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Article
Publication date: 7 September 2012

V. Marchante Rodríguez, F.M. Martínez‐Verdú, M.I. Beltrán Rico and A. Marcilla Gomis

This research deals with a new kind of nanopigment, obtained from the combination of organic dyes and layered nanoclays, that the authors call nanoclay‐colorant pigment (NCP)…

221

Abstract

Purpose

This research deals with a new kind of nanopigment, obtained from the combination of organic dyes and layered nanoclays, that the authors call nanoclay‐colorant pigment (NCP). Whilst they have already been employed in inks and coatings, to date these nanopigments have not been used as pigments for polymers. The existing lack of knowledge surrounding them must be redressed in order to bridge the gap between current academic studies and commercial exploitation. Therefore, the main purpose of this paper is to examine the hitherto unknown aspects of the NCP, which relate specifically to their applicability as a new type of colorant for polymers.

Design/methodology/approach

A blue NCP has been prepared at the laboratory according to the patented method of synthesis (patent WO0104216), using methylene blue and montmorillonite nanoclay. It has then been applied to a thermoplastic polymer (linear low‐density polyethylene – LLDPE) to obtain a coloured sample. Furthermore, samples with the same polymer but using conventional blue colorants have been prepared under the same processing conditions. The mechanical, thermal and colorimetric properties of these materials have been compared.

Findings

The thermal stability of the sample coloured with NCP is reduced to some extent, while the mechanical strength is slightly increased. Moreover, this sample has better colour performance than the conventionally pigmented samples.

Originality/value

In this paper, a blue NCP has been synthesised and successfully employed with polyethylene and the obtained sample shows better colour performance than polyethylene with conventional pigments.

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Article
Publication date: 25 October 2019

Beltran Roca, Eva Bermúdez-Figueroa and Francisco Estepa-Maestre

The purpose of this paper is to examine the potential of life story for the teaching of sociology to Social Work students. It contains the results of a teaching experiment in…

253

Abstract

Purpose

The purpose of this paper is to examine the potential of life story for the teaching of sociology to Social Work students. It contains the results of a teaching experiment in higher education which aims to foster sociological imagination among students.

Design/methodology/approach

The study employs a mixed methodology. The quantitative data came from a survey handed out to the students with closed and open questions. The qualitative information came from the contents of class exercises in which the students had to connect the theoretical contents of the course of sociology with the biographical narratives of different research subjects.

Findings

The results reflect student satisfaction or appreciation regarding the use of the life story as a teaching resource, as well as a successful acquisition of sociological skills and knowledge, such as critical thinking, micro-macro connection and the interplay between structure and agency.

Practical implications

Life story and narrative methods should be employed in post-secondary education as teaching instruments.

Originality/value

The study contributes to expand the reflection on narrative techniques as a pedagogical tool. The paper provides several examples of class exercises with biographical narratives that have demonstrated to be successful for teaching sociology in higher education.

Details

Journal of Applied Research in Higher Education, vol. 12 no. 5
Type: Research Article
ISSN: 2050-7003

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Article
Publication date: 9 May 2019

Z.H.Z. Abidin, N.S.A. Manah, A.N. Hadi, N.S. Saugi, F.A. Fuad, N.A. Mazni, H.C. Hassan, M.A. Careem and A.K. Arof

This paper aims to focus on a comparison study of the visible stability of natural blue dye consisting anthocyanin molecules extracted from Clitoria ternatea in coating films.

176

Abstract

Purpose

This paper aims to focus on a comparison study of the visible stability of natural blue dye consisting anthocyanin molecules extracted from Clitoria ternatea in coating films.

Design/methodology/approach

The coating films were prepared by mixing the blue dye with poly(acrylamide-co-acrylic acid) in three different weight ratios. Samples were coded as 10PBA, 15PBA and 20PBA, where PBA is the abbreviation for poly acrylamide-co-acrylic acid, blue dyes and anthocyanin. The number at the beginning of each code represents the weight percentage of poly(acrylamide-co-acrylic acid) to natural blue dye. The mixtures were applied on separate glass substrates to form coating films. Another set of samples were prepared for the comparison study with a commercial acrylic clear coat (cc) applied on the surface of the 10PBA, 15PBA and 20PBA coating films. These coating films were coded 10PBAcc, 15PBAcc and 20PBAcc. The purpose of the clear coat is to observe how it affects the colour stability of the blue coating films with respect to time. All samples were exposed to the ultraviolet (UV) source, an 18 W Philips TL-D 18w/830 UV fluorescent lamp. The UV lamp was placed 15 cm above the surface of the samples for 35 days. The colour of the coatings was measured using CIE L*a*b* colour space coordinate.

Findings

The results obtained show 10PBA and 10PBAcc have the highest colour stability after 35 days of exposure to UV light. The reflectivity of the coating films was also measured during exposure to UV lamp. Reflectivity measurements also showed that 10PBA and 10PBAcc coating films had the highest reflective stabilities.

Research limitations/implications

The potential of using natural blue dye consisting anthocyanin in coating film to obtain high colour stability.

