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991.
992.
The free energies of mixing of two networks in the interpenetrating polymer network based on crosslinked polyurethane and poly(ester acrylate) have been determined by the vapour sorption method. It was established that the constituent networks in the IPN are not miscible. The introduction of fillers of different chemical nature increases the compatibility. The thermodynamic affinity of the fillers to the individual networks and IPN was estimated. It was established that when the free energy of interaction of one or both components of the IPN with the filler is negative, reinforcement leads to the formation of a compatible and equilibrium system. For fillers having no affinity to the polymers, compatibilization is observed, which is connected with slowing down of phase separation in the system in the presence of filler. 相似文献
993.
Knee ligamentous injuries occur during sport, and when there is extensive injury, they can be associated with subluxation or dislocation. We present the case of a female basketball player who sustained a knee dislocation during noncontact play. An immediate angiogram confirmed vascular integrity, and surgical treatment with ligamentous reconstruction was performed. Peroneal nerve injury was present but resolved in 42 weeks. A review of the literature discussing knee dislocation is presented. 相似文献
994.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 2, pp. 39–40, February, 1995. 相似文献
995.
996.
S. H. Ahmad 《Polymer International》1992,28(4):291-294
Measurement of the flow stress of high density polyethylene (HDPE) and nylon 66 at strain rates of 103 s?1 using a split Hopkinson pressure bar technique is discussed. The flow stress at a strain of 10% has been determined for both polymers at 20°C. The intrinsic errors involved in this technique are briefly reviewed. The results indicate that the flow stress of HDPE and nylon 66 were 50MPa and 150MPa, respectively, at strain rates of about 103s?1. 相似文献
997.
998.
Semiconducting molybdenum trioxide thin films have been prepared by employing simple and inexpensive spray pyrolysis technique.
Films are found to be polycrystalline in nature with hexagonal phase. Optical band gap energy (direct) and room temperature
electrical resistivity are of the order of 2·9 eV and 108 ohm-cm, respectively. These films exhibit cathodic electrochromism. 相似文献
999.
Crystallite growth characteristics of coprecipitated superfine zirconia powders have been investigated. It was found that the crystallite growth in powders follows a cubic law at 800 and 1000°C; however, the crystallite size data for compacts of both Y-TZP and YSZ cannot be fitted with a traditional parabolic or cubic law, but with a linear relation between crystallite size and the logarithm of time. In addition, it was also found that the degree of agglomeration of the powders can affect the crystallite growth. 相似文献
1000.
Arghavani R. Xia L. M'Saad H. Balseanu M. Karunasiri G. Mascarenhas A. Thompson S.E. 《Electron Device Letters, IEEE》2006,27(2):114-116
This letter discusses a reliable and manufacturable integration technique to induce greater than 1 GPa of stress into a p-channel MOSFET, which will be required to increase the drive current beyond 1 mA//spl mu/m at the sub-90-nm process generation. Uniaxial compressive stress is introduced into the p-channel by both a selective deposition of SiGe in the source/drain and an engineered 2.5-GPa compressively stressed nitride. The highest to date compressively stressed SiN film is obtained by heavy ion bombardment during the deposition of the film. 相似文献