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ambient [ 16 , 17 ] and at low temperature [ 18 ] and at high pressures [ 19 ]; however, no solid–solid phase transition has been detected. Earlier heat capacities of samples of l -cysteine and l -cystine were measured in the temperature range

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Abstract  

The heats of solution of tetrabutylammonium bromide have been measured in mixtures of formamide (FA) with methanol (MeOH) and ethylene glycol (EG) at 313.15 K by calorimetric method. The standard enthalpies of solution in binary mixtures have been extrapolated to infinite dilution by Redlich–Rosenfeld–Meyer type equation using the literary data at 298.15 K and the present paper data at 313.15 K. The Debye–Hückel limiting law slope A H required for calculation of the ∆sol H 0 value has been obtained with application the new additive scheme of determination of the physic-chemical characteristics of binaries. The scheme is tested on the example of Bu4NBr solutions in FA–MeOH mixture at 298.15 K. Its application yields the ∆sol H 0 value very closed on the ones determined with the real (non-additive) characteristics of binaries. The standard enthalpies of solution extrapolated by Redlich–Rosenfeld–Meyer type equation are in a good agreement with the ones computed in terms of the Debye–Hückel theory in the second approximation. The heat capacities characteristics of Bu4NBr have been calculated in H2O–FA, MeOH–FA and EG–FA mixtures using the literary and present data. The sequence of solvents H2O > FA > EG > MeOH located on their ability to solvophobic solvation found by us earlier for enthalpic characteristics is confirmed by the ∆C p 0 values. The comparison of thermochemical characteristics of Bu4NBr solutions in aqueous and non-aqueous mixtures containing FA has been carried out. The own structure of water remains in the region of small additions of formamide to co-solvents. It considerably differs the H2O–FA mixture from the investigated non-aqueous systems.

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by transient heat transfer equation with convective term 1 where λ = λ ( T ) is thermal conductivity dependent on temperature, C ef is effective heat capacity, is a volumetric heat source and v = v (x,y,z, t ) is a vector determined by

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diversified than those in which simpler molecules take part. The results of heat capacity measurements of alkanediol in methanol made it possible to determine the molar heat capacity of the interaction between alkanediol molecule and methanol, Δ C p(int) [ 15

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Pollack Periodica
Authors:
Istvan Ervin Haber
,
Gergely Bencsik
,
Basma Naili
, and
Istvan Szabo

has been modified by a device, which sends fake temperature data from the tested room. The thermodynamic properties and the control method are described in the followings. 2.1 Heat capacity and heat resistance A building, which has been built by

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fluid ( bf ) and Tungsten oxide WO 3 nanoparticle subscribed by ( np ) to define the density ( ρ ), specific heat capacity ( C p ), thermal conductivity ( k ) and dynamic viscosity ( μ ) that lead enhancement in the thermal efficiency. The effect of

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. 2 below its base line. This is reasonable considering the large heat capacity of H 2 O. The measurements in Fig. 3 (maximum TMA pulse) were recorded after the campaign in Fig. 2 (maximum H 2 O pulse). By comparing the magnitude of the

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. Fig. 2. Labtech BL20001 electronic compact scale The mass of each specimen was taken and recorded in grams, the specific heat capacity adopted for each

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for NaI–non-electrolyte pairs in water, and the heat capacity of interactions, C p (int) between the non-electrolyte Y and solvent water [ 7 ] (Fig. 2 ). Similar correlations were obtained when the NaI was replaced by NaCl, or by polar non

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, pp. 137 – 158 . Scharli , U. , L. Rybach 2001 : Determination of the specific heat capacity on rock fragments . — Geothermics , 30 , pp. 93 – 110

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