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The purpose of this study is to fabricate an ultraviolet (UV) metal-semiconductor-metal (MSM) photodetector based on zinc oxide nanorods (ZnO NRs) grown on seeded silicon (Si) substrate that was prepared by a low-cost method (drop-casting technique).

The drop-casting method was used for the seed layer deposition, the hydrothermal method was used for the growth of ZnO NRs and subsequent fabrication of UV MSM photodetector was done using the direct current sputtering technique. The performance of the fabricated MSM devices was investigated by current–voltage (I–V) measurements. The photodetection mechanism of the fabricated device was discussed.

Semi-vertically high-density ZnO (NRs) were effectively produced with a preferential orientation along the (002) direction, and increased crystallinity is confirmed by X-ray diffraction analysis. Photoluminescence results show a high UV region. The fabricated MSM UV photodetector showed that the ZnO (NRs) MSM device has great stability over time, high photocurrent, good sensitivity and high responsivity under 365 nm wavelength illumination and 0 V, 1 V, 2 V and 3 V applied bias. The responsivity and sensitivity for the fabricated ZnO NRs UV photodetector are 0.015 A W-1, 0.383 A W-1, 1.290 A W-1 and 1.982 A W-1 and 15,030, 42.639, 100.173 and 334.029, respectively, under UV light (365 nm) illumination at (0 V, 1 V, 2 V and 3 V).

This paper uses the drop-casting technique and the hydrothermal method as simple and low-cost methods to fabricate and improve the ZnO NRs photodetector.

The paper aims to study the effects of humidity on the electrical properties of copper phthalocyanine (CuPc) thin films deposited at different gravity conditions.

Surface-type samples were fabricated on glass substrates with preliminary-deposited copper electrodes. The CuPc solution was prepared in benzene. The thin films of CuPc were deposited on these substrates at diverse gravity conditions by drop-casting and centrifugation at 1 × g and 70 × g, respectively. Impedance and capacitance of the fabricated devices were measured against the different relative humidity ranging from 32 to 98 per cent.

The impedance and the capacitance of the CuPc film were found to be dependent on the ambient humidity levels (32-98 per cent) and the gravity conditions (1 × g and 70 × g) opted during the fabrication process.

The centrifugation technique can potentially be used in the instrumentation industry for the fabrication of humidity sensors.

The results of the investigations can potentially be used in the instrumentation and optoelectronics industry for the fabrication of humidity sensors.

CuPc films were deposited from a solution in benzene using drop-casting and centrifugation. The electrical properties of the films were found to be dependent on film fabrication conditions and ambient humidity levels. Growth-dependent electrical properties of the CuPc films can be explained by considering their structure.

Ti6Al4V is a commonly used titanium alloy with several applications in aerospace industry due to its excellent strength to weight ratio. But due to low thermal conductivity, it is categorized as “difficult to machine.” Though machinability can be improved with cutting fluids, it is not preferred due to associated problems. This study aims at eliminating the use of cutting fluid and finding an alternate solution to dry machining of Ti6Al4V. AlTiN coated tools provide good heat and oxidation resistance but have low lubricity. In the present work, graphene, which is known for lubricating properties, is added to the tools using five different methods (tool condition) to form graphene self-lubricated cutting tools.

Graphene-based self-lubricating tools are prepared by using five methods: dip coating (10 dips and 30 dips); drop casting; and filling of micro/macroholes. Performance of these tools is evaluated in terms of cutting forces, surface roughness and tool wear by machining Ti6Al4V and comparing with conventional coated cutting tool.

Self-lubricating tool with micro holes filled with graphene outperformed other tools and showed maximum decrease of 33.42% in resultant cutting forces, 35% in surface roughness (Ra) and 30% in flank wear compared to conventional cutting tool.

Analysis of variance for all forces show that tool condition and machining time have significant influence on all components of cutting forces and resultant cutting forces.

Ascorbic acid (AA) is an essential vitamin for human health. Therefore, fast and cost-effective detecting of AA is essential, whether in human or food samples. The purpose of this paper is to develop an electrochemical nanosensor for AA detection.

