Dissertations / Theses on the topic 'Analysis ICPC'

Nigeria is ranked as one of the most corrupt countries in the world. Since it regained democratic status in 1999, successive governments have made several attempts to ameliorate corruption. One such attempt is the establishment of the Independent Corrupt Practices and Other Related Offences Commission (ICPC), in 2000. This study examined the manner in which the ICPC conceptualises corruption, including its forms and consequences. It also examined what measures it proposes to combat corruption. The ICPC’s approach to corruption is evaluated in relation to the way corruption is understood in scholarly literature, especially within the education sector. The rationale for the study is that the potential effectiveness of anti-corruption activities is based, in part, on the appropriacy of the understanding of corruption that informs such activities. To carry out this study, the annual reports of the ICPC for the period from 2009 to 2013 were analysed. These documents describe all the activities of the Commission for these years. A rigorous textual analysis was conducted, focusing on descriptions of activities of the Commission that applied across sectors, as well as descriptions of activities related to education, specifically. The strongest conclusion reached is that the approach of the ICPC could potentially be strengthened considerably if it were to be informed by engagement with scholarship relating to corruption. However, this engagement is itself subject to political will. Where there is no such engagement, or where political will is not strong, it is unlikely that the strategies that are adopted would be effective.

Magister Public Health - MPH<br>Background: The Provincial Government Western Cape (PGWC) Department of Health identified a lack of data on inpatient diagnoses and procedures in a form suitable to use for operational, strategic as well as financial health care planning. The only format in which diagnostic and procedure data was available was a paper based one encompassing individual patient notes in folders and discharge summaries. Making the data available in a coded format within an electronic database would facilitate storage, analysis and utilisation of that data for health service planning. Recognising the lack of availability of such coded data, this study was undertaken to evaluate different coding systems for their ability to code data in order to assist in deciding which coding systems best fit the need to facilitate easy and accurate recording of data on diagnoses and procedures from patient records. The identification of the most appropriate coding system for the context in which the PGWC Department of health functions should facilitate the easy recording, storage and retrieval of data that is accurate, reliable and useful for management decision making and would support optimal patient care. Aim: The aim of the study was to evaluate a selection of potentially suitable coding systems in order to determine which would be best able to code public sector district and regional hospital diagnostic and procedure data in the Western Cape Province. Method: A cross sectional analytical study design was used. Discharge diagnosis and procedure data were extracted from 342 patient folders from 3 district and 3 regional public hospitals in the Western Cape. This yielded 221 different diagnostic concepts and 126 different procedure concepts. The diagnostic concepts were further grouped into “all” diagnostic concepts recorded, diagnostic concepts recorded as “symptoms only” and diagnostic concepts recorded as “proper diagnoses”. The diagnostic coding systems evaluated were ICD-10 (International Classification of Diseases), ICPC-2 (International Classification of Primary Care 2nd edition) and ICD-10 Condensed Morbidity List. The procedure coding systems evaluated were CCSA-2001 (Current Procedure Terminology for South Africa) ICD-9-CM (International Classification of Diseases Clinical Modification 9th revision) and ICPC-2. The diagnoses and procedures were then coded in all of the coding systems being evaluated. Each diagnosis and procedure concept was matched with its representing concept in the coding system and scored according to the ability of the coding system to provide an “exact” match which was scored as (3) or a “partial” match scored as (2) or a “poor” match scored as (1) or “no” match scored as (0). Results: ICD-10 was better able to code diagnoses obtained from district and regional hospitals in the Western Cape compared to ICPC-2 and ICD-10 Condensed Morbidity list. For all recorded diagnostic concepts, ICD-10 was able to score 82% of the concepts as either an “exact” or a “partial” match compared to 79% in ICPC-2 and 30% in ICD-10-CL. ICD-10 consistently performed best across different stratification of diagnostic concepts namely concepts recorded as “proper diagnoses”, concepts recorded from regional hospitals only, concepts recorded from district hospitals only, concepts designated as “common diagnoses” and for concepts designated as “very common diagnoses”. In addition ICD-10 had zero diagnostic concepts for which “no match” could be found. CCSA -2001 proved to be the best coding system for coding procedures across all hospitals with an overall percentage of “exact” and “partial” matches of 83% compared to 65% for ICD-9-CM and 39% for ICPC-2 and also proved to be best across all strata. Conclusion: There were striking differences between the evaluated coding systems with regard to their ability to code diagnoses and procedures in the evaluated district and regional hospitals in the Western Cape Province. ICD-10 covers the scope of clinical diagnoses in more accurate and specific detail than ICPC-2 and ICD-10 CL. Though ICPC-2 is simpler and easier to use than ICD-10, it is not as detailed and specific as the latter but it proved ideal for symptoms rather than for specific diagnoses. ICD-10 Condensed Morbidity List was shown to be inadequate for coding diagnoses. However the difference between the two, although statistically significant were not very large and given the ease of use of ICPC-2, it could be recommended for use. As for procedures CCSA-2001 was assessed as being the most appropriate for coding procedures recorded in this setting compared to the other coding systems. ICPC-2 performed poorest for coding procedures across all evaluated settings and thus would be inappropriate to use. ICD-10 in most comparisons performed second best to ICPC-2 in terms of coding ability for diagnoses and could be considered for recommendation as a diagnostic coding tool.

Les travaux de thèse portent sur le développement de méthodes pour la caractérisation des nanoparticules (NPs) de dioxyde de titane (TiO2) dans les aliments. L’étude a été séparée distinctement en deux axes. Le développement de la méthode AF4-ICP-MS (I) au sein de la Plateforme Nano-Sécurité du CEA de Grenoble et le développement de la méthode Sp-ICP-MS (II) au sein du Laboratoire de la Sécurité Aliments de l’Anses à Maisons-Alfort.Pour le premier axe, les interactions électrostatiques entre les particules et la membrane de l’AF4 ont été étudiées. La charge de surface (potentiel zêta) a été mesuré pour différentes type de particule et membrane en fonction de plusieurs paramètres du solvant tel que le pH, la force ionique ainsi que la présence de tensio-actifs. Suite aux nombreuses analyses effectuées plusieurs conditions de solvant ont été identifiées comme favorable à la répulsion électrostatique entre les particules et la membrane ce qui permettrai de diminuer les pertes de particules au niveau de la membrane. Plusieurs conditions ont donc été testées directement pour l’analyse de NPs de TiO2 en AF4-ICP-MS. Il a ainsi été montré que les conditions favorisant les répulsions électrostatiques permettaient d’améliorer le taux dé récupération des particules au niveau du système AF4. Cependant les analyses ont aussi montré que les NPs de TiO2 n’étaient pas suffisamment dispersées pour pouvoir obtenir une distribution en taille fiable.Le second volet de la thèse, a eu pour but, dans un premier temps, d’optimiser le traitement de données de la méthode Sp-ICP-MS. Plusieurs améliorations ont été réalisées comme le calcul automatique du seuil bruit de fond-particule, le calcul de l'efficacité de transport où encore l'ajout de paramètres de contrôle qualité. Ce traitement de données a ensuite été comparée à un logiciel dédié aux analyses par Sp-ICP-MS et a permis de mettre en avant que la feuille de calcul interne donne des résultats avec une meilleure justesse, tout en fournissant des paramètres supplémentaires.Dans un second temps une optimisation de la méthode Sp-ICP-MS a été réalisée. Plusieurs paramètres ont donc été évalués comme le choix de l’isotope de titane, le temps d’acquisition, le type de solvant pour disperser les particules, ainsi que le mode de prélèvement de l’échantillon et son débit.Enfin, plusieurs aliments ont été analysés après avoir mis en place un protocole d’extraction des NPs. Les résultats obtenus ont permis de déterminer une distribution en taille des NPs de TiO2 présentes dans les échantillons<br>The thesis focuses on the development of methods for the titanium dioxide (TiO2) nanoparticles (NPs) characterization in food products. The study was separated distinctly into two axes. The development of the AF4-ICP-MS (I) method within the CEA Nano-Safety Platform in Grenoble and the development of the Sp-ICP-MS (II) method within the Food Safety Laboratory of the Anses in Maisons-Alfort.For the first axis, the electrostatic interactions between the particles and the AF4 membrane were studied. The surface charge (zeta potential) was measured for particles and membranes depending on several solvent parameters such as pH, ionic strength and the presence of surfactants. Following the several analyzes carried out, several solvent conditions have been identified as promoting the electrostatic repulsion between the particles and the membrane, which will make it possible to reduce the losses of particles at the level of the membrane. Several conditions were therefore directly tested for NPs analysis of TiO2 in AF4-ICP-MS. It has thus been shown that the conditions favoring electrostatic repulsions make it possible to improve the efficiency of the particles at the level of the AF4 system. However, the analyzes also showed that the TiO2 NPs were not sufficiently dispersed to obtain a reliable size distribution.The second part of the thesis aimed at first optimizing the data treatment of the Sp-ICP-MS method. Several improvements have been made such as the automatic calculation of the background-particle threshold, the calculation of the transport efficiency or the addition of quality control parameters. This data treatment was then compared to a software dedicated to analyzes by Sp-ICP-MS and made it possible to highlight that the internal spreadsheet gives results with a better accuracy, while providing additional parameters.In a second time an optimization of the Sp-ICP-MS method was carried out. Several parameters were therefore evaluated such as the choice of the titanium isotope, the acquisition time, the type of solvent to disperse the particles, as well as the sample collection mode and its flow rate.Finally, several foods were analyzed after setting up an extraction protocol for NPs. The results obtained made it possible to determine a size distribution of the NPs of TiO2 present in the samples

The direct injection of solids/water slurries into an inductively coupled plasma (ICP) spectrometer offers a rapid and easy method for the analysis of major, minor, and trace elements in coal, coal ash, cements, and refractory materials. In this study aqueous slurries of 6 coals were prepared by milling with a stirred-ball slurry attritor mill and an air impact pulverizer. ICP analysis values obtained for the six coals by the two different grinding methods were compared. Five coal ashes and five check standard reference materials were ground by an attritor mill and analyzed with an ICP spectrometer. Slurries of standard reference materials prepared in the same manner were used to calibrate the spectrometer. The results indicate that the ICP method is poor for coal/water slurries. The recovery and analysis of major, minor, and trace elements in coal ash, slag, and refractory materials is good using the slurry ICP method. These results suggest that this method may be applicable for the analysis of finely divided solid samples using inductively coupled plasma-atomic emission spectrometry.

The analysis of metals is now a major application area for ICP-AES, however, the technique suffers from both spectral and non-spectral interferences. This thesis details the application of univariate and multivariate calibration methods for the prediction of Pt, Pd, and Rh in acid-digested and of Au, Ag and Pd in fusion-digested autocatalyst samples. Of all the univariate calibration methods investigated matrix matching proved the most accurate method with relative root mean square errors (RRMSEs) for Pt, Pd and Rh of 2.4, 3.7, and 2.4 % for a series of synihelic lest solutions, and 12.0, 2.4, and 8.0 % for autocatalyst samples. In comparison, the multivariate calibration method (PLSl) yielded average relative errors for Pt, Pd, and RJi of 5.8, 3.0, and 3.5 % in the test solutions, and 32.0, 7.5, and 75.0 % in the autocatalyst samples. A variable selection procedure has been developed enabling multivariate models to be built using large parts of the atomic emission spectrum. The first stage identified and removed wavelengths whose PLS regression coefficients were equal to zero. The second stage ranked the remaining wavelengths according to their PLS regression coefficient and estimated standard error ratio. The algorithms were applied to the emission spectra for the determination of Pt, Pd and Rh in a synthetic matrix. For independent test samples variable selection gave RRMSEs of 5.3, 2.5 and 1.7 % for Pt, Pd and Rh respectively compared with 8.3, 7.0 and 3.1 % when using integrated atomic emission lines. Variable selection was then applied for the prediction of Au, Ag and Pd in independent test fusion digests. This resulted in RRMSEs of 74.2, 8.8 and 12.2 % for Au, Ag and Pd respectively which were comparable to those obtained using a more traditional univariate calibration approach. A preliminary study has shown that calibration drift can be corrected using Piecewise Direct Standardisation (PDS). The application of PDS to synthetic test samples analysed 10 days apart resulted in RRMSEs of 4.14, 3.03 and 1.88%, compared to 73.04, 44.39 and 28.06 % without correction, for Pt, Pd, and Rh respectively.

