861 resultados para Process Analytical Technology (PAT)
Resumo:
In this report, we describe a rapid and reliable process to bond channels fabricated in glass substrates. Glass channels were fabricated by photolithography and wet chemical etching. The resulting channels were bonded against another glass plate containing a 50-mu m thick PDMS layer. This same PDMS layer was also used to provide the electrical insulation of planar electrodes to carry out capacitively coupled contactless conductivity detection. The analytical performance of the proposed device was shown by using both LIF and capacitively coupled contactless conductivity detection systems. Efficiency around 47 000 plates/m was achieved with good chip-to-chip repeatability and satisfactory long-term stability of EOF. The RSD for the EOF measured in three different devices was ca. 7%. For a chip-to-chip comparison, the RSD values for migration time, electrophoretic current and peak area were below 10%. With the proposed approach, a single chip can be fabricated in less than 30 min including patterning, etching and sealing steps. This fabrication process is faster and easier than the thermal bonding process. Besides, the proposed method does not require high temperatures and provides excellent day-to-day and device-to-device repeatability.
Resumo:
This technical note describes a detailed study on wax printing, a simple and inexpensive method for fabricating microfluidic devices in paper using a commercially available printer and hot plate. The printer prints patterns of solid wax on the surface of the paper, and the hot plate melts the wax so that it penetrates the full thickness of the paper. This process creates complete hydrophobic barriers in paper that define hydrophilic channels, fluid reservoirs, and reaction zones. The design of each device was based on a simple equation that accounts for the spreading of molten wax in paper.
Resumo:
This paper compares the analytical performance of microchannels fabricated in PDMS, glass, and polyester-toner for electrophoretic separations. Glass and PDMS chips were fabricated using well-established photolithographic and replica-molding procedures, respectively. PDMS channels were sealed against three different types of materials: native PDMS, plasma-oxidized PDMS, and glass. Polyester-toner chips were micromachined by a direct-printing process using an office laser printer. All microchannels were fabricated with similar dimensions according to the limitations of the direct-printing process (width/depth 150 mu m/12 mu m). LIF was employed for detection to rule out any losses in separation efficiency due to the detector configuration. Two fluorescent dyes, coumarin and fluorescein, were used as model analytes. Devices were evaluated for the following parameters related to electrophoretic separations: EOF, heat dissipation, injection reproducibility, separation efficiency, and adsorption to channel wall.
Resumo:
While there is research supporting the use of technology in classrooms, there is also evidence that technology often disrupts student learning. Examples of technology use in classrooms by both teachers and students will be explored, including the benefits and risks of each to the learning process. Research findings on cognition, attention, and classroom technologies will inform strategies for best practices for classroom technology use.
Resumo:
The drying process of linseed oil, oxidized at 80 oC, has been investigated with rheology measurements, Fourier transformation infrared spectroscopy (FTIR), and time of flight secondary ion mass spectrometry (ToF-SIMS). The drying process can be divided into three main steps: initiation, propagation and termination. ToF-SIMS spectra show that the oxidation is initiated at the linolenic (three double bonds) and linoleic fatty acids (two double bonds). ToF-SIMS spectra reveal peaks that can be assigned to ketones, alcohols and hydroperoxides. In this article it is shown that FTIR in combination with ToF-SIMS are well suited tools for investigations of various fatty acid components and reaction products of linseed oil.
Resumo:
In this paper we present a framework to be used for evaluation of Information and Communication Technology for Development (ICT4D) projects. The framework is based on Sen´s notion of development as freedom where human capabilities and functionings are seen as key aspects to development. Sen´s capability approach presents an alternative way of seeing and evaluating development (alternative to more traditional ways of measuring development). The approach is based on expanding freedoms, or eliminating unfreedoms, for people so that they can live a life that they have reason to value. Even though Sen is referenced a lot in ICT4D literature the analysis rarely goes further then stating that Sen presents an alternative to traditional ways of development. Reasons can be that the capability approach does not specifically mention technology, in addition to the lack of guidelines presented by Sen on how to use the framework. The aim of this paper is to operationalize the evaluation process and to include a clear role for technology in Sen´s capability framework. The framework is validated with a case on distance education from Bangladesh.
