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Darbo objektas – Kazlų Rūdos mokomosios miškų urėdijos, Šališkių girininkijos miškai, brandūs mišrūs derlingų drėgnų augaviečių medynai (iškirstos pagrindiniais plynais kirtimais biržės). Darbo tikslas – nustatyti dažniausiai miško inventorizacijos praktikoje (miškotvarkos darbų metu naudojami metodai, miškininkų gamybininkų miško urėdijose naudojami metodai ir moksliniuose tyrimuose naudojami metodai) naudojamų tūrio nustatymo metodų tikslumą ir išsiaiškinti jį lemiančias priežastis. Darbo metodai – atrankos, statistinių hipotezių tikrinimo ir vidurkių palyginimo bei dendrometrinis metodai. Darbo rezultatai. Atlikus medynų tūrio įvertinimą etalonu laikant ištisinio medžio matavimo metodą lyginant su sklypinės miškų inventorizacijos gautu tūriu pagal medžių rūšis paaiškėjo, kad didžiausi skirtumai yra beržo 8,2%, pušies 7,7 %, eglės 4,7 %, juodalksnio 4,2 %, uosio -1,7 %. Ištisinio medžių matavimo metu gautus tūrius lyginant su sklypinės miškų inventorizacijos gautais tūriais paaiškėjo, kad sklypinė miškų inventorizacija medžių tūrį biržėje didina vidutiniškai 21,5m³/ha. Ištisinio medžių matavimo metu gautus tūrius lyginant su pagaminta miško produkcija paaiškėjo, kad tūris atskirose miško sklypuose didinamas, bendra paklaida 16 miško sklypų sudaro iki 1 %. Gauti rezultatai parodė, kad tūrio tikslumui nustatyti įtakos turi medžių rūšinė sudėtis sklype, taksaciniai instrumentai, naudojami normatyvai. Reikia įvertinti tai, kad matuojant ištisai kiekvieną medį, gautas... [toliau žr. visą tekstą] / The object of the research – the forests of Kazlų Rūda educational forest office, Šališkės forrest office, cut in main cuttings. The main aim of the research: – to estimate the precision of the most frequent bulk evaluation methods and to find the reasons that determine it. Methods of the research – selection, statistic hypothesis check and average comparison. Results of the research. After performing a wood bulk evaluation keeping solid tree measurement as a standard, comparing with the bulk, found by parcel forest inventorization according to tree species, it emerged that the biggest differences are of the birch 8,2%, pine 7,7 %, fir 4,7 %, black alder 4,2 %, ash -1,7 %. The bulks found by solid trees measurement comparing with the bulks found by parcel forest inventorization, it emerged that parcel forest inventorization increases wood bulk in the stall 21,5m³/ha on the average. The bulks found by solid trees measurement comparing with forest production, it emerged that the bulk in separate forest parcels is increased, common bias in 16 forest parcels is up to 1%. The results showed that the varietal composition in the parcel, taxation instruments, used normatives have influence. It is needed to evaluate that measuring each tree throughout, we get a bulk precision that better reflects reality. But using selective trees measurement in the parcel, we can evaluate with enough precision and in short period of time.

L’objet de ce travail de thèse porte sur la synthèse originale en milieu fluide supercritique (FSC) de précurseurs « bulk » de catalyseurs d’hydrodésulfuration (HDS) à haute surface spécifique (SBET), destinés à l’HDS de composés soufrés réfractaires tels que le 4,6 diméthyldibenzothiophène (4,6¬ DMDBT). Ce projet a été réalisé en collaboration entre l'Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB-CNRS) et l'Instituto de Tecnología Química de Valencia (ITQ-CSIC) dans le cadre du réseau européen d’excellence Functional Advanced Materials and Engineering of Hybrids and Ceramics (FAMEnoe). Les études à l’ICMCB se sont portées sur l’optimisation des paramètres de synthèse en milieu FSC de NixCo1-xMoO4 (0 ≤ x ≤ 1) (précurseurs métalliques, solvant, température, pression). Des poudres de précurseurs « bulk » majoritairement composées de la phase hydratée (NiMoO4.0,75H2O) - phase la plus active en HDS - de composition contrôlée et pouvant atteindre près de 200 m2.g-1 ont été obtenues et caractérisées.Les propriétés catalytiques de ces précurseurs « bulk » après sulfuration ont ensuite été testées à l’ITQ sur la réaction de Deep-HDS d’un mélange modèle et d’une fraction pétrolière réelle. L’étude souligne plus particulièrement leurs meilleures capacités d’hydrogénation et de catalyse de l’HDS du 4,6 DMDBT que le catalyseur commercial utilisé comme référence dans ces travaux. / This work deals with an original synthesis using supercritical fluids (SCF) of “bulk” catalyst precursors of hydrodesulfurization (HDS) with high specific surface area (SBET) and dedicated to the HDS of refractive sulfur compounds such as 4,6 dimethyldibenzothiophene (4,6-DMDBT). This work was performed in collaboration between the Institut de Chimie de la Matière Condensée de Bordeaux (ICMCB-CNRS) and the Instituto de Tecnología Química de Valencia (ITQ-CSIC) within the Functional Advanced Materials and Engineering of Hybrids and Ceramics network of excellence (FAMEnoe).Studies performed at the ICMCB consisted in optimizing the parameters of the synthesis in SCF of NixCo1-xMoO4 (0 ≤ x ≤ 1) (metallic precursors, solvent, temperature, pressure). Powders of “bulk” precursors mainly consisting of the hydrated phase (NiMoO4.0,75H2O) - the most active phase in HDS - with controlled composition and SBET up to 200 m2.g-1 were obtained and characterized.The catalytic properties of those “bulk” precursors after sulfidation were then tested at the ITQ for the reaction of Deep-HDS of a model feedstock and a real feedstock. The experiments highlighted their better hydrogenation capacity and efficiency in catalyzing the HDS of 4,6 DMDBT than the commercial catalyst used as a reference in this work.

