Two studies identify new strategies for insect control

Mosquitoes spread several diseases, among them malaria and dengue virus. In 2020, about 241 million cases of malaria occurred worldwide, with a few more million cases occurring in 2021. Nearly half the world's population ...

A light-powered catalyst could be key for hydrogen economy

Rice University researchers have engineered a key light-activated nanomaterial for the hydrogen economy. Using only inexpensive raw materials, a team from Rice's Laboratory for Nanophotonics, Syzygy Plasmonics Inc. and Princeton ...

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Ammonia is a compound of nitrogen and hydrogen with the formula NH3. It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or indirectly, is also a building-block for the synthesis of many pharmaceuticals. Although in wide use, ammonia is both caustic and hazardous. In 2006, worldwide production was estimated at 146.5 million tonnes. It is used in commercial cleaning products.

Ammonia, as used commercially, is often called anhydrous ammonia. This term emphasizes the absence of water in the material. Because NH3 boils at -33.34 °C (-28.012 °F) at a pressure of 1 atmosphere, the liquid must be stored under high pressure or at low temperature. Its heat of vapourization is sufficiently high so that NH3 can be readily handled in ordinary beakers, in a fume hood (i.e., if it is already a liquid it will not boil readily). "Household ammonia" or "ammonium hydroxide" is a solution of NH3 in water. The concentration of such solutions is measured in units of baume (density), with 26 degrees baume (about 30% w/w ammonia at 15.5 °C) being the typical high concentration commercial product. Household ammonia ranges in concentration from 5 to 10 weight percent ammonia.

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