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21 – 30 of over 6000
Article
Publication date: 17 November 2022

Jinxia Jiang, Haojie Zhao and Yan Zhang

This study aims to investigate the two-dimensional magnetohydrodynamic flow and heat transfer of a fractional Maxwell nanofluid between inclined cylinders with variable thickness…

Abstract

Purpose

This study aims to investigate the two-dimensional magnetohydrodynamic flow and heat transfer of a fractional Maxwell nanofluid between inclined cylinders with variable thickness. Considering the cylindrical coordinate system, the constitutive relation of the fractional viscoelastic fluid and the fractional dual-phase-lag (DPL) heat conduction model, the boundary layer governing equations are first formulated and derived.

Design/methodology/approach

The newly developed finite difference scheme combined with the L1 algorithm is used to numerically solve nonlinear fractional differential equations. Furthermore, the effectiveness of the algorithm is verified by a numerical example.

Findings

Based on numerical analysis, the effects of parameters on velocity and temperature are revealed. Specifically, the velocity decreases with the increase of the fractional derivative parameter α owing to memory characteristics. The temperature increase with the increase of fractional derivative parameter ß due to a decrease in thermal resistance. From a physical perspective, the phase lag of the heat flux vector and temperature gradients τq and τT exhibit opposite trends to the temperature. The ratio τT/τq plays an important role in controlling different heat conduction behaviors. Increasing the inclination angle θ, the types and volume fractions of nanoparticles Φ can increase velocity and temperature, respectively.

Originality/value

Fractional Maxwell nanofluid flows from a fixed-thickness pipe to an inclined variable-thickness pipe, and the fractional DPL heat conduction model based on materials is considered, which provides a basis for the safe and efficient transportation of high-viscosity and condensable fluids in industrial production.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 5
Type: Research Article
ISSN: 0961-5539

Keywords

Book part
Publication date: 25 May 2021

M. Ozan Yildirim

Introduction: Financial development has a direct impact on the housing market by facilitating access to credit. The increase in housing loans resulting from the relaxation of the…

Abstract

Introduction: Financial development has a direct impact on the housing market by facilitating access to credit. The increase in housing loans resulting from the relaxation of the credit constraint causes an increase in housing demand and house prices. Purpose: This study aims to examine the relationship between financial development and house prices in Turkey, using the variables: the domestic credit to the private sector and total housing and consumer credits. Methodology: To determine any long-run relationship between financial development and house prices, the autoregressive distributed lag methods are used, covering the selected variables such as real GDP, inflation, mortgage interest rate, and stock price from 2010Q1 to 2020Q2. Findings: The study’s findings show that both variables representing financial development have a statistically significant and substantial positive effect on house prices. Besides, the selected macroeconomic variables have the theoretically expected impact on house prices.

Details

Contemporary Issues in Social Science
Type: Book
ISBN: 978-1-80043-931-3

Keywords

Book part
Publication date: 1 March 2021

Fiona Keegan, Elaine L. Ritch and Noreen Siddiqui

By the end of this chapter, you should be able to demonstrate an understanding of:The way in which consumers use mobile devices to engage with fashion retailers online.What…

Abstract

By the end of this chapter, you should be able to demonstrate an understanding of:

The way in which consumers use mobile devices to engage with fashion retailers online.

What external and internal stimuli can be used to engage with consumers and encourage online interaction?

The lens in with the Stimulus–Organism–Response (SOR) model is applied to understand consumer behaviour.

How marketing can used both to trigger consumption activities and to encourage more sustainable behaviours?

Details

New Perspectives on Critical Marketing and Consumer Society
Type: Book
ISBN: 978-1-83909-554-2

Keywords

Article
Publication date: 28 June 2021

Abdullah Alkraiji and Nisreen Ameen

This study examines the effect of multidimensional constructs on citizen loyalty to e-government services. More specifically, it examines the effects of service quality, trust and…

2394

Abstract

Purpose

This study examines the effect of multidimensional constructs on citizen loyalty to e-government services. More specifically, it examines the effects of service quality, trust and satisfaction on loyalty to these services.

