Evaluation via multivariate techniques of scale factor variability in the rietveld method applied to quantitative phase analysis with X ray powder diffraction

ABSTRACT: The present work uses multivariate statistical analysis as a form of establishing the main sources of error in the Quantitative Phase Analysis (QPA) using the Rietveld method. The quantitative determination of crystalline phases using x ray powder diffraction is a complex measurement process whose results are influenced by several factors. Ternary mixtures of Al2O3, MgO and NiO were prepared under controlled conditions and the diffractions were obtained using the Bragg-Brentano geometric arrangement. It was possible to establish four sources of critical variations: the experimental absorption and the scale factor of NiO, which is the phase with the greatest linear absorption coefficient of the ternary mixture; the instrumental characteristics represented by mechanical errors of the goniometer and sample displacement; the other two phases (Al2O3 and MgO); and the temperature and relative humidity of the air in the laboratory. The error sources excessively impair the QPA with the Rietveld method. Therefore it becomes necessary to control them during the measurement procedure.

The Linear Potential Propagator via Wave Function Expansion

ABSTRACT: We evaluate the quantum propagator for the motion of a particle in a linear potential via a recently developped formalism [A.B. Nassar et al., Phys. Rev. E56, 1230, (1997)]. In this formalism, the propagator comes about as a type of expansion of the wave function over the space of the initial velocities.

Modelagem IEEE 1815 DNP3 em VHDL e análise de comunicação SG via IEEE 802.15.4 e IEEE 802.11

Pós-graduação em Engenharia Elétrica - FEIS

Acesso remoto seguro de experimentação em tempo real

Pós-graduação em Engenharia Elétrica - FEIS

Resolução do problema de carregamento e descarregamento de contêineres em terminais portuários via Beam Search

One problem that has been happening frequently in port terminals is the poor planning of the loading and unloading of containers. The reason of this problem is the lack of an efficient method that provides the best means of these operations. The main goal of this work is, to implement a method that provides the best ways to perform the loading and unloading of containers, at each port and thus bring a great saving for these terminals, since the number of moves is directly proportional to cost. To carry out this program was used the idea that the containers are placed in vertical stacks, where the access can be done only by the top of the stack, so the ship was treated as an matrix and to fill it, two rules were created for loading and two for unloading. To obtain the best sequence of rules was used Beam Search method, which is an enumeration type implicit method that analyzes only the best solution of the tree generated. Thus, the program developed in the Java language, provides the best way to perform the loading and unloading ports and the way as the ship leaves each port using a graphical interface

Tratamento da superfície do alumínio via eletrólise a plasma

This paper presents the study on the application of the electrolytic plasma for surface treatment of aluminum. A bibliographical study on the material of interest was preliminarily performed and later designed and built an electrolytic cell, including the excitation source. Unlike conventional electrolysis process, the plasma assisted carry on in the non-linear region of characteristic current/voltage curve. Therefore it requires for the on set of the process that the power supply operates on harder conditions than those on high current process. The plasma produced during the present investigation has temperatures in the range o 6,0.10 3 -7,0 .10 3 K, well above those found in conventional chemical process. It also shows a particular dynamic to promote changes on surface and to produce new materials. The plasma is generated by microdischarge in vapor or gas bubbles involved in physic-chemical processes in electrode regions of the electrolytic cell. The electrode material was the aluminum (7075). The Process Electrolytic Plasma Processing (EPP) is sensitive to various parameters such as operating voltage, current density, electrolyte, concentration of electrolyte, geometry of reactor, temperature of electrolytic solution and dynamic of the fluid in the cell. The experiments were carried on in order to find parameters for a stable abd steady operation. The choice for the electrolytic was silicate/alkali solution in various concentrations to operate in various voltage as well. Plasma was produced on negative (cathode) and positive (anode) electrode, in specific conditions. A stable operation on the cathode process was obtained with low concentration of the electrolytic in aqueous solution, current density around 250V effective voltage. For the evolution of plasma in anodic process it was required higher concentrations and higher... (Complete abstract click electronic access below)

Obtenção e caracterização de compósitos via RTM com alta fração de fibras de carbono processados à temperatura ambiente

