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Currently, the use of secondary agricultural raw material is a topical issue. There are various applications of agricultural crop residues possible, but they are finance- and energy-consuming. Burning crop residues is very harmful for the environment. One of the ways to solve the problem is the production of solid biofuel that can be used to heat buildings. The authors suggest producing solid biofuel in the form of small-sized fuel rolls / pellets (SFR), which are made of oleaginous flax residues. As a result of the conducted experimental investigations, the authors have proved the efficiency and the environmental safety of SFR consumption. The new fuel can be recommended if the requirement of efficient and ecologically safe combustion is met. Thus, the influence of small-sized fuel rolls’ properties on the process of their combustion as well as quantitative and qualitative analysis of the combustion gases from burning solid fuel made of oleaginous flax residues have been investigated. The paper presents the results proving that SFR combustion is the most efficient on condition of providing reduced moisture (10-12%) and reasonable density (80 kg/m3) in the process of pellet production. In addition, it has been determined that there is a significant reduction of harmful CO emissions and normalization of СО2 concentration. The application of the suggested solid biofuel can make it possible to solve the problem of using oleaginous flax residues and provide cheap fuel for household purposes.

The membranes of vanadium alloys can be substantially more productive and much cheaper than the palladium alloy membranes which are widely used for hydrogen separation. However, the insufficient workability of vanadium alloys makes difficult producing the membranes of any shape, except for small thick flat samples, suitable only for laboratory studies, while membranes in the form of thin-walled tubes are most preferable for practical use. Such seamless thin-walled self-maintained membranes of tubular shape, made of V-Pd and V-Fe alloys with a thin Pd-coating on their inner and outer sides and with welded joints to stainless steel on both ends, were fabricated and tested for their throughput, service life, mechanical stability, and capability of hydrogen recovering from WGS mixtures. In view of reliable and highly productive operation of tubular V-alloy membranes as well as of their absolute selectiveness, the assembly from 18 membranes was fabricated to use it in the multi-fuel processor feeding a 1 kW PEM FC and providing up to 16 slpm of ultrapure hydrogen by the steam conversion of light and heavy hydrocarbons including diesel “Euro 5”. A similar assembly made of V-Fe alloy membranes was estimated for hydrogen purification in MOCVD applications.

The membranes of vanadium alloys can be a more productive and less expensive alternative to the membranes of palladium alloys for the extraction of ultrapure hydrogen. Alloying of V with Pd is very effective for the reduction of excessive hydrogen solubility inherent in pure V while the ductility of substitutional V-Pd alloys remains sufficient for making thin walled tubular membranes for practical applications. The hydrogen transport through the tubular membranes of substitutional V-κPd alloys with Pd coating of inner and outer sides was systematically studied with variation of alloy composition (0 ≤ κ ≤ 13.3 at%), temperature (300 – 500 °C) and pressure (0.001 – 1.2 MPa). The permeation flux density was almost independent of temperature for all investigated alloys. It was found that the main reason for this is the surface processes whose role dramatically increased with decreasing temperature, getting crucial at 300 °C. The record hydrogen diffusivity inherent in pure V reduced by alloying with Pd no more than 3 times even at the maximum degree of alloying (13.3%) and lowest temperature (300 °C). An assembly of 18 tubular membranes of V-5.2at%Pd with 145 µm wall thickness was designed for feeding 1 kW PEMFC and demonstrated a highly productive extraction of ultrapure hydrogen from WGS mixture.

