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[Display omitted] Rechargeable zinc-air batteries (ZABs) are viewed as a promising solution for electric vehicles due to their potential to provide a clean, cost-effective, and sustainable energy storage system for the next generation. Nevertheless, sluggish kinetics of the oxygen evolution reaction (OER), the oxygen reduction reaction (ORR) at the air electrode, and low power density are significant challenges that hinder the practical application of ZABs. The key to resolving the development of ZABs is developing an affordable, efficient, and stable catalyst with bifunctional catalytic. In this study, we present a series of bifunctional catalysts composed of Co/Zn nanoparticles uniformly embedded in nitrogen-doped carbon (NC) and multi-walled carbon nanotubes (MWCNTs) denoted as Co/Zn@NC@MWCNTs. The incorporation of MWCNTs using a facile and non-toxic method significantly decreased the overpotential of the OER from 570 to 430 mV at 10 mA cm−2 and the peak power density from 226 to 263 mW cm−2. Besides, the electrochemical surface area measurements and electrochemical impedance spectroscopy indicate that the three-dimensional (3D) network structure of MWCNTs facilitates mass transport for ORR and reduces electron transfer resistance during OER, leading to a small potential gap of 0.86 V between OER and ORR, high electron transfer number (3.92–3.98) of the ORR, and lowest Tafel slope (47.8 mV dec−1) of the OER in aqueous ZABs. In addition, in-situ Raman spectroscopy revealed a notable decrease in the I D /I G ratio for the optimally configured Co/Zn@NC@MWCNTs (75:25), indicating a reduction in defect density and improved structural ordering during the electrochemical process, which directly contributes to enhanced ORR activity. Hence, this study provides an excellent strategy for constructing a bifunctional catalyst material with a 3D MWCNTs conductive network for the development of advanced ZAB systems for sustainable energy applications. [ABSTRACT FROM AUTHOR]

This paper presents a pH sensor with a Mach–Zehnder Interferometer (MZI) that operates in solutions of 4.0, 7.0, and 10.0. The sensor device consists of two tapered sections with dimensions of 1 mm/1 mm/1 mm for down-taper, waist-length, and up-taper, respectively, with a separation of 10 mm. The diameter of the waist is 40  μ m. This work includes the experimental evaluation of an MZI fiber optic pH sensor at 1559 nm, where 1559 nm represents a specific wavelength chosen for its optimal sensitivity in evaluating the sensor pH detection performance. It is not the central wavelength of the optical fiber, but one of the minimal values selected to enhance the interaction between the evanescent field and the sample, ensuring the reliable detection of pH variations. These sensor dimensions and the functionalized solution of multi-walled carbon nanotubes (MWCNTs) increase the detection of pH in dyes used in the textile industry. Alizarin is a strong anionic red dye that is part of the anthraquinone dye group. The experimental results demonstrated effective detection of pH levels in water contamination involving dye. This development could resolve the problem with Alizarin. The simple fabrication, low cost, and stability of the optical response make this sensor relevant for pH measurements in water contamination. [ABSTRACT FROM AUTHOR]

Abstract This study investigates the thermal behaviour of unsteady hybrid nanofluid flow on an infinite vertical plate. The investigation takes into account parameters such as magnetohydrodynamics and radiation effects, as well as the stratified medium. The systems of equations were solved by employing the explicit finite difference approach of Dufort-Frankel method. The main motivation of the study is to compare the performance of water, magnetic oxide, and multi-wall carbon nanotubes as working fluids. Additionally, velocity, temperature, and concentration outlines are visualized through plots, elucidating the fluid behaviour. Tables are provided for the Skin friction, Nusselt number, and Sherwood number, offering comprehensive insights crucial for optimizing performance in engineering applications ranging from thermal management systems to renewable energy technologies. The main finding of this study indicates that the quantitative result reveals that the temperature outline escalates among increasing values of radiation. In contrast, the outlines of a velocity and concentration show a decrease as the values of magnetohydrodynamics increase. In addition, multi-walled carbon nanotubes consume a larger outcome on temperature. A statistical study displays that the thermal stream rate of magnetic oxide-multi-wall carbon nanotubes-water increases from 1.7615 percentages to 7.4415 percentages, respectively, when the volume fraction of nanoparticles rises from 0.01 to 0.05. Future research is important to understanding hybrid nanofluid flows and their applications in thermal engineering systems such as energy systems, nuclear reactors, biomedical applications, electronics cooling, solar thermal systems, chemical processing, and other heat transfer applications where improved thermal performance is crucial.

The study investigated the effects of incorporating multi-walled carbon nanotubes (MWCNTs) into glass fiber-reinforced polymer composites on their mechanical and tribological properties. Experimental results demonstrated significant enhancements across various parameters. Microhardness increased by 25.03%, attributed to improved interfacial bonding and load transfer facilitated by MWCNTs. Tensile strength and modulus improved by 10.58% and 28.2%, respectively, indicating reinforced load-bearing capacity. Flexural strength and modulus increased by 33.78% and 36.29%, respectively, due to enhanced interfacial bonding. Inter-laminar shear strength (ILSS) exhibited a notable increase of 20.79% with MWCNT incorporation. Ity mpact toughness improved by 19.41% in Izod and 32.32% in Charpy tests, attributed to MWCNTs’ energy-dissipating properties and enhanced interfacial bonding. Tribological tests showed decreased wear and friction coefficients, along with reduced debris formation and fiber breakage in SEM analysis, indicating improved bonding between the matrix and fibers. Furthermore, an artificial neural network (ANN) model accurately predicted the coefficient of friction, aligning well with experimental values, offering potential for predictive modeling in composite material analysis. Overall, the incorporation of MWCNTs significantly enhanced mechanical properties and wear resistance of the composite material. [ABSTRACT FROM AUTHOR]

Styrene butadiene rubber (SBR) composites reinforced by cryptocrystalline graphite (CG) and multi‐wall carbon nanotubes (MWCNTs) were prepared. The SBR composite with 50 phr CG content displays superior mechanical reinforcement achieving 20.7 MPa in tensile strength. However, the electrical conductivity enhancement is modest. After incorporating MWCNTs as a secondary filler, the electrical conductivity significantly improved. The results show that the electrical conductivity of the SBR composite reinforced with 10 phr of CG and an additional 5 phr of MWCNTs surpasses that achieved by using 50 phr of CG solely. This enhancement can be attributed to the inherent excellent electric conductivity and high aspect ratio of MWCNTs, with their presence also preventing the re‐agglomeration of CG. Furthermore, within 10–40 phr content of CG, the mechanical reinforcement of CG‐SBR composites is enhanced with the addition of MWCNTs, whereas a minor decline in tensile strength is noted when the concentration of CG above 40 phr. Overall, the SBR composite reinforced with a synergistic combination of CG and MWCNTs is achieved, demonstrating both exceptional mechanical and conductive properties. Highlights: Styrene butadiene rubber (SBR) composites with different cryptocrystalline graphite (CG) phr and additional multi‐wall carbon nanotubes (MWCNTs) were characterized.CG‐SBR displays good mechanical property but limited electrical conductivity.Proper ratio of CG/MWCNTs significantly enhances various properties.MWCNTs act as a "bridge" structure connecting isolated CG filler in SBR matrix.MWCNTs network effectively prevents the re‐agglomeration of CG nanosheets. [ABSTRACT FROM AUTHOR]

