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chloropicrin

(Encyclopedia)chloropicrin klōrˌəpĭkˈrĭn [key], colorless oily liquid used as a poison gas. It is a powerful irritant, causing lachrymation, vomiting, bronchitis, and pulmonary edema; lung injury from chlorop...

antidiuretic hormone

(Encyclopedia)antidiuretic hormone ănˌtēdīyo͞orĕtˈĭk [key], polypeptide hormone secreted by the posterior pituitary gland. Its principal action is to regulate the amount of water excreted by the kidneys. An...

fusion

(Encyclopedia)fusion, in physics. 1 The change of a substance from the solid to the liquid state, also known as melting. The heat given up by a unit mass of a substance during fusion is called the latent heat of fu...

acetaldehyde

(Encyclopedia)acetaldehyde ĕthˈənălˌ [key], CH3CHO, colorless liquid aldehyde, sometimes simply called aldehyde. It melts at −123℃, boils at 20.8℃, and is soluble in water and ethanol. It is formed by th...

precipitation, in chemistry

(Encyclopedia)precipitation, in chemistry, a process in which a solid is separated from a suspension, sol, or solution. In a suspension such as sand in water the solid spontaneously precipitates (settles out) on st...

turpentine

(Encyclopedia)turpentine, yellow to brown semifluid oleoresin exuded from the sapwood of pines, firs, and other conifers. It is made up of two principal components, an essential oil and a type of resin that is call...

spinal puncture

(Encyclopedia)spinal puncture, surgical penetration of the spinal canal by a hollow needle introduced between two of the lumbar vertebrae. The arrangement permits injection of antibiotics or anesthetics (see anesth...

fats and oils

(Encyclopedia)fats and oils, group of organic substances that form an important part of the diet and also are useful in many industries. The fats are usually solid, the oils generally liquid at ordinary room temper...

milk, food

(Encyclopedia)milk, liquid secreted by the mammary glands of female mammals as food for their young. The milk of the cow is most widely used by humans, but the milk of the mare, goat, ewe, buffalo, camel, ass, zebr...

rocket, in aeronautics

(Encyclopedia)CE5 Relative positions of the components of the Saturn V rocket, the U.S. space vehicle used in the moon missions rocket, any vehicle propelled by ejection of the gases produced by combustion of s...