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Article
Publication date: 14 March 2024

Fangfang Hou, Boying Li, Zhengzhi Guan, Alain Yee Loong Chong and Chee Wei Phang

Despite the burgeoning popularity of virtual gifting in live streaming, research lacks an in-depth understanding of the drivers behind this behavior. Using para-social…

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Abstract

Purpose

Despite the burgeoning popularity of virtual gifting in live streaming, research lacks an in-depth understanding of the drivers behind this behavior. Using para-social relationship (PSR), this study aims to capture viewers’ lively social feelings toward the streamer as the key factor leading to the purchase behavior of virtual gifts. It also aims to establish a theoretical link between PSR and viewers’ holistic experience in live streaming as captured by cognitive absorption and aims to investigates the role of technological features (i.e. viewer–streamer and viewer–viewer interactivity, streamer-level and viewer-level deep profiling and design aesthetics) in shaping viewers’ experience.

Design/methodology/approach

Based on 433 survey responses, this study employs a combination of structural equation modeling and neural networks to offer valuable insights into the relationships between the technological environment, viewer experience and viewer behavior.

Findings

Our results highlight the salience of PSR in promoting the purchase of virtual gifts through cognitive absorption and the importance of the technological environment in eliciting the viewer experience. This study sheds light on the development of PSR in a technological environment and its relationship with cognitive absorption.

Originality/value

By applying PSR to conceptualize viewers’ perceived connection with the streamer, this study extends the research on purchase behavior in the non-shopping context by providing an enlightened understanding of virtual gift purchase behavior in live streaming. Moreover, by theoretically linking PSR with cognitive absorption, virtual gift purchase and technological features of live streaming, it enriches the theory of PSR and bridges the gap between the design practice of supporting the IT infrastructure of live streaming and research.

Details

Internet Research, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1066-2243

Keywords

Article
Publication date: 15 February 2024

Saliq Shamim Shah, Daljeet Singh, Jaswinder Singh Saini and Naveen Garg

This paper aims to study the design and characterization of a 3D printed tetrakaidecahedron cell-based acoustic metamaterial. At present, the mitigation of low-frequency noise…

Abstract

Purpose

This paper aims to study the design and characterization of a 3D printed tetrakaidecahedron cell-based acoustic metamaterial. At present, the mitigation of low-frequency noise involves the utilization of spatially demanding materials for the absorption of sound. These materials lack the ability for targeted frequency control adjustments. Hence, there is a requirement for an approach that can effectively manage low-frequency noise using lightweight and durable materials.

Design/methodology/approach

The CAD model was created in SolidWorks and was manufactured using the Digital Light Processing (DLP) 3D printing technique. Experimental study and numerical simulations examined the metamaterial’s acoustic absorption. An impedance tube with two microphones was used to determine the absorption coefficient of the metamaterial. The simulations were run in a thermoviscous module.

Findings

The testing of acoustic samples highlighted the effects of geometric parameters on acoustic performance. Increment of the strut length by 0.4 mm led to a shift in response to a lower frequency by 500 Hz. Peak absorption rose from 0.461 to 0.690 as the strut diameter was increased from 0.6 to 1.0 mm. Increasing the number of cells from 8 to 20 increased the absorption coefficient and lowered the response frequency.

Originality/value

DLP 3D printing technique was used to successfully manufacture tetrakaidecahedron-based acoustic metamaterial samples. A novel study on the effects of geometric parameters of tetrakaidecahedron cell-based acoustic metamaterial on the acoustic absorption coefficient was conducted, which seemed to be missing in the literature.

Article
Publication date: 21 November 2022

Aissa Boucedra and Madani Bederina

This paper aims to characterize and develop a new ecological lightweight concrete reinforced by addition of palm plant fibers (from vegetal waste) to be used in the thermal and…

Abstract

Purpose

This paper aims to characterize and develop a new ecological lightweight concrete reinforced by addition of palm plant fibers (from vegetal waste) to be used in the thermal and acoustical insulation of local constructions. The date palm plant fibers are characterized by their low sensitivity to chemical reactions, low cost and large availability in local regions. Therefore, the newly obtained lightweight concrete may suggest a great interest, as it seems to be able to achieve good solutions for local construction problems, technically, economically and ecologically.

Design/methodology/approach

The experimental program focused on developing the composition of palm-fiber-reinforced concrete, by studying the effect of the length of the fibers (10, 20, 30 and 40 mm) and their mass percentage (0.5%, 1%, 1.5% and 2%), on the mechanical and acoustical properties of the composite. The main measured parameters were the compressive strength and flexural strength, sound absorption coefficient, noise reduction coefficient (NRC), etc. These tests were also borne out by the measure of density and water absorption, as well as microstructure analyses. To fully appreciate the behavior of the material, visualizations under optical microscope and scanning electron microscope analyses were carried out.

