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Strain sensing characteristic of carbon nanotubes has been established in the past at nanoscale. In this study, it is shown that the carbon nanotube film sensors, made up of randomly oriented carbon nanotubes, can be used as strain sensors at macro level. A nearly linear trend between the change in voltage, measured using a movable four point probe, and strains, measured using conventional electrical strain gage, indicates the potential of such carbon nanotube films for measuring flexural strains at macro level. Isotropic strain sensing capability of the carbon nanotube film sensors, due to randomly oriented carbon nanotubes, allows multidirectional and multi‐location measurements.

This study aims to explore how two affective factors (i.e. brand attachment and consumer affinity) influence host country consumers' responses to an international brand alliance (IBA).

A two (brand attachment: high vs low) × two (consumer affinity: high vs low) factorial experiment was conducted with 336 US university students. The partial least squares structural equation modeling (PLS-SEM) method was used to test the conceptual model.

(1) Pre-attachment to the host brand and consumer affinity for the country-of-origin (COO) of the foreign partner brand positively influence attitudes toward the IBA. (2) Attitudes toward the IBA positively influence post-attachment to the host brand, intention to buy the IBA product and willingness to recommend the IBA product. (3) Pre-attachment to the host brand positively influences post-attachment to the host brand.

This study extends the literature on factors influencing attitudes toward IBAs by finding the significant influences of pre-attachment to the host brand and consumer affinity for the COO of the foreign partner brand on host country consumers' responses to IBAs.

Modern construction projects are increasingly complex and rely heavily on multi-discipline collaboration, and this leads to a more and more decentralized project-based structure widely adopted in the construction industry. While job satisfaction (JS) and job performance (JP) have been heavily studied previously, few considered the impact of organizational structure and none investigated the relationship between the organizational decentralization degree with JS and JP. This research aims to fill this research gap and investigate the impacts of organizational decentralization degree on JS and JP and facilitate a better project management practice for large-scale construction projects.

This research firstly establishes four hypotheses based on the literature review on general project-based organizations, then the hypotheses are tested by a survey covering 25 large complex construction projects in China. A hierarchical linear model analysis was carried out to analyze the survey data and to study the relationships between organizational decentralization degree, job satisfaction and job performance.

Analysis results show that projects' employees' JS and JP are positively correlated with the construction project organizations' decentralization degree, respectively. The decentralization degree has a higher impact on JS than on JP. Employees' JP is positively correlated with their JS, and a higher decentralization degree leads to a more significant positive impact that JS puts on JP.

The findings are new evidence of how construction organization structure and its decentralization degree can affect project employees' JS and JP. This research provides valuable guidance for the industry's management practice and is particularly important for large, complex and highly decentralized construction projects.

This paper aims to evaluate the effect of precursors on the anticorrosion property of silica encapsulated waterborne aluminium pigments (WBAPs).

The silica encapsulated WBAPs were prepared using different siloxanes as precursors. The anchorage and compactness of silica films on aluminium flakes were characterized by optical microscopy, scanning electron microscopy and N2 adsorption-desorption. The anticorrosion property and glossiness of WBAPs were evaluated.

The effect of precursors on anticorrosion property of silica encapsulated WBAPs is reflected from the anchorage and the compactness of silica on aluminium flakes surface. Furthermore, the structure of γ-aminopropyl triethoxysilane benefits the anchorage and the compatibility between pigment and acrylic resin. Neither high nor low ratio of tetraethoxysilane/γ-aminopropyl triethoxysilane is favourable to the anchorage and formation of dense silica film on the aluminium flakes surface. To obtain perfect WBAP, the precursors of silica must be carefully selected.

Only four kinds of precursors were used in this work; other precursors could also be studied.

The investigation results provide theoretical basis to obtain excellent WBAPs.

The method to investigate anticorrosion property of WBAPs that is based on the effect of precursors on the performance of silica was novel.

