O amido termoplástico (TPS) é um material biodegradável que tem sido bastante estudado em função do seu baixo custo e pelo fato de ser derivado de fontes renováveis. Contudo, o TPS apresenta limitações mesmo para aplicação em produtos de baixos requisitos devido a conjunto de fatores como sua baixa propriedade mecânica, térmica, e de resistência à umidade, além de possuir baixa compatibilidade com outros polímeros sintéticos. Nesse trabalho foi testada a modificações do TPS com ácido cítrico e com 4,4-difenil metano diisocianato (MDI) e as blendas desses materiais com polietileno de baixa densidade (PEBD) e o efeito da modificação do PE com anidrido maleico (MA) e da adição de ceras de polietileno não modificada e modificada com anidrido maleico como agente compatibilizante. A modificação do amido com ácido cítrico e com MDI não afetou de forma significativa a sua hidrofilicidade. O uso de MDI se mostrou eficaz na melhoria das propriedades mecânicas do amido não modificado com AC. A compatibilização com cera se mostrou extremamente promissora, tendo no caso da blenda 50/50 de polietileno e TPS compatibilizada com 5 % de cera resultando em um composto com propriedades mecânicas (módulo e resistência à tração) muito similares às do polietileno de origem. / Thermoplastic starch (TPS) is a biodegradable material that has been extensively studied due to its low cost and because it is derived from renewable sources. However, TPS present several drawbacks even for application in products of low performance due to its poor mechanical properties, thermal properties and moisture resistance, and also due to its low compatibility with other synthetic polymers. In this work we studied the modification of TPS with citric acid and with 4,4 \'- diphenyl methane diisocyanate (MDI) and the blends of these materials with low density polyethylene (LDPE) and the effect of modification of PE with maleic anhydride (MA) and the addition of polyethylene waxes unmodified and modified with maleic anhydride as compatibilizing agent. The modification of starch with citric acid and MDI did not affect significantly its hydrophilicity. The use of MDI is effective in improving mechanical properties of unmodified starch with AC. The compatibility with wax showed very promising with the case of blend 50/50 TPS and polyethylene compatibilized with 5% wax results in a material with mechanical properties very similar to those of polyethylene (modulus and tensile strength) .

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<p>Cladophora cellulose polypyrrole composites are recognized as potential biomaterials with future applications in hemodialysis. In this project conductive Cladophora cellulose-polypyrrole (clad-ppy) composites were prepared using two different oxidizing agents: iron (III) chloride and phosphomolybdic acid (PMo). Cyclic voltammetry, conductivity and Specific surface area measurements were done to characterize the synthesized composites. Furthermore in vitro blood compatibility studies were performed. Whole blood was incubated with clad-ppy membranes and then blood was analyzed for platelet number reduction and complement activation products (C3a and sC5b-9). Clad-ppy with Iron (III) chloride membranes were found to be superior in terms of conductivity and surface area while Clad-ppy with PMo membranes were found to provoke less blood activation. The results indicated that each oxidizing agent gave distinct properties to the composite material.</p>

This study investigates the nature of semantic compatibility between constructions and lexical items that occur in them in relation with language use, and the related concept, coercion, based on a usage-based approach to language, in which linguistic knowledge (grammar) is grounded in language use. This study shows that semantic compatibility between linguistic elements is a gradient phenomenon, and that speakers’ knowledge about the degree of semantic compatibility is intimately correlated with language use. To show this, I investigate two constructions of English: the sentential complement construction and the ditransitive construction. I observe speakers’ knowledge of the semantic compatibility between the constructions and lexical items and compared it with empirical data obtained from linguistic corpora and experiments on sentence processing and acceptability judgments. My findings specifically show that the relative semantic compatibility of the lexical items and the construction is significantly correlated with the frequency of use of their co-occurrences and the processing effort and speakers’ acceptability judgments for the co-occurrences. The empirical data show that a lexical item and a construction which are less than fully compatible can be actually used together when the incompatibility is resolved. The resolution of the semantic incompatibility between the lexical item and its host construction has been called coercion. Coercion has been invoked as a theoretical concept without being examined in depth, particularly without regard to language use. By correlating degree of semantic compatibility with empirical data of language use, this study highlights that coercion is an actual psychological process which occurs during the composition of linguistic elements. Moreover, by examining in detail how the semantics of a lexical item and a construction interact in order to reconcile the incompatibility, this study reveals that coercion is semantic integration that involves not only dynamic interaction of linguistic components but also non-linguistic contexts. Investigating semantic compatibility and coercion in detail with empirical data tells about the processes by which speakers compose linguistic elements into larger units. It also supports the assumption of the usage-based model that grammar and usage are not independent, and ultimately sheds light on the dynamic aspect of our linguistic system.

This study investigates the nature of semantic compatibility between constructions and lexical items that occur in them in relation with language use, and the related concept, coercion, based on a usage-based approach to language, in which linguistic knowledge (grammar) is grounded in language use. This study shows that semantic compatibility between linguistic elements is a gradient phenomenon, and that speakers’ knowledge about the degree of semantic compatibility is intimately correlated with language use. To show this, I investigate two constructions of English: the sentential complement construction and the ditransitive construction. I observe speakers’ knowledge of the semantic compatibility between the constructions and lexical items and compared it with empirical data obtained from linguistic corpora and experiments on sentence processing and acceptability judgments. My findings specifically show that the relative semantic compatibility of the lexical items and the construction is significantly correlated with the frequency of use of their co-occurrences and the processing effort and speakers’ acceptability judgments for the co-occurrences. The empirical data show that a lexical item and a construction which are less than fully compatible can be actually used together when the incompatibility is resolved. The resolution of the semantic incompatibility between the lexical item and its host construction has been called coercion. Coercion has been invoked as a theoretical concept without being examined in depth, particularly without regard to language use. By correlating degree of semantic compatibility with empirical data of language use, this study highlights that coercion is an actual psychological process which occurs during the composition of linguistic elements. Moreover, by examining in detail how the semantics of a lexical item and a construction interact in order to reconcile the incompatibility, this study reveals that coercion is semantic integration that involves not only dynamic interaction of linguistic components but also non-linguistic contexts. Investigating semantic compatibility and coercion in detail with empirical data tells about the processes by which speakers compose linguistic elements into larger units. It also supports the assumption of the usage-based model that grammar and usage are not independent, and ultimately sheds light on the dynamic aspect of our linguistic system.

