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Efeitos de um programa de habilidades sociais comunicativas para crianças com distúrbio específico de linguagem
(Universidade Federal de São Carlos, 2012-08-10)
Carlino, Fabiana Cristina
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Costa, Maria da Piedade Resende da
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https://lattes.cnpq.br/0708927614828521
The language is considered the first form of socialization of the child, and, in most cases, is done explicitly by parents through verbal instructions during daily activities. Thus, the child has access, even before learning to speak, the values, beliefs and rules, by contacting the concepts of their culture. However, some children experience serious difficulties in the acquisition and development of it. The Specific Language Impairment (SLI) is a change that has piqued the interest of many researchers due to its particularity, which refers to the great difficulty in developing language skills in the absence of auditory impairments, motor, mental retardation, neurological damage, comprehensive developmental disorders, acquired brain insults, restricted social interaction, behavioral disturbances, and emotional significance. The present study aimed to: a) assess the effects of an HSC program for a group of children with Specific Language Impairment (SLI), b) analyze the performance of each participant in this program, as indicators obtained preoperatively and post-intervention and c) to verify positive change reliable components Communicative Social Skills group and individually. Participants were eight children, between seven and nine years and eleven months of chronological age, both genders, with SLI. Data collection was divided into five phases: Preliminary - Contact those responsible; Phase I - Evaluation pre-intervention; Phase II - Planning and implementation of the intervention program; Phase III - Evaluation postintervention; Phase IV - Guidance and evaluating judges. Statistical analysis was based on the JT method, which aims to evaluate the pre-and post-intervention participants as a group and individually. The results suggested: reliable positive changes in the components of verbal and nonverbal content, but not reliably positive change was observed in verbal form. As the evaluation of the family QAP, P1, P2, P6 and P7 were participants more positively evaluated. While the evaluation of DC, the best participants were evaluated P3, P4, P5 and P8. It discusses the contributions of the study in terms of knowledge produced from steps taken, decisions and challenges of research and the 6 importance of investment in research in the area, involving the construction, adaptation and improvement of assessment tools for HSC DEL.
O problema de Cauchy para sistemas quase-lineares hiperbólicos é bem posto em espaços de Hölder
(Universidade Federal de São Carlos, 2012-08-10)
Silva, Rômel da Rosa da
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Santos Filho, José Ruidival Soares dos
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https://lattes.cnpq.br/6112529384454347
;
https://lattes.cnpq.br/3804309368611422
We consider the Cauchy problem for the quasi-linear systems that is, the system is hyperbolic at u = 0. We show that certain Besov spaces are preserved by flow of the solution, near the null solution.
Produção de etanol e hidrolisado protéico da casca de soja
(Universidade Federal de São Carlos, 2012-08-10)
Rojas, Mayerlenis Jiménez
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Giordano, Raquel de Lima Camargo
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https://lattes.cnpq.br/2812374302014326
Soybean hull is a lignocellulosic biomass that contains 38-51% of cellulose, which could be converted to ethanol. In addition, contains 9-14% of protein that can be hydrolyzed by endoproteases, releasing oligopeptides with nutritional applications. Although glycoside and peptide linkages can be hydrolyzed by acids, the cellulose molecules are more resistant than the protein and hemicellulose molecules. In this way, the acid treatment of the biomass would reduce its hemicellulose content, and the remnant cellulose into solid fraction would be more susceptible to hydrolytic enzymes. In this work, different routes of protein, hemicellulose, and lignin solubilization were evaluated, intending to obtain ethanol and soluble oligopeptides from the soybean hull. The protein was recovered as oligopeptides by hydrolysis of the lignocellulosic biomass using the commercial endoprotease Novo-Pro DR at 60oC, pH 9.0, 5 h, and different enzyme concentrations (1, 2, and 4%, m/m). A sequential hydrolysis using chymotrypsin and Novo-Pro DR, both at 1% (m/m) enzyme concentration, was also evaluated. The results showed that hydrolysis with 1% Novo-Pro DR allowed solubilization