Viser treff 1-20 av 557

    • 2-Pyridinyl/quinolyl-phenylamino-quinoline Complexes With CF3 and C2F5 Ligated Ni 

      Håheim, Katja Stangeland; Deolka, Shubham; Fayzullin, Robert; Lund, Bjarte Aarmo; Khaskin, Eugene; Sydnes, Magne Olav (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-21)
      A new ligand architecture based on quinoline/pyridine attached ortho to the amine functionality on an aniline, which is coupled to another quinoline unit has been prepared. Ligands <b>L1</b> and <b>L2</b> have been complexed with CF<sub>3</sub> and C<sub>2</sub>F<sub>5</sub> ligated nickel centers. The resulting complexes have been extensively studied by NMR spectroscopy (on <sup>1</sup>H, ...
    • Multiresolution of the one dimensional free-particle propagator. Part 1: Construction 

      Dinvay, Evgueni; Zabelina, Yuliya; Frediani, Luca (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-19)
      The free-particle propagator, a key operator in various algorithms for simulating the time evolution of the Schrödinger equation, is studied. A multiscale approximation of this propagator is constructed, representing the semigroup associated with the free-particle Schrödinger operator in a multiwavelet basis. This representation involves integrals of highly oscillatory functions. These integrals are ...
    • Multiresolution of the one dimensional free-particle propagator. Part 1: Construction 

      Zabelina, Yuliya; Frediani, Luca (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-19)
      The free-particle propagator, a key operator in various algorithms for simulating the time evolution of the Schrödinger equation, is studied. A multiscale approximation of this propagator is constructed, representing the semigroup associated with the free-particle Schrödinger operator in a multiwavelet basis. This representation involves integrals of highly oscillatory functions. These integrals are ...
    • Weekly Cumulative Quizzes in Organic Chemistry 

      Beerepoot, Maarten; Kosonen, Juho Aleksi; Haugland-Grange, Marius (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-11)
      A challenge in organic chemistry as well as in other subjects is that a set of fundamental skills is required to master more advanced topics. In an attempt to force students to invest in learning fundamental concepts before working with more advanced topics, we have introduced weekly compulsory quizzes and associated practice tests in our introductory organic chemistry course. The weekly quizzes are ...
    • Directional Multiobjective Optimization of Metal Complexes at the Billion-Scale with the tmQMg-L Dataset and PL-MOGA Algorithm 

      Kneiding, Hannes; Nova Flores, Ainara; Balcells Badia, David (Journal article; Tidsskriftartikkel, 2023-09-25)
      Transition metal complexes (TMCs) play a key role in several areas of high interest, including medicinal chemistry, renewable energies, and nanoporous materials. The development of TMCs enabling these technologies remains challenged by the need to optimize multiple properties within very large chemical spaces, in which the thirty transition metals can be combined with a virtually infinite number of ...
    • Automatisk rettet eksamen i generell kjemi 

      Beerepoot, Maarten; Kosonen, Juho Aleksi (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-29)
      En god avsluttende eksamen vurderer i hvilken grad intendert læringsutbytte har blitt oppnådd på en objektiv, reproduserbar og helst autentisk måte. Det er imidlertid lite tilfredsstillende hvis en faglærer bruker mye tid på vurdering av læring framfor vurdering for læring underveis i semesteret. Derfor kan det være attraktivt å utforske muligheter med en digital automatisk rettet eksamen, spesielt ...
    • Hyperspectral imaging and deep learning for parasite detection in white fish under industrial conditions 

      Syed, Shaheen; Ortega, Samuel; Anderssen, Kathryn Elizabeth; Nilsen, Heidi; Heia, Karsten (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-11-09)
      Parasites in fish muscle present a significant problem for the seafood industry in terms of both quality and health and safety, but the low contrast between parasites and fish tissue makes them exceedingly difficult to detect. The traditional method to identify nematodes requires removing fillets from the production line for manual inspection on candling tables. This technique is slow, labor intensive ...
    • Removal of per- and polyfluoroalkyl substances (PFAS) from water using magnetic cetyltrimethylammonium bromide (CTAB)-modified pine bark 