The proposed nanosensor was developed by printing carbon nanoparticles ink and silver nanoparticles ink on a polydimethylsiloxane (PDMS) substrate. The surface of the PDMS substrate was first treated by corona plasma. Then, the nanomaterials printer was used to deposit both inks on the substrate. The working electrode surface was modified by drop-casting of carbon nanotubes. Morphological evaluation was applied using scanning electron microscopy and cyclic voltammetry. Also, a potentiostat was used to detect AA by differential pulse voltammetry.

It has been shown that the developed nanosensor linearly worked at a range of (0–5 mM), with a limit of detection lower than 0.8 mM and a relative standard deviation of 6.6%.

The developed nanosensor is characterized by a simple and cost-effective sensing tool for AA. In particular, the nanomaterials enhanced the nanosensor’s sensitivity due to the high catalytic activity.

This study aims to present an efficient and reliable graphene nanoplatelets (GNPs)-based temperature sensor.

A high-quality dispersion of GNPs was dropped by casting method on platinum electrodes deposited on a polyethylene terephthalate (PET) substrate. The GNPs were characterized by scanning electron microscope, Raman spectroscopy and X-ray diffraction spectra to ensure its purity and quality. The temperature sensing behavior of the fabricated sensor was examined by subjecting it to different temperatures, range from room temperature (RT) to 150 °C.

Excellent resistance linearity with temperature change was achieved. Temperature coefficient of resistance of the fabricated sensor was calculated as 1.4 × 10^–3°C. The sensor also showed excellent repeatability and stability for the measured temperature range. Good response and recovery times were evaluated at all the measured temperatures. With measuring the sensor response, the ambient temperature can be determined.

The present work presents a new simply and low cost fabricated temperature sensor based on GNPs working at a wide temperature range.

Design, fabricate and evaluate all-solid-state wearable sensor systems that can monitor ion concentrations in human sweat to provide real time health analysis and disease diagnosis capabilities.

A human health monitoring system includes disposable customized flexible electrode array and a compact signal transmission-processing electronic unit.

Patterned rGO (reduced-graphene oxide) layers can replace traditional metal electrodes for the fabrication of free-standing all solid film sensors to provide improved flexibility, sensitivity, selectivity, and stability in ion concentration monitoring. Electrochemical measurements show the open circuit potential of current selective electrodes exhibit near Nernst responses versus Na+ and K+ ion concentration in sweat. These signals show great stability during a typical measurement period of 3 weeks. Sensor performances evaluated through real time measurements on human subjects show strong correlations between subject activity and sweating levels, confirming high degree of robustness, sensitivity, reliability and practicality of current sensor systems.

In improving flexibility, stability and interfacial coherency of chemical sensor arrays, rGO films have been the developed as a high-performance alternative to conventional electrode with significant cost and processing complexity reduction. rGO supported solid state electrode arrays have been found to have linear potential response versus ion concentration, suitable for electrochemical sensing applications. Current sweat sensor system has a high degree of integration, including electrode arrays, signal processing circuits, and data visualization interfaces.

The purpose of this paper is to fabricate and investigate sensing properties of a novel, flexible resistive tensile load cells based on multi-walled carbon nano-tubes (MWCNTs)/rubber composites. The use of carbon nanotubes makes it very attractive for being used as sensors.

On thin rubber substrate, MWCNTs powder was deposited and pressed at elevated temperature. Two types of samples were prepared: first sample was made by depositing MWCNTs suspension in water on the substrate, then the sample was dried at room temperature; the second sample was prepared by applying dry MWCNTs powder directly on the substrate.

The resistances of the cells made from wet MWCNT powder are much lower than those made with dry powder. It was found that the fabricated load cells were highly sensitive to the force and showed good repeatability. The resistance of the flexible resistive tensile MWCNTs/rubber composite load cells increased 1.37 times, on average, with the increasing force (up to 0.045 N). The sensitivity of the cells was equal to 142 N-1.

The device fabrication method used here provides a simple, less expensive and effective approach for preparing resistive tensile load cells.

A novel, flexible resistive tensile load cells using MWCNTs/rubber composites have been successfully fabricated and investigated. MWCNTs, in dry and wet form, have been deposited on thin rubber substrates by adopting a very simple and inexpensive technique.

The aim of this review is to present together the studies on textile-based moisture sensors developed using innovative technologies in recent years.