of 56.9% of protein from the soybean hulls. Nonetheless, at same temperature and pH, in absence of enzyme, was possible to solubilized 45.6% of the proteins. This solubilization is probably due to liberation of the physically aggregated units. The increase of endoprotease concentration from 1 to 2% increased the protein removal to 74%. However, the increase from 2 to 4% not increased significantly the protein solubilization. The use of chymotrypsin, an enzyme with high specificity and that work at mild conditions, allowed a solubilization of 44% protein. Nonetheless, the removal of lignin using chymotrypsin was higher than that using Novo-Pro DR. When in-nature soybean hull was hydrolyzed by acid or protease (1% Novo-Pro DR) followed by acid, the protein removal was around of 90%. The lignocellulosic biomass was hydrolyzed with 3% (v/v) H2SO4, solid:liquid ratio of 1:4, 120oC, and 20 min. 20 min. Carbohydrate analyses showed that the acid treatment allowed to hemicellulose removal around of 46.7% in the xylose form. The protein content of the soybean hull was almost totally solubilized during the acid hydrolysis, without significant loss of cellulose. On the contrary, large cellulose loss was observed during the acid hydrolysis of in-nature soybean hull. In this way, if it is intended to produce a protein hydrolysate containing controlled composition or ethanol from remnant solid fraction, is strongly recommended the previous enzymatic solubilization of the proteins. The chemical composition of the solid biomass after sequential hydrolyses with protease and acid showed cellulose content around of 49% for all samples. So, the biomass treated with 1% (m/m) Novo-Pro DR was saccharified with Acellerase 1500 at 50oC, pH 4.8, and enzyme/substrate ratio of 7 FPU/g of cellulose for 72 h. Under the same conditions, soybean hull in-nature, pretreated with acid, and pretreated with protease were submitted to cellulolytic hydrolyses. The cellulose-to-glucose conversion was around of 40% for the last two biomass. The increase of the enzymatic load to 20 FPU/g of cellulose allowed a cellulose conversion of 55% for biomass pretreated with 1% (m/m) Novo-Pro DR, followed by acid hydrolysis. The supplementation of the Acellarase 1500 with 120 IU of β-glucosidase and 1% (m/m) of pectinase not produced any increased in the cellulose conversion. The biomass was pretreated by organossolv method (50% ethanol, 170oC, and 1h) and saccharified with Acellerase 1500 under the same conditions described above. This procedure yielded a cellulose conversion of 52%, with less removal of hemicellulose. This result showed that lignin was causing greater steric hindrances to the enzymatic attack. The biomass pretreated with acid and with protease (1% Novo-Pro D) followed by acid yielded the same glucose-toethanol conversion, reaching an ethanol concentration around of 13 g/L.
Sistemas agroflorestais na recuperação de áreas de preservação permanente
(Universidade Federal de São Carlos, 2012-08-10)
Machado, Fábio José
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Stolf, Rubismar
This essay aims at evaluating the use of alternative reforestation models in order to recover degraded areas in permanent preservation areas. The potential of effective recovery was analyzed regarding sustainability indicators which were applied according to the principles of the MESMIS tool. Comparing a forest fragment (AT), a handled agroforestry system (SAF), two recovery areas and a pasture area. All of the analyzed places belong to strategic regions considering the biodiversity conservation as well as water resources, as they are located in different environmentally protected zones (APA s), which provide water for the Cantareira System (Sistema Cantareira). The analysis took place in the recommended period for the monitor in the RAD projects, in the first three years in order to evaluate the current situation and also intervene in the maintenance if necessary. The sustainability indicators choice was based on the easy applicability and facts interpretation, which belongs to three groups: man-induced disturbance, composition and ecological function. The maninduced disturbance revealed that there was evidence of disturbance in all the places. In the composition indicators, the forestry fragment (AT) showed the higher value considering the biodiversity index. However the difference was not really significant if compared to the handled SAF. In the implementation of ecological function indicators, the SAF showed the highest rate of tree canopy. So, it was determined that the agroforestry system shows good results considering the diversity when it is handled. In addition to that, it showed big viii potential in recovering degraded areas and in enrichment of forest fragments that can be handled for a longer period than the one estimated by law.