      Zhang, Ruichi; Ren, Zhongfei; Bergmann, Ulrich; Uwayezu, Jean Noel; Carabante, Ivan; Kumpiene, Jurate; Lejon, Tore Sigvard; Levakov, Ilil; Rytwo, Giora; Leiviskä, Tiina (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-09-02)
      Per- and polyfluoroalkyl substances (PFAS) have gained global attention in recent years due to their adverse effect on environment and human health. In this study, a novel and cost-effective sorbent was developed utilizing forestry by-product pine bark and tested for the removal of PFAS compounds from both synthetic solutions and contaminated groundwater. The synthesis of the adsorbent included two ...
    • A conservative stochastic Dirac-Klein-Gordon system 

      Dinvay, Evgueni; Selberg, Sigmund (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-07-04)
      Considered herein is a particular nonlinear dispersive stochastic system consisting of Dirac and Klein-Gordon equations. They are coupled by nonlinear terms due to the Yukawa interaction. We consider a case of homogeneous multiplicative noise that seems to be very natural from the perspective of the least action formalism. We are able to show existence and uniqueness of a corresponding Cauchy problem ...
    • Fitting to magnetic forces improves the reliability of magnetic Moment Tensor Potentials 

      Kotykhov, Alexey S.; Gubaev, Konstantin; Sotskov, Vadim; Tantardini, Christian; Hodapp, Max; Shapeev, Alexander V.; Novikov, Ivan S. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-29)
      We developed a method for fitting machine-learning interatomic potentials with magnetic degrees of freedom, namely, magnetic Moment Tensor Potentials (mMTP). The main feature of our method consists in fitting mMTP to magnetic forces (negative derivatives of energies with respect to magnetic moments) as obtained spin-polarized density functional theory calculations. We test our method on the bcc Fe–Al ...
    • Nickel Catalyzed Carbonylative Cross Coupling for Direct Access to Isotopically Labeled Alkyl Aryl Ketones 

      Mühlfenzl, Kim; Enemærke, Vitus; Gahlawat, Sahil; Golbækdal, Peter; Munksgaard-Ottosen, Nikoline; Neumann, Karoline; Hopmann, Kathrin Helen; Norrby, Per-Ola; Elmore, Charles; Skrydstrup, Troels (Journal article; Tidsskriftartikkel, 2024-08-15)
      Here we present an effective nickel-catalyzed carbonylative cross-coupling for direct access to alkyl aryl ketones from readily accessible redox-activated tetrachlorophthalimide esters and aryl boronic acids. The methodology, which is run employing only 2.5 equivalents of CO and simple Ni(II) salts as the metal source, exhibits a broad substrate scope under mild conditions. Furthermore, this ...
    • Computational Study of the Ir-Catalyzed Formation of Allyl Carbamates from CO2 

      Gahlawat, Sahil; Artselsmair, Markus; Castro, Abril C; Norrby, Per-Ola; Hopmann, Kathrin Helen (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-08-05)
      We have employed computational methods to investigate the iridium-catalyzed allylic substitution leading to the formation of enantioenriched allyl carbamates from carbon dioxide (CO<sub>2</sub>). The reaction occurs in several steps, with initial formation of an iridium-allyl, followed by nucleophilic attack by the carbamate formed in situ from CO<sub>2</sub> and an amine. A detailed isomeric analysis ...
    • Revisiting the mechanism of asymmetric Ni-catalyzed reductive carbo-carboxylation with CO2: The additives affect the product selectivity 

      Pavlovic, Ljiljana; Carvalho de Oliveira Gomes, Bjørn; Hopmann, Kathrin Helen (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-25)
      The mechanistic details of the asymmetric Ni-catalyzed reductive cyclization/carboxylation of alkenes with CO2 have been revisited using DFT methods. Emphasis was put on the enantioselectivity and the mechanistic role of Lewis acid additives and in situ formed salts. Our results show that oxidative addition of the substrate is rate-limiting, with the formed Ni(II)-aryl intermediate preferring a ...
    • Preparation of a high-coordinated-silicon-centered spiro-cyclic compound 

