Now showing items 1-10 of 2365
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 ...
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 ...
Integrated Monitoring of Mola mola Behaviour in Space and Time
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-05)
Over the last decade, ocean sunfish movements have been monitored worldwide using various satellite tracking methods. This study reports the near-real time monitoring of fine-scale (< 10 m) behaviour of sunfish. The study was conducted in southern Portugal in May 2014 and involved satellite tags and underwater and surface robotic vehicles to measure both the movements and the contextual environment ...
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 ...
Analytical and Case Studies of a Sandwich Structure using Euler-Bernoulli Beam Equation
(Journal article; Tidsskriftartikkel; Peer reviewed, 2016-11)
This paper presents analytical and case studies of sandwich structures. In this study, the Euler-Bernoulli beam equation is solved analytically for a four-point bending problem. Appropriate initial and boundary conditions are specified to enclose the problem. In addition, the balance coefficient is calculated and the Rule of Mixtures is applied. The focus of this study is to determine the effective ...
Applicability Extent of 2-D Heat Equation for Numerical Analysis of a Multiphysics Problem
(Journal article; Tidsskriftartikkel; Peer reviewed, 2017-01)
This work focuses on thermal problems, solvable using the heat equation. The fundamental question being answered here is: what are the limits of the dimensions that will allow a 3-D thermal problem to be accurately modelled using a 2-D Heat Equation? The presented work solves 2-D and 3-D heat equations using the Finite Difference Method, also known as the Forward-Time Central-Space (FTCS) method, ...
Iron/Brønsted Acid Catalyzed Asymmetric Hydrogenation: Mechanism and Selectivity-Determining Interactions
(Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-03)
Hydrogenation catalysts involving abundant base metals such as cobalt or iron are promising alternatives to precious metal systems. Despite rapid progress in this field, base metal catalysts do not yet achieve the activity and selectivity levels of their precious metal counterparts. Rational improvement of base metal complexes is facilitated by detailed knowledge about their mechanisms and ...
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.
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 ...
Middle to Late Devonian–Carboniferous collapse basins on the Finnmark Platform and in the southwesternmost Nordkapp basin, SW Barents Sea
(Journal article; Tidsskriftartikkel; Peer reviewed, 2018-03-28)
The SW Barents Sea margin experienced a pulse of extensional deformation in the Middle–Late Devonian through the Carboniferous, after the Caledonian Orogeny terminated. These events marked the initial stages of formation of major offshore basins such as the Hammerfest and Nordkapp basins. We mapped and analyzed three major fault complexes, (i) the Måsøy Fault Complex, (ii) the Rolvsøya fault, and ...