discharge of pollutants, production from multiple sources, increased thermodynamic efficiencies compared to fossil fuels, and reduced dependence on foreign oil. However, potential impacts from the H2 generation processes, transport and distribution of H2, and releases of H2 into the atmosphere have been proposed. The goal of this project was to analyze the effects of emissions of hydrogen, the six criteria pollutants and greenhouse gases on climate, human health, materials and structures. This project was part of a larger effort by DOE to assess the life-cycle costs and benefits and environmental impacts to inform decisions regarding future hydrogen research. Technical Approach: A modeling approach was developed and used to evaluate the potential environmental effects associated with the conversion of the on-road vehicle fleet from fossil-fuel vehicles to hydrogen fuel cell vehicles. GATOR-GCMOM was the primary tool used to predict atmospheric concentrations of gases and aerosols for selected scenarios. This model accounts for all feedbacks among major atmospheric processes based on first principles. The future scenarios and the emission rates selected for this analysis of hydrogen environmental effects are based on the scenarios developed by IPCC. The scenarios selected for the model simulations are a 2000 and 2050 A1B base cases, and a 2050 A1B case with hydrogen fuel cell vehicles (HFCVs). The hydrogen fuel cell scenario assumed conversion of 90% of fossil-fuel on-road vehicles (FFOV) in developed countries and 45% of FFOVs vehicles in other countries to HFCVs, with the H2 produced by steam-reforming of natural gas (SHFCVs). Simulations were conducted to examine the effect of converting the world's FFOVs to HFCVs, where the H2 is produced by wind-powered electrolysis (WHFCVs). In all scenarios a 3% leakage of H2 consumed was assumed. Two new models were developed that provide the ability to

Generation of live offspring from vitrified embryos with synthetic polymers SuperCool X-1000 and SuperCool Z-1000.

Science.gov (United States)

Marco-Jimenez, F; Jimenez-Trigos, E; Lavara, R; Vicente, J S

2014-01-01

Ice growth and recrystallisation are considered important factors in determining vitrification outcomes. Synthetic polymers inhibit ice formation during cooling or warming of the vitrification process. The aim of this study was to assess the effect of adding commercially available synthetic polymers SuperCool X-1000 and SuperCool Z-1000 to vitrification media on in vivo development competence of rabbit embryos. Four hundred and thirty morphologically normal embryos recovered at 72 h of gestation were used. The vitrification media contained 20% dimethyl sulphoxide and 20% ethylene glycol, either alone or in combination with 1% of SuperCool X-1000 and 1% SuperCool. Our results show that embryos can be successfully vitrified using SuperCool X-1000 and SuperCool Z-1000 and when embryos are transferred, live offspring can be successfully produced. In conclusion, our results demonstrated that we succeeded for the first time in obtaining live offspring after vitrification of embryos using SuperCool X-1000 and SuperCool Z-1000 polymers.

High speed data transmission at the Superconducting Super Collider

International Nuclear Information System (INIS)

Leskovar, B.

1990-04-01

High speed data transmission using fiber optics in the data acquisition system of the Superconducting Super Collider has been investigated. Emphasis is placed on the high speed data transmission system overview, the local data network and on subassemblies, such as optical transmitters and receivers. Also, the performance of candidate subassemblies having a low power dissipation for the data acquisition system is discussed. 14 refs., 5 figs

Further results on super graceful labeling of graphs

Directory of Open Access Journals (Sweden)

Gee-Choon Lau

2016-08-01

Full Text Available Let G=(V(G,E(G be a simple, finite and undirected graph of order p and size q. A bijection f:V(G∪E(G→{k,k+1,k+2,…,k+p+q−1} such that f(uv=|f(u−f(v| for every edge uv∈E(G is said to be a k-super graceful labeling of G. We say G is k-super graceful if it admits a k-super graceful labeling. For k=1, the function f is called a super graceful labeling and a graph is super graceful if it admits a super graceful labeling. In this paper, we study the super gracefulness of complete graph, the disjoint union of certain star graphs, the complete tripartite graphs K(1,1,n, and certain families of trees. We also present four methods of constructing new super graceful graphs. In particular, all trees of order at most 7 are super graceful. We conjecture that all trees are super graceful.

