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The research on leaching behaviors of heavy metals in municipal solid waste incineration (MSWI) fly ash is of great significance. Because of the limitations like experimental condition, experiment data volume of heavy metals is difficult to achieve the prediction of requirements. In order to solve the problem of uncertainty and fuzziness caused by small sample, a new method based on fuzzy theory is proposed in this paper. By comparing fitting results from measured data and Visual MINTEQ simulation results, the method in this paper is considered to be more reliable and has a better interpretation for the leaching behaviors of heavy metals. The simulation results show the feasibility and superiority of the proposed method.

In this paper, the mechanical properties and corrosion resistance of CoCr alloy fabricated by selective laser melting (SLM) were studied, and the changes of performance after porcelain sintering process were also analysed. This study is to point out the relationship between the microstructure, mechanical properties and corrosion resistance of CoCr alloys prepared by SLM after porcelain sintering process. In addition, the biosafety of the sintered CoCr alloy was evaluated.

The microscopic feature changes of CoCr alloy samples after porcelain sintering process were observed by DMI 5000 M inverted metallographic microscope and Nova Nano430 FE-SEM. Moreover, phase identification and determination were conducted by X-ray diffraction (XRD) using Smartlab X-ray diffractometer. The Vickers microhardness was measured on the HVS-30 microhardness tester, and tensile tests were carried out on a CM3505 electronic universal testing machine. The corrosion resistance was tested by a classical three-point electrode system electrochemical method, then the ion precipitation was measured by using an atomic absorption spectrometer of Z2000 7JQ8024.

The XRD results indicate that the transition of γ phase (FCC) to e phase (HCP) occurs during the porcelain sintering processing of CoCr alloy. Moreover, the Vickers microhardness of the upper surface and the side surface of the CoCr alloy sample was improved by more than 36%. In addition, the ultimate strength of CoCr alloy via porcelain sintering treatment was increase to 1,395.3 ± 53.0 MPa compared to 1,282.7 ± 10.1 MPa of unprocessed CoCr alloy. However, the corrosion resistance of CoCr alloy samples decreases after porcelain sintering process.

There are few studies on the relationship of microstructure, mechanical properties and corrosion resistance of CoCr alloys prepared by SLM after porcelain sintering process. In this study, the microstructure, mechanical properties and corrosion resistance of CoCr alloy after porcelain sintering process were studied, and the biosafety of the alloy was evaluated. The research found that it is feasible to apply CoCr alloy fabricated by SLM to dental medicine after porcelain sintering process.

This study aims to focus on the optimized design and mechanical properties of gradient triply periodic minimal surface cellular structures manufactured by selective laser melting.

Uniform and gradient IWP and primitive cellular structures have been designed by the optimized function in MATLAB, and selective laser melting technology was applied to manufacture these cellular structures. Finite element analysis was applied to optimize the pinch-off problem, and compressive tests were carried out for the evaluation of mechanical properties of gradient cellular structures.

Finite element analysis shows that the elastic modulus of IWP increased as design parameter b increased, and then decreased when parameter b is higher than 5.5. The highest elastic modulus of primitive increased by 89.2% when parameter b is 6. The compressive behavior of gradient IWP and primitive shows a layer-by-layer way, and elastic modulus and first maximum compressive strength of gradient primitive are higher than that of gradient IWP. The effective energy absorption of gradient cellular structures increased as the average porosity decreased, and the effective energy absorption of gradient primitive is about twice than that of gradient IWP.

This paper presents an optimized design method for the pinch-off problem of gradient triply periodic minimal surface cellular structures.

Although the impacts of trust on information disclosure have been well recognized, the trust building mechanisms in social media are still underexplored. To fill this gap, the purpose of this paper is to explore two trust building mechanisms, namely, institution-based and transference-based trust building and identify how these two mechanisms vary across gender.

An online survey was conducted to collect data. The partial least squares method was used to examine the relationships among regulatory effectiveness, three trusting perceptions and disclosure intention. A cross-group path coefficient comparison method was used to test gender differences.

