scholarly journals Thermodynamic Analysis and Calculations of (Fe-Co) Alloy by Modeling and Simulation using Thermo-Calc Software

2018 ◽  
pp. 35-38
Author(s):  
Syed Mahmood Shah ◽  
Nasib Ullah ◽  
Bakhtar Ullah ◽  
Muhammad Shehzad Khan ◽  
Tariq Usman
Keyword(s):  
Phase Diagram ◽  
Free Energy ◽  
Gibbs Free Energy ◽  
Calphad Method ◽  
Negative Deviation ◽  
Activity Curve ◽  
Thermo Calc Software ◽  
Different Temperatures ◽  
The Stability ◽  
Co Alloys

In this paper Thermodynamic calculation is shown. We have found simulation for phase diagram, Gibbs free energy and Activity curve at different temperatures (1200 K, 1225 K and 1250 K). Phase diagrams, Gibbs free-energy and the component activities of (Fe-Co) alloys system were calculated by Calphad method. Results show that the values of Gibbs energy were negative, which shows the stability of (Fe-Co). Negative deviation had occurred from Raoult’s Law in activities, which indicates that there is strong interaction between Fe and Co in (Fe-Co) alloy. By increasing the temperature the activity increases and deviation in activity decreases. For all the thermodynamic calculations the Thermo-Calc software, databases and Calphad method have used.

scholarly journals Thermodynamic Analysis and Calculations of (Fe-Co) Alloy by Modeling and Simulation using Thermo-Calc Software

2018 ◽  
pp. 120-123
Author(s):  
Syed Mahmood Shah ◽  
Nasib Ullah ◽  
Bakhtar Ullah ◽  
Muhammad Shehzad Khan ◽  
Tariq Usman
Keyword(s):  
Phase Diagram ◽  
Free Energy ◽  
Gibbs Free Energy ◽  
Calphad Method ◽  
Negative Deviation ◽  
Activity Curve ◽  
Thermo Calc Software ◽  
Different Temperatures ◽  
The Stability ◽  
Co Alloys

In this paper Thermodynamic calculation is shown. We have found simulation for phase diagram, Gibbs free energy and Activity curve at different temperatures (1200 K, 1225 K and 1250 K). Phase diagrams, Gibbs free-energy and the component activities of (Fe-Co) alloys system were calculated by Calphad method. Results show that the values of Gibbs energy were negative, which shows the stability of (Fe-Co). Negative deviation had occurred from Raoult’s Law in activities, which indicates that there is strong interaction between Fe and Co in (Fe-Co) alloy. By increasing the temperature the activity increases and deviation in activity decreases. For all the thermodynamic calculations the Thermo-Calc software, databases and Calphad method have used.

scholarly journals Modeling, Simulations, Predictions, Calculations and Thermodynamic Assessments of Cobalt-Ferric Binary Alloys System Using Calphad Method and Pbine Database

2020 ◽  
pp. 3-6
Author(s):  
Waseem Ullah Shah ◽  
Dil Faraz khan1 ◽  
Shahzeb Burki ◽  
Mohib Ullah Khan ◽  
Haiqing Yin
Keyword(s):  
Phase Diagram ◽  
Free Energy ◽  
Elevated Temperature ◽  
Alloy System ◽  
Calphad Method ◽  
Energy Curve ◽  
Negative Deviation ◽  
Alloying Element ◽  
Research Article ◽  
Activity Curve

This research article reports simulations and prediction based calculation for Co-Fe system under the application of Calphad method and thermocalc package. At different elevated temperature of 1200k, 1225k 1nd 1250k the said system is modeled and corresponding behavior of Gibbs free energy, phase diagram and activity curve is monitored. As per calculation the Gibbs energy curve is correspond to its negative era which shows the actual stability application of the said alloy system. The alloying element shows strong interaction amongst which results negative deviation from Roults law in activity era. At 1250k the activity value becomes maximum with same negative deviation. This shows the applicability and reliability of the said alloy system.

scholarly journals Modeling, Simulations, Predictions, Calculations and Thermodynamic Assessments of Cobalt-Ferric Binary Alloys System Using Calphad Method and Pbine Database

2020 ◽  
pp. 3-6
Author(s):  
Shah Waseem Ullah ◽  
Dil Faraz khan ◽  
Shahzeb Burki ◽  
Mohib Ullah Khan ◽  
Haiqing Yin
Keyword(s):  
Phase Diagram ◽  
Free Energy ◽  
Elevated Temperature ◽  
Alloy System ◽  
Calphad Method ◽  
Energy Curve ◽  
Negative Deviation ◽  
Alloying Element ◽  
Research Article ◽  
Activity Curve

This research article reports simulations and prediction based calculation for Co-Fe system under the application of Calphad method and thermo-calc package. At different elevated temperature of 1200k, 1225k 1nd 1250k the said system is modeled and corresponding behavior of Gibbs free energy, phase diagram and activity curve is monitored. As per calculation the Gibbs energy curve is correspond to its negative era which shows the actual stability application of the said alloy system. The alloying element shows strong interaction amongst which results negative deviation from Roults law in activity era. At 1250k the activity value becomes maximum with same negative deviation. This shows the applicability and reliability of the said alloy system.

