http://hdl.handle.net/11422/15 Sun, 26 Jul 2026 00:23:41 GMT 2026-07-26T00:23:41Z http://hdl.handle.net/11422/29774 Title: Os esfagessaurídeos da Bacia Bauru Author(s)/Inventor(s): Iori, Fabiano Vidoi Advisor: Carvalho, Ismar de Souza Abstract: The Notosuchia was a characteristic and peculiar group in the geological history of the Gondwanic Cretaceous. These crocodylomorphs possessed a very specialized dentition and occurred in several ecological niches. In this context the sphagesaurids present a complex masticatory mechanism adapted for herbivory / omnivory. Four genera have been described for this family: Sphagesaurus, Armadillosuchus, Caipirasuchus and Caryonosuchus, all from the Bauru Basin. This basin is located in south-central South American Platform and consists of Late Cretaceous continental deposits. The descriptions of some sphagesaurids were based on the fragmentary fossils and/or uncompleted preparation; then some morphological characters were incorrectly described. The anatomical reanalysis and the discovery of new specimens allowed the taxonomic revision and annotation of a diagnosis for the family based on the following dental pattern: presence of six sphagesauriform teeth in each maxilla and six on each dentary, each upper tooth with an antagonic tooth in the jaw; premaxilla with a caniniform tooth and another conical tooth posteriorly. Adamantinasuchus possess distinct dentition and chewing mechanism; theses aspects and a phylogenetic analysis exclude it from the family Sphagesauridae. The analysis of new aspects related to chewing on Caipirasuchus corroborated previous proposals for the family, as the proal and unilateral movements of the jaw during the bite. Moreover, it was pointed the function of the diastemata and square-articular joint in the masticatory process. The study of the post-cranium of the Caipirasuchus specimens allowed to estimate that these animals had thin bodies and 1.20 m in length. The analysis of anatomical structures of Sphagesaurus, Caryonosuchus, Armadillosuchus allowed to propose an ecological niche for the Sphagesauridae Publisher: Universidade Federal do Rio de Janeiro Type: Tese Thu, 05 Dec 2013 00:00:00 GMT http://hdl.handle.net/11422/29774 2013-12-05T00:00:00Z http://hdl.handle.net/11422/29754 Title: Mecanismos evolutivos de bacias de drenagem em diferentes escalas de tempo: Rio Japuíba (Angra dos Reis, RJ) Author(s)/Inventor(s): Freitas, Fabiana Peres de Advisor: Silva, Telma Mendes da Abstract: Understanding the evolution of a drainage basin requires expressing qualitatively and quantitatively the forms, processes and their interrelationships. The analysis of the arrangement of river systems elucidates geomorphological issues, since watercourses are active agents in landscape modeling. The research seeks to investigate the evolutionary mechanisms through the integration of different methodologies, considering the analysis of tectono-structural control, the quaternary sedimentary dynamics proposing an evolutionary model for the Japuíba river basin, in addition to the recognition of technogenic terrains. The detailed analysis of the basin, located in Angra dos Reis and formed by the Japuíba and Cabo Severino rivers, with a predominance of steep mountain ranges in contact with fluvial-marine plains, was carried out from the division into three sub-basins (Banqueta-Japuíba, Cabo Severino and Japuíba do Meio) and revealed distinct characteristics, shaped by geological and anthropogenic processes over time. The Banqueta-Japuíba sub-basin stands out for its high tectonic influence, evidenced by high values of the Tectonic Activity Index (IAT), with abrupt slopes that increase the risk of erosion and landslides. The colluvial rock morphodynamics, with confined and partially confined valleys, gives the sub-basin high susceptibility to changes. On the other hand, the anthropogenic changes that predominate are technogenic equiforms. The Banqueta-Japuíba sub-basin stands out for its high tectonic influence, evidenced by high values of the IAT. The relief has steep slopes that increase the risk of erosion and landslides. The colluvial rock morphodynamics, with confined and partially confined valleys, gives the sub-basin high susceptibility to changes. Anthropogenic changes in the terrain are rare, with a predominance of technogenic equiforms, and quaternary sedimentation rates are lower, indicating the predominance of erosive processes and material transport. The Cabo Severino sub-basin also presents tectonic-structural control, with very high values of IAT. The relief exhibits a mature drainage system due to intense erosion. The morphodynamics are similar to the Stool, but with fewer drainage elbows and a non-confined section, making it a little more susceptible to changes. Anthropogenic changes include equiforms, scars, depressions, elevations, and technogenic superpositions. Quaternary sedimentation is small, given environments of high erosive energy. The Japuíba do Meio sub-basin, in turn, has a high tectonic influence, but less intense than the previous ones. The relief exhibits a lower risk of erosion and landslides, with areas of sediment accumulation. The anthropized alluvial morphodynamics, with an unconfined fluvial style, show a strong human influence on the modification of the channel and fluvial processes. The changes in the terrain are numerous, with the presence of equiforms, scars, depressions, elevations and technogenic superpositions, reflecting