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Solução de um modelo de vértices assimétrico de três estados
(Universidade Federal de São Carlos, 2005-03-29)
Melo, Cláudio Silva de
;
Martins, Márcio José
;
https://lattes.cnpq.br/1875815921495261
In this work we first review some of the techniques relevant to the theory of two-dimensional integrable models. We apply the Quantum Inverse Scattering approach to a class of three-state vertex model with both closed and open boundaries. The respective transfer matrices eigenvalues and eigenvectors are determined by the algebraic Bethe ansatz method.
Estudo experimental da deformação ao longo do tempo de lajes contínuas e simplesmente apoiadas executadas com vigotas pré-moldadas de concreto
(Universidade Federal de São Carlos, 2005-03-29)
Kataoka, Luciana Tiemi
;
Carvalho, Roberto Chust
;
https://lattes.cnpq.br/3633394168236221
This research deals with the experimental investigation of time dependent deformations in partially precast floors with composite beam-and-block floor systems made with reinforced concrete lattice joist through the measurement of deflections of prototypes with real dimensions. It is a continuation of several researches of composite beam-and-block floor systems done in Universidade Federal de São Carlos. Besides the accompanied measurement deflections of four already existents prototypes, with ages of three and a half years, it was studied eight new prototypes built in pairs. Four prototypes are localized in an acclimatized room in other to keep the values of temperature and humidity constant, and the other four prototypes, with identical characteristics, localized inside of a covered area where the temperature and humidity vary. The climatic variations were measured and analyzed in the evaluation of time dependent deformation. In the new prototypes the strain were also accompanied in the concrete and in the reinforcement, as well as their influences in time dependent deformation. Simultaneously to the experimental study, models for predicting creep are tested for prediction of deflections along the time, including the new version of Brazilian Code for Structural Concrete (NBR6118:2003). The research also establishes the ratio of long-term deflections (infinite) to the instantaneous deformation and it evaluates how the deformation develops in composite beamand- block floor systems of different supports, wherein statically and hyperstatically structures were studied. As a conclusion in this research, conforming in others already done by the study group, it has been found the results give strongly indication that the composite beam-and-block floor systems deformations are a decisive factor in design and that the shrinkage of the concrete increases this effect.
Definição de um indicador para avaliar a acessibilidade dos alunos da zona rural às escolas da zona urbana
(Universidade Federal de São Carlos, 2005-03-29)
Pegoretti, Michela Sagrillo
;
Sanches, Suely da Penha
;
https://lattes.cnpq.br/3857424839674606
The main objective of this work was to establish an indicator to evaluate students accessibility from rural to urban areas. It involves the broad issue of rural versus urban dichotomy and the evolution of social and spatial segregation process in the cities, which reaches the rural area, isolsting it and restricting people s access to different activities. It also establishes the importance of cities accessibility improvement by rural zones inhabitants, through means of transportation, as a way of mitigating opportunity difference that reach people who live in the field, specially those who are attending school. This paper analyses the situation of rural school transportation in Brazil, identifying the most relevant attributes that interfere in the accessibility: children walking distances, travel time and characteristics of the roads and safety/comfort in the vehicles. The accessibility patterns were evaluated in regard to the trips from the residence to the bus stop (walk trip) and the trips from the bus stop to the schools (by motorized vehicles). The methodology for the research development consisted on the use of a multicriterial evaluation method, composed by four steps: attributes choice, determining attribute importance, normalization and combination. In one of these steps, a survey was made with 120 (one hundred twenty) professionals who act on education and transportation areas to evaluate the importance of the accessibility attributes and higher acceptable distance values travelled by foot and the travel time to school. The case study was developed in the city of São Carlos, where the defined indicator was applied to seven (07) transport lines in the afternoon period on the district of Água Vermelha. The final research result, generated on TransCAD, is shown by means of a map of multicriterial accessibility of the chosen region. The analyses realized about the results, prove that more distant boarding places from rural schools do not have, as a rule, lower levels of accessibility and that minimizing students walking distances from home to the boarding stops is a very important point to be considered on the planning of rural school transportation.
