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Avaliação de metais em esgoto e lodo gerado em estações de tratamento, nos municípios de Jaguariúna e Campinas, empregando a fluorescência de raios x por reflexão total com radiação síncrotron (SR-TXRF) / Analysis of heavy metals in sewage and sludge from treatment plants in the cities of Campinas and Jaguariúna, using fluorescence x-ray total reflection with synchrotron radiation (SR-TXRF)Souza, Luciana Carla Ferreira de 22 August 2018 (has links)
Orientador: Silvana Moreira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-22T06:30:46Z (GMT). No. of bitstreams: 1
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Previous issue date: 2013 / Resumo: O rápido crescimento urbano e industrial nas ultimas décadas provocou alterações no meio ambiente, dentre eles a poluição dos corpos d'água, principalmente por metais que podem causar danos a saúde humana. Os municípios de Campinas e Jaguariúna estão inseridos na Região Metropolitana de Campinas (RMC), uma das regiões mais dinâmicas no cenário econômico brasileiro. Portanto, visando estudar a influencia antropogenica das cidades, foi avaliada a qualidade do efluente bruto e tratado e, do lodo gerado na estação de tratamento de esgoto de Anhumas, no município de Campinas e na estação de tratamento Camanducaia no município de Jaguariúna, ambas no estado de São Paulo, principalmente no que se refere à contaminação por metais. As analises foram realizadas pela técnica de Fluorescência de Raios X por Reflexão Total com Radiação Sincrotron (SR-TXRF) e os resultados comparados com as legislações vigentes. Para o efluente tratado os dados foram comparados as legislações CONAMA 357 e 430 que estabelecem limites para o descarte de efluentes nos corpos d'água e todos os elementos Cr, Mn, Fe, Ni, Cu, Zn, Ba e Pb apresentaram concentrações em conformidade com a legislação. Para o reuso na agricultura, cujos limites são definidos pela Instrução Técnica CETESB alguns dos elementos apresentaram concentrações acima do permitido e desta forma o efluente tratado não pode ser empregado para reuso. No caso do lodo os teores de Cr, Ni, Cu, Zn, Ba e Pb foram comparados aos valores máximos permitidos das legislações CONAMA 357 e 430 e os teores de todos os elementos ficaram abaixo do valor Maximo permitido, e desta forma existe a possibilidade de aplicação do lodo no solo agrícola, para as duas estações de tratamento de esgoto estudadas, Anhumas (Campinas) e Camanducaia (Jaguariúna) / Abstract: The rapid urban and industrial growth in recent decades caused changes in the environment, including pollution of water bodies, mainly of metals that can cause harm to human health. The cities of Campinas and Jaguariuna are inserted in the Metropolitan Region of Campinas (MRC), one of the most dynamic regions in the Brazilian economy. Therefore, to study the influence of anthropogenic citiesit was evaluated the quality of raw and treated wastewater and sludge generated in the wastewater treatment plant of Anhumas, in Campinas and the treatment plant in the municipality of Camanducaia Jaguariuna, both in state of Sao Paulo, particularly with regard to metal contamination. Analyses were performed by the technique of X-ray Fluorescence by Total Reflection with Synchrotron Radiation (SR-TXRF) and the results compared with existing laws. For the treated effluent data were compared laws CONAMA 357 and 430 that set limits for the discharge of effluents into water bodies and all the elements Cr, Mn, Fe, Ni, Cu, Zn, Pb and Ba concentrations presented in accordance with legislation. To reuse in agriculture, whose limits are defined by the Technical Instruction CETESB some elements had concentrations above the permitted and thus the treated effluent can't be used for reuse. In the case of sludge contents of Cr, Ni, Cu, Zn, Ba and Pb were compared with maximum permissible values of the laws CONAMA 357 and 430 and the contents of all elements were below the maximum allowable value, and thus it is possible application of sludge to agricultural soil, for the two sewage treatment stations studied, Anhumas (Campinas) and Camanducaia (Jaguariuna) / Doutorado / Saneamento e Ambiente / Doutora em Engenharia Civil
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Structural Studies of Boron Nitride Compounds Under Extreme ConditionsSterling, Spencer 27 October 2021 (has links)
This document will present the work done on BN under high pressure conditions, both at room temperatures and at high temperatures under laser heating conditions. These experiments are performed to identify possible phase transitions within the BN system and characterize the materials present under the given conditions using a mixture of X-ray diffraction and Raman and infrared spectroscopies are employed. A review of the background and motivations for studies of BN under extreme conditions, as well as the techniques employed, is given as an introduction.
