Aluminum alloy castings are becoming commonplace for critical applications in the automotive and aerospace industries where materials failure is not an option. In order to meet such property demands, tight control over the cleanliness of the melt (mitigation of solid particle inclusions) and microstructure must be achieved. In order to control cleanliness, it must first be well defined and measured. Very few techniques exist in industry that can quantitatively measure inclusion levels in-situ. Laser-induced breakdown spectroscopy (LIBS) is presented as a promising technique to quantify solid particles, desired or undesired, in aluminum melts. By performing LIBS with subsequent statistical analysis on liquid aluminum with varying concentrations of Al2O3, AlB2, TiB2, and SiC particles, calibration curves relating particle concentration and elemental intensity were drawn. Through metallography and automated electron microscopy, it was found that inclusions less than 10 um in size could be detected with LIBS. Concentrations down to at least one part-per-million could be detected and accurately measured, allowing for LIBS to be use as a tool for complete, real-time melt cognition.

The prevailing use of chemical pesticides has generated several problems including insecticide resistance, outbreak of secondary pests, safety risks for humans and domestic animals, contamination of ground water and decrease in biodiversity among other environmental concerns (Webster, 1982). These problems and the nonsustainability of control programs based mainly on conventional insecticides have stimulated increased interest in the development and implementation of costeffective, environmentally safe alternatives to chemical pesticides for insect pest control. One of the most promising strategies to help minimize dependence on chemical pesticides has been the recent application of entomopathogenic nematodes (EPNs) as biocontrol agents. EPNs in the families Steinernematidae and Heterorhabdidae have been shown to have considerable potential as biological control agents. As a natural process, biological control has the potential to play an important role in the suppression of field crop pests in agriculture. EPNs as biocontrol agents have the following advantages: high virulence, safety to non target organisms, ability to search for hosts, high efficacy in favourable habitats, high reproductive potential, ease of mass production, ease of application (Ferron & Deguine, 1996). To isolate the EPNs in South African soil, 200 soil samples were randomly collected from 5 locations in the agricultural research council (ARC) Pretoria, Gauteng province in April 2006; and 5 locations in Brits, North West province in March, 2006. At the different collection sites, soil samples were obtained from soils associated with various types of vegetation. The nematodes were collected from sandy soil by the insect-baiting technique and maintained successfully in vivo for 12 months on Galleria mellonella (G. mellonella), 4 months on Tenebrio molitor (T.molitor); 2 months Pupae and in vitro (lipid agar) for 2 weeks in the laboratory. Out of a total of 200 soil samples that were baited, 2 were found to be positive for EPNs.EPNs. IV In addition to completing Koch’s postulates, the colour of cadavers infected by the putative EPNs were also used as a diagnostic characteristic for categorizing the nematode isolates. Characterization and identification of the EPN isolates were based on morphological characters, as well as on a molecular marker (18S rDNA). On the basis of the morphological and molecular data that was obtained both of the EPNs isolates were placed in the family Heterorhabdidae: Heterorhabditis bacteriophora (H. bacteriophora) and Heterorhabditis zealandica (H. zealandica). Also from the phylogenetic trees generated from the 18S rDNA sequence, the indigenous putative H. bacteriophora was shown to be closely related to H. bacteriophora (accession number EF690469) and indigenous putative H. zealandica to H. zealandica (accession number AY321481). The two EPNs were found associated with Gram negative rod-shaped bacteria. The bacterial symbionts of the two isolates were isolated and a region of the 16S rDNA gene was sequenced. National Center for Biotechnology Information (NCBI-BLAST) results of the 16S rDNA sequence obtained showed the endosybiotic bacteria to be Photorhabdus luminescens laumondii (P. laumondii) (H. bacteriophora) and Photorhabdus sp (H. zealandica). Results of the tree showed that isolates from H. bacteriophora appeared to be closely related to P. luminescens subsp laumondii strain TT01 Ay 278646. The isolates from H. zealandica appeared to be most closely related to Photorhabdus sp Accession number: Q 614 Ay 216500). Bioassays were used to determine