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Article
Publication date: 22 May 2007

Alexander Bolonkin

This paper aims to suggest and research a revolutionary method‐transfer of electricity in outer Space with distance of hundreds of millions kilometers by ultra‐cool plasma cables.

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Abstract

Purpose

This paper aims to suggest and research a revolutionary method‐transfer of electricity in outer Space with distance of hundreds of millions kilometers by ultra‐cool plasma cables.

Design/methodology/approach

Methods of the plasma and electricity physic are used for research.

Findings

Theory of plasma cable transferring is offered, developed and its possibilities researched.

Research limitations/implications

This method uses a high voltage electricity and plasma source (accelerator).

Practical implications

Offers conclusions from the research of a revolutionary new idea‐transferring electric energy in the hard vacuum of outer space wirelessly, using a plasma power cord as an electric cable (wire). He computed the macroprojects: transference of hundreds kilowatts of energy to Earth's Space Station, transferring energy to the Moon or back, transferring energy to a spaceship at distance 100 million of kilometers, the transfer energy to Mars when one is located at opposite side of the distant Sun, transfer colossal energy from one of Earth's continents to another continent (for example, between Europe – USA) wirelessly – using Earth's ionosphere as cable, using Earth as gigantic storage of electric energy, using the plasma ring as huge MagSail for moving of spaceships.

Originality/value

The paper provides information on a revolutionary method for the transfer of electricity in outer space.

Details

Aircraft Engineering and Aerospace Technology, vol. 79 no. 3
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 12 January 2010

Ningbo Liao and Ping Yang

The small dimensions of future device designs also imply a stronger effect of material boundary resistance. For nanoscale devices and structures, especially, interface phenomena…

Abstract

Purpose

The small dimensions of future device designs also imply a stronger effect of material boundary resistance. For nanoscale devices and structures, especially, interface phenomena often dominate their overall thermal behavior. The purpose of this paper is to propose molecular dynamics (MD) simulations to investigate the mechanical and thermal properties at Cu‐Al interface.

Design/methodology/approach

The two‐temperature model (TTM)‐MD model is used to describe the electron‐phonon scattering at interface of different metals. Before the simulation of heat transfer process, a non‐ideal Cu‐Al interface is constructed by simulating diffusion bonding.

Findings

According to the simulation results, in unsteady state, the temperature distribution and the displacements of atoms near the interface tend to generate stress and voids. It reveals the damage mechanics at the interface in heat transfer.

Originality/value

The atomic model proposed in this paper is computationally efficient for interfacial heat transfer problems, and could be used for investigation of other interfacial behaviors of dissimilar materials.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 20 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 April 1991

Ming‐Cheng Cheng and E.E. Kunhardt

A non‐equilibrium multi‐valley transport model for carriers in compound semiconductor devices has been developed. This macroscopic transport model provides an efficient scheme for…

Abstract

A non‐equilibrium multi‐valley transport model for carriers in compound semiconductor devices has been developed. This macroscopic transport model provides an efficient scheme for device modeling, and can overcome the difficulty in evaluating the relaxation times in multi‐valley conservation equations without a priori assumption of the displaced‐Maxwellian distribution. This model has been successfully applied to electron transport in GaAs subjected to rapidly time‐varying fields. The results have suggested that the macroscopic effective mass of electrons might be strongly dependent on average velocity.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 10 no. 4
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 1 April 1993

Ming‐C. Cheng and Rambabu Chennupati

The concept of the evolution of the distribution function is used to derive an energy‐scale distribution that is able to describe transport phenomena, including inter‐valley…

Abstract

The concept of the evolution of the distribution function is used to derive an energy‐scale distribution that is able to describe transport phenomena, including inter‐valley transfer effect, in the scale as small as the energy relaxation time. The energy‐scale distribution is used to study the evolution of electrons in n‐type GaAs under the influence of rapid change in field. Results indicate that, near the peak of strong velocity overshoot or the bottom of pronounced undershoot in the Γ valley caused by the rapid change in field, the energy‐scale distribution can not respond as fast as the distribution function calculated from the Monte Carlo method. The average velocity resulting from the energy‐scale distribution therefore leads to less pronounced overshoot and undershoot than those obtained from the Monte Carlo method. However, since velocity overshoot and undershoot are not pronounced in the L‐valleys, the L‐valley energy‐scale distribution is in excellent agreement with that determined by the Monte carlo simulation.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 12 no. 4
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 3 January 2017

Mohammed Elalaoui Belghiti, Ayssar Nahlé, Abdeslam Ansari, Yasser Karzazi, S. Tighadouini, Yassir El Ouadi, A. Dafali, Belkheir Hammouti and Smaail Radi

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 3 May 2016

Hong Ju, Jiejing Chen, Can Sun and Yan Li

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…

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 April 1992

Ming‐C. Cheng

Influence of forward scattering, including ionized‐impurity and polar optical‐phonon scattering, on electron transport phenomena in a 3‐valley n‐type GaAs model subjected to a…

