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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Fundamentals of drop coalescence in crude oil

Stoyel, Jason Alexander January 2000 (has links)
No description available.
2

Lipase-catalysed reactions in W/O microemulsion systems

Carlile, Katherine January 1998 (has links)
No description available.
3

Temperature insensitive microemulsions

Taylor, Diana Jacqueline Falcon January 1999 (has links)
No description available.
4

The Fairfax County Water Authority response to the Colonial oil spill of March 28, 1993 /

Bonacquisti, Thomas P. January 1994 (has links)
Report (M.S.)--Virginia Polytechnic Institute and State University, 1994. / Abstract. Includes bibliographical references (leaves 52-53). Also available via the Internet.
5

Sorption and transport of water vapour in Acrylic Paints/

Topçuoğlu, Özge. Alsoy Altınkaya, Sacide January 2004 (has links) (PDF)
Thesis (Master)--İzmir Institute of Technology, İzmir, 2004. / Includes bibliographical references (leaves. 70-73).
6

Evaluation of Novel Strategies for the Inclusion of Sodium Chloride in Liquid Foods

Rietberg, Matthew Rodney 22 December 2011 (has links)
This thesis investigated the perception of salt taste in two novel strategies for inclusion of NaCl in liquid foods: water-in-oil (w/o) emulsions and mucoadhesive biopolymer solutions. The major factors influencing w/o emulsion stability and perception were evaluated and a response surface model was developed. The amount of dispersed aqueous phase was the most significant factor affecting stability and perception. NaCl stabilized the emulsions and depressed salt sensory perception at elevated concentrations due to its interaction with the emulsifier polyglycerol polyricinoleate. Future research should elaborate events during oral processing of w/o emulsions. Biopolymer mucoadhesive character and concentration effects were also investigated. Mucoadhesion did not enhance salt taste. Above c*, there was a significant depression of sensory intensity, enhanced in polymers with hyperentanglements in solution. The depressive concentration effect may mask the effects of mucoadhesion. Future research should also inspect the influence of thickened hydrocolloid microstructure on perception. / The Advanced Foods and Materials Network
7

Role of Biodegradable Ethyl Cellulose in Bitumen Production

Hou, Jun Unknown Date
No description available.
8

Immersed membrane bioreactors for produced water treatment

Brookes, Adam January 2005 (has links)
The performance of a submerged membrane bioreactor for the duty of gas field produced water treatment was appraised. The system was operated under steady state conditions at a range of mixed liquor suspended solids (MLSS) concentrations and treatment and membrane performance examined. Organics removal (COD and TOC) display removal rates between 90 and 97%. Removal of specific target compounds Benzene, Toulene, Ethylbenzene and Xylene were removed to above 99% in liquid phase with loss to atmosphere between 0.3 and 1%. Comparison of fouling rates at a number of imposed fluxes has been made between long term filtration trials and short term tests using the flux step method. Produced water fed biomass displays a greater fouling propensity than municipal wastewater fed biomass from previous studies. Results indicate an exponential relationship between fouling rate and flux for both long and short term trials, although the value was an order of magnitude lower during long term tests. Moreover, operation during long term trials is characterised by a period of pseudo stable operation followed by a catastrophic rise in TMP at a given critical filtration time (tfi, ) during trials at 6 g. L"1. This time of stable operation, tfit, is characterised by a linear relationship between fouling rate and flux. Results have been compared with the literature. Data for membrane fouling prior to the end of t fit yielded a poor fit with a recently proposed model. Trends recorded at t> trlt revealed the fouling rate to follow no definable trend with flux. The system showed resilience to free oil shocking up to an oil concentration of 200ppmv. Following an increase in oil concentration to 500 ppmv, rapid and exponential fouling ensued.
9

A multidisciplinary approach to structuring in reduced triacylglycerol based systems

