摘要
选取一种碳酸盐矿化菌,利用其新陈代谢过程中发生的酶化反应分解底物生成CO23–,通过适时引入Ca2+,最终在水泥石表面沉积一层致密而坚硬的碳酸钙保护层。研究了不同生长阶段的细菌和Ca2+浓度对所得碳酸钙层的物理、化学性能的影响,并通过测试毛细吸水系数表征试样表面覆膜后的抗渗效果。结果表明:细菌活性和Ca2+浓度对所沉积的碳酸钙的晶型和形貌均有很大程度的影响;经过菌液浸泡法表面覆膜的水泥石试样,其表面吸水系数大大降低,抗渗性能得到有效改善。
Bacterially induced calcium carbonate precipitation was used as a novel and environmentally friendly approach to produce a protective layer on the surface of cement-based materials in the study. The physical and chemical properties of the obtained layers were examined. The composition of the deposited layers was characterized by X-ray diffraction analysis and the morphology of the particles was displayed by scanning electron microscopy. The results show that bacterial activity has a profound effect on the properties of the calcium carbonate layers. A capillary water absorption test was carried out to evaluate the ability of the protective layers. Experimental results indicate that the calcium carbonate layer, obtained under the conditions of a high bacterial activity and an appropilate concentration of Ca^2＋ can greatly improve the water penetration resistance of the specimen surfaces. This type of treatment has the potential to conserve and consolidate cement-based materials.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2009年第7期1097-1102,共6页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(50578035)资助项目
关键词
细菌活性
酶化作用
浸泡法
碳酸钙层
吸水系数
bacterial activity
enzyme digestion
immersing method
calcium carbonate layer
water absorption coefficient