Resumo:
To date there are no analytical techniques designed to exclusively measure bioavailable iron in marine environments. The goal of this research is to develop such a technique by isolating the bioavailable iron using the terrestrial siderophore desferrioxamine B (DFB). This project contained many challenging aspects, but the specific goal of this study was to develop a robust analytical technique for quantification of Fe(III)-DFB complexes at nanomolar concentrations. Past work showed that oxalate (Ox) promotes photodissociation of Fe(III)-DFB to Fe(Il), and we are specifically interested in the mechanism of this process. A model was developed using known thermodynamic constants for Fe(III)-DFB and Fe(III) oxalato complexes and adjusting for ionic strength. The model was confirmed by monitoring the UV-VIS absorbance of the system at a variety of oxalate concentrations and pH. The model did not include ternary complexes. Next., the rate of Fe(1I) production during UV irradiation was examined. The results showed that the rate of Fe(II) production was based entirely on the [Fe(Ox)?]3- speciation, and that reoxidation of Fe(II) occurred via reactive oxygen intermediates. This reoxidation could be avoided by either decreasing the oxygen concentration or by adding a Fe(II) stabilizing reagent, such as ferrozine. Further studies need to be done to confirm that these results apply at sub nanomolar concentrations, and the issue of Fe(II) reoxidation at lower Fe concentrations needs to be addressed.
Resumo:
We employ a moment-based approach to empirically analyse farmer’s decisions about adoption of tube-well technology under depleting groundwater resources using a farm level data from 200 farming households in the Punjab province, Pakistan. The results indicate that the higher the expected profit the greater the probability of adoption. Similarly, with increasing variance the probability of adopting tube-well increases significantly indicating that farmers choose to adopt tube-well technology in order to hedge against production risks. Statistical non-significant the third moment i.e., skewness indicates that farmer generally do not consider downside yield risk when decide to adopt tube-well technology whereas highly significant fourth moment (kurtosis) employ that probability of adoption decreases as a result of extreme events in profit distribution. In addition, we show that land tenureship and three other exogenous variables, i.e., extension services, access to different sources of information and off-farm income play a significant role in the adoption process.
Resumo:
Esta dissertação enfoca o relacionamento entre acumulação de competências tecnológicas e os processos subjacentes de aprendizagem. Este relacionamento é examinado na empresa Invensys Appliance Controls Ltda. - Unidade de Vacaria/RS, durante o período de 1981 a 2000. Trata-se de uma empresa metal-mecânica, fornecedora da indústria de linha branca. Em outras palavras, a dissertação examina as implicações dos processos subjacentes de aprendizagem tecnológica para a acumulação de competências para três funções tecnológicas: processo e organização da produção, produtos e equipamentos. Os processos de aprendizagem são examinados à luz de quatro características: variedade, intensidade, funcionamento e interação, a partir do uso de estruturas de análise existente na literatura. Baseado em estudo de caso individual, este estudo encontrou que a maneira e a velocidade de acumulação de competências tecnológicas na empresa estudada estão associadas aos diversos processos usados para adquirir conhecimento tecnológico e convertê-lo em organizacional. Ademais, a simples incidência desses processos na empresa não garantiu na empresa uma implicação positiva para a acumulação de competências tecnológicas. Através do uso de estrutura existente na literatura, porém aplicada a uma indústria diferente de estudos anteriores, esta dissertação sugere que deve existir um esforço organizado, contínuo e integrado para geração e disseminação de conhecimento em toda a empresa a fim de que a acumulação de capacitação tecnológica seja acelerada na empresa.
Resumo:
This dissertation studies the innovative technological capabilities available in the merger and acquisitions processes and the relationship between these processes with the technological capabilities accumulation to get convergence of technology and services. This study was examined in fourteen companies of the telecommunications industry during 2002 to 2007. Starting on 1990 there were from one end a profusion of studies on the technological capabilities as source of competitive advantages; from another end there are studies on merger and acquisitions with the objective to evaluate the motivations derived from technological factors and stimulation to the competition and the opening of the market. However few of the empirical studies of long stated period that examine the correlation of these events in the industry of telecommunications under the optics of the technological qualification in the level of the companies and for the strategic perspective of enterprise based on the dynamics abilities. An analytical framework already available in the literature was used to describe the contribution of the merger and acquisitions processes for the accumulation of innovative technological capabilities in the studied companies. However the framework was adapted specifically for the industry of Telecommunications. This dissertation also studies the importance of the strategic merger and acquisitions as organizational form in the complementation of technological capability for external sources. Such empirical evidences had been collected from information and data bases published for the own companies who had been examined in this dissertation. Regarding the results, it was found that: 1. In terms of participation with ingress technological capabilities in strategic merger and acquisitions the equipment manufacturers had entered with 71% to 55 of the technological capabilities and the service operator company had entered with 61% to 71 technological capabilities. 2. In terms of implications of the merger and acquisitions for the configuration of resultant technologic capabilities, it was found that the equipment manufacturers had increased 31% the ratio of convergence of technology and the operators of services had increased 4% the ratio for the change in the organizational structure. 3. Regarding the accumulation technological capability to obtain convergence of technology and services was verified the increase these technological capabilities after the merger and acquisitions process in the companies studied. Considering the limitation of this study, the evidences found in this dissertation suggest that the companies use the processes of strategic merger and acquisitions to search for external complementation of their knowledge base to compete in the globalization market. The result demonstrates that this movement has implied in an alteration and accumulation of capability from organization on innovative technological activities regarding the convergence of technology and services.
