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This work is an attempt to evaluate the effect of multi-wall carbon nanotube (MWCNT) reinforcement on the properties of non-crimp fabric (NCF) carbon fiber-reinforced polymer hybrid composite (CFRP). MWCNT NCF-CFRP plates were produced by vacuum infusion. Epoxy-MWCNT mixtures were prepared by adding a surfactant, Triton-X 100, and ethanol and mixing ultrasonically. The plates were subjected to thermal and electrical conductivity, DSC and FT-IR characterizations, and tensile testing. SEM image analyses evaluated tensile fracture surfaces. Results showed that 0.5 wt% MWCNT-reinforced nanocomposite samples exhibited better tensile properties than pure NCF-CFRP composites and other nanocomposite samples. The 1.5% MWCNT reinforced sample was the best conductor at all temperatures. The temperature increases also increase the conductivity. However, the conductivity value of 0.5% MWCNT reinforced material increased significantly at low frequencies such as 100–10,000 Hz. The heat reaction of the 0.5 wt% MWCNT nanocomposite was also a bit higher than that of 1–1.5 % wt MWCNT nanocomposites, indicating a decrease in the cure. [ABSTRACT FROM AUTHOR]

This study explores the development of electrically conductive bio‐based textiles by investigating the fabrication and structural characterization of multi‐walled carbon nanotubes (MWCNT) and graphene nanoplatelets (GNP) coatings on viscose fabric (VF) using two bio‐based binders. The research employs various analytical techniques, including Fourier transform infrared (FTIR) analysis, water contact angle (WCA) measurements, optical microscopy, air permeability tests, field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), mechanical property evaluations, and electrical conductivity tests. Optimization of the coating process revealed that a binder concentration of 20 g L−1 combined with six dip‐dry cycles offered the optimal balance of conductivity, water contact angle (WCA), and coating uniformity. The study found distinct correlations between binder type and properties such as WCA, air permeability, surface coverage, and thermal stability. The incorporation of carbon‐based materials significantly enhanced the electrical conductivity of the samples, with MWCNT‐coated fabrics demonstrating higher conductivity compared to those coated with GNP. Furthermore, the inclusion of a hot‐pressing step further improved the electrical conductivity. MWCNT‐coated fabrics exhibited excellent electrical heating properties, generating temperatures up to 130 °C with a 10 V DC voltage. These findings advance the field of e‐textiles, presenting straightforward, bio‐based methods for creating highly conductive textiles with good mechanical properties and thermal stability. [ABSTRACT FROM AUTHOR]

AbstractThe present study investigates the mechanical properties of AlP0507-based metal matrix composites reinforced with multi-walled carbon nanotubes (MWCNTs) and rice husk (RHA) using experiments and numerical simulation. To achieve this goal, an AlP0507-based MWCNT/RHA hybrid metal matrix composite was fabricated by stir casting method. Subsequently, microstructural analysis using field emission scanning electron microscopy (FESEM) and EDAX was carried out for different weight ratios of MWCNTs/RHA. In addition, the tensile, impact, and hardness characteristics of MWCNT/RHA-reinforced aluminum metal matrix composite (AMMC) and hybrid MWCNT/RHA-reinforced aluminum metal matrix composite (HAMMC) were experimentally investigated for different reinforcement weight concentrations. In addition, the tensile, von Mises stress distribution, strain, and deformation behavior of AMMC and HAMMC were numerically investigated using the commercial software Digimat-FE supporting the RVE approach considering particle inclusions. It was also noticed that the optimal addition of RHA/MWCNTs to the AlP0507 melt led to an improvement in the tensile strength, hardness, and impact properties of the composites when compared to the AlP0507 material without any reinforcement. It can also be noticed that after a certain optimal percentage of RHA reinforcement, the tensile strength of AMMC and HAMMC decreases. Further, the examination of the numerical stress distribution facilitates the prediction of the regions that exhibit high levels of stress concentration, potential locations of fracture, or areas where the material may undergo excessive deformation.

Epinephrine (EP) is a very important chemical transmitter in the transmission of nerve impulses in the central nervous system of mammals. Ascorbic acid (AA) is considered to be the most important extracellular fluid antioxidant and has important antioxidant properties in the cell. In this study, a series of transition metal–polyhistidine-carboxylated multi-wall carbon nanotube nanocomposites were synthesized, and their simultaneous catalytic effects on epinephrine and ascorbic acid were investigated. The results showed that nanocomposites based on iron ions had the highest catalytic activity. The prepared biosensor expressed high selectivity toward EP and AA with LOD values of 0.1 μΜ (AA) and 0.01 μΜ (EP), and sensitivity values of 4.18 μA mM−1 with a range of 0.001–5 mM (AA), 50.98 μA mM−1 with a range of 0.2–100 μM (EP), and 265.75 μA mM−1 with a range of 0.1–1.0 mM (EP). Moreover, it showed good stability, good repeatability and high selectivity in real sample detection. This work is a reference for the design of new electrochemical enzyme-free biosensors and the detection of biomarkers. [ABSTRACT FROM AUTHOR]

This study investigated the synergistic effect of carbon black/multi-wall carbon nanotube (CB/MWCNT) hybrid fillers on the physical and mechanical properties of Ethylene propylene diene rubber (EPDM) composites after exposure to high-pressure hydrogen gas. The EPDM/CB/CNT hybrid composites were prepared by using the EPDM/MWCNT master batch (MB) with 10 phr CNTs to enhance the dispersion of CNTs in hybrid composites. The investigation included a detailed analysis of cure characteristics, crosslink density, Payne effect, mechanical properties, and hydrogen permeation properties. After exposure to 96.3 MPa hydrogen gas, the hydrogen uptake and the change in volume and mechanical properties of the composites were assessed. We found that as the MWCNT volume fraction in fillers increased, the crosslink density, filler–filler interaction, and modulus of hybrid composites increased. The hydrogen uptake and the solubility of the composites decreased with an increasing MWCNT volume fraction in fillers. Moreover, after exposure to hydrogen gas, the change in volume and mechanical properties exhibited a diminishing trend with a higher MWCNT volume fraction. We conclude that the hybridization of CB and CNTs formed strong filler–filler networks in hybrid composites, consequently reinforcing the EPDM composites and enhancing the barrier properties of hydrogen gas. [ABSTRACT FROM AUTHOR]

Nanocomposite membranes made of chitosan (Cs) concentrations, and polyvinyl alcohol (PVA) with a fixed ratio of (60:40), then incorporated with different concentrations of multi-walled carbon nanotubes (MWCNTs) (1, 1.5, 2, 2.5, and 3%) were created using the solution cast method. The membranes were identified using UV-vis spectroscopy, Fourier transform infrared (FTIR), and X-ray diffraction (XRD). The results demonstrated that the samples were sufficiently stable, and the interactions between nanoparticles and polymers were generally negligible. XRD patterns showed a crystalline phase of PVA, an amorphous phase of chitosan, and a more crystalline phase as MWCNTs were introduced. In particular, at high percentages of MWCNTs, the dominant phase (002), connected to MWCNTs, was shifted to a higher value. The UV-vis spectroscopy of the sample showed only one absorption peak at about 230 nm and no other peaks. This may be due to transparency in PVA and Cs. The band gap energy decreased when higher percentages of MWCNTs were added to the mixture.