This study investigates the thermal behaviour of unsteady hybrid nanofluid flow on an infinite vertical plate. The investigation takes into account parameters such as magnetohydrodynamics and radiation effects, as well as the stratified medium. The systems of equations were solved by employing the explicit finite difference approach of Dufort-Frankel method. The main motivation of the study is to compare the performance of water, magnetic oxide, and multi-wall carbon nanotubes as working fluids. Additionally, velocity, temperature, and concentration outlines are visualized through plots, elucidating the fluid behaviour. Tables are provided for the Skin friction, Nusselt number, and Sherwood number, offering comprehensive insights crucial for optimizing performance in engineering applications ranging from thermal management systems to renewable energy technologies. The main finding of this study indicates that the quantitative result reveals that the temperature outline escalates among increasing values of radiation. In contrast, the outlines of a velocity and concentration show a decrease as the values of magnetohydrodynamics increase. In addition, multi-walled carbon nanotubes consume a larger outcome on temperature. A statistical study displays that the thermal stream rate of magnetic oxide-multi-wall carbon nanotubes-water increases from 1.7615 percentages to 7.4415 percentages, respectively, when the volume fraction of nanoparticles rises from 0.01 to 0.05. Future research is important to understanding hybrid nanofluid flows and their applications in thermal engineering systems such as energy systems, nuclear reactors, biomedical applications, electronics cooling, solar thermal systems, chemical processing, and other heat transfer applications where improved thermal performance is crucial. [ABSTRACT FROM AUTHOR]

Renewable multifunctional materials are crucial for advancing industries such as electronics and packaging. This study investigates the potential of graphene nanoplatelet (GNP) and multi-wall carbon nanotube (MWCNT) reinforcement in poly(lactic acid) (PLA)/poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) blends for multifunctional packaging. Employing solvent-free techniques, we conducted a comprehensive analysis of morphological, thermal, mechanical, antimicrobial, and biodegradable properties. High-resolution scanning electron microscopy (FEG-SEM) was applied to evaluate the nanofiller morphologies and the immiscibility between PLA and PHBV, while differential scanning calorimetry (DSC) confirmed crystallinity changes induced by carbon nanomaterials. Mechanical tests demonstrated remarkable enhancements, notably a 30% increase in elastic modulus and 195% in ultimate tensile strength. Antimicrobial assays revealed exceptional effectiveness, especially in GNP-containing nanocomposites. Crucially, biodegradation tests highlighted compatibility with the blend. A Life Cycle Assessment (LCA) underscored significant eco-efficiency, minimizing harmful emissions. These findings emphasize the potential of MWCNT, GNP-reinforced PLA/PHBV nanocomposites for diverse applications and as eco-friendly alternatives to conventional plastics. [ABSTRACT FROM AUTHOR]

Removing polychlorinated biphenyls (PCBs) from subsurface water, soils, and transformer oil is crucial to save the environment from these pollutant materials. Hydrodechlorination (HDC) of PCBs consists of numerous chemical reactions and the simple kinetic models may not provide details for the process. To gain more awareness of the reaction mechanism, in the proposed approach, the isoconversional methods of the Friedman were investigated paralleling other kinetic models of Langmuir‐Hinshelwood (L‐H), Eley‐Rideal (E‐R), pseudo‐first‐order, and pseudo‐second‐order methods. The analysis was validated by laboratory results of HDC of contaminated transformer oil in front of Pd/MWCNTs. The most reactivity was observed for biphenyls with a higher number of chlorines. Finding a suitable model, Akaike Information Criteria were applied. It was attained that Friedman model was the most suitable for monitoring of HDC of PCBs in front of catalyst. Besides, E‐R reaction was appropriate to elucidate the theoretical interpretations of the adsorption and desorption of reactants and chlorinated benzene. [ABSTRACT FROM AUTHOR]

A Mo-Ni/C catalyst was developed and assessed in terms of the decomposition of ethanol to produce multi-wall carbon nanotubes (MWCNTs) and hydrogen. The catalyst utilized different molar ratios of Mo:Ni (1:9, 2:8, and 3:7), with Mo acting as a dopant to enhance the MWCNT yield and Ni acting as the primary active phase for MWCNT formation. Among the tested ratios, the 2:8 Mo:Ni ratio exhibited the optimal performance, yielding 86% hydrogen and high-quality MWCNTs. In addition to hydrogen, the process also generated CO, CH4, and CO2. Gas chromatography (GC) was employed to analyze the influence of the Mo:Ni ratio on gas production and selectivity, while the quality of the resulting MWCNTs was evaluated using SEM, Raman spectroscopy, and TEM analyses. [ABSTRACT FROM AUTHOR]

The external bonding (EB) of fiber-reinforced polymer (FRP) is a usual flexural reinforcement method. When using the technique, premature debonding failure still remains a factor of concern. The effect of incorporating multi-wall carbon nanotubes (MWCNTs) in epoxy resin on the flexural behavior of reinforced concrete (RC) beams strengthened with basalt fiber-reinforced polymer (BFRP) sheets was investigated through four-point bending beam tests. Experimental results indicated that the flexural behavior was significantly improved by the MWCNT-modified epoxy. The BFRP sheets bonded by the MWCNT-modified epoxy more effectively mitigated the debonding failure of BFRP sheets and constrained crack development as well as enhanced the ductility and flexural stiffness of strengthened beams. When the beam was reinforced with two-layer BFRP sheets, the yielding load, ultimate load, ultimate deflection, post-yielded flexural stiffness, energy absorption capacity and deflection ductility of beams strengthened using MWCNT-modified epoxy increased by 7.4%, 8.3%, 18.2%, 22.6%, 29.1% and 14.3%, respectively, in comparison to the beam strengthened using pure epoxy. It could be seen in scanning electron microscopy (SEM) images that the MWCNTs could penetrate into concrete and their pull-out and crack bridging consumed more energy, which remarkably enhanced the flexural behavior of the strengthened beams. Finally, an analytical model was proposed for calculating characteristic loads and characteristic deflections of RC beams strengthened with FRP sheets, which indicated a reasonably good correlation with the experimental results. [ABSTRACT FROM AUTHOR]

