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1
Chan, Chun-yu. "Mass spectrometric analysis of selected glycoproteins." Thesis, Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B3147942X.
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Daigle, J. A. Bernard. "Development of an ion trap mass spectrometer for elemental analysis." Thesis, University of British Columbia, 1990. http://hdl.handle.net/2429/30688.
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Mass spectrometry is a widely used technique for the performance of elemental analysis: not only does it provides excellent limits of detection for a large number of elements, but it is also able to provide information about the isotopic distribution of the analyte. The radio-frequency quadrupole ion trap is a relatively new design of mass spectrometer, which offers the ability to confine charged particles for extended periods of time in a well defined volume by applying a radio-frequency oscillating voltage to an arrangement of three electrodes. A mass analysis of the trapped ions can be obtained by selectively extracting the ions from the cavity of the trap, where they can be detected by an electron multiplier. Despite its unique capabilities, to date the applications of the ion trap mass spectrometer have mostly been restricted to gas chromatography detection. Until recently, there have been very few attempts to use it for any other types of routine analysis.
Our interest lies in the development of an instrument capable of performing a complete mass spectrometric elemental analysis of small volume liquid samples (a few (μL) at trace or ultra-trace concentration levels. The ability of the ion trap to accumulate ions in its cavity and to provide an entire mass spectrum of these ions in a single scan of the radio-frequency oscillating voltage applied between the electrodes, makes it a very interesting candidate for the ultra-trace analysis of small size samples. However, to perform an analysis on a sample with the ion trap the sample must first be vaporized; and if an elemental analysis is required, the sample will also have to be atomized. The graphite furnace atomizer used in atomic absorption spectroscopy offers a number of advantages which make it potentially useful for this purpose: it has a high transport efficiency of the analyte from liquid or solid state to the vapour phase, the ionization of the analyte in the furnace is very low (as required by the ion trap) and it handles small volume samples very well. A graphite furnace ion
trap mass spectrometer was designed to fulfil the need of having instrumentation capable of multielemental mass spectrometric analysis of small volume samples containing traces of the analytes of interest.
This document contains a description of the principles of operation of the ion trap as well as a detailed description of the instrument actually built. Data are presented in order to assess the capabilities of the instrument, as well as some of the problems encountered with it. The results obtained with the graphite furnace ion trap mass spectrometer allow us to conclude that the proposed design is not appropriate for the performance of elemental analysis, but is appropriate for mass spectrometric study of low boiling point compounds which can interfere with atomic absorption analysis: it is calculated that these compounds could be analysed at the ppm level.
Promising results obtained with a set up in which the analyte is vaporized directly into the cavity of the ion trap through laser ablation are also presented. These limited results show the potential of this methodology for direct elemental analysis of solid samples.<br>Science, Faculty of<br>Chemistry, Department of<br>Graduate
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Nelson, Paul Redfield. "Applications of analytical collisional mass spectrometry." Diss., Georgia Institute of Technology, 1987. http://hdl.handle.net/1853/27053.
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Wentzel, Mauritz. "Identification and characterization of novel oncology related platinum complexes using chromatographic and mass spectrometric techniques." Thesis, Nelson Mandela Metropolitan University, 2008. http://hdl.handle.net/10948/715.
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In this thesis mass spectral and chromatographic techniques were developed and applied to identify and characterise numerous novel platinum(II) and (IV) compounds designed as anticancer agents. In a novel method for the synthesis of cis-oxalato(trans- -1,2- cyclohexanediamine)platinum(II) or oxaliplatin these techniques could be applied to differentiate between the molecular complex and the autoionised analogue (viz. Ptdach2 2+Ptox2 2-). In another novel synthetic method for the same compound the ligand exchange reactions at various temperatures could be investigated and kinetic curves obtained served to illuminate the chemistry involved, indicating the role of small amounts of water in the essentially non-aqueous solvent systems dmf and isoamyl alcohol respectively. These allowed ligand exchange without resulting in hydrolyses even up to 85°C. The ionisation rate of divalent platinum halide complexes was determined for various amine ligands as well as N-S chelate ligands. A comparison of these could suggest why N-S complexes have poor anticancer action. Ionisation was not only studied for neutral molecular species but also for monocationic ones. Relationships could be found with stereochemical aspects of the chelates used. By investigating results of EV-CAD studies thermodynamic data could be obtained which indicated that bond strength decreases from chloro to iodo analogues although extent of ionisation in aqueous solution, i.e kinetic stability, is the reverse. Products formed by the reaction of NO2 gas with Platinum(II) compounds could be identified and separated which greatly contributed to the understanding of the chemistry involved in the formation of mononitro platinum(IV) complexes. Some of these proved to have exceptional anticancer properties. Studies of the interaction of thiol containing biomolecules were performed as a function of time. The results contributed to the understanding of the action of the anticancer agents.
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Wang, Yunli. "Mass Spectrum Analysis of a Substance Sample Placed into Liquid Solution." Thesis, North Dakota State University, 2011. https://hdl.handle.net/10365/28881.
