Sartinska L.L.,Frantsevich Institute for Problems of Materials Science
Acta Materialia | Year: 2011
In this contribution recent results on catalyst-free synthesis of new structures consisting of boron nitride (BN) and carbon-boron nitride (C-BN) are presented. Light-induced heating of fine grained graphite-like h-BN powders and a h-BN-lamp black composite was performed. The new structures of BN and C-BN were produced in a flow of dried and purified nitrogen in an optical furnace. The structure and phase composition were studied by transmission electron microscopy, scanning electron microscopy, optical microscopy and X-ray diffraction. It was shown that the BN whiskers obtained consist of multiwalled nanotubes covered by a polycrystalline shell. The processes of synthesis, formation and growth of the nanostructures in an optical furnace were analyzed. A qualitative model of the formation and growth of BN nanotubes and whiskers based on the release of gas from the powders and evolution of bubbles is proposed. © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
Shtepliuk I.I.,Frantsevich Institute for Problems of Materials Science
Superlattices and Microstructures | Year: 2014
Numerical simulations of Zn1-xCdxO/ZnO- based resonant tunneling diode structures are presented, employing the transfer matrix formalism and the Tsu-Esaki model. The factors influencing on the effective electron mass of the two-dimensional electron gas in the Zn 1-xCdxO/ZnO heterointerface - a conduction band nonparabolicity, a quantum confinement and a polaron effect - were analyzed and evaluated. The simulated current-voltage characteristics show a strong dependence on a well width, a barrier thickness and an internal electric field induced by a spontaneous and a piezoelectric polarization. © 2014 Elsevier Ltd. All rights reserved.
Kovalchenko M.S.,Frantsevich Institute for Problems of Materials Science
International Journal of Refractory Metals and Hard Materials | Year: 2013
The rheological model of deformable, irreversibly compressible, porous body based on mechanics of continua, and creep theory of crystalline materials, is used to describe quantitatively the compaction of the tungsten and titanium carbides powders under pressure sintering in isothermal conditions. Densification of the porous body occurs under action of Laplace's pressure, generated by surface tension, and applied pressure. The estimated mean value of Laplace's pressure was determined to be 5.8 MPa for tungsten carbide and 7.2 MPa for titanium carbide. The densification kinetics of tungsten carbide in the sintering range of 2100-2500 C and titanium carbides in the sintering range of 2100-2700 C are controlled by the mechanism of nonlinear steady-state creep, which occurs at a rate proportional to the fourth power of stress in carbide matrix forming porous material. The estimated values of activation energy for the powder particle power-law creep rate are 591 kJ/mol for tungsten carbide and 573 kJ/mol for titanium carbide during the pressure sintering in initial and intermediate stages. These values indicate that a climb dislocation mechanism controlled the creep, and the values are consistent with the activation energies of bulk diffusion in metal sublattice of carbides. A diffusional creep controls the pressure sintering kinetics in a later stage. © 2013 Elsevier Ltd. All rights reserved.
Brus V.V.,Frantsevich Institute for Problems of Materials Science
Solar Energy | Year: 2012
A simple approach for the calculation of the width of the space charge region (and consequently the concentration of uncompensated acceptors), which takes into account the effect of the series resistance on the quantum efficiency of anisotype asymmetrical thin film heterojunction solar cells (on the example of CdS/CdTe solar cells), was proposed. The effect of the light dependent series resistance and current transport mechanism was also taken into consideration. © 2011 Elsevier Ltd.
Brus V.V.,Frantsevich Institute for Problems of Materials Science
Solar Energy | Year: 2012
A new technique is proposed for the calculation of the width W of space charge region and consequently the concentration of uncompensated acceptors N A-N D, which is based on the open-circuit analysis of thin film heterojunction solar cells illuminated by monochromatic light with the wavelength within photosensitivity region. The proposed method was simulated under different values of the theoretically considered parameters (ideality coefficient n, saturation current I 0 and shunt resistance R sh) of a CdS/CdTe heterojunction solar cell. The calculated values of W and N A-N D were established to be dependent on the mentioned above electrical parameters. © 2012 Elsevier Ltd.