Ces travaux de recherche présentent une modélisation/Simulation du Test BCI (Bulk Current Injection) sous contrainte RTCA – DO 160, test de qualification des équipements très contraignant en termes de coûts et délais. Lors de sa réalisation, il présente aussi beaucoup de disparités dont il est parfois difficile d’identifier les sources et de les maîtriser lors du test avec une maquette physique. La simulation présente tout son intérêt dans l’étude de ces phénomènes (qui peuvent avoir un impact non moins significatif sur les résultats de test) mais aussi la répétabilité des essais.Dans un premier temps, une méthode de modélisation du couplage pince d’injection de courant et câbles est établie qui tient compte de l’évolution en fonction de la fréquence du noyau de ferrite du transformateur RF (Pince de courant) et des paramètres linéiques des câbles. Deux modèles sont principalement proposés dans ces travaux :- Un modèle générique, modèle circuit constitué uniquement d’éléments passifs RLC et élaboré (sous SPICE) à partir de la mesure des paramètres S. Ce modèle fait apparaitre la zone de couplage entre pince et câbles au secondaire.- Un modèle magnétique, macro-modèle développé sous le logiciel Flux2D. Les paramètres géométriques du modèle sont renseignés à partir de la connaissance des dimensions de la pince (diamètres intérieur /extérieur, longueur) et des câbles (diamètres/longueurs). Les paramètres physiques de la pince de courant particulièrement la perméabilité magnétique complexe du noyau de ferrite est obtenue à partir de la mesure du coefficient de réflexion au port d’entrée de la pince et extraction en post-traitement.Les validations dans le domaine fréquentiel ont été effectuées avec une bonne corrélation entre simulations et mesures dans la bande BCI [10 kHz – 400 MHz]. Ces résultats obtenus ont permis l'élaboration d'un modèle complet du test BCI (sous l’outil logiciel PAM-CEM/CRIPTE) qui tient compte d’un toron aéronautique complexe et de l’EST (Équipement Sous Test modélisé au laboratoire Ampère de Lyon). Il est constitué du générateur de perturbation (qui fait office de pince d’injection de courant), du modèle du toron de câbles (constitué de paires torsadées blindées, de paires non-blindées, …) et de l’EST (Équipement Sous Test) dans la bande [10 kHz – 400 MHz]. La bonne concordance entre simulations et mesures laisse présager une utilisation par les avionneurs ou équipementiers pour des études paramétriques concernant le test BCI (influence de la disposition des câbles, queue de cochon, longueur toron, disposition de l’EST par rapport au plan de masse, …) et/ou pour une virtualisation dans une phase de pré-qualification des équipements.Mots clés : CEM (Compatibilité ElectroMagnétique), Test BCI (Bulk Current Injection), Modélisation/Simulation, Norme aéronautique DO 160. / This work presents a modeling/simulation approach of BCI (Bulk Current Injection) test under constraint RTCA - DO 160. This qualification test of equipment is very constraining in terms of cost and deadline. During the test, there are also many disparities for which it is difficult to identify sources (and control them) with a physical test setup. The simulation is of interest in the study of phenomena (which can have negative impacts on test results) but also the repeatability of tests.First, a method of modeling for the probe/cables coupling is established which takes into account the variation with frequency of the RF transformer (current probe) of the magnetic ferrite core and the linear parameters of cables (skin/ proximity effects). Two models are proposed in this work:- A generic model which is made up solely of passive elements RLC and elaborated (with SPICE software) from the measurement of S-parameters. It shows the coupling zone between probe and cables (secondary winding).- A magnetic macro-model developed with the Flux2D software. Its geometrical parameters are defined from dimensions of the probe (inner/outer diameter, length) and cables (diameters / length). Physical parameters of the current probe, particularly the complex magnetic permeability of the ferrite core, are obtained from measurement of the S-parameter at the input port of the probe and post-treatment extraction.Frequency domain validations were performed with a good correlation between simulations and measurements in the BCI band ([10 kHz - 400 MHz]).These results led to the development of a complete virtual BCI test (with PAM-CEM / CRIPTE software), which take into account an aeronautic complex harness and a DUT (Device Under Test which is modeled at Ampère laboratory). It consists of disturbance generator, harness model (consisting of shielding twisted cables, no shielding cables, etc.) and DUT (Device Under Test) in the band [10 kHz - 400 MHz].The good correlation between simulations and measurements suggests a use by the aircraft manufacturers or equipment manufacturers for parametric studies about BCI test (uncertainties related to cable positions, pigtail, cable length, DUT position with respect to the ground plane, ...) and /or for virtualization in a pre-qualification phase of the equipment.Keywords: EMC (ElectroMagnetic Compatibility), BCI (Bulk Current Injection) test, Modeling/Simulation, DO 160 aeronautic standard.