The present study investigates the mechanical properties of AlP0507-based metal matrix composites reinforced with multi-walled carbon nanotubes (MWCNTs) and rice husk (RHA) using experiments and numerical simulation. To achieve this goal, an AlP0507-based MWCNT/RHA hybrid metal matrix composite was fabricated by stir casting method. Subsequently, microstructural analysis using field emission scanning electron microscopy (FESEM) and EDAX was carried out for different weight ratios of MWCNTs/RHA. In addition, the tensile, impact, and hardness characteristics of MWCNT/RHA-reinforced aluminum metal matrix composite (AMMC) and hybrid MWCNT/RHA-reinforced aluminum metal matrix composite (HAMMC) were experimentally investigated for different reinforcement weight concentrations. In addition, the tensile, von Mises stress distribution, strain, and deformation behavior of AMMC and HAMMC were numerically investigated using the commercial software Digimat-FE supporting the RVE approach considering particle inclusions. It was also noticed that the optimal addition of RHA/MWCNTs to the AlP0507 melt led to an improvement in the tensile strength, hardness, and impact properties of the composites when compared to the AlP0507 material without any reinforcement. It can also be noticed that after a certain optimal percentage of RHA reinforcement, the tensile strength of AMMC and HAMMC decreases. Further, the examination of the numerical stress distribution facilitates the prediction of the regions that exhibit high levels of stress concentration, potential locations of fracture, or areas where the material may undergo excessive deformation. [ABSTRACT FROM AUTHOR]

Nanocomposite membranes made of chitosan (Cs) concentrations, and polyvinyl alcohol (PVA) with a fixed ratio of (60:40), then incorporated with different concentrations of multi-walled carbon nanotubes (MWCNTs) (1, 1.5, 2, 2.5, and 3%) were created using the solution cast method. The membranes were identified using UV-vis spectroscopy, Fourier transform infrared (FTIR), and X-ray diffraction (XRD). The results demonstrated that the samples were sufficiently stable, and the interactions between nanoparticles and polymers were generally negligible. XRD patterns showed a crystalline phase of PVA, an amorphous phase of chitosan, and a more crystalline phase as MWCNTs were introduced. In particular, at high percentages of MWCNTs, the dominant phase (002), connected to MWCNTs, was shifted to a higher value. The UV-vis spectroscopy of the sample showed only one absorption peak at about 230 nm and no other peaks. This may be due to transparency in PVA and Cs. The band gap energy decreased when higher percentages of MWCNTs were added to the mixture. [ABSTRACT FROM AUTHOR]

In this study, ZA40/ MWCNT composites were produced by using powder metallurgy technique and hot press method by adding 0,5-1-1,5-2% wt. MWCNT to ZA40 alloy. Powders made with mechanical alloys were sintered by hot pressing for 3 hours under 500 °C and 800 MPa pressure. Wear tests were carried out under 5N and 10N loads in a dry friction environment using the ball-on-disk technique. Weight losses, average friction force, and wear rate of the samples were calculated after wear tests. Morphology, internal structure images, and examination of worn surfaces of the samples were investigated using scanning electron microscopy (SEM). The wear test results show the coefficient of friction of ZA40-2wt. % MWCNT was 0,18 µ (lower than the coefficient of friction of 0,66 µ for ZA40 alloy). The wear rate of ZA40 alloy was almost 6 times higher than ZA40-2 wt. % MWCNT composite. [ABSTRACT FROM AUTHOR]

One of the important issues in urban areas is air pollution which causes respiratory disorders. A signifi cant association between exposure to inhaled particulate matter (PM), mainly ultrafi ne particles, and increased neurological and pulmonary morbidity and mortality was observed in some research. This study aimed to demonstrate the relation between multi-wall carbon nanotubes (MWCNTs) inhalation and the carcinogenic effect of these materials in the brain and lungs. For this purpose, we investigated gene expression in rat brain and lung tissues induced by exposure to MWCNTs. Rats were exposed to MWCNTs in diameters of 10 and 100 nm (pure and impure) at a concentration of 5 mg/m3 . Exposure was done through a whole-body exposure chamber for 5 h/day, 5 days/week for 14 days. After exposure, both brain and lung tissues were isolated to evaluate certain gene expressions including Bax, Bcl2, Rac1, Tp53, Mmp12, and Arc. The results showed that exposure to impure and pure MWCNTs (10 and 100 nm) at a concentration of 5 mg/m3 causes up-regulation or down-regulation of some of these genes. The results suggest that impure and pure MWCNTs (10 and 100 nm) can increase the risk of central nervous system disorders such as Alzheimer’s disease and increase the risk of carcinogenesis in the lung tissues of rats exposed to MWCNTs (Tab. 2, Fig. 2, Ref. 64). Text in PDF www.elis.sk. [ABSTRACT FROM AUTHOR]

Electro-mechanical configurations can be piezo-electric transducers, triboelectric generators, electromagnetic induction, or hybrid systems. Our present study aims at developing energy generation through the piezoelectric principle. Gel-type soft SR with Shore A hardness below 30 was used as a versatile material for an elastomeric substrate. Also, multi-wall carbon nanotube (MWCNT), and diatomaceous earth (DE) were used as reinforcing fillers. This "gel-type" soft SR has crosslinking polymer networks with silicone encapsulated within its structure. Mechanical properties such as modulus or stretchability are of utmost importance for such devices based on "gel-type" soft. From the experiments, some of the mechanical aspect's values are summarized. For example, the stretchability was 99% (control) and changes to 127% (3 phr, MWCNT), 76% (20 phr DE), and 103% (20 phr hybrid). From electro-mechanical tests, the output voltage was 0.21 mV (control) and changed to 0.26 mV (3 phr, MWCNT), 0.19 mV (20 phr DE), and 0.29 mV (20 phr hybrid). Moreover, from real-time biomechanical human motion tests in "gel-type" soft-based composites, a relationship among output voltage from machine to human motions was established. Overall, these configurations make them promising against traditional portable devices such as batteries for small power applications such as mobile phones. [ABSTRACT FROM AUTHOR]

