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norskFakultet for naturvitenskap og teknologi: Recent submissions
Now showing items 4241-4260 of 5439
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ASM Microbe 2016
(Journal article; Tidsskriftartikkel, 2016-09-12) -
An evaluation of International Reference Ionosphere electron density in the polar cap and cusp using EISCAT Svalbard radar measurements
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-09-13)Incoherent scatter radar measurements are an important source for studies of ionospheric plasma parameters. In this paper the EISCAT Svalbard radar (ESR) long-term database is used to evaluate the International Reference Ionosphere (IRI) model. The ESR started operations in 1996, and the accumulated database up to 2012 thus covers 16 years, giving an overview of the ionosphere in the polar cap and ... -
Study of Wind Chill Factor using Infrared Imaging
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-29)This paper presents a study of wind chill factor using infrared imaging. Wind chill factor is the cooling sensation due to the exposure of wind temperature environment. The wind chill factor depends on air temperature, wind velocity, and humidity. Wind chill poses serious health risks. Various wind chill index models are given in the literature. The wind chill factor is closely associated with the ... -
Multiphysics Simulation of Infrared Signature of an Ice Cube
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-29)This paper presents numerical methodologies to simulate the Infrared (IR) signature of an ice cube. The ice was frozen in a cold environment (-28<sup>o</sup>C) and allowed to have uniform temperature throughout. It was then taken out and let to warm at room temperature conditions by means of natural convection. A 3D transient heat equation is solved using three different methodologies. In the first ... -
Review of the Phenomenon of Ice Shedding from Wind Turbine Blades
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-29)Wind power is a sustainable source of energy. However, there are certain challenges to be overcome. One of the operational challenges is the phenomenon of ice shedding. Icing happens on wind turbine blades in cold regions. When ice grows to a certain size, it separates from the wind turbine blades resulting in the phenomenon of ice shedding. This phenomenon is of significantly dangerous for equipment ... -
Investigation of Ice-PVC separation under Flexural Loading using FEM Analysis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-29)This paper presents the FEM technique applied in the study of ice separation over a polyvinyl chloride (PVC) surface. A two layer model of ice and PVC is analysed theoretically using Euler-Bernoulli beam theory and the rule of mixtures. The physical samples are prepared by freezing ice over the PVC surfaces. The samples are tested experimentally in a four-point loading setup. The experimental results ... -
Determination of Thermal Properties of Fresh Water and Sea Water Ice using Multiphysics Analysis
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-29)This paper presents a methodology to determine the thermal conductivity of ice using multiphysics analysis. This methodology used a combination of both experimentation and numerical simulation. In the experimental work, an ice block is observed using an infrared camera. The results reveal the variation in temperature over the surface. These results are dependent on two primary heat transfer parameters, ... -
Total synthesis of tubastrine and 3-dehydroxy tubastrine by microwave-assisted cross-coupling reactions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-09-03)The first syntheses of tubastrine and 3-dehydroxy tubastrine are described. The target compounds were prepared in four consecutive steps from commercially available starting materials. The central scaffold was formed by a microwave-assisted C–N cross-coupling reaction between 1,3-bis(<i>tert</i>-butoxycarbonyl)-guanidine and (<i>E</i>)-((4-(2-iodovinyl)-1,2-phenylene)bis(oxy))bis(<i>tert</i>-butyl ... -
Palladium(0)-Catalyzed Cross-Couplings of 2-Bromophosphinine
(Journal article; Tidsskriftartikkel; Peer reviewed, 2013-05-21)A new Negishi-type cross-coupling of 2-bromophosphinine has been developed. The new method expands the scope of palladium-catalyzed couplings to monobromophosphinines, which have been considered as poor substrates so far. Moreover, aryl-, alkenyl-, and alkynylzinc bromides were found to be effective coupling partners. -
Calculating molecular properties in realistic environments
(Doctoral thesis; Doktorgradsavhandling, 2016-05-13)This thesis focuses on how absorption properties of molecules are influenced by their environment and how this can be calculated accurately. Calculations have been performed with a polarizable embedding (PE) multiscale model. The environment is described classically by charges and electric multipoles for the permanent electrostatics and polarizabilities for polarization interactions. Density-functional ... -
Experimental and four-component relativistic DFT studies of tungsten carbonyl complexes