Both herpes simplex virus type-1 (HSV-1) and herpes simplex virus type-2 (HSV-2) are human pathogens that are capable of causing significant disease. More than 600 million people are infected with HSV-2 genital herpes and every day >40,000 new HSV-2 infections are transmitted to naïve recipients. The public health community has long agreed that a preventative vaccine is necessary to reduce the prevalence of HSV-2, but we continue to lack a vaccine to prevent the spread of this sexually transmitted disease. Herpes simplex viruses (HSV) establish a life-long infection in their host where they alternate between a state of latency and productive replication. One of principle determining factors of whether HSV reactivates from a latent state to cause disease is the accumulation of the immediate early viral protein, infected cell protein 0 (ICP0). ICP0 is a potent transactivator of HSV mRNA synthesis. However, in addition to the nuclear transactivating function of ICP0, our lab demonstrated that at later times during infection, ICP0 translocates from the nucleus to the cytoplasm where it reorganizes the host microtubule network (PLoS ONE 5(6): e10975). In the first part of my dissertation, we used the anti-neoplastic drug paclitaxel to determine if ICP0’s microtubule-reorganizing activity is required for efficient replication of HSV- 1. Surprisingly, we observed that paclitaxel prevented ICP0 from dispersing cellular microtubules and inhibited the spread of HSV-1 and HSV-2. Paclitaxel reduced HSV-1 plaque size by up to 100-fold, and inhibition of viral spread was proportional to the efficiency with which doses of paclitaxel stabilized microtubules against ICP0-induced dispersal. Analysis of infected Vero cells confirmed that paclitaxel treatment did not reduce the efficiency of HSV-1 mRNA, protein, DNA, or virion synthesis by more than 3-fold. In contrast, paclitaxel treatment caused an ~20-fold decrease in infectious virus release from HSV-1 infected cells. Comparison of ICP0+ versus ICP0- viruses yielded genetic evidence that ICP0 promotes infectious virus release from HSV-1-infected cells. These results provide the first evidence suggesting that ICP0’s microtubule-reorganizing activity may promote the release of infectious virus from HSVinfected cells. In the second part of my dissertation, I focus less on the basic-science quest to elucidate the function of ICP0 but instead focus on characterizing the antibody response elicited by a highly protective HSV-2 ICP0- vaccine that was developed in our lab. Specifically, despite the belief that virion glycoproteins such as glycoprotein D (gD-2) are the dominant antigens of herpes simplex virus 2 (HSV-2) we have demonstrated mice immunized with a live HSV-2 ICP0- mutant virus, HSV-2 0ΔNLS, are 10 to 100 times better protected against genital herpes than mice immunized with a HSV-2 gD subunit vaccine (PLoS ONE 6:e17748). In light of these results, we sought to determine which viral proteins were the dominant antibody-generators (antigens) of the live HSV-2 0ΔNLS vaccine. Western blot analyses indicated the live HSV-2 0ΔNLS vaccine elicited an IgG antibody response against 9 or more viral proteins. Many antibodies were directed against infected-cell proteins of >100 kDa in size, and only 10 ± 5% of antibodies were directed against gD. Immunoprecipitation (IP) of total HSV-2 antigen with 0ΔNLS antiserum pulled down 19 viral proteins. Mass spectrometry suggested 44% of immunoprecipitated viral peptides were derived from two HSV-2 infected cells proteins, RR-1 and ICP8, whereas only 14% of immunoprecipitated peptides were derived from HSV-2's thirteen glycoproteins. Collectively, the results suggest the immune response to the live HSV-2 0ΔNLS vaccine includes antibodies specific for infected cell proteins, capsid proteins, tegument proteins, and glycoproteins. This increased breadth of antibody-generating proteins may contribute to the live HSV-2 vaccine's capacity to elicit superior protection against genital herpes relative to a gD subunit vaccine. In the final section of my dissertation, I focus on the construction of stable Vero cell lines using a system that relies on Sleeping Beauty transposase to introduce two genetic elements into the chromosomes of target cells: 1. a Tet-regulatable gene-of-interest driven by the VP16- inducible HSV-1 ICP0 promoter and 2. a highly expressed bicistronic gene that expresses the Tet-repressor protein and a puromycin selection marker. The modified bidirectional HSV-1 ICP0 promoter used in this novel expression system 1. drives constitutive expression of a cell surface marker (tNGFR) from the reverse side of the ICP0 promoter, while 2. the Tetregulatable, forward side of the ICP0 promoter allows the expression of a downstream gene-ofinterest to be regulated over an ~100-fold range of gene expression through doxycyclineinduced derepression and induction with VP16. Using this system, stable and regulatable Vero cell lines are reproducibly obtained within one month of initial transfection by using puromycin selection followed by fluorescence-activated cell sorting (FACS) to isolate a pure population of tNGFR+ cells that contain the target gene-of-interest. Vero cell lines that carry a toxic gene, such as HSV-1 ICP0, can be routinely passaged and maintained in cell culture because basal expression of the gene-of-interest can be reduced to low to undetectable levels. However, when the same cell lines are de-repressed, they express adequate levels of HSV-1 ICP0 or HSV-1 origin-binding protein (OBP) to complement an HSV-1 ICP0- mutant . These data suggest this novel gene expression system may have broad uses in biological research because it allows for the efficient generation of stable cell lines that express a gene-of-interest in a highly regulatable manner.

En complément des analyses de concentration et de spéciation, les analyses des isotopes stables du mercure par MC-ICP-MS sont à l’heure actuelle un outil majeur pour tracer les sources et les transformations de cet élément dans l’environnement. Cette thèse propose le développement de techniques de pré-concentrations couplées au MC-ICP-MS afin de réaliser des analyses isotopiques de mercure au niveau du ng.L-1 (Ultra-trace). La stratégie de pré-concentration en ligne va générer des signaux transitoires courts dont la gestion en MC-ICP-MS représente un réel défi. Afin d’y répondre, une méthode de traitement de données adaptée à ce type de signaux ainsi qu’une méthode de correction du phénomène de dérive isotopique ont été développées. Dans le but de déterminer des compositions isotopiques en mercure total à de faibles concentrations, le couplage d’une génération de vapeur froide, d’une double amalgamation sur or (CVG-DGA) et d’un MC-ICP-MS a été développé. Cette nouvelle technique donne des précisions externes de l’ordre de 0.20 à 0.30‰ (2SD) pour des concentrations en mercure de 5 ng.L-1 en solution. Cette thèse présente également une nouvelle méthode d’analyse isotopique par espèce chimique (CSIA) réalisée à l’aide du couplage d’une chromatographie en phase gazeuse équipée d’un injecteur PTV (GC-PTV) et d’un MC-ICP-MS. Celle-ci permet l’analyse isotopique de plusieurs espèces chimiques avec des précisions externes de l’ordre de 0.30 à 0.40‰ (2SD) pour des concentrations en mercure de 150 ng.L-1 dans des échantillons biologiques.Les développements analytiques de cette thèse ont permis de mesurer directement et de façon automatisée des compositions isotopiques de mercure à des niveaux d’ultra-trace (jusqu’à 5ng.L-1) tout en conservant des précisions compatibles avec les principales questions environnementales posées. Ceci va permettre d’analyser des compartiments environnementaux contenant de faibles quantités de mercure (eaux naturelles, planctons,…) et ouvre ainsi de nouvelles perspectives pour une meilleure compréhension du cycle bio-géochimique du mercure<br>In addition to the quantitative and speciation analysis, the analysis of mercury stable isotopes by MC-ICP-MS are now a tool of choice to track sources and pathways of this element in the environment. This PhD thesis presents the development of hyphenation between pre-concentration techniques and MC-ICP-MS to measure isotopic composition of mercury at ng.L-1 levels (Ultra-trace). The on-line pre-concentration strategy will create short transient signals which represent a real challenge for MC-ICP-MS. In order to solve it, a data treatment strategy for this particular signals and a correction method for the isotopic drift were developed.The hyphenation between a cold vapor generation, a dual gold amalgamation (CVG-DGA) and a MC-ICP-MS was developed to determine total mercury isotopic composition. This new technique gives external precisions ranging from 0.20 to 0.30‰ (2SD) for Hg concentration in solution of 5 ng.L-1. This PhD thesis also reports a new method to perform mercury compound specific isotopic analysis (CSIA) using a gas chromatography fitted with a PTV injector (GC-PTV) coupled to the MC-ICP-MS. This allows the isotopic analysis of several species with external precisions ranging from 0.30 to 0.40‰ (2SD) for mercury concentration down to 150 ng.L-1 in biological samples.The analytical developments proposed in this PhD thesis allows to automatically and directly measure mercury isotopic compositions at ultra-trace levels (down to 5 ng.L-1) while keeping precision compatible with main environmental questions. This will allow to analyze environmental compartment containing very low amount of mercury (natural waters, planktons,…) and then open new perspectives for a better understanding of the bio-geochimical cycle of mercury

<p>The performance of different types of nebulisers: Vulkan direct injection nebuliser (Vulkan DIN), direct injection high efficiency nebuliser (DIHEN), microconcentric nebuliser coupled to cyclonic or double pass spray chamber (MCN-C or MCN-DP, respectively) was investigated and compared when used for sample introduction to ICP-MS or ICP-OES. With ICP-OES, in axial viewing mode, intensity distributions across the radius of the plasma (radial intensity profiles) were determined for different spectral lines with Esum 1.85-15.41 eV to determine fundamental plasma properties for various matrices using Vulkan DIN and MCN-C. The results showed that with the MCN-C the ionisation temperature (Tion) was about the same across the measured region of the plasma (±3.0 mm) whereas with the Vulkan DIN the Tion was significantly lower in the centre of the plasma. A large deviation from local thermodynamic equilibrium, as well as deteriorated stability, was observed for the plasma when using the Vulkan DIN.</p><p>With ICP-MS noise power spectra (NPS) were generated to identify sources of noise. NPS showed that the magnitude of white noise for the tested sample introduction systems decreased in the following order: Vulkan DIN > DIHEN > MCN-C > MCN-DP. This order follows the decrease of mean droplet size and span of the size distribution, indicating that the white noise is caused by spatial and temporal non-uniform desolvation and ionisation. Another source of noise arose from the peristaltic pump and the magnitude of pump interference noise decreased in the following order: DIHEN > MCN-C/DP > Vulkan DIN. Mains power interference noise and 1/f noise were lower for the direct injection nebulisers compared to the spray chamber systems. The contribution or effects of these noise components on relative standard deviations of steady-state ion-count rate and isotope ratio measurements is discussed in this thesis.</p><p>Aerosols generated by the Vulkan DIN and the DIHEN were also directly characterised using Particle Dynamic Analysis. The Vulkan DIN produced particles with a mean diameter of ~30 µm and a size distribution between 2-80 µm. With the DIHEN the corresponding values were ~11 µm and 1-40 µm, respectively, with a few particles at 55-78 µm. The mean velocity of particles from the Vulkan DIN was ~10 m s-1 and from the DIHEN ~18 m s-1. The lower velocity allows longer residence time counteracting the effects of the larger droplet size.</p>

This Master's thesis is dealing with elementary analysis of milk. Theoretical part describes general characteristics, terminology with basic legislature and classification of milk. Large part is focused on chemical composition, especially on description of mineral substances selected for analysis in experimental part of this thesis. Choices of elementary analysis and preparation of samples for ICP-OES method conducted by other authors are also mentioned. Specification of emission spectrometry with inductively coupled plasma is crucial, a technique used for purposes of this dissertation. Experimental part deals with preparation of samples, approach of analysis and processing of measured results. The aim of this part is to compare concentration of analyzed elements in different kinds of milk. Samples from 15 different kinds of milk were used for analysis, which were determined by ICP-OES method. Results were compared to each other in discussion as well as with results from other authors.

