Browsing Institutt for materialteknologi by Issue Date
Now showing items 581-600 of 2540
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Effect of CuO doping in Bi0.5K0.5TiO3 - Development of Lead-Free Ferroelectric Materials
(Master thesis, 2015)Piezoelectric materials are currently used in a significant number of electronic applications, and lead-free piezoelectric materials have obtained much attention in the recent years. Bismuth potassium titanate (BKT) is a ... -
Aqueous tape casting and mechanical properties of La2NiO4 dense membranes
(Journal article; Peer reviewed, 2015)An environmentally friendly aqueous tape casting process for the fabrication of La2NiO4+δ membranes was developed using fine powders synthesized by spray pyrolysis. Green tapes with a thickness of 30–300 μm were obtained ... -
Ferroelectricity in the multiferroic hexagonal manganites
(Journal article, 2015)Since their discovery in 1963 the hexagonal manganites have consolidated their role as exotic ferroelectrics with astonishing functionalities. Their introduction as room-temperature device ferroelectrics was followed by ... -
Thermal Conductivity of A-site Cation-Deficient La-Substituted SrTiO3 Produced by Spark Plasma Sintering
(Journal article; Peer reviewed, 2015)During the last decade oxide-based thermoelectric materials have received increased attention due to their high stability and thermal robustness at high temperatures as well as the availability and nontoxic nature of a ... -
Methodology to analyse small silicon samples by glow discharge mass spectroscopy using thin wafer mask
(Peer reviewed; Journal article, 2015)Glow discharge mass spectrometry (GDMS) is widely used for trace element analysis of bulk solid samples. Thegeometry of the GD source limits the minimum size of the sample, which for the instrument used in this ... -
Alternating Current Corrosion of Aluminum
(Master thesis, 2015)Formation of wax and hydrates due to production stops is a well-known problem in the oil industry. Conventionally the pipelines are heated beyond a critical temperature to avoid this problem. This is done by a method called ... -
The effects of impurities on the properties of Cz-grown silicon for solar cells
(Doctoral thesis at NTNU;2015:61, Doctoral thesis, 2015)The crystalline silicon solar cell has been dominating the PV market since it was introduced in the 1950´s. About 90% of solar modules currently installed are based on crystalline silicon, with cost-effective and high ... -
Impurities in Ilmenite - Excess Iron
(Master thesis, 2015)During this master s thesis, batches of ilmenite with three different Fe/Ti-ratios were successfully synthesised. After synthesis, the batches underwent pre-oxidation, reduction with ThermoGravimetric Analysis (TGA), before ... -
Late-magmatic immiscibility during batholith formation: assessment of B isotopes and trace elements in tourmaline from the Land’s End granite, SW England
(Peer reviewed; Journal article, 2015)Quartz–tourmaline orbicules are unevenly distributed in the roof segment of the Land's End granite, SW England. This study shows that the orbicules formed from an immiscible hydrous borosilicate melt produced during the ... -
Sintering of sub-micron K0.5Na0.5NbO3 powders fabricated by spray pyrolysis
(Journal article; Peer reviewed, 2015)K0.5Na0.5NbO3 (KNN)-based ceramics are promising lead-free piezoelectrics, but processing of these materials is an ongoing challenge. Here, we present a spray pyrolysis route to highquality KNN-based powders. Fine-grained ... -
The Oxygen Evolution Reaction at Iridium-Ruthenium Oxide Catalysts for PEM Water Electrolysis
(Master thesis, 2015)A sustainable method for hydrogen production can be achieved with PEM water electrolysers. These are considered important for the transition to a society based on renewable energy production as they can be coupled with ... -
Major depressive disorder seven years after the conflict in northern Uganda: burden, risk factors and impact on outcomes (The Wayo-Nero Study)
(Journal article; Peer reviewed, 2015)Background Major depressive disorder (MDD) is a major public health burden in conflict areas. However, it is not known for how long and by how much the observed high rates of MDD seen in conflict settings persist into the ... -
Development of Hydrophobic Surfaces for Anti-Icing Applications - Steel Substrates
(Master thesis, 2015)Icing is a major problem for ships, airplanes, and wind turbines, among many other applications. To reduce or remove icing is extremely costly and is constantly in need of manpower. In this thesis the possibility of a ... -
On the energetics of cation ordering in tungsten-bronze-type oxides
(Journal article; Peer reviewed, 2015)Oxides with the tetragonal tungsten bronze (TTB) structure are well-known ferroelectrics that show a large flexibility both with respect to chemical composition and cation ordering. Two of the simplest compounds in this ... -
Permanent Effect of a Cryogenic Spill on Fracture Properties of Carbon Steel
(Master thesis, 2015)In this work, the permanent effect of a cryogenic spill on the fracture properties of carbon steel was investigated. The experimental work consisted of two main parts. The first part was the examination of a plate of ... -
Electrical conductivity and thermopower of (1-x) BiFeO3 - xBi(0.5)K(0.5)TiO(3) (x=0.1, 0.2) ceramics near the ferroelectric to paraelectric phase transition
(Journal article; Peer reviewed, 2015)Ferroelectric BiFeO3 has attractive properties such as high strain and polarization, but a wide range of applications of bulk BiFeO3 are hindered due to high leakage currents and a high coercive electric field. Here, we ... -
EBSD Microstructure Characterization of 9% Nickel Steel during In Situ Heat Treatment
(Master thesis, 2015)The austenite content in 9% Ni steel was investigated with EBSD during and after in situ heating to different temperatures in the two phase region of the phase diagram, after first obtaining a coarse grained HAZ using weld ... -
Microstructural design of CaMnO3 and its thermoelectric proprieties.
(Master thesis, 2015)Calcium manganate (CMO) is an n-type semiconductor with promising thermoelectric proprieties. Solid state synthesis was employed to synthesise the desired material in two phases: i) reduced rock-salt phase of CaO-MnO (ss) ... -
Diffusion of alkali metals in the first stage graphite intercalation compounds by vdW-DFT calculations
(Journal article; Peer reviewed, 2015)Diffusion of alkali metal cations in the first stage graphite intercalation compounds (GIC) LiC6, NaC6, NaC8 and KC8 has been investigated with density functional theory (DFT) calculations using the optPBE-vdW van der Waals ... -
LaNi5-assisted hydrogenation of MgNi2 in the hybrid structures of La1.09Mg1.91Ni9D9.5 and La0.91Mg2.09Ni9D9.4
(Journal article; Peer reviewed, 2015)This work focused on the high pressure PCT and in situ neutron powder diffraction studies of the LaMg2Ni9-H2 (D2) system at pressures up to 1,000 bar. LaMg2Ni9 alloy was prepared by a powder metallurgy route from the LaNi9 ...