Heat conduction is the transfer of thermal energy between neighboring molecules in a substance due to a temperature gradient.
Conduction - The transfer of heat by means of direct collisions between adjacent atoms, molecules, or ions ...
CONDUCTION BAND - The unfilled top energy band in a solid. Since this band is not filled, electrons with energies in this band can move easily through the solid, creating an electric current.
Conduction
1. A process of heat transfer through a substance without movement of the substance itself. The rate of transfer depends on the sample length and cross-sectional area, the temperature difference, and the nature of the material.
Conduction: Conduction is a process of heat transport through the physical collisions of the particles making up a substance. Similar to electrical conductivity, substances have heat conductivity.
Saltatory conduction
Saltatory conduction is a means by which action potentials are transmitted along myelinated axons....
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Inside a star, conduction doesn't work because the molecules are too far from one another, so heat moves either by radiation or by convection. Radiation operates where the gas of the star is transparent, as it is when it is especially hot.
ionic conduction Any electrical conduction where the current is sustained by the motion of ions (as opposed to electrons) within the conductor. All electrical conduction in the atmosphere is of this type. ionic mobility = ion mobility.
In a semiconductor, a mobile conduction electron or hole.
2. In modulation of a signal, a wave suitable for being modulated as a sine wave, a recurring series of pulses, or a direct current.
Another heat transport mechanism is conduction. In conduction heat is carried not by photons but by other particles, most often by fast moving electrons.
Energy Transport: Recall from the discussion about how energy flows in planetary atmospheres that energy moves from hot to cold via conduction, radiation, or convection.
In other departments of physics may be mentioned his paper on the conduction of heat in crystals (1851) and his inquiries in connection with Crookes radiometer; ...
The subsequent movement of electrons into the conduction band creates positive holes in the valence band. Slight impurities in the silver halides act as traps, immobilising the electrons to prevent them recombining with holes.
This is in fair agreement with the computed temperature due to the sun's radiation upon a perpendicular absorbing surface when no temperature is lost through conduction to the interior.
Conduction is negligible since the Nusselt number is much greater than unity. Evaporation (perspiration) is only required if radiation and convection are insufficient to maintain a steady state temperature.
The coronal loops, at up to nine million degrees Fahrenheit, probably heat the moss by thermal conduction, similar to the way heat moves along an iron bar if one end is placed in a fire.
In poor solid conductors (insulators) there are no conduction electrons and the transfer is only by vibrations of atoms or molecules in the crystal structure.
2. Passage of charge through a sample under the influence of an electric field.
The role of the impurity is to produce luminescent centers energetically between the valence and conduction bands of the host crystal. Below 100 keV, X-ray interactions for both NaI and CsI are predominately through the .
Heat can be transferred from one place to another by three methods: conduction in solids, convection of fluids (liquids or gases), and radiation through anything that will allow radiation to pass.
Suppose a "parcel of air" (that's the term you see) is heated near the ground by conduction of heat, the flow of heat due to direct contact with the warm surface.
The high day-side temperatures and cold night-side temperatures on the Moon and Mercury result from the absence of significant heat conduction or atmospheric blanketing on the planet.
Thomson pointed out that the Earth is losing heat by conduction and that the nature of geologic processes may have changed as a consequence; he also concluded that this cooling placed an upper limit on the age of the Earth.
The first American spacewalk, testing the performance of the astronauts and capsule, evaluating work procedures, schedules, and flight planning for an extended length of time in space, demonstrating ExtraVehicular Activity (EVA) in space, conduction ...
This heat transfer may occur via conduction, convection or radiation (see heat for additional discussion of the various mechanisms of heat transfer). The formal properties of temperature are studied in thermodynamics.
formation of the spiral troughs has been attributed to the spin of the planet - that is, ice closer to poles moves slower than ice farther away, causing cracking. In another model, increased solar heating in certain areas and lateral heat conduction ...
A surprise has been the high temperature of the departing gas, at least in part heated by conduction from the surrounding intracluster gas. Can star formation continue for lonh in this environment? Maybe...
 See also: Energy, Temperature, Time, Light, Earth
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