Sökning: "counterion"

Visar resultat 21 - 25 av 33 avhandlingar innehållade ordet counterion.

1. 21. Swelling and Mechanical Properties of Polymer Gels: Salt, Macroion and Network Topology Effects

   Författare :Samuel Edgecombe; Fysikalisk kemi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; volume decrease upon uniaxial extension; interpenetrating networks; loose-end effects; polydispersity effects; macroion deswelling; salt deswelling; polymer gels; polyelectrolyte gels; Physical chemistry; Fysikalisk kemi;

   Sammanfattning : The work in this thesis concerns polymer gels, especially their swelling and mechanical properties modelled using a coarse-grained model of polyelectrolytes. The method used to study polymer gels was molecular simulation utilising the simulation package MOLSIM. LÄS MER

3. 22. Effects of polyelectrolyte conformation, charge density and ion specificity in polyelectrolyte and polyelectrolyte-drug interaction

   Författare :Andreas M. Hugerth; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutical chemistry; Farmaceutisk kemi; Pharmaceutical chemistry; Farmaceutisk kemi; Physical and Inorganic Pharmaceutical Chemistry; fysikalisk och oorganisk farmaceutisk kemi;

   Sammanfattning : The central theme is how the structural characteristics of sulphated polyelectrolytes and theirinteraction with counter- and coions determine the degree of polyelectrolyte self-association (gelformation), interaction with oppositely charged polyelectrolyte and polyelectrolyte-amphiphilic druginteraction in protolytic solvent medium. Such knowledge is essential for understanding and regulatingthe interaction between polyelectrolytes as well as between polyelectrolytes and a drug substance in apharmaceutical formulation and for its fate in the human organism. LÄS MER

4. 23. Characterisation of Aqueous Solutions, Liquid Crystals and Solid State of Non-ionic Polymers in Association with Amphiphiles and Drugs

   Författare :Annika Ridell; Martin Malmsten; Sven Engström; David Attwood; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; polymer; surfactant; phase diagram; x-ray diffraction; fluorescence spectroscopy; calorimetry; PEG; cellulose ether; viscometry; cubic phase; liquid crystals; drugs; solid dispersion; Fysikalisk kemi; Physical chemistry; Fysikalisk kemi; Fysikalisk och oorganisk farmaceutisk kemi; Physical and Inorganic Pharmaceutical Chemistry;

   Sammanfattning : Cellulose ethers and polyethylene glycols are used in drug formulations as water swelling or water soluble matrices. Polar lipids, for example monoglycerides, and surfactants can be used to solubilise hydrophobic or amphiphilic drugs and to formulate potential drug delivery vehicles such as emulsions, liposomes and cubic phases. LÄS MER

5. 24. Novel Gemini Surfactants Based on Natural Products Aggregation Behaviour in Aqueous Solutions

   Författare :El-Ouafi Alami; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cyclodextrin; micelles; NMR self-diffusion; heterogemini surfactant; adsorption; micellar model; small-angle neutron-scattering; surface tension;

   Sammanfattning : There is currently much interest in using natural products to obtain novel types of surfactants. One of the reasons for increasing the proportion of surfactants based on natural products and replacing products based on petroleum raw materials is the growing concern about the environment. LÄS MER

7. 25. On the exposure assessment of engineered nanoparticles in aquatic environments

   Författare :Julian A. Gallego-Urrea; Göteborgs universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; aquatic nanoparticles; exposure assessment;

   Sammanfattning : The socio-economic benefits anticipated with the use and production of nanomaterial and nanoparticles in consumer products are linked to the fulfillment of the requirement for sustainability during the whole material life cycle. Engineered nanoparticles (ENP) can be of environmental concern, both due to the possible hazardous effects but also due to the differences in properties compared to regular chemicals, e. LÄS MER