A phase transition from hexagonal boron nitride (hBN) to wurtzite boron nitride (wBN)
is observed beginning at 9 GPa and room temperature, with coexistence of the two phases until 14 GPa for hydrostatic conditions and to above 20 GPa for non-hydrostatic conditions. This transition is partially reversible below 2 GPa. The formed wBN has a high concentration of defects. For recovered samples, defects couple with the 532.18 nm excitation laser producing a heating effect, observed as a Raman downshift with increasing laser power.
The bulk modulus B0 and pressure derivative of the bulk modulus B0′ of hBN are estimated to be 30.6 ± 0.5 GPa and 8.7 ± 0.7, respectively. The bulk modulus of wBN is estimated to be 392 ± 5 GPa, leading to a Vickers hardness of 68 ± 1 GPa. Extra diffraction lines are observed for hBN samples loaded with N2, indicating a potential new structure arising from a reaction of N2 with hBN, but Raman spectroscopy fails to corroborate this finding. The crystallinity of the hBN samples and the choice of pressure transmitting medium are shown to have little to no effect on the estimated physical properties of hBN.
Laser heating is performed on hBN with various sample assemblies. The effectiveness of different assemblies is discussed. NaCl is used as a pressure and temperature gauge local to the X-ray probe to contrast the stationary ruby pressure gauge and the non-local black body temperature measurement. A large contrast between the two temperature measurements yields doubt that the intended temperatures of around 2000 K are produced in the sample. Observation of the proposed high-pressure high-temperature transition to body-centered tetragonal BN or intercalated BN cannot be confirmed, likely due to insufficient heating.
The prospects for studying Li-BN intercalation compounds under extreme conditions
is discussed. An initial experiment on the system studied with X-ray diffraction is unable to confirm heating of the material nor the presence of intercalation compounds.
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Interpretation and relativistic simulation of selected electronic transitions:decays of M-shell hole states in atomic Cr, Br and RbKeskinen, J. (Juho) 28 November 2019 (has links)
Abstract
In this thesis electronic structure of atomic chromium, rubidium and bromine are studied experimentally and theoretically through transitions and decay processes originating from selected M-shell hole states. The experiments are conducted with traditional methods of electron spectroscopy as well as more recent multicoincidence methods using pulsed synchrotron radiation and a magnetic bottle spectrometer. The observed electronic transitions are theoretically simulated with multiconfiguration Dirac-Fock method. Finally, the calculations are used to interpret the measured spectra to investigate the energy level structure and electron dynamics of the studied elements. / Original papers
Original papers are not included in the electronically distributed version of the thesis.
Keskinen, J., Huttula, S.-M., Mäkinen, A., Patanen, M., & Huttula, M. (2015). Experimental and theoretical study of 3p photoionization and subsequent Auger decay in atomic chromium. Radiation Physics and Chemistry, 117, 209–216. https://doi.org/10.1016/j.radphyschem.2015.08.018
Keskinen, J., Lablanquie, P., Penent, F., Palaudoux, J., Andric, L., Cubaynes, D., … Jänkälä, K. (2017). Initial-state-selected MNN Auger spectroscopy of atomic rubidium. Physical Review A, 95(4). https://doi.org/10.1103/physreva.95.043402
http://jultika.oulu.fi/Record/nbnfi-fe201706207380
Keskinen, J., Jänkälä, K., Huttula, S.-M., Kaneyasu, T., Hikosaka, Y., Shigemasa, E., … Lablanquie, P. (2019). Auger decay of the 3d hole in the isoelectronic series of Br*, Kr⁺ and Rb²⁺. Manuscript in preparation.
