Conventional and unconventional reservoirs are both critical in oilfield developments. After waterflooding treatments over decades, the petrophysical properties of a conventional reservoir may change in many aspects. It is crucial to identify the variations of these petrophysical properties after the long-term waterflooding treatments, both at the pore and core scales. For unconventional reservoirs, the productivity and performance of hydraulic fracturing in shales are challenging because of the complicated petrophysical properties. The confining pressure imposed on a shale formation has a tremendous impact on the permeability of the rock. The correlation between confining pressure and rock permeability is complicated and might be nonlinear. In this thesis, a series of laboratory tests was conducted on core samples extracted from four U.S. shale formations to measure their petrophysical properties. In addition, a special 2D microfluidic equipment that simulates the pore structure of a sandstone formation was developed to investigate the influence of injection flow rate on the development of high-permeability flow channels. Moreover, the multiple linear regression (MLR) model was applied with the predictors based on the development stages to quantify the variations of reservoir petrophysical properties. The MLR model outcome indicated that certain variables were effectively correlated to the permeability. The 2D microfluidic model demonstrated the development of viscous fingering when the injection water flow rate was higher than a certain level, which resulted in reduced overall sweep efficiency. These comprehensive laboratory experiments demonstrate the role of confining pressure, Klinkenberg effect, and bedding plane direction on the gas flow in the nanoscale pore space in shales. / Master of Science / Conventional and unconventional hydrocarbon reservoirs are both important in oil-gas development. The waterflooding treatment is the injection of water into a petroleum reservoir to increase reservoir pressure and to displace residual oil, which is a widely used enhanced oil recovery method. However, after waterflooding treatments for several decades, it may bring many changes in the properties of a conventional reservoir. To optimize subsequent oilfield development plans, it is our duty to identify the variations of these properties after the long-term waterflooding treatments, both at the pore and core scales. In unconventional reservoirs, hydraulic fracturing has been widely used to produce hydrocarbon resources from shale or other tight rocks at an economically viable production rate. The operation of hydraulic fracturing in shales is challenging because of the complicated reservoir pressure. The external pressure imposed on a shale formation has a tremendous impact on the permeability of the rock. The correlation between pressure and rock permeability is intricate. In this thesis, a series of laboratory tests was conducted on core samples to measure their properties and the pressure. Moreover, a statistical model was applied to quantify the variations of reservoir properties. The results indicated that certain reservoir properties were effectively correlated to the permeability. These comprehensive investigations demonstrate the role of pressure, special gas flow effect, and rock bedding direction on the gas flow in the extremely small pore in shales.

There have been thousands of studies on teams and their performance, but there are still many unanswered questions. An important one is how an organization's reward structure supports the growing trend of using teams. Many organizations implement teams without changing the organizational systems to align with and support the use of teams, i.e., training, feedback, information and reward systems. As predicted by many authorities in the field of team effectiveness research, these teams often fail. One organizational subsystem that has been determined to be important is the reward structure. If the reward structure is not changed to support a team-based structure, the misalignment could negatively impact team effectiveness. This research investigated the relationship between reward structure and team effectiveness using a laboratory experiment. This experiment involved groups of students working as a team on a design problem. The independent variable is the type of reward structure, manipulated over three levels: interdependent (group), independent (individual) and mixed rewards (both group and individual). The experiment used a design task, intended to be more representative