the infectivity of the two EPNs. In this experiment different infective juvenile (IJs) concentrations (5, 10, 25, 50, 100,200 400 and 500) of the two EPNs were applied per G. mellonella; T. molitor larva and pupae. The bioassay was carried out in two parts. In the first part, mortality data was collected for H. bacteriophora and H. zealandica. The results showed that the degree of susceptibility of G. mellonella, T. molitor larvae and pupae to each nematode species was different. When 24 h post-exposure mortality data for larvae exposed to the IJs of H. bacteriophora and H. zealandica were analyzed, ANOVA showed no differences V in mortality between insects exposed to different H. bacteriophora IJ doses (Fig: 8.1 ABC). However, there were significant differences in mortality between insects exposed to different IJ doses of H. zealandica such as 5 and 500 IJs/insect (Fig: 8.2 ABC) Therefore, no differences were noted when mortality data was compared between IJ doses at both 72 h and 96 h following IJ application to the insects. The highest susceptibility was observed with G. mellonella followed by T. molitor pupae and then T. molitor larvae. According to Caroli et al., (1996), the total mortality of insect such as G. mellonella and other lepidopterans, was reached within 24-72 h of exposure to nematodes at concentrations such as those tested here. In this study similar results were observed with high concentration of nematodes (100, 200 and 500). In the second part of the dose response bioassay, the number of progeny IJs emerging from EPN-infected cadavers was determined for all two EPNs. The results indicate that IJ progeny production differed among the three insect hosts used, the IJ doses they were exposed to, as well as the EPN species (Figs 8.3 & 8.4). The highest number of emerged IJs of H. zealandica was produced by G. mellonella (mean ± SEM: 220500 ± 133933 IJs), followed by T. molitor larvae (mean ± SEM: 152133 ± 45466 IJs) and the lowest then T. molitor pupae (mean ± SEM: 103366 ± 56933 IJs).

Neste trabalho foram estudadas 10 corridas em duas usinas siderúrgicas semi-integradas, de aço baixa liga para uso em construção mecânica. Em cada uma das corridas foram retiradas 9 amostras, cada uma ao final de uma etapa do processo de produção: após a remoção de escória na panela, antes da desgaseificação a vácuo, após a desgaseificação a vácuo, após a adição de arame de Al, após a adição de arame de CaSi, após a adição de arame de S, após o fim da turbulência no distribuidor no lingotamento contínuo, 30 minutos após o fim da turbulência no distribuidor no lingotamento contínuo, e 60 minutos após o fim da turbulência no distribuidor no lingotamento contínuo. As amostras foram preparadas metalograficamente e analisadas ao microscópio eletrônico de varredura (MEV) com espectrometria de dispersão de energia (EDS), a fim de se identificar as inclusões presentes no aço em cada etapa do processo. Com isto pode-se fazer a caracterização das inclusões encontradas em cada etapa do processo e a sua classificação segundo a composição química e morfologia. Através da comparação da composição química das inclusões encontradas ao final do refino e no lingotamento contínuo foi possível verificar uma tendência de formação de inclusões de espinélio, e através da composição química das inclusões encontradas no lingotamento contínuo foi possível identificar em quais das corridas estudadas houve a presença de inclusões de aluminatos de cálcio formados no estado líquido. / In the present work it was studied 10 heats in two steelworks, of low alloyed steel for use in mechanical construction. From each heat were taken 9 samples, each one of them at end of one production stage: after deslagging in the ladle; before vacuum degassing; after vacuum degassing; after Al wire addiction; after CaSi wire addiction; after S wire addiction; after the end of tundish turbulence at continuously casting; 30 minutes after the end of tundish turbulence at continuously casting; and 60 minutes after the end of tundish turbulence at continuously casting. Samples were metallographic prepared and analyzed by scanning electronic microscopic (SEM) with energy dispersive X-ray spectroscopy (EDX), in order to identify the inclusions present in steel in each process stage. This allowed the founded inclusions in each process stage to be characterized and classified according to chemical composition and morphology. By comparing founded inclusions chemical composition at end of refining and continuous casting was possible to observe a tendency of formation of spinel inclusions, and by founded inclusions chemical composition in continuous casting was possible to identify in which studied heats there were presence calcium aluminates inclusions formed in the liquid state.