Agency: European Commission | Branch: FP7 | Program: CP-IP | Phase: NMP.2013.2.1-1 | Award Amount: 8.12M | Year: 2014
Innovative processes with streamlining and improved control will be conducted in FIBRALSPEC, through Unit for Continuous PAN-based Carbon Fiber Pilot Production. Testing of laminates and prepregs production based the new developed carbon fibres followed by manufacturing of laminates/coupons and high-performance filament wound tubes are also foreseen (equipment for delivering precise volumes the matrix (resin) in high and low-capacity to impregnate the fibres and bundles will be developed). The project also efforts on functionalization will be mainly focused on cost reduction, mechanical and chemical property improvement. Novel CF precursors will be developed (silicon carbide, textile-grade PAN, polyolefins, and lignin); in parallel, the suitability of a new environmentally friendly pitch will be assessed, obtained from anthracene oil, for the preparation of isotropic carbon fibres. The projects carbon fiber conversion technology will pyrolysis process to convert PAN precursor fiber into PAN-based carbon fiber and activated carbon fiber. Innovative surface treatment will improve the step of treatment of the carbon fiber surface being indispensable for productions in series. As for recycling and used of recycled CFs, new techniques will be used to provide commercially-relevant products that are manufactured from waste carbon fibres. Mathematical modeling will be conducted so as to determine properties of CFs and composites, together with cost modeling; life cycle assessment will assist in possible commercial risks that will be continuously estimated during the project and quantify/assess the environmental impact of the materials that will be used. Industrial partnership will ensure the impact of the research efforts, convincingly proving scalability towards industrial needs of two high demanding applications, namely medium technology large scale (Rapid Deployment Secure Emergency Shelter (RDSES)) and high technology small scale (supercapacitor).
Agency: European Commission | Branch: FP7 | Program: CSA-SA | Phase: AAT.2008.7.0.6. | Award Amount: 210.16K | Year: 2009
Ukraine has a proud heritage in aeronautics dating from the Soviet era. It is one of the few countries in the world to have research, engineering and production capabilities across a wide range of aeronautics technologies. Despite these strengths, the participation of Ukrainian aeronautics actors in the ECs research framework programmes is very low (e.g. only 4 contracts were won under FP6-AEROSPACE). Consequently, the main aim of AERO-UKRAINE is to facilitate research co-operation between aeronautics actors from the EU and Ukraine. The project will achieve this via a range of activities: 1. Assessing and publicising the aeronautics collaboration potential between the EU and Ukraine. This involves mapping the Ukrainian aeronautics actors; reporting on opportunities for Ukrainian aeronautics actors in the EU; and production of a White Paper on aeronautics R&D in the Ukraine; 2. Raising awareness and understanding of EU aeronautics collaborative research. On the one side, this involves organising FP7 aeronautics events in Ukraine that combine awareness-raising, training and networking with EU aeronautics actors. On the other side, it involves Ukrainian aeronautics actors presenting their aeronautics research at aeronautics events in the EU; 3. Supporting participation in FP7 aeronautics research. This involves establishing an FP7 Aeronautics NCP in Ukraine and supporting Ukrainian aeronautics organisations to join consortia preparing FP7 research proposals. AERO-UKRAINEs measurable results include: a. White Paper on aeronautics R&D in the Ukraine; b. Website and publicly available information about 50\ aeronautics actors in Ukraine; c. Organisation of 2 FP7 aeronautics events in Ukraine; d. Participation in 3 aeronautics events in the EU; e. Establishment of an FP7 Aeronautics NCP in Ukraine; f. Support to 6\ Ukrainian aeronautics actors to join consortia preparing FP7 research proposals; g. Organisation of final dissemination conference in Kiev.
