23,922 results for Thesis

  • Shear work induced changes in the rheology of model Mozzarella cheeses : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Manawatu, New Zealand

    Sharma, Prateek (2016)

    Doctoral thesis
    Massey University

    Mozzarella cheese is a pasta filata type of cheese. Its manufacture includes a kneading – stretching step that creates a fibrous protein network and distributes fat-serum channels to attain desirable melt functionality on a pizza. During processing and manufacturing of pasta-filata cheese, large deformations take place. For appropriate characterization of a food material, rheological evaluation should be conducted in similar operating conditions, length scales and time scales to those taking place in the actual process. Development of the typical fibrous pasta-filata structure of mozzarella cheese depends on composition and process variables. Critical process variables in the development of cheese structure are time, temperature and shear. In this study we studied the effect of shear work on rheology, structure and melt functionality of model Mozzarella cheese. Three types of model cheeses (full-fat, non-fat and full-fat with added tri-sodium citrate) were prepared by working cheese components together at 70 oC in a twin screw Blentech cooker. Varied amounts of shear work input (2.8-185 kJ/kg) were given to the cheese samples using 50, 150 and 250 rpm screw speeds. Samples were subjected to a range of rheological tests, confocal laser scanning microscopy, fat particle size measurements (DLS) and melt functionality evaluation. While measuring steady shear viscosity of Mozzarella-type cheeses in a rotational rheometer at 70oC, three main difficulties were encountered; wall slip, structural failure during measurement and viscoelastic time dependent effects. A flow curve method was successfully devised to measure steady shear rheology by using serrated plates as surface modification to avoid wall slip, giving enough measurement duration at low shear rate to avoid viscoelastic effects and selecting limited shear steps to cause minimum structural changes. These techniques enabled successful measurement of steady shear viscosity of molten Mozzarella-type cheeses at 70oC at shear rates up to 250 s-1. Strong work thickening was observed for full fat Mozzarella cheese from steady shear rheology, oscillatory rheology, creep, elongational viscosity and tensile testing data. Steady shear rheology and melt functionality were found to be strongly dependent on total shear work input. An exponential increase in consistency coefficient (K from power law model) was observed with increasing amounts of accumulated shear work, indicating work thickening behaviour. An exponential work thickening equation is proposed to describe this behaviour. Excessively worked cheese samples exhibited liquid exudation, poor melting and poor stretch. Nonfat cheese exhibited similar but smaller changes after excessive shear work input. At lower shear work inputs (70 kJ/kg) it behaved like a viscoelastic solid with low frequency dependence. A definite critical point for structural and viscoelastic transition was identified at a medium shear work level (~ 58 kJ/kg at 150 rpm). Similar viscoelastic property changes occurred in non-fat cheese suggesting that major changes were taking place in the protein matrix during working. Confocal microstructures plus macroscopic observations showed systematic changes in structure with increased shear work inputs with unmixed buttery liquid observed at 58 kJ/kg. At very high shear work inputs, > 75 kJ/kg, striations or anisotropy in the microstructures had disappeared and small micro-cracks were evident. Volume-weighted mean fat particle size decreased with shear work input and particle size distributions also changed. To account for the short and long term relaxation response behaviour, a 4-element Burger‘s model was found adequate for fitting the creep data of model cheese at 70 oC but a 6-element model was required at 20 oC. As shear work input increased, retarded compliance decreased and zero shear viscosity increased indicating the more elastic behavior of the cheeses with higher shear work input. Fracture stress and strain for longitudinal samples from elongated full fat cheese did not vary significantly with shear work input up to 26.3 kJ/kg then decreased dramatically at 58.2 kJ/kg. Longitudinal samples with shear work input G‘ > elongational viscosity > consistency coefficient, K. It was concluded that the dominant contributor to the changes in rheology, structure and melt properties with increased shear work was shear induced structural changes to the protein matrix. An increase in calcium induced protein-protein interactions after high shear work at 70 oC. In summary, this thesis provides useful insights to shear work induced changes in material properties. It proposes useful linkages between the manufacturing process and the application of model Mozzarella cheese using appropriate rheological methods. Since the linkages were validated for only one composition and in only one processing environment, it is proposed that they should be tested in other conditions. In order to build a more complete picture, a molecular level study is proposed for future work to elucidate chemical changes during working and find appropriate linkages with physical and functional characteristics.

