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Reducing noise and vibration is an increasingly important objective for designers and users of a wide range of mechanical systems. Lubricants can contribute to reduction of overall noise and vibration generated by machines, both by reducing generation of acoustic energy in lubricated contacts and by modulating the transmission of vibration through the lubricant. This paper outlines various mechanisms by which the lubricant may affect the generation and transmission of acoustic vibration. Examples from the area of refrigeration compressor lubrication are presented, demonstrating that correct design and selection of lubricant can have a significant impact on noise and vibration.

This study aims to investigate the behavior of vegetable oil with two additives. Base oil’s tribological qualities can be improved with the help of several additions. In the present investigation, soybean oil is served as the foundational oil due to its eco-friendliness and status as a vegetable oil with two additives, named polytetrafluoroethylene (PTFE) and molybdenum disulfide (MoS₂).

As additives, PTFE and MoS₂ are used; PTFE is renowned for its anti-friction (AF) properties, while MoS₂ is a solid lubricant with anti-wear (AW) properties. This investigation examines the synergistic impact of AF and AW additions in vegetable oil. The lubricity of the base oil is measured by using a four-ball tester, and the wear properties of the oil at different additive amounts are determined by using a universal tribometer.

PTFE (at 5 Wt.%) and MoS₂ (at 1 Wt.%) were found to improve the tribological performance of the base oil. The weld load is significantly increased when 5 Wt.% of PTFE + MoS₂ is added to the base oil.

A better tribological characteristic can be achieved by combining additives that amount to less than 1% of the base oil. In experiments with highly concentrated MoS₂, the adequate pressure improved dramatically, but the lubricant’s tribological characteristics did not.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0321/

The purpose of this paper is to investigate the tribological behaviour of commercially available SAE 10 mineral and rapeseed oils containing Fe particles synthesized directly in the oil phase.

Sub-micron Fe particles (50-340 nm) were synthesized by wet chemical reduction reaction of FeSO₄ by sodium borohydride in the rapeseed and mineral oils in the presence of surfactant: block copolymer (ENB 90R4) or oxyethylated alcohol (OS-20). A four-ball wear tribometer was used to investigate the tribological properties of mineral and rapeseed oil: coefficient of friction (COF), wear scar diameter and wear loss. Viscosity measurements of oil solutions and determination of synthesized Fe particles size were performed as well.

The presence of Fe particles (0.1 weight per cent) in the rapeseed and mineral oils caused the little change in the COF but resulted in marked improvement of anti-wear property. The oils containing Fe particles with slightly higher viscosity are giving more friction due to viscous drag. The anti-wear enhancement is attributed to the formation of tribofilm and superior load-bearing capability of the modified oil. Both rapeseed and mineral oils irrespective of used surfactant in the presence of 0.1 weight per cent Fe particles (50-140 nm) show sufficiently improved anti-wear properties.

The data collection about tribological behaviour of oils containing Fe particles and various additives in lubricants has a practical interest. The findings could be helpful to increase the knowledge of the behaviour of real tribological systems, where the metallic debris are generated during friction and contaminate the lubricating oil.

The purpose of this paper is to understand the impacts of oleoyl glycine on biodegradation, friction and wear performances of a mineral lubricating oil.

The biodegradabilities of a neat oil and its formulations with oleoyl glycine were evaluated on a biodegradation tester and the microbial characters in the biodegradation sewage observed through a microscope. Also, the friction and wear performances of neat oil and the formulated oil were determined on a four‐ball tribometer. The morphologies and tribochemical features of the worn surfaces were analyzed by scanning electron microscopy and X‐ray photoelectron spectroscopy.

Oleoyl glycine markedly enhanced biodegradation of unreadily biodegradable mineral oil and effectively improved its anti‐wear and friction‐reducing abilities. The enhancement of biodegradability of the mineral oil was preliminarily ascribed to the increment of microbial populations in the biodegradation processes, while the improvement of anti‐wear and friction‐reducing abilities was mainly attributed to the formation of a boundary adsorption film of oleoyl glycine on the friction surfaces.

Oleoyl glycine is a biodegradable and low eco‐toxic compound. The authors' work has shown that oleoyl glycine is effective in improving biodegradability and tribological performances of mineral lubricants. Enhancing biodegradability of petroleum‐based lubricants by additives is a new attempt. The paper has significance for improving ecological and tribological performances of mineral lubricants, even for developing petroleum‐based biodegradable lubricants.

The paper presents the results of research carried out on esters of carbonic, adipic, and sebacic acids with respect to their use as components of fully synthetic lubricating oil produced from a polyalphaolefin base. Straight dicarboxylic acid esters were synthesized in a transesterification reaction of dimethyl carbonate, dimethyl adipate, and dimethyl sebacate with 2‐ethylhexanol and 3,5,5‐trimethylhexanol.

Oligomeric esters of adipic acid and sebacic acid were synthesized using neopentyl glycol, appropriate dimethyl adipate or dimethyl sebacate and 2‐ethylhexanol as the starting material. The basic physicochemical properties of esters were determined and their compatibility with synthetic oils were defined. They were also evaluated with respect to resistance under the influence of thermo‐oxidative factors, evaporation and susceptibility to hydrolytic decomposition. The selected esters were complemented with commercial additives to make up a fully synthetic lubricating oil with a polialphaolefin base. A special attention was paid to the effect of ester compounds on the physicochemical properties of the formulated oil.

