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71.
In this study the desizing, scouring, bleaching and slack mercerising of cotton fabric by a one–step process at different sodium hydroxide concentrations, impregnation temperatures and curing times were examined. The results indicate that when the fabrics are mercerised at lower temperature, the strength retention and colour strength are enhanced. When the sodium hydroxide concentration is increased, these properties also increase. When cotton fabrics are mercerised for 3 min at 40C and cured for 30 s at 120C, their physical properties are similar to those obtained using a conventional two–step approach. 相似文献
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根据濮城西区沙二上2+3油藏层内矛盾突出的地质特点,提出并实施了远井调剖-近井封口的区块深部调剖试验,并将PI决策技术作为深部调剖选井、选剂、定量以及效果评价的理论基础,现场试验结果表明油藏的均质性明显增强,为厚层非均质油藏进入高含水开发提供了有益的借鉴。 相似文献
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KS Armour BJ Clatworthy AR Bean JE Wells AM Clarke 《Canadian Metallurgical Quarterly》1997,110(1057):462-465
AIMS: To establish trends in frequency of serious spinal cord injuries in rugby and rugby league over a 20 year period and to elucidate patterns of injury from retrospective analysis of cases admitted to New Zealand's two spinal injuries units. METHODS: A detailed survey of unit records with follow-up of selected patients; statistical analysis of data. RESULTS: During the 20 years 1976 to 1995, 119 rugby and 22 rugby league players (total 141) were admitted to New Zealand's two spinal injuries units suffering serious spinal injuries and 47 of these became permanently confined to wheelchairs. There was a steady increase in frequency throughout the period studied. Of the injuries 83% occurred in forwards and 17% in backs. In rugby it was the scrum which produced most injuries, and in rugby league it was the tackle. The early season month of April produced most spinal injuries. In the eighteen months since intense compulsory educational programmes on safety were introduced by the New Zealand Rugby Union there have been no serious spinal cord injuries from rugby scrums. CONCLUSION: Contrary to widespread belief, there has not been a decrease in spinal cord injuries in rugby following rule changes in the mid 1980s. The information produced by this retrospective study has been an effective educational platform to make rugby and rugby league safer. 相似文献
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Walpole J.N. Donnelly J.P. Missaggia L.J. Liau Z.L. Chinn S.R. Groves S.H. Taylor P.J. Wright M.W. 《Photonics Technology Letters, IEEE》2000,12(3):257-259
A Gaussian lateral current-injection profile is approximated by a quasi-random pattern of electrically conducting and insulating regions. This pattern is used for the p-type contact in a laser with a 2.1-mm-long tapered gain region and operating near 1.55-μm wavelength. Lasers with improved stable single lateral modes are obtained with Strehl ratios up to 0.85 for current up to 4.0 A and output power over 1.0 W. Power over 0.5 W can be coupled into a single-mode optical fiber with a cylindrical microlens attached to the output facet to remove the astigmatism of the laser 相似文献
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