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1 – 10 of 490Xiaohu Wen, Xiangkang Cao, Xiao-ze Ma, Zefan Zhang and Zehua Dong
The purpose of this paper was to prepare a ternary hierarchical rough particle to accelerate the anti-corrosive design for coastal concrete infrastructures.
Abstract
Purpose
The purpose of this paper was to prepare a ternary hierarchical rough particle to accelerate the anti-corrosive design for coastal concrete infrastructures.
Design/methodology/approach
A kind of micro-nano hydrophobic ternary microparticles was fabricated from SiO2/halloysite nanotubes (HNTs) and recycled concrete powders (RCPs), which was then mixed with sodium silicate and silane to form an inorganic slurry. The slurry was further sprayed on the concrete surface to construct a superhydrophobic coating (SHC). Transmission electron microscopy and energy-dispersive X-ray spectroscopy mappings demonstrate that the nano-sized SiO2 has been grafted on the sub-micron HNTs and then further adhered to the surface of micro-sized RCP, forming a kind of superhydrophobic particles (SiO2/HNTs@RCP) featured of abundant micro-nano hierarchical structures.
Findings
The SHC surface presents excellent superhydrophobicity with the water contact angle >156°. Electrochemical tests indicate that the corrosion rate of mild steel rebar in coated concrete reduces three-order magnitudes relative to the uncoated one in 3.5% NaCl solution. Water uptake and chloride ion (Cl-) diffusion tests show that the SHC exhibits high H2O and Cl- ions barrier properties thanks to the pore-sealing and water-repellence properties of SiO2/HNTs@RCP particles. Furthermore, the SHC possesses considerable mechanical durability and outstanding self-cleaning ability.
Originality/value
SHC inhibits water uptake, Cl- diffusion and rebar corrosion of concrete, which will promote the sustainable application of concrete waste in anti-corrosive concrete projects.
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Shanmugan Subramani and Mutharasu Devarajan
Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested…
Abstract
Purpose
Polymer-based thermal interface materials (TIMs) are having pump out problem and could be resolved for reliable application. Solid-based interface materials have been suggested and reported. The purpose of this paper is suggesting thin film-based TIM to sustain the light-emiting diode (LED) performance and electronic device miniaturization.
Design/methodology/approach
Consequently, ZnO thin film at various thicknesses was prepared by chemical vapour deposition (CVD) method and tested their thermal behaviour using thermal transient analysis as solid TIM for high-power LED.
Findings
Low value in total thermal resistance (Rth-tot) was observed for ZnO thin film boundary condition than bare Al boundary condition. The measured interface (ZnO thin film) resistance {(Rth-bhs) thermal resistance of the interface layer (thin film) placed between metal core printed circuit board (MCPCB) board and Al substrates} was nearly equal to Ag paste boundary condition and showed low values for ZnO film prepared at 30 min process time measured at 700 mA. The TJ value of LED mounted on ZnO thin film (prepared at 30 min.) coated Al substrates was measured to be 74.8°C. High value in junction temperature difference (ΔTJ) of about 4.7°C was noticed with 30 min processed ZnO thin film when compared with Al boundary condition. Low correlated colour temperature and high luminous flux values of tested LED were also observed with ZnO thin film boundary condition (processed at 30 min) compared with both Al substrate and Ag paste boundary condition.
Originality/value
Overall, 30 min CVD processed ZnO thin film would be an alternative for commercial TIM to achieve efficient thermal management. This will increase the life span of the LED as the proposed material decreases the TJ values.
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Vahid Ahmadi, Seyed Mohammad Ali Hosseini, Effat Jamalizadeh and Razie Naghizade
This paper aims to investigate the corrosion resistance of two types of coatings – one is ceria sol coating and the other is ceria sol coating modified by ZnO nanoparticles on…
Abstract
Purpose
This paper aims to investigate the corrosion resistance of two types of coatings – one is ceria sol coating and the other is ceria sol coating modified by ZnO nanoparticles on 7075 aluminum alloy in 3.5% NaCl solution.
Design/methodology/approach
Aluminum alloys were dipped into ceria sol and ceria sol modified by ZnO nanoparticles separately and removed after 10 min from the solutions and dried at 110°C for 30 min and heated at 500 °C for 30 min to form the coatings. The coatings have been characterized by using field emission scanning electron microscopy (FE-SEM), electrochemical impedance spectroscopy (EIS), X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The EIS tests were performed in a corrosive solution of 3.5% NaCl.
Findings
The results showed that the coating of ceria sol modified by ZnO nanoparticles has higher corrosion resistance than the ceria sol coating and the bare sample. Also, the best efficiency is related to aluminum sample immersion after 1 h in NaCl corrosive solution for coating modified by ZnO nanoparticles.
Originality/value
In this research, the modification of ceria sol coating by ZnO nanoparticles had an effect on improving the corrosion behavior of aluminum alloy. It is also understood that modification of coatings is an effective parameter on corrosion resistance.
