Hydrogen Research Papers - Academia.edu (original) (raw)

Reformer Tube Metallurgy: Design Considerations; Failure Mechanisms; Inspection Methods
Design principles
Recent developments in metallurgy
Failure mechanisms
Monitoring and inspection techniques

The charged quantum geometry of mass-ENERGY-Matter - developed from the foundational postulate that quantised angular momenta of Planck's constant is in fact reflective of an equilateral mass-energy geometry from which all 2d immaterial... more

The charged quantum geometry of mass-ENERGY-Matter - developed from the foundational postulate that quantised angular momenta of Planck's constant is in fact reflective of an equilateral mass-energy geometry from which all 2d immaterial EM fields and 3D material particles are created.

The WGS reaction is an exothermic reaction between carbon monoxide and steam to form carbon dioxide and hydrogen. This reaction, which has been used industrially for more than 100 years, has recently received a great deal of attention... more

The WGS reaction is an exothermic reaction between carbon monoxide and steam to form carbon dioxide and hydrogen. This reaction, which has been used industrially for more than 100 years, has recently received a great deal of attention from researchers as one of the ways to produce environmentally acceptable hydrogen from fossil fuels in large quantities. For the application of this reaction on an industrial scale, the key is choosing the optimal catalysts that can ensure high CO conversion and have a long lifetime under industrial conditions. Therefore, new types of catalysts are being developed that meet these requirements better than the Fe- and Cu-based catalysts commonly used in the past. The WGSR on a commercial nickel-based catalyst and a laboratory-prepared copper- and cobalt-based catalyst was tested in a laboratory apparatus set up at the University of Chemistry and Technology Prague. The best performance of the laboratory-prepared catalyst was observed for the catalyst wit...

The engineering correlations for assessment of hazard distance defined by a size of fireball after either liquid hydrogen spill combustion or high-pressure hydrogen tank rupture in a fire in the open atmosphere (both for stand-alone and... more

The engineering correlations for assessment of hazard distance defined by a size of fireball after either liquid hydrogen spill combustion or high-pressure hydrogen tank rupture in a fire in the open atmosphere (both for stand-alone and under-vehicle tanks) are presented. The term “fireball size” is used for the maximum horizontal size of a fireball that is different from the term “fireball diameter” applied to spherical or semi-spherical shape fireballs. There are different reasons for a fireball to deviate from a spherical shape, e.g., in case of tank rupture under a vehicle, the non-instantaneous opening of tank walls, etc. Two conservative correlations are built using theoretical analysis, numerical simulations, and experimental data available in the literature. The theoretical model for hydrogen fireball size assumes complete isobaric combustion of hydrogen in air and presumes its hemispherical shape as observed in the experiments and the simulations for tank rupturing at the g...

Three sources of halitosis exist, potentially in any combination: mouth, nasal cavity or alveolar breath. There has been no universally accepted protocol which differentiates and quantifies each odour source separately. In this study a... more

Three sources of halitosis exist, potentially in any combination: mouth, nasal cavity or alveolar breath. There has been no universally accepted protocol which differentiates and quantifies each odour source separately. In this study a new gas measurement protocol is described and tested to determine whether each odour source can be separately detected without contamination. Ninety healthy volunteers were divided into three groups. Hydrogen sulphide (H2S), volatile organic compounds (VOCs) and hydrogen (H2) were artificially generated in the mouth, nose and pulmonary alveoli, respectively. VOC, ammonia (NH3), sulphur dioxide (SO2), H2S and H2 gas readings from mouth, nose and alveolar air were measured and compared. Measurements were taken before and during gas generation. Contamination of nasal air (2.8%) and alveolar air (5.0%) by oral H2S; alveolar air (2.06%) and oral air (4%) by nasal organic gas; nasal air (18.43%) and oral air (9.42%) by alveolar H2 was calculated. The result...

Project funding and collaboration • Norwegian Research Council – Programme: RENERGI (Clean Energy for the Future) – 3 mill NOK granted for 3 years • Norwegian University of Science and Technology – Philosophical and Historical... more

The conversion of solar energy (SEC) to storable chemical energy by photosynthesis has been performed by photosynthetic organisms, including oxygenic cyanobacteria for over 3 billion years. We have previously shown that crude thylakoid... more

The conversion of solar energy (SEC) to storable chemical energy by photosynthesis has been performed by photosynthetic organisms, including oxygenic cyanobacteria for over 3 billion years. We have previously shown that crude thylakoid membranes from the cyanobacterium Synechocytis sp. PCC 6803 can reduce the electron transfer (ET) protein cytochrome c even in the presence of the PSII inhibitor DCMU. Mutation of lysine 238 of the Photosystem II D1 protein to glutamic acid increased the cytochrome reduction rates, indicating the possible position of this unknown ET pathway. In this contribution, we show that D1-K238E is rather unique, as other mutations to K238, or to other residues in the same vicinity, are not as successful in cytochrome c reduction. This observation indicates the sensitivity of ET reactions to minor changes. As the next step in obtaining useful SEC from biological material, we describe the use of crude Synechocystis membranes in a bio-photovoltaic cell containing ...

