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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
871

Characterization of Scanning Mobility Particle Sizers For Use With Nanoaerosols

Henderson, Michael R. 05 April 2018 (has links)
The purpose of this study was to evaluate the performance of scanning mobility particle sizers in the characterization of nanoaerosols. A sampling chamber was constructed from aluminum and tempered glass, had a volume of 4.6 cubic feet, and was designed for the introduction of aerosols and dilution air, maintenance of aerosol concentration, and continuous exhaust of chamber air. Penetration and aerosol distribution tests were conducted within the chamber. An aerosol generation and measurement system comprised of nitrogen gas, BGI 3 jet Collison Nebulizer, diffusion dryer, aerosol charge neutralizer, mixing chamber, critical orifice, hygrometer, condensation particle counter, scanning mobility particle sizer, air sampling pump, air sampling cassettes, and a vacuum pump was assembled. A BGI 3 jet Collison Nebulizer was used to generate the nanoparticle aerosols. The two types of nanoparticle aerosols utilized in the experiment were salt (NaCl) and polystyrene latex (PSL) spheres. Relative humidity and temperature measurements were obtained within the chamber. Real-time, direct-reading particle measurement instruments including a condensation particle counter (CPC) (TSI, Model 3007), and three scanning mobility particle sizer (SMPS) instruments (Particle Measuring Systems, Nano-ID NPS500; TSI, NanoScan SMPS Nanoparticle Sizer Model 3910) were used for particle measurements. For each test run, two air samples were collected on membrane filters for electron microscopy (EM) analysis. Eight trials were conducted using NaCl nanoaerosols, and twelve trials were conducted using PSL spheres. The selected particle sizes for the experiments were 57 nm, 92 nm, 147 nm, and 220 nm. For the NaCl nanoaerosol suspensions, the SMPS lines of fit were log-normally distributed and predominantly parallel. The geometric standard deviation (GSD) of these distributions was approximately 1.7, which confirms that the distributions were approximately the same. In these experiments, instrument 3 identified a higher percentage of NaCl particles within the size range intervals of the selected NaCl size parameter, and the count median diameters (CMDs) for the instrument 3 measurements were closer to the selected NaCl size parameter more often than the other instruments. This suggests that instrument 3 was more responsive than the other instruments to the selected size range and the selected NaCl size parameters. The electron microscopy (EM) lines of fit for the NaCl experiments were predominantly parallel with the SMPS lines of fit, suggesting that the log-normally distributions are similar. The GSD of EM distributions was approximately 1.8, which confirms that the distributions were approximately the same as the SMPS distributions. Results from the regression plots demonstrated that the main effects and interaction were statistically significant with a p<0.0001. The coefficient of determination, R2, for the regression lines was 0.87. The post-hoc Tukey HSD results identified a significant difference between the instrument 3 dataset, and the datasets for instruments 1 and 2. For the PSL nanoaerosol suspensions, the SMPS lines of fit were log-normally distributed and predominantly parallel. The GSD of these distributions was approximately 1.3, which confirms that the distributions were approximately the same. In these experiments, instrument 2 identified a higher percentage of PSL particles within the size range intervals of the selected PSL size parameter, and instrument 2 CMDs were closer to the selected PSL size parameter more often than the other instruments. This suggests that instrument 2 was more responsive than the other instruments to the selected size range and the selected PSL size parameters. Results from the regression plots demonstrated that the main effects and interaction were statistically significant with a p<0.01. The coefficient of determination, R2, for the regression lines was 0.44. The post-hoc Tukey HSD test identified a significant difference between the instrument 3 dataset and the instrument 1 dataset. Potential sources of variability include solution water background contamination, surfactants in the PSL solution, and agglomeration. The performance of all the scanning mobility particle sizers compared in these experiments was acceptable for research and field applications, but caution should be taken when comparing the measurements of SMPS, especially SMPS from different manufacturers.
872

Finanční nástroje revitalizace brownfields vybraného regionu / Financial instruments for the revitalization of brownfields in selected region