      Kushvaha, Saroj Kumar; Gorantla, Sai Manoj N. V. T.; Kallenbach, Paula; Herbst-Irmer, Regine; Stalke, Dietmar; Roesky, Herbert W. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-06-10)
      Silicon compounds containing silicon–silicon bond with a variety of unusual oxidation states are quite important, because their high reactivity leads to the formation of a variety of silicon compounds. The isolation of such compounds with unusual oxidation states requires a resilient synthetic strategy. Herein, we report the synthesis of a silicon based spirocyclic compound containing a hyper-valent ...
    • SARS-CoV2 Nsp1 is a metal-dependent DNA and RNA endonuclease 

      Salgueiro, Bruno A.; Saramago, Margarida; Tully, Mark D.; Issoglio, Federico; Silva, Sara T. N.; Paiva, Ana C. F.; Arraiano, Cecília M.; Matias, Pedro M.; Matos, Rute G.; Moe, Elin; Romão, Célia V. (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-03-28)
      Over recent years, we have been living under a pandemic, caused by the rapid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV2). One of the major virulence factors of Coronaviruses is the Non-structural protein 1 (Nsp1), known to suppress the host cells protein translation machinery, allowing the virus to produce its own proteins, propagate and invade new cells. To ...
    • Generating and grading 34 optimised norm-conserving Vanderbilt pseudopotentials for actinides and super-heavy elements in the PseudoDojo 

      Tantardini, Christian; Iliaš, Miroslav; Giantomassi, Matteo; Kvashnin, Alexander G.; Pershina, Valeria; Gonze, Xavier (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-11-07)
      In the last decades, material discovery has been a very active research field driven by the need to find new materials for many different applications. This has also included materials with heavy elements, beyond the stable isotopes of lead, as most actinides exhibit unique properties that make them useful in various applications. Furthermore, new heavy elements beyond actinides, collectively referred ...
    • Tinned: A symbolic library for response theory and high-order derivatives 

      Gao, Bin (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-23)
      A symbolic C++ library—Tinned—has been developed for symbolic differentiation and manipulation in response theory. By recognizing different key building blocks in the density matrix-based (Thorvaldsen et al., J. Chem. Phys. 2008, 129, 214108) and coupled-cluster response theories, we have implemented their corresponding C++ symbolic classes, including but not limited to one- and two-electron ...
    • Combination of separation and degradation methods after PFAS soil washing 

      Uwayezu, Jean Noel; Ren, Zhongfei; Sonnenschein, Sarah; Leiviskä, Tiina; Lejon, Tore; van Hees, Patrick; Karlsson, Patrik; Kumpiene, Jurate; Carabante, Ivan (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-10-26)
      The current study evaluated a three-stage treatment to remediate PFAS-contaminated soil. The treatment consisted of soil washing, foam fractionation (FF), and electrochemical oxidation (EO). The possibility of replacing the third stage, i.e., EO, with an adsorption process was also assessed. The contamination in the studied soils was dominated by perfluorooctane sulfonate (PFOS), with a concentration ...
    • Inverse Hypercorroles 

      Osterloh, W. Ryan; Desbois, Nicolas; Conradie, Jeanet; Gros, Claude P.; Kadish, Karl M.; Ghosh, Abhik (Journal article; Tidsskriftartikkel, 2024-05-02)
      Ground-state and time-dependent density functional theory (TDDFT) calculations with the long-range-corrected, Coulomb-attenuating CAMY-B3LYP exchange-correlation functional and large, all-electron STO-TZ2P basis sets have been used to examine the potential “inverse hypercorrole” character of meso-p-nitrophenyl-appended dicyanidocobalt(III) corrole dianions. The effect is most dramatic for ...
    • Electronic Structure of Metallophlorins: Lessons from Iridium and Gold Phlorin Derivatives 

      Larsen, Simon; Adewuyi, Joseph A.; Kolle Ekaney, Thomas; Conradie, Jeanet; Rousselin, Yoann; Ung, Gaël; Ghosh, Abhik (Journal article; Tidsskriftartikkel; Peer reviewed, 2024-05-14)
      Phlorins have long remained underexplored relative to their fully conjugated counterparts, such as porphyrins, hydroporphyrins, and corroles. Herein, we have attempted to bridge that knowledge gap with a scalar-relativistic density functional theory (DFT) study of unsubstituted iridium and gold phlorin derivatives and a multitechnique experimental study of iridium-bispyridine and gold complexes of ...