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boil

(Encyclopedia)boil or furuncle fyo͝orˈŭngkəl [key], tender, painful inflammatory nodule in the skin, which becomes pustular but with a hard center (see abscess). It may be caused by any of various microbes, the...

lock and key

(Encyclopedia)lock and key, fastening fitted to an entryway, such as a gate or door, or a container, such as a cabinet, drawer or safe, to keep it closed and/or prevent unauthorized access or use. Locks typically c...

Kant, Immanuel

(Encyclopedia)Kant, Immanuel ĭmänˈo͞oĕl känt [key], 1724–1804, German metaphysician, one of the greatest figures in philosophy, b. Königsberg (now Kaliningrad, Russia). The impact of Kant's work has be...

low-temperature physics

(Encyclopedia)low-temperature physics, science concerned with the production and maintenance of temperatures much below normal, down to almost absolute zero, and with various phenomena that occur only at such tempe...

molecular weight

(Encyclopedia)molecular weight, weight of a molecule of a substance expressed in atomic mass units (amu). The molecular weight may be calculated from the molecular formula of the substance; it is the sum of the ato...

polarization of light

(Encyclopedia)polarization of light, orientation of the vibration pattern of light waves in a singular plane. Unpolarized light can be converted into a single polarized beam by means of the Nicol prism, a device ...

insulin

(Encyclopedia)insulin, hormone secreted by the β cells of the islets of Langerhans, specific groups of cells in the pancreas. Insufficiency of insulin in the body results in diabetes. Insulin was one of the first ...

photographic processing

(Encyclopedia)photographic processing, set of procedures by which the latent, or invisible, image produced when a photographic film is exposed to light is made into a permanent visible image. The negative may b...

water supply

(Encyclopedia)water supply, process or activity by which water is provided for some use, e.g., to a home, factory, or business. The term may also refer to the supply of water provided in this way. In the United Sta...

noumenon

(Encyclopedia)noumenon no͞oˈmənŏnˌ [key], in the philosophical system of Immanuel Kant, a “thing-in-itself”; it is opposed to phenomenon, the thing that appears to us. Noumena are the basic realities behin...