At the core of the "proton radius puzzle" is a four-standard deviation discrepancy between the proton root-mean-square charge radii () determined from the regular hydrogen (H) and the muonic hydrogen (µp) atoms. Using a... more

At the core of the "proton radius puzzle" is a four-standard deviation discrepancy between the proton root-mean-square charge radii () determined from the regular hydrogen (H) and the muonic hydrogen (µp) atoms. Using a cryogenic beam of H atoms, we measured the 2S-4P transition frequency in H, yielding the values of the Rydberg constant= 10973731.568076(96) per meterand= 0.8335(95) femtometer. Ourvalue is 3.3 combined standard deviations smaller than the previous H world data, but in good agreement with the µp value. We motivate an asymmetric fit function, which eliminates line shifts from quantum interference of neighboring atomic resonances.

Hydrogen is an economical source of clean energy that has been utilized by industry for decades. In recent years, demand for hydrogen has risen significantly. Hydrogen sources include water electrolysis, hydrocarbon steam reforming, and... more

Hydrogen is an economical source of clean energy that has been utilized by industry for decades. In recent years, demand for hydrogen has risen significantly. Hydrogen sources include water electrolysis, hydrocarbon steam reforming, and fossil fuels, which emit hazardous greenhouse gases and therefore have a negative impact on global warming. The increasing worldwide population has created much pressure on natural fuels, with a growing gap between demand for renewable energy and its insufficient supply. As a result, the environment has suffered from alarming increases in pollution levels. Biohydrogen is a sustainable energy form and a preferable substitute for fossil fuel. Anaerobic fermentation, photo fermentation, microbial and enzymatic photolysis or combinations of such techniques are new approaches for producing biohydrogen. For cost-effective biohydrogen production, the substrate should be cheap and renewable. Substrates including algal biomass, agriculture residue, and wastew...

On 9 October 2009, the Lunar Crater Observation and Sensing Satellite (LCROSS) sent a kinetic impactor to strike Cabeus crater, on a mission to search for water ice and other volatiles expected to be trapped in lunar polar soils. The... more

On 9 October 2009, the Lunar Crater Observation and Sensing Satellite (LCROSS) sent a kinetic impactor to strike Cabeus crater, on a mission to search for water ice and other volatiles expected to be trapped in lunar polar soils. The Lyman Alpha Mapping Project (LAMP) ultraviolet spectrograph onboard the Lunar Reconnaissance Orbiter (LRO) observed the plume generated by the LCROSS impact as far-ultraviolet emissions from the fluorescence of sunlight by molecular hydrogen and carbon monoxide, plus resonantly scattered sunlight from atomic mercury, with contributions from calcium and magnesium. The observed light curve is well simulated by the expansion of a vapor cloud at a temperature of ~1000 kelvin, containing ~570 kilograms (kg) of carbon monoxide, ~140 kg of molecular hydrogen, ~160 kg of calcium, ~120 kg of mercury, and ~40 kg of magnesium.

This paper describes a vehicle simulation toolbox developed under Matlab® environment, which can be used to estimate the range of a vehicle battery, or a fuel cell/battery hybrid system. The model is function of mechanical and physical... more

This paper describes a vehicle simulation toolbox developed under Matlab® environment, which can be used to estimate the range of a vehicle battery, or a fuel cell/battery hybrid system. The model is function of mechanical and physical variables that depend not only on the vehicle but also on the ground. This toolbox can be extended to GPS tracking files by means of reading data file plug-ins. Even standard drive cycles can be simulated. Battery and hydrogen consumption, hydrogen storage tank level, battery state of charge, power consumption and fuel cell energy production, maximum range and maximum number of cycles for a real route can be determined. The model facilitates the prediction of the vehicle range and the hydrogen and energy consumption. Real route simulation gives a good approximation of the vehicle speed close to real-life services instead of using driving cycles that are quite arbitrary approximations to a real route.