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Kexin Liu, Shuhan Meng, Yi Zhang, Peng Zhou, Tao Zhang and Fuhui Wang
The purpose of this paper is to investigate the effect of plasma electrolytic oxidation (PEO) coatings and sealed PEO coatings on the corrosion resistance and cytocompatibility of…
Abstract
Purpose
The purpose of this paper is to investigate the effect of plasma electrolytic oxidation (PEO) coatings and sealed PEO coatings on the corrosion resistance and cytocompatibility of a novel Mg-1Zn-0.45Ca alloy in simulated body fluid (SBF).
Design/methodology/approach
The microstructure, corrosion resistance and cytocompatibility of PEO coatings and phosphate conversion-treated PEO coatings were investigated and was compared with the bare Mg alloy.
Findings
The hot-extruded Mg-Zn-Ca alloy exhibit inhomogeneous microstructure and suffered from localized corrosion in the SBF. The PEO coating after phosphate conversion treatment offers enhanced protectiveness to the Mg alloy within an immersion period of up to 60 days, which is significantly improved compared with the performance of the PEO-coated Mg alloy, but the cytocompatibility was slightly decreased.
Originality/value
This work offers new perspective in balancing the protectiveness and cytocompatibility of bio-materials.
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Faris ALshubiri and Mawih Kareem Al Ani
This study aims to analyse the intellectual property rights (INPR), foreign direct investment (FDI) inflows and technological exports of 32 developing and developed countries for…
Abstract
Purpose
This study aims to analyse the intellectual property rights (INPR), foreign direct investment (FDI) inflows and technological exports of 32 developing and developed countries for the period of 2006–2020.
Design/methodology/approach
Diagnostic tests were used to confirm the panel least squares, fixed effect, random effect, feasible general least squares, dynamic ordinary least squares and fully modified ordinary least squares estimator results as well as to increase the robustness.
Findings
According to the findings for the developing countries, trademark, patent and industrial design applications, each had a significant positive long-run effect on FDI inflows. In addition, there was a significant positive long-run relationship between patent applications and medium- and high-technology exports. Meanwhile, trademark and industrial design applications had a significant negative long-term effect on medium- and high-technology exports. In developed countries, patent and industrial design applications each have a significant negative long-term on medium- and high-technology exports. Furthermore, patent and trademark applications each had a significant negative long-run effect on FDI inflows.
Originality/value
This study contributes significantly to the focus that host countries evaluate the technology gaps between domestic and foreign investors at different industry levels to select the best INPR rules and innovation process by increasing international cooperation. Furthermore, the host countries should follow the structure–conduct–performance paradigm based on analysis of the market structure, strategic firms and industrial dynamics systems.
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Xiaoyu Wang, Siti Hajar Abu Bakar Ah and Zaiton Azman
This study aims to assess the social network and perceived social support among community corrections offenders in China and compare the relationship between different…
Abstract
Purpose
This study aims to assess the social network and perceived social support among community corrections offenders in China and compare the relationship between different sub-dimensions of social support and offenders’ social adaptation.
Design/methodology/approach
A descriptive design combined with self-administered questionnaires was used. A total of 54 valid responses were analysed, with participants displaying the following demographic characteristics: male offenders outnumbered female offenders, probationers constituted the highest proportion among all community corrections offenders and educational levels were generally low. Descriptive statistics and correlation analysis were conducted. The Lubben Social Network Scale, Interpersonal Support Evaluation List Scale and Person at Re-education-centre Social Adaptation Scale were used to measure the variables.
Findings
Participants exhibited generally good levels of social support, with moderately extensive social networks and perceived support. All sub-dimensions showed significant positive correlations with social adaptation, with the highest correlation for appraisal support (r = 0.743, p < 0.01), followed by instrumental support (r = 0.714, p < 0.01), emotional support (r = 0.687, p < 0.01), informational support (r = 0.685, P < 0.01) and social networks (r = 0.426, p < 0.01).
Practical implications
This study expands the understanding of community corrections offenders in China by focusing on the underexplored Sichuan Province, using empirical methods for data collection. It addresses a gap in previous research by examining both structural and functional support for offenders rather than focusing solely on one aspect. The study uses two scales, rarely used in Chinese research, to measure structural and functional support, thereby enhancing research on social support for offenders. Practically, it explores the correlation between social support and re-entry, offering valuable insights for improving offenders’ reintegration into society.
Originality/value
These results underscore the critical role of social networks and perceived social support in reintegrating Chinese community corrections offenders. Distinct from prior research, this study used a more comprehensive scale, less commonly used by Chinese scholars, to enable detailed measurement and analysis, highlighting the significance of both structural and functional support in informing practice in related fields.
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We have come to a point where the common way to characterise what is taking place presently, or, better yet, for the past almost two years, is with the term ‘pandemic’. The task…
Abstract
We have come to a point where the common way to characterise what is taking place presently, or, better yet, for the past almost two years, is with the term ‘pandemic’. The task of this chapter is to bring to awareness certain critical reflections with the hope of disturbing the normalised discourse which excepts the authentic meaning of pandemic, a meaning which affects the totality of the human existence. Following the thoughts of Agamben, Baudrillard, and Heidegger, the hypothesis that this chapter is advancing revolves around the idea that the term ‘pandemic’ has been appropriated by biological thinking excepting its authentic meaning, that is, the ultimate reality of the human existence which is death.
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