O emprego de pavimentos permeáveis tem se tornado cada vez mais necessário como medida compensatória para amortecer as vazões de pico e atenuar os impactos gerados pelas chuvas torrenciais em áreas altamente urbanizadas. Dentre os materiais convencionalmente adotados como revestimento permeável no contexto nacional destacam-se os blocos de concreto intertravados (BCI) e o asfalto poroso. No entanto, internacionalmente, existem materiais alternativos que podem apresentar permeabilidade igual ou até mesmo superior. Sob esse prisma, convém destacar o uso dos blocos de concreto articulados (BCA), recentemente adotados nos Estados Unidos e na Coréia do Sul, cuja capacidade de infiltração vem mostrando-se bastante promissora. Diferentemente dos blocos intertravados, os BCA foram projetados para trabalhar em conjunto, já que são interconectados por meio do encaixe das articulações unidirecionais de cada peça, sobrepostas umas às outras, dispensando assim o uso de material de rejunte, o que por sua vez aumenta a permeabilidade do revestimento. Contudo, embora o desempenho hidráulico aparente ser eficaz, questiona-se se o pavimento de blocos de concreto articulados (PBCA) comporta-se de forma igualmente satisfatória em termos estruturais. Nesse sentido, visando avaliar o desempenho estrutural e hidráulico de um pavimento permeável de BCA, foi construída uma pista experimental (20 x 5 m) no Campus da USP, adotando-se dois tipos de base, uma de agregado reciclado (RCD) e outra de agregado natural (brita 1). Na análise estrutural utilizaram-se como parâmetros de avaliação as deflexões máximas obtidas via FWD (Falling Weight Deflectometer), a eficiência de transferência de carga (LTE - Load Transfer Efficiency) e por fim, os módulos de resiliência retroanalisados para cada camada. Ademais, a pesquisa ainda avaliou a influência da presença de fissuras ou trincas nos blocos no desempenho estrutural do pavimento, já que acabaram tornando-se recorrentes em ambas as seções avaliadas. Já na avaliação hidráulica, monitorou-se a taxa de infiltração in situ ao longo de quase vinte meses. Complementarmente, foram realizadas ainda avaliações laboratoriais dos materiais empregados e funcionais do pavimento. A análise estrutural indicou que o sentido articulado do BCA obteve respostas estruturais nitidamente melhores que o sentido não articulado em termos de módulo de resiliência, deflexões máximas e LTE, evidenciando que de fato as articulações conferem intertravamento ao pavimento, próximo ao propiciado pela areia de rejunte no BCI. A base de RCD por apresentar uma distribuição granulométrica mais bem distribuída do que a brita 1, também obteve melhores resultados. Já a presença de trincas ou fissuras nos blocos não acarretou comprometimento no desempenho estrutural da pista experimental, devido ao baixo grau de severidade da maioria das patologias encontradas, como atestou o levantamento funcional, cuja classificação indicou um pavimento em boas condições de serventia. No que diz respeito ao desempenho hidráulico, o pavimento apresentou um desempenho adequado em termos de capacidade de infiltração. Apesar da perda progressiva estimada em 20% ao ano, as taxas de infiltração in situ mantiveram-se acima de 10-3 m/s em todos os ensaios realizados, sendo, portanto, superior à maioria dos revestimentos permeáveis tradicionalmente utilizados como os blocos intertravados e a camada porosa de atrito, conforme descritos pela literatura. / Pervious pavements have become increasingly fundamental as a compensatory measure to attenuate peak flows and to mitigate the impacts generated by torrential storm water in highly urbanized areas. Among the usual materials applied in permeable surface layers, it is possible to highlight the interlocking concrete blocks (ICB) and the porous asphalt. However, internationally, there are alternative materials that are able to present a higher permeability. In this sense, the use of articulated concrete blocks (ACB) needs to be stressed. Recently adopted in United States of America and South Korea, ACB has presented promising infiltration rates. Unlike the ICB, the ACB was designed to work as an integrated framework due to the presence of articulated joints in one of the block directions, which allows discarding the jointing sand and as result, increases water infiltration. Nevertheless, although the pavement hydraulic performance seems to be successful, there are some doubts about the structural behavior. Thereby, aiming at evaluating the hydraulic and structural performance of an unidirectionally articulated concrete block pavement, a pavement experimental section (20 x 5 meters) was constructed at the University of São Paulo Campus. Two types of different bases were applied, namely recycled concrete aggregate (RCA) and natural aggregate. The structural assessment took into account the maximum deflection measurements, the load transfer efficiency (LTE) and the backcalculated elastic moduli of each layer. In addition, this work also evaluated the structural influence caused by the presence of damaged pavers, since it became a recurring problem. Regarding the hydraulic evaluation, the surface infiltration rate was monitored over twenty months after the pavement construction. Furthermore, functional and laboratorial analyses were carried out in order to check the structure serviceability level. The structural results indicated clearly that the articulated block side had better performance than the non-articulated block side in terms of elastic moduli, maximum deflections measurements and LTE, confirming the interlocking efficiency generated by the block shape, comparable to that one provided by the jointing sand in ICB. As the recycled aggregate was characterized by a more well graded particle size distribution than the natural aggregate, the RCA base also presented better structural responses. The presence of damaged blocks did not compromise the pavement structural performance, since the degree of severity was low, as verified by the functional evaluation, which showed a pavement in good conditions. Finally, concerning the hydraulic results, the pavement presented a high infiltration capacity. Even though an infiltration loss of about 20% per year has been detected, the infiltration rate remained greater than 10-3 m/s for all tests performed, being considerably higher than those found in pavements built with both interlocking concrete blocks and with porous asphalt, as reported in the literature.

