Search results

This study aims to characterize the mechanical properties of sintered nano-silver under various sintering processes by nano-indentation tests.

Through microstructure observations and characterization, the influences of sintering process on the microstructure evolutions of sintered nano-silver were presented. And, the indentation load, indentation displacement curves of sintered silver under various sintering processes were measured by using nano-indentation test. Based on the nano-indentation test, a reverse analysis of the finite element calculation was used to determine the yielding stress and hardening exponent.

The porosity decreases with the increase of the sintering temperature, while the average particle size of sintered nano-silver increases with the increase of sintering temperature and sintering time. In addition, the porosity reduced from 34.88%, 30.52%, to 25.04% if the ramp rate was decreased from 25°C/min, 15°C/min, to 5°C/min, respectively. The particle size appears more frequently within 1 µm and 2 µm under the lower ramp rate. With reverse analysis, the strain hardening exponent gradually heightened with the increase of temperature, while the yielding stress value decreased significantly with the increase of temperature. When the sintering time increased, the strain hardening exponent increased slightly.

The mechanical properties of sintered nano-silver under different sintering processes are clearly understood.

This paper could provide a novel perspective on understanding the sintering process effects on the mechanical properties of sintered nano-silver.

Online health question-and-answer (Q&A) forums have developed a new business model whereby listeners (peer patients) can pay to read health information derived from consultations between askers (focal patients) and answerers (physicians). However, research exploring the mechanism behind peer patients' purchase decisions and the specific nature of the information driving these decisions has remained limited. This study aims to develop a theoretical model for understanding how peer patients make such decisions based on limited information, i.e. the first question displayed in each focal patient-physician interaction record, considering argument quality (interrogative form and information details) and source credibility (patient experience of focal patients), including the contingent role of urgency.

The model was tested by text mining 1,960 consultation records from a popular Chinese online health Q&A forum on the Yilu App. These records involved interactions between focal patients and physicians and were purchased by 447,718 peer patients seeking health-related information until this research.

Patient experience embedded in focal patients' questions plays a significant role in inducing peer patients to purchase previous consultation records featuring exchanges between focal patients and physicians; in particular, increasingly detailed information is associated with a reduced probability of making a purchase. When focal patients demonstrate a high level of urgency, the effect of information details is weakened, while the interrogative form is strengthened.

The originality of this study lies in its exploration of the monetization mechanism forming the trilateral relationship between askers (focal patients), answerers (physicians) and listeners (peer patients) in the business model “paying to view others' answers” in the online health Q&A forum and the moderating role of urgency in explaining the mechanism of how first questions influence peer patients' purchasing behavior.

This paper aims to explore the adsorption kinetics of syringin from Syringa oblata Lindl. leaves on macroporous resin and develop an efficient, simple and recyclable technology for the separation and purification of syringin.

Static adsorption and desorption properties of six resins were tested to select a suitable resin for the purification of syringin. Langmuir and Freundlich isotherm models were used to estimate the adsorption behavior of syringin on AB-8 resin. Breakthrough point and eluent volume were determined by dynamic adsorption and desorption tests. High-performance liquid chromatography-electrospray ionization-mass spectrometry was applied to identify the syringin in the purified product [syringin product (SP)]. Antioxidant and antibacterial activities of SP in vitro were evaluated by free radical scavenging ability and biofilm formation inhibitory tests.

AB-8 exhibited the most suitable adsorption and desorption capacity. Adsorption isotherm parameters indicated favorable adsorption between AB-8 and syringin. The optimal results were as follows: for adsorption, the sample concentration was 1.85 mg/mL, the sample volume was 3.5 bed volume (BV), the flow rate was 0.5 mL/min; for desorption, the ethanol concentration was 70%, the elution volume was 2.5 BV, the elution velocity was 1.0 mL/min. SP with 80.28% syringin displayed the potent antioxidant activities and inhibitory effects on biofilm formation of Streptococcus suis.

To the best of authors’ knowledge, there are no reports on purifying syringin from Syringa oblata Lindl. leaves using macroporous resins. This paper may also provide a theoretical reference for the purification of other phenylpropanoid glucosides.