A utilização de argila como matéria-prima acompanha a evolução humana desde a Pré-história, ao longo do tempo o ser humano vem utilizando as argilas para produzir objetos variados, como vasos, estatuetas e tijolos. Nos dias atuais muitas indústrias utilizam os diferentes tipos de argilas encontradas na natureza. Neste trabalho foi utilizado um caulim proveniente da Bahia e o outro caulim proveniente de São Paulo. Os caulins foram caracterizados através das técnicas e ensaios de difração de raios X (DRX), microscopia eletrônica de varredura (MEV), espectroscopia por energia dispersiva (EDS), microscopia estereoscópica (MO), infravermelho (IV), análises térmicas (TG e DSC), fluorescência de raios X (FRX), análise química (IQ), análise granulométrica, área superficial (BET), inchamento de Foster, incorporação de solventes, capacidade de troca catiônica (CTC), ensaios cerâmicos, ensaio de adsorção, quantificação da matéria orgânica, ensaio de plasticidade, viscosidade Fann e umidade base seca e base úmida. Todos os resultados foram utilizados para realizar uma comparação entres as propriedades dos dois caulins selecionados para este estudo. Em seguida os caulins foram submetidos ao processo de organofilização. Os resultados mostram que as duas argilas são compostas pelo argilomineral caulinita, todos os resultados apresentaram-se compatíveis com argilas cauliníticas e a organofilização dos caulins foi comprovada principalmente pelos resultados do infravermelho (IV) e teste de inchamento de Foster. / The use of clay as raw material accompanies human evolution since the prehistory, over time humans have been using clays to produce various objects, such as vases, figurines and bricks. Now days many industries use different types of clays found in nature. The clays are formed by a claymineral or a mixture of various clayminerals, there is a certain content of alkali and alkaline earth elements, have low particle size and acquires plasticity when in contact with water, also have impurities such as organic matter, soluble salts, quartz particles, mica and other minerals, and some residual amorphous minerals. In this study was used a kaolin from Bahia and other kaolin from São Paulo. The Kaolins were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), stereoscopic microscopy (SM), infrared (IR) , thermal analysis, X-ray fluorescence (XRF), chemical analysis (CA), particle size analysis, surface area (BET), Foster swelling, incorporation of solvent, cation exchange capacity (CTC), ceramic tests, adsorption, organic matter, plasticity, Fann viscosity and humidity. All results were used to make a comparison between the two kaolins properties. Then the kaolins were subject to an organophilization process. The results show that both clays are composed of kaolinite with properties compatible with those of kaolins. Organophilization mainly been proven by the results of infrared (IR) and Foster swelling test.