Storglaciären is a sub-Arctic polythermal glacier in northern Sweden. Twenty years' monitoring of thecold surface layer found that it has lost one third of its total volume of cold ice with an average thinningrate of 0.80 ± 0.24 m·a-1 for the period of 1989-2009. This thesis presents the continuous investigationof the thermal structure evolution of Storglaciären using thermistor string measurements and a coupledenergy balance-snowpack model. The thickness dynamics of the cold surface layer is derived from boththe thermistor string measurement (2018-2019) and the simulation results (2009-2018).    The subsurface temperature evolution and the associated cold-temperate transition surface (CTS)dynamics are analyzed at both the thermistor scale and glacier scale. Point study involves installing athermistor string and extrapolating the measured subsurface temperature to the pressure melting pointisotherm depth. The simulated CTS depth changes at the study site was also used for comparison. Glacierscale study aims to simulate the spatial and temporal variations of the thickness of the cold surface layer.Meteorological data was collected from multiple automatic weather stations and the solid precipitationwas estimated from the winter mass balance survey. The model was utilized in the study of the coldsurface layer dynamics for the first time.    Both the point scale and glacier scale study suggest an overall thickening trend of the cold surfacelayer. The thermistor derived CTS depth exhibits a thickening rate of ~0.9 m·a-1 compared to the depthderived from ground penetrating radar survey in 2009. The influence of mass balance, melt andaccumulation are also examined by spatial correlation with CTS depth. / Storglaciären är en subarktisk polytermal glaciär i norra Sverige som har ett kallt ytskikt iablationsområdet. Tidigare studier av mäktigheten hos det kalla ytskiktet visar att Storglaciären harförlorat en tredjedel av sin totala volym av kall is med en genomsnittlig uttunningshastighet på 0,80 ±0,24 m · a-1 för perioden 1989-2009. Denna uppsats presenterar den fortsatta utvecklingen av det kallaytskiktet på Storglaciären under perioden 2009 till 2019 med hjälp av istemperaturmätningar och enytenergi balansmodell koppla till en och en termodynamisk modell för snö och is. Istemperaturensutveckling och djupet till övergången mellan kall och tempererad is (CTS) analyseras både på lokalskalavid en punkt och över hela glaciären. Punktstudien utnyttjar temperaturmätningar vid en termistorslingaför att uppskatta temperaturfördelningen i isen och djupet för övergången mellan kall och tempereradis. Resultaten används också för jämförelse med simulerade resultat. Den rumsliga studien använder enkopplad energibalans och en termodynamisk modell för snö och is för att simulera rumsliga ochtidsmässiga variationer av tjockleken på det kalla ytskiktet. Som ingångsdata till modellen användesmeteorologiska data från flera automatiska väder stationer och den nederbörden i fast form uppskattadesfrån massbalans mätningar som görs på glaciären. Det är fösta gången den här typen av modell användsför att studera det kalla ytskiktets dynamik.    Både på lokalskala och glaciärskala tyder på en övergripande förtjockningstrend av det kallaytskiktet. Uppskattningen av CTS djupet vid temperaturmätningar uppvisar en ökningshastighet av ~0,9 m · a-1 av det kalla skiktets tjocklek jämfört med markradar undersökningar i 2009. Påverkan ochrumslig korrelation mellan massbalans, smältning och ackumulation på CTS-djupet undersöks också.