In this study, ZA40/ MWCNT composites were produced by using powder metallurgy technique and hot press method by adding 0,5-1-1,5-2% wt. MWCNT to ZA40 alloy. Powders made with mechanical alloys were sintered by hot pressing for 3 hours under 500 °C and 800 MPa pressure. Wear tests were carried out under 5N and 10N loads in a dry friction environment using the ball-on-disk technique. Weight losses, average friction force, and wear rate of the samples were calculated after wear tests. Morphology, internal structure images, and examination of worn surfaces of the samples were investigated using scanning electron microscopy (SEM). The wear test results show the coefficient of friction of ZA40-2wt. % MWCNT was 0,18 μ (lower than the coefficient of friction of 0,66 μ for ZA40 alloy). The wear rate of ZA40 alloy was almost 6 times higher than ZA40-2 wt. % MWCNT composite.

The spray painting is widely used in automobile industries, marines and navy, etc. Extensive development of research is going in Robotics for painting application. In which it gives the best quality and productivity but also reduces paint consumption during painting. This study will help in identifying the factors affecting the spray coating, environmental and chemical properties. The input factors which directly affects the output are spray gun design, nozzle sizes, the distance between substrate and gun, paint pressure flow, viscosity, flash point, pour point, robot speed, temperature, size of droplets, spray time, overspray. The output factors which we want to minimise are surface roughness, thickness, over-spray, the quantity of spray, operation time, heat transfer, corrosion, cracks, peeling and maximise the film adhesive, and the life span of the substrate. To enhance the quality of substrate, the carbon nanotubes (CNTs), like Multiwall Carbon Nanotubes (MWCNTs), are infused in paint by ultrasonication and magnetic stirrer process while preparing the nanopaint. The nanopaint has mechanical, thermal, electrical, chemical and physical properties. Nanopaint acts as a coolant, anti-corrosion, self-healing, and has less viscosity in nature with high young's modulus. The formation of pores, debris and layers are very less in robot nanospray painting. [ABSTRACT FROM AUTHOR]

The demand for multi-functional elastomers is increasing, as they offer a range of desirable properties such as reinforcement, mechanical stretchability, magnetic sensitivity, strain sensing, and energy harvesting capabilities. The excellent durability of these composites is the key factor behind their promising multi-functionality. In this study, various composites based on multi-wall carbon nanotubes (MWCNT), clay minerals (MT-Clay), electrolyte iron particles (EIP), and their hybrids were used to fabricate these devices using silicone rubber as the elastomeric matrix. The mechanical performance of these composites was evaluated, with their compressive moduli, which was found to be 1.73 MPa for the control sample, 3.9 MPa for MWCNT composites at 3 per hundred parts of rubber (phr), 2.2 MPa for MT-Clay composites (8 phr), 3.2 MPa for EIP composites (80 phr), and 4.1 MPa for hybrid composites (80 phr). After evaluating the mechanical performance, the composites were assessed for industrial use based on their improved properties. The deviation from their experimental performance was studied using various theoretical models such as the Guth–Gold Smallwood model and the Halpin–Tsai model. Finally, a piezo-electric energy harvesting device was fabricated using the aforementioned composites, and their output voltages were measured. The MWCNT composites showed the highest output voltage of approximately 2 milli-volt (mV), indicating their potential for this application. Lastly, magnetic sensitivity and stress relaxation tests were performed on the hybrid and EIP composites, with the hybrid composite demonstrating better magnetic sensitivity and stress relaxation. Overall, this study provides guidance on achieving promising mechanical properties in such materials and their suitability for various applications, such as energy harvesting and magnetic sensitivity. [ABSTRACT FROM AUTHOR]

Flat Plate Solar Collectors (FPSCs) have been widely employed in the production of renewable energy for a significant period. To enhance their thermal performance, the utilization of nanofluids as heat transfer fluids has emerged as a popular approach. However, many research works were only carried out with conventional metal-based nanofluids. This numerical study investigates the effects of incorporating two carbon nanotubes, namely single-walled carbon nanotube (SWCNT)/water and multi-walled carbon nanotube (MWCNT)/water, on the fluidic and thermal performance of FPSC. The Nusselt (Nu) and Stanton (St) numbers, as well as the frictional characteristics, are measured and compared to those of metal-based nanofluid of alumina (Al2O3)/water at volume concentrations up to 1%. It is found that Nu increases with a higher Reynolds number (Re) while deteriorating at a higher volume concentration. The lowest Nu was recorded for SWCNT/water in the current investigation. The Stanton number increases with a higher volume concentration and decreases with an increase of Re. Notably, the maximum value of 0.001801 is obtained for the SWCNT nanofluid. The outlet temperature decreases maximum for SWCNT/water with the increase of Re and volume concentration while the friction factor decreases with increasing Re and is independent of the type of nanofluids. Maximum thermo-hydraulic performance parameter of 1.48, 1.32 and 1.29 is achieved for SWCNT, Al2O3 and MWCNT, respectively.

In this work, pure and with 1, 3, 5, 10, and 15 wt% multi-walled carbon nanotube addition Bi2Sr2CaCu2O8+s glass-ceramic materials have been investigated in terms of thermal, structural, microstructural, electrical, and magnetic properties. Multi-walled carbon nanotubes with a purity of 96% were used to enhance electrical transport properties. Thermal properties have been examined using differential thermal analysis. According to the differential thermal analysis, the multi-walled carbon nanotube addition reduced the melting temperature and slightly increased the crystallization activation energy of the BiSrCaCuO material. X-ray analyses showed that all samples have tetragonal symmetry and did not change with addition, but a small change in the c-axis is observed. Scanning electron microscope analyses showed no significant morphological change. The effect of the additive on the resistivity measurements was found to be limited, and zero resistance temperature increased up to a level of 5 wt% addition and then decreased drastically for higher addition cases. The hole concentration of the samples was calculated, and it was found that there was a shift towards the over-doped region with the addition. For the transport critical current density measurements, the highest increase of about 30% was obtained for the sample with 5 wt% multi-walled carbon nanotube addition, but in high addition cases, significant losses were obtained. A similar situation occurred in magnetization versus magnetic field measurements, and the highest magnetization critical current density value obtained °was 4:1 X 106 A/cm² at 4.2 K in the 5 wt% multi-wall carbon nanotube added sample. [ABSTRACT FROM AUTHOR]

