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951.
Coating with PVD-Techniques This paper deals with the physical vapor deposition processes reviewed by the literature: the coatings, the influence of different parameters on the properties of these coatings, the deposition rates. 相似文献
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Determinations of pH, urea, extractable protein (EP), apparent viscosity (AV), water-binding capacity (WBC), hardness (H), Hunter L, a and b values and sensory evaluation (SE) (raw and cooked), as well as microbiological analysis, were used to study the effects of ice storage on the stability of ray (Raja clavata) muscle. Significant changes were found in pH, bacterial growth and sensory assessment (ammoniacal odour and colour) during the storage period. Urea content, EP, AP, WBC (measured as water loss) and Hunter L value (in cooked muscle) decreased significantly. Statistical analyses did not show significant differences in H and Hunter L value (in raw muscle). The decrease in urea concentration can be described as a linear function of the number of microorganisms suggesting the microbiological character of the process. No dependence was observed between pH or number of microorganisms and EP, whereas AP was much more affected and showed a marked dependence on these two parameters treated independently. The results of this research showed that wings could be stored in ice for 9–10 days without causing important loss of quality. The fish was considered excellent up to day 7 and acceptable after 9 days but unacceptable after 11–12 days onwards. Nonetheless, the shelf-life of the ray in the iced state can vary depending upon the initial state of freshness, handling and the biological conditions of the fish. Microbiological analysis, pH, EP, AV, WBC, SE and Hunter L value have been demonstrated to be factors which could be used to monitor the deterioration of ray during ice storage. 相似文献
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The neuropeptide, galanin, has been implicated in the regulation of rat growth hormone (rGH) release. In the present study, adult male rats were implanted dually with cannulae to the lateral cerebral ventricle and the right atrium. After surgical recovery, rats were infused with M-15, a specific galanin antagonist, into the lateral ventricle. During the course of this brain infusion, rats were subjected to serial blood sampling with red cell and artificial plasma replacement under stress-free conditions. Plasma was saved for rGH assay. Treatment with M-15 reduced rGH pulse amplitude and pulse frequency when compared to vehicle-infused controls. These data suggest that brain galanin participates in the ongoing stimulation of pulsatile rGH release in the adult male rat. 相似文献
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The microstructure of composites made from blends of poly(p-phenylene benzobisthiazole) [PBT] and nylon 6,6 has been investigated with wide-angle X-ray diffraction, selected area electron diffraction, and small-angle X-ray scattering techniques. The composite samples investigated were spun in both fiber and film forms dilute solutions of methane sulfonic acid. The structure of the composites was found to be a microfibrillar network of PBT in a matrix of partially crystalline nylon 6,6. The diameters of the PBT microfibrils were in the range of 30 to 70 Å. 相似文献