Atmospheric convection is sensitive to the nature of the surface and its temperature. Both dry (without cloud) and moist (with cloud) convections depend on the surface temperature. Surface temperature is of critical importance in several practical applications like human comfort and crop cultivation. In the climate change scenario too, variations in the surface temperature take the center stage. Therefore, prediction of surface temperature is important. The evolution of the temperature is governed by the energy equation and the surface temperature by the surface energy balance. Important components of the surface energy balance are radiation (incoming solar radiation, reflected solar radiation, incoming and outgoing longwave radiation), sensible and latent heat fluxes and heat flux into the ground (called ground heat flux). A large number of individual and collective observations have been carried out in the past to understand the atmospheric boundary layer and the surface energy budgets. However a major share of the observations is from mid-latitudes. There have been few experiments carried out in India, for example, MONTBLEX, LASPEX, etc. One common drawback among these experiments is that the data time series is discontinuous and continuous measurements covering an entire season are lacking. Moreover these measurements were not comprehensive and hence did not allowed to calculate complete surface energy balance – in some cases radiation data is not available while in some humidity data. Therefore, continuous time series of sufficient duration and covering all variables needed to look at the seasonal energy balance based on measurements alone is missing in the Indian context. New programmes with the main objective of predicting convection are being planned in India. For example, PROWNAM (Prediction of Regional Weather with Observational Meso-Network and Atmospheric Modeling) is aimed at predicting the short term weather at SHAR and STORM (Severe Thunderstorms – Observations and Regional Modeling) aims to predict the occurrence of severe thunderstorms in the northeastern India. In both these programmes, measurement of all components of surface energy balance is one of the main objectives. However, the minimum configuration and data accuracy requirements for the flux towers, sensitivity of computed fluxes on data accuracy have not been carefully evaluated. This thesis is aimed at filling this gap. As a part of my work, a 10 m high micrometeorological tower was installed in an open area within the Indian Institute of Science (IISc) Air Field. Temperature, relative humidity and wind speed and direction instruments were mounted at two levels, 2 m and 8 m. All components of radiation were measured. Data, sampled every 5 s and averaged for 2 minutes were continuously stored, starting May 2006 onwards. Soil temperature was measured at 4 depths, 5 cm, 10 cm, 15 cm and 20 cm. In addition, a sonic anemometer capable of measuring 3 components of velocity and air temperature was installed at 2 m height, and data was collected for more than a month to enable the calculation of momentum and buoyancy fluxes using the Eddy correlation method (ECM). The present work evaluated the sensitivity of the fluxes for small calibration errors and quantified the minimum data accuracies and configuration needed for flux measurement with the Profile method (PM). After applying corrections, the comparison of fluxes from PM and ECM are in good agreement. The complete long-term surface energy balances is calculated in terms of source and sink. One aspect that emerges from the observation is that the seasonal variation in the sink term is relatively small (150-170 Wm-2) whereas the source term shows much larger variation from 180-250 Wm-2. A method has been implemented by which the ground surface temperature can be estimated by using the subsurface temperature timeseries by the method of Fourier decomposition and using the Fourier heat conduction equation. In addition we can compute the thermal diffusivity of the soil by using the amplitude and phase information of the sub-surface soil time series. The estimated temperatures from this method and one that estimated from radiation method are in good agreement with the maximum difference being less than 0º C.

Als "surface-layer" (S-Layer, SL) bezeichnet man die regelmäßig strukturierten Hüllproteinlagen auf der Oberfläche von etwa 80 % aller bisher bekannten Bakterienspezies. Sie entstehen durch Selbstassemblierung von identischen Proteinuntereinheiten, die wiederum zumeist durch nichtkovalente Wechselwirkungen mit der darunterliegenden Zellwandkomponente verknüpft sind. Trotz ihrer Diversität auf der Ebene der Primärstruktur weisen S-Layer verschiedener Bakterienarten einheitliche physikochemische Merkmale auf. Dazu zählt u.a. die Wiedereinnahme einer hochgradig strukturierten, porösen Proteinschicht nach reversibler Denaturierung. Infolge der Reassemblierung entstehen sowohl in Lösung als auch an Phasengrenzen Proteinassemblate, deren Porenanordnungen die gleiche regelmäßige Symmetrie aufweisen, wie die nativen Hüllproteine auf der Bakterienzelle. Das in seiner Domänenstruktur aufgeklärte Hüllprotein SbsC des mesophilen Bakterienstammes Geobacillus (G.) stearothermophilus ATCC 12980 zeichnet sich durch eine ausgezeichnete Synthetisierbarkeit in E. coli aus. C-terminale Fusionen, die im Falle des verstärkt grün fluoreszierenden Proteins (EGFP) bis zu 240 Aminosäuren umfassen, führten nicht zu einem Verlust der Selbstassemblierung. Darüber hinaus zeigen in vitro gebildete SbsC-Assemblate eine außergewöhnliche Stabilität gegenüber hohen Ethanolkonzentrationen. Die durch gerichtete Mutagenese erzeugten SbsC-Fusionsproteine SbsC(aa 31-1099)-HspA und SbsC(aa 31-1099)-12His besitzen in assemblierter Form im Vergleich mit dem unmodifizierten Protein eine bis zu zweimal höhere Bindungsaffinität gegenüber Platinionen. In denaturierter Form waren beide Fusionsproteine in der Lage, Nickelionen zu komplexieren. In der vorliegenden Arbeit wurde erstmals ein SL-Protein in einem eukaryontischen Mikroorganismus produziert. Das in der Hefe S. cerevisiae gebildete Fusionsprotein SbsC(aa 31-1099)-EGFP assembliert dabei im Cytosol der Wirtszellen zu röhrenförmigen Assemblaten mit regelmäßiger Symmetrie. Das bisher unbekannte SL-Protein des Stammes G. stearothermophilus DSM 13240 wurde erfolgreich heterolog in E. coli exprimiert. Die Vorläuferform besitzt im Vergleich zum maturen Protein ein 31 aa umfassendes Sekretionssignal am extremen N-Terminus. Sowohl das authentische Protein als auch das heterolog in E. coli exprimierte Vorläuferprotein zeigen eine dem SbsC-Protein vergleichbare Reassemblierungscharakteristik. Im Gegensatz dazu führte die Verkürzung der N-terminalen 30 Aminosäuren des als S13240 bezeichneten Hüllproteins im heterologen System zu einem irreversiblen Verlust der Fähigkeit zur Selbstassemblierung.