Fenologia, maturação fisiológica e aspectos da germinação de sementes de Platymiscium floribundum Vog. no Parque Estadual Alberto Löfgren, Instituto Florestal, São Paulo - SP
(Universidade Federal de São Carlos, 2005-03-30)
Silva, Maria Conceição Carvalho da
;
Perez, Sonia Cristina Juliano Gualtieri de Andrade
;
https://lattes.cnpq.br/9973185407856723
In this work was evaluated the seeds and fruits development of Plathymiscium floribundum Vog. and associated it with the phenophases, in order to get seeds with high physiological quality. The phenological observations were carried out using 20 matrix from Parque Estadual Alberto Löfgren belong to Instituto Florestal - SP, since January 2001 until December 2003. For the maturation study fruits and seeds were collected, and were realized determinations as physical, chemical parameters, physiology and color patterns. The data recorded showed that the flower and fruit production occurred at the spring, during the rainy season. Besides it, in several trees the flower production was not followed by fruit development. The total abscision of these organs was observed. The seed production occurred in periods longer than one year, and was restricted to some individuals. The fruits produced at 2002 did not reach the mature stage, and only two matrix produced flowers and fruits. During 2003 all the fruits were detached by abscision. The fruit color and the dry weight of the fruits and seeds are good indicators for the physiology maturity of the seeds. This work also evaluated the vigor of Plathymiscium floribundum Vog. seeds, fresh harvest with 8,97% of moisture and stored during 75 days at room environment inside paper bags. The determinations were done each 15 days and included: moisture content, rate and percentage germination, electrical conductivity (EC) accelerated aging (AA) and tetrazolium test (TZ). The experiments were carried out with four replications of 15 seeds. For the EC test the seeds were weight and after were put inside plastic cups with 75 mL of distilled water, during 24h at 25oC. The values obtained differ after storage during 15 days. The AA was realized at 40oC and 100% of R.U. during 6 and 24 h and a difference was only registered after storage during 75 days. For the TZ test the seeds were pre imbibed during 24h at 25oC, without pericarp and immersed in solution 1% concentrated. The seeds presented high physiological quality, and the decrease only occurred at the last storage period. In this research was also evaluated the maximum tolerance limits for water and salt stresses on Platymiscium floribundum seeds, imbibed in KCl, NaCl, mannitol and PEG 6000 solutions for salt and water stress, respectively with osmotic potentials: 0; -0,2; -0,4; -0,6; -0,8; and -1,0MPa. The experiments were carried out with four replications of 20 seeds germinated at 27°C, and continuous light The obtained data were submitted to variance analysis and Tukey test. A significance reduction on rate and percentage germination was registered at -0,2MPa and -0,6MPa, respectively, using mannitol solutions. When PEG solutions were used a significantly reduction on rate and germination percentage was at -0,4 MPa. When KCl and NaCl solutions were used a gradual reduction on germination percentage occurred. The highest values of rate and germination percentage were registered for seeds germinated in mannitol solutions, in all osmotic potentials. In relation to salt stress the reductions on rate and germination percentage occurred slightly, in contrast to water stress. A significantly decrease on germination percentage was verified at -0,4MPa, for both salt solutions. In relation to germination rate, the reduction was first detected at -0,6MPa and -0,8MPa for KCl and NaCl solutions, respectively. The maximal tolerance limit was the same, between -1,0 and -1,2MPa, for salt and water stress.
Modelagem de dados de sobrevivência via modelo de risco logístico generalizado
(Universidade Federal de São Carlos, 2005-03-30)
Cremasco, Caroline Pires
;
Louzada Neto, Francisco
;
https://lattes.cnpq.br/0994050156415890
;
https://lattes.cnpq.br/5339144730881561
The modeling of data of survival with the presence of covariáveis by means of the risk function has been each used time more had the easiness of interpretation One of the examples most important of risk models is the model of proportional risks considered by Cox (1972). However, this model assumes the proportionality enters the risk functions in diLerent levels of the covariáveis. To accomodate situations where the model of proportional risks is not adjusted, some types of notproportional models are being developed, as the model of sped up imperfection, considered for Prentice (1978), the model of hybrid risk of Etezadi-Amoli and Ciampi (1987) and the generalized models of hybrid risk of Louzada-Neto (1997 and 1999). In this work we explore an one new family parametric of model of dependent not-proportional risk of the time (McKenzie, 1999). This model is based on the generalization of the usual logistic function and is motivated, in part, for the necessity of if considering the eLect of the time in the modeling, and, in part, for the preference in if considering a parametric structure for the risk function. Some inferenciais procedures related this new family of models are presented.The modeling of data of survival with the presence of covariáveis by means of the risk function has been each used time more had the easiness of interpretation One of the examples most important of risk models is the model of proportional risks considered by Cox (1972). However, this model assumes the proportionality enters the risk functions in diLerent levels of the covariáveis. To accomodate situations where the model of proportional risks is not adjusted, some types of notproportional models are being developed, as the model of sped up imperfection, considered for Prentice (1978), the model of hybrid risk of Etezadi-Amoli and Ciampi (1987) and the generalized models of hybrid risk of Louzada-Neto (1997 and 1999). In this work we explore an one new family parametric of model of dependent not-proportional risk of the time (McKenzie, 1999). This model is based on the generalization of the usual logistic function and is motivated, in part, for the necessity of if considering the eLect of the time in the modeling, and, in part, for the preference in if considering a parametric structure for the risk function. Some inferenciais procedures related this new family of models are presented.