Nesta dissertação, são apresentados os processos de caracterização, classificação e de compartimentação geomecânica dos maciços rochosos, com a utilização dos dados pertinentes às fases de estudos nos projetos de engenharia. Como área de pesquisa analisou-se os dados referentes aos estudos da fundação da barragem, de uma Usina Hidroelétrica, localizada no Rio Pelotas, entre os estados do Rio Grande do Sul (Margem esquerda) e Santa Catarina (Margem Direita) em um sítio constituído por uma seqüência de derrames basálticos da Formação Serra Geral na Bacia do Paraná. Este maciço revela-se verticalmente heterogêneo, constituído por uma seqüência de 15 (quinze) derrames (relativamente pouco espessos) que possuem distintas características tanto sobre os aspectos geomecânicos, estruturais e tectônicos; quanto da diferenciação litológica de cada um - que compreende a seqüência de basalto denso, basalto vesículo amigdaloidal e brecha basáltica. O intuito da pesquisa foi mostrar a caracterização do maciço abrangendo aspectos estratigráficos, litológicos, estruturais, tectônicos e geomecânicos, para que fosse possível a formulação da compartimentação e dos modelos geológicos e geomecânicos do maciço. Na composição da base de dados foi realizado um levantamento de campo por meio de investigações de superfície e subsuperfície, para que posteriormente fossem realizados os trabalhos de gabinete e as análises laboratoriais. Para o estabelecimento do modelo geológico orientou-se pelos dados litoestratigráficos, estruturais e tectônicos obtidos através dos mapeamentos de superfície e das investigações de subsuperfície. A compartimentação geomecânica foi composta por informações oriundas dos itens de caracterização do maciço (alteração, fraturamento, Rock qualitiy designation - RQD, e permeabilidade); e pela classificação geomecânica, quanto a esta, empregaram-se as metodologia Rock Mass Rating - RMR, Quality - Q e Geological Strength Index - GSI. O propósito dessa classificação visava estabelecer um paralelo entre os parâmetros metodológicos utilizados e os resultados obtidos - em que se notou uma grande dependência da compartimentação geomecânica ao modelo geológico. / In this dissertation, the processes of characterization, classification and geomechanical compartmentation of the rocky mass range are investigated with the utilization of data resulting from the study phases in engineering projects. As a research area, the data referring to the studies of the foundation of a hydroelectric power plant dam, located on Rio Pelotas, between the states of Rio Grande do Sul (left bank) and Santa Catarina (right bank) on a site formed by a sequence of basaltic flood of Serra Geral formation at the Paraná Basin have been analyzed. This rock mass range, vertically heterogeneous, is formed by a sequence of 15 (fifteen) floods (relatively little solid) which possess distinct characteristics on the geomechanical, structural and tectonic aspects, as well as on the lithological differentiation of each one - which includes the sequence of dense basalt, vesicles-amygdaloidal basalt and basaltic breach. The intention of the research was to show the characterization of the mass range, embracing stratigraphic, lithological, structural, tectonic and geomechanical aspects, so that it would be possible the formulation of the compartmentation and geological and geomechanical models of the mass range. In the database composítion, a field survey was carried out through surface and subsurface investigations, so that afterwards the laboratorial analysis could be accomplished. For the establishment of the geological model, the lithostratigraphic, structural and tectonic data have been examined, which have been obtained through the mapping of the surface and subsurface investigations. The geomechanical compartmentation was put together by the information resulting from the characterization items of the mountain range (alteration, fracture, Rock quality designation - RQD and permeability); and by the geomechanical classification; for that matter, the Rock Mass Rating - RMR, Quality - Q and Geological Strength Index - GSI methodologies have been employed. The purpose of this classification was to establish a parallel between the methodological parameters used and the results obtained - where a large dependence of the geomechanical compartmentation on the geological model had been observed.