Super oil cracking update

International Nuclear Information System (INIS)

Mulraney, D.

1997-01-01

The conversion of residual fuel oil to usable middle distillates was discussed. The residue conversion processing paths are usually based on separation, carbon rejection, or hydrogen addition principles. Super Oil Cracking (SOC) uses a slurry catalyst system in a new, tubular reactor to achieve high levels of hydrothermal conversion. SOC can upgrade a variety of heavy, high metals residue feedstocks with high yields of middle distillates. The SOC products can also be further treated into feedstocks for FCC or hydrocracking. The SOC process can be incorporated easily into a refinery to obtain incremental residue conversion directly. It can also be integrated with other residue processes, acting as a demetallization and decarbonization step which results in enhanced overall conversion. The relative rate of coke formation and its handling are distinguishing characteristics between residue upgrading technologies. The SOC process operates at higher temperatures that other residue hydrocracking processes resulting in higher rates of thermal decomposition, thus preventing coke formation. SOC process can operate as a stand-alone upgrader or can be integrated with other bottoms processing steps to extend the refiner's range of options for increasing bottoms conversion.3 tabs., 14 figs

Development of Premacy Hydrogen RE Hybrid

Energy Technology Data Exchange (ETDEWEB)

Wakayama, N. [Mazda Motor Corporation, Hiroshima (Japan)

2010-07-01

Hydrogen powered ICE (internal combustion engine) vehicles can play an important role as an automotive power source in the future, because of its higher reliability and cost performance than those of fuel cell vehicles. Combined with hydrogen, Mazda's unique rotary engine (RE) has merits such as a prevention of hydrogen pre-ignition. Mazda has been developing hydrogen vehicles with the hydrogen RE from the early 1990s. Premacy (Mazda5) Hydrogen RE Hybrid was developed and launched in 2009, following RX-8 Hydrogen RE delivered in 2006. A series hybrid system was adopted in Premacy Hydrogen RE Hybrid. A traction motor switches its windings while the vehicle is moving. This switching technology allows the motor to be small and high-efficient. The lithium-ion high voltage battery, which has excellent input-output characteristics, was installed. These features extend the hydrogen fuel driving range to 200 km and obtain excellent acceleration performance. The hydrogen RE can be also operated by gasoline (Dual Fuel System). The additional gasoline operation makes hydrogen vehicles possible to drive in non-hydrogen station area. With approval from the Japanese Ministry of Land Infrastructure and Transport, Mazda Premacy Hydrogen RE Hybrid was delivered successfully to the Japanese market in the form of leasing. (orig.)

The hydrogen mine introduction initiative

Energy Technology Data Exchange (ETDEWEB)

Betournay, M.C.; Howell, B. [Natural Resources Canada, Ottawa, ON (Canada). CANMET Mining and Mineral Sciences Laboratories

2009-07-01

In an effort to address air quality concerns in underground mines, the mining industry is considering the use fuel cells instead of diesel to power mine production vehicles. The immediate issues and opportunities associated with fuel cells use include a reduction in harmful greenhouse gas emissions; reduction in ventilation operating costs; reduction in energy consumption; improved health benefits; automation; and high productivity. The objective of the hydrogen mine introduction initiative (HMII) is to develop and test the range of fundamental and needed operational technology, specifications and best practices for underground hydrogen power applications. Although proof of concept studies have shown high potential for fuel cell use, safety considerations must be addressed, including hydrogen behaviour in confined conditions. This presentation highlighted the issues to meet operational requirements, notably hydrogen production; delivery and storage; mine regulations; and hydrogen behaviour underground. tabs., figs.

