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The purpose of this paper is to investigate the three fundamental flows (namely, both the plates moving in opposite directions, the lower plate is moving and other is at rest, and both the plates moving in the direction of flow) of the Ree-Eyring fluid between infinitely parallel plates with the effects of magnetic field, porous medium, heat transfer, radiation and slip boundary conditions. Moreover, the intention of the study is to examine the effect of different physical parameters on the fluid flow.

The mathematical modeling is performed on the basis of law of conservation of mass, momentum and energy equation. The modeling of the present problem is considered in Cartesian coordinate system. The governing equations are non-dimensionalized using appropriate dimensionless quantities in all the mentioned cases. The closed-form solutions are presented for the velocity and temperature profiles.

The graphical results are presented for the velocity and temperature distributions with the pertinent parameters of interest. It is observed from the present results that the velocity is a decreasing function of Hartmann number. Temperature increases with the increase of Ree-Eyring fluid parameter, radiation parameter and temperature slip parameter.

First time in the literature, the authors obtained closed-form solutions for the fundamental flows of Ree-Erying fluid between infinitely parallel plates with the effects of magnetic field, porous medium, heat transfer, radiation and slip boundary conditions. Moreover, the results of this paper are new and original.

The purpose of this study is to develop a protective coating system on mild steel panel incorporating epoxidized natural rubber with acrylic polyol resin.

In this work, a novel attempt is made to develop binder coatings using epoxidized natural rubber-based material and an organic resin (acrylic resin) for corrosion protection on metal substrate. Seven different samples of multifunctional coatings are developed by varying the compositions of epoxidized natural rubber (ENR) and acrylic resin. The properties of the developed coatings have been characterized using analytical methods such as Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). EIS has been carried out for 30 days to evaluate the corrosion resistance after immersing into 3.5 wt.% of sodium chloride. Cross hatch cut tester (CHT) has been used to study the adhesive properties. UV–Visible Spectroscopy (UV–Vis) was also used to assess changes in the coating-film transparency of the natural rubber-based coating systems in this study.

The developed coatings have formed uniform layer on the substrate. CHT results show excellent adhesion of the coatings. Higher concentrations of ENR have higher transparency level, which reduces when the acrylic concentration increases. FTIR analysis confirms the crosslinking that occurred between the components of the coatings. Based on the impedance data from EIS, the incorporation of natural rubber can be an additive for the corrosion protection, which has the coating resistance values well above 108Ω even after 30 days of immersion.

The blending method provides a simple and practical solution to improve the strength and adhesion properties of acrylic polyol resin with epoxidized natural rubber. There is still improvement needed for long-term applications.

The work has been conducted in our laboratory. The combination of natural rubber-based materials and organic resins is a new approach in coating research.

The purpose of this paper is to study the electrochemical, mechanical and thermal characteristics of polyester – epoxy coating systems using electrochemical impedance spectroscopy (EIS), pull-off test and differential scanning calorimetry (DSC). These are very important properties to evaluate the performance of a coating system. Proper measurement and analysis techniques are needed for a proper evaluation of these properties to ensure the coating performance.

Different ratios of polyester and epoxy resins have been blended to formulate good anticorrosive, mechanically strong and thermally stable binder coating system. EIS, pull-off test and DSC were used to evaluate these properties.

The sample containing 90 wt.% polyester exhibited the best corrosion resistance from the beginning until the end of exposure time. The value of corrosion resistance (R_c) obtained on the 30th day of exposure was found to be 2.89 × 108 ohm cm⁻². The glass transition temperature (T_g) was found to be increasing with the incorporation of epoxy to the binder system. The result from pull-off test showed the best adhesion with the sample containing 90 wt.% polyester which also has the lowest T_g promoted better adhesion properties.

The curing time must be reduced for practical applications.

Hybrid coatings systems have been formulated. This paper discusses on the highest coating resistance obtained polymer-substrate mechanical properties and thermal characteristic of the polyester/epoxy binder resin using DSC.

