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煤炭企业社会责任问题及对策研究 总被引:1,自引:0,他引:1
介绍了企业应承担的社会责任,重点分析了我国煤炭企业在社会责任方面的现状及存在的问题,并提出若干建议。 相似文献
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采用S–N–P阻燃剂通过熔融共混法制备了阻燃聚碳酸酯(PC)材料,通过极限氧指数(LOI)仪、垂直燃烧仪、万能电子试验机、冲击试验机和热重(TG)分析仪分别研究了阻燃PC的阻燃性能、力学性能和热性能。结果表明,S–N–P阻燃剂能显著提高PC的阻燃性能,当其质量分数为0.1%时,阻燃PC的LOI值达到35.5%,与纯PC相比提高了43.15%,能通过UL 94 V–0等级,同时拉伸强度相比纯PC提高了17.35%,弯曲强度提高了36.7%,断裂伸长率提高了121.6%,缺口冲击强度仅降低了7.63%;TG分析表明S–N–P阻燃剂能加速PC降解,从而加速炭层的形成起到阻燃作用。 相似文献
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Based on the principle of ENV 196-4 "Methods of testing cement - Part 4 Quantitative determination of constituents or Chinese Standard GB/12960-2007 Quantitative measurement of mineral admixtures in cement, methods were developed for quantitative determination of fly ash, slag and limestone powder in fresh cement pastes, mortars and concretes. Limestone powder was determined using thermal analysis method. The residue content of fly ash on an 80um sieve, and silt contents of aggregate were also considered during the quantitative determination of mineral composition of quaternary cementitious system. With the developed methods, the deviations between the measured and the actual mineral contents of the constituent in the eemantitious material in fresh cement paste, mortar and concrete, were within 3%. 相似文献
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