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This paper aims to synthesise and characterise N-cyclohexylmethacrylamide (NCMA) monomer which contains thermosensitive group. The characterisation of monomer was performed both theoretically and experimentally.

The monomer was prepared by reacting cyclohexylamine with methacryloyl chloride in the presence of triethylamine at room temperature. The synthesised monomer was characterised by using not only Density Functional Theory (DFT) and Hartree–Fock (HF) with the Gaussian 09 software but also fourier transform infrared (FT–IR), ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy.

Both the experimental and the theoretical methods demonstrated that the monomer was successfully synthesised. The vibrational frequencies, the molecular structural geometry, such as optimised geometric bond angles, bond lengths and the Mulliken atomic charges of NCMA were investigated by using DFT/B3LYP and HF methods with the 3-21G* basis set. The experimental results were compared with theoretical values. The results revealed that the calculated frequencies were in good accord with the experimental values. Besides, frontier molecular orbitals (FMOs) and molecular electrostatic potential of NCMA were investigated by theoretical calculations at the B3LYP/3–21G* basis set.

Monomer and polymer containing a thermosensitive functional group have attracted great interest from both industrial and academic fields. Their characterisation can provide great opportunities for polymer science by using DFT and HF methods.

The monomer containing a thermosensitive functional group and a various polymer may be prepared by using DFT and HF methods described in this paper. The calculated data are greatly important to provide insight into molecular analysis and then used in technological applications.

This study aimed the synthesis and theoretical/experimental characterization of novel benzofuran-based acrylamide monomer.

Novel N-substituted acrylamide monomer, i.e. N-[2–(4-Bromo-benzoyl)-benzofuran-3-yl]-acrylamide (BBFA), was synthesized by reacting (3-Amino-benzofuran-2-yl)-(4-bromophenyl) methanone with acryloylchloride at 0–5^oC. Nuclear magnetic resonance (1H-NMR), infrared (FT-IR) and UV-Visible spectrophotometer were used to elucidate the chemical structure of BBFA. Computational studies were performed using the DFT (B3LYP) method on the basis of 6-31 + G (d, p) using Gaussian 09 W and Gauss View 5.0 package in addition to the VEDA program, gauge-independent atomic orbital (GIAO) and time-dependent density functional theory (TD-DFT) methods.

Molecular geometry and vibration assignments of the BBFA monomer were calculated. The molecular structure of the monomer was examined. Both longest and shortest bonds were determined in the structure. The nucleophilic and electrophilic regions of the monomer were determined. The theoretical spectroscopic data of the monomer were compared with the experimental data; both were consistent with each other. The chemical reactivity of the monomer was also determined.

The synthesized BBFA monomer can be evaluated in many areas; from medicine to industry (such as textiles) owing to the presence of various active functional groups. Indeed, acrylamide copolymers are remarkable materials for polymer science and industry. The data produced in this study is original and adds to the scientific community.

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely, 1-((1-((2,2,7,7-tetramethyltetrahydro-5H-bis([1,3]dioxolo)[4,5-b:4′,5′-d]pyran-5-yl)methyl)-1H-1,2,3-triazol-4-yl)methyl)-1H-benzo[d]imidazole (TTB) on the corrosion of mild steel in aerated 1 M H₂SO₄.

The authors have used weight loss measurement, potentiodynamic polarization, electrochemical impedance spectroscopy, FT-IR studies, scanning electron microscopy analysis and energy dispersive X-ray (EDX) spectroscopy techniques.

It is found that, in the working range of 298-328 K, the inhibition efficiency of TTB increases with increasing concentration to attain the highest value (92 per cent) at 2.5 × 10⁻³ M. Both chemisorption and physisorption of TTB take place on the mild steel, resulting in the formation of an inhibiting film. Computational methods point to the imidazole and phenyl ring as the main structural parts responsible of adsorption by electron-donating to the steel surface, while the triazol ring is responsible for the electron accepting. Such strong donating–accepting interactions lead to higher inhibition efficiency of TTB in the aqueous working system.