Findings

The addition of plant fibers to concrete made it possible to formulate a new lightweight concrete having interesting properties. The addition of date palm fibers significantly decreased the density of the concrete and consequently reduced its mechanical strength, particularly in compression. Acceptable compressive strength values were possible, according to the fibers content, while better values have been obtained in flexion. On the other hand, good acoustical performances were obtained: a considerable increase in the sound absorption coefficient and the NRC was recorded, according to the content and length of fibers. Even the rheological behavior has been improved with the addition of fibers, but with short fibers only.

Originality/value

Over the recent decades, many studies have attempted to search for more sustainable and environmentally friendly building materials. Therefore, this work aims to study the possibility of using waste from date palm trees as fibers in concrete instead of the conventionally used fibers. Although many researches have already been conducted on the effect of palm plant fibers on the mechanical/physical properties of concrete, no information is available neither on the formulation of this type of concrete nor on its acoustical properties. Indeed, due to the scarcity of raw materials and the excessive consumption of energy, the trend of plant fibers as resources, which are natural and renewable, is very attractive. It is therefore a major recycling project of waste and recovery of local materials.

Details

World Journal of Engineering, vol. 21 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Article
Publication date: 5 May 2022

Dat Van Truong, Song Thanh Quynh Le and Huong Mai Bui

Kapok was well-known for its oleophilic properties, but its mechanical properties and morphology impeded it from forming suitable absorbent materials. This study aims to…

Abstract

Purpose

Kapok was well-known for its oleophilic properties, but its mechanical properties and morphology impeded it from forming suitable absorbent materials. This study aims to demonstrate the process of creating an oil-absorbent web from a blend of treated kapok and polypropylene fibers.

Design/methodology/approach

Kapok fibers were separated from dried fruits, then the wax was removed with an HCl solution at different concentrations. The morphological and structural changes of these fibers were investigated using scanning electron microscopy images. The blending ratios of kapok and polypropylene fibers were 60/40, 70/30 and 80/20, respectively. The fiber blends were fed to a laboratory carding machine to form a web and then consolidated using the heat press technique. The absorption behavior of the formed web was evaluated regarding oil absorption capacity and oil retention capacity according to ASTM 726.

Findings

The results showed that the HCl concentration of 1.0% (wt%) gave the highest wax removal efficiency without damaging the kapok fibers. This study found that oil absorbency is influenced by the fiber blending ratio, web tensile strength and elongation, porosity, oil type and environmental conditions. The oil-absorbency of the web can be re-used for at least 20 cycles.

Research limitations/implications

This study only looked at three types of oils: diesel, kerosene and vegetable oils.

Practical implications

When the problem of oil spills in rivers and seas is growing and causing serious environmental and economic consequences, using physical methods to recover oil spills is the most effective solution.

Originality/value

This research adds to the possibility of using kapok fiber in the form of a web of non-woven fabric for practical purposes.

Details

Research Journal of Textile and Apparel, vol. 28 no. 1
Type: Research Article
ISSN: 1560-6074

Keywords

Article
Publication date: 9 January 2024

Chunfu Wu, Guorui Ye, Yonghong Zhao, Baowen Ye, Tao Wang, Liangmo Wang and Zeming Zhang

Auxetics metamaterials show high performance in their specific characteristics, while the absolute stiffness and strength are much weaker due to substantial porosity. This paper…

Abstract

Purpose

Auxetics metamaterials show high performance in their specific characteristics, while the absolute stiffness and strength are much weaker due to substantial porosity. This paper aims to propose a novel auxetic honeycomb structure manufactured using selective laser melting and study the enhanced mechanical performance when subjected to in-plane compression loading.

Design/methodology/approach

A novel composite structure was designed and fabricated on the basis of an arrowhead auxetic honeycomb and filled with polyurethane foam. The deformation mechanism and mechanical responses of the structure with different structural parameters were investigated experimentally and numerically. With the verified simulation models, the effects of parameters on compression strength and energy absorption characteristics were further discussed through parametric analysis.

Findings

A good agreement was achieved between the experimental and simulation results, showing an evidently enhanced compression strength and energy absorption capacity. The interaction between the auxetic honeycomb and foam reveals to exploit a reinforcement effect on the compression performance. The parametric analysis indicates that the composite with smaller included angel and higher foam density exhibits higher plateau stress and better specific energy absorption, while increasing strut thickness is undesirable for high energy absorption efficiency.

Originality/value

The results of this study served to demonstrate an enhanced mechanical performance for the foam filled auxetic honeycomb, which is expected to be exploited with applications in aerospace, automobile, civil engineering and protective devices. The findings of this study can provide numerical and experimental references for the design of structural parameters.