Membrane technologies allow for significant simplification of the scheme of hydrocarbon conversion for obtaining ultrapure hydrogen to feed low-temperature fuel cells. However, commercially available membranes for hydrogen extraction utilize Pd alloys and therefore are expensive even while being not very efficient. Recently developed membranes of vanadium alloys demonstrate high efficiency combined with high practical utility. These features, for the first time, allowed for design and manufacture of a fuel processor prototype based on non-palladium membranes. 18 tubular-shaped membranes of vanadium alloy, 6 mm in diameter and 23.5 cm in length, were welded in a completely leakproof membrane system. This membrane system was integrated into a classic CH4 steam conversion scheme, which comprised a reformer followed by a single-step water gas shift reactor. The reformer was designed to convert 75% of CH4 to hydrogen, with the rest providing heat required for the reaction. At CH4 consumption of 6 slpm, steam-to-carbon ratio of 3, and total pressure of water–gas shift mixture of 1.2 MPa, the membrane system was extracting 80% of produced hydrogen, and as a result the fuel processor was providing 12 slpm of ultrapure hydrogen at 0.15 MPa to feed a 1 kW polymer electrolyte membrane fuel cell. As part of the fuel processor, the membrane system kept its initial throughput and perfect tightness through all the experimental process.

Despite the fastest transcrystalline transport of hydrogen in V, the application of pure V for the membranes permeable to hydrogen is problematic because of too large hydrogen solubility. The latter prevents from working at pressures of practical interest and obtaining a relevant permeation flux. To get a membrane material with optimal hydrogen solubility the substitutional V–Pd alloys with the content of Pd from 5 to 18.8 at% were studied with respect to hydrogen solution, diffusion and permeation in the pressure range from 0.02 to 1.2 MPa at 350 and 400 °C. Though Pd itself is a good occluder of hydrogen, the alloying of V with Pd suppressed the hydrogen solubility stronger than that is known with any other alloying elements while the hydrogen diffusivity was only slightly reduced. Hydrogen permeability was examined with plane and tubular membranes of the V–Pd alloys with thickness from 60 to 160 μm and surface area from 10 to 40 cm 2 . Both sides of the membranes were plated with Pd. Hydrogen permeability of the V–Pd alloys significantly exceeded that of Pd. The permeation flux density reached 0.7 scc/(cm 2 s) at a tolerable concentration of solute hydrogen when feed and permeate pressures of hydrogen were in the range of practical interest: ≈1 and 0.1 MPa respectively.

The development of non-palladium membrane for separation of hydrogen from gas mixtures is one of critical challenges of hydrogen energy. Vanadium based materials are most promising for such membranes. The alloying of pure vanadium is crucially important for reduction of hydrogen solubility to an optimal value. Solution of hydrogen in substitutional V- x Pd alloys ( x = 5, 7.3, 9.7, 12.3, 18.8 at%) was investigated. The pressure–composition-isotherms were obtained in the range of pressure (10–10 6 ) Pa, temperature (150–400) °С and concentration of hydrogen, H/M, from 4·10 −4 to 0.6. The alloying of vanadium with palladium was found to reduce the hydrogen solubility substantially greater than the alloying with other elements, e.g. by Ni and Cr. The hydrogen absorption in the V–Pd alloys obeyed Siverts' law including the range of undiluted solution with hydrogen concentration H/M > 0.1. The reduction in the hydrogen solubility due to the alloying of V with Pd was caused mainly by increase in the enthalpy of solution at nearly constant entropy factor. Changes in the gross electronic structure of metal are most probably responsible for the effects of alloying on the hydrogen solubility in the substitutional V–Pd alloys.

The composite membranes based on group 5 metals are capable of H2 separation with high speed and infinite selectivity. Hydrogen transport through Pd–V–Pd composite membranes of planar and tubular shape was investigated in the pressure range of (1×10−8–6×10−1) MPa at 400 °C. Due to the wide pressure range both the diffusion rate limited regime of hydrogen permeation and the regime limited by the H2 molecule dissociation were observed in one experiment. The density of flux permeating through the 100 µm-membrane reached 2.4 scc/(cm2 s) that seems to be one of highest ever achieved in the membranes based on group 5 metals as well as in any other unsupported metallic membranes. The concentration of dissolved hydrogen с Н / с V reached 0.42 but no noticeable reduction in hydrogen diffusivity was found. The constant value of sticking probability of H2 molecules (4×10−4) that was observed over full range of pressures used in this study indicates that the surface saturation has insignificant influence on the kinetics of boundary processes. The 100-fold cycling of hydrogen pressure from 0 to 0.6 MPa did not result in any loss of tubular membrane integrity and change of its shape despite the fact that the ductile-to-brittle transition occurred in each cycle. The operation with samples of planar and tubular shape demonstrated that V-based composite membranes can be used at least for laboratory studies. Further work to improve the long-term stability is necessary for their practical applications.