Cladophora cellulose polypyrrole composites are recognized as potential biomaterials with future applications in hemodialysis. In this project conductive Cladophora cellulose-polypyrrole (clad-ppy) composites were prepared using two different oxidizing agents: iron (III) chloride and phosphomolybdic acid (PMo). Cyclic voltammetry, conductivity and Specific surface area measurements were done to characterize the synthesized composites. Furthermore in vitro blood compatibility studies were performed. Whole blood was incubated with clad-ppy membranes and then blood was analyzed for platelet number reduction and complement activation products (C3a and sC5b-9). Clad-ppy with Iron (III) chloride membranes were found to be superior in terms of conductivity and surface area while Clad-ppy with PMo membranes were found to provoke less blood activation. The results indicated that each oxidizing agent gave distinct properties to the composite material.

In the information technology industry which has high network externalities, it is common for a firm to employ new product pre-announcements to promote their future products. However, false product pre-announcements are strategically anti-competitive. Under the two-stage game model, this paper examines the monopolistic firm¡¦s incentive of employing false pre-announcements when competing with a potential rival and whether those pre-announcements are strategically anti-competitive, provided that the market exhibits network externalities and the compatibility of system products is considered. This paper shows that if there are no potential rivals in the future, if the products have network externalities, and if the compatibility of cross-period products is relatively high, then the monopoly will have an incentive to exaggerate the pre-announcements. If potential rivals enter the market at the second stage, then the greater the monopoly¡¦s technological advantage is, the higher the extent of false pre-announcements will be. However, as long as the network effect is large enough, the monopoly is likely to employ pre-announcements, even if the product has no technological advantage. By excluding potential entrants from entering the market, established monopolistic firms keep their profits. And consumers may have false expectation¡Xa firm could win with an inferior technology¡Xwhich will in turn cause unfair competition. In addition, when the differences of the products are getting larger, a firm¡¦s incentive of employing false pre-announcements will raise. When the two products are totally compatible, the monopoly¡¦s new product pre-announcements are merely affected by the technological advantage. Then the greater the monopoly¡¦s technological advantage is, the higher the extent of false pre-announcements will be.

Abstract. The problem of Electromagnetic compatibility is a popular topic. It is divided into two categories, one is conducted electromagnetic interference, another is radiated interference. We can use LISN to measure the signal of conducted electromagnetic interference , and use antenna to measure the signal of radiated interference. This paper will focus on the antenna. The frequency range of radiated Electromagnetic Interference measurement is so wide that using the halfwave dipole antenna will be very time-consuming, Therefore broadband antennas are often used in lieu of the halfwave dipole antennas. The design procedure of the log-periodic dipole array antenna is introduced in this article. Simulation data of such antenna using the NEC2 software, including the input impedance and the antenna pattern are also provided. Furthermore, based on the parameters obtained from the simulation, a log-periodic dipole array antenna can be fabricated. In doing so, the simulation results should be modified to take into considerations of the specification of the material used, such as diameters of the materials, and lengths of the transmission lines. Once the construction of the log-periodic dipole array antenna is completes, it can be compared with the simulation results, and the difference between them should be investigated to find out the optimal design parameters. Finally, the antenna factor can be calculated to compare it with the measurement data.

With the rapid and constant changes taking place in information technology and internet, only firms participating in the creation and utilization of knowledge can hope to obtain the advantageous position in today¡¦s knowledge-based economy. Thus, the issues surrounding knowledge management (KM) have attracted more and more concern from both industry and academia. To add value with KM, we need KMS, which involve the application of IT systems and other organizational resources to manage knowledge strategically, are a relatively recent phenomenon. The goal of this research is to find the significant factors that link with KMS use and individual performance by using diamond model and contingency theory, which emphasizes the importance of fit. We combine with three distinct factors of compatibility, including (1) Technology - Task Compatibility (2) Technology - People Compatibility (3) Technology - Organization Compatibility, to mold an integrated model. An empirical survey methodology is applied to test the research model and seven hypotheses are developed in this study, and then we use PLS to analyze it. The results reveal that Technology-Task compatibility contributes most to the use of KMS. It implies that KMS should fulfill the task needs of users, and therefore, people will use more functions of the KM systems frequently. Besides, Technology-People compatibility has similar effect on the use of KMS. This suggests that it will enhance the usage if the KMS is more compatible with users¡¦ past experience and value. We also found that Technology - Organization compatibility has least impact on usage, but it still needed to take into consideration and worthy to discuss in the future research. In sum, unlike much prior research that has focused on only a limited aspect of compatibility, we provide a more comprehensive conceptual definition that disaggregates the content of compatibility into three distinct and separable constructs and the findings of this study provides some suggestions for the KMS research.

Thesis (Ph. D.)--University of Hong Kong, 1983. / Also availalbe in microfilm.