The results suggest that regulatory effectiveness affects competence- and character-based trust and these impacts are stronger for males than for females. Both competence- and character-based trust influence general trust in members while their impacts vary. Competence-based trust is more important for males while character-based trust is more important for females.

This study contributes to social media literature by identifying the two trust building mechanisms with special attention to the role of regulatory effectiveness and trust transfer. Further, this study also sheds light on how these two mechanisms vary across gender.

This study aims to focus on the heat treatment influence on the corrosion resistance, adhesion of Streptococcus mutans and mechanical properties of CoCrMo alloys manufactured by the selective laser melting (SLM).

CoCrMo alloys were manufactured using the Dimetal-100 machine. X-ray diffraction (XRD), metallographic analysis, scanning electron microscopy (SEM), electrochemical corrosion, Vickers microhardness and tensile tests were used to characterize SLM-produced CoCrMo alloys and compare them with the ones manufactured by casting and with the ASTM F75 standard.

The electrochemical results showed that SLM900 samples had the best corrosion resistance in artificial saliva. The adhesion results showed least propagation and overall quantity of Streptococcus mutans on the SLM900 sample. The microhardness, tensile and yield strength of As-SLM, SLM900 and SLM1200D samples were measured according to the ASTM F75 standard. The elongation of SLM900 was less than 8 per cent, which does not meet the standard specifications. Analysis of the fracture morphology showed that the fracture mechanisms of As-SLM and SLM1200D belong to the quasi-cleavage fracture type, and the mechanical fracture mechanism of SLM900 can be characterized as brittle fracture.

This paper presents the adhesion properties of Streptococcus mutans on the surface of CoCrMo alloys manufactured by SLM and proposes how to regulate the effect of the heat treatment on the corrosion resistance and mechanical properties of CoCrMo alloys manufactured by SLM.

Prior studies fail to reach a consensus on the effects of extrinsic motivation (EM) on knowledge contribution in virtual communities. To fill this research gap, this research proposes two mechanisms of EM – direct effect versus indirect effect via intrinsic motivation (IM) – and introduces prosocial motivation (PSM) as the moderator to define the valence of these two mechanisms.

This research adopts structural equation modeling to validate hypotheses based on 448 responses from XiaoMi online community users.

The results of the moderated mediation analysis show that the direct effect, indirect effect via IM and total effect of EM on knowledge contribution are contingent on the level of PSM. Specifically, as the level of PSM increases, the direct, indirect and total effects of EM on knowledge contribution and the effects of EM on IM change from positive to insignificant and then to negative. Although IM constantly plays an important role across levels of PSM, its effect is stronger when the degree of PSM is high.

This paper advances knowledge of an integrated framework of EM by simultaneously describing its direct and indirect effects, describing its positive and negative effects and untangling the boundary conditions under which each effect of EM applies.

Brand crises are widespread in the marketplace and how consumers perceive and respond to such crises is crucial for brand survival. This paper aims to elucidate the critical role of brand age in shaping consumers’ negative responses to competence-related versus ethics-related crises, with a particular focus on the Eastern cultural context. In addition, the roles of information diagnosticity and culture are investigated.

In a series of four studies conducted across China and the USA, the authors use a rigorous between-subject experimental design to delve into the dynamics of how the interplay between brand age and brand crisis impacts consumers’ negative responses, specifically negative word-of-mouth and boycott tendency, toward brands perceived as guilty.

Results show that brand age helps mitigate the negative responses of consumers in competence-related crises, yet exacerbates such reactions in ethics-related crises. In addition, information diagnosticity mediates the interactive effect of brand crisis and brand age on consumers’ negative responses. However, the results of the cross-cultural comparison study suggest that brand age exaggerates consumers’ negative responses to ethics-related brand crises only in Eastern cultures, but not in the Western contexts.

