enthalpy

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en·thal·py (H),

(en'thal-pē),
Heat content, symbolized as H; a thermodynamic function, defined as E + PV, where E is the internal energy of a system, P the pressure, and V the volume; the heat of a reaction, measured at constant pressure, is ΔH.
Synonym(s): heat (4)
[G. enthalpō, to warm in]

enthalpy

/en·thal·py/ (en´thal-pe) the heat content or chemical energy of a physical system; a thermodynamic function equal to the internal energy plus the product of the pressure and volume. Symbol H.

en·thal·py

(H) (en'thal-pē)
Heat content, symbolized as H; a thermodynamic function, defined as E + PV, where E is the internal energy of a system, P the pressure, and V the volume; the heat of a reaction, measured at constant pressure, is ΔH.
Synonym(s): heat (3) .
[G. enthalpō, to warm in]

enthalpy

the bond energy in a biochemical reaction.
References in periodicals archive ?
Dimensional analysis of Equation (14), introduces the following dimensionless parameters in Equation (22); [epsilon]([PHI]) represents a ratio of effective intrapellet diffusivities at intrapellet temperature Tpellet relative to temperature on the external surface of the catalyst, [xi]([PHI]) is the ratio of the enthalpy change for chemical reaction at intrapellet temperature [T.
Specific enthalpy changes at the melting temperature were determined for the annealed fibers by DSC.
Figure 4 shows a comparison of saturated vapor enthalpy change of ammonia-water mixtures with respect to the enthalpy at zero ammonia mass concentration and plotted against ammonia vapor mass concentration at a pressure of 50 bar (725 psia).
Melting, crystallization temperatures and enthalpy changes for neat PP, PET, and their blends are listed in Table 2: DSC measurement results.
In the uncoupled formulation for crystallization, the enthalpy change from microscopic calculations (micro-enthalpy) does not contribute to the macroscopic enthalpy change when updating the temperature for each time step.
Rolled amorphous samples may contain small paracrystals that are expected to reorganize into perfect crystals with a smaller enthalpy change.
Differential thermal analysis device is one of the thermal identification and analysis devices, which is used for the determination of enthalpy changes and the value of specific heat capacity of materials at constant pressure in an exothermic or endothermic chemical reaction.
Energy was calculated by enthalpy changes by equations (2-4) of mean heat capacities shown below.
Depending between parameters in characteristic points of cooling system can be described with energy equation, with equation of consume balance of energy bearers, equation of hydraulic balance and as well with equation of enthalpy changes of energy bearers (Sacadura 1993).
Introducing this text as one that fills a vacuum in data books and databases detailing enthalpy changes (i.
3], OMe, OH, tert-butyl and other functional groups, and considered enthalpy changes on reaction with various free radicals.