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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.
71

Methods and algorithms for quantitative analysis of metallomic images to assess traumatic brain injury

Gaudreau-Balderrama, Amanda 10 July 2017 (has links)
The primary aim of this thesis is to develop image processing algorithms to quantitatively determine the link between traumatic brain injury (TBI) severity and chronic traumatic encephalopathy (CTE) neuropathology, specifically looking into the role of blood-brain barrier disruption following TBI. In order to causally investigate the relationship between the tau protein neurodegenerative disease CTE and TBI, mouse models of blast neurotrauma (BNT) and impact neurotrauma (INT) are investigated. First, a high-speed video tracking algorithm is developed based on K-means clustering, active contours and Kalman filtering to comparatively study the head kinematics in blast and impact experiments. Then, to compare BNT and INT neuropathology, methods for quantitative analysis of macroscopic optical images and fluorescent images are described. The secondary aim of this thesis focuses on developing methods for a novel application of metallomic imaging mass spectrometry (MIMS) to biological tissue. Unlike traditional modalities used to assess neuropathology, that suffer from limited sensitivity and analytical capacity, MIMS uses a mass spectrometer -- an analytical instrument for measuring elements and isotopes with high dynamic range, sensitivity and specificity -- as the imaging sensor to generate spatial maps with spectral (vector-valued) data per pixel. Given the vector nature of MIMS data, a unique end-to-end processing pipeline is designed to support data acquisition, visualization and interpretation. A novel multi-modal and multi-channel image registration (MMMCIR) method using multi-variate mutual information as a similarity metric is developed in order to establish correspondence between two images of arbitrary modality. The MMMCIR method is then used to automatically segment MIMS images of the mouse brain and systematically evaluate the levels of relevant elements and isotopes after experimental closed-head impact injury on the impact side (ipsilateral) and opposing side (contralateral) of the brain. This method quantifiably confirms observed differences in gadolinium levels for a cohort of images. Finally, MIMS images of human lacrimal sac biopsy samples are used for preliminary clinicopathological assessments, supporting the utility of the unique insights MIMS provides by correlating areas of inflammation to areas of elevated toxic metals. The image processing methods developed in this work demonstrate the significant capabilities of MIMS and its role in enhancing our understanding of the underlying pathological mechanisms of TBI and other medical conditions. / 2019-07-09T00:00:00Z
72

The determination of molybdenum in seawater by ICP-AES after preconcentration by diethylenetriaminetetraacetic acid-functionalized polysiloxane.

