The Establishment of Thermodynamic Model for Ti Bearing Steel-Slag Reaction and Discuss

A thermodynamic model for seven CaO-MgO-BaO-CaF2-SiO2-Al2O3-TiO2 ladle slags based on the Ion and Molecule Coexistence theory (IMCT) is establishment and validated by the experiment results at 1873K. The calculated activity of SiO2, Al2O3 and TiO2 in the slag can be approved by the experiment results and the IMCT model used in this study is reasonable. Then the influence factors such as the mass ratio of CaO to SiO2 (C/S ratio) ranging from 1 to 10, the mass ratio of CaO to Al2O3 (C/A ratio) ranging from 1 to 2.5, TiO2 content (wt pct) ranging from 0 to 30, BaO content (wt pct) ranging from 0 to 30 are investigated based on the thermodynamic calculating results. The raise of C/S ratio, TiO2 content and BaO content in the slag can increase the molar Gibbs energy change (ΔG) of Ti reacted with SiO2 and Al2O3 or Al reacted with SiO2. The effect of C/A ratio on the molar Gibbs energy change (ΔG) of Ti reacted with SiO2 and Al2O3 or Al reacted with SiO2 was less. Finally, the slag with higher C/S ratio and TiO2 content and appropriate BaO content can weaken the reaction between Ti and SiO2 or Al2O3 in the slag.

Eccentricity energy change of complete multipartite graphs due to edge deletion

The eccentricity matrix ɛ(G) of a graph G is obtained from the distance matrix of G by retaining the largest distances in each row and each column, and leaving zeros in the remaining ones. The eccentricity energy of G is sum of the absolute values of the eigenvalues of ɛ(G). Although the eccentricity matrices of graphs are closely related to the distance matrices of graphs, a number of properties of eccentricity matrices are substantially different from those of the distance matrices. The change in eccentricity energy of a graph due to an edge deletion is one such property. In this article, we give examples of graphs for which the eccentricity energy increase (resp., decrease) but the distance energy decrease (resp., increase) due to an edge deletion. Also, we prove that the eccentricity energy of the complete k-partite graph Kn 1, ... , nk with k ≥ 2 and ni ≥ 2, increases due to an edge deletion.

Kinetic and Thermodynamic Studies of Lysozyme Adsorption on Cibacron Blue F3GA Dye-Ligand Immobilized on Aminated Nanofiber Membrane

The polyacrylonitrile (PAN) nanofiber membrane was prepared by the electrospinning technique. The nitrile group on the PAN nanofiber surface was oxidized to carboxyl group by alkaline hydrolysis. The carboxylic group on the membrane surface was then converted to dye affinity membrane through reaction with ethylenediamine (EDA) and Cibacron Blue F3GA, sequentially. The adsorption characteristics of lysozyme onto the dye ligand affinity nanofiber membrane (namely P-EDA-Dye) were investigated under various conditions (e.g., adsorption pH, EDA coupling concentration, lysozyme concentration, ionic strength, and temperature). Optimum experimental parameters were determined to be pH 7.5, a coupling concentration of EDA 40 μmol/mL, and an immobilization density of dye 267.19 mg/g membrane. To understand the mechanism of adsorption and possible rate controlling steps, a pseudo first-order, a pseudo second-order, and the Elovich models were first used to describe the experimental kinetic data. Equilibrium isotherms for the adsorption of lysozyme onto P-EDA-Dye nanofiber membrane were determined experimentally in this work. Our kinetic analysis on the adsorption of lysozyme onto P-EDA-Dye nanofiber membranes revealed that the pseudo second-order rate equation was favorable. The experimental data were satisfactorily fitted by the Langmuir isotherm model, and the thermodynamic parameters including the free energy change, enthalpy change, and entropy change of adsorption were also determined accordingly. Our results indicated that the free energy change had a negative value, suggesting that the adsorption process occurred spontaneously. Moreover, after five cycles of reuse, P-EDA-Dye nanofiber membranes still showed promising efficiency of lysozyme adsorption.

dGPredictor: Automated fragmentation method for metabolic reaction free energy prediction and de novo pathway design

Group contribution (GC) methods are conventionally used in thermodynamics analysis of metabolic pathways to estimate the standard Gibbs energy change (ΔrG′o) of enzymatic reactions from limited experimental measurements. However, these methods are limited by their dependence on manually curated groups and inability to capture stereochemical information, leading to low reaction coverage. Herein, we introduce an automated molecular fingerprint-based thermodynamic analysis tool called dGPredictor that enables the consideration of stereochemistry within metabolite structures and thus increases reaction coverage. dGPredictor has comparable prediction accuracy compared to existing GC methods and can capture Gibbs energy changes for isomerase and transferase reactions, which exhibit no overall group changes. We also demonstrate dGPredictor’s ability to predict the Gibbs energy change for novel reactions and seamless integration within de novo metabolic pathway design tools such as novoStoic for safeguarding against the inclusion of reaction steps with infeasible directionalities. To facilitate easy access to dGPredictor, we developed a graphical user interface to predict the standard Gibbs energy change for reactions at various pH and ionic strengths. The tool allows customized user input of known metabolites as KEGG IDs and novel metabolites as InChI strings (https://github.com/maranasgroup/dGPredictor).