In recent years, the updating speed of products has been significantly accelerated, which not only provides diversified styles for consumers to select from but also makes consumers face selection problems sometimes. In addition, a large number of online reviews for products emerge on many e-commerce websites and influence consumers’ purchasing decisions. The purpose of this study is to propose a method for product selection considering consumer’s expectations and online reviews to support consumers’ purchasing decisions.

The product attributes are divided into two categories, i.e. demand attributes and word-of-mouth (WOM) attributes. For the demand attributes, for which the consumers can give specific quantified expectations, the value function of prospect theory is used to determine the consumer’s perceived values to the alternative products according to consumers’ expectations for these attributes and products’ specifications. For the WOM attributes, for which the consumers cannot give specific quantified expectations, the sentiment analysis method is used to identify the sentiment strengths for these attributes in the online reviews, and then the consumer’s perceived values to the alternative products are determined. On this basis, the product selection methods for single consumers and group consumers are given respectively.

Finally, taking the data of JD.com (https://www.jd.com/) as an example, the practicability and rationality of the method proposed in this paper is validated.

First, a new product selection problem considering consumer’s expectations and online reviews is extracted. Second, the product attributes are considered more comprehensively and are classified into two main categories. Third, the bounded rationality of the consumers in the decision-making process is described more reasonably. Fourth, the sentiment dictionaries for each WOM attribute are constructed and the algorithm step of identifying the sentiment strengths is designed, which can help to identify the sentiment strengths in the online reviews more accurately. Fifth, the situation that a group plans to purchase the same products and the members have inconsistent expectations for the product attributes is considered.

The purpose of this study reported in this paper was to find the correct Mt/M₈ and Dt/a² data lists of Hill Formula. This paper enumerates several kinds of Hill formula data lists presented in different literatures, and the authors hope to draw the correct conclusion.

The eight different forms collected in the research project were compared. The mathematician was asked to give a suggestion from a professional point of view and to arrive at a conclusion.

In all eight cases, the third, the eighth and seventh cases are consistent and are considered reasonable and correct.

First-hand information was not used because of unavailability of the earliest published version of the Hill formula.

It is helpful to the correct application of Hill formula and the calculation of diffusion coefficient. It is also valuable to the study of dyeing kinetics.

The research helps to reduce and avoid the confusion in the application of Hill formula in dyeing kinetics research.

Although the importance of network embeddedness attracted much attention in recent years, the interpretations of the underlying mechanism almost focus on the positive effects and neglect the potential negative aspects. This paper aims to use Chinese listed manufacturing enterprises, in the perspective of network embeddedness, to analyze whether resource curse effects exist in strategic networks of enterprises.

This paper examines the resource curse effect that exists in enterprise networks through analysis of enterprise’s total factors productivity compared with those of its industry peers with different degrees of embeddedness. This paper then uses several different methods, such as clustered fixed and random effect model, core and peripheral model, and generalized method of moments estimation in endogenous checks, to detect network curse effects and reveal three potential mechanisms, including overinvestment, extra maintaining cost and innovation extrusion.

This paper finds that excessive network embeddedness hinders continuous improvement of productivity, which is derived from three mechanisms: excessive network embeddedness makes information redundancy among enterprises, and the imitate-follow effect makes excessive investment seriously; enterprises have to encounter more problems and difficulties, such as information coordination and benefit negotiation, to maintain network relationship, which leads to extra cost; enterprises with abundant network resources may tend to more emphasis on marketable operational abilities, resulting in resource decentralization and less investment on innovation, which is finally not beneficial to productivity improvement in the long run.

Compared with previous literatures, this paper not only enriches the understanding of negative mechanisms in enterprise`s network embeddedness, but also unfolds the inconsistency of network embeddedness effects in practice and finds new evidence that the two types of network embeddedness are consistent in certain circumstances.

The purpose of this paper is to explain how individuals form microblogging habits and why they continue to use microblogs from the perspective of direction social networks.

Drawing on the social network theory and the social presence theory, the authors develop a theoretical framework to explain how individuals form microblogging habits and why they continue to use microblogs. To test the proposed model and examine its external validity, the authors collected data from two microblogs: Twitter and Sina Weibo.

Satisfaction and habit have a significant influence on microblogging continuance intention. Whereas, users’ microblogging habits are developed by two key factors – satisfaction and frequency of past behavior – that are further determined by social presence and social network centrality.