Comprehensive Understanding of Ductility Loss Mechanisms in Various Steels with External and Internal Hydrogen

Science.gov (United States)

Takakuwa, Osamu; Yamabe, Junichiro; Matsunaga, Hisao; Furuya, Yoshiyuki; Matsuoka, Saburo

2017-11-01

Hydrogen-induced ductility loss and related fracture morphologies are comprehensively discussed in consideration of the hydrogen distribution in a specimen with external and internal hydrogen by using 300-series austenitic stainless steels (Types 304, 316, 316L), high-strength austenitic stainless steels (HP160, XM-19), precipitation-hardened iron-based super alloy (A286), low-alloy Cr-Mo steel (JIS-SCM435), and low-carbon steel (JIS-SM490B). External hydrogen is realized by a non-charged specimen tested in high-pressure gaseous hydrogen, and internal hydrogen is realized by a hydrogen-charged specimen tested in air or inert gas. Fracture morphologies obtained by slow-strain-rate tensile tests (SSRT) of the materials with external or internal hydrogen could be comprehensively categorized into five types: hydrogen-induced successive crack growth, ordinary void formation, small-sized void formation related to the void sheet, large-sized void formation, and facet formation. The mechanisms of hydrogen embrittlement are broadly classified into hydrogen-enhanced decohesion (HEDE) and hydrogen-enhanced localized plasticity (HELP). In the HEDE model, hydrogen weakens interatomic bonds, whereas in the HELP model, hydrogen enhances localized slip deformations. Although various fracture morphologies are produced by external or internal hydrogen, these morphologies can be explained by the HELP model rather than by the HEDE model.

Multi-objective stochastic distribution feeder reconfiguration problem considering hydrogen and thermal energy production by fuel cell power plants

International Nuclear Information System (INIS)

Niknam, Taher; Kavousi Fard, Abdollah; Baziar, Aliasghar

2012-01-01

This paper assesses the operation and management of electrical energy, hydrogen production and thermal load supplement by the Fuel Cell Power Plants (FCPP) in the distribution systems with regard to the uncertainties which exist in the load demand as well as the price of buying natural gas for FCPPs, fuel cost for residential loads, tariff for purchasing electricity, tariff for selling electricity, hydrogen selling price, operation and maintenance cost and the price of purchasing power from the grid. Therefore, a new modified multi-objective optimization algorithm called Teacher-Learning Algorithm (TLA) is proposed to integrate the optimal operation management of Proton Exchange Membrane FCPPs (PEM-FCPPs) and the optimal configuration of the system through an economic model of the PEM-FCPP. In order to improve the total ability of TLA for global search and exploration, a new modification process is suggested such that the algorithm will search the total search space globally. Also, regarding the uncertainties of the new complicated power systems, in this paper for the first time, the DFR problem is investigated in a stochastic environment by the use of probabilistic load flow technique based on Point Estimate Method (PEM). In order to see the feasibility and the superiority of the proposed method, a standard test system is investigated as the case study. The simulation results are investigated in four different scenarios to show the effect of hydrogen production and thermal recovery more evidently. -- Highlights: ► Present an economical and thermal modeling of PEM-FCPPs. ► Present an approach for optimal operation of PEM-FCPPs in a stochastic environment. ► Consider benefits of thermal recovery and Hydrogen production for PEM-FCPPs. ► Present several scenarios for management of PEM-FCPPs.

Super cool X-1000 and Super cool Z-1000, two ice blockers, and their effect on vitrification/warming of mouse embryos.

Science.gov (United States)

Badrzadeh, H; Najmabadi, S; Paymani, R; Macaso, T; Azadbadi, Z; Ahmady, A

2010-07-01

To evaluate the survival and blastocyst formation rates of mouse embryos after vitrification/thaw process with different ice blocker media. We used X-1000 and Z-1000 separately and mixed using V-Kim, a closed vitrification system. Mouse embryos were vitrified using ethylene glycol based medium supplemented with Super cool X-1000 and/or Super cool Z-1000. Survival rates for the control, Super cool X-1000, Super cool Z-1000, and Super cool X-1000/Z-1000 groups were 74%, 72%, 68%, and 85% respectively, with no significant difference among experimental and control groups; however, a significantly higher survival rate was noticed in the Super cool X-1000/Z-1000 group when compared with the Super cool Z-1000 group. Blastocyst formation rates for the control, Super cool X-1000, Super cool Z-1000, and Super cool X-1000/Z-1000 groups were 71%, 66%, 65%, and 72% respectively. There was no significant difference in this rate among control and experimental groups. In a closed vitrification system, addition of ice blocker Super cool X-1000 to the vitrification solution containing Super cool Z-1000 may improve the embryo survival rate. We recommend combined ice blocker usage to optimize the vitrification outcome. Copyright (c) 2010 Elsevier Ireland Ltd. All rights reserved.

