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The use of solid state imagers as X-ray detectorsMagorrian, Brian Geoffrey January 1989 (has links)
No description available.
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Étude in situ des évolutions microstructurales d'un acier inoxydable martensitique à l'azote au cours d'une succession de traitements thermiques / In situ study of the microstructural evolutions of a nitrogen martensitic stainless steel during a succession of thermal treatmentsBénéteau, Adeline 14 March 2007 (has links)
L’acier inoxydable martensitique à l’azote XD15NW (Fe–15,5%Cr–0,4%C–0,2%N–1,7%Mo–0,3%V) est un candidat attractif pour les bagues de roulement des moteurs spatiaux. Il possède de bonnes propriétés mécaniques et une bonne résistance à la corrosion grâce à l’azote qui contribue à la formation de précipités de petite taille dans une matrice à grains fins. Nous avons étudié les évolutions microstructurales de cet acier au cours d’une succession de traitements thermiques: austénitisation et trempe, revenu, traitement de surface par induction. Outre les techniques usuelles d’analyse microstructurale (MEB, MET, dilatométrie), nous avons utilisé la diffraction des rayons X de haute énergie in situ (rayonnement synchrotron). Cette technique nous a permis d’obtenir les cinétiques d’évolution des phases en fonction de la température et du temps, les gradients de microstructure au sein de pièces traitées par induction en surface et les évolutions de paramètres de maille des phases / The nitrogen martensitic stainless steel XD15NW (Fe–15,5%Cr–0,4%C–0,2%N–1,7%Mo–0,3%V) is an attractive candidate for the bearing rings of the space engines turbopumps. It owns good mechanical properties and a good corrosion resistance thanks to the nitrogen which contributes to the formation of little size precipitates in a fine grains matrix. The microstructural evolutions of this steel during a succession of thermal treatments were studied: austenitisation and quenching, tempering, induction surface heat treatment. In addition to the usual techniques of microstructural analysis (SEM, TEM, dilatometry), the in situ high energy synchrotron X-ray diffraction was used. It allowed to obtain the evolution kinetics of the phases as a function of temperature and time, the microstructural gradients in induction treated samples and the lattice parameters evolutions which are linked to the chemical composition or the internal stresses evolutions of the phases
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Morphology and material stability in polymer solar cellsHansson, Rickard January 2015 (has links)
Polymer solar cells are promising in that they are inexpensive to produce, and due to their mechanical flexibility have the potential for use in applications not possible for more traditional types of solar cells. The performance of polymer solar cells depends strongly on the distribution of electron donor and acceptor material in the active layer. Understanding the connection between morphology and performance as well as how to control the morphology, is therefore of great importance. Furthermore, improving the lifetime of polymer solar cells has become at least as important as improving the efficiency. In this thesis, the relation between morphology and solar cell performance is studied, and the material stability for blend films of the thiophene-quinoxaline copolymer TQ1 and the fullerene derivatives PCBM and PC70BM. Atomic force microscopy (AFM) and scanning transmission X-ray microscopy (STXM) are used to investigate the lateral morphology, secondary ion mass spectrometry (SIMS) to measure the vertical morphology and near-edge X-ray absorption fine structure (NEXAFS) spectroscopy to determine the surface composition. Lateral phase-separated domains are observed whose size is correlated to the solar cell performance, while the observed TQ1 surface enrichment does not affect the performance. Changes to the unoccupied molecular orbitals as a result of illumination in ambient air are observed by NEXAFS spectroscopy for PCBM, but not for TQ1. The NEXAFS spectrum of PCBM in a blend with TQ1 changes more than that of pristine PCBM. Solar cells in which the active layer has been illuminated in air prior to the deposition of the top electrode exhibit greatly reduced electrical performance. The valence band and absorption spectrum of TQ1 is affected by illumination in air, but the effects are not large enough to account for losses in solar cell performance, which are mainly attributed to PCBM degradation at the active layer surface. / The performance of polymer solar cells depends strongly on the distribution of electron donor and acceptor material in the active layer. Understanding the connection between morphology and performance as well as how to control the morphology, is therefore of great importance. Furthermore, improving the lifetime has become at least as important as improving the efficiency