Sökning: "phosphate chemistry"

Visar resultat 21 - 25 av 150 avhandlingar innehållade orden phosphate chemistry.

1. 21. Bioaccessibility, corrosion and surface properties of metals, alloys and metallic powder in biological fluids of relevance for occupational and consumer health hazard assessment

   Författare :Xuying Wang; Inger Odnevall Wallinder; Yolanda S. Hedberg; Lars Nyborg; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Metal and alloy; metal release; synthetic biological fluids; surface oxide; corrosion resistance; hazard assessment; Kemi; Chemistry;

   Sammanfattning : When assessing hazards of metals, alloys, and metal-containing items, the metal release (bioaccessibility) is of high importance. Triggered by increasingly stricter hazard classifications for metals, especially cobalt (Co), and limited knowledge, the aim of this doctoral thesis is to assess correlations between the metal/alloy surface characteristics, corrosion and metal release pattern in different simulated biological fluids relevant to human exposure scenarios (dermal, ingestion and inhalation, Papers I-V). LÄS MER

3. 22. Stereoelectronic effects in nucleosides and nucleotides

   Författare :Christophe Thibaudeau; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Bioorganic chemistry; Bioorganisk kemi; Bioorganic chemistry; Bioorganisk kemi; bioorganisk kemi; Biorganic Chemistry;

   Sammanfattning : This thesis is based on 12 original publications from 1994-98. Intramolecular stereoelectronicforces (anomeric and gauche effects), beside intermolecular forces such as hydrogen bonding,base stacking, electrostatics and hydration, have been found to be responsible for the localstructural changes of DNA and RNA and their components. LÄS MER

4. 23. Charged Polymers: From DNA to Polyampholytes

   Författare :Malek O Khan; Beräkningskemi; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; computational steering; DNA condensation; ion correlations; electrostatic interactions; colloidal stability; polyampholytes; Monte Carlo simulations; polyelectrolytes; Theoretical chemistry; quantum chemistry; Teoretisk kemi; kvantkemi;

   Sammanfattning : Three main themes are outlined in this thesis: Polyelectrolytes/DNA : In a living cell, DNA molecules have a compact conformation in order to fit in, while in a test tube they will take on an expanded cylindrical shape, due to the negative phosphate groups along the DNA molecule. With the help of computer simulations it has been shown that like-charged monomers of a poly- electrolyte can attract each other if the counterions are taken into account. LÄS MER

5. 24. Structural Investigations of Complex Glasses by Solid-state NMR

   Författare :Ekaterina Leonova; Mattias Edén; Robin Harris; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; glass; glass structure and properties; NMR; magic angle spinning; chemical shift; Physical chemistry; Fysikalisk kemi; Physical Chemistry; fysikalisk kemi;

   Sammanfattning : This PhD thesis presents structural investigations of amorphous inorganic materials: oxide and oxynitride glasses and mesoporous bioactive glasses (MBGs), by solid-state Nuclear Magnetic Resonance (NMR). Lanthanum oxide and oxynitride [La-Si-(Al)-O-(N)] glasses have a large number of potential applications due to their physical properties. LÄS MER

7. 25. Molecular Modeling of Cardiolipin

   Författare :Martin Dahlberg; Arnold Maliniak; Richard W. Pastor; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physical chemistry; Fysikalisk kemi; fysikalisk kemi; Physical Chemistry;

   Sammanfattning : Biological membranes are assembled from many different lipids. Our understanding of membrane function and morphology is dependent on linking the properties of the lipids to the properties of the membranes. LÄS MER