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以紫色页岩、Ⅱ级粉煤灰为主要成分,掺入适量不同比例的Al203、SiC、NaCl等增强剂和发泡剂,经破碎、混合、粉磨、成球、焙烧、冷却等流程烧制高强陶粒,找出烧制高强紫色页岩陶粒的烧成曲线及适宜的化学成分用量范围. 相似文献
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The microstructure characteristics and meso-defect volume changes of hardened cement paste before and after carbonation were investigated by three-dimensional(3D)X-ray computed tomography(XCT),where three types water-to-cement ratio of 0.53,0.35 and 0.23 were considered.The high-resolution 3D images of microstructure and filtered defects were reconstructed by an XCT VG Studio MAX 2.0 software.The meso-defect volume fractions and size distribution were analyzed based on 3D images through add-on modules of 3D defect analysis.The 3D meso-defects volume fractions before carbonation were 0.79%,0.38% and 0.05% corresponding to w/c ratio=0.53,0.35 and 0.23,respectively.The 3D meso-defects volume fractions after carbonation were 2.44%,0.91% and 0.14% corresponding to w/c ratio=0.53,0.35 and 0.23,respectively.The experimental results suggest that 3D meso-defects volume fractions after carbonation for above three w/c ratio increased significantly.At the same time,meso-cracks distribution of the carbonation shrinkage and gray values changes of the different w/c ratio and carbonation reactions were also investigated. 相似文献
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电子束焊机电子枪阴采用六硼化镧(LaB6)材料制造,与普通高温阴极相比,六硼化镧具有逸出功低,热电子发射密度大的优点,研究了多昌六硼化镧不同纯度、密度、阴极表面粗糙度以及表面污染程度等因素对热电子发射性能的影响。 相似文献
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采用热压成型法制备出碳纳米管环氧树脂复合材料,并对其分散性能和阻尼性能进行了研究。扫描电镜(SEM)分析表明,通过超声振荡处理和分散剂辅助处理可以将碳纳米管较好地分散在环氧树脂基体材料中。采用自由振动对数衰减率法和动态热机械分析仪(DMTAⅤ)对复合材料的阻尼性能进行了测试,结果表明,在环氧树脂基体中加入碳纳米管能够提高复合材料的阻尼性能,并且随着碳纳米管质量分数的增加,复合材料的阻尼性能不断增强,掺加直径为10~20nm的碳纳米管比掺加直径为30~50nm的碳纳米管能更大地提高复合材料的阻尼性能。 相似文献