Aiming to improve the corrosion resistance of epoxy low-zinc coatings in marine environments, TiO 2 -MWCNTs nano-hybridized materials were prepared by sol-gel method in this study, and different contents of reinforcing phases were implanted as to improve the anticorrosive properties of epoxy low-zinc coatings. Characterization of the microscopic morphology, physical phase composition and chemical structure of the TiO 2 -MWCNTs materials demonstrated that the TiO 2 hybridization was successful and the loading of TiO 2 improved the dispersion of MWCNTs. To investigate the effect of the additive reinforcing phase on the mechanical and corrosion resistance of the coatings by characterizing the coating microscopic morphology, surface wettability, substrate adhesion, and impedance changes at different immersion times. The above results demonstrated that the epoxy composite coating had lower surface energy and 16 % larger surface contact angle compared with the pure epoxy low-zinc coating; the 0.4 wt% TiO 2 -MWCNTs/epoxy composite coating had the highest adhesion of 6.52 MPa. The electrochemical test results indicated that the TiO 2 -MWCNTs/epoxy low-zinc composite coating had the largest self-corrosion potential, the smallest self-corrosion current density of 4.538 μA/cm2, and the largest impedance of 242.3 KΩ/cm2. The addition of TiO 2 -MWCNTs reinforcing phase significantly extended the barrier protection time of the epoxy low zinc coating and maintained good corrosion resistance throughout the immersion cycle. [Display omitted] [ABSTRACT FROM AUTHOR]

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Recently, polymer composite based stretchable piezo‐electric energy harvesting device have attracted a great attention in composite industry. At laboratory scale, these piezo‐electric devices have ability to generate impressive voltage (~8 V) with high durability (>0.5 million cycles) depending upon nature of the material used in electrode and substrate. In this work, composites were prepared by mixing room temperature vulcanized silicone rubber (RTV‐SR) and nanofillers such as multi‐wall carbon nanotube (MWCNT), nano‐carbon black (nano‐CB), graphite nanoplatelets (GNP), in single or hybrid with molybdenum disulfide (MoS2). These fillers differentiate on basis of their structure ranging from 0‐dimensional (0‐D) to 3‐D. The effects of these structures on mechanical properties are demonstrated. Among them, MWCNT with 1‐D, tube shape morphology, high aspect ratio of 65 shows dominating mechanical properties even at 2 per hundred parts of rubber (phr) loading followed by nano‐CB, GNP at 8 phr and MoS2 at 2 phr. A synergistic effect in mechanical properties between hybrid fillers such as tensile strength and fracture strain was demonstrated. In the end, the composites were tested for piezo‐electric energy generation and durability cycles for the best candidate such as MWCNT was tested for up to 0.5 million cycles was demonstrated. [ABSTRACT FROM AUTHOR]

Electro-mechanical configurations can be piezo-electric transducers, triboelectric generators, electromagnetic induction, or hybrid systems. Our present study aims at developing energy generation through the piezoelectric principle. Gel-type soft SR with Shore A hardness below 30 was used as a versatile material for an elastomeric substrate. Also, multi-wall carbon nanotube (MWCNT), and diatomaceous earth (DE) were used as reinforcing fillers. This “gel-type” soft SR has crosslinking polymer networks with silicone encapsulated within its structure. Mechanical properties such as modulus or stretchability are of utmost importance for such devices based on “gel-type” soft. From the experiments, some of the mechanical aspect’s values are summarized. For example, the stretchability was 99% (control) and changes to 127% (3 phr, MWCNT), 76% (20 phr DE), and 103% (20 phr hybrid). From electro-mechanical tests, the output voltage was 0.21 mV (control) and changed to 0.26 mV (3 phr, MWCNT), 0.19 mV (20 phr DE), and 0.29 mV (20 phr hybrid). Moreover, from real-time biomechanical human motion tests in “gel-type” soft-based composites, a relationship among output voltage from machine to human motions was established. Overall, these configurations make them promising against traditional portable devices such as batteries for small power applications such as mobile phones.

The incorporation of carboxyl functionalized multi-walled carbon nanotube (MWCNT- COOH) into a polymethyl methacrylate (PMMA) has been investigated. The resultant tensile and flexural mechanical properties have been determined. In this paper, a novel synthesis process for a MWCNT-reinforced polymer nanocomposite is proposed. The proposed method significantly eliminates the most challenging issues of the nano-dispersed phase, including agglomeration and non-homogeneous mixing within a given matrix material, and also resolves the issues occurring in conventional mixing processes. The results of scanning electron microscopy support these claims. This 3D-mixing process is followed by an extrusion process, using a twin-screw extruder for pristine MWCNT, and a compression molding process for COOH-MWCNT, to prepare test specimens for experimentally determining the mechanical properties. The test specimens are fabricated using 0.1, 0.5, and 1.0 wt.% MWCNT, with a remaining PMMA phase. The testing is conducted according to ASTM D3039 and ASTM D7264 standards. Significant improvements of 25.41%, 35.85%, and 31.75% in tensile properties and 18.27%, 48%, and 33.33% in flexural properties for 0.1, 0.5, and 1.0 wt.% COOH-MWCNT in PMMA, respectively, compared to non-functionalized MWCNTs, were demonstrated. The highest strength was recorded for the nanocomposite with 0.5 wt.% f-MWCNT content, indicating the best doping effect at a lower concentration of f-MWCNT. The proposed CNT-PMMA nanocomposite may be found suitable for use as a scaffold material in the domain of bone tissue engineering research. This type of research possesses a high strength requirement, which may be fulfilled using MWCNT. Furthermore, this analysis also shows a significant amount of enhancement in flexural strength, which is clinically required for fabricating denture bases. [ABSTRACT FROM AUTHOR]

