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The purpose of this paper is to highlight the relevant role of the stereochemistry of two Ruthenium catalysts on the self-healing efficiency of aeronautical resins.

Here, a very detailed evaluation on the stereochemistry of two new ruthenium catalysts evidences the crucial role of the spatial orientation of phenyl groups in the N-heterocyclic carbene ligands in determining the temperature range within the curing cycles is feasible without deactivating the self-healing mechanisms (ring-opening metathesis polymerization reactions) inside the thermosetting resin. The exceptional activity and thermal stability of the HG2_MesPhSyn catalyst, with the syn orientation of phenyl groups, highlight the relevant potentiality and the future perspectives of this complex for the activation of the self-healing function in aeronautical resins.

The HG2_MesPhSyn complex, with the syn orientation of the phenyl groups, is able to activate metathesis reactions within the highly reactive environment of the epoxy thermosetting resins, cured up to 180°C, while the other stereoisomer, with the anti-orientation of the phenyl groups, does not preserve its catalytic activity in these conditions.

In this paper, a comparison between the self-healing functionality of two catalytic systems has been performed, using metathesis tests and FTIR spectroscopy. In the field of the design of catalytic systems for self-healing structural materials, a very relevant result has been found: a slight difference in the molecular stereochemistry plays a key role in the development of self-healing materials for aeronautical and aerospace applications.

The purpose of this paper is to review the novel application of surface plasmon resonance (SPR) in sensing heavy metal ions and the development of SPR to become an alternative heavy metal ions sensor.

The possible dangerous toxic effects of heavy metal ions are revealed in the short introduction. The existing conventional methods for sensing heavy metal ions and their drawbacks are also discussed. To overcome these drawbacks, SPR has been investigated from the basic principle to the potential alternative in sensing heavy metal ions.

Application of SPR in sensing heavy metal ions emerged a decade ago. A wide range of active layers or recognition elements (e.g. polymer, protein, nanoparticles) have been developed to combine with SPR. The detection limit, sensitivity and selectivity of SPR sensing in heavy metal ions have been improved from time to time, until the present.

This paper provides up-to-date and systematic information on SPR sensing for heavy metal ions. Different advancements on active layers or recognition molecules have been discussed in detail and arranged in the order of their chronological evolution. The present review may provide researchers with valuable information regarding novel heavy metal ions sensor using SPR and encourage them to take this area for further research and development.

This paper aims to propose a new microfluidic portable experimental platform for quick detection of heavy metal ions (HMIs) in picomolar range. The experimental setup uses a microfabricated piezoresistive sensor (MPS) array of eight cantilevers with ion-selective self-assembled monolayer's (SAM).

Most of the components used in this experimental setup are battery operated and, hence, portable to perform the on-field experiments. HMIs (antigen) and thiol-based SAM (antibody) interaction start bending the microcantilever. This results in a change of resistance, which is directly proportional to the surface stress produced due to the mass of targeted HMIs. The authors have used Cysteamine and 4-Mercaptobenzoic acid as a thiol for creating SAM to test the sensitivity and identify the suitable thiol. Some of the cantilevers are blocked using acetyl chloride to use as a reference for error detection.

The portable experimental platform achieves very small detection time of 10-25 min with a lower limit of detection (LOD) 0.762 ng (6.05 pM) for SAM of Cysteamine and 4-Mercaptobenzoic acid to detect Mn2+ ions. This technique has excellent potential and capability to selectively detect Hg2+ ions as low as 2.43 pM/mL using SAM of Homocysteine (Hcys)-Pyridinedicarboxylic acid (PDCA).

As microcantilever is very thin and fragile, it is challenging to apply a surface coating to have selective detection using Nanadispenser. Some of the cantilevers get broken during this process.

The excessive use and commercialization of NPs are quickly expanding their toxic impact on health and the environment. Also, LOD is limited to nanomolar range. The proposed method used the combination of thin-film, NPs, and MEMS-based technology to overcome the limitation of NPs-based technique and have picomolar range of HMIs detection.

The purpose of this paper is to explore how employees in small and medium-sized enterprises (SMEs) practise and view workplace learning at three different life-cycle stages.

It is a qualitative study using a sample of 30 Hong Kong SMEs classified into inception, high-growth or maturity stage, from which firms in each stage were randomly selected and interviewed until data saturation was reached. Snowball sampling was adopted during interviews and data were examined through thematic analysis.

Consistent themes (patterns) from 134 semi-structured interviews are identified, addressing both similarities and differences in the nature of the practice of workplace learning in SMEs between life-cycle stages.

More similar comparative studies in other parts of the world, including quantitative surveys on larger samples, with either SMEs or multinational corporations, are encouraged to enrich the current findings.

If organisational growth is a priority, SME owner/managers should support employees’ work and learning in a timely fashion. As the study finds, individual learning and inter-organisational learning are considered “a must to have” for employees, regardless of which stage the firm is at. When an SME enters high-growth, however, more opportunities for group learning are particularly beneficial. For mature SMEs, it is essential for learning to move towards systemisation and include a professional development component to meet employees’ career expectations, not just their work demands.

The results advance the body of knowledge in SME learning from the life-cycle perspective. As one of the first studies in bridging these areas, it brings new implications to academic researchers and SME practitioners.

This paper aims to report an insightful portable microfluidic system for rapid and selective sensing of Hg²⁺ in the picomolar (pM) concentration using microcantilever-based piezoresistive sensor. The detection time for various laboratory-based techniques is generally 12–24 h. The majority of modules used in the proposed platform are battery oriented; therefore, they are portable and handy to carry-out on-field investigations.

