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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.
51

Development of reference methods and reference materials for trace level antibiotic residues in food using IDMS

Muaksang, Kittiya , Chemistry, Faculty of Science, UNSW January 2009 (has links)
Food additives, drugs and growth-enhancing compounds are prominent tools in the production of sufficient quantities of affordable food. Thus, food safety has become a main concern of many countries for protection of their population's health. Analytical chemical measurements are increasingly important to ensure consumer protection, particularly in the field of antibiotic residues. International comparability and reliability of measurement results can be achieved by establishing and demonstrating the metrological traceability of those results to the International System of Units (SI). To ensure the metrological traceability of measurement results, reference methods and certified reference materials (CRMs) are needed. Nitrofuran antibiotic drugs used for the treatment of bacterial and protozoan infections in animals were studied in this thesis. A high accuracy reference method and an appropriate CRM for the detection of nitrofurans in prawns have been developed. A reference method for the measurement of mass fractions of nitrofuran metabolites 3-amino-5-methyl-morpholino-2-oxazolidinone (AMOZ), 3-amino-2-oxazolidinone (AOZ), semicarbazide (SEM) and 1-aminohydantoin (AHD) has been developed utilising an exact matching double isotope dilution mass spectrometry (IDMS) method. A feasibility study on a fortified reference material was carried out by preparing fortified samples containing the four nitrofuran metabolites. The stability testing results showed that the analytes in the freeze-dried matrix were more stable than in the wet form. Freeze-dried certified reference materials of nitrofurans in prawns have been produced; an incurred AOZ (CRM_P1) and incurred AOZ and fortified SEM (CRM_P2). The reference method developed was applied for the characterisation of certified reference materials for homogeneity, stability study and certification. The prepared certified reference materials were found to be homogeneous and remained stable under normal transport conditions. The measurement uncertainty of the measurement results obtained by the reference method developed was determined by thoroughly examining all possible sources of potential bias and precision effects. An initial measurement uncertainty for certified values of AOZ in both materials has also been estimated. Metrological traceability of measurement results obtained by the developed reference method and the reference value of the prepared certified reference materials has been established through the use of the traceable primary ratio method of exact matching double IDMS, the use of certified nitrofuran metabolite standards, and gravimetric preparation of samples.
52

Legislative reference work

Leek, John Halvor January 1925 (has links)
University of Pennsylvania, Thesis (Ph.D.) / "Bibliography": p. 165-172. - RLIN, CTRG98-B3105. - Reproduction of original from Yale Law School Library
53

New learning models for robust reference resolution

Denis, Pascal, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
54

The relationship of junior college faculty reference group attitudes toward the mutipurpose functions of the junior college.

Tolley, Charles Howard. January 1969 (has links)
Thesis (Ed.D.) --University of Tulsa, 1969. / Bibliography: leaves 61-63.
55

L'image cubiste et la question de l'autoréférence

Beauchemin, Anne, January 1900 (has links)
Thesis (Ph.D.). / Written for the Dept. of Art History and Communication Studies. Title from title page of PDF (viewed 2008/01/12). Includes bibliographical references.
56

Legislative reference work a comparative study /

Leek, John H. January 1925 (has links)
Thesis (Ph.D.)--University of Pennsylvania. / Reproduction of original from Yale Law School Library. "Bibliography": p. 165-172.
57

Legislative reference work a comparative study ...

Leek, John Halvor. January 1925 (has links)
Thesis (Ph. D.)--University of Pennsylvania, 1925. / Bibliography: p. 165-172.
58

The development of reference services in American research libraries

Rothstein, Samuel, January 1954 (has links)
Thesis (Ph. D.)--University of Illinois. / Bibliography: l. 261-279.
59

Catholic reference sources: a critical study.

McCabe, James Patrick. January 1968 (has links)
Thesis--University of Michigan. / Photocopy of typescript. Ann Arbor, Mich., University Microfilms, 1974. 21 cm. Bibliography: leaves 353-355.
60

The effectiveness of information service in medium size public libraries

Crowley, Terence, January 1968 (has links)
Thesis - Rutgers, the State University. / Reproduced by University Microfilms, inc. Bibliography: leaves 65-67.

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