Superstring field theories on super-flag manifolds: superdiff S1/S1 and superdiff S1/super S1

International Nuclear Information System (INIS)

Zhao Zhiyong; Wu, Ke; Saito, Takesi

1987-01-01

We generalize the geometric approach of Bowick and Rajeev [BR] to superstring field theories. The anomaly is identified with nonvanishing of the Ricci curvature of the super-flag manifold. We explicitly calculate the curvatures of superdiff S 1 /S 1 and superdiff S 1 /superS 1 using super-Toeplitz operator techniques. No regularization is needed in this formalism. The critical dimension D=10 is rediscovered as a result of vanishing curvature of the product bundle over the super-flag manifold. (orig.)

A mathematical model of the maximum power density attainable in an alkaline hydrogen/oxygen fuel cell

Science.gov (United States)

Kimble, Michael C.; White, Ralph E.

1991-01-01

A mathematical model of a hydrogen/oxygen alkaline fuel cell is presented that can be used to predict the polarization behavior under various power loads. The major limitations to achieving high power densities are indicated and methods to increase the maximum attainable power density are suggested. The alkaline fuel cell model describes the phenomena occurring in the solid, liquid, and gaseous phases of the anode, separator, and cathode regions based on porous electrode theory applied to three phases. Fundamental equations of chemical engineering that describe conservation of mass and charge, species transport, and kinetic phenomena are used to develop the model by treating all phases as a homogeneous continuum.

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

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

2006-07-01

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

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

T Tafticht; K Agbossou

2006-01-01

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

Hydrogen Production from Optimal Wind-PV Energies Systems

International Nuclear Information System (INIS)

Tafticht, T.; Agbossou, K.

2006-01-01

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

Hydrogen Production from Optimal Wind-PV Energies Systems

Energy Technology Data Exchange (ETDEWEB)

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

2006-07-01

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

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

International Nuclear Information System (INIS)

2006-01-01

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

SuperB Progress Report for Physics

Energy Technology Data Exchange (ETDEWEB)

O' Leary, B.; /Aachen, Tech. Hochsch.; Matias, J.; Ramon, M.; /Barcelona, IFAE; Pous, E.; /Barcelona U.; De Fazio, F.; Palano, A.; /INFN, Bari; Eigen, G.; /Bergen U.; Asgeirsson, D.; /British Columbia U.; Cheng, C.H.; Chivukula, A.; Echenard, B.; Hitlin, D.G.; Porter, F.; Rakitin, A.; /Caltech; Heinemeyer, S.; /Cantabria Inst. of Phys.; McElrath, B.; /CERN; Andreassen, R.; Meadows, B.; Sokoloff, M.; /Cincinnati U.; Blanke, M.; /Cornell U., Phys. Dept.; Lesiak, T.; /Cracow, INP /DESY /Zurich, ETH /INFN, Ferrara /Frascati /INFN, Genoa /Glasgow U. /Indiana U. /Mainz U., Inst. Phys. /Karlsruhe, Inst. Technol. /KEK, Tsukuba /LBL, Berkeley /UC, Berkeley /Lisbon, IST /Ljubljana U. /Madrid, Autonoma U. /Maryland U. /MIT /INFN, Milan /McGill U. /Munich, Tech. U. /Notre Dame U. /PNL, Richland /INFN, Padua /Paris U., VI-VII /Orsay, LAL /Orsay, LPT /INFN, Pavia /INFN, Perugia /INFN, Pisa /Queen Mary, U. of London /Regensburg U. /Republica U., Montevideo /Frascati /INFN, Rome /INFN, Rome /INFN, Rome /Rutherford /Sassari U. /Siegen U. /SLAC /Southern Methodist U. /Tel Aviv U. /Tohoku U. /INFN, Turin /INFN, Trieste /Uppsala U. /Valencia U., IFIC /Victoria U. /Wayne State U. /Wisconsin U., Madison