the greater population occupation. The sub-basin has the largest area of Quaternary sedimentation, with recent and continuous sedimentary activity, in addition to being the stretch of the basin that suffers the most from siltation due to human action. The evolutionary analysis of the basin in different time scales, long and short, allowed us to understand the fluvial dynamics and anthropogenic interferences. On the long time scale, tectonic-structural compartmentalization and Quaternary sedimentation showed a strong influence on the conformation of the basin, as well as on the distribution and retention of Quaternary age sediments. On the short time scale, the current erosive processes and the classification of fluvial styles (confined, partially confined and unconfined) indicate different degrees of morphodynamics of fluvial channels and the growing influence of human action, especially in the Japuíba do Meio sub-basin. The investigation of geometry and geomorphological processes demonstrated how the basin was driven by climatic events, tectonics, by the variation of vegetation cover and human activity. In fact, the increasing degradation of river systems has generated significant impacts on the rates of geomorphic processes in the landscape. This problem requires a more efficient environmental management, which involves understanding the characteristics and behaviors of the relief and river system. Publisher: Universidade Federal do Rio de Janeiro Type: Tese Mon, 07 Apr 2025 00:00:00 GMT http://hdl.handle.net/11422/29754 2025-04-07T00:00:00Z http://hdl.handle.net/11422/29715 Title: Dynamical Casimir effects with atoms and spinning nanoparticles Author(s)/Inventor(s): Matos, Guilherme Costa Advisor: Maia Neto, Paulo Américo Abstract: Motivated by recent experiments with levitated, ultra-fast rotating nanoparticles, this thesis presents new effects in the interaction of spinning particles with the quantum vacuum. The first part of the thesis studies the quantum electrodynamical analog of the Sagnac effect, in which the rotation of a neutral particle in the vicinity of an atom interferometer induces a phase on the propagating matter waves. The resulting phase is a geometric Berry phase proportional to the angular velocity of the particle. A rotation confined to a region of space leaving a trace of non-inertiality in an inertial frame suggests an analogy with the Aharonov-Bohm effect. Taking the particle’s plasmon resonances account, the analysis reveals that the phase magnitude is close to the limit of measurement for current state of the art atom interferometers. The force on an atom by a rotating particle is also calculated, and is shown to be analogous to the Coriolis force. The second part of the thesis deals with the photon emission by a rotating non-spherical neutral particle. Provided that the rotation axis is orthogonal to particle symmetry axis, the interaction of the particle with the field produces frequency sidebands of the scattered field, leading to the emission of dynamical Casimir photon pairs. The photon emission rate is obtained for metallic and dielectric spheroids and is enhanced when the rotation frequency is near a plasmonic or polaritonic resonance. In order to optimize the emission rate, the velocity of the particle’s tip is fixed and the dependence with the particle’s geometry is considered. Publisher: Universidade Federal do Rio de Janeiro Type: Tese Thu, 18 Dec 2025 00:00:00 GMT http://hdl.handle.net/11422/29715 2025-12-18T00:00:00Z http://hdl.handle.net/11422/29696 Title: Carbetos metálicos para a hidrogenólise do 5-Clorometilfurfural a 2,5-Dimetilfurano: um precursor do pxileno verde Author(s)/Inventor(s): Coutinho, Sofia Guerson Gonçalves Advisor: Ferraz, Camila Palombo Abstract: This work investigates the application of metal-based catalysts in the conversion of biomass-derived platform molecules into higher value-added compounds. The hydrogenolysis of 5-chloromethylfurfural (CMF) and 5-hydroxymethylfurfural (HMF) to produce 2,5-dimethylfuran (DMF) was studied. DMF is a promising compound both as a biofuel and as an intermediate to produce green p-xylene. CMF stands out as an alternative to HMF due to its easier separation and high yields from different lignocellulosic biomass sources. In this context, palladium supported on carbon (5% Pd/C) and transition metal carbides were evaluated as catalysts, particularly molybdenum carbide (Mo₂C) and tungsten carbide (W₂C), aiming at lower-cost catalytic alternatives compared to noble metals. The catalysts were synthesized and characterized using techniques such as X-ray diffraction (XRD), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM–EDS), temperature-programmed carburization (TPC), Raman spectroscopy, and CO chemisorption. Catalytic tests were carried out in a reactor under a hydrogen atmosphere, and the reaction products were analyzed by gas chromatography. The results indicate that 5% Pd/C exhibited high catalytic activity for hydrodeoxygenation (HDO) and hydrodechlorination (HDC) reactions, achieving 100% conversion and selectivity higher than 60% toward DMF from both HMF and CMF. Transition metal carbides showed relevant catalytic properties for the HDC reaction of CMF, with selectivity toward the formation of an important intermediate for DMF production. Publisher: Universidade Federal do Rio de Janeiro Type: Dissertação Thu, 01 Jan 2026 00:00:00 GMT http://hdl.handle.net/11422/29696 2026-01-01T00:00:00Z