Curcumina é um composto natural presente na Curcuma longa, que apresenta diversas atividades medicinais, porém sua baixa solubilidade limita sua aplicação médica. Para solucionar esse problema e viabilizar seu uso, diversas pesquisas no campo da nanotecnologia estão sendo feitas. Neste estudo foram obtidas nanopartículas de curcumina utilizando como solventes o etanol (E) e o clorofórmio (C), e através dos procedimentos de agitação magnética e sonicação. As nanopartículas foram caracterizadas por espalhamento de luz dinâmico (DLS), potencial Zeta, microscopia de força atômica (AFM) e pelas espectroscopias no infravermelho (FTIR), no ultravioleta/visível (UV-Vis) e de fluorescência. Foram feitos ensaios de solubilidade, fotodegradação e citotoxicidade. As nanopartículas obtidas com o solvente E e pelos processos de agitação e sonicação foram denominadas de NEA e NES, e com o solvente C de NCA e NCS, respectivamente. Teste inicial de liberação in vitro foi feito para a amostra NCA dispersas em gelatina com posterior recobrimento com Eudragit S100®; esse teste foi feito em HCl (pH 2,0) e tampão fosfato (pH 7,5). A morfologia dessas membranas recobertas ou não com Eudragit S100® foram analisadas por microscopia eletrônica de varredura (MEV). As nanopartículas tiveram um rendimento entre 60 e 78%. O resultado de DLS mostrou a obtenção de partículas nanométricas entre 189 e 248 nm para as NEA, NES e NCS e de 591 nm para NCA, com potencial Zeta acima de |25| mV para todas as amostras. As nanopartículas apresentaram uma fotodegradação mais lenta do que o produto comercial. As espectroscopias de FTIR, UV-Vis e fluorescência apresentaram bandas características da curcumina comercial, indicando que as nanopartículas têm as mesmas características químicas e físicas do bioativo. As nanopartículas mostraram um aumento na solubilidade de 37 a 56 vezes em relação à curcumina comercial. Os ensaios de citotoxicidade indicam que as nanopartículas não apresentaram toxicidade para a linhagem VERO, enquanto que para a linhagem HEp-2 ocasionaram morte celular. Assim, os procedimentos utilizados para o preparo das nanopartículas de curcumina foram eficientes, sendo que uso do solvente E mostrou ser o mais indicado para se obter nanopartículas. A morfologia por MEV das membranas de gelatina/NCA mostra um recobrimento uniforme com Eudragit S100®. Os testes iniciais de liberação in vitro mostraram que as nanopartículas de curcumina são protegidas pelo sistema em pH ácido e liberadas apenas quando em pH 7,5. / Curcumin is a natural compound present in Curcuma longa, which has several medicinal effects but due to its low solubility, its medical application gets constrained. To solve this problem and make it feasible to use, several studies are being made in the nanotechnology field. In this study curcumin nanoparticles were obtained using different solvents, ethanol (E) and chloroform (C), with two procedures, magnetic stirring and sonication. The nanoparticles were characterized by dynamic light scattering (DLS), Zeta potential, atomic force microscopy (AFM) and by infrared spectroscopy (FTIR), ultraviolet/visible spectroscopy (UV-vis), fluorescence spectroscopy. Solubility, photodegradation and cytotoxicity trials were made. The nanoparticles were named NEA and NES when prepared with E solvent, by magnetic stirring and sonication processes, and named NCA and NCS with C solvent, respectively. A preliminary in vitro release test was made with the NCA sample. It was dispersed in gelatin with the Eudragit S100® coating; this release test was done in HCl (pH 2.0) and phosphate buffer (pH 7.5). The membranes with and without Eudragit S100® coating were morphologically analyzed by scanning electron microscopy (SEM). The nanoparticles yield between 60 and 78%. The DLS results showed nanometric particles between 189 and 248 nm for NEA, NES and NCS samples and 591 nm for NCA sample. Moreover, a Zeta potential superior to |25| mV was obtained for all samples. The nanoparticles showed a slower photodegradation compared to the commercial curcumin. The FTIR, UV-vis and fluorescence spectroscopy resulted in characteristic bands, indicating that these nanoparticles have the same chemical and physical characteristics of the commercial curcumin. Likewise, an increase in solubility of 37 to 56 times was observed in comparison with the commercial product. Furthermore, the cytotoxicity assays suggested no toxicity to VERO cell lineage, while death for HEp-2 cell lineage. The procedures used for the curcumin nanoparticles preparation were efficient; however, the most suitable nanoparticles were obtained with E solvent. The morphology by SEM of gelatin/NCA membranes indicates a uniform coating with Eudragit S100®. In vitro release tests showed that curcumin nanoparticles were protected by this system at acid pH and released at pH 7.5.

