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The purpose of this study is to explore the mechanism of branch pits and tunnels formation and increase the specific surface area and capacitance of anode Al foil for high voltage electrolytic capacitor by D.C. etching in acidic solution and neutral.

Al foil was first D.C. etched in HCl-H₂SO₄ mixed acidic solution to form main tunnels perpendicular to the Al surface, and then D.C. etched in neutral NaCl solution including 0.5 per cent C₆H₈O₇ and Cu(NO₃)₂ with different concentration to form branch tunnels normal to Al surface. Between two etching, Cu nuclei were electroless deposited on the interior surface of main tunnels by natural occluded corrosion cell effect to form micro Cu-Al galvanic local cells. The effects of electroless deposited Cu nuclei on cross-section etching morphologies and electrochemical behavior of Al foil was investigated with SEM, polarization curve and electrochemical impedance spectroscopy (EIS).

The results show that sub branch tunnels can form along the main tunnels owing to the formation of Cu-Al micro-batteries, in which Cu is cathode and Al is anode. With increase in Cu(NO₃)₂ concentration, more Cu nuclei can be electroless deposited and serve as the favorable sites for branch tunnel initiation along the whole length of main tunnels, leading to enhancement in specific capacitance of anode Al foil.

Cu nuclei were electroless deposited on the interior surface of main tunnels by natural occluded corrosion cell effect to form micro Cu-Al galvanic local cells, which can serve as the favorable sites for branch tunnel initiation along the main tunnels to enhance specific capacitance of anode Al foil.

Customer value co-creation in robots-mediated hospitality encounters involves active collaboration between customers and robots. In such encounters, robot capabilities, which are their functionalities or operational competences, and robot personalities, which are their interactive behaviors and communication styles, play a key role in enhancing customer value co-creation. The purpose of this study is to draw on service dominant logic to examine the role of robot capabilities and personalities in determining customer value co-creation and service satisfaction.

The authors adopted a mixed-methods research approach. A netnographic analysis was conducted on online customer reviews for robotic hotels and restaurants to identify key robot capabilities that shaped the customer experiences. Following this, a quantitative study (survey) was conducted to investigate the effects of robot capabilities and personalities on customer value co-creation and service satisfaction.

From the netnographic analysis, the authors identified cognitive, technical, interactional, emotional, personalization and autonomous capabilities as key robot capabilities influencing customer experiences. The findings of the follow-up empirical study showed that the higher-order robot capabilities construct positively influences customer value co-creation, which, in turn, affects service satisfaction. Furthermore, extroversion robot personality positively moderates this relationship, such that robots with high levels of capabilities result in greater value co-creation when robots possess extroversion personalities compared to introversion personalities.

This study advances the understanding of robot-mediated encounters by emphasizing the role of robot capabilities and personalities as crucial factors for effective customer value co-creation in the hospitality sector. Furthermore, it offers actionable insights for hospitality providers in selection of robots with key capabilities and personalities for enhancing customer satisfaction and successful value co-creation.

While previous research has predominantly focused on customer acceptance of and interaction with robots in the hospitality settings, the present study examined how and when service robots facilitate value co-creation with customers. Specifically, this study explores robot capabilities and personalities in shaping customer value co-creation perceptions. A few recent studies that examined customer-robot interactions have considered specific robot capabilities. However, given that hospitality services are experiential in nature and involve various tasks, a broad range of robot capabilities should be considered for a comprehensive understanding of the customer value co-creation process. By addressing this gap, the present study offers novel insights into what (capabilities) and how (extraversion personality) service robots facilitate customers in value co-creation and satisfaction.

The purpose of this paper is to investigate the effects of load and speed on the corrosive wear performance of Al coating in 3.5% NaCl solution, which provided an experimental reference for the anti-corrosion engineering on offshore platforms.

A layer of Al coating was prepared on S355 steel using an arc spraying. The corrosive wear test was carried out with CFT–1 type surface property tester. The effects of load and speed on the corrosive wear performance of Al coating were investigated and the wear mechanism was also discussed. The electrochemical tests were conducted using a CHI660E type electrochemical workstation, the anti-corrosion mechanism was analyzed.

The average coefficient of frictions (COFs) of Al coating under loads of 1.5, 2.5 and 3.5 N are 0.745, 0.847 and 0.423, the wear mechanism is abrasive wear. The average COFs of Al coating at the speeds of 200, 400 and 600 rpm are 0.745, 0.878 and 0.617, respectively, the wear mechanism at the speeds of 200 and 400 rpm are abrasive wear, while that at the speed of 600 rpm is abrasive wear and fatigue wear. The anti-corrosion mechanism is the isolation of Cl^– corrosion and cathodic protection of sacrificial anode.

This paper mainly studied corrosive wear and electrochemical corrosion performances of Al coating. This study hereby confirms that this manuscript is the original work and has not been published nor has it been submitted simultaneously elsewhere. This paper further confirms that all authors have checked the manuscript and have agreed to the submission.

This paper aims to understand the process of guest-robot value co-creation in the restaurant context. It empirically examines the guest perception of value facilitation by service robots and its impact on guest value co-creation and advocacy intentions. It also investigates the moderating role of interaction comfort in the relationship between service robot value facilitation and guest value co-creation.