Fundação de Amparo a Pesquisa do Estado de Minas Gerais / PbS quantum dots has been grown in oxide glasses by two distinct methodologies according to the dopants, using the fusing method at 1200ºC. The host glass matrices used were SNAB (SiO2.Na2CO3.Al2O3.B2O3) and SNABP (SiO2.Na2CO3.Al2O3.B2O3.PbO2), with PbS bulk and S (sulphur) added as dopants, respectively. Thermal treatments were applied in a systematic way in order to allow a controlled growth of quantum dots. Different experimental techniques were realized in order to study the growth kinetic of dots as a function of thermal treatment times and dopant concentrations. It was analyzed thermal properties of the glass matrices by Calorimetry Scanning Diferencial (DSC). Many techniques have allowed discussion of the optical properties by Optical Absorption (OA) and Photoluminescence (PL), morphologic properties by Atomic Force Microscopy (AFM), and structural properties by X-Ray Diffractometry (DRX) of the nanocrystals. Qualitative and quantitative analyse of the chemical composition of the samples has been possible by spectrometry of Fluorescence of Raios-X (FRX). Using the ] 4 4 [ . × p k r r method we were able to estimate the avarage diameter of the PbS quantum dots. Calculations of dispersion sizes of PbS quantum dots, from the AO bands, has been presented. We have found the dependence between the quantum dot gap and the dopant concentrations. The relation between the Stokes Shift and the average size of the PbS quantum dots was also presented. Through the previous results, we have defined the methodology referring the host glass matrix SNABP with S bulk added as the most favorable to the growth PbS quantum dots with low size dispersion. / Pontos Quânticos de PbS foram sintetizados em vidros à base de óxidos, a partir duas metodologias distintas quanto a dopagens, pelo método da fusão a 1200ºC. As matrizes vítreas hospedeiras utilizadas foram: SNAB (SiO2.Na2CO3.Al2O3.B2O3) e SNABP (SiO2.Na2CO3.Al2O3.B2O3.PbO2), e os dopantes adicionados à elas foram PbS bulk e S (enxôfre), respectivamente. Tratamentos Térmicos variados e adequados foram efetuados nestas amostras para permitir o crescimento controlado dos pontos quânticos de PbS. Com o objetivo de estudar e acompanhar a cinética de crescimento destes pontos em função dos tempos de tratamentos térmicos e das variadas concentrações de dopantes, foram efetuadas várias técnicas de caracterizações. Estas permitiram análises das propriedades térmicas dos vidros por Calorimetria Exploratória Diferencial (DSC); ópticas, por Absorção Óptica (AO) e Fotoluminescência (PL); morfológicas, por Imagens de Microscopia de Força Atômica (AFM); e estruturais, por Difratometria de Raios-X (DRX) dos referidos nanocristais. Análises qualitativas e quantitativas das composições químicas das amostras sintetizadas neste trabalho foram possíveis através da técnica de espectrometria de Fluorescência de Raios-X (FRX). Com o auxilio do método ] 4 4 [ . × p k r r , foi possível estimar o diâmetro médio dos pontos quânticos de PbS. Cálculos de dispersão de tamanhos ξ a partir da largura a meia altura (W) das bandas de AO e discussões sobre a dependência de energia e o tamanho médio dos pontos quânticos foram apresentados e discutidos. Mostrouse graficamente a relação de dependência entre o Gap dos pontos quânticos e as concentrações de dopantes adicionados às matrizes vítreas. Apresentou-se de forma gráfica a relação entre o deslocamento Stokes e o tamanho médio dos pontos quânticos de PbS. A partir de análises dos resultados obtidos, definiu-se então a metodologia correspondente à matriz SNABP dopada com S bulk como sendo a mais favorável para a formação e crescimento dos pontos quânticos de PbS com menor dispersão de tamanhos entre si. / Mestre em Física

