共查询到20条相似文献,搜索用时 78 毫秒
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将混合二元酸甲酯化反应液进行衍生处理,考察衍生温度和时间对检测结果的影响,采用气相色谱法-氢火焰离子化检测器(FID)对反应液中多组分进行定量分析。研究表明琥珀酸、戊二酸、己二酸、琥珀酸二甲酯、戊二酸二甲酯、己二酸二甲酯、琥珀酸单甲酯、戊二酸单甲酯和己二酸单甲酯9种成分分别在0. 05%~0. 27%、0. 04%~0. 21%、0. 008%~0. 04%、0. 22%~1. 09%、0. 68%~3. 40%、0. 17%~0. 83%、0. 28%~1. 38%、0. 33%~1. 62%和0. 08%~0. 42%范围内呈良好线性关系(r≥0. 9998),平均回收率良好,可准确判断反应产率,为混合二元酸甲酯化工业稳定生产提供了理论依据和数据支持。 相似文献
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2种生物农药对亚洲玉米螟的杀虫活性 总被引:6,自引:0,他引:6
用Potter喷雾法测定了2种生物杀虫剂阿维菌素和B.t.对亚洲玉米螟3龄幼虫的毒力.结果表明:药后24、48、72 h阿维菌素的LC50值分别为8.23、4.83、4.05 mg/L,B.t.的LC50值分别为4.62 × 106 2.23×106、1.86 ×X 106 IU/L.田间药效试验结果显示:阿维菌素和B.t.制剂对亚洲玉米螟具有良好控制作用,1.8%阿维菌素乳油(16.2 g a.i./hm2)、8000 IU/mg B.t.可湿性粉剂(1.44 × 1010IU a.i./hm2)和2000 IU/mg B.t.颗粒剂(1.44×1010IU a.i./hm2)的防治效果分别为83.24%、86.60%、84.32%,显著优于各药剂较低剂量处理的防治效果. 相似文献
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用后镁碳砖的再生研究 总被引:4,自引:1,他引:3
以用后的废镁碳砖为原料,经过拣选、除渣、破碎、除铁、均化和水化等处理后,制成再生镁碳砖。以97%的用后镁碳砖料再生的镁碳砖的各项性能接近或达到新镁碳砖的水平;以80%的用后镁碳砖料再生的镁碳砖用在300t钢包渣线上,在有20炉次LF处理的情况下,其使用寿命达到82炉次,渣线侵蚀速度为每炉1.28mm。使用结果证明,这种再生镁碳砖达到了同期使用的由电熔镁砂和石墨为原料而生产的新镁碳砖的水平。 相似文献
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LIU Huilin 《中国耐火材料》2008,17(1):26-28
Properties of magnesia-hercynite brick were studied. The coatability, thermal shock resistance, corrosion resistance to cement clinker and thermal conductivity were compared with those of magnesia-chrome brick and magnesia-spinel brick used widely in sintering zone of cement rotary kiln. The result shows that magnesia-hercynite brick is better than magnesia-chrome brick in thermal chock resistance and corrosion resistance to cement clinker, is similar to magnesia-chrome brick and is better than magnesia-spinel brick in coatability and thermal conductivity. 相似文献
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Conclusions Ladle brick with a considerably longer life than conventional chamotte ladle brick is manufactured from Arkalyk rock without clay additions.Checker brick made of high-alumina chamotte and Latnaya clay is recommended for the checker work of regenerators; less melting dust was noted than in chrome-magnesite brick checkers.The basic variety of Arkalyk rock is suitable for the production of chamotte ladle brick without clay additions; the life of this ladle brick is as long as that of conventional brick used at Borovichi Combine. Increased compression would allow the production of higher-strength brick. 相似文献
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H. O. Burrows 《Journal of the American Ceramic Society》1940,23(5):125-133
To study the effect of molten aluminum on refractory brick with a view toward explaining some of the brick failures in aluminum melting furnaces, the following test was conducted. Brick of different compositions and from various manufacturers were placed on end in the bottom of an electrically heated ladle to which molten aluminum was added. After holding the molten aluminum in contact with the brick for thirty-five days, it was poured out and the ladle was allowed to cool slowly to room temperature. A study of the brick revealed that some failed by penetration of the aluminum into the brick accompanied by a reaction between the aluminum and the brick. This penetration was less with the denser brick than with the more porous ones. Of the brick tested, there was the least reaction between aluminum and the chrome brick and most between aluminum and silica brick. Many other factors, however, must be considered when deciding which brick is the most economical to use in aluminum melting. 相似文献
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水泥窑用镁铬砖的残砖中铬含量较高,对环境危害大。为降低铬盐对环境的危害,牡丹江新材料科技股份有限公司在水泥窑上进行了使用低铬砖和无铬砖的试验。试验表明,加锆改性尖晶石砖的使用情况较直接结合镁铬砖差,而加铬方镁石复合尖晶石砖(LYC砖)的使用效果好于直接结合镁铬砖。LYC砖不仅铬含量低,对环境的危害小,且其使用寿命是普通镁铬砖的5倍,是直接结合镁铬砖的1.72倍。使用LYC砖对提高窑运转率,降低生产成本有利。 相似文献
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针对目前我国再生骨料分类标准适用范围窄,难以指导高砖含量再生骨料综合利用的问题,探究了砖含量对再生砖混骨料吸水率、表观密度和压碎指标等方面的影响规律,并结合现有文献资料统计分析,建立了砖含量与吸水率和压碎指标之间的一般线性关系公式。提出将砖含量作为主要分类控制指标,表观密度、吸水率和压碎指标作为技术控制指标的砖混骨料分级分类新方法。这种方法能够有效完善现有技术标准,使之与再生砖混骨料性质相适应,更加有效地指导砖混骨料在混凝土工程中的资源化利用。 相似文献
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A method is presented for the determination of the diffusion coefficient of water in brick. A brick is sealed on five sides to ensure one-dimensional water transport. The wet brick is hung with the utmost ends each from a balance. This way, not only the mass of the water in the brick is measured, but some information is obtained about the mass distribution inside the brick. The brick used in this study appears to be quite inhomogeneous. This is incorporated in the model with an inhomogeneity constant. It needs further research if this parameter depends on the water concentration in the brick. 相似文献
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为取代RH炉用镁铬材料,以电熔镁砂为主原料,分别加入单斜锆、脱硅锆、单斜锆与脱硅锆的混合粉、锆英石制备了ZrO2质量分数分别为15%和20%的镁锆砖,并利用静态坩埚法对比研究了镁锆砖和镁铬砖的抗RH炉渣侵蚀性。结果表明:对于Al2O3含量高且碱度(CaO/SiO2比)大的RH炉渣,镁锆砖抗侵蚀性能优于镁铬砖的;镁锆砖的侵蚀机理是砖中的ZrO2与渣中的CaO迅速反应,形成高熔点物相CaZrO3,能堵塞砖中的孔隙而形成致密保护层,从而阻止钢渣对镁锆砖的进一步侵蚀;而镁铬砖的侵蚀机理是渣中的Al2O3、Fe2O3等R3 和镁铬尖晶石中Cr3 交换,渣与砖反应生成的镁铝尖晶石和镁铁尖晶石使得材料变性,同时由于体积效应使镁铬材料鼓胀开裂,从而导致镁铬砖的严重侵蚀。 相似文献