2012-02-14

SuperB is a high luminosity e{sup +}e{sup -} collider that will be able to indirectly probe new physics at energy scales far beyond the reach of any man made accelerator planned or in existence. Just as detailed understanding of the Standard Model of particle physics was developed from stringent constraints imposed by flavour changing processes between quarks, the detailed structure of any new physics is severely constrained by flavour processes. In order to elucidate this structure it is necessary to perform a number of complementary studies of a set of golden channels. With these measurements in hand, the pattern of deviations from the Standard Model behavior can be used as a test of the structure of new physics. If new physics is found at the LHC, then the many golden measurements from SuperB will help decode the subtle nature of the new physics. However if no new particles are found at the LHC, SuperB will be able to search for new physics at energy scales up to 10-100 TeV. In either scenario, flavour physics measurements that can be made at SuperB play a pivotal role in understanding the nature of physics beyond the Standard Model. Examples for using the interplay between measurements to discriminate New Physics models are discussed in this document. SuperB is a Super Flavour Factory, in addition to studying large samples of B{sub u,d,s}, D and {tau} decays, SuperB has a broad physics programme that includes spectroscopy both in terms of the Standard Model and exotica, and precision measurements of sin{sup 2} {theta}{sub W}. In addition to performing CP violation measurements at the {Upsilon}(4S) and {phi}(3770), SuperB will test CPT in these systems, and lepton universality in a number of different processes. The multitude of rare decay measurements possible at SuperB can be used to constrain scenarios of physics beyond the Standard Model. In terms of other precision tests of the Standard Model, this experiment will be able to perform precision over

SuperB Progress Report for Physics

International Nuclear Information System (INIS)

O'Leary, B.; Matias, J.; Ramon, M.

2012-01-01

SuperB is a high luminosity e + e - collider that will be able to indirectly probe new physics at energy scales far beyond the reach of any man made accelerator planned or in existence. Just as detailed understanding of the Standard Model of particle physics was developed from stringent constraints imposed by flavour changing processes between quarks, the detailed structure of any new physics is severely constrained by flavour processes. In order to elucidate this structure it is necessary to perform a number of complementary studies of a set of golden channels. With these measurements in hand, the pattern of deviations from the Standard Model behavior can be used as a test of the structure of new physics. If new physics is found at the LHC, then the many golden measurements from SuperB will help decode the subtle nature of the new physics. However if no new particles are found at the LHC, SuperB will be able to search for new physics at energy scales up to 10-100 TeV. In either scenario, flavour physics measurements that can be made at SuperB play a pivotal role in understanding the nature of physics beyond the Standard Model. Examples for using the interplay between measurements to discriminate New Physics models are discussed in this document. SuperB is a Super Flavour Factory, in addition to studying large samples of B u,d,s , D and τ decays, SuperB has a broad physics programme that includes spectroscopy both in terms of the Standard Model and exotica, and precision measurements of sin 2 θ W . In addition to performing CP violation measurements at the Υ(4S) and φ(3770), SuperB will test CPT in these systems, and lepton universality in a number of different processes. The multitude of rare decay measurements possible at SuperB can be used to constrain scenarios of physics beyond the Standard Model. In terms of other precision tests of the Standard Model, this experiment will be able to perform precision over-constraints of the unitarity triangle through

Hydrogen production from small hyropower sites. Final report

Energy Technology Data Exchange (ETDEWEB)

