Sökning: "29Si-NMR"
Hittade 3 avhandlingar innehållade ordet 29Si-NMR.
1. Aqueous behaviour of characteristic molecules in the synthesis of porous silica materials : - an atomistic description
Sammanfattning : The formation process of porous silica materials is an intricate process, involving a number of components that interact to form a highly organized material. Both zeolites and mesoporous silica materials typically require the presence of organic structure director agents (SDAs) around which the silica network polymerizes. LÄS MER
2. Nuclear magnetic resonance studies on bentonite in complex mixed systems
Sammanfattning : In this work 23Na MAS NMR was validated as a successful quantitative method for studies of exchanging sodium in bentonites useful, in particular, for studies of ion-exchange kinetics. Na-enriched bentonites equilibrated in a re-circulated process water at iron-oxide pelletizing plants may acquire properties of Ca-bentonites after already 20 minutes of the equilibration time, since >50 % of sodium ions will be exchanged by calcium ions during first minutes of bentonite placed in contact with the process water. LÄS MER
3. Transition metal-catalyzed allylic and vinylic functionalization : Method development and mechanistic investigations
Sammanfattning : The use of small molecule building blocks in, for example, pharmaceutical research and new material development, creates a need for new and improved organic synthesis methods. The use of transition metals as mediators and catalysts opens up new reaction pathways that have made the synthesis of completely new compounds possible as well as greatly improved the synthetic routes to known compounds. LÄS MER