of project team work where team members were assigned a functional discipline and worked together to solve a design problem. The primary dependent variable in this study was team effectiveness: team performance as measured by the quality of the team's design, satisfaction of team members, and the ability and desire of team members to work together in the future. Other control variables investigated for their effect on these dependent variables included: cooperative behaviors, reward valence, effort, and autonomy preferences. Few significant effects of reward structure were found. The reward treatment had a significant main effect on both cooperation and effort, but little difference existed between reward treatments. Some unusual results were found in the relationship between effort and cooperation with performance. Both effort and cooperation were negatively related to team performance. Cooperation, satisfaction and ability to exist were all found to be correlated. No one reward structure was found to be significantly better than any of the others in terms of team effectiveness or team process. / Master of Science

Les fonctions magnétiques sont aujourd'hui omniprésentes dans les systèmes Lab-on-Chip. Une découverte surprenante est que tandis que la recherche Lab-on-Chip se concentre sur la miniaturisation, les fonctions magnétiques sur puce sont généralement assurées par des aimants centimétriques. Comparés à ces aimants centimétriques, les champs générés par les micro-aimants bénéficient de lois d'échelle conduisant à des gradients de champ considérablement amplifiés et donc à des forces magnétiques proportionnellement accrues. Le but de cette thèse était de démontrer le potentiel des Lab-on-Chips à base de micro-aimants. Les micro-aimants haute performance ont été intégrés avec succès dans les matériaux Lab-on-Chip les plus pertinents, y compris le polymère, le silicium et le papier. Nous avons étudié des fonctions sur puce basées sur l'interaction de structures mécaniques et de micro-aimants actionnés par des gradients magnétiques, des forces et des couples. Enfin, nous avons simulé, fabriqué et testé une variété de nouvelles puces couvrant un large champ d'applications telles que les études cellulaires-mécaniques, la magnétophorèse, la manipulation de fluides sur puce et le diagnostic auprès du patient. Nous concluons que les micro-aimants intégrés présentent un grand potentiel pour les applications de laboratoire sur puce et devraient être plus largement exploités. / Magnetic functions are nowadays ubiquitous in Lab-on-Chip systems. A surprising finding is that while Lab-on-Chip research focalizes on miniaturization, on-chip magnetic functions are usually driven by centimetric magnets. Compared to those centimetric magnets, fields generated by micro-magnets benefit from scaling laws leading to dramatically increased field gradients and thus proportionally improved magnetic forces. The aim of this thesis was to demonstrate the potential of micro-magnet based Lab-on-Chips. High-performance micro-magnets were successfully integrated in the most relevant Lab-on-Chip materials including polymer, silicon and paper. We studied on-chip functions based on the interaction of mechanic structures and micro-magnets actuated by magnetic gradients, forces and torque. Finally, we simulated, fabricated and tested a variety of new chips covering a large field of applications such as cell-mechanics studies, magnetophoresis, on-chip fluid handling and Point-of-Care diagnostics. We conclude that integrated micro-magnets show great potential for lab-on-chip applications and should be more widely exploited.

A presente tese é o resultado de um complexo trabalho de instrumentação em Eletroforese Capilar (CE) com detecção condutométrica sem contato (C4D) visando à análise de biomoléculas. No que diz respeito à instrumentação, dois equipamentos de CE (H1 e B1), que possuem um sistema único de eletrólise separada (MSE), foram desenvolvidos. H1 possui apenas um capilar, e nele foi desenvolvida a maioria dos experimentos apresentados nesse trabalho. Neste equipamento, foi implementado um sistema de marcas térmicas, cuja aplicação foi demonstrada na correção de variações nos tempos de migração dos íons Na+ e K+ presentes em clara de ovos. Também realizamos a separação e detecção (10 µmol·L-1 ) de proteínas entre 12 e 66 kDa, comprovando que a detecção dessas moléculas é factível, desde que se use agentes que evitem a adsorção. Experimentos de separação e detecção de quitooligossacarídeos produzidos enzimaticamente também foram desenvolvidos