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The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton exchange membrane fuel cells (PEMFCs), a protective Nb-modified layer is formed onto stainless steel via the plasma surface diffusion alloying method. The effect of diffusion alloying time on electrochemical behavior and surface conductivity is evaluated.

In this work, the surface electrical conductivity and corrosion resistance of modified specimen are evaluated by the potentiodynamic and potentionstatic polarization tests. Moreover, the hydrophobicity is also investigated by contact angle measurement.

The Nb-modified 430 SS treated by 1.5 h (1.5Nb) presented a lower passivation current density, lower interfacial contact resistance and a higher hydrophobicity than other modified specimens. Moreover, the 1.5 Nb specimen presents a smoother surface than other modified specimens after potentionstatic polarization tests.

The effect of diffusion alloying time on electrochemical behavior, surface conductivity and hydrophobicity of modified specimen is evaluated. The probable anti-corrosion mechanism of Nb-modified specimen in simulated acid PEMFC cathode environment is presented.

The purpose of this study is to improve the surface electrical conductivity and corrosion resistance of AISI430 stainless steel (430 SS) as bipolar plates for direct formic acid fuel cell (DFAFC).

The niobium diffusion layers have been successfully synthesized on 430 SS substrate by the plasma surface diffusion alloying technique under different diffusion alloying time.

The surface morphology of Nb-modified 430 SS prepared under the diffusion alloying time of 2 h is more homogeneous, relatively sleek and compact without surface micropore and other common surface blemishes. The potentiostatic and potentiodynamic polarization measurements manifest that Nb-modified 430 SS prepared under the diffusion alloying time of 2 h enormously ameliorate the corrosion resistance of bare 430 SS compared with other Nb-modified 430 SS samples and its corrosion current density is maintained at −1.4 µA cm⁻² in simulated anodic environment of DFAFC (0.05 M H₂SO₄ + 2 ppm HF + 10 M formic acid at 50 °C).

The effect of diffusion alloying time on the corrosion resistance and surface conductivity of Nb-modified 430 SS has been carefully studied. The Nb-modified 430 SS samples prepared at the diffusion alloying time of 2 h have the best surface electrical conductivity and corrosion resistance in the simulated anodic environment of DFAFC.

The paper's aim is to investigate the mixed convection flow of an electrically conducting and viscous incompressible fluid past an isothermal vertical surface with Joule heating in the presence of a uniform transverse magnetic field fixed relative to the surface. It was assumed that the electrical conductivity of the fluid varies linearly with the transverse velocity component.

The governing boundary layer equations were solved numerically. The boundary layer equations were first reduced to a convenient form by using two different formulations, namely, (i) the stream function formulation (SFF) and (ii) primitive variable formulation (PVF).

It was observed that both the local shear‐stress and Nusselt number increase with increasing value of local magnetic parameter, ξ.

In the present investigation, we investigated the effects of Joule heating on MHD mixed convection boundary layer flow of an electrically conducting viscous incompressible fluid past an isothermal vertical flat plate in the presence of a transverse magnetic field fixed relative to the surface of the plate. The analysis was valid for a steady, two dimensional laminar flow. An extension to three dimensional flow case is left for future work.

Here we have analyzed the problem of mixed convection flow of electrically conducting and viscous incompressible fluid past an isothermal vertical surface with viscous and Joule heating in presence of a uniform transverse magnetic field fixed relative to the surface. The work would be useful in the thermal management of heat transfer devices.

The results of this study may be of interest to engineers interested in heat exchanger design.

Examines the fourteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

This work aims to investigate the direct production of electrical discharge machining (EDM) electrodes by means of the selective laser sintering (SLS) technique using a new non-conventional metal-matrix composite material (TiB₂-CuNi). The influence and optimization of the main SLS parameters on the densification behavior and porosity is experimentally studied. EDM experiments are also performed to evaluate the electrodes performance.

