Prediction of the Standard State Partial Molar Volume of Aqueous Electrolytes to High Temperatures and High Pressures

2015 ◽  
Vol 60 (12) ◽  
pp. 3792-3799 ◽  
Author(s):  
Essmaiil Djamali ◽  
Walter G. Chapman ◽  
Kenneth R. Cox
Keyword(s):  
Molar Volume ◽  
High Temperatures ◽  
Partial Molar Volume ◽  
High Pressures ◽  
Aqueous Electrolytes ◽  
Standard State

High Pressure Carbon Behavior Induced from Carbide Hugoniots

1997 ◽  
Vol 499 ◽  
Author(s):  
T. Sekine ◽  
E. Takazawa ◽  
T. Kobayashi
Keyword(s):  
High Pressure ◽  
Phase Transitions ◽  
Molar Volume ◽  
Partial Molar Volume ◽  
High Pressures ◽  
Diamond Structure ◽  
Structural Variations ◽  
Diamond Phase ◽  
Type Carbide ◽  
Diamond Type

ABSTRACTInvestigations of Hugoniots the diamond-type carbides(various SiC) and NaCl-type carbides such as TiC give some insights into the high-pressure carbon behaviors. The experimental results of phase transitions of a-SiC and β-SiC, together with those of diamond-structure Si, imply that the candidate as post-diamond phase has sixfold coordination and that a possible transition pressure is about 1–2 TPa. The NaCl-type carbide Hugoniots indicate that sixfold coordinated C is very stable at high pressures. The partial molar volume of carbon in the NaCl-type carbides ranges between 1.4 to 2.6 cnvVg-atom C at 1 atm and reaches about 2.8 cm3/g-atom C at 100 GPa. Taking into account structural variations of the corresponding metals, the volume of the sixfold coordinated C is estimated to be 1.7 cm3/g-atom C, about half of that of diamond, and the post-diamond phase appears to be extremely hard.

scholarly journals A New Density Model of Quartz Solubility in H2O-CO2-NaCl Ternary Systems up to High Temperatures and High Pressures

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-23
Author(s):  
Weiping Deng ◽  
Qing Wei ◽  
Xuan Liu
Keyword(s):  
Experimental Data ◽  
Molar Volume ◽  
Partial Molar Volume ◽  
High Pressures ◽  
Pure Water ◽  
Molar Fraction ◽  
Density Model ◽  
Liquid Region ◽  
Lower Accuracy ◽  
Quartz Solubility

A novel density model for computing quartz solubility in H2O-CO2-NaCl hydrothermal fluids applicable to wide ranges of temperature and pressure is proposed. Based on the models of Akinfiev and Diamond (2009) and Wei et al. (2012), the effective partial molar volume of water ( V H 2 O ∗ ) is replaced by the partial molar volume of water ( V ¯ H 2 O ) by implementing an empirical correction, and water molar fraction ( x H 2 O ) is modified with water activity ( a H 2 O ), in addition to a series of changes to the model coefficient forms. The absolute values of averaged relative deviation of this model compared to the experimental data sets in pure water, H2O-CO2, and H2O-NaCl solutions are 5.74%, 6.69%, and 7.09%, respectively, which are better than existing models in the literature. The model can be reliably used for computing quartz solubilities in pure water from 0°C to 1000°C, from 0 bar to 20,000 bar, and in CO2- and/or NaCl-bearing solutions from 0°C to 1000°C, from 0 bar to 10,000 bar (with slightly lower accuracy at 5000-10,000 bar in H2O-NaCl systems) in the single liquid region. Moreover, the trends and overall ranges of this model may probably be more accurate in the H2O-CO2-NaCl fluid mixtures compared to the limited experimental data. In addition, a bisection algorithm for deriving the isopleths of quartz solubilities based on this new model is first proposed, and application perspectives are discussed for various geologic settings including subduction zone, lower crust-upper mantle, migmatite, pegmatite, porphyry, and orogenic deposits.

The molar volume and fugacity of liquid dibenzofuran at high temperatures and high pressures

1984 ◽  
Vol 16 (3) ◽  
pp. 199-205 ◽  
Author(s):  
Pervaiz Nasir ◽  
Alwarappa Sivaraman ◽  
Riki Kobayashi
Keyword(s):  
Molar Volume ◽  
High Temperatures ◽  
High Pressures

Brillouin scattering study of liquid methane under high pressures and high temperatures

2010 ◽  
Vol 133 (4) ◽  
pp. 044503 ◽  
Author(s):  
Min Li ◽  
Fangfei Li ◽  
Wei Gao ◽  
Chunli Ma ◽  
Liyin Huang ◽  
...  
Keyword(s):  
High Temperatures ◽  
High Pressures ◽  
Brillouin Scattering ◽  
Scattering Study ◽  
Liquid Methane

scholarly journals Gaseous combustion at high pressures. —Part X. The co-volume corrections, maximum temperatures and dissociation of steam and carbon dioxide in explosions

1928 ◽  
Vol 119 (782) ◽  
pp. 464-480
Keyword(s):  
Carbon Dioxide ◽  
High Pressure ◽  
Internal Energy ◽  
High Temperatures ◽  
High Pressures ◽  
Internal Combustion ◽  
Systematic Survey ◽  
Explosion Method ◽  
Maximum Temperatures ◽  
Very High

During the researches upon high-pressure explosions of carbonic oxide-air, hydrogen-air, etc., mixtures, which have been described in the previous papers of this series, a mass of data has been accumulated relating to the influence of density and temperature upon the internal energy of gases and the dissociation of steam and carbon dioxide. Some time ago, at Prof. Bone’s request, the author undertook a systematic survey of the data in question, and the present paper summarises some of the principal results thereof, which it is hoped will throw light upon problems interesting alike to chemists, physicists and internal-combustion engineers. The explosion method affords the only means known at present of determining the internal energies of gases at very high temperatures, and it has been used for this purpose for upwards of 50 years. Although by no means without difficulties, arising from uncertainties of some of the assumptions upon which it is based, yet, for want of a better, its results have been generally accepted as being at least provisionally valuable. Amongst the more recent investigations which have attracted attention in this connection should be mentioned those of Pier, Bjerrum, Siegel and Fenning, all of whom worked at low or medium pressures.

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