Practical implications

The coating film developed in this work is suitable to be applied on glass substrates.

Originality/value

The application of anthocyanin dye extracted from the Clitoria ternatea L. as a colourant in coating films

Details

Pigment & Resin Technology, vol. 48 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 15 November 2022

Pablo Zapico, Fernando Peña, Gonzalo Valiño, José Carlos Rico, Víctor Meana and Sabino Mateos

The lack of geometric and dimensional accuracy of parts produced by additive manufacturing (AM) is directly related to the machine, material and process used. This paper aims to…

167

Abstract

Purpose

The lack of geometric and dimensional accuracy of parts produced by additive manufacturing (AM) is directly related to the machine, material and process used. This paper aims to propose a method for the analysis and compensation of machine-related geometric errors applicable to any AM machine, regardless of the manufacturing process and technology used.

Design/methodology/approach

For this purpose, an error calculation model inspired by those used in computerized numerical control machines and coordinate measuring machines was developed. The error functions of the model were determined from the position deviations of a set of virtual points that are not sensitive to material and process errors. These points were obtained from the measurement of an ad hoc designed and manufactured master artefact. To validate the model, off-line compensation was applied to both the original designed artefact and an example part.

Findings

The geometric deviations in both cases were significantly smaller than those found before applying the geometric compensation. Dimensional enhancements were also achieved on the example part by using a correction parameter available in the three-dimensional printing software, whose value was adjusted from the measurement of the geometrically compensated master artefact.

Research limitations/implications

The errors that persist in the part derive from both material and process. Compensation for these type of errors requires a detailed analysis of the influencing parameters, which will be the subject of future research.

Originality/value

The use of the virtual-point-based error model increases the quality of additively manufactured parts and can be used in any AM system.

Details

Rapid Prototyping Journal, vol. 29 no. 4
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 2 January 2024

Fernando Peña, José Carlos Rico, Pablo Zapico, Gonzalo Valiño and Sabino Mateos

The purpose of this paper is to provide a new procedure for in-plane compensation of geometric errors that often appear in the layers deposited by an additive manufacturing (AM…

156

Abstract

Purpose

The purpose of this paper is to provide a new procedure for in-plane compensation of geometric errors that often appear in the layers deposited by an additive manufacturing (AM) process when building a part, regardless of the complexity of the layer geometry.

Design/methodology/approach

The procedure is based on comparing the real layer contours to the nominal ones extracted from the STL model of the part. Considering alignment and form deviations, the compensation algorithm generates new compensated contours that match the nominal ones as closely as possible. To assess the compensation effectiveness, two case studies were analysed. In the first case, the parts were not manufactured, but the distortions were simulated using a predictive model. In the second example, the test part was actually manufactured, and the distortions were measured on a coordinate measuring machine.

Findings

The geometric deviations detected in both case studies, as evaluated by various quality indicators, reduced significantly after applying the compensation procedure, meaning that the compensated and nominal contours were better matched both in shape and size.

Research limitations/implications

Although large contours showed deviations close to zero, dimensional overcompensation was observed when applied to small contours. The compensation procedure could be enhanced if the applied compensation factor took into account the contour size of the analysed layer and other geometric parameters that could have an influence.

Originality/value

The presented method of compensation is applicable to layers of any shape obtained in any AM process.

Details

Rapid Prototyping Journal, vol. 30 no. 3
Type: Research Article
ISSN: 1355-2546

Keywords

Available. Content available
Book part
Publication date: 13 November 2017

Nohora García

Abstract

Details

Understanding Mattessich and Ijiri: A Study of Accounting Thought
Type: Book
ISBN: 978-1-78714-841-3

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Book part
Publication date: 19 October 2012

Antonio Aledo, Jens Kr. Steen Jacobsen and Leif Selstad

The Spanish region commercially branded as Costa Blanca has long been a popular destination for millions of holidaymakers from both northern Europe and Spain itself (Gaviria

Abstract

The Spanish region commercially branded as Costa Blanca has long been a popular destination for millions of holidaymakers from both northern Europe and Spain itself (Gaviria Labarta, 1974; Moreno Garrido, 2007). However, from the 1960s onward, these Mediterranean shores have also attracted thousands of people from northern Europe for other purposes, some as more or less permanent residents, and others as seasonal peripatetic visitors, traveling back and forth between their first, second or third homes (Aledo, 2008). In many ways, the increase in second home visits and long-term stays in areas such as Mediterranean Spain parallels well-known developments of seasonal and full-time retirement and other migration in North America to what has been termed the Sunbelt states (Mings & McHugh, 1995). The situation in Europe, however, is more complex, due, for instance, to the crossing of national borders, a variety of spoken languages, and possibly also for greater cultural differences. Certain parts of such flows are related to perceptions of diminishing distances and to the progress of internationalization processes in societies in general, where tourism and other long-distance mobilities are not only an outcome, but also a crucial catalyst.

