electro-, electr-, electri-

(Greek > Latin: electric, electricity; from amber, resembling amber, generated from amber which when rubbed vigorously [as by friction], produced the effect of static electricity)

Electronics in our lives consists of numerous tools

Equipment which we use everyday relies on electronics to function including calculators, car controls, cameras, washing machines, medical scanners, mobile telephones, radar systems, computers; as well as many other applications or devices which are listed in this unit.

electron metallography
The study of the microscopic structure of metals using an electron microscope.
electron metallurgy
A branch of metallurgy which uses electron microscopic techniques in the examination of the nature of metals.
electron micrograph
1. A reproduction of an image formed by the action on an electron beam on a photographic emulsion.
2. A photograph or other reproduction of an image formed by the action of an electron beam by an electron microscope.
electron micrography
The photographic recording of images produced by the electrons from an electron microscope.

The electron beam carries the images through an array of lenses and an enlarged electron image is used to stimulate a fluorescent screen that is photographed by a camera system.

electron microprobe, electron probe
1. An instrument which focuses an accelerated beam of electrons to an extremely small point on the surface of a crystal specimen so it can be studied by the effects of the electron beam.
2. An X-ray machine in which electrons transmitted from a hot-filament source are accelerated electrostatically, then focused to an extremely small point on the surface of a specimen by an electromagnetic lens.

A nondestructive analysis of the specimen can then be made by measuring the back-scattered electrons, the specimen current, the resulting X-radiation, or any other resulting process.

3. A technique of analysis using the electron microscope based on spectral analysis of the scattered X-ray emission from the specimen induced by the electron beam.

By using this technique, it is possible to obtain quantitative data on, for example, the calcium concentration in different parts of a cell; however, it is necessary to use ultra thin frozen sections.

electron microradiography
The photographic recording and later enlarging of very thin specimens, using an electron beam to form the image.
electron microscope
1. A device which uses electrons, generally focused by electron lenses, to magnify tiny objects onto a fluorescent screen or photographic plate.

It provides much greater plowers of magnification than an optical microscope; that is, up to 1,000,000 times actual size without loss of sharpness and degree of contrast in the image.

2. An electronic instrument that scans cell and tissue sections with a beam of electrons instead of visible light.

The specimen is stained with electron-opaque dyes and with its high magnification power, it creates an image that can be photographed or viewed on a florescent screen.

3. A device for directing streams of electrons by means of electric and magnetic fields in a manner similar to the direction of visible light rays by means of glass lenses in an ordinary microscope.

Since electrons carry waves of much smaller wavelengths than light waves, correspondingly greater magnifications can be obtained.

The electron microscope will resolve details from 1,000 to 10,000 times finer than the optical microscope and images can be studied on a fluorescent screen or recorded photographically.

electron microscopist
Someone who is skilled in the use of the electron microscope which used beams of electrons instead of beams of light.
electron mirror, dynode
1. An electron instrument used to totally reflect an electron beam.
2. An electrode that has the primary function of secondary emission of electrons.

It is used in multiplier phototubes and some types of television camera tubes.

electron mobility (s) (noun), electron mobilities (pl)
1. The average electron-drift velocity in a semiconductor divided by the externally applied electric field.
2. A drift mobility of electrons in a semiconductor which consists of the electron velocity divided by the applied electric field.
electron multiplier
1. A tube in which current is amplified by the production of secondary electrons that result from the collisions of electrons with special targets inside the tube.
2. An electron-tube structure that produces current amplification.

An electron beam containing the desired signal is reflected from the surfaces of each of a series of dynodes (electrodes whose primary function is the secondary emission of electrons), and at each reflection an impinging electron releases two or more secondary electrons, so that the beam builds up in strength.

3. An instrument used for amplifying a very small current using the effects of secondary emission.

Electrons from the original current strike an anode, producing secondary electrons that are directed to the next anode in a multistage process until the desired level of current is obtained.

electron multiplier phototube, electron-multiplier phototube, multiplier phototube, photoelectric electron-multiplier tube, photomultiplier, photomultiplier tube
A phototube with one or more dynodes (electrodes the primary function of which is secondary emission of electrons) between its photocathode (photosensitive surface that emits electrons when exposed to light or other suitable radiation) and the output electrode.

The electron stream from the photocathode is reflected off each dynode in sequence, with a secondary emission adding electrons to the stream at each reflection.

electron neutrino, electronic neutrino, e-neutrino
1. A neutrino (a neutral particle with no electric charge and little mass) which obeys a conservation law together with the electron, so that the total number of electrons and electron-neutrinos minus the total number of their antiparticles remains the same.
2. A type of neutrino that obeys a conservation law together with the electron, with the total number of electrons and electron-neutrinos minus the total number of their antiparticles remaining constant.
electron nuclear double resonance, ENDOR
1. A spectroscopic technique in which a sample is irradiated with a range of nuclear resonance frequencies while electron spin resonance absorption is observed at a single frequency.
2. A type of electron paramagnetic resonance spectroscopy permitting greatly enhanced resolution, in which a material is simultaneously irradiated at one of its frequencies and by a second oscillatory field during which its frequency is swept over the range of nuclear frequencies.
electron number (s) (noun), electron numbers (pl)
The quantity of negative charges in atoms or ions: Jack and all the other chemistry students had to memorize the electron numbers from the chart that the teacher presented to them.

The references or sources of information for compiling the words and definitions in this unit are listed at this Electronic Bibliography page or specific sources are indicated when they are appropriate.

A cross reference of word units that are related, directly and/or indirectly, with "electricity": galvano-; hodo-; ion-; piezo-; -tron; volt; biomechatronics, info; mechatronics, info.