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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.

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.

The calculation results showed that the inhibition efficiency of benzene nitriles on carbon steel in hydrochloric acid could be expressed by σ_N and E_LUMO, and the greater σ_N absolute value and the lesser the value of E_LUMO, then the greater the efficiency of the inhibitor. The regression equation for benzene nitriles is: η=2.665056−0.4447122E_LUMO−10.92817σ_N r=0.9953128.

The paper offers insights into the application of the quantum chemistry calculation.

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 σ_N (absolute value) and the less the E_LUMO value, the greater was the inhibition efficiency.

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.

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.

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.

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.

The traditional management skills of planning, organizing, directing and controlling are inadequate in the fast‐paced, constantly changing, highly complex world of twenty‐first century organizations. This article uses concepts from quantum mechanics and chaos theory as metaphors for a new management skill set that can enable managers to actualize more of their leadership potential. The seven quantum skills are ancient and futuristic, scientific and spiritual, simple and complex. Together they form a model that balances the traditional left‐brain management skills with new skills that more fully utilize both hemispheres of the brain. As managers master these skills, they transcend the limitations of mechanistic, deterministic, reductionistic thinking and become authentic change masters, changing themselves and their organizations at depth.

The British Prime Minister's Office has recently opened a Web site. Although it does contain selected Prime Minister's speeches, transcripts and interviews, Prime Ministers' biographies (back to Harold Macmillan at present), and a tour of Number 10, it is also an entry point to British executive department government sites. The Cabinet Ministers' Biography section contains information on 23 ministers and links to Cabinet Web sites. There is also a page of government department pointers.

The law-oriented short stories and novels of lawyer/English professor John William Corrington are receiving increasing attention from legal scholars. However, no one has analyzed the science fiction screenplays he co-wrote with his wife, Joyce, from a legal perspective. This article analyzes two such screenplays and concludes that they are “Socratic” texts whose narrative structures and epistemological processes work in much the same way that the traditional participatory exchange works in law school. My analysis explores the links between law, allegory and science fiction as intersecting methods to imagine the possibilities for the future.

This study aims to prevent mild steel (MS) against corrosion in 0.5 M HCl solution, 2-amino-4-methoxy-6-methyl-1,3,5-triazine was used. The effectiveness of the compound as a corrosion inhibitor was studied via electrochemical, surface and theoretical calculation techniques.

For concentrations ranging from 0.5 to 10.0 mM, almost similar polarization resistances were obtained from electrochemical impedance spectroscopy (EIS) and linear polarization resistance tests. It also investigated inhibitive activity of 2-amino-4-methoxy-6-methyl-1,3,5-triazine on the steel surface using scanning electron and atomic force microscope instruments. Langmuir adsorption is the best matched isotherm for the adsorption of the inhibitor to the steel surface.

EIS method was used to determine inhibition efficiency, which was determined to be 95.7% for 10.0 mM inhibitor containing acid solution. Density functional theory’s predictions for quantum chemistry agreed well with the other experimental results.

The methods used in this study are effective and applicable; the used organic inhibitor is 2-amino-4-methoxy-6-methyl-1,3,5-triazine; and protective effectiveness is important, which is crucial for the task of MS corrosion prevention.

Nanosensors have a wide range of applications because of their high sensitivity, selectivity and specificity. In the past decade, extensive and pervasive research related to nanosensors has led to significant progress in diverse fields, such as biomedicine, environmental monitoring and industrial process control. This led to better and more efficient detection and monitoring of physical and chemical properties at better resolution, opening new horizons in the development of novel technologies and applications for improved human health, environment protection, enhanced industrial processes, etc.

In this paper, the authors discuss the application of citation network analysis in the field of nanosensor research and development. Cluster analysis was carried out using papers published in the field of nanomaterial-based sensor research, and an in-depth analysis was carried out to identify significant clusters. The purpose of this study is to provide researchers to identify a pathway to the emerging areas in the field of nanosensor research. The authors have illustrated the knowledge base, knowledge domain and knowledge progression of nanosensor research using the citation analysis based on 3,636 Science Citation Index papers published during the period 2011 to 2021.

Among these papers, the bibliographic study identified 809 significant research publications, 11 clusters, 556 research sector keywords, 1,296 main authors, 139 referenced authors, 63 nations, 206 organizations and 42 journals. The authors have identified single quantum dot (QD)-based nanosensor for biological applications, carbon dot-based nanosensors, self-powered triboelectric nanogenerator-based nanosensor and genetically encoded nanosensor as the significant research hotspots that came to the fore in recent years. The future trend in nanosensor research might focus on the development of efficient and cost-effective designs for the detection of numerous environmental pollutants and biological molecules using mesostructured materials and QDs. It is also possible to optimize the detection methods using theoretical models, and generalized gradient approximation has great scope in sensor development.

The future trend in nanosensor research might focus on the development of efficient and cost-effective designs for the detection of numerous environmental pollutants and biological molecules using mesostructured materials and QDs. It is also possible to optimize the detection methods using theoretical models, and generalized gradient approximation has great scope in sensor development.

This is a novel bibliometric analysis in the area of “nanomaterial based sensor,” which is carried out in CiteSpace software.

Study of corrosion behaviour could benefit from quantum chemical calculation to investigate the role of adsorption of main anions such as OH⁻ and Cl⁻ on metallic surfaces. The purpose of this study is to report the quantum chemical study of aluminium immersed in NaOH, NaCl and HCl solutions and verifying the calculations by potentiodynamic and open-circuit potential (OCP) measurements.

The electrochemical evaluations based on potentiodynamic polarization and OCP experiments were carried out. For theoretical investigations, the quantum chemical calculation was performed. In this regard, the adsorption of Cl⁻, OH⁻ and H⁺ on aluminium surface was investigated. Furthermore, the natural bond orbital for the direction and magnitude of charge transfer interactions was calculated.

The calculations indicate that higher interaction energy between ions with the metallic cluster being modelled together with natural bond orbital calculations of direction and magnitude of charge transfer accurately predicts corrosion.

This paper shows that ions such as Cl⁻, OH⁻ and H⁺ cause the corrosion of aluminium in NaOH, NaCl and HCl environments. The overall theoretical data corroborate with experimental results.

The purpose of this study is to perform quantum chemical calculations based on the DFT method on four bipyrazoles used as corrosion inhibitors for the plain carbon (“mild”) steel in acid media to determine the relationship between inhibition efficiency and the molecular structure of inhibitors.

Several quantum chemical parameters, such as the charge distribution, energy and distribution of highest occupied molecular orbital and lowest unoccupied molecular orbital, the absolute electronegativity (χ) values and the fraction of electrons (△N) transferring from inhibitors to the steel surface, were calculated and correlated with inhibition efficiencies.

The results showed that the inhibition efficiency of bipyrazole increased with the increasing in EHOMO, and the areas containing N atoms were the most probable sites to donate electrons for adsorbing the inhibitor molecules onto the metal surface.

It is a useful method to investigate the mechanisms of reaction by calculating the structure and electronic parameters, which can be obtained by means of theoretical quantum theory. Thus, the behavior and mechanism of the organic inhibitors can be obtained. Quantum chemical method can also be used to guide the selection and molecular design of inhibitors.