This study investigates the comparative effects of carboxyl-functionalized multi-walled carbon nanotube (MWCNT)/water nanofluids and titanium dioxide (TiO2) /water nanofluids in direct absorption parabolic solar collectors. To achieve this, a standard testing apparatus was constructed, and the thermal and exergy efficiencies of the collector were calculated using nanofluids at various concentrations. UV/Vis analysis was used to analyze the radiative properties of the nanofluids, and their thermal conductivity was also measured. Experiments were conducted under laminar flow conditions with flow rates of 20, 60, and 100 liters per hour and inlet temperatures of 20, 30, and 40 °C under real conditions with direct solar irradiation. The highest thermal efficiency recorded for the carbon-based nanofluid was 44.96%, while the titanium-based nanofluid achieved a thermal efficiency of 34.98%. Given the substantial improvement in efficiency compared to the base fluid (distilled water), the combined effect of using both nanofluids was also examined, resulting in a maximum thermal efficiency of 48.77%. The exergy efficiency at the highest flow rate and inlet temperature for the base fluid, TiO2 nanofluid, MWCNT nanofluid, and the hybrid nanofluid were 2.61%, 4.98%, 6.68%, and 7.26%, respectively. The pressure drop of all nanofluids in the absorber tube ranged from 5 to 39.6 Pascals. The studied nanofluids enhance the thermal performance of the system and create low pressure drop, indicating their high efficiency in direct absorption solar collectors. [ABSTRACT FROM AUTHOR]

The use of energy from alternative energy sources as well as the use of waste heat are key elements of an efficient energetics. Adsorption heat storage is a technology that allows solving such problems. For the successful operation of an adsorption heat accumulator, it is necessary to analyze the thermophysical characteristics of the system under the conditions of the operating cycle: heat transfer coefficient adsorbent-metal (α2), overall (U) and global (UA) heat transfer coefficients of heat exchanger. Multi-walled carbon nanotube (MWCNT) composites are very promising for adsorption-based renewable energy storage and conversion technologies. In this work at the stage of heat release, α2 was measured by the large pressure jump (LPJ) method, at the stage of heat storage by large temperature jump method (LTJ), which made it possible to obtain thermophysical characteristics that corresponded to the implementation of the real working cycle as much as possible. The heat transfer coefficients for a pair of adsorbent LiCl/MWCNT—methanol are measured for the first time under the conditions of a daily heat storage cycle both at the sorption stage (α2 = 190 W/m2K) and at the desorption stage (α2 = 170 W/m2K). [ABSTRACT FROM AUTHOR]

An ultrasensitive sandwich-type electrochemical immunosensor for pro-gastrin-releasing peptide (ProGRP) detection was constructed based on PtCu nanodendrites functionalized Au/polyaniline nanospheres (Au/PANI@PtCu). The prepared Au/PANI@PtCu nanocomposites not only possessed excellent electro-catalytic activity of H2O2 reduction due to the synergistic effect between the Au/PANI and PtCu NDs but also provided large specific surface area for detection of antibodies (Ab2) immobilization. In addition, Au nanoparticles encapsulated multi-wall carbon nanotubes (AuNPs@MWCNTs) were also applied to modify the glassy carbon electrode interface for loading numerous capture antibodies (Ab1). In the presence of target ProGRP, a sandwich-type electrochemical immunosensor showed a strong current response from the electro-catalysis of Au/PANI@PtCu toward H2O2 reduction. Benefiting from the exceptional electro-catalytic performance of Au/PANI@PtCu and the high conductivity of AuNPs@MWCNTs, the sandwich-type immunoassay exhibited remarkable sensitivity in detection. The linear range extended from 100 fg/mL to 10 ng/mL, while achieving an impressively low limit of detection of 77.62 fg/mL. [ABSTRACT FROM AUTHOR]

Abstract The use of energy from alternative energy sources as well as the use of waste heat are key elements of an efficient energetics. Adsorption heat storage is a technology that allows solving such problems. For the successful operation of an adsorption heat accumulator, it is necessary to analyze the thermophysical characteristics of the system under the conditions of the operating cycle: heat transfer coefficient adsorbent-metal (α2), overall (U) and global (UA) heat transfer coefficients of heat exchanger. Multi-walled carbon nanotube (MWCNT) composites are very promising for adsorption-based renewable energy storage and conversion technologies. In this work at the stage of heat release, α2 was measured by the large pressure jump (LPJ) method, at the stage of heat storage by large temperature jump method (LTJ), which made it possible to obtain thermophysical characteristics that corresponded to the implementation of the real working cycle as much as possible. The heat transfer coefficients for a pair of adsorbent LiCl/MWCNT—methanol are measured for the first time under the conditions of a daily heat storage cycle both at the sorption stage (α2 = 190 W/m2K) and at the desorption stage (α2 = 170 W/m2K).

In this work, the effect of Multi-Wall Carbon Nanotubes (MWCNTs) addition on the materials shielding properties against Gamma radiation with an energy of 662 keV from a 137Cs source is investigated. The linear attenuation coefficient of MWCNTs-based materials (gelatin-water mixture) with MWCNTs concentrations of 0%, 5%, and 10% is measured. To isolate the contribution of the MWCNTs unique structure to the shielding capabilities, samples with the same concentrations of activated carbon were fabricated and their linear attenuation coefficients were obtained. Also, the linear and the mass attenuation coefficients are obtained theoretically for the same concentrations using the XCOM program and compared with measured values. It is found that the addition of MWCNTs by 5% or 10% has increased the linear attenuation coefficient by around 5% when compared to the same concentrations of activated carbon. This increase in the shielding apabilities against gamma radiation can be related to the interaction of gamma radiation with the extraordinary geometry and structure of MWCNTs.