MENCL, Lukáš January 2016 (has links)
The aim of this master thesis was to evaluate financial instruments for the revitalization of brownfields. Brownfield is an estate that is not currently being used it´s neglected and requires some renovation. In the first part of this thesis there are the financial instruments described on the revitalization of brownfields at national and European level. The history of financial instruments for the revitalization of brownfields in the Czech Republic is described here, too. You can also find here some examples of successful revitalization at national and international levels. The second part focuses on the analysis of brownfields in area of Jindřichohradecko. In total there are 8 registered brownfields analyzed and their possible utilization and financing is designed. The research was carried out by using questionnaires for citizens, mayors and owners of brownfields. The results were compiled into graphs and subsequently described. It was made a review of brownfields to determine the current state of these objects. Public awareness of the issue of brownfields was also examined.
873

Resistência à flexocompressão de instrumentos endodônticos indicados para canais atresiados e sua correlação com as características morfométricas / Buckling resistance of pathfinders and its geometry

Georgiana Amaral 07 April 2009 (has links)
O objetivo deste estudo foi avaliar a resistência à flexocompressão (flambagem) de instrumentos endodônticos empregados no cateterismo de canais radiculares atresiados e se esta varia conforme o comprimento. Flambagem é a deformação lateral apresentada por um instrumento quando submetido a uma força compressiva na direção de seu longo eixo. Foram utilizados instrumentos endodônticos C+File n 10, K-File n 10 (Dentsply-Maillefer, Suíça); CC+ n 10 e C-Pilot n 10 (VDW, Alemanha), HI-5 n 10 (Miltex, EUA), Pathfinder CS K2 e Pathfinder SS (SybronEndo, EUA), sendo dez amostras de cada marca comercial em diferentes comprimentos. As dimensões dos instrumentos, tais como diâmetros, comprimento útil, comprimento da parte de trabalho, conicidades, ângulos de inclinação das hélices, ângulo da ponta, forma de seu vértice e presença de ângulo de transição foram determinadas por meio de um microscópio óptico com dispositivo micrométrico acoplado a um computador (Pantec, Panambra, Brasil). Detalhes da forma das pontas e forma das seções retas transversais foram obtidas por meio de um microscópio eletrônico de varredura (MEV - JEOL, JSM-5800, Tókio, Japão). O ensaio de flambagem foi realizado empregando-se uma máquina de ensaio universal (EMIC, DL 10.000, Paraná) e consistiu na aplicação de uma força crescente na direção axial dos instrumentos avaliados, sendo registrada por um software até o deslocamento de 1 mm. A análise dos resultados pelo ANOVA e Tukey revelou que a força máxima para flambar os instrumentos foi maior para os da marca comercial C+File tendo os instrumentos Pathfinder SS apresentado os resultados menos favoráveis. Provavelmente a geometria, que se mostrou completamente distinta para cada grupo de instrumentos, influenciou no comportamento dos mesmos, embora o comprimento não tenha interferido na resistência à flexocompressão. / The aim of this study was to evaluate the buckling resistance of endodontic intruments during the pathfinding of constricted root canals and its lenght influence. Buckling is the elastic deformation of an instrument due to the compressive strenght in its axial direction. The instruments surveyed and tested were: C+File #10, K-File #10 (Maillefer, Switerzland), CC+#10, C-Pilot #10 (VDW, Germany), HI-5 #10 (Miltex, USA) and Pathfinder CS K2 and SS (SybronEndo, USA). Ten instruments from different brands with different lenghts were measured through a optical microscope (Pantec, Panambra, Brazil) aiming to register the diameters, total and useful lenght, taper, helical angles and tip angle, whereas tip details and cross sections were obtained through an electronic microscope MEV (JEOL, JSM-5800). The buckling test was performed at an universal testing machine (EMIC, DL 10.000, Brazil). The maximum load during the elastic deformation was measured by a software while applying increasingly pressure in the axial direction of each instrument till a 1mm deformation. The ANOVA e Tukey test analized the results and revealed that the C+File presented the highest buckling resistance while Pathfinder SS presented the worst results. Different designs might interfere with the results but, in general, the lenght did not have statistical influence.
874