The achievement of predictable and long lasting adhesive restorations in posterior teeth have always been a major objective of studies in the context of materials and techniques development. The use of bulk fill composites could provide better outcomes, but it is important to assess their physico-mechanical properties, responsible for their clinical behavior. The purpose of the present study was to assess the mechanical and physical properties of bulk fill composites. The composites were divided into 2 groups according to their viscosity. For low viscosity composites, the present study assessed: Surefill SDR flow (SDR), X-tra Base (XB), Filtek Bulk Fill Flowable (FBF), and Filtek Z350XT Flow (Z3F- control); and for high viscosity composites: Tetric Evo Ceram Bulk Fill (TBF), X-tra Fil (XF), Filtek Bulk Fill (FBP), Admira Fusion x-tra (ADM) and Filtek Z350 XT (Z3XT- control). Composites were assessed through shrinkage stress test (using 12 and 24mm3 of composite in a custom device adapted in an Universal Testing Machine); volumetric shrinkage (using 64mm3 of composite placed on a Teflon mold and scanned in a micro computed tomography/CT); Youngs modulus (through a 3-point bending test device adapted in an Universal Testing Machine); microhardness and depth of cure tests (using longitudinal Knoop microhardness). All data was evaluated regarding their homogeneity using Shapiro-Wilk test. For polymerization stress, 3-way Variance Analysis (ANOVA) was used. Considering Volumetric Shrinkage, Youngs Modulus, Microhardness and Depth of Cure, one-way ANOVA was used. All ANOVA tests were followed by Tukeys test and 5% was adopted as significance level. Shrinkage stress test with 12mm3 showed SDR, TBF and XF generating the lowest stress after 300s, followed by other high viscosity composites (ADM, FBF, XB and FBP/Z3XT). The regular low viscosity composite (Z3F) generated the highest stress for all assessed times. Considering the same test, with 24mm3, after 300s, SDR, FBP and ADM generated similar stress, followed by TBF and XF. Low viscosity bulk fill composites generated lower stress than Z3F. Considering Youngs modulus, low viscosity composites (SDR, FBF, XB and Z3F) showed the lowest values, followed by ADM and TBF. The other high viscosity composites (Z3XT, FBP and XF) showed the highest values. For microhardness test, all low viscosity composites showed lower values (FBF being the lowest). For high viscosity composites, Z3XT showed the highest values, followed by XF, FBP/TBF and ADM. Assessing depth of cure, regular composites showed lower values when compared with bulk fill composites. All bulk fill composites showed adequate depth of cure over 4.5mm (microhardness 80% of initial reading). SDR and XB showed the highest depth of cure. All high viscosity bulk fill composites generated lower volumetric shrinkage than regular composites. All low viscosity bulk fill composites showed similar volumetric shrinkage when compared to the regular composites (Z3F and Z3XT). Bulk fill composites show characteristics that allow their use in larger increments (i.e. volumetric shrinkage and polymerization stress similar or lower when compared with regular composites). Nonetheless, the mechanical properties of bulk fill composites were widely variable, being important to individually assess each material previously to its clinical application. / A obtenção de restaurações adesivas previsíveis e duradouras em dentes posteriores sempre foi objetivo de estudos na área de desenvolvimento de materiais e técnicas. O uso de resinas compostas do tipo bulk fill pode possibilitar melhores resultados, porém é importante o estudo de suas propriedades físico-mecânicas, responsáveis por seus comportamentos clínicos. O objetivo do presente estudo foi o de avaliar as propriedades físicas e mecânicas das resinas bulk fill. As resinas foram divididas em 2 grupos de acordo com sua viscosidade. Para resinas de baixa viscosidade, o presente estudo avaliou: Surefill SDR flow (SDR), X-tra Base (XB), Filtek Bulk Fill Flowable (FBF) e Filtek Z350XT Flow (Z3F-controle); e, para alta viscosidade: Tetric Evo Ceram Bulk Fill (TBF), X-tra Fil (XF), Filtek Bulk Fill (FBP), Admira Fusion x-tra (ADM) e Filtek Z350 XT (Z3XT-controle). As resinas foram avaliadas em relação à tensão de polimerização (utilizando 12 e 24mm3 de resina adaptadas em um dispositivo adaptado a uma máquina de testes universal); contração volumétrica (utilizando 64mm3 de resina composta inserida em um molde de Teflon e escaneada em um micro-tomógrafo/CT), modulo de Young (através de um dispositivo de flexão em 3 pontos adaptado a uma máquina de testes universal), microdureza e profundidade de polimerização (utilizando microdureza Knoop). Todos os resultados foram