Anders Rasmuson

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Steam explosion is a process used to enhance enzyme penetration and digestibility of wood. Wood chips are processed with high-pressure steam for a limited time, and the bonding between polysaccharides and lignin is weakened. After this processing, the pressure is rapidly reduced to induce steam explosion where the vapor inside a fiber expands and exerts(More)
Heat transfer in vial lyophilization has been studied experimentally and theoretically as a first step in developing a theoretical model for vial lyophilization. Heat transfer was studied by cooling and heating sealed vials containing water in a pilot scale freeze-dryer. The factors studied were bottom curvature of the vial, chamber pressure, fill volume,(More)
Purpose. The purpose of this work was to demonstrate the feasibility of using near-infrared spectroscopy (NIRS) to monitor the freeze-drying process in-situ. Methods. The experiment was performed in a pilot-scale freeze-dryer, in which the NIRS probe was interfaced using a lead-through to the lyophilizer. Special equipment for the sample presentation was(More)
For disintegrating tablet formulations, deaggregation of small particles is sometimes one of the rate-limiting processes for drug release. Because the tablets contain particles that are in the colloidal size range, it may be assumed that the deaggregation process, at least qualitatively, is governed by Brownian motion and electrostatic and van der Waals(More)
Spectral peak area analysis has in this study been shown to be a viable method in near-infrared spectroscopy (NIRS) moisture assays. The study also shows that the required number of calibration samples can be minimized, and the method is, therefore, especially suitable for moisture assays in early formulation development and in-situ process monitoring.(More)
Steam explosion (SE) pretreatment produces damaged and disintegrated biomass with a large surface area which facilitates enzymatic hydrolysis for the production of biofuels and other value-added chemicals. It was observed during experiments that wood chips disintegrate into smaller pieces because of collisions and impact with each other and the walls of the(More)
This study exploits the mechanisms governing blending of adhesive mixtures, i.e. random mixing, de-agglomeration and adhesion, and their relative importance to achieve mixing homogeneity. To this end, blending of micronized particles (fines) with carrier particles was carried out using a high shear mixer. Dry particle sizing using laser diffraction coupled(More)
Bordered pits connect adjacent tracheid cells in softwoods and enable water transport between them. Knowledge of how large molecules, such as polysaccharides and enzymes, are transported through pits is important to understand the extraction process of valuable biopolymers from wood. The main mass transport mechanism for large dissolved molecules in wood is(More)
A methodology for studying flow in heterogeneous soft microstructures has been developed. The methodology includes: (1) model fractal or random heterogeneous microstructures fabricated in PDMS and characterised using CLSM; (2) μPIV measurements; (3) Lattice-Boltzmann simulations of flow. It has been found that the flow behaviour in these model materials is(More)