• Application of nanoparticles for oil recovery. 

      Torsæter, Ole (Peer reviewed; Journal article, 2021)
      Due to their large surface-area-to-volume ratio and enhanced chemical reactivity, nanoparticles have attracted interest among researchers in the upstream petroleum industry for oil recovery applications. Nanoparticles have ...
    • A core flood and microfluidics investigation of nanocellulose as a chemical additive to water flooding for EOR 

      Aadland, Reidun Cecilie Grønfur; Akarri, Salem Saeed Fadhl; Heggset, Ellinor Bævre; Syverud, Kristin; Torsæter, Ole (Peer reviewed; Journal article, 2020)
      Cellulose nanocrystals (CNCs) and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofibrils (T-CNFs) were tested as enhanced oil recovery (EOR) agents through core floods and microfluidic experiments. ...
    • Enhancement of Thermal Boundary Conductance of Metal–Polymer System 

      Sandell, Susanne; Maire, Jeremie; Chavez-Angel, Emigdio; Sotomayor Torres, Clivia M.; Kristiansen, Helge; Zhang, Zhiliang; He, Jianying (Peer reviewed; Journal article, 2020)
      In organic electronics, thermal management is a challenge, as most organic materials conduct heat poorly. As these devices become smaller, thermal transport is increasingly limited by organic–inorganic interfaces, for ...
    • Experimental Investigation of Polymer-Coated Silica Nanoparticles for Enhanced Oil Recovery. 

      Bila, Alberto Luis; Stensen, Jan Åge; Torsæter, Ole (Journal article; Peer reviewed, 2019)
      Recently, polymer-coated nanoparticles were proposed for enhanced oil recovery (EOR) due to their improved properties such as solubility, stability, stabilization of emulsions and low particle retention on the rock surface. ...
    • Experimental investigation of polymer-coated silica nanoparticles for EOR under harsh reservoir conditions of high temperature and salinity. 

      Bila, Alberto Luis; Torsæter, Ole (Peer reviewed; Journal article, 2021)
      Laboratory experiments have shown higher oil recovery with nanoparticle (NPs) flooding. Accordingly, many studies have investigated the nanoparticle-aided sweep efficiency of the injection fluid. The change in wettability ...
    • Exposure to ultrafine particles in the ferroalloy industry using a logbook method 

      Jørgensen, Rikke Bramming; Kero, Ida; Blom, Aleksander; Grove, Esten Eide; Svendsen, Kristin V Hirsch (Peer reviewed; Journal article, 2020)
      Background: It is difficult to assess workers’ exposure to ultrafine particles (UFP) due to the lack of personal sampling equipment available for this particle fraction. The logbook method has been proposed as a general ...
    • Graphene H-Waveguide for Terahertz Lasing Applications: Electromagnetic Quasi-Linear Theory 

      Kouzaev, Guennadi (Peer reviewed; Journal article, 2020)
      A novel graphene H-waveguide is proposed for active terahertz components. A graphene film illuminated by strong pumping light shorts the parallel conductor plates. The terahertz modes propagating along this film are amplified ...
    • High salinity and high temperature stable colloidal silica nanoparticles with wettability alteration ability for EOR application. 

      Hadia, Nanji; Ng, Yeap Hung; Stubbs, Ludger P.; Torsæter, Ole (Peer reviewed; Journal article, 2021)
      The stability of nanoparticles at reservoir conditions is a key for a successful application of nanofluids for any oilfield operations, e.g., enhanced oil recovery (EOR). It has, however, remained a challenge to stabilize ...
    • High-Temperature Core Flood Investigation of Nanocellulose as a Green Additive for Enhanced Oil Recovery 

      Aadland, Reidun Cecilie Grønfur; Jakobsen, Trygve Dagsloth; Heggset, Ellinor Bævre; Long-Sanouiller, Haili; Simon, Sebastien Charles; Paso, Kristofer Gunnar; Syverud, Kristin; Torsæter, Ole (Journal article; Peer reviewed, 2019)
      Recent studies have discovered a substantial viscosity increase of aqueous cellulose nanocrystal (CNC) dispersions upon heat aging at temperatures above 90 °C. This distinct change in material properties at very low ...
    • Identification of Nanocellulose Retention Characteristics in Porous Media 

      Aadland, Reidun Cecilie Grønfur; Dziuba, Carter Jordan; Heggset, Ellinor Bævre; Syverud, Kristin; Torsæter, Ole; Holt, Torleif; Gates, Ian D.; Bryant, Steven (Journal article; Peer reviewed, 2018)
      The application of nanotechnology to the petroleum industry has sparked recent interest in increasing oil recovery, while reducing environmental impact. Nanocellulose is an emerging nanoparticle that is derived from trees ...
    • Introducing Well-Defined Nanowrinkles in CVD Grown Graphene 

