field
field in physics, region throughout which a force may be exerted; examples are the gravitational, electric, and magnetic fields that surround, respectively, masses, electric charges, and magnets. The field concept was developed by M. Faraday based on his investigation of the lines of force that appear to leave and return to a magnet at its poles (see flux, magnetic ). Fields are used to describe all cases where two bodies separated in space exert a force on each other. The alternative to postulating a field is to assume that physical influences can be transmitted through empty space without any material or physical agency. Such action-at-a-distance, especially if it occurs instantaneously, violates both common sense and certain modern theories, notably relativity , which posits that nothing can travel faster than light. In a field description, rather than body A directly exerting a force on body B, body A (the source) creates a field in every direction around it and body B (the detector) experiences the field that exists at its position. If a change occurs at the source, its effect propagates outward through the field at a constant speed and is felt at the detector only after a certain delay in time. The field is thus a kind of "middleman" for transmitting forces. Each type of force (electric, magnetic, nuclear, or gravitational) has its own appropriate field; a body experiences the force due to a given field only if the body itself it also a source of that kind of field. The reciprocity implied by Newton's third law of motion (equal action and reaction) is thus preserved. If two bodies exert a mutual force, they possess potential energy that depends on their relative positions; it is natural to regard this energy as residing in the field the bodies create.
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denaturation
Book article from: The Columbia Encyclopedia, Sixth Edition
denaturation term used to describe the loss of native...the precise geometry is said to cause denaturation. Extensive unfolding sometimes causes...precipitation of the protein from solution. Denaturation is defined as a major change from the...
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Denaturation
Book article from: Chemistry: Foundations and Applications
Denaturation Protein molecules carry out many important...functionality and is said to have undergone denaturation. The interactions, such as hydrogen...A familiar example of heat-caused denaturation are the changes observed in the albumin...
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denaturation, protein
Book article from: A Dictionary of Food and Nutrition
denaturation, protein A change in the structure of protein by heat, acid, alkali, or other agents which results in loss of solubility and...
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thermal denaturation
Book article from: A Dictionary of Biology
thermal denaturation See denature .
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denature
Book article from: A Dictionary of Biology
...loss of its biological properties. Denaturation involves unfolding of the polypeptide...structure; it is caused by heat ( thermal denaturation ), chemicals, and extremes of pH...boiled eggs are largely a result of denaturation. Compare renaturation .
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