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911.
Phosphorus-, zinc-, and chlorine-containing oligomer was used as a comonomer including ionic bonds in its molecules in the synthesis of poly(ethylene terephthalate). Phosphorus-, zinc-, and chlorine-containing poly(ethylene terephthalate) including ionic bonds in its main polymer chain was synthesized. With a content of 0.6% P and 1.25% Zn and 0.1% Cl, the resin has the following characteristics: ηrel = 1.407; COOH 39.90 mg equiv KOH/g 10?6; and mp 255.8°C. The modifier acts as a thermostabilizer. © 1993 John Wiley & Sons, Inc. 相似文献
912.
The unloaded Q -factor of a dielectric resonator is degraded due to conductor loss when it is placed in an MIC environment. The authors report approximate but quite accurate closed form expressions for the Q -factor due to conductor loss. The results obtained are in good agreement with those of rigorous numerical methods. The effect of geometrical parameters on the useful tuning range of the structure is studied. Finally, an explicit relationship between the resonant frequency sensitivity factors and the conductor Q -factor is derived 相似文献
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The results are presented of experimental examination of the effect of the grain size on the spoliation of copper. Levels of the loading pressure, corresponding to various stages of spollation, were determined for two initial states characterized by a mean grain size of 0.29 and 1.62 mm. The results show that for the material with the smaller grain these levels are approximately 0.2 GPa higher than for the material with the larger grain size.Translated from Problemy Prochnosti, No. 2, pp. 73–75, February, 1996. 相似文献
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U. K. Viswanathan T. R. G. Kutty R. Keswani C. Ganguly 《Journal of Materials Science》1996,31(10):2705-2709
The hardening response and the indentation creep of a 350 grade commercial maraging steel were evaluated using a hot hardness tester. The hardness versus temperature plot exhibited three distinct regions. Hardness response was noted between 500–800 K. The unusually high values of activation energy and stress exponent obtained during the creep experiment could be rationalized by a novel concept of introducing a back stress term in the indentation creep relation. The corrected value of the activation energy was found to be reasonably in agreement with the activation energy for diffusion of Ni in iron. Results are supplemented with microstructural observation. 相似文献
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