Wassell, Paul January 2013 (has links)
This study (Wassell & Young 2007; Wassell et al., 2010a) shows that behenic (C22:0) fatty acid rich Monoacylglycerol (MAG), or its significant inclusion, has a pronounced effect on crystallisation (Wassell et al., 2010b; 2012; Young et al., 2008) and interfacial kinetics (3.0; 4.0). New interfacial measurements demonstrate an unusual surface-interactive relationship of long chain MAG compositions, with and without Polyglycerol Polyricinoleate (PGPR). A novel MAG synthesised from Moringa oleifera Triacylglycerol (TAG) influenced textural behaviour of water-in-oil (W/O) emulsions and anhydrous TAG systems (4.0: 5.0; 6.0). Emulsifier mixtures of PGPR and MAG rich in C18:1 / 18:2 and C16:0 / C18:0 do not decrease interfacial tension compared with PGPR alone. Only those containing MAG with significant proportion of C22:0 impacted interfacial behaviour. A mixture of C22:0 based MAG and PGPR results with decreasing tension from ~20°C and is initially dominated by PGPR, then through rearrangement, the surface is rapidly dominated by C22:0 fatty acids. A Moringa oleifera based MAG showed unusual decreased interfacial behaviour not dissimilar to PGPR. All other tested MAG (excluding a C22:0 based MAG), irrespective of fatty acid composition resulted with high interfacial tension values across the measured temperature spectrum (50°C to 5°C). A relative decrease of interfacial tension, with decreased temperature, was greater, the longer the chain length (Krog & Larsson 1992). Moreover, results from bulk and interfacial rheology showed that the presence of C22:0 based MAG has a pronounced effect on both elastic modulus (G’) and viscous modulus (G’’). Through a multidisciplinary approach, results were verified in relevant product applications. By means of ultrasonic velocity profiling with pressure difference (UVP-PD) technique, it was possible to examine the effect of a C22:0 based MAG in an anhydrous TAG system whilst in a dynamic non-isothermal condition (3.0). The non-invasive UVP-PD technique conclusively validated structural events. The application of a Moringa oleifera based MAG in low TAG (35% - 41%), W/O emulsions, results in high emulsion stability without a co-surfactant (PGPR). The bi-functional behaviour of Moringa oleifera based MAG is probably attributed to miscibility (Ueno et al., 1994) of its fatty acids, ranging ~30% of saturated fatty acids (SAFA), with ~70% of C18:1 (5.0). It is concluded that the surface-interactive behaviour of Moringa oleifera based MAG, is attributed to approximately 10% of its SAFA commencing from C20:0. When examined separately and compared, results showed that physical effect of a Moringa oleifera based MAG was not dissimilar to PGPR, influencing the crystallisation kinetics of the particular anhydrous TAG system. When either was combined with a C22:0 rich MAG, enhanced gelation onset and strong propensity to form dendrite structure occurred (5.0). Macrobeam and synchrotron radiation microbeam small angle x-ray diffraction (SR-μ-SAXD) was utilized (6.0) to assess behavior of C22:0 rich MAG, with and without PGPR (Wassell et al., 2012). The C22:0 based MAG combined with PGPR promoted TAG crystallisation as observed by differential scanning calorimetry (DSC). Polarised optical microscopy (POM) observations indicated that C22:0 based MAG eliminates formation of large crystal aggregates, resulting in the likely formation of tiny Pickering TAG / MAG crystals (6.0). It is concluded that the presence and interactive behaviour of Pickering surface-active MAG, is strongly linked to increased fatty acid chain length, which induce increased textural resilience owing to viscoelasticity (4.0; 5.0). A multidisciplinary approach was able to verify structuring behaviour (4.0; 5.0), using multiple analyses (Wassell et al., 2010b; 2012; Young et al., 2008). Novel structuring solutions in reduced TAG based systems have been provided (4.0; 5.0). This study both enhances current understanding of structuring in low TAG W/O emulsions and has led to novel MAG compositions, which address emulsification, structuring and texture in TAG based food systems (Wassell et al., 2010a; 2012a; 2012b; 2012c; 2012d; 2012e; Bech et al., 2013).
10

Polyolefin membranes with renewable bio-based solvents: From plastic waste to value-added materials

Ramírez Martínez, Malinalli 11 1900 (has links)
The polyolefins production is the largest among all types of plastics given their thermal and chemical stability and low cost, which allows them to be used in a wide variety of products worldwide, including polypropylene (PP) and polyethylene (PE) membranes. However, the small percentage of polyolefins being recycled compared to the enormous amount produced has led to severe environmental pollution issues. In addition, the traditional polyolefin membrane fabrication methods utilize mostly toxic non-renewable solvents such as xylenes at high temperatures, causing further negative environmental impact. The objective of this study is to propose a greener alternative for polyolefins in general and in particular for membrane fabrication. For this, two bio-based solvents (α-pinene and Dlimonene) were proposed to dissolve PP and LDPE, and the resulting films and membrane properties were studied. Hydrophobic PP microporous membranes were obtained by thermally induced phase separation from pristine commercial polymers and plastic waste. They were applied for water-in-toluene emulsion separation. The water rejection was above 95% for membranes fabricated from dope solutions containing 25% pristine PP and 30% waste PP heated at 130°C, suggesting that they could be used in oil spill recovery operations. This work aims to contribute to the implementation of more sustainable practices in the membrane industry.

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