New technologies are constantly addressed in the scientific community for updating novel stretchable devices, such as flexible electronics, electronic packaging, and piezo-electric energy-harvesting devices. The device promoted in the present work was found to generate promising ~6V and durability of >0.4 million cycles. This stretchable device was based on rubber composites. These rubber composites were developed by solution mixing of room temperature silicone rubber (RTV-SR) and nanofiller, such as multi-wall carbon nanotube (MWCNT) and micron-sized copper particles and their hybrid. The hybrid composite consists of 50:50 of both fillers. The mechanical stretchability and compressive modulus of the composites were studied in detail. For example, the compressive modulus was 1.82 MPa (virgin) and increased at 3 per hundred parts of rubber (phr) to 3.75 MPa (MWCNT), 2.2 MPa (copper particles) and 2.75 MPa (hybrid). Similarly, the stretching ability for the composites used in fabricating devices was 148% (virgin) and changes at 3 phr to 144% (MWCNT), 230% (copper particles) and 199% (hybrid). Hence, the hybrid composite was found suitable with optimum stiffness and robust stretching ability to be useful for stretching electronic devices explored in this work. These improved properties were tested for a real-time stretchable device, such as a piezoelectric energy-harvesting device and their improved voltage output and durability were reported. In the end, a series of experiments conducted were summarized and a discussion on the best candidate with higher properties useful for prospective applications was reported. [ABSTRACT FROM AUTHOR]

This work highlights the recycling of waste carpet (Jute) to develop epoxy composites using a modified vacuum-assisted environment. Incorporating Multi-wall carbon nanotube (MWCNT) into the epoxy matrix in different weight percentages improves the physio-mechanical properties. The MWCNT was supplemented at 0.25, 0.5, 0.75, and 1 wt% to investigate the mechanical aspects of composite samples. The nanofiller (MWCNT) dispersion in the epoxy matrix was simulated using X-ray diffraction (XRD) and Energy Dispersive X-Ray Analysis (EDX). The results were compared to the neat (pristine) sample to study the influence of nano-supplement. The Tensile, Flexural, and Impact tests were the selected experiments to assess the material characteristics. The findings show the feasibility of the developed samples for lightweight structural applications such as toy items, wall tiles, roof tiles, sound insulation, and roadside barriers. It could be endorsed as a feasible way to handle the waste issues generated by the carpet and textile sources. [ABSTRACT FROM AUTHOR]

The article intends to obtain an environment friendly, low-cost natural fiber (Agave Cantala Fiber) and Multi-walled carbon nanotube (MWCNT) composite by the experimental design approach. More specifically, study is associated with multi-response modelling and optimization of a novel composite material for cleaner manufacturing. The Mixture Design technique is adopted to ensure the mixture components' multi-response optimization, namely, MWCNT, Cantala fibers, and Epoxy resin. The tensile, flexural, and impact strength of the novel composite material are considered for optimization. The experiments are planned as per the mixture design, and the data is collected on all these responses. The Cox Response Trace plot, Pareto Chart for Standardized Effects, Overlaid Contour plot, and Response Optimizer plot are effectively used to develop predictive models and to identify an optimum combination of the mixture for all the responses. The findings will assist in developing an optimal combination of component mixtures and a predictive model for composite material through the structured and robust statistical methodology. This material will assist in cleaner and greener manufacturing of composite materials, while the approach adopted will help researchers as a template for robust composite material development. [ABSTRACT FROM AUTHOR]

In industrial-thermal applications, pulsating flow along with carbon-based nanofluids is a well adopted active method, although not in plate heat exchangers (PHEs). The performance of a PHE with carbon-based nanofluids was experimentally evaluated by superimposing pulsating flow along with steady-state flow. The results demonstrated that the use of GNP -water, hybrid GNP/MWCNT -water, and MWCNT -water nanofluids with volume fractions ranging from 0.01% to 0.1% in a steady-state flow led to improved average heat-transfer rates of 1.34, 1.27, and 1.25, respectively. Furthermore, implementation of pulsating flow enhanced the average heat-transfer rate, in comparison to that of the steady-state flow in the same nanofluids, in the range of 10.9%–28.2%, 9%–25.4%, and 7.1%–14.8%, respectively. Pulsating flow in nanofluids improved heat-transfer rate more than it did in pure water owing to the enhancement of the Brownian motion of the suspended carbon-based nanoparticles. In the considered volume fractions from 0.01% to 0.1%, the pulsating flow condition increased the pressure drop by a factor of 1.48, 1.49, and 1.62 for the MWCNT -water, hybrid GNP/MWCNT -water, and GNP -water nanofluids, respectively, in comparison to pure water. The experimental results indicated that the pulsating flow had a more profound influence on the improvement of heat-transfer rate and pressure drop in the case of GNP -based nanofluid than in the others. This could be attributed to the unique platelet shape of the GNP nanoparticles and consequently the higher Brownian motion. The improvement in the heat-transfer rate, obtained through implementation of the pulsating flow condition, outweighed the cost of increase in pressure drop in all the cases. Among the nanofluids considered, the hybrid GNP/MWCNT -water nanofluid exhibited the best overall performance of 1.2. [ABSTRACT FROM AUTHOR]

In this study, the effects of drilling parameters on the thrust force in the drilling process of glass fiber reinforced polymer composites were investigated experimentally and statistically. Multiwalled carbon nanotube wt. % content, cutting speed and feed rate were considered as independent variables, the thrust force was considered as dependent variable. Experiments are conducted based on Box–Behnken design. A mathematical model was developed to predict thrust force using response surface methodology. Desirability Function Analysis was used to determine optimum drilling parameters. The influence of process parameters on the thrust force has been evaluated using analysis of variance. The results indicate that the feed rate is the most significant design factor influencing the thrust force. The values predicted from the model and experimental values were found to be very close to each other.

Twisted laminar superconducting composite structures based on multi-wall carbon nanotube (MWCNT) yarns were crafted by integrating magnesium and boron homogeneous mixture into the carbon nanotube (CNT) aerogel sheets. After the ignition of the Mg–B–MWCNT system, under the controlled argon environment, the high exothermic reaction between magnesium (Mg) and boron (B) with stoichiometric ratio produced the MgB2@MWCNT superconducting composite yarns. The process was conducted under the controlled argon environment and uniform heating rate in the differential scanning calorimetry and thermogravimetric analyzer. The XRD analysis confirmed that the produced composite yarns contain nano and microscale inclusions of superconducting phase of MgB2. The mechanical properties of the composite twisted and coiled yarns at room temperature were characterized. The tensile strength up to 200 MPa and Young’s modulus of 1.27 GPa proved that MgB2@MWCNT composite is much stiffer than single component MgB2 wires. The superconductive critical temperature of Tc ~38 K was determined by measuring temperature-dependent magnetization curves. The critical current density, Jc of superconducting component of composite yarns was obtained at different temperatures below Tc by using magnetic hysteresis measurement. The highest value of Jc = 3.39 × 107 A cm−2 was recorded at 5 K. [ABSTRACT FROM AUTHOR]