This paper aims to investigate the relationship linking hard technology innovation with the high-quality development (HDP) of SRDI firms. SRDI firms are typically classified as medium-sized to moderately scaled businesses renowned for their specialized, refinement, differentiation and innovation (SRDI), with a focus on providing exceptional products or services to gain a competitive advantage in specific market segments. These firms are dedicated to expanding market share and enhancing innovation capacities both locally and globally. The research also aims to scrutinize the contextual effects of digital transformation within this framework.

Hard technology innovation consists of three essential components: innovative characteristics, newly developed technology-based intellectual property rights and the volume of R&D initiatives. The evaluation of HDP was performed utilizing the entropy method, with a specific emphasis on assessing value creation and value management capabilities. Subsequently, this study explores the impact of technological innovation on the HDP of firms using a dual-dimension fixed effects model.

Every aspect of hard technology innovation is essential for promoting the HDP of businesses. The digital transformation of businesses exerts a heterogeneous moderating influence in this process. This is evident in the constructive impact on the connection between innovation attributes and the volume of fruitful R&D initiatives, as well as the HDP of firms. Conversely, the moderating effect is deemed insignificant in the association between new technology-based intellectual property and HDP.

This research delves deeper into the underlying mechanisms that underlie the promotion of HDP through hard technology innovation, thereby expanding the scope of our exploration on the HDP of SRDI firms. It establishes a theoretical framework and practical directives for achieving enhanced development quality amidst the evolving landscape of digital transformation within firms.

The purpose of this paper is to evaluate the role of encapsulation temperature on the preparation of silica-encapsulated waterborne aluminium pigments.

The waterborne aluminium pigments were prepared with H₂O₂ as anchoring agent and siloxane used as precursors in pH = 9.0 medium at different temperatures. The anchorage and compactness of silicon which on aluminium surface were characterized by optical microscopy, scanning electron microscopy and N₂ adsorption-desorption. The anticorrosion property was characterized by the volume of produced hydrogen as a function of time.

The effect of encapsulation temperature on anticorrosion property of aluminium pigments is reflected from the anchorage and the compactness of silica on aluminium surface. Furthermore, when encapsulation temperature is 45-50°C, the silica platelets uniformly anchored on the aluminium surface as a dense film, which show the best anticorrosion property. Lower and higher encapsulation temperatures cause the silica platelets to agglomerate rather than anchor on the aluminium surface, which is unfavourable for the anchorage and the formation of compact silica film. The use of product in waterborne coatings gives a higher glossiness than that of raw material.

Only pH = 9.0 medium was explored, and the other pH medium could result in different optimum temperatures.

The investigation results provide theoretical basis for obtaining excellent waterborne aluminium pigments.

The method of investigating corrosion resistance mechanism of aluminium pigments based on anchorage and compactness is novel.

This paper aims to provide a review on the process of additive manufacturing of ceramic materials, focusing on partial and full melting of ceramic powder by a high-energy laser beam without the use of binders.

Selective laser sintering or melting (SLS/SLM) techniques are first introduced, followed by analysis of results from silica (SiO₂), zirconia (ZrO₂) and ceramic-reinforced metal matrix composites processed by direct laser sintering and melting.

At the current state of technology, it is still a challenge to fabricate dense ceramic components directly using SLS/SLM. Critical challenges encountered during direct laser melting of ceramic will be discussed, including deposition of ceramic powder layer, interaction between laser and powder particles, dynamic melting and consolidation mechanism of the process and the presence of residual stresses in ceramics processed via SLS/SLM.

Despite the challenges, SLS/SLM still has the potential in fabrication of ceramics. Additional research is needed to understand and establish the optimal interaction between the laser beam and ceramic powder bed for full density part fabrication. Looking into the future, other melting-based techniques for ceramic and composites are presented, along with their potential applications.

An engine component made from 1Cr18Ni9Ti alloy to be used underwater was the subject of the present research investigation.

A stereomicroscope, a metallurgical microscope, a microhardness tester and an electron energy dispersion spectroscope were used to observe cross-sections of the alloy’s microstructure at different locations, as well as its overall corrosion behavior.

