negative ion


Also found in: Dictionary, Thesaurus, Medical.

Negative ion

An atomic or molecular system with an excess of negative charge. Negative ions, also called anions, are formed in attachment processes in which an additional electron is captured by an atom or molecule. Negative ions were first reported in the early days of mass spectrometry. It was soon learned that even a small concentration of such weakly bound, negatively charged systems had an appreciable effect on the electrical conductivity of gaseous discharges. Negative ions now play a major role in a number of areas of physics and chemistry involving weakly ionized gases and plasmas. Applications include accelerator technology, injection heating of thermonuclear plasmas, material processing, and the development of tailor-made gaseous dielectrics. In nature, negative ions are known to be present in tenuous plasmas such as those found in astrophysical and aeronomical environments. The absorption of radiation by negative hydrogen ions in the solar photosphere, for example, determines the Sun's spectral distribution. See Ion sources

negative ion

[′neg·əd·iv ′ī‚än]
(chemistry)
An atom or group of atoms which by gain of one or more electrons has acquired a negative electric charge.
(physics)
An electron or negatively charged subatomic particle.
References in periodicals archive ?
Electrolytes, which are central to a battery, are salts composed of positive and negative ions.
Negative ions still influenced the cells' response to a given salt, with the effect of the negative ion remaining dependent on the ion's size.
3: MS/MS spectra of metabolite M1 obtained using negative ion electrospray (A) and its proposed decomposition mechanism (B).
Negative ions are fragile fascinating quantum systems having lots of interesting physical and chemical properties.
The negative ion stimulation with the proposed device performed the best in the in-vitro experiment of the three statements.
Beyond the air purifying benefits, consumers can expect to feel more energized and more alert from negative ions disseminated through the newest offering--Ionic Purifiers.
Production and neutralization of negative ions and beams; proceedings.
Negative ion machines supposedly alter the atmospheric electrical charge just as a passing thunderstorm might do.
Purify Your Air Portable air purifiers and negative ion producing devices are highly effective at removing airborne particles like mold, dust, tobacco smoke and pet dander.
5 Ton, Energy Rating : 5 Star Easily Removable Panel, Negative Ion High Eer Rotary, Fresh Air Ventilation Auto Swing, Memory Function
Pulse ion counting detection is common throughout this series for high-sensitivity and fast response times, with choice of positive ion only or combined positive and negative ion detection.
com)-- Fusion IONZ, makers of the popular Fusion IONZ negative ion bracelets recently commissioned a double blind, placebo controlled, board certified clinical trial conducted by the Energy Medicine Research Institute.