After confirming the high specific mechanical properties of composite materials by scientific studies conducted over the last decades, one of the challenges of this new class of materials is the ability to achieve mass production at a more affordable cost, which has become indispensable. The Resin Transfer Molding (RTM) is an excellent method for manufacturing composite materials. Despite being a process widely used by international companies in the production of high performance structural composites, only a short time the national aviation industry has shown interest in implementing this type of processing to more complex structures and greater structural responsibility. In aeronautical projects, the reproducibility and the relative low cost of this process, several studies have been performed in Brazil for learning and perfecting this technique. This process is suitable for producing polymer components both simple as complex geometry, and allows to achieve consistent thickness, with high quality finish and without limiting range. Polymeric composite components for the high mechanical stress applications such as aircraft structures, satellites, etc., require a strict control of volume fractions of the composite constituents, beyond the knowledge of their mechanical and thermal properties. Therefore, in this experimental work degree study on the mechanical, thermal and of porosity composites processed by RTM processed characterization was performed. This characterization was performed targeting a possible aerospace application of this composite material. For the production of composites, process equipment (RTM RTM injector Radius 2100cc) was used. The processed carbono/epoxy composites were characterized via flexure tests mechanically and thermally analysis via DMA, DSC and TGA. To determine the volume fraction of fibers, the composite samples were analyzed via matrix digestion (ASTM D3171) ... (Complete abstract click electronic access below)

Recebimento de dados GNSS via Internet em RTCM 3 e conversão para RINEX utilizando a plataforma J2ME

Changes are occurring worldwide, including the area of positioning using Global Navigation Satellite Systems in mobile devices such as mobile phones or laptops. This is due to the great improvement and availability of Internet services to these mobile devices. The accuracy and speed of data transmission for these devices makes the technology of sending / receiving data via an internet targeted for optimization. The optimization could allow obtaining, in real-time, coordinates (latitude, longitude and altitude) of suitable quality for users of GPS (Global Positioning System) devices that have wireless Internet access, such as those used to control the eet, locomotion, navigation, agriculture, etc. . The use of the protocol NTRIP (Networked Transport of RTCM via Internet Protocol) in GPS applications is growing every day. Applications are available in C, which creates an opportunity for development with a focus on multiplatform environments. In this context, we propose an application, implemented in a multiplatform environment and the use of NTRIP, able to run on a mobile device for receiving GNSS data

Fadiga em compósitos 5HS carbono/epóxi processados via RTM: relação entre cargas axiais no plano e modos de delaminação

Pós-graduação em Engenharia Mecânica - FEG

Políticas de acesso ao cargo de diretor de escola pública da educação básica – novas perspectivas a partir da realidade do município de Franca/SP

Pós-graduação em Planejamento e Análise de Políticas Públicas - FCHS

Oscilador harmônico unidimensional via transformada unilateral de Fourier e mapeamento do potencial de morse unidimensional nos potenciais pseudo-harmônico e de kratzer tridimensionais

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Dados espectroscópicos de diterpenos labdânicos: uma análise teórica via RMN e DFT

Labdane diterpenes exhibit important bioactivities such as cardiovascular effects in rats as well as effects in the treatment of autoimmune diseases and Alzheimer syndrome. Recently, the labdane diterpenes ent-13-epi-manoil oxide, ribenone and ribenol were isolated from Croton palanostigma. The computational method DFT/B3LYP/cc-pVDZ was used to optimize the structures of these diterpenes and to calculate infrared data. Chemical shifts (δ_H and δ_C) of the minimum energy structures (local minimum) were calculated and compared with the experimental data. Comparison of the NMR data by simple linear regression (SLR) showed satisfactory statistical results with a correlation coefficient (R²) and predictive ability (Q²) of over 98%. The predicted NMR data were used to confirm the δ_H values that have not been published.

