949 resultados para Piezoelectric buzzer in pulsed operation
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"Sponsored by the Agricultural Research Service, U. S. Department of Agriculture, in co-operation with the state livestock regulatory officials".
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Mode of access: Internet.
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Mode of access: Internet.
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Mode of access: Internet.
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The tricyclic core of vibsanin E was constructed without the use of a protecting group in six steps. The El Gaied Baylis-Hillman variant was key to allowing the Bronsted acid induced tandem cyclization forming rings B and C in one operation.
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A platinum (Pt) on pure ceria (CeO2) supported by carbon black (CB) anode was synthesized using a combined process of precipitation and coimpregnation methods. The electrochemical activity of methanol oxidation reaction on synthesized Pt-CeO2/CB anodes was investigated by cyclic voltammetry and chronoamperometry experimentation. To improve the anode property on Pt-CeO2/CB, the influence of particle morphology and particle size on anode properties was examined. The morphology and particle size of the pure CeO2 particles could be controlled by changing the preparation conditions. The anode properties (i.e., peak current density and onset potential for methanol oxidation) were improved by using nanosize CeO2 particles. This indicates that a larger surface area and higher activity on the surface of CeO2 improve the anode properties. The influence of particle morphology of CeO2 on anode properties was not very large. The onset potential for methanol oxidation reaction on Pt-CeO2/CB, which consisted of CeO2 with a high surface area, was shifted to a lower potential compared with that on the anodes, which consisted of CeO2 with a low surface area. The onset potential on Pt-CeO2/CB at 60 degrees C became similar to that on the commercially available Pt-Ru/carbon anode. We suggest that the rate-determining steps of the methanol oxidation reaction on Pt-CeO2/CB and commercially available Pt-Ru/carbon anodes are different, which accounts for the difference in performance. In the reaction mechanism on Pt-CeO2/CB, we conclude that the released oxygen species from the surface of CeO2 particles contribute to oxidation of adsorbed CO species on the Pt surface. This suggests that the anode performance of the Pt-CeO2/CB anode would lead to improvements in the operation of direct methanol fuel cells at 80 degrees C by the enhancement of diffusion of oxygen species created from the surface of nanosized CeO2 particles. Therefore, we conclude that fabrication of nanosized CeO2 with a high surface area is a key factor for development of a high-quality Pt-CeO2/CB anode in direct methanol fuel cells.
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O principal objetivo deste estudo foi identificar e analisar qual o impacto da tecnologia da informação (TI) na satisfação das pessoas em uma empresa pública. Este estudo pretendeu abordar o assunto de forma a concentrar-se na investigação, com um estudo de caso em uma empresa pública de saneamento ambiental da região do grande ABC paulista, o SEMASA, com o intuito de avaliar as mudanças nas rotinas operacionais dos diversos departamentos da empresa e o impacto causado pela TI na satisfação das pessoas envolvidas. Com base na literatura sobre trabalho e sociedade na era da globalização e empresas públicas, foram analisados inicialmente os motivos que podem contribuir para as pessoas buscarem ingressar na carreira pública. Esse estudo verificou a importância da adoção de ferramentas de tecnologia nos processos produtivos e na prestação de serviços das organizações. Verificou também, que estimular os funcionários de empresas públicas a criarem mecanismos para facilitarem seus trabalhos, através de ferramentas de TI atualizadas, pode ser benéfico, ao mesmo tempo em que pode proporcionar condições destes adquirirem novas capacitações profissionais com a aquisição de novos conhecimentos tecnológicos. Os resultados obtidos apontaram para um significativo aumento na satisfação das pessoas envolvidas sendo estas estimuladas a estarem em constante aperfeiçoamento, através da realização de novos treinamentos e cursos de tecnologia.(AU)
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A fim de retirar a imputação pelo fracasso escolar dos ombros das próprias vítimas (alunos) discutiremos como os críticos do currículo entendem a construção e o funcionamento deste e confrontar com a realidade do alunado, principalmente comparando os resultados conseguidos por estes em provas baseadas no currículo do ensino fundamental e médio. Nossas pesquisas apontam que o fracasso é do currículo, não do aluno, que aplicado com indiferença dentro das escolas, menosprezam a cultura e interesses dos alunos, resultando nas crises de relacionamento e nos baixos resultados de forma geral. Iniciado nas primeiras séries, o currículo irá definir o que a desigualdade social brasileira já definiu, a reprodução das estruturas que formam as elites Isto poderá ser verificado com os resultados das provas do Saresp Sistema de Avaliação de Resultados do Ensino do Estado de São Paulo.(AU)