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Mass spectrometry is an analytical technique commonly used for determining elemental composition in a substance sample. For this purpose, the sample is placed into some liquid solution called liquid matrix. Unfortunately, the spectrum of the sample is not observable separate from that of the solution. Thus, it is desired to distinguish the sample spectrum. The analysis is usually based on the comparison of the mixed spectrum with the one of the sole solution. Introducing the missing information about the origin of observed spectrum peaks, the author obtains a classic set up for the Expectation-Maximization (EM) algorithm. The author proposed a mixture modeling the spectrum of the liquid solution as well as that of the sample. A bell-shaped probability mass function obtained by discretization of the univariate Gaussian probability density function was proposed or serving as a mixture component. The E- and M- steps were derived under the proposed model. The corresponding R program is written and tested on a small but challenging simulation example. Varying the number of mixture components for the liquid matrix and sample, the author found the correct model according to Bayesian Information Criterion. The initialization of the EM algorithm is a difficult standalone problem that was successfully resolved for this case. The author presents the findings and provides results from the simulation example as well as corresponding illustrations supporting the conclusions.
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Carlson, Richard Earl. "Structural and mechanistic studies by modern mass spectrometry." Diss., Georgia Institute of Technology, 1996. http://hdl.handle.net/1853/27856.
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Peppe, Salvatore. "Some unusual, astronomically significant organic molecules." Title page, contents and abstract only, 2002. http://web4.library.adelaide.edu.au/theses/09PH/09php4241.pdf.
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Appendix inside back cover. "June 2002" Bibliography: leaves 157-168. Experimental and theoretical studies were carried out on a number of unusual organic molecules of potential astronomical significance. The experimental work was corroborated by various theoretical approaches and by utilising computer-based quantum chemical calculations. Various covalently bound, anionic and neutral oxocarbon species were formed and studied. Additionally, two analogous heterocumulenic systems were investigated. Some isomers of either system, when energised, were shown to undergo gas-phase rearrangement processes.
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Sihlbom, Carina. "Mass spectrometry for comparative proteomics of degenerative and regenerative processes in the brain /." Göteborg : Institute of Biomedicine, Sahlgrenska Academy, Göteborg University, 2006. http://hdl.handle.net/2077/774.
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Andersson, Kjell. "Development of a method for comparing amphetamine samples /." Linköping : Univ, 2004. http://www.bibl.liu.se/liupubl/disp/disp2004/tek879s.pdf.
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Russell, Steven Arthur. "Machine learning and in silico modeling for improved identification of peptides from shotgun proteomic Ms/Ms spectra /." Connect to full text via ProQuest. IP filtered, 2005.
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Thesis (Ph.D. in Bioinformatics) -- University of Colorado, 2005.<br>Typescript. Includes bibliographical references (leaves 116-124). Free to UCDHSC affiliates. Online version available via ProQuest Digital Dissertations;
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Melles, Ermias. "C-peptide structural and functional relationships studied by biosensor technology and mass spectrometry /." Stockholm, 2005. http://diss.kib.ki.se/2005/91-7140-343-4/.
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Hirschberg, Daniel. "Sample preparation and mass spectrometry in proteome studies /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-934-x/.
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Norberg, Åke. "Isolation and characterization of regulatory peptides and bioactive compounds /." Stockholm : Karolinska institutet, 2004. http://diss.kib.ki.se/2004/91-7349-882-3/.
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Eriste, Elo. "Purification, structure and function of bioactive peptides /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-853-X/.
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Sanchez, Washington Hugo. "Cataract affected infant lens tissue and protein specific mapping of intact tissue analysis by MALDI-TOF/MS." Thesis, Queensland University of Technology, 2002.
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O'Hair, Richard Alfred John. "Studies in gas phase ion chemistry : a thesis presented for the degree of Doctor of Science in the Faculty of Science of the University of Adelaide /." Title page, table of contents and summary only, 2004. http://web4.library.adelaide.edu.au/theses/09SD/09sdo362.pdf.
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Bartee, Eric Carter. "Discovery and characterization of a novel family of human ubiquitin ligases termed Membrane Associated RING-CH (MARCH) proteins." Oregon Health & Science University, 2007. http://content.ohsu.edu/u?/etd,629.
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Ph.D.<br>Molecular Microbiology and Immunology<br>Both poxviruses and γ2-herpesviruses share the K3-family of viral immune evasion proteins. These proteins are characterized by an amino-terminal RING-CH domain followed by two transmembrane domains. We analyzed several human homologues of the K3-family termed membrane-associated RING-CH (MARCH) proteins. All MARCH proteins localized to subcellular membranes while several reduced surface levels of known K3-family substrates. Thus, MARCH proteins appear to be structurally and functionally homologous to viral K3 proteins. One of the major challenges in determining the function of this family is the identification of their physiological substrates. To overcome this we created a quantitative proteomics approach which can be used to identify novel substrates for both the K3- and MARCH-families. Using stable isotope labeling by amino acids in cell culture, we compared the proteome of plasma membrane, golgi, and endoplasmic reticulum membranes in the presence and absence of K5 and MARCH-VIII. Quantitative mass spectrometric protein identification from these fractions revealed that CD316 (bone marrow stromal antigen 2), CD166 (activated leukocyte cell adhesion molecule) and syntaxin-4 were consistently underrepresented in the plasma membrane of K5 expressing cells, while CD44, CD81 (TAPA-1) and B-cell receptor-associated protein 31kDa (Bap31) were consistently underrepresented in the plasma membrane of MARCH-VIII expressing cells. Furthermore, downregulation of each of these proteins was independently confirmed. Our results both identify and characterize a novel family of human ubiquitin ligase enzymes and elucidate a novel technique which can analyze this family and be easily adapted to the analysis of other cellular enzymes viral immune modulators.
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Bodin, Karl. "On the role of cytochrome P450 3A4 in the metabolism of cholesterol and bile acids /." Stockholm, 2004. http://diss.kib.ki.se/2004/91-7349-769-X/.
