Results found: 3

Number of results on page

Search results

Search:
in the keywords: heat capacity

Sort By:

Limit search:

Analysis of heat capacity and Mössbauer data for LuZnSn2compound

100%

Łątka K., Przewoźnik J., Żukrowski J., Verbovytskyy Y., Gonçalves A. P.

Nukleonika

2015

vol. 60

issue 1

97-101

New analysis of heat capacity data is presented for LuZnSn2 compound that takes into account anharmonic effects together with the existence of Einstein modes. 119mSn Mössbauer spectroscopy was used to monitor the hyperfine parameters at the two crystallographically inequivalent Sn sites in the studied compound. The problem of non-unique mathematical resonance spectrum description and the problem how to choose physically meaningful set of hyperfine parameters will be thoroughly discussed. Measured quadrupole interaction constants by 119mSn Mössbauer spectroscopy give estimations for Vzz component of electric field gradient tensor at both Sn sites in LuZnSn2.

Model study on steady heat capacity in driven stochastic systems

100%

Pešek J., Boksenbojm E., Netočný K.

Open Physics

2012

vol. 10

issue 3

692-701

We explore two- and three-state Markov models driven out of thermal equilibrium by non-potential forces, to demonstrate basic properties of the steady heat capacity based on the concept of quasistatic excess heat. It is shown that large enough driving forces can make the steady heat capacity negative. For both the low- and high-temperature regimes we propose an approximative thermodynamic scheme in terms of “dynamically renormalized” effective energy levels.

Thermochemical properties of the Fe-analogue of cryolite, Na3FeF6

100%

Nerád I., Mikšíková E.

Open Chemistry

2007

vol. 5

issue 2

508-515

Relative enthalpies for low-and high-temperature modifications of Na3FeF6 and for the Na3FeF6 melt have been measured by drop calorimetry in the temperature range 723–1318 K. Enthalpy of modification transition at 920 K, δtransH(Na3FeF6, 920 K) = (19 ± 3) kJ mol−1 and enthalpy of fusion at the temperature of fusion 1255 K, δfusH(Na3FeF6, 1255 K) = (89 ± 3) kJ mol−1 have been determined from the experimental data. Following heat capacities were obtained for the crystalline phases and for the melt, respectively: C p(Na3FeF6, cr, α) = (294 ± 14) J (mol K)−1, for 723 = T/K ≤ 920, C p(Na3FeF6, cr, β) = (300 ± 11) J (mol K)−1 for 920 ≤ T/K = 1233 and C p(Na3FeF6, melt) = (275 ± 22) J (mol K)−1 for 1258 ≤ T/K ≤ 1318. The obtained enthalpies indicate that melting of Na3FeF6 proceeds through a continuous series of temperature dependent equilibrium states, likely associated with the production of a solid solution. [...]

Refine search results

1 Nukleonika

1 Open Chemistry

1 Open Physics

1 2015

1 2012

1 2007

1 Boksenbojm E.

1 Gonçalves A. P.

1 Mikšíková E.

1 Nerád I.

1 Netočný K.

1 Pešek J.

1 Przewoźnik J.

1 Verbovytskyy Y.

1 Łątka K.

1 Żukrowski J.

Search results

Analysis of heat capacity and Mössbauer data for LuZnSn2compound

Model study on steady heat capacity in driven stochastic systems

Thermochemical properties of the Fe-analogue of cryolite, Na3FeF6