The present research seeks to characterization of an additively manufactured and heat-treated Ti-xMn gradient alloy, a binary system that has largely been unexplored. In order to rapidly assess this binary system, compositionally graded Ti-xMn (0<x<15 wt%) specimens were fabricated using the LENS (Laser Engineered Net Shaping) and were subsequently heat-treated and characterized using a wide range of techniques. Microstructural changes with respect to the change in thermal treatments, hardness and chemical composition were observed and will be presented. These include assessments of both continuous cooling, leading to observations of both equilibrium and metastable phases, including the titanium martensites, and to direct aging studies looking for composition regimes that produce highly refined alpha precipitates – a subject of great interest given recent understandings of non-classical nucleation and growth mechanisms. The samples were characterized using SEM, EDS, TEM, and XRD and the properties probed using a Vickers Microhardness tester.

As commercially manufactured nanomaterials become more commonplace, they have the potential to enter ecological and biological environments sometime during their lifecycle of production, distribution, use or disposal. Despite rapid advances in the production and application of nanomaterials, little is known about how nanomaterials may interact with the environment or affect human health. This research investigates an environmental application of nanomaterials and characterizes the physicochemical properties of commonly manufactured nanomaterials in environmental health and safety studies. Characterization of nanomaterials for applications and environmental health and safety studies is essential in order to understand how physicochemical properties correlate with chemical, ecological, or biological response or lack of response. Full characterization includes determining the bulk and surface properties of nanomaterials. Bulk characterization methods examine the shape, size, phase, electronic structure and crystallinity, and surface characterization methods include surface area, arrangement of surface atoms, surface electronic structure, surface composition and functionality. This work investigates the selective catalytic reduction (SCR) of NO2 to N2 and O2 with ammonia on nanocrystalline NaY, Aldrich NaY and nanocrystalline CuY using in situ Fourier transform infrared (FTIR) spectroscopy. It was determined that the kinetics of SCR were 30% faster on nanocrystalline NaY compared to commercial NaY due to an increase in external surface area and external surface reactivity. Copper-cation exchanged nanocrystalline Y resulted in an additional increase in the rate of SCR as well as distinct NO2 and NH3 adsorption sites associated with the copper cation. These superior materials for reducing NOx could contribute to a cleaner environment. This work consists of characterization of commonly manufactured or synthesized nanomaterials and studies of nanomaterials in specific environmental conditions. Bulk and surface characterization techniques were used to examine carbon nanotubes, titanium dioxide nanoparticles, bare silver nanoparticles and polymer-coated silver nanoparticles, and copper nanoparticles. Lithium titanate nanomaterial was collected from a manufacturing facility was also characterized to identify occupational health risks. Particle size distribution measurements and chemical composition data showed the lithium titanate nanomaterial forms larger micrometer agglomerates, while the nanoparticles present were due to incidental processes. A unique approach was applied to study particle size during dissolution of nanoparticles in aqueous and acidic conditions. An electrospray coupled to a scanning mobility particle sizer (ES-SMPS) was used to determine the particle size distribution (PSD) of bare silver nanoparticles in nitric acid and copper nanoparticles in hydrochloric acid. The results show unique, size-dependent dissolution behavior for the nanoparticles relative to their micrometer sized counterparts. This research shows size-dependent properties of nanomaterials can influence how they will be transported and transformed in specific environments, and the behavior of larger sized materials cannot be used to predict nanomaterial behavior. The type of nanomaterial and the media it enters are important factors for determining the fate of the nanomaterial. These studies will be important when considering measures for exposure control and environmental remediation of nanomaterials.