In the present dissertation the formation of microstructure, the kinetics of densification and the formation of surface layers developing during liquid phase sintering of silicon carbide are studied. The focus is on the additive systems Al2O3 plus Y2O3 and AlN plus Y2O3. Phase and especially liquid phase formation in both of the systems SiC, Al2O3 , Y2O3 and AlN, Al2O3 , Y2O3 are investigated in detail examining 12 espectively 17 different compositions per system. Melting temperatures have been determined by TG/DTA, in both systems for the first time. Phase composition of samples was analysed by the combination of XRD, SEM and EDX. In the system SiC, Al2O3 , Y2O3 the formation of the phases expected from the quasibinary Al2O3 , Y2O3 could be observed thus silicon carbide has to be in equilibrium with the oxide additives. The low solubility of SiC in the oxide melt, which was suggested by Hoffmann and Nader, could be confirmed. In the system AlN, Al2O3 , Y2O3 the formation of phases as stated by Medraj was confirmed, except for the dimension of the stability region of the γ- spinel and YAG which is wider in the present work. For the first time diffusion coefficients of the species Y3+ and Al3+ in the oxide melt formed by Al2O3 and Y2O3 at temperatures above 1825 ◦ C were determined. The values are in the order of 2 · 10−6 cm2 /s which results in a diffusion length of 14.1 μm for a diffusion time of one second. This allows the fast equilibration of Y and Al deficiencies. Kinetics of densification was modeled by kinetic field, master curve and thermokinetic method, based on detailed experimental investigation of the shrinkage during liquid phase sintering of SiC. It could be proved that the first 30 − 40 % of densification are controlled by solid phase reactions which accelerate particle rearrangement without presence of a liquid phase. During the remaining 60 − 70 % of densification a liquid is present, resulting in the predominance of mechanisms of liquid phase sintering. The models deliver activation energies in the range from 608 KJ/mol to 1668 kJ/mol and allow, within the scope of validity of each method the prediction of densification during liquid phase sintering of silicon carbide. When sintering silicon carbide with Al2O3 plus Y2O3 the formation of several surface layers, depending on atmosphere, maximum temperature, dwelling time and amount and composition of additives was observed. In nitrogen atmosphere with low partial pressures a surface layer consisting of AlN is forming whilst at high partial pressures SiAlON- polytypes occur. After sintering in Argon or Ar-CO- atmosphere three main types of surface layers are present. One consists of alumina, one contains only YAG and one shows highly porous, additive depleted regions. An explanation for the formation of the several surface layers could be given by the combination of the determined diffusion coefficients with the results achieved in the thermodynamics part. The results achieved in this work can be a contribution to the knowledge based design of the production process of liquid phase sintering of silicon carbide.

Ce travail porte sur la recherche de différentes compositions de couches minces pouraccumulateurs Li-ion.Une première partie a été dédiée au dépôts de cathode sous forme de couche mince d’unmatériau connu, LiCoO2, et d’un matériau alternatif, Li(NiMnCo)O2 en utilisant le dépôtphysique en phase vapeur (PVD) et le dépôt chimique en phase vapeur (CVD),respectivement. Les résultats (LiCoO2) ont montrés comment, après cyclage, il y a diminutionde la capacité à cycler à régime rapide et augmentation de la résistance à l’interface. Ladiffraction des rayons X a montré la présence de différentes orientations, peu cristallisées,appartenant à la phase LiCoO2 HT selon confirmation par la littérature. Les couches mincesde Li(NixMnyCo1-x-y)O2 ont été préparées par dépôt chimique en phase vapeur assisté paraérosol. La diffraction des rayons X et l’analyse Rietveld utilisant le modèle March-Dollase aété mise en oeuvre pour la détermination de la texture et des caractéristiques microstructurales.La morphologie des films a été caractérisée par microscopie électronique à balayage. L’étudea montré que la concentration de la solution de précurseur et la pression totale ont un effetmajeur sur la morphologie des films et leur texture.Une seconde partie s’est focalisée sur l’interface cathode-électrolyte pour trois cas d’étude : 1)couche mince de matériau de cathode LiCoO2, 2) couche mince de LiCoO2 recouvert de ZrO2et 3) couche mince de LiCoO2 recouvert de LIPON. L’interface cathode-électrolyte de cestrois cas d’étude a été étudiée avant et après cyclage galvanostatique afin de déterminer lescaractéristiques de la couche de surface et les changements provenant à l’interface lors dufonctionnement de l’accumulateur. L’interface des couches minces de LiCoO2 a été étudiéeplus en détail après trempage dans un électrolyte liquide afin de comprendre l’effet desprocédures de stockages courts dans les accumulateurs.De plus, les couches minces de LiPON ont été étudiées sur la base de changementsstructuraux se produisant avec la nitruration et sa corrélation à un possible mécanisme ayantlieu durant la conduction