Sökning: "w c ratio"

Visar resultat 11 - 15 av 37 avhandlingar innehållade orden w c ratio.

1. 11. CVD Chemistry of Organoborons for Boron-Carbon Thin Film Depositions

   Författare :Mewlude Imam; Henrik Pedersen; Jens Birch; Marrku Leskelä; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Boron-carbon thin films enriched with 10B are potential neutron converting layers for 10B-based solid state neutron detectors given the good neutron absorption cross section of 10B atoms in thin films. The common neutron-transparent base material, Al (melting point 660 °C), limits the deposition temperature and the use of chlorinated precursors forming corrosive by-products such as HCl. LÄS MER

3. 12. A Quantitative Thermogravimetric Study on the Nonevaporable Water in Mature Silica Fume Concrete: Influence of Carbonation and Moisture Conditions

   Författare :Elisabeth Helsing Atlassi; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; moisture; carbonation; cement composites; cement; thermogravimetric method;

   Sammanfattning : The primary goal of the project presented here was to study and quantify the influence of materials parameters (cement type, silica fume content, w/c ratio, type and dose of superplasticizers) and environmental parameters (carbonation and moisture history) on the nonevaporable water in hydrated cement composites. In order to achieve this, a thermogravimetric method which separates different types of nonevaporable water (bound in different hydrates and hydroxide) and carbonation products was developed. LÄS MER

4. 13. Investigations of the Kinetics of Reduction and Reduction/Carburization of NiO-WO3 Precursors

   Författare :Hesham M. Ahmed; Seshadri Seetharaman; Ricardo Morales Estrella; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reduction; Reduction-Carburization; Gas-solid Reactions; Kinetics; Hydrogen; Methane; Thermogravimetric analysis; Fluidized bed; Simulation; Thermal diffusivity; Thermal conductivity; Laser flash; Metallurgical process engineering; Metallurgisk processteknik; Process Metallurgy;

   Sammanfattning : Kinetic studies of reduction of the mixtures of NiO and WO3 having different Ni/(Ni+W) molar ratios in flowing hydrogen gas were investigated by means of Thermo Gravimetric Analysis (TGA), Fluidized Bed (FB) technique as well as Thermal diffusivity measurements under isothermal conditions. In the case of TGA, the reaction progress was monitored by mass loss, while evolved gas analysis by a gas chromatograph was the indicator of the reaction progress in the case of FB. LÄS MER

5. 14. Directed Energy Deposition Additive Manufacturing and Welding of Duplex Stainless Steel using Laser Beam

   Författare :Amir Baghdadchi; Leif Karlsson; Joel Andersson; Vahid Hosseini; Dirk Engelberg; Högskolan Väst; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Duplex stainless steel; Laser welding; Additive manufacturing; Direct Energy Deposition using a Laser Beam; Microstructure characterization; Duplexa rostfria stål; Lasersvetsning; Additiv tillverkning; Metalldeponering med laser; Mikrostruktur; Production Technology; Produktionsteknik;

   Sammanfattning : Duplex stainless steels (DSSs), with a ferritic-austenitic microstructure, are used in a wide range of applications thanks to their high corrosion resistance and good mechanical properties. However, efficient and successful production and joining of DSS require precise control of processes and an in-depth understanding of the relations between composition, processing thermal cycles, resulting microstructures and properties. LÄS MER

7. 15. Chemical vapour deposition of boron-carbon thin films from organoboron precursors

   Författare :Maiwulidan (Mewlude) Yimamu (Imam); Henrik Pedersen; Jens Birch; Carina Höglund; Erik Lindahl; Linköpings universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : Boron-carbon (BxC) thin films enriched in 10B are potential neutron converting layers for 10Bbased solid-state neutron detectors given the good neutron absorption cross-section of 10B atoms in the thin film. Chemical Vapour Deposition (CVD) of such films faces the challenge that the maximum temperature tolerated by the aluminium substrate is 660 °C and low temperature CVD routes for BxC films are thus needed. LÄS MER