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The purpose of this paper is to study the load capacity of nanoparticles-laden gas film (NLGF) in thrust bearing.

SiO₂ nanoparticles were added into gas to form an NLGF. The nanoparticles volume fraction in the film was controlled by a vibrator. The film thickness and the film pressure were measured by a micro cantilever displacement sensor and a membrane pressure sensor, respectively. The total load that makes the film thickness keeping constant was quantified, and then, the film load capacity was obtained.

The investigation shows that nanoparticles can enlarge the film load capacity remarkably; even a little amount of nanoparticles (0.01 per cent) could lead to a sharp rise. With the increase of nanoparticles volume fraction, load capacity increases. However, the increment of load capacity decreases gradually. In addition, the film pressure variation proves the enhancement effect of nanoparticles on the film load capacity.

The paper is restricted to the findings based on NLGF, which is formed by dispersing SiO₂ nanoparticles in gas film as an additive. The experimental results are applicable within the range of nanoparticles volume fraction of 0.01-0.33 per cent.

The fact that nanoparticles could enlarge the gas film load capacity is verified by experiment for the first time. This study reveals the corresponding relation between nanoparticles volume fraction and the film load capacity.

This paper aims to study the impact of the interaction effects between live-streaming marketing and clothing type on consumers' intention to purchase clothing, and the mediating effect of internalization and identification on the relationship between them.

This paper conducts a scenario experiment to 486 consumers who had experience in purchasing clothing on the live-streaming platform and employs the analysis of variance, structural equation model and multivariate regression model.

Our findings reveal that professional live-streaming marketing (PLSM) can better stimulate consumers' intention to purchase formal clothing than entertainment live-streaming marketing (ELSM) does. Compared with PLSM, ELSM can better stimulate consumers' intention to purchase casual clothing. When PLSM promotes formal clothing, it triggers the internalization mechanism of consumers, so as to improve their purchase intention. When ELSM promotes casual clothing, it triggers consumers' identification mechanism, so as to improve their purchase intention.

This paper helps to identify the differences in the impact of different types of live-streaming marketing on consumers' intention to purchase different types of clothing, as well as the mediating role of internalization and identification mechanisms. This paper provides a theoretical reference for clothing firms to strategically select the appropriate type of live-streaming marketing.

This paper aims to successfully synthesize three-dimensional spindle-like Au functionalized Co₃O₄-ZnO nanocomposites; characterize the structure, morphology and surface chemical properties of the products; study the effect of Au NPs doping concentration, operating temperature different gas to, sensing properties; and introduce an attractive gas sensor for acetone detection.

Au NPs functionalized Co₃O₄-ZnO nanocomposite was prepared by coprecipitation and impregnation methods; the structure and surface chemical property of the products were characterized by XRD, SEM, TEM, UV-Vis, BET and XPS. The sensing ability of Au@Co₃O₄-ZnO for acetone and mechanism was analyzed systematically.

The results of gas sensing tests show that the unique component structure, Schottky junction and catalytic effect of Au functionalization make it have low operating temperature, excellent selectivity, high response (10 ppm, 56) and rapid response recovery time.

All the characterization and test data of the prepared materials are provided in this paper and reveals the gas sensing mechanism of the gas sensor.

The detection limit is 2.92–100 ppb acetone. It is promising to be applied in low-power, micro detection and miniature acetone gas sensors.

The gas sensor prepared has a lower working temperature and low detection limit, so it has promising application prospects in low-concentration acetone detection and early warning.

The unique component structure, Schottky junction and catalytic effect of Au functionalization Co₃O₄-ZnO make it have low operating temperature, excellent selectivity and rapid response recovery time.

Improvement and optimization design of a two-stage vibration isolation system proposed in this paper are conducted to ensure the device of electronic work effective.

The proposed two-stage vibration isolation system of airborne equipment is optimized and parameterized based on multi-objective genetic algorithm.

The results show that compared with initial two-stage vibration isolation system, the angular vibration of the two-stage vibration isolation system becomes 3.55 × 10^-4 rad, which decreases by 89%. The linear isolation effect is improved by at least 67.7%.