Representações sociais do trabalho carcerário feminino
(Universidade Federal de São Carlos, 2005-03-31)
Moki, Michelle Peixoto
;
Mancuso, Maria Inês Rauter
This dissertation: The social representations about the feminine prison labor aims at collecting and analysing the social representations the women who are prisoners (women inmates) and the ones who work at prison, such as guards, teachers and principals of the Penitenciária Feminina da Capital (São Paulo SP) have about work. The work is considered by the prisoners as an opportunity to earn money and at the same time as a brief scape from their reality. Besides, the prison labor has a variety of values which are associated to values expressed by the ones who are not at prison. Therefore the prison labor is conceived as something highly positive which gives the prisoners the citizenship passport. Even when the feminine prisoners do not agree with the work at prison, they are forced to work as the work is conceptualized as something which might rescue the criminals, offering them the possibility of being reintegrated in society.
Efeitos de diferentes intervenções nutricionais e do exercício físico sobre a regulação hormonal da ingestão alimentar e o metabolismo lipídico em ratos
(Universidade Federal de São Carlos, 2005-03-31)
Cheik, Nadia Carla
;
Dâmaso, Ana Raimunda
;
https://lattes.cnpq.br/8198400959291700
;
https://lattes.cnpq.br/2879799494543129
The prevalence of obesity is increasing worldwide, indicating that environmental and behavioral aspects play an important causal role. Among the environmental influences, the percentage of fat energy in everyday diet and the lack of physical activity are two important factors, so the mechanisms that control food intake and body weight are essential in public health. The adipose tissue is regulated by several hormones and neuropeptides. Two of these, the circulating peptide hormones leptin and ghrelin, have actions that include reciprocal effects on appetite-regulating neurons in the hypothalamus. This study aimed to observe whether the effects of continuos fedding with a palatable hyperlipidic diet and cycling this diet with a chow one and also entends to design the effects of exercise on these diet regimens.The animals (rats) were assigned to six differents experimental groups:sedentary rats fed with chow diet(SP); exercised rats fed with chow diet(TP); sedentary rats fed with a palatable hyperlipidic diet(SH); exercised rats fed with a palatable hyperlipidic diet(TH); sedentary rats fed with food cycles, alternating weekly the chow diet wih hyperlipidic one(SC); and exercised rats fed with food cycles(TC). The data showed that the two hyperlipidic diet regimens significantly increased RET and EPI weights, area and diameter of adiposity cells, promoted hyperinsulinemia, hyperleptinemia and decreased significantly lipogenesis rate in RET and EPI, showed also percentual reduction in ghrelin levels, but didn t affect the lipolysis rate. In addition, the present investigation showed that chronic exercise decreased body weight gain and adiposity and attenuated insulin, leptin levels in both high-fat feeding regimens, also reduction in ghrelin levels in TP and increased the lipolysis rate under all regimens, excepting in food cycle treatment. Results suggest that diet and exercise affected serum levels anorexigenic and orexigenic hormones and the lipid metabolism.