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  • R² and stock price informativeness : new empirical evidence : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Finance at Massey University, Palmerston North, New Zealand

    Hao, Wei (2015)

    Doctoral thesis
    Massey University

    Abstract taken from Introduction (page 7)

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  • The Invention of Papahurihia : A thesis submitted in fulfilment of the requirements of the degree of Doctor of Philosophy in History at Massey University, Albany, New Zealand

    Ward, Judith (2016)

    Doctoral thesis
    Massey University

    Historians portray Papahurihia as the first Māori prophet and founder of a syncretistic religion that combined elements of Judaic and Christian theology with Māori beliefs. They also say he observed a Saturday Sabbath and that his followers were known as Jews. This thesis disputes those conclusions. It re-examines the commentaries of the CMS missionaries in the Bay of Islands from the context of 1830s Protestant evangelicalism and draws on the texts of the Wesleyan and Roman Catholic missionaries and European settlers to show how Papahurihia behaved in various situations. It argues that historians have failed to take account of the way that Protestant and Catholic writers saw Papahurihia through the lenses of their own religions. The thesis recreates Papahurihia in the context of the Ngāpuhi seasonal cycle and links him to the persistence of ceremonies like the hahunga. It argues that historians have overlooked the extent to which he operated on a Māori concept of time and how the missionaries and Europeans made assumptions about the behaviour of Papahurihia and his followers based on the Christian calendar. The thesis concludes that Papahurihia responded to the advent of Christianity in a way that was consistent with the behaviour of tohunga at the time, rather than as the founder of a syncretistic religion. It also concludes that the historiography on Papahurihia ultimately went awry because historians interpreted the missionaries’ comments about him from a secular perspective.

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  • The Whalemen of Foveaux Strait, 1829-1850

    Irwin, Cecil H (1948)

    Masters thesis
    University of Otago

    Description: iii, 187 p. [9] leaves of plates : ill., diagrs., maps. Notes: Original lacks p.160. Thesis (M. A.)--University of Otago, 1948. Microfilm. 1 reel microfilm (negative).

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  • A study of some New Zealand natural products.

    Jogia, Madhu Kant (1985)

    Doctoral thesis
    University of Otago

    xii, 348 leaves :col. ill. ; 30 cm. Includes bibliographical references. University of Otago department: Chemistry

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  • He kupu tuku iho mo tenei reanga : Te ahua o te tuku korero

    Higgins, Rawinia Ruth (1999)

    Masters thesis
    University of Otago

    170 leaves ; 30 cm. Includes bibliographical references. University of Otago department: Māori, Pacific and Indigenous Studies. "March 1999."

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  • The search for 'self' for lifestyle travellers

    Cohen, Scott Allen (2009)

    Post-doctoral thesis
    University of Otago

    Description: ix, 186 leaves : maps. ; 30 cm. Notes: "February 27th 2009". University of Otago department: Tourism. Thesis (Ph. D.)--University of Otago, 2009. Includes bibliographical references.

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  • Taxonomies of Taiwanese Aboriginal Musical Instruments

    Cheng, Lancini Jen-hao (2015)

    Doctoral thesis
    University of Otago

    This research aims to discover the indigenous taxonomy systems of Taiwanese aboriginal instruments. This is a cross-cultural investigation providing a panoramic perspective on the musical instruments of Taiwanese aborigines (Austronesians). The term ‘musical instrument’ is used in its broadest sense to refer to all sound-producing instruments in this research. There are many reasons for undertaking this research. For example, until now, few people have known what forms of aboriginal musical instruments have existed throughout the island of Taiwan, and there has been little scholarly discussion about their indigenous names and classifications. The original contribution of the research is its ethnographic fieldwork component, which results in new information concerning indigenous instruments and taxonomic schemes from the opinion of 48 cultural insiders across 17 different aboriginal groups in Taiwan. The researcher’s approach is based on participant observation - by recording the musical activity in either traditional or contemporary contexts, and by interviewing cultural insiders about their traditional music. Also, the researcher analyses the instrumental form, function and meaning of aboriginal instruments across synchronic and diachronic development. The findings in this dissertation provide a new understanding of many unknown musical instruments from different aboriginal groups (e.g. Bunun, Kavalan, Pazih-Kahabu, Puyuma, Rukai, Sakizaya, Siraya and Tsou). This investigation also makes original contributions to extend the instrument type and the numerical entry of the Hornbostel-Sachs system of musical instrument classification. Moreover, this dissertation provides a link between Taiwanese aboriginal instruments and other Austronesian musical instruments. In summary, the many factors that influence indigenous taxonomies of Taiwanese aboriginal instruments include linguistic factors (onomatopoeia, overlapped radicals, and the verbalising affix), how they are played, the materials used in their construction, their performance contexts, as well as players’ gender, social status and religion.