The optimized two-stage vibration isolation system effectively improves the vibration reduction effect, the resonance peak is obviously improved and the reliability of the mounting bracket and the shock absorber is highly improved, which provides an analysis method for two-stage airborne equipment isolation design under complex dynamic environment.

As a kind of NP-hard combinatorial optimization problem, pipe routing design (PRD) is applied widely in modern industries. In the offshore oil and gas industry, a semi-submersible production platform is an important equipment for oil exploitation and production. PRD is one of the most key parts of the design of semi-submersible platform. This study aims to present an improved ant colony algorithm (IACO) to address PRD for the oil and gas treatment system when designing a semi-submersible production platform.

First, to simplify PRD problem, a novel mathematical model is built according to real constraints and rules. Then, IACO, which combines modified heuristic function, mutation mechanism and dynamical parameter mechanism, is introduced.

Based on a set of specific instances, experiments are carried out, and the experimental results show that the performance of IACO is better than that of two variants of ACO, especially in terms of the convergence speed and swarm diversity. Finally, IACO is used to solve PRD for the oil and gas treatment system of semi-submersible production platform. The simulation results, which include nine pipe paths, demonstrate the practicality and high-efficiency of IACO.

The main contribution of this study is the development of method for solving PRD of a semi-submersible production platform based on the novel mathematical model and the proposed IACO.

Based on the online brand community, this study focuses on how online brand community experience affects customer voice and discusses the relationship between community engagement and community commitment. Specifically, we examine the mediation effect of community engagement between community experience and customer voice and also the moderation role of community commitment.

The survey data is collected through the online survey of people who participate in the online mobile phone brand community. In total, 369 members of online community users (Huawei and Apple communities) were collected as the research samples. Then the structural equation model analysis was tested through the SPSS 25 and Mplus 7 in a two-stage analysis program.

The results show that (1) customer online brand community experience has a positive impact on customer voice; (2) community engagement mediates the positive relationship between online brand community experience and customer voice; and (3) community commitment plays a moderating role between customer experience and customer voice. Compared with low level customer's community commitment, when customer's community commitment is high, the level of community engagement has a greater mediation effect on the positive relationship between community experience and customer voice.

On the one hand, the model of customer community experience to customer voice built in this paper has not been fully validated. Whether the model can get more robust results needs to be extended to more different community scenarios. On the other hand, this paper is actually cross-sectional data, which cannot strictly reveal the causal relationship. The authors recommend that future research may use other research methods to further reveal its internal mechanism.

This paper shows that customer's community experience has an important impact on customer voice behavior. Among them, information experience and sociability remain as the important factor affecting customer voice behavior, which is quiet important for maintaining brand community and product or service improvement. Brand community managers need to consistently create multiple forms of information presentation and interaction channels to enhance the information and social experience of community members.

First, this paper puts forward a new perspective on customer comments or feedback-customer voice, which provides a solid foundation and reference value for future scholars to explore such important phenomena. Second, the relationship between community experience and customer voice behavior was examined, which enriched the research on community experience and also discovered another positive significance of community experience in community construction. Finally, the authors examine the mediation effect of community engagement on customer voice behavior. Community engagement is one of the important indicators that reflexing community performance, which is of great significance to the brand community.

The purpose of this study is to explore the interfacial adhesion between superhydrophobic coatings FC-X (X = 1%, 2%, 3%, 4% and 5%) and the concrete substrate, along with the impact of FC-X on the water repellency characteristics of the concrete substrate.

One synthetic step was adopted to prepare novel F-SiO₂ NP hybrid fluororesin coating. The impact of varying mass fractions of F-SiO₂ NPs on the superhydrophobicity of FC-X was analyzed and subsequently confirmed through water contact angle (WCA) measurements. Superhydrophobic coatings were simply applied to the concrete substrate using a one-step spraying method. The interfacial adhesion between FC-X and the concrete substrate was analyzed using tape pasting tests and abrasion resistance measurements. The influence of FC-X on the water repellency of the concrete substrate was investigated through measurements of water absorption, impermeability and electric flux.

FC-4% exhibits excellent superhydrophobicity, with a WCA of 157.5° and a sliding angle of 2.3°. Compared to control sample, FC-X exhibits better properties, including chemical durability, wear resistance, adhesion strength, abrasion resistance, water resistance and impermeability.