ԼՐԻՎ ՄԵԽԱՆԻԿԱԿԱՆ ԷՆԵՐԳԻԱՅԻ ՓՈՓՈԽՈՒԹՅԱՆ ԹԵՈՐԵՄԻ ԵՎ ՄՈՄԵՆՏՆԵՐԻ ԿԱՆՈՆԻ ՄԵԿ ՀԱՄԱՏԵՂ ԿԻՐԱՌՈՒԹՅԱՆ ՄԱՍԻՆ / ON THE JOINT APPLICATION OF A FULL MECHANICAL ENERGY CHANGE THEOREM AND THE RULES OF MOMENTS

Աշխատանքը նվիրված է ֆիզիկայի դպրոցական դասընթացում լրիվ մեխանիկական էներգիայի փոփոխության թեորեմի և մոմենտների կանոնի հնարավոր համատեղ կիրառությունների վերհանմանըֈ Դիտարկված է կոնկրետ խնդիր, որի շրջանակում վերոգրյալ երկու կանոների կիրառման արդյունքում հնարավոր է դառնում որոշել համասեռ շրջանագծային աղեղի զանգվածի կենտրոնըֈ Խնդրի շրջանակում ստացված արդյունքն ընդհանրացվել է կամայական կենտրոնային անկյունով համասեռ շրջանաձև աղեղի համարֈ: / The work is devoted to identifying possible joint applications of the rule of moments and the theorem for changing the total mechanical energy in a school physics course. A specific problem is considered, within the framework of which, as a result of the application of the above two rules, it becomes possible to determine the center of mass of a uniform circular arc. The result obtained in the framework of the problem is generalized to a homogeneous circular arc with an arbitrary central angle.

Free Energy Change during the Formation of Crystalline Contact between Lysozyme Monomers under Different Physical and Chemical Conditions

We use the MM/GBSA method to calculate the free energies of dimer formation by binding two monomers with different combinations of precipitant ions, both embedded in the structure of monomers and in the crystallization solution. It shows that the largest difference in free energy values corresponds to the most accurate dimer model, which considers all precipitant ions in their structure. In addition, it shows that in the absence of precipitant ions in the solution of lysozyme molecules, a monomer is a more energetically favorable state.

Determining the Most Stable Structure of Benzamided Derivatives Using Density Functional Theory (DFT)

This study aims to determine the energy change ∆E and determine the most stable compound based on computation results using the Density Functional Theory (DFT) method. In determining the energy change ∆E and determining the most stable compound, computational chemical calculations were used using NWChem version 6.6 software with the DFT method with the B3LYP / 3-21G base set hybrid function, the results of the calculations were visualized using the Jmol software. The results of computational calculations on the compound Benzamide is 57467.3632844735 kJ / mol, (4 - chlorocarbonyl - benzial) - pyridine acid carbamics - 3 - ilmetyl ester is 641022.0125237265 kJ / mol, (4- phenylcarbamil benzyl) - pyridine acid carbamic - 3 - ilmetyl ester of 491144.0953277345 kJ / mol, [4- (2-nitro - phenyl carbamoyl) - benzyl] - pyridine acid carboxy - 3 - ilmetyl ester of 1031145,366027853 kJ / mol while for [4 - 2 (amino - phenyl carbamyl) - benzyl) - carboxylic acid - 3 - ilmetyl ester of -1034711.17423932 kJ / mol. Based on these data it can be concluded that [4 - 2 (amino - phenyl carbamyl) - benzyl) - carboxylic acid - 3 - ilmetyl ester is the most stable compound formed because of its lowest price (exothermic)

Energy of a magnetic body: −m⋅δB or +B⋅δm?

“Energy of a magnetic body: -m dB or +B dm?” addresses a fraught question: what is the free-energy change when a B-field applied to a magnetic body (magnetic moment m) is changed? We define what is meant by an “applied field”. We show that the free-energy change is -m dB. The electric analogue -p dE is also described. A balls-and-spring model helps to understand an electric dipole, and by extension a magnetic dipole. In the magnetic case, we prepare the field using a reversible current generator driving a coil. The energy change is obtained by inserting the sample and (also, alternatively) by changing the field. There is much that is new in this chapter.