Objective To determine whether the antimicrobial nature of a fatty acid chelate temporary dental cement can be enhanced by the addition of 5% cetyl pyridinium chloride (CPC). Materials and methods The temporary cement, Cavex Temporary was employed, and additions of CPC were made to either the base or the catalyst paste prior to mixing the cement. Release of CPC from set cement specimens was fol...

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, ...

A nondestructive integrated CT-XRD method has been developed and used to study hydrated cement system. In this research, a beam line (BL) at the third-generation synchrotron radiation facility, SPring-8, in Japan, was used. First, X-ray computed tomography (CT) was employed to obtain three-dimensional (3D) images and select a region of interest (ROI) in a given plane section of the hardened cem...

The article presents the results obtained in the course of a study on the use of carbon nanotubes (CNTs) for the modification of a cement matrix. Carbon nanotubes were introduced into a cement paste in the form of an aqueous dispersion in the presence of a surfactant (SDS-sodium dodecyl sulfate), which was sonicated. The selected physical and mechanical parameters were examined, and the correla...

a r t i c l e i n f o Keywords: 1 H NMR (B) Silica fume (D) C–S–H composition (B) Density (B) 1 H NMR has been used to characterise white Portland cement paste incorporating 10 wt.% of silica fume. Samples were measured sealed throughout the hydration without sample drying. Paste compositions and C–S–H characteristics are calculated based on 1 H NMR signal intensities and relaxation analysis. T...

Calcium Silicate Hydrate (C-S-H) is the main hydration product of Portland cement, it has an important impact on the properties of cement and causes a wide range of study. In recent years, superplasticizer, of which the main component is organic macromolecules, has become an important component in preparation for high performance concrete. Molecular dynamics simulation of cement hydration produ...

Capillary porosity percolation in a hydrating cement paste has a large influence on transport properties and durability. Percolation can be examined using low-temperature calorimetry and using microstructure models. In this paper, the two approaches are compared for cement pastes with different water-to-cement ratios and exposed to various curing conditions. The influence of sealed curing is se...

Infrastructure Technology Institute Year 2 Final Report DISCLAIMER The contents of this report reflect the views of the authors, who are responsible for the facts and the accuracy of the information presented herein. This document is disseminated under the sponsorship of the Department of Transportation University Transportation Centers Program, in the interest of information exchange. A study ...

Cement-based materials have complex multi-component, multiscale structures that first form through chemical reaction and then continue to change with time. As with most classes of materials, the porosity of cement paste strongly influences its properties, including strength, shrinkage, creep, permeability and diffusion. Pores in cement paste range in size from nanometers to millimeters, and num...