Design/methodology/approach

The data were collected via a questionnaire that was completed by 780 foundation-year students in government universities in Saudi Arabia. The students who participated in the study had used a unified system provided by the Ministry of Education in Saudi Arabia for university admission. The data were analysed using structural equation modelling.

Findings

The key findings revealed that the factors service quality, trust in government, trust in e-government services and citizen satisfaction play a significant role in developing citizen loyalty to e-government services. Trust in government has the strongest direct effect on citizen loyalty to e-government services, and service quality has the strongest total effect on citizen loyalty. In contrast, citizen satisfaction has the least significant influence on citizen loyalty to e-government services.

Originality/value

This study proposes a new model for citizen loyalty to e-government services that combines the service quality model and trust theory. In addition, this study is among the first to categorise trust into three factors – trust in government, trust in e-government and disposition to trust – and integrate them into a model. Furthermore, the study reveals the roles of satisfaction and service quality in developing citizen loyalty. The findings of this study fill a gap in knowledge on citizen trust in, satisfaction with and loyalty to e-government services.

Details

Information Technology & People, vol. 35 no. 4
Type: Research Article
ISSN: 0959-3845

Keywords

Article
Publication date: 22 August 2019

Yuanpeng Cheng, Yu Bai, Shanfa Tang, Dukui Zheng, Zili Li and JianGuo Liu

The purpose of this paper is to investigate the corrosion behavior of X65 steel in the CO2-saturated oil/water environment using mass loss method, potentiodynamic polarization…

Abstract

Purpose

The purpose of this paper is to investigate the corrosion behavior of X65 steel in the CO2-saturated oil/water environment using mass loss method, potentiodynamic polarization technique and characterization of the corroded surface techniques.

Design/methodology/approach

The weight loss analysis, electrochemical study and surface investigation were carried out on X65 steel that had been immersed in the CO2/oil/water corrosive medium to understand the corrosion behavior of gathering and transportation pipeline steel. The weight loss tests were carried out in a 3 L autoclave, and effects of water cut and temperature on the CO2 corrosion rate of X65 steel were studied. Electrochemical studies were carried out in a three-electrode electrochemical cell with the test temperature was 60°C, and the CO2 partial pressure was 1 atm by recording open circuit potential/time and potentiodynamic polarization characteristics. The surface and cross-sectional morphologies of corrosion product scales were characterized using scanning electron microscopy. The phases of corrosion product scales were investigated using x-ray diffraction.

Findings

The results showed that due to the wetting and adsorption of crude oil, the corrosion morphology of X65 steel changed under different water cuts. When the water cut of crude oil was 40-50 per cent, uniform corrosion occurred on the steel surface, accompanied by local pitting. While the water cut was 70-80 per cent, the resulting corrosion product scales were thick, loose and partial shedding caused platform corrosion. When the water cut was 90 per cent, the damaged area of platform corrosion was enlarged. Crude oil can hinder the corrosion scales from being dissolved by the corrosive medium, and change dimension and accumulation pattern of the crystal grain, thickness and structure of the corrosion scales. Under the corrosion inhibition effect of crude oil, the temperature sensitive point of X65 steel corrosion process moved to low temperature, appeared at about 50°C, lower corrosion rate interval was broadened and the corrosion resistance of X65 steel was enhanced.

