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The experimental determination of the diffusivity of carbon dioxide (CO2) in an amine solvent is difficult as the CO2 diffuses and reacts simultaneously when absorbed into an amine solvent. As the knowledge of the diffusivity and solubility of CO2 is essential to design the absorption units based on amine solvents, the nitrous oxide (N2O) analogy is used in practice to estimate them. It consists of evaluating those physical properties by substituting the reacting CO2 with an inert gas of a similar structure, N2O. The diffusion of CO2 in amine solvents is investigated using molecular dynamics (MD) simulation. Unlike experiments, MD simulation allows a direct measurement of the CO2 diffusivity. In MD simulations, the reaction between CO2 and the amine can be switched off. The Fick diffusion coeffcients are derived from the Maxwell-Stefan diffusivities and the thermodynamic factors. Different amine solvents like monoethanolamine, diethanolamine, methyl-diethanolamine and ethylamine are investigated. The N2O analogy in the monoethanolamine-water solution has been validated.

Implementing the program of the planned extension Westergouwe to contribute to the urban regeneration of different neighbourhoods in Gouda.

Part of the studio renewal of the urban renewal. A hybrid program with a station and a market is aiming to have an effect on the scale of the neighbourhood (Schilderswijk/Laakkwartier).

A method of determining a structure parameter of a target on a substrate is disclosed. Illuminating a first region of the target with a first beam of coherent radiation and measuring a diffraction intensity pattern. Shifting the relative position between the target and the projection system to offset a second region to be illuminated from the first region. Illuminating the second region, offset from and overlapping with the first region, and measuring a diffraction intensity pattern. Repeating until the whole portion of interest of the target has been illuminated once, with adjacent illumination spots having some physical overlap. Retrieving phase information from the measured intensity patterns. Modeling the target to calculate a modeled diffraction intensity pattern and modeled phase information. Determining the structure parameter of the target by comparing the measured diffraction intensity patterns and the retrieved phase to the calculated modeled diffraction intensity pattern and the modeled phase information.

The combination of conventional unit operations with pervaporation or vapour permeation membrane separation processes offers opportunities for process intensification in terms of augmenting capacity and decreasing energy consumption of conventional unit operations. The MTBE production process is an often studied example of a so-called hybrid process in which distillation is combined with pervaporation or vapour permeation. In this work transport of pure methanol through and separation of methanol from MTBE by a supported microporous methylated membrane (developed by the Energy research Centre of the Netherlands) is studied. Several aspects of modelling of transport through the support layers and the selective layer are addressed, thereby comparing the Maxwell-Stefan equations for pure methanol transport with a practical engineering model. From experiments performed at temperatures up to 140°C it appeared that both the selectivity towards methanol and flux of the membrane are high. The thesis ends with a study comparing pervaporation and vapour permeation on laboratory scale as well as on large scale by simulations.

Clean water is becoming a scarce resource. As a consequence reclaimed wastewater can be an attractive alternative to replace existing water resources for non-potable reuse options. In order to achieve this goal advanced treatment technologies are required. An example of such technology is the membrane bioreactor (MBR) process. In the MBR process the biomass (activated sludge) that biologically degrades the pollutants in wastewater is separated from the purified water (effluent) by an advanced membrane filtration step, instead of the conventional sedimentation step. The superior effluent quality that can be achieved with MBR technology offers possibilities for reuse options such as irrigation and industrial process water. Application of the MBR process is however restrained by the relatively high operation and maintenance costs, related to the problem of membrane fouling (accumulation of substances on the membrane and the accompanying decrease of the system performance). In order to make MBR technology a feasible alternative more knowledge about the fouling process is required. In the research described in this thesis a method used to characterise the filterability of activated sludge is discussed and applied at full-scale MBR plants in the Netherlands. In addition the factors the influence the filterability are analysed. This is important, because good filterability forms the starting-point for an efficient MBR filtration process.

The performance of opto-electronic devices based on semi-conducting organic molecules, dependence on the molecular order of the semi-conducting molecules. To get high charge transportation through the material a high order of the material is needed. In our research we used liquid crystalline phases to get relative high order over large distances. A series of all-aromatic phenyl-thiophene pentamers and a series of alkoxy terminated phenyl-thiophene pentamers have been synthesized. The mesophase behaviour and the UV-vis absorption have been determined. In the nematic phase the molecules possess only orientational order. It was found that the orientational order, in the nematic phase of p-quinquephenyl, determined by wide angle x-ray diffraction is less, due to temperature dependent fluctuations of the director at a macroscopic scale. The exact temperature dependence of the orientational order was determined by birefringence measurements and could be fitted with the predicted temperature dependence of the orientational order by the Maier-Saupe model. In the smectic phases the molecules possess orientational order as well as positional order. The charge mobility was determined by time resolved microwave conductivity. In the nematic phase the charge mobility is dependent on the orientational order. Hardly any charge mobility could be observed in the higher ordered smectic phases, because the concentration of charges is reduced.