| drift velocity | <radiobiology> Characteristic velocity at which the centre of a particle's orbit (guiding centre) drifts when drift motion (see above) occurs. (09 Oct 1997) |
|---|---|
| initial velocity | The rate of a reaction, e.g., an enzyme-catalyzed reaction, at the early stages of the reaction such that the product(s) concentrations have not risen to a level to significantly affect the observable rate; typically, initial velocities are observed when less than 10% of the reaction's approach toward equilibrium has occurred. Synonym: initial rate. (05 Mar 2000) |
| thermal | Pertaining to or characterised by heat. (18 Nov 1997) |
| thermal anaesthesia | Loss of temperature appreciation. (05 Mar 2000) |
| thermal barrier | <radiobiology> In magnetic mirror devices, this is a depression of electrostatic potential formed by enhancing ion loss in the region between the central cell and the positive potential plug. The thermal barrier significantly reduces the density requirements in the plug and lowers the overall power required to sustain the solenoidal plugging by thermally decoupling central cell electrons from the end plugs. (09 Oct 1997) |
| thermal burn | A burn caused by heat. (05 Mar 2000) |
| thermal capacity | <chemistry> The amount of energy required to raise the temperature of an object by one degree Celsius (or Kelvin), it is represented by the symbol C and is given in units of J/K. (09 Jan 1998) |
| thermal conductivity | <radiobiology> Degree to which a substance transmits heat. (basic definition, I believe, is: (heat flow) = (thermal conductivity) (temperature gradient)) (09 Oct 1997) |
| thermal conversion cycle | <radiobiology> Process of generating electrical power with a fusion reactor by means of a steam / other gas turbine. This is distinct from direct conversion cycles. (09 Oct 1997) |
| thermal cover | Vegetative condition, generally with greater than 70% canopy closure and 40 feet in height, that can significantly ameliorate weather effects such as wind, heat, cold, and snow. Used by wildlife in winter. (05 Dec 1998) |
| thermal efficiency | <radiobiology> Ratio of the electric power produced by a power plant to the original amount of heat produced. This measures the efficiency with which the thermal energy is converted to electricity. (09 Oct 1997) |
| thermal expansion | <radiobiology> Characteristic property of most solids and liquids which causes their volume to increase when they are heated. Thermal expansion and contraction can cause structural problems in pulsed fusion devices. (09 Oct 1997) |
| thermal melting profile | In general a record of the phase state of a system over a temperature range. Phase changes can be detected by exothermy or endothermy. Valuable in studying lipid and DNA structures. (18 Nov 1997) |
| thermal neutron | <radiobiology> A neutron in thermal equilibrium with its surrounding environment. Thermal neutrons are those that have been slowed down by a moderator to speeds characteristic of the local temperature. Compare: fast neutron. (09 Oct 1997) |
| thermal resource | A facility that produces electricity by using a heat engine to power an electric generator. The heat may be supplied by the combustion of coal, oil, natural gas, biomass, or other fuels, including nuclear fission, solar, or geothermal resources. (05 Dec 1998) |