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Öhman, Daniel. "Bioanalytical development for application in therapeutic drug monitoring : focus on drugs used in psychiatry /." Linköping : Univ, 2003. http://www.bibl.liu.se/liupubl/disp/disp2003/med775s.pdf.
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Losik, Len. "Adapting Fourier Analysis for Predicting Earth, Mars and Lunar Orbiting Satellite's Telemetry Behavior." International Foundation for Telemetering, 2011. http://hdl.handle.net/10150/595773.
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ITC/USA 2011 Conference Proceedings / The Forty-Seventh Annual International Telemetering Conference and Technical Exhibition / October 24-27, 2011 / Bally's Las Vegas, Las Vegas, Nevada<br>Prognostic technology uses a series of algorithms, combined forms a prognostic-based inference engine (PBIE) for the identification of deterministic behavior embedded in completely normal appearing telemetry from fully functional equipment. The algorithms used to define normal behavior in the PBIE from which deterministic behavior is identified can be adapted to quantify normal spacecraft telemetry behavior while in orbit about a moon or planet or during interplanetary travel. Time-series analog engineering data (telemetry) from orbiting satellites and interplanetary spacecraft are defined by harmonic and non-harmonic influences, which shape it behavior. Spectrum analysis can be used to understand and quantify the fundamental behavior of spacecraft analog telemetry and relate the behavior's frequency and phase to its time-series behavior through Fourier analysis.
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Losik, Len. "Adapting Fourier Analysis for Predicting Earth, Mars and Lunar Orbiting Satellite's Telemetry Behavior." International Foundation for Telemetering, 2010. http://hdl.handle.net/10150/604279.
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ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California<br>Prognostic technology uses a series of algorithms, combined forms a prognostic-based inference engine (PBIE) for the identification of deterministic behavior embedded in completely normal appearing telemetry from fully functional equipment. The algorithms used to define normal behavior in the PBIE from which deterministic behavior is identified can be adapted to quantify normal spacecraft telemetry behavior while in orbit about a moon or planet or during interplanetary travel. Time-series analog engineering data (telemetry) from orbiting satellites and interplanetary spacecraft are defined by harmonic and non-harmonic influences, which shape it behavior. Spectrum analysis can be used to understand and quantify the fundamental behavior of spacecraft analog telemetry and relate the behavior's frequency and phase to its time-series behavior through Fourier analysis.
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Goodman, Roy Parish. "Apolipoprotein C1 : expression, characterisation and mass spectral analysis /." [St. Lucia, Qld.], 2004. http://www.library.uq.edu.au/pdfserve.php?image=thesisabs/absthe18361.pdf.
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Fournié, Jean-Jacques. "Etude structurale et serologique du mycoside a produit par mycobacterium kansasii." Toulouse 3, 1986. http://www.theses.fr/1986TOU30191.
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Xia, Yang. "Chromatography coupled with mass spectrometry in bioanalysis." Diss., Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/27998.
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Janošková, Lenka. "Dynamická analýza konstrukce zatížené seismickým zatížením." Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2013. http://www.nusl.cz/ntk/nusl-226464.
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In this diploma thesis the seismic load on two different models is solved – the first model is a beam hall and the second model is a multistory building. The calculation of seismic load was performed according to standard ČSN EN 1998-1 (Eurocode 8) using the response spectrum analysis and the method of equivalent static forces (substi-tute load). For the combination of seismic responses in different directions are used SRSS and CQC rules. Models and calculations were solved in a student’s version of program RFEM 4.10 (Ing. Software Dlubal, s.r.o.). The comparison of mentioned methods in each models, also the comparison of combinative rules in calculation and the final evaluation of seismic responses on both of models are the subject of this thesis.
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Schlaffner, Christoph Norbert. "Proteogenomics for personalised molecular profiling." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/275137.
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Technological advancements in mass spectrometry allowing quantification of almost complete proteomes make proteomics a key platform for generating unique functional molecular data. Furthermore, the integrative analysis of genomic and proteomic data, termed proteogenomics, has emerged as a new field revealing insights into gene expression regulation, cell signalling, and disease processes. However, the lack of software tools for high-throughput integration and unbiased modification and variant detection hinder efforts for large-scale proteogenomics studies. The main objectives of this work are to address these issues by developing and applying new software tools and data analysis methods. Firstly, I address mapping of peptide sequences to reference genomes. I introduce a novel tool for high-throughput mapping and highlight its unique features facilitating quantitative and post-translational modification mapping alongside accounting for amino acid substitutions. The performance is benchmarked. Furthermore, I offer an additional tool that permits generation of web accessible hubs of genome wide mappings. To enable unbiased identification of post-translational modifications and amino acid substitutions for high resolution mass spectrometry data, I present algorithmic updates the mass tolerant blind spectrum comparison tool ’MS SMiV’. I demonstrate the applicability of the changes by benchmarking against a published mass tolerant database search of a high resolution tandem mass spectrometry dataset. I then present the application of ‘MS SMiV’ on a panel of 50 colorectal cancer cell lines. I show that the adaption of ‘MS SMiV’ outperforms traditional sequence database based identification of single amino acid variants. Furthermore, I highlight the utility of mass tolerant spectrum matching in combination with isobaric labelled quantitative proteomics in distinguishing between post-translational modifications and amino acid variants of similar mass. In the last part of this work I integrate both tools with a high-throughput proteogenomic identification pipeline and apply it to a pilot study of chondrocytes derived from 12 osteoarthritic individuals. I show the value of this approach in identifying variation between individuals and molecular levels and highlight them with individual examples. I show that multi-plexed proteogenomics can be used to infer genotypes of individuals.