Avaliação do efeito da afiação com diferentes técnicas sobre o ângulo de corte de curetas de Gracey

Andrade Acevedo, Roberto Antonio [UNESP] 18 August 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:33:29Z (GMT). No. of bitstreams: 0 Previous issue date: 2003-08-18Bitstream added on 2014-06-13T19:04:27Z : No. of bitstreams: 1 andradeacevedo_ra_dr_arafo.pdf: 2469845 bytes, checksum: 6aef2f449ff6364a09cca9dd4566f240 (MD5) / O presente trabalho teve por objetivo avaliar em fotomicrografias obtidas em microscópio eletrônico de varredura (MEV) o ângulo de corte de curetas de Gracey 5-6 em três níveis: afiação de fábrica, após ficarem sem corte e após serem reafiadas utilizando nove diferentes técnicas padronizadas de afiação: 1- face lateral da cureta contra a pedra Arkansas plana; 2- face coronal e posteriormente a lateral contra a pedra Arkansas plana; 3- pedra de Arkansas plana contra a face lateral da cureta; 4- cone de óxido de alumínio a baixa rotação contra a face coronal e em seguida a face lateral da cureta; 5- face lateral da cureta com pedra Arkansas 299; 6- face lateral da cureta com o aparelho padronizador Hu-Friedy; 7- face coronal da cureta com ponta de videa; 8- face coronal da cureta com ponta de videa e em seguida a face lateral com pedra de Arkansas plana; 9- afiação da face coronal com ponta de videa e em seguida pó abrasivo e roda de feltro rotatória na face lateral da cureta. Foram tomadas fotomicrografias (350X) do ângulo de corte e posteriormente avaliadas por um examinador calibrado através do índice do ângulo de corte. A analise estatística de Kruskal Wallis e comparações múltiplas mostraram que as técnicas 1 e 2 foram as melhores técnicas de afiação seguidas das técnicas 6, 5 e 8. As piores técnicas foram a 7, 9, 4, 0 e 3. A reafiação da face coronal das curetas produziu a formação de projeções metálicas não funcionais no ângulo de corte e finalmente não houve diferenças entre a afiação do extremo par e ímpar dos instrumentos em nenhuma das técnicas de afiação utilizadas. / A micrographs obtained by a scanning electron microscope (SEM) were used to evaluated the gracey 5-6 cutting edges as the come from manufacture, after they had been dull and after they were resharpened by several standard techniques: 1- lateral surface over a flat Arkansas sharp stone; 2- coronal surface and the a lateral surface over a flat Arkansas sharp stone; 3- lateral surface by passing a flat Arkansas sharp stone; 4- rotatory aluminum oxide stone over a coronal surface and then over a lateral face; 5- lateral surface by passing an Arkansas 299 stone; 6- lateral surface on Hu-Friedy sharp divice; 7- coronal surface by a Whittler Neivert Device; 8- coronal face by a Whittler Neivert Device and the a lateral surface over a flat Arkansas sharp stone; 9- coronal surface with a Whittler Neivert Device and a rotating, impregnated, felt wheel on the lateral surface. The cutting edges was blindly evaluated on micrographs (X350) by one calibrated examiner (cutting angle index). A statistical analysis showed that techniques 1 and 2 were the best ones followed by a 6, 5 and 8 techniques. The worst techniques were a 7, 9, 4, 0 and 3. Resharpened on the coronal face of curettes generated a non functional wire edges on the cutting edge angle and there were not differences between the paired and unpaired extreme of the instruments resharpened.
875

Esterilização de fresas carbide em fornos de micro-ondas domésticos. Efeito da capacidade. da potência, do meio da imersão, da quantidade e posição da amostra sobre o tempo de esposição