Ce manuscrit de thèse intègre l'application de plusieurs méthodologies analytiques à l'analyse de spéciation des matières premières renouvelables et des fractions de pétrole lourd. Des techniques de séparation telles que la chromatographie par perméation de gel (GPC) et la chromatographie en phase liquide supercritique (SFC) ont été combinées avec la détection élémentaire fournie par la spectrométrie de masse haute résolution à plasma à couplage inductif (ICP-MS), afin d'obtenir une empreinte digitale de ces espèces d’intérêt, basé sur leur volume hydrodynamique, présent dans les échantillons à matrices complexes.La combinaison de ces techniques de séparation avec l’ICP-MS n'a pas été une tâche facile. Cependant, afin de fournir à la plate-forme de chimie analytique de nouvelles solutions pour l'analyse de spéciation d'échantillons complexes (1), une alternative bon marché aux nébuliseurs à consommation totale actuelle, produite via l'impression 3D et dont le capillaire a été construit en PEEK, a été développé et validé pour l'analyse des éléments trace dans les matrices organiques via GPC-ICP-MS et (2) une nouvelle interface a été conçue et optimisée pour l'analyse des éléments trace via SFC-ICP-MS. Bien que des résultats très prometteurs aient été obtenus, de nouvelles expérimentations doivent être menées avec ces deux méthodologies afin de mieux comprendre les espèces inorganiques présentes dans les matières premières renouvelables et les bio-huiles.La distribution en taille des espèces de soufre, de nickel et de vanadium dans les fractions de résidus atmosphériques a été obtenue via des analyses GPC-ICP-HRMS afin de suivre et de comprendre leur évolution au cours de deux processus industriels importants destinés à convertir ces fractions de pétrole lourd en carburants de transport: l'hydrodémétallisation et l'hydrodésulfuration. En outre, les distributions de tailles des espèces contenant du phosphore, du sodium, du fer, du magnésium et du soufre dans les huiles de pyrolyse lignocellulosique et les charges d'acide gras ont également été obtenues, démontrant que des agrégats de haut poids moléculaire se forment dans ces échantillons complexes lorsqu'ils sont stockés.Des méthodologies alternatives pour l'analyse des matières premières renouvelables ont été testées. L'utilisation de la vaporisation électrothermique couplée à la spectroscopie d'émission optique à plasma à couplage inductif (ETV-ICP-MS) a fourni des résultats très prometteurs. Une méthodologie qui ne nécessite pas l'utilisation de gaz fréon-R12 a été optimisée et validée pour l'analyse totale de huit éléments trace dans des échantillons complexes. De plus, la répartition des espèces contenant des éléments trace tels que P, Na, Mg et Al entre autres, en fonction de leurs températures de vaporisation, a été obtenue<br>This thesis incorporates the application of several analytical methodologies to the speciation analysis of renewable feedstocks and petroleum heavy oil fractions. Separation techniques such as gel permeation chromatography (GPC) and supercritical fluid chromatography (SFC) have been combinedwith the elemental detection that inductively coupled plasma mass spectrometry (ICP-MS) provides to obtain a fingerprint of those species of interest, based on their hydrodynamic volume, present in samples with complex matrices. However, the combination of these separation techniques with ICP-MS was not an easy task.With the purpose of providing to the analytical chemistry platform with novel approaches for the speciation analysis of complex samples, two novel tools have been devised during this three-year’s project: (1) a cheap alternative to the current total consumption nebulisers, produced via 3D-printing and whose capillary has been built in PEEK, has been developed and validated for the analysis of trace elements in organic matrices via GPC-ICP-MS and (2) a novel interface has been designed and optimised for the trace element analysis via SFC-ICP-MS. Although very promising results have been obtained, further experiments must be carried out with these two methodologies to obtain a better understanding of the inorganic species present in renewable feedstocks and bio-oils.The size distribution of sulfur, nickel and vanadium species in atmospheric residue fractions has been obtained via GPC-ICP-HRMS analyses to track and understand their evolution during two important industrial processes that are destined to convert these heavy oils into transportation fuels: hydrodemetallization and hydrodesulfurization. Furthermore, the phosphorus-, sodium-, iron-, magnesium- and sulfur-containing species’ size distributions in lignocellulosic fast pyrolysis oils and fatty acid feedstocks have been also obtained, demonstrating that high-molecular aggregates are formed within these complex samples when they are stored.Alternative methodologies for the analysis of renewable feedstocks have been tested. The use of electrothermal vaporisation coupled to inductively coupled plasma optical emission spectroscopy (ETV-ICP-OES) has provided with highly promising results. A methodology that does not require the use of freon-R12 gas has been optimised and validated for the total analysis of eight trace elements in complex samples. Besides, the distribution of the species containing trace elements such as P, Na, Mg and Al among others, based on their vaporisation temperatures, has been obtained<br>Denne PhD afhandling anvender forskellige analytiske metoder til specieringsanalyse af vedvarende råmaterialer og petroleumstunge oliefraktioner. I afhandlingen anvendes separationsteknikker som gel permeations kromatografi (GPC) og superkritisk væskekromatografi (SFC) i kombination med detektion af elementer somved induktiv koblet plasma-højopløsningsmassespektrometri (ICP-MS). Metoderne anvendes til at måle det kemiske fingeraftryk af specier i komplekse matricer , baseret på speciernes hydrodynamiske volumen. Kombinationen af kromatografiske separationsteknikker med ICP-MS var ikke en let opgave.For at opnå en forbedre analyse af komplekse matricer blev der udviklet en række nye forbedrede metoder til specifikationsanalysen af komplekse prøver: (1) en billig alternativ til den nuværende ”total consumption nebuliser” blev udviklet og valideret til sporstof anlayse i organiske matricer via GPC-ICP-MS. Den nye nebuliser blev produceret ved 3D print af PEEK materiale; (2) et nyt interface blev designet og optimeret til sporelementanalyse ved SFC-ICP-MS. Selvom der er opnået meget lovende resultater, skal yderligere eksperimenter udføres med disse to metoder for at opnå en bedre forståelse af specierne som er tilstede i vedvarende råmaterialer og bioolier.Størrelsesfordelingen af svovl-, nikkel- og vanadiumspecier i atmosfæriske restfraktioner er opnået via GPC-ICP-HRMS-analyser for at spore og forstå deres udvikling under to vigtigeindustrielle processer, der er designet til at omdanne ukonventionelle olier til transportbrændstof: hydrodemetallization og afsvovling.Endvidere er størrelsesfordelingen af forfor-, natrium-, jern-, magnesium- og svovlholdige specier målt i lignocellulosiske pyrolyseolier og fedtsyreholdige-råmaterialer. Disse resultater viser, at der dannes højmolekylære aggregater i disse komplekse prøver, når de opbevares ved normale forhold.Alternative metoder til analyse af vedvarende råmaterialer er blevet testet. Der blev opnået lovende resultater ved anvendelsen af elektrotermisk fordampning koblet til induktivt koblet plasmaoptisk emissionsspektroskopi (ETV-ICP-OES). En ETV-ICP-OES metode som ikke kræver anvendelse af freon-12-gas, er blevet optimeret og valideret til analyse af summen af otte sporstoffer i komplekse prøver. Metoden blev anvendt til analyse af sammensætningen af P, Na, Mg og Al specier baseret bl.a. på deres fordampningstemperaturer

Herpes simplex virus type 1 (HSV-1) Immediate-early protein ICP0 is important for regulating the balance between lytic and latent infections. The RING finger domain of ICP0 acts as an E3 ubiquitin ligase, binding to E2-ubiquitin conjugating enzymes and target proteins, promoting their polyubiquitination and subsequent degradation. ICP0 localises to cellular nuclear sub-structures known as ND10 at early stages of infection, and the RING finger domain induces the degradation and dispersal of ND10 proteins, which form part of the cell's intrinsic antiviral defence mechanism. The RING finger domain of ICP0 consists of an alpha-helix, and this and the loop regions are involved in interactions with the E2 ubiquitin-conjugating enzymes UBE2D1 and UBE2E1. Previous work using an ICP0-inducible cell line system found a mutation (N151D) in ICP0's alpha-helix, which allowed complementation of an ICP0-null mutant virus plaque formation but caused a substantial defect in the induction of reactivation of quiescent HSV-1. This raised the possibility that the mechanisms controlling lytic infection and reactivation may be separable. The main focus of this study was to investigate the N151D mutation and other mutations located within the alpha-helix (including K144E and K144E/N151D) using an inducible ICP0 expression cell system and virus infection studies. The phenotypes of these alpha-helix mutants were characterised to investigate if complementation/lytic infection and reactivation involve differential activities of ICP0. Additionally, these alpha-helix mutants were analysed for their in vitro E3 ligase ability and ability to interact with components of the ubiquitin pathway, focusing on E2 ubiquitin-conjugating enzymes. The results from this study using the inducible ICP0 cell system confirmed previous results. The alpha-helix mutants had a greater defect during reactivation than complementing the plaque forming defect of an ICP0-null mutant virus, and this was more noticeable for the K144E mutant. The virus infection studies showed a greater correlation between the effects of the mutations on the degradation of ND10 proteins, plaque formation and replication at low multiplicity of infection. The defect of the K144E mutation was more profound than N151D in all the assays, and the activity of a double mutant including mutations at both K144 and N151 (KE/ND) was reduced to levels comparable with the RING finger deletion mutant. Infection with mutants K144E and KE/ND greatly reduced the efficiency of reactivation of quiescent HSV-1 even at multiplicities of infection where their lytic infection was not severely affected, whereas N151D showed an intermediate phenotype. Furthermore, this study showed that ICP0 has the potential to interact with multiple E2 ubiquitin-conjugating enzymes, and the alpha-helix mutations may affect these interactions. Further investigation will be required to examine the roles that these E2 ubiquitin-conjugating enzymes play during HSV-1 infection. The data in this study indicate that there is no strong evidence to suggest that ICP0 utilises differential activities of its RING finger to mediate reactivation and the stimulation of lytic infection, despite the likely dissimilar nature of the viral chromatin structure in the two situations. These findings, however, provide an insight into the biological importance of the RING finger alpha-helix of ICP0 during the course HSV-1 infection and especially during reactivation from quiescence. In addition, motifs present within ICP0 that may be involved in interactions with other cellular proteins were analysed. These included the PPEYPTAP motif present within retroviral Gag proteins, the SIAH-1 interaction motif and residue T67 (which are all involved in interactions with cellular E3 ubiquitin ligases), and the CoREST binding region. Furthermore, a region of homology between alphaherpesvirus ICP0 proteins downstream of the RING finger domain, which had not previously been investigated in detail, was studied. These studies indicated that the region downstream of the RING finger domain (residues 211-222) may contribute to ICP0's activity, but no major role was detected for the other motifs studied.

Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências Físicas e Matemáticas, Programa de Pós-Graduação em Química, Florianópolis, 2016.<br>Made available in DSpace on 2016-05-24T17:56:31Z (GMT). No. of bitstreams: 1 338839.pdf: 8124296 bytes, checksum: c48b6b9f912908587f2d2857a2fea817 (MD5) Previous issue date: 2016<br>This work presents new approaches for halogen determination in a variety of samples using inductively coupled plasma - mass spectrometry (ICP-MS) and for isotope ratio measurements by multicollector - inductively coupled plasma - mass spectrometry (MC-ICP-MS) and application of the methods developed to real environmental cases. Four methods for solid sampling (SS) analysis by ICP-MS, three using electrothermal vaporization - inductively coupled plasma - mass spectrometry (ETV-ICP-MS) and one using laser ablation - inductively coupled plasma - mass spectrometry (LA-ICP-MS), and two methods for isotopic analysis by MC-ICP-MS, one for Br and another for Cl in sea water, were developed. The methods were applied for studying samples from real study cases, providing significant results with respect to environmental processes. For all three methods using SS-ETV-ICP-MS, the solid samples were directly weighed into graphite "cups" that were subsequently inserted into the graphite furnace, and the instrumental parameters were optimized for high sensitivity and efficient matrix removal. Chlorine determination in biological samples could be carried out using aqueous standard solutions, when using pre-dried modifiers (Pd + Nd or Pd + Ca) or using solid certified reference material (CRM), accompanied with or without the same pre-dried, achieving a limit of quantification (LOQ) of 5 ?g g-1. For Br and Cl determination in coal samples, Cl was accurately determined using calibration against solid standards, whereas Br could also be quantified adequately by using calibration against aqueous standard solutions, both using pre-dried modifiers (Pd + Ca), LOQs of 0.03 ?g g-1 for Br and 7 ?g g-1 for Cl were achieved. F, Cl, Br and I were determined in particulate matter, F was determined via high resolution - continuum source molecular absorption spectrometry (HR-CS MAS) for monitoring the CaF molecule, while Cl, Br and I were determined via SS-ETV-ICP-MS. This method allowed the quantification of the halogens in 14 PM10 samples collected in a Northeastern coastal city in Brazil. The results demonstrated variations of the halogen contents according to meteorological conditions, particularly related to rainfall, humidity and sunlight irradiation. Bromine determination in polymer samples was accomplished via LA-ICP-MS after the optimization of the operational parameters for high sensitivity. Under optimized conditions, it was possible to accurately determine Br in 5 different certified polymer reference materials and 5 real polymer samples by external calibration using different certified materials containing different concentrations of Br and by external calibration against a single certified material monitoring 12C+ as internal standard. The LOQ obtained was 110 ?g g-1 of Br. Bromine and Cl isotopic analysis in seawater via MC-ICP-MS was proven feasible, operated in high mass resolution and by decreasing the memory effect using 5 mmol L-1 of NH4OH in sample, standard and wash solutions. Optimal analyte concentrations were = 3 mg L-1 for Br and = 70 mg L-1 for Cl. The major cation load of seawater was removed via cation exchange chromatography (Dowex 50WX8 resin). In the case of Br, evaporation of the samples at 90°C permitted analyte preconcentration without Br loss or isotope fractionation. Mass discrimination was corrected for by external correction in a sample-standard bracketing approach for both elements. Sr, Ge and Se were also tested as potential internal standards for Br isotopic analysis but provided no advantage. Both methods demonstrated high precision and accuracy based on the comparison of experimental values with certified and literature values. The methods were applied within the context of an environmental study of Br and Cl in sea ice collected during the Sea Ice Physics and Ecosystem eXperiment 2012 voyage at different depths and locations. The concentration of these elements in the samples ranged from 700 to 31000 ?g L-1 for Br and from 200 mg L-1 to 8000 mg L-1 for Cl, and a relation between the concentrations and the corresponding ?81Br and ?37Cl values was found. Lower concentrations and ???values were observed for sea ice collected at greater depths and are probably related to desalinization processes.<br><br>Resumo : Os halogênios são um grupo de elementos que apresentam diversas particularidades, tornando-os muito importantes para diversos propósitos. No entanto, esses elementos apresentam elevado grau de toxicidade quando ingeridos ou inalados, e são considerados perigosos quando presentes no meio ambiente, devido principalmente ao fato de poderem reagir com moléculas de O3, promovendo a destruição da camada de ozônio. Considerando a alta aplicabilidade dos halogênios e seus efeitos adversos ao ambiente e em sistemas biológicos, faz-se necessário o estabelecimento de métodos sensíveis, com exatidão e precisão, para a sua determinação. Técnicas como eletrodos de íon seletivos, cromatografia de íons, análise por ativação de nêutrons instrumental, espectroscopia de fluorescência por raios-X, entre outros, foram propostos e aplicados com sucesso para analise de halogêneos em diversas matrizes, no entanto, em alguns casos, morosas etapas de preparo de amostras são necessárias, além de algumas das técnicas apresentarem limitações para analise multielementar, baixa sensibilidade, baixa frequência analítica, incidência de interferências e curta faixa linear para quantificação. Além de problemas para sua quantificação, a medida de razão isotópica de halogênios ainda é um desafio. Algumas técnicas têm sido aplicadas para este propósito como a espectrometria de massas de razão isotópica e espectrometria de massas por ionização química, entretanto, normalmente apresentam baixa precisão além de apresentarem muitos dos problemas apresentados para quantificação. Desta forma, o objetivo geral deste trabalho é apresentar propostas a fim de solucionar os problemas enfrentados para análise de halogênios por espectrometria de massas por plasma indutivamente acoplado (ICP-MS) e analise de razões isotópicas por multicoletor (MC)-ICP-MS, aplicando os métodos desenvolvidos para o estudo de casos ambientais reais. Uma breve introdução abordando os conceitos básicos sobre a importância dos halogênios, uma visão geral sobre funcionamento de equipamentos ICP-MS, determinação e análise isotópica de halogênios por ICP-MS é apresentada no Capítulo 1 o qual é seguindo pelos Capítulos 2, 3 e 4 onde se apresentam novas propostas para determinação de halogênios por meio da analise direta de sólidos utilizando vaporização eletrotérmica (SS-ETV)-ICP-MS e aplicação dos métodos propostos a analise de amostras biológicas, minerais e ambientais em diferentes estudos. O Capítulo 5 apresenta o desenvolvimento de um método simples para determinação direta de Br em amostras de polímeros por ablação a laser (LA)-ICP-MS, enquanto que os Capítulos 6, 7 e 8 abordam o desenvolvimento de métodos para medida da razão isotópica de halogênios em água do mar e amostras de gelo marinho por MC-ICP-MS. No Capítulo 2, uma nova metodologia para a determinação de Cl em amostras biológicas e botânicas usando SS-ETV-ICP-MS é apresentada. As amostras sólidas foram pesadas diretamente em plataformas de grafite (copos de grafite da técnica cup-in-tube) e inseridas no forno de grafite. Os parâmetros de potencial de rádio frequência (RF) e a vazão de gás carreador foram otimizados em 1300 W e 0,7 L min-1, respectivamente. Padrões aquosos foram utilizados para a obtenção da curva de calibração com o auxílio de modificadores pré-secos (Pd + Nd ou Pd + Ca) ou utilizando um material de referencia certificado (CRM) sólido com os mesmos modificadores pré-secos ou sem a utilização de modificadores. O limite de quantificação (LOQ) obtido foi 5 ?g g-1 sob condições otimizadas. A concentração de Cl foi determinada em cinco amostras de referência certificadas, com concentrações certificados para Cl, além de três amostras de referência certificados com concentrações certificadas para Cl indisponíveis, neste último caso, os resultados foram comparados àqueles obtidos utilizando espectrometria de absorção molecular de alta resolução com fonte contínua (HR-CS MAS). As concentrações obtidas demonstraram-se em acordo, a um nível de confiança estatística de 95%, com os valores certificados ou de referência.O Capítulo 3 apresenta um novo método para a determinação direta e simultânea Br e Cl em amostras de carvão utilizando SS-ETV-ICP-MS. O processo não requer pré-tratamento de amostras e necessita de pequenas alíquotas de massa de amostra (cerca de 0,5 mg). Todos os parâmetros operacionais, incluindo vazão de gás carreador e potencial de RF, foram otimizados para o máximo de sensibilidade. O uso de modificadores/ carreadores de aerossóis (Pd, Pd + Al e Pd + Ca) foi avaliado e a combinação de Pd e Ca foi escolhida, permitindo a adoção das temperaturas de pirólise e vaporização de 700 oC e 1900 oC, respectivamente. Cloro foi determinado com o auxilio de calibração utilizando padrões sólidos, enquanto Br foi determinado tanto por calibração aquosa quanto utilizando CRM sólidos. Os LOQs obtidos foram de 0,03 ?g g-1 para Br e 7 ?g g-1 para Cl, interferências espectrais não foram observadas.No Capítulo 4 foi avaliada a viabilidade da análise direta de sólidos por HR-CS MAS para a determinação de F e ETV-ICP-MS para determinação simultânea de Cl, Br e I em material particulado inalável no ar (PM10), coletados na região metropolitana de Aracaju, Sergipe, Brasil. As análises de F por HR-CS MAS foram realizadas monitorando a molécula de CaF que foi gerada a altas temperaturas na câmara de grafite após a adição de cálcio em uma relação Ca/ F de 35. As análises por ETV-ICP-MS foram realizadas utilizando Ca como modificador químico/ carreador de aerossol com a utilização concomitante de Pd como modificador permanente, a fim de evitar perdas de Cl, Br e I durante a etapa de pirólise. A abordagem de analise direta de sólidos resultou em LOQs adequados para a determinação de halogêneos em PM10, usando a calibração por adição de analito ou calibração utilizando um CRM solido. O método permitiu a quantificação dos halogênios em 14 PM10 coletadas em uma cidade costeira do nordeste do Brasil. Os resultados demonstraram variações de teor de halogênios de acordo com as condições meteorológicas, principalmente relacionados a chuvas, umidade e irradiação solar. O Capítulo 5 foi destinado à avaliação da utilização da LA-ICP-MS para análise de Br em amostras de polímeros. Os parâmetros operacionais do LA-ICP-MS, incluindo a vazão de gás carreador, potencial de RF, tamanho da cratera de ablação e frequência do laser foram otimizados para o máximo de sensibilidade. Os valores otimizados foram 0,6 L min-1 para vazão de gás carreador (He), 950 W de potencial de RF, 120 ?m de tamanho da cratera de ablação e 15 Hz de frequência do laser. Sob condições otimizadas foi possível determinar, com exatidão, Br em 5 amostras certificadas de polímeros e 5 amostras reais de polímeros obtidas em estabelecimentos locais em Ghent, Bélgica por calibração externa utilizando CRMs contendo diferentes concentrações de Br e por calibração externa utilizando apenas um CRM monitorando 12C+ como padrão interno. O LOQ obtido foi de 110 ?g g-1 para Br.O Capítulo 6 apresenta um método simples para medida da razão isotópica de Br em água do mar por MC-ICP-MS, utilizando nebulização pneumática para introdução da amostra. Os sinais dos isótopos de Br+ foram medidos livre de interferências utilizando alta resolução. O efeitos de memória para Br foi diminuído utilizando 5 mmol L-1 NH4OH como solução de limpeza entre as medidas. O conteúdo catiônico da água do mar foi removido por cromatografia catiônica utilizando uma resina Dowex 50WX8. Pré-concentração das amostras foi obtida por evaporação a 90°C, sem perda ou fraccionamento isotópico de Br. Discriminação de massas foi corrigida por correção externa utilizando bracketing, embora Sr, Ge e Se foram testados como potenciais padrões internos. Os valores 81Br/ 79Br obtidos para os materiais de referência isotópicos (NaBr) NIST (material de referencia padrão) SRM 977 e (água do mar) IRMM BCR-403 demonstraram estar de acordo com os valores da literatura.No Capítulo 7, a medida da razão isotópica de Cl em água do mar por MC-ICP-MS através de nebulização pneumática tradicional foi realizada utilizando, i) alta resolução de massa (potencial de resolução de 10.000) para resolver interferências espectrais, ii) 5 mmol L-1 NH4OH como solução de limpeza a fim de diminuir o efeito de memória e iii) uma concentração de Cl de = 70 mg L-1. A carga catiônica da água do mar e de sais de cloreto (NaCl, KCl) foi eficientemente removida sem afetar a composição isotópica original da Cl através de cromatografia catiônica utilizando resina de troca iônica Dowex 50WX8. O método desenvolvido demonstrou alta exatidão e precisão, atestadas pela medição da razão isotópica 37Cl/ 35Cl na amostra CRM NIST 975a (valor obtido de 0,319765 ± 0,000022, em comparação com um valor de referência de 0,319768 ± 0,000187 a uma precisão de ~ 0,007%, desvio padrão relativo, n = 3). Além disso, o valor???37Cl (baseado no padrão de cloro em água do mar, SMOC) foi determinado para cinco padrões diferentes que variaram de -0,54 a + 0,89 ?. O Capítulo 8 apresenta um estudo ambiental de Br e Cl em gelo marinho coletados durante a expedição Sea Ice Physics and Ecosystem eXperiment 2012, em diferentes profundidades e locais. Todas as medições de razão isotópicas de Br e Cl foram realizadas de acordo com os métodos apresentados no Capítulo 6 e 7. A concentração destes elementos variou de 700 para 31000 ?g L -1 para Br e de 200 para 8000 mg L-1 para Cl, sendo que as menores concentrações foram relacionados com o gelo coletado em maiores profundidades, estando a diminuição da concentração de Br e Cl provavelmente relacionadas a processos de dessalinização. Os valores de ?81Br e ??37Cl apresentaram relação linear com a suas concentrações, sugerindo que o processo de dessalinização desempenha um papel no fraccionamento isotópico no gelo do mar.