Oscilador harmônico unidimensional via transformada unilateral de Fourier e mapeamento do potencial de morse unidimensional nos potenciais pseudo-harmônico e de kratzer tridimensionais

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Diversidade genética em germoplasma tropical de cebola estimada via marcadores RAPD

A cebola é uma cultura de expressiva importância socioeconômica para o Brasil. Marcantes contribuições para o desenvolvimento da cultura têm sido feitas utilizando-se germoplasma de cebola adaptado às regiões tropicais e subtropicais. Nesse contexto, o presente trabalho teve como objetivo estudar a diversidade genética existente em uma coleção de germoplasma potencialmente útil ao desenvolvimento de cultivares para essas regiões. Para isso, a variabilidade genética de um grupo de 21 acessos foi analisada via marcadores RAPD. Esses acessos ('Red Creole', 'Roxa IPA-3', 'Valenciana 14', 'Beta Cristal', 'Diamante', 'Composto IPA-6', 'Aurora', 'Bojuda Rio Grande', 'Alfa Tropical', 'Pêra IPA-4', 'Primavera', 'Belém IPA-9', 'Crioula Alto Vale', 'Conquista', 'Pira-Ouro', 'Vale-Ouro IPA-11', 'Franciscana IPA-10', 'Serrana', 'CNPH 6400', 'Petroline' e 'Baia Periforme') têm sido empregados como germoplasma e/ou foram desenvolvidos pelos programas de melhoramento genético de cebola conduzidos no Brasil. Dos 520 iniciadores ('primers') utilizados na triagem inicial, somente 38 confirmaram polimorfismos entre os 21 acessos. Esses 38 'primers' produziram 624 amplicons, dos quais 522 (83,7%) foram monomórficos e 102 (16,3%) polimórficos. Com base nos padrões revelados, seis grupos foram formados de acordo com a similaridade média global entre os acessos (= 0,72). Somente um desses seis grupos englobou mais de um acesso. O grupo principal (formado por 16 acessos) incluiu, predominantemente, as cultivares que apresentam no seu pedigree a contribuição de 'Baia Periforme' ('Diamante', 'Composto IPA-6', 'Aurora', 'Bojuda Rio Grande', 'Conquista', 'Pira-Ouro', 'Serrana', 'Vale-Ouro IPA-11', 'Baia Periforme', 'Primavera', 'Franciscana IPA-10', 'Belém IPA-9', 'Crioula Alto Vale', 'Petroline', 'Pêra IPA-4' e 'Alfa Tropical'). As cultivares 'Red Creole', 'Roxa IPA-3', 'Beta Cristal', 'CNPH 6400' e 'Valenciana 14' formaram agrupamentos isolados e distintos do grupo 'Baia Periforme', revelando, dessa forma, divergência genética entre essas cinco populações e o grupo principal. Verificou-se que os materiais estudados possuem base genética relativamente estreita, apresentando, em sua grande maioria origem na população 'Baia Periforme'. Existem, no entanto, alguns materiais divergentes, cuja diversidade pode ser explorada em programas de melhoramento.

Administração de antibióticos por via subcutânea: uma revisão integrativa da literatura

OBJETIVO: Caracterizar os artigos científicos relacionados ao uso de antibióticos por via subcutânea em pacientes com difícil acesso venoso em cuidados paliativos quanto à tolerância local e eficácia terapêutica. MÉTODOS: Revisão integrativa da literatura realizada nas bases de dados LILACS, CINAHL, PUBMED, EMBASE e Biblioteca Cochrane, utilizando-se como referencial teórico a Prática Baseada em Evidências. RESULTADOS: 17 artigos foram selecionados com dez antibióticos diferentes, sendo o Ceftriaxona, o antibiótico mais estudado. Constatou-se a eficácia terapêutica com base nos parâmetros farmacocinéticos e clínicos. A tolerância local esteve associada à maior diluição dos antibióticos. Com administração de aminoglicosídeos, observaram-se lesões graves e necrose tecidual. A baixa tolerância reforça a restrição de uso apenas para essa classe de antibióticos. CONCLUSÃO: As previsões de eficácia terapêutica e a boa tolerância sugerem uma possibilidade a ser considerada quando se deseja uma via de administração parenteral alternativa, porém recomenda-se cautela, visto que nenhum dos estudos avaliou pacientes em cuidados paliativos.