This study offers a thorough investigation into the practical implications of enhancing the durability and water repellency of concrete substrates by using superhydrophobic coatings, particularly FC-4%, which demonstrates exceptional superhydrophobicity alongside remarkable chemical durability, wear resistance, adhesion strength, abrasion resistance, water resistance and impermeability.

Through the examination of the interfacial adhesion between FC-X and the concrete substrate, along with an assessment of FC-X’s impact on the water repellency of the concrete, this paper provides valuable insights into the practical application of superhydrophobic coatings in enhancing the durability and performance of concrete materials.

Manufacturers increasingly resort to digital transformation to shape their competitiveness in the digital economy era, while supply chain (SC) collaborative innovation helps them cope with market uncertainties. However, whether and how digital transformation can facilitate SC collaborative innovation remain unclear. To address this gap, we aims to investigate the effects of digital transformation (strategy and capability) on SC collaborative (process and product) innovation and market performance.

We use partial least squares-structural equation modelling (PLS-SEM) with a sample of 210 Chinese manufacturers to investigate the effects of digital transformation (strategy and capability) on SC collaborative (process and product) innovation and market performance.

The results show that digital strategy and capability positively impact SC collaborative process and product innovation, which enhances market performance. In addition, SC collaborative innovation mediates the relationship between digital transformation and market performance.

This study contributes to the literature by identifying how digital transformation drives SC collaborative innovation towards improving market performance and providing practical guidance for enterprises in promoting digital transformation and SC collaborative innovation.

The purpose of this paper is to examine the relationship between working capital management (WCM) and firm performance in the context of the Chinese economy. Specifically, it investigates the effects of ownership structures as an internal factor and of institutional environments (IE) as an external factor shaping this relationship.

The study applies two-way fixed effect regression models to a sample of Chinese listed manufacturing firms for the period of 2010 to 2017. WCM is measured by cash conversion cycles (CCC); profitability is measured by core profit ratios; ownership structures are classified based on state-owned enterprises (SOEs) and non-SOEs; and IEs are measured from dimensions of factor markets (FM) and legal systems (LS).

First, the results show a negative relationship between CCC and firm performance. Second, the negative relationship between CCC and profitability is significant for non-SOEs but not for SOEs. Third, both the FM and LS strengthen the negative association between CCC and profitability. Fourth, the moderating effect of FMs and LSs is evident for non-SOEs only. The results hold when using alternative measures of WCM and profitability and while controlling for additional variables.

The current study shows that while WCM has a significant effect on the profitability of Chinese firms, such an effect greatly depends on the ownership structures and IE involved. The results thus offer important implications in helping the Chinese government create better IEs and in allowing manufacturing firms to improve upon their WCM practices.

The purpose of this study is to prepare a robust superhydrophobic coating on concrete substrate with remarkable chemical and mechanical durability through “all-covalent” strategy.

Amino-modified silica nano/micro-particles were prepared through two synthetic steps. “All-covalent” strategy was introduced to prepare a robust superhydrophobic coating on concrete surface via a “all-in-one” dispersion and a simple spraying method. The successful construction of the products was confirmed by Fourier transform infrared spectroscopy, water contact angles (WCA), X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM). The concrete protective properties were verified by solution immersion test, pull-off test and rapid chloride migration coefficient test. The mechanical durability was tested by falling sand impact.

Hierarchical structures combined with the low-surface-energy segments lead to typically superhydrophobic coating with a WCA of 156° and a sliding angle of 1.3°. The superhydrophobic coating prepared through “all-covalent” strategy not only improves chemical and mechanical durability but also achieves higher corrosion and wear resistance than the comparison sample prepared by physically blending strategy. More importantly, the robust superhydrophobic coating showed excellent adhesion and protective performance of concrete engineerings.

This new “all-covalent” superhydrophobic coating could be applied as a concrete protective layer with properties of self-cleaning, anti-graffiti, etc.

Introduction of both silica nanoparticles and silica microparticles to prepare a robust superhydrophobic coating on concrete surface through “all-covalent” strategy has not been systematically studied previously.