Estimativa de energia no infinito para equações hiperbólicas com coeficientes oscilantes
(Universidade Federal de São Carlos, 2012-08-10)
Zapata, Miguel Angel Cuayla
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Santos Filho, José Ruidival Soares dos
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https://lattes.cnpq.br/6112529384454347
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https://lattes.cnpq.br/2404733136036136
We study the behavior, as t ∞, of the energy for the solutions of the Cauchy problem for some strictly hyperbolic linear second order equations with coeficients very rapidly oscillating.
Vulnerabilidade das comunidades pesqueiras de São Tomé e Príncipe face às mudanças climáticas
(Universidade Federal de São Carlos, 2012-08-10)
Fernandes, Ilunilson dos Santos Paquete
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Valêncio, Norma Felicidade Lopes da Silva
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https://lattes.cnpq.br/7161606146208875
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https://lattes.cnpq.br/1659424824376207
With the release of the report of the Intergovernmental Panel on Climate Change (IPCC) in 2007, the certainty that critical events related to climate change directly and indirectly affect human activities has emerged. The report confirmed that the least developed countries (LDCs), particularly those located in Africa, are the most vulnerable to the effects of climate change. These vulnerabilities result from multiple factors that influence the manner in which people adapt to local biophysical and social impacts of climate variability. Therefore, this research aims to generally develop, describe and analyze, through qualitative procedures of sociological research, social representations that the traditional fishing communities on the island of Sao Tome and Principe, Africa have over critical events, which in design, refer to climate change and how such representations affect their organization and spatial distribution practices. To achieve the objective of this research, we adopted methodological procedures of qualitative basis such as: state of art review, and preliminary documentary to field research, the latter being accomplished through the use of focus group technique and interviews. The research problem is linked to some peculiarities of African context where the island goes through many socioenvironmental hardships and limitations, which demonstrate the relevance of this undertaken research.
As práticas de letramento da família e as dificuldades de aprendizagem: perspectivas para o debate
(Universidade Federal de São Carlos, 2012-08-12)
Oliveira, Patricia de
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Lacerda, Cristina Broglia Feitosa de
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LACERDA, C. B. F. de
The object of this research were qualitative ethnomethodological approach to the literacy practices of parents of children with learning difficulties in order to understand what values and beliefs could be underlying their practices and literacy events that give children. Literacy can be understood as the ability to handle different bearers text, making social uses of written language. During the development process to literacy skills, the way the family makes use of written language can be crucial to a child who is building his own literacy process, leading her to succeed or difficulties in school learning. This research involved the participation of parents of children with learning difficulties in a public school in a small city in the interior of Sao Paulo .. To collect the data were organized 10 meetings, being 1 per week, lasting approximately 1 hour and 30 minutes. At these meetings, the researcher read children's stories and perspectives presented for participants to read to their children at home. The participants reported their experiences with written language and how was the way that promoted literacy events for their children. The meetings were recorded in audiovisual and transcribed for analysis. The analyzes showed 3 categories for study: the literacy events that participants experienced in their childhood, their literacy practices, and literacy events that lead to their children. The data showed that families has been providing their children with literacy events consonants needs and beliefs and making use of accessible technologies of information and communication, allowing the children to enter a world of letters corresponding to these needs and beliefs, but so other conventional forms of reading and writing.
Por um conhecimento sincero no mundo falso: Teoria Crítica, pesquisa social empírica e The Authoritarian Personality
(Universidade Federal de São Carlos, 2012-08-13)
Antunes, Deborah Christina
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Maar, Wolfgang Leo
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https://lattes.cnpq.br/8746615407370574
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https://lattes.cnpq.br/1065956470701739
The present PhD dissertation discusses the relationship between the Critical Theory of Society and empirical social research as elaborated in the work of the Institute of Social Research of Frankfurt, particularly after 1931, during the period in which it was under the direction of Max Horkheimer. Thus, it investigates to what extent such a nexus considered part of this theory s immanent coherence can be found in the research carried out in the United States and published as The Authoritarian Personality. The first chapter is dedicated to the reconstruction of Horkheimer s notion of interdisciplinary materialism. The discussion is based on his inaugural lecture as the Institute director, and on his essays published during the 1930s. In the second chapter, the main empirical social research projects carried out by the Institute members, in Germany and in the United States, are presented. The third chapter is dedicated to Theodor W. Adorno, his critique of Sociology and his views about the accomplishment of empirical research in the scope of Critical Theory. The last chapter is dedicated to an analysis of The Authoritarian Personality, seeking connections between the theory and procedures and instruments, and also between theoretical elaborations on their results.
