| activation energy | <chemistry> The amount of energy (expressed in joules) that is needed to convert all the molecules in one mole of a reacting substance from a ground state to the transition state. (06 May 1997) |
|---|---|
| binding energy | <chemistry, radiobiology> The binding energy of a nucleus is the minimum energy required to dissociate it into its component neutrons and protons. Neutron or proton binding energies are those required to remove a neutron or proton, respectively, from a nucleus. Electron binding energy is that required to remove an electron from an atom or a molecule. (16 Dec 1997) |
| bioelectric energy sources | Implantable devices which convert biological energy (chemical energy of the metabolism of continuously regenerating body fluids or mechanical energy of periodic movements) to electrical energy. The sources include biogalvanic cells, biofuel cells, and ionic concentration cells. (12 Dec 1998) |
| biomass energy | See Bioenergy. (05 Dec 1998) |
| bond dissociation energy | This is the energy needed to break the bonds between two linked atoms. (09 Oct 1997) |
| bond energy | The energy needed to break a molecular bond. (09 Oct 1997) |
| radiant energy | Energy contained in light rays or any other form of radiation. (05 Mar 2000) |
| radiography, dual-energy scanned projection | A method of producing a high-quality scan by digitizing and subtracting the images produced by high- and low-energy X-rays. (12 Dec 1998) |
| radiotherapy, high-energy | Radiotherapy using high-energy (megavolt or higher) ionizing radiation. Types of radiation include gamma rays, produced by a radioisotope within a teletherapy unit; X-rays, electrons, protons, alpha particles (helium ions) and heavy charged ions, produced by particle acceleration; and neutrons and pi-mesons (pions), produced as secondary particles following bombardment of a target with a primary particle. (12 Dec 1998) |
| geothermal energy | Energy derived from the natural heat of the Earth contained in hot rocks, hot water, hot brines or steam. (05 Dec 1998) |
| mass energy absorption coefficient | <physics> The mass energy absorption coefficient, uen/p of a material for uncharged ionising particles is the product of the mass energy transfer coefficient, utr/p and (1 - g) where g is the fraction of the energy of secondary charged particles that is lost to bremsstrahlung in the material. (16 Dec 1997) |
| Gibbs energy of activation | The Gibbs energy that must be added to that already possessed by a molecule or molecules in order to initiate a reaction. (05 Mar 2000) |
| gibbs free energy | The total amount of energy which is either used up or released during a chemical reaction. Gibbs free energy (delta G) = (delta H) - t (delta s): where (delta H) is the change in enthalpy, calculated by adding up the amount of energy released or used up to break or form chemical bonds during the reaction, t is the temperature at which the reaction took place, and (delta S) is the change in entropy, or amount of disorder, that occurs in the molecules involved during the reaction. (09 Oct 1997) |
| renewable energy resource | <ecology> An energy resource replenished continuously or that is replaced after use through natural means. Sustainable energy. Renewable energy resources include bioenergy, solar energy, wind energy, geothermal power, and hydropower. (25 Jun 1999) |
| resonance energy transfer | <technique> Transfer of energy from one fluorochrome to another. The emission wavelength of the fluorochrome excited by the incident light must approximately match the excitation wavelength of the second fluorochrome. If light at the second emission wavelength is detected, it implies that the two fluorochromes were physically within a few nanometres. Used as a technique to probe protein or cell interactions. (25 Jun 1999) |