em H1. Com o uso de NaOH como eletrólito de corrida acrescido de acetonitrila como agente modificador, verificamos a separação completa de seis quitooligossacarídeos (C1 a C6) com limites de detecção e quantificação inferiores a 3 µmol·L-1 e 10 µmol·L-1 , respectivamente. Após ensaios enzimáticos dos substratos C2 a C6 com a quitinase purificada de um besouro Tenebrio molitor (TmChi), observamos que esta cliva com baixíssima eficiência tanto C2 como C3. A mesma é capaz de clivar C4 produzindo C2 e sua ação sobre C5 gera C2 e C3, sendo este o substrato de maior afinidade. C6 também é clivado por essa quitinase, gerando, contudo, C2 ou C3, o que indica que ela é uma endoquitinase. O equipamento B1 possui oito capilares e oito detectores condutométricos sem contato, possuindo a maior relação sinal/ruído a 1 MHz e 4 Vpico-a-pico. O equipamento possibilita a separação simultânea de até oito amostras distintas com quatro possíveis eletrólitos e potenciais de trabalho. Nesse equipamento, foram desenvolvidas as separações dos vinte aminoácidos proteinogênicos, usando-se duas condições distintas de separação, ambas em meio ácido. Separações em meio básico e com potenciais de separação variados também foram avaliadas. Além dos sistemas H1 e B1, também foi desenvolvido um microchip em PDMS com um biorreator enzimático (IMER) para detecção de glicose. A detecção de peróxido formado pela ação da enzima glicose oxidase presente no IMER foi realizada por amperometria. O chip apresentou as melhores condições de separação e detecção desse açúcar usando-se eletrodo de trabalho a 0,9V, pH 8,5 e separação a 1100 V. Foi verificada uma relação linear entre as concentrações de 0,1 a 6,2 mmol·L-1 de glicose injetada, com relação ao pico de corrente obtido. Com as condições otimizadas do chip, determinou-se a concentração de glicose em amostra de refrigerante, obtendo-se uma concentração de 216 mmol·L-1 , valor semelhante ao obtido em literatura. / This work shows the development of two equipments (H1 and B1) of capillary electrophoresis (CE) with contactless conductivity detection (C4D) applied to the analysis of biomolecules. They have a system named MSE (module for separated electrolysis) that avoids the harmful effect of electrolysis. H1 have only one capillary and the majority of the experiments presented here were developed in this equipment. It also have a system of thermal marks (TM) used to correct the EOF effect on the migration of ions Na+ e K+ in egg white. We also developed the separation and detection of proteins (10 µmol·L-1) between 12 an 66 kDa, showing that C4D can be used to detect these molecules using substances to avoid adsorption on the capillary wall. Experiments of separation and detection of chitooligosaccharides enzymatically produced were also developed in H1. By using NaOH and acetonitrile as the electrolyte, we did the complete separation of six chitooligosaccharides (C1 to C6) with limits of detection and quantification less than 3 µmol·L-1 and 10 µmol·L-1 , respectively. After the enzymatic assays of C2 to C6 with the chitinase purified from the beetle Tenebrio molitor (TmChi), it is observed that this enzyme cut these substrates with very low efficiency, as expected. This enzyme also cut C4 producing C2 and cut C5 producing C2 and C3. C5 is the best substrate for this enzyme. C6 produces C2 and C3, showing that this enzyme is a endo- chitinase type. The equipment B1 has eight capillaries and eight C4D detectors with the best signal/noise ratio at 1 MHz e 4 Vpeak-to-peak . By using B1, it is possible run up to eight different samples with four different electrolytes and separation potentials. In this equipment, we develop the separation of 20 proteinogenic amino acids (AAs) using two different separation conditions at low pH. Separations of these molecules using high-pH electrolytes and with different potentials were also demonstrated. The development of a microchip of PDMS with an immobilized enzyme reactor (IMER) to the glucose detection was also constructed. The detection of hydrogen peroxide produced by the enzyme glucose oxidase linked on the IMER was measured by amperometry. The performance of this chip was evaluated with glucose and peroxide injections. The best potential for the oxidation of the hydrogen peroxide was 0.9V, using electrolyte at pH 8.5 and 1100 V as the potential of separation. A linear curve was observed between peak current and glucose concentration in the range from 0.1 up to 6.2 mmol·L-1 . Determinations in soda shows 216 mmol·L-1 of glucoce, that is a good agreement with other reports.

