Thorsteinn Sigfusson

Innovation Centre of Iceland

In this study, we have considered interaction between an aluminum oxide film magnetron-sputtered on commercially pure VT1-0 titanium and a hydrogen atmosphere. The time the system was exposed to hydrogen varied from 1 to 4 h with all other parameters remaining the same. Data for the distribution of hydrogen over the depth (film thickness) and its c...

The low energy excitation electronic states by the hydrogen atoms at the nonmetal surface are described using several possible mechanisms. The study results of the luminescence excited surface of the phosphor ZnS-Tm during interaction with H atoms are reported. Nonstationary with time the light intensity from ZnS-Tm is detected. This phenomenon int...

The phenomenological model of non-equilibrium diffusion and release of hydrogen from metals under the effect of electron beam in the sub-threshold region is considered. It is shown that the radiation stimulates the release and diffusion of hydrogen at a rate, significantly exceeds the rate of thermal equilibrium processes in the metals., This can o...

This is the history of a modern aluminum dross recycling company, from its beginnings in the last years of the twentieth century to the present day. The vision of the founders was to build a local recycling plant and take full responsibility for sensitive environmental issues by recycling aluminum dross locally rather than shipping it abroad. The p...

Self�propagating high�temperature synthesis (SHS) is applied for the production of porous sup� porting Ni–Al bases of solid�oxide fuel cells. The effect of synthesis conditions and the composition of source powders on the phase composition, microstructure, gas permeability, corrosion resistance, and other proper� ties of obtained Ni–Al samples is i...

We describe a method of obtaining anode-supported ZrO2:Y2O3 (YSZ) electrolyte films produced by reactive magnetron sputtering for intermediate temperature solid oxide fuel cell applications. A pulsed electron beam treatment was used as a method of preliminary modification of the porous structure in anode substrates. We studied the influence of this...

The paper reports scientific work performed at Tomsk Polytechnic University in Tomsk Russia and is a part of a larger project devoted to hydrogen technology. The aim of the work has been to develop Solid Oxide Fuel Cell membranes based on porous Ni-Al support and involving plasma technology for supplying the active substrate with active layers to b...

On the basis of results of the study, samples of chemically resistant track membranes have been obtained. The structure of the porous membrane has been formed via bombardment of a polyvinylidene fluoride (PVDF) film with 41-MeV argon ions followed by thermal pretreatment and chemical etching. The PVDF ion track membrane can be used for manufacturin...

Based on the analysis of our results and data available in the literature, it has been shown that the formation of self-similar tweed structures on (100)[001] aluminum single-crystal foils during constrained cyclic tension occurs under conditions of the Grinfeld instability. This is confirmed by the good agreement between the theoretical estimates...

The results of the manufacture and research of metal-supported solid oxide fuel cells are presented. As a metal support the porous Ni-Al plates manufactured by self-propagating high temperature synthesis were used. The effect of synthesis conditions and composition of green mixture on the phase composition, microstructure, porosity, gas permeabilit...

Ni-YSZ (YSZ - yttria-stabilized zirconia) films were fabricated by the reactive magnetron co-sputtering of Ni and Zr-Y targets. The maximum deposition rate was 6 μm·h-1. The oxygen flow and the DC power supplied to the Ni target were tuned to study the effect of the deposition conditions on the film properties and to obtain the film with required p...

We investigate the laws governing the saturation of nano- and coarse-crystalline Ti-6Al-4V alloy samples with hydrogen from high-frequency and glow discharge plasmas with a view to finding materials suitable for making hydrogen accumulators. We conclude that nanocrystalline Ti-6Al-4V alloy holds promise for creating hydrogen accumulators, and hydro...

Features of the temperature spectra of thermally stimulated gas evolution are investigated to determine features of the incorporation of hydrogen into titanium, palladium, and steel of 12Kh12M1BFR grade (metals substantially different with regard to hydrogen solubility) from media of various aggregate states. The conclusions are drawn with regard t...

A comparison of the temperature-time cycles of radical recombination luminescence (RRL) in atomic hydrogen, based on ZnS and ZnCdS at different partial pressures, is presented. The obtained results allow us to explain the temperature dependences of chemisorption of the charged form of N + and the optical transition rate upon RRL.

Renewable energy sources (RES) are in great demand and active research and development is now taking place globally to increase its share in total energy production. In Iceland the situation is somewhat unique because over 80% of the energy consumption in 2010 was from RES. Innovation Center Iceland has been an active contributor in research, devel...

The activation and diffusion losses in the redox reaction of iodide electrolyte of the Gretzel battery at the anode and cathode were examined. It was shown that the limiting diffusion current of the battery is limited by the diffusion mode of ion transport at the cathode or the anode depending on the composition of the electrolyte. In the case of a...