Pita, Ana Paula Gonçalves [UNESP] 14 July 2009 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:02Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-07-14Bitstream added on 2014-06-13T20:06:08Z : No. of bitstreams: 1 pita_apg_dr_arafo.pdf: 290018 bytes, checksum: ad154ba418a5be2bcb069526ffc6570a (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O uso do forno de micro-ondas para a esterilização tem sido proposto em diferentes áreas. O tempo da exposição necessário para esterilizar água deionizada contaminada em diferentes posições dentro do forno foi avaliado e um método da esterilização de fresas carbide foi avaliado, considerando sua imersão ou não em 2 ml e 10 ml de água ou o óleo, a capacidade do forno (27 e 38 l), o nível de potência (400 e 600 W) e diferentes quantidades de instrumentos irradiados ao mesmo tempo (1, 5 e 10 fresas). Este trabalho foi feito em três etapas consecutivamente. Primeiramente, 10 ml da água deionizada foi contaminada por um dos três micro-organismos (Bacilus subtilis, Escherichia coli, Cândida albicans). A amostra contaminada foi situada em uma das 15 posições determinadas pela combinação das posições horizontais (anterior, posterior, direita, esquerda e central) e das posições verticais (sobre o prato giratório, 3 cm ou 5 cm acima do prato giratório) e foi submetida à irradiação por microondas (580 W) por 0,5, 1, 2, 5, 6, 7 ou 8 minutos. Nas etapas subseqüentes, as fresas estéreis foram contaminadas individualmente pelos mesmos micro-organismos. Após a contamindação, foram individualmente submetidas à irradiação (580 W) por 1, 2, 3, 4, 8, 9, 16, 17 ou 20 min em um frasco vazio ou contendo 2 ou 10 ml de água ou de óleo mineral. Na última etapa, os instrumentos contaminados foram irradiados individualmente ou nos grupos (5 ou 10 fresas), a aproximadamente 400 ou 600 W, em um dos dois fornos (27 ou 38 l) durante: 0,5; 1; 2; 3; 4; 5; 6; 8; 9.5; 10; 11; 13 ou 14,5 minutos. Após a irradiação foram adicionados 10 ml de meio fluido no frasco contendo os espécimes irradiados, que foram incubados a 37°C durante 48 h (B. 11 subtilis e E. coli) ou a 28ºC durante 72 h (C. albicans) para avaliação do efeito da esterilização pela turvação do caldo... / The use of microwave oven for sterilization has been proposed in different fields. The exposition time required to sterilize contaminated deionized water in different positions was evaluated and a microwave sterilization method of dental carbide burs was tested considering their immersion or not in 2 ml or 10 ml of water or oil, the oven capacities (27 l and 38 l), the level power (400 and 600 W) and different amount of instruments irradiated at the same time (1, 5 and 10 burs). This work was done in three stages consecutively. First, 10 ml of deionized water were inoculated with three microorganisms (Bacilus subtilis, Escherichia coli, Candida albicans). The contaminated sample was located at one of the 15 positions determined by the combination of horizontal positions (anterior, posterior, right, left, centre) and vertical positions (on the glass plate, 3 cm over the glass plate level, 5 cm over the glass plate level) and microwaved (580 W) for 0.3, 1, 2, 5, 6, 7 or 8 minutes. In the subsequent stages, sterile burs were individually inoculated with the same microorganisms. The contaminated burs were microwaved at 580 W for 1, 2, 3, 4, 8, 9, 16, 17 or 20 min in the dry state or immersed in 2 or 10 ml of water or mineral oil. In last stage, the contaminated instruments were microwaved individually or in groups (5 or 10 burs), at approximately 400 or 600 W, into the two ovens for: 0,5; 1; 2; 3; 4; 5; 6; 8; 9,5;10; 11; 13 or 14,5 minutes. After irradiation sterile broth was added into the flask containing irradiated specimens and incubated at 37°C for 48h (B. subtilis and E. coli) or at 28ºC for 72h (C. albicans), the sterilization effect was verified by the turbidity test. This study suggests that the position of the sample must be considered in domestic microwaves ovens sterilization methods and the central position should be avoided. The presence of a liquid material in contact... (Complete abstract click electronic access below)
876