Este estudo tem por objetivo o desenvolvimento de uma metodologia de fabricação de sistemas Lab On Chip, úteis no estudo de processos celulares, a partir da adaptação de tecnologias próprias da microeletrônica. Foram exploradas todas as etapas envolvidas na fabricação de sistemas Lab On Chip em Poli-Di-Metil-Siloxano e desenvolvidos protocolos de fabricação de moldes, técnicas de moldagem e processos de ativação de PDMS com plasma de oxigênio para sua solda química sobre diferentes materiais, obtendo uniões irreversíveis que permitem a integração com outras tecnologias como a microeletrônica em silício e o encapsulamento com cerâmica verde, completando uma metodologia que permite a prototipagem de dispositivos micro-fluídicos de multicamadas com um nível de sofisticação comparável ao estado da arte. Foi desenvolvido o protótipo de um equipamento ótico para litografia por projeção que permite a fabricação de máscaras óticas com resolução de 5 m e oferece a possibilidade de litografia em escala de cinzas para gerar canais e estruturas com relevos arbitrários. Foram adicionalmente abordados três problemas de biofísica celular, para os quais foram propostos novos dispositivos para separação de células móveis de acordo às suas velocidades lineares, dispositivos para crescimento confinado de bactérias e dispositivos para manipulação da curvatura de membranas celulares. / The objective of this study is the development of a methodology for the fabrication of Lab On Chip systems, useful for the analysis of cellular processes, through the adaptation of technologies from microelectronics. All the steps involved with the fabrication of Lab on Chip system in Poly-Di-Methil-Siloxane (PDMS) were explored, developing protocols for mold fabrication, molding techniques and processes for oxygen plasma activation of PDMS for its bonding to different materials, achieving irreversible bonds that enable the integration with other technologies such as silicon microelectronics and green tape packaging. All this techniques constitute a methodology that allows the prototyping of multilayer microfluidic devices comparable with state of the art devices. It was developed the prototype of optical equipment for projection lithography capable of mask fabrication with 5 m resolution, and which offers also the capability of gray scale lithography for the generation of free form microchannels. Additionally three different problems in cellular biophysics where boarded, proposing new devices for the separation of motile cells according to their linear speeds in liquids, new devices for constrained bacterial growth and for curvature manipulation of cell membranes.

Reducing cost and time is a major concern in clinical diagnostics. Current molecular diagnostics are multi-step processes that usually take at least several hours or even days to complete multiple reagents delivery, incubations and several washing processes. This highly labor-intensive work and lack of automation could result in reduced reliability and low efficiency. The Laboratory-on-a-chip (LOC), taking advantage of the merger and development of microfluidics and biosensor technology, has shown promise towards a solution for performing analytical tests in a self-contained and compact unit, enabling earlier and decentralized testing. However, challenges are to integrate the fluid regulatory elements on a single platform and to detect target analytes with high sensitivity and selectivity. The goal of this research work is to develop an AC electrokinetic (ACEK) flow through concentrator for in-situ concentration of biomolecules and develop a comprehensive understanding of effects of ACEK flow on the biomolecule transport (in-situ concentration) and their impact on electronic biosensing mechanism and performance, achieving automation and miniaturization. ACEK is a new and promising technique to manipulate micro/bio-fluids and particles. It has many advantages over other techniques for its low applied voltage, portability and compatibility for integration into lab-on-a-chip devices. Numerical study on preconcentration system design in this work has provided an optimization rule for various biosensor designs using ACEK technique. And the microfluidic immunoassay lab-chip designed based on ACET effect has showed promising prospect for accelerated diagnostics. With optimized design of channel geometry, electrode patterns, and properly selected operation condition (ac frequency and voltage), the preconcentration system greatly reduced the reaction time to several minutes instead of several hours, and improved sensitivity of the assay. With the design of immunoassay lab-chip, one can quantitatively study the effect of ACET micropumping and mixing on molecular level binding. Improved sensors with single-chip form factor as a general platform could have a significant impact on a wide-range of biochemical detection and disease diagnostics including pathogen/virus detection, whole blood analysis, immune-screening, gene expression, as well as home land security.

As the dangers of teens and the internet make media headlines, Jennifer Shapka sifts through the fact and fiction of adolescent internet use.