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White, Katie Margaret. "Statistical analysis of visible absorption spectra and mass spectra obtained from dyed textile fibers." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4646.
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The National Academy of Sciences recently published a report which calls for improvements to the field of forensic science. Their report criticized many forensic disciplines for failure to establish rigorously-tested methods of comparison, and encouraged more research in these areas to establish limitations and assess error rates. This study applies chemometric and statistical methods to current and developing analytical techniques in fiber analysis. In addition to analysis of commercially available dyed textile fibers, two pairs of dyes are selected for custom fabric dyeing based on the similarities of their absorbance spectra and dye molecular structures. Visible absorption spectra for all fiber samples are collected using microspectrophotometry (MSP) and mass spectra are collected using electrospray ionization (ESI) mass spectrometry. Statistical calculations are performed using commercial software packages and software written in-house. Levels of Type I and Type II error are examined for fiber discrimination based on hypothesis testing of visible absorbance spectra profiles using a nonparametric permutation method. This work also explores evaluation of known and questioned fiber populations based on an assessment of statistical p-value distributions from questioned-known fiber comparisons with those of known fiber self-comparisons. Results from the hypothesis testing are compared with principal components analysis (PCA) and discriminant analysis (DA) of visible absorption spectra, as well as PCA and DA of ESI mass spectra. The sensitivity of a statistical approach will also be discussed in terms of how instrumental parameters and sampling methods may influence error rates.<br>ID: 030423335; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.S.)--University of Central Florida, 2010.; Includes bibliographical references (p. 112-119).<br>M.S.<br>Masters<br>Department of Chemistry<br>Sciences
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Szpylka, John. "Mass spectral analysis of electrochemical reactants: studies of decarboxylation reactions /." The Ohio State University, 1991. http://rave.ohiolink.edu/etdc/view?acc_num=osu148775772399743.
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Shen, Lingli. "Spatial mass spectral data analysis using factor and correlation models." Thesis, University of Sheffield, 2015. http://etheses.whiterose.ac.uk/9506/.
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ToF-SIMS is a powerful and information rich tool with high resolution and sensitivity compared to conventional mass spectrometers. Recently, its application has been extended to metabolic profiling analysis. However, there are only a few algorithms currently available to handle such output data from metabolite samples. Therefore some novel and innovative algorithms are undoubtedly in need to provide new insights into the application of ToF-SIMS for metabolic profiling analysis. In this thesis, we develop novel multivariate analysis techniques that can be used in processing ToF-SIMS data extracted from metabolite samples. Firstly, several traditional multivariate analysis methodologies that have previously been suggested for ToF-SIMS data analysis are discussed, including Clustering, Principal Components Analysis (PCA), Maximum Autocorrelation Factor (MAF), and Multivariate Curve Resolution (MCR). In particular, PCA is selected as an example to show the performance of traditional multivariate analysis techniques in dealing with large ToF-SIMS data extracted from metabolite samples. In order to provide more realistic and meaningful interpretation of the results, Non-negative Matrix Factorisation (NMF) is presented. This algorithm is combined with the Bayesian Framework to improve the reliability of the results and the convergence of the algorithm. However, the iterative process involved leads to considerable computational complexity in the estimation procedure. Another novel algorithm is also proposed which is an optimised MCR algorithm within alternating non-negativity constrained least squares (ANLS) framework. It provides a more simple approximation procedure by implementing a dimensionality reduction based on a basis function decomposition approach. The novel and main feature of the proposed algorithm is that it incorporates a spatially continuous representation of ToF-SIMS data which decouples the computational complexity of the estimation procedure from the image resolution. The proposed algorithm can be used as an efficient tool in processing ToF-SIMS data obtained from metabolite samples.
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Houdier, Stéphane. "Cycloisomaltodextrines : synthèse, stéréosélectivité, analyse conformationnelle." Grenoble 1, 1993. http://www.theses.fr/1993GRE10046.
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Au cours de ce travail nous avons prepare les premieres cycloisomaltodextrines (cid) possedant un enchainement glycosidique de type alpha (1-6) et composes analogues des cyclodextrines naturelles (cd). Les tri, tetra, et hexasaccharides cycliques symetriques perbenzyles ont ete synthetises. Deux autres composes cycliques (di et tri), mais non symetriques, ont egalement ete isoles. Amelioration de la stereoselectivite dans la glycosylation par la methode de fraser-reid et coll. Et modification de la methode de mukaiyama et coll. Ont ete les points de departs de cette synthese. Malgre la nature particuliere de la liaison impliquee et la forte contrainte de ces composes cycliques une bonne stereoselectivite pour la glycosylation lineaire et de bons rendements pour l'etape de cycloglycosylation ont pu etre obtenus. L'etude conformationnelle du tetrasaccharide cyclique perbenzyle a ete effectuee par rmn et par mecanique moleculaire. Cette etude a permis de mettre en evidence l'existence en solution de deux conformations privilegiees a basse temperature. Pour ce meme tetrasaccharide cyclique perbenzyle, alors que la spectrometrie de masse indique une interaction avec les cations alcalins, la complexation n'a pu etre mise en evidence par rmn du proton. Cette opposition recouvre peut-etre une difficulte conceptuelle dans l'appreciation de ces phenomenes de complexation, difficulte liee aux caracteres propres de chacune des methodes envisagees ici
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Jakel, Roland. "Linear Dynamic System Analyses with Creo Simulate – Theory & Application Examples, Capabilities, Limitations –." Universitätsbibliothek Chemnitz, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-225992.