a b s t r a c t A slurry nebulisation technique was applied for elemental analysis of bituminous coals SARM 18, SARM 19 and four coals from three different seams in Witbank, South Africa, by inductively coupled plasma optical emission spectroscopy (ICP-OES). Major elements (Al, Ca, Fe, Mg, S, Si and Ti) and trace elements (Ba, Cr, Mn, Ni, Sr, V, Zn and Zr) in coal were determined. Various slurry preparations were evaluated using two dispersants (glycerol and Triton X-100) and by varying the concentration of dispersants, between 0.1% and 1.0% (v/v). The effect of initially solubilising the ground coal in N,N-dimethylformamide (DMF) was investigated by varying the volume of DMF added. The effect of wet grinding with DMF was investigated. Wet grinding with DMF was shown to drastically reduce particle sizes (50.0% < 0.28 lm and 90.0% < 6.17 lm) as compared to dry grinding (50.0% < 5.25 lm and 90.0% < 11.1 lm). The reduced particle sizes and increased transport efficiency of the coal slurries led to improved analytical recoveries of elements in the reference coal, SARM 18. The best analytical recoveries for all elements were achieved using 0.1% Triton X-100 with 10.0% DMF. Results obtained by ICP-OES after wet grinding of the coal with DMF, using 0.1% Triton X-100, also gave excellent recoveries (Al, 100%; Ca, 103%; Cr, 106%; Fe, 102%; Mg, 100%; Mn, 104%; Ni, 109%; Si, 102%; Ti, 95.0%; and V, 108%). The results obtained with 10.0% DMF and 0.1% Triton X-100 were in agreement with certified values for all selected elements according to paired t-test at the 95.0% confidence level. Selected elements (Al, Ca, Fe, Mg, Mn, Si, Ti and V) were also analysed with X-ray fluorescence for comparison with results obtained from ICP-OES. Analysis by ICP-OES of microwave digested coal was also carried out. It is suggested that the DMF slurry technique could be used for routine analysis of bituminous coals.

Laser Ablation - Inductively Coupled Plasma - Mass Spectrometry (LA-ICP-MS) is a powerful analytical technique for the direct elemental analysis of solid samples, with spatial resolution down to a few microns However, calibration remains the limiting factor in obtaining quantitative analysis by LA-ICP-MS for a wide range of sample types. No universal method exists as yet and the ones that are currently used tend to employ matrix-matched solid standards Matrix-matched solid standards are not available for many types of sample, such as polymers, biological materials, fluid inclusions, etc The need for a universal method of calibration that involves standards that are easy to prepare and suitable for any type of sample is required. Additional to matrix-matching, internal standards are widely used in LA-ICP-MS for quantitative analyses The internal standard compensates for the different ablation yields from the sample and the standard and for the laser shot to shot variation. Given that the use of an internal standard is required to obtain reliable results, the need for matrix-matching might be regarded as questionable This project has focused on the development and application of a new method of calibration for LA-ICP-MS. It involves the use of aqueous standards whose absorption characteristics are modified by the addition of a chromophore to the solution. Additives were selected for ablation with KrF excimer, and Nd.YAG lasers The influence of the additive concentration on the ablation yield was investigated for different laser energies. Response curves were obtained showing that as the additive concentration was increased, less energy was required to ablate the modified standard solutions efficiently. A general procedure was then defined for the preparation and use of the modified standard solutions for a given sample. The new method of calibration was used for the quantitative analysis of different sample types· low density polyethylene (LDPE), polyketone (PK), polyethylene thin film as well as gels contained in the thin film, and stainless steel. Investigations were carried out on the mechanism of ablation of the modified standard solutions. It appeared that the ablation proceeded by a three-step process leading ultimately to nebulisation of the bulk liquid.

The application of inductively-coupled plasma (ICP) spectrometry for the analysis of solutions and slurries is reviewed. The critical parameters which affect analytical performance are identified and methods for the optimisation of the ICP for such applications demonstrated. Particle size of the suspended sample is shown to be the most important factor in the analysis of slurry samples. It is demonstrated that only particles less than 8 um in diameter reach the plasma even when the maximal diameter injector tube (3 mm i.d.) is used. Accordingly various methods for the reduction of particle size have been investigated and milling shown to be the preferable approach. A low cost method using blown zirconia spheres in a screw-cap plastic bottle agitated on a flask shaker was developed. Using this method it proved possible to analyse a wide variety of solid samples using slurry atomisation using both ICP- atomic emission spectrometry (ICP-AES) and ICP-mass spectrometry (ICP-MS) with aqueous calibration. Results are presented for the elemental analysis of certified reference material (CRM) soils, catalyst samples, a zeolite, titanium dioxide, P.T.F.E. powder, and unfiltered natural waters by slurry atomisation ICP-AES. Comparison by other techniques showed excellent accuracy for major, minor and trace elements and equivalent precision to solution analysis. The CRM soils, catalysts and the zeolite were also analysed by ICP-MS using slurry atomisation with similar success and enhanced accuracy at the trace level. Aluminium proved to be an exception and generally low recoveries (80-90%) were observed for this element using slurry atomisation. Finally the uses of the simplex optimisation algorithm to improve analytical performance, particularly in ICP-AES, is discussed. A computer program to facilitate the use of simplex optimisation for a variety of instrumentation was written and its use in three different analytical techniques demonstrated. The necessary hardware and software modifications to a commercially available ICP spectrometer to enable automated simplex optimisation are described. The prospects for such intelligent self-optimising instrumentation are discussed as is the potential extension of the application of slurry analysis by ICP-AES and ICP-MS.

The need for elemental analysis of biological matrices such as bone, teeth, and plant matter for sourcing purposes has emerged within the forensic and geochemical laboratories. Trace elemental analyses for the comparison of aterials such as glass by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS has been shown to offer a high degree of discrimination between different manufacturing sources. Unit resolution ICP-MS instruments may suffer from some polyatomic interferences including 40Ar16O+, 40Ar16O1H+, and 40Ca16O+ that affect iron measurement at trace levels. Iron is an important element in the analysis of glass and also of interest for the analysis of several biological matrices. A comparison of the nalytical performance of two different ICP-MS systems for iron analysis in glass for determining the method detection limits (MDLs), accuracy, and precision of the measurement is presented. Acid digestion and laser ablation methods are also compared. Iron polyatomic interferences were reduced or resolved by using dynamic reaction cell and high resolution ICP-MS. MDLs as low as 0.03 ìg g-1 and 0.14 ìg g-1 for laser ablation and solution based analyses respectively were achieved. The use of helium as a carrier gas demonstrated improvement in the detection limits of both iron isotopes (56Fe and 57Fe) in medium resolution for the HR-ICP-MS and with a dynamic reaction cell (DRC) coupled to a quadrupole ICP-MS system. The development and application of robust analytical methods for the quantification of trace elements in biological matrices has lead to a better understanding of the potential utility of these measurements in forensic chemical analyses. Standard reference materials (SRMs) were used in the development of an analytical method using HR-ICP-MS and LA-HR-ICP-MS that was subsequently applied on the analysis of real samples. Bone, teeth and ashed marijuana samples were analyzed with the developed method. Elemental analysis of bone samples from 12 different individuals provided discrimination between individuals, when femur and humerus bones were considered separately. Discrimination of 14 teeth samples based on elemental composition was achieved with the exception of one case where samples from the same individual were not associated with each other. The discrimination of 49 different ashed plant (cannabis)samples was achieved using the developed method.