The magnetic susceptibility features of PMMA/MWCNT nanocomposite were determined after they have derived by ATRP method. The magnetic susceptibility feature of the nanocomposite has depended on the specific synthesis conditions. Their results were compared with each other. The magnetic susceptibility of this nanocomposite has been tuned depending on the concentration of the MWCNTs. The nanocomposite has offered various opportunities for the services and tools with the effect creating a paramagnetic environment to perform different slight changes at magnetic activities where the magnetic field entered this material. The slight responce to paramagnetic ambient in low temperature was suitable for the cost-effective and efficient construction of magnetic devices (magnetic resistive devices, etc.). [ABSTRACT FROM AUTHOR]

A non-invasive ultrasonic transmission method was applied to on-line monitor the curing behavior of the nanocomposites based on epoxy matrix. Effects of dispersion and interfacial adhesion of the nanofiller on high frequency dynamic mechanical properties during curing process of the nanocomposites were discussed. The typical nanofillers, multi-wall carbon nanotubes (p-MWCNTs) were selected, which were doped with graphene oxides (GOs), and dispersed in epoxy resin. By measuring the velocity and attenuation coefficient of longitudinal ultrasonic waves throughout the entire curing cycle, the longitudinal storage modulus and loss tangent of the epoxy nanocomposites were obtained. And the curing kinetics of the epoxy matrix nanocomposites was analyzed based on the Hsich non-equilibrium fluctuation theory. The results proved that enhanced dispersion and interfacial bonding of the GO-MWCNTs with epoxy improved dynamic mechanical properties of the epoxy matrix nanocomposites, while made curing process accelerated. The proposed ultrasonic monitoring method could accurately evaluate the curing process of epoxy-matrix nanocomposites. In conclusion, this research offered a practical effective measurement method for monitoring of curing process of the thermosetting resin matrix nanocomposites. [ABSTRACT FROM AUTHOR]

Solvent-resistant nanofiltration (SRNF) membranes have excellent applications in wastewater treatment, such as organic solvent recovery and water purification. However, the high performance with high solvent permeability passing through the membrane is still a big challenge. We prepared polyimide (PI) SRNF membranes with highly efficient oriented nanochannels via vacuum-assisted interfacial polymerization and magnetic field arraying magnetized functionalized multi-walled carbon nanotubes (MWCNTs). This prepared composite membrane got a molecular weight cutoff of around 600–800 Da, significantly improving the permeability but no change in rejection performance. When MWCNTs were magnetically oriented, the permeability raised from 7.8 to 15.9 L/m−2 h−1 bar−1, which was 103% higher than that of the non-arrayed composited membrane. The stability test illustrated that the permeability rose slightly, but the rejection rate of the CaSO4 solution was kept at 92–94% after being immersed in polar organic solvents for 48 h. This work aimed to design an innovative method for preparing a high-performance SRNF membrane that introduced an arranged nanochannel. [ABSTRACT FROM AUTHOR]

Blend membranes were prepared based on sulfonated poly (ether ether ketone) (SPEEK) and poly (etherimide) (PEI) using different amounts of multi-wall carbon nanotubes (MWCNTs) (up to 2 wt%). PEEK has been sulfonated directly to reach 70 % degree of sulfonation. The manufactured membranes were examined by X-ray diffraction (XRD), scanning field emission electron microscopy (FESEM), Fourier transformed infrared spectroscopy (FTIR). The effect of the composition of SPEEK / PEI on membrane selectivity was investigated under different feed pressures (2 to 8 bar) and temperatures (25 to 55 °C). The values of selectivity and gas permeability were varied between the value of the individual polymers, fluctuating systematically with SPEEK / PEI content variation in the blends. TGA and tensile tests result obtained for prepared membranes shown that the hybrid membrane had good thermal and mechanical properties. The addition of MWCNTs to the blend led to simultaneously improve the selectivity and permeability of the pair gases of CO2 and CH4. The permeability of CO2, as well as CH4/CO2 selectivity for the membrane with the same weight of SPEEK and PEI, and 1 wt% of MWCNTs (coded SP55M1) experienced an increase of about 22 % compared with the neat membrane. Molecular dynamics simulations (MDS) were performed by employing the COMPASS force field to estimate the diffusivity of CH4 and CO2 gases through selected membranes. At last, with compared to the obtained experimetal data, the optimized nanocomposite membrane, integrated with MWCNTs was efficient, which makes it promising platform to separate mixed gase flows of CO2 and CH4 and other related environmental processes.

In this study, a new in-loop hybrid manufacturing method is proposed for fabricating multi-walled carbon nanotube (MWCNTs)/polylactic acid (PLA) composites. Molecular dynamics simulations were conducted in conjunction with experiments to reveal the mechanism of the proposed method for improving the interfacial performance of MWCNTs/PLA. The superposed gradients in the PLA chain activity and conformation due to the plasma-actuating MWCNTs promoted intermolecular interaction and infiltration between the MWCNTs and PLA chains, forming an MWCNTs-stress-transfer bridge in the direction perpendicular to the interlayer interface, and finally enhancing the performance of the composites. The experimental results indicated that the interfacial shear strength of the specimen fabricated using the proposed method increased by 30.50% to 43.26 MPa compared to those without the addition of MWCNTs, and this value was 4.77 times higher than that of the traditional manufacturing method, demonstrating the effectiveness of the proposed method in improving the interfacial properties of MWCNTs/PLA composites. [ABSTRACT FROM AUTHOR]

Conductive polymeric materials are commonly obtained by adding conductive nanoparticles to blends of immiscible polymers that form a cocontinuous morphology. However, during processing, morphology changes, affecting material properties. This study investigates the impact of steady shear deformation on the morphological and electrical properties of a model system consisting of polypropylene/polystyrene/multiwall carbon nanotubes (MWCNTs). The findings reveal that the deformation results in the coarsening of the blend morphology and disruption of the electrical network, increasing both the rheological and electrical percolation threshold concentrations. The evolution of both electrical and morphological properties depends on MWCNT concentration, strain amplitude, and shear rate. The MWCNT concentration, below a certain level, leads to a disruption in electrical conductivity at high shear rates. However, if the MWCNT concentration is above 1 wt. %, the balance between filler network breakup and nanoparticle diffusion is maintained, resulting in stable electrical conductivity and morphology. [ABSTRACT FROM AUTHOR]

This manuscript presents preliminary results on the cement paste potential, with and without carbon nanomaterials, to heal high-temperature cracks. Cement paste beams were subjected to thermal loading of 200°C and 400°C after 28 days of water curing. High temperature caused the formation of microcrack networks on the specimen’s surface. Self-healing was achieved by exposing the cracked samples to cyclic water immersion. The efficiency of the process was evaluated based on the crack closure and mechanical properties recovery after 24 days. The results indicated a distinct dependence of the healing on the loading temperature. Carbon nanotubes had a positive effect on self-repair efficiency.

