Browsing NTNU Open by Author "Raaen, Steinar"
Now showing items 21-40 of 47
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Fabrication and Characterisation of Porous Coatings Enriched with Copper on CP Titanium Grade 2 under Plasma Electrolytic Oxidation
Rokosz, Krzysztof; Hryniewicz, Tadeusz; Gaiaschi, Sofia; Chapon, Patrick; Raaen, Steinar; Dudek, Lukasz; malorny, winfried (Journal article; Peer reviewed, 2019)In the present paper, coatings obtained on CP Titanium Grade 2 samples by Plasma Electrolytic Oxidation (PEO) in electrolyte containing concentrated phosphoric acid H3PO4 with copper nitrate Cu(NO3)2∙3H2O, are studied with ... -
Gold and Platinum Surface Nanostructures on Highly Oriented Pyrolytic Graphite
Karlsen, Terje Kultom (Master thesis, 2012)Self-assembled platinum and gold nanostructures, which are formed by evaporation and subsequent diffusion limited aggregation of metal on highly oriented pyrolytic graphite, have been studied by photoemission spectroscopy ... -
Gold Nanostructures on Graphite
Espeland, Erlend (Master thesis, 2013)Gold nanoparticles supported on a graphite substrate are prepared by thermal evaporation, and subsequently studied by X-ray photoelectron spectroscopy (XPS), temperature programmed desorption (TPD) of carbon monoxide and ... -
High-current-density electropolishing (HDEP) of AISI 316L (EN 1.4404) stainless steel
Rokosz, Krzysztof; Hryniewicz, Tadeusz; Rzadkiewicz, Slawomir; Raaen, Steinar (Journal article; Peer reviewed, 2015)The paper presents new XPS results of surface layers formed after electrochemical polishing of AISI 316L stainless steel at high current density (HDEP) of 1000 A/dm2 (EP1000) versus a standard electropolishing (EP50) process ... -
Impact of Gamma Irradiation on the Properties of Magnesium-Doped Hydroxyapatite in Chitosan Matrix
Predoi, Daniela; Ciobanu, Carmen Steluta; Iconaru, Simona Liliana; Predoi, Silviu Adrian Predoi; Chifiriuc, Mariana Carmen; Raaen, Steinar; Badea, Monica Luminita; Rokosz, Krzysztof (Peer reviewed; Journal article, 2022)This is the first report regarding the effect of gamma irradiation on chitosan-coated magnesium-doped hydroxyapatite (xMg = 0.1; 10 MgHApCh) layers prepared by the spin-coating process. The stability of the resulting 10 ... -
Influence of Elemental Carbon (EC) Coating Covering nc-(Ti,Mo)C Particles on the Microstructure and Properties of Titanium Matrix Composites Prepared by Reactive Spark Plasma Sintering
Biedunkiewicz, Anna; Figiel, Pawel; Garbiec, Dariusz; Obrosov, Aleksei; Pawlyta, Miroslawa; Biedunkiewicz, Witold; Pruss, Przemyslaw; Rokosz, Krzysztof; Wrobel, Rafal; Raaen, Steinar; Weiss, Sabine; Bokov, Dmitry (Peer reviewed; Journal article, 2021)This paper describes the microstructure and properties of titanium-based composites obtained as a result of a reactive spark plasma sintering of a mixture of titanium and nanostructured (Ti,Mo)C-type carbide in a carbon ... -
The Influence of Nanometals, Dispersed in the Electrophoretic Nanohydroxyapatite Coatings on the Ti13Zr13Nb Alloy, on Their Morphology and Mechanical Properties
Bartmanski, Michal; Pawlowski, Lukasz; Mielewczyk-Gryn, Aleksandra; Strugala, Gabriel; Rokosz, Krzysztof; Gaiaschi, Sofia; Chapon, Patrick; Raaen, Steinar; Zielinski, Andrzej (Peer reviewed; Journal article, 2021)In this work, nanohydroxyapatite coatings with nanosilver and nanocopper have been fabricated and studied. The presented results concern coatings with a chemical composition that has never been proposed before. The present ... -
Investigation of Spin Coating Cerium-Doped Hydroxyapatite Thin Films with Antifungal Properties
Iconaru, Simona Liliana; Predoi, Mihai Valentin; Chapon, Patrick; Gaiaschi, Sofia; Rokosz, Krzysztof; Raaen, Steinar; Motelica-Heino, Mikael; Predoi, Daniela (Peer reviewed; Journal article, 2021)In this study, the cerium-doped hydroxyapatite (Ca10−xCex(PO4)6(OH)2 with xCe = 0.1, 10Ce-HAp) coatings obtained by the spin coating method were presented for the first time. The stability of the 10Ce-HAp suspension particles ... -
Measurements of Young's Modulus on Rock Samples at Small Amplitude and Low Frequency: RockHard Deformations
Fintland, Trygve Westlye (Master thesis, 2011)This thesis describes a new instrumental approach designed to measure the complex Young s modulus on cylindrical samples 1 inch in diameter 2 inch long and typically in the range of 1-70 GPa. Excitation frequencies are ... -
Mechanisms Governing the occurrence of Partial Discharges in Insulation Liquids
Grav, Torstein (Master thesis, 2013)Breakdown of electrical equipment is unwanted and the use of reliable methods of insulation are therefore necessary. Liquid insulation is one preferred material for electrical devices used in subsea installations due to ... -