A fauna de Braconidae (Hymenoptera: Ichneumonoidea) na região de Campos do Jordão, São Paulo, Brasil
(Universidade Federal de São Carlos, 2005-03-31)
Gomes, Silvana Angélica Gama
;
Dias, Angélica Maria Penteado Martins
;
https://lattes.cnpq.br/8637344058859147
This work had as main objective to carry through a study of the Braconidae (Hymenoptera) fauna in Campos do Jordão, SP, using Malaise traps and "sweeping" at the vegetation in 15 points in different altitudes (600 to 2000 m). About 3580 specimens, distributed in 23 subfamilies, 103 genera and 1420 morphospecies have been collected during the four collects carried through two dry seasons and two rain seasons, from November, 2001 to September, 2002. We have obtained climate data and vegetation data, in each point, to characterize and to relate them with the frequency of occurrence, richness and diversity of the Braconidae fauna. The greatest density and diversity have occurred during the rain season and the most abundant groups, in both seasons, were the Microgastrinae, Helconinae, Doryctinae and Alysiinae. Statistical analyses have indicated that the frequency of occurrence of some Braconidae groups was influenced by the different altitude. The greatest Braconidae diversity occurred at the1500 m of altitude and the greatest equitability at the 1300 m, demonstrating the preference for points with opened areas, where the luminosity is high, and contribute to the development of the vegetation, that is the food source to its hosts. The asymptote phase of the genera richness was not reached in none of the sampled points. The flight species phenology of the 23 subfamilies was also studied. The more commom subfamilies were the coinobiont Microgastrinae and the idiobiont Doryctinae. All the collected parasitoids have presented two peaks of occurrence at the same time, November/December (2001) and September/October (2002). The females were more commom than the males and they presented their peaks of ocurrence at same time. The coinobionts and idiobionts species had presented an increase in the abundance during the periods when the temperature and the rainfall had been higher. A new Doryctinae genus, a new Heterospathius and Helconichia species were described and illustrated. The Campos do Jordão region is favorable to the development and maintenance of the Braconidae fauna and therefore its preservation must be considered.
Avaliação de limiar e máximo conforto auditivo por meio de procedimentos operantes com crianças surdas prélinguais submetidas a implante coclear
(Universidade Federal de São Carlos, 2005-03-31)
Silva, Wagner Rogério da
;
Souza, Deisy das Graças de
;
https://lattes.cnpq.br/4404800720856419
;
https://lattes.cnpq.br/3170433350044049
The cochlear implant is a prosthetic electric device that is implanted through surgery. I has the propose of substituting the cochlear functions allowing thus, the individuals with pre and post-linguistic neurosensorial deafness to begin to detect environmental sounds. One of the necessary procedures to help someone to develop hearing skills after the implant is to trace electrodes, which is a procedure that basically consist of determining measures of threshold and maximum hearing comfort for each implanted electrode. In order to obtain these within the clinical practice, the oral skills of the individuals with implant must be considered. The precision of these measures become very compromised among implanted children with pre-linguist deafness, due to the deficit of their speech capacity. The purpose of the present study is to propose an evaluation of two procedures that attempt to obtain measures of both, hearing threshold and maximum hearing comfort without using neither, directions or verbal answers. The study consist de two experiments composed by seven pre-linguist children with profoundly neurosensorial deafness, which have acquired the Nucleus 24® cochlear implant system . In one of de procedures, a simple operant discrimination between the presence and absence of de hearing stimulus was established during the training phase. Following, a testing phase was introduced in order to determine the hearing threshold to assess the discrimination loss through a descendant scale, which measures the variation intensity of the electric stimulus (Experiment 1). In the other procedure, it was established that during the electric stimulation of the training phase, an answer could stop the stimulus while no answer produce a positive reinforcement. Next, the intensity of the stimulus was modified during the test phase in ascendant scales with or without an answer, in order to determine whether or not the stimulus was comfortable to the subject (Experiment 2). In both procedures, the electric stimulation was realized through an electrode located in the cochlear medial region. Electro-physiologic measures of the ECAP and ESR were evaluated in an additive form within the same date that the operational procedures were realized. Also, measures of the hearing threshold obtained during clinical approach of the last evaluation, preceding the beginning of the experiments, were registered. All of these measures were compared to results obtained from de operant procedures. The results demonstrated in the Experiment 1, all of the participants learned the taught discrimination and how to use this skill during the variation of the electric stimulation in descendant scales. This experiment was also used to indicate hearing threshold measures with consistence to all of the participants. In the Experiment 2, five of the seven participants mastered the procedure; however, the results indicate that the order two participants learned that the answer would interrupt an electric stimulus and its absence would lead to the reinforcement. Thus, their performance aimed for identification of the consistence level of the maximum comfort in ascendant scales of variation. The training phase was not successful with the other participants, compromising then the consistence of the performance demonstrated during the testing phase; nonetheless, the measures are suggested for them as well. Concerning the relationship among the operant measures and the other measures betaken in the study, the results show that measures of operant threshold are similar to or smaller than the measures obtained through clinical methods. Regarding the maximum comfort values as the most relevant data. It has been emphasized that the two participants that fulfilled the expected performance in the procedure, demonstrated stapedial reflex values (ESR) similar to the obtained from operant form. The data suggest initial evidence that the operant procedure can contribute to the realization of tracing electrodes with larger precision among pre-linguistic children with implants.