scholarly journals Kinetics and thermodynamic properties related to the drying of 'Cabacinha' pepper fruits

2016 ◽  
Vol 20 (2) ◽  
pp. 174-180 ◽  
Author(s):  
Hellismar W. da Silva ◽  
Renato S. Rodovalho ◽  
Marya F. Velasco ◽  
Camila F. Silva ◽  
Luís S. R. Vale
Keyword(s):  
Experimental Data ◽  
Activation Energy ◽  
Free Energy ◽  
Thermodynamic Properties ◽  
Gibbs Free Energy ◽  
Removal Rate ◽  
Effective Diffusion ◽  
Drying Time ◽  
Three Samples ◽  
Different Temperatures

ABSTRACT The objective of this study was to determine and model the drying kinetics of 'Cabacinha' pepper fruits at different temperatures of the drying air, as well as obtain the thermodynamic properties involved in the drying process of the product. Drying was carried out under controlled conductions of temperature (60, 70, 80, 90 and 100 °C) using three samples of 130 g of fruit, which were weighed periodically until constant mass. The experimental data were adjusted to different mathematical models often used in the representation of fruit drying. Effective diffusion coefficients, calculated from the mathematical model of liquid diffusion, were used to obtain activation energy, enthalpy, entropy and Gibbs free energy. The Midilli model showed the best fit to the experimental data of drying of 'Cabacinha' pepper fruits. The increase in drying temperature promoted an increase in water removal rate, effective diffusion coefficient and Gibbs free energy, besides a reduction in fruit drying time and in the values of entropy and enthalpy. The activation energy for the drying of pepper fruits was 36.09 kJ mol-1.

scholarly journals A Study effect of Substituents X on Methylenecyclopentane and 1- Methylcyclopentene System

2018 ◽  
Vol 1 (1) ◽  
pp. 38-44
Author(s):  
Ghassab Al-Mazaideh
Keyword(s):  
Free Energy ◽  
Dft Calculations ◽  
Gibbs Free Energy ◽  
Free Energy Calculations ◽  
Relative Stabilities ◽  
Energy Calculations ◽  
Effect Of Substituents ◽  
Orbital Energies ◽  
The Stability ◽  
Homo Lumo

In this study, the geometry optimizations, orbital energies (HOMO-LUMO) and relative stabilities of methylene cyclopentane and 1-methylcyclopentene were investigated by DFT calculations. 1-methylcyclopentene was found to be more stable than methylene cyclopentane isomer with enthalpy value H=18.518 kJ/mol. Also, the effect of substituents X (F, OH, CH3, NH2, CN, NO2, CHO and CF3) also studied on the relative stabilities of these two tautomers. The results showed that the stability of both isomers is increased by all substitutes. Gibbs free energy calculations have been used to find the effect of substituents X on the system.

Modeling of the Thermodynamic Properties of Liquid Fe-Ni and Fe-Co Alloys From the Surface Tension Data

2011 ◽  
Vol 56 (1) ◽  
pp. 13-23 ◽  
Author(s):  
W. Gąsior ◽  
P. Fima ◽  
Z. Moser
Keyword(s):  
Surface Tension ◽  
Free Energy ◽  
Surface Layer ◽  
Thermodynamic Properties ◽  
Gibbs Free Energy ◽  
Thermodynamic Data ◽  
Excess Gibbs Free Energy ◽  
Surface Tension Data ◽  
Co Alloys ◽  
Good Agreement

Modeling of the Thermodynamic Properties of Liquid Fe-Ni and Fe-Co Alloys From the Surface Tension DataRecently proposed method of modeling of thermodynamic properties of liquid binary alloys from their surface tension data is described. The method utilizes Melford and Hoar equation, relating surface tension with excess Gibbs free energy, combined with new description of the monatomic surface layer and β parameter. The method is tested on Fe-Ni and Fe-Co alloys and the obtained results show very good agreement with experimental thermodynamic data of other authors. The model allows also to calculate the surface tension from thermodynamic data, and it gives better agreement with experimental results than those modeled with the use of Butler equation and traditionally defined monatomic surface layer and β = 0.83.