A mixed-methods approach was adopted. Ten customers who had dined at a service robot restaurant in China were interviewed in the qualitative study, followed by a quantitative study with 252 restaurant patrons to test the relationships between service robot value facilitation, guest value co-creation, interaction comfort and advocacy intentions.

Guest perceptions of six robot attributes, including role significance, competence, social presence, warmth, autonomy and adaptability, determine service robot value facilitation. Interaction comfort moderates the influence of service robot value facilitation on guest value co-creation. Additionally, guest value co-creation mediates the effect of service robot value facilitation on advocacy intentions.

This study offers an understanding of six robot attributes that can improve service robot value facilitation. Nevertheless, the authors collected data from guests who had experience at service robot restaurants. The authors encourage future research to use random sampling methods to ensure study representativeness.

This study offers strategic guidance for managers to deploy service robots in frontline roles in restaurants and provides important implications for service robot design to improve their facilitating role in the guest value co-creation process.

This study responds to a recent call for research on the role of service robots in the guest value co-creation experience. Unlike prior studies that focused on the adoption or acceptance of service robots, it examines the role of service robots in the value co-creation process (post-adoption stage). Furthermore, it is one of the early studies to identify and empirically examine the service robot attributes that enable value facilitation and foster value co-creation in guest-robot service encounters.

This chapter aims to investigate and interpret China’s educational aid by analyzing its history, philosophies, and practices in Africa. The study is based on review and analysis of governmental documents, reports, academic papers, and news by Chinese and foreign scholars on China’s aid, particularly educational aid to Africa. The analysis unveils three transformations of China’s aid “from pro-ideology to de-ideology,” “from single area to multiple areas,” and “from pragmatic economy driven to sustainable and humane economy focused” in Africa. Meanwhile, it indicates a continuity of the philosophy of solidarity, morality, and reciprocity in China’s South-South cooperation with African educational development.

The analysis also shows China’s educational aid does not match well with the framework of the Western donors. China, under the FOCAC framework, is devoted to higher education cooperation, human resources training program, scholarship, and Chinese language education with African partners. With the growth of its economic and political influence, China will play multiple roles as the biggest developing country and as an active promoter and provider for South-South cooperation in the negotiation and construction of the post-2015 agenda. Nevertheless, we assume China will keep a pragmatic higher education cooperation with its developing country partners to inclusively link it with business, technology transfer, and people-to-people exchange.

This study delivers a comprehensive review and analysis of paradigm shift, philosophy, mechanism, and practice of China’s educational aid to Africa to fill up the literature gap in this field. It also timely presents China’s stance toward discussion on the post-2015 agenda.

This paper aims to obtain rare earth magnesium alloy with good adhesion and corrosion resistance.

In 353 K oil bath, cyclic voltammetry was used to study the electrochemical behavior of Pr(III), Mg(II) and Ni(II) in choline chloride-urea ionic liquid. The constant potential method was adopted for electrodeposition of Pr-Mg-Ni ternary alloy films. The content of Pr in the Pr-Mg-Ni alloy films changes with respect to the deposition potential, deposition time and concentration ratio of Pr³⁺:Mg²⁺:Ni²⁺. Response surface methodology was applied to optimize the conditions for obtaining high-quality deposition films.

The results showed that the reaction of Ni(II) to Ni is irreversible; this result can be verified by Tafel polarization curve and chronocoulometry curve. Its transfer coefficient on the platinum electrode of 0.32 and diffusion coefficient is 1.0510⁻⁶ cm².s⁻¹. Mg(II) and Pr(III) cannot solely be reduced to their elemental form, but they can be induced via codeposition by Ni(II). The result shows that under a voltage of −1.00 V, the alloy coating with even structure is obtained when the concentration ratio of Pr³⁺:Mg²⁺:Ni²⁺ is 1:1:1 and the deposition time is 20 min. Scanning electron microscopy, X-ray diffraction, energy-dispersive X-ray spectroscopy and other analyses revealed that the alloy coating is amorphous. Polarization curves of the cathode are tested, which manifest the lowest corrosion current density, stating which has good corrosion performance in alkaline solution and NaCl solution; this can be attributed to its dense film structure and good combination with the substrate.

It provides some technology for the production of corrosion-resistant materials.

This paper intends to provide a thematic literature review of the scholarly research articles orbiting the Sino–African education cooperation and exchange, published between 2005 and 2022.

The methodology used in this paper is qualitative in nature with a thematic approach. The author used content analysis techniques to spotlight the major themes of the topic studied. The author selected the papers and theses, based on their heuristic capacity, from two major databases for the English and Chinese literature: Web of Science and CNKI. The selection process resulted in 60 high-quality peer-reviewed articles and theses. Another 30 research articles and theses were used as supplementary resources.

The literature concentrates on six points: the historical development, the nature of the exchange, the frameworks of the cooperation, vocational training and knowledge transfer, African students in China and their experiences, and education cooperation and soft power. However, research tends to be somewhat polemical rather than an academic debate between Chinese researchers and their western peers. Therefore, empirical studies beyond the geopolitical preoccupations and the “YEA” or “NAY” to the Sino–African education exchange are critically needed.