Contribuições aos estudos citogenéticos em algumas espécies de 5 famílias de Siluriformes do rio São Francisco
(Universidade Federal de São Carlos, 2005-04-01)
Garcia, Caroline
;
Moreira Filho, Orlando
;
https://lattes.cnpq.br/3927076022470557
Cytogenetic studies involving representatives of the order Siluriformes found in the São Francisco River basin continue practically inexistent. Therefore, the main objective of the present work was to contribute to the cytogenetical knowledge of the fish species belonging to the following families: Auchenipteridae, Doradidae, Heptapteridae, Pimelodidae and Pseudopimelodidae, all found in the São Francisco River in the Três Marias region MG. In order to accomplish this, conventional chromosome analysis, different bandings and fluorescent in situ hybridization with 5S AND 18S rDNA probes were used. A great part of the cytogenetical data obtained consists in the first chromosomal characterization of many of the analyzed species, emphasizing the need for more studies of this sort within this group. A few chromosomal evolution tendencies were also detected for species that already possessed previous cytogenetic information, which permits a larger comprehension of the differentiation processes and karyotypic evolution. The data here presented give clues regarding the great diversity of the ichthyofauna of the São Francisco River and regarding the possible effects of factors that influence in the diversification and in the high degree of endemism of the fish belonging to this basin.
Estudo da eficiência de coleta em Lavador Venturi com injeção de líquido por multi-orifícios
(Universidade Federal de São Carlos, 2005-04-04)
Ribeiro, Ana Paula Rodrigues Alves
;
Coury, José Renato
This work had for objective to study the influence of the variables liquid flow, throat length, number of orifices and gas velocity in the throat in the collection efficiency of a Venturi scrubber. As particulate matter to be removed from the gas, a phosphate concentrate of density 2.9 g/cm3 was used, fed at a mass flow rate of 3.16 g/min. The experimental system used in this work consisted of a Venturi scrubber of rectangular geometry operating horizontally, with liquid injection through 1 to 5 orifices with 1 diameter mm each, distributed in the scrubber throat. For the experiments, two experimental planning were used, with three factors in three different levels. In the first planning was studied the influence of the variables liquid flow in the range from 300 to 900 cm3/min, throat length in the range from 6.5 to 18.5 cm and number of orifices in the range from 1 to 5 holes; the gas velocity in the throat was kept constant at value of 69.33 m/s. In the second planning was studied the influence of the variable gas velocity in the throat in the range from 58.66 to 69.33 m/s, with the liquid injected by a single orifice. It was verified that the overall collection efficiency of the Venturi scrubber varied within the range from 50 to 91%, for the studied conditions in the first planning. A tendency of increase of the efficiency was observed with the increase of the liquid flow and of the throat length. As for the number of orifices, a better performance of the scrubber was verified when only 1 orifice was used. It was verified that the overall collection efficiency of the Venturi scrubber varied within the range from 52 to 93%, for the studied conditions in the second planning. Was observed that the increase in the gas velocity in the throat resulted in an increase in the overall collection efficiency. The predictions of the classical equations for collection efficiency of Johnstone et al. (1954), Calvert et al. (1972) and Leith and Cooper (1980) were compared to the experimental values. It was observed that both for the experimental results and for the models that the global efficiency increases with the increase of the liquid flow. However, it was verified that the models of Johnstone et al. and Calvert et al. underestimated the values of global efficiency obtained experimentally while the model of Leith and Cooper overestimated them. Therefore, it became necessary to adjust a model to the experimental points. It was taken as departure point the model of Calvert et al., for being a classic model and because it is widely used industrially. An adjustment equation for the empiric factor f using the experimental data was then performed. As it was verified in previous tests that the variable throat length is relevant in the collection efficiency and the same does not appear in the equation proposed by Calvert et al., it was decided to adjust an equation of f in function as a function of LG as f= 3005 , 0 . 5161 , 0 G L . The validity of the adjustment was verified by the good agreement of the experimental values of efficiency observed experimentally with the predicted values by the modified Calvert model.
