Search results
1 – 10 of 84
This study aimed the synthesis and theoretical/experimental characterization of novel benzofuran-based acrylamide monomer.
Abstract
Purpose
This study aimed the synthesis and theoretical/experimental characterization of novel benzofuran-based acrylamide monomer.
Design/methodology/approach
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 0–5oC. 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.
Findings
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.
Originality/value
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.
Details
Keywords
Xuejun Xie, Ling Pang, Shunan Cao, Wanqin Yang, Min Yan, Xunjie Gong and Keru Peng
The purpose of this paper is to present a study of corrosion inhibition of carbon steel in hydrochloric acid by some benzene nitriles using the quantum chemistry calculation.
Abstract
Purpose
The purpose of this paper is to present a study of corrosion inhibition of carbon steel in hydrochloric acid by some benzene nitriles using the quantum chemistry calculation.
Design/methodology/approach
The molecular structure and inhibition mechanism, and the relationship between inhibition efficiency of some benzene nitriles on carbon steel in the hydrochloric acid, were studied from a microcosmic viewpoint using the quantum chemistry calculation.
Findings
The calculation results showed that the inhibition efficiency of benzene nitriles on carbon steel in hydrochloric acid could be expressed by σN and ELUMO, and the greater σN absolute value and the lesser the value of ELUMO, then the greater the efficiency of the inhibitor. The regression equation for benzene nitriles is: η=2.665056−0.4447122ELUMO−10.92817σN r=0.9953128.
Originality/value
The paper offers insights into the application of the quantum chemistry calculation.
Details
Keywords
Xie Xuejun, Cao Shunan, Pan Ling, Gong Xunjie and Peng Keru
The inhibition mechanism and the relationship between the inhibition efficiency of para‐chlorobenzene nitriles on carbon steel in hydrochloric acid, and their molecular structure…
Abstract
The inhibition mechanism and the relationship between the inhibition efficiency of para‐chlorobenzene nitriles on carbon steel in hydrochloric acid, and their molecular structure, were studied by microscopy and quantum chemistry calculations. The inhibition of carbon steel was achieved by chemisorption of the para‐chlorobenzene nitriles onto the surface of the carbon steel. The greater was the σN (absolute value) and the less the ELUMO value, the greater was the inhibition efficiency.
Details
Keywords
Abstract
Purpose
The purpose of this paper is to focus on the development of highly efficient emission materials for light‐emitting diodes (LEDs).
Design/methodology/approach
The equilibrium geometries of silole‐based derivatives are optimised by means of DFT/B3LYP method with the 6‐31G(d) basis set in this paper. The geometries of single‐excitation are optimised using the ab initio configuration interaction with single excitations/6‐31G(d), the first singlet excited states and optical properties are calculated by using time‐dependent density‐functional theory based on the 6‐31G(d) basis set.
Findings
The highest occupied molecular orbital and lowest unoccupied molecular orbital suffer larger effects from the variation of the substituent groups of methyls and phenyls. The absorption wavelengths of all the cases are similar, but the emission wavelengths are significantly different.
Research limitations/implications
Solid‐state stacking effect is not included in this paper.
Originality/value
In view of the application of silole‐based derivatives systems, the control of photophysical properties and electronic structures by structural modification is relevant to further molecular design.
Details
Keywords
Ali A. Ali, H. Abd El-Wahab, Moustafa S. Abusaif, Ahmed Ragab, Omar A. Abdel-Jaid, E.A. Eldeeb and Yousry A. Ammar
The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full…
Abstract
Purpose
The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.
Design/methodology/approach
The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including EHOMO, ELUMO and optimized geometrical structure, were assumed and discussed in detail.
Findings
The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as EHOMO, ELUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.
Originality/value
This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.
Details
Keywords
Pingo Mutombo and Norman Hackerman
The effect of some organophosphorus compounds on iron corrosion in 6 M HCl has been examined by means of polarization and capacitance measurements. It appears that these compounds…
Abstract
The effect of some organophosphorus compounds on iron corrosion in 6 M HCl has been examined by means of polarization and capacitance measurements. It appears that these compounds inhibit iron corrosion by affecting both cathodic and anodic reactions. A quantum chemical approach was used to correlate the inhibition efficiency to the molecular structure of the compounds. It was found that there is not a noticeable relationship between their molecular structure and their inhibition effectiveness. Also based on these calculations, it can be suggested that the inhibitor molecules behave as electron acceptor when they adsorb on the iron metal.