for polymer solar cells to become a viable technology. In this work, the relation between morphology and solar cell performance is studied as well as the material stability for polymer:fullerene blend films. A combination of microscopic and spectroscopic methods is used to investigate the lateral and vertical morphology as well as the surface composition. Lateral phase-separated domains are observed whose size is correlated to the solar cell performance, while the observed surface enrichment of polymer does not affect the performance. Changes to the unoccupied molecular states as a result of illumination in ambient air are observed for the fullerene, but not for the polymer, and fullerenes in a blend change more than pristine fullerenes. Solar cells in which the active layer has been illuminated exhibit greatly reduced electrical performance, mainly attributed to fullerene degradation at the active layer surface. / <p>Paper 2 ingick som manuskript i avhandlingen. Nu publicerad. </p>
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Structure Pharmaceutics Based on Synchrotron Radiation X-Ray Micro- Computed Tomography: From Characterization to Evaluation and Innovation of Pharmaceutical StructuresYin, Xianzhen January 2016 (has links)
Drug delivery systems (DDS) are essentially pharmaceutical products for human
therapy, typically involving a mixture of active ingredients and excipients. Based
upon quantitative characterization of structure, the thesis introduces the concept
of classifying the architecture of DDS into four levels by their spatial scale and
the life time period. The primary level is recognised as the static structure of the
whole dosage form with a size from μm to cm with the final structure generated
by formulation design. The secondary level categorises the structures of particles
or sub-units to form a DDS with sizes from nm to mm as key units in processing
such as mixing, grinding, granulation and packing; The tertiary level represents
the dynamic structures of DDS during the drug release phase in vitro or in vivo
incorporating the structure size range from nm to mm, which undergo changes
during dissolution, swelling, erosion or diffusion. The spatial scale for the
quaternary level is defined as the meso or micro scale architecture of active and
non-active molecules within a DDS with sizes from Å to μm for the molecular
structure of drug and excipients.
Methods combining X-ray tomography, image processing, and 3D
reconstructions have been devised and evaluated to study systematically
pharmaceutical structures and correlate them with drug release kinetics of DDS.
Based on the quantitative structural information of pharmaceutical intermediates
and dosage forms, it is possible now to correlate structures with production
processing, behaviour and function, and the static and dynamic structures of DDS
with the release kinetics. Thus, a structure-guided methodology has been
established for the research of DDS. / Chinese Academy of Sciences
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Insights of Taste Masking from Molecular Interactions and Microstructures of MicrospheresGuo, Zhen January 2017 (has links)
The effects of taste masking are determined by interactions between drug and excipients as well as the microstructures of the particulate drug delivery systems (DDS). Cyclodextrin (CD) is a widely used taste masking agent, to which the relationship between kinetic parameters (Ka and Kd) of a drug and taste masking remains unexplored, which is investigated for the first time in this study. A data base of the kinetic parameters for drug-CD was established by Surface Plasmon Resonance Imaging (SPRi) and High Performance Affinity Chromatography (HPAC). Combined with the electronic tongue, Ka and Kd based models for the taste masking effect of HP-β-CD were successfully established and applied to the prediction of taste masking effects. Paracetamol was used as a model drug for taste masking formulation optimization. As well as drug release the microstructure of solid DDS has considerable influence on drug taste. The microstructure of lipid microspheres and the molecular distribution of drug and excipients in lipid microspheres were investigated by Synchrotron radiation-based micro-computed tomography (SR-μCT) and Synchrotron radiation-based Fourier-transform infrared spectromicroscopy (SR-FTIR), respectively. The results demonstrated that the polymeric formulation components as well as shape and particle size of the drug were the key factors to taste masking of paracetamol by inhibiting bust release thereby reducing the interaction intensity of the bitterness. The FTIR absorption spectra confirmed the deposition and formation of chitosan and gelatin films on the drug microsphere surface by layer-by-layer coating. In conclusion, this research demonstrates the molecular kinetic basis of CD taste-masking as well as microstructural basis of particle systems for bitter taste masking.