This work is original with the aim of finding new acid corrosion inhibitors.

Paper aims to preparation of new acid disperse dyes based on thiadiazol derivatives and evaluation of their use as antimicrobial colorants in digital transfer-printing ink formulations for printing onto polyester fabric substrates.

New disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) were prepared and evaluated by different analysis then formulated as colored materials in the ink formulations. The viscosity, dynamic surface tension and particle size distribution of the prepared inks were measured. The printed polyester fabric substrates were tested using a variety of tests, including light fastness, washing, alkali perspiration and Crock fastness, as well as depth of penetration. Density-functional theory (DFT) calculations were carried out at the Becke3-Lee-Yang-parr (B3LYP) level using the 6–311** basis set, and the biological activity of the prepared disperse dyes was investigated.

The obtained results of the physical of the prepared ink revealed that thiadiazol disperse ink is a promising ink formulation for polyester printing and agrees with the quality of the printed polyester fabric. The optimization geometry for molecular structures agreed with the analysis of these compounds. The HOMO/LUMO and energy gap of the studied system were discussed. The molecular docking analysis showed strong interaction with DNA Gyrase and demonstrated to us the high ability of these inks to act as antimicrobial agents.

The prepared inks containing the prepared thiadiazol disperse dye were high-performance and suitable for this type of printing technique, according to the results. The prepared inks resist the growth of microorganisms and thus increase the ink's storage stability.

The prepared disperse dyes based on 1,3,4 - thiadiazol derivative (dyes 1–3) can be a promising colorant in different applications, like some types of paint formulations and as a colorant in printing of different fabric substrates.

The purpose of this paper is to minimize corrosion-related pollution in the environment. From the lemongrass extract (LGE), the authors selected one of the best green inhibitors.

The corrosion and inhibition of mild steel in traditional acidification solutions were estimated by electrochemical measurements. The corrosion appearance was observed with scanning electron microscopy, atomic force microscopy micrographs and attenuated total reflectance infrared spectroscopy spectrum. The correlation was formed between the gained inhibition efficiency (IE)% from electrochemical measurements and certain quantum chemical parameters.

The results displayed that the IE was up to 90% when the LGE concentration was 300 ppm. The results confirmed that the theoretical experiments are very similar to the experimental observations.

For the first time, LGE was used as a cheap and safe corrosion inhibitor for mild steel corrosion in the acidification process. The mechanism of mild steel corrosion and anti-corrosion in acid solution has been suggested.

This paper aims to study the inhibition effect of 2-pyridinealdazine on the corrosion of mild steel in an acidic medium. The inhibition effect was studied using weight loss, electrochemical impedance spectroscopy, and Tafel polarization measurements.

Weight loss measurements, potentiodynamic tests, electrochemical impedance spectroscopy, X-ray diffraction and spectral and conformational isomers analysis of A (E-PAA) and B (Z-PAA) were performed were investigated.

2-pyridinealdazine (PAA) acts as a good inhibitor for the corrosion of steel in 2.0 M H₃PO₄. The inhibition efficiency increases with an increase in inhibitor concentration but decreases with an increase in temperature.

This paper is intended to be added to the family of azines which are highly efficient inhibitors and can be used in the area of corrosion prevention and control.

This paper aims to study inhibitory effect of 4-aminothiophenol on the corrosion of mild steel (MS) in 0.5 M HCl.

In this study, electrochemical experiments, quantum chemical calculations, potentiodynamic measurements, linear polarization resistance and scanning electron microscopy were used.

The experimental results suggest that this compound is efficient corrosion inhibitor and the inhibition efficiencies increase with increasing their (from 0.5 to 10.0 mM.) concentrations. This reveals that inhibitive actions of inhibitors were mainly due to adsorption on mild steel surface. The adsorption of these inhibitors was found to obey Langmuir adsorption model. The computed quantum chemical features show good correlation with empirical inhibition efficiencies.

The 4-aminothiophenol is suitable inhibitor for application in closed-circuit systems against corrosion. The study is original and has great impact in industrial area. The obtained theoretical results have been adapted with the experimental data.

