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Article
Publication date: 4 November 2022

Laiming Yu, Yaqin Fu and Yubing Dong

The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely…

162

Abstract

Purpose

The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely researched and rapidly developed biodegradable copolyester. In a tensile test, we found that the fractured PBAT samples had a heat-driven shape memory effect which piqued our interest, and it will lay a foundation for the application of PBAT in new fields (such as heat shrinkable film).

Design/methodology/approach

The shape memory effect of PBAT and the effect of the thermomechanical condition on its shape memory property were confirmed and systematically investigated by a thermal mechanical analyzer and tensile machine.

Findings

The results showed that the PBAT film had broad shape memory transform temperature and exhibited excellent thermomechanical stability and shape memory properties. The shape memory fixity ratio (Rf) of the PBAT films was increased with the prestrain temperature and prestrain, where the highest Rf exceeded 90%. The shape memory recovery ratio (Rr) of the PBAT films was increased with the shape memory recovery temperature and decreased with the prestrain value, and the highest Rr was almost 100%. Moreover, the PBAT films had high shape memory recovery stress which increased with the prestrain value and decreased with the prestrain temperature, and the highest shape memory recovery stress can reach 7.73 MPa.

Research limitations/implications

The results showed that PBAT had a broad shape memory transform temperature, exhibited excellent thermomechanical stability and shape memory performance, especially for the sample programmed at high temperature and had a larger prestrian, which will provide a reference for the design, processing and application of PBAT-based heat shrinkable film and smart materials.

Originality/value

This study confirmed and systematically investigated the shape memory effect of PBAT and the effect of the thermomechanical condition on the shape memory property of PBAT.

Details

Pigment & Resin Technology, vol. 53 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 2 January 2018

Yubing Dong, Chen Qian, Jian Lu and Yaqin Fu

Epoxy (EP) and polye-caprolactone (PCL) are typical dual-shape memory polymer (DSMP). To get excellent triple-shape memory effect (TSME) polymer composites which are made from EP…

245

Abstract

Purpose

Epoxy (EP) and polye-caprolactone (PCL) are typical dual-shape memory polymer (DSMP). To get excellent triple-shape memory effect (TSME) polymer composites which are made from EP and PCL. Miscible PCL/EP blend composites have been investigated and compared to the TSMEs with electrospun PCL microfiber membranes/EP composites. Clay montmorillonite (MMT)-modified electrospun PCL microfiber membranes were prepared to improve the shape memory fixities of electrospun PCL microfiber membranes/EP composites.

Design/methodology/approach

The morphologies of electrospun PCL microfiber membranes and the cross section of PCL/EP composites were studied using a field emission scanning electron microscope (FE-SEM), and the existence of MMT was confirmed by a transmission electron microscope. Thermal mechanical properties were observed by a differential scanning calorimeter (DSC) and a dynamic thermomechanical analysis machine, and the TSMEs were also determined through dynamic mechanical analysis.

Findings

Results indicate that the TSMEs of electrospun PCL microfiber membranes/EP composites were excellent, whereas the TSMEs of PCL/EP blend composites were poor. The TSMEs of PCL electrospun microfiber membranes/EP composites significantly improved with the addition of the PCL electrospun microfiber modified with moderate MMT.

Research limitations/implications

Adding a moderate content of MMT into the electrospun PCL fibers, could improve the TSME of the PCL fiber membranes/EP composites. This study was to create a simple and effective method that can be applied to improve the performance of other SMP.

Originality/value

A novel triple-shape memory composite were made from dual-shape memory EP and electrospun PCL fiber membranes.

Details

Pigment & Resin Technology, vol. 47 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 11 June 2020

Laiming Yu, Tianqi Zhang, Wenjun Wang, Yubing Dong and Yaqin Fu

This study aims to discuss the effect of carbon fiber on the electric-respone of shape memory epoxy property. Epoxy (EP) is a typical excellent thermosetting shape memory polymer…

346

Abstract

Purpose

This study aims to discuss the effect of carbon fiber on the electric-respone of shape memory epoxy property. Epoxy (EP) is a typical excellent thermosetting shape memory polymer (SMP). To enrich the shape memory epoxy (SMEP) responsive mode, the carbon fiber fabric-reinforced SMEP composites were prepared, and the mechanical properties and the electric- and light-responsive shape memory effect of the composites were investigated and confirmed.

Design/methodology/approach

The carbon fiber fabric/SMEP composites were prepared via a dipping method. The carbon fiber fabric was dipped into the waterborne epoxy emulsion and dried at room temperature and then post-cured in the oven at 120 °C for 2 h. The mechanical properties and the multi-responsive shape memory properties of the composites were tested and confirmed via tensile test instrument, DC electrical source and near-infrared (NIR) laser source control system.

Findings

The carbon fiber fabric/SMEP composites showed excellent electric- and light-responsive shape memory effect.