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An investigation, using synchrotron radiation and other techniques, of the composition of San rock art paints and excavated pigments from Maqonqu shelter, and comparative paint data from three other sites in KwaZulu-Natal, South Africa.Escott, Boyd John. January 2011 (has links)
This study aimed to: 1) characterise the individual San parietal art rock art paint colours; 2) relate
paint compositions to erosion susceptibility; 3) determine if paint pigments can be related to pigment
samples excavated from a Shelter deposit, and/or a variety of field samples; and 4) determine if paint
samples from geographically distinct sites can be distinguished on their composition. A combination
of mineralogical (X-ray diffraction (XRD), synchrotron micro-XRD (μ-XRD)) and chemical (energy
dispersive X-ray micro-analysis (EDX), X-ray fluorescence spectrometry (XRF), and synchrotron
micro-XRF (μ-XRF)) analytical techniques were used.
Maqonqo Shelter (MQ), 35 km south-east of Dundee, KwaZulu-Natal, South Africa, was the
primary study site chosen as it contained both a large number of paintings, as well as a large deposit.
Thirty paint (of various colours) and 3 blank wall samples were collected using Silver Mylar tape and
analysed using a combination of EDX, μ-XRD and μ-XRF techniques. Sixty two large (> 2.5 g)
‘ochre’ pieces were selected from the upper three layers of the deposit and analysed using XRD, XRF
and EDX. A further 63 small pieces (< 2.5 g) were analysed using μ-XRD and μ-XRF techniques.
To compare the MQ paint samples with potential source materials, three distinct sample sets were
collected. The first included samples of the Shelter wall and surface rocks located near the painted
panel (analysed by XRD, XRF and EDX). A second sample set of 17 samples was collected from the
surrounding landscape (± 3 km radius of MQ; analysed by XRD and XRF). Their selection was based
on ease of accessibility, degree of pulverulence, and perceived Fe content i.e., red and/or yellow
colouration. No white sources were found. A third set of 11 samples (obtained from six sites, analysed
using XRD and XRF) was collected within ± 50 km distance of the Shelter. Their selection was based
on old mining survey reports that detailed the location of Fe ore outcrops.
Paint samples from three additional shelters i.e., Fergies Cave (FC), Giants Castle Game Reserve,
central Drakensberg; Sheltered Vale (SV), Mount Currie District, south-western KwaZulu-Natal; and
Twagwa Shelter (TW), Izingolweni District, southern KwaZulu-Natal, were collected to compare
paint composition over distance. Site selection was determined according to the following criteria: 1)
the shelters had to reside a significant distance away from the primary site so as to minimise any
possible interaction that might have existed between the authors of the respective artworks (each site
is at least 100 km distant from the other); 2) each had to be located upon a distinct geological
formation so that external influences from different regions, and their possible affects on the paint
samples, could be noted; and 3) the climatic regimes of each of the shelters should be relatively
distinct. Fifteen paint and nine blank wall samples were collected from the three shelters (three each
of red, white and blank samples; analysed using EDX, μ-XRD and μ-XRF), with the exception that no
white samples were collected from FC.
In total, 673 EDX, 212 μ-XRD, 378 μ-XRF, 98 XRD, 98 XRF and 6 ICP-MS traces were
produced and analysed. Due to the extremely heterogeneous nature of the paint samples at the microii
scale, the more generalised EDX reduced window scans were used as the basis of the paint samples’
characterisation, with the data obtained from the more precise μ-XRD and μ-XRF techniques
providing additional supportive information. Irrespective of colour, almost all of the MQ paint
samples had elevated Ca contents that tended to increase in the order of black < orange £ red and
yellow < pink < white. The predominant Ca-based mineral was gypsum, although Ca-oxalates,
whewellite and weddellite, were also present. The blank samples collected from MQ also had high
gypsum content, but no Ca-oxalate. It is thus proposed that the Ca-oxalates formed after the painting
event and were derived from the original paint constituents.
The white pigments consisted of gypsum (dominant), anhydrite, bassanite and whewellite, or a
combination thereof. Whewellite increased within increasing paint depth, while gypsum showed the
reverse trend. This indicates that, whilst both gypsum and whewellite were originally present within
the original paint pigment, additional gypsum has been added via secondary evaporite deposition.