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  • The free child health care scheme : implications for New Zealand general practice

    Dovey, Susan May (2002)

    Doctoral thesis
    University of Otago

    xv, 260 leaves :ill. ; 30 cm. Includes bibliographical references.

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  • One Pot Double Network Hydrogels: Progress Towards Synthesis of Applicable Crosslinking Agents

    Sutherland, Peter Hugh (2015)

    Masters thesis
    University of Otago

    Our work initially looked at the possibility of being able to synthesis a double network hydrogel in just one free radical polymerisation. We intended to carefully select three compounds based on their copolymerisation reactivity under free radical conditions. This reactivity would generate a tightly cross-linked network first, followed by a loosely cross-linked network in one process. The hypothesis was tested by a Monte-Carlo simulation which showed that this two network state was achievable with known reactivity ratios. This work primarily focuses on the synthesis of novel cross-linkers based on N-vinyl pyrrolidone (1). This monomer has the necessary copolymerisation ratios with methyl methacrylate for this project, so simple difunctional analogues of 1 were designed. The synthesis and purification of these analogues proved not to be straightforward, and in the end only very small amounts of a suitable material were obtained. While the idea has merit, new ways of synthesising the key cross-linker still need to be found.

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  • The social construction of femininities in a rural New Zealand community

    Gill, Erica Jane (2007)

    Other thesis
    University of Otago

    v, 90 leaves ; 30 cm. Includes bibliographical references (leaves 85-90). "June 2007"

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  • "Square girls" : Prostitutes and prostitution in Dunedin in the 1880s

    Lucas, E Heather (1985)

    Honours Dissertation thesis
    University of Otago

    The study of prostitutes and prostitution in New Zealand has usually been subordinate to a more general analysis of women and crime. As prostitutes were, and still are, regarded as criminals in New Zealand, this has been a valid approach. However, prostitution was a particular sort of crime, in that it was essentially a crime against middle class morality. As a consequence, a study of prostitution, in itself, not only allows a fuller appreciation of the nature and extent ,of prostitution in New Zealand, but also an insight into the social structure and attitudes pertaining to sexuality and morality in colonial New Zealand. [extract from Introduction]

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  • Geophysical survey of the Paringa River valley, South Westland

    Kilner, Jeremy William (2005)

    Honours Dissertation thesis
    University of Otago

    Description: [iv], 104 leaves : ill., maps ; 30 cm. + 1 CD-ROM (4 3/4 in.) and 1 map (folded). Notes: CD-ROM and map in pockets inside back cover. University of Otago department: Geology. Thesis (B. Sc. (Hons.))--University of Otago, 2005. Includes bibliographic references.

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  • Late Quaternary geology of Glenorchy district, Upper Lake Wakatipu

    Kober, Florian (1999)

    Other thesis
    University of Otago

    vii, 127 leaves :ill., maps ; 30 cm. Includes bibliographical references. University of Otago department: Geology.

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  • The impact of patents on New Zealand's biotechnology and genetics services sectors

    Green, Aphra (2008)

    Masters thesis
    University of Otago

    x, 155 leaves ; 30 cm. Bibliography: leaves 151-155. University of Otago department: Law

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  • Haematology and inflammation in infections of farmed red deer (Cervus elaphus)

    Cross, John Philip (1991)

    Doctoral thesis
    University of Otago

    xiii, 180, i, 39 leaves, [1] folded leaf :ill. (some col.) ; 30 cm. Includes bibliographical references. University of Otago department : Microbiology

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  • W. E. Gudgeon : his contribution to the annexation of the Cook Islands.

    Currie, Ernest Rowland (1963)

    Masters thesis
    University of Otago

    v, 90 leaves ; 30 cm. Bibliography: leaf iv-v.

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  • Loving our national parks to death

    Mann, Amber (2005)

    Undergraduate thesis
    University of Otago

    iii, 91 leaves :col. ill., plan ; 30 cm. Includes bibliographical references.

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  • Customary international law in National Courts: a comparative analysis

    Bottermann, Uwe (2000)

    Masters thesis
    University of Otago

    88 leaves :maps (1 in pocket) plates ; 29 cm. Bibliography: p. 83-88. University of Otago department: Law. "October 2000"

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  • Conservation genetics of island takahe (Porphyrio mantelli)

    Lettink, Marieke (1999)

    Other thesis
    University of Otago

    ii, 66 leaves : ill. ; 30 cm. A research report submitted in partial fulfilment of the requirements for the Diploma in Wildlife Management. University of Otago department: Zoology. University of Otago Wildlife Management Report; no. 96.

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