Características, fatores críticos e indicadores de agilidade no gerenciamento de projetos de produtos inovadores
(Universidade Federal de São Carlos, 2012-08-13)
Almeida, Luís Fernando Magnanini de
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Silva, Sérgio Luis da
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https://lattes.cnpq.br/4164265591178698
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https://lattes.cnpq.br/9522305814931992
The theory of project management presents difficulties when applied to the development of innovative products. To solve these difficulties, a series of management methods were created. These methods receive the nomenclature of agile project management and increase the agility of the management process which would be a strategy to deal with the difficulties in those particular projects. However, the concept of agility is vague in the project management theory and the studies found that attempts to measure this performance was not satisfactory, presenting too much subjectivity in the definitions of constructs and starting from little robust definitions of agility. To try to solve this problem, a new model for agility in project management was proposed by Conforto (2011), relying on a definition coined from a systematic literature review of several areas that exhibit this same concept, and perform another systematic review on the models to measure agility in order to incorporate their strengths and create solutions to major weaknesses. This study aims to examine the relationships between the dimensions present in this model of agility to manage projects, in order to verify its validity and possibility its future use as a basis for measurement. Thus, the observed relationships between some features arising from the use of practices from the theory of agile project management theory, critical factors that may impact on the performance of the practices and indicators of agility. For this, a survey was made at the members from eight communities in Brazil Linkedin® chosen from among 79 candidates and selected according to 7 criteria. Also, was created the theoretical concept of "profile 500" which can be used in future research with have analysis made between members of this social network. There was obtained 172 valid responses from 966 users considered eligible for the study. Correlation analysis showed that the relationships proposed in the model of Conforto (2011) are valid and that agility is related to the presence of certain characteristics and are not inherent to the management method chosen, but this performance is related to customer participation and time taken decision. Finally, there was evidenced the importance of customer participation in the design and validation of partial results for a faster management process, and the necessity of carrying out the planning, development and validation with the participation of the client to perform better agility.
Durabilidade mecânica de compósitos de polipropileno com reforço híbrido de fibra de coco e talco
(Universidade Federal de São Carlos, 2012-08-13)
Antunes, Marcela Caroline
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Sousa, José Alexandrino de
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https://lattes.cnpq.br/7737833809468759
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https://lattes.cnpq.br/3480730374217911
The use of natural fibers, as possible alternative reinforcement for synthetic fibers such as glass fibers, in polymer composites meets the requirement for development of new materials with environmentally sustainable technology. Such composites are especially attractive for engineering applications, such as in automobile industry, as these new materials can meet the requirements for adequate mechanical performance whilst exploiting the low density of natural fibers. As the mechanical fatigue durability is of fundamental importance in this area, the main objective of this work is to study the mechanical fatigue properties of polypropylene homopolymer (PP) composites with hybrid reinforcement of coconut fiber (CoF) and mineral filler talc (T), used to obtain a better balance between mechanical properties and lower density. Thus, PP composites with hybrid FCo/T reinforcement and compatibilized with maleated PP (PP-g-MAH) were prepared by twin-screw extrusion at various concentrations and test specimens injection molded for short-term mechanical properties characterization (tensile, flexural, impact and DMTA tests). The PP hybrid composite with the best balance of mechanical properties of stiffness, strength and reduced density was formulated with 30%FCo, 20%T and 3%PPg- MAH (wt %). This hybrid composite, along with its references composites with only FCo (30%) and only talc (20%), besides unmodified PP, were all submitted to fatigue testing carried out under cyclic sinusoidal tensile loading in tension controlled mode (frequency: 3 and 6 Hz and R = 0.1). The experimental results showed that all composites, both hybrid and reference composites, presented higher number of cycles to failure in comparison to the matrix PP polymer, probably due to reduction of mechanical hysteresis with increased content of reinforcement. However, extrapolation of the S-N fatigue curves indicates that all analyzed composites would present a fatigue resistance lower than the endurance limit observed for the unmodified PP polymer.
