Browsing Fakultet for naturvitenskap (NV) by Title
Now showing items 12363-12382 of 12416
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X-ray absorption spectroscopic studies on active metal sites in zeotypes during the selective catalytic reduction of NOx with propene in an oxygen rich atmosphere
(Doktoravhandlinger ved NTNU, 1503-8181; 2005:130, Doctoral thesis, 2005)This thesis is concerned with the synthesis and characterisation of CuAPO-5, CuSAPO-5 and also copper ion-exchanged SAPO-5, SAPO-11 and ZSM-5. The ability of these materials to catalyse the selective reduction of NOx using ... -
X-ray absorption, X-ray diffraction and electron microscopy study of spent cobalt based catalyst in semi-commercial scale Fischer-Tropsch synthesis
(Peer reviewed; Journal article, 2014)Calcined, reduced and spent Co-Re/γ-Al2O3 catalysts for Fischer–Tropsch synthesis (FTS) were characterized and compared. Co-K-edge and Re-LIII-edge X-ray absorption near edge structure (XANES), X-ray powder diffraction ... -
X-ray Diffraction and Tomography Studies of Functional Organic Fibres
(Doktoravhandlinger ved NTNU, 1503-8181; 2013:74, Doctoral thesis, 2013)Structural characterisations of materials belong to the primary interests of basic and applied research, since they provide insights into the interactions of molecules and atoms, establish correlations with desired properties ... -
X-ray Microprobe Investigation of Iron During a Simulated Silicon Feedstock Extraction Process
(Peer reviewed; Journal article, 2016)Elemental silicon is extracted through carbothermic reduction from silicon-bearing raw feedstock materials such as quartz and quartzites. We investigate the micron-scale distribution and valence state of iron, a deleterious ... -
X-ray nanoscopy of a bulk heterojunction
(Journal article; Peer reviewed, 2016)Optimizing the morphology of bulk heterojunctions is known to significantly improve the photovoltaic performance of organic solar cells, but available quantitative imaging techniques are few and have severe limitations. ... -
X-ray Scattering Study of Nanostructured GaSb Surfaces
(Master thesis, 2013)In this thesis the surface structure of a sample consisting of slightly tilted, denselypacked Gallium-Antimonide (GaSb) nanocones, self-assembled through Ion Beam Sputtering(IBS) is investigated with a selection of X-ray ... -
X-ray Studies of Capture, Storage and Release of CO2
(Master thesis, 2012)We show experimentally that CO2 intercalates into the interlayer spaceof the synthetic smectite clay Li-fluorohectorite (LiFh). The intercalationoccurs for a range of conditions in terms of pressure (5 bar to 20 bar) ... -
X-ray Studies of Carbon Dioxide Intercalation in Na-Fluorohectorite Clay at Near-Ambient Conditions
(Journal article, 2012)We show experimentally that gaseous CO2 intercalates into the interlayer space of the synthetic smectite clay Na-fluorohectorite at conditions not too far from ambient. The mean interlayer repetition distance of the clay ... -
Xandarovula patula (Gastropoda: Ovulidae) new to Scandinavia
(Journal article; Peer reviewed, 2011)In August 2009 six specimens of the ovulid gastropod Xandarovula patula (Pennant, 1777) (formerly known as Simnia patula Pennant, 1777), were found in dredge samples from a locality west of Smögen in western Sweden (58°22′N ... -
XAS investigation of silica aerogel supported cobalt rhenium catalysts for ammonia decomposition
(Peer reviewed; Journal article, 2020)The implementation of ammonia as a hydrogen vector relies on the development of active catalysts to release hydrogen on-demand at low temperatures. As an alternative to ruthenium-based catalysts, herein we report the ... -
XPS and GDOES characterization of porous coating enriched with copper and calcium obtained on tantalum via plasma electrolytic oxidation
(Peer reviewed; Journal article, 2016)XPS and GDOES characterizations of porous coatings on tantalum after Plasma Electrolytic Oxidation (PEO) at 450 V for 3 minutes in electrolyte containing concentrated (85%) phosphoric acid with calcium nitrate and copper ... -
XPS Examination of the Oxide-Metal Interface of an Aluminum-Magnesium Alloy Containing Beryllium
(Chapter, 2018)The addition of beryllium to high magnesium aluminum alloys has long been known to cause a significant decrease in the rate of alloy oxidation. A clear understanding of the fundamental mechanism behind this effect is still ... -
Yb-Doped Fiber Lasers Operating in the Range of 1147-1200 nm
(Chapter, 2012)Pump source brightness and heat production per unit fiber length were found to be the critical parameters for the realized and investigated Yb-doped fiber lasers operating in the range of 1147-1200 nm. -
Yb-Tm energy transfer in Y-codoped fibers
(Chapter, 2013)Experimental investigation of Yb-Tm energy transfer process in Yb/Tm-doped fibers with Y-codoping provided a fairly high energy transfer efficiency of 50 %, making lasers based on these glass fibers attractive for diode-pumping ... -
YDFL Operating in 1150-1200-nm Spectral Domain
(Journal article; Peer reviewed, 2013)A family of high-power Yb-doped fiber lasers operated in the range of 1150–1180 nm with output powers of up to 35 W and optical efficiencies up to 60% is realized. Operation at 1200 nm is also demonstrated. Amplified ... -
Yield-increasing additives in kraft pulping: Effect on carbohydrate retention, composition and handsheet properties
(Doktoravhandlinger ved NTNU, 1503-8181; 2008:137, Doctoral thesis, 2008) -
Youngs's modulus of tumour tissue from an in vivo breast cancer model - effect of treatment with guluronate oligosaccharides
(Peer reviewed; Journal article, 2019)Increased tissue stiffness is a classic characteristic of solid tumours, and breast tumours are often first identified as a palpable lump. Increased tissue stiffness in tumours is more than just a typical, and often easily ... -
Yrkesfaglig praksis i bachelorutdanningen for yrkesfaglærere: En kartlegging av studentenes erfaringer
(Journal article; Peer reviewed, 2018)This study examines experiences of vocational teacher students in practice at work places. The aim is to develop and ensure that the practice is in accordance with the purpose of the Vocational Teacher Education programme ... -
Yttrium promoted Ni-based double-layered hydroxides for dry methane reforming
(Journal article; Peer reviewed, 2018)Yttrium modified Ni-based double-layered hydroxides were tested as novel catalysts in dry methane reforming. The catalysts were characterized by XRF, BET analysis, XRD, TPR-H2, TPD-CO2, TGA/DSC-MS, H2 chemisorption and ... -
Z2 characterization for three-dimensional multiband Hubbard models
(Peer reviewed; Journal article, 2020)We introduce three numerical methods for characterizing the topological phases of three-dimensional multiband Hubbard models based on twisted boundary conditions, Wilson loops, as well as the local topological marker. We ...