Although initially considered to be sourced along with the gypsum, another potential whewellite
source is organic additives. The most likely source for the white pigments would be precipitates found
on sandstone walls of shelters near MQ. Of more immediate importance, however, is that the
pigments, being gypsum based, are water-soluble and thus susceptible to erosion.
Most of the orange paints had an elevated Al content and contained gibbsite, suggesting bauxitic
material associated with locally sourced dolerite within the Ecca Series within KwaZulu-Natal (as
evidenced by their respective Ti levels). Two samples were so similar that it is likely that the same
pigment was utilised in the creation of both images. Two samples did not contain high Al contents,
however, indicating that they were probably sourced from the soft, ochreous material found within
local Fe nodules.
A consistent combination of goethite and haematite, together with a low Al and elevated Ti
content, indicate that the yellow and red samples were probably sourced from Fe nodules found
locally, the red samples differing from the yellow pigments primarily in their higher haematite
content. A low Si and relatively low Fe content discounts red sands/clays and Fe-ores as sources of
the red pigments. The red samples were ‘thinner’ than the other samples with quartz contents
comparable to those of the blank samples. The thin nature of the red paints, the erratic distribution of
whewellite upon the paint surfaces, the dominance of gypsum and, to a certain extent quartz, all
strongly suggest that the red paints are at least partly absorbed into the surface of the Shelter wall.
This, together with the strong staining ability of haematite, is probably the most important reason that
the red pigments have outlasted images painted in other colours. It may also account for the high
degree of variability found within the red paint dataset, though age differences between the sampled
images could also be a contributing factor.
The single dark red paint sample, except for an elevated Mn content, was very similar in many
ways to the red paint samples analysed. The only readily available pigment source identified that had
both low Al and high Fe and Mn contents, was plinthite. The pink samples represented the ‘middleiii
ground’ between the red and white paints, suggesting that this colour was the result of a blending of
the two. The black paint sample had the highest recorded Fe content of the entire paint dataset. A high
Mn and relatively low Al content suggest that a soft inner core of an Fe nodule was used in its
manufacture. The presence of maghemite and a dark colouration strongly suggest that the
manufacture also involved calcination.
The initial distinction between the paint and excavated samples was that the former all exhibited
elevated Ca and S values due to the deposition of secondary evaporite minerals. Even when taking
these additional deposits into account, however, the two datasets still remained distinct indicating that
the excavated materials sampled were not utilised in the manufacture of the MQ paints. A potential
exception concerned the orange paint samples, which were similar in composition to both doleritic
samples from deeper excavated layers and the local (weathered doleritic samples) and distant (bauxite
samples) field samples. Whilst weathered dolerite/bauxitic material was clearly the source of the
orange pigments, a more detailed investigation is needed to find a precise location. No other
relationships between the paint pigments and the excavated pigments and field samples were
established.
A comparison of the blank samples from all four study sites showed that the techniques used
could distinguish between different sites despite sampling the smallest and, relatively speaking,
poorest quality samples. The FC blank samples had elevated C and Ca contents (associated with Caoxalates).
The conditions within this Shelter favour the formation of weddellite and whewellite, the
former not typically found at the other three sites. In addition, low K, Si and Al contents (often
associated with sandstone matrix minerals) indicate that the surface of the relatively dense, compact
Cave sandstone is more resistant to physical erosion compared to the other sites, and/or FC shelter
experiences a high amount of secondary deposition, with the result that a majority of the samples are
composed of evaporite minerals. The SV samples were composed primarily of the evaporite-type
minerals, with only minor sandstone ‘contamination’ indicated by quartz and kaolinite. The quartz
content, whilst not always high, was present in most of the samples analysed, possibly indicating a
greater amount of more uniform surface erosion (relative to the other sites). The TW blank samples
were distinct from the other shelters’ as they contained no Ca-based minerals but did contain the very
rare mineral schlossmacherite.
A comparison of the paint colours also revealed differences between the different shelters. Whilst
the white samples from SV and MQ are dominated by whewellite and gypsum (minerals probably
present within the pigments when they were applied), the presence of quartz, sanidine and apatite in
the SV samples indicated a degree of shelter wall ‘contamination’, with anhydrite, bassanite and
glushinskite suggesting climatic variations that favoured various evaporite depositional regimes. The
TW white paint contained minimal secondary deposited minerals common in the other shelters. The
one mineral that is dominant within the TW samples is minamiite. As this mineral was not identified
in any of the blank samples, it is likely that this mineral originates from the original pigment source.