Thermodynamics of Organic Dyes Adsorption onto Thermal Modified Rectorite

2012 ◽  
Vol 463-464 ◽  
pp. 194-197
Author(s):  
Jing Yan Song ◽  
Ling Rong He
Keyword(s):  
Free Energy ◽  
Gibbs Free Energy ◽  
Organic Dyes ◽  
X Ray Diffraction ◽  
Adsorption Interaction ◽  
Equilibrium Data ◽  
Different Temperatures ◽  
Hoff Equation ◽  
Dyes Adsorption ◽  
Langmuir And Freundlich Equations

Adsorption behavior of Rhodamine B (RhB) onto thermal modified rectorite (TM-R) has been thermodynamically investigated. The thermal modified rectorite prepared at different temperatures was characterized by X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET). The analysis of the isotherm equilibrium data using the Langmuir and Freundlich equations by linear methods showed that the data fitted better with Freundlich model than the Langmuir model. Thermodynamic parameters were calculated based on Van’t Hoff equation. The average change of standard adsorption heat of RhB was 88.96 kJ/mol. The adsorption Gibbs free energy changes are in the range of -26.88～-34.52 kJ/mol, The negative of adsorption Gibbs free energy changes in all cases are indicative of the spontaneous nature of the adsorption interaction, and the values of adsorption entropy changes are positive.

scholarly journals Enzymatic Kinetic Issues and Controversies Surrounding Gibbs Free Energy of Activation and Arrhenius Activation Energy

2020 ◽  
pp. 1-13
Author(s):  
Ikechukwu I. Udema ◽  
Abraham Olalere Onigbinde
Keyword(s):  
Activation Energy ◽  
Free Energy ◽  
Equilibrium Constant ◽  
Gibbs Free Energy ◽  
Theoretical Research ◽  
Energy Of Activation ◽  
Arrhenius Activation Energy ◽  
Free Energy Of Activation ◽  
Different Temperatures ◽  
The Difference

Background: The equation of the difference between reverse and forward Gibbs free energy of activation (ΔΔGES#) reflects Michaelis-Menten constant (KM) in both directions; this may not be applicable to all enzymes even if the reverse reaction is speculatively Michaelian. Arrhenius activation energy, Ea and (Ea - ΔGES#)/RT) are considered = ΔGES# and KM respectively. The equations are considered unlikely. Objectives: The objectives of this research are: 1) To derive what is considered as an appropriate equation for the determination of the difference in ΔGES# between the reverse and forward directions, 2) calculate the difference between the reverse and total forward ΔGES#, and 3) show reasons why Ea ≠ ΔGES#  in all cases. Methods: A major theoretical research and experimentation using Bernfeld method. Results and Discussion: A dimensionless equilibrium constant KES is given. Expectedly, the rate constants were higher at higher temperatures and the free energy of activation with salt was < the Arrhenius activation energy, Ea; ΔΔGES#ranges between 67 - 68 kJ/mol. Conclusion: The equations for the calculation of the difference in free energy of activation (ΔΔGES#) between the forward and reverse directions and a dimensionless equilibrium constant for the formation of enzyme-substrate (ES) were derivable. The large positive value of the ΔΔGES# shows that the forward reaction is not substantially spontaneous; this is due perhaps, to the nature of substrate. The equality of Arrhenius activation energy (Ea) and ΔGES# may not be ruled out completely but it must not always be the case; the presence of additive like salt can increase the magnitude of Ea well above the values of the ΔGES#. A dimensionless equilibrium constant for the net yield of ES seems to be a better alternative than KM. The Ea unlike ΔGES#  requires at least two different temperatures for its calculation.

scholarly journals Evaluation of Stoichiometry, Stability Constants and Gibbs Free Energies of Acetaminophen-Zn (II) complex at Different Temperatures

2020 ◽  
Vol 24 (7) ◽  
pp. 1137-1143
Author(s):  
O.V. Ikpeazu ◽  
I.E. Otuokere ◽  
K.K. Igwe
Keyword(s):  
Free Energy ◽  
Stability Constant ◽  
Gibbs Free Energy ◽  
Stability Constants ◽  
Continuous Variation ◽  
Variation Method ◽  
Ratio Method ◽  
Free Energies ◽  
Different Temperatures ◽  
Continuous Variation Method

Acetaminophen also known as paracetamol, is a drug used in the treatment of pain and fever. It is essentially used for the relief of mild to moderate pain. The presence of phenol and carbonyl oxygen atom enables acetaminophen to behave as a bidentate ligand. The stoichiometry, stability constants and Gibbs free energies of acetaminophen-Zn (II) were determined colorimetrically at 25 and 40 oC using continuous variation and mole  ratio methods. The formation of Zn (II) complex with acetaminophen was studied colorimetrically at an absorption maximum of 630 nm at different temperatures. The data showed that Zn (II) and acetaminophen combine in the molar ratio of 1:1 at pH 7.4 with ionic strength maintained using 0.1M KNO3. Calculated stability constants values were 2.70 x 103 and 2.20 x 103 using continuous variation method and 7.21 x 103 and 7.21 x 103 using mole ratio methods at 25 and 40 oC respectively. Calculated ΔGƟ for the complex were - 1.96 x 104 and -1.98 x 104 J using continuous variation method and -2.2 x 104 J and - 2.31 x 104 J using mole ratio method at 25 and 40 oC respectively. The stability constant and Gibbs free energy results suggested that acetaminophen used in the study is a good chelating agent and can be an efficient antidote in the therapy of Zn (II) overload or poisoning. Keywords: Acetaminophen, Zinc, complex, stability constant, Gibbs free energy.

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