The composite membranes based on Group 5 metals are capable of H2 separation with the high speed and infinite selectivity. The chemical and thermal stability are critical issues for the application of such membranes in the field of hydrogen energy. In order to understand the degradation mechanisms, the H2 permeation through composite Pd2μm–Nb100μm–Pd2μm membranes was investigated in a very wide pressure range: (10−5–104) Pa. At higher pressures the surface contaminations only moderately decreased the permeation. However the permeation experiments at lower pressures demonstrated that an orders of magnitude change in the probability of H2 molecule dissociative sticking is actually hidden behind this relatively moderate effect. The membranes poisoned by the surface contaminations could be recovered by their exposure to O2 at (300–400) °C. Heating at temperature higher than 500 °C resulted in the irreversible decrease of permeation and in the pronounced change of permeation behavior at the variation of H2 pressure. An extremely high permeation was observed at lower pressures at the clean surface of Pd coating. That allows developing an effective membrane pump for hydrogen isotopes.

Hydrogen transport by 100-μm-thick vanadium and palladium membranes was studied in the pressure range from 1 × 10−8 to 4.5 × 10−1 MPa at a temperature of 400°C. Both sides of the vanadium membrane were covered by 2 μm of palladium (Pd-V-Pd) for facilitating the dissociative absorption and associative desorption of H2 molecules. At low pressures, hydrogen flux densities through vanadium and palladium membranes are nearly the same; at high pressures, the flux through the vanadium membrane becomes 16 times larger than the flux through the palladium membrane and attains a value of 2.4 scc cm−2 s−1. This flux of permeating hydrogen is larger than all values ever observed earlier for membranes made of group 5 metals or any other unsupported metal membranes.

The thermal stability of palladium-covered niobium, a composite used in hydrogen-tight membranes, is studied. Palladium is applied by the method of plasma sputtering. The thermal degradation of the coating is judged from a decrease in its ability to prevent niobium oxidation. It is found that the degree of oxidation of the samples heated in air at 693 K drops when the thickness of the coating increases in the range 2.5–1000.0 nm. The reason is heating-induced destructive modifications of the coating morphology, which are observed under a scanning electron microscope. The thicker the coating, the higher the temperature of onset of destruction. At temperatures above 873 K, the initially smooth continuous coating becomes highly porous and this porous layer does not change upon subsequent heating (up to 1273 K). Critical factors and possible mechanisms of thermal degradation of palladium coatings on hydrogen-tight composite membranes are discussed.

Group 5 metals (V, Nb and Ta) are potential candidates of tube material in vacuum permeator for tritium recovery from Pb-17Li liquid blanket system. From this viewpoint, the influence of oxygen on the surface reaction rates of hydrogen on V and Ta were examined in an ultra-high vacuum apparatuses at elevated temperatures, and the results were compared with the data on Nb acquired in a previous study. The surface reaction rates of hydrogen on V and Ta, and consequently permeation rates, decreased with increasing oxygen concentration in the bulk as previously observed for Nb. These observations were ascribed to the increase in surface oxygen coverage with increasing bulk oxygen concentration. The weakest influence of oxygen on hydrogen permeation rate was observed for V. The expected permeation rate through V under typical blanket conditions, however, was not necessarily high due to high oxygen solubility in V. The evaluation indicated that the highest permeation rate should be obtained with Nb under typical blanket conditions. (authors)

In order to understand the applicability of superpermeable membranes for tritium recovery from fusion exhaust gas containing impurities, the influence of oxygen and carbon on the performance of Nb and V membranes was examined by laboratory scale experiments. No significant degradation due to oxygen was observed if the membrane temperature was sufficiently high, i.e. above 700 K, and the bulk oxygen concentration was below 1.5 at.%. It was also possible to avoid the influence of carbon deposition by the operation at high temperatures through the conversion of carbon deposited layer into carbide layer.