Abstract

Influence of forward scattering, including ionized‐impurity and polar optical‐phonon scattering, on electron transport phenomena in a 3‐valley n‐type GaAs model subjected to a rapid change in field is studied. It is shown that the macroscopic effective mass of electrons in a nonparabolic band structure is smaller than the energy‐dependent effective mass, which is usually assumed for modeling of GaAs devices, during the interval of velocity overshoot when strong forward scattering is involved. As a consequence, the hydrodynamic transport model, where the macroscopic effective mass is assumed energy dependent, leads to a smaller overshoot velocity.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 11 no. 4
Type: Research Article
ISSN: 0332-1649

Article
Publication date: 3 July 2017

Behnam Seyyedi

The purpose of this paper is to introduce bio-inspired FeN4-S-C black nano-electrocatalyst for the oxygen reduction reaction (ORR) in an alkaline medium. The FeN4-S-C derived…

Abstract

Purpose

The purpose of this paper is to introduce bio-inspired FeN4-S-C black nano-electrocatalyst for the oxygen reduction reaction (ORR) in an alkaline medium. The FeN4-S-C derived without pyrolysis of precursors in high temperature is recognized as a new electrocatalyst for the ORR in an alkaline electrolyte. For the proper design of bio-inspired nano-electrocatalyst for the ORR performance, chlorinated iron (II) phthalocyanine nanoparticles were used as templates for achieving the active sites in aqueous KOH by rotating disk electrode methods. The most active FeN4-S-C catalyst exhibited a remarkable ORR activity in the alkaline medium. The objectives of this paper are to investigate the possibility of nanoscale particles size (˜5nm) of electrocatalyst, to achieve four-electron transfer mechanism and to exhibit much superior catalytic stability in measurements. This paper will shed light on bio-inspired FeN4-S-C materials for the ORR catalysis in alkaline fuel cells.

Design/methodology/approach

The paper presents a new bio-inspired nano-electrocatalyst for the ORR, which has activity nearby platinum/carbon electrocatalyst. Chlorinated iron phthalocyanine nanoparticles have been used as FeN4 template, which is the key point for the ORR. Bio-inspired nano-electrocatalyst has been fabricated using chlorinated iron phthalocyanine, sodium sulphide and carbon black.

Findings

The particles’ size was 5 nm and electron transfer number was 4.

Research limitations/implications

The catalyst that is used in this method should be weighed carefully. In addition, the solvent should be a saturated solution of NaCl in water.

Practical implications

The method provides a simple and practical solution to improving the synthesis of iron-based catalyst for ORR.

Originality/value

The method for the synthesis of bio-inspired electrocatalyst was novel and can find numerous applications in industries, especially as ORR non-precious metal catalyst.

Details

Pigment & Resin Technology, vol. 46 no. 4
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 20 December 2023

Halime Morovati, Mohammad Reza Noorbala, Mansoor Namazian, Hamid R. Zare and Ahmad Ali Dehghani-Firouzabadi

The main purpose of the present work is to introduce two new Schiff bases as corrosion inhibitors (CIs) for carbon steel (CS). The anti-corrosion performance of these Schiff bases…

Abstract

Purpose

The main purpose of the present work is to introduce two new Schiff bases as corrosion inhibitors (CIs) for carbon steel (CS). The anti-corrosion performance of these Schiff bases having N and S heteroatoms in their structures was investigated and compared in 2 M HCl electrolyte. The inhibitory activity of these Schiff bases was also assessed.

Design/methodology/approach

Common electrochemical assays like potentiodynamic polarization and electrochemical impedance measurements were used to evaluate the ability of compounds in reduction of the rate of corrosion. Quantum chemical calculations (QCCs) were also used to examine the corrosion inhibitive and the process related to the electrical and structural characteristics of the molecules acting as CIs.

Findings

The electrochemical measurements indicate that both Schiff bases acted as the efficient CIs of CS in 2 M HCl electrolyte. The adsorption of the Schiff base on the surface of the CS caused the corrosion to be inhibited. The change of Gibbs energies indicated that both physical and chemical interactions are involved in the adsorption of NNS and SNS on CS surfaces. The predicted QCCs of the CIs neutral and positively charged versions were well-aligned with those obtained by electrochemical experiments.

Originality/value

Using electrochemical experiments and quantum chemical modelings, two new Schiff bases, N-2-((2-nitrophenyl)thio)phenyl)-1-(pyrrole-2-yl)methanimine (NNS) and N-2-((2-nitrophenyl)thio)phenyl)-1-(thiophen-2-yl)methanimine (SNS), were evaluated as anti-corrosion agents for CS in 2 M HCl electrolyte. The DFT calculations were considered to compute the quantum chemical parameters of the inhibitors.

Details

Anti-Corrosion Methods and Materials, vol. 71 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 2 September 2019

Aziz Boutouil, My Rachid Laamari, Ilham Elazhary, Hafid Anane, Abdeslem Ben Tama and Salah-Eddine Stiriba

This study aims to investigate the inhibition effect of a newly synthesized1,2,3-triazole containing a carbohydrate and imidazole substituents, namely…

110

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

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