1980-04-01

A synergistic relationship was not found to exist between low-head hydropower and electrolytic hydrogen production. The storageability of hydrogen was expected to mitigate problems of hydrogen generation variability associated with the use of low-head hydropower as the power source. The expense of gaseous hydrogen storage equipment effectively eliminates storage as a means to decouple hydrogen demand and power/hydrogen production. From the opposite perspective, the availability of a low and stable cost of power from low-head hydro was expected to improve the competitiveness of electrolysis. In actuality, the results indicated that hydroelectric power from small dams would be comparatively expensive by current grid power standards (mid-1979). Electrolysis, in the capacity range considered here, is less sensitive to the cost of the power than originally presumed. Other costs including depreciation and capital related charges are more significant. Due to power generation variability, sole reliance on low-head hydropower to provide electricity to the cells would reduce the utilization of the hydrogen production investment, resulting in an increase in unit production costs. These factors were paramount in the Air Products recommendation to discontinue the study before continuing to more detailed stages of analysis, including an analysis of a site specific facility and the construction of a demonstration facility. Another major factor was the unavailability of a pipeline hydrogen supply situation which, because of lower distribution and capital costs, could have been commercially viable. An unfavorable judgment on the combined facility should not be misinterpreted and extended to the component systems. Although a detailed analysis of the individual prospects for electrolysis and low-head hydropower was beyond the study scope, the reader will realize, as the study is reviewed, that each is worthy of individual consideration.

Wave power integration with a renewable hydrogen energy system. Paper no. IGEC-1-085

International Nuclear Information System (INIS)

St. Germain, L.; Wild, P.; Rowe, A.

2005-01-01

In British Columbia, approximately 90% of the electricity generated comes from hydroelectric facilities while another abundant and renewable resource, ocean wave energy, is not being utilized at all. Technologies exist that can capture and convert wave energy but there are few studies examining systemic integration of wave energy devices. This work examines the potential to use wave energy as an input into a hydrogen-based renewable energy system. A model of an oscillating water column (OWC) was developed as a module within TRNSYS where it can be coupled to other existing hydrogen-specific components such as an electrolyser, storage device, and fuel cell. The OWC model accounts for device geometry, dynamics, and generator efficiency. For this particular study, wave profiles generated from hourly average data for a location on the west coast of Vancouver Island are used as a resource input. An analysis of the potential to utilise wave energy is carried out with an emphasis on overall system efficiency and resulting device scaling. The results of the integration of wave energy with other renewable energy inputs into a hydrogen-based system are used to make recommendations regarding technical feasibility of wave power projects on Vancouver Island. (author)

Behavior under irradiation of super-mirror for neutron guides

International Nuclear Information System (INIS)

N'Guy-Marechal, K.

1997-10-01

The aim of this work is to study the aging of NiCx/Ti super-mirror multilayers used in neutron guides under thermal neutron irradiation. These multilayers allow an increase of the apparent critical angle of total reflection by creating constructive interferences. Neutrons fluxes are thus increased in neutron guides made with a super-mirror coating. Thin films of one and ten bilayers have been deposited on a silicon and a borosilicate glass substrate. We have then studied the evolution of their optical, structural and mechanical properties after irradiation and annealing. After irradiation, a decrease in neutron reflectivity has been observed, due to the interdiffusion of both materials: this phenomenon was particularly important in the coatings deposited on a glass substrate. X-ray diffraction and X-ray absorption spectroscopy have shown that the structural evolutions of both nickel and titanium do not depend on the substrate. Nickel layers remain face-centered cubic after treatment, whereas the initially hexagonal closed-packed titanium becomes face-centered cubic with a texture in the [111] direction. This phase transformation has been attributed to the formation of a TiH compound containing as much as 50% hydrogen. Despite these structural changes, stress relaxation has occurred after irradiation in our layers. On the contrary, the mean stress that we have determined in previous samples, elaborated in another laboratory, has increased after irradiation. Comparison of both results shows that stress evolution is linked to the deposition conditions. As stress remains almost unchanged after annealing, we may conclude that only irradiation defects, and not heating, lead to stress evolution. Our samples being very similar to real neutron guides, we can extend the results we have obtained in this work to real super-mirrors. (author)

Primary energy sources for hydrogen production

International Nuclear Information System (INIS)

Hassmann, K.; Kuehne, H.M.