Hydrogen accumulation in samples of a palladium and 12Kh18N10T steel at the hydrogen charging by the electrolytic method and hydrogen release from these samples at its electron and X-ray irradiation are studied. Palladium was used as a comparison material (as most efficiently solvent hydrogen known among the simple materials). It is established tha...

The combustion process in air for aluminum nanopowders (nAl), micron-sized powders of aluminum (μAl), titanium (μTi) and zirconium (μZr) was accompanied by the predominant reaction of the metals with N2 and the subsequent stabilization of the nitride phases (from 38wt.% of ZrN for μZr combustion to 72wt.% of AlN for nAl combustion) in the condensed...

The influence of the diffusion zone width (parameter χ), which bounds the nucleation process in the nucleus neighborhood, on the dynamics of magma melt state at the initial stage of explosive eruption is numerically analyzed in the context of the Iordanskii-Kogarko-van Vijngaarden model of multiphase media. It is shown that in the region of 5 ÷ 50,...

The country of Iceland has become a world leader in renewable energy production based on the effective utilization of its natural resources. Iceland also articulated a vision of the "hydrogen economy" as a way to further reduce the import of fossil fuels. Iceland's practical experience with hydrogen and fuel cells has seen broader impact through in...

As a consequence of the increasing aluminum production in Iceland, local processing of aluminum skimmings has become a feasible business opportunity. A recycling plant for this purpose was built in Helguvik on the Reykjanes peninsula in 2003. The case of the recycling plant reflects increased concern regarding environmental aspects of the industry....

By a very simple experimental setup a rapid dissolution of basaltic material was demonstrated by injection of CO 2 into a mixture of deionized water and crushed tholeiite basalt lava at temperatures of 1°C, 25°C and 60°C during 1-5 weeks. The pH of the waters, originally at 3.6, stabilized at 4.9-5.8 depending on grain size of basalts, temperature...

By a very simple experimental setup a rapid dissolution of basaltic material was demonstrated by injection of CO2 into a mixture of deionized water and crushed tholeiite basalt lava at temperatures of 1°C, 25°C and 60°C during 1–5 weeks. The pH of the waters, originally at 3.6, stabilized at 4.9–5.8 depending on grain size of basalts, temperature a...

Hydrogen is one of the most sustainable, alternative energy sources that can play a significant role in reducing the detrimental environmental impact of fossil fuels. Every nation should combine their geothermal resources with hydrogen generation, to power transportation, and energy needs for transforming into fully hydrogen-based energy economies,...

When hydrogen is used as an alternative energy carrier, it is very important to understand the pathway from the primary energy source to the final use of the carrier. This involves, for example, the understanding of greenhouse gas emissions associated with the production of hydrogen and throughout the lifecycle of a given utilization pathway as wel...

The paper describes the background, motivations and action plan for an extensive experiment with hydrogen (H) as an energy carrier in Iceland. The energy consumption of Iceland is described as well as the role of fossil fuel imports in the otherwise renewable energy scenario. The paper goes on describing the academic/political reasons for the drive...

In Iceland there has been an official governmental aim to head towards a hydrogen society. In fact Iceland has been producing hydrogen for half a century by using alkaline electrolysis. The paper discusses the applicability of geothermal energy to the production, storage and use of hydrogen. After reviewing the vast geothermal resources of Earth a...

The intermetallic compound Ni3Al orders in the simple cubic (Cu3Au) crystal structure and becomes ferromagnetic below about 40 K with a spontaneous magnetization extrapolated to absolute zero and zero external magnetic field corresponding to approximately 0.075 μB/Ni atom. Measurements of the first magnetocrystalline anisotropy constant K1(T, H) ha...

Electrolysis at low temperature is currently used to produce Hydrogen. From a thermodynamic point of view, it is possible to improve the performance of electrolysis while functioning at high temperature (high temperature electrolysis: HTE). That makes it possible to reduce energy consumption but requires a part of the energy necessary for the disso...

From the time of the settlement of Iceland in the 9th century AD the use of wood and peat for fuel has put this resource in danger of exhaustion. For over two centuries the Icelandic industrial society has relied heavily on imported fossil fuels, coal, coke and petroleum. The abundant potential of Iceland regarding green power like hydroelectric an...

High-sensitivity de Haas-van Alphen (DHVA) measurements are reported for pure samples of Ni3Al in the temperature and magnetic field ranges 0.35<or=T<or=8K and 10<or=H<or=100 kG, respectively. Complex DHVA spectra consisting of up to 20 or more fundamental, harmonic and magnetic breakdown components are interpreted starting with two light and one v...

de Haas-van Alphen (DHVA) measurements have been carried out in fatigued copper crystals with average dislocation densities of approximately 1011 cm-2. The signals are unexpectedly large because the long-range strain fields of the individual dislocations are suppressed by correlations in their spatial distribution. This emphasises that dislocation...

