Tadeja Kosec

The advanced coupled multi-electrode array (CMEA) technique provides spatiotemporal insights into electrochemical processes. This study used the CMEA technique to monitor the distribution of anodic and cathodic activity during galvanic interactions between copper and steel. An important parameter influencing the intensity of galvanic corrosion is the anode-to-cathode area ratio, which was also investigated. After exposure, corrosion products were analyzed using microscopic and spectroscopic techniques, and the extent of actual corrosion damage was evaluated using µ -CT. In the CMEA sensor with a Cu:CS ratio of 24:1, the corrosion rate of the CS electrode was estimated at 0.86 mm year ⁻¹ . For the area ratio of Cu:CS 22:3, a lower corrosion rate of 0.56 mm year ⁻¹ was observed for the CS electrodes. The influence of the reduction process on copper electrodes and the intensity of galvanic corrosion is demonstrated. The main corrosion products on the CS electrodes were goethite, lepidocrocite, and akaganeite, indicating a corrosion process involving oxygen. The copper electrodes acted as cathodes, but some individual Cu electrodes also exhibited anodic activity. This suggests simultaneous anodic and cathodic activity, and the anodic activity was confirmed by Raman spectroscopy, which detected the presence of Cu ₂ O. Cu ₂ S was also detected, indicating corrosion processes involving bisulfide ions.

Failure of various components in internal drinking water systems leads to water leakage and high economic costs. Brass is a promising material for machining such components; however, it is sensitive to special forms of corrosion. Dezincification of duplex (α+β') brass can cause dealloying and cracking of components and also lead to the release of lead into drinking water, which is one of the greatest health concerns in these systems. In the present study, the microstructure and fractures of three brass components that cracked a short or moderate time after the start of operation were investigated. The investigation showed their sensitivity to cracking regardless of the presence of a corrosive environment.

