897 resultados para Lead, Jane (Ward), 1623-1704
Resumo:
The thermal transport properties, thermal diffusivity, thermal conductivity and specific heat capacity of Dicalcium Lead Propionate (DLP) crystal have been measured following a modified photopyroelectric thermal wave method. The measurements have been carried out with thermal waves propagating along the three principal symmetry directions, so as to bring out the anisotropy in these parameters. The variations of the above parameters through two prominent phase transition temperatures of this crystal have also been measured to understand the variation of these parameters as it undergoes ferroelectric phase transitions. In addition, complete thermal analysis and FTIR measurements have been done on the crystal to bring out the correlation of these results with the corresponding thermal transport properties. All these results are presented and discussed. The data presented in this paper form a comprehensive set of results on the thermal transport properties of this crystal.
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The work reported in this thesis is the preparation, and the structural, electrical and optical properties of reactively evaporated lead sulphide and tin telluride thin films. The three temperature method had been used for the preparation of these semiconductor thin films. In this preparation technique constituent elements are evaporated from separate sources with the substrate kept at a particular temperature. when one of the constituent element is a gas near room temperature, the method is often called reactive evaporation. It has been found for many materials that a stoichiometric interval exists with a limited range of flux and substrate temperature. Usually this technique is used for the preparation of thin films of high melting point compounds or of materials which decompose during evaporation. Tin telluride and lead sulphide are neither high melting point materials nor do they decompose on melting. But even than reactive evaporation offers the possibility of changing the ratios of the flux of the constituent elements within a wide range and studying its effect on the properties of the films
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The investigation of physical properties of matter has progressed so much during the last hundred years. Today physics is divided in to a large distinct group of special branches. These branches are distinguished by the particular area studied, method of investigation and so on. An independent and important branch that has developed is the physics ofthin films.Any object in solid or liquid form with one of its dimensions very much smaller than that of the other two may be called a thin film. It is having only one common property, namely, one of their dimensions is very small, though all their physical properties may be different. Thin layers of oil, floating on the surface of water, with their fascinating colours, have attracted men’s curiosity from time immemorial. The earliest application of thin films was the protective coatings in the form of paints. A thin layer of tin has been used from ancient times to protect copper utensils from corrosion. Indium thin films are used in certain applications on account of their good lubricating property. Relay contacts are coated with thin films of rare earth metals in order to prevent burning due to arcing. Hard coatings are also available using diamond like carbon (i-carbon). The basic properties of thin films are of considerable interest because of their potential applications in various fields of science and technology
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The research investigations on pollution, particularly in coastal/ estuarine environments are recent ones and started only in 1970s. Hence the informations available are fragmentary and scattered. They throw some light only on either the concentration of heavy metals in water or in sediment or in organisms. No concerted efforts have been made to consolidate and correlate the results between the environment and biota. Literature on the level of concentration of heavy metals in different tissues of organisms with regard to their availability in the living media, their ratio, their inter—relationship, tolerance limit of organisms, etc. are very few or rather nil. in view of the importance enumerated above, the candidate has selected the topic "Effects of some heavy metals copper, zinc and lead on certain tissues of E E (Hamilton and Buchanan) in different environments" for detailed studies and to understand systematically (i) the source of effluents and wastes, (ii) the concentration of heavy metals copper, zinc and lead in water, in sediments and in tissues of the test animal, (iii) their effects, (iv) capacity of tolerance and accumulation in different tissues of the animal, and (V) the "Bioaccumulation Factor", etc.
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Lead free magneto electrics with a strong sub resonant (broad frequency range) magneto electric coupling coefficient (MECC) is the goal of the day which can revolutionise the microelectronics and microelectromechanical systems (MEMS) industry. We report giant resonant MECC in lead free nanograined Barium Titanate–CoFe (Alloy)-Barium Titanate [BTO-CoFe-BTO] sandwiched thin films. The resonant MECC values obtained here are the highest values recorded in thin films/ multilayers. Sub-resonant MECC values are quite comparable to the highest MECC reported in 2-2 layered structures. MECC got enhanced by two orders at a low frequency resonance. The results show the potential of these thin films for transducer, magnetic field assisted energy harvesters, switching devices, and storage applications. Some possible device integration techniques are also discussed
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Most logistics network design models assume exogenous customer demand that is independent of the service time or level. This paper examines the benefits of segmenting demand according to lead-time sensitivity of customers. To capture lead-time sensitivity in the network design model, we use a facility grouping method to ensure that the different demand classes are satisfied on time. In addition, we perform a series of computational experiments to develop a set of managerial insights for the network design decision making process.
