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statistical mechanics

(Encyclopedia)statistical mechanics, quantitative study of systems consisting of a large number of interacting elements, such as the atoms or molecules of a solid, liquid, or gas, or the individual quanta of light ...

smoke

(Encyclopedia)smoke, visible gaseous product of incomplete combustion. Smoke varies with its source, but it usually comprises hot gas and suspended particles of carbon and tarry substances, or soot. To reduce the a...

noun

(Encyclopedia)noun [Lat.,=name], in English, part of speech of vast semantic range. It can be used to name a person, place, thing, idea, or time. It generally functions as subject, object, or indirect object of the...

associative law

(Encyclopedia)associative law, in mathematics, law holding that for a given operation combining three quantities, two at a time, the initial pairing is arbitrary; e.g., using the operation of addition, the numbers ...

tourniquet

(Encyclopedia)tourniquet to͝orˈnĭkĕt, –kā, tûrˈ– [key], compression device used to cut off the flow of blood to a part of the body, most often an arm or leg. It may be a special surgical instrument, a ru...

virtual observatory

(Encyclopedia)virtual observatory, a collection of integrated astronomical data archives and software tools that utilize computer networks to create an environment in which research can be conducted. Several countr...

flat foot

(Encyclopedia)flat foot, condition of the human foot in which the entire sole rests on the ground when the person is standing. When the foot muscles are weakened or the ligaments are strained and stretched, the arc...

interval

(Encyclopedia)interval, in music, the difference in pitch between two tones. Intervals may be measured acoustically in terms of their vibration numbers. They are more generally named according to the number of step...

irritable bowel syndrome

(Encyclopedia)irritable bowel syndrome (IBS), condition characterized by constipation, diarrhea, or alternating constipation and diarrhea in the absence of any disease process. It is usually accompanied by abdomina...

bronchitis

(Encyclopedia)bronchitis brŏnkīˈtĭs [key], inflammation of the mucous membrane of the bronchial tubes. It can be caused by viral or bacterial infections or by allergic reactions to irritants such as tobacco smo...