Previous studies examining gasoline and hydrogen engines have typically focused on factors pertaining to air to fuel ratios, their effects on an ICE performance, combustion by-products produced during the ignition cycle and its subsequent... more

Previous studies examining gasoline and hydrogen engines have typically focused on factors pertaining to air to fuel ratios, their effects on an ICE performance, combustion by-products produced during the ignition cycle and its subsequent environmental effects. Alternatively, this study examines the ways in which a hydrogen engine cavitation can be enhanced by using a graphene coated layer on the cylinder combustion chamber walls. SEM micrographs for the coated surfaces' microstructure showed a uniform distribution of the graphene layer that was free from cavities and demonstrating little to no observable defects. The study's results also showed large improvements in the BTE and exhaust temperature with respect to BMEP performance. This further resulted in significantly low levels harmful gaseous emissions, with observable reductions in the emissions of CO, NOx, and hydrocarbon derived from gasoline and pure hydrogen fuel. These results are thus indicative of a significant improvement in the performance of this particular typology of engine, in contrast to other experimentation focus found in other studies.

For Abstract see ChemInform Abstract in Full Text.

Future energy technologies must be based on renewable sources of energy and they must be sustainable. This workshop will provide insight into unintended impacts of renewable energy and how they can be avoided. In order to steer away from... more

Future energy technologies must be based on renewable sources of energy and they must be sustainable. This workshop will provide insight into unintended impacts of renewable energy and how they can be avoided. In order to steer away from the pitfalls and unintended effects it is essential that necessary knowledge is present to the developers and decision makers engaged in renewable energy. This is where this workshop is valuable in its discussion of unintended health and environmental impacts of various renewable energy technologies.
The workshop give the participants an introduction the the concept of unintended consequences, in connection with renewable energy. Furthermore, several approaches to improve the understanding of these consequences and methods for predicting them, will be discussed. This will include the concepts of rebound effects and consequential life cycle assessments (LCA). The workshop will encompass presentations and discussions of results from cross-disciplinary research on implementation of the alternative fuels hydrogen, electricity and biodiesel in the transport sector, as well as the assessment of environmental impacts from the production of solar cells. This will also cover impacts of the use of nanotechnology and nanomaterials in the various energy technologies. In-dept focus will also be on the formation of nanoparticles during combustion of bio-blended diesel, and the toxic effects of these new emission components.

Catalytic reforming of methane using carbon dioxide as the oxidant (Eqn. 1) is a reaction of great interest for the production of synthesis gas (H2 + CO), since in addition to generating an important chemical feedstock it simultaneously... more

Catalytic reforming of methane using carbon dioxide as the oxidant (Eqn. 1) is a reaction of great interest for the production of synthesis gas (H2 + CO), since in addition to generating an important chemical feedstock it simultaneously consumes two greenhouse gases. There is particular interest, as well as significant challenges, in combining it with the generation of biogas (CH4 + CO2) through the anaerobic digestion of biomass, a process that is currently significantly underutilised.
CH4 + CO2 ⇌ 2H2 + 2CO (1)
Research into the generation of electricity by direct reforming of methane using carbon dioxide in solid oxide fuel cells has been steadily increasing over the last few years, with much of the focus on using nickel supported yttria stabilised zirconia anodes [1,2]. These materials, however, suffer from severe lifetime issues due to unwanted carbon deposition caused by side reactions (Eqns. 2 and 3) and limited tolerance to sulphur that result in deactivation and limit their commercial viability. This solid formation of carbon blocks catalytically active sites and disrupts fuel distribution at the anode as well as breaking anode micro structure eventually leading to cell failure.
CH4 ⇌ C + 2H2 (2)
2CO ⇌ C + CO2 (3)
An alternative approach to using conventional nickel cermet anodes is to use mixed oxide materials. However, typically such materials show low catalytic activity and poor selectivity towards synthesis gas formation, favouring total oxidation products. In this presentation we show a novel, hydrothermally synthesized perovskite material that reforms biogas with negligible levels of carbon formation regardless of excess methane in the reactant feed. This material has significantly lower tendency to form deleterious carbon without sacrificing reforming activity and has been shown to be catalytically stable for extended periods of time (Fig.1).

Mathematical modeling is a powerful tool for improving the performance of fuel-cell stacks. In the present work, a mathematical model has been developed to study the performance of a proton exchange membrane fuel cell (PEMFC) at different... more

Mathematical modeling is a powerful tool for improving the performance of fuel-cell stacks. In the present work, a mathematical model has been developed to study the performance of a proton exchange membrane fuel cell (PEMFC) at different operation variables. The effects of different operating parameters on the performance of PEMFC have been studied using pure hydrogen on the anode side and air on the cathode side. Results with different fuel-cell operating temperatures, different operating pressures and various combinations of these parameters have been obtained. The possible mechanisms of the parameter effects and their interrelationships are discussed. The modeling results compare well with the available experimental results. The comparison shows good agreement between the modeling results and the experimental data.