The in vivo disintegration of luting cements was determined at 6- and 12-month intervals in two test series of 20 participants each. Four cements were inserted in the wells located in the mesial and distal surfaces of cast crowns. Glass ionomer, silicophosphate, polycarboxylate, and zinc phosphate cements prepared with recommended powder/liquid ratios are discussed, and are ranked with respect ...

In this work, we studied the effect of carboxylic acid on the rheological properties of a high-alumina cement mortar (CH45) produced by the Algerian firm REFRACTAL.The investigated properties are setting time, water consumption, electrical conductivity, pH, density and the compressive strength. The results show a setting time of about 200 min for the acid...

Many concrete structures are required to have sufficient abrasion resistance, such as dams, canals, roads and floors. The abrasion resistance of concrete may be defined as its ability to resist being worn away by rubbing. Compressive strength and aggregate type are also important factors affecting the abrasive behaviour of concrete. However, very little information on the properties of haematit...

The construction industry is growing fast alongside the growth of economy and population. As one major building materials, brick in high demand for purposes. continuous will eventually lead to a shortage raw materials long run, such as sand Ordinary Portland cement. This issue could be resolved by utilizing waste Expanded Polystyrene (EPS) beads Silica Fume (SF), replacement cement production b...

Concrete is the most widely used building material. Numerous varieties of concrete are available. They resolved by formation binders and types aggregate to suit application engineered The quality based on specific proportions different materials added it such cement, slag, ash, water, superplasticizer, coarse fine aggregate. compressive strength hangs many factors as water-cement ratio, cement ...

Dosima fascicularis is the only barnacle which can drift autonomously at the water surface with a foam-like cement float. The cement secreted by the animal contains numerous gas-filled cells of different size. When several individuals share one float, their size and not their number is crucial for the production of both volume and mass of the float. The gas content within the cells of the foam ...

The paper presents the results of casting and testing of 264 GFRC specimens. The glass fibers were 25 mm long, with the aspect ratio (L/D) ranging between 1250 and 3570. The parameters studied were the ratio (by weight) of fibers to cement, i.e. F/C=0%, 1.5%, 3%, and 4.5%, and the ratio of coarse to fine aggregates (gravel to sand), i.e. G/S=1.1, 0.7 and 0.2. In total, 12 mix designs were selec...

Background: Cement production is associated with heavy metal emissions and environmental pollution by cement dust. The degree of contamination of drinking water sources by major and trace elements present in cement dust generated by united cement factory (UNICEM) is still uncertain. This study estimated the element content of ground and surface water samples (hand-dug wells, boreholes and strea...