Resumo:
A problem in the archaeometric classification of Catalan Renaissance pottery is the fact, that the clay supply of the pottery workshops was centrally organized by guilds, and therefore usually all potters of a single production centre produced chemically similar ceramics. However, analysing the glazes of the ware usually a large number of inclusions in the glaze is found, which reveal technological differences between single workshops. These inclusions have been used by the potters in order to opacify the transparent glaze and to achieve a white background for further decoration. In order to distinguish different technological preparation procedures of the single workshops, at a Scanning Electron Microscope the chemical composition of those inclusions as well as their size in the two-dimensional cut is recorded. Based on the latter, a frequency distribution of the apparent diameters is estimated for each sample and type of inclusion. Following an approach by S.D. Wicksell (1925), it is principally possible to transform the distributions of the apparent 2D-diameters back to those of the true three-dimensional bodies. The applicability of this approach and its practical problems are examined using different ways of kernel density estimation and Monte-Carlo tests of the methodology. Finally, it is tested in how far the obtained frequency distributions can be used to classify the pottery
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The current study arose from previous studies made by McClelland (1972), Namam; Slevin (1993), Kuratko; Hornsby; Naffziger (1997), Hoeltgebaum; Kato (2002); Hoeltgebaum;Debastini (2003), Hoeltgebaum; Santos; Loesch (2003) and Hoeltgebaum; Santos (2003). Its objective is to understand the reasons that that lead an entrepreneur to open his ownbusiness, his degree of satisfaction and to perceive if there is a relation between entrepreneurial motivation and the performance of companies. In order to concretize the objective, a descriptive qualitative/quantitative research was realized, amounting to 88 questions of a closed type, statistically ordered. Data collection was achieved by means of a questionnaire divided into 4 parts. Once responses to the questionnaires were obtained, analysis was performed on them, using LHSTAT software. Among the principal results, it was evident in the analysis of the questionnaires that there were a variety of motivations for opening a new business present among the interviewed, with a small, distinct difference in the frequency of the responses. When the satisfaction of the respondents regarding the performance of the company was analyzed, it was perceived that the greatest satisfaction derived from gross and net profit margin and return on investment. Several interdependencies between motivation and satisfactionand performance were evident in the research, with three in particular being the strongest. It was decided to include a category regarding behavioral characteristics of entrepreneurs tothe objectives of the project in which, according to the interviewees, these have a strong entrepreneurial profile; results showed that all the characteristics are well developed. It wasconcluded that the intrinsic motivations are more evident in the entrepreneurs interviewed and that the greatest satisfaction among them lies in the area of gross and net profit margin andin return over investment. It was perceived that there are clear relationships between the motivation of entrepreneurs and satisfaction with the performance of companies.
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Esta investigación se centra en la Fédération Internationale de Football Association (FIFA) como organización política. Intenta responder dos interrogantes primordiales: 1) ¿cómo la FIFA ha constituido el poder que tiene actualmente y, así, hacerse del monopolio indiscutido del fútbol? Y 2) ¿cómo ha cambiado en el tiempo la política interna de FIFA y su vínculo con la política internacional? Para lograr esto, se realiza un estudio histórico, basado principalmente en documentos, que intenta caracterizar y analizar los cambios de la organización en el tiempo. Se enfatizan las últimas dos presidencias de FIFA, de João Havelange y Joseph Blatter, como casos de estudio.
Resumo:
Se ofrece una clase de ejercicios gimnásticos. La clase esta presentada por Jane Fonda.
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La Bruja Winnie vive en una casa donde todo es negro. Winnie sólo puede ver a su gato negro, Wilbur, cuando sus ojos están abiertos, porque sus ojos son verdes, y por eso, cuando Wilbur los cierra, Winnie siempre cae sobre él, hasta que tiene una brillante idea. La historia utiliza un lenguaje adecuado para niños pequeños. El vocabulario, los temas, y las estructuras que se emplean son las que se encuentran en los dos primeros grados de primaria de inglés. Incluye un diccionario imagen con el vocabulario clave de la historia y cuaderno de actividades.
Resumo:
El profesor Puffendorf es el más grande del mundo científico. Su laboratorio es un lugar lleno de botellas y tubos, máquinas que rechinan, y un viejo armario marcado como, alto secreto donde se encuentran sus secretas pociones que nunca han sido probadas. Un día sale y deja a su asistente y a su mascota. Ahora Enzo tiene la oportunidad tener en sus manos las las pociones. La historia utiliza un lenguaje adecuado para niños pequeños. El vocabulario, los temas, y las estructuras utilizadas son las que se encuentran en los dos primeros grados de primaria de inglés. Incluye un diccionario imagen con el vocabulario clave de la historia y cuaderno de actividades.