Regularização fundiária na cidade de Piracicaba-SP: ações e conflitos
(Universidade Federal de São Carlos, 2005-04-06)
Funes, Silvia Maria Morales
;
Shimbo, Ioshiaqui
;
https://lattes.cnpq.br/6315114291031702
This work treats the issue of the land regularization of shantytowns, which, analyzed as a wider subject, also includes urban and juridical interventions. This research focused on the difficulties found in the development and conclusion of the land regularization legal processes, specially the juridical matter, in other words, the possession or property of the land, which the occupants demand so much. For an empirical approach, we studied Piracicaba, a town in the state of São Paulo, Brazil. On the subject of shantytowns, Piracicaba is different from most of the average sized towns in the country, both in quantity and urban location. While most of them have around 20% of their populations living in shanty towns, precarious urban outline and lack of infra-structure, the population that lives in shanty towns in Piracicaba is 5%, most of their nuclei present a reasonable urban outline and, at least, they have access to basic infra-structure. The hypothesis that led the research was that the legal processes of land regularization in shanty towns in Piracicaba were not concluded because of the absence of an inhabitation public policy, that included the land regularization, in which conditioning factors for the formulation and implementation of the legal processes are essentially the elaboration and materialization of the legislation, the existence of institutional stability, the continuance of administrative actions when there is a change in the government, financial viability, and the necessity of the participation of the population. To verify the hypothesis, we have picked, as studies of cases, three nuclei of shantytowns, among the fourty existent in Piracicaba, verifying the evidences that occurred in each regularization legal process that intercepted their conclusions. The period of analysis happens from the beginning of 1991 to the end of 2004. The methodology included bibliographical revision of the literature and the study of the legislation related to the subject, the documental analysis of the empirical processes found in the municipal bodies, interviews, the elaboration of a chart showing the evidences that happened in the three legal processes that were studied, and the organization and analysis of the information obtained for the hypothesis verification. At the end, we present the final considerations, showing that the initial hypothesis was confirmed.
Análise em fluxo e análise in situ como estratégias de melhoramento da seqüência analítica de amostras agronômicas
(Universidade Federal de São Carlos, 2005-04-06)
Lemos, Sherlan Guimarães
;
Nogueira, Ana Rita de Araújo
;
https://lattes.cnpq.br/7034773971317045
The present work discusses the use of alternative approaches for the improvement of the agronomic sample analytical pathway. It was focused on the elimination of the sampling step, with the in situ soil analysis, or in the measurement step with the adoption of flow analysis procedures, with the development of two analytical systems. The first one was employed in the total nitrogen and its inorganic forms determination in plant and soil samples, based on the Berthelot reaction. The second flow analysis system was developed for phosphorous speciation in seeds and grains samples used in animal nutrition by means a cobalt metallic electrode. For the elimination of the sampling step in the process of soil analysis, an analytical probe prototype was developed (hardware probe, sensors and electronic instrumentation and software algorithms for acquirement, processing, conversion, storage and data transfer) by using PVC membrane ion-selective sensors suitable to be inserted into soils for obtaining in situ and real time information of nutrient assimilation on agricultural soils. Parameters as pH and availability of some nutrients (K+; N, as NO3 - and NH4 +; Ca2+ and P, as H2PO4 -/ HPO4 2-) were evaluated in this stage. Although more systematic studies are needed, the results showed good responses of the studied sensors, and the great applicability of the developed instrumentation in the fertility irrigation monitoring, helping to establish rational processes in agricultural systems.
Determinação de As, Sb e Se em material agronômico por espectrometria de emissão óptica acoplada a plasma induzido com geração de hidretos (HG-ICP-OES)
(Universidade Federal de São Carlos, 2005-04-07)
Crispino, Carla Cripa
;
Nogueira, Ana Rita de Araújo
;
https://lattes.cnpq.br/7034773971317045
With the objective to attain maximum productivity with small costs, organic and inorganic chemical parameters are used to evaluate and monitoring crops and animals development. Inorganic amounts in agronomic samples have great importance in the production evaluation. Some of elements in those samples could be an indicative of quality, owing to their requirement (Se) or toxicity (As, Sb), even when they are present in µg kg-1 levels, needing a technique with high sensibility for quantification. The aim of this work was the development of a simple system of hydride generation by continuous flow combined with an inductively coupled plasma optical emission spectrometry for simultaneous determination of As, Sb and Se in agronomic samples. The work attained to a gas-liquid separator development, and an experimental planning to established the chemical and instrumental conditions of hydride generation. The HCl, NaBH4 and KI concentrations, such as the R.F. power, carrier gas flow and the viewing height, were evaluated besides the study of a more appropriate sample preparation. Limits of detection of the proposed system were 0.1 µg L-1 for As, Sb and Se and the limits of quantification were 0.3, 0.2 and 0.2 µg L-1 for As, Sb and Se respectively with RSD smaller than 10% and 30 samples per hour of reading speed. In view to observe the accuracy, four different kinds of samples forage and bovine-derived samples (blood, viscera and semen) were spiking with analytes concentration in the µg L-1 level. Recoveries around 77 to 112% were found. The results present the possibility to use the proposed system in agronomic projects developed with the objective to determine essential and toxic analytes in different kinds of feed and animal samples, contributing to evaluation of nutritional demands and the increase of efficiency in the bovine production systems.