Organology of the Queen Mary and Lamont harps

Loomis, Karen Ann January 2015 (has links)
The metal strung harp indigenous to Ireland and Scotland from the Medieval period to the end of the 18th century was widely admired throughout its time period, and is now an important part of the cultural and musical heritage of both of these countries. This type of harp, known as the 'Irish harp', cláirseach, or clàrsach, currently has 18 known surviving instruments, including two sets of fragments. All of these harps are now too fragile to be played, therefore musicians and audiences wishing to explore the performance practice and repertory associated with them must rely on faithful replicas. The extensive knowledge and understanding of the construction of the surviving harps that is crucial to building these replica instruments is currently very limited, however. Although harps of this type enjoyed a long period of use dating back to the Medieval period, most surviving instruments post-date the beginning of the 17th century. Two harps belonging to the National Museum of Scotland, the 'Queen Mary' and 'Lamont', generally dated to circa the 15th century, are understood to be two of the oldest extant examples, making a study of their construction of particular interest. This dissertation presents the results of a comprehensive study of the construction of these two harps. A methodology was developed to address the issue of their uniqueness and fragility by combining the techniques used for non- and minimally destructive analysis of archeological artefacts with non-invasive medical diagnostic imaging. This study has utilized CT-scanning to provide three-dimensional radiography of each harp; XRF and SEM-EDX analysis to identify woods, metals, and pigments; photography and microscopy to record the decorative work, visible damage, repairs, and modifications; and a visual examination to assess the current state of each harp and to identify areas of interest for further analysis. The CT scanning was conducted at the Clinical Research Imaging Centre of Queen's Medical Research Institute, and the remainder of the analysis was conducted at the National Museums Scotland Collections Centre. Staff at both centres kindly facilitated the acquisition of the data for this study. Part I of this dissertation discusses the stringing of the instruments, presenting materials analysis of wire fragments, analysis of the effect of damage to the frames on the length and number of strings, and proposed reconstructions of the 'as-built' string lengths. Possible solutions for the pitch and gamut of each harp are also discussed. The construction of the harps is discussed where it is relevant to understanding the stringing. Part II presents a general discussion of the construction of each harp, including materials, decorative work, modifications, and signs of wear. This section also discusses evidence that may help establish dates of construction and timelines of modifications. Diagrams showing the dimensions of each harp are also presented. The implications of the results of this study for current understanding of these harps are discussed in detail and the methodology employed is discussed in terms of its applicability to future research of other surviving instruments.
877

Eletroestimulador funcional de oito canais com malha de realimentação utilizando Controlador Digital

Junqueira, Marcos Vinícius Nascimento [UNESP] 04 October 2013 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:22:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2013-10-04Bitstream added on 2014-06-13T19:48:53Z : No. of bitstreams: 1 junqueira_mvn_me_ilha.pdf: 2490518 bytes, checksum: 7e14b1f52c086453d1a4b7b8750cb97e (MD5) / Foi desenvolvido um Eletroestimulador Funcional Microcontrolado para geração de movimentos nos membros inferiores de paraplégicos, visando acelerar o processo de reabilitação. O estimulador neuromuscular é constituído por oito canais microcontrolados, com formas de onda de corrente bifásica, retangular e carga balanceada, com capacidade para fornecer correntes com amplitude de até 140 mA, utilizando modulação por largura de pulso (PWM). Foi implementado um controlador Proporcional Integral Derivativo (PID) embarcado para uso com o eletroestimulador, sendo possível determinar a energia a ser aplicada ao membro estimulado, de forma a mantê-lo em uma posição pré-estabelecida. O projeto desse controlador se baseou em um modelo matemático linear de segunda ordem, que representa o comportamento da força muscular devido a um estímulo elétrico. Para validação e teste do funcionamento do sistema, funções matemáticas que descrevem o comportamento fisiológico do membro inferior foram representadas por circuitos eletrônicos. Desta forma, neste projeto foi possível integrar o controlador, o estimulador e o modelo fisiológico do músculo, observando-se a resposta temporal durante a eletroestimulação, descartando, inicialmente, a realização de testes com pessoas, visando preservar a integridade física dos voluntários. Após a verificação do bom funcionamento do equipamento, realizou-se testes com voluntários aplicando o controle em malha fechada / A Microcontrolled Functional Electrical Stimulation (FES) system was developed for generating movements in the lower limbs of paraplegics in order to accelerate their rehabilitation process. The neuromuscular stimulator consists of eight channels, microcontrolled, rectangular, biphasic current waveform, balanced load, with the ability to deliver current with amplitude of 140 mA using pulse width modulation (PWM). A PID controller was implemented for using with the microcontrolled stimulator, and the energy to be applied to the stimulated member can be determined in order to keep the leg in a pre-determined position. The design of this controller was based on a linear second order mathematical model, which describes the behavior of a muscle strength due to an electrical stimulus. For validation and testing the microcontrolled electrical stimulator system, mathematical functions that represent the physiological behavior of the lower limbs were represented by electronic circuits. Thus, this project integrates the controller, the stimulator and the muscle model, observing the time response during electrical stimulation, avoiding testing it with patients and preserving the physical integrity of the volunteers. After verifying the proper operation of the equipment, tests with volunteers were carried out applying closed loop control
878

