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101.
Summary The crystallization and melting behaviour of poly(butylene terephthalate) has been studied in the pure state and in its blends with a polyarylate of bisphenol A and isophthalic/terephthalic acids. Differential scanning calorimetry has been used as experimental technique and the effects of different thermal treatments have been analyzed. Results show the hindrance for the crystallization of poly(butylene terephthalate) imposed by the presence of polyarylate, as well as the existence of multiple melting after isothermal crystallization. Explanations are given for the observed behaviours.  相似文献   
102.
The aim of this paper is to propose new organizational factors that might explain the differences in the extent and the speed of IT adoption. With this in mind, we carried out an analysis of 16 cases in the pharmaceutical distribution sector in Spain. The results indicate that there are certain intangible assets that favour the introduction and development of IT. Among these are a frank and fluid communication between departments and members of the organization, low levels of conflict, the explicit support of top management towards IT adoption and learning and creative skills of IT-staff. In addition to these factors, we found others that we propose as catalysts of IT adoption. Among these we might mention the special relationship between the member-clients and the company in the case of cooperative firms.  相似文献   
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A dozen CuO samples prepared under various conditions and from different starting materials were evaluated as cathode materials for a primary Li/CuO cell. The “thin electrode” method was used for rapid evaluation of the samples. Both coulombic efficiency and discharge voltage depend considerably on the method of synthesis. No correlation was found between the specific surface area and the resistivity of the samples on the one hand and the cathode performance on the other. Best results were obtained from CuO prepared by the oxidation of Cu2O under controlled temperature and time of oxidation.  相似文献   
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The martensitic transformation temperatures and the types of martensitic phases have been determined in a wide concentration range of technological interest for Cu-Al-Ni shape-memory alloys (SMAs) A stability diagram of martensitic phases as a function of alloy concentration has been determined. It is found that when the aluminum content increases, the transformation changes from β 3β3 to β 3γ3, with an intermediate concentration range where both martensites coexist due to a β 3γ3+β3 transformation. On the other hand, an increase of nickel content stabilizes the martensite β3, changing from a mixed β 3γ3 + β3 to a single β 3β3 transformation. Furthermore, linear relationships between M s and Al and Ni concentrations have been obtained for all types of martensitic phases.  相似文献   
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The use of well characterized laboratory animals in biomedical research is of importance for quality securing and reproducibility of animal experiments. Therefore, breeders should not only have in mind the reproduction of their animal stocks, but they should also be interested to achieve an optimal resemblance of the animals in the main traits characterizing them as a model of human diseases. Specific software applications which helps the breeders in monitoring the main breeding parameters, selecting suitable breeding pairs and data processing are practically not available. This prompted us to develop a computer program for management of breeding and experimental data, which we called BB_RADABA. In this report we want to give a short survey on this computer program.  相似文献   
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