AlcellRTMlignin has been used commercially in adhesive preparation and brake pad linings and experimentally in animal feeds to reduce or eliminate diarrheal attacks in farm animals. Our study dealt with elucidating the antibacterial effect of AlcellRTMlignin. It would appear that adsorbance of E. coli cells to AlcellRTMlignin particles is not essential for destruction of the organism. / The antibacterial activity was delayed by the inclusion of Mg 2+ ions in the AlcellRTMlignin filtrate or in the enumeration medium (BHIA). Addition of bile salts to the enumeration medium (BHIA) enhanced the culturability loss of E. coli cells suspended in the filtrate of AlcellRTMlignin. Using FTIR methodology, it appears, that compounds of AlcellRTMlignin affect phospholipid-phospholipid and/or phospholipid-protein interactions in bacterial membranes, causing the patching of membrane phospholipids and proteins. / Additional studies are necessary to evaluate interactions of compounds of AlcellRTMlignin with bacterial cells.

The physical properties of rigid PVC products can be related to formulation, preblending and processing characteristics. A fuller understanding between these interrelations involves investigation of a complete processing system from powder additives to end product. A knowledge of these relationships can lead to a optimisation of formulation aspects and processing conditions. Fillers and lubricants have often been incorporated into PVC compounds on a empirical basis, however in this investigation a wide range of compositions were carefully chosen and included a calcium carbonate filler at levels up to 40 phr. These were dry blended and then characterised by bulk density and filler content. The premix was processed using an instrumented twin screw extruder, a wide processing 'window' being chosen to provide a product range with large variations in fusion level. Further compounds were extruded, incorporating two different impact modifiers. The extrudates was assessed for degree of fusion by differential thermal analysis, solvent immersion and microscopy. The filler distribution, surface appearance and residual grain structure was observed using a range of microscopy techniques and the results related to operating conditions. A measure of fusion level was obtained from mast er curves of heat of fusion versus processing temperature'. The filler level did not influence the degree of fusion. Various mechanical properties of the pipe were assessed. Impact performance was measured using an instrumented falling weight impact tester and the subsequent fracture behaviour depended on the composition and fusion level. Impact properties were dramatically reduced at a critical filler content and ductile-brittle transition temperatures were obtained for the extrudates by testing at low and high temperatures. Tensile properties did not follow the trends observed during impact testing but indicated a progressive reduction in tensile properties with increasing filler content.

No description available.

Graduation date: 1961

Thesis (M.S.)--University of Hawaii at Manoa, 2006. / Includes bibliographical references (leaves 113-114). / xi, 132 leaves, bound ill. 29 cm

The search for a new environmentally friendly construction material that will match the durability of ancient concrete has stimulated interest in geopolymerisation in recent times. Despite extensive research that has been conducted on various aspects of geopolymerisation, especially in enhancing the properties of resultant binders and understanding the chemical mechanisms involved, a number of questions remain to be answered. The role of calcium in geopolymerisation is one of them. It is known that the presence of a moderate amount of calcium in a geopolymeric binder will improve the resultant compressive strength. However, it is still unclear whether calcium will play a charge-balancing role within the aluminosilicate structure (to maintain electro-neutrality in a similar way as alkali metal cations, Na+ or K+, or perhaps an alternative role). In addition, the role of calcium in geopolymerisation is of great interest because it is proposed for the first time that calcium links geopolymer chemistry to, and distinguishes it from, ordinary Portland cement (OPC). (For complete abstract open document)

Thesis (M.S.)--Auburn University, 2007. / Abstract. Vita. Includes bibliographic references.

Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2004. / Härtill 3 uppsatser.

Thesis (M. Sc.)--University of Western Sydney, Hawkesbury, (1994). / Includes bibliographical references and index.

Dissertation (Ph.D.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.