The superpermeability phenomenon was suggested to use in fusion machines to separate the fuel mixture from helium ashes, to arrange in-vessel fuel recirculation contours and effective evacuation of...

The capability of a niobium panel to absorb atomic hydrogen was investigated for particle control application in divertors. The absorption rate (1.3 · 10 20 H/m 2 s) stayed almost constant up to a dose of 4 · 10 23 H/m 2 with no hydride formation occurring. The absorption panel can be easily regenerated. The absorbed hydrogen can be retained in the panel even after 48 h at room temperature. The absorption rate was found to decrease with panel temperature for T < 200 � C, remarkably dropping in the vicinity of room temperature. This is connected most probably with the formation of a multilayer impurity coverage. The multilayer carbon coverage deposited during the panel exposure in the divertor region of LHD decreased the absorption rate, but the panel properties could be completely restored by heating at 850 � C in spite of panel carbidization. � 2004 Elsevier B.V. All rights reserved.

The rate of oxygen removal from an oxygen-doped Nb membrane by hydrogen ion sputtering was examined by measuring the change in the sticking coefficient of H2, α. First, the temperature dependence of α was measured at various oxygen concentrations to investigate correlation between bulk oxygen concentration and α. Then the oxygen concentration in the membrane was adjusted to 1.5 at%, and the surface of the membrane was irradiated by hydrogen ions of 600 eV at 1113 K. The change in α with sputtering time was measured, and the reduction in bulk oxygen concentration was estimated from the extent of change in α. The oxygen concentration decreased with increasing sputtering time by continuous surface segregation of oxygen and sputtering. The sputtering yield of oxygen on the Nb membrane surface was evaluated to range from 0.012 to 0.036.

In view of benefits expected from the employment of membranes for particle control in fusion devices and for separation of hydrogen from its mixtures with hydrocarbons, the behavior of a Pd sample is investigated in a plasma-membrane device with a graphite target. The permeation of hydrogen through a 0.2 mm-thick Pd membrane with clean surfaces was found to be limited by the bulk diffusion. An incident flux of hydrocarbon radicals (approx. 2×10 12 cm -2 s -1 ) in hydrogen plasma forms no carbon layer on the Pd surface. Applying of a negative bias to the target gives rise to target sputtering, and to the deposition of carbon onto the membrane surface. The formation of carbon layer results in a decrease of the absorption probabilities of both H 2 molecules and H atoms. The effect of the deposition of carbon is found to depend non-monotonically on membrane temperature.

There are not a lot things that can be enjoyed by so many people as music. It is one of the few activities that crosses cultures, generations, social classes and languages. Music is also a natural part of marketing and is used in a variety of ways such as commercials, in-store music, brand collaborations and more. This report investigates the potential of Spotify’s music streaming platform for use in the field of marketing. Spotify has since its’ launch in 2006 grown to be one of the largest consumer streaming services, and publically launched a business orientated service in 2014. With a user base of over 40 million people, it is an interesting option for customer-brand interaction. To gather information, existing studies and literature were studied to gain a broader picture of the subject, a consumer study consisting of in-depth interviews and a case study was conducted to investigate possible ways of catering to consumers, and experts within the fields of commercial use of music were interviewed to gain relevant information as well as their views on the future of the subject. The outcome of this report is that brands have an opportunity to improve customer-brand relations by helping consumers to find new music, primarily through in-store music in physical retail environments, but further studies are needed to examine results of such activities. The execution depends on existing brand associations, type of brand as well as size and type of target consumers. In short, a playlist needs to be aligned to the brand in order to avoid mixed signals in communications, and attention needs to be paid to what not to play equally to what to play.

