Effects of hard chrome and MoN-coated stainless steel on wear behaviour and tool life model under two-body abrasion wear testing

The objectives of this study were to investigate the effect of the electroplated hard chrome (HC) and the MoNcoated AISI 316 stainless steel coatings on weight loss under two-body abrasion wear testing and to predict the tool life of both materials used as a fishing net-weaving machine component, namely the hook. Both materials were used to carry out the wear experiments under two-body abrasion behavior. These specimens were wear tested with the in-house wear testing apparatus base on ASTM: G133-05 standard. The Taylor’s equation was used to formulate the tool life model whereas the Monte Carlo simulation was used to predict the tool life of the machine part. The results showed that the MoN-HC exhibited higher wear resistance than that of the HC

Microfluidic-based Split-Ring-Resonator Sensor for Real-time and Label-free Biosensing

AbstractIn this report, a split ring resonator (SRR), the most important building block of metamaterial, is fabricated and integrated with a microfluidic chamber for biosensing. The SRR is produced on a microwave printed circuit board while the microfluidic chamber is fabricated by casting of polydimethylsiloxane (PDMS). SRR was immobilized with Anti- Immunoglobulin G (IgG) for IgG detection by a standard covalent immobilization using Cystamine. The PDMS chamber was aligned and clamped on the circuit board and the electromagnetic response of the SRR sensor was continuously monitored when IgG analytes was flowed through the chamber. The reaction of Immunoglobulin G (IgG) and Anti-IgG results in a shift of resonance frequency. It was found that the response of the resonance frequency is sensitive to the IgG concentrations. Therefore, the SRR microfluidic scheme can be effectively used as an advanced bio-sensing device

Tactile Sensors Based on Conductive Polymers

This paper presents results from a selection of tactile sensors that have been designed and fabricated. These sensors are based on a common approach that consists in placing a sheet of piezoresistive material on the top of a set of electrodes. We use a thin film of conductive polymer as the piezoresistive mate¬rial. Specifically, a conductive water-based ink of this polymer is deposited by spin coating on a flexible plastic sheet, giving it a smooth, homogeneous and conducting thin film. The main interest in this procedure is that it is cheap and it allows the fabrication of flexible and low cost tactile sensors. In this work we present results from sensors made using two technologies. Firstly, we have used a flexible Printed Circuit Board (PCB) technology to fabricate the set of electrodes and addressing tracks. The result is a simple, flexible tactile sensor. In addition to these sensors on PCB, we have proposed, designed and fabricated sensors with screen printing technology. In this case, the set of electrodes and addressing tracks are made by printing an ink based on silver nanoparticles. The intense characterization provides us insights into the design of these tactile sensors.This work has been partially funded by the spanish government under contract TEC2006-12376-C02

Gasochromic response of Pd/NiO nanostructured film towards hydrogen

The gasochromic performance of nanostructured nickel oxide (NiO) films coated with 25 Å catalytic palladium (Pd) layer were investigated for low concentration hydrogen (H 2) sensing. NiO nanostructures of 20-30 nm sizes were produced via RF sputtering deposition of NiO x on quartz substrates and subsequently annealed at 500 °C. It was found that the Pd/NiO films show significant gasochromic response when exposed to H 2 at elevated temperatures. Integrating the absorbance change over a range of visible wavelengths (500-800 nm), has enabled very low concentrations of H 2 (0.06%) to be sensed in real time. T 90% response of 25 Å Pd/100 nm NiO film towards 0.06% H 2 in a balance of synthetic air was approximately 120 s at 170 °C. Similar H 2 concentration can be recovered in as little as 240 s at 170 °C

Characterization of n-type and p-type semiconductor gas sensors based on NiOx doped TiO2 thin films

This work presents the development of n-type and p-type gas-sensitive materials from NiOx doped TiO2 thin films prepared by ion-assisted electron-beam evaporation. TiO2 gas-sensing layers have been deposited over a wide range of NiOx content (0-10 wt.%). The material analysis by atomic force microscopy, X-ray photoemission spectroscopy, and X-ray diffraction suggests that NiOx doping does not significantly affect surface morphology and Ni element may be a substitutional dopant of the TiO2 host material. Electrical characterization shows that NiOx content as high as 10% wt. is needed to invert the n-type conductivity of TiO2 into p-type conductivity. There are notable gas-sensing response differences between n-type and p-type NiOx doped TiO2 thin film. The responses toward all tested reducing gases tend to increase with operating temperature for the n-type TiO2 films while the response decreases with temperature for p-type TiO2 film. In addition, the p-type NiOx doping results in the significant response enhancement toward tested reducing gases such as acetone and ethanol at low operating temperature of 300 ºC

Optical hydrogen sensing based on hybrid 2D MoO3/Au nanoparticles

© 2015 The Authors. Published by Elsevier Ltd. In this work for the first time, we report the use of molybdenum oxide (MoO3) nanoflakes on gold as active material for plasmonic optical gas sensor. The M0O3 flakes were deposited over a monolayer of gold nanoparticles, chemically attached to a functionalized fused silica substrate. The coupling between MoO3and gold nanoparticles led to reversible optical changes of the localized surface plasmon resonance of gold nanoparticles upon exposure to H2

Metamaterial-inspired microfluidic-based sensor for chemical discrimination

This work proposes a metamaterial-inspired microfluidic-based chemical sensor. The sensor comprises a microwave split-ring resonator (SRR), an important building block of metamaterials, integrated with a disposable flow-channel made of a transparency film. The electromagnetic response of the sensor is observed in the presence of various analytes including glycerol, ethanol, and phosphate buffered saline. It is found that the resonance frequency in the transmission amplitude and the zero crossing in the reflection phase of the sensor are good features for discrimination of these analytes and for determining their concentrations. The developed metamaterial-inspired microfluidic-based chemical sensor has a potential for advanced chemical sensing applications.Kata Jaruwongrungsee, Withawat Withayachumnankul, Anurat Wisitsoraat, Derek Abbott, Christophe Fumeaux, and Adisorn Tuantranon

Hydrogen and ozone SAW based gas sensors with RF magnetron sputtered InOx and electron beam evaporated SiNx

Abstract not availabl