ionique. / The present work was based on the investigation of different thin film components of Li ionbatteries. A first part was dedicated to the deposition of cathodes in thin film form of aknown material, LiCoO2, and an alternative one, Li(NiMnCo)O2 employing physical vapordeposition (PVD) and chemical vapor deposition (CVD), respectively. Results on thedeposition of LiCoO2 showed how after cycling there is a reduction of rate capability andincrease in interface resistance. The X-ray diffraction pattern showed the presence of severalorientations related to the known HT phases found in literature for LiCoO2 with lowcrystallinity. On the other hand Li(NixMnyCoz)O2 thin films prepared via aerosol assistedCVD were analyzed with X-ray diffraction and Rietveld refinement using the March-Dollasemodel for the determination of the texturing and microstructural characteristics. Additionallythe morphology of the films was characterized using scanning electron microscopy. Theinvestigation showed that concentration of precursor solution and process pressures have asignificant effect on the film morphology and texturing. A second part was focused on the cathode-electrolyte interface for three case studies: 1) asdeposited LiCoO2 cathode thin film, 2) ZrO2 coated LiCoO2 thin film and 3) LiPON coatedLiCoO2 thin film. The interface cathode-electrolyte of these three cases were studied beforeand after galvanostatic cycling to determine surface layer characteristics and changes arisingon the interface after battery operation. The interface of a bare LiCoO2 layer was furtherstudied after soaking in liquid electrolyte to elucidate the effect of short storage procedures inbatteries.Surface analysis done on LiCoO2 thin films showed changes occurring at the interface layersafter the electrode was in short contact with the electrolyte solution and after galvanostaticcycling. Washing and soaking the electrode material in electrolyte and solvent showed thatsurface reactions start from the first contact. A main component of the electrolyte solution,LiPF6, has critical effect since it can decompose and form HF which reacts with carbonatesand forms LiF on the surface. Given the large amount of LiF, a high reactivity of LiCoO2 withthe decomposed species was observed, as the main components of the film were related to thedecomposed LiPF6 salt.The surface chemistry of the layer formed on LiCoO2 after cycling was mainly based ondecomposed species from the electrolyte salt arising from carbonated and fluorinated species.Artificial surface layers were deposited on LiCoO2 by means of rf sputtering. The thin layersof ZrO2 and LiPON used as coatings had minor effects on the original film morphology andcrystalline structure. An XPS analysis of the interface showed how the nature of each layerafter galvanostatic cycling was different for each case. The resulting artificial surface layerformed from ZrO2 coating showed mainly inorganic species, while the LiPON coatedcathode showed an organic nature. The final surface layers after electrochemical cycling ofthe ZrO2 coated film resembled that of the uncoated LiCoO2. Additionally, LiPON thin films were studied on the basis of structural changes occurringwith nitrogenation and its correlation to a possible mechanism during ion conduction.Composition of phosphate glasses with rf sputtering was proven to be greatly influenced bythe gas ratio employed. The largest variations were observed for lower amounts of N2 in thegas mixture. The IR spectra results showed important differences in the short range order forfilms with a similar amount of lithium. The lithium phosphorus oxynitride films depositedhere presented glassy structures with mainly ortho and pyro-phosphate units with smallamounts of short metaphosphate chains. Nitrogen insertion favors stability of lithium bygiving an environment with lower potential energy, as was evidenced by the far-IR results.

Submitted by Jos? Henrique Henrique (jose.neves@ufvjm.edu.br) on 2016-12-15T19:19:18Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) luana_cristielle_araujo.pdf: 2395383 bytes, checksum: 9bb2ed4d6dcfdf6793777225baf50c2c (MD5) / Approved for entry into archive by Rodrigo Martins Cruz (rodrigo.cruz@ufvjm.edu.br) on 2016-12-19T16:41:00Z (GMT) No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) luana_cristielle_araujo.pdf: 2395383 bytes, checksum: 9bb2ed4d6dcfdf6793777225baf50c2c (MD5) / Made available in DSpace on 2016-12-19T16:41:00Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) luana_cristielle_araujo.pdf: 2395383 bytes, checksum: 9bb2ed4d6dcfdf6793777225baf50c2c (MD5) Previous issue date: 2015 / O objetivo deste trabalho foi gerar conhecimento sobre a aplica??o de diferentes t?cnicas na restaura??o de ambientes degradados pela minera??o de ferro. A disserta??o foi estruturada em tr?s cap?tulos, sendo o primeiro uma revis?o de literatura, com intuito de retratar os temas abordados na disserta??o. No segundo, avaliou-se o espa?amento de plantio para Vellozia ramosissima e Pseudobombax campestre no modelo de plantio em Leque, visando gerar conhecimento sobre o manejo dessas esp?cies resgatadas na reintrodu??o a ambientes degradados. Para tal depositou-se sobre uma pilha de est?ril de canga ferruginosa uma camada de topsoil associado ? canga ferruginosa, onde foi instalado o experimento em delineamento sistem?tico tipo ?Leque?, conforme o modelo (IA) proposto por Nelder (1962), em que se avaliou oito espa?amentos de plantio, variando de 2 m?