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1. Biomineralization in cement and concrete research

   https://doi.org/10.21809/rilemtechlett.2023.187  

   Dowdy, Nicolas; Srubar, Wil (July 2023, RILEM Technical Letters)

   Biomineralization refers to the biological processes through which living organisms produce minerals. In recent years, biomineralizing microorganisms have been used to stabilize soil or to impart a self-healing or self-sealing mechanism to damaged cement and concrete materials. However, applications of biominerals in cement and concrete research can extend far beyond these applications. This article focuses on the biomineralization of calcium carbonate (CaCO3) and silicon dioxide (SiO2) and their past, present, and future potential applications in cement and concrete research. First, we review the mechanisms of CaCO3 and SiO2 biomineralization and the micro- and macroorganisms involved in their production. Second, we showcase the wide array of biomineral architectures, with an explicit focus on CaCO3 polymorphs and SiO2 morphologies found in nature. Third, we briefly summarize previous applications of CaCO3 and SiO2 biomineralization in cement and concrete research. Finally, we discuss emerging applications of biominerals in cement and concrete research, including mineral admixtures or raw meal for portland cement production, as well as other applications that extend beyond self-healing. 

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2. Investigation Methods for Characterizing Nanoparticles in Concrete

   https://doi.org/10.14359/51720214  

   Hendrix, Douglas; Bassim, Nabil; Wille, Kay (January 2019, American Concrete Institute)
3. Making Abstraction Concrete in the Elementary Classroom

   https://doi.org/10.1145/3626252.3630890  

   Hung, Eping E; Vanderberg, Maggie; Krause, Gladys; Skuratowicz, Eva (March 2024, ACM)
4. Copper Corrosion Behavior in Simulated Concrete-Pore Solutions

   https://doi.org/10.3390/met10040474  

   Bacelis, Ángel; Veleva, Lucien; Alpuche-Avilés, Mario A. (April 2020, Metals)

   null (Ed.)

   The copper corrosion was studied for 30 days in two alkaline electrolytes: saturated Ca(OH)2 and cement extract, employed to simulate concrete-pore environments. Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry were carried out at the open circuit potential (OCP), and potentiodynamic polarization (PDP) curves were performed for comparative purposes. Electrochemical current fluctuations, considered as electrochemical noise (EN), were employed as non-destructive methods. The tests revealed that sat. Ca(OH)2 is the less aggressive to the Cu surface, mainly because of the lower in one order pH. In consequence, the OCP values of Cu were more positive, the polarization resistance values were higher by one order of magnitude, and the anodic currents of Cu were lower than those in the cement extract. The analyzed EN indicated that the initial corrosion attacks on the Cu surface are quasi-uniform, resulting from the stationary persistent corrosion process occurring in both model solutions. XPS analysis and X-ray diffraction (XRD) patterns revealed that in sat. Ca(OH)2, a Cu2O/CuO corrosion layer was formed, which effectively protects the metallic Cu-surface. We present evidence for the sequential oxidation of Cu to the (+1) and (+2) species, its impact on the corrosion layer, and also its protective properties. 

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5. Durability of GFRP reinforcing bars in seawater concrete

   https://doi.org/10.1016/j.conbuildmat.2020.121492  

   Morales, Carlos N.; Claure, Guillermo; Emparanza, Alvaro Ruiz; Nanni, Antonio (February 2021, Construction and Building Materials)

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