| HFHV | high frequency, high volume |
|---|---|
| HFO | high-frequency oscillator; high-frequency oscillatory [ventilation] |
| HFT | high-frequency transduction; high-frequency transfer |
| HIHA | high impulsiveness, high anxiety |
| HPF | heparin-precipitable fraction; hepatic plasma flow; high-pass filter; high-power field [microscope];... |
| energy crop | Crops grown specifically for their fuel value. These include food crops such as corn and sugarcane, and nonfood crops such as poplar trees and switchgrass. Currently, two energy crops are under development: short-rotation woody crops, which are fast-growing hardwood trees harvested in 5 to 8 years, and herbaceous energy crops, such as perennial grasses, which are harvested annually after taking 2 to 3 years to reach full productivity. (05 Dec 1998) |
|---|---|
| Energy Dispersive Spectroscopy | <technique> A microanalytical technique that is based on the characteristic X-ray peaks that are generated when the high energy beam of the electron microscope interacts with the specimen. Each element yields a characteristic spectral fingerprint that may be used to identify the presence of that element within the sample. The relative intensities of the spectral peaks may be used to determine the relative concentrations of each element in the specimen. The X-ray signal is detected by a solid-state silicon-lithium detector and the construction and efficiency of this detector sets a lower limit on the atomic number that may be detected. Generally elements heavier than carbon (Z=5) are detectable. Acronym: EDS (05 Aug 1998) |
| energy-generating resources | Natural energy sources of power supply. (12 Dec 1998) |
| energy intake | Total number of calories taken in daily whether ingested or by parenteral routes. (12 Dec 1998) |
| energy metabolism | Those metabolic reactions whose role is to release or to provide energy. (05 Mar 2000) |
| energy of activation | Energy that must be added to that already possessed by a molecule or molecules in order to initiate a reaction; usually expressed in the Arrhenius equation relating a rate constant to absolute temperature. (05 Mar 2000) |
| energy of position | <chemistry> Energy due to position, it is stored energy which can be used to do work. (09 Jan 1998) |
| energy principle | <radiobiology> In magnetohydrodynamic theory, this principle states that a perturbation is unstable if it reduces the stored potential energy of the system (and thus allows the conversion of potential energy to kinetic energy of the instability). For more details consult reference 6. (09 Oct 1997) |
| energy replacement time | <radiobiology> Time required for a plasma to lose (via radiation or other loss mechanisms) an amount of energy equal to its average kinetic energy. (09 Oct 1997) |
| energy-rich bond | See: high energy compounds. (05 Mar 2000) |
| energy-rich phosphates | Those phosphate's that, on hydrolysis, yield an unusually large amount of energy; e.g., nucleotide polyphosphates such as ATP, enol phosphate's such as phosphoenolpyruvate. See: high energy compounds. Synonym: energy-rich phosphates. (05 Mar 2000) |
| energy transfer | The transfer of energy of a given form among different scales of motion. In biochemistry, this concept generally refers to the transfer of groups from compounds that contain energy-rich bonding arrangements to compounds that have relatively energy-poor bonding characteristics via thermodynamically permissible enzymatic reactions. This principle is a major premise of the interaction between energy-producing and energy-utilizing metabolic pathways in living cells. (12 Dec 1998) |
| zero energy thermonuclear assembly | <radiobiology> A British fusion device in which scientists observed fusion neutrons in 1958. They were erroneously considered to be thermonuclear (coming from particles with a Maxwellian velocity distribution) and were a cause for the initial optimism that fusion energy would be easy. They were actually due to electromagnetic acceleration during a plasma instability, an effect which cannot be scaled up to produce useful energy. (09 Oct 1997) |
| kinetic energy | <chemistry> Energy due to the motion of an object (09 Jan 1998) |
| unit of energy | CGS system: erg, joule, MKS system: newton-meter (joule), FPS system: foot-poundal,gravitational unit: gram-centimeter, gram-meter, kilogram-meter, foot-pound,SI: joule. (05 Mar 2000) |