This thesis details the structural and elemental analysis of the III-V quaternary InGaAsN, and subsequent post growth plasma processing of the alloy. The aim of the work was to investigate the varying properties of the material with respect to the CBE growth conditions during deposition. Primarily this was with the objective of producing 1.3J.I.IIl emitting material for quantum well laser diodes. However the large scope of this complex alloy in terms of band structure and lattice variability will make it suitable for a range of applications provided high structural quality can be maintained. Photoluminescent emission with near 1.3J.1m wavelength has been demonstrated for both lattice-matched and compressively strained variants of InGaAsN/GaAs in quantum well form. Homogeneous QW material has been produced for various element fractions with high structural quality through close monitoring of the N and In concentrations. However a three-dimensional growth pattern becomes dominant when increased band gap tailoring is attempted, this is particularly evident when raised nitrogen levels are employed. The miscibility gap introduced by this element disrupts growth surface bonding conditions resulting in a preferential phase segregated defective material. Surface nitridation prior to InGaAsN growth can induce quantum dot or island formation directly on the GaAs buffer surface. Near 1.3J.1mwavelength emission has also been achieved from a quantum dot form of the alloy. A high level of sensitivity in the structural quality of the material with respect to substrate temperature during growth was also demonstrated, lower temperature giving the best results. Poor optical properties can be improved with the application of a post growth high temperature anneal process .Thin film InGaAsN/GaAs has only been produced homogeneously up to a layer thickness of -50nm, and this was achieved using a compressively strained form of the alloy. Lattice-matched material grows in a very disordered and defective manner, this is thought to be due to the raised N fraction required. Higher N containing InGaAsN/GaAs compounds, and surface pre-nitridation, lead to the development of completely phase-segregated epilayer. A cellular-like microstructure becomes dominant consisting of InGaAs volumes encompassed by a highly N-rich Ga(As)N interlayer. Three-dimensional growth is thought to originate from the preferential grouping of the component elements on the various facets of the growth surface, which can be affected by In and N concentrations and growth temperature. Production of high structural and optical quality InGaAsN/GaAs requires the use of non-optimal growth conditions, which may prove problematic particularly in CBE. Material quality still requires refinement, however InGaAsN/GaAs alloys look very promising for a range of optoelectronic devices. ICP processing of thin film InGaAsN/GaAs has shown to be very sensitive to the alloy microstructure for both SiC4 and Cl-.Ar etch chemistries. However highly anisotropic etches at high etch rates with minimal surface damage have been demonstrated. The higher power ion-assisted set-up has proven more effective than the more chemically assisted material removal in all cases. Alloys with both increased N or In give higher etch rates, and in non-optimised conditions In redeposition may become problematic for the chemistries investigated. ICP etching has indicated itself to be a very promising process for III-V device production, but in the case ofInGaAsN/GaAs quality will be dependent on the compound itself. Thin film InGaAsN/GaAs has only been produced homogeneously up to a layer thickness of -50nm, and this was achieved using a compressively strained form of the alloy. Lattice-matched material grows in a very disordered and defective manner, this is thought to be due to the raised N fraction required. Higher N containing InGaAsN/GaAs compounds, and surface pre-nitridation, lead to the development of completely phase-segregated epilayer. A cellular-like microstructure becomes dominant consisting of InGaAs volumes encompassed by a highly N-rich Ga(As)N interlayer. Three-dimensional growth is thought to originate from the preferential grouping of the component elements on the various facets of the growth surface, which can be affected by In and N concentrations and growth temperature. Production of high structural and optical quality InGaAsN/GaAs requires the use of non-optimal growth conditions, which may prove problematic particularly in CBE. Material quality still requires refinement, however InGaAsN/GaAs alloys look very promising for a range of optoelectronic devices. ICP processing of thin film InGaAsN/GaAs has shown to be very sensitive to the alloy microstructure for both SiC4 and Cl-.Ar etch chemistries. However highly anisotropic etches at high etch rates with minimal surface damage have been demonstrated. The higher power ion-assisted set-up has proven more effective than the more chemically assisted material removal in all cases. Alloys with both increased N or In give higher etch rates, and in non-optimised conditions In redeposition may become problematic for the chemistries investigated. ICP etching has indicated itself to be a very promising process for III-V device production, but in the case ofInGaAsN/GaAs quality will be dependent on the compound itself. This thesis describes an account of the research that was undertaken with the supervision of Dr. P. Chalker and Dr. T. J. Bullough in the Department Engineering, The University of Liverpool between the period of October 1999 and September 2003. All of the research is original and has not been submitted for degree from this or any other university. Where applicable the work and results of other people have been included and due acknowledgement has been made. A complete and extensive list of references is presented at the end of this thesis.

La faïence est une céramique caractérisée par son revêtement vitreux blanc opaque, grâce à l'adjonction d'oxyde d'étain ; sur ce fond on peut apposer les décors polychromes. Résultant d'une technologie abbaside (VIIIe siècle), elle connait son apogée en France au XVIIIe siècle. Les précédentes études menées sur la faïence moderne ont mis en évidence la nécessité de procéder à une approche pluridisciplinaire pour appréhender ce matériau complexe, ses techniques de fabrication, et cerner les enjeux de sa production. Ce travail de recherche s'inscrit dans la continuité pour s'élargir aux productions faïencières du Sud Ouest de la France quelques peu délaissées du point de vue archéométrique. La manufacture Babut, première faïencerie établie à Bergerac, fut sélectionnée dans ce but. La production perdure sur cinquante ans environ, jusqu'à la Révolution Française.En prenant en considération ces observations, cette thèse a permis tout d'abord d'identifier la production du point de vue des matériaux et des techniques, de mettre en place un référentiel géochimique, ainsi qu'établir un corpus stylistique de base pour cette manufacture. Ensuite l'étude a porté sur l'évaluation du potentiel de méthodes d'analyses non destructives pour l'attribution de provenance directe à partir de la surface des glaçures. Et enfin ce travail a permis d'examiner la place de la faïence bergeracoise et de sa production au sein du tissu industriel régional, et les replacer dans le contexte plus général de la production faïencière française à l'aube de la Révolution industrielle.

A complete description of the origin, transport, fate, and effects of the atmospheric particulate matter (PM) in the polar regions is not yet available. Pb is a toxic element that is introduced into the environment in large amounts by anthropic activities, but it is also a useful atmospheric tracer because its isotopic composition is closely related to its geographic origin. Therefore, Pb isotopic analysis of PM10 collected from East Antarctica (Dome C, East Antarctic Plateau) and the Arctic (Svalbard Islands) has been performed, for sources recognition of the atmospheric Pb that reaches these remote areas. PM10 was directly collected from the atmosphere by air filtration upon PTFE membrane filters. In Antarctica, snow samples were collected from snow pits to evaluate the temporal variation of PM (provenience, composition) during the last decades. The information about the provenience of Pb was compared with that obtained from the atmospheric circulation models (back-trajectory analysis), allowing an overview of the long-range atmospheric transport of PM10 toward the Arctic and Antarctica. However, a better interpretation of the actual situation is only possible by considering different types of tracers, such as the isotopic composition of Sr, linked to the mineral dust input, and the elemental characterization of the PM10. Therefore, new methods for the elemental analysis of snow by ICP-AES, and the direct Sr isotopic analysis by ICP-MS/MS have been developed. These methods will be applied to the snow and PM10 samples which are still collected from the same sites, to extend the existing data set, and from additional sampling sites to improve our knowledge of the spatial variability of PM transport and deposition.

The analytical performance of laser ablation (LA) for multielemental determination of geological and biological samples has been investigated. In the present study, LA has been used for sample introduction in inductively coupled plasma sector field mass spectrometry (ICP-SFMS). Although LA can provide semi-quantitative results rapidly and easily, the calibration process still remains the "Achilles heel" of the technique. The major goal of this study has been to investigate the capabilities of LA-ICP-SFMS for qualitative and quantitative analysis of various solid materials. LA was used for analyses of coal were calibration was performed by using coal powder doped with analyte elements. This was done by adding solution standards (including analyte and internal standard elements) to the coal, drying and finally homogenising, followed by pressing tablets. LA results were compared with data obtained by conventional solution nebulisation (SN) after preparation of coal samples using microwave (MW) digestion or fusion. In spite of a relatively poor agreement for elements such as As, Se, Sn, Re, Te, and Tl, accuracy obtained with LA in the present study is otherwise generally superior to previously reported data for LA and slurry nebulisation. For about 50 elements, results obtained with LA fall within 20% of those obtained by SN. The study shows the potential of LA quantification, based on solution-doped powders. However, the necessity of sample grinding and homogenising results in loss of spatial distribution information and makes the approach more vulnerable to sample contamination. The possibilities of sulphide minerals analysis by ICP-SFMS have been investigated. Seven elements (Co, Fe, Cd, Ag, Mn, Cu and S) have been quantitatively determined in sphalerite samples from the Zinkgruvan mine, using Zn as internal standard (IS). A straightforward calibration procedure allows on-line correction for possible Fe impurities at percent levels. Consequently, the use of complimentary techniques for determination of actual Zn content in the samples is avoided. The LA-ICP-SFMS results were compared with data from conventional SN introduction of sample solutions following acid digestion. Good agreement was found between the methods. For homogeneously distributed elements the overall precision for LA was found to be better than 10% RSD. A method for total mineral dissolution of five sulphides (sphalerite, pyrite, galena, pyrrhotite and chalcopyrite) has been developed, followed by multielemental analysis by ICP-SFMS. By performing this mineral characterisation the intention was to determine whether the analysed bulk mineral samples could be used as in-house LA calibration standards. The use of LA was focused towards elucidating whether the observed deviations in results obtained by ICP-SFMS for the two reference material powders used were caused by sample inhomogeneity or by inefficient matrix dissolution. It was found that the reference materials showed lack of accuracy in recommended concentrations for many trace and ultra trace elements, as well as possible inhomogeneity when using 50 mg sample amounts. The sulphide minerals studied appears to be suitable as matrix matched calibration standards for the determination of about 20 trace and ultra trace elements by LA. Laser ablation was also used for analysing element to sulphur ratios in washed human nails. The element ratios were then used to display the effectiveness of the applied washing method applied prior to MW digestion and analysis by ICP-SFMS. Based on the LA analysis, it was found that, even after the applied nail washing procedure, many elements are enriched in the surface of the nail.<br>Godkänd; 2000; 20070317 (ysko)

The present PhD is focused on the development of new analytical methods based on ICP techniques to carry out the elemental and isotopic analysis of bioethanol samples and other specimens taken along the bioethanol production process. The total sample consumption system, so-called hTISIS, has been used as sample introduction system in ICP-OES for the quantification of major and minor metals, and ICP-MS for the determination of trace metals. The hTISIS has also been successfully set up to carry out the lead isotopic analysis of bioethanol samples. Additionally, metals found in bioethanol have been monitored along the production process of this biofuel to identify the origin of these metals. Finally, volatile organic compounds have been determined in different bioethanol samples to perform the characterization of the matrices and their effect on the accuracy of the methods based on ICP techniques, developed in the present PhD for the elemental and isotopic analysis of these kind of samples.<br>La presente Tesis Doctoral se centra en el desarrollo de nuevos métodos de análisis basados en técnicas de ICP para llevar a cabo el análisis elemental e isotópico de muestras de bioetanol y muestras tomadas a lo largo del proceso de obtención de dicho biocombustible. Se ha empleado un sistema de consumo total de muestra, conocido como hTISIS, como sistema de introducción de muestras en ICP-OES para la cuantificación de metales mayoritarios y minoritarios, y en ICP-MS para la determinación de metales traza en bioetanol. El sistema hTISIS también se ha empleado con éxito para llevar a cabo el análisis isotópico de plomo en dichas muestras. Además, los metales encontrados en las muestras de bioetanol han sido monitorizados a lo largo del proceso de obtención del mismo para identificar el origen de dichos metales. Finalmente, se han determinado los compuestos volátiles presentes en diferentes muestras de bioetanol, con el objetivo de caracterizar las matrices y como estas pueden afectar a la exactitud de los métodos desarrollados, que emplean técnicas ICP para el análisis elemental e isotópico de este tipo de muestras.

Impact E/P copolymer (ICP) is produced using gas-phase polymerization catalysed by Ziegler-Natta catalysts. This material with its excellent mechanical properties is used in many industries, for example in automotive industry to produce bumpers or instrument panels. Its properties depend on chemical structure which was analysed using DSC, 13C NMR and GPC. It was used 6 different samples of ICP for studies, the chosen samples have different ratio between ethylene and propylene in their copolymer phase. The samples were fractionated using preparative TREF and solvent extraction to obtain fractions, which composition depends on elution temperature. Obtained fractions and original samples were subsequently analysed using above-mentioned methods.