Originality/value

The results can be helpful in selecting the applicable corrosion inhibitors and targeted anti-corrosion measures for CO2-saturated oil/water corrosive environment.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Book part
Publication date: 14 December 2023

Nausheen Bibi Jaffur, Pratima Jeetah and Gopalakrishnan Kumar

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental…

Abstract

The increasing accumulation of synthetic plastic waste in oceans and landfills, along with the depletion of non-renewable fossil-based resources, has sparked environmental concerns and prompted the search for environmentally friendly alternatives. Biodegradable plastics derived from lignocellulosic materials are emerging as substitutes for synthetic plastics, offering significant potential to reduce landfill stress and minimise environmental impacts. This study highlights a sustainable and cost-effective solution by utilising agricultural residues and invasive plant materials as carbon substrates for the production of biopolymers, particularly polyhydroxybutyrate (PHB), through microbiological processes. Locally sourced residual materials were preferred to reduce transportation costs and ensure accessibility. The selection of suitable residue streams was based on various criteria, including strength properties, cellulose content, low ash and lignin content, affordability, non-toxicity, biocompatibility, shelf-life, mechanical and physical properties, short maturation period, antibacterial properties and compatibility with global food security. Life cycle assessments confirm that PHB dramatically lowers CO2 emissions compared to traditional plastics, while the growing use of lignocellulosic biomass in biopolymeric applications offers renewable and readily available resources. Governments worldwide are increasingly inclined to develop comprehensive bioeconomy policies and specialised bioplastics initiatives, driven by customer acceptability and the rising demand for environmentally friendly solutions. The implications of climate change, price volatility in fossil materials, and the imperative to reduce dependence on fossil resources further contribute to the desirability of biopolymers. The study involves fermentation, turbidity measurements, extraction and purification of PHB, and the manufacturing and testing of composite biopolymers using various physical, mechanical and chemical tests.

Details

Innovation, Social Responsibility and Sustainability
Type: Book
ISBN: 978-1-83797-462-7

Keywords

Article
Publication date: 4 February 2014

Huan Chen, Junhui Jiang, Tianhui Ren, Lei Zheng and Yidong Zhao

In order to meet the requests of exploring environmental-friendly and multifunctional lubricant additives, some novel dimercaptothiadiazole derivatives containing hydroxyl are…

Abstract

Purpose

In order to meet the requests of exploring environmental-friendly and multifunctional lubricant additives, some novel dimercaptothiadiazole derivatives containing hydroxyl are prepared and used as antiwear (AW) and extreme-pressure (EP) additives in biodegradable lithium grease. The paper aims to discuss these issues.

Design/methodology/approach

The tribological performances of the grease samples containing these derivatives are evaluated by using a four-ball tester. X-ray absorption near edge structure (XANES) spectroscopy is used to analyze the chemistry of tribofilms under AW/EP regime, and thermal films are also considered for comparison.

Findings

The tribological tests show that these derivatives are all effective in reducing wear, especially at lower additive concentrations, but they are basically failed in reducing friction. They are also helpful in improving the EP characteristic of the base grease. The thermal films generated by these derivatives are composed of adsorbed organic sulfide and ferrous sulfate, though for short-chain derivatives, organic sulfide is the only component at 5.0 wt.%. Ferrous sulfide is the main component of the tribofilms formed by these derivatives at various additive concentrations. But for short-chain derivatives, these tribofilms consist of ferrous sulfide and ferrous disulfide at 5.0 wt.%, and the appearance of disulfide suggests that the interfacial temperature between the upper ball and three lower balls under these conditions is considerably low. The EP films generated by short-chain derivatives are all composed of organic sulfide and ferrous sulfide, while for long-chain derivatives, ferrous sulfide is the main component.

Originality/value

These low-toxic and oil-soluble dimercaptothiadiazole derivatives are effective in improving the tribological characteristic of the biodegradable lithium grease, and these heterocyclic derivatives may be good substitutes for some harmful traditional additives.

Details

Industrial Lubrication and Tribology, vol. 66 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Open Access
Article
Publication date: 3 March 2023

Qiang Zhang, Xiaofeng Li, Yundong Ma and Wenquan Li

In this paper, the C80 special coal gondola car was taken as the subject, and the load test data of the car body at the center plate, side bearing and coupler measured on the…

Abstract

Purpose

In this paper, the C80 special coal gondola car was taken as the subject, and the load test data of the car body at the center plate, side bearing and coupler measured on the dedicated line were broken down to generate the random load component spectrums of the car body under five working conditions, namely expansion, bouncing, rolling, torsion and pitching according to the typical motion attitude of the car body.

