Purkhart R.,IfU Diagnostic Systems GmbH |
Becher G.,BecherConsult GmbH |
Reinhold P.,Institute of Molecular Pathogenesis |
Kohler H.U.,Institute of Molecular Pathogenesis
Journal of Medical Microbiology | Year: 2017
Purpose. Differential ion mobility spectrometry (DMS) is an analytical technique used to detect volatile organic compounds (VOCs) in gaseous samples at very low concentration ranges from ppb to ppt. The aim of this study was to investigate whether VOC analysis by DMS is capable of detecting Mycobacterium avium subsp. paratuberculosis (MAP). Methodology. Headspaces of in vitro cultures of two different MAP strains at 1, 2, 3, 4 and 6 weeks after inoculation (each at two dilutions) were analysed with DMS in comparison to control samples without viable bacteria [(i) blank medium, (ii) medium inoculated with heat-inactivated MAP and (iii) sterile-filtered MAP culture broth]. Furthermore, VOC patterns in the headspace over cultures of six non-tuberculous mycobacterial species were compared to MAP-derived VOC patterns. Data analysis included peak detection, cluster analysis, identification of discriminating VOC features (Mann-Whitney U test) and different cross-validated discriminant analyses. Results. VOC analysis resulted in up to 127 clusters and revealed highly significant differences between MAP strains and controls at all time points. In addition, few clusters allowed differentiation between MAP and other non-tuberculous mycobacteria and even between different MAP strains. Compounds have not been characterized. VOC analysis by DMS was able to identify MAP-positive samples after 1 week of in vitro growth. Conclusions. This study provides strong evidence that VOC analysis of headspace over mycobacterial cultures in combination with appropriate data analysis has the potential to become a valuable method to identify positive samples much earlier than with current standard procedures. © 2017 The Authors.
Kelber C.,Institute For Produktionstechnik |
Marke S.,IfU Diagnostic Systems GmbH |
Trommler U.,CBS Information Technologies AG |
Rupprecht C.,TU Berlin |
Weis S.,Institute For Produktionstechnik
IOP Conference Series: Materials Science and Engineering | Year: 2017
Thermal spraying processes are becoming increasingly important in high-technology areas, such as automotive engineering and medical technology. The method offers the advantage of a local layer application with different materials and high deposition rates. Challenges in the application of thermal spraying result from the complex interaction of different influencing variables, which can be attributed to the properties of different materials, operating equipment supply, electrical parameters, flow mechanics, plasma physics and automation. In addition, spraying systems are subject to constant wear. Due to the process specification and the high demands on the produced coatings, innovative quality assurance tools are necessary. A central aspect, which has not yet been considered, is the data management in relation to the present measured variables, in particular the spraying system, the handling system, working safety devices and additional measuring sensors. Both the recording of all process-characterizing variables, their linking and evaluation as well as the use of the data for the active process control presuppose a novel, innovative control system (hardware and software) that was to be developed within the scope of the research project. In addition, new measurement methods and sensors are to be developed and qualified in order to improve the process reliability of thermal spraying. © Published under licence by IOP Publishing Ltd.
Bielousova O.,National School of Engineering, Saint-Etienne |
Kocimski J.,University of Windsor |
Maev R.G.,University of Windsor |
Smurov I.,National School of Engineering, Saint-Etienne |
And 2 more authors.
Surface Engineering | Year: 2016
One of the main specific features of the cold spray process is localisation during particle impact deformation. The resultant adiabatic shear instability is the phenomenon that is known to play a major role in the particle/substrate and particle/particle bonding and coating structure formation during the cold spray process. In this article, the cold spray process is numerically simulated as an impact between a single spherical particle with the substrate, and comparison with experimental results for Armco iron and stainless steel particles is made. To describe a deformation behavior of the two materials at high strain rates, the Johnson–Cook model has been chosen. The results indicate that the model accurately captures the grain distortion in the impact zone for both materials. This approach provides valuable information on the characterisation of the strain localisation at the particle/substrate interface. © 2016 Institute of Materials, Minerals and Mining.
Agency: European Commission | Branch: FP7 | Program: CP-FP | Phase: NMP.2010.1.2-4 | Award Amount: 4.04M | Year: 2010
Silver nanoparticles and silver based nanostructured composites are being frequently used in a variety of biomedical and industrial applications, such as an antimicrobial agents, lead-free solders, electric contact materials, gas-sensitive sensor, etc. The most complicated Silver using problems are related to: i) recovery of silver from ore waste materials; ii) the controlled synthesis of metal nanoparticles of well-defined size, shape and composition; iii) nanoparticles incorporation to desired implant surfaces; iv) synthesis of Silver based nanostructured composites for industrial purposes. The main goal of the Project is to develop: 1. Clean and efficient procedure of silver recovery from waste: Combined Mechanical Activation Thermal Oxidation Processing jarosite type residues to alleviate and accelerate the following precious metal leaching; 2. Combined nanotechnology of biological synthesis (use of plants for the nanoparticles synthesis) of Ag nanoparticles and its deposition on implant surfaces by electrophoretic and plasma spraying deposition; 3. Nanostructuring technology of Silver based nanocomposites manufacturing for electrical contact applications. Pilot production and trials of developed Ag nanoparticle modified implants and Ag based nanostructured composites: 1. TiO2 and Hydroxyapatite Ca10(PO4)6(OH)2) coated implants which are widely used in orthopaedic surgery because of their good biocompatibility related to the osteoconductive properties of calcium phosphate coating; 2. Ag-SnO contacts for electrical systems; these composites combine high resistance to welding and to electric arch erosion of the refractory phases with the high electric and thermal conductivities.
Ignatev M.,Instytut Obrobki Plastycznej |
Rybak T.,Instytut Obrobki Plastycznej |
Colonges G.,Projection Plasma Systeme |
Scharff W.,IfU Diagnostic systems GmbH |
Marke S.,IfU Diagnostic systems GmbH
Acta Metallurgica Slovaca | Year: 2013
Metallic silver, silver nanoparticles (AgNp) and nanocomposites based on silver are widely used in medicine, due to their antibacterial and antiseptic properties. The main goals of the present work were: (1) research of various types of liquids containing AgNp (including AgNp produced by biosynthesis technology using dessert plants (nopal, agave) extracts to reduce the silver); (2) research of sedimentation from liquids of AgNp on the surface of Hydroxyapatite (HA) implant coatings deposited by plasma spraying; (2) preliminary evaluation of antibacterial properties of HA coating modified with AgNp. The first test shows significant antibacterial activity of HA coatings containing AgNp produced by biosynthesis technology.
Voronov M.,Leibniz Institute for Solid State and Materials Research |
Hoffmann V.,Leibniz Institute for Solid State and Materials Research |
Wallendorf T.,IfU Diagnostic Systems GmbH |
Marke S.,IfU Diagnostic Systems GmbH |
And 5 more authors.
Journal of Analytical Atomic Spectrometry | Year: 2012
A novel Acousto-Optical imaging Spectrometer (AOS) was developed with unique features that make it attractive for different applications and fundamental investigations in atomic spectroscopy. Spatial resolution of the AOS is approximately 125 μm. Spectral resolution varies from 0.05 nm to 0.3 nm (full width at half maximum, FWHM) between 250 nm and 800 nm, respectively. Time resolution is 5 ns. Thus, the constructed AOS provides enough spatial, spectral and time resolution for applications in glow discharge imaging spectroscopy. Fast switching between different spectral lines within 200 μs can be used e.g. to investigate the evolution of different spectral lines quasi-simultaneously. © 2012 The Royal Society of Chemistry.