Made available in DSpace on 2014-10-09T12:54:07Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:09:24Z (GMT). No. of bitstreams: 1 12435.pdf: 4820144 bytes, checksum: 0d8279d9b23571886f63adee62a8b6f4 (MD5)<br>Tese (Doutoramento)<br>IPEN/T<br>Instituto de Quimica, Universidade de Sao Paulo - IQ/USP

In this research, electrochemical methods are used to synthesize the inorganic fraction of bone, hydroxyapatite, for application in biological implants and as a calibration material for elemental analysis in human bone. Optimal conditions of electrochemically deposited uniform apatite coatings on stainless steel were investigated. Apatite is a ceramic with many different phases and compositions that have beneficial characteristics for biomedical applications. Of those phases hydroxyapatite (HA) is the most biocompatible and is the primary constituent of the inorganic material in bones. HA coatings on metals and metal alloys have the ability to bridge the growth between human tissues and implant interface, where the metal provides the strength and HA provides the needed bioactivity. The calcium apatites were electrochemically deposited using a modified simulated body fluid adjusted to pH 4-10, for 1-3 hours at varying temperature of 25-65°C while maintaining cathodic potentials of -1.0 to -1.5V. It was observed that the composition and morphology of HA coatings change during deposition by the concentration of counter ions in solution, pH, temperature, applied potential, and post-sintering. The coatings were characterized by powder x-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. The precipitated powders from the experiment were also characterized, with results showing similarities to biological apatite. There is a need for quantitative elemental analysis of calcified biological matrices such as bone and teeth; however there are no suitable calibration materials commercially available for quantitative analysis. Matrix-matched standards are electrochemically synthesized for LA-ICP-MS analysis of human bone. The synthetic bioapatite is produced via a hydrothermal electrochemical process using a simulated body fluid solution to form hydroxyapatite. Additional bioapatite standards are synthesized containing trace amounts of metals. The x-ray diffraction of the synthesized standards shows an increase in cell volume for the crystal structure from 0.534 to 0.542 nm3 with the substitution of metals into the crystal structure. The analyte concentration and recoveries for the synthesized standards and reference materials were determined by ICP-MS with % RSD below 6.3% and limits of detection below 1.2 ng/mL for trace metals. The electrochemically synthesized bioapatite was also compared to standard reference materials with X-ray diffraction, FTIR, and Raman spectroscopy. Optimum laser ablation parameters were determined for the standards and human bone. The synthesized standards were homogeneous and the reproducibility for the isotope concentrations determined by LA-ICP-MS was between 3-10 % compared to 10-35% for SRM 1486 Bone Meal and SRM 1486 Bone Ash. A quantitative method has been developed for 2D mapping using LA-ICP-MS and the matrix-matched standards of metal-doped biopaptite to characterize metal concentrations in human bone. Laser ablation parameters for the method are refined resulting in concentration (ug/g) contour map measurements for each isotope measured in the human bone. Essential and non-essential metals, Al, Ca, Cu, Fe, Pb, and Zn are quantitatively mapped using these parameters. Limit of detection for the metals in the bone range from 0.001 to 0.08 ug/g. The LA-ICP-MS analysis method developed proves to be a straightforward and simple method for quantitative analysis of human bone.

Arsenic (As) is one of the common cancers causing contaminant in groundwater of West Bengal, India along with other regions of the world. Scientists believe that As contamination in groundwater of these region are because of the reductive dissolution of iron oxyhydroxide and the oxidation of organic matter. However, our research shows that a combination of carbonate mineral dissolution and the reduction of iron oxyhydroxides accounts for the high As concentration in groundwater. Thus the people of this region are exposed daily to high levels of As through various pathways. Our study on saliva shows that this biofluid is a good biomarker of As exposure. Moreover, by measuring the various forms of As in saliva, individual susceptibility to arsenic related diseases can be understood. Lastly, we propose nano Zero Valent iron doped onto montmorillonite as an effective material to reduce high levels of As in water quickly and efficiently<br>L'arsènic (As) és un dels contaminants cancerígens més comuns en les aigües subterrànies de Bengala Occidental, Índia, així com d’altres regions. Els científics creuen que la contaminació en arsènic en l'aigua subterrània d'aquesta regió és deguda a la dissolució reductiva dels oxihidròxids de ferro i a l'oxidació de la matèria orgànica. No obstant, la nostra investigació mostra que una combinació de la dissolució mineral de carbonat i la reducció dels oxihidròxids de ferro en són la causa. Com a conseqüència la població d'aquesta regió estan exposats a nivells alts d'As. El nostre estudi mostra que la saliva és un bon biomarcador d'exposició a l’arsènic. A més, mitjançant la determinació de l’especiació d’As en saliva es pot comprendre la susceptibilitat individual a malalties relacionades amb aquest element. Finalment, proposem la utilització de montmorillonita dopada amb nanopartícules de ferro metàl·lic com un material eficaç per reduir els alts nivells d'As en l'aigua

Chemical data obtained through LA-ICP-MS, EPMA and XRF analysis have been used to investigate the potential for provenancing archaeological.artefacts. By combining chemical analysis with multivariate statistical analysis (pCA and cluster analysis) a more robust and objective method of classification and provenancing can be obtained. Modem glass bottles were used as an analogue for Islamic Bahraini glass samples, to test the application ofXRF analysis. For the modem glass samples which were homogeneous, with the chemistry being tightly controlled during manufacture and were free from alteration by weathering, an accurate method of provenancing was obtained. The colour of the glass was found to be a confounding factor. By restricting statistical analysis to a single colour of sample, a wide range of bottles from around the world were accurately grouped into the region where they were manufactured. Applying the same methods to the Islamic Bahraini glass it was found that the amount of weathering was a major confounding factor, as was the colour of the sample. When performing PCA and cluster analysis it was found that samples clustered together depending on their degree of weathering or how well weathering products had been removed prior to analysis. The size of sample for XRF was found to have an effect on the accuracy of the analysis, caused by x-ray attenuation within the sample and therefore requiring a ZAP like correction to be made to major and minor elemental data. No effect was seen when performing PCA and cluster analysis. Variations in the amounts of MgO and K20 present indicate that plant ashes were used as the soda source and not natron. There may be slight differences in the plants or the parts of plants used in manufacture. Ah03 contents also indicate differences in the silica source but neither of these appear to be related to the period of time or location where the samples were found. It is possible that raw glass was brought to Bahrain for re-working or that finished items were traded from elsewhere as no evidence was found in the samples for primary glass production (frit). The analysis of carnelian beads from India and Mali by LA-ICP-MS was found to be difficult. Although the heterogeneity within a carnelian bead was found to be much less than that seen in samples of agate, the chemical variations within in a sample was still large and would outweigh any differences between sources.

Analytical methods were developed and validated for the determination of the total concentration of trace elements (Se, Fe, Cu, Zn, Mg, Ca, Mn, Mo, I, Cd and Pb) and the various organic and inorganic selenium species present in human body fluids. Total elemental analysis involved the use of inductively coupled plasma mass spectrometry (ICP-MS). Speciation analysis utilised ion-pair high performance liquid chromatography (HPLC) coupled on-line to a hexapole collision cell ICP-MS. The methods that were developed were then applied to three separate studies. The effect of psychological stress on human fertility was determined by comparing the trace element levels in blood serum from 47 infertile women undergoing in-vitro fertilisation (IVF) treatment. Elemental data was compared with stress-hormone (plasma prolactin and serum cortisol) levels and Spielberger stress questionnaires. Statistical analysis showed no relationship between stress-hormones and blood serum trace element levels and that stress-hormones do not have an adverse effect on human fertility. A further study examined the total trace element levels of blood serum, follicular fluid, endometrial fluid and scalp hair from a study population of 97 women aged between 24 - 44 years undergoing IVF treatment. Selenium levels in blood serum were significantly lower in IVF patients in contrast to 18 (age and gender matched) control cases (P = 0.001, 35 degrees of freedom). This was in agreement with a previous study with infertile women, aged < 35 years. Zinc and manganese were determined in endometrial fluid, both showing a high degree of correlation (P = 0.001, 17 degrees of freedom) in the IVF population (no control samples were available for analysis). The levels of each element measured in scalp hair showed no correlation with the levels determined in any other matrix. A major contribution of this research involved speciation analysis of selenium in blood serum, seminal plasma and urine. Commercial selenium supplements were consumed over 28 days and the effect that this had on selenium levels (total and species) within the human body fluids was investigated. Consumption caused an increase in the levels of selenium within all human body fluids and in general, the total level of selenium was found to be higher than the sum of the species present. An in-vitro bioavailability procedure was performed on the supplements and showed that two selenium yeast commercial products contained different selenium species. Some selenium species were identified and the implications of this are discussed.

Induktiv gekoppelte Plasma-Massenspektrometrie mit Laserablation (LA-ICP-MS) wird zunehmend für die Einzelzellanalyse eingesetzt, jedoch wird eine weitere verbreitete Verbreitung durch den geringen Durchsatz behindert. Daher wurde in dieser Arbeit der Durchsatz von Einzelzellen-LA-ICP-MS untersucht und verbessert. Zunächst werden die beiden möglichen Ablationsmodi, Bildgebung und Einzelpunktanalyse (SSA), hinsichtlich ihrer analytischen Gütezahlen (Signal-Rausch-Verhältnis, Präzision, Genauigkeit, Durchsatz) verglichen. Hierfür wurden adhärente 3T3-Fibroblastenzellen mit zwei Metallfarbstoffen angefärbt und mit beiden Methoden mehrere Dutzend Zellen vermessen. SSA zeigte überlegene Eigenschaften hinsichtlich Durchsatz und Nachweisgrenzen. Darüber hinaus wurde gezeigt, dass >400 Zellen analysiert werden müssen, um zufriedenstellende Statistiken für einen quantitativen Vergleich der Ergebnisse zu erhalten, was als zu mühsam befunden wurde. Daher wurde ein Einzelzellen-Arraying-Schritt integriert, um eine automatisierte LA-ICP-MS-Analyse zu ermöglichen. Hierfür wurden zwei Arrayingverfahren getestet: Zunächst wurde das mikrofluidische Arraying von Zellen getestet, jedoch verhinderte das Einklemmen von weichen PDMS-Chips eine erfolgreiche Anwendung, und eine Neugestaltung des Chips wäre erforderlich. Daraufhin wurde eine neuartige Technologie getestet, die auf dem Arraying von Tröpfchen in Verbindung mit der Bilderkennung von Zellen beruht, wobei ein Anordnungsdurchsatz von 550 Zellen pro Stunde und eine beispiellose Einzelzellengenauigkeit (> 99%) gefunden wurde. In einem Proof-of-Principle-Experiment wurde ein Zellarray von THP-1-Suspensionszellen mittels LA-ICP-TOF-MS analysiert und erstmals gleichzeitig endogene und exogene Isotope einzelner Zellen als Isotopen-Fingerabdrücke von Zellen mit Nachweisgrenzen von lediglich wenigen hundert attogramm. Schließlich wurden diese Ergebnisse mit der derzeit gebräuchlichsten Analysemethode Single-Cell (sc)-ICP-MS verglichen.<br>Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is increasingly used for single-cell analysis. However, a more widespread use of LA-ICP-MS in single cell analysis is hampered by its low throughput. Hence, in this work the throughput of single cell LA-ICP-MS was studied and improved. First, the two possible ablation modes, imaging and single spot analysis (SSA) of single cells using a large laser spot, are compared regarding their analytical figures of merit (signal to noise, precision, accuracy, throughput), as well as regarding ease of operation and data evaluation. For that, adherent 3T3 fibroblast cells were stained with two metal dyes and several dozen cells were measured using both modes. SSA showed superior characteristics regarding throughput and detection limits. Moreover, it was shown that >400 cells must be analyzed to reach satisfactory statistics for a quantitative comparison of results, which would have been too laborious. Thus, a single cell arraying step was integrated to enable automated LA-ICP-MS analysis. Two different arraying methods were evaluated: First, arraying via hydrodynamic front trapping of cells using a microfluidic device was tested, but clamping of soft PDMS-chips prevented successful arraying and it was concluded that a major redesign of the chip is necessary. Secondly, and a novel technology relying on a microdroplet arrayer in conjunction with image recognition of cells was tested and a moderate arraying throughput (550 cells per hour) and an unprecedented single-cell accuracy (>99%) was found. In a proof of principle experiment, a cell array of THP-1 suspension cells was analyzed using LA-ICP-TOF-MS and endogenic and exogenic isotopes of individual cells were detected for the first time simultaneously as isotopic fingerprints of cells with detection limits as low as hundred attogram. Finally, these results were compared to the currently more commonly used analysis method single-cell (sc)-ICP-MS.