This study aimed to computationally examine the effect of the average diameter of multiwall carbon nanotubes (MWCNTs) on the hydrothermal properties of a square cavity. A conventional square cavity filled with MWCNT–water was used for the experiment. The left and right walls of the cavity are maintained as hot and cold respectively, whereas the top and bottom walls were assumed to be adiabatic. Mathematical models were developed using the Navier–Stokes equations by applying the thermophysical properties of the MWCNT–water nanofluid. A newly proposed correlation between the effective thermal conductivity and the diameter of carbon nanotube was utilized to analyze the impact of the average diameter on the natural convection of nanofluid inside the cavity. The governing equations were non-dimensionalized using suitable variables and then solved using the Galerkin finite element technique. The combined effects of the Rayleigh number (103

Graphene-related materials (GRM) are promising materials to improve mechanical, electrical, and optical polymer properties. Adding multi-wall carbon nanotubes (MWCNT) on GRM nanocomposites promotes synergistic effects on its electrical properties and electromagnetic interference shielding effectiveness (EMI SE). This study focused on evaluating the addition of MWCNT on three different polycarbonate (PC)/acrylonitrile butadiene styrene (ABS)/GRM nanocomposites. These hybrid nanocomposites were prepared by melt mixing using extrusion and injection-mold processes. The morphologies of the nanocomposites were evaluated by field emission gun scanning electron microscopy (FEG-SEM), and their proprieties were characterized by X-ray diffraction (XRD), oscillatory rheological, dielectric spectroscopy, and EMI SE analyses. The electrical behavior of all hybrid nanocomposites was anisotropic due to the injection-molded preparation process. The lateral size, thickness, and production method of the GRM were indicated to be critical factors for the electrical and EMI SE behaviors of these composites. The nanocomposites with GRM2, which had the smallest lateral size and thickness (graphene nanoplatelets), promoted total attenuation levels around 20 dB with 1.5 wt% of MWCNT, matching the EMI SE required for some commercial applications. Graphical Abstract [ABSTRACT FROM AUTHOR]

Polyethylene glycol (PEG)-based nanofluids possess several unique properties that make them suitable for various applications. To utilize them on an industrial scale, it is crucial to understand their flow characteristics in different processing equipment. This article presents an investigation of the boundary layer flow of viscoelastic nanofluids over a moving wedge and plate, utilizing the Burger model with Maxwell representation for heat and mass transfer characteristics. The nanofluids utilized in this study consist of Polyethylene glycol (PEG) as the base fluid, and multi-wall carbon nanotubes (MWCNTs) as nonmaterial with a nanoparticle volume fraction ranging from 0.05% to 0.5%. Experimental data were collected in the form of storage (elastic) and loss (viscus) moduli against angular frequency, and mathematical expressions were derived to model this data at various nanoparticle volume fractions. These expressions were then incorporated into the flow equations, which were solved subject to appropriate boundary conditions using analytical techniques. The resulting velocity and temperature profiles, under the influence of nanoparticle volume fraction, are presented graphically. Additionally, physical quantities such as velocity and thermal boundary layer thickness, displacement, and momentum thickness were calculated numerically and presented in tabulated form. The findings of this study indicate that increasing nanoparticle volume fraction results in a decrease in the velocity profile and an increase in the temperature profile. [ABSTRACT FROM AUTHOR]

The Ti6Al4V is an eminent material by its high strength, dimensional stability, lower weight and corrosion resistance. Its lower thermal conductivity leads to poor machinability by exhibiting metallurgical alterations. This article discusses the details of dry, wet, cryogenic, minimum quantity lubrication and hybrid cooling methods in the milling of Ti6Al4V. Dry cooling has a worse acute effect on tool life and surface quality by thermal degradation. The widespread high-pressure cooling controls heat dissipation, but cutting tools are affected by chipping and adhesion under long-run milling. In the first instance, cryogenic cooling like liquid nitrogen and liquid carbon dioxide assisted cooling shows excellent tool life and surface integrity; however, excessive uncontrolled chilling and abnormal lubrication affect milling performance. Minimum quantity lubrication with nanoparticles and their combination with multi-wall carbon nanotubes improves the machinability by balanced cooling and lubrication under the concept of green manufacturing engineering. Indirect hybrid cryogenic cooling is a new era in superalloy's cooling methods for long-run applications. The prime drive of this review is to formulate a bridge between cooling and performance under sustainability concerns and propounds the hybrid nanofluids and indirect hybrid cryogenic cooling being the future of Ti6Al4V milling under the mapping of sustainable scale. [ABSTRACT FROM AUTHOR]

Hybrid nanofluids provide better thermal network, mechanical resistance, good aspect ratio and thermal conductivity rather than usual/mono nanofluids. The hybrid nano-composition of multi-wall carbon nanotubes and nickel zinc ferrites possesses superior thermal properties and embellished heat transfer characteristics. The main concern, in this paper, is to examine the novel thermal aspects of water based pure nanofluid (MWCNTs) and hybrid nanofluid (MWCNTs-NiZnFe2O4). The prominent effects of viscous dissipation, motile gyrotactic microorganisms and activation energy have also been taken into account. The other aspect of the study is also to interpret the flow features of hybrid nanofluids subject to Darcy-Forchheimer medium. The characteristics of both hybrid and usual case of nanofluids are covered in this analysis. The governing model problem comprising of coupled and highly non-linear system of equations is treated numerically via a persuasive numerical technique named “Successive over Relaxation” method. A numerical comparison not only validates the code but also found to be in a good correlation with the earlier ones. It can be deduced from the outcomes of the present study that higher levels of Peclet number cause a decrease in the density distribution of motile microorganisms. For the higher values of Forchheimer parameter, lower will be the velocity of fluid and higher will be the shear stress in either, pure or hybrid, case of nanofluids.

Considering the economic benefits and environmental pollution, it is of great significance to recover rare earth elements from wastewater. In this article, the modified bacterial cellulose is the raw material, and multi-wall carbon nanotubes are added to construct together. The ion imprinting technology is introduced to prepare a silicon-based modified film for the recovery of Er(III) and selectively adsorption function of Er(III) in experiments. The maximum adsorption amount of modified carbon nanotube silicon bacterial cellulose composite imprinted membrane can reach 46.52 mg L−1, and the adsorption capacity is greatly improved compared to other methods that of the non-imprinted membrane. The adsorption efficiency of Er(III) can reach 92%. [ABSTRACT FROM AUTHOR]

In complex environmental substance monitoring, the simultaneous detection of single and multiple substances with high sensitivity has been a research focus in the field of electrochemical sensors. Rational selection of appropriate dopants to optimize the electrode material is crucial in this regard. In this work, we employed a multi-doping strategy to effectively enhance the electrocatalytic performance of multi-walled carbon nanotubes (MWCNTs). By doping Ni/NiC x onto MWCNTs, we successfully constructed a heterojunction material (Ni/NiC x -N-MWCNTs). The successful doping of Ni/NiC x allows for the synergistic effects of multiple elements. Ni/NiC x serves as a conductive bridge, forming a three-dimensional network of nanotubes, which effectively reduces the aggregation of carbon nanotubes, exposes more active sites, and enhances electrocatalytic activity. The electrochemical sensor based on Ni/NiC x -N-MWCNTs demonstrated high sensitivity, selectivity, and simultaneous electrochemical detection for acetaminophen (1–150 μM, limit of detection (LOD)=0.56 μM) and dopamine (1–80.0 μM, LOD=0.19 μM). Its excellent reproducibility (relative standard deviation (RSD)=2.01 %) and interference resistance provide Ni/NiC x -N-MWCNTs with significant advantages over other electrode materials, indicating a promising application potential. [Display omitted] • Ni/NiC X -N-MWCNTs heterojunction material is fabricated by doping with Ni/NiC X. • Ni and N co-doping exerts synergy effect to improve electrochemical activity. • The electrochemical sensor shows highly-sensitive determination of APAP and DA. • The excellent repeatability and anti-interference can be obtained in real samples. [ABSTRACT FROM AUTHOR]