The new EDM electrode material used was a powder system composed of TiB₂ and CuNi. Making use of a designed systematic experimental methodology, the effects of layer thickness, laser scan speed and scan line spacing were optimized, where aspects such as densification behavior, porosity and surface morphology of the samples were analyzed through microstructural and surface analysis. EDM experiments were conducted under three different regimes in order to observe the electrodes behavior and performance. The results were compared with copper powder electrodes manufactured by SLS and EDMachined under the same conditions.

The experimental results showed that the direct SLS manufacturing of composite electrodes is feasible and promising. The laser scan speed has a high effect on the densification behavior of the samples, while the effect of scan line spacing on the porosity is more visible when the overlapping degree is considered. Surface morphology was not affected by the scan line spacing, whereas balling phenomenon was reported, regardless of the scan line spacing. The EDM results showed that the TiB₂-CuNi electrodes had a much superior performance than the copper powder electrodes made by SLS, regardless of the EDM regime applied.

Generally, the machine tool itself promotes some restrictions to the SLS process optimization. It is normally attributed to the characteristics of the laser type and the amount of energy that can be delivered to the powder bed. The present investigation could not cover all the optimization potential involved with the studied material due to limitations of the SLS machine tool used.

Significant results on the direct SLS manufacturing of a new non-conventional composite material, which has a great technological potential to be used as an EDM electrode material, are presented. Valuable guidelines are given in regard to the SLS optimization of TiB₂-CuNi material and its performance as an EDM electrode. This work also provides a systematic methodology designed to be applied to the SLS process to produce EDM electrodes.

Examines the fifthteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Examines the fifteenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

This review provides an overview of recent advances in electrochemical sensors for analyte detection in saliva, highlighting their potential applications in diagnostics and health care. The purpose of this paper is to summarize the current state of the field, identify challenges and limitations and discuss future prospects for the development of saliva-based electrochemical sensors.

The paper reviews relevant literature and research articles to examine the latest developments in electrochemical sensing technologies for saliva analysis. It explores the use of various electrode materials, including carbon nanomaterial, metal nanoparticles and conducting polymers, as well as the integration of microfluidics, lab-on-a-chip (LOC) devices and wearable/implantable technologies. The design and fabrication methodologies used in these sensors are discussed, along with sample preparation techniques and biorecognition elements for enhancing sensor performance.

Electrochemical sensors for salivary analyte detection have demonstrated excellent potential for noninvasive, rapid and cost-effective diagnostics. Recent advancements have resulted in improved sensor selectivity, stability, sensitivity and compatibility with complex saliva samples. Integration with microfluidics and LOC technologies has shown promise in enhancing sensor efficiency and accuracy. In addition, wearable and implantable sensors enable continuous, real-time monitoring of salivary analytes, opening new avenues for personalized health care and disease management.

This review presents an up-to-date overview of electrochemical sensors for analyte detection in saliva, offering insights into their design, fabrication and performance. It highlights the originality and value of integrating electrochemical sensing with microfluidics, wearable/implantable technologies and point-of-care testing platforms. The review also identifies challenges and limitations, such as interference from other saliva components and the need for improved stability and reproducibility. Future prospects include the development of novel microfluidic devices, advanced materials and user-friendly diagnostic devices to unlock the full potential of saliva-based electrochemical sensing in clinical practice.

To model magneto‐harmonic devices including solid conductors with holes when the skin depth is very small.

The 3D finite element magnetic scalar potential formulation combined with the surface impedance condition approximation is used. It allows the modelling of thin skin depth effect at low cost.

The paper shows how to use surface impedance condition for solid conductors with holes, when using the magnetic scalar potential. Specific equations must be added to respect Ampere's theorem. The paper establishes these equations and the coupling with the finite element formulation. The final system of equations is symmetric.

The formulation allows to treat linear material in the magneto‐harmonic assumption.

The use of surface impedance condition with the 3D finite element magnetic scalar potential formulation is well known. The originality is to take into account holes (multiply connected conductors).

This paper discusses the MIL‐P‐28809 Cleanliness Standard and Test, the reasons for testing, how to test, how much it will cost and what the benefits and limitations are.