from The American Heritage® Dictionary of the English Language, 4th Edition
- n. A white or colorless crystalline compound, SiO2, occurring abundantly as quartz, sand, flint, agate, and many other minerals and used to manufacture a wide variety of materials, especially glass and concrete.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Silicon dioxide.
- n. Any of the silica group of the silicate minerals.
from the GNU version of the Collaborative International Dictionary of English
- n. Silicon dioxide, SiO�. It constitutes ordinary quartz (also opal and tridymite), and is artifically prepared as a very fine, white, tasteless, inodorous powder.
from The Century Dictionary and Cyclopedia
- n. Silicon dioxid (SiO2), or silicic anhydrid, a white or colorless substance, nearly insoluble in water and in all acids except hydrofluoric acid.
- n. Silica fused by the oxyhydrogen blowpipe may be worked in the plastic state, very much as glass is, and retains its amorphous character on cooling. Extremely delicate threads of this material may be drawn, and are used to suspend minute, readily mobile mirrors or other such parts of physical apparatus; they are also valuable as electrical insulators, being less affected by atmospheric moisture than threads of glass. Tubes, flasks, and beakers of moderate size have also been made from fused silica, and are useful on account of the hardness of the material, the high temperature it will bear without melting, the rapid changes of temperature it will sustain without cracking, and its superior resistance to most chemical reagents. Its behavior as respects dilatation by heat is also important. Berthelot has, however, recently shown that it is permeable by gases, particularly at high temperatures.
- n. Same as siliqua, 6.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- n. a white or colorless vitreous insoluble solid (SiO2); various forms occur widely in the earth's crust as quartz or cristobalite or tridymite or lechatelierite
Grasses have a gritty compound called silica, which is contained in sand and is used to make glass.
And not too surprisingly (since silica is the most abundant mineral in the Earth’s crust), the coating is non-toxic and environmentally harmless.
It is from the silicone family, which originates from silica, which is found in granite, quartz and sand.
The ash also in high in silica, which is extremely abrasive, and can lead to excessive wear on the animals 'tooth enamel.
Aerogels can be made out of many different substances, including silicon dioxide (also called silica), carbon and even egg albumen, though silica aerogels are among the most common.
Many pastes also contain silica, which is a drying agent.
And it's really silica, which is glass that has melted, then when it's magma inside the volcano, forms solid.
Long used by herbal healers in Europe and China, horsetail—also known as silica—is rich in nutrients, including silicon.
Cheng, who has developed a type of silica polymer called silica sol, says that it has many nanopores that help it trap the pigment of the photocromatic dye.
CHAIKIN: The tiles are made of silica, which is pretty much the same as beach sand, only it's processed in such a way as to be extremely pure and it has the property of being extremely heat resistant.