avaliados em relação à homogeneidade utilizando o teste de Shapiro-Wilk. Para avaliação da tensão de polimerização, foi empregada a Análise de Variância (ANOVA) a 3 critérios. Para as analyses de contração volumétrica, Módulo de Young, microdureza e profundidade de polimerizaçao, ANOVA a um critério foi empregada. Todas as Análises de Variância foram seguidas pelo teste de Tukey e 5% foi adotado como nível de significância. A tensão de polimerização com 12mm3 demonstrou que SDR, TBF e XF geraram valores significantemente mais baixos após 300s, seguidas por outras resinas de alta viscosidade (ADM, FBF, XB e FBP/Z3XT). A resina convencional de baixa viscosidade (Z3F) gerou valores de tensão significantemente mais elevados para todos os tempos avaliados. Considerando o mesmo teste, com 24mm3, após 300s, SDR, FBP e ADM geraram valores estatisticamente inferiores, seguidas por TBF e XF. As resinas bulk fill de baixa visocidade geraram menor tensão de polimerização que a Z3F. Considerando o modulo de Young, resinas de baixa viscosidade (SDR, FBF, XB e Z3F) apresentaram valores significantemente inferiores, seguidas por ADM e TBF. As outras resinas de alta viscosidade (Z3XT, FBP e XF) apresentaram valores significantemente mais elevados. Para o teste de microdureza, todas as resinas de baixa viscosidade apresentaram valores inferiores (FBF apresentou o menor). Para as resinas de alta viscosidade, Z3XT apresentou os valores mais elevados, seguida por XF, FBP/TBF e ADM. Para profundidade de polimerização, resinas compostas convencionais apresentaram valores signifixantemente mais baixos quando comparadas com resinas bulk fill. Todas as resinas bulk fill apresentaram profundidade de polimerização adequada até pelo menos 4,5mm (microdureza 80% da leitura inicial/superfície). SDR e XB apresentaram os valores mais altos de profundidade de polimerização. Todas as resinas bulk fill de alta viscosidade geraram menor contração volumétrica que resinas compostas convencionais. Todas as resinas bulk fill de baixa viscosidade apresentaram contração volumétrica similar às resinas convencionais (Z3F e Z3XT). Resinas compostas bulk fill apresentaram características que possibilitam sua indicação para serem empregadas em grandes incrementos (contração volumétrica e tensão de polimerização similar ou inferiores às resinas convencionais, além de maior profundidade de polimerização). No entanto, as propriedades mecânicas variaram grandemente entre as resinas estudadas sendo importante uma avaliação individual de cada material previamente ao seu uso clínico.

Diante da evolução da composição das resinas compostas e do lançamento de compósitos do tipo bulk fill, faz-se necessário o estudo do desempenho dessa nova classe de materiais. Para isso, o presente estudo teve como objetivo avaliar propriedades como grau de conversão (GC) , dureza Knoop (KHN), resistência à flexão (RF) e tenacidade à fratura (KIC) de sete compósitos bulk fill (EverX Posterior, EXP; Filtek Bulk Fill Flow, FBFF; Fill-Up!, FU; SonicFill, SF; Surefil SDR, SDR; Tetric EvoCeram Bulk Fill, TECBF; Venus Bulk Fill, VBF) e um compósito nanohíbrido convencional (Charisma Diamond, CD). De forma complementar, foi realizado tratamento térmico a 170 °C por 10 minutos para melhor compreensão do comportamento desses materiais quanto ao potencial de conversão e à indução de tensões na interface carga/matriz. A avaliação do GC (n=3) foi realizada através de espectroscopia FTIR, a leitura da dureza Knoop foi realizada nas superfícies do topo e da base (n=3), e os ensaios de RF de três pontos (n=10) e KIC (n=10) em máquina de ensaios universais. Os resultados obtidos foram submetidos à analise de variância (complementados pelo teste de Tukey) ou teste Kruskal-Wallis, com nível de significância de 5%. A análise do GC (%) revelou diferença entre os materiais testados, sendo que todas as resinas bulk fill apresentaram valores maiores que a resina convencional: SF (75,7) > VBF (66,7) = EXP (66,4) = SDR (62,8), sendo esta também semelhante a FU (60,0); FU, TECBF (56,6), FBFF (56,6) e CD (54,5) apresentaram conversão semelhante. Os valores de KHN variaram de acordo com o material e com a superfície: apenas SF apresentou KHN semelhante (na superfície do topo) a CD, entretanto não foi possível realizar