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The purpose of this paper is to study the interaction of main marine organisms on localized corrosion of 316L stainless steel in the Dalian Sea area.

The steel plate was immersed in the Dalian Sea area for nine months to observe the biofouling and localized corrosion. The local potential distribution on the steel plate covered by marine organisms was measured. The local electrochemical measurements were performed to facilitate understanding the interfacial status under different biofouling conditions. The local surface morphologies and corrosion products were characterized.

The localized corrosion of stainless steel is mainly induced by the attachment of barnacles on the steel. The mussels have no influence on the localized corrosion. The cover of sea squirts could mitigate the localized corrosion induced by barnacles. Both crevice corrosion and pitting corrosion were found beneath the barnacle without the covering of sea squirts. The pitting damage was more serious than the crevice corrosion in the Dalian Sea area. The probing of sulfur element indicates that the potential growth of sulfate-reducing bacteria at barnacle center.

The above findings revealed that the interaction of marine organisms has significant influences on the localized corrosion of stainless steel. The influences of macro-fouling and micro-fouling on localized corrosion are discussed.

The purpose of this paper was to use the barnacle Amphibalanus amphitrite reared in the laboratory to investigate the effects of juveniles on corrosion behaviour of three stainless steels (SS): UNS S31600, N08904 and UNS S32760.

Barnacle larvae were maintained in a laboratory until they reached the cypris larval stage. A total of 100 cyprids were added to four individual containers; each SS coupon (70 × 50 × 2 mm3) was immersed into the containers. After the cyprids attached to the coupons, juveniles were reared for 21 days with the microalgae Skeletonema costatum (Greville) Cleve. Values of open circuit potential (OCP), breakdown potential (Eb) and polarisation resistance (Rp) were evaluated, along with surface examinations.

OCP differences between barnacles and control coupons were not apparent. However, the lowest values of Eb and Rp were observed in the presence of juvenile barnacles, demonstrating the SS corrosion caused by these organisms. Crevice corrosion around the base of the barnacles was detected during visual inspections, despite the small size of the barnacles and the short duration of the experiments.

The A. amphitrite assays were useful as a tool for testing corrosion behaviour of the SS under laboratory conditions. This was the first study to test the use of this common protocol in anti-fouling research as a method to study marine biocorrosion.

The problems of Super resolution are broadly discussed in diverse fields. Rather than the progression toward the super resolution models for real-time images, operating hyperspectral images still remains a challenging problem.

This paper aims to develop the enhanced image super-resolution model using “optimized Non-negative Structured Sparse Representation (NSSR), Adaptive Discrete Wavelet Transform (ADWT), and Optimized Deep Convolutional Neural Network”. Once after converting the HR images into LR images, the NSSR images are generated by the optimized NSSR. Then the ADWT is used for generating the subbands of both NSSR and HRSB images. The residual image with this information is obtained by the optimized Deep CNN. All the improvements on the algorithms are done by the Opposition-based Barnacles Mating Optimization (O-BMO), with the objective of attaining the multi-objective function concerning the “Peak Signal-to-Noise Ratio (PSNR), and Structural similarity (SSIM) index”. Extensive analysis on benchmark hyperspectral image datasets shows that the proposed model achieves superior performance over typical other existing super-resolution models.

From the analysis, the overall analysis of the suggested and the conventional super resolution models relies that the PSNR of the improved O-BMO-(NSSR+DWT+CNN) was 38.8% better than bicubic, 11% better than NSSR, 16.7% better than DWT+CNN, 1.3% better than NSSR+DWT+CNN, and 0.5% better than NSSR+FF-SHO-(DWT+CNN). Hence, it has been confirmed that the developed O-BMO-(NSSR+DWT+CNN) is performing well in converting LR images to HR images.

This paper adopts a latest optimization algorithm called O-BMO with optimized Non-negative Structured Sparse Representation (NSSR), Adaptive Discrete Wavelet Transform (ADWT) and Optimized Deep Convolutional Neural Network for developing the enhanced image super-resolution model. This is the first work that uses O-BMO-based Deep CNN for image super-resolution model enhancement.

