Search results

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 paper aims to modify carbon nanotubes with oleic acid, and to study the tribological properties of castor oil with modified carbon nanotubes additives. The proper additives are sought for the future engineering application of castor oil.

Tribological properties of the castor oils mixed with the modified carbon nanotubes of four mass percentages were investigated using a four-ball testing rig. Coefficient of friction and wear scar diameter were obtained in each test, and the mechanism of modified carbon nanotubes and castor oil was discussed.

The results indicated that modified carbon nanotubes had better dispersion in castor oil. Coefficient of friction first increased, then decreased and finally grew stable with the time, and wear scar diameter of steel surface functioned as a first reduced then increased change with the additive mass percentage of modified carbon nanotubes. The minimum of average coefficient of friction and wear scar diameter occurred at 0.02 Wt.% modified carbon nanotubes.

A small amount of modified carbon nanotubes could improve properties of the castor oil, and the mixed castor oil with 0.02 Wt.% modified carbon nanotubes would be most possibly used in engineering applications.

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.

This paper aims to examine the role of different polyalkylene glycol architectures in improving the hydrolytic stability of natural and synthetic esters.

Hydrolytic stability measurements were conducted using a modified ASTM D2619 test method in which several polyalkylene glycol chemistries were examined at concentrations of up to 10 per cent in a selection of esters.

The inclusion of triblock copolymers derived from ethylene oxide (EO) and 1,2-propylene oxide (PO) and with an EO content of about 30 per cent produced significant improvements in the hydrolytic stability of natural and synthetic esters. Stability improved with increased concentration of the triblock.

The study did not evaluate the vast array of polyalkylene glycol structures that can be derived from other higher alkylene oxides.

Improving the hydrolytic stability of esters can offer the possibility of creating longer life environmentally acceptable lubricants (EALs).

This discovery should allow longer life EALs to be designed thereby using less raw materials over a determined period. It may also allow more replacement of conventional hydrocarbon lubricants.

Triblock copolymers are rarely used in lubricants. Their use as components of ester-based EALs is new.

Evidence suggests that retail investors who invest in individual stocks are, in the long run, largely outperformed by market indexes such as the MSCI World. While some turn to exchange traded funds (ETFs) to invest in such market indexes, few migrate completely to ETFs. This study aims to shed light on the rationale behind retail investors' partial and complete migration from stocks to ETFs.

Drawing from the pull-push-mooring framework, a qualitative study (N = 21) informs a quantitative study (N = 282) by following established mixed methods guidelines. This study develops propositions for partial and complete migration intention to ETFs.

Results reveal that perceived investment possibilities, perceived risk reduction, perceived administrative effort, perceived expensiveness and monetary loss costs influence the migration from stocks to ETFs. This study shows that three configurations of perceptions result in partial migration intention and one configuration results in complete migration intention.

This study explains why some migrate partially from stocks to ETFs and others migrate completely. Findings show that both migration behaviors are subject to the same perceptions, but the configurations that form the behaviors are different. While only some identified perceptions must be present for a partial migration, all of them must be present for a complete migration, as it requires retail investors to sell their stocks and accept the costs incurred to invest in ETFs instead.

This paper aims to posit the central argument that traditional media of old presented a clear, ordered world of communication management for organisations to extol their corporate social responsibility (CSR) credentials. In contrast to this, new Web 2.0 social media is increasingly being used by activists and hactivists to challenge corporate communication CSR messages and does so by highlighting instances and examples of corporate social irresponsibility (CSI) (Jones et al., 2009; Tench et al., 2012).

The paper reports on research data from the European Communication Monitor, 2010, 2011 and 2012 (www.communicationmonitor.eu/) and draws on work already published in this area (Tench et al., 2009; Verhoeven et al., 2012; Zerfass et al., 2010, 2011) to illustrate the unruly, unregulated Web 2.0 social media communication landscape in Europe. A range of literature is drawn on to provide the theoretical context for an exploration of issues that surround social media.

In late modernity (Giddens, 1990), communication comes in many guises. Social media is one guise and it has re-shaped as well as transformed the nature of communications and the relationship between organisations and their stakeholders.

Communicating CSR in the Wild West of social media requires diplomatic and political nous, as well as awareness and knowledge of the dangers and pitfalls of CSI. The data reported on in this paper well illustrate the above points and set out scenarios for future development of corporate communication of CSR through and with social media.

This chapter explores knowledge practices around the subject of capital punishment. Capital sentencing jurisprudence and certain strands of academic scholarship on the death penalty have certain resonances with recent developments in reflexive cultural anthropology. Using the notion of productive unraveling, this chapter seeks to reinforce relations between these various knowledge practices by conceiving of them as situated on the same ground, already interwoven with one another. This chapter presents itself as both an example of and a call for the development of interconnections between these various kinds of expert knowledges concerning the death penalty.

The latest information from the magazine chemist is extremely valuable. He has dealt with milk‐adulteration and how it is done. His advice, if followed, might, however, speedily bring the manipulating dealer before a magistrate, since the learned writer's recipe is to take a milk having a specific gravity of 1030, and skim it until the gravity is raised to 1036; then add 20 per cent. of water, so that the gravity may be reduced to 1030, and the thing is done. The advice to serve as “fresh from the cow,” preferably in a well‐battered milk‐measure, might perhaps have been added to this analytical gem.

The purpose of this paper is to illustrate a service quality framework that enhances service delivery in clinical laboratories by gauging medical practitioner satisfaction and by providing avenues for continuous improvement.

The case study method has been used for conducting the exploratory study, with focus on the Mauritian public clinical laboratory. A structured questionnaire based on the SERVQUAL service quality model was used for data collection, analysis and for the development of the service quality framework.

The study confirms the pertinence of the following service quality dimensions within the context of clinical laboratories: tangibility, reliability, responsiveness, turnaround time, technology, test reports, communication and laboratory staff attitude and behaviour.

The service quality framework developed, termed LabSERV, is vital for clinical laboratories in the search for improving service delivery to medical practitioners.

This is a pioneering work carried out in the clinical laboratory sector in Mauritius. Medical practitioner expectations and perceptions have been simultaneously considered to generate a novel service quality framework for clinical laboratories.

Family business

This case study is relevant for undergraduate and post-graduate degrees, specifically in the field of entrepreneurship. This case can be applied in the family business and entrepreneurship module.

This case highlights the issue of succession planning in a family business. It describes the problem faced by the founder of a security service company, Kurniawan Security Services Sdn Bhd., in handing over his business to his sons. The case depicts the occurrence of conflicts as one of the common problems in running a family business which, in the end, may affect the perpetuity of the business concerns.

Upon completion of the case analysis, students should be able to explain the concept of entrepreneurship in the context of a family business, discuss the issue of succession planning commonly associated with running a family business, analyse critically the nature of conflicts that may occur in a family business and suggest how the problem(s) can be attempted to be solved from within the business management perspectives.

Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.