This study investigated the basic mechanical and microscopic properties of cement produced with metakaolin and quantified the production of residual white efflorescence. Cement mortar was produced at various replacement ratios of metakaolin (0, 5, 10, 15, 20, and 25% by weight of cement) and exposed to various environments. Compressive strength and efflorescence quantify (using Matrix Laborator...

introduction: candida albicans (ca) is by far the most common yeast of oral infections, including endodontic infections. the aim of this study was to evaluate and compare the antifungal effect of white-colored mineral trioxide aggregate (wmta) and portland cement (pc) using a tube-dilution test. materials and methods: wmta and pc were tested freshly mixed and after 24 h. the experiment was perf...

The development of the mesoscopic material structure during the hydration of ordinary Portland cement paste is studied by small-angle neutron scattering. Results on the time dependence of radii of gyration (Guinier region) and exponents (Porod region) are given and discussed. Introduction Building materials like hardened cement are heterogeneous. Their useful properties (as strength, porosity, ...

Calcium silicate hydrate (CSH) is the major volume phase in the matrix of Portland cement concrete. Total x-ray scattering measurements with synchrotron x rays on synthetic CSH(I) shows nanocrystalline ordering with a particle diameter of 3.5(5) nm, similar to a size-broadened 1.1 nm tobermorite crystal structure. The CSH component in hydrated tricalcium silicate is found to be similar to CSH(I...

whose suggestions got this paper off the ground and gave it direction. The paper has also benefitted from comments from The contributions of innovations, factor endowments and institutions to American industrialisation are examined through analysing the rise of the American portland cement industry. Minerals abundance contributed in multiple ways to the spectacular rise during the 1890s. Howeve...

Small-angle neutron scattering was used to measure the effect of water-to-cement ratio (w/c) and cement batch variation on the surface area of ordinary Portland cement (OPC) paste after hydration for 28 days at room temperature, and to measure the development of surface area over the first three days of hydration at 30 ̊C. The 28 day surface area was found to increase with w/c ratio in proportio...

Attack of Portland cement by ambient sulfates presents a considerable risk to structures in some environments. In this study, x-ray microtomography, a high resolution variant of medical “CT”, noninvasively mapped the progression of damage in Portland cement resulting from exposure to an aqueous solution of Na2SO4 (sodium ion concentration of 10,000 ppm). Cement paste samples from water-to-cemen...