Electronic devices aid communication during new communication phases and the scope of cognitive radio networks has changed communication paradigms through efficient use of spectrums. The communication prototype of cognitive radio networks defines user roles as primary user and secondary user in the context of the spectrum allocation and use. The users who have licensed authority of the spectrum are denoted as primary users, while other eligible users who access the corresponding spectrum are secondary users.

The multiple factors of transmission service quality can have a negative influence due to improper scheduling of spectrum bands between primary users and secondary users. There are considerable contributions in contemporary literature concerning spectrum band scheduling under spectrum sensing. However, the majority of the scheduling models are intended to manage a limited number of transmission service quality factors. Moreover, these service quality factors are functional and derived algorithmically from the current corresponding spectrum. However, there is evidence of credible performance deficiency regarding contemporary spectrum sensing methods

This article intends to portray a fuzzy guided integrated factors-based spectrum band sharing within the spectrum used by secondary users. This study attempts to explain the significance of this proposal compared to other contemporary models.

This article intends to portray a fuzzy guided integrated factors-based spectrum band sharing within the spectrum used by secondary users. This study attempts to explain the significance of this proposal compared to other contemporary models.

Corrosion is an important problem to be taken care in terms of economic and ecological aspects. The aim of this paper is to identify the methods of protection and selection of materials for corrosion protection.

A novel attempt has been made to formulate a hybrid composite paint system using silicone (S2) and polyester (P3) resins. These resins have been blended in different weight ratios to develop binder for protection coatings. Cross‐hatch test, impact resistance test, thermal characterization, impedance measurement and potential‐time measurement were conducted on binder coated steel panels. Heat resistance test was carried out using ASTM D2485 standards.

The results showed that physical and mechanical properties of the coatings have been improved by the addition of silicone into the polyester matrix. The binder system developed using 50 wt per cent polyester and 50 wt per cent silicone showed good physical, mechanical properties and high thermal resistance. The maximum coating resistance of the coatings after 30 days exposure was found to be 9.7×10⁶ Ω and the coating can withstand high temperature up to 473 K.

The development of different types of coatings will be useful to achieve higher protection performance. The combinations of different resins and pigments have to be analysed and selected suitable compositions.

The objective of this study is to develop coating system with different resins to achieve better performance and reduce the cost of paint materials. It may be useful for the industries to move forward with new formulation using multicomponent coating materials. A critical combination of the above resins offers better protection for steel structures from high temperature corrosive environments.

The formulation of coating material using two different resins and a single curing agent is a novel approach in this research. This type of research will open new ideas of formulating different coatings using various types of resins. In high temperature corrosion environment, the coatings which is commonly used is silicone based and the price of the raw material is very high therefore to reduce the cost of the raw material, the silicone resin is being blended in different ratios with organic resin to obtain an optimum ratio which can be applied to overcome high temperature corrosion on steel panels.

This study aims to fabricate the acrylic-based polymeric composite coating with a hydrophobic surface associated with natural oil polyol (NOP) and polydimethylsiloxane with the incorporation of 3 Wt.% SiO₂ nanoparticle (SiO₂np) against the corrosive NaCl media.

The structural properties of the formulated polymeric composite coatings were investigated by using Fourier transform infrared spectroscopy, ultraviolet-visible spectroscopy, water contact angle (WCA) and cross-hatch (X-Hatch) tests. The WCA measurement was used to study the surface wettability of the formulated polymeric composite coatings. The corrosion protection performance of the nanocomposite coated on the mild steel substrate was studied by immersing the samples in 3.5 Wt.% NaCl solution for 30 days using electrochemical impedance spectroscopy.

The enhanced polymeric composite coating system performed with an excellent increase in the WCA up to 111.1° which is good hydrophobic nature and very high coating resistance in the range of 10¹⁰ Ω attributed to the superiority of SiO₂np.

The incorporation of SiO₂np into the polymeric coating could enhance the surface roughness and hydrophobic properties that could increase corrosion protection. This approach is a novel attempt of using NOP along with the addition of SiO₂np.