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Computers have, over the past 10 to 15 years, become an integral part of many activities carried out by British community pharmacists. This thesis employs quantitative and qualitative research methods to explore the use of computers and other forms of information technology (IT) in a number of these activities. Mail questionnaires were used to estimate the level of IT use among British community pharmacists in 1989 and 1990. Comparison of the results suggests that the percentage of community pharmacists using computers and other forms of IT is increasing, and that the range of applications to which pharmacy computers are put is expanding. The use of an electronic, on-line information service, PINS, by community pharmacists was investigated using mail questionnaires. The majority of community pharmacists who subscribed to the service, and who responded to the questionnaire, claimed to use PINS less than they had expected to. In addition, most did not find it user-friendly. A computer program to aid pharmacists when responding to their patients' symptoms was investigated using interviews and direct observation. The aid was not found to help pharmacists in responding to patients' symptoms because of impracticalities involved in its operation. Use of the same computer program by members of the public without the involvement of a pharmacist was also studied. In this setting, the program was favourably accepted by the majority of those who used it. Provision of computer generated information leaflets from pharmacies was investigated using mail questionnaires and interviews. The leaflets were found to be popular with the majority of recipients interviewed. Since starting to give out the leaflets, 27 out of 55 pharmacists who responded to the questionnaire had experienced an increase in the numbers of prescriptions they dispensed. 46 had experienced an increase in the number of patient enquiries they received.
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This thesis examines the present provisions for pre-conception care and the views of the providers of services. Pre-conception care is seen by some clinicians and health educators as a means of making any necessary changes in life style, corrections to imbalances in the nutritional status of the prospective mother (and father) and the assessment of any medical problems, thus maximizing the likelihood of the normal development of the baby. Pre-conception care may be described as a service to bridge the gap between the family planning clinic and the first ante-natal booking appointment. There were three separate foci for the empirical research - the Foresight organisation (a charity which has pioneered pre-conception care in Britain); the pre-conception care clinic at the West London Hospital, Hammersmith; and the West Midlands Regional Health Authority. The six main sources of data were: twenty five clinicians operating Foresight pre-conception clinics, couples attending pre-conception clinics, committee members of the Foresight organisation, staff of the West London Hospital pre-conception clinic, Hammersmith, District Health Education Officers working in the West Midlands Regional Health Authority and the members of the Ante-Natal Care Action Group, a sub-group of the Regional Health Advisory Group on Health Promotion and Preventive Medicine. A range of research methods were adopted. These were as follows: questionnaires and report forms used in co-operation with the Foresight clinicians, interviews, participant observation discussions and informal meetings and, finally, literature and official documentation. The research findings illustrated that pre-conception care services provided at the predominantly private Foresight clinics were of a rather `ad hoc' nature. The type of provision varied considerably and clearly reflected the views held by its providers. The protocol which had been developed to assist in the standardization of results was not followed by the clinicians. The pre-conception service provided at the West London Hospital shared some similarities in its approach with the Foresight provision; a major difference was that it did not advocate the use of routine hair trace metal analysis. Interviews with District Health Education Officers and with members of the Ante Natal Care Action Group revealed a tentative and cautious approach to pre-conception care generally and to the Foresight approach in particular. The thesis concludes with a consideration of the future of pre-conception care and the prospects for the establishment of a comprehensive pre-conception care service.
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This paper studies the characteristics of blends of biodiesel and a new type of SSPO (sewage sludge derived intermediate pyrolysis oil) in various ratios, and evaluates the application of such blends in an unmodified Lister diesel engine. The engine performance and exhaust emissions were investigated and compared to those of diesel and biodiesel. The engine injectors were inspected and tested after the experiment. The SSPO-biodiesel blends were found to have comparable heating values to biodiesel, but relatively high acidity and carbon residue. The diesel engine has operated with a 30/70 SSPO-biodiesel blend and a 50/50 blend for up to 10h and there was no apparent deterioration in operation observed. It is concluded that with 30% SSPO, the engine gives better overall performance and fuel consumption than with 50% SSPO. The exhaust temperatures of 30% SSPO and 50% SSPO are similar, but 30% SSPO gives relatively lower NO emission than 50% SSPO. The CO and smoke emissions are lower with 50% SSPO than with 30% SSPO. The injectors of the engine operated with SSPO blends were found to have heavy carbon deposition and noticeably reduced opening pressure, which may lead to deteriorated engine performance and exhaust emissions in extended operation. © 2013 Elsevier Ltd.
