Mechanism of Microbially Induced Calcite Precipitation in Self-healing Concrete
Mechanism of Microbially Induced Calcite Precipitation in Self-healing Concrete
复制标题
自修复混凝土中微生物诱导方解石沉淀的机理
DOI：
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发表时间：
2013
期刊：
影响因子：
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通讯作者：
Li, Ruiyang
中科院分区：
文献类型：
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作者：
Qian, Chunxiang;Luo, Mian;Pan, Qingfeng;Li, Ruiyang
通过控制矿化产物、pH值、O2和底物等条件，研究了微生物诱导方解石沉淀的过程，结果表明：微生物诱导的方解石沉淀为方解石晶体，矿化过程需要O2;随着细菌的生长，菌液的pH值从7.0逐渐升高到8.3，在细菌矿化过程中起着重要的作用。方解石的形成是细菌代谢转化的结果，而不是在胞外酶的作用下直接分解底物。代谢过程产生CO2，底物提供Ca 2+和CO 32-，结果表明，细菌的生长创造了碱性环境，通过各种生理活动产生CO2，细菌细胞壁带负电荷，在碱性环境中，生成的CO2分子与Ca ~（2+）反应生成方解石晶体。
The process of microbially induced calcite precipitation was investigated via the control of mineralization production,pH value,O2and substrate,respectively.The experimental results show that the mineral precipitation induced by bacteria is calcite crystal,and the mineralization process needs O2.The pH value of bacteria liquid increased from 7.0 to 8.3 gradually when the bacteria grew,which plays an important role in the bacteria mineralization process.Calcite was formed due to the bacterial metabolic conversions rather than the direct decomposition of substrate under the action of extracellular enzymes.The metabolic process produced CO2,the substrate provided Ca2+ and CO32–,and other organic nutrients could also provide CO32–.The possible mechanism of bacterial induced mineral precipitation was analyzed.The results show that the growth of bacteria creates an alkaline environment and produces CO2 through various physiological activities.The cell wall of bacteria was negatively charged,affecting calcium carbonate precipitation by acting as sites of nucleation or calcium enrichment.The produced CO2 molecules reacted with Ca2+to form calcite crystal in alkaline environment.