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]

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]
References in periodicals archive ?
Caption: Figure 6: Entropy and enthalpy change with moles of lithium intercalated in anodes.
From curves like the ones shown in Figure 2 calculate the immersion enthalpy of solids in solutions that are tested in conditions of low and high dilution with the purpose of comparing the enthalpy change of the immersion process.
The free energy change ([DELTA]G), enthalpy change ([DELTA]H), entropy change ([DELTA]S) and energy of activation ([E.sub.a]) for the lipase catalyzed reaction were found to be -23.2 kJ [mol.sup.-1], 15.9 kJ [mol.sup.-1], 124.7 J [K.sup.-1] [mol.sup.-1] and 19.1 kJ [mol.sup.-1], respectively.
Therefore, it can be concluded that both physical and chemical adsorption played a prominent role in the adsorption process additionally when the enthalpy change for the process was high.
Inspite of remarkable lowering of ofloxacin melting temperature thermal events unambiguously characteristic of the drug did hardly experience an enthalpy change. As a matter of fact, neither the drug nor the combined system of drug with any of these diluents suffered any enthalpy loss.
Utilizing isothermal titration calorimetry, the enthalpy of binding was measured and our results show a large enthalpy change (AH) in the binding of actinomycin D to the two sequences that only differ by the presence of one guanine.
The summation of products of stoichiometric coefficients and partial molar enthalpies, over all species in the reactive mixture, is an exact representation of the enthalpy change for chemical reaction, ?HReaction, on a molar basis (Tester and Modell, 1997).
The molar enthalpy (heat) of vaporisation IHvap, which is characterized by the enthalpy change in the transformation of one mole of fluid to gas at a consistent temperature.
The enthalpy changes, [DELTA][H.sub.m], related to [T.sub.m] and the summed enthalpy change, [DELTA][H.sub.c], of the crystallization at [T.sub.c1] and [T.sub.c2], and the degree of crystallinity are also listed in Table 2.
Thermodynamic study was also carried out to evaluate different parameters like free energy change (G) enthalpy change (H) and entropy change (S) and biosorption process was found to be exothermic.
The enthalpy change ([DELTA]H) of the reaction was estimated at -26.23 kJ x [mol.sup.-1], which indicates an exothermic reaction.