The purpose of this study is to develop anti-corrosion coating systems using disposable waste materials. The dissolved polyethylene terephthalate (PET) has been blended with epoxy resin and stoichiometrically cured with a polyamide resin.

Glycolysis process was found to be the most optimum candidate to dissolve PET. The developed coating systems were characterized by Fourier transform infrared spectroscopy for confirmation of the molecular bonding structures. The mechanical properties were characterized by performing pull-off test and cross hatch test for mechanical properties on the coated panel. Also, the glossiness test was used by reflecting light on the coated surface. The corrosion protection performance of the coated mild steel panels was examined using electrochemical impedance spectroscopy. Furthermore, the wettability of the developed coating systems was evaluated by using water contact angle technique.

It was observed that the coating system which contains 10 per cent of dissolved PET (S2) showed the highest adhesion and corrosion protection properties.

Recyclable PET bottles have outstanding chemical properties, adhesion properties, low cost, low permeability to gases and solvents making it suitable as a coating with superior barrier properties.

This study aims to propose that the corrosion resistance of the neat epoxy coating can be further enhanced by incorporating reinforcing agents.

Chitosan, silica and their hybrid compound were used to study the subject of corrosion resistance of epoxy coating systems. This work used 3.5 Wt.% NaCl solution as the electrolyte, and electrochemical impedance spectroscopy (EIS) was used to investigate the electrochemical behaviour of the studied coating systems. Standard and accelerated states were used without and with scratch on the coating layer.

It was found that the impedance value of composite coating incorporated with the hybrid compound was significantly higher at 10¹⁰ Ω after 14 days of exposure in both testing states. The breakpoint frequency (f_b) determination also proves with large capacitive region at low-to-high frequency of impedance plots corresponding to the high corrosion resistance.

The hybrid compound consisting of chitosan as organic biopolymer and silica as inorganic material, respectively, served as a promising reinforcing agent for composite coating as a promising corrosion inhibitor. Different states of EIS measurement were used which are standard (without scratch) and accelerated (with scratch) states associated with the f_b values.

The purpose of this paper is to develop the bio-composite organic coatings by adding the bio-based additives that are extracted from banana peels and henna leaves as the organic corrosion inhibitors.

Bioactive constituents with inhibition properties are extracted from banana peels and henna leaves by using ethanol to form the ethanolic extract. The inhibiting efficiency of these bioactive constituents on mild steel corrosion in 3.5% sodium hydroxide (NaCl) solution is investigated. The investigation is performed using electrochemical impedance studies for 30 days. The optical and adhesive properties of the bio-composite coating systems have also been studied.

The best protection is obtained as the loading ratio of the banana peels ethanolic extract (BPEE) and henna leaves ethanolic extract (HLEE) are 10 Wt.% and 30 Wt.%, respectively. Overall, the results obtained show that the BPEE and HLEE not only enhance the optical properties but also can serve as an effective inhibitor for corrosion without affecting the adhesiveness of the neat acrylic properties.

Banana peels and henna leaves consist of bioactive constituents that have anti-corrosion properties which could inhibit corrosion.

The purpose of this paper is to design novel tunnel field effect transistor (TFET) using graphene nanoribbons (GNRs).

To design the proposed TFET, the bilayer GNRs (BLGNRs) have been used as the channel material. The BLGNR-TFET is designed in QuantumATK, depending on 2-D Poisson’s equation and non-equilibrium Green’s function (NEGF) formalism.

The performance of the proposed BLGNR-TFET is investigated in terms of current and voltage (I-V) characteristics and transconductance. Moreover, the proposed device performance is compared with the monolayer GNR-TFET (MLGNR-TFET). From the simulation results, it is investigated that the BLGNR-TFET shows high current and gain over the MLGNR-TFET.

This paper presents a new technique to design GNR-based TFET for future low power very large-scale integration (VLSI) devices.