Johnson Matthey Technology Review - Current Issue

Research on building energy efficiency has increased significantly over the past twenty years, creating a complex and fragmented landscape that complicates a thorough comprehension of the field’s development and present condition. This study utilises a mixed-method approach that integrates bibliometric analysis and systematic literature review to investigate the building energy efficiency research environment from 2003 to 2023. We examined 1458 papers from the Scopus^® database, concentrating on publication trends, collaborative networks, research themes and emerging issues. Research on building energy efficiency has expanded significantly, exhibiting a compound annual growth rate of 15.3% in publications. Artificial intelligence, the internet of things and improved materials are crucial catalysts of contemporary advancements. Collaborations among academics, industry and policymakers have increased, promoting more applied research. This two-part paper presents the inaugural complete, longitudinal examination of the building energy efficiency research environment, elucidating its evolution, present condition and prospective trajectories.

This is Part II of a study utilising a mixed-method approach that integrates bibliometric analysis and systematic literature review to investigate the building energy efficiency research environment from 2003 to 2023. China, the USA and European nations are prominent contributors to building energy efficiency research. The emphasis of research has transitioned from individual building elements to comprehensive, systems-oriented methodologies. We delineate research gaps and emerging trends, providing a framework for researchers, policymakers and practitioners to progress in the domain of building energy efficiency.

Electrical discharge machining (EDM) is a highly effective and widely utilised unconventional manufacturing technology primarily used to produce complicated forms in materials that are challenging to machine. This versatile manufacturing approach finds applications in producing diverse items such as surgical instruments, aerospace components, automotive parts, dies and moulds. Despite its manifold advantages, this method presents notable drawbacks, including relatively modest material removal rates (MRR), significant tool wear rates (TWR), electrode wear ratio (EWR) and notable surface roughness (SR). The current paper examines numerous approaches used by researchers to enhance the functionality of EDM and the scope for upcoming research. The effects of various circuit and non-circuit characteristics on performance metrics like MRR, TWR and SR are listed. The impact of different electrode material, dielectrics and their alterations on machining performance are carefully examined. Furthermore, the paper elucidates a range of advanced EDM iterations developed to enhance performance through cutting-edge technologies. It delves into research findings concerning the environmental sustainability of EDM. It also examines various theoretical models that have been put out to describe EDM’s spark generation and material removal processes. The review’s final section provides a summary of the potential areas for EDM research in the future. The investigation has shown that material removal in EDM is a complicated process. The correct electrode and dielectric material must be chosen and their properties must be adjusted to fit the type of workpiece material for it to be effective. The choice of circuit parameters is also affected by the type of workpiece material. The effectiveness of EDM in machining metal matrix composites (MMCs), ceramics and nanomaterials requires more investigation.

This review is focused on ‘frustrated Lewis pair’ (FLP) hydrogenations. Following a discussion of the conceptual discovery and initial efforts to exploit the finding for metal-free hydrogenations, the scope of substrates that are susceptible to FLP hydrogenations are considered. The further advancement of FLPs to enantioselective reductions are discussed. Applications of the concept in transfer hydrogenation, and the reductions of carbon dioxide and main group substrates are also presented. Finally, the utility of the concept of FLPs in several heterogeneous catalysis systems is considered. The review concludes with an outlook for the future of FLP reductions.

Slurry erosion is a mechanically induced wear observed in various industries transiting the mixture of liquid and erodent particles, either naturally or affectedly. The equipment and pipelines need frequent monitoring and slurry erosion prediction to check the severity of erosion for implementing preventive measures to minimise the damage of erosion wear. Experimental investigation and online condition monitoring are very high priced and provide a fair idea about the extent of slurry erosion wear; nevertheless, precise prediction of slurry erosion wear requires in situ operating conditions. To minimise expenditure on slurry erosion testing or monitoring and accurate slurry erosion prediction, tribological modelling of slurry erosion wear by mathematical approach or computer-based simulations has proved to be an excellent approach by numerous researchers to foresee the slurry erosion wear and control its severity. Several authors in the past have aligned their efforts in this direction. This two-part review is an attempt to estimate the progress in the variety of tribological modelling (primarily mathematical models) of slurry erosion for its forecasting, monitoring and to suggest the apt approach for the modelling of slurry erosion wear, especially for hydroturbine components. This article covers the research studies pertaining to mathematical wear models for solid particle erosion recommending a commencing approach for slurry erosion wear modelling.

This article is Part II of a review of the progress in the variety of tribological modelling (primarily mathematical models) of slurry erosion for its forecasting, monitoring and to suggest the apt approach for the modelling of slurry erosion wear, especially for hydroturbine components. There is a discussion of mathematical modelling, irregularly shaped erodent particles and computer-simulation based models. Future scope and conclusions of this research are presented.