/planta a 9,3 m?/planta. As vari?veis analisadas foram o incremento em altura e di?metro de P. campestre, al?m da sobreviv?ncia de V. ramosissima e P. campestre aos quatro, oito e doze meses ap?s o replantio. Para avaliar os melhores tratamentos foram realizadas an?lises de vari?ncia (ANOVA) a 5% de signific?ncia. Para a sobreviv?ncia realizou-se o teste n?o-param?trico de Kruskal-Wallis a 5% de signific?ncia. As duas esp?cies estudadas apresentaram nos per?odos avaliados sobreviv?ncia acima de 80%. O incremento em altura e di?metro de P. campestre foi crescente ao longo do per?odo avaliado, apresentando uma m?dia geral 34,3 cm e 16,6 mm, respectivamente, durante os doze meses ap?s o replantio. Ressalta-se que os espa?amentos de plantio testados para as esp?cies deste estudo n?o apresentaram diferen?as significativas para todas as vari?veis analisadas. O terceiro cap?tulo teve como objetivo avaliar o potencial do uso da camada superficial de solo ?topsoil? associado ? canga ferruginosa, como alternativa na recomposi??o da cobertura vegetal de uma pilha de est?ril de canga ferruginosa. A comunidade regenerante foi amostrada aos 10 e 18 meses, ap?s a deposi??o do topsoil. Assim, determinou-se a densidade de plantas, composi??o e diversidade flor?stica, al?m de avaliar a din?mica de popula??es e cobertura do solo. A cobertura vegetal proveniente do topsoil ao final do per?odo avaliado apresentou um total de 19.485 indiv?duos pertencentes a 26 fam?lias com 82 esp?cies e seis morfoesp?cies. As fam?lias com maior n?mero de esp?cies foram Asteraceae (16), seguidas de Fabaceae (11) e Poaceae (8). A cobertura m?dia do solo na ?rea experimental foi de 58%, ap?s 18 meses. A utiliza??o do topsoil mostrou-se como uma t?cnica promissora e de extrema import?ncia na indu??o da restaura??o da pilha de est?ril de canga ferruginosa, uma vez que proporcionou a regenera??o natural, recomposi??o da vegeta??o com esp?cies aut?ctones, crescimento satisfat?rio dos indiv?duos e r?pida cobertura do solo ao longo do per?odo avaliado. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Ci?ncia Florestal, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2015. / This work aimed at generating knowledge on the application of different techniques in the restoration of degraded environments due the iron mining. The master's thesis was structured into three chapters, where the first is a literature review which portrays the issues addressed in the thesis. In the second chapter we evaluated the planting spacing for Vellozia ramosissima and Pseudobombax campestre in fan-shaped planting model, aiming at generating knowledge on the management of the two species when reintroduced in degraded environments. For this purpose we deposited on a pile of sterile ferruginous yoke one topsoil layer associated with the ferruginous yoke, where we conducted the experiment in a fan-shaped systematic design, according to the model (IA) proposed by Nelder (1962), in which were evaluated eight planting spacings ranging from 2 m?/plant to 9.3 m?/plant. We analyzed as variables the increase in height and diameter of P. campestre and the survival of V. ramosissima and P. campestre in the fourth, eighth, and twelveth months after replanting. In order to evaluate the best treatments we performed variance analysis (ANOVA) at 5% significance level. For survival we used the nonparametric Kruskal-Wallis test at 5% significance level. Both the studied species showed survival above 80% in the evaluated periods. The increment in height and diameter of P. campestre was increasing over the studied period, presenting an overall average of 34.3 cm and 16.6 mm, respectively, during the twelve months after replanting. We point out that the plant spacings for the species tested in this study presented no significant differences for all variables. The third chapter aimed at evaluating the potential use of the surface layer of "topsoil" associated with ferruginous yoke, as an alternative in the vegetation cover restoration of a waste pile of ferruginous yoke. The regenerating community was sampled in the 10th and 18th months after the deposit of topsoil. Therefore, we determined the plant density, the composition and the floristic diversity, and we also evaluated the dynamics of populations and soil coverage. The vegetation provided by the topsoil by the end of the studied period showed a total of 19,485 individuals which belong to 26 families with 82 species and six morphospecies. The families with the highest number of species were Asteraceae (16), followed by Fabaceae (11), and Poaceae (8). The average coverage of the soil in the experimental area was 58% after 18 months. The use of topsoil was shown as a promising and extremely important technique in inducing the restoration of the waste pile of ferruginous yoke, once it provided natural regeneration, vegetation restoration with native species, satisfactory growth of individuals, and quick soil coverage over the studied period.