Details

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

Keywords

Article
Publication date: 4 December 2023

Bahareh Nikmehr, Bidur Kafle and Riyadh Al-Ameri

Concrete, the second most used material in the world, surpassed only by water, relies on a vast amount of cement. The process of cement production emits substantial amounts of…

Abstract

Purpose

Concrete, the second most used material in the world, surpassed only by water, relies on a vast amount of cement. The process of cement production emits substantial amounts of carbon dioxide (CO2). Consequently, it is crucial to search for cement alternatives. Geopolymer concrete (GC) uses industrial by-product material instead of traditional cement, which not only reduces CO2 emissions but also enhances concrete durability. On the other hand, the disposal of concrete waste in the landfills represents a significant environmental challenge, emphasising the urgent need for sustainable solutions. This study aimed to investigate waste concrete's best form and rate as the alternative aggregates in self-compacting and ambient-cured GC to preserve natural resources, reduce construction and demolition waste and decrease pertinent CO2 emissions. The binding material employed in this research encompasses fly ash, slag, micro fly ash and anhydrous sodium metasilicate as an alkali activator. It also introduces the best treatment method to improve the recycled concrete aggregate (RCA) quality.

Design/methodology/approach

A total of25%, 50% and 100% of coarse aggregates are replaced with RCAs to cast self-compacting geopolymer concrete (SCGC) and assess the impact of RCA on the fresh, hardened and water absorption properties of the ambient-cured GC. Geopolymer slurry was used for coating RCAs and the authors examined the effect of one-day and seven-day cured coated RCA. The mechanical properties (compressive strength, splitting tensile strength and modulus of elasticity), rheological properties (slump flow, T500 and J-ring) and total water absorption of RCA-based SCGC were studied. The microstructural and chemical compositions of the concrete mixes were studied by the methods of energy dispersive X-Ray and scanning electron microscopy.

Findings

It is evident from the test observations that 100% replacement of natural aggregate with coated RCA using geopolymer slurry containing fly ash, slag, micro fly ash and anhydrous sodium metasilicate cured for one day before mixing enhances the concrete's quality and complies with the flowability requirements. Assessment is based on the fresh and hardened properties of the SCGC with various RCA contents and coating periods. The fresh properties of the mix with a seven-day curing time for coated RCA did not meet the requirements for self-compacting concrete, while this mix demonstrated better compressive strength (31.61 MPa) and modulus of elasticity (15.39 GPa) compared to 29.36 MPa and 9.8 GPa, respectively, for the mix with one-day cured coated RCA. However, incorporating one-day-cured coated RCA in SCGC demonstrated better splitting tensile strength (2.32 MPa) and water absorption (15.16%).

Research limitations/implications

A potential limitation of this study on SCGC with coated RCAs is the focus on the short-term behaviour of this concrete. This limited time frame may not meet the long-term requirements for ensuring the sustained durability of the structures throughout their service life.

Originality/value

This paper highlights the treatment technique of coating RCA with geopolymer slurry for casting SCGC.

Details

Smart and Sustainable Built Environment, vol. 13 no. 2
Type: Research Article
ISSN: 2046-6099

Keywords

Article
Publication date: 1 March 2023

Yuzhen Zhao, Mingxu Zhao, Huimin Zhang, Xiangrong Zhao, Yang Zhao, Zhun Guo, Jianjing Gao, Cheng Ma and Yongming Zhang

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

Abstract

Purpose

This paper aims to prepare third-order nonlinear optical (NLO) organic materials with large nonlinear optimization value, high damage threshold and ultrafast response time.

Design/methodology/approach

A series of novel symmetric and asymmetric compounds possessing third-order NLO properties were synthesized using 1,3,5-tribromobenzene as the basis. The photophysical and electrochemical properties, as well as the click reactions, were characterized by means of UV–VIS–NIR absorption spectroscopy and cyclic voltammetry.

Findings

The donor–acceptor chromophores were inserted into compound, making the molecule to have a broader absorption in the near-infrared regions and a narrower optical and electrochemical band gap. It also formed an electron-delocalized organic system, which has larger effects on achieving a third-order NLO response. The third-order NLO phenomenon of benzene ring complexes was experimentally studied at 532 nm using Z-scan technology, and some compounds showed the expected NLO properties.

Originality/value

The click products exhibit more NLO phenomena by performing different click combinations to the side groups, opening new perspectives on using the system in a variety of photoelectric applications.

Details

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

Keywords

Article
Publication date: 26 January 2024

Mustafa S. Al-Khazraji

Auxetic sandwich structures are gaining attention because of the negative Poisson’s ratio effect offered by these structures. Re-entrant core was one configuration of the auxetic…

Abstract

Purpose

Auxetic sandwich structures are gaining attention because of the negative Poisson’s ratio effect offered by these structures. Re-entrant core was one configuration of the auxetic structures. There is a growing concern about the design and behavior of re-entrant cores in aerospace, marine and protection applications. Several researchers proposed various designs of re-entrant core sandwiches with various materials. The purpose of this study is to review the most recent advances in re-entrant core sandwich structures. This review serves as a guide for researchers conducting further research in this wide field of study.