En la presente Tesis Doctoral la técnica de ablación laser acoplada a ICP-OES/MS ha sido empleada para analizar muestras sólidas, como catalizadores usados en el refinado del petróleo y polímeros. Se han llevado a cabo dos tipos de análisis, un análisis global de las muestras que proporciona información general y un análisis localizado que permite obtener información acerca de la distribución espacial de los elementos de interés en las muestras. Las diferentes variables de la técnica ablación láser son estudiadas con el fin de seleccionar aquellas que conducen una señal alta y estable, así como a un menor grado de fraccionamiento. Este estudio se realiza para cada tipo de muestra, ya que los resultados dependen de la matriz estudiada. Además, en esta Tesis doctoral se desarrolla un método de calibración para llevar a cabo un análisis cuantitativo de las muestras sólidas, basado en la deposición de patrones líquidos sobre la muestra sólida. Este método es conocido como “dried droplet calibration approach” (DDCA), y permite cuantificar elementos presentes en muestras sólidas sin necesidad de usar materiales de referencia sólidos. Este nuevo método de calibración compensa el fraccionamiento elemental y los efectos de matriz, proporcionando resultados exactos y preciosos para muestras complejas tales como vidrios, catalizadores y polímeros.

This Master’s thesis deals with the determination of selected micro and macro elements in bottled water purchased in retail chains Czech Republic. There are described macro elements and micro elements that occur in the waters, bottled waters legislation and the most frequent used instrumental methods for elemental analysis. In this work for the analysis of bottled water were used methods optical emission spectrometry with inductively coupled plasma (ICP-OES) and ion chromatography (IC). Elemental composition of bottled water after analysis corresponded to the composition indicated on the labels, there were recorded only minor deviations from the reported concentrations. All bottled water meets the conditions of the legislation of the Czech Republic. The measured data were statistically processed in the XL Stat program and by multivariate data analysis was examined whether it is possible to individual bottled water from each other based on the analyzes differentiate, which can help in verifying the authenticity of bottled water and in the detection of adulteration of bottled water for profit.

The work described within this thesis explores the use of HPLC coupled with ICPMS and ESI-MS in order to develop novel methods which overcome specific analytical challenges in the pharmaceutical industry. A membrane desolvation interface has been evaluated for coupling high performance liquid chromatography (HPLC) with inductively coupled plasma mass spectrometry (ICP-MS). Desolvation of the sample prior to reaching the plasma was shown to facilitate a versatile coupling of the two instrumental techniques, enabling chromatographic eluents containing up to 100 % organic to be used. This interface also allowed gradient elution to be used with ICP-MS. Tris(2,4,6-trimethoxyphenyl)phosphonium propylamine bromide (TMPP) was used for the derivatisation of maleic, fumaric, sorbic and salicylic acids to facilitate determination by HPLC-electrospray ionisation tandem mass spectrometry (ESIMS/ MS) in positive ion mode. Improvements in detection limits post-derivatisation were achieved, and this method was successfully used for the determination of sorbic acid in a sample of Panadol™. HPLC coupled with sector field inductively coupled plasma mass spectrometry (SF-ICP-MS) has been used for the determination of maleic, sorbic and fumaric acids after derivatisation with TMPP. This allowed 31P+ selective detection to be performed for these compounds, which are normally undetectable by ICP-MS. Optimal reagent conditions for the derivatisation of 0.1 mM maleic acid were: 1 mM TMPP; 10 mM 2-chloro-1-methylpyridinium iodide (CMPI); 11 mM triethylamine. The efficiency of the derivatisation reaction was estimated to be between 10-20%. Detection limits, estimated as 3 times baseline noise, were 0.046 nmol for TMPP and 0.25 nmol for derivatised maleic acid, for a 5 f.JL injection. Following on from this, a novel derivatising reagent, tris(3,5-dibromo-2,4,6- trimethoxyphenyl) phosphonium propylamine bromide (BrTMPP), was synthesised and subsequently characterised by proton NMR spectroscopy and ESI-MS. This was utilised to derivatise maleic acid, with a 9-fold increase in sensitivity gained when analysed by bromine selective detection as apposed to phosphorus selective ICP-MS. This derivatising reagent (BrTMPP) was also utilised to determine the degree of phosphorylation on phosphorylated peptides. A phosphorus containing carboxylic acid was successfully derivatised and the correct Br:P ratio was determined for this compound by ICP-MS. However, phosphorylated peptides were not successfully derivatised by BrTMPP. A combination of UV and phosphorus selective ICP-MS was also used to distinguish between phosphorylated and un-phosphorylated peptides after HPLC separation.

Made available in DSpace on 2014-10-09T12:33:42Z (GMT). No. of bitstreams: 0<br>Made available in DSpace on 2014-10-09T14:04:01Z (GMT). No. of bitstreams: 0<br>Dissertação (Mestrado)<br>IPEN/D<br>Instituto de Pesquisas Energéticas e Nucleares - IPEN-CNEN/SP

El número de aplicaciones de la energía laser en el campo científico crece día a día. Estas no solo se han extendido en los campos de química, física y ciencia de materiales, sino también en biología y medicina. Este artículo es una breve introducción a los principios fundamentales del funcionamiento del láser, así como a su aplicación en el campo de la química.<br>The number of applications of lasers in science is constantly growing, with applications stretching from chemistry, physics and materials science to biology and medicine. This article provides a short overview of the fundamentals of lasers and an introduction to the application of lasers and laser ablation in chemistry.

The theoretical part of the thesis deals with the chemical composition of cow’s milk, with the description of chosen methods of sample pretreatment and with the description of the used technique ICP-OES. The practical part is aimed at individual preparations of samples and at analysis of chosen chemical elements (Ca, Na, K and Mg). Milk is a really complicated polydisperse system, that’s the reason why the preparation of samples with milk is very important step before the measurement itself. In addition to accuracy choosing the sample adjustment method, other factors such as time, work intensity, or cost need to be considered when. In the thesis a comparison of four selected methods of sample preparation was made: direct analyse of milk, dilution with addition of Triton X-100, wet microwave ashing and destruction of matrix with TMAH (tetramethylammonium hydroxide). Selected elements were analysed with the help of ICP-OES. This diploma thesis builds on the bachelor thesis, which deals with the same problem. Final concentrations were compared with certified values of skimmed powdered milk. Data showed that the most accurate are methods of preparation of wet microwave ashing and destruction of matrix with TMAH. By using these methods, the effect of the dairy matrix that caused problems in the analysis, was largely eliminated. The diluted samples with and without Triton X-100 showed a bigger anomaly of measuring than the mineralization of wet ashing which came to the loss of analyte because of fat elements contained in milk.

A abordagem analítica do uso de Trace Elements (TEs) pode ser usada não só para entender o ambiente vivo e a dieta, mas até a diagênese pós mortem de qualquer resíduo humano usando a variabilidade nas composições elementares de dentes e ossos. Oito indivíduos foram amostrados do convento de San Pablo em Burgos usando seus dois tipos de tecido ósseo (ossos cortical e trabecular) do fêmur e esmalte dentário para cada caso. Três dessas amostras pertenciam à nave da igreja (século 16th -19th) enquanto o resto era encontrado no pátio do claustro pertencente ao século XIV-XVI. Essas amostras foram processadas na Espectrometria de Massa Plasmática Acoplada Induzamente (ICP-MS) para analisar as concentrações de Ca e P, bem como os TEs não essenciais e bio-essenciais, a fim de poder estabelecer a integridade das amostras e para descobrir quais TEs podem ser úteis para fazer inferências sobre a dieta antiga e a absorção diagenética e em que medida. Os dados de TE foram tratados usando diferentes ferramentas estatísticas e testes para encontrar possíveis diferenças de gênero ou mesmo diferenças intra-locais na dieta e também foram corroborados com informações coletadas a partir da análise de microwear. Verificou-se que a dieta dos indivíduos era de tipo misto com componentes vegetais e de carne, enquanto a presença de alimentos marinhos não pôde ser confirmada. Isto foi de acordo com os resultados de microwear para algumas das amostras. Usando as razões de Ba e Sr por Ca, verificou-se que os ossos corticais deram os resultados mais confiáveis para inferências sobre dieta, excluindo o uso de níveis de Mn e Fe que foram altamente afetados pela absorção diagenetica nos tecidos ósseos. Além disso, as amostras enterradas na nave da igreja podem estar consumindo mais proteínas de carne do que as enterradas no claustro, o que pode indicar uma diferença em seu status social ou uma mudança na dieta ao longo do tempo. Como esperado, para a maioria dos elementos, como Pb, Mn, Fe, Cu, os tecidos trabeculares foram os mais afetados pela absorção diagenetica, ademais, na em sua maioria superfície interna do eixo do fêmur; Abstract: The analytical approach of using Trace Elements (TEs) can be used not only to understand the living environement and diet but even post-mortem diagenesis of any human remains using the variability in the elemental compositions of both teeth and bones. Eight individuals were sampled from the convent of San Pablo in Burgos using their two types of bone tissues (cortical and trabecular bones) from the femur and tooth enamel for each case. Three of these samples belonged to the church nave (16th -19th C) while the rest were found from the cloister courtyard belonging to 14th -16th Century. These samples were processed in solution mode Inductively Coupled Plasma Mass Spectrometry (ICP-MS) to analyse concentrations of Ca and P as well as both non-essential and bio-essential TEs in order to be able to establish the integrity of the samples and to find out which TEs can be helpful in making inferences on ancient diet and diagenetic uptake and to which extent. The TE data was treated using different statistical tools and tests to find possible gender differences or even intra-site differences in the diet and was also corroborated with information gathered from microwear analysis. It was found that the diet of the individuals was of a mixed type with both vegetal and meat components while presence of marine food could not be confirmed. This was in accordance with the microwear results for some of the samples. Using the Ba and Sr ratios to Ca, it was found that cortical bones gave the most reliable results for inferences on diet excluding the use of Mn and Fe levels which were both highly affected by diagenetic uptake in the bone tissues. Additionally, the samples buried in church nave might be consuming more meat proteins than those buried in the cloister which might indicate a difference in their social status or a change in the diet through time. As expected, for most of the elements such as Pb, Mn, Fe, Cu, trabecular tissues were the most affected by diagenetic uptake moreover mosly at the inner surface of the femur shaft.