The research reveals the dual-edged impact of brand age during crises, enriches the literature that draws on information diagnosticity within the hierarchical restrictive schema theory. It also clarifies the boundary mechanisms related to cultural differences.

The findings of this research provide meaningful implications for brand managers by communicating the oldness of a brand may serve to buffer negative consumer responses to competence-related crises but can exacerbate the consequences of ethics-related crises.

This research offers a novel perspective on the nuanced influence of brand age on consumers’ adverse reactions to brand crises. It clarifies why emphasizing the oldness of brands in Eastern-culture markets is effective in mitigating competence-related crises but often counterproductive for ethics-related crises.

The purpose of this paper is to establish an integrated framework of the antecedents of enforcement after contract violations in construction projects and to examine whether contract provisions (control and coordination provisions) and trust (goodwill and competence trust) affect enforcement mechanisms (contractual enforcement and relational enforcement).

A survey method was employed to test the hypotheses. The authors collected data from the Chinese construction industry, and general contractor respondents were asked to answer a questionnaire about a contract violation by one of their subcontractors.

Control provisions and competence trust are positively related to contractual enforcement, but goodwill trust is negatively related to contractual enforcement. Relational enforcement is influenced by goodwill trust and competence trust.

This study treats contract violations as a given variable, and it focuses on contract violations by subcontractors. The cross-sectional design makes it difficult to confirm the causality of the relationships.

Overly strict contractual enforcement can generate disputes and a vicious cycle of retaliation, and overly severe relational enforcement can damage a potentially profitable long-term relationship. In construction projects, the violating party will benefit from this study to avoid excessively contractual enforcement and relational enforcement, thus developing a more collaborative atmosphere on the current project and even establishing a solid long-term relationship.

This study extends the project management literature by investigating the antecedents of enforcement after contract violations, an area not yet fully researched.

The purpose of this study is focused on the mechanical properties of multi-materials porous structures manufactured by selective laser melting (SLM).

The Diamond structure was designed by the triply periodic minimal surface function in MATLAB, and multi-materials porous structures were manufactured by SLM. Compression tests were applied to analyze the anisotropy of mechanical properties of multi-materials porous structures.

Compression results show that the multi-materials porous structure has a strong anisotropy behavior. When the compression force direction is parallel to the material arrangement, multi-materials porous structure was compressed in a layer-by-layer way, which is the traditional deformation of the gradient structure. However, when the compression force direction is perpendicular to the material arrangement, the compression curves show a near-periodic saw-tooth waveform characteristic, and this kind of structure was compressed consistently. It is demonstrated that the combination with high strength brittle material and low strength plastic material improves compression mode, and plastic material plays a role in buffering fracture.

This research provides a new method for the design and manufacturing of multi-materials porous structures and an approach to change the compression behavior of the porous structure.

This study aims to integrate perspectives of transaction costs and capabilities to investigate how the configurational fit between outsourcing strategies, asset specificity of projects and the capabilities of general contractors could achieve high outsourcing performance.

Employing fuzzy-set qualitative comparative analysis, this study analyzes 31 outsourcing cases in construction projects to examine outsourcing performance under different combinations of transaction costs and capabilities.

The findings highlight six different but functionally equivalent configurations to high outsourcing performance, which vary according to attributes of projects and capabilities of contractors. Further, this study develops four context-dependent paths that link outsourcing strategies to high outsourcing performance: leading practitioner, collaborative manager, partnership dependent, and struggler.

How do contractors in construction projects navigate outsourcing practices to high performance? This study provides a configurational perspective to make outsourcing strategy decisions. Based on the firm’s capabilities and project asset specificity, contractors are encouraged to select from six different but functionally equivalent combinations and thereby four outsourcing strategies, namely leading practitioner, collaborative manager, partnership dependent, and struggler, to achieve high outsourcing performance.

This study contributes to the body of knowledge by offering a holistic perspective that integrates production and transaction costs to analyze contractors’ outsourcing strategies, contributing to the integration of the transaction cost perspective and capability perspective.