Metal Ions Supported Porous Coatings by Using AC Plasma Electrolytic Oxidation Processing
Rokosz, Krzysztof; Hryniewicz, Tadeusz; Raaen, Steinar; Gaiaschi, Sofia; Chapon, Patrick; Matysek, Dalibor; Pietrzak, Kornel; Szymanska, Monika; Dudek, Łukasz (Peer reviewed; Journal article, 2020)Coatings enriched with zinc and copper as well as calcium or magnesium, fabricated on titanium substrate by Plasma Electrolytic Oxidation (PEO) under AC conditions (two cathodic voltages, i.e., −35 or −135 V, and anodic ... -
Non-activated adsorption of methane on nickel surfaces induced by reduced work function
Raaen, Steinar; Hunvik, Kristoffer William Bø (Peer reviewed; Journal article, 2020)Adsorption of methane has been studied in ultrahigh vacuum environments on single crystalline as well as on Ni nano-particles on mica substrates. Experimental techniques have been X-ray and ultraviolet photoelectron ... -
Novel Porous Phosphorus–Calcium–Magnesium Coatings on Titanium with Copper or Zinc Obtained by DC Plasma Electrolytic Oxidation: Fabrication and Characterization
Rokosz, Krzysztof; Hryniewicz, Tadeusz; Gaiaschi, Sofia; Chapon, Patrick; Raaen, Steinar; Matysek, Dalibor; Dudek, Lukasz; Pietrzak, Kornel (Journal article; Peer reviewed, 2018)In this paper, the characteristics of new porous coatings fabricated at three voltages in electrolytes based on H3PO4 with calcium nitrate tetrahydrate, magnesium nitrate hexahydrate, and copper(II) nitrate trihydrate are ... -
Parallel Integration of Aligned Carbon Strings in Polymer Matrix: Dielectrophoretic Preparation, Electrical and Electromechanical Characterisation
Sandsaunet, Marit Ulset (Master thesis, 2012)Carbon black particles have been aligned into string-like assemblies by dielectrophoresis. Particles were dispersed in Dymax Ultra Light-Weld 3094 oligomermixture, with 0.1 vol.% filler content. This mixture was spread ... -
Partial Discharges on an Epoxy Surface due to Water Droplets
Grieg, Bernt Milne (Master thesis, 2011)Offshore wind turbines are exposed to a very harsh environment and can sustain significant damage during operation. In this thesis work, the possibilities of partial discharges in an insulation system of an offshore wind ... -
Phosphate Coatings Enriched with Copper on Titanium Substrate Fabricated Via DC-PEO Process
Rokosz, Krzysztof; Hryniewicz, Tadeusz; Kacalak, Wojciech; Tandecka, Katarzyna; Raaen, Steinar; Gaiaschi, Sofia; Chapon, Patrick; Malorny, Winfried; Matysek, Dalibor; Pietrzak, Kornel; Dudek, Lukasz (Peer reviewed; Journal article, 2020)The present paper covers the possible ways to fabricate advanced porous coatings that are enriched in copper on a titanium substrate through Direct Current Plasma Electrolytic Oxidation (DC-PEO) with voltage control, in ... -
Physicochemical and Biological Evaluation of Chitosan-Coated Magnesium-Doped Hydroxyapatite Composite Layers Obtained by Vacuum Deposition
Predoi, Daniela; Ciobanu, Steluta Carmen; Iconaru, Simona Liliana; Raaen, Steinar; Badea, Monica Luminita; Rokosz, Krzysztof (Peer reviewed; Journal article, 2022)In the present work, the effectiveness of vacuum deposition technique for obtaining composite thin films based on chitosan-coated magnesium-doped hydroxyapatite Ca10−xMgx(PO4)6 (OH)2 with xMg = 0.025 (MgHApCh) was proved ... -
Physicochemical mechanisms for gas adsorption on clay mineral interfaces and surfaces
Hunvik, Kristoffer William Bø (Doctoral theses at NTNU;2020:316, Doctoral thesis, 2020)Increasing anthropogenic carbon emissions have a detrimental impact on our planet's ecosystems. If we want to keep our planet habitable for future generations, serious action is needed. We need to both reduce and mitigate ... -
Porous Coatings Containing Copper and Phosphorus Obtained by Plasma Electrolytic Oxidation of Titanium
Rokosz, Krzysztof; Hryniewicz, Tadeusz; Kacalak, Wojciech; Tandecka, Katarzyna; Raaen, Steinar; Gaiaschi, Sofia; Chapon, Patrick; malorny, winfried; Matysek, Dalibor; Pietrzak, Kornel; Czerwinska, Ewa; Iwanek, Anna; Dudek, Lukasz (Journal article; Peer reviewed, 2020)To fabricate porous copper coatings on titanium, we used the process of plasma electrolyticoxidation (PEO) with voltage control. For all experiments, the three-phase step-up transformer withsix-diode Graetz bridge was used. ... -
Potential Oxide-Based Intermediate Band Materials: Fabrication and Photoemission Studies
Jorge, Marina Rodrigues (Doctoral theses at NTNU;2020:83, Doctoral thesis, 2020)Intermediate band solar cells (IBSCs) is a so-called third generation solar cell concept, and are based on a new type of semiconductor materials which have an intermediate band (IB) within the bandgap. This IB works as a ...