The purpose of this paper is to develop a number of new anti‐fouling agents that are friendlier to the environment.

Seven copper(II) and cobalt complexes of 3‐(2‐furylidene) hydrazine‐5,6‐diphenyl‐1,2,4‐triazine (L) were prepared by interacting 3‐(2‐furylidene) hydrazino‐5,6‐diphenyl‐1,2,4‐triazine (L) with cobalt(II) and copper salts. The structures of the prepared complexes were confirmed by elemental analyses, IR and nujol mull electronic spectra, as well as magnetic susceptibility measurements. The anti‐fouling activity was measured on barnacle larvae.

The in vitro toxicity of the organic ligand and its cobalt and copper complexes on barnacle larvae was measured. The results indicated that the toxicity of the ligand increased upon complexation and that copper complexes are the most active ones.

Successful development of some new copper(II) and cobalt complexes of 1,2,4‐triazine that have in vitro anti‐fouling activity against barnacle larvae and might be safe to the marine environment.

In the protection against corrosion of lock gates and other harbour structures, the life expectation of the protection given is of major importance because of the high cost of drying off structures and repainting them. This paper discusses the factors involved and describes some case histories of marine protection.

Science, technology, engineering, mathematics and medicine (STEMM) workplaces worldwide remain stubbornly resistant to gender equality initiatives. Leaders are vital to driving change, but the extent to which their capabilities lead to change remains unknown. This article examines STEMM leaders' gender competence to achieving transformative changes in gender inequality.

This article examines the capability of STEMM leaders to act as change agents through an in-depth, qualitative analysis of perceptions of gender inequality, sexual harassment, sex discrimination and gender bias within their organisations. Findings are analysed using a customised tripartite gender competence schema, comprising commitment, knowledge and method (or know-how).

The findings suggest that while STEMM leaders may express a commitment to addressing gender inequality, misapprehensions about the nature and scope of the problem are likely to hamper efforts. Two key misapprehensions standout: a tendency to frame gender inequality in primarily numerical terms; and recourse to blaming external factors beyond STEMM for gender inequality in STEMM.

This article makes an original contribution by examining the gender competence of leaders in STEMM organisations, which has not been previously researched. The findings extend understanding of the salience of leaders' capabilities to lead change by identifying key gaps and misapprehensions in STEMM leaders' understanding of the nature and scope of the problem.

There is currently an ever increasing demand, particularly in the United States and Europe for paints and inks made from this powder. A very strong appeal for this powder, from its earliest use, whether in paint or ink applications has been due to the close resemblance it bears to gold. Its rich deep colour conveys a feeling of security and stability in an ever changing society. Bronze powder is in reality powdered brass and appears to have been used for the first time in Germany during the eighteenth century and was later introduced into Britain by Bessemer.

This topic covers a range of pigments and powders primarily developed to give lustre and brightness, and yet which have additional properties that enhance their appeal for a wide range of applications. They can be produced in many colours which are based on either nickel, aluminium, bronze or stainless steel.

Spurred by the COVID-19 pandemic, there has been an increase in the open acknowledgment of the importance of teaching and learning praxis that is grounded in compassion, understanding, cocreation, community, and flexibility. This is especially so for ‘traditional’ university spaces, in essence questioning and resisting the many established dynamics that face-to-face teaching and learning took for granted within many neoliberal and neocolonial higher education contexts. In this chapter, I propose positioning a love ethic as a primary point of departure for all educational engagements, a foundational shift in ontology (way of being) of the university. By focusing on love as liberation and justice, and teaching as an act of love, I draw on critical, engaged, and feminist pedagogies, as well as my experience as a lecturer in a social justice– and global citizenship-oriented program at the University of Cape Town (UCT), South Africa, where I positioned a love ethic as central to my pedagogical approach. I argue that when we begin to view love as more than mere emotion, but as an ideological position that informs values and praxis within higher education (and our university “classrooms” in particular), we may move toward new and exciting ways of envisioning the decolonized university of the 21st century. A love ethic, as defined by bell hooks, offers possibilities for an approach to critical transformation that is not merely motivated by the change of institutional structures, but by the reform of values guiding teaching and learning and ways of being within higher education institutions.