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X-ray crystallography

(Encyclopedia)X-ray crystallography, the study of crystal structures through X-ray diffraction techniques. When an X-ray beam bombards a crystalline lattice in a given orientation, the beam is scattered in a defini...

adenine

(Encyclopedia)adenine ădˈənĭn, –nīn, –nēn [key], organic base of the purine family. Adenine combines with the sugar ribose to form adenosine, which in turn can be bonded with from one to three phosphoric ...

biophysics

(Encyclopedia)biophysics, application of various methods and principles of physical science to the study of biological problems. In physiological biophysics physical mechanisms have been used to explain such biolog...

night blindness

(Encyclopedia)night blindness, inability to see normally in subdued light. It is usually a result of vitamin A deficiency. The rod cells, one of two light-sensitive areas of the retina of the eye, are impaired in t...

Magnus, Heinrich Gustav

(Encyclopedia)Magnus, Heinrich Gustav hīnˈrĭkh go͝osˈtäf mägˈno͝os [key], 1802–70, German chemist, physicist, and educator. In 1831 he became lecturer and in 1834 professor of physics and technology at t...

VX

(Encyclopedia)VX vēˈĕks [key], nerve gas several times more toxic than sarin but less volatile. It kills within minutes if inhaled or deposited on the skin; protection from VX would require both protective suits...

trinitrotoluene

(Encyclopedia)trinitrotoluene or TNT trīˌnīˌtrōtŏlˈyo͞oēn [key], CH3C6H2(NO2)3, crystalline, aromatic compound that melts at 81℃. It is prepared by the nitration of toluene. Trinitrotoluene is a high exp...

potassium nitrate

(Encyclopedia)potassium nitrate, chemical compound, KNO3, occurring as colorless, prismatic crystals or as a white powder; it is found pure in nature as the mineral saltpeter, or niter. (The name saltpeter is also ...

Enceladus

(Encyclopedia)Enceladus ĕnsĕlˈədəs [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn II (or S2), Enceladus is 310 mi (500 km) in diameter, orbits Saturn at a m...

utilitarianism

(Encyclopedia)utilitarianism yo͞oˌtĭlĭtrˈēənĭzəm, yo͞otĭˌ– [key], in ethics, the theory that the rightness or wrongness of an action is determined by its usefulness in bringing about the most happines...