The integration levels of the sensors studied with the textile materials are changing. Some research teams have used a combination of printing and textile technologies to produce sensors, while a group of researchers have used traditional technologies such as weaving and embroidery. Others have taken advantage of new technologies such as electro-spinning, polymerization and other techniques. In this way, they tried to combine the good working efficiency of the sensors and the flexibility of the textile. All these approaches are presented in this article.

The presentation of the latest technologies used to develop textile sensors together will give researchers an idea about new studies that can be done on highly sensitive and efficient textile-based moisture sensor systems.

In this paper humidity sensors have been explained in terms of measuring principle as capacitive and resistive. Then, studies conducted in the last 20 years on the textile-based humidity sensors have been presented in detail. This is a comprehensive review study that presents the latest developments together in this area for researchers.

The purpose of the present study is to use an amino-functional polysiloxane for the surface modification of red iron oxide (Fe₂O₃) pigment particles for their improved dispersion stability and hydrophobicity and to study the chemical interactions of polysiloxanes with the particle surface.

Surface-treated red Fe₂O₃ pigment particles were prepared by treatment of the particles with different quantities of the (aminopropylmethylsiloxane)-dimethylsiloxane copolymer in concentrated suspensions in water. The samples were analysed with different instrumental and spectroscopic techniques to study the interaction of the polysiloxane with the particle surface and the effect of the surface treatment of the particles on their dispersion stability and hydrophobicity.

Chemisorption of the amino-polysiloxane onto the surface of Fe₂O₃ particles resulted in stable layers which turned out to be helpful in improving greatly the dispersion stability of the particles as shown by the Static Light Scattering and Dynamic Light Scattering results. Formation of a polysiloxane coating onto the surface of the pigment particles was confirmed by studying the interactions of the polymer molecules with Fe₂O₃ surfaces by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy techniques.

The surface-treated red Fe₂O₃ particles with improved dispersion stability can be important components of various formulations in applications such as the colouring of the cement or inorganic pigment-based paint formulations.

The study provides mechanistic insights about the interactions of amino-polysiloxane with the red Fe₂O₃ particles. The process of surface modification of red Fe₂O₃ particles with the amino-functional polysiloxane showed increased hydrophobicity and dispersion stability which is an important requirement of the pigment-based formulations in real applications.

The purpose of this paper is to study the effect of thermal treatment on the corrosion protection of steel by using poly(3-hexylthiophene) (P3HT) and P3HT/PS(polystyrene) or P3HT/PMMA(polymethyl methacrylate) blends coatings in sulfuric acid solution.

The polymer coatings were thermally treated at two different temperatures (100 and 200°C, respectively) and were compared with the polymer coatings dried at room temperature in their application as protective coatings against corrosion of A36 steel. The corrosion resistance of polymer coatings-covered steel substrates was evaluated by using potentiodynamic polarization curves and linear polarization resistance.

At 25 and 100°C, polymer coatings showed a better protection of the A36 steel, and the corrosion rate diminished in three orders of magnitude with regard to the bare steel. Morphological study showed that the increased temperature benefited the integration of the two polymeric phases; however; the temperature of 200°C affected the film quality, generated cracks and holes, which affected the barrier properties of the coatings.

The research involved the synthesis and physicochemical characterization of the polymeric coatings (P3HT, PS/P3HT y PMMA/P3HT), as well as their application as coatings in the steel to prevent corrosion. The effect of thermal treatment of the protective coatings on steel corrosion was studied.

This paper aims to contribute to reducing the problem of metal corrosion through the use of polymer coatings.

Today, majority of metal surfaces are subject under the protection to prevent a very common phenomenon, that is corrosion. Corrosion is the result of chemical reactions that occur between a metal or a metal alloy and its environment. Corrosion creates a degradation of the material that has an impact on some economic, environmental and even social aspects, here the great importance of its protection.

It is shown in this study that the P3HT coating provides better corrosion protection of the A36 steel than the PS and PMMA coatings. However, mixtures of P3HT with PMMA and PS protected the steel from corrosion by two and three orders of magnitude similar to the simple P3HT coating. Polymer blends improved adhesion to the substrate and mechanical property of the coating, and in addition, the polymer blends made cheaper coating.