Darbe ištirtos ir palygintos dviejų elektrofotografinių mašinų „Xerox DC5000“ ir „Conica Minolta 6500“ spalvų reprodukavimo galimybės. Tyrimas buvo atliekamas dviem spaudos mašinomis po tam tikro spaudų skaičiaus atspausdinant kalibracinį testą (lapą su specialiai spektrofotometrui paruoštais vienodo dydžio įvairių atspalvių kvadratėliais, kuriuose yra skirtingas visų keturių CMYK spalvų rastrinių taškų skaičius), kurio spalvų intensyvumas buvo matuojamas spektrofotometru „Efi ES–1000“. Nustatyta, kad spaudos mašinos „Xerox“ reprodukuojamų spalvų sodris didesnis lyginant su „Minolta“, tai lemia spaudo padengimas laku, kuris sukelia veidrodinį efektą, eliminuojama patenkanti į matavimo prietaisą išsklaidyta šviesa. Nustatytas savikalibracinės sistemos netobulumas bei abiejų mašinų spaudų skaičius, po kurio mašina turi buti kalibruojama. Darbą sudaro 7 dalys: įvadas, literatūros apžvalga, tyrimų metodika, rezultatai ir jų aptarimas, išvados ir rekomendacijos, literatūros sąrašas, priedai. Darbo apimtis – 57 p. teksto be priedų, 3 lentelės, 33 paveikslai, 15 bibliografinių šaltinių. Darbo priedai pridedami darbo pabaigoje. / The research regarding colour reproduction possibilities of two electrographic machines “Xerox DocuColor 5000” and “Conica Minolta Bizhub pro C6500” was made. In it two stamped machines were used, which had to stamp fixed numbers of calibration test (a paper with specially made, same size and various colours quadrants for spectrofotometer, where is different number of all four CMYK bitmap colour dots), which colour intensity was measured with using spaectrofotometer “Efi ES-1000”. The results have shown that “Xerox” machine has larger colour reproduction depth comparing to “Minolta” . This condition is made because of varnish that covers stamp. It creates specular effect and eliminates resolved light that comes to measuring devices. Self calibrating system cracks were discovered as well. Also two machines have to be calibrated after fixed number of stamps. Thesis has 7 parts: Introduction, literature review, research methodology, results, results discussion, conclusion and recommendation, literature list, appendix. Thesis consist of: 57p. text without appendix, 3 tables, 33 pictures, 15 bibliographical.

Made available in DSpace on 2015-05-14T13:21:46Z (GMT). No. of bitstreams: 1 parte1.pdf: 2204692 bytes, checksum: df26e8eadaeacfb0702b39229f465ea2 (MD5) Previous issue date: 2010-03-17 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work describes the construction of a new flow-batch analyzer (FB) in micro scale (micro Flow-Batch-μFBA) using the technique of deep ultraviolet photolithography with commercial resin based in urethane acrylate oligomers (UA). The device was constructed from the union of two layers of pre-polymerized resin of 3.4 mm thick each, thus forming a single structure. The main feature of the new device is the small volume of its analysis chamber, which can be 100-200 μL, allowing the homogenization of reagent solutions in a time of 2.s. In this sense, the decrease in reagents consumption and hence generation of waste (ten times smaller than a conventional FB), wich is in line with the requirements of green chemistry and with the new position of the eco-efficiency. The system offers the following progress in relation to micro fabrication with urethane acrylate resin: (i) depth control of the channels during photolithography; (ii) axial mixer incorporated; (iii) LED - Light emitting diode (530 nm) and detector (photodiode) coupled to the device body; The depth control of the channels allows adjustment of the volume of the chamber and the LED to the mixing chamber. The LED and detector connector pins is the elements that makes the device fixed on its box. In this first assembly, system were used in photometric determination of Fe (II) in pharmaceuticals. The model for the calibration curve was validated by analysis of variance (ANOVA), and their analytical results were compared with those obtained in batch by the reference method, the application of paired t-test found no statistically significant differences at a confidence level of 95%. / No presente trabalho é descrita a construção de um novo analisador Flow- Batch (FB) em escala micro (micro Flow-Batch - μFBA) utilizando a técnica de fotolitografia profunda no ultravioleta com resina comercial à base de oligômeros uretano e acrilato (UA). O dispositivo foi construído a partir da união de duas camadas da resina pré-polimerizada de 3,4 mm de espessura cada uma, formando assim uma estrutura única. A característica principal do novo dispositivo é o pequeno volume da câmara de análise, que pode ser de 100 a 200 μL, permitindo a homogeneização das soluções