Support for a Dioxyallyl Cation in the Mechanism Leading to (-)-Levoglucosenone.

Levoglucosenone (LGO) is the major product formed when cellulose is pyrolyzed in the presence of acid at temperatures between 170 and 350 °C. The current intense interest in biomass conversion has led to a number of reports on its preparation; however, there is still uncertainty on the mechanism leading to LGO. We propose a new mechanism which involves a C2-C1 hydride shift followed by intramolecular trapping of a dioxyallyl cation.

Intelligent Approach to Solvent Substitution: The Identification of a New Class of Levoglucosenone Derivatives.

With the increasing restriction and control of hazardous solvents, safer alternatives need to be identified. Here a contemporary approach to solvent selection and substitution is presented that offers a more scientific alternative to the simple "like-for-like" exchange. A new family of levoglucosenonederived compounds is proposed, modeled to determine their solvent properties, synthesized, and tested.

Smooth deuterated cellulose films for the visualisation of adsorbed bio-macromolecules.

Novel thin and smooth deuterated cellulose films were synthesised to visualize adsorbed bio-macromolecules using contrast variation neutron reflectivity (NR) measurements. Incorporation of varying degrees of deuteration into cellulose was achieved by growing Gluconacetobacter xylinus in deuterated glycerol as carbon source dissolved in growth media containing DO. The derivative of deuterated cellulose was prepared by trimethylsilylation(TMS) in ionic liquid(1-butyl-3-methylimidazolium chloride).

Dihydrolevoglucosenone (Cyrene) as a bio-based alternative for dipolar aprotic solvents.

Dihydrolevoglucosenone (Cyrene) is a bio-based molecule, derived in two simple steps from cellulose, which demonstrates significant promise as a dipolar aprotic solvent. The dipolarity of dihydrolevoglucosenone is similar to NMP, DMF and sulpholane. Dihydrolevoglucosenone demonstrates similar performance to NMP in a fluorination reaction and the Menschutkin reaction.

Surface topography of kenaf (Hibiscus cannabinus) sized papers.

Bleached kenaf handsheets sized with different polymers such as chitosan, polyvinyl alcohol and cationic starch, were used for the determination of surface topography. A non-contact profilometer, the AltiSur 500, was used to characterize the topography of structural details in the paper surface. Numerical and visual characterization of surface roughness indicated that the surface of chitosan-sized paper was less rough than other surfaces, and all the sized papers were commonly smoother than the unsized paper.