January 2002 (has links)
Chan Sze-Man. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (leaves 65-73). / Abstracts in English and Chinese. / Acknowledgment --- p.i / Table of Contents --- p.ii / Abstract --- p.v / Abstract (Chinese Version) --- p.vi / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Molybdenum in the Environment --- p.1 / Chapter 1.1.1 --- General Chemistry of Molybdenum --- p.1 / Chapter 1.1.2 --- Molybdenum in Animals and Plants --- p.1 / Chapter 1.1.3 --- Uses of Molybdenum Compounds --- p.3 / Chapter 1.2 --- Inductively Coupled Plasma Atomic Emission Spectrometry --- p.4 / Chapter 1.2.1 --- Principle of ICP-AES --- p.4 / Chapter 1.2.2 --- Inductively Coupled Plasma Emission Source --- p.5 / Chapter 1.2.3 --- Optical System --- p.6 / Chapter 1.2.4 --- Advantages of ICP-AES --- p.7 / Chapter 1.2.5 --- Disadvantages of ICP-AES --- p.8 / Chapter 1.3 --- Preconcentration Method --- p.9 / Chapter 1.4 --- Polysiloxane --- p.11 / Chapter 1.4.1 --- Introduction of Silica-gel --- p.11 / Chapter 1.4.2 --- Introduction of Sol-gel Processes --- p.13 / Chapter 1.4.3 --- Hybrid Inorganic-organic Sol-gel Materials --- p.14 / Chapter 1.4.4 --- Advantages Using Sol-gel Preparation of Organomodified Silica --- p.16 / Chapter 1.5 --- Chelating Resin --- p.19 / Chapter 1.6 --- Scope of Work --- p.21 / Chapter Chapter 2 --- Experimental --- p.22 / Chapter 2.1 --- Apparatus and Instrument --- p.22 / Chapter 2.2 --- Chemicals --- p.24 / Chapter 2.3 --- Samples --- p.25 / Chapter 2.4 --- Procedures --- p.26 / Chapter 2.4.1 --- Preparation of Diethylenetriaminetetraacetic-acid Functionalized Polysiloxane --- p.26 / Chapter 2.4.1.1 --- Preparation of Silica Precursor --- p.26 / Chapter 2.4.1.2 --- Functionalization with Diethylenetriamine --- p.27 / Chapter 2.4.1.3 --- Carboxymethylation of the amine groups of the Polysiloxane --- p.28 / Chapter 2.4.2 --- Preconcentration and Determination of Molybdenum --- p.29 / Chapter 2.4.2.1 --- Optimum pH for Adsorption --- p.29 / Chapter 2.4.2.2 --- Amount of Polysiloxane Required for Sorption of Trace Amount of Molybdenum --- p.29 / Chapter 2.4.2.3 --- Equilibrium Time --- p.30 / Chapter 2.4.2.4 --- Total Adsorption Capacity --- p.30 / Chapter 2.4.2.5 --- Adsorption Isotherm of Molybdenum --- p.30 / Chapter 2.4.2.6 --- Desorption Studies --- p.31 / Chapter 2.4.2.7 --- Effect of Foreign Ions on Preconcentration --- p.31 / Chapter 2.4.2.8 --- Preparation of the Mini-column --- p.32 / Chapter 2.4.2.9 --- Effect of Flow Rate --- p.33 / Chapter 2.4.2.10 --- Reusability of the Mini-column --- p.33 / Chapter 2.4.2.11 --- Preconcentration Factor and Detection Limit --- p.33 / Chapter 2.4.2.12 --- Determination of Mo(VI) in Seawater by ICP-AES --- p.33 / Chapter Chapter 3 --- Results and Discussion --- p.35 / Chapter 3.1 --- Characterization of Diethylenetriaminetetraacetic-acid Functionalized Polysiloxane --- p.35 / Chapter 3.2 --- pH Dependence of Mo(VI) Ion Uptake --- p.44 / Chapter 3.3 --- Amount of Polysiloxane Required for Adsorption of Trace Amount of Mo(VI) --- p.45 / Chapter 3.4 --- Equilibrium Time --- p.46 / Chapter 3.5 --- Total Adsorption Capacity --- p.47 / Chapter 3.6 --- Adsorption Isotherm of Molybdenum --- p.48 / Chapter 3.7 --- Desorption Studies --- p.54 / Chapter 3.8 --- Effect of Foreign Ions on Preconcentration --- p.55 / Chapter 3.9 --- Effect of Flow Rate on the Recovery of Mo(VI) --- p.57 / Chapter 3.10 --- Reusability of the Column --- p.58 / Chapter 3.11 --- Preconcentration Factor --- p.59 / Chapter 3.12 --- Detection Limit --- p.59 / Chapter 3.13 --- Accuracy --- p.60 / Chapter 3.14 --- Determination of Mo(VI) in Seawater Samples --- p.61 / Chapter 3.15 --- Precision --- p.62 / Chapter Chapter 4 --- Conclusion --- p.63 / Chapter Chapter 5 --- References --- p.65
73

