This week we have two theses which are nailed to the birch trees at the library. THe first one was at 2pm and the other will be at 3pm.
Hamidreza Barghi, School of Engineering, makes his thesis Functionalization of Synthetic Polymers for Membrane Bioreactors, available at the library at 2pm today.
Abstract:
“Membrane bioreactors (MBRs) show great promise for productivity improvement and energy conservation in conventional bioprocesses for wastewater reclamation. In order to attain high productivity in a bioprocess, it is crucial to retain the microorganisms in the bioreactors by preventing wash out. This enables recycling of the microorganisms, and is consequently saving energy. The main feature of MBRs is their permeable membranes, acting as a limitative interface between the medium and the microorganisms. Permeation of nutrients and metabolites through the membranes is thus dependent on the membrane characteristics, i.e. porosity, hydrophilicity,and polarity. The present thesis introduces membranes for MBRs to be used in a continuous feeding process, designed in the form of robust, durable, and semi-hydrophilic films that constitute an effective barrier for the microorganisms, while permitting passage of nutrients and metabolites. Polyamide 46 (polytetramethylene adipamide), a robust synthetic polymer, holds the desired capabilities, with the exception of porosity and hydrophilicity. In order to achieve adequate porosity and hydrophilicity, bulk functionalization of polyamide 46 with different reagents was performed. These procedures changed the configuration from dense planar to spherical, resulting in increased porosity. Hydroxyethylation of the changed membranes increased the surface tension from 11.2 to 44.6 mJ/m2. The enhanced hydrophilicity of PA 46 resulted in high productivity of biogas formation in a compact MBR, due to diminished biofouling. Copolymerization of hydrophilized polyamide 46 with hydroxymethyl 3,4-ethylenedioxythiophene revealed electroconductivity and hydrophilic properties, adequate for use in MBRs. To find either the maximal pH stability or the surface charge of the membranes having undergone carboxymethylation, polarity and the isoelectric point (pI) of the treated membranes were studied by means of a Zeta analyzer. The hydroxylated PA 46 was finally employed in a multilayer membrane bioreactor and compared with hydrophobic polyamide and PVDF membranes. The resulting biogas production showed that the hydroxylated PA 46 membrane was, after 18 days without regeneration, fully comparable with PVDF membranes.”
Anne-Britt Torkildsby, School of Textiles, will make her thesis Existential design – revisiting the dark side of design thinking, available at the library at 3pm.
Abstract:
“This thesis aims to discuss ways of opening up the design brief when designing for extreme environments such as intensive care units and remand prisons. Focusing on “designials” (fundamental forms of design being), the methodology intends to illustrate the fact that objects may directly impinge upon certain “existentials” (fundamental forms of human being). Moreover, the method is a form of critical design that enables designers to shift focus, from analysis of the functionality of a design in use, e.g. by performing a functional analysis, to analysis of the form of being human that a design in use defines. More importantly, this thesis considers what may happen if we do not take into account this aspect of design; in other words, the “dark side” of design thinking.”
PIeta Eklund