O emprego de pavimentos permeáveis tem se tornado cada vez mais necessário como medida compensatória para amortecer as vazões de pico e atenuar os impactos gerados pelas chuvas torrenciais em áreas altamente urbanizadas. Dentre os materiais convencionalmente adotados como revestimento permeável no contexto nacional destacam-se os blocos de concreto intertravados (BCI) e o asfalto poroso. No entanto, internacionalmente, existem materiais alternativos que podem apresentar permeabilidade igual ou até mesmo superior. Sob esse prisma, convém destacar o uso dos blocos de concreto articulados (BCA), recentemente adotados nos Estados Unidos e na Coréia do Sul, cuja capacidade de infiltração vem mostrando-se bastante promissora. Diferentemente dos blocos intertravados, os BCA foram projetados para trabalhar em conjunto, já que são interconectados por meio do encaixe das articulações unidirecionais de cada peça, sobrepostas umas às outras, dispensando assim o uso de material de rejunte, o que por sua vez aumenta a permeabilidade do revestimento. Contudo, embora o desempenho hidráulico aparente ser eficaz, questiona-se se o pavimento de blocos de concreto articulados (PBCA) comporta-se de forma igualmente satisfatória em termos estruturais. Nesse sentido, visando avaliar o desempenho estrutural e hidráulico de um pavimento permeável de BCA, foi construída uma pista experimental (20 x 5 m) no Campus da USP, adotando-se dois tipos de base, uma de agregado reciclado (RCD) e outra de agregado natural (brita 1). Na análise estrutural utilizaram-se como parâmetros de avaliação as deflexões máximas obtidas via FWD (Falling Weight Deflectometer), a eficiência de transferência de carga (LTE - Load Transfer Efficiency) e por fim, os módulos de resiliência retroanalisados para cada camada. Ademais, a pesquisa ainda avaliou a influência da presença de fissuras ou trincas nos blocos no desempenho estrutural do pavimento, já que acabaram tornando-se recorrentes em ambas as seções avaliadas. Já na avaliação hidráulica, monitorou-se a taxa de infiltração in situ ao longo de quase vinte meses. Complementarmente, foram realizadas ainda avaliações laboratoriais dos materiais empregados e funcionais do pavimento. A análise estrutural indicou que o sentido articulado do BCA obteve respostas estruturais nitidamente melhores que o sentido não articulado em termos de módulo de resiliência, deflexões máximas e LTE, evidenciando que de fato as articulações conferem intertravamento ao pavimento, próximo ao propiciado pela areia de rejunte no BCI. A base de RCD por apresentar uma distribuição granulométrica mais bem distribuída do que a brita 1, também obteve melhores resultados. Já a presença de trincas ou fissuras nos blocos não acarretou comprometimento no desempenho estrutural da pista experimental, devido ao baixo grau de severidade da maioria das patologias encontradas, como atestou o levantamento funcional, cuja classificação indicou um pavimento em boas condições de serventia. No que diz respeito ao desempenho hidráulico, o pavimento apresentou um desempenho adequado em termos de capacidade de infiltração. Apesar da perda progressiva estimada em 20% ao ano, as taxas de infiltração in situ mantiveram-se acima de 10-3 m/s em todos os ensaios realizados, sendo, portanto, superior à maioria dos revestimentos permeáveis tradicionalmente utilizados como os blocos intertravados e a camada porosa de atrito, conforme descritos pela literatura. / Pervious pavements have become increasingly fundamental as a compensatory measure to attenuate peak flows and to mitigate the impacts generated by torrential storm water in highly urbanized areas. Among the usual materials applied in permeable surface layers, it is possible to highlight the interlocking concrete blocks (ICB) and the porous asphalt. However, internationally, there are alternative materials that are able to present a higher permeability. In this sense, the use of articulated concrete blocks (ACB) needs to be stressed. Recently adopted in United States of America and South Korea, ACB has presented promising infiltration rates. Unlike the ICB, the ACB was designed to work as an integrated framework due to the presence of articulated joints in one of the block directions, which allows discarding the jointing sand and as result, increases water infiltration. Nevertheless, although the pavement hydraulic performance seems to be successful, there are some doubts about the structural behavior. Thereby, aiming at evaluating the hydraulic and structural performance of an unidirectionally articulated concrete block pavement, a pavement experimental section (20 x 5 meters) was constructed at the University of São Paulo Campus. Two types of different bases were applied, namely recycled concrete aggregate (RCA) and natural aggregate. The structural assessment took into account the maximum deflection measurements, the load transfer efficiency (LTE) and the backcalculated elastic moduli of each layer. In addition, this work also evaluated the structural influence caused by the presence of damaged pavers, since it became a recurring problem. Regarding the hydraulic evaluation, the surface infiltration rate was monitored over twenty months after the pavement construction. Furthermore, functional and laboratorial analyses were carried out in order to check the structure serviceability level. The structural results indicated clearly that the articulated block side had better performance than the non-articulated block side in terms of elastic moduli, maximum deflections measurements and LTE, confirming the interlocking efficiency generated by the block shape, comparable to that one provided by the jointing sand in ICB. As the recycled aggregate was characterized by a more well graded particle size distribution than the natural aggregate, the RCA base also presented better structural responses. The presence of damaged blocks did not compromise the pavement structural performance, since the degree of severity was low, as verified by the functional evaluation, which showed a pavement in good conditions. Finally, concerning the hydraulic results, the pavement presented a high infiltration capacity. Even though an infiltration loss of about 20% per year has been detected, the infiltration rate remained greater than 10-3 m/s for all tests performed, being considerably higher than those found in pavements built with both interlocking concrete blocks and with porous asphalt, as reported in the literature.