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Studium pokročilých hořčíkových slitin s vysokou pevností pomocí in-situ metod / Study of advanced high strength magnesium alloys by in situ techniquesFekete, Klaudia January 2019 (has links)
The aim of the present doctoral thesis was to reveal the active deformation mechanisms in novel high strength magnesium (Mg) alloys using advanced in-situ techniques with high time and space resolutions. The deformation behavior of two extruded Mg-LPSO alloys with a different volume fraction of the long-period stacking ordered (LPSO) phase was investigated in tension and compression at room temperature and in compression at 200 řC, 300 řC, and 350 řC. In order to support the results obtained by in-situ acoustic emission and synchrotron diffraction methods, detailed microstructure investigation was provided by transmission and scanning electron microscopy, particularly the backscattered electron imaging and electron backscatter diffraction technique were used. The results indicate that both temperature and the LPSO phase content significantly influence the plasticity of the magnesium matrix, particularly they affect the activation of extension twins and non-basal slip. Moreover, both parameters have a high impact on the formation of the deformation kinks in the LPSO phase. Keywords: Mg-LPSO alloys, deformation mechanisms, acoustic emission, synchrotron diffraction, in-situ methods.
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In Situ Ptychography of Heterogeneous Catalysts using Hard X-Rays: High Resolution Imaging at Ambient Pressure and Elevated TemperatureBaier, Sina, Damsgaard, Christian D., Scholz, Maria, Benzi, Federico, Rochet, Amélie, Hoppe, Robert, Scherer, Torsten, Shi, Junjie, Wittstock, Arne, Weinhausen, Britta, Wagner, Jakob B., Schroer, Christian G., Grunwaldt, Jan-Dierk 03 June 2020 (has links)
A new closed cell is presented for in situ X-ray ptychography which allows studies under gas flow and at elevated temperature. In order to gain complementary information by transmission and scanning electron microscopy, the cell makes use of a Protochips E-chipTM which contains a small, thin electron transparent window and allows heating. Two gold-based systems, 50 nm gold particles and nanoporous gold as a relevant catalyst sample, were used for studying the feasibility of the cell. Measurements showing a resolution around 40 nm have been achieved under a flow of synthetic air and during heating up to temperatures of 933 K. An elevated temperature exhibited little influence on image quality and resolution. With this study, the potential of in situ hard X-ray ptychography for investigating annealing processes of real catalyst samples is demonstrated. Furthermore, the possibility to use the same sample holder for ex situ electron microscopy before and after the in situ study underlines the unique possibilities available with this combination of electron microscopy and X-ray microscopy on the same sample.
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A study of the gamma-ray emission from the blazar S50716+71 using the Fermi-LAT telescopeVislander, Fredrik January 2022 (has links)
This thesis sums up a bachelor project in which gamma-ray emission from an extra-galactic source (S50716+71) is studied using data collected by the Fermi Large Area Telescope (LAT). The emission consists of 12,5 years of data (April 2008 to February 2020) in the energy range 100 MeV - 300 GeV. The source has a high significance (>298) and is believed to be an active galactic nucleus in which there have to be mechanisms able to accelerate photons to these high energies. The mechanisms are believed to be of non-thermal origin and the general consensus is that they are the synchrotron radiation-process as well as the inverse Compton-process. These processes are discussed to some extent in the thesis as part of a fairly large theoretical background. The data was analyzed in several ways. The Enrico software contained in the package Fermitools provided by NASA was used to create curves of the flux as a function of time (lightcurves) as well as spectral distributions. The light curve showed that the source varies considerably with hardly any “quiet periods” at all during the twelve-year period. The light curve also showed a fast rise and fall of intensity between the high intensity and low intensity points. Spectral analyses were made for six chosen time-periods of interest through the fitting of three different functions, a powerlaw-function, a logparabola-function and a powerlaw function with exponential cutoff. The powerlaw function with exponential cutoff was favored in all periods except one where the log parabola-function was preferred. The data from one of the periods was then put into a multi-wavelength context of the source showing that the data is in agreement with previous collected data. This broad spectrum was then used to model the underlying energy distribution through a theoretical framework called the Synchrotron Self-Compton model (SSC). This was done using a modelling software called JetSet. The modelling resulted in a reasonable fit of the data and parameters that overall (at least in magnitude) seem to agree with results from other publications.