A novel sulfonated multi-wall carbon nanotubes (s-MWCNTs) filler is synthesized by ring-opening reaction. And then, a series of branched sulfonated polyimide (bSPI)/s-MWCNTs composite membranes are also prepared for application in vanadium redox flow batteries (VRFBs). The optimized bSPI/s-MWCNTs-2% composite membrane has lower vanadium ion permeability (2.01 × 10−7 cm2 min−1) and higher proton selectivity (1.06 × 105 S min cm−3) compared to those of commercial Nafion 212 membrane. Moreover, the VRFB with bSPI/s-MWCNTs-2% composite membrane exhibits higher coulombic efficiencies (CE s: 96.0–98.2%) and energy efficiencies (EE s: 79.7–69.5%) than that with Nafion 212 membrane (CE s: 86.5–92.5% and EE s: 78.5–67.6%) at 80–160 mA cm−2. The VRFB with bSPI/s-MWCNTs-2% composite membrane has stable battery performance over 400 cycles at 100 mA cm−2, whose EE value is in the top level among previously reported SPI-based composite membranes. The results show that the bSPI/s-MWCNTs-2% composite membrane has a great prospect in VRFB application. [Display omitted] • The s-MWCNTs filler is synthesized by a grafting reaction. • A series of bSPI/s-MWCNTs composite membranes are prepared. • The bSPI/s-MWCNTs-2% composite membrane has excellent comprehensive performance. • bSPI/s-MWCNTs-2% composite membrane shows high VRFB efficiencies and durability. [ABSTRACT FROM AUTHOR]

The in‐mold coating (IMC) process nowadays is well accepted by the sheet molding compound industry. The currently used IMC contains 2.8 wt% carbon black (CB) to provide enough electrical conductivity for maximum paint transfer efficiency (PTE) for electrostatic painting. Due to its relatively large viscosity, this formulation makes use of more than one injection gate for coating some large parts necessary. Our previous research investigated the possibility to replace the CB with higher conductivity carbon‐based nanoparticles, namely carbon nanofibers (CNFs), multi‐wall carbon nanotubes (MWCNTs), industrial graphene (grapheneblack [G]), and single‐wall carbon nanotubes (SWCNTs) and found that the IMC with 11.3 wt% G has the best processability among all IMC formulations. To improve this formulation, herein, we study the use of a second reinforcement in combination with G, i.e., CB, CNF, and MWCNT. Results from this study suggest that most G/CB‐reinforced IMC formulations have a better performance than the G‐reinforced IMC formulations, and IMC with 1 wt% CB and 6 wt% G is the best among all G/CB‐reinforced IMC formulations. To be specific, the new formulation allows parts to be painted to have a 300% increase in size when compared with the standard IMC. [ABSTRACT FROM AUTHOR]

In this study, the effect of multi-wall carbon nanotube (MWCNT) on machining damages and material removal mechanisms in electro-discharge machining (EDM) of carbon fiber reinforced epoxy resin (CFRE) was evaluated. Field-emission scanning electron microscopy (FE-SEM) was used to investigate the machined surface morphology and elemental analysis. The effect of MWCNT content, pulse current, and pulse-on time was investigated on machining damages such as delamination, hole taper, and machining characteristics containing tool wear and material removal rate. The experimental tests were conducted according to the full-factorial design of the experiment. The FE-SEM images showed that decomposition and vaporization are dominant removal mechanisms. Elemental analysis clarified that burning is one of the removal mechanisms in EDM of CFRE. Based on the elemental analysis, the burning mechanism is reduced by incorporation of the MWCNT into epoxy resin. The results of EDM machining tests showed that as compared to CFRE, introducing MWCNT into epoxy resin in epoxy/carbon fiber/MWCNT hybrid composites improves material removal rate and decreases delamination factor and taper hole. [ABSTRACT FROM AUTHOR]

In this study, commercial phosphorus powders were first subjected to mechanical ball-milling at varying times and reinforced with graphene oxide and multiwall carbon nanotubes to improve their electrochemical performances. All these processes were carried out by ball milling method to provide mechanical alloying of phosphorus. Subsequently, the crystallinity of the samples was analyzed by X-ray diffraction method, while the morphology of the samples was examined by field emission scanning electron microscopy. The main obstacles that inhibit the reversibility and the cyclic stability of red phosphorus are low electronic conductivity and huge volumetric expansion. Reinforcing amorphized phosphorous with multi-walled carbon nanotube and graphene oxide composites has presented similar initial capacity of 2100 mAh g−1. In addition, reversible capacity of multi-walled carbon nanotube and graphene oxide reinforced samples presented 370 mAh g−1 and 507 mAh g−1 after 250 cycles, respectively. Our results have shown that graphene oxide reinforced composites could be an alternative electrode material for sodium ion battery applications. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, multi-wall carbon nanotubes (MWCNT) are added (0–0.5 wt%) into a cement matrix to improve the flexural performance of the resulting nanocomposites. Under static testing, the compressive and flexural strengths were found to increase with MWCNT content with an optimum content of 0.2% and 0.1%, respectively, before decreasing because of dispersion problems (agglomeration). But it was observed that increasing the mixing time and adding silica fume improved the MWCNT dispersion. Under fatigue testing, similar trends were obtained with respect to MWCNT content as the maximum fatigue life was observed at 0.2%. A comparison between nano-silica and MWCNT reinforced concrete is also made showing that MWCNT provides better improvement at lower content. The MWCNT reinforced cement-based composite results were well fitted using linear regressions. Finally, a morphological analysis via scanning electron microscopy (SEM) was performed to explain the results based on the micro-mechanical mechanism of MWCNT reinforced composites. [ABSTRACT FROM AUTHOR]

• ZrB 2 composites were fabricated by SPS and reinforced with in-situ synthesized ZrC. • Metallic Zr and graphite or CNT as carbon source were used for synthesis of ZrC. • Graphite did not result in detectable ZrC in the final microstructure. • CNT promoted the in-situ synthesizability of zirconium carbide. • Mechanisms of ZrC formation were discussed and illustrated schematically. ZrB 2 -based composites were consolidated through reactive spark plasma sintering of the powder mixtures containing relatively 5 vol.% of metallic Zr particles, and graphite flakes (GF) or carbon nanotubes (CNT) as the carbon source, with the aim of ZrC in-situ synthesis in ZrB 2 matrix. Microstructural and phase analyses indicated that GFs cannot result in detectable ZrC in the final microstructure. Contrarily, it was found that CNTs promote the in-situ synthesizability of zirconium carbide in the composite system. However, the sample containing graphite flakes presented better densification outcomes. The mechanism of ZrC formation in the composites, based on the carbon source, was finally discussed and illustrated. [ABSTRACT FROM AUTHOR]