Design/methodology/approach

The re-entrant core sandwich structures were reviewed in terms of their design improvements, impact and quasi-static crushing responses. Several design improvements were reviewed including 2D cell, 3D cell, gradient, hierarchical and hybrid configurations. Some common applications of the re-entrant core sandwiches were given at the end of this paper with suggestions for future developments in this field.

Findings

Generally, the re-entrant configuration showed improved energy absorption and impact response among auxetic structures. The main manufacturing method for re-entrant core manufacturing was additive manufacturing. The negative Poisson’s ratio effect of the re-entrant core provided a wide area of research.

Originality/value

Generally, re-entrant cores were mentioned in the review articles as part of other auxetic structures. However, in this review, the focus was solely made on the re-entrant core sandwiches with their mechanics.

Details

Aircraft Engineering and Aerospace Technology, vol. 96 no. 2
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 8 February 2024

Isaac Bawuah

This study investigates the relationship between bank capital and liquidity creation and further examines the effect that institutional quality has on this relationship in…

Abstract

Purpose

This study investigates the relationship between bank capital and liquidity creation and further examines the effect that institutional quality has on this relationship in Sub-Saharan Africa (SSA).

Design/methodology/approach

The data comprise 41 universal banks in nine SSA countries from 2010 to 2022. The study employs the two-step system generalized methods of moments and further uses alternative estimators such as the fixed-effect and two-stage least squares methods.

Findings

The empirical results show that bank capital has a direct positive and significant effect on liquidity creation. In addition, the positive effect of bank capital on liquidity creation is enhanced, particularly in a strong institutional environment. The results imply that nonconstraining capital regulatory policies bolster bank solvency, improve risk-absorption capacity and increase liquidity creation.

Practical implications

This study has several policy implications. First, it provides empirical evidence on the position of banks in SSA on the financial fragility and risk-absorption hypothesis of bank capital and liquidity creation debates. This study shows that the effect of bank capital on liquidity creation in SSA countries is positive and supports the risk-absorption hypothesis. Second, this study highlights that a country's quality institutions can complement bank capital to increase liquidity creation. In addition, this study highlights that nonconstraining capital regulatory policies will bolster bank solvency, improve risk-absorption capacity and increase liquidity creation.

Originality/value

The novelty of this study is that it introduces the country's quality institutional environment into bank capital and liquidity creation links for the first time in SSA.

Details

African Journal of Economic and Management Studies, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-0705

Keywords

Article
Publication date: 8 September 2022

Asieh Yahyazadeh, Enayatollah Moradi Rufchahi, Hessamoddin Yousefi and Seyyedeh Maryam Golzar Poursadeghi

This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and…

Abstract

Purpose

This paper aims to synthesize 6-ethyl-4-hydroxyquinolin-2(1H)-one as a new enol-type coupling component in the preparation of some 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes and evaluate the solvent effects on their absorption in ultraviolet-visible spectra.

Design/methodology/approach

6-Ethyl-4-hydroxyquinolin-2(1H)-one was synthesized by thermal cyclocondensation reaction of N, N′-bis(4-ethylphenyl) malonamide at 130–140°C in polyphosphoric acid. This compound was then applied in the azo-coupling reaction with some aniline-based diazonium salts, so as to prepare seven new mono-heterocyclic azo dyes. The structures of the compounds were confirmed using mass spectroscopic technique. Fourier transform infra red (FT-IR) and 1H proton nuclear magnetic resonance (1H NMR) and carbon-13 nuclear magnetic resonance (13 C NMR) studies on the structure of the azo compounds revealed that they exist as two E- and Z-isomers of hydrazone tautomer both in solid and solution state. The effects of acid and base on the visible absorption spectra of the dyes were also evaluated and discussed.

Findings

Ultra violet-visible UV-vis absorption spectra of the dyes didn’t show significant variation by changing of solvents because of intramolecular H-bonding between proposed hydrazone forms and 2- and 4-keto functions in their structures. The spectra of the dyes were not sensitive to the addition of acid but were very sensitive to base.

Originality/value

The synthesized 3-arylazo-4-hydroxyquinolin-2(1H)-one dyes are new members in the 4-hydroxyquinolin-2(1H)-one azo dyes family, where very few details regarding the synthesis of such dyes are reported before in the literature. They are unique in terms of synthesis and spectral properties.

Details

Pigment & Resin Technology, vol. 53 no. 2
Type: Research Article
ISSN: 0369-9420

Keywords

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