According to the fact sheet on the gender gap in science published by UNESCO’s Institute for Statistics (UIS) in February 2024 (UIS, 2024), women still account for a minority of the world’s researchers: overall, approximately one in three researchers are women. Taking into account all the data gathered by the UIS since 1996, representing 147 countries reporting on female researchers or research and development personnel in headcounts or full-time equivalents, the percentage of women researchers globally is 31.7% in 2021.Despite the growing demand for cross-nationally comparable statistics on women in STEM (science, technology, engineering, and mathematics), national data and their use in policymaking often remain limited. Over the past decade (2012 to 2021), 130 countries reported the share of women researchers in national science, technology and innovation systems. The shares of female researchers for 2021 by region are:• 31.7% for World (↗ up from 30.9% in 2011)• 49.6% for Central Asia (↗ up from 44.7% in 2011)• 44.4% for Latin America and the Caribbean (≈ slightly lower than 44.9% in 2011)• 41.1% for Arab States (↗ up from 37.7% in 2011)• 38.7% for Central and Eastern Europe (↘ down from 40.5% in 2011)• 33.9% in Western Europe (↗ up from 31.8% 2011)• 31.5% for Sub-Saharan Africa (↗ up from 29.1% in 2011)• 26.8% for East Asia and the Pacific (↗ up from 21.1% in 2011)• 25.9% in South and West Asia (≈ stable compared to 25.7% in 2011)• No regional value for North America (Canada and the USA do not report internationally comparable data on share of female researchers)These trends in regional and global averages, which should be considered as estimates, show that the evolution is slow, and that the scattering between regions remains high, the shares varying from single to double for example between the lowest (25.9%) and the highest (49.6%) observed values.As role models are important to show to younger generations the growing impact of female researchers to science, and continuing the spirit of the International Day of Women and Girls in Science, Frontiers in Materials has decided to offer a platform to bring into the spotlight, highlight the impact, and promote the contributions and research outcomes of female scientists from different parts of the world working in materials science and engineering.Following the first two editions (Bignozzi et al., 2021, Krawczak et al., 2023), this 3rd volume of the “Women in Science: Materials” article collection (Figure 1) gathers a selection of original articles with the lead author and/or corresponding author being a woman.Nine contributions (one perspective, one review and seven original research articles) present advances in theory, experiment, and methodology with applications to compelling problems, across different sections of the journal: Biomaterials and Bio-Inspired Materials: In a perspective paper, Danti and Berrettini have highlighted to what extent getting to nano can open new horizons for piezoelectric material-based cochlear implants. By combining nanostructured non-biodegradable biomaterials and an efficient surgical implantation based on tissue engineering approach, the envisioned piezoelectric device could be optimized in terms of reduced electric output and improved level of sensitivity. Foti et al. have proposed an innovative methodology for the effective removal of cetyltrimethylammonium bromide (CTAB), surfactant commonly used in the synthesis of gold nanorods (AuNR). The reported approach is based on a combination of ligand replacement and surface bioconjugation processes that efficiently removes CTAB and simultaneously functionalizes nanorods with hyaluronic acid (HA) to enhance their biocompatibility and introduce targeting capabilities toward cancer cells. Mellinas et al. have formulated and produced novel antioxidant/antifungal active films as promising alternatives to the traditional petrol-derived systems at the industrial scale. The developed films, produced by means of melt-blending followed by compression-moulding, are based on bio-polyethylene (BPE) added with Nutrabiol®T90 and Tocobiol®Plus natural extracts rich in tocopherols at different concentrations (1 and 3 wt%). The obtained films have been fully characterised in terms of barrier, mechanical, optical and functional properties. Environmental Degradation of Materials: Lors et al. have reviewed the progress made in the field of biodegradability of bio-based plastics based on polylactic acid (PLA). In particular, the main biodegradation mechanisms have been reviewed according to aerobic and anaerobic conditions, as well as the different microorganisms involved in the PLA degradation. Additionally, the analytical methods used to evaluate the PLA biodegradation have also been illustrated. Polymeric and Composite Materials: Yilmaz Attay and Bilgiç have developed new radar absorbing materials made of carbon nanotubes reinforced polymer composites to reduce the reflection of electromagnetic waves. In response to the issue of natural resource shortages in building and construction, Zambon and Lagardère have explored the potential for material valorization of shredded glass fiber / unsaturated polyester composites waste in mortar and concrete as a substitute to sand. Kayishaer et al. have investigated the electrodeposition of polyaniline films with an original focus on the modulation of the conductivity, capacitance and electroactivity of the films using surfactants of different polarity. Mechanics of Materials: Franzoni and Pizzigatti have investigated the performance of different repair mortars in terms of efficacy, compatibility and durability of an historic reinforced concrete floor slab in the context of 20th century architectural heritage conservation. Structural...

Atmospheric pollutants in the air form acid rain which interacts with bronze surfaces exposed in urban outdoor environment. In this study, different types of patinas on bronze were investigated during and after 9 years of exposure to urban environment in moderately polluted continental city. Natural bronze patina and artificial brown sulphide, green chloride, and green–blue nitrate patinas were investigated. Visual assessment was carried out at defined periods. After 9 years of exposure, an electrochemical study was performed to investigate the electrochemical activity of the patinas in artificial urban rain. Additionally, the patinas were characterised using a variety of techniques, including metallographic examination, scanning electron microscopy/energy dispersive X-ray spectroscopy, Raman spectroscopy, X-ray diffraction analysis, X-ray-photoelectron spectroscopy, and time-of-flight secondary ion mass spectrometry to analyse the surface morphology, chemical composition, and stratigraphic features of the patinas. Evolution of the patinas was shown to be a result of both, the composition of the acid rain and the hydrophobicity of the patinated surfaces.

In the case of a two‐part container for spent nuclear fuel, consisting of an iron‐based inner structure with a copper coating, the potential perforation of copper through minor damage may result in intensive galvanic corrosion between copper and steel. The present work focuses on the corrosion of steel galvanically coupled to copper and exposed to a slightly saline environment under oxic conditions. The electrochemical processes on individual electrodes were monitored by coupled multielectrode arrays (CMEAs). The CMEAs were either in contact with groundwater saturated with bentonite or immersed in groundwater only. Very high galvanic corrosion currents were detected between carbon steel and pure copper in the early oxic phase. Additionally, the use of CMEAs further made it possible to monitor the distribution of cathodic currents around the steel electrode, which behaved anodically. Various microscopy and spectroscopy techniques were applied to identify the modes of corrosion and the type of corrosion products present at the end of the period of exposure.