Details

Culture and Society in Tourism Contexts
Type: Book
ISBN: 978-0-85724-683-7

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Article
Publication date: 10 January 2020

Maria Santos Corrada, Jose A. Flecha and Evelyn Lopez

The purpose of this paper is to examine the use of social media and its impact on information search, communication with a company, and purchase and re-purchases of products and…

2542

Abstract

Purpose

The purpose of this paper is to examine the use of social media and its impact on information search, communication with a company, and purchase and re-purchases of products and services. Using use and gratification theory as a starting point, it also examines the impact of satisfaction of use of social media in the process of purchasing and re-purchasing products and services.

Design/methodology/approach

An online survey was conducted with 444 participants, and the data were analyzed using the partial least squares structural equation modeling technique to observe the effects between the variables of social media use, search information, communication with the company, purchase, re-purchase and satisfaction of use of social media.

Findings

The results reflect how the use of social media generates significant rewards that significantly impact the search for information and the communication with the company. The data also show how communication with the company has an impact on the purchase and re-purchase of products and services. Finally, it was empirically confirmed that the gratification received by users through social media use impacts satisfaction with social media use.

Originality/value

The results contribute to how social media impacts alternative evaluations through the gratification of user needs, resulting in motives and behaviors leading to the purchase of goods and services, as established by Use and Gratification Theory. In its contributions to the Academy, Use and Gratification Theory (U&G) explains why individuals use and share information using social media. First, it justifies the purchase and re-purchase of products and services due to user satisfaction according to users’ experience using social media. Second, it presents a vision of how the use of social media is a significantly important result in the gratification of consumer needs.

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Article
Publication date: 10 October 2018

Ali Khoshkhoo, Andres L. Carrano and David M. Blersch

The purpose of this paper is to elucidate the effect of part thickness and build orientation upon the type and magnitude of distortion in material jetting processes.

428

Abstract

Purpose

The purpose of this paper is to elucidate the effect of part thickness and build orientation upon the type and magnitude of distortion in material jetting processes.

Design/methodology/approach

Specimens with high (10:1) aspect ratio were printed in two orientations (XY and YX) and three thickness values (1, 3 and 6 mm) and scanned with a white-light profilometer to quantify distortion.

Findings

The results of this paper indicate that 1-mm thick specimens always distorted following a wavy edge type, while thicker specimens (3- and 6-mm) always distorted following a reverse coil set. The factor thickness, when measured with the indices height of the highest peak (H) and profile radius (R), was shown to be statistically significant, with 3-mm specimens experiencing distortions of 57 and 51 per cent, respectively, more severe than those in 6-mm specimens. The thickness effect is attributed to the percentage of build layers that receive maximum energy exposure (61-72 per cent in 1-mm, 87-91 per cent in 3-mm and 93-95 per cent in 6-mm specimens). With respect to the thinner 1-mm specimens, the factor orientation was found to be statistically significant with distortion 114 per cent less severe in the YX orientation when measured by the H index.

Originality/value

This paper provides the first known description of build orientation and part thickness effects on dimensional distortion as a pervasive consequence of the curing process in photopolymerization and explores one of the most common defects encountered in additive manufacturing. In addition to the characterization of the type and magnitude of distortion, the contributions of this paper also include establishing the foundation for design guidelines aiming at minimizing distortion in material jetting.

Details

Rapid Prototyping Journal, vol. 24 no. 9
Type: Research Article
ISSN: 1355-2546

Keywords

Available. Open Access. Open Access
Article
Publication date: 5 May 2020

Alice Stiletto, Elisa Giampietri and Samuele Trestini

The present study aims at analysing consumer preferences for the pomegranate fruit, focussing on the effect of ready-to-eat format (i.e. packaged arils) on the purchasing choice…

1712

Abstract

Purpose

The present study aims at analysing consumer preferences for the pomegranate fruit, focussing on the effect of ready-to-eat format (i.e. packaged arils) on the purchasing choice, together with several products’ attributes as the origin, the packaging typology and the price.

Design/methodology/approach

The paper presents a choice experiment (CE) among 626 Italian consumers from Veneto region through an online survey. The study estimates both a conditional logit (CL) and a latent class logit model (LCM).

Findings

By segmenting the sample based on the heterogeneous preferences of consumers, it can distinguish “eco-friendly consumers”, “time-saving lovers”, “nationalists” and “price sensitive” subjects. Interestingly, the marginal willingness to pay for ready-to-eat arils is positive for the “time-saving lovers” that are mainly young consumers. The Italian origin has always a positive effect on the choice, whereas a negative effect is found for the price. Finally, the eco-friendly package has both a negative and a positive effect.

Research limitations/implications

The sample of this study is not representative of the population and the CE has a hypothetical nature. It follows that further research will link the economic analysis to a consumer test on a more representative sample.

Practical implications

This study can be useful for the pomegranate producers and the industry because it provides original evidence that could drive their business and marketing strategies, for instance, the preference for ready-to-eat arils.

Originality/value

This study is one of the first seeking to determine the factors that affect consumers' preferences for pomegranate arils.

Details

British Food Journal, vol. 122 no. 12
Type: Research Article
ISSN: 0007-070X

Keywords

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