Results 251 to 260 of about 957,237 (288)

Total phase change entropies and enthalpies. An update on fusion enthalpies and their estimation

Thermochimica Acta, 2009
Abstract This compendium summarizes the fusion enthalpies of approximately 1000 new measurements. A group additivity method developed to estimate the total phase change entropies and enthalpies of organic solids is updated, applied to the new data and the results are compared.
James S. Chickos, William E. Acree
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Fusion enthalpy and entropy of syndiotactic polystyrene

Polymer, 1990
Abstract The fusion enthalpy and entropy of a highly syndiotactic polystyrene sample were determined by melting point depression in the presence of diluents. Three solvents were used to ascertain the presence, if any, of polymorphic modifications: dioctyl phthalate, diphenylsulphone and diphenyldiketone (benzil).
G. Gianotti, A. Valvassori
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Direct measurement of the enthalpy of fusion of diopside

Geochimica et Cosmochimica Acta, 1986
Crystalline diopside, CaMgSi2O6, was dropped directly into a Setaram “HT1500” calorimeter operating at high temperature. At 1575 < T < 1624 K, the heat content of the crystals was in excellent agreement with previously published results. Above 1634 K, a rise in the enthalpy was seen, supporting the incongruent melting reported by Kushiro.
David Ziegler, Alexandra Navrotsky
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Fusion enthalpy and entropy of isotactic polypropylene

European Polymer Journal, 1968
Abstract The “equilibrium melting temperature” of isotactic polypropylene and of a number of its mixtures with hexadecane, α-chloronaphthalene, decalin and naphthalene is determined by extrapolation of several experimental melting temperature data obtained by rapid melting of each sample isothermally crystallized at different temperatures.
F. Danusso, G. Gianotti
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Estimating entropies and enthalpies of fusion of hydrocarbons

The Journal of Organic Chemistry, 1990
A group additivity method for estimating fusion entropies and fusion enthalpies is described. The method is based on experimental fusion enthalpies of 191 hydrocarbons. Group values are provided for most structural environments. Applications of the technique are described, and comparisons with literature values and other estimation techniques are also ...
James S. Chickos, Donald G. Hesse, Joel F. Liebman   +2 more
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Thermochemistry of phase transitions of aromatic amines: Estimation of the sublimation enthalpy at 298.15 K through the fusion enthalpy [PDF]

Journal of Chemical Thermodynamics, 2017
© 2017 Elsevier Ltd In the present work two methods of determination of sublimation enthalpies at 298.15 K based on solution enthalpies at 298.15 K and fusion enthalpies at the melting temperatures were applied for aromatic amines.
Ruslan Nagrimanov, Mikhail Yagofarov
exaly   +1 more source

Determination of the enthalpy of fusion of NaMgF3 and KMgF3

Thermochimica Acta, 1994
Abstract The enthalpy of melting of NaMgF3 and KMgF3 at the dystectic temperature of fusion of these compounds was determined using a high-temperature calorimeter, the Setaram HTC 1800 K. It was found that ΔfusHm(NaMgF3; 1303 K) = (66 ± 4) kJ mol−1 and ΔfusHm(KMgF3; 1343 K) = (96 ± 5) kJ mol−1.
K. Adamkovičová, P. Fellner, L. Kosa, I. Nerad, I. Proks, J. Strečko   +5 more
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ENTHALPY AND ENTROPY OF FUSION OF ISOTACTIC POLYSTYRENE

1967
ABSTRACT The enthalpy of fusion Δ H u of isotactic polystyrene, determined from measurements of the depression of the melting point of the polymer in the presence of diluents by the dilatometric method at equilibrium, was 2150 cal/structural unit (±100).
F. DANUSSO, G. MORAGLIO
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Estimate of Enthalpies of Formation and Fusion of Cordierite

Journal of the American Ceramic Society, 1973
The enthalpies of solution in molten 2PbO·B 2 O 3 at 690°±2°C of cordierite, Mg 2 Al 4 Si 5 O 18
A. NAVROTSKY, O. J. KLEPPA
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Heat Capacity and Enthalpy of Fusion of Fenoxycarb

Chinese Journal of Chemistry, 2005
AbstractFenoxycarb was synthesized and its heat capacities were precisely measured with an automated adiabatic calorimeter over the temperature range from 79 to 360 K. The sample was observed to melt at (326.31±0.14) K. The molar enthalpy and entropy of fusion as well as the chemical purity of the compound were determined to be (26.98±0.04) kJ·mol‐1 ...
Sun Xiao‐Hong, Liu Yuan‐Fa, Tan Zhi‐Cheng, Jia Ying‐Qi, Yang Jian‐Wu, Wang Mei‐Han   +5 more
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