Sistematização do cálculo e verificação de sistemas estruturais de galpões pré-fabricados de concreto
(Universidade Federal de São Carlos, 2012-08-14)
Rodrigues, Camila
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Carvalho, Roberto Chust
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https://lattes.cnpq.br/3633394168236221
This research is the systematization of the calculation and verification of a type of a very typical structural system of precast concrete in Brazil: the sheds. Through this research it is showed the main structural systems for this type of construction currently in use in Brazil. It also describes the component elements of these systems detailing the design techniques. Following it is a detailed the considerations of the actions over them and how to calculate the strain and displacement. With all previous data collected it is shown how the design is made with reinforcement of the roof s beam and how to guarantee that it meets with the relevant Brazilian standards. In the sequence, examples are made so that the reader can consolidate all the concepts involved in the previous sections. It shows the calculation and verification and finally points out the possibilities of improvement in some systems, detailing it. Finally, it highlights the points can still be studied to improve the design and the knowledge of sheds precast concrete.
Desafios para a transição agroecológica no arco de desmatamento da Amazônia : estudo de caso no assentamento entre Rios - MT
(Universidade Federal de São Carlos, 2012-08-14)
Alvares, Suzana Marques Rodrigues
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Ferraz, José Maria Gusman
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https://lattes.cnpq.br/3851804858390996
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https://lattes.cnpq.br/0722384791788183
There is a critical situation for settlements, in terms of land reform, that can be seen by the great number of people abandoning their lands in the big areas with deforest and bonfire in Amazon. The present dissertation intended to analyze the Agroecological Transition Process in Entre Rios Settlement which was driven forward by PADEQ Sustainable Entre Rios project in an agroecological perspective. It was used the participatory approach through analyzes of the sustainability indicators for agro ecosystems. The Participatory Rural Appraisal evidenced that the main source of income of the settlers is still wood and that most of the settlers who remain in Entre Rios make their living through external sources of income, such as retirement, rent of property in other areas, Bolsa Família. It is also common to find families where men have to do temporary jobs in near farms or in saw mills to complete the family income, as well as to invest in their own animal husbandry activities. The results is that most settlers abandon their land lots for lack of proper conditions, as an example, in the first semester of 2010, 3 families left the settlement in one of the settlement areas. The Cupuaçu family presented the best index of total sustainability ( SITotal = 2.09 ), owing to the diversity of activities allowing income generations, inside or outside the ranch, besides the intense involvement of the family with the Association, courses and exchange, contributed to this result. Considering the ecological sustainability, the availability of alternative productions practices, especially, apiculture, and agroforestry systems, were fundamental factors for the composition of higher indices. The Social sustainability indices have presented the worst performance among all indices, for every family, showing the lack of structure and the present abandonment situation that the settlers are exposed to. Besides the blocks in the production process, there is still the difficulty to access consumer markets, due to the distance and lack of transportation for the products. The results indicated that the settlement participation is vital to build projects that attend to their concrete needs and particularities. This participation can increase the adhesion in numbers and helps them to understand better their management process and development. It is necessary some actions in order to develop the diversified production food and not forest wooden products in ecological bases taking all productive environment. It seems important some actions in the agroecological transition process to guarantee the sustainability and improvement of the settlement lives quality. It will help to maintain the settlement people in their lands. The governmental institutions constraints and the gap of help jeopardize the settlement situation as a result there is an increasing in the region deforest and bonfire.