Implantacao de um programa de controle de qualidade em equipamentos de raios X por meio de medidores nao invasivos / Establishment of an X radiation equipment quality control programme using non invasive meters

LUCENA, RODRIGO F. de 09 October 2014 (has links)
Made available in DSpace on 2014-10-09T12:28:10Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:01:44Z (GMT). No. of bitstreams: 0 / Dissertacao (Mestrado) / IPEN/D / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP
879

Biosensor magnetoelástico para a detecção de Escherichia coli

Possan, André Luís 27 February 2015 (has links)
A Escherichia coli é uma bactéria que deve ser controlada na indústria alimentar e setor hospitalar. Biosensores magnetoelásticos oferecem a promessa de rápida identificação destes e de outros patógenos prejudiciais. Neste trabalho, tiras amorfas de Metglas 2826MB3 foram cortadas ao tamanho 5 mm x 1 mm, com uma serra de micro corte e, em seguida, foram revestidas com camadas finas de Au e Cr, como foi verificado pela análise de espessuras de filmes Rutherford Backscattering Spectroscopy (RBS). Foram estudadas várias superfícies dos sensores: 1) sensor as-cast, lado roda; 2) sensor as-cast, superfície livre; 3) superfície polida. Uma camada de cistamina (CYS) foi aplicada ao substrato magnetoelástico, formando monocamadas auto organizadas (SAM), seguido de anticorpos, utilizando um protocolo modificado de Hermanson. Foi utilizado a bactéria Escherichia coli ATCC 25922, um anticorpo primário anti E. coli para a formação do bioconjugado e um anticorpo secundário Goat IgG anti-rabbit H&L Alexa Fluor 488 para a microscopia de fluorescência por método imunológico. O crescimento da camada de cistamina foi caracterizado por espectroscopia de infravermelho com transformada de Fourier (FTIR) e microscopia eletrônica de varredura (MEV) para as superfícies. Os biosensores foram expostos a soluções de bactérias e a frequência de ressonância dos sensores foi medida com um analisador de impedância Agilent E5061B até 100 minutos, em 5 biosensores de cada tipo. As reduções na frequência de ressonância, que apresentam a captura de bactérias, foram medidos após a otimização da amplitude do sinal. Para tempos até 40 minutos, a altas taxas de captação foram observadas e, posteriormente, a saturação ocorreu. Os parâmetros associados com uma cinética de captura foram estudados para diferentes superfícies dos sensores. O sensor com uma superfície polida mostrou melhores resultados. Este trabalho mostra que os biosensores magnetoelásticos podem ser úteis para a detecção e quantificação de microrganismos. / Submitted by Ana Guimarães Pereira (agpereir@ucs.br) on 2015-06-16T18:27:50Z No. of bitstreams: 1 Dissertacao Andre Luis Possan.pdf: 5589898 bytes, checksum: 765d06f99a85653862a5df0706858320 (MD5) / Made available in DSpace on 2015-06-16T18:27:50Z (GMT). No. of bitstreams: 1 Dissertacao Andre Luis Possan.pdf: 5589898 bytes, checksum: 765d06f99a85653862a5df0706858320 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior. / Escherichia coli is a bacteria that must be controlled in the food industry and the hospital sector. Magnetoelastic biosensors offer the promise of rapid identification of these and other harmful pathogens. In this work, strips of amorphous Metglas 2826MB3 were cut to size (5 mm x 1 mm) with a micro-dicing saw and were then coated with thin layers of Cr and Au, as verified by Rutherford backscattering spectroscopy (RBS). Several sensor surfaces were studied: 1) as-cast strip, wheel side; 2) as-cast strip, free surface; 3) thinned and polished surface. A layer of Cystamine (CYS) was applied to the magnetoelastic substrate, forming a self-assembled monolayer (SAM), followed by antibodies, using a modified Hermanson protocol. For our Escherichia coli ATCC 25922, we used both a primary antibody anti E. coli and a secondary antibody Goat anti Rabbit IgG H&L Alexa Fluor 488. The cystamine layer growth was characterized by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The biosensors were exposed to solutions of bacteria and the resonant frequency of the sensors was measured with an Agilent E5061B impedance analyzer for times up to 100 minutes. Reductions in the resonant frequency, corresponding to bacteria capture, were measured after optimizing the signal amplitude. For times up to 40 minutes, high capture rates were observed and thereafter saturation occurred. Parameters associated with capture kinetics were studied for different sensor surfaces. The sensor with a polished surface was found the best results. This work shows that magnetoelastic biosensors may be useful for the detection and quantification of microorganisms.
880

