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CVD (chemical vapor deposition) coatings such as TiC, TiN, Al₂O₃ and so on are widely used as tools' surface preserved materials with corrosion resistance and wear resistance. Standard Gibbs free energy changes for reactions are widely used to approximately analyze the trends of substance reactions and phase transitions in chemical reactions, metallurgy processes, materials synthesis and processing. Hard coatings and thin films can be prepared by CVD process. Accurate calculation and plotting of the standard free energy changes and equilibrium constants for CVD TiC, TiN, Al₂O₃ coatings reactions are realized using the developed general computer program. Only inputting the basic thermodynamic data tabulated in data books into the computer program, the relationships of the standard free energy changes and equilibrium constants for most reactions with the temperatures can be gained in the same diagrams.

The thermodynamic integration/path integral Monte Carlo (TI/PIMC) method of calculating the temperature dependence of the equilibrium constant quantum mechanically is applied to O + HCl ⇌ OH + Cl reaction. The method is based upon PIMC simulations for energies of the reactants and the products and subsequently on thermodynamic integration for the ratios of partition functions. PIMC calculations are performed with the primitive approximation (PA) and the Takahashi–Imada approximation (TIA).

The UV-visible spectrum of free-base octaethylcorrole, (OECor)H₃, was recorded in thirteen different nonaqueous solvents as well as in a mixed acetonitrile/acid solvent containing one of seven different acids. Spectra were also measured in seven different solutions of neat concentrated acid and in CH₃CN containing piperidine or tetrabutylammonium hydroxide as an added base. The overall data was analyzed as a function of solvent acidity or basicity parameters and the number of protons on the central nitrogens of the macrocycle, the predominant form of the corrole in these solutions being respresented as (OECor)H₃, [(OECor)H₄]⁺, [(OECor)H₂]⁻ or [(OECor)H]²⁻ where OECor = trianion of octaethylcorrole. The mono-protonated corrole, [(OECor)H₄]⁺, is formed in concentrated acetic acid or in CH₃CN containing 0.10 M trifluoroacetic acid, H₂SO₄, HCl, H₃PO₄ or HClO₄. The mono-deprotonated corrole, [(OECor)H₂]⁻, is generated in piperidine while doubly deprotonated [(OECor)H]²⁻ exists in solutions of tetrabutylammonium hydroxide. An addition of protons to the macrocycle of [(OECor)H₄]⁺ also occurs in the presence of concentrated strong acids and this results in a loss of the characteristic Soret band of the corrole leading presumably to [(OECor)H₅]²⁺ where the second proton has been added to a meso-position of the macrocycle. The UV-visible spectral changes upon formation of [(OECor)H₄]⁺, [(OECor)H₂]⁻ or [(OECor)H]²⁻ in CH₃CN were monitored during a titration with the relevent acid or base and equilibrium constants for protonation or deprotonation of (OECor)H3 were determined using standard equations. The measured logK values are compared to protonation and deprotonation constants obtained for two related corroles and two related porphyrins under the same experimental conditions.

The aggregation of 85 porphyrin derivatives and a report on a kinetic and thermodynamic study of such aggregation behavior on varying the derivatives of porphyrin was carried out using molecular dynamics simulation and Docking. Distance diagrams of simulated compounds were obtained and decrease of curves is a clear evidence of the aggregation. Aggregation rates were studied by origin software. In order to calculate interaction energies of derivatives, compounds were docked and the equilibrium constant of porphyrin-porphyrin interaction were obtained. Quantitative Structure-Property Relationship (QSPR) studies were performed for the sets of 85 Porphyrin derivatives. Multiple Linear Regression method (MLR) and Principal Component Analysis (PCA) were used and resulted in useful models with good prediction ability. This models were able to predict the kinetic and equilibrium constant for all sets of our compounds. The correlation coefficients for prediction of rate and logarithm of equilibrium constants were 0.67 and 0.97 by MLR method respectively and 0.90 for prediction of equilibrium constant by PCA analyses. In order to have a better prediction, compounds were divided into two groups, oxygenated and non-oxygenated group and correlation coefficient for prediction of rate constants of them were obtained 0.89 and 0.94 by MLR model respectively. Results of structure-property relationship showed that, larger, more hydrophobe and more planner derivatives have higher aggregation rate.

Most of the previous artificial oxygen carriers realized the oxygen-carrying function through a reversible combination of penta-coordinated iron(II) porphyrin with oxygen. The other oxygen transport model, in which oxygen competes with other ligands for binding with central ions, has been rarely studied. In this study, oxygen-carrying properties of a series of hexa-coordinated complexes were investigated, with heme dimethyl ester working as an oxygen-carrying component. In addition, both oxygen uptake and the auto-oxidation rate of the hexa-coordinated complexes were also explored. The results indicate that the hexa-coordinated complexes can effectively carry oxygen, provided that there is at least one strong ligand on the fifth or sixth coordination site of the heme dimethyl ester. Promisingly, when one ligand is strong and the other ligand is weak, the hexa-coordinated complexes can exhibit highly efficient oxygen-carrying capacity. By fixing weak ligands and changing strong ligands, it was found that the coordination ability of strong ligands has a significant impact on the oxygenation curve of the system. Furthermore, the auto-oxidation rate of the hexa-coordinated complexes of heme dimethyl ester is related to the hydrophobicity of the fifth and sixth ligands. The longer the hydrophobic chain of the ligand, the slower the auto-oxidation rate. Consequently, the oxygen-binding mode of this heme derivative has the potential to be an effective oxygen carrier.

We saw (Section 4.4) that CO₂ (carbon dioxide) reacts with quicklime (calcium oxide) in water at 25°C, under 1 atm generating calcium carbonate or limestone (CaCO₃). The process is a sequence of two reactions (4.14) and (6.1):