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Nouvelle approche d'imagerie pour l’étude de la biodistribution de nanomédicaments / New imaging approach to the biodistribution study of innovative nanomedicineEpaule, Céline 04 December 2017 (has links)
La distribution in vivo des médicaments est étudiée par des techniques quantitatives faiblement ou non résolues spatialement. Avec l'apparition des thérapies personnalisées, des études plus approfondies sont nécessaires pour connaître précisément le comportement des molécules vectorisées sous la forme de nanoparticules (NPs). Dans le cadre du programme européen Ternanomed, ce projet de recherche a pour objectif d’évaluer la capacité de deux techniques d’imagerie appliquées à l’étude de la distribution de nanomédicaments à base de squalène et de Cis platine (Cis-Pt). Ces deux techniques ont été sélectionnées pour leur apport d’informations complémentaires à l’échelle des organes et des tissus : i) l’imagerie par résonnance magnétique (IRM) pour suivre in vivo la biodistribution de NPs modèles à base de Cis-Pt et BiSqualène (BiSQ), marquées par des agents de contraste type oxyde de fer (USPIO), ii) l’imagerie de microfluorescence X, couplée au rayonnement synchrotron (SR-μXRF), qui ne nécessite pas de marquage préalable des nanomédicaments, pour le suivi tissulaire du Cis-Pt.Concernant l’approche par IRM, nous avons encapsulé avec succès nos USPIO synthétisées au sein des NPs de Cis-Pt BiSQ (210nm, polydispersité 0,1), tout en leur conférant un pouvoir contrastant à 7 tesla (r2=404 ms.mol-1 et r1=3 ms.mol-1). Ces NPs nouvellement préparées sont également traçables chez notre modèle murin Nudes. Les résultats de biodistribution montrent une arrivée rapide du contraste dans les organes épurateurs : le foie et la rate (5 minutes après l’injection). Au final, l’analyse par IRM a permis d’obtenir les données de biodistribution en temps réel des NPs à base de Cis Pt BiSQ, grâce au suivi du contraste apporté par les USPIO encapsulés. Concernant l’imagerie par SR-μXRF, nous avons démontré que cette technique est suffisamment sensible pour détecter et cartographier le Cis-Pt, vectorisé par nos NPs modèles. La distribution du Cis Pt a été quantifiée localement à partir d’une référence interne de concentration connue, le Zinc, à partir de notre méthode validée par le dosage globale du Platine par spectrométrie d’absorption atomique. Lorsque notre référence tissulaire n’est pas distribuée de façon homogène, une méthode semi-quantitative a été mise au point pour comparer la distribution à 2h, 8h et 24h, tel qu’au niveau des coupes de tumeurs PANC-1.Au final, ces travaux ont permis de démontrer, que la SR-μXRF et l’IRM sont des approches de choix pour l’étude pharmacocinétique et pharmacodynamique de nanomédicaments tels que les NPs à base de Cis-Pt. La technique de microfluorescence X contribue au caractère original et pionnier de ce travail de recherche, apportant des nouveaux résultats de détection et quantification important dans le domaine des nanomédecines. / Nowadays, the in vivo distribution of drugs is studied by non-spatial or partially spatial quantitative techniques. With the development of personalized therapies, many studies are required to know the in vivo behaviour of these innovative treatments, which target drugs, such as nanoparticles (NPs). Into the European funded program Ternanomed, the aim of this multidisciplinary research project was to evaluate two complementary imaging methods to study the distribution of squalene and Cis platinum (Cis Pt) NPs. The 2 imaging methods were selected to provide complementary data at the scale of organs and tissues: i) Magnetic resonance imaging (MRI) to monitor the in vivo biodistribution of NPs models based on Cis-Pt and BiSqualene (BiSQ), labelled with "UltraSmall Iron Oxide Particle" (USPIO) contrast agents, ii) X-ray microfluorescence imaging, coupled with synchrotron radiation (SR-μXRF) without any labelling of these nanomedicines, by following the Cis-Pt drug distribution into tissues.Regarding the MRI approach, we first successfully prepared Cis-Pt BiSQ NPs loading with USPIO (210nm, polydispersity 0,1). These NPs were given a contrast at 7 Tesla (r2 = 404 ms.mol-1 and r1 = 3 ms.mol-1). These newly prepared and characterized NPs were also trackable into our Nude murine model. The results show a rapid arrival of contrast in the liver and spleen scavengers (5 minutes after injection). Ultimately, MRI analysis yielded real-time biodistribution data for Cis-Pt BiSQ-based NPs by monitoring the contrast provided by encapsulated USPIO. Regarding the