Blar i Department of Chemistry på dokumenttype "Doctoral thesis"
Viser treff 21-40 av 57
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Formic acid aided catalytic lignin conversion in ethanol and water media
(Doctoral thesis, 2016-12-21)The viability of future lignocellulosic bio-refineries is highly dependent on the efficient conversion of the lignin component. A promising and relatively new lignin conversion methodology is the Lignin-to-Liquid (LtL) ... -
From waste to bio-oil : Hydrothermal liquefaction of digested sewage sludge in small and large scale
(Doctoral thesis, 2023-06-16)FN’s bærekraftsmål er tydelige på hvilke tiltak som er nødvendige for å drastisk redusere de pågående klimaendringene i verden. Blant disse tiltakene finner man målet om bedre utnyttelse av bærekraftige råstoff, å sørge ... -
The influence of crude oil acids on natural inhibition of hydrate plugs
(Doctoral thesis, 2009-03-26)Gas hydrates can form in petroleum production systems of natural gas, water and crude oil. In some systems the hydrates agglomerate rapidly into large plugs that cause hazardous blockages of e.g. transport pipelines. The ... -
The influence of pipeline wettability and crude oil composition on deposition of gas hydrates during petroleum production
(Doctoral thesis, 2010-02-05)At specific temperature and pressure conditions, hydrates can sometimes plug production pipelines. It has been shown that some oils contain natural inhibiting compounds (NICs) that prevent hydrate plug formation even though ... -
Interpretation of chromatographic and mass spectrometric data from analyses of fatty acid methyl esters Application of multivariate methods
(Doctoral thesis, 2006-11-10)The purpose of this work has been to develop tools for fatty acid identification, with special emphasis on poly-unsaturated fatty acids and trans fatty acids. The work is based on application of gas chromatography with ... -
Investigation of the molecular and isotopic response to deposition, thermal maturity, hydrocarbon generation, and expulsion : A multidisciplinary approach based on the Cenozoic sequences on Svalbard
(Doctoral thesis, 2020-05-20)Understanding the generation, expulsion and migration of hydrocarbons and the associated effects on the molecular composition of generated products plays a major role in petroleum system analyses. The presented PhD study ... -
Isolation, identification and properties of pyranoanthocyanins and anthocyanin forms
(Doctoral thesis, 2007-06-22)This dissertation focuses on isolation and structural elucidation of anthocyanins, and their chemical properties. The characterization of anthocyanins from castor (Ricinus communis), fourteen cultivars of European gooseberry ... -
Large-scale conversion of lignin to liquid through formic acid assisted solvolysis in aqueous and ethanolic reaction media: comparison of yields and product compositions
(Doctoral thesis, 2020-01-17)Biomass has recently received much attention as an attractive renewable energy resource and a promising alternative to fossil carbon resources for production of renewable biofuels and other value-added chemicals due to ... -
Lineshape Models in Inner-shell Photoelectron Spectra of Free Molecules and Clusters
(Doctoral thesis, 2006-09-22)Investigating the nature of molecules and clusters is of paramount importance for our understanding of the composition and the properties of matter. X-ray photoelectron spectroscopy is one of the most powerful techniques ... -
Low Salinity Surfactant Flooding in Sandstone Cores
(Doctoral thesis, 2018-01-26)A new generation enhanced oil recovery (EOR) methods comes from combining techniques to make the overall process more efficient than either of the processes alone. These combined methods are often called hybrid EOR methods, ... -
Mechanistic Insight for Improved Catalytic Conversion of Fatty Acids to Linear α-Olefins : A Density Functional Theory Study
(Doctoral thesis, 2020-02-14)One of the greatest challenges in our time is the replacement of fossil fuels with more sustainable alternatives for energy and chemical production. Arguably one of the most important classes of petrochemical intermediates ... -
Mechanistic Modelling of Radial Polymer Flow in Porous Media
(Doctoral thesis, 2020-09-29)Polymer flooding is one of the most successful chemically enhanced oil recovery (EOR) methods, and has primarily been implemented to accelerate oil production by sweep improvement. However, research from the last couple ... -
A method for automated de novo design of functional transition-metal compounds
(Doctoral thesis, 2015-10-05)Systematic application of automated design methods in transition metal and organometallic chemistry is hampered by the limitations of computational tools traditionally developed according to organic chemistry formalisms. ... -
Multivariate analysis and modeling of crude oil composition and fluid properties relevant for Multiphase Flow Metering
(Doctoral thesis, 2014-09-05)Crude oil composition and properties have been subject for research for several decades, as well as the correlation between the chemical composition and physical properties of crude oil. The physical properties of crude ... -
Multivariate analysis of near-infrared spectroscopic data from reaction monitoring
(Doctoral thesis, 2003-12-17) -
N-Heterocyclic Carbene Complexes of Titanium vel Class of Catalysts for the Copolymerization of Cyclohexene Oxide with CO2
(Doctoral thesis, 2018-04-27)Regarding environmental, economic and political issues, the utilization of CO2 as C1 chemical feedstock has received a worldwide interest in the last decade. Indeed CO2 is considered as a greenhouse gas (submitted to strict ... -
Novel and colourful flavonoids - characterisation, secondary structures and properties
(Doctoral thesis, 2021-06-03)This dissertation focuses on isolation and structural elucidation of flavonoid pigments. The properties of these pigments have been explored, in terms of their chemical properties, especially regarding secondary structures ... -
Novel Synthetic Methodology and Total Syntheses of Highly Functionalized Carbazoles and Benzo[c]cinnolines
(Doctoral thesis, 2018-01-19)This dissertation discloses a project encompassing a synthetic strategies and new methods for the synthesis of some functionalized N-heterocyclic compounds. Much attention have been focused to synthesize N-heterocyclic ... -
Origin and character of gaseous hydrocarbons in the hydrate and non-hydrate charged sediments on the Norway - Svalbard margins
(Doctoral thesis, 2011-05-26)Gas incubated in clathrate water-structures, stabilizes the hydrogen bonded substance termed gas hydrate. In the marine environment vast amount of carbon is stored as gas hydrates within the temperature and pressure zone ... -
Phosphine- and Indenylidene-Based Z-Selective Ruthenium Olefin Metathesis Catalysts and Catalyst Stability: Decomposition, Olefin Isomerization and Regeneration
(Doctoral thesis, 2019-11-22)This thesis describes the development and synthesis of phosphine-bearing first-generation Z-selective olefin metathesis catalysts that give 70–95% of the Z-isomer product in homocoupling of terminal alkenes such as ...