reagentes em um tempo de 2.s. Nesse sentido, a diminuição do consumo de reagentes e, conseqüentemente, de resíduos gerados (dez vezes menor que um FB convencional), apontam na direção dos requisitos da química verde e se alinham com a nova postura da ecoeficiência. O sistema apresenta os seguintes avanços em relação à microfabricação com resina uretanoacrilato: (i) controle da profundidade dos canais durante a fotolitografia; (ii) agitador do tipo axial incorporado; (iii) LED emissor de luz (530nm) e detector (fotodiodo) acoplados ao corpo do dispositivo. O controle da profundidade permitiu o ajuste do volume da câmara e do LED à câmara de mistura. Os próprios pinos conectores do LED e do detector foram utilizados como elementos de fixação da peça em sua caixa. Nesta primeira montagem, o sistema foi empregado na determinação fotométrica de Fe (II) em medicamentos. O modelo para a curva de calibração foi validado através da Análise de Variância (ANOVA), e seus resultados analíticos foram comparados com aqueles obtidos em análises de referência através da aplicação do teste-t emparelhado, não apresentando diferenças estatísticas significativas a um nível de confiança de 95%.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2017-12-20T12:00:43Z No. of bitstreams: 1 giselenogueiraforgaca.pdf: 1203684 bytes, checksum: 59314b5e0521d179b046af64248e362c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2017-12-22T11:57:21Z (GMT) No. of bitstreams: 1 giselenogueiraforgaca.pdf: 1203684 bytes, checksum: 59314b5e0521d179b046af64248e362c (MD5) / Made available in DSpace on 2017-12-22T11:57:21Z (GMT). No. of bitstreams: 1 giselenogueiraforgaca.pdf: 1203684 bytes, checksum: 59314b5e0521d179b046af64248e362c (MD5) Previous issue date: 2017-08-18 / Fraudes em lácteos é um problema do ponto de vista econômico, já que traz prejuízos ao consumidor, e em alguns casos, são caracterizadas como um problema de saúde pública, visto que essas podem reduzir os componentes nutritivos originais do alimento ou mesmo provocar contaminação microbiológica, química ou física. Por este motivo, metodologias que visam a comprovação da autenticidade dos produtos lácteos têm sido desenvolvidas. Desse modo, este trabalho teve como objetivo avaliar o método lab-on-a-chip para a detecção de fraude em leite de vaca pela adição de soro de queijo. Sendo assim, amostras de leite cru, pasteurizado, UHT e em pó foram adicionadas com soro de queijo, simulando este tipo de fraude, em níveis crescentes 0; 1; 2,5; 5; 10; 20; 30; 50% (v/v). Todas as amostras foram submetidas a eletroforese lab-on-a-chip e SDS-PAGE com o objetivo de detectar fraude. Os resultados obtidos utilizando as duas metodologias foram satisfatórias quanto a separação e quantificação das proteínas do leite. Somente foi possível detectar a fraude a partir de 1% de adição de soro de queijo para os quatro tipos de leite testados pela técnica lab-on-a-chip. Com base nestes resultados, conclui-se que esse método pode ser aplicado como um mecanismo de triagem para a detecção de fraude em leite nas rotinas em laboratórios da indústria. Entretanto ressalta-se que a técnica lab-on-a-chip deve ser submetida a um processo de validação de metodologia para que possa ser utilizada na rotina em laboratórios de qualidade do leite. / Dairy fraud is a problem from the economic point of view, since it causes harm to the consumer and in some cases is characterized as a public health problem, since these frauds can reduce the original nutritional components of the food or even cause microbiological contamination, chemical or physical. For this reason, methodologies aimed at proving the authenticity of dairy products have been developed. Therefore, this work aimed to evaluate the lab-on-a-chip method for the detection of fraud in cow's milk by the addition of cheese whey. Therefore, samples of raw, pasteurized, UHT and powdered milk were added with cheese whey, simulating this type of fraud, at increasing levels 0; 1; 2.5; 5; 10; 20; 30; 50% (v/v). All samples were submitted to lab-on-a-chip electrophoresis and SDS-PAGE with the aim of detecting fraud. The results obtained using the two methodologies were satisfactory regarding the separation and quantification of milk proteins. It was only possible to detect fraud from 1% addition of cheese whey to the four milk types tested by the lab-on-a-chip technique. Based on these results, it was conclude that this method can be applied as a screening mechanism for the detection of milk fraud in routines in industry laboratories. However, it is emphasized that the lab-on-a-chip technique must be submitted to a methodology validation process so that it can be used routine in milk quality laboratories.