Contribuição para o emprego de portas modulares em projetos de alvenaria estrutural
(Universidade Federal de São Carlos, 2012-08-15)
Grabarz, Regina Candeloro
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Parsekian, Guilherme Aris
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https://lattes.cnpq.br/7798651726059215
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https://lattes.cnpq.br/3026155515104619
The construction industry often related to high handwork production processes, which results in waste of physical and financial resources. The current great demand for new buildings leads to the need of industrialized elements, components and technologies in order to push the evolution of the construction process. In view of these aspects, modular coordination stands out as an excellent strategic tool since it aims to organize the dimensions of buildings, in order to reduce the variety of sizes in which the elements and components are produced, allowing its ready installation without the need of any modification. The structural masonry stands out in this direction since its design is guided by modular coordination, allowing the application of this concept and thereby to rationalize the subsystems of larger impact of the building: the partitions and the building structure. However, although this system contributes to the modular coordination, other construction components and elements must also have modular measures, being the element door an example. With that in mind, this research seeks to contribute to the dimensional standardization of "opening doors with one leaf" through the diagnosis of modular dimensions suitable for structural masonry designs. Initially, it was diagnosed the possible modular dimensions for the door space. The analyses resulted in the possible horizontal space before de door installation of widths with final 1 (61, 71, 81, cm) and 6 (66, 76, 86, cm). The vertical modular space is equal to 221 cm before any other construction element is added and 217 cm considering a regularization capping and floor tile over the slab (nominal). The width of wood door leaf is currently commercialized with dimensions ending with 0 (60, 70, 80, cm) and 2 (62, 72, 82, cm). These dimensions were diagnosed suitable to modular masonry design when combined with door post thickness of 2 and 2,5 cm respectively. However the 210 cm height, available in the market, proved to be inadequate. With this dimension a construction solution is need to fill the gap between the door and masonry, which is not wanted and becoming very undesirable today. The study leaded to the conclusion that a door leaf height of 212,5 cm would be ideal. Also, although it is possible wood-doors of 0 and 2 endings widths (current standard) changing the standards to width with endings dimensions of 3 (63, 73, 83, ... cm) and 8 (68, 78, 88, cm) would make possible to have the same width standard for door leafs of several materials (wood, metal). The metal doors of steel and aluminum are available in the market in several different. Although most of them are suitable for the modular dimensions the proposals are made here to standardize and reduce the number of different dimensions. The first one has lower impact, just recommends to eliminated some of the marketed dimensions standardizing to width endings with 1 (61, 71, 81, cm) and in height 211 cm. The other suggestion has higher impact, but allows the same dimensions for doors of different materials, thus having only one dimension standard for door leafs regardless of its material.
Agricultura urbana em Rio Claro (SP): produção e políticas públicas
(Universidade Federal de São Carlos, 2012-08-15)
Leme, Marina Koketsu
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Pimentel, Andréa Eloisa Bueno
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https://lattes.cnpq.br/1927569399091860
The importance of Urban Agriculture (UA) has been increasingly recognized in recent years. It emerges as an important survival strategy, especially for the poorest population who can consume and sell the food produced. It also has other advantages such as occupation of empty spaces, maintenance of green areas and the producers' increase of their self-esteem. But the practice also has certain barriers that require care, as the misuse of pesticides, the possibility of food contamination by water or land, theft of crops and other risks. The municipality of Rio Claro (SP), the object of the present study, is an example of a city that has several types of UA initiatives, however there is still no specific legislation directed to the sector. Thus, we sought to conduct an analysis of these urban gardens in the city considering the optical output and public policies. The field research included observations and interviews, using semistructured questionnaire applied to farmers responsible for the gardens. From the analysis of the results it's noted that the gardens in Rio Claro are still few, occupying a small area. Despite the difficulties, the UA provided, in general, an improvement in the respondents' quality of life. Moreover, the practice of UA has great potential for expansion and could be better exploited in the city. Thus some actions are required by the municipality to encourage urban agriculture in the city, extending its benefits and reducing its drawbacks.