The implications of this study go beyond the east/west or developed/developing world rhetoric and focus more on sustainable educational development on a global scale. Understanding how the literature on the Sino–African education engagement is shaping, provides valuable insights into international education in the global south. It can also be implied to approach educational engagement with other destinations such as India, Türkiye and Brazil.

This thematic literature review concentrates on the educational aspect of Sino–African relations. It compares English and Chinese peer-reviewed scholarly articles and theses on China–Africa educational engagement and has heuristic implications for sustainable educational development globally.

The purpose of this paper is to study the effect of nano polypyrrole-modified boron nitride on the performance of phosphate film.

By adding polypyrrole-modified boron nitride to the phosphate solution, a phosphate film is formed on the metal surface, improving its corrosion resistance. The effect of different concentrations of polypyrrole-modified boron nitride on the corrosion resistance of Q235 carbon steel surface was studied. The corrosion resistance of the phosphate film was evaluated using the copper sulfate drop test. The electrochemical corrosion performance of the phosphate film was assessed using the weak polarization curve method and electrochemical impedance spectroscopy. The surface of the samples was characterized using scanning electron microscopy and X-ray diffraction analysis.

The results show that samples containing polypyrrole-modified boron nitride have a denser and more uniform phosphate film. When the concentration of polypyrrole-modified boron nitride is 0.6 g/L, the drop time of copper sulfate on the formed phosphate film can reach 219 s, which is a 189% increase compared to the performance of the sample without the additive. The current density is 1.06 × 10⁻⁶ A/cm² lower than that of the pure phosphate film, indicating the best corrosion resistance. Polypyrrole-modified boron nitride effectively promotes the formation of the phosphate film.

This study used the modification of phosphate solution using nanoparticles to investigate the influence of different nanoparticle concentrations on the phosphate film. The corrosion resistance of the phosphate film was enhanced, providing a method and theoretical guidance for the improvement of phosphate solution formulation.

This paper aims to feature preparation and characterization of thiokol oligomer functionalized MWCNTs/epoxy nanocomposites using low molecular weight polyamide as curing agent.

First, thiokol oligomer functionalized MWCNTs (MWCNTs-TO) were prepared through hydroxylation, silanization and graft modification of MWCNTs. The nanocomposite specimens were fabricated through sonication and cast moulding process. The authors then investigated the impact of MWCNTs-TO content on mechanical and thermal properties of the nanocomposites.

MWCNTs-TO with grafting ratio of 17.5 Wt.% was synthesized and characterized with X-ray photoelectron spectroscopy, thermal gravimetric analysis, Fourier transform infrared and scanning electron microscopy. The obtained epoxy nanocomposites exhibit improved mechanical properties and thermal stability with MWCNTs-TO added. Moreover, desirable results were obtained at 0.75 Wt.% of MWCNTs-TO loading: the young’s modulus, tensile, flexural and impact strength increased by 24.6,72.8,34.8 and 82.7%, respectively, compared to the neat epoxy. The improvement of mechanical properties is mainly attributed to enhanced interfacial interaction and dispersion between the covalent functionalized MWCNTs and epoxy matrix.

A flexible thiokol oligomer was successfully grafted onto MWCNTs via a mild route. Nanocomposites with excellent interfacial interaction and dispersion between MWCNTs-TO and the epoxy matrix have been successfully fabricated and investigated.

This method provided a mild and practical approach to improve the performance of MWCNTs epoxy nanocomposites.

A flexible thiokol oligomer was successfully covalent grafted onto MWCNTs via a mild route. Nanocomposites with excellent interfacial interaction and dispersion between MWCNTs-TO and the epoxy matrix have been successfully fabricated and investigated.

This work was focused upon the main factors that influence the formation of a hydroxypropyl-β-cyclodextrin (HP-β-CD) supramolecular complex with octadecylamine (ODA) and their optimal processing conditions. The anti-corrosion properties of the products in the simulated boiler water condensate of power plants also needed to be tested. The paper aims to discuss these issues.

A grinding method was applied to synthesize the supramolecular structures. Using Fourier transform infrared, X-ray diffraction and proton nuclear magnetic resonance spectroscopy (1H NMR), the specific structures of the complex were clarified. The anti-corrosion properties were obtained from gravimetric results, potentiodynamic polarization tests and electrochemical impedance spectroscopy measurements.

The results reveal the highly soluble supramolecular complex could be formed between two HP-β-CD molecules and one ODA molecule at 85°C with a processing period of 15 minutes. In the condensate, the corrosion inhibition efficiency of the complex was over 95 percent, much higher than the inhibition efficiency of the hydrophobic ODA compound.

The supramolecular corrosion inhibitor could be used as an anti-corrosion method for industrial boiler condensate to reduce the content of corrosive ions. In this way, it is easier to reuse the condensate without re-polishing.

The research introduces supramolecular chemistry into corrosion science for the first time. The results provide a new option to modify the traditional corrosion inhibitors.