Made available in DSpace on 2014-08-20T14:25:47Z (GMT). No. of bitstreams: 1 dissertacao_theo_hackbart.pdf: 2892534 bytes, checksum: 4bd14c0e449a0233a7d5e1098733bf8f (MD5) Previous issue date: 2008-11-28 / This work describes the construction of an unmanned aerial vehicle (UAV) with electrical propulsion and instrumentation in order to obtain the vertical and horizontal profiles by measuring temperature, pressure, and GPS location, in surface atmosphere layer between two heterogeneous surfaces near terrain. Using embedded electronic, one developed and built a small platform with approximately 50 grams in order to collect and acquire meteorological data. The electronic circuit is based on a PIC microcontroller with pressure and temperature sensors, and GPS. After capturing aerosondes data, the first analysis was done. By using these data, surface boundary layer structure compatible with general concepts in the literature were identified. It was also identified some details of closed structures to the frontier which separates the heterogeneous region of landcover. According to several researches aiming at sdudying different alternatives to obtaining the data, one demonstrated through this experimental that small UAVs can be very useful for agrometheorology and metheorology researches because they provide the atmospheric sounding to be performed in places where the access is difficult. Furthermore, they present a low cost. / Este trabalho descreve a construção de um veículo aéreo não tripulado (VANT) com propulsão elétrica, instrumentalizado, para obter perfis verticais e horizontais de medidas de temperatura, pressão e localização por GPS, na camada superficial da atmosfera entre duas superfícies heterogêneas próximas ao solo. Utilizando eletrônica embarcada, desenvolveu-se e implementou-se uma pequena plataforma com aproximadamente 50 gramas para coleta e aquisição de dados meteorológicos. O circuito eletrônico é baseado no microcontrolador PIC com sensores de temperatura, pressão e GPS. Após a captação de dados na aerossondagem, foi realizada uma primeira análise. Usando esses dados, identificaram-se as estruturas da camada-limite superficial compatíveis com os conceitos gerais descritos na literatura, assim como detalhes da estrutura próximos às fronteiras de separação de regiões heterogêneas de coberturas de solo. Tendo em vista as inúmeras pesquisas que visam a alternativas diferenciadas para obtenção de tais dados, mostrou-se, através deste experimento, que pequenas aeronaves não-tripuladas podem ser de grande valia para pesquisas em agrometeorologia e meteorologia, pois se destacam por possibilitar a realização de sondagens atmosféricas em lugares de difícil acesso, tendo um baixo custo.

Climate change in the Arctic and sub-Arctic has induced substantial changes in the inland cryosphere. The warming climate is causing a reduction in glacier size and extent and the average net mass balance for Arctic glaciers have been negative over the past 40 years. Relatively few studies have been conducted concerning the development of the thermal distribution in glaciers during extensive volume changes. There is a possible diversity in how the thermal structure might change with a changing climate. Storglaciären is losing the cold surface layer in the ablation area and progressively becomes more temperate, while Kårsaglaciären is losing the zone of temperate ice in the ablation area and consequently becoming colder. The overall objective of this study has been to improve the understanding of the thermal response of polythermal glaciers to climate change. The results from Pårteglaciären, northern Sweden, indicate a decrease in volume by 18% in the last 15 years with an expected decrease of 35% of its present size during the coming century. As a consequence of the prevailing climate and volume decrease Pårteglaciären is experiencing a thinning of the cold surface layer at an average rate of 1.13 m a-1. The volumetric and cold surface layer changes are in the same magnitude, which may indicate that the CTS adapts relatively rapidly to the present changes. Assuming a climatic effect similar to what has been observed on Storglaciären, it can be concluded that the thinning has influenced the thermal regime. But in contrast to Kårsaglaciären, the thermal distribution on Pårteglaciären has become more temperate as a result of the substantial mass loss. / Klimatförändringar i Arktis och subarktis har orsakat stora förändringar i kryosfären. Ett varmare klimat orsakar en minskning av glaciärers storlek och omfattning och nettomassbalansen för Arktiska glaciärer har varit negativ under de senaste 40 åren. Relativt få studier har genomförts angående utvecklingen av den termiska fördelningen i glaciärer under omfattande volymförändringar. Det finns en möjlig diversitet i hur den termiska strukturen kan ändras med ett förändrat klimat. Storglaciären förlorar det kalla ytskiktet i ablationsområdet och blir successivt mer tempererad, medan Kårsaglaciären förlorar zonen med tempererad is i ablationsområdet och blir därmed kallare. Syftet med den här studien har varit att öka förståelsen för den termiska reaktionen hos polytermala glaciärer till ett förändrat klimat. Resultaten från Pårteglaciären i norra Sverige visar en volymreducering med 18% under de senaste 15 åren med en förväntad minskning på 35% av den nuvarande storleken under det kommande århundradet. Som en följd av det rådande klimatet och den reducerade volymen genomgår det kalla ytskiktet på Pårteglaciären en förtunning med en genomsnittlig hastighet av 1.13 m a-1. Volymförändringarna och förändringarna i kalla ytskiktet är i samma storleksordning, vilket tyder på att CTS anpassas relativt snabbt till de nuvarande förändringarna. Förutsatt en klimatisk effekt liknande den som observerats på Storglaciären, kan slutsatsen dras att förtunningen har påverkat den termiska regimen. Men i motsats till Kårsaglaciären har den termiska fördelningen på Pårteglaciären blivit mer tempererad som ett resultat av den omfattande massförlusten.