Diagnóstico dos agroecossistemas na microbacia hidrográfica do rio Pirapora - município de Piedade/SP
(Universidade Federal de São Carlos, 2012-08-16)
Schneider, Fernando
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Costa, Manoel Baltasar Baptista da
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https://lattes.cnpq.br/4748534388515487
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https://lattes.cnpq.br/0220281286346217
The present work was aimed at making the diagnosis of 25 Agroecosystems located in the Pirapora river micro basin, in the Piedade municipality, State of São Paulo, focusing particularly on the adopted management practices. The socioeconomic, productive and environmental implications of these practices were analyzed and contextualized in the scenario of São Paulo State agriculture. The focus in the watershed, besides their legal aspects, reflects its importance as a geographical until priority actions for integrated management, conservation and natural resource management. In this study we sought to define the indicators that reflect the complexity of management were studied based on the method proposed by MESMIS, as well as by systematic methodological experience Agronomic Institute of Paraná IAPAR, systemic approach. The main results arising from systematized this work were: a significant presence of family farmers in the region, the incompatibility of management techniques adopted in Agroecosystems in relation to environmental and soil characteristics of the region, the weakness in the organization among the farmers, the narrow market for the sale restricted to the middleman, the heavy dependence on external inputs to the system resulting from a conventional farming, the use of pesticides banned, the impairment of water resources and public health of residents for limited use in the preservation of water sources and lack of sanitation. These factors indicate that the diagnosed type of agriculture currently practiced in the region is undermining the sustainability of Agroecosystems due to the degradation of natural resources and, consequently, of their own agricultural activities in the watershed.
Caracterização da produção e avaliação de indicadores de qualidade tecnológica de amostras de melado do estado de São Paulo
(Universidade Federal de São Carlos, 2012-08-16)
Silva, Mariane Martins Pereira da
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Borges, Maria Teresa Mendes Ribeiro
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https://lattes.cnpq.br/1800048119205212
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https://lattes.cnpq.br/1083005939009933
The molasses, a syrup made from the juice of sugarcane juice, is a sweet liquid, nutritious, homemade and very popular in the Northeast Region of Brazil. It is few explored by small farmers in São Paulo State and, because this, the present study aimed to identify how is the professional involved in its production at São Paulo State through a questionnaire. Whit the returns obtained from the questionnaires and the results of physicochemical analyzes, it can be concluded that few producers know the best way to produce molasses. It s necessary instruction and training for these to be able to exploit this market share.
Avaliação de modelos de sinterização por fluxo viscoso e determinação da taxa de crescimento de cristais e fração cristalizada em vidros
(Universidade Federal de São Carlos, 2012-08-16)
Reis, Raphael Midea Cuccovia Vasconcelos
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Zanotto, Edgar Dutra
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https://lattes.cnpq.br/1055167132036400
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https://lattes.cnpq.br/9034852268717585
Glass-ceramics are materials obtained from the controlled crystallization of glass. The properties of these materials are controlled by the nature and proportions of the crystalline phases and residual glass present. Sintering with concurrent crystallization of glass powders is one of the routes for the development of these materials. One of the few models that describe sinter-crystallization is the Clusters model, which allows one to calculate the density of sintered compacts by knowing composition-dependent properties, such as viscosity (η), crystal growth rate (U) and surface tension (γ), and process-dependent parameters, such as particle size distribution and the density of surface nucleation sites (NS). The determination of input parameters for the model can be labor-intensive, which may difficult its use. In this work a critical assessment of the Clusters model and its bases was performed by checking its predictions against results of sintering of spherical and jagged diopside glass particles. Frenkel s model was capable of describing the initial stages of sintering only qualitatively, requiring an adjusting factor of ~1/3. With this correction, the Modified Clusters model described the powder densification in different conditions well. The effect of crystallization was slightly underestimated by the model, which could be explained by a mechanism of Ns increase in the pores surfaces as observed in a previous work. It has been demonstrated that the jagged particles increasingly round during the heat treatment causing the densification rate to gradually approximate that of spherical particles. Additionally, a model for the determination of crystallized fraction from the surface of particles was derived and can be applied for sintered particles or crystallization DSC studies. A new technique capable of the determination of the crystal growth rate in a temperature range using a single DSC run was developed and successfully tested for three different glasses.
Ondas de spin em paredes de domínio unidimensionais em monocamadas magnéticas
(Universidade Federal de São Carlos, 2012-08-16)
Caprara, Leandro Peres
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Farinas, Paulo Eduardo Fornasari
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https://lattes.cnpq.br/0309157540839329
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https://lattes.cnpq.br/7222840232739649
Recent investigations on ferromagnetic monolayers predict the existence of spinwave modes without gap in the spectrum, even in the presence of anisotropy. These excitations propagate within the domain walls that exist in the monolayer, hence in quasione- dimensional structures. They are different from the known bulk-modes whose spectrum presents anisotropy gap and whose propagation may cover all the monolayer's extension. Moreover, since they do not have gap in the spectrum, the predicted modes are not associated to an activation temperature and must influence low-temperature observable physical properties. In the present work, a theoretical study is presented for a single ferromagnetic monolayer with domain walls and the response toan oscillating magnetic field. Gapless spin-wave modes' resonances are studied in the results.