Research limitations/implications

High performance and multi-responsive shape memory materials have always been the goal of the scientists. Carbon fiber fabric and SMEP both consist of a good reputation in the field of composites, and the combination of both would set a solid foundation for getting a high performance and multi-responsive shape memory effect materials, which will enrich the responsive mode and broaden the application of SMEP.

Originality/value

Multi-responsive SMEP composites were prepared from waterborne epoxy and carbon fiber fabric.

Details

Pigment & Resin Technology, vol. 50 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 17 April 2023

Laiming Yu, Yaqin Fu and Yubing Dong

The purpose of this study is to improve the mechanical property and processing performance and reduce the cost of the polylacticacid/polybutyleneadipate-co-terephthalate(PLA/PBAT…

254

Abstract

Purpose

The purpose of this study is to improve the mechanical property and processing performance and reduce the cost of the polylacticacid/polybutyleneadipate-co-terephthalate(PLA/PBAT) composites, the calcium carbonate (CaCO3) and compatibilizer styrene-maleicanhydride copolymer (SMA-2025) were added to the PLA/PBAT system, and the effect of CaCO3 and SMA-2025 on the morphology, structure, mechanical property, thermal property, thermalstability and shape memory property of the CaCO3/PLA/PBAT composites were studied and discussed.

Design/methodology/approach

The CaCO3/PLA/PBAT shape memory composites were prepared via melt-blending and hot-pressing methods, and the effect of CaCO3 and SMA-2025 on the property of the composites was investigated via scanning electron microscope, universal testing instrument, Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis and DMA, respectively.

Findings

The interface property, mechanical property, thermal stability, shape memory recovery ratios and recovery stresses, and processing performance of the CaCO3/PLA/PBAT shape memory composites were significantly improved by adding of CaCO3 and SMA-2025. Moreover, the CaCO3/PLA/PBAT composites have good blowing film processing performance.

Originality/value

This study will provide a reference for the research, processing and application of the high-performance CaCO3/PLA/PBAT shape memory composites.

Details

Pigment & Resin Technology, vol. 53 no. 5
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 2 April 2019

Ying Cui, Fu Chen, Ali Shiri and Yaqin Fan

Many higher education institutions are investigating the possibility of developing predictive student success models that use different sources of data available to identify…

1925

Abstract

Purpose

Many higher education institutions are investigating the possibility of developing predictive student success models that use different sources of data available to identify students that might be at risk of failing a course or program. The purpose of this paper is to review the methodological components related to the predictive models that have been developed or currently implemented in learning analytics applications in higher education.

Design/methodology/approach

Literature review was completed in three stages. First, the authors conducted searches and collected related full-text documents using various search terms and keywords. Second, they developed inclusion and exclusion criteria to identify the most relevant citations for the purpose of the current review. Third, they reviewed each document from the final compiled bibliography and focused on identifying information that was needed to answer the research questions

Findings

In this review, the authors identify methodological strengths and weaknesses of current predictive learning analytics applications and provide the most up-to-date recommendations on predictive model development, use and evaluation. The review results can inform important future areas of research that could strengthen the development of predictive learning analytics for the purpose of generating valuable feedback to students to help them succeed in higher education.

Originality/value

This review provides an overview of the methodological considerations for researchers and practitioners who are planning to develop or currently in the process of developing predictive student success models in the context of higher education.

Details

Information and Learning Sciences, vol. 120 no. 3/4
Type: Research Article
ISSN: 2398-5348

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Article
Publication date: 3 December 2024

Yaqin Liu, Qian Yu and Jing Li

This study aims to explore the factors influencing the evolution of emerging technology innovation network (ETIN) in combination with the key attributes and life cycle of emerging…

93

Abstract

Purpose

This study aims to explore the factors influencing the evolution of emerging technology innovation network (ETIN) in combination with the key attributes and life cycle of emerging technologies, particularly the impact of multiple knowledge attributes and technology life cycle on the ETIN evolution.

Design/methodology/approach

This study collects 5G patent data and their citation information from the Derwent Innovations Index to construct a 5G technology innovation network (5GIN) as a sample network and conducts an empirical analysis of the 5GIN using the temporal exponential random graph model (TERGM).

Findings

The results indicate that during the 5GIN evolution, the network scale continues to expand and exhibits increasingly significant core-periphery structure, scale-free characteristic, small-world characteristic and community structure. Furthermore, the findings suggest that the multiple knowledge attributes based on the key attributes of emerging technologies, including knowledge novelty, coherence, growth and impact, have a significant positive influence on the ETIN evolution. Meanwhile, the temporal evolution of ETIN is also found to be correlated with the life cycle of emerging technologies.

Originality/value

This study extends the exploration of emerging technology research from a complex network perspective, providing a more realistic explanatory framework for the factors influencing ETIN evolution. It further highlights the important role that multiple knowledge attributes and the technology life cycle play within this framework.