Análise de três métodos de estimativa da evapotranspiração de referência para a região de Pradópolis - SP /

Balotta, Graciano Augusto Peviani. January 2011 (has links)
Orientador: José Eduardo Pitelli Turco / Banca: Adhemar Pitelli Milani / Banca: Renato Farias do Valle Júnior / Resumo: O objetivo desse trabalho foi avaliar três métodos de estimativa da evapotranspiração de referência (Hargreaves, Radiação Solar e Makkink), comparando-os com o método de Penman-Monteith, recomendado pela Organização das Nações Unidas para a Alimentação e Agricultura (FAO) como método padrão para estimativa da ETo, para o município de Pradópolis - SP. Para esse fim foi instalada no posto agrometeorológico da cidade de Pradópolis - SP uma estação meteorológica automatizada. Por intermédio desta estação foram obtidas medidas da radiação solar global, temperatura do ar, umidade relativa do ar e velocidade do vento. A análise dos resultados foi feita por uma técnica que considera os erros da ET0. O resultado da avaliação dos métodos indica um melhor ajuste para estimativa da ETo para o método de Hargreaves. Os métodos de Makkink e Radiação Solar não obtiveram um ajuste satisfatório com o do Penman-Monteith. Para avaliar métodos de estimativa da evapotranspiração deve-se considerar os erros da estimativa da ETo, evitando possíveis erros de avaliação / Abstract: The aim of this investigation was to evaluate two reference methods to Monteith method, recommended by the Food and Agricultural Organization of the United Nations (FAO) as the standard method for estimating ETo in Pradópolis - SP. To this data collection, an automated weather station was installed in the meteorological station at Pradópolis - SP. Through estimate evapotranspiration (Hargreaves, Radiation and Makkink), compared to Penman-this station, we obtained measures of global solar radiation, air temperature, relative humidity and wind speed. The analysis was done by a technique that considers the mistakes of ETo, which depends on the combination of the errors of the variables that make up the estimating equations, derived from the measurement instruments used to obtain these variables. The aftermath showed a better adjustment to Hargreaves. Makkink, and Radiation methods are different from Penman-Monteith, therefore, they cannot be compared. To evaluate methods to estimate evapotranspiration and avoid possible evaluation errors, ETo estimate errors must be considered / Mestre

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