SR-μXRF imaging analysis, we demonstrated that this technique is very sensitive to detect and map the Cis-Pt distribution, the drug vectorized by our squalene NPs models. Additionally, a local quantitative analysis is feasible when a microelement present in the tissue is used as a reference, in our study the Zinc element. The distribution of Cis-Pt was quantified in the hepatic, renal and fat tissues, after 2h and 24h, with our method validated by the global Platinum microanalyse using atomic absorption spectrometry. When the tissue reference appears not homogenously distributed, a semi-quantitative analysis method is possible to compare the distribution such as into PANC-1 tumour sections.Finally, these two complementary approaches illustrate the use of SR-μXRF and lay the optimized bases of MRI to study the pharmacokinetics and pharmacodynamics of two new types of Cis-Pt/squalene NPs. The SR-μXRF technique, newly used in pharmaceutical field, had an effective contribution to these original and pioneering research studies with an original way of in vivo assessment of the distribution of drug embedded into nanomedicine system. The issue of detecting correct and measurable distribution of the drugs is extremely important, timely and relevant to improve current knowledge in the state of the art. This research study brings new data which can produce significant impact to the overall area of nanomedicine.
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Synchrotron X-ray Scanning Tunneling Microscopy Investigation of Interfacial Properties of Nanoscale MaterialsChang, Hao January 2018 (has links)
No description available.
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Characterization of Morphological and Chemical Properties of Scandium Containing Cathode MaterialsMroz, Michael V. 02 June 2020 (has links)
No description available.
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X-ray Measurements of Mass and Temperature Distributions in Multiphase FlowsNaveed Rahman (12898085) 24 June 2022 (has links)
<p>Multiphase flows, such as liquid/gas and solid/gas, dominate many different areas of life, including the medical, agricultural, propulsion, and chemical industries. Gaining insight into the dynamic processes that drive these multiphase flows can therefore have far-reaching impact in many sectors of scientific research. Of key interest is the non-invasive tracking of important state properties such as the mass and temperature distributions in high optical depth multiphase flows. To accomplish this, X-ray diagnostic approaches are utilized due to their ability to probe complex phenomena without being hampered by multiple scattering that arise from complex interactions at the flow surface boundaries.</p>
<p>This work accomplishes the measurement of mass distribution through time-resolved tomographic reconstructions of the liquid mass distributions in fuel sprays within liquid/gas flows. The developed diagnostic tool shown here uses a novel multiple line of sight tube source tomography setup to obtain simultaneous time-resolved two-dimensional radiographs of different spray geometries at various perspectives. Through tomographic reconstruction, these radiographs are converted into volumetric reconstructions to give a true sense of mass distribution—where exactly is the liquid mass located in the <em>x</em>, <em>y</em>, <em>z</em> spatial extents at a specific moment in time <em>t</em>? This technique is first showcased in a simple spray as a feasibility test and later applied to a more complex spray geometry and compared against other state-of- the-art diagnostics for a full quantitative understanding of the developed technique. Outside of tomography, improvements in decreasing the uncertainties in line of sight averaged mass distribution measurements in radiography imaging experiments are also showcased through source characterization efforts both for tube source and synchrotron source experiments.</p>
<p>Efforts in ascertaining the temperature distributions in liquid/gas flows is done through an application of wide angle X-ray scattering, a technique that is commonly used in the materials, chemistry, and biology sciences but has yet to be widely used in the propul- sion community. These newly developed X-ray scattering measurements are accomplished through the use of a focused monochromatic beam available at the Advanced Photon Source synchrotron facility, and is applied first in calibration jets and later towards more complex dynamic sprays and multi-species liquid solutions.</p>
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