The obtained results show that straight adipates and sebacates of 2‐ethylhexanol and 3,5,5‐trimethylhexanol as well as oligomeric esters in which molecules are terminated with 2‐ethylhexyl group can be used as component of lubricating oils. The addition of these esters reduced the pour point by a few degrees in comparison with the tested base oil. The temperature fell below 40°C. The presence of esters significantly improved the viscosity index. A positive influence of esters on the lubricating properties of the formulated oil was also observed. On the contrary, dialkyl carbonates show too low boiling point, which is indicated by the high amount of volatile components, 19‐22 percent, in final product. Adipic and sebacic oligomers containing methoxyl groups in their structures proved to be immiscible with polyalphaolefins.

The achievement of this work is the synthesis of new oligomeric esters of dicarboxylic acids, which can be excellent additives for improving properties of synthetic oils. Further studies will be focused on the use of esters as components of engine oils. This requires real motor tests.

In North America, delegated practice “medical direction” models are often used as a proxy for clinical quality and safety in paramedic services. Other developed countries favor a combination of professional regulatory boards and clinical governance frameworks that feature paramedics taking lead clinician roles. The purpose of this paper is to bring together the evidence for medical direction and clinical governance in paramedic services through the prism of paramedic self-regulation.

This narrative synthesis critically examines the long-established North American Emergency Medical Services medical direction model and makes some comparisons with the UK inspired clinical governance approaches that are used to monitor and manage the quality and safety in several other Anglo-American paramedic services. The databases searched were CINAHL and Medline, with Google Scholar used to capture further publications.

Synthesis of the peer-reviewed literature found little high quality evidence supporting the effectiveness of medical direction. The literature on clinical governance within paramedic services described a systems approach with shared responsibility for quality and safety. Contemporary paramedic clinical leadership papers in developed countries focus on paramedic professionalization and the self-regulation of paramedics.

The lack of strong evidence supporting medical direction of the paramedic profession in developed countries challenges the North American model of paramedics practicing as a companion profession to medicine under delegated practice model. This model is inconsistent with the international vision of paramedicine as an autonomous, self-regulated health profession.

Positive behavioural support (PBS) as a framework for delivering quality services is recognised in important policy documents (CQC, 2020; NICE, 2018), yet there is an absence in the literature on how this could be implemented on a large scale. The purpose of this paper is to describe a recent implementation of a workforce strategy to develop PBS across social care and health staff and family carers, within the footprint of a large integrated care system.

A logic model describes how an initial scoping exercise led to the production of a regional workforce strategy based on the PBS Competence Framework (2015). It shows how the creation of a regional steering group was able to coordinate important developmental stages and integrate multiple agencies into a single strategy to implement teaching and education in PBS. It describes the number of people who received teaching and education in PBS and the regional impact of the project in promoting cultural change within services.

This paper demonstrates a proof of concept that it is possible to translate the PBS Competency Framework (2015) into accredited courses. Initial scoping work highlighted the ineffectiveness of traditional training in PBS. Using blended learning and competency-based supervision and assessment, it was possible to create a new way to promote large-scale service developments in PBS supported by the governance of a new organisational structure. This also included family training delivered by family trainers. This builds on the ideas by Denne et al. (2020) that many of the necessary building blocks of implementation already exist within a system.

A co-ordinated teaching and education strategy in PBS may help a wide range of carers to become more effective in supporting the people they care for.

This is the first attempt to describe the implementation of a framework for PBS within a defined geographical location. It describes the collaboration of health and social care planners and a local university to create a suite of courses built around the PBS coalition competency framework.

This paper argues that currently management accounting is simply too narrow and proposes how to broaden its scope to make it more relevant and useful.

The approach is to provide a critique of the extent to which management accounting sufficiently deals with three primary areas that classic management accounting has been myopic about at least to some extent: Organizational control, Organizational measurement, and Intellectual assets.

The paper argues that management accounting has not taken a “deep dive” into these areas and has placed itself at risk of being marginalized. It presents potential frameworks and tools of organizational control, organizational measurement, and intellectual assets as “add-ons” to management accounting to increase its relevance and utility.

The paper shows how management accounting must be broadened to include all organizational measurement and accountability for planning and control.

The paper describes several global applications of the proposed revised frameworks, methodologies, and tools presented as potential add-ons to management accounting. These applications demonstrate the feasibility, utility, and generalizability of the broader management accounting “tool box” presented.

The paper proposes a revised paradigm for management accounting. This paradigm is original and its value is in serving as a catalyst for academics as well as practitioners to rethink and broaden the current paradigm of management accounting in order to be more relevant and useful. It provides a potential new set of tools for management accounting.

This chapter proposes a conceptualization of joyful leadership as a unique leadership style and identifies a future research agenda to further explore the concept. While the concept of joyful leadership appears repeatedly in the nonacademic literature, including in blogs, vlogs, and podcasts, there is limited reference to joyful leadership in the academic literature highlighting a lack of academic rigor around the concept. Joyful leadership is proposed as a unique leadership style with specific patterns of behavior demonstrated by the leader. This research draws on understandings of emotion, positive affect, and leadership in the academic literature to develop a conceptualization of joyful leadership.

The proposed conceptualization is based on an extensive literature review drawing from both the leadership field and the study of emotions including various theoretical perspectives from these diverse fields.

Based on discrete emotion theory a conceptualization of joyful leadership as a unique leadership style is presented, identifying key patterns of behavior associated with joyful leadership including discrete autonomic patterns, actions, nonverbal signals, and identified feelings.

This research outlines a conceptual model to provide an understanding of the concept of joyful leadership as a unique leadership style. It draws on the current study of emotion, positive affect, and leadership and more specifically examines the concept of joyful leadership aligned to discrete emotion theory. This particular theory of emotion, when examined in relation to leadership, provides a basis for the concept of joyful leadership as a leadership style and the basis for its proposed characteristics and outcomes.