Details
Keywords
Feride Akman and Nevin Çankaya
This paper aims to synthesise and characterise N-cyclohexylmethacrylamide (NCMA) monomer which contains thermosensitive group. The characterisation of monomer was performed both…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Research limitations/implications
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.
Originality/value
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.
Details
Keywords
Ali A. Ali, Maha Mohammed Elsawy, Salem S. Salem, Ahmed A. El-Henawy and Hamada Abd El-Wahab
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…
Abstract
Purpose
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.
Design/methodology/approach
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.
Findings
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.
Practical implications
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.
Originality/value
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.
Details
Keywords
Fatemeh Mollaamin and Majid Monajjemi
The purpose of this paper is to investigate the ability of transition metals (TMs) of iron-, nickel- and zinc-doped graphene nanosheet for adsorption of toxic gas of nitric oxide…
Abstract
Purpose
The purpose of this paper is to investigate the ability of transition metals (TMs) of iron-, nickel- and zinc-doped graphene nanosheet for adsorption of toxic gas of nitric oxide (NO). The results of this paper have provided a favorable understanding of the interaction between TM-doped graphene nanosheet and NO molecule.
Design/methodology/approach
A high performance of TM-doped graphene nanosheet as a gas sensor is demonstrated by modeling the material’s transport characteristics by means of the Langmuir adsorption and three-layered ONIOM/ density functional theory method. The Langmuir adsorption model has been done with a three-layered ONIOM using CAM-B3LYP functional and LANL2DZ and 6–311G (d, p) basis sets by Gaussian 16 revision C.01 program towards the formation of of NO→TM(Mn, Co, Cu)-doped on the Gr nanosheet.
Findings
The changes of charge density for Langmuir adsorption of NO on Mn-, Co- and Cu-doped graphene nanosheet orderly have been achieved as: ΔQCo-doped = +0.309 >> ΔQMn-doped = −0.074 > ΔQCu-doped = −0.051. Therefore, the number of changes of charge density have concluded a more remarkable charge transfer for Mn-doped graphene nanosheet. However, based on nuclear magnetic resonance spectroscopy, the sharp peaks around Cu doped on the surface of graphene nanosheet and C19 close to junction of N2 and Co17 have been observed. In addition, Cu-doped graphene sheet has a large effect on bond orbitals of C8–Cu 17, C15–Cu 17 and C16–Cu17 in the adsorption of NO on the Cu-doped/Gr which has shown the maximum occupancy. The amounts of
Originality/value
This research aims to explore the adsorption of hazardous pollutant gas of “NO” by using carbon nanostructure doped by “TM” of iron, nickel and zinc to evaluate the effectiveness of adsorption parameters of various TM-doped graphene nanosheets.
Details
Keywords
Abdelaziz S. Fouda, Mohamed A. Ismail, Rabab M. Abou-shahba, Walaa A. Hussein, Esraa S. El-habab and Ashraf S. Abousalem
The purpose of this paper is to investigate three Arylfuranylnicotinamidine derivatives against corrosion of carbon steel (C-steel) in 1.0 M HCl by chemical and electrochemical…
Abstract
Purpose
The purpose of this paper is to investigate three Arylfuranylnicotinamidine derivatives against corrosion of carbon steel (C-steel) in 1.0 M HCl by chemical and electrochemical means. The inhibition efficiency (%IE) increases with increasing the dose of inhibitors. The tested compounds exhibited improved performance at elevated temperature, with %IE reaching 93 percent at 21 µM. Tafel polarization method revealed that the tested compounds act as mixed-type inhibitors. The inhibition action was rationalized due to chemical adsorption of inhibition molecules on C-steel surface following Temkin’s isotherm. Surface examination was carried out by AFM and FTIR techniques. Further, theoretical chemical approaches were used to corroborate the experimental findings.
Design/methodology/approach
Experimental and computational methods were applied to investigate the efficiency of these new compounds. These studies are complemented with spectral studies and surface morphological scan by AFM. The theoretical results indicate good correlation with experimental findings.
Findings
The tested derivatives are promising corrosion inhibitors for C-steel in the acid environment. The molecular scaffold of this class of compounds can be used to design new highly efficient inhibitors by screening its activity by modeling studies.
Originality/value
The studied compounds are safe inhibitors and greatly adsorbed on Fe surface. The action of compounds is enhanced with temperature, which means these compounds can be used in higher temperature systems. The new compounds are effective at very low concentration.
Details