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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.
341

Enhancing membrane processes for water reuse

Parameshwaran, Kathiravelu, Chemical Sciences & Engineering, Faculty of Engineering, UNSW January 2008 (has links)
The study reported here was aimed at optimising the microfiltration (MF) membrane process applied to water reclamation. Polypropylene hollow fibre membrane (0.2 ??m) with high pressure backwahing was mainly used in this study. To obtain secondary effluent for microfiltration a biological treatment (UASB/SBR) was applied to brewery effluent. It was identified that loading at a rate below 14 kg COD/kLd will ensure the stable performance of UASB. An initial energy balance of the system (Biological and MF) shows a plant treating brewery effluent (4000 mg/L COD) could yield a net energy of 2.5 kWh/kL (yield from methane less the plant operating energy) at an optimised MF flux. For the MF of low solids feed it was found that crossflow has no benefit and that intermittent dead end filtration is less productive than dead-end cycles. It was also that found cycle time between air backwashes is strongly dependent on the imposed flux and the maximum TMP allowed. Analysis based on energy and capital cost indicates that if energy saving is the objective the unit needs to be operated at low imposed flux. However, if capital and energy costs are combined, cost efficient operation would be at about 60 to 70 L/m2.h for TMPmax of 20 kPa or above 80 L/m2.h for TMPmax of 50 kPa. For cycles with a TMPmax of 20 kPa, the specific cake resistance was constant over the range of imposed fluxes. However, for a TMPmax of 50 kPa the specific resistance was higher and increased with imposed flux, signifying compressible cake formation. Further analysis of the TMP profiles showed that the membrane resistance increased over a number of cycles and that the increase was higher at higher flux. To fully optimise the operation, it would be necessary to include these factors. Laboratory scale studies with yeast showed many similarities with secondary effluent filtration. However, some inconsistencies were observed at lower f1uxes, which need to be confirmed by further studies. Life cycle assessment of the membrane filtration process indicated that operating at low flux (10 Llm2.h) with higher TMPmax is the environmentally sound operational strategy. The analysis highlights the fact that the environmental impacts mainly come from the membrane operation (more than 85%). When alternative energy sources are considered, the least impact operational strategy shifts towards higher flux (in the vicinity of 30 l/m2.h). In-situ electrochemical cleaning using an electrolysis process indicated better flux recovery than traditional chemical cleaning. However, repeated cycles of fouling and cleaning showed electrochemically cleaned membranes have a higher fouling tendency than the chemically cleaned membrane. Initial characterisation of membrane surface properties after cleaning could not provide conclusive evidence for the cause of rapid fouling of the electrochemically cleaned membrane.
342

An investigation of carbohydrate-reactive outer membrane proteins of mesophilic aeromonads

Quinn, Diana Marie January 1995 (has links)
Thesis (PhD (Health Science) in Medical Laboratory Science)--University of South Australia, 1995
343

Outer membrane protein immunity to Pasteurella pneumotropica and the interaction of allergy

See, Sarah Bihui January 2010 (has links)
[Truncated abstract] Infectious and allergic diseases of the respiratory tract are major contributors to global mortality, morbidity and economic burden. Bacterial infections such as pneumonia and otitis media are important diseases, especially in children, while allergic diseases such as asthma and allergic rhinitis afflict up to 30% of the world's population. A confounding aspect of respiratory disease is the evidence of a complex relationship between respiratory allergy and respiratory infection, with infection suggested to both promote and prevent the pathogenesis of allergic disease. Additionally, allergy is a risk factor for bacterial infection such as otitis media, pneumonia and sinusitis, while respiratory infection can exacerbate allergic symptoms. Given the burden of bacterial respiratory disease and respiratory allergy, the development of preventative treatments for these diseases is needed and will benefit from clearer knowledge of the underlying immune mechanisms. This thesis aimed to to extend current knowledge by using Pasteurella pneumotropica, a similar bacteria to the human pathogen nontypeable Haemophilus influenzae (NTHi), to study respiratory infection and protective anti-outer membrane protein (OMP) immunity as well as the interaction of respiratory infection and allergic inflammation. Homologues of the important NTHi vaccine candidates P4, P6, P26 and D15 were found to be encoded by P. pneumotropica and a high level of amino acid sequence identity was noted between the different P. pneumotropica strains, as well as between other Pasteurellaceae members. ... In contrast, anti-P6his serum antibodies transferred to naïve mice did not confer protection. These results suggested that T-cell–mediated mechanisms were involved in P6his-mediated protection, and showed that the P. pneumotropcia model was useful for elucidating protective mechansims. The interaction of P. pneumotropica infection and papain-induced allergy was studied to investigate immune mechanisms underlying respiratory infection and allergy. Mice with ongoing allergic inflammation were intranasally challenged with bacteria and exhibited reduced pulmonary bacterial numbers, prolonged eosinophilia in the lungs and the induction of Th2 cytokines in the BALF, compared to nonallergic, infected mice. This suggested a protective role for allergic inflammation in this model. The effect of papaininduced inflammation on mice colonised by P. pneumotropica was also examined and allergic inflammation appeared to worsen infection in colonised mice. This suggested that allergic inflammation may also have a role in promoting infection in this model. In conclusion, this thesis explored mechanisms involved in vaccine-mediated immunity and the interaction of respiratory infection and allergy using a P. pneumotropica infection in its natural host. It was shown that intranasally administered recombinant P6 and P4 protected mice from lung infection, which justifies the inclusion of these OMPs as NTHi vaccine candidates. Additionally, it was demonstrated that the interaction of allergy and respiratory infection modulated immune responses. Overall, these results emphasize that a clearer understanding of the complex mechanisms underlying these interactions is required, and may be aided by the development of suitable animal models.
344

Studies on the TolC protein of Escherichia coli K-12 and its effect on OmpF expression /

Misra, Rajeev. January 1986 (has links) (PDF)
Thesis (Ph. D.)--University of Adelaide, Dept. of Microbiology and Immunology, 1986. / Includes bibliographical references.
345

Dynamic modeling of polymer electrolyte membrane fuel cell stack with 1D and 2D CFD techniques

Shan, Yuyao, Choe, Song-Yul. January 2006 (has links) (PDF)
Thesis(M.S.)--Auburn University, 2006. / Abstract. Vita. Includes bibliographic references.
346

Conformational properties of transmembrane polypeptide segments in the ER membrane /

Nilsson, IngMarie, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 8 uppsatser.
347

Fouling mechanisms in the membrane filtration of single and binary protein solutions /

Chan, Robert. January 2002 (has links)
Thesis (Ph. D.)--University of New South Wales, 2002. / Also available online.
348

Monolithic integration of proton exchange membrane microfuel cells /

Xiao, Zhiyong. January 2008 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2008. / Includes bibliographical references. Also available in electronic version.
349

Design, development and application of new technological approaches in subcellular proteomics

Gauthier, Daniel, January 1900 (has links)
Thesis (Ph.D.). / Written for the Division of Experimental Medicine. Title from title page of PDF (viewed 2008/05/09). Includes bibliographical references.
350

Simulation of a membrane reactor for ammonia decomposition /

Kraisuwansarn, Nichakorn. January 1991 (has links)
Thesis (M.S.)--Oregon State University, 1992. / Typescript (photocopy). Includes bibliographical references (leaves 82-85). Also available on the World Wide Web.

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