Icing hazards often cause severe mobility concerns, safety risks, and even accidents in modern industries. Various ice mitigation strategies have been employed. Electro-thermal heating approach is a popular measure for ice protection, in which heat is generated electrically by internal components and then transferred to the outer surface for anti-icing and de-icing operation. Given the increasing usage of composites in aircraft structures, self-heating fibre reinforced polymer composite has been studied as an ice protection solution for the new generation aircraft. The present work focuses on improving electrical characteristics of carbon nanotube (CNT) based buckypaper (via surface functionalization) and the heating performance with an ice-phobic resin. The results indicated that surface functionalization of multi-wall carbon nanotubes (MWCNTs) was effective in obtaining MWCNT buckypaper (CNP) with improved electrical conductivity. The de-icing test confirmed the electro-thermal heating performance of the CNP based composite in a climate chamber at −20°C. The utilisation of surface modified MWCNTs in self-heating composites could be a promising strategy for maintaining lightweight and efficiency for electro-thermal systems to mitigate icing hazards. [ABSTRACT FROM AUTHOR]

In a proton-exchange membrane water-electrolysis system, performance is greatly affected by the anode materials and operation modes. Moreover, high voltages allow greater hydrogen production as well as the potential of creating ozone for green disinfection. However, after switching off power and restarting, a big decrease in performance drop as well as hydrogen/ozone generation. In this study, different additives—multi-wall carbon nanotubes, surface-modification graphene, reduction graphene oxide, and graphene oxide—are adopted and mixed with PbO 2 and to create anode catalyst ink. The characteristics of the anode catalysts are investigated with voltage-current test, interruptive power supply, electrochemical impedance spectroscopy and high voltage accelerating tests. The results show that the anode of MEA with additive, multi-wall carbon nanotubes or multi-wall carbon nanotubes plus surface-modification graphene, lead to twice higher performance. Further, anode of MEA with additive, multi-wall carbon nanotubes, multi-wall carbon nanotubes plus graphene oxide, and multi-wall carbon nanotubes plus reduction graphene oxide, displays better restoration (34–36%↓). • The PbO 2 with additives as anode performs two times higher than pure PbO 2. • Additives including G, GO, and RGO show steady operation in the harsh environment. • The anode with PbO 2 composed of carbon nanotube shows uniform distribution and porous structure. [ABSTRACT FROM AUTHOR]

Porous 3D composite materials are interesting anode electrodes for single chamber microbial fuel cells (SCMFCs) since they exploit a surface layer that is able to achieve the correct biocompatibility for the proliferation of electroactive bacteria and have an inner charge transfer element that favors electron transfer and improves the electrochemical activity of microorganisms. The crucial step is to fine-tune the continuous porosity inside the anode electrode, thus enhancing the bacterial growth, adhesion, and proliferation, and the substrate's transport and waste products removal, avoiding pore clogging. To this purpose, a novel approach to synthetize a 3D composite aerogel is proposed in the present work. A 3D composite aerogel, based on polydimethylsiloxane (PDMS) and multi-wall carbon nanotubes (MWCNTs) as a conductive filler, was obtained by pouring this mixture over the commercial sugar, used as removable template to induce and tune the hierarchical continuous porosity into final nanostructures. In this scenario, the granularity of the sugar directly affects the porosities distribution inside the 3D composite aerogel, as confirmed by the morphological characterizations implemented. We demonstrated the capability to realize a high-performance bioelectrode, which showed a 3D porous structure characterized by a high surface area typical of aerogel materials, the required biocompatibility for bacterial proliferations, and an improved electron pathway inside it. Indeed, SCMFCs with 3D composite aerogel achieved current densities of (691.7 ± 9.5) mA m−2, three orders of magnitude higher than commercial carbon paper, (287.8 ± 16.1) mA m−2. [ABSTRACT FROM AUTHOR]

This study presented the details of multi-wall carbon nanotubes (MWCNTs)-modified resin injection repair aiming to enhance the mechanical properties, considering the flexural and compression behavior. The resin injection of epoxy resin dispersed with MWCNTs (0.1, 0.3, and 0.5 wt.%) as low viscosity resin that delaminated composite structure repair was conducted using a developed vacuum-based resin injection system at 80°C with constant injection pressure. The quasi-static indentation (QSI) method with a circular window was applied to create the barely visible impact damage (BVID) in the laminate specimen and thus obtain the delamination damage with reproducibility. The flexural strength and compression after impact (CAI) test were conducted on repaired carbon fiber reinforced laminates to assess the effect of the dispersion of the MWCNTs in the epoxy resin injection approach compared to neat epoxy resin. The mechanical test results exhibited that the recovery rate was better improved in the case of the modified resin infiltration approach in laminate composites dispersed with nanoparticles. It was attributed to their more enhanced strengthening mechanisms under effective interaction in mixed interface of fiber-matrix-MWCNTs, mainly attributing to bridge connection and stronger interfacial adhesion properties. [ABSTRACT FROM AUTHOR]

We investigated the use of graphite as primary filler and multi-walled carbon nanotubes (MWNTs) as secondary filler in chitosan-based polymer electrolyte film which aided in increasing the electrical conductivity of the prepared film. The addition of a small amount of MWNTs as secondary filler increased the A.C. conductivity from 2.6 × 10–4 to 1.4 × 10−3 S/cm due to the formation of conductive layers by it. The co-sensitized dye obtained from pomegranate and moss (1:1) is evaluated for the fabrication of dye-sensitized solar cells. In place of nanostructured TiO2-based photoanode, we admixed TiO2 with indium oxide (In2O3) to improve the spectral response of TiO2 for obtaining better efficiency. The use of this polymer electrolyte film along with co-sensitized natural dye and admixed photoanode helped in the fabrication of a highly efficient dye-sensitized solar cell (DSSC) with around 3.8% efficiency. [ABSTRACT FROM AUTHOR]

Nowadays, Carbon nanotubes have been widely used in industry, engineering, science, and many other fields. The CNTs are formed of two classes, the first class is single-wall (SWCNTs) and the second is multi-wall (MWCNTs). Their synthesis is implemented using various methods such as Arc discharge and chemical vapor deposition processes. These methods produce stripping carbon atoms which exist as carbon whiskers formed as a side product in the air that could be breathed by human in the factories. These broad applications directly affect the human health because they are related to important areas involving direct influence to human health for example, in the pharmaceutical and food industries. One of the main risks facing the use of carbon nanotubes is to study the toxicity and the possibility of causing serious diseases such as lung cancer and skin cancer. As mentioned in the results of published researches explored in this review, especially those related to studying the effect of carbon nanotube on rat groups, for instance, direct exposure to specific amounts of carbon nanoparticles has caused serious complications, fibrosis and the emergence of carcinogenic infections in lung cells. Studies have shown that the toxicity of carbon nanotubes exceeded the toxicity of known toxic compounds such as quartz. These results, which have been discussed in the research, indicate that nanoparticles are considered as a toxic substance and we should be very cautious when dealing with them and take the necessary precautions in the laboratory especially those related to human health and food industries.

