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The purpose of this paper is to elucidate the influences of the animal fat and fatty acid type on the formation of polycyclic aromatic hydrocarbons (PAHs) and to propose a formation mechanism of PAHs in fat during electric roasting, which is a method of non-direct-contact-flame heating.

The effects of animal fats and model fat on the formation of PAHs were valued on the basis of the ultra high-performance liquid chromatography data. The corresponding products of the FAME pyrolysis were detected by TG-FTIR. The proposal formation mechanism of PAHs was based on the summary of the literature.

Contrary to the International Agency for Research on Cancer, DF had higher risk with 280.53 ng/g of concentration after being roasted than the others animal fats of red meat in terms of PAHs formation. This research also ensured the importance of fat on PAHs formation, the concentration of PAHs in pure fats was higher after being electric roasted than that in meat patties and juice which made from corresponding animal fat. What is more, during pure animal fats and meat products being processed, less PAHs formed in the fat with lower extent of unsaturation and lower content of linolenate. In the same way, methyl linolenate demonstrated the significant increasement to PAHs formation compared to the other fatty acids. And, the number of carbon atom and the extent of unsaturation in fatty acid affects the formation of PAHs during roasting. The detection of alkene and alkane allows to propose a formation mechanism of PAHs during model fat being heated. Further study is required to elucidate the confirm moleculars during the formation of PAHs.

This work studied the effect of the carbon atom number and the unsaturation extent of fats and model fats on the formation of PAHs. This work also assure the important of alkene and alkane on the pyrolysis of model fats. This study also researched the formation and distribution of PAHs in pure fats and meat products after being heated.

Based on definition and characteristic analysis, this paper seeks to propose a formation mechanism of knowledge rigidity, which is constituted by the effects of three precipitating factors: time‐effectiveness of knowledge, reinforcing effectiveness, and sunk cost effect in knowledge selection mechanism.

By presenting knowledge time‐effectiveness model, reinforcing effectiveness model, and knowledge selection mechanism, the paper theoretically analyzes firms' rigid behavior of knowledge application. Theories of increasing returns and sunk cost are introduced to explain the formation process of knowledge rigidity in firms. Two cases are presented to analyze the knowledge rigidity in industrial firms basing on the proposed models and mechanism.

First, the lifecycle of knowledge rigidity is dynamically defined by knowledge time‐effectiveness. Second, the degree of rigidity and firm's dependence on specific knowledge are enhanced by reinforcing effectiveness during the process of application. At the end of the life cycle, the sunk cost mainly hinders a firm's decision making to replace ineffective knowledge.

Quantitative research is needed to further explore the formation mechanism of knowledge rigidity and to present operational approaches for practitioners. The proposed models and mechanism are useful for understanding the knowledge rigidity and analyzing its formation mechanism in firms.

This paper provides theoretical support to realize knowledge rigidity in KM practice. Three indicators were proposed to evaluate the rigidity and action suggestions were given to help control knowledge rigidity in firms.

Causal analysis models and a formation mechanism are proposed to show how knowledge rigidity forms.

Considering the unique characteristics of equity crowdfunding platforms including the removal of stringent structural barriers (e.g. lack of co-location), high visibility and traceability of investor characteristics, large pool of available investors and simplified transaction process, the authors aim to examine how the two most prevalent mechanisms (i.e. homophily and repeated ties) unfold in this context by incorporating the contextual characteristics. The authors theorize an inverted U-shaped relationship between leader-backer similarity and the likelihood of co-investment in a syndicate on equity crowdfunding platforms. In addition, a leader–backer dyad is more likely to form new syndicates if the students have more prior co-investment ties.

The empirical study is based on data from the AngelList syndicate platform and a linear probability model (LPM) with fixed effects is adopted to estimate the syndicate formation.

The authors find that the similarity between a leader and a backer has an inverted U-shaped relationship with the leader and backer's likelihood of co-investment in a syndicate, which is different from the dominant homophily-based tie formation in venture capital (VC) syndicates and other digital platform contexts. Although equity crowdfunding platforms encourage the possibility of exploring new partners, investors are more likely to co-invest with others who have stronger prior ties.

This research theoretically contributes to the scant literature of equity crowdfunding syndicates by contextualizing two most prevalent mechanisms (i.e. homophily and repeated ties) driving tie formation in VC syndicates and digital platforms.

