Determination of the Stability of the AIO+ Complex in Alkali Halide Melts*

1984 ◽  
Vol 39 (5) ◽  
pp. 499-502 ◽  
Author(s):  
C. M. Wai ◽  
M. Blander
Keyword(s):  
Free Energy ◽  
Bond Strength ◽  
Mole Fraction ◽  
Thermodynamic Data ◽  
Alkali Halide ◽  
Formation Constant ◽  
Activation Technique ◽  
Eutectic Mixtures ◽  
The Stability

The solubilities of Al182O3 in LiCl-KCl eutectic mixtures containing dissolved AlCl3 were measured using a sensitive proton activation technique. The results are consistent with the presence of an A10+ species at 4.7 x 10-5 mole fraction with AlCl3 at 10-2 mole fraction. When combined with other thermodynamic data, these solubilities are used to deduce a formation constant for the A10+ species from Al3+ and O2- ions of 1.94 x 1022 (in mole fraction units) and a specific bond free energy ("bond strength") of 300 kJ mol-1

The pressure dependence of the dehydration of gypsum to bassanite

1987 ◽  
Vol 51 (361) ◽  
pp. 453-457 ◽  
Author(s):  
J. D. C. McConnell ◽  
D. M. Astill ◽  
P. L. Hall
Keyword(s):  
Elevated Temperature ◽  
Experimental Determination ◽  
Volume Change ◽  
Pressure Dependence ◽  
Thermodynamic Data ◽  
Dehydration Reaction ◽  
Temperature And Pressure ◽  
The Stability ◽  
Very High

AbstractA new experimental determination of the stability relationships for the dehydration of gypsum to the hemihydrate mineral bassanite at elevated temperature and pressure is described. The experimental method used depends on the observation of very small changes in pressure on the onset of reaction due to the potential volume change in the reaction. The technique yields P-T data of very high precision for this dehydration reaction, and the method is likely to be of use for other reactions. The experimental P-T results have been compared with those calculated from existing thermodynamic data for this reaction.

scholarly journals Activity of bismuth in liquid Ag-Bi-Ni alloys determined by equilibrium saturation method

2015 ◽  
Vol 51 (1) ◽  
pp. 105-112 ◽  
Author(s):  
P. Fima ◽  
J. Romanowska
Keyword(s):  
Free Energy ◽  
Activity Coefficient ◽  
Gibbs Free Energy ◽  
Mole Fraction ◽  
Thermodynamic Data ◽  
Excess Gibbs Free Energy ◽  
Activity Data ◽  
Experimental Activity ◽  
Ni Alloys ◽  
Saturation Method

Activity coefficients of Bi in liquid Ag-Bi-Ni alloys were experimentally determined by means of the equilibrium saturation method at 1173 and 1273 K. The measurements were carried out for alloy compositions along three sections of fixed Ag to Ni mole fraction ratio equal to 4/1, 3/2, and 2/3. The excess Gibbs free energy of Bi was calculated basing on the experimental activity coefficient data. The experimental activity data were compared to the values calculated for two sets of assessed thermodynamic data.

scholarly journals MICRO DETERMINATION OF DOPAMINE IN BIOLOGICAL SAMPLES BY COUPLING REACTION

2018 ◽  
Vol 22 (4) ◽  
Author(s):  
AHMED JASSIM MUKLIVE AL-OGAIDI
Keyword(s):  
Mole Fraction ◽  
Biological Samples ◽  
Azo Dye ◽  
Coupling Reaction ◽  
Stability Factor ◽  
Relative Standard ◽  
The Stability ◽  
Fraction Method ◽  
Orange Color

The paper presents the development of an analytical method to determine dopamine by coupling reaction with diazotized solution of 4-Aminoantipyrine in basic media to give a compound with a single azo dye salt having orange color soluble in water.  A calibration curve for a range of concentration (9.14x10<sup>-5</sup> – 2.28x10<sup>-3</sup> μg.mL<sup>-1</sup>) was realized and the value of molar absortivity was 1.5x103 L.mol<sup>-1</sup>.cm<sup>-1</sup>, with a relative standard deviation more than 1.26% and a recovery 98.77%. As we study the nature of the azo dye by mole fraction method, from the practical value we found that the mole fraction of the dye compound is 1:1 (dopamine: 4- amino antipyrine) and the stability factor reach to 1.4x106 L.mol<sup>-1</sup>. The described procedure is very simple, low-time-consuming, provides high throughput of examined samples, and could be used for routine screening and confirmatory analyses as well. The method was successfully validated to the analysis of the dopamine in biological samples.

scholarly journals MICRO DETERMINATION OF DOPAMINE IN BIOLOGICAL SAMPLES BY COUPLING REACTION

2016 ◽  
Vol 22 (4) ◽  
pp. 7-12
Author(s):  
AHMED JASSIM MUKLIVE AL-OGAIDI
Keyword(s):  
Mole Fraction ◽  
Biological Samples ◽  
Azo Dye ◽  
Coupling Reaction ◽  
Stability Factor ◽  
Relative Standard ◽  
The Stability ◽  
Fraction Method ◽  
Orange Color

The paper presents the development of an analytical method to determine dopamine by coupling reaction with diazotized solution of 4-Aminoantipyrine in basic media to give a compound with a single azo dye salt having orange color soluble in water. A calibration curve for a range of concentration (9.14x10-5 – 2.28x10-3 μg.mL-1) was realized and the value of molar absortivity was 1.5x103 L.mol-1.cm-1, with a relative standard deviation more than 1.26% and a recovery 98.77%. As we study the nature of the azo dye by mole fraction method, from the practical value we found that the mole fraction of the dye compound is 1:1 (dopamine: 4- amino antipyrine) and the stability factor reach to 1.4x106 L.mol-1. The described procedure is very simple, low-time-consuming, provides high throughput of examined samples, and could be used for routine screening and confirmatory analyses as well. The method was successfully validated to the analysis of the dopamine in biological samples.

Determination of the Bond Strength Between Nanosized Particles

1994 ◽  
Vol 351 ◽  
Author(s):  
Alfred P. Weber ◽  
Sheldon K. Friedlander
Keyword(s):  
Free Energy ◽  
Bond Strength ◽  
Gibbs Free Energy ◽  
Nanosized Particles ◽  
Bond Energies ◽  
Method Of Calculation ◽  
Order Of Magnitude ◽  
Hamaker Constants ◽  
Kinetics Of

ABSTRACTA method has been developed for determining the bond energies between nanosized particles from the kinetics of the rearrangement of aerosol agglomerates. The method of calculation is based on the change in Gibbs' free energy during restructuring. For Ag and Cu agglomerates, bond energies between the nanosized particles are of the order of magnitude calculated from bulk Hamaker constants.

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