a leitura da superfície da base deste último material; SF, TECBF e FBFF apresentaram valores de KHN diferentes nas superfícies topo e base; EXP, FU, SDR e VBF mantiveram os valores de dureza do topo semelhantes à superfície da base. Para a RF (MPa), os resultados variaram de acordo com o material: EXP (122,54) = SF (101,09) = CD (99,15), sendo estes dois últimos semelhantes a FU (83,86) e TECBF (82,71), os quais não diferiram da resina SDR (65,18); esta última também mostrou comportamento semelhante a FBFF (60,85) e VBF (59,90). Quanto ao KIC (MPa.mm0,5), EXP (3,35) apresentou o maior valor, semelhante a SF (2,42), que por sua vez também foi igual ao compósito convencional CD (2,01); CD apresentou KIC semelhante a SDR (1,74); SDR = VBF (1,59) = TECBF (1,57); TECBF, FU (1,54) e FBFF (1,37) apresentaram valores semelhantes. Na dependência do material, o tratamento térmico aumentou os valores dos parâmetros estudados, apontando limitações da reação de polimerização dos compósitos estudados. Com base nos resultados obtidos, podese concluir que: resinas bulk fill apresentam elevado GC, superior à resina convencional estudada; a nova classe de materiais restauradores é capaz de polimerizar em profundidade e alguns materiais apresentam KHN semelhantes no topo e na base de espécimes de 4 mm de profundidade; RF e KIC variaram de acordo com o material, e o compósito EXP apresentou os maiores valores para ambos os testes. / Facing the evolution of the resin composites and the release of the bulk-fill composite type, it is necessary to study the performance of this new class of materials. For this, the present study aimed to evaluate properties such as degree of conversion (DC), Knoop hardness (KHN), flexural strength (FS) and fracture toughness (KIC) of seven bulk-fill composites (EverX Posterior, EXP; Filtek Bulk Fill Flowable, FBFF; Fill-Up!, FU; SonicFill, SF; Surefil SDR, SDR; Tetric EvoCeram Bulk Fill, TECBF; Venus Bulk Fill, VBF) and a conventional nanohybrid composite (Charisma Diamond, CD). Complementarily, heat treatment was performed at 170 °C for 10 minutes for better understanding the behavior of these materials. Evaluation of DC (n=3) was performed by FTIR spectroscopy, the evaluation of Knoop hardness was made on the top and bottom surfaces (n=3), and three point bending test (n=10) and KIC (n=10) were evaluated on a universal testing machine. The results were submitted to analysis of variance (complemented by Tukey test) or Kruskal-Wallis test with 5% significance level. Analysis of DC (%) revealed differences between tested materials, and all bulk-fill resins had higher values than the conventional resin: SF (75.7) > VBF (66.7) = EXP (66.4) = SDR (62.8), which was also similar to FU (60.0); FU, TECBF (56.6), FBFF (56.6) and CD (54.4) showed similar conversion. KHN values showed variations according to the material and the surface: only SF showed a similar KHN (on the top surface) to CD, however it was not possible to read the bottom surface of this latter material; SF, TECBF and FBFF presented different KHN values on the top and bottom surfaces; EXP, FU, SDR and VBF maintained top and bottom similar hardness values. For FS (MPa), the results varied according to the material: EXP (122.54) = SF (101.09) = CD (99.15), the latter two being similar to FU (83.86) and TECBF (82.71), which did not differ from SDR resin (65.18); the latter showed similar behavior to FBFF (60.85) and VBF (59.90). As for KIC (MPa.mm0.5), EXP (3.35) had the highest value, similar to SF (2.42), which in turn was also equal to the conventional composite CD (2.01); CD presented KIC similar to SDR (1.74); SDR = VBF (1.59) = TECBF (1.57); TECBF, FU (1.54) and FBFF (1.37) were similar. Depending on the material, heat treatment increased the values of the parameters, pointing limitations of polymerization reaction of the studied composites. Based on these results, it can be concluded that: bulk fill resins have high DC, higher than the conventional resin studied; the new class of restorative materials is capable of polymerizing in depth and some materials exhibited similar KHN at the top and bottom surfaces of 4 mm depth specimens; FS and KIC varied according to the material, and the EXP composite showed the highest values for both tests.