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When comparisons in terms of industrial policy lessons to be learned have taken place, it has tended to be solely vis-a-vis the ‘development state’ East Asian experience. This paper broadens the analysis and considers lessons which African countries can learn from other so-called ‘tiger’ economies including Ireland and the East and South Asian countries. We recognise that the latter are indeed clearly significant as many African countries at the time of independence had economic structures and levels of income quite similar to East Asian countries, yet have grown at vastly different rates since then. Exploring why this has been the case can thus offer important insights into possibilities for industrial policy. Yet this comes with some health warnings over East Asian experience. We suggest that another important contribution can come by looking at the Irish example, given its emphasis on corporatism rather than simply relying on state direction in the operation of industrial policy. The Irish model is also more democratic in some senses and has protected workers’ rights during the development process in contrast to the often highly dirigisite East Asian model. Overall we suggest that some immediate actions are needed, notably with regard to the financial system in small African economies. Without such changes, a poorly functioning financial system will continue to keep investment at low levels. In relation to the small size of the African economies, the paper recommends regional integration and sufficient overseas development assistance (ODA) for infrastructural development. It is also critical to note that the various small African economies each face their own industrial and economic development challenges, and that a ‘one size fits all’ approach is not appropriate; rather the key is to tailor policies and systems to the unique opportunities and development challenges in each African country.
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The system of the automated carrying out of examinations is described. Opportunities of system, its architecture and structure of communications between functional subsystems are resulted. Features of the subsystems making system are described. Types of questions which can be used at carrying out of examination are listed. In the near future the working version of system will be ready to input in commercial operation.
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In a pilot project an optimized mobile latent heat storage based on a system available on the market has been tested at Fraunhofer Institute for Environmental, Safety and Energy Technology. Initially trials were conducted with the aim of optimizing the process of charging and discharging. A specifically constructed test rig at the incineration trials centre at the institute allowed charging and discharging procedures of the mobile latent heat storage with adjustable parameters. In addition an evaluation model was constructed to further optimize the heat exchanger systems. In conclusion the prototype of the mobile latent heat storage was tested in practical operation. The economic and technical feasibility of heat transportation was shown if not utilized waste heat is available. © 2014 The Authors.
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This study investigates the use of Pyroformer intermediate pyrolysis system to produce alternative diesel engines fuels (pyrolysis oil) from various biomass and waste feedstocks and the application of these pyrolysis oils in a diesel engine generating system for Combined Heat and Power (CHP) production. The pyrolysis oils were produced in a pilot-scale (20 kg/h) intermediate pyrolysis system. Comprehensive characterisations, with a view to use as engine fuels, were carried out on the sewage sludge and de-inking sludge derived pyrolysis oils. They were both found to be able to provide sufficient heat for fuelling a diesel engine. The pyrolysis oils also presented poor combustibility and high carbon deposition, but these problems could be mitigated by means of blending the pyrolysis oils with biodiesel (derived from waste cooking oil). The blends of SSPO (sewage sludge pyrolysis oil) and biodiesel (30/70 and 50/50 in volumetric ratios) were tested in a 15 kWe Lister type stationary generating system for up to 10 hours. There was no apparent deterioration observed in engine operation. With 30% SSPO blended into biodiesel, the engine presents better overall performance (electric efficiency), fuel consumption, and overall exhaust emissions than with 50% SSPO blend. An overall system analysis was carried out on a proposed integrated Pyroformer-CHP system. Combined with real experimental results, this was used for evaluating the costs for producing heat and power and char from wood pellets and sewage sludge. It is concluded that the overall system efficiencies for both types of plant can be over 40%; however the integrated CHP system is not economically viable. This is due to extraordinary project capital investment required.