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1. Einführung in die Theorie dynamischer Analysen mit Creo Simulate 2. Modalanalysen (Standard und mit Vorspannung) 3. Dynamische Analysen einschließlich Klassifizierung der Analysen; einige einfache Beispiele für eigene Studien (eine Welle unter Unwuchtanregung und ein Ein-Massen-Schwinger) sowie etliche Beispiele größerer dynamischer Systemmodelle aus unterschiedlichsten Anwendungsbereichen 4. Feedback an den Softwareentwickler PTC (Verbesserungsvorschläge und Softwarefehler) 5. Referenzen<br>1. Introduction to dynamic analysis theory in Creo Simulate 2. Modal analysis (standard and with prestress) 3. Dynamic analysis, including analysis classification, some simple examples for own self-studies (shaft under unbalance excitation and a one-mass-oscillator) and several real-world examples of bigger dynamic systems 4. Feedback to the software developer PTC (enhancement requests and code issues) 5. References
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Timmons, Michael Douglas. "EXPLORATIONS IN HOMEOVISCOUS ADAPTATION AND MASS SPECTRAL ANALYSIS OF MEMBRANE LIPIDS." UKnowledge, 2010. http://uknowledge.uky.edu/gradschool_diss/74.
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The focus of this dissertation is centered on the mass spectral analysis of lipids and changes occurring in keeping with the concept of homeoviscous adaptation [1]. Homeoviscous adaptation is the process of modification of membrane lipids in response to environmental stimuli [1]. Dissertation investigations applied this concept to prokaryotic and eukaryotic organisms, and expanded the perception of environmental factors from exogenous organic solvents to intracellular environment.
The field of lipidomics deals with the analysis of phospholipid and fatty acid components of membranes the changes that occur due to environmental stimuli and their biological significance [2-6]. The high sensitivity of mass spectrometry (MS) is an ideal tool for lipidomics allowing detection, quantification and structural elucidation [6]. Coupling of a mass spectrometer to a chromatographic system, such as gas chromatograph (GC), allows the separation of fatty acid methyl esters analytes prior to analysis [7].
The research investigations that comprise this dissertation are divided into three interrelated projects. The first project involved the analysis of composition and structure of Clostridium thermocellum membranes from wild-type and ethanol-adapted strains in response to adaptation of cultures to growth in ethanol. The hypothesis being that adaptation of cultures to growth in ethanol would result in compensatory change to the membrane composition.
Rat mitochondrial fatty acid profiles isolated from brain, liver, kidney and heart tissues were compared. The hypothesis being that differences in cellular environments found among various tissues would be reflected in the mitochondrial membrane composition. These data support the concept that variations to the lipid content of neurological mitochondria may increase susceptibility to the products of oxidative stress.
Lastly, changes in neurological mitochondria as a function of Alzheimer’s disease progression were studied. The hypothesis being that changes to the mitochondrial lipidome would be significantly reflected during advanced stages of AD, in addition to being more prevalent in regions displaying greater pathology.
The three interrelated projects increased our understanding of the boundaries established by the concept of homeoviscous adaptation. Project specific hypotheses were supported by data obtained from these investigations.
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Cheng, Yaping. "Analysis of SELDI mass spectra for biomarker discovery and cancer classification." Thesis, University of Birmingham, 2009. http://etheses.bham.ac.uk//id/eprint/317/.
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The thesis focused on data analysis of surface-enhanced laser desorption/ionisation time-of-flight mass spectrometry (SELDI-TOF MS) for biomarker discovery and cancer classification. It investigated quantitative measures of reproducibility and found that SELDI protein profiles are affected by sample storage and processing procedure. Two new peak alignment algorithms were proposed, one of which achieved the best performance when compared to the existing methods. The assumption of normality of SELDI protein profiles, on which the standard statistical methods are based, was examined. Normality tests and the multiple testing procedures revealed that SELDI protein profiles do not follow normal distributions, implying that it may be reliable to use non-parametric methods for detecting disease-associated proteins. A new normalisation algorithm was proposed, and was shown to give a better improvement of normality compared with the existing methods. An integrated algorithm to discover proteomic biomarkers for cancer diagnosis was proposed and applied to two published SELDI data sets. The results demonstrated that the receiver operating characteristic (ROC) curve method may be more reliable to determine the discriminatory powers of the identified biomarkers compared to Wilcoxon test. The methods for proteomic biomarker discovery presented here may be generalisable and applicable to other mass spectrometry and genomics approaches.
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Beattie, I. G. "Mass spectral techniques for the analysis of compounds connected with food safety." Thesis, Bucks New University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.374817.
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Zheng, Huiru. "New algorithms for the analysis of mass spectral profiles from amphibian data." Thesis, University of Ulster, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272069.
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Graham, Daniel J. "Multivariate analysis of TOF-SIMS spectra from self-assembled monolayers /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/8003.
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Babish, John. "A modal/spectral analysis of mass distribution effects in a fluid-load plate." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/19472.
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Teixeira, Ribeiro Rui Agostinho Fernandes. "Spectral analysis of breast ultrasound data with application to mass sizing and characterization." Thesis, University of Oxford, 2014. http://ora.ox.ac.uk/objects/uuid:8768959f-cc5a-476d-b924-5a5d7df31b8d.