Details

Journal of Knowledge Management, vol. 29 no. 2
Type: Research Article
ISSN: 1367-3270

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Article
Publication date: 16 April 2024

Sha Zhou, Yaqin Su, Muhammad Aamir Shahzad and Zhengchi Liu

The integration of social media and e-commerce has resulted in a rising phenomenon among individual content providers (ICPs), who used to offer free content, to provide consumers…

235

Abstract

Purpose

The integration of social media and e-commerce has resulted in a rising phenomenon among individual content providers (ICPs), who used to offer free content, to provide consumers with paid content, such as online courses, Q&As or consultations. Despite the prevalence of ICPs’ content monetization, empirical research has rarely studied its underlying mechanism. This paper examines how the characteristics of free content contributed by ICPs on social media platforms influence their paid content sales, focusing on the perspective of human brand.

Design/methodology/approach

The empirical setting is an online knowledge exchange platform, where users are allowed to provide free content (e.g. answers) on the social media platform and launch paid content (e.g. lectures) on the e-commerce platform. A machine learning technique is employed to construct measures for the characteristics of free content, and fixed-effects estimation is presented to confirm which factors have a significant influence on the sales of paid content.

Findings

The empirical results show that the quality, diversity and expertness of free content have a significant positive impact on the sales of the ICP-paid content, with the brand popularity of ICP playing a mediating role.

Originality/value

This study is the first attempt to demystify the relationship between content contribution and ICPs’ content monetization from the perspective of human brand. The findings validate the effectiveness of the “Selling by Contribution” strategy and provide valuable insights for ICPs and social media platforms.

Details

Internet Research, vol. 35 no. 1
Type: Research Article
ISSN: 1066-2243

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Article
Publication date: 19 June 2023

Yaqin Yuan, Hongying Tan and Linlin Liu

This study aims to investigate the impact of digital transformation on supply chain resilience. Additionally, the paper examines the mediating effect of supply chain process…

3078

Abstract

Purpose

This study aims to investigate the impact of digital transformation on supply chain resilience. Additionally, the paper examines the mediating effect of supply chain process integration as well as the moderating effect of environmental uncertainty in the relationship between digital transformation and supply chain resilience.

Design/methodology/approach

Drawing on digital empowerment theory, this study proposes a theoretical model. Using survey data collected from 216 enterprises in China, the study employs structural equation modeling to validate the theoretical model.

Findings

The results reveal that digital transformation has a significant impact on supply chain resilience. Three dimensions of supply chain process integration, namely, information flow integration, physical flow integration, and financial flow integration mediate the relationship between digital transformation and supply chain resilience. In addition, environmental uncertainty including market uncertainty and technology uncertainty positively moderates the relationship between digital transformation and supply chain resilience.

Originality/value

First, this paper provides empirical evidence on both the direct and indirect effects of digital transformation on supply chain resilience. Second, this paper enriches the understanding of how supply chain integration impacts supply chain resilience in the digital transformation era by adopting a more granular perspective of process integration rather than broad external and internal integrations. Furthermore, this paper extends the knowledge of the role of external environment in digital transformation and supply chain risk management by examining the moderating effects of market uncertainty and technology uncertainty.

Details

Journal of Enterprise Information Management, vol. 37 no. 2
Type: Research Article
ISSN: 1741-0398

Keywords

Available. Open Access. Open Access
Article
Publication date: 2 May 2022

Yaqin Zou, Xuemei Jiang, Caiyun Wen and Yang Li

After the Collective Forest Tenure Reform (CFTR) in China, the enthusiasm of farmers for forestry management is stimulated. However, the forest tenure security varies among…

657

Abstract

Purpose

After the Collective Forest Tenure Reform (CFTR) in China, the enthusiasm of farmers for forestry management is stimulated. However, the forest tenure security varies among farmers, making the research conclusions of its impact on forestry management efficiency inconsistent. Based on the survey data of 1,627 households from the collective forest regions in 6 provinces of China in 2017, this paper not only discusses the differences of farmers' forestry management efficiency after the reform, but also further explores the heterogeneous impact of forest tenure security on forestry management efficiency in combination with different forest management types.

Design/methodology/approach

This study employed the stochastic frontier production function model to measure the forestry management efficiency of farmers. Then, Tobit models were used to discuss the influencing factors of farmers' forestry management efficiency.

Findings

The results demonstrate that the improvement of farmers' forest tenure security can effectively improve forestry management efficiency, but the effect is affected by forest management types. For farmers who manage economic forests and non-timber forests, safe tenure promotes the forestry management efficiency; while for those who manage ecological public welfare forests, tenure security plays an opposite role.

Originality/value

Therefore, satisfying farmers' differentiated demands for forest tenure according to forest management types to improve forest tenure security and further refining supporting policies of collective forestry reform is of great significance to improve the efficiency of farmers' forestry management in collective forest regions.

Details

Forestry Economics Review, vol. 4 no. 1
Type: Research Article
ISSN: 2631-3030

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Book part
Publication date: 9 September 2024

Reham ElMorally

Abstract

Details

Recovering Women's Voices: Islam, Citizenship, and Patriarchy in Egypt
Type: Book
ISBN: 978-1-83608-249-1

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