1993-01-01

The costs for hydrogen production through water electrolysis are estimated, assuming the electricity is produced from solar, hydro-, fossil, or nuclear power. The costs for hydrogen end-use in the power generation, heat and transportation sectors are also calculated, based on a state of the art technology and a more advanced technology expected to represent the state by the year 2010. The costs for hydrogen utilization (without energy taxes) are shown to be higher than current prices for fossil fuels (including taxes). Without restrictions imposed on fossil fuel consumption, hydrogen shall not gain a significant market share in either of the cases discussed. 2 figs., 3 tabs., 4 refs

Hydrogen: Adding Value and Flexibility to the Nuclear Power Industry

International Nuclear Information System (INIS)

Lee, J.; Bhatt, V.; Friley, P.; Horak, W.; Reisman, A.

2004-01-01

The objective of this study was to assess potential synergies between the hydrogen economy and nuclear energy options. Specifically: to provide a market analysis of advanced nuclear energy options for hydrogen production in growing hydrogen demand; to conduct an impact evaluation of nuclear-based hydrogen production on the economics of the energy system, environmental emissions, and energy supply security; and to identify competing technologies and challenges to nuclear options

Applications of the use of the renewable energies, solar power and wind power, for the securing of hydrogen, as power supply of the fuel cells; Obtencion de hidrogeno, a partir de la electrolisis del agua mediante energias renovables almacenamiento y aplicaciones

Energy Technology Data Exchange (ETDEWEB)

San Martin, J. J.; Martin, I.; Aperribay, V.; San Martin, J. I.; Arrieta, J. M.; Zuazua, J.; Romero, E.

2004-07-01

The object of the presented communication is to show the applications of the use of the renewable energies, particularly the solar power and the wind power, for the securing of hydrogen, as power supply of the fuel cells. The electrical energy produced in the solar badges and in the windpowers is, principally, injected into the electrical networks, for his transport, distribution and consumption, if the network the demand. The novel aspect is, that if the network does not demand potency, this one is transformed into hydrogen at the same photovoltaic station or into the base of the tower of the windpower and, later, stored to feed the fuel cells, not producing to him any type of element pollutant, since the residual element is the water. (Author)

Super Resolution Imaging of Genetically Labeled Synapses in Drosophila Brain Tissue.

Science.gov (United States)

Spühler, Isabelle A; Conley, Gaurasundar M; Scheffold, Frank; Sprecher, Simon G

2016-01-01

Understanding synaptic connectivity and plasticity within brain circuits and their relationship to learning and behavior is a fundamental quest in neuroscience. Visualizing the fine details of synapses using optical microscopy remains however a major technical challenge. Super resolution microscopy opens the possibility to reveal molecular features of synapses beyond the diffraction limit. With direct stochastic optical reconstruction microscopy, dSTORM, we image synaptic proteins in the brain tissue of the fruit fly, Drosophila melanogaster. Super resolution imaging of brain tissue harbors difficulties due to light scattering and the density of signals. In order to reduce out of focus signal, we take advantage of the genetic tools available in the Drosophila and have fluorescently tagged synaptic proteins expressed in only a small number of neurons. These neurons form synapses within the calyx of the mushroom body, a distinct brain region involved in associative memory formation. Our results show that super resolution microscopy, in combination with genetically labeled synaptic proteins, is a powerful tool to investigate synapses in a quantitative fashion providing an entry point for studies on synaptic plasticity during learning and memory formation.

Architectural Engineering to Super-Light Structures

DEFF Research Database (Denmark)

Castberg, Niels Andreas

The increasing global urbanisation creates a great demand for new buildings. In the aim to honour this, a new structural system, offering flexibility and variation at no extra cost appears beneficial. Super-Light Structures constitute such a system. This PhD thesis examines Super-Light Structures...... with architectural engineering as a starting point. The thesis is based on a two stringed hypothesis: Architectural engineering gives rise to better architecture and Super-Light Structures support and enables a static, challenging architecture. The aim of the thesis is to clarify architectural engineering's impact...... on the work process between architects and engineers in the design development. Using architectural engineering, Super-Light Structures are examined in an architectural context, and it is explained how digital tools can support architectural engineering and design of Super-Light Structures. The experiences...

Photosynthesis in Hydrogen-Dominated Atmospheres

Science.gov (United States)

Bains, William; Seager, Sara; Zsom, Andras

2014-01-01