Search results

Nanotechnology (NT) advancements in personal protective textiles (PPT) or personal protective equipment (PPE) have alleviated spread and transmission of this highly contagious viral disease, and enabled enhancement of PPE, thereby fortifying antiviral behavior.

Review of a series of state of the art research papers on the subject matter.

This paper expounds on novel nanotechnological advancements in polymeric textile composites, emerging applications and fight against COVID-19 pandemic.

As a panacea to “public droplet prevention,” textiles have proven to be potentially effective as environmental droplet barriers (EDBs).

PPT in form of healthcare materials including surgical face masks (SFMs), gloves, goggles, respirators, gowns, uniforms, scrub-suits and other apparels play critical role in hindering the spreading of COVID-19 and other “oral-respiratory droplet contamination” both within and outside hospitals.

When used as double-layers, textiles display effectiveness as SFMs or surgical-fabrics, which reduces droplet transmission to <10 cm, within circumference of ∼0.3%.

NT advancements in textiles through nanoparticles, and sensor integration within textile materials have enhanced versatile sensory capabilities, robotics, flame retardancy, self-cleaning, electrical conductivity, flexibility and comfort, thereby availing it for health, medical, sporting, advanced engineering, pharmaceuticals, aerospace, military, automobile, food and agricultural applications, and more. Therefore, this paper expounds on recently emerging trends in nanotechnological influence in textiles for engineering and fight against COVID-19 pandemic.

Nowadays fossil fuel prices have increased; therefore, consumption of energy reduction has become a significant issue. Hence, this study aims to explore energy-efficient mechanical devices and their energy management.

This study focused on numerical analysis of various factors, including pressure drop, sensitivity, heat transfer and friction factor. This study compared the performance of two different arrangements of the heat exchanger: flat tube and staggered circular tube. This study also investigated the impact of varying coolant volume fractions.

This numerical analysis compares the geometric properties of flat and circular tube cross-sections while considering the flow of nanofluid inside and air outside. The current experimental investigation specifically examines the temperature-dependent characteristics (specific heat capacity, viscosity, density and thermal conductivity) of the stable ternary hybrid nanofluid mixture composed of Al₂O₃, CuO and TiO₂.

While several researchers have conducted numerical investigations on laminar flow in circular tubes, only a few studies are available on flat tube heat exchangers that use nanofluids just for internal flow. Furthermore, there is no simultaneous study on internal and exterior flow. Therefore, more investigation is necessary to examine the combined three-dimensional examination of shapes and their thermal-hydraulic influence using hybrid nanofluids.

This paper aims to try to develop new, environmentally friendly and efficient lubricating additives; study the compatibility of carbon-based additives with different base oils [Polyalphaolefin (PAO)-3, PAO-20 and NPE-2]; and explore the lubrication mechanism.

Oleylamine modified carbon nanoparticles (CNPs-OA) were prepared and the dispersion stability of CNPs-OA in PAO-3, PAO-20 and NPE-2 base oils was investigated by transmission electron microscopy, Fourier transform infrared, thermogravimetric analysis, energy dispersive spectroscopy and X-ray photoelectron spectroscopy. Universal Mechanical Tester (UMT) platform was used to carry out experiments on the effects of different additive concentrations on the lubricating properties of base oil.

The mean friction coefficient of PAO-3, PAO-20 and NPE-2 reduced by 32.8%, 10.1% and 11.4% when the adding concentration of CNPs-OA was 1.5, 2.0 and 0.5 Wt.%, respectively. Generally, The CNPs-OA exhibited the best friction-reducing and anti-wear performance in PAO-3.

The agglomeration phenomenon of carbon nanoparticles as lubricating additive was improved by surface modification, and the lubricating effect of carbon nanoparticles in three synthetic aviation lubricating base oils was compared.

This study aims to address these challenges by enhancing the resistance of Ag-based pastes to corrosion and sulfurization, thereby improving their performance and weatherability in high-power and high-frequency electronic applications.

This study investigates the influence of Sn doping in W-doped Ag paste to enhance resistance against electrochemical corrosion and sulfurization. A systematic examination was conducted using transient liquid phase sintering and solid–liquid inter-diffusion techniques to understand the microstructural and electrochemical properties.

This study found that Sn addition in W-doped Ag paste significantly improves its resistance to electrochemical corrosion and sulfurization. The sintering process at 600°C led to the formation of an Ag₂WO₄ phase at the grain boundaries, which, along with the presence of Sn, effectively inhibited the growth of Ag₂WO₄ grains. The 0.5% Sn-doped samples exhibited optimal anti-corrosion properties, demonstrating a longer grain boundary length and a passivation effect that significantly reduced the corrosion rate. No Ag₂S phase was detected in the weatherability tests, confirming the enhanced durability of the doped samples.

The findings of this study highlight the potential of Sn-doped Ag-W composites as a promising material for electronic components, particularly in environments prone to sulfurization and corrosion. By improving the anti-corrosion properties and reducing the grain size, this study offers a new approach to extending the lifespan and reliability of electronic devices, making a significant contribution to the development of advanced materials for high-power and high-frequency applications.