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Ultrasound is a commonly used imaging modality in diagnosis and pre-operative assessment of breast masses. However, radiologists often find it very difficult to correctly size masses using conventional ultrasound images. Consequently, there exists a strong need for more accurate sizing tools to avoid either the removal of an over-estimated amount of tissue or a second surgical procedure to remove margins involved by tumour not removed in the primary operation. In this thesis, we propose a new method of processing the backscattered ultrasound signals from breast tissue (based on the Fourier spectral analysis) to better estimate the degree of echogenicity and generate parametric images where the visibility of breast mass boundaries is improved (SPV parametric image). Moreover, an algorithm is proposed to recover some anatomical structures (particularly, Cooper’s ligaments) which are shadowed during the image acquisition process (LWSPV parametric image). The information from both algorithms is combined to generate a final SPV+LWSPV parametric image. A 20-case pilot study was conducted on clinical data, which showed that the SPV+LWSPV parametric image added useful information to the B-mode image for clinical assessment in 85% of the cases (increase in diagnostic confidence in at least one boundary). Moreover, in 35% of the cases, the SPV+LWSPV parametric image provided a better definition of the entire boundary. Note that the radiologist knew the final diagnosis from histopathology. In addition, the SPV+LWSPV method has the advantage that it uses the I/Q data from a standard ultrasound equipment without the need for additional hardware. On the basis of these facts, we believe there to be a case for further investigation of the SPV+LWSPV imaging as a useful clinical tool in the pre-operative assessment of breast mass boundaries.
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Jakel, Roland. "Berechnung von Schockspektren und praktische Anwendung der dynamischen Stoßanalyse in Creo Elements / Pro Mechanica." Universitätsbibliothek Chemnitz, 2011. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-68407.
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Der Vortrag stellt Idee und Grundlagen der Berechnung von Schockantwortspektren dar. Er zeigt, wie man exemplarisch für einen Halbsinusstoß das Schockantwortspektrum in der PTC FEM-Software Creo Elements / Pro Mechanica berechnen kann. Die Schockantworten eines Ein- und Zweimassenschwingers werden sowohl zeitaufgelöst als auch über die dynamische Stoßanalyse berechnet. Die modalen Superpositionsmethoden "Absolute Summe" und "SRSS" (Square Root of the Sum of the Squares - geometrischer Mittelwert) werden vorgestellt. Als reales Beispiel werden Schockanalysen für verschiedene Halbsinusimpulse mit einem Wärmebildgerät der Firma Carl Zeiss Optronics GmbH durchgeführt und mit einer zeitaufgelösten Analyse verglichen. Abschließend wird auf die Erzeugung von Antwortspektren für die Substrukturauslegung eingegangen<br>The presentation explains idea and fundamentals of shock response spectra analysis. With help of the PTC FEM-software Creo Elements / Pro Mechanica the shock response spectra (SRS) for an exemplary half sine shock is calculated. The shock response of a one-mass and a two-mass oscillator are analyzed per dynamic time as well as per dynamic shock analysis. The modal superposition methods "absolute sum" and "SRSS" (Square Root of the Sum of the Squares) are explained. The method is applied for different half sine shocks on a realistic example: A thermal imaging system of the company Carl Zeiss Optronics GmbH. Finally, the creation of response spectra for global-local analysis is explained
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Liang, Zhenmin. "High precision Fourier transform ion cyclotron resonance mass spectral analysis of polymers and metal complexes /." The Ohio State University, 1990. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487685204968068.
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Nakano, Yushi. "Stochastic Stability of Partially Expanding Maps via Spectral Approaches." Kyoto University, 2015. http://hdl.handle.net/2433/200463.
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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(人間・環境学)<br>甲第19200号<br>人博第741号<br>新制||人||178(附属図書館)<br>27||人博||741(吉田南総合図書館)<br>32192<br>京都大学大学院人間・環境学研究科共生人間学専攻<br>(主査)教授 宇敷 重廣, 教授 森本 芳則, 准教授 木坂 正史<br>学位規則第4条第1項該当
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Amaduzzi, Alberto. "Enzymes' characterization via spectral analysis of the Laplacian associated to their relative contact maps." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amslaurea.unibo.it/23899/.
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The main motivation for my thesis is the believe that global properties of enzymes areessential for a complete understanding of their behaviors. In my thesis, in particular,I investigate qualitative properties of enzymes via spectral techniques associated to thegraph Laplacian. I try to apply visualization techniques to understand similarities anddissimilarities among different enzymes’ structures, encoded in adjacency matrices re-trieved from coordinate data in online available datasets. The purpose is to make anexploration of features and see whether these techniques, that are used extensively inliterature for visual discrimination tasks, are also useful for these biological entities.I have tried to design a size-independent analysis that would be able to differentiateamong different taxonomies, different catalytic properties and different environmentsassociated to enzymes. This attempt provided useful hints for the analysis of enzymeproperties, even if as a final remark the dependence from enzyme size is still found inthe Laplacian eigenvalue spectrum.
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Li, Fang Owens Kevin G. "Development of a genetic algorithm-correlation analysis (GA/CA) program for classification of chemical compounds using mass spectral data /." Philadelphia, Pa. : Drexel University, 2008. http://hdl.handle.net/1860/2803.
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Troyer, Jon S. "Spectral-Timing Analysis of Kilohertz Quasi-Periodic Oscillations in Neutron Star Low Mass X-Ray Binaries." Thesis, Wayne State University, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10747548.