Resumo:
This dissertation seeks to add new evidence to the international debate on globalization of innovation in the developing countries context. Globalization of innovation, in this dissertation, is defined and measured by the types, levels and rate of innovative technological capability accumulation and the underlying technological learning processes (sources of capabilities) at the firm level in late-industrializing countries ¿ or developing countries. This relationship is examined within a large transnational corporation (TNC) subsidiary of the information and communication technology (ICT) sector in Brasil: Motorola do Brasil during over the period from 1996 to 2006. In the international literature there is a strong debate on the extent to which innovative technological capabilities have been spreading internationally. But, the most of the studies are focused on early industrialized countries. In other words, there is still a scarcity of analysis, mainly at the firm level, from the perspective of developing countries. This dissertation supports itself in analytical basis developed in the international literature on accumulation of technological capabilities and learning in the context of developing countries. The learning processes examined in this dissertation are: (i) intra-firm learning processes; (ii) inter-firm learning processes (links between mother and sister companies); and (iii) links between the firm and other organizations of the innovation system (universities, research institutes, among others). Based on first-hand empirical evidence, qualitative and quantitative, collected on the basis of extensive fieldwork, this dissertation examines these issues with adequate level of detail and depth, in this large company in Brazil. The study results suggest that: Concerning the path of the technological capability accumulation, the firm exhibited heterogeneity in the path of accumulation of technological capabilities to distinct functions. For the functions Software Engineering and Process and Management Project the firm reached the Level 6 (Innovative Intermediate Superior), on a scale that ranges from 1 to 7; In relation to technological capability sources, the firm deliberately sought and built sources of knowledge in order to develop and sustain its innovative technological capabilities. The dissertation, thus, contributes to adding new empirical evidence to the debate on globalization of innovative capabilities from a late-industrializing perspective.
Resumo:
This dissertation seeks to add new evidence to the international debate on globalization of innovation in the developing countries context. Globalization of innovation, in this dissertation, is defined and measured by the types, levels and rate of innovative technological capability accumulation and the underlying technological learning processes (sources of capabilities) at the firm level in late-industrializing countries ¿ or developing countries. This relationship is examined within a large transnational corporation (TNC) subsidiary of the information and communication technology (ICT) sector in Brasil: Motorola do Brasil during over the period from 1996 to 2006. In the international literature there is a strong debate on the extent to which innovative technological capabilities have been spreading internationally. But, the most of the studies are focused on early industrialized countries. In other words, there is still a scarcity of analysis, mainly at the firm level, from the perspective of developing countries. This dissertation supports itself in analytical basis developed in the international literature on accumulation of technological capabilities and learning in the context of developing countries. The learning processes examined in this dissertation are: (i) intra-firm learning processes; (ii) inter-firm learning processes (links between mother and sister companies); and (iii) links between the firm and other organizations of the innovation system (universities, research institutes, among others). Based on first-hand empirical evidence, qualitative and quantitative, collected on the basis of extensive fieldwork, this dissertation examines these issues with adequate level of detail and depth, in this large company in Brazil. The study results suggest that: Concerning the path of the technological capability accumulation, the firm exhibited heterogeneity in the path of accumulation of technological capabilities to distinct functions. For the functions Software Engineering and Process and Management Project the firm reached the Level 6 (Innovative Intermediate Superior), on a scale that ranges from 1 to 7; In relation to technological capability sources, the firm deliberately sought and built sources of knowledge in order to develop and sustain its innovative technological capabilities. The dissertation, thus, contributes to adding new empirical evidence to the debate on globalization of innovative capabilities from a late-industrializing perspective.
Resumo:
Vague words and expressions are present throughout the standards that comprise the accounting and auditing professions. Vagueness is considered to be a significant source of inexactness in many accounting decision problems and many authors have argued that the neglect of this issue may cause accounting information to be less useful. On the other hand, we can assume that the use of vague terms in accounting standards is inherent to principle based standards (different from rule based standards) and that to avoid vague terms, standard setters would have to incur excessive transaction costs. Auditors are required to exercise their own professional judgment throughout the audit process and it has been argued that the inherent vagueness in accounting standards may influence their decision making processes. The main objective of this paper is to analyze the decision making process of auditors and to investigate whether vague accounting standards create a problem for the decision making process of auditors, or lead to a better outcome. This paper makes the argument that vague standards prompt the use of System 2 type processing by auditors, allowing more comprehensive analytical thinking; therefore, reducing the biases associated with System 1 heuristic processing. If our argument is valid, the repercussions of vague accounting standards are not as negative as presented in previous literature, instead they are positive.