Design/methodology/approach

On the basis of processing the measured load data, the random load component spectrums were equivalently converted into sinusoidal load component spectrums for bench test based on the principle of pseudo-damage equivalence of load. Relying on the fatigue and vibration test bench of the whole railway wagon, by taking each sinusoidal load component spectrum as the simulation target, the time waveform replication (TWR) iteration technology was adopted to create the drive signal of each loading actuator required for the fatigue test of car body on the bench, and the drive signal was corrected based on the equivalence principle of measured stress fatigue damage to obtain the fatigue test loads of car body under various typical working conditions.

Findings

The fatigue test results on the test bench were substantially close to the measured test results on the line. According to the results, the relative error between the fatigue damage of the car body on the test bench and the measured damage on the line was within the range of −16.03%–27.14%.

Originality/value

The bench test results basically reproduced the fatigue damage of the key parts of the car body on the line.

Details

Railway Sciences, vol. 2 no. 1
Type: Research Article
ISSN: 2755-0907

Keywords

Article
Publication date: 14 October 2020

Min Zhang, Lin Sun, Fang Qin and G. Alan Wang

In recent years, more and more e-retailers have adopted live streaming services to attract customers. Although the extant literature has mostly examined the motivations for live…

4840

Abstract

Purpose

In recent years, more and more e-retailers have adopted live streaming services to attract customers. Although the extant literature has mostly examined the motivations for live streaming usage, it remains unclear how to enhance customers’ purchase behaviour. Based on the social exchange theory, in the context of live streaming platforms (LSP), this study aims to investigate the impact of information quality and interaction quality on swift guanxi and customers’ purchase intention.

Design/methodology/approach

This study conducted an online survey to conduct two rounds of data collection and analyses the data using SPSS and SmartPLS softwares.

Findings

The results show that information quality (believability, usefulness and vividness) and interaction quality (responsiveness, real-time interaction and empathy) are positively related to swift guanxi, which may influence customers’ online purchase intention on LSP.

Originality/value

Prior service quality studies tend to focus on traditional physical stores and e-commerce websites context. This study offers the description of key dimensions of service quality on emerging LSP context. The study also confirms the importance of swift guanxi in an online marketplace.

Article
Publication date: 7 June 2019

Qian Liu, Zhen Shao, Jian Tang and Weiguo Fan

Drawing upon the theory of planned behavior (TPB) and the self-regulation framework, the purpose of this paper is to investigate whether and how factors for social media…

1537

Abstract

Purpose

Drawing upon the theory of planned behavior (TPB) and the self-regulation framework, the purpose of this paper is to investigate whether and how factors for social media continuance behaviors work differently between social networking sites and microblogging.

Design/methodology/approach

A survey method was used to collect two samples of 557 social networking sites users and 568 microblogging users. The proposed research model was tested with the structural equation modeling technique.

Findings

The empirical results demonstrate that the impacts of influencing factors on users’ continuance behaviors vary by types of social media services. Information sharing has a stronger impact on microblog users’ satisfaction than social network users while social interaction has a stronger impact on satisfaction for social network users than microblog users. In addition, interpersonal influence is more effective in shaping satisfaction for the social network users while media influence is more effective in shaping satisfaction for the microblog users.

Originality/value

This is one of the first studies that integrate TPB with Bagozzi’s self-regulation framework to understand the behavioral model of social networking and microblogging continuance. The findings show that the impacts of attitudinal beliefs regarding information sharing and social interaction on social media users’ satisfaction are different across social networking and microblogging contexts. Moreover, this study also reveals different effects of two specific subjective norms – interpersonal and media influence – on continued use of social networking and microblogging.

Details

Industrial Management & Data Systems, vol. 119 no. 5
Type: Research Article
ISSN: 0263-5577

Keywords

21 – 30 of over 6000