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<p> Kilohertz quasi-periodic oscillations or kHz QPOs are X-ray intensity variations observed in neutron star low-mass X-ray binary (LMXB) systems. In such systems, matter is transferred from a secondary low-mass star to a neutron star via the process of accretion. kHz QPOs occur on the timescale of the inner accretion flow and may carry signatures of the physics of strong gravity (<i>c<sup>2</sup> ~ GM/R</i>) and possibly clues to constraining the neutron star equation of state (EOS). No model to date has been able to illuminate the origin of kHz QPOs. Spectral-timing is a set of analysis techniques useful in deriving information about the nature of physical processes occurring within the accretion flow on the timescale of the kHz QPO. We present a comprehensive study of spectral-timing products of kHz QPOs from systems where data is available in NASA’s <i>Rossi X-ray Timing Explorer</i> (<i>RXTE</i>) archive to demonstrate the promise of these techniques and to gain insights regarding the origin of kHz QPOs. Using data averaged over the entire <i>RXTE</i> archive, we show correlated time-lags as a function of QPO frequency and energy, as well as energy-dependent covariance spectra for the various LMXB systems where spectral-timing analysis is possible. The similarity in trends in all sources suggest a common physical origin for kHz QPOs across the population. The diferences in results between lower and upper kHz QPOs lend further support to the evidence of the differing nature of the lower and upper kHz QPOs.</p><p>
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Casper, Brent. "DEVELOPMENT OF AN EXTRACTION METHOD FOR THE MASS SPECTRAL ANALYSIS OF ORGANIC GUNSHOT RESIDUE FROM CLOTHING." UKnowledge, 2015. http://uknowledge.uky.edu/chemistry_etds/48.
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This dissertation will focus on the extraction of volatile organic compounds associated with gunshot residue from articles of clothing, followed by analysis with mass spectrometry. During the discharge of a weapon, a cloud of volatile organic gunshot residue (OGSR) is dispersed around a firearm. This will create a high probability of transfer between the OGSR and the clothing of individuals who are near a discharged weapon.
The first part of this dissertation will be the development of a method for removal of volatile OGSR from articles of clothing. Extraction of OGSR will be completed by solid phase microextraction (SPME), followed by separation and analysis by gas chromatography-mass spectrometry (GC/MS). Many parameters will require optimization for proper extraction of OGSR from articles of clothing. Following development of a SPME procedure, figures of merit were determined such as linearity and limits of detection/quantification, obtaining levels of detection of 0.206 ng/cm2 on a 100 cm2 cotton cloth. Applications of this extraction method were investigated including the determination of the distance OGSR travels from a discharged weapon and the extraction of OGSR with different clothing materials by SPME.
The second part of this dissertation will focus on the development of an on-line solvent extraction method for removal of OGSR from articles of clothing, followed by analysis with paper spray mass spectrometry. Issues using SPME of certain types of clothing materials required the development of an alternative method for removal of OGSR from articles of clothing. Use of an on-line solvent extraction technique of OGSR from articles of clothing followed by analysis with paper spray mass spectrometry allowed for detection of OGSR at comparable levels to a headspace SPME procedure. Use of paper spray with an ion trap mass spectrometer permitted the soft ionization of OGSR compounds followed by tandem mass spectrometry to obtain structural information.
Extraction of OGSR from articles of clothing has potential to determine if an individual was present during the discharge of a firearm. Extraction of OGSR from articles of clothing will provide an alternative to traditional methods of gunshot residue analysis currently in use.
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Bowman, Amanda. "Lipidomic Analysis of Single Cells and Organelles Using Nanomanipulation Coupled to Mass Spectrometry." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849662/.
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The capability to characterize disease states by way of determining novel biomarkers has led to a high demand of single cell and organelle analytical methodologies due to the unexpected heterogeneity present in cells of the same type. Lipids are of particular interest in the search for biomarkers due to their active roles in cellular metabolism and energy storage. Analyzing localized lipid chemistry from individual cells and organelles is challenging however, due to low analyte volume, limited discriminate instrumentation, and common requirements of separation procedures and expenditure of cell sample. Using nanomanipulation in combination with mass spectrometry, individual cells and organelles can be extracted from tissues and cultures in vitro to determine if heterogeneity at the cellular level is present. The discriminate extraction of a single cell or organelle allows the remainder of cell culture or tissue to remain intact, while the high sensitivity and chemical specificity of mass spectrometry provides structural information for limited volumes without the need for chromatographic separation. Mass analysis of lipids extracted from individual cells can be carried out in multiple mass spectrometry platforms through direct-inject mass spectrometry using nanoelectrospray-ionization and through matrix-assisted laser/desorption ionization.
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Herzog, Ronny. "Novel concepts for lipid identification from shotgun mass spectra using a customized query language." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2012. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-90497.
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Lipids are the main component of semipermeable cell membranes and linked to several important physiological processes. Shotgun lipidomics relies on the direct infusion of total lipid extracts from cells, tissues or organisms into the mass spectrometer and is a powerful tool to elucidate their molecular composition. Despite the technical advances in modern mass spectrometry the currently available software underperforms in several aspects of the lipidomics pipeline. This thesis addresses these issues by presenting a new concept for lipid identification using a customized query language for mass spectra in combination with efficient spectra alignment algorithms which are implemented in the open source kit “LipidXplorer”.
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Casavecchia, Benedetta. "Studying synthetic column density maps and absorption spectra from galactic wind models." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022. http://amslaurea.unibo.it/25361/.