The TW white paints also contained 10 to 40 times more Zn than those recorded for any of the other
paint samples. This was possibly present within the structure of greigite.
The red SV samples could be distinguished from MQ red samples by the presence of wall
‘contaminants’ in a manner similar to that described for the white samples. The TW samples indicate a change in pigment source and/or manner of paint manufacturing technique, for these red samples
contained minamiite. This mineral is white and thus its selection could not have been based on colour
but rather it must represent a paint additive. With the exception of only one sample from TW, no
goethite was found within any of the red samples collected from the three additional sites indicating a
different haematite source to that of MQ.
An interesting facet of this study, although not directly addressed, concerns what the results do
not show with respect to the compositional nature of the pigments analysed. Most texts available
today list a number of pigment sources stated to have been utilised in the manufacture of the San
parietal rock art. This study has shown that very few of these potential sources were utilised within
the four shelters investigated. In addition, this study has also highlighted the presence of minerals
about which little is known, yet which appear to be commonly associated with parietal rock art. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2011.
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Caracterização de cálculos urinários humanos inteiros de rim e bexiga usando difração de raios X e microtomografia computadorizada / Characterization of human urinary calculi from bladder and kidney by X Ray diffraction and microtomographyMarcos Vinicius Colaço Gonçalves 13 October 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A urolitíase é um problema de escala mundial, que ocorre em todas as regiões, culturas e grupos raciais. A incidência desta doença vem aumentando ao redor do mundo e dados mostram que no Brasil estima-se que são afetados 5% da população com uma taxa de recorrência de 2,5%. Conhecer a composição mineral e estrutura interna dos cálculos é um passo importante para tentar entender melhor a fisiopatologia desta doença. Quatro cálculos urinários infecciosos, íntegros de grande volume (diâmetro maior que 20 mm), sendo dois provenientes da bexiga e dois de rins, obtidos cirurgicamente no setor de urologia do Hospital Universitário Pedro Ernesto (HUPE/UERJ) foram analisados usando microtomografia (μCT) e difração de raios X por policristais (DRXP). As imagens microtomográficas foram obtidas usando tubo de raios X microfoco na estação TomoLab e radiação síncrotron (SR-μCT) na linha de Física Médica, ambos no Laboratório Síncrotron Elettra, Trieste, Itália. As medidas de DRXP foram realizadas na linha de Difração de Raios X do Laboratório Nacional de luz Síncrotron, Campinas, Brasil. Para os cálculos de bexiga foram encontradas quatro fases cristalinas: estruvita (STV), oxalato mono (COM) e dihidratado (COD) e hidroxiapatita (HAp). Nos cálculos renais foram encontrados STV e HAp, sendo predominante a primeira fase cristalina. A quantidade de material amorfo (não-cristalino) foi maior que 60% da composição das amostras. A técnica convencional utilizada foi eficaz para análise dos cálculos urinários inteiros e possibilitou a visualização de estruturas internas sem interferência de procedimentos prévios de preparação da amostra. As análises de DRXP com fonte síncrotron aliadas ao método Rietveld foram determinantes para identificação e quantificação dos minerais presentes nas varias camadas das amostras. Pode-se constatar a complementaridade entre a μCT e a DRXP para caracterização microestrutural e mineralógica de cálculos urinários humanos. / Urolithiasis is a worldwide problem that afflicts all regions, cultures and ethnics groups. The incidence is increasing around the world and related data about Brazil estimate that affect 5% population with 2.5% recurrence rate. Knowledge of the quantitative mineralogy of urinary calculi is of fundamental importance for optimization of nephrolithiasis therapy and to prevent potential risk of recurrence. The urinary stones used in the present study were made available to us via normal surgery from patients admitted to the Hospital Universitário Pedro Ernesto (HUPE/UERJ). Structural and microstructural characterizations of four urinary calculi samples (RJ100, RJ101, RJ102 e RJ104) were determined by means of X-ray microtomography and powder diffraction. Conventional (μCT) and synchrotron radiation microtomography (SR-μCT) experiments were performed at the TOMOLAB station and SYRMEP (SYnchrotron Radiation on MEdical Physics) beamline, both at the Elettra Synchrotron Light Laboratory in Trieste (Italy), respectively. Synchrotron X-ray powder diffraction (XRPD) data were collected at the X-ray powder diffraction beamline of the National Synchrotron Light Laboratory (LNLS) in Campinas, Brazil. For the bladder stones, RJ100 and RJ104, the identified phases were struvite (STV), calcium oxalate monohydrate (COM) and dihydrate (COD) and calcium hydroxyapatite (HAp). The kidney stones RJ101 and RJ102 can be considered pure struvite stones. Moreover, the Rietveld refinement indicates the presence of more than 60 wt% of amorphous phase of all samples. The use of μCT scanning technology not only improves knowledge of internal structures of intact urinary calculi, but also allowed us to investigate efficiently specimens that run a particular risk of deformation or destruction from conventional preparation. Synchrotron X-ray powder profile-fitting structure refinement using the Rietveld method has proved to be a powerful tool in identifying and estimating the quantitative crystalline phase abundances present in the samples. This work demonstrated the capabilities of a combination ofμCT and XRP analyses for structural and microstructural characterizations of human urinary calculi samples. Moreover, the XRD data demonstrate that STV is the major constituent phase in all samples, which seems to be a tendency in Rio de Janeiro population. Clearly, there is a need for more studies on stone disease from Rio de Janeiro in order to isolate the fundamental reasons for the observed features of the kidney stones distribution.
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Caracterização de cálculos urinários humanos inteiros de rim e bexiga usando difração de raios X e microtomografia computadorizada / Characterization of human urinary calculi from bladder and kidney by X Ray diffraction and microtomographyMarcos Vinicius Colaço Gonçalves 13 October 2014 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A urolitíase é um problema de escala mundial, que ocorre em todas as regiões, culturas e grupos raciais. A incidência desta doença vem aumentando ao redor do mundo e dados mostram que no Brasil estima-se que são afetados 5% da população com uma taxa de recorrência de 2,5%. Conhecer a composição mineral e estrutura interna dos cálculos é um passo importante para tentar entender melhor a fisiopatologia desta doença. Quatro cálculos urinários infecciosos, íntegros de grande volume (diâmetro maior que 20 mm), sendo dois provenientes da bexiga e dois de rins, obtidos cirurgicamente no setor de urologia do Hospital Universitário Pedro Ernesto (HUPE/UERJ) foram analisados usando microtomografia (μCT) e difração de raios X por policristais (DRXP). As imagens microtomográficas foram obtidas usando tubo de raios X microfoco na estação TomoLab e radiação síncrotron (SR-μCT) na linha de Física Médica, ambos no Laboratório Síncrotron Elettra, Trieste, Itália. As medidas de DRXP foram realizadas na linha de Difração de Raios X do Laboratório Nacional de luz Síncrotron, Campinas, Brasil. Para os cálculos de bexiga foram encontradas quatro fases cristalinas: estruvita (STV), oxalato mono (COM) e dihidratado (COD) e hidroxiapatita (HAp). Nos cálculos renais foram encontrados STV e HAp, sendo predominante a primeira fase cristalina. A quantidade de material amorfo (não-cristalino) foi maior que 60% da composição das amostras. A técnica convencional utilizada foi eficaz para análise dos cálculos urinários inteiros e possibilitou a visualização de estruturas internas sem interferência de procedimentos prévios de preparação da amostra. As análises de DRXP com fonte síncrotron aliadas ao método Rietveld foram determinantes para identificação e quantificação dos minerais presentes nas varias camadas das amostras. Pode-se constatar a complementaridade entre a μCT e a DRXP para caracterização microestrutural e mineralógica de cálculos urinários humanos. / Urolithiasis is a worldwide problem that afflicts all regions, cultures and ethnics groups. The incidence is increasing around the world and related data about Brazil estimate that affect 5% population with 2.5% recurrence rate. Knowledge of the quantitative mineralogy of urinary calculi is of fundamental importance for optimization of nephrolithiasis therapy and to prevent potential risk of recurrence. The urinary stones used in the present study were