      Verhagen, Tim; Pacáková, Barbara; Kalbac, Martin; Vejpravova, Jana (Journal article; Peer reviewed, 2019)
      The control of graphene’s topography at the nanoscale level opens up the possibility to greatly improve the surface functionalization, change the doping level or create nanoscale reservoirs. However, the ability to control ...
    • Kirkwood–Buff Integrals Using Molecular Simulation: Estimation of Surface Effects 

      Dawass, Noura; Krüger, Peter; Schnell, Sondre Kvalvåg; Moultos, Othonas A.; Economou, Ioannis; Vlugt, Thijs J.H.; Simon, Jean-Marc (Peer reviewed; Journal article, 2020)
      Kirkwood–Buff (KB) integrals provide a connection between microscopic properties and thermodynamic properties of multicomponent fluids. The estimation of KB integrals using molecular simulations of finite systems requires ...
    • A Legendre–Fenchel Transform for Molecular Stretching Energies 

      Bering, Eivind; Bedeaux, Dick; Kjelstrup, Signe; de Wijn, Astrid S.; Latella, Ivan; Rubi, Miguel (Peer reviewed; Journal article, 2020)
      Single-molecular polymers can be used to analyze to what extent thermodynamics applies when the size of the system is drastically reduced. We have recently verified using molecular-dynamics simulations that isometric and ...
    • Nanofiber NiMoO4/g-C3N4 Composite Electrode Materials for Redox Supercapacitor Applications 

      Thiagarajan, Kannadasan; Bavani, Thirugnanam; Arunachalam, Prabhakarn; Lee, Seung Jun; Theerthagiri, Jayaraman; Madhavan, Jaganathan; Pollet, Bruno; Choi, Myong Yong (Journal article; Peer reviewed, 2020)
      NiMoO4/g-C3N4 was fabricated by a hydrothermal method and used as an electrode material in a supercapacitor. The samples were characterized by XRD, FTIR, scanning electron microscopy (SEM) and transmission electron microscopy ...
    • Nanothermodynamic Description and Molecular Simulation of a Single-Phase Fluid in a Slit Pore 

      Galteland, Olav; Bedeaux, Dick; Kjelstrup, Signe (Peer reviewed; Journal article, 2021)
      We have described for the first time the thermodynamic state of a highly confined single-phase and single-component fluid in a slit pore using Hill’s thermodynamics of small systems. Hill’s theory has been named ...
    • Oil-in-Water Emulsions Stabilized by Cellulose Nanofibrils—The Effects of Ionic Strength and pH 

      Aaen, Ragnhild; Brodin, Fredrik Wernersson; Simon, Sebastien Charles; Heggset, Ellinor Bævre; Syverud, Kristin (Journal article; Peer reviewed, 2019)
      Pickering o/w emulsions prepared with 40 wt % rapeseed oil were stabilized with the use of low charged enzymatically treated cellulose nanofibrils (CNFs) and highly charged 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized ...
    • Statistical Mechanics at Strong Coupling: A Bridge between Landsberg's Energy Levels and Hill's Nanothermodynamics 

      de Miguel, Rodrigo; Rubi, J. Miguel (Peer reviewed; Journal article, 2020)
      We review and show the connection between three different theories proposed for the thermodynamic treatment of systems not obeying the additivity ansatz of classical thermodynamics. In the 1950s, Landsberg proposed that ...
    • Structure and Optical Properties of Titania-PDMS Hybrid Nanocomposites Prepared by In Situ Non-Aqueous Synthesis 

      Dalod, Antoine Robert Marie; Grendal, Ola Gjønnes; Blichfeld, Anders Bank; Furtula, Vedran; Pérez, Javier; Henriksen, Lars; Grande, Tor; Einarsrud, Mari-Ann (Journal article; Peer reviewed, 2017)
      Organic-inorganic hybrid materials are attractive due to the combination of properties from the two distinct types of materials. In this work, transparent titania-polydimethylsiloxane hybrid materials with up to 15.5 vol. ...
    • Two-Phase Equilibrium Conditions in Nanopores 

      Rauter, Michael Tobias; Galteland, Olav; Erdos, Mate; Moultos, Othonas A.; Vlugt, Thijs J.H.; Schnell, Sondre Kvalvåg; Bedeaux, Dick; Kjelstrup, Signe (Peer reviewed; Journal article, 2020)
      It is known that thermodynamic properties of a system change upon confinement. To know how, is important for modelling of porous media. We propose to use Hill’s systematic thermodynamic analysis of confined systems to ...
    • When Thermodynamic Properties of Adsorbed Films Depend on Size: Fundamental Theory and Case Study 

      Strøm, Bjørn André; He, Jianying; Bedeaux, Dick; Kjelstrup, Signe (Peer reviewed; Journal article, 2020)
      Small system properties are known to depend on geometric variables in ways that are insignificant for macroscopic systems. Small system considerations are therefore usually added to the conventional description as needed. ...