In this study, the authors have incorporated the benefit of three technologies, i.e. thin-film, nanoparticles (NPs) and micro-electro-mechanical systems, to selectively capture the Hg²⁺ at the pM concentration. The morphology and topography of the proposed sensor are characterized using field emission scanning electron microscopy and verification of the experimental results using energy dispersive X-ray.

The proposed portable microfluidic system is able to perform the detection in 5 min with a limit of detection (LOD) of 0.163 ng (0.81 pM/mL) for Hg²⁺, which perfectly describes its excellent performance over other reported techniques.

A microcantilever-based technology is perfect for on-site detection, and a LOD of 0.163 ng (0.81 pM/mL) is outstanding compared to other techniques, but the fabrication of microcantilever sensor is complex.

Many researchers used NPs for heavy metal ions sensing, but the excess usage and industrialization of NPs are rapidly expanding harmful consequences on the human life and nature. Also, the LOD of the NPs-based method is limited to nanomolar concentration. The suggested microfluidic system used the benefit of thin-film and microcantilever devices to provide advancement over the NPs-based approach and it has a selective sensing in pM concentration.

The Electroplating Products and Equipment Business Area of Degussa AG, Frankfurt am Main, Federal Republic of Germany, has begun to supply a new selective electroplating plant. Under a co‐operation agreement with the Telmec company of Milan, Italy, this business area of Degussa, which is based in Schwäbisch Gmüd, Germany, has begun to market the Telmec SL 6 ‘Tab Plater’ throughout the world, with the exception of Italy and France. The equipment was developed specially for manufacturers of printed circuit boards, and is used for the continuous electroplating of strip contacts on these boards.

This paper aims to study the effect of Hg²⁺ on the corrosion behavior of Al–2%Zn coatings on AA5083 in 3.5 Wt.% NaCl solution.

Potentiodynamic polarization and electrochemical impedance spectroscopy are used to investigate the effect of Hg²⁺ on the corrosion behavior. The surface and cross-sectional morphology are characterized by scanning electron microscopy and energy dispersive spectroscopy (EDS) to further reveal the corrosion mechanism of Hg²⁺.

The results show that the corrosion behavior of the coating changes significantly as the concentration of Hg²⁺ increases from 5 to 30 μg/L. The corrosion production film can inhibit the corrosion process when Hg²⁺ concentration is in the range of 0.5–5 μg/L, while Hg²⁺ can promote the corrosion process significantly when its concentration reaches to 30 μg/L. The generation rate of dense oxide film on the coating surface is faster than dissolution rate when the concentration of Hg²⁺ is in the range of 0–5 μg/L, which makes the coating “self-healing” and thus slightly slows down the corrosion rate. The EDS analysis shows that excessive Hg²⁺ are preferentially deposited at locations with inhomogeneous electrochemical properties, which in turn accelerates corrosion.

The corrosion resistance of Al-based coatings is significantly affected by Hg²⁺ in seawater. Thus, it is important to explain the corrosion mechanism of Al–2%Zn coatings under the combined effect of Hg²⁺ and Cl⁻ in 3.5 Wt.% NaCl solution.

This study aims to understand how public sector organizations can successfully implement organizational information systems (IS). It identifies the factors that contribute to the success of organizational IS implementation in public universities.

Both qualitative and quantitative research methods are used. The proposed research model is based on previous studies and primary qualitative research, including in-depth interviews, telephone surveys and mail surveys using semi-structured questionnaires to identify the determinants and measures of implementation success. Based on the first mail survey’s results, quantitative research is conducted to test the research hypotheses. The data are gathered from university personnel at 40 public universities, and the study focuses on the implementation of student registration systems.

The results suggest that successful implementation of organizational IS includes the decisions of both those in authority and users. The external and internal organization and individual user factors have direct relationships with the measure of implementation success, which suggests significant differences between authorities and users.

The analysis is based on the viewpoint of public university personnel; however, the findings suggest the need for further research on other public organizational IS as well as other public service operations.

The study clearly suggests a set of factors to guide public universities in successfully implementing organizational IS for local conditions of a developing country.

The study contributes to the understanding of effective IS implementation in public universities in a developing country.

This information will be useful in the selection of materials and technology for the detection and removal of mercury ions at a low cost and with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity. The purpose of this study is to provide the useful information for selection of materials and technology to detect and remove the mercury ions from water with high sensitivity and selectivity.

Different nano- and bio-materials allowed for the development of a variety of biosensors – colorimetric, chemiluminescent, electrochemical, whole-cell and aptasensors – are described. The materials used for their development also make it possible to use them in removing heavy metals, which are toxic contaminants, from environmental water samples.

This review focuses on different technologies, tools and materials for mercury (heavy metals) detection and remediation to environmental samples.

This review gives up-to-date and systemic information on modern nanotechnology methods for heavy metal detection. Different recognition molecules and nanomaterials have been discussed for remediation to water samples. The present review may provide valuable information to researchers regarding novel mercury ions detection sensors and encourage them for further research/development.

There have been long‐standing difficulties with the recruitment of medical students into psychiatry. One of the reasons for this may be the perceived stigma attached to the profession. The aim of this paper is to assess whether a brief intervention could help to alter attitudes towards psychiatry in students undertaking clinical attachments with psychiatry components. An evidence‐based intervention was delivered to fourth year medical students. Their attitudes towards the specialty were measured with the ATP‐30 questionnaire in order to establish any effect. The intervention may have been associated with a temporary improvement in attitudes, which attenuated during the course of their clinical placements. Unexpectedly, it appeared that placements themselves may have contributed to a negative impact. Female students and those from a healthcare background were more likely to have positive views. Although single brief interventions may have only a limited effect in combating stigma in medical student's attitudes, placement experience appears to play a significant role, which requires further study.