This paper aims to prepare a new donor–π–acceptor (D–π–A) and acceptor–π– D–π–A (A–π–D–π–A) phenothiazine (PTZ) in conjugation with vinyl isophorone (PTZ-1 and PTZ-2) were designed and their molecular shape, electrical structures and characteristics have been explored using the density functional theory (DFT). The results satisfactorily explain that the higher conjugative effect resulted in a smaller high occupied molecular orbital–lowest unoccupied molecular orbital gap (Eg). Both compounds show intramolecular charge transfer (ICT) transitions in the ultraviolet (UV)–visible range, with a bathochromic shift and higher absorption oscillator strength, as determined by DFT calculations.

The produced PTZ-1 and PTZ-2 sensors were characterized using various spectroscopic methods, including Fourier-transform infrared spectroscopy and nuclear magnetic resonance spectroscopy (¹H/¹³CNMR). UV–visible absorbance spectra of the generated D–π–A PTZ-1 and A–π–D–π–A PTZ-2 dyes were explored in different solvents of changeable polarities to illustrate positive solvatochromism correlated to intramolecular charge transfer.

The emission spectra of PTZ-1 and PTZ-2 showed strong solvent-dependent band intensity and wavelength. Stokes shifts were monitored to increase with the increase of the solvent polarity up to 4122 cm⁻¹ for the most polar solvent. Linear energy-solvation relationship was applied to inspect solvent-dependent Stokes shifting. Quantum yield (ф) of PTZ-1 and PTZ-2 was also explored. The maximum UV–visible absorbance wavelengths were detected at 417 and 419 nm, whereas the fluorescence intensity was monitored at 586 and 588 nm.

The PTZ-1 and PTZ-2 dyes leading to colorimetric and emission spectral changes together with a color shift from yellow to red.

The purpose of this study aims to synthesize a novel donor–acceptor dye based on phenothiazine as a donor (D) and nonconjugated spacer was devised and synthesized by condensing of 2,2'-(1H-indene-1,3(2H)-diylidene) dimalononitrile with aldehyde and the practical synthesis methodology as given in Scheme 1.

The prepared phenothiazine dye was systematically experimentally and theoretically examined and characterized using nuclear magnetic resonance spectroscopy (1H,13C NMR), Fourier-transform infrared spectroscopy (IR) and high-resolution mass spectrometry. Density functional theory (DFT) and time-dependent density functional theory DT-DFT calculations were implemented to determine the electronic properties of the new dye

The UV-Vis absorption and fluorescence spectroscopy of the synthesized dye was investigated in a variety of solvents with varying polarities to demonstrate positive solvatochromism correlated with intramolecular charge transfer (ICT). The probe’s quantum yields (Фf) are experimentally measured in ethanol, and the Stokes shifts are found to be in the 4846–9430 cm⁻¹ range.

The findings depicted that the novel (D-π-A) chromophores may act as a significant factor in the organic optoelectronics.

The purpose of this is to study the mechanism of an oil film thickness formation in the nanoscale. A polar lubricant of propylene carbonate is used as the intervening liquid between contiguous bodies in concentrated contacts. A pressure caused by the hydrodynamic viscous action in addition to the double-layer electrostatic force, van der Waals inter-molecular forces and solvation pressure owing to inter-surface forces is considered when calculating the ultrathin lubricating films.

Using the Newton–Raphson iteration technique applied for the convergence of the hydrodynamic pressure, a numerical solution has been ascertained.

The results show that, at separations beyond about five molecular diameters of the intervening liquid, the formation of a lubricant film thickness is governed by the combined effects of viscous action and surface force of an attractive van der Waals force and a repulsive double-layer force. At smaller separations below five molecular diameters of the intervening liquid, the effect of the solvation force is dominant in determining the oil film thickness.

This paper fulfils an identified need to study the behavior of polar lubricants in concentrated contacts in ultrathin conjunctions. The effect of the hydrodynamic action, electrostatic force and surface action of van der Waals and solvation forces is considered when calculating the lubricant oil film thickness.