Catalisadores de Ni/Al2O3 promovidos com Au e Ag aplicados à reforma a vapor do metano
(Universidade Federal de São Carlos, 2005-04-08)
Rocha, Kleper de Oliveira
;
Bueno, José Maria Corrêa
;
https://lattes.cnpq.br/0157452280626031
15%Ni/Al2O3 catalysts was obtained by impregnation with Ni(NO3)2 aqueous solution and promoted with Au and Ag. The Au was successively impregnated with aqueous solution of [Au(NH3)4](NO3)3. The Ag was coimpregnated with aqueous solution of AgNO3- Ni(NO3)2. The effect of Ag and Au on the catalytic behavior of Ni/Al2O3 catalysts in the reaction of steam reforming of CH4 was elucidate. The catalysts were characterized by temperatureprogrammed reduction (TPR), temperature-programmed dessorption of H2 (TPDH2) and Fourier transform infrared spectroscopy (FTIR) of CO adsorption. TPR results indicated that NiO is in weak interaction with support and the temperature reduction of NiO is independent of Ag and Au presence. FTIR data of CO adsorbed showed that Ag and Au suppress the CO adsorption in poli-coordination relative to the linear CO. Ag or Au on the Ni surface presents a determinant role in the block of graphitic carbon formation in the reaction of steam reforming of CH4. The fit of Arrhenius equation to rate of the total reaction showed a compensation effect between the apparent activation energy (Ea ap) and logarithmic of prefactor (k0). The linear increase of Ea ap with rise of lnk0 is observed increasing Ag and Au loading, which is followed by decreasing of the catalytic activity. Theses results suggest that the CHx intermediates, formed in the determinant stage of global velocity, show low interaction of with surface of Ni. The increase of the resistance for graphite formation by presence of Ag or Au is mainly attributed to the block of highly uncoordinated Ni atoms, which are higher activity to activation of CH4 and act as nucleation site for graphite formation.
Estudo da reação de formação do pigmento cerâmico azul (V-ZrSiO4) a partir de SiO2, ZrO2 e V2O5
(Universidade Federal de São Carlos, 2005-04-08)
Cabrelon, Marcelo Dezena
;
Boschi, Anselmo Ortega
;
https://lattes.cnpq.br/3259846931278607
;
https://lattes.cnpq.br/1705435326010511
The present work aimed to study the process of synthesis of one of the most important ceramic pigments manufactured by the traditional method of oxide mixture: the turquoise blue of vanadium doped zircon. The plan proposed to this work was subdivided in four stages with own and complementary objectives to the general objective of the work, which is to identify the role played by the main involved variable in the reaction of synthesis of the pigment in question. Considering that, the reaction of synthesis of blue pigment V-ZrSiO4 consists basically on the synthesis of the ZrSiO4 from SiO2 and ZrO2, Part I studied the effect of the characteristics of raw materials, the method and conditions of mixture and the conditions of calcinations on the reaction of synthesis of zirconium silicate, witch indicated that the mixture method acts in decisive way in the process in solid state of zircon formation. Part II correlated the effect of the amount of inserted doped in crystalline lattice and its influence in the strong color capacity of obtained products, as well as its stability in aggressive glass ways, that showed to the saturation of the crystal host from 7% of used, beyond the slightly harmful influence of the time and temperature of burning in the observed final color. Parts III and IV aimed to study the viability of using the tools of statistical planning of experiment, in the studied of the variable using traditional analysis in part I e II. The results indicated a total correlation between the methodologies, in which the statistical tools generated results with bigger load of information with minimum number of experiments.
