Viser treff 2797-2816 av 4753

    • N-(3-hydroxyphenyl)acetamide 

      Hansen, Lars Kr; Perlovich, German; Bauer-Brandl, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2006)
    • N-Heteroaryl Carbamates from Carbon Dioxide via Chemoselective Superbase−Catalysis: Substrate Scope and Mechanistic Investigation 

      Mannisto, Jere K.; Pavlovic, Ljiljana; Heikkinen, Johannes; Tiainen, Tony; Sahari, Aleksi; Maier, Norbert; Rissanen, Kari; Nieger, Martin; Hopmann, Kathrin Helen; Repo, Timo (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-08-16)
      We report a mild superbase-catalyzed and nitrogen-selective carboxylation of N-heteroaryls, with subsequent alkylation enabling the synthesis of drug-like O-alkyl carbamates in good yields (av. 86%). Our findings suggest a partial revision of the current mechanistic understanding as superbases upon mixing with indoles and azoles generally form uncharged hydrogen-bonded complexes and not ionic salts ...
    • Na lidar measurements during the ECOMA/Geminids campaign with focus on Na peak density and temperature 

      Østerpart, Jørgen Olai Kristensen (Master thesis; Mastergradsoppgave, 2011-02)
      Using a resonance lidar, atomic Na (sodium) can be observed in the 80-110 km altitude range of the atmosphere. Na belongs to the alkali metal group and is highly reactive, so one could expect that it would quickly react with other particles and leave its atomic state. Its actual behaviour however includes the formation of relatively dense layers which, from the perspective of a stationary lidar, ...
    • Nanoscopy of bacterial cells immobilized by holographic optical tweezers 

      Diekmann, Robin; Wolfson, Deanna; Spahn, Christoph; Heilemann, Mike; Schuttpelz, Mark; Huser, Thomas (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-12-13)
      Imaging non-adherent cells by super-resolution far-field fluorescence microscopy is currently not possible because of their rapid movement while in suspension. Holographic optical tweezers (HOTs) enable the ability to freely control the number and position of optical traps, thus facilitating the unrestricted manipulation of cells in a volume around the focal plane. Here we show that immobilizing ...
    • Natural and anthropogenic deposition in Bøkfjorden 

      Ladstein, Anette Klev (Master thesis; Mastergradsoppgave, 2018-05-15)
      The aim for this study is to characterise and distinguish natural and anthropogenic deposition in Bøkfjorden, and to identify the spreading and the impact of submarine tailings placements on the seafloor. The analyses are based on the integration of swath bathymetry, high-resolution seismics and multi-proxy analyses of four sediment cores The physical properties, including magnetic susceptibility ...
    • Natural occuring oil seepages as a consequence of bottom trawling? 

      Hindenes, Sander (Mastergradsoppgave; Master thesis, 2023-05-31)
      Bottom trawling is used to capture fish species that live in the seabed. The damage on the seabed trawling causes has been discussed for many years. This thesis aims to investigate whether bottom trawling for sand eels can be a cause for some of the detected oil seepages in the North Sea. We investigated this using manual delineation of oil seepages in Synthetic Aperture Radar (SAR) satellite ...
    • Natural variability of benthic foraminiferal assemblages and metal concentrations during the last 150 years in the Ingøydjupet trough, SW Barents Sea. 

      Dijkstra, Noortje; Junttila, Juho; Husum, Katrine; Carroll, JoLynn; Hald, Morten (Journal article; Tidsskriftartikkel, 2015-12)
      While today the SW Barents Sea is a relatively un-impacted and uncontaminated area, industrial activities related to the petroleum industry are projected to increase in the coming decades. This makes the area a valuable natural laboratory to establish pre-impacted baselines as a precursor for future seabed monitoring programs. Here we present benthic foraminiferal assemblages and metal concentrations ...
    • Nature of the copper-nitrosyl intermediates of copper nitrite reductases during catalysis 

      Ghosh, Abhik; Conradie, Jeanet; Strange, Richard W; Antonyuk, Svetlana V; Eady, Robert R; Hasnain, Samar (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-20)
      The design and synthesis of copper complexes that can reduce nitrite to NO has attracted considerable interest. They have been guided by the structural information on the catalytic Cu centre of the widespread enzymes Cu nitrite reductases but the chemically novel side-on binding of NO observed in all crystallographic studies of these enzymes has been questioned in terms of its functional relevance. ...
    • Nature of the copper-nitrosyl intermediates of copper nitrite reductases during catalysis 

      Hough, Michael A.; Conradie, Jeanet; Strange, Richard W.; Antonyuk, Svetlana V.; Eady, Robert R.; Ghosh, Abhik; Hasnain, S. Samar (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-10-20)
      The design and synthesis of copper complexes that can reduce nitrite to NO has attracted considerable interest. They have been guided by the structural information on the catalytic Cu centre of the widespread enzymes Cu nitrite reductases but the chemically novel side-on binding of NO observed in all crystallographic studies of these enzymes has been questioned in terms of its functional relevance. ...
    • The nature of the gas-hydrate/free gas transition zone at the base of the hydrate-stability zone from high-resolution 3D seismic data 

      Bjørnøy, Kirsti (Master thesis; Mastergradsoppgave, 2015-01-26)
      Geophysical evidence of a prominent BSR at Vestnesa Ridge and north to the northern flank of the Storegga slide escarpment infer that gas hydrates are ubiquitous within these regions. A wide range of fluid flow structures have previously been discovered from these regions, as well as gas seepage activity from pockmarks on the eastern segment of Vestnesa Ridge. This paper focuses on high-resolution ...
    • Nature reserves as a bioeconomic management tool. A simplified modeling approach 

      Flåten, Ola; Mjølhus, Einar (Working paper; Arbeidsnotat, 2006-02)
      This paper demonstrates analytically how a nature reserve may protect the total population, realize maximum sustainable yield (MSY), maximum economic yield (MEY) and consumer surplus (CS) and how this depends on biological growth, migration, reserve size and economic parameters. The pre-reserve population is assumed to follow the logistic growth law and two post-reserve growth models are discussed. ...
    • Naturvitenskapens grunnlag og begrensning. Seminarrapport 

      Thorvaldsen, Steinar (Research report; Forskningsrapport, 1979)
      Foredrag av Arthur E. Wilder-Smith og Udo Middelmann holdt ved NTH i 1979
    • Navigation in the Arctic. How can simulator training be used for assessment and reduction of risk? 