In this study, iron manganese composite oxide (FeMnOx) were integrated with multi-walled carbon nanotube (MWCNTs) to synthesize an effective adsorbent for acid orange (AO) and basic violet (BV), two widely used organic dyestuffs belonging to anionic and cationic, respectively. Among all the composites evaluated, the FeMnOx-MWCNTs with Fe–Mn ratios of 1:1 and load ratio of 45% achieved superior adsorption capacity than others, and was selected as the best adsorbent. The Characterization data indicated that the physicochemical properties and structural characteristics of FeMnOx-MWCNTs have changed obviously after modification, with larger specific surface area and richer groups. The maximum adsorption capacity of AO (403.23 mg/g) and BV (165.29 mg/g) could be attained under optimal conditions: 300 min, 0.05 g adsorbent dosage, 100 mg/L dyes and pH 2.0 (for AO) or pH 10.0 (for BV). Moreover, the adsorption kinetics of the two dyes were both well fitted the pseudo-second-order kinetics model, and the adsorption isotherms agreed well with the Freundlich model for AO while Langmuir model for BV. Moreover, the FeMnOx-MWCNTs with optimal FeMnOx content showed relatively higher final adsorption amount and faster adsorption rate, thus better fitting with the kinetics. A mechanism was proposed that physical adsorption is the dominator during the process. The results indicated that the introduction of FeMnOx into the MWCNTs significantly enhanced the dye removal efficiency, providing a promising method for the improvement of carbon nanometer adsorbents. The selected graph can not only express the synthetic methods of FeMnOx-MWCNTs by chemical coprecipitation, but also presented the adsorption process and mechanism of AO and BV, which showed the purposes of this work simultaneously. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the brain toxicity following the respiratory contact with multi-wall carbon nanotubes (MWCNTs) in male Wistar rats. Rats were exposed to 5 mg/m3 MWCNT aerosol in different sizes and purities for 5 h/day, 5 days/week for 2 weeks in a whole-body exposure chamber. After 2-week exposure, mitochondrial isolation was performed from different parts of rat brain (hippocampus, frontal cortex, and cerebellum) and parameters of mitochondrial toxicity including mitochondrial succinate dehydrogenase (SDH) activity, generation of reactive oxygen species (ROS), mitochondrial membrane potential (MMP) collapse, mitochondrial swelling, and cytochrome c release, ATP level, mitochondrial GSH, and lipid peroxidation were evaluated. Our results demonstrated that MWCNTs with different characteristics, in size and purity, significantly (P < 0.05) decreased SDH activity, GSH, and ATP level, and increased mitochondrial ROS production, lipid peroxidation, mitochondrial swelling, MMP collapse, and cytochrome c release in the brain mitochondria. In conclusion, we suggested that MWCNTs with different characteristics, in size and purity, induce damage in varying degrees on the mitochondrial respiratory chain and increase mitochondrial ROS formation in different parts of rat brain (hippocampus, frontal cortex, and cerebellum). [ABSTRACT FROM AUTHOR]

Homogeneous nanopores were constructed in poly(oxymethylene)/multi-wall carbon nanotube (POM/MWCNT) nanocomposites by poly(l -lactide) (PLLA) assisting to improve microwave shielding property through the multiple refection and scattering on the walls of the nanopores. • Nanopores were constructed in the POM/MWCNT composites by PLLA assisting. • High microwave shielding was achieved in the POM/MWCNT composites with nanopores. • Multiple reflections and scattering of microwaves happened on walls of nanopores. • These nanoporous composites maintained high compression and tensile properties. Lightweight and high-performance conductive polymer composites (CPCs) have attracted much attention for electromagnetic interference (EMI) shielding. Herein, the porous structure was constructed in poly(oxymethylene)/multi-wall carbon nanotube (POM/MWCNT) nanocomposites via assisting by poly(l -lactide) (PLLA). First, the POM/PLLA/MWCNT (S-PMLNT) nanocomposites were obtained by melt mixing and compression molding. Second, the nanoporous POM/MWCNT (P-PMNT) nanocomposites were fabricated by selectively dissolving PLLA, solvent exchanging and freeze-drying. Because of well miscible between PLLA and POM, the homogeneous nanopores could be successfully fabricated in the P-PMNT composites by removing the PLLA phase. The multiple reflections and scattering of microwaves happened on the walls of these nanopores, which endowed the P-PMNT nanocomposites having higher EMI shielding effectiveness (SE) in comparison of the S-PMLNT nanocomposites, although the P-PMNT nanocomposites exhibited the lower electrical conductivity. For example, the S-PMLNT samples with 10 wt% MWCNTs showed an EMI SE of 48.1 dB and an electrical conductivity of 333 S/m, which changed to 58.6 dB in EMI SE and 125 S/m in electrical conductivity after removing PLLA phase. Furthermore, the P-PMNT10 nanocomposites had outstanding the EMI normal SE (SE/d) of 29.3 dB mm−1 and the EMI specific shielding effectiveness (SSE/d) of 344.4 dB cm2 g−1 because of their low density. In addition, the P-PMNT nanocomposites maintained high compression and tensile strength simultaneously. [ABSTRACT FROM AUTHOR]

Compared to other alloys of Aluminium, AA5083 alloy is one of the most promising material which is used in corrosive and cryogenic environment. The effect of the purity and weight percentage of Multi-wall Carbon Nanotube (MWCNT) added to the Aluminium alloy is the widely focused research area in the field of Cryogenics in recent years. In this present work, MWCNT having more than 98% purity, 5–20 nm mean diameter (D) and 1–10 μm average length (L) was used with different compositions like 1, 1.25, 1.5 and 1.75 by weight % to improve the corrosion behaviour of the Aluminium Nano Metal Matrix Composite (ANMMC). The results show Aluminium alloy AA5083 reinforced with MWCNT exhibit nominal changes in density than pure AA5083 and the uniform immersion corrosion tests (ASTM-G31) of the same composite in 90 ml of HCl shows increase in corrosion resistance as compared to AA5083 alloy.