Utilização de modelos moleculares no ensino de estequiometria para alunos do ensino médio
(Universidade Federal de São Carlos, 2005-04-11)
Migliato Filho, José Roberto
;
Ferreira, Luiz Henrique
;
https://lattes.cnpq.br/4819009378941531
The lack instructional materials for science teaching is a common problem in Brazil, and concerning to chemistry teaching in particular this problem can be observed even in more developed countries. Although molecular models are one of the few materials available for chemistry teaching, they have been hardly used, and this application has been restricted to lessons related to molecular geometry. The lack of materials has specially interfered with stoichiometry teaching, inasmuch as many authors have pointed out that it is one of the most difficult topics for students to understand. This works describes different exercises which were carried out in stoichiometry short courses by using the molecular models as a major teaching resource. These courses were provided for secondary school students in the laboratories of the DQ/UFSCar as well as in two public schools in the city of São Carlos São Paulo, one in a suburb and one in the city center. To collect data, the exercises were performed so that students could use the molecular models. The results showed that such material facilitated the learning process involved in completing exercises related to balancing chemical equations, Lavoisier Law, Proust Law, molar volume, and performance of chemical reactions. It was also verified that the students became independent of simulations with the material during the first exercises at once, and concerning more complex problem, they were almost completely independent. According to the students the use of molecular models made it much easier for them to understand the topics of the short courses. It thus supports researches suggesting that teaching methodologies should prioritize the introduction of new concepts without including mathematical aspects as means of avoiding difficulties in learning chemistry, which are so common in Brazilian Secondary Schools.
A especificação da ação afirmativa no Brasil: a experiência do centro nacional de cidadania negra em Uberaba - MG
(Universidade Federal de São Carlos, 2005-04-11)
Aguiar, Márcio Mucedula
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Silvério, Valter Roberto
This term paper aims to analyse the policies against discrimination and racism of the Black Citizenship National Centre, in Uberaba, State of Minas Gerais. We firmly believe that the incorporation of the myth of racial democracy and its logical ambiguity is directly related to the strategic action against racial inequality developed by this Institute. Such ambiguity can be seen from its conception of Affirmative Actions which combines specific measures for the Black and global measures for everybody, no matter their financial situation or their ethnic-racial identity. This study found out that The Black Citizenship National Centre was born and developed under the strong influence of Black´s movements and claims held at the beginning of the last century as well as their present demands. Besides that, its ambiguous perception of the racial inequalities enables the emergence of allied people from different races and financial situation who could be vital for the construction of an effective racial democracy in Brazil.
Chironomidae (Diptera) em córregos de baixa ordem em áreas florestadas do estado de São Paulo, Brasil
(Universidade Federal de São Carlos, 2005-04-12)
Roque, Fábio de Oliveira
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Strixino, Susana Trivinho
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https://lattes.cnpq.br/1804083229761186
With the aim of understanding the distribution of Chironomidae (Diptera) in Brazilian Atlantic Forest streams at multiple spatial scales, we carried out three complementary studies, which are presented here as chapters: 1) we focus on Chironomidae species richness; 2) we assess the Chironomidae larvae distribution attempting to explore some aspects that could be most influential in determining the chironomid spatial distribution; 3) we report the occurrence of chironomid larvae in fallen-fruits in Atlantic Forest streams. We selected 5 sites in the State of São Paulo and we designed a stratified sampling design incorporating environmental characteristics that potentially may influence chironomid distribution in the different scales (variation among sites streams mesohabitats). We used different sampling methods for collecting larvae, exuviae and adults of Chironomidae. As a whole, our results allow us to point out: 1) low order streams from Atlantic Forest as one of the most chironomid speciose areas in the world; 2) the chironomid assemblage is taxonomically deep, with some genera being represented by a large number of species (Tanytarsus, Caladomyia, Polypedilum, and Stenochironomus); 3) the identification of the scale importance depends on the chironomid assemblage descriptor and the taxonomic resolution considered; 4) studies focusing on one scale or habitat (e.g. riffles) are not appropriate for studying Chironomidae distribution patterns and richness in low order streams; 5) biological traits of some groups may underlie most evident in-stream chironomid distribution pattern; 5) the input of allochthonous matter from riparian vegetation, particularly fallen-fruits, represents an important habitat and food resource for chironomids in Atlantic Forest streams.
Movimento negro no cenário brasileiro: embates e contribuições à política educacional nas décadas de 1980-1990
(Universidade Federal de São Carlos, 2005-04-12)
Rodrigues, Tatiane Cosentino
;
Silvério, Valter Roberto