Hexavalent chromium has been a benchmark corrosion inhibitor before it was phased out because of its carcinogenic properties. However, because it was phased out, many alternative corrosion inhibitors have been introduced but failed to meet the performance of this benchmark inhibitor. Consequently, benzotriazole (BTA) was reported to exhibit chromate-like inhibition performance. Subsequently, Intelli-ion was reported by researchers to exhibit chromate-like performance also with claims of being a unique alternative. This paper aims to review the inhibition performance of these two alternatives. Above all, promotes the unique inhibition performance of Intelli-ion that makes it suitable for application in many sectors.

In this paper, the corrosion inhibition performances of BTA and Intelli-ion were compared systematically by reviewing some related literatures based on the opinion of the authors.

Different methodologies for measuring the inhibition performance of BTA showed that it’s an inhibitor of choice. However, the cut edge corrosion performance of Intelli-ion and BTA corrosion inhibitors on galvanized steel of 55% Wt.% Al, 44% Wt.% Zn and 1% Wt.% Si in 5 Wt.% NaCl solution was compared when subjected to scanning vibrating electrode technique (SVET) for 24 h. The results showed faint blue-colored region depicting negative cathodic current density for the Intelli-ion while there was a high-intensity of red-colored region depicting a positive anodic current density for BTA. In other words, the Intelli-ion inhibitor had a better overall cut-edge corrosion inhibition performance than the BTA inhibitor.

This paper compares and further, summarizes the corrosion inhibition performance of Intelli-ion and BTA by evaluating SVET results from the literature. In addition, it serves as an overview and reference for the unique inhibition performance of Intelli-ion when applied in field applications.

The purpose of this study is to analyze the free convection phenomena arising from a temperature disparity between a cold circular cylinder and a heated corrugated cylinder.

Numerical simulations were used to analyze the convection patterns. The inner cylinder, made of a thermally conductive solid material, was heated through its inner surface, while the space between the cylinders was filled with air. The governing equations for velocity, pressure and temperature were solved using a Galerkin finite element method-based solver for partial differential equations.

The study explored various parameters affecting the dynamic and thermal structure of the flow, including the Rayleigh number (10³ ≤ Ra ≤ 10⁶), the number of corrugations of the inner cylinder (3 ≤ N ≤ 18), the thermal conductivity of the hollow cylinder (1 ≤ K ≤ 200) and the angle of inclination of the inner cylinder (0° ≤ φ ≤ 90°). Results indicated a notable sensitivity of flow intensity to changes in the Rayleigh number and the inner cylinder’s inclination angle φ. Particularly, for Ra = 10⁶, the average heat transfer rate increased by 203% with a K ratio increment from 1 to 100 but decreased by 16.3% as the number of corrugations increased from 3 to 18.

This research contributes to understanding the complex interplay between geometry, thermal properties and flow dynamics in natural convection systems involving cylindrical geometries. The findings offer useful insights for improving the transfer of heat procedures in real-world situations.

This study aims to investigate the machining performance of CVD-coated carbide tools by considering most crucial machinability aspects: cutting force, tool life, surface roughness and chip morphology in high-speed hard turning of AISI 4340 alloy steel under a sustainable minimum quantity lubrication (MQL) environment.

The purpose of this study is to analyze the performance of coated carbide tools under MQL environment therefore, machining tests were performed in accordance with the Taguchi L9 orthogonal array, accommodating the three crucial machining parameters such as cutting speed (V = 300–400 m/min), feed rate (F = 0.1–0.2 mm/rev) and depth of cut (DOC = 0.2–0.4 mm). The measured or calculated values obtained in each experimental run were validated for normality assumptions before drawing any statistical inferences. Taguchi signal-to-noise (S/N) ratio and analysis of variance methodologies were used to examine the effect of machining variables on the performance outcomes.

The quantitative analysis revealed that the depth of cut exerted the most significant influence on cutting force, with a contributing rate of 60.72%. Cutting speed was identified as the primary variable affecting the tool life, exhibiting a 47.58% contribution, while feed rate had the most dominating impact on surface roughness, with an overall contributing rate of 89.95%. The lowest cutting force (184.55 N) and the longest tool life (7.10 min) were achieved with low machining parameters at V = 300 m/min, F = 0.1 mm/rev, DOC = 0.2 mm. Conversely, the lowest surface roughness (496 nm) was achieved with high cutting speed, low feed rate and moderate depth of cut at V = 400 m/min, F = 0.1 mm/rev and DOC = 0.3 mm. Moreover, the microscopic examination of the chips revealed a serrated shape formation under all machining conditions. However, the degree of serration increased with an incremental raise with cutting speed and feed rate.

The study is limited to study the effect of machining parameters within the stated range of cutting speed, feed rate and depth of cut as well as other parameters.

