Aluminosilicate refractories are manufactured using refractory clays, sillimanite minerals, bauxite, and mixtures of alumina and silica sand. They will refer, somewhat arbitrarily, to common crystalline compounds with melting temperatures of at least 1500 °C .
A casting defect is an undesired irregularity in a metal casting process. Some defects can be tolerated while others can be repaired, otherwise they must be eliminated. They are broken down into five main categories: gas porosity, shrinkage defects, mold material defects, pouring metal defects, and metallurgical defects.
The first step in making paint involves mixing the pigment with resin, solvents, and additives to form a paste. If the paint is to be for industrial use, it usually is then routed into a sand mill, a large cylinder that agitates tiny particles of sand or silica to grind the pigment particles, making them smaller and dispersing them throughout ...
Fossils. The term "fossil" is used for any trace of past life.Fossils are not only the actual remains of organisms, such as teeth, bones, shell, and leaves (body fossils), but also the results of their activity, such as burrows and foot prints (trace fossils), and organic compounds they produce by biochemical processes (chemical fossils).
The alkali–silica reaction (ASR), more commonly known as "concrete cancer", is a swelling reaction that occurs over time in concrete between the highly alkaline cement paste and the reactive non-crystalline silica found in many common aggregates, given sufficient moisture.