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Zur richtigen Auslegung von fördertechnischen Anlagen in verschiedenen Industriezweigen, insbesondere in Häfen, ist es notwendig, die Arbeitsparameter der Schüttgutfördermaschinen zu kennen. Da die komplexe Bewegung des Materials im Senkrechtschneckenförderer (SSF) eine analytische Auslegung des Fördersystems verhindert, werden hier (semi-)empirische Modelle verwendet. Für eine umfassende Analyse der Transportvorgänge in SSF wurde am Institut für Aufbereitungsmaschinen der TU Freiberg im Rahmen der vorliegenden Arbeit ein Versuchsstand mit einem industriellen SSF konzipiert und gebaut, an dem der Transport von sieben Arten von Schüttgütern mit einer Schneckendrehzahl von 50 bis 320 1/min untersucht wurden. Anhand einer Literaturrecherche wurde ebenso der Einfluss des Aufgabeorts auf die Arbeitsparameter überprüft. Die erhaltenen Ergebnisse wurden statistisch ausgewertet und mit Hilfe derer eine semi-empirische Formel zur Auslegung anderer SSF entwickelt. Darüber hinaus wurden diverse Phänomene beim Transport unterschiedlicher Schüttgüter beobachtetet und in der vorliegenden Arbeit analysiert.:Inhaltsverzeichnis Abkürzungsverzeichnis Symbolverzeichnis 1 Einleitung 2 Wissenschaftlich-technische Grundlagen zur Förderung mit dem Senkrechtschneckenförderer 2.1 Charakterisierung der Fördermaterialien 2.1.1 Stoffarten 2.1.2 Physikalische Eigenschaften 2.1.2.1 Schüttgutdichten 2.1.2.2 Böschungswinkel 2.1.2.3 Reibungskoeffizienten 2.1.2.4 Systembedingte Schüttguteffekte 2.1.3 Granulometrie (Kornform- und Korngrößenverteilung) 2.1.4 Feuchtigkeit 2.2 Geometrie und Konstruktion des Senkrechtschneckenförderers 2.2.1 Aufgabeort mit Aufgabevorrichtung 2.2.2 Förderteil 2.2.3 Abgabeort 2.2.4 Spaltgeometrie und Spalteffekte 2.2.5 Lagerung der Welle 2.2.6 Antrieb 2.3 Einfluss des Förderprozesses auf die Fördermaterialien 2.4 Charakterisierung des Systemverhaltens von Senkrechtschneckenförderern 2.4.1 Kinematik und Dynamik der Einzelkörner in einem Senkrechtschneckenförderer 2.4.2 Modelle und Berechnungen der Betriebsparameter 2.4.2.1 Analytische Modelle 2.4.2.2 Semiempirische und empirische Modelle 3 Präzisierung der Aufgabenstellung 3.1 Systemanalyse des Senkrechtschneckenförderers 3.2 Folgerungen für die experimentellen Untersuchungen 3.3 Folgerungen für die Auslegungsmodellierung von Senkrechtschneckenförderern 3.4 Erweiterung des Senkrechtschneckenförderer-Systems um die Zuführeinrichtung 4 Experimentelle Untersuchungen für Auslegungsmodelle von Senkrechtschneckenförderern 4.1 Beschreibung der Versuchsdurchführung zur Erstellung einer Datenbank 4.1.1 Versuchsprogramm 4.1.2 Bestimmung der Stoffeigenschaften der untersuchten Materialien 4.1.2.1 Korngrößenanalyse 4.1.2.2 Materialdichte 4.1.2.3 Böschungswinkel 4.1.3 Versuchsablauf zur Bestimmung der Betriebsparameter 4.2 Beschreibung des Versuchsstandes 4.2.1 Aufbau und Konstruktion der Versuchsanlage 4.2.2 Variation der Versuchsparameter 4.2.3 Messeinrichtungen 4.3 Vorstellung und Beschreibung der Versuchsergebnisse 4.3.1 Gemessene Stoffeigenschaften 4.3.2 Analyse der Ergebnisse mit einseitiger Materialzuführung 4.3.2.1 Materialdurchsatz 4.3.2.2 Leistungsbedarf 4.3.2.3 Spezifischer Leistungsbedarf 4.3.2.4 Weitere Erkenntnisse aus den Untersuchungen mit einseitiger Materialzuführung 4.3.3 Analyse der Ergebnisse mit allseitiger Materialzuführung 4.3.3.1 Materialdurchsatz 4.3.3.2 Leistungsbedarf 4.3.3.3 Spezifischer Leistungsbedarf 4.3.3.4 Weitere Erkenntnisse aus den Untersuchungen mit allseitiger Materialzuführung 5 Auslegungsmodelle von Senkrechtschneckenförderern 5.1 Analytische Betrachtungen 5.1.1 Volumendurchsatz 5.1.2 Leistungsbedarf 5.2 Vorschläge für die Modellübertragung auf reale Senkrechtschneckenförderer 5.2.1 Einfluss von Durchmesserunterschieden auf den Volumendurchsatz 5.2.2 Einfluss von Durchmesserunterschieden auf den Leistungsbedarf 5.2.3 Einfluss von Drehzahlunterschieden auf den Volumendurchsatz 5.2.4 Einfluss von Drehzahlunterschieden auf den Leistungsbedarf 5.2.5 Einfluss von Förderhöhenunterschieden auf den Leistungsbedarf 5.3 Anwendungsbeispiel des Auslegungsmodells 6 Einführung zu einer Konstruktionssystematik für Zuführgeräte von Senkrechtschneckenförderern 7 Zusammenfassung 8 Literaturverzeichnis Anlagenverzeichnis