Larger sample size with diverse populations is highly recommended for future studies. In addition, exploring the distinct technical functionalities of microblogs when conceptualizing habit formation would be of benefit in future studies.

In this study, it was found that social presence increases both the satisfaction of users and the frequency of past use behavior. Hence, microblog designers should provide users with greater freedom to modify the form and content of their interface, and enable these modifications to be visible in real time to increase the interactivity of microblogs.

In contrast to past studies that have largely neglected the impacts of the directed social network structure, this study aims to focus on microblogging continuance intention from the directed social network perspective. The results from two independent data sets converge on the conclusion that users’ continuance intention to use is affected by both their conscious evaluations (i.e. satisfaction) and unconscious reactions (i.e. habit).

The purpose of this paper is to focus on investigating the impact of crowd participation on degree of project success, which is defined as the total amount of funds a project can obtain after it reaches its initial funding goal threshold.

Drawing on the theory of crowd capital, this study develops six hypotheses about the impact of crowd capability of a fundraiser (i.e. project updates, goal setting, reward levels and social media usage) and crowd participation (i.e. namely, funds pledge and on-site communication) on degree of project success. The hypotheses are tested using data sets of successful projects collected from two popular crowdfunding websites.

This study finds that funds pledge has an inverse U-shaped relationship with degree of project success. Project updates, reward levels and on-site communication positively influence degree of project success, while funding goal negatively affects degree of project success.

This study contributes to prior literature by investigating the degree of project success determinants using the perspectives of both fundraisers and crowds, which provides a more comprehensive understanding of what makes a crowdfunded project a success.

The empirical results of this study provide fundraisers with guidelines about how to access more funds after achieving the initial funding goals.

This work is one of the first to investigate the degree of project success and its determinants from the perspectives of both fundraisers and crowds.

Effectively engaging patients is critical for the sustainable development of online health communities (OHCs). Although physicians’ general knowledge-sharing, which is free to the public, represents essential resources of OHCs that have been shown to promote patient engagement, little is known about whether such knowledge-sharing can backfire when superfluous knowledge-sharing is perceived as overwhelming and anxiety-provoking. Thus, this study aims to gain a comprehensive understanding of the role of general knowledge-sharing in OHCs by exploring the spillover effects of the depth and breadth of general knowledge-sharing on patient engagement.

The research model is established based on a knowledge-based view and the literature on knowledge-sharing in OHCs. Then the authors test the research model and associated hypotheses with objective data from a leading OHC.

Although counterintuitive, the findings revealed an inverted U-shape relationship between general knowledge-sharing (depth and breadth of knowledge-sharing) and patient engagement that is positively associated with physicians’ number of patients. Specifically, the positive effects of depth and breadth of general knowledge-sharing increase and then decrease as the quantity of general knowledge-sharing grows. In addition, physicians’ offline and online professional status negatively moderated these curvilinear relationships.

This study further enriches the literature on knowledge-sharing and the operations of OHCs from a novel perspective while also offering significant specific implications for OHCs practitioners.

The purpose of this study is to prepare a polydopamine (PDA)–palygorskite (Pal) hybrid-reinforced epoxy coating with high adhesion strength on wet concrete surface.

One synthetic step was adopted to prepare novel PDA–Pal hybrid epoxy coating. The process and product were analyzed and confirmed by FIRT, thermogravimetric analysis and scanning electron microscopy. The mass fraction of PDA–Pal hybrid affecting the adhesion strength of epoxy coating was analyzed and confirmed by pull-off test.

PDA–Pal hybrid mass fractions of 0, 1, 3 and 5 were added to the coatings. For a 5 Wt.% PDA–Pal hybrid content, the adhesive strengths on the saturated or underwater concrete surfaces increased to 4.0 and 2.5 MPa, respectively. In addition, the tensile mechanical property of the epoxy coating improved significantly after PDA–Pal addition.

This new epoxy coating hybrid by PDA–Pal could be applied as a concrete protective layer near water or in wet or damp environments.

Introduction of PDA–Pal hybrid to prepare epoxy coating with high adhesion strength on wet concrete surface has not been systematically studied previously.