The article defines and proves the major financial and economical preconditions for the effective clusters' formation and functioning in Volyn' region. Based on the statistical data of the socio-economic development of Volyn' in 2012, a comprehensive analysis was made in order to determine the level of the region's readiness for the clusters' implementation process.

Niobium membrane was immersed in hydrogen plasma in order to study its interaction with hydrogen ions in the energy range from a few eV to 200 eV, controlled by changing the membrane bias. Degradation of plasma driven permeation (PDP) and enhancement of permeation driven by thermal molecules of cold gas (GDP) were observed when bias voltage was applied to the membrane exposed at plasma because of’ sputtering of non-metal impurity layer at upstream surface. Both dissolution of oxygen and increase of membrane temperature lead to decreasing of membrane bias effect due to rise of surface layer recovering rate.

A new apparatus was constructed to examine gas-, atom- and Plasma-driven permeation of hydrogen isotopes through group VA metal membranes with precisely controlled surface states. Absorption and desorption experiments are also possible. The new apparatus consists of two vacuum chambers, an upstream chamber and a downstream chamber, separated by a specimen membrane. Both chambers are evacuated by turbo-molecular pumps and sputter-ion pumps. The upstream chamber is equipped with Ta filaments serving as atomizers in atom-driven permeation experiments and cathodes in plasma-driven permeation experiments. The specimen membrane is formed into a tubular and electrically isolated from the chamber. Hence, ohmic heating of the membrane is possible, and this feature of the membrane is suitable for surface cleaning by high-temperature heating and impurity doping for the control of surface chemical composition through surface segregation. Both chambers were evacuated to 1x10-7 Pa after baking. The main component of residual gas was H2, and the partial pressures of impurity gases other than H2 were ca. 1x10-8 Pa. Gas- and atom-driven permeation experiments were successfully carried out with hydrogen gas for Nb membrane activated by heating in vacuum at 1173K. Superpermeation was observed in the atom-driven permeation experiments. Absorption experiments with a clean surface were also carried out. The surface was, however, cleaned only partially, because the temperature distribution was not uniform during high-temperature heating. Nevertheless, surface cleanliness was retained during absorption experiments under the present vacuum conditions. A new membrane assembly that will enable a uniform temperature distribution is now under construction.

A niobium membrane was immersed in hydrogen plasma and could be electrically biased to vary the energy of bombarding ions in the range of 1–200 eV. The fluxes of plasma driven absorption and permeation were almost entirely governed by incident suprathermal neutrals (mostly, thermal atoms), whose energy does not depend on membrane bias, but the ions of controllable energy do affect the neutral-induced permeation through modifying the membrane surface. At the zero bias a high temperature-independent plasma driven permeation (superpermeation) was observed alongside of an enhanced absorption. Bombardment by ions of an energy higher than 50 eV resulted in a sharp decrease of the plasma driven permeation/retention and in an acceleration of boundary processes of absorption/reemission of thermal molecules. At ion energies below 50 eV, the effect of ion bombardment on the plasma driven permeation and the kinetic coefficients of boundary processes were nonmonotonic in ion energy, having a maximum at ∼10 eV. Both an...

The effect of impurity (stainless steel (SS) components, carbon) deposition onto niobium membrane surface on the membrane permeability to hydrogen particles is investigated with a plasma device. The deposition of SS components onto the upstream surface of the membrane at the membrane temperature (TM)

A new divertor pumping system with superpermeable membranes of group Va-metals (Nb, V) is now under research and development. Properties of membrane pumping were investigated with the use of a plasma device simulating divertor plasma conditions. The deposition of metal (Fe) and non-metal (C) impurities on the membrane upstream surface results in a degradation of plasma driven superpermeation at the membrane temperature TmB 800°C, though the superpermeation regime is sustained at Tm] 800°C. The same temperature effect on superpermeation is observed at sputtering of membrane surface by energetic plasma ions. In addition, the first application of the membrane pumping to fusion devices has been carried out and a deuterium pumping through the membrane was demonstrated under the conditions of divertor plasma in the JFT-2M tokamak. © 2000 Elsevier Science B.V. All rights reserved.