The purpose of this paper is to investigate the film formation mechanism of zirconium-based conversion layer on mild steel. In this way, different approaches were used to show the self-limiting film formation mechanism.

To determine this mechanism, film formation was detected using DC polarization, spectrophotometric technique and surface analysis techniques, including field emission scanning electron microscope (FE-SEM) and atomic force microscopy (AFM).

DC polarization resistance of surface increased with increasing of mild steel immersion time in the conversion coating bath, reaching to a plateau region. On the other hand, zirconium ion concentration decreased during the beginning of the film formation process and continued with a constant concentration, showing the expiry of the process after some minutes.

This paper deals with the film formation mechanism of the zirconium-based conversion layer that includes valuable findings to monitor the process.

Contemporary service and marketing research on value co-creation and value co-destruction assume a one-dimensional view on value, ranging from positive value co-creation, alignment and high value to negative value co-destruction, misalignment and low value. This limitation has recently led researchers to conceptually develop more dynamic spatial-temporal models of how value is formed during the interaction, e.g. in terms of different relationships between practice elements (procedures, understandings and engagements) both within and between actors in “value formation spaces”. However, much of this research awaits validation and is in need of more details. This study aims to address this limitation with the purpose of detailing how and why the mechanisms in such spaces are formed.

Two different and interlinked typologies were analytically derived from previous research and applied on ethnographically-inspired multi-perspective empirical data from a service combining health care and transport service ecosystems, using a combination of interviews, observations and service design methodologies. The design in combination with a practice theory perspective was used to articulate crucial aspects related to understanding the dynamics of value co-formation for elaborative and illustrative purposes.

The study contributes to service theory by conceptualizing as follows: a typology consisting of nine different configurations of practice elements (within and between such elements) and eight possible directions that value formation can take, suggesting a theory that explains value co-creation, value co-destruction and mixed cases.

Although the findings have been developed in a specific empirical context, they articulate a conceptualization applicable to many other service and marketing value co-formation settings.

The typologies are conceptual tools to be used in identifying and measuring the alignment/misalignment of practice elements in complex organizations. The empirical findings uncover service problems faced by disabled customers.

The suggested typologies can guide research and practitioners in understanding and analysing value co-formation mechanisms in complex service settings.

As known, the wire and arc additive manufacture technique can achieve stable process control, which is represented with periodic surface waviness, when using empirical methods or feedback control system. But it is usually a tedious work to further reduce it using trial and error method. The purpose of this paper is to unveil the formation mechanism of surface waviness and develop a method to diminish it.

Two forming mechanisms, wetting and spreading and remelting, are unveiled by cross-section observation. A discriminant is established to differentiate which mechanism is valid to dominate the forming process under the given process parameters.

Finally, a theoretical method is developed to optimize surface waviness, even forming a smooth surface by establishing a matching relation between heat input (line energy) and materials input (the ratio of wire feed speed to travel speed).

Formation mechanisms are revealed by observing cross-section morphology. A discriminant is established to differentiate which mechanism is valid to dominate the forming process under the given process parameters. A mathematical model is developed to optimize surface waviness, even forming a smooth surface through establishing a matching relation between heat input (line energy) and materials input (the ratio of wire feed speed to travel speed).

There have been several reviews of green, ecological and sustainable innovations, but a thorough assessment of green innovation (GI)'s mechanisms in a supply chain setting has not been attempted yet. The purpose of this paper is to review how GI was investigated in supply chains through the lens of a multilevel framework of innovation mechanisms.

The authors provide a comprehensive assessment of prior studies using a systematic literature review approach and content analysis of 136 papers identified from the Web of Science Core Collection database.

Current literature on green innovation supply chains (GISC) has been categorized according to three main causal mechanisms: situational, action-formation and transformational mechanisms. Three different levels of analysis were considered for the three mechanisms: macro, meso and micro. In addition, the authors have also assessed the value creation and appropriation outcomes of GI. The authors identified relevant research gaps in the extant literature and a set of propositions that may guide future research in this area.

This review provides a novel perspective on GISC based on a multilevel theoretical framework of mechanisms.

The causal mechanisms assessment of GISC can be adopted by organizations to convince their SC partners to engage in collaborative and more ambitious initiatives in the field.

The findings of this review could serve as an argument for more encompassing and ambitious GISC initiatives which can be of benefit to society.

A thorough assessment of the interacting mechanisms in GISC has not been attempted before. The authors identify gaps in current literature and provide several propositions for further research avenues based on causal mechanisms framework.