Resumo:
Ao longo dos últimos 20 anos tem havido uma profusão de estudos que examinam, no âmbito de empresas, a contribuição dos mecanismos de aprendizagem e da adoção de técnicas de gestão para o processo de acumulação tecnológica. No entanto, ainda são escassos os estudos que examinem, de maneira conjunta e sob uma perspectiva dinâmica, o relacionamento entre a adoção de técnicas de gestão, mecanismos de aprendizagem e trajetórias de acumulação de capacidades tecnológicas. Mais que isto, faltam estudos que examinem o duplo papel das técnicas de gestão, ora como parte do estoque de capacidades tecnológicas, ora como um processo de aprendizagem tecnológica em si. Esta dissertação objetiva oferecer uma contribuição para preencher esta lacuna neste campo de estudo. O enfoque desta dissertação deriva de observações empíricas, realizadas em empresas, e inspira-se no clássico estudo Innovation and Learning: the two faces of R&D, de Cohen e Levinthal (1989). Assim a dissertação baseia-se em um estudo de caso individual, realizado em uma empresa do setor siderúrgico no Brasil, no período de 1984 a 2008, examinando estas questões à luz de modelos analíticos disponíveis na literatura internacional. Neste sentido, adotou-se o entendimento de capacidade tecnológica como o conjunto de recursos necessários para gerar e gerir mudanças tecnológicas, sendo construída e acumulada de forma gradual, a partir do engajamento em processos de aprendizagem e da coordenação de bases de conhecimentos acumulados em diferentes dimensões, simbioticamente relacionadas. As métricas utilizadas identificam tipos e níveis de capacidade tecnológica para diferentes funções e identifica quatro tipos de processos de aprendizagem tecnológica e os avalia em termos de suas características-chave. Tomando-se por base evidências empíricas qualitativas e quantitativas, colhidas em primeira mão, a base de trabalho de campo, este estudo verificou que: 1. A empresa acumulou níveis inovativos de capacidades tecnológicas em todas as funções examinadas, sendo o nível Inovativo Intermediário (Nível 5) nas funções Engenharia de Projetos (de forma incompleta) e Equipamentos e o nível Intermediário Avançado (Nível 6) nas funções Processos e Organização da Produção e Produtos. 2. Os mecanismos de aprendizagem subjacentes à acumulação destes níveis de capacidade tecnológica apresentaram resultados relevantes em termos de suas características-chave, principalmente no que diz respeito à variedade e intensidade: de 24 mecanismos em 1984 para um total de 59 em 2008, com uma variação de 145,8%, e com 56 dos 59 mecanismos (94,92%) utilizados atualmente de forma sistemática. 3. O período compreendido entre os anos de 1990 e 2004, no qual foram implementadas as técnicas de gestão estudadas, exceto o Plano de Sugestões, se caracteriza por apresentar a maior taxa de acumulação de capacidades tecnológicas e por dar início à utilização da quase totalidade dos 35 novos mecanismos de aprendizagem incorporados pela empresa após o início de suas operações (1984). E que as técnicas de gestão estudadas: 1. Colaboraram para o processo de aprendizagem tecnológica da AMBJF, principalmente pela necessidade de se: (i) incorporar novos mecanismos de aprendizagem que lhe permitissem acumular, antecipadamente, a base de conhecimentos necessária à implementação das técnicas de gestão estudadas; (ii) coordenar um número maior de mecanismos que dessem o adequado suporte ao aumento da complexidade de seu Sistema de Gestão Integrada (SOl). 2. Ampliaram, por si, o estoque de capacidades tecnológicas da empresa, maIS especificamente em sua dimensão organizacional, a partir da acumulação de conhecimento em procedimentos, instruções de trabalho, manuais, processos e fluxos de gestão e de produção, dentre outros. Desta forma, os resultados aqui encontrados confirmam que a adoção e a implementação das técnicas de gestão estudadas contribuíram com e influenciaram o processo de aprendizagem tecnológica e a trajetória de acumulação tecnológica da empresa, ao mesmo tempo, exercendo, portanto, um duplo papel na organização. Esta conclusão nos leva a um melhor entendimento do tema e pode contribuir para a compreensão de ações políticas e gerenciais que possam acelerar a acumulação de capacidades tecnológicas, entendendo a relevância das técnicas de gestão menos em termos de sua "mera" adoção e mais do seu processo de implementação.