Determinação de molibdênio em plantas combinando microextração e espectrometria de absorção atômica em chama
(Universidade Federal de São Carlos, 2012-08-16)
Villamizar, Jenny Andrea Oviedo
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Nóbrega, Joaquim de Araújo
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https://lattes.cnpq.br/8833989058164529
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https://lattes.cnpq.br/5005205399281843
In this study, a procedure for the determination of low concentrations of molybdenum in plants by flame atomic absorption spectrometry (FAAS) was developed. The poor sensitivity of FAAS for determination of refractory elements such as molybdenum, and the typical low levels of this micronutrient in plants require the use of a preliminary preconcentration step. The procedure was based on the solidified floating organic drop microextraction strategy (SFODME). This method was selected based on its simplicity, high enrichment factors and low consumption of organic solvents. Because of SFODME microvolume characteristics, the effect of the discrete introduction of samples in FAAS was studied. The following extraction parameters were evaluated: type and concentration of complexing agent, type of solvent, solvent volume, use of ultrasound or vortex in the extraction process, and effect of discrete nebulization. All parameters were evaluated considering their effects on sensitivity for the determination of molybdenum in plant samples by FAAS. The most critical effects were caused by the type of complexing agent, the use of vortex mixing and discrete nebulization. Prior to the microextraction procedure, Mo complexing conditions were optimized. A 0.5% m v-1 8- hydroxyquinoline solution at pH 4.75 adjusted with acetate buffer and complexing time of 10 min were the ideal experimental conditions. For the microextraction procedure, the highest enhancement factor for Mo was obtained with 60 μL of 1-undecanol and using the vortex mixer for 2 min. Appreciable sensitivity improvements were observed by combining microextraction, the introduction of discrete volumes of sample, and determination of Mo by FAAS. An enrichment factor of 67, limit of detection of 4.9 μg L-1 and limit of quantification of 16.4 μg L-1 were reached. The accuracy of the developed procedure was demonstrated by determining Mo in certified reference materials. Finally, the procedure was applied to samples of roots and leaves of corn.
Estudo do processo de soldagem por fricção por ponto da liga de magnésio AZ31
(Universidade Federal de São Carlos, 2012-08-17)
Campanelli, Leonardo Contri
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Alcântara, Nelson Guedes de
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https://lattes.cnpq.br/3123107570992184
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https://lattes.cnpq.br/8983259236829248
The great potential of magnesium alloys on reducing structural weight and therefore contributing with energy efficiency of transportation facilities has mainly attracted the automotive and aeronautic industries. The difficulty of joining such materials is one of the biggest challenges to overcome, expanding opportunities for solid state welding technologies. This work was carried out to study the feasibility of joining AZ31 magnesium alloy by friction spot welding (FSpW) process. The purpose was to evaluate the influence of the process parameters on microstructure and mechanical properties of the welded joints, as well as to comprehend the fracture behaviors of the welds under shear loading and to optimize the welding process. The joints were produced in overlap configuration through different combinations of parameters, which were established by statistical methods for design of experiments, and later submitted to mechanical and metallurgical characterization. For assessing the failure mechanisms, modeling and simulation of stress distribution around the weld during lap shear test were performed. The results confirmed the possibility of joining AZ31 alloy through FSpW, as well as the superiority when compared to friction stir spot welding (FSSW) process. Although the change on the tool profile had shown a significant effect over the process parameters and weld strength, the maximum load values demonstrated the robustness of the welding process. Microstructural regions exhibited an enhanced level of uniformity, with the exception of recrystallized zone. Mechanical behavior presented a strong dependence on metallurgical features arising from the flow of plasticized material, which were identified as bonding lines and hook, as well as the condition of material stirring. The flexural loading associated to the inaccurate alignment of the welded specimen emerged as an operational variable, also influencing the crack propagation path.