      Røds, Johan-Fredrik (Master thesis; Mastergradsoppgave, 2018-06-01)
      Over the recent years, the ship traffic in the polar areas has increased. There is reason to believe that this traffic, and especially the cruise traffic, will increase further as the ice retracts towards the poles. There is also reason to believe that with the continued focus and exposure of the Polar Region, the cruise tourism to the region will grow.The increased presence in the polar areas will ...
    • Når tiden er knapp, forholdene er tøffe, men det står liv på spill: En spørreskjemaundersøkelse om emosjonell påvirkning, beslutningstaking og CRM hos luftambulanseflygere 

      Granli, Marius Møllevik (Master thesis; Mastergradsoppgave, 2023-05-31)
      Luftambulansetjenesten HF har i dag kontrakt med Avincis Aviation Services, som opererer luftambulanseflyene i Norge. Denne delen av tjenesten hadde 109.095 oppdrag i tiårsperioden 2013-2022, hvorav 30.0% var haste- eller akuttoppdrag. Luftambulansetjenesten har blitt beskrevet av flere som en samfunnskritisk ressurs, da befolkningen i Norge har rett på lik medisinsk behandling uavhengig av ...
    • NB-FEB : an easy-to-use and scalable universal synchronization primitive for parallel programming 

      Ha, Hoai Phuong; Tsigas, Philippas; Anshus, Otto J. (Research report; Forskningsrapport, 2008-10)
      This paper addresses the problem of universal synchronization primitives that can support scalable thread synchronization for large-scale many-core architectures. The universal synchronization primitives that have been deployed widely in conventional architectures, are the compare-and-swap (CAS) and load-linked/store-conditional (LL/SC) primitives. However, such synchronization primitives are ...
    • Necessary Conditions for Warm Inflow Toward the Filchner Ice Shelf, Weddell Sea 

      Daae, Kjersti; Hattermann, Tore; Darelius, Elin Maria K.; Mueller, Rachael D.; Naughten, Kaitlin A; Timmermann, Ralph; Hellmer, Hartmut H. (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-11-09)
      Understanding changes in Antarctic ice shelf basal melting is a major challenge for predicting future sea level. Currently, warm Circumpolar Deep Water surrounding Antarctica has limited access to the Weddell Sea continental shelf; consequently, melt rates at Filchner‐Ronne Ice Shelf are low. However, large‐scale model projections suggest that changes to the Antarctic Slope Front and the coastal ...
    • Negational symmetry of quantum neural networks for binary pattern classification 

      Dong, Nanqing; Kampffmeyer, Michael; Voiculescu, Irina; Xing, Eric (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-04-27)
      Although quantum neural networks (QNNs) have shown promising results in solving simple machine learning tasks recently, the behavior of QNNs in binary pattern classification is still underexplored. In this work, we find that QNNs have an Achilles’ heel in binary pattern classification. To illustrate this point, we provide a theoretical insight into the properties of QNNs by presenting and analyzing ...
    • Neo: Virtual Object Modeling using Commodity Hardware 

      Bye Nilsen, Thomas (Master thesis; Mastergradsoppgave, 2019-05-15)
      Recent developments in augmented reality technology have paved way for newapplications in a wide range of areas. These include the commercial markets,medicine applications, military applications and education. The technology pro-vides immersive images to enhance our perception of the world. Augmentedreality addresses challenges related to problem-solving by seamlessly integrat-ing digital images ...
    • Neodymium isotope constraints on chemical weathering and past glacial activity in Svalbard 

      Jang, Kwangchul; Bayon, Germain; Han, Yeongcheol; Joo, Young Ji; Kim, Ji-Hoon; Ryu, Jong-Sik; Woo, Jusun; Forwick, Matthias; Szczuciński, Witold; Kim, Jung-Hyun; Nam, Seung-Il (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-05-15)
      <p>Neodymium (Nd) isotopes in leached authigenic components of marine sediments have been increasingly used as a tracer of past ocean-water masses. Despite the general assumption that the Nd isotopic composition of solutes released during chemical weathering fingerprints the source rocks on continents, preferential dissolution of easily dissolvable phases may result in significant deviations in Nd ...
    • Neogene dinoflagellate cysts and acritarchs from the high northern latitudes and their relation to sea surface temperature 

      Schreck, Michael; Nam, Seung-Il; Clotten, Caroline; Fahl, Kirsten; De Schepper, Stijn; Forwick, Matthias; Matthiessen, Jens (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-09-13)
      <p>Organic-walled dinoflagellate cysts and acritarchs are a vital tool for reconstructing past environmental change, in particular in the Neogene of the high northern latitudes where marine deposits are virtually barren of traditionally used calcareous microfossils. Yet only little is known about the paleoenvironmental value of fossil assemblages that do not have modern analogues, so that reconstructions ...