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在近几年的农业灌溉工程中,混凝土蓄水池得到了广泛应用。在施工和应用中发现混凝土水池产生的裂缝是很普遍的现象。笔者根据多年的工程经验,分析探讨了混凝土水池出现裂缝产生原因及预防措施。钢筋混凝土水池产生裂缝而发生渗漏是很普遍的现象,本文探讨分析了钢筋混凝土水池常见裂缝的产生原因和预防措施。 相似文献
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In order to improve the quality of Hunyuan inferior Ca-based bentonite (Ca-Bent), semidry process was used to modify Ca-Bent
into superior Na-based bentonite (Na-Bent). The factors affecting sodium-modification were investigated. The optimized experimental
parameters are obtained as follows: Na2CO3 dosage 4.0%, ageing time 25 d, briquetting pressure 25 MPa and briquetting moisture 20%. Under the optimization conditions,
the modified Na-Bent has a colloid value of 73.6 mL/(3g), dilation of 38 mL/g and water absorption in 2 h (2HWA) of 465%,
respectively. The balling results indicate that the modified Na-Bent pellets have higher drop strength and compression strength
than the Ca-Bent pellets. 相似文献
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采用煤基直接还原-磁选工艺对某高铁锰矿进行铁-锰分离的试验研究。不配加添加剂时磁性产物铁品位为59.42%, 锰品位为20.73%; 非磁性产物锰品位为48.88%, 铁品位为5.91%。为强化铁-锰分离, 选择Na2CO3、Na2SO4和Na2S2O3作为添加剂进行还原试验, 结果表明3种添加剂在还原过程中都能促进铁-锰分离, 且Na2S2O3效果最优。在Na2S2O3用量为5%时, 磁性产物的铁品位提高至85.38%, 锰品位降低至9.08%; 非磁性产物的锰品位提高至54.72%, 铁品位降低至2.59%。研究了加入添加剂前后焙烧矿的微观结构和物相转变, 结果表明Na2S2O3有利于MnS和Mn2SiO4的形成并促进了铁晶粒的聚集长大。 相似文献
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The effect of composite agglomeration process (CAP) on fluoric iron concentrates sintering was investigated. The yield and
quality of the sinter are greatly improved when using CAP assisted with heat airflow and enhancing magnesium oxide (MgO) contents.
For conventional sintering of fluoric iron concentrate, due to lower viscosity of binding phase and higher fluidity of liquid
phase, the sinter is formed with large thin-walled holes and the strength of the sinter is deteriorated consequently. The
novel process forms composite agglomerate in which acid pellets are embedded in basic sinter. The pellets are solid with interconnecting
crystals of hematite (Fe2O3) and magnetic (Fe3O4). For basic sintering, after adding MgO, the viscosity of the melting phase increases and the fluidity decreases; and calcium
and aluminum silico-ferrites and magnesium ferrite are formed with perfect crystals and good sintering microstructure. 相似文献
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水利是农业的命脉,在改善农业生产条件、提高农民生活水平、保护生态环境等方面具有不可替代的重要地位和作用。文章探讨了陕县农村小型水利工程的现状、存在的问题及原因,并提出了对策和建议。 相似文献
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在对保定电网110~220 kV输电线路2008-2011年鸟害故障统计分析的基础上,阐述了输电线路鸟害故障发生的规律及形成的原因。在总结多年防治鸟害故障措施优劣的同时,提出了有针对性的防治鸟害故障的组织措施和技术措施。 相似文献