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-07-24)We present a theoretical and experimental study of the structure and nuclear magnetic resonance (NMR) parameters of the pentacarbonyltungsten complexes of η<sup>1</sup>-2-(trimethylstannyl)-4,5-dimethylphosphinine, η<sup>2</sup>-norbornene, and imidazolidine-2-thione. The three complexes have a pseudo-octahedral molecular structure with the six ligands bonded to the tungsten atom. The η<sup>1</sup ... -
Paleoceanographic development in Leirdjupet, during the last deglaciation
(Master thesis; Mastergradsoppgave, 2016-08-23)The focus of this master thesis is to investigate the paleoenvironmental and paleoceanography during the last deglaciation in Leirdjupet, a small submarine trough in the southwestern Barents Sea. The lower half of the piston corer HH15-1303PC has been investigated for the distribution pattern of benthic foraminifera faunas, ice rafted debris (IRD), lithology and oxygen and carbon isotopes covering; ... -
Reconstructions of paleoceanography and ice retreat based on benthic foraminifera, stable isotopes and sedimentological investigations from the northwestern Barents Sea south of Nordaustlandet, Svalbard
(Master thesis; Mastergradsoppgave, 2016-07-12)One gracity core NP05–11–49GC was retrieved from a 320 m water depth in the central part of Erik Eriksen Strait, south of Nordaustlandet, northwestern Barents Sea. The core was investigated for benthic foraminiferal distribution patterns, stable isotopes and sedimentological parameters in order to reconstruct the Late Weichselian deglaciation and Holocene paleoenvironment and paleoceanography of the ... -
A methodology for identification of suitable drilling waste handling systems in the Arctic region
(Journal article; Peer reviewed; Tidsskriftartikkel, 2016)As the demands to reduce the environmental impact of oil and gas operations increase in the Arctic region, the need to identify suitable waste handling systems become more essential. The aim of this paper is to propose a methodology for identifying suitable drilling waste handling system, by considering the distinctive operating condition of the Arctic region. The proposed methodology can help the ... -
Utdanning for bærekraftig utvikling (UBU) fra et lærerperspektiv. En studie av naturfaglæreres perspektiv og undervisningspraksis av UBU
(Master thesis; Mastergradsoppgave, 2016-06-01)Hensikten med dette masterprosjektet har vært å utforske hvordan utdanning for bærekraftig utvikling (UBU) gjennomføres av naturfaglærere på Vg1-nivå i den videregående skolen, samt hvilke utfordringer lærerne knytter til å virkeliggjøre intensjonene om UBU. Internasjonale og nasjonale studier påpeker utdanningens rolle for å imøtekomme de samfunnsmessige omstillingene verden behøver for å oppnå en ... -
Utforskende uteundervisning i naturfag. Vil elevenes motivasjon for læring i naturfag øke som følge av utforskende uteundervisning i nærområdet?
(Master thesis; Mastergradsoppgave, 2016-06-01)Oppgaven har som hensikt å undersøke om elevenes motivasjon for læring i naturfag øker som følge av utforskende uteundervisning i nærområdet. Ved bruk av kvantitative metoder har motivasjonsnivå blitt kartlagt for tre 6. klasser ved to ulike skoler i Varanger. En skole vektlegger friluftsliv og uteskole i sin skoleprofil mens den andre skolen anvender uteundervisning mer sjeldent. For å undersøke ... -
Human teenagers defect more often when told to be pure altruistic
(Master thesis; Mastergradsoppgave, 2016-05-25)Humans (Homo sapiens) are known to cooperate with non-kin and even strangers, yet there is no absolute explanation to human cooperation nor to non-kin altruism. Specific human traits such as memory and reputation fuels systems of reciprocity, policing, reward and punishment which all contribute to cooperation in social interactions. How do people adopt their moral heuristics to knowledge of the most ... -
Iridium-PHOX-mediated alkene hydrogenation: Isomerisation influences the stereochemical outcome
(Journal article; Tidsskriftartikkel; Peer reviewed, 2014-05-27)Recent experimental studies of iridium-phosphinooxazoline-mediated alkene hydrogenation indicated two dihydride species as resting states, with the minor isomer assumed to give rise to the major product enantiomer [Gruber and Pfaltz, Angew. Chem. Int. Ed. 2014, 53, 1896]. B3LYP-D2 calculations confirm the two dihydride intermediates as resting states but show that these species do not give rise to ... -
Fatigue Awareness. Introducing fatigue awareness devices as a part of FRMS in an airline
(Master thesis; Mastergradsoppgave, 2016-06-01)Fatigue has become more of broad and current interest, and has been claimed to be a contributing factor in several aviation accidents and incidents (European Cockpit Association, 2010; Flin, 2008). The International Air Transport Association (ICAO) changed one of their annexes in 2012, allowing fatigue risk management systems (FRMS) instead of prescriptive flight time limitations. From 2018 there ... -
Er debriefing bortkastet tid? En studie av emosjonell ventilering og læring i et brannvesen.
(Master thesis; Mastergradsoppgave, 2016-06-01)Oppgaven er en casestudie av hvordan debriefing benyttes i et brannvesen. Oppgaven vil besvare hvordan dagens praksis for debriefing påvirker emosjonell ventilering og læring. Oppgavens bakteppe er en pågående akademisk debatt om hvorvidt debriefing bør benyttes. I denne oppgaven skiller jeg på psykologisk debriefing og taktisk debriefing. Litteraturen for begge disse formene for debriefing er ...