Agency: European Commission | Branch: FP7 | Program: CSA-SA | Phase: NMP.2013.4.0-5 | Award Amount: 631.96K | Year: 2013
NANOMAT-EPC aims to support the deployment of societally beneficial nano- and materials technologies in European Partnership countries (EPC), in order to increase exploitation of their scientific results and contribute to the United Nations Millennium Development Goals. Consequently, NANOMAT-EPC aims to develop knowledge and technology transfer in nano- and materials technologies for healthcare, clean energy and environment applications. The project will be implemented by a well-balanced consortium of nine partners four EPC partners and five EU partners. In order to stimulate the knowledge and technology transfer, NANOMAT-EPCs mission is the following: i. Map and promote organisations involved with nano- and materials technologies in EPC; ii. Organise brokerage events in the EPC to facilitate knowledge and technology transfer in nano- and materials technologies; iii. Organise workshops in the EPC to identify nano- and materials knowledge and technology transfer opportunities; iv. Implement pilot nano- and materials technologies deployment projects. The pilot projects will be bilateral between the EPC and European partners and based on education, training and exchange of scientists as follows: a. Deployment of high conductivity zirconia anodes in solid oxide fuel cells (IPMS and UB) b. Deployment of hybrid CNT/graphene electrodes for supercapacitors (BSUIR and Cleancarb) c. Deployment of nanosensory devices for environmental monitoring using picosecond laser technology (GTU and PSUD) d. Deployment of magnetic nanoparticles for medical applications (IPR-NAS and LZH) v. Produce report with recommendations on how to exploit to nano- and materials knowledge and technology transfer opportunities in EPC.
Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: SPA.2013.3.2-01 | Award Amount: 2.74M | Year: 2014
LIGHT-TPS will develop a new super-light Thermal Protection System (TPS) for various space applications, above all for Reusable Space Systems (RSS), capable of operating within the entire range of working temperatures. The project aims at radical properties improvements in the TPS used existing and under-development RSS. The main disadvantage of existing TPS based on metallic frames is the significant weight and insufficient lifetime, due to the degradation and corrosion of the metal. A class of materials, commonly referred to as ultra-high temperature ceramics (UHTC) possesses a unique combination of physico-chemical properties that makes them specifically suited for application in aerospace sector. The UHTC-based coating that will be developed will provide superior oxidation protection to metal alloys, as well as to light constructions made of C/SiC and C/C materials. The main challenge of the project is to develop a super-light, corrosion and oxidation resistant TPS by combining the advantages of metallic and ceramic materials in a single system. This will be achieved by joining a novel metallic frame with non-metallic materials (for example C/SiC and C/C), construction elements made of UHTC (system ZrB2-SiC) and new high-temperature alloys coated with UHTC composites. Particularly, the 3 direction of works are envisaged: 1) development of new powder alloys on the base of Ni/Cr and Nb for the frame of TPS; 2) development of reusable light weight multilayer metallic TPS sandwiches; 3) investigation of erosion-resistant UHTC bulk materials in the ZrB2-SiC system and coating of metallic and non-metallic materials with the most suitable UHTC compositions. The developed TPS will be significantly lighter than any existing TPS (under 10 kg/m2) thus reducing the cost of delivering a payload to orbit and volume of emission, guarantee reliable thermal protection in the entire range of working temperatures, possess improved mechanical and durability properties.
News Article | April 26, 2016
The European Commission is to support the Functionalized Innovative Carbon Fibers Developed from Novel Precursors with Cost Efficiency and Tailored Properties (FIBRALSPEC) four-year project, run by the National Technical University of Athens (NTUA), Greece. FIBRALSPEC has been co-financed by the European Union’s 7th framework programme (2007- 2013) to €6.08 million. It focuses on conducting innovative processes with streamlining and improved control through a unit for continuous PAN-based carbon fiber pilot production. This includes testing of laminates and prepregs production based on the new developed carbon fibers, followed by manufacturing of laminates/coupons and high- performance filament wound tubes. Efforts are also dedicated to the surface, functionalization, cost reduction and improvement of the fibers’ mechanical and chemical properties. The project is also investing in new techniques to make commercially-relevant products made from waste recycled carbon fibers. The other partners in the project are Politechnico di Torino, Italy, University of Birmingham, United Kingdom, Thales research and technology, France, Global Safeguard Ltd, United Kingdom, Open source management Ltd, United Kingdom, Anthony, Patrick & Murta Exportação, Portugal, Frantsevich Institute for Problems of Materials Science, Ukraine, CTM Equipment Limited, United Kingdom, Yuzhnoye SDO, Ukraine and Euromobilita sro, Czech Republic. ‘The project builds upon the experience gained and will result in upcoming breakthrough innovations, through challenges and goal achievements,’ project coordinator Prof Costas A Charitidis says. This story is adapted from material from FIBRALSPEC, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier.