activation energy

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ac·ti·va·tion energy

The least amount of energy needed for a chemical reaction to occur. For example, striking a match on the side of a matchbox provides the activation energy, in the form of heat, necessary for the chemicals in the match to catch fire.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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Noun1.activation energy - the energy that an atomic system must acquire before a process (such as an emission or reaction) can occur; "catalysts are said to reduce the energy of activation during the transition phase of a reaction"
energy, free energy - (physics) a thermodynamic quantity equivalent to the capacity of a physical system to do work; the units of energy are joules or ergs; "energy can take a wide variety of forms"
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aktivacijska energija
References in periodicals archive ?
Studies of the electrical conduction mechanism in several glass systems showed that the thermal activation energy plays a dominant role in electrical conduction (Panchal, 2014; Dhote, 2014).
The phenomenon can be attributed to the fact that higher temperature can enhance the thermal activation of atoms, decrease the atomic critical shear stress, and increase the softening degree of the material.
It is indicated that the carrier transport mechanism of Ge NCs films above room temperature is the thermal activation conduction in the extended states [32].
The thermal activation of samples was performed utilizing Closed Muffle furnace (Phoenix, Sheffield, England 1983) at temperature extending from 100 - 200 degC and heating rate of 10C/min under nitrogen stream of 500 mL/min for 5 h to increase the surface area of biosorbent.
From the Table 3 it is clear that after calcinations the quantity of quartz (raw impurities) was 82.19% decreased in DWPS than the WPS samples, and upon decreasing of quartz as a raw impurity, pozzolanic reactivity he thermal activation of waste paper sludge was carried out in a electric oven at (600, 700 and 800 degC) for1, 2 and 3 hours.
There have been several studies of the kinetics of the gas phase decomposition of halogenated hydrocarbons using thermal activation techniques over temperature range of 550 750 K and these have been reviewed.
Techniques used to assist PS oxidation in the treatment of water and waste water include; thermal activation [8-10], photochemical activation [11-13], ferrous Ion activation [14, 15], chelated ferrous Ion activation [16], zero-valent iron activation [17, 18], mineral activation [19, 20], activated carbon/PS activation [21], [22, 23], microwave activation [24], and integrated activation [25, 26].
Furthermore, a correlation between the applied strain rale and filler loading with rate sensitivity, thermal activation volume, and absorbed energy up to a certain defonnation (0.025 of strain) was also made.
A low-energy thermal activation process (lofting) activates a spunlaid web causing it to "selfbond," increase volume and/or become "elastic like." The interlocking of the fibers in the nonwoven structure means no further bonding process is required after activation, eliminating the need for the more conventional calender or costly needleloom in some applications.
The analysis of diode parameters of the second term in the expression (2) showed that the excess current is characterized by a thermally independent potential [E.sub.t] (0.17 V) and weak (in comparison with the thermal activation dependence) exponential temperature dependence of [J.sub.ot].