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Galactic winds are multi-phase outflows that probe how feedback regulates the mass and metallicity of galaxies. Their cold phase, mainly observable with absorption lines, is often detected hundreds to thousands of pc away from the galactic plane and with velocities of hundreds of km $\rm s^{-1}$. To understand observations, it is important to theoretically study how such lines are produced via numerical simulations of cloud systems exposed to winds and starburst UV backgrounds. In this thesis we study the thermodynamics, ion populations, and ion absorption lines of cold and warm radiative clouds evolving from magnetised wind-cloud systems and an unmagnetised shock-multicloud model. We account for radiative cooling with two different cooling floors and magnetic fields with two different orientations.
In our wind-cloud simulations, cold clouds survive the interaction with the wind for longer, since they are less exposed to instabilities, than warmer clouds. Magnetic fields have a larger influence on warm clouds than in cold clouds. If transverse to the wind direction, the field creates a shield that confines the expansion of the cloud, delaying its evaporation. In our shock-multicloud simulation, cold gas at large distances is not accelerated by ram-pressure, but, instead, precipitates from mixed gas out of thermal equilibrium. To study ion populations and create synthetic spectra, we developed a flexible python interface to link our PLUTO simulations to TRIDENT via the YT-package infrastructure and CLOUDY. Our ion population analysis reveals that setting different cooling floors and magnetic fields affect the column densities of several ions. H\,{\sc i}, O\,{\sc vi}, Mg\,{\sc ii}, C\,{\sc iii}, and Si\,{\sc iv} are more sensitive to the cooling floors, and H\,{\sc i}, Mg\,{\sc ii}, C\, {\sc iii}, and Si\, {\sc iv} can also trace the initial magnetic field direction, making them good candidates for comparisons with observations.
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Hou, Z., K. Aylor, B. A. Benson, L. E. Bleem, J. E. Carlstrom, C. L. Chang, H.-M. Cho, et al. "A Comparison of Maps and Power Spectra Determined from South Pole Telescope and Planck Data." IOP PUBLISHING LTD, 2018. http://hdl.handle.net/10150/626533.
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We study the consistency of 150 GHz data from the South Pole Telescope (SPT) and 143 GHz data from the Planck satellite over the patch of sky covered by the SPT-SZ survey. We first visually compare the maps and find that the residuals appear consistent with noise after accounting for differences in angular resolution and filtering. We then calculate (1) the cross-spectrum between two independent halves of SPT data, (2) the cross-spectrum between two independent halves of Planck data, and (3) the cross-spectrum between SPT and Planck data. We find that the three cross-spectra are well fit (PTE = 0.30) by the null hypothesis in which both experiments have measured the same sky map up to a single free calibration parameter-i.e., we find no evidence for systematic errors in either data set. As a by-product, we improve the precision of the SPT calibration by nearly an order of magnitude, from 2.6% to 0.3% in power. Finally, we compare all three cross-spectra to the full-sky Planck power spectrum and find marginal evidence for differences between the power spectra from the SPT-SZ footprint and the full sky. We model these differences as a power law in spherical harmonic multipole number. The best-fit value of this tilt is consistent among the three cross-spectra in the SPT-SZ footprint, implying that the source of this tilt is a sample variance fluctuation in the SPT-SZ region relative to the full sky. The consistency of cosmological parameters derived from these data sets is discussed in a companion paper.
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Christison, Krege Matthew. "Exploring the Molecular Origin of Jet Fuel Thermal Oxidative Deposition Through Statistical Analysis of Mass Spectral Data and Pyrolysis Gas Chromatography/Mass Spectrometry of Deposits." Scholarly Commons, 2019. https://scholarlycommons.pacific.edu/uop_etds/3639.
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ASTM D3241 (Standard Test Method for Thermal Oxidation Stability of Aviation Turbine Fuels) measures the thermal oxidative stability of jet fuels under elevated temperature and pressure conditions. When jet fuels fail ASTM D3241, either at the refinery or in the distribution system, there can be supply disruptions and financial losses. Understanding the causes of poor thermal oxidative stability in jet fuels could help prevent or mitigate issues. In order to develop a deeper understanding of the molecular precursors that lead to ASTM D3241 failures, a number of analytical methodologies and data treatment techniques have been developed, applied, and reported here. Statistical analysis of LC/MS ESI data from jet fuels with varying thermal oxidative stabilities allows for the identification of molecules that are significant to ASTM D3241 failures. Differential statistical analysis of LC/MS ESI data from jet fuels before and after thermal oxidative stressing in a QCM reactor elucidates which significant molecules are being consumed during oxidation and which molecules are increasing in abundance. The analysis of thermal oxidative deposits that form during thermal oxidative stressing in the QCM reactor allows for the insight into the molecular components of the deposits. Attapulgus clay removes the polar molecules that lead to thermal oxidative stability issues in the refinery. Extraction of Attapulgus clay that has been used in a refinery to filter jet fuel with a series of solvents removes the polar molecules into a series of fractions. The subsequent analysis of the fractions by comprehensive GCxGC/MS leads to the identification of the different homologous series of molecules that are removed by the clay.
The analyses developed and employed here are shown to be particularly useful for the analysis of trace polar nitrogen and oxygen containing molecules. Similar homologous series of molecules are identified across all of the different analyses. It is also clear from some of the analyses, along with previously reported data in the literature, that reactive sulfur-containing molecules are significant to poor thermal oxidative stability as measured by ASTM D3241 and to the formation of thermal oxidative deposits. There is still an opportunity to find methodologies to better characterize the sulfur species present and correlate them to the data that is reported here.