The corrosion of the 1Cr18Ni9Ti alloy, attributed to welding, cold processing and plastic deformation processes, was investigated together with an analysis of the chemical composition of the corrosion products and microsclerometry of the cross-sections. It was revealed that defects such as shrinkage cavities and porosity, often were observed to occur in the welding fusion zone. During cold processing treatments, work hardening was induced in the surface layer. Corrosion products consisted of oxides, chlorides and sulfides, with oxides as the dominant component. The high chromium content of d-ferrite had resulted in chromium depletion in nearby phase boundaries, which had led to oxidation and corrosion at these boundaries. As the electrode potential of d-ferrite is different to that of austenite, it is possible for a galvanic couple to develop between the two phases, leading to differential rates of corrosion attack.

Methods are proposed to improve corrosion resistance by improving the quality of the surface overlaying processes and by adopting special surface treatment techniques.

The purpose of this study is to evaluate the role of encapsulation pH and iron source on the anchorage mode and performance of iron oxide-encapsulated aluminium pigments.

The coloured waterborne aluminium pigments were prepared at pH 5-7.5 by using FeSO₄ and FeCl₃ as iron source. The anchorage mode of iron oxides on aluminium was characterized using optical microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction. Furthermore, the pigmentary performance was characterized through anticorrosion test and multi-angle spectroscopy.

Diaspore and boehmite could form from H₂O₂ oxidizing aluminium. Both low pH and FeSO₄ systems are beneficial for diaspore, inducing green rust anchor on the aluminium to form goethite. Either in FeSO₄ or FeCl₃ system, slightly high pH is beneficial for the formation of boehmite, which occurred together with ferrihydrite to form denser coating with yellowness and excellent anticorrosion property. At pH above 7, the formation of dendritic iron oxide is detrimental to the anticorrosion property and the glossiness.

Only FeSO₄·7H₂O and FeCl₃·6H₂O as iron sources were explored.

The investigation results provide theoretical basis to obtain excellent chromatic waterborne aluminium pigments.

The method for investigation of encapsulation mechanism by surveying the structure of iron oxides on aluminium, which varies with the pH of the system and iron sources, is novel.

This paper aims to report a stretchable piezoresistive strain sensor array that can detect various static and dynamic stimuli, including bending, normal force, shear stress and certain range of temperature variation, through sandwiching an array of conductive blocks, made of multiwalled carbon nanotubes (MWCNTs) and polydimethylsiloxane (PDMS) composite. The strain sensor array induces localized resistance changes at different external mechanical forces, which can be potentially implemented as electronic skin.

The working principle is the piezoresistivity of the strain sensor array is based on the tunnelling resistance connection between the fillers and reformation of the percolating path when the PDMS and MWCNT composite deforms. When an external compression stimulus is exerted, the MWCNT inter-filler distance at the conductive block array reduces, resulting in the reduction of the resistance. The resistance between the conductive blocks in the array, on the other hand, increases when the strain sensor is exposed to an external stretching force. The methodology was as follows: Numerical simulation has been performed to study the pressure distribution across the sensor. This method applies two thin layers of conductive elastomer composite across a 2 × 3 conductive block array, where the former is to detect the stretchable force, whereas the latter is to detect the compression force. The fabrication of the strain sensor consists of two main stages: fabricating the conducting block array (detect compression force) and depositing two thin conductive layers (detect stretchable force).

Characterizations have been performed at the sensor pressure response: static and dynamic configuration, strain sensing and temperature sensing. Both pressure and strain sensing are studied in terms of the temporal response. The temporal response shows rapid resistance changes and returns to its original value after the external load is removed. The electrical conductivity of the prototype correlates to the temperature by showing negative temperature coefficient material behaviour with the sensitivity of −0.105 MΩ/°C.

The conductive sensor array can potentially be implemented as electronic skin due to its reaction with mechanical stimuli: compression and stretchable pressure force, strain sensing and temperature sensing.

This prototype enables various static and dynamic stimulus detections, including bending, normal force, shear stress and certain range of temperature variation, through sandwiching an array of conductive blocks, made of MWCNT and PDMS composite. Conventional design might need to integrate different microfeatures to perform the similar task, especially for dynamic force sensing.