Blar i Institutt for ingeniørfag på forfatter "Kjøniksen, Anna-Lena"
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Effect of Calcium Expansive Additives on the Performance of Granite-Based Geopolymers for Zonal Isolation in Oil and Gas Wells
Gomado, Foster Dodzi; Khalifeh, Mahmoud; Saasen, Arild; Sanfelix, Susana G.; Kjøniksen, Anna-Lena; Aasen, Jan Aage (Peer reviewed; Journal article, 2023)Geopolymers have emerged as a promising alternative to Portland cement for oil and gas wells. Achieving effective zonal isolation by use of geopolymers may require controlling their expansion. This study investigates the ... -
Energy Lost in a Hydrogel Osmotic Engine Due to a Pressure Drop
Bui, Tri Quang; Cao, Vinh Duy; Wang, Wei; Nguyen, Thanh Hung; Kjøniksen, Anna-Lena (Peer reviewed; Journal article, 2021)Utilizing hydrogels to harvest salinity gradient energy from solutions of different salinities has recently attracted interest. Polyelectrolyte hydrogels exhibit cyclic swelling/deswelling when alternately exposed to ... -
Flame retardancy of rigid polyurethane foams containing thermoregulating microcapsules with phosphazene-based monomers
Madsen, Dan; Serrano, Angel; Carmona, Manuel; Van Hees, Patrick; Rodriguez, Juan F.; Kjøniksen, Anna-Lena (Peer reviewed; Journal article, 2021)Thermoregulating microcapsules (MC) with flame-retardant properties were used to produce polyurethane (PU) foams. Thermogravimetric analyses of the microcapsules performed under atmospheric air and nitrogen confirmed that ... -
Investigation of severe lunar environmental conditions on the physical and mechanical properties of lunar regolith geopolymers
Pilehvar, Shima; Arnhof, Marlies; Erichsen, Andreas; Valentini, Luca; Kjøniksen, Anna-Lena (Peer reviewed; Journal article, 2021)3D-printing of geopolymers produced from lunar regolith is an interesting option for space in situ habitats. In this study, the influence of the severe lunar environmental conditions such as extreme temperature variations ... -
New Water-Ethylene Glycol Lubricants with Stearate Ionic Liquid Crystal Additive
Avilés, María-Dolores; Sánchez-Rodríguez, Cristian; Pamies, Ramon; Bermúdez, María-Dolores; Carrión-Vilches, Francisco-José; Sanfèlix, Susana García; Kjøniksen, Anna-Lena (Peer reviewed; Journal article, 2022)The main purpose of the present study is to improve the tribological performance of aqueous lubricants with the use of ecofriendly, fatty acid-derived additives. The protic ionic liquid crystal bis(2-hydroxyethyl)ammonium ... -
Osmotic engine converting energy from salinity difference to a hydraulic accumulator by utilizing polyelectrolyte hydrogels
Bui, Tri Quang; Magnussen, Ole-Petter; Cao, Vinh Duy; Wang, Wei; Kjøniksen, Anna-Lena; Aaker, Olav (Peer reviewed; Journal article, 2021)Efficient harvesting of the mixing energy from the salinity gradient between sea and river water remains a challenge. Recently, utilization of the swelling/shrinking properties of hydrogels has been explored as a new means ... -
Recovered Energy from Salinity Gradients Utilizing Various Poly(Acrylic Acid)-Based Hydrogels
Bui, Tri Quang; Cao, Vinh Duy; Wang, Wei; Kjøniksen, Anna-Lena (Peer reviewed; Journal article, 2021)Hydrogels can be utilized to extract energy from salinity gradients when river water mixes with seawater. Saline-sensitive hydrogels exhibit a reversible swelling/shrinking process when they are, alternately, exposed to ... -
Synthesis and antimicrobial activities of chitosan/polypropylene carbonate-based nanoparticles
Quan, Zhilong; Luo, Chunyang; Zhu, Bitong; Zhao, Chungui; Yang, Mingyi; Bjørås, Magnar; Zhu, Kaizheng; Kjøniksen, Anna-Lena (Peer reviewed; Journal article, 2021)Antibiotic resistance is an emerging threat to public health. The development of a new generation of antimicrobial compounds is therefore currently required. Here we report a novel antimicrobial polymer of chitosan/polypropylene ...