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Article
Publication date: 12 March 2018

Martin Robert Greaves and Evelyn Zaugg Hoozemans

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

129

Abstract

Purpose

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

Design/methodology/approach

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.

Findings

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.

Research limitations/implications

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

Practical implications

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

Social implications

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.

Originality/value

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

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Article
Publication date: 9 March 2015

Martin Greaves and Ksenija Topolovec Miklozic

The purpose of this paper was to examine the film-forming behaviour of simple compositions of polyalphaolefin (PAO) containing an oil-soluble polyalkylene glycol (OSP) alone, a…

193

Abstract

Purpose

The purpose of this paper was to examine the film-forming behaviour of simple compositions of polyalphaolefin (PAO) containing an oil-soluble polyalkylene glycol (OSP) alone, a zinc dialkyl dithiophosphate (ZDDP) alone and then combinations of an OSP and ZDDP.

Design/methodology/approach

A Mini-Traction Machine with Spacer Layer Imaging technology was used to evaluate friction and film formation under a specific contact pressure, temperature and slide-to-roll ratio. Electrical contact resistance measurements were used to follow surface film formation.

Findings

The inclusion of an OSP to a PAO showed evidence of friction-reducing behaviour with low friction values over the rubbing cycle but no significant tribo-film build up. When a ZDDP (1 per cent) is added to the PAO, a thick tribo-film forms of about 100 nm. Addition of an OSP (10 per cent) shows this film still forms despite the OSP being a polar and surface-active additive.

Research limitations/implications

The study was conducted under a narrow range of test conditions (e.g. temperature and contact pressure), and future work will focus on friction and film formation across a broader set of conditions.

Practical implications

Despite OSPs being polar and surface-active, they do not interfere with the ZDDP in forming an anti-wear film in a PAO and, therefore, their inherent properties of good deposit control could enhance the performance of modern lubricants.

Originality/value

OSPs offer promising benefits as friction reducers in PAOs. The research also suggests that OSPs do not negate the formation of ZDDP anti-wear tribo-films when in combination in a PAO.

Details

Industrial Lubrication and Tribology, vol. 67 no. 2
Type: Research Article
ISSN: 0036-8792

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Book part
Publication date: 11 August 2006

Elaine Murakami, Stephen Greaves and Tomás Ruiz

Abstract

Details

Travel Survey Methods
Type: Book
ISBN: 978-0-08-044662-2

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Article
Publication date: 1 January 1990

Paul Allen

East Sussex County Council has been invited to allow their TradingStandards Officer to help the European Commission implement the OfficialControl of Foodstuffs Directive. The…

41

Abstract

East Sussex County Council has been invited to allow their Trading Standards Officer to help the European Commission implement the Official Control of Foodstuffs Directive. The author′s views on the Directive are presented.

Details

British Food Journal, vol. 92 no. 1
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 2 March 2012

Nelson Chan and Norman Harker

The purpose of this paper is to re‐visit the problems of taxation consequences of sinking fund in the UK and to look at what is believed to be the only rational reason for using…

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Abstract

Purpose

The purpose of this paper is to re‐visit the problems of taxation consequences of sinking fund in the UK and to look at what is believed to be the only rational reason for using the dual rate adjusted for tax method variant.

Design/methodology/approach

The structure of this paper is: valuing a freehold and a leasehold interest by the single rate gross and net of tax approaches to show the logic that works with freehold valuation interest may not work with leasehold valuation; exploring the tax impacts on sinking fund; resolving the taxation issue of sinking fund; demonstrating the solution to the “double sinking fund problem” by the Greaves method and the single rate net of tax approach; and exploring the future of the dual rate theory.

Findings

The paper confirms that the traditional method is not satisfactory, even after the modifications made by the various methods mentioned above. The single rate net of tax approach is proved to meet all expectations and can be regarded as a more rational approach to the dual rate method.

Practical implications

Valuers of the “UK School” might consider that not only should dual rate valuation be regarded as defunct, but also that the more appropriate approach might be to move to a net of taxation approach.

Originality/value

This paper is the original work of the authors.

