Sökning: "sulfone"

Visar resultat 6 - 10 av 18 avhandlingar innehållade ordet sulfone.

1. 6. Surfactant Responsive Cross-Linked Polymer Hydrogels

   Författare :Jesper Sjöström; Research Policy Institute (RPI); []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Fysikalisk kemi; Two-step binding isotherms; Resolubilization; Nonmonotonic transient volume changes; Swelling isotherms; Divinyl sulfone DVS ; Polyquaternium; Cellulose ethers; Amphiphilic cross-linked polymers; Responsive gels; Polymer-surfactant interactions;

   Sammanfattning : The focus of the thesis is on chemically cross-linked hydrogels which drastically change their volume when immersed in solutions of different ionic surfactants (with or without added salt). The two main questions addressed are: (1) How useful are simple gel swelling experiments to the study of polymer-surfactant interactions?, and (2) How does the volume of a cross-linked polymer gel change when it is immersed in a surfactant solution, both with respect to the equilibrium swelling and with respect to transient volume changes? Most of the gels studied were prepared by cross-linking linear polymers, which were well studied derivatives of hydroxyethyl cellulose (HEC). LÄS MER

3. 7. Aromatic Polymers Functionalized with Anionic and Cationic Groups for Ion Exchange Membranes

   Författare :Annika Weiber; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Ion exchange membranes; fuel cells; polycondensation; local ion density; poly arylene ether sulfone s;

   Sammanfattning : Fuel cells, redox flow batteries and some water desalination technologies such as reverse osmosis and electrodialysis require efficient ion exchange membranes to perform in an optimum way. Thus, by enhancing the properties of these membranes there is a possibility to improve this type of applications and technologies. LÄS MER

4. 8. Durable Polysulfones with Densely Sulfonated Segments for Highly Proton Conducting Membranes

   Författare :Shogo Takamuku; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polymer electrolytes; sulfonations; polycondensation; polyaromatics; ionomers; sulfonated monomers; block copolymers; segmented copolymers; sequenced copolymers; poly arylene ether sulfone s; lithiations; sulfinations; metalations; phase-separation; highly sulfonations; macromonomers; blocky structures;

   Sammanfattning : Fuel cells are considered as a promising alternative environmentally benign power source to the existing ones depending on petroleum oil. Especially, proton-exchange membrane fuel cells (PEMFCs) have been intensively developed during the last decade because of their wide application windows including various portable, stationary and transportation applications. LÄS MER

5. 9. Copper-Mediated Vicarious Nucleophilic Substitution

   Författare :Olof Haglund; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES;

   Sammanfattning : This thesis suggests and examines a novel approach for copper-mediated cross-couplings. We call this mechanistic approach copper-mediated vicarious nucleophilic substitution. Our hypothesis is that copper-promoted cross-couplings proceed via an intermediate s-adduct, a Meisenheimer adduct. LÄS MER

7. 10. CHALMEX FS-13 investigations for process implementation

   Författare :Thea Lyseid Authen; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transmutation; SolventExtraction; CHALMEX; Partitioning; GANEX;

   Sammanfattning : From successive neutron absorption by uranium in nuclear reactors, transuranic elements such as neptunium, plutonium, americium and curium are produced. These elements are the main reason for the long-lived, highly radiotoxic and heat-producing nature of spent nuclear fuel. LÄS MER