Polymers have a wide application. Fused deposition modeling (FDM) is a ubiquitous additive manufacturing (AM) technique that enables producers to manufacture polymer parts in a cost-effective way. However, the bed size limitation in 3D printers restricts their applicability in a variety of industries; therefore, it seems essential to find a great approach to join 3D-printed parts. Friction stir welding (FSW) is an excellent solution to join 3D-printed parts to overcome bed size limitation. A friction welding joint is referred as interface, fusion, or bond and is a point or edge where two or more pieces are joined together by friction. In the first stage, the aim of this investigation is to study the effect of groove shape and volume fraction of the multi-wall carbon nanotube powder on the mechanical properties including angular distortion, tensile and flexural strength, and hardness as well as electrical properties of ABS parts manufactured by fused deposition modeling machine. Secondly, the impact of those parameters on tensile strength via two artificial neural networks (ANN and GMDH) was investigated. The results showed that not only greater tensile and flexural strength was achieved thanks to the carbon nanotube, but also hardness was improved. The lower amount of powder and square groove shape leads to greater tensile and flexural strength. The square groove shape and more volume fraction of MWCNTS also gave rise to lower angular distortion. The positive influence of adding MWCNTs on joining 3d-printed parts via FSW was not restricted to mechanical properties and adding only 4.16% of MWCNTs showed a significant increase in electrical properties. Finally, both ANN and GMDH have shown excellent results (R-value of 0.94 and 0.93 with the error of 8 and 20%, respectively) in predicting the tensile strength of welded specimens.

A single bubble absorption column was used to examine the effect of hydrodynamic on carbon dioxide (CO2) and hydrogen sulfide (H2S) absorption in pure water and water-based nanofluids dispersed with neat, and OH and NH2 functionalized multiwall carbon nanotubes (MWCNTs). Sodium dodecyl sulfate (SDS) was used as a surfactant and stabilizer. The maximum absorption of CO2 and H2S were found to be 0.0038 mmol/m2·s and 0.056 mmol/m2·s using NH2-MWCNTs /nanofluid with 0.5 wt% content, respectively. The diffusion coefficients of gases into the nanofluids were computed by using an equation attained based on Dankwert’s theory. A last, an empirical correlation was proposed to determine the Sherwood number for the absorption of the aforementioned gases into the nanofluids.

An electrochemical approach is presented based on multiwall carbon nanotubes (MWCNTs) and neodymium(III) hydroxide (Nd(OH)3) nanoflakes for detection of bovine serum albumin (BSA). The materials were characterized morphologically (XRPD, SEM, and HR-TEM) and electrochemically (DPV, EIS). The MWCNTs@Nd(OH)3 composite was used as support for bovine serum albumin polyclonal antibody (anti-BSA). After the antibody immobilization on the electrochemical platform and antigen/antibody binding time (optimum 60 min), the proposed approach shows a linear voltammetric response toward BSA concentration in the range 0.066 to 6.010 ng mL−1 at maximum peak potential of 0.13 V (vs. Ag/AgCl). Limit of detection (LOD) and limit of quantification (LOQ) were 18 pg mL−1 and 61 pg mL−1, respectively. The precision of the method calculated as relative standard deviation (RSD) of five independent measurements was better 3%. The selectivity of the optimized method regarding structurally similar proteins (human serum albumin and human hemoglobin), ions (Na+, K+, Ca2+, and NO2−), or compounds (glucose, ascorbic acid, dopamine, uric acid, paracetamol, and glycine) was found to be satisfactory, with the current changes of less than 5% in the presence of up to 1 × 105 times higher concentrations (depending on the compound) of the listed potential interfering compounds. Practical applicability of immunosensor for BSA determination in cow whey sample, with recovery values in the range 97 to 103%, shows that the developed method has high potential for precise and accurate detection of BSA, as well as exceptional miniaturization possibilities for on-site and equipment-free sensing. [ABSTRACT FROM AUTHOR]

In this study, a magnetic solid-phase extraction method was developed based on multi-wall carbon nanotubes decorated by magnetic nanoparticles (Fe3O4) and cadmium sulfide nanoparticles (Fe3O4@MWCNT-CdS) for trace extraction of cefixime and tetracycline antibiotics from urine and drug company wastewater. The adsorbent features were characterized by Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FESEM), and energy dispersive X-ray analysis (EDX). Various effective parameters on the sorption and desorption cycle, such as sorption time, the mass of adsorbent, pH, salt addition, and material ratio, were investigated and optimized. The data were evaluated using isotherm models, and experimental data were well-fitted to both Langmuir (R2 = 0.975) and Freundlich (R2 = 0.985) models. Moreover, kinetic of reaction was agreement with pseudo-second-order (R2 = 0.999) as compared pseudo-first-order (R2 = 0.760). The maximum adsorption capacity for tetracycline and cefixime was achieved at 116.27 and 105.26 mg·g−1, respectively. Hence, the prepared adsorbent can be used as an alternative material for enhanced determination of pharmaceutical substances in biological fluids. [ABSTRACT FROM AUTHOR]

This paper presents the results of studying the effect of the multi-wall carbon nanotube addition on physical and mechanical properties of aluminum alloy AMg5Mn obtained using the mechanical mixing technology. The analysis of the experimental and reference samples has shown that the use of microquantities of uniformly distributed multi-wall carbon nanotubes (0.1 wt.%) leads to an increase in tensile strength of the composite by at least 15%. [ABSTRACT FROM AUTHOR]