made available to us via normal surgery from patients admitted to the Hospital Universitário Pedro Ernesto (HUPE/UERJ). Structural and microstructural characterizations of four urinary calculi samples (RJ100, RJ101, RJ102 e RJ104) were determined by means of X-ray microtomography and powder diffraction. Conventional (μCT) and synchrotron radiation microtomography (SR-μCT) experiments were performed at the TOMOLAB station and SYRMEP (SYnchrotron Radiation on MEdical Physics) beamline, both at the Elettra Synchrotron Light Laboratory in Trieste (Italy), respectively. Synchrotron X-ray powder diffraction (XRPD) data were collected at the X-ray powder diffraction beamline of the National Synchrotron Light Laboratory (LNLS) in Campinas, Brazil. For the bladder stones, RJ100 and RJ104, the identified phases were struvite (STV), calcium oxalate monohydrate (COM) and dihydrate (COD) and calcium hydroxyapatite (HAp). The kidney stones RJ101 and RJ102 can be considered pure struvite stones. Moreover, the Rietveld refinement indicates the presence of more than 60 wt% of amorphous phase of all samples. The use of μCT scanning technology not only improves knowledge of internal structures of intact urinary calculi, but also allowed us to investigate efficiently specimens that run a particular risk of deformation or destruction from conventional preparation. Synchrotron X-ray powder profile-fitting structure refinement using the Rietveld method has proved to be a powerful tool in identifying and estimating the quantitative crystalline phase abundances present in the samples. This work demonstrated the capabilities of a combination ofμCT and XRP analyses for structural and microstructural characterizations of human urinary calculi samples. Moreover, the XRD data demonstrate that STV is the major constituent phase in all samples, which seems to be a tendency in Rio de Janeiro population. Clearly, there is a need for more studies on stone disease from Rio de Janeiro in order to isolate the fundamental reasons for the observed features of the kidney stones distribution.
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Monitoramento e avaliação da emissão de dutos e fontes estacionarias de industrias ceramicas por meio de metodo potenciometrico e fluorescencia de raios X / Monitoring and evaluation of ducts and stationary source emissions from ceramic industries by potntiometry and X-ray fluorescence methodsFonseca, Roney Jose da 31 August 2007 (has links)
Orientador: Silvana Moreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T08:53:13Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: O objetivo deste trabalho foi monitorar e avaliar a emissão de fluoreto e de metais de dutos e fontes estacionárias de indústrias cerâmicas da região do Pólo Cerâmico de Santa Gertrudes (SP). Nos últimos anos houve um crescimento das empresas neste setor, causando reflexos ambientais nesta região responsável por 60% da produção de pisos esmaltados. O principal causador destes danos é o flúor na forma de fluoreto gasoso e ácido fluorídrico, comumente encontrado no solo e na argila utilizada na fabricação de pisos e artefatos cerâmicos. No período de 2004 a 2007 foram coletadas amostras dos gases emitidos por diversas indústrias cerâmicas desta região. Os compostos a base de flúor foram analisados por potenciometria e alguns metais pela técnica de fluorescência de raios X por reflexão total com radiação síncrotron. Altas concentrações de elementos como Cromo, Níquel e Chumbo foram observadas nas amostras analisadas e, em valores superiores aos permitidos pela legislação. No que se refere à emissão de fluoreto total foi verificado que 61,5% das empresas monitoradas apresentaram valores de emissão acima do permitido (5,0 mg/Nm3). Foi verificado ainda que o fluoreto foi emitido principalmente na forma de fluoreto gasoso. Desta forma a problemática ambiental na região de Santa Gertrudes não está associada apenas à emissão de flúor, mas também está relacionada à presença de metais pesados presentes em altas concentrações nas emissões atmosféricas provenientes do setor cerâmico / Abstract: The purpose of this work was monitoring and evaluation the emissions of fluoride and metals of ducts and stationary sources from ceramics industries of Santa Gertrudes region (SP). In recent years there had been a growth of companies in this sector, causing environmental repercussions in this region responsible for 60% of the production of porcelain tiles. The main cause of these damages is fluorine as fluoride gaseous and fluoridric acid, commonly