Trace element content variation within sulfides of the Fäboliden gold deposit

Lydia, Somers January 2019 (has links)
The Fäboliden gold deposit is an ore body in northern Sweden’s Bothnian Basin and has been the subject of studies and test mining since the early 2000s when the Gold Line, an area of anomalously high-Au glacial till in Northern Sweden, became a center of economic interest. The deposit is a hypozonal orogenic gold deposit that displays many characteristic features of ore bodies of this type, including the presence of compound sulfide grains composed of a core of löllingite surrounded by a rim of arsenopyrite, and an abundance of pyrrhotite throughout the deposit and surrounding alteration zone. Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to first map the distribution of trace elements in several of the arsenpyrite-löllingite grains, then to perform spot analyses of pyrrhotite grains in samples from across the distal and proximal alteration zones of the deposit. The maps of the trace elements in the compound löllingite-arsenopyrite grains show that: As and Au are found in greater abundance in the löllingite than in the arsenopyrite; Cu, Fe, S, and Ti are found in greater abundance in the arsenopyrite than in the löllingite; and Ag, Au, Bi, La, Mn, Pb, Sr, Ti and Tl are found in zones of secondary enrichment along fractures within the grains. Uranium and V may also be enriched along fractures, although this isn’t clear on all of the maps. Gold is an element of particular interest, because its distribution throughout the sulfide phases can be used to constrain the mechanism and relative timing of mineralization within the deposit. The presence of invisible gold within the löllingite, but not within the arsenopyrite, shows that gold is not incorporated into arsenopyrite at high temperatures and will instead be concentrated in the löllingite core of the composite grain and at the margin between the two sulfide phases as the löllingite is altered to arsenopyrite. Previous research on the Fäboliden gold deposit, including geothermometric analysis of vein-hosted graphite within fluid inclusions and garnet-biotite geothermometry as well as structural evidence provided by regional deformation, indicate that mineralization occurred post-peak metamorphism. The textures seen are therefore not conclusive of mineralization occurring syn- or pre-peak metamorphism, as has previously been proposed based on research of orogenic gold deposits in Western Australia. The spot analysis of pyrrhotite samples from across the deposit shows a distinct decrease in Ni and Co content in the proximal alteration zone, suggesting uptake of these elements by other minerals such as the löllingite and arsenopyrite. Multiple analyses performed on single grains show local variation, but are insufficient to establish the presence or determine the character of growth zonation within pyrrhotite.
74

none

Chu, Yun-Ling 20 July 2010 (has links)
none
75

Determination of Ca and P in foods and B, Si, P and S in steels by dynamic reaction cell inductively coupled plasma mass spectrometry

Yang, Chiao-Hui 12 July 2004 (has links)
Determination of Ca and P in foods and B, Si, P and S in steels by dynamic reaction cell inductively coupled plasma mass spectrometry
76

Determination of Ga,Ge,As,Se and Sb in coal fly ash and S and Pb in gasoline by inductively coupled plasma mass spectrometry

Ni, Jun-Long 12 July 2004 (has links)
Ga,Ge,As,Se and Sb in coal fly ash S and Pb in gasoline
77

none

Lin, Liang-Yen 30 July 2008 (has links)
none
78

Measurement and Antenna Design of RFID Tags for Metallic Objects

Chen, Sung-lin 07 January 2010 (has links)
A measurement method for characterizing RFID chip has been proposed that can measure the approximate Read/Write threshold power and impedance of RFID strap with minimum operating procedures; furthermore, the complicated RF facilities are not required. Obtaining the specifications of RFID strap allows designers to estimate maximum read range of designed RFID tag in advance. Therefore, the implemented cost and design cycle times can be reduced substantially. For the verification of the final match condition of assembled RFID tag, a direct measurement technique has been developed, which not only can verify the final impedance match condition of the assembled RFID tags, but can also be used to identify the resistance and reactance mismatch condition between the RFID chip and antenna. The measurement data obtained from the verification method can also be used to estimate the assembly error introduced by different mounting methods. The use of the corrected circuit model of the RFID chip impedance, which includes the assembly error, helps improve the accuracy of the RFID tag design. In the RFID metal tag design, a series of low profile and miniature RFID tags, which is directly attached on metallic objects, has been developed. A series of low cost and easily produced RFID tag antenna structures also has been realized for RFID application on hanging metallic tag, which makes the RFID solution well suited for metallic tag of labeling system that requires integration of RFID technology. The attached RFID metal tag and the metallic RFID hanging tag cover most of the RFID application on steel products in the steel industry.
79

Applicability of laser ablation and partial dissolution ICP-MS techniques on Mn-Fe-oxide coatings of stream pebbles to mineral exploration and environmental monitoring /

Coish, Diane Wanda, January 2000 (has links)
Thesis (M.Sc.)--Memorial University of Newfoundland, 2001. / Bibliography: leaves 109-115. Also available online.
80

Determination of trace elements levels in plasma from larvae in the course of baculoviral and bacterial infections by inductively coupled plasma-mass spectrometry (ICP-MS)

Sun, Rui. Robertson, J. David January 2009 (has links)
Title from PDF of title page (University of Missouri--Columbia, viewed on Feb 19, 2010). The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file. Thesis advisor: Dr. John D. Robertson. Includes bibliographical references.

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