Practitioners may consider to adopt this machining technique to create more sustainable working environment as well as eliminate the disposal cost of the used metal cutting fluid.

By applying this machining technique, diseases caused by metal cutting fluid to the mechanist will be significantly reduced, therefore creating better lifestyles.

Hard turning is commonly carried out with advanced cutting tools such as ceramics, cubic boron nitride and polycrystalline cubic boron nitride to attain exceptional surface finish. However, the high cost of these tools necessitates exploration of alternative approaches. Therefore, this study investigates the potential of using cost-effective, multilayer-coated carbide tools under MQL conditions to achieve comparable surface quality.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2024-0013/

This paper aims to prepare high corrosion-resistant chromium-free zinc-aluminum (Zn–Al) coatings reinforced with multi-walled carbon nanotubes (MWCNTs) and nano-ZnO particle composites.

The morphology, composition and corrosion resistance of the coatings were analyzed by electrochemical tests, water contact angle tests, immersion tests, scanning electron microscopy/energy dispersive spectrometer and X-ray diffraction.

The composite coating with 0.3% MWCNTs and 0.5% nano-ZnO particles demonstrated both high shielding performance and cathodic protection performance, which was attributed to the porosity filling of MWCNTs and nano-ZnO particles together with the electrical connection of MWCNTs between the zinc and aluminum powders.

This work laid an experimental foundation for the preparation and corrosion mechanism of high corrosion-resistant chromium-free Zn–Al coating reinforced with MWCNTs and nano-ZnO particles.

The purpose of this study is to investigate the simultaneous effects of normal wall transpiration, stretching strength parameter, velocity slip and nanoparticles on the flow of a ternary hybrid nanofluid through an elastic surface. The goal is to understand the behavior of the flow field, temperature distribution, skin friction and temperature gradient under these conditions, and to explore the existence and nature of solutions under varying parameter values.

The analysis involves expressing the flow field, power-law temperature field, skin friction and temperature gradient in closed-form formulas. The study examines both stretching and shrinking surfaces, distinguishing between unique and dual solutions. The methodology includes deriving exact solutions for exponential and algebraic temperature and temperature rate formulas analytically by deriving the system of governing equations into ordinary differential equations.

The study reveals that for a stretching sheet, the solution is unique, whereas dual solutions are observed for a shrinking surface. Special solutions are provided for various parametric values, showing the behavior of the exponential and algebraic temperature and temperature rate, with a focus on identifying turning points that demarcate the existence and non-existence of single or multiple solutions. The solutions are represented through graphs and tables to facilitate a comprehensive qualitative analysis. The research identifies turning points that determine the presence or absence of single or multiple solutions, uncovering multiple solutions for different parameter sets. These findings are displayed graphically and in tabular form, highlighting the complex interplay between the parameters and the resulting flow behavior.

This analysis contributes to the field by providing new insights into the multiple solution phenomena in ternary hybrid nanofluid flows, particularly under the combined effects of normal wall transpiration, stretching strength, velocity slip and nanoparticle presence. The identification of turning points and the exact solutions for various temperature profiles are of significant value, offering a deeper understanding of the factors influencing the flow and thermal characteristics in such systems. The study’s findings have potential applications in optimizing fluid flow in engineering systems where such conditions are prevalent.

In the present article, sensitivity analysis was studied in the presence of the combined effects of thermal radiation, suction and magnetohydrodynamics (MHD) effects on a Nimonic 80A-Fe_3O4/water hybrid nanofluid across moving a wedge with variable surface temperature and buoyancy effects.

The governing equations were transformed using similarity transformations and solved using MATLAB bvp4c code and response surface methodology (RSM), with quadratic face-centred central composite design being implemented. All results and graphs were formulated after positive outcomes of our results with existing literature.

An increase in magnetic parameter (M) and velocity ratio parameter (R) resulted in an increase in velocity profiles and local Nusselt number, while a reverse trend was observed for temperature profiles. With radiation parameter Rd = 0.8, the local Nusselt number increased by 4.08% as the velocity ratio parameter increased from R = 0.0 to R = 0.5. The Nusselt number was found to be most sensitive to R, while the latter produced negative sensitivity on skin friction coefficient. The skin friction coefficient for the hybrid nanofluid model increased by 35.39% compared to the regular fluid model, with a very low standard deviation value of 10⁻⁴. The Model F-value for Nusselt number model was found to be 939278.49 with a noise ratio of 3618.711. Skin friction coefficient was found to be most sensitive with respect to changes in the parametric values of M.

Nimonic 80A being a super-alloy of nickel-iron-chromium and built in high frequency melting, it can work up to 1500°F and is extensively used in automobile exhaust valves.

The present study finds numerous applications in biotoxicity studies, medical industries, water heaters and the forging of hot exhaust valve heads.

In view of various applications of our present study, there remains a gap in examining the sensitivity analysis of a hybrid nanofluid flow model across a moving permeable wedge using the Tiwari–Das model, which required clinical investigations numerically and statistically.