found in soil and clay used in the manufacture of ceramic artifacts. During 2004 until 2007 gaseous samples were collected in different industries. The fluorine compounds were analyzed by potentiometry method and some metals by X-ray fluorescence analysis. High concentrations of Chromium, Nickel and Lead were observed in the samples and the values were higher than the permitted by the Brazilian legislation. In relation to fluoride emission 61,5% of the industries monitored showed values above the established by the legislation (5.0 mg/Nm3). In this way the environmental pollution in Santa Gertrudes region was not associated just to fluorine emission but also with the heavy metals present in high concentrations in the atmospheric emissions from stationary sources of ceramic industries / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
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Avaliação de metais pesados em emissões atmosfericas de industria automotiva por fluorescencia de raios X / Evaluation of the heavy metals in the atmospheric emissions of the automotive industry by SR-TXRFWeber Neto, Jose 31 August 2007 (has links)
Orientador: Silvana Moreira / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Civil, Arquitetura e Urbanismo / Made available in DSpace on 2018-08-11T18:03:07Z (GMT). No. of bitstreams: 1
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Previous issue date: 2007 / Resumo: A qualidade do ar está diretamente à qualidade de vida da sociedade. Nos últimos anos vários episódios de poluição nos grandes centros urbanos, bem como as doenças causadas pela baixa qualidade do ar têm feito com que os órgãos governamentais estabeleçam padrões de qualidade do ar e também para as emissões atmosféricas que geralmente são as responsáveis pela poluição atmosférica. O presente estudo tem como objetivo a determinação de metais pesados e outros elementos (Bário, Bromo, Cálcio, Chumbo, Cloro, Cobre, Cromo, Estrôncio, Ferro, Manganês, Níquel, Potássio, Silício, Titânio e Zinco), nos poluentes atmosféricos gerados em uma indústria automotiva localizada em Engenheiro Coelho no interior do estado de São Paulo. Os procedimentos adotados para a execução das amostragens e o preparo das amostras foram baseados nas normas definidas pela Companhia de Tecnologia de Saneamento Ambiental (CETESB) e, também pela Agência de Proteção Ambiental Americana (EPA). As análises foram realizadas pela técnica de Fluorescência de Raios X por Reflexão Total com Radiação Síncrotron (SR-TXRF) no Laboratório Nacional de Luz Síncrotron em Campinas (SP). Os resultados obtidos apresentaram concentrações na faixa de 30 mg/Nm³ para Zinco, Ferro, Bário, Cálcio e Potássio, enquanto que os outros elementos apresentaram concentrações próximas a 1 mg/Nm³. A técnica analítica apresentou limites de detecção bem inferiores (cerca de 1000 vezes) aos valores estabelecidos nas Resoluções CONAMA 264/1999 e SEMA 041/2002, que estabelecem valores máximos permitidos para emissões atmosféricas / Abstract: The air quality has a direct link with the life quality society, lately, a large number of cases of air pollution have been happening in the great urban centers, as well as diseases caused by the poor air quality. These facts have forced the government organs to create standards for the air regulations and also for the atmospheric emissions that generally are the main responsible for the air quality alterations. This study had as goal the determination of heavy metals and other elements (Barium, Bromine, Calcium, Lead, Chlorine, Copper, Chromium, Strontium, Iron, Manganese, Nickel, Potassium, Silicon, Titanium and Zinc) in the atmospheric pollutants generated by an automotive industry located in Engenheiro Coelho city, São Paulo State, Brazil. The sampling and sample preparation procedures were based on methods established by Company of Technology of Environmental Sanitation (CETESB L9.234) and also by the Environmental Protection Agency (EPA - Method 29). The analysis was performed at XRF Beamline (D09B-XRF) in the Synchrotron Light Source Laboratory (Campinas/SP). For zinc, iron, barium, calcium, potassium the values obtained were in the range of 30 mg/Nm³ and for other elements the concentrations were approximately 1 mg/Nm³. The analytical technique employed presented detection limits much smaller (1,000 times) than maximum permissive values established by Brazilian legislations (CONAMA 264/1999 and SEMA 041/2002) / Mestrado / Saneamento e Ambiente / Mestre em Engenharia Civil
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