Luminescence spectra of oxygen-rich propane gas flames have been recorded in medium-high resolution. Well-separated vibrational bands for electronic transitions in C2, CH, and OH are observed. The spectra are found to be rich in terms of both vibrational and rotational structure. Keywords (Audience): Upper-Division Undergraduate

The paper describes a path towards a future hydrogen energy economy in Iceland. The national energy situation is reviewed as well as production of hydrogen based fuels for transport and fishing sectors in Iceland by combining hydroelectric hydrogen and carbon oxides emission from metals industries. Finally the establishment of The Icelandic Hydroge...

There are new possibilities for transforming the ecological position of the metal-producing industries by utilizing their green-house gas emissions with electrolytically produced hydrogen to generate methanol as a replacement for gasoline.

High temperature Mssbauer spectroscopy has been used for studying “in situ” the phase dynamics of the silicon rich part of the binary Fe-Si system. In particular the rate and mechanism of the transformation of the so-called zeta-alpha phase of iron disilicide to the zeta-beta phase is of special interest, since there still remains uncertainty abou...

A numerical model of particle agglomeration in a fluid has been applied to TiB2 particles in liquid aluminium. The paper describes the theory behind the model and its solution method. The model is used to extend the understanding of inclusion behavior in liquid metal and computational results are compared with experimental results.

Total ozone measurements using a Dobson spectrophotometer have been performed on a regular basis at Reykjavík (64°08'N, 21°54'W), Iceland, since 1957. The data set for the entire period of observations has been critically examined. Due to problems related to the calibration of the instrument the data record of ozone observations is divided into two...

The Dobson station situated at Reykjavik (64 degree(s)08'N, 21 degree(s)54'W), Iceland is one of the few sites where a continuous long term monitoring of total ozone has been performed since the establishment of the Dobson network in 1957. A thorough analysis of the data has been performed with the aid of a statistical model which was developed to...

The paper presents some new concepts of hydrogen production in Iceland for domestic use and export. A brief overview of the Icelandic energy consumption and available resources is given. The cost of producing hydrogen by electrolysis is calculated for various alternatives such as plant size, load factors and electricity cost. Comparison is made bet...

In this work it is shown how the analysis of de Haas-van Alphen (dHvA) magnetic oscillations, traditionally performed with the use of fast Fourier transform (FFT), can be greatly improved by employing maximum entropy spectral analysis (MESA). In electronic systems where, for example, magnetic breakdown leads to close-lying dHvA frequencies of diffe...

A feasibility study exploring the use of geothermal energy in hydrogen production is presented. It is possible to use a thermal energy to supply heat for high temperature electrolysis and thereby substitute a part of the relatively expensive electricity needed. A newly developed HOT ELLY high temperature steam electrolysis process operates at 800 –...

Mssbauer spectroscopy has been used to determine the time-temperature-transformation diagram (TTT) for the eutectoid transformation in the silicon rich part of the Fe−Si binary system. Studies of TTT-diagram of samples consisting of 55 and 75 weight percent Si respectively have been carried out in nominally pure samples as well as commercial ones....

We present studies of phase dynamics of the silicon rich part of the Fe−Si system performed with Mössbauer spectroscopy. Standard spectra are obtained in very pure samples and these are applied to the studies of commercial 75& ferrosilicon. We find that the semistable high temperature alpha phase, known for considerable concentration of vacancies,...

A temperature modulation technique has been developed for magnetic measurements in solids. The paper outlines the basic principles of the method and the construction of apparatus for measurements of metals. Measurements of the temperature derivative of the magnetisation of the weak itinerant ferromagnet Ni 3 Al are reported. The field dependence of...

The first magnetocrystalline anisotropy constant K 1 (T,H) has been measured in stoichiometric single crystals of weakly ferromagnetic Ni 3 Al as a function of magnetic field in the range 1≲H≲48 kG at T=4.2 K and of temperature in the range 1.2≲T≲43 K at H=16 kG. At 4.2 K and 16 kG we obtain K 1 =-(9.6±0.7)10³ erg cm^-<sup>3</s...

The intermetallic compound Ni3Al orders in the simple cubic (Cu3Au) crystal structure and becomes ferromagnetic below about 40 K with a spontaneous magnetization extrapolation to absolute zero corresponding to approximately 0.075 μB/Ni atom. An investigation of parts of the Fermi surface has been carried out in stoichiometric single crystals by mea...

Power Chips Plc is in the final stages of developing solid-state thermal conversion devices that allow direct conversion of heat into electricity at 60-70% of Carnot efficiency. This is achieved by letting electrons tunnel across a gap of a few nanometers. Incorporating these devices into special purpose heat exchangers from Varmaraf allows large s...