The purpose of the study is to investigate the spatial aspects of underfill flow during the flip-chip encapsulation process, for instance, meniscus evolution and contact line jump (CLJ). Furthermore, a spatial-based void formation mechanism during the underfill flow was formulated.

The meniscus evolution of underfill fluid subtended between the bump array and the CLJ phenomenon were visualized numerically using the micro-mesh unit cell approach. Additionally, the meniscus evolution and CLJ phenomenon were modelled analytically based on the formulation of capillary physics. Meanwhile, the mechanism of void formation was explained numerically and analytically.

Both the proposed analytical and current numerical findings achieved great consensus and were well-validated experimentally. The variation effects of bump pitch on the spatial aspects were analyzed and found that the meniscus arc radius and filling distance increase with the pitch, while the subtended angle of meniscus arc is invariant with the pitch size. For larger pitch, the jump occurs further away from the bump entrance and takes longer time to attain the equilibrium meniscus. This inferred that the concavity of meniscus arc was influenced by the bump pitch. On the voiding mechanism, air void was formed from the air entrapment because of the fluid-bump interaction. Smaller voids tend to merge into a bigger void through necking and, subsequently, propagate along the underfill flow.

The microscopic spatial analysis of underfill flow would explain fundamentally how the bump design will affect the macroscopic filling time. This not only provides alternative visualization tool to analyze flow pattern in the industry but also enables the development of accurate analytical filling time model. Moreover, the void formation mechanism gave substantial insights to understand the root causes of void defects and allow possible solutions to be formulated to tackle this issue. Additionally, the microfluidics sector could also benefit from these spatial analysis insights.

Spatial analysis on underfill flow is scarcely conducted, as the past research studies mainly emphasized on the temporal aspects. Additionally, this work presented a new mechanism on the void formation based on the fluid-bump interaction, in which the formation and propagation of micro-voids were numerically visualized for the first time. The findings from current work provided fundamental information on the flow interaction between underfill fluid and solder bump to the package designers for optimization work and process enhancement.

Although a dominant marketing concept, value co-creation (VCC) is not without controversy. Inspired by value co-destruction (VCD), the purpose of this paper is to review the scattered literature on the uncertainties in collaborative value formation, synthesising contingency factors of value outcomes in VCC.

The paper is based on an examination of 84 peer-reviewed journal articles. Recognising the drawbacks of the macroscopic abstraction in existing the VCC literature, the authors adopt a zooming-in approach to identify distinct patterns of contingency factors in the collaborative value-formation process.

From a macro-social perspective, VCC may connote a sense of exploitation of “consumers” and a need for consumer control of “producers”, impeding harmonious value formation. Zooming into actor-to-actor interactions, the collaborative relationship is found to be a source of uncertainties in value formation, which is further complicated by differences in the knowledge intensities of services. Finally, reviewing the individual consumer reveals a most nuanced picture that demonstrates heterogeneities of consumers’ VCC involvement and complexities in their perceptions and behaviours. Five propositions and a contingency framework are proposed.

Six value formation mechanisms are proposed based on interconnected and multi-level perspectives, providing implications for managers and future researchers.

This paper contributes to rebalancing VCC research by synthesising insights on the potential contingencies, which are relatively under-explored yet vital to keep the controversy alive and relevant, and re-invigorating business processes.

To fabricate high performance parts, this paper aims to systematically study the pores characteristics and their formation mechanisms in selective laser melting (SLM) AlSi10Mg.

Cubes of 10 × 10 × 5 mm were manufactured in different laser power, scan speed and scan space. Optical microscope (OM) and scanning electron microscopes (SEM) were used to observe morphology of pores.

Round or irregular pores were found in SLMed AlSi10Mg parts. All the round pores have smooth inner walls and locate in the melt pool. The formation mechanisms of the round pores are contributed to the evaporation of elements in the melt pool, H₂O, high laser energy input and hollow powder. Irregular pores have rough inner walls. Big scan space, unevenness of the upper surface, large layer thickness, spatter and oxide are the main reasons of generating irregular pores which outside the melt pool. Instability of keyhole leads to the irregular pores locate in the bottom of keyhole mode melt pool.

Relationship between pores and melt pool were studied systematically for the first time. Researches of pores characteristics and their formation mechanisms in SLMed AlSi10Mg would be a valuable reference for researchers to obtain an important insight into and control the defect in SLMed Al alloy.