Orientador: Rita C. S. Maimoni-Rodella / Banca: Maria Tereza Zugliani Toniato / Banca: Flávio Schlittler / Resumo: Realizou-se a caracterização, mapeamento e diagnóstico de fragmentos de vegetação remanescente de Floresta Estacional Semidecidual e de Cerrado, localizados no âmbito do Jardim Botânico do Instituto de Biociências, Universidade Estadual Paulista - UNESP, Campus de Botucatu, situados no Distrito de Rubião Júnior, Município de Botucatu, Estado de São Paulo, e em seu entorno. foi utilizado diagrama de perfil para a caracterização do tipo vegetacional das áreas; listagem florística, realizada por levantamento expedito e consultas à literatura e ao material incorporado ao Herbário "Irina Delanova de Gemtchujnicov" (BOTU) do Instituto de Biociências da UNESP-Botucatu. Para o diagnóstico do estado de degradação de cada fragmento foi aplicado um protocolo de avaliação. No total foram descritos seis fragmentos de Floresta Estacional Semidecidual quatro destes localizados no Jardim Botânico e dois no seu entorno. A fisionomia dos fragmentos não apresentou variações acentuadas, sendo que os aspectos mais evidentes foram a diferença na densidade da vegetação, sendo a Mata do Butignoli a mais densa com maior abundância de Eu/c'1Je edulis (palmito-juçara). Houve maior ocorrência de árvores mortas nas áreas do Jardim Botânico. As diferenças na densidade observadas entre os estratos provavelmente sejam decorrência da maior perturbação antrópica ocorrida nos fragmentos mais facilmente acessíveis, como é o caso das áreas do Jardim Botânico que são freqüentemente visitadas e utilizadas pela comunidade de estudantes e população em geral. A Mata do Butignoli e o Morro de Rubião Júnior são mais distantes e têm acesso dificultado pela topografia, o que pode justificar sua maior preservação no momento. Os quatro fragmentos de Cerrado, descritos no Distrito de Rubião Júnior, apresentaram variações, evidenciando que somente um deles apresenta-se mais estruturado... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study performed a characterization, mapping and diagnosis of Semi-deciduos Forest and Cerrado vegetation remnants, located in the in the Biosciences Institute Botanical Garden area and its vicinities, in the State University of São Paulo, Botucatu, state of São Paulo. Profile diagrams were used for the vegetation type characterization. A floristic list was provided through expedite survey and study of literature and material collected by the "Irina Delanova Gemtchujnicov" herbarium ofBiosciences Institute ofUNESP-Botucatu. A evaluation protocol was used for degradation diagnosis. Six remnants of semideciduos forest were described, four located in the Botanical garden and two in its vicinities. The remnants physiognomy did not presented significant variation and the more evident aspects were the difference in vegetation density. The Butignoli remnant was the more dense and abundant in Euterpe edulis. The biggest incidence of dead trees was in the Botanicul Garden area. The difference in density observed was probably due to the anthropic action occurred in th~ more accessible remnants, like in the Botanical Garden area that are frequently visited and used by students and population. The Butignoli remnant and Rubião Junior Hill are more distant and are difficult to access due to the topography, what may explain its better preservation. The four Cerrado remnants described presented variations, evidencing that only one of them is more structured. There are evidences that the other remnants may be considered degraded. These remnants presented low floristic similarities, with few species in common, even though they are closely located. The remnants studied, although with cJear perturbations, are significant representatives of the original vegetation and need to be preserved because, besides their ecologic importance, they may serve as natural laboratories... (Complete abstract click electronic access below) / Mestre

This work aimed to develop in a two-step strategy the deoxygenation of benzoic acid as a new probe reaction of the oxidation catalysts "at work". This choice was based on the experimental fact that the distribution of the potential main products, namely benzaldehyde, toluene and benzene depends on the presence and the mutual disposition of oxygen vacancies at the surface of the oxide catalysts. Indeed, it is claimed in the literature that single oxygen vacancies selectively produces benzaldehyde, twin oxygen vacancies (i.e. two oxygen vacancies separated by about 2Å) induce the formation of toluene while the benzene production does not need the presence of any oxygen vacancies. Two molybdenum based catalytic systems were chosen to test the new probe reaction : the molybdenum (sub)oxides and the metal molybdates. By the way of a new and original coupling between the probe reaction and the oxidation of propylene, we planned to correlate in real time the formation of the superficial oxygen vacancies monitored by the deoxygenation of benzoic acid and the activity in an oxidation reaction. Such an experimental coupling is a promising and a powerful tool which allows the fine characterization of the active catalytic site at work in an oxidation reaction.