Condensed particles in the internal flow field of a solid rocket motor can cause serious erosion to thermal insulations under overload flight condition. Multi-walled carbon nanotubes (MWCNTs) can improve erosion resistance of insulations but at the cost of reduced thermal insulation performance. In this study, MWCNTs were precoated with pyrolytic carbon via chemical vapor deposition to reduce their thermal conductivity. Further, ethylene propylene diene monomer insulations reinforced with different contents of MWCNTs and precoated MWCNTs were prepared. Moreover, their ablation performances under simulated overload ablation conditions were tested and compared. Experimental results show that precoated MWCNTs can not only improve thermal insulation performance but also significantly increase particle erosion resistance of ethylene propylene diene monomer insulation materials. Charring ablation rate of the formula with 10phr precoated MWCNTs is 44.3% lower than that of basic formula and 41.6% lower than that of the formula with 3phr MWCNTs which has the same pure MWCNTs content. The char layers of MWCNTs reinforced formulas are more complete than basic formula, indicating that MWCNTs can improve char layer structure under particle erosion condition. The precoated MWCNTs can also promote the CVD reaction of pyrolysis gas in char layers during ablation, decreasing the porosity of char layers, which can increase the particle erosion resistance of insulation. • Particle resistance of EPDM insulation was studied with the overload simulation SRM; • EPDM insulation with less quantity of precoated MWCNTs retain good particle resistances; • Precoated MWCNTs can promote CVD reaction of pyrolysis gas within char layers. [ABSTRACT FROM AUTHOR]

In this investigative study, the Taguchi design (L9) of experiments with TOPSIS multi-objective optimization is used for the robot nanopainting. The optimization objective is to maximize the film glue individually and minimize the surface blemishes and film thickness by varying the IRB 1410 robot painting parameters, such as the robot speed, pressure, and distance. The multi-wall carbon nanotube is infused into the paint materials using the ultrasonication process, and the mechanical properties are analysed with a comparison to regular paint materials. The virtual robot cycle time analysis is carried out for three different robot pathway patterns, namely linear, zig-zag, and circular. It is then compared with real-time experimental robot nanopaint on cold rolled close annealing steel materials. The obtained results show that surface roughness and thickness are minimized by 54% and 33.4%, respectively, using the robot nano spray coating when compared with regular spray coating. The film adhesive of robot Nano spray coating is maximized by 2.8% more than normal spray coating. A fuzzy logic expert system model is used to evaluate the surface finish characteristics of the nanopaint surface with low prediction error and with 89.2% confidence level. Heat transfer analysis of the robot nano-coated substrate is compared with that of the robot normal-coated substrate. [ABSTRACT FROM AUTHOR]

In this work, a study of the linear viscoelastic properties of co-continuous polypropylene/polystyrene blends filled with multiwall carbon nanotubes (MWCNTs) is presented. The YZZ rheological model [W. Yu et al., Polymer 51, 2091–2098 (2010)] is employed to correlate the rheological behavior of the blends with their microstructure and electrical properties. A test design involving a sequence of small amplitude oscillatory shear and a time sweep (simulating thermal annealing) is used to evaluate the morphology and evolution of electrical properties. It was shown that the YZZ rheological model could be successfully modified to be able to quantify a co-continuous morphology of filled composites. The calculated characteristic domain size was found to be in good agreement with the experimental data obtained via scanning electron microscopy. Furthermore, it is shown that the characteristic domain size slightly decreased after 30 min of thermal annealing. It was shown, as well, that thermal annealing promoted a reduction in the electrical percolation threshold (wt. % MWCNT) from 0.28 to 0.06. [ABSTRACT FROM AUTHOR]

The aim of this article is to analyze the mixed convective Ostwald–de Waele power-law nanofluid flow over vertical frustum of a cone in a non-Darcy porous medium using an efficient numerical technique. The involved power-law nanofluid model utilizes water as the base fluid, and Ti-alloy (Ti6Al4V) and multi-wall carbon nanotubes (MWCNTs) as the nanoparticles. The solution of resultant non-similarity equations subjected to boundary conditions is described using the local non-similarity technique along with an efficient spectral local linearization method. The error estimation is provided to show the efficiency of above-mentioned solution procedure. A detailed explanation about the impact of nanoparticle volume fraction on the dimensionless velocity and temperature profiles along with heat transfer rate and skin friction coefficient is also provided for both the opposing and aiding flow cases. On comparison of the present results in particular cases with the relevant published data, it is assured that this method gives highly accurate outcomes for this kind of very complex fluid flow problems. The domination of dilatant nanofluid over pseudo-plastic nanofluid in both the aiding and opposing flow cases is noticed for velocity profiles, and the velocity is decreased with an increment in the nanoparticle volume fraction. Also, the variation in profiles with a streamwise coordinate ξ shows non-similar nature of the problem. The use of Ti-alloy and MWCNTs in this work makes it very profitable in various important sectors like aerospace and medical sector. [ABSTRACT FROM AUTHOR]

In this study, polypropylene (PP) and multi-walled carbon nanotubes (MWCNTs) are used to coat stainless steel (SS) wrapped yarns, the product of which is then fabricated into conductive textiles. Afterwards, the tensile properties, surface resistivity, and electromagnetic shielding effectiveness (EMSE) of conductive textiles are evaluated, thereby determining the influences of the MWCNTs content. The test results show that using MWCNT can effectively improve the mechanical properties of the coated yarns and conductive woven fabrics. In addition, 5 wt % of MWCNT provides the woven fabrics with a lower surface resistivity and higher EMSE. The influences of the lamination angle and number of lamination layers on EMSE are investigated, and the maximum EMSE of −49.89 dB occurs when the lamination angle is 0 °/90 °/0 °. [ABSTRACT FROM AUTHOR]

This study proposes a microfluidic device used for X-/Y-sperm separation based on monoclonal antibody-conjugated magnetic beads, which become positively charged in the flow system. Y-sperms were selectively captured via a monoclonal antibody and transferred onto the microfluidic device and were discarded, so that X-sperms can be isolated and commercially exploited for fertilization demands of female cattle in dairy industry. Therefore, the research team used monoclonal antibody-conjugated magnetic beads to increase the force that causes the Y-sperm to be pulled out of the system, leaving only the X-sperm for further use. The experimental design was divided into the following: Model 1, the microfluid system for sorting positive magnetic beads, which yielded 100% separation; Model 2, the sorting of monoclonal antibody-conjugated magnetic beads in the fluid system, yielding 98.84% microcirculation; Model 3, the sorting of monoclonal antibody-conjugated magnetic beads with sperm in the microfluid system, yielding 80.12% microcirculation. Moreover, the fabrication microfluidic system had thin film electrodes created via UV lithography and MWCNTs electrode structure capable of erecting an electrode wall 1500 µm above the floor with a flow channel width of only 100 µm. The system was tested using a constant flow rate of 2 µL/min and X-/Y-sperm were separated using carbon nanotube electrodes at 2.5 V. The structure created with the use of vertical electrodes and monoclonal antibody-conjugated magnetic beads technique produced a higher effective rejection effect and was able to remove a large number of unwanted sperm from the system with 80.12% efficiency. [ABSTRACT FROM AUTHOR]