One way to reduce sensitivity and also adding special properties to explosives is a coating that depends on either the coating agent type or the usage process. In this work, an insensitive nanocomposite of PETN was prepared with multi‐wall carbon nanotube (MWCNT) and Triton X‐114 (TX114) by the solvent/nonsolvent method. Taguchi experimental design (orthogonal array, L9) using impact sensitivity (H50) investigation was applied to the process optimization. The variable effects of MWCNT mass fraction, solvent (acetone) flow rate, surfactant type and surfactant concentration were evaluated and then the results were quantified by the analysis of Variance (ANOVA). ANOVA data predicted the best H50 was 84.03±3.43 cm that was obtained for the optimum conditions of 5.0 wt% MWCNT, 1 mL min−1 flow rate, TX114 as surfactant with a concentration of 1.0×10−3 mol Lit−1. Practical results of H50 were obtained 84.0±0.5 cm that were in agreement with the predicted H50. Finally, thermal analysis and vacuum stability test were applied to the synthesized nanocomposite and the obtained results indicate MWCNT and TX114 are thermal adaptable and chemically compatible with PETN. [ABSTRACT FROM AUTHOR]

Nanoparticles of doped strontium hexaferrite (SrZn0.1Co0.1Sn0.2Fe11.6O19) were synthesized by the sol–gel auto-combustion method as a salient magnetic photocatalyst. For enhancing photocatalytic properties, a nanocomposite of the SrZn0.1Co0.1Sn0.2Fe11.6O19/multiwall carbon nanotube (MWCNT) and SrZn0.1Co0.1Sn0.2Fe11.6O19/polyaniline (PANI) was prepared. Fourier transform infrared spectra confirmed the formation of tetrahedral and octahedral vibrating modes of the Fe–O on the hexaferrite structure. In x-ray diffraction (XRD) patterns of SrZn0.1Co0.1Sn0.2Fe11.6O19/MWCNT, both the MWCNT's peak at 2θ = 26.4° and hexaferrite pattern confirmed the formation of the nanocomposite. XRD analysis of SrZn0.1Co0.1Sn0.2Fe11.6O19/PANI nanocomposite represented the amorphous peak belonging to PANI. Field emission scanning electron microscopy pictures of SrZn0.1Co0.1Sn0.2Fe11.6O19/MWCNT showed nanoparticles of hexaferrite on the surface of the MWCNT's nanofibers. In the SrZn0.1Co0.1Sn0.2Fe11.6O19/PANI nanocomposite, the spherical PANI encompassed the hexaferrite structure. Vibrating sample magnetometer hysteresis loops revealed that the SrZn0.1Co0.1Sn0.2Fe11.6O19 can be classified as a soft magnetic material. By adding non-magnetic particles of MWCNTs and PANI, the saturation magnetizations of all nanocomposites decreased. Photocatalytic studies showed that by adding PANI as a conducting polymer and MWCNTs with a high surface area, the mechanism of dye degradation was accelerated in comparison to the pure SrZn0.1Co0.1Sn0.2Fe11.6O19 nanoparticles. The kinetics, rate and mechanism of photodegradation were studied for all samples. By fabricating PANI nanocomposites, the remarkable transfer of charge carriers facilitated the methylene blue decomposing process. On the other hand, due to the high surface area of MWCNTs and decreasing the electron–hole accumulation, the degradation process was enhanced. [ABSTRACT FROM AUTHOR]

Abstract Carbon-based nanomaterials have been attracted to the worldwide because of remarkable thermal and mechanical properties. In this study, one-dimensional multi-wall carbon nanotube (MWCNT), two-dimensional graphene nanoplatelets (GNPs) and zero-dimensional fullerene (C60) reinforced pure aluminum matrix composites were fabricated to develop mechanical properties of pure aluminum. Solution-based semi powder metallurgy technique and hot extrusion process were used for fabrication. Microstructure and mechanical properties were investigated. Hardness and tensile tests were performed to determine the mechanical performance. Results clearly show that tensile and hardness properties of pure aluminum was significantly improved even low amount (0.25 wt %) of nano carbon addition. C60 reinforced composite exhibits highest yield and tensile strength and it has best hardness value among the produced samples. Highlights • Composites were fabricated via semi powder metallurgy technique successfully. • Hardness was improved with the addition of carbonaceous reinforcements. • Weight loss of pure aluminum decreased with the addition of MWCNT, GNPs and C60 at melting points. • Homogenously distribution of carbon was observed especially for C60 reinforced composite. • C60 reinforced aluminum matrix composite exhibited best mechanical performance. [ABSTRACT FROM AUTHOR]

Electrical Discharge Machining (EDM) process with copper tool electrode is used to investigate the machining characteristics of AISI D2 tool steel material. The multi-wall carbon nanotube is mixed with dielectric fluids and its end characteristics like surface roughness, fractal dimension and metal removal rate (MRR) are analysed. In this EDM process, regression model is developed to predict surface roughness. The collection of experimental data is by using L9 Orthogonal Array. This study investigates the optimization of EDM machining parameters for AISI D2 Tool steel using Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) method. Analysis of variance (ANOVA) and F-test are used to check the validity of the regression model and to determine the significant parameter affecting the surface roughness. Atomic Force Microscope (AFM) is used to capture the machined image at micro size and using spectroscopy software the surface roughness and fractal dimensions are analysed. Later, the parameters are optimized using MINITAB 15 software, and regression equation is compared with the actual measurements of machining process parameters. The developed mathematical model is further coupled with Genetic Algorithm (GA) to determine the optimum conditions leading to the minimum surface roughness value of the workpiece.

The multi-wall carbon nanotube (MWCNT) reinforced alumina (Al _2 O _3 ) matrix composites were fabricated by spray drying and vacuum hot-pressing sintering. The mechanical properties of the composites with different mass fractions of MWCNT were studied. The flexural strength and fracture toughness of the composite were 498.3 MPa and 5.69 MPa·m ^1/2 , respectively, which were about 55.3% and 84.7% higher than that of pure Al _2 O _3 . With the increase in the content of MWCNT, the Vickers hardness and relative density of the composite decreased gradually. The correlation between the microstructure and the mechanical properties of the composite was analyzed.

A sensor, based on multi-wall carbon nanotubes modified glassy carbon electrode (MWCNT/GCE), was developed for determination of fenitrothion. Determining the surface area of MWCNT/GCE showed that this surface is three times more active than that of a glassy carbon electrode. The experimental parameters, such as the amount of MWCNTs, pH of the fenitrothion solution, preconcentration potential and preconcentration time were optimized. Under these conditions, reduction current showed a linear relationship with the concentration of fenitrothion in a range of 0.01-5.0 mM, with a detection limit of 6.4 nM. The modified electrode also exhibited good stability and reproducibility. The effects of possible interferents were studied and found to be negligible, indicative of high selectivity of the electrode. This sensor was also successfully employed for determination of fenitrothion in soil and Teff samples with recovery values in the range of 88.0-93.3% and 86.7-91.4%, respectively.