Les flux turbulents à l’interface air-mer représentent le lien entre l’océan et l’atmosphère et jouent donc un rôle majeur dans le système climatique. Dans les modèles de climat, les processus turbulents sont des processus sous-maille, non résolus explicitement, et doivent donc être paramétrés. Ils sont estimés à partir des variables d’états atmosphériques et océaniques au moyen de modèles mathématiques qu’on nomme « paramétrisations bulk ». Ce travail de thèse a pour objectif de caractériser et comprendre les liens entre la représentation des flux turbulents à l’interface air-mer et le fonctionnement d’un modèle de climat à différentes échelles de temps dans les régions tropicales. Pour étudier ces liens, j’ai développé une stratégie de modélisation utilisant un modèle 1D atmosphérique (SCM), un modèle de circulation générale océanique (OGCM) où atmosphérique (AGCM) et un modèle couplé (GCM). L’analyse des simulations SCM permet d’étudier la réponse directe d’un modèle à la modification de la paramétrisation des flux turbulents. On montre que cette dernière régule la quantité d’eau, d’énergie et de quantité de mouvement disponible pour le système et donc son fonctionnement. Elle représente plus de 60% des différences de flux de chaleur latente simulées entre deux modèles de climat dans les périodes convectives. L’impact spatial de la paramétrisation des flux turbulents est étudié au travers des simulations AGCM. Elles mettent en évidence le lien entre la paramétrisation, son effet sur les gradients d’humidité et de température à grande échelle, et donc son influence sur la circulation atmosphérique. L’étude des simulations OGCM souligne quant à elle le rôle principal du vent pour le fonctionnement des océans tropicaux. Si le vent pilote les variations de SST dues à son impact sur la dynamique océanique et principalement sur le sous-courant équatorial, l’humidité, la température et les flux radiatifs n’influencent quant à eux que la surface océanique et sont donc d’une moindre importance. Enfin, l’analyse des simulations GCM met en évidence les rétroactions et l’ajustement engendrés par la modification des flux turbulents. Lors du couplage des deux composantes l’océan agi comme un tampon et absorbe la modification des flux turbulents ce qui entraine une modification de la SST. L’ajustement qui se produit entraine une modification des variables atmosphériques qui amène à un nouvel état d’équilibre du système. La paramétrisation des flux turbulents de surface agit au premier ordre sur l'équilibre énergétique d'un modèle couplé et peut donc amener à des climats simulés différents. Cette étude étant centrée sur les tropiques, une perspective intéressante serait d’étendre l’étude de la représentation des flux turbulents à d’autres échelles spatio-temporelles (i.e. zones extratropicales/fréquence journalière). Cela permettrait de valider le fonctionnement systématique des paramétrisations définies dans cette thèse à l’échelle globale. / The turbulent fluxes at the air-sea interface represent the link between the ocean and the atmosphere and therefore play a major role in the climate system. In climate models, turbulent processes are subgrid scale processes, not explicitly resolved, and must therefore be parameterized. They are estimated from atmospheric and oceanic state variables using mathematical models called “bulk parameterizations”. This thesis aims to characterize and understand the links between the representation of turbulent fluxes at the air-sea interface and the behavior of a climate model at different time scales in tropical regions. To study these links, I developed a modeling strategy using an atmospheric 1D model (SCM), an oceanic (OGCM) or atmospheric (AGCM) general circulation model and a coupled model (GCM). The analysis of SCM simulations allows us to study the direct response of a model to modifications of the turbulent fluxes parameterization. It is shown that it regulates the amount of water, energy and momentum available to the system and therefore its behavior. It can thus represent more than 60% of simulated latent heat flux differences between two climate models in convective periods. The spatial impact of the parameterization of turbulent fluxes is studied through AGCM simulations. They highlight the link between parameterization, its effect on large-scale moisture and temperature gradients, and thus its influence on atmospheric circulation. The study of OGCM simulations underlines the main role of the wind for the behavior of the tropical oceans. If the wind drives changes in SST due to its impact on ocean dynamics and mainly on the equatorial undercurrent, humidity, temperature and radiative flux only influence the ocean surface and are therefore of lesser importance. Finally, the analysis of GCM simulations highlights the feedbacks and the adjustment generated by the modification of turbulent fluxes. When coupling the two components, the ocean acts as a buffer and absorbs the modification of the turbulent fluxes, which leads to a modification of the SST. The adjustment that occurs causes a modification of the atmospheric variables which leads to a new state of equilibrium of the system. The parameterization of surface turbulent fluxes acts at first order on the energy equilibrium of a coupled model and can therefore lead to different simulated climate state. Since this study is focused on the tropics, an interesting perspective would be to extend the study of the turbulent fluxes representation to other spatio-temporal scales (i.e. extra-tropical areas / daily frequency). This would make it possible to validate the systematic behavior of the parameterizations defined in this thesis on a global scale.