Details

Journal of Property Investment & Finance, vol. 30 no. 2
Type: Research Article
ISSN: 1463-578X

Keywords

Abstract

Details

Integrated Land-Use and Transportation Models
Type: Book
ISBN: 978-0-080-44669-1

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Book part
Publication date: 29 January 2013

Stephen Greaves and Richard Ellison

Purpose — Describe the system set-up and processing requirements for a long-duration longitudinal Global Positioning System (GPS)/prompted-recall (PR) survey conducted in Sydney…

Abstract

Purpose — Describe the system set-up and processing requirements for a long-duration longitudinal Global Positioning System (GPS)/prompted-recall (PR) survey conducted in Sydney, Australia and assess reaction and cognition of participants.

Design/methodology/approach — The survey uses data collected using an in-car GPS device within a PR interface accessed over the Internet by participants. Technical requirements, interface design and survey administration of the survey are discussed. This is followed by an assessment of participant burden and cognition by analysing user activity on the PR and comparing participant responses to information inferred from the GPS data.

Findings — New technologies have allowed for increasingly sophisticated data collection efforts but they require substantial resources to translate this into a usable form. This study shows these technologies can be used to conduct long-duration travel studies in a way that is appealing and engaging to participants. However, it was found that responses to the PR are sometimes inconsistent and caution should be drawn in taking PR responses as the ‘ground truth’.

Research limitations/implications — The relatively low participant burden of this study shows long-duration studies are feasible if care is taken to limit the work required by participants. The inconsistency of the responses to the PR suggest future surveys may need to employ mechanisms that are better able to aid participants in accurately completing the survey.

Originality/value — Details the requirements of running a long-duration GPS/PR survey and assesses participant burden and cognition of the survey which are often not reported.

Details

Transport Survey Methods
Type: Book
ISBN: 978-1-78-190288-2

Keywords

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Book part
Publication date: 22 June 2015

Ana Isabel Rodrigues, Antónia Correia, Metin Kozak and Anja Tuohino

Lake tourism is a growing academic sub-field of tourism studies with an emerging body of literature. However, little research attention has been given to lake-destinations’…

Abstract

Lake tourism is a growing academic sub-field of tourism studies with an emerging body of literature. However, little research attention has been given to lake-destinations’ projected or perceived tourism images. Specifically, there has been a scarcity of literature investigating the variables involved in the formation of a lake-destination image. Therefore, this study aims to explore the main attributes that might potentially influence this type of destination, and simultaneously, contribute to conceptualizing and defining lake tourism as recent research area. An explorative study was then conducted in order to generate a set of image variables through the use of textual and photographic data. The results will contribute to characterize potential lake-destinations and to develop a final list of variables specifically related to this type of destination.

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Book part
Publication date: 2 November 2009

Peter R. Stopher

The purpose of this chapter is to provoke thinking about the directions in which the travel survey toolkit should move in the near future based on the author's personal experience…

Abstract

The purpose of this chapter is to provoke thinking about the directions in which the travel survey toolkit should move in the near future based on the author's personal experience and as an outcome of the Travel Survey Methods conference. The chapter begins with a brief historical review that attempts to show some of the major elements of change that have occurred in travel survey methods over the past 40–50 years. A more detailed review is provided about developments over the past 10–15 years. The chapter then explores a number of emerging challenges, including telephone contact of potential respondents, computer-assisted surveys, Internet surveys, mixed-mode surveys, the impacts of language and literacy and the potentials of mobile technologies. Based on this, the chapter then considers future directions that should be pursued. The chapter suggests that it has been changes in survey methodology that have, in the past, sometimes enabled and at other times led to changes in modelling paradigms, and that this may be an appropriate time for travel survey methodology again to enable changes in modelling paradigms. A speculative specification of a new household travel survey that makes use of a number of these developments is then offered. The chapter ends with some concluding remarks that issue a challenge to the travel survey community to think ‘outside the box’ and foster change and improvement in the accuracy and representativeness of travel surveys.

Details

Transport Survey Methods
Type: Book
ISBN: 978-1-84-855844-1

Abstract

Details

Transport Survey Methods
Type: Book
ISBN: 978-1-84-855844-1

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