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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.
591

Analysis of Trace Amounts of Adulterants Found in Powders/Supplements Utilizing Direct Inject, Nanomanipulation, and Mass Spectrometry

Nnaji, Chinyere 08 1900 (has links)
The regulations of many food products in the United States have been made and followed very well but unfortunately some products are not put under such rigorous standards as others. This leads to products being sold, that are thought to be healthy, but in reality contain unknown ingredients that may be hazardous to the consumers. With the use of several instrumentations and techniques the detection, characterization and identification of these unknown contaminates can be determined. Both the AZ-100 and the TE2000 inverted microscope were used for visual characterizations, image collection and to help guide the extraction. Direct analyte-probed nanoextraction (DAPNe) technique and nanospray ionization mass spectrometry (NSI-MS) was the technique used for examination and identification of all adulterants. A Raman imaging technique was than introduced and has proven to be a rapid, non-destructive and distinctive way to localize a specific adulterant. By compiling these techniques then applying them to the FDA supplied test samples three major adulterants were detected and identified.
592

Disease Tissue Imaging and Single Cell Analysis with Mass Spectrometry

Hamilton, Jason S. 05 1900 (has links)
Cells have been found to have an inherent heterogeneity that has led to an increase in the development of single-cell analysis methods to characterize the extent of heterogeneity that can be found in seemingly identical cells. With an understanding of normal cellular variability, the identification of disease induced cellular changes, known as biomarkers, may become more apparent and readily detectable. Biomarker discovery in single-cells is challenging and needs to focus on molecules that are abundant in cells. Lipids are widely abundant in cells and play active roles in cellular signaling, energy metabolism, and are the main component of cellular membranes. The regulation of lipid metabolism is often disrupted or lost during disease progression, especially in cancer, making them ideal candidates as biomarkers. Challenges exist in the analysis of lipids beyond those of single-cell analysis. Lipid extraction solvents must be compatible with the lipid or lipids of interest. Many lipids are isobaric making mass spectrometry analysis difficult without separations. Single-cell extractions using nanomanipulation coupled to mass spectrometry has shown to be an excellent method for lipid analysis of tissues and cell cultures. Extraction solvents are tunable for specific lipid classes, nanomanipulation prevents damage to neighboring cells, and lipid separations are possible through phase dispersion. The most important aspect of single-cell analysis is that it uncovers the extent of cellular heterogeneity that exists among cellular populations that remains undetected during averaged sampling.
593

Multivariate Pattern Recognition of Petroleum-Based Accelerants and Fuels

Bodle, Eric S. 02 October 2007 (has links)
No description available.
594

Multidimensional NMR studies of poly(ethylene-<i>co</i>-1-octene) copolymers and poly(ethylene-<i>co</i>-vinyl acetate-<i>co</i>-carbon monoxide) terpolymers

Nuamthanom, Anuttra 02 October 2007 (has links)
No description available.
595

PROTEIN CROSSLINKING BY THE MAILLARD REACTION WITH ASCORBIC ACID AND GLUCOSE

DAI, ZHENYU 13 July 2007 (has links)
No description available.
596

Characterizatin of a Type II Metallothionein from <i>Helianthus annuus</i> Using Recombinant DNA Techniques

Bhogavalli, Sridhar January 2007 (has links)
No description available.
597

Analytical Preconcentration Systems Based on Nanostructured Materials

Kijak, Anna M. 09 April 2003 (has links)
No description available.
598

ADAPTATION OF ATTENUATED TOTAL INTERNAL REFLECTANCE INFRARED MICROSPECTROSCOPY TO FLOW INJECTION AND SEPARATION TECHNIQUES

Patterson, Brian Martin 20 April 2004 (has links)
No description available.
599

INFRARED MICROSPECTROSCOPIC TECHNIQUES FOR THE QUALITATIVE ANALYSIS OF CROSS-SECTIONED RENAL CALCULI AND EMBEDDED MINERALIZED DEPOSITS

Anderson, Jennifer C. 30 April 2004 (has links)
No description available.
600

Techniques for the Detection and Development of: Part I Detection of Ozone for Water Treatment Part II. Utilizing Layer-By-Layer Thin Films with Long Period Grating Fibers

Puckett, Sean D. 28 April 2006 (has links)
No description available.

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