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Article
Publication date: 29 November 2018

Yingjun Zhang, Xue-Jun Cui, Yawei Shao, Yanqiu Wang, Guozhe Meng, Xiu-Zhou Lin, Dongquan Zhong and Dajian Wang

This paper aims to prepare a residual rust epoxy coating by adding different quantities of phytic acid (PA) on the surface of the rusty steel and investigate the corrosion…

Abstract

Purpose

This paper aims to prepare a residual rust epoxy coating by adding different quantities of phytic acid (PA) on the surface of the rusty steel and investigate the corrosion protection of PA and its action mechanisms.

Design/methodology/approach

A residual rust epoxy coating by adding different quantities of PA was prepared on the surface of the rusty steel. The influence of PA on the corrosion resistance of epoxy-coated rusty steel was investigated by means of electrochemical impedance spectroscopy and adhesion testing.

Findings

Results indicated that PA can substantially improve the corrosion resistance of epoxy-coated rusty steel. This improvement is due to the reaction of PA with residual rust and generation of new compounds with protection properties and increased adhesive strength effects on the coating/metal interface. The coating showed better protection performance when 2 per cent PA was added.

Originality/value

Considering the structure of the active groups, PA has strong chelating capability with many metal ions and can form stable complex compounds on the surface of a metal substrate, thereby improving corrosion resistance. In recent years, PA has been reported to be useful in the conversion of coatings or as green corrosion inhibitor. To the best of the authors’ knowledge, few studies have reported the use of PA as a rust converter or residual rust coating. The present work aims to improve the corrosion resistance of residual rust epoxy coating by adding PA.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 21 September 2018

Yingjun Zhang, Baojie Dou, Yawei Shao, Xue-Jun Cui, Yanqiu Wang, Guozhe Meng and Xiu-Zhou Lin

This paper aim to investigate the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments, and interpret the inhibition…

Abstract

Purpose

This paper aim to investigate the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments, and interpret the inhibition mechanism of PA on the steel with different surface treatments.

Design/methodology/approach

The influence of PA on the corrosion behavior of blast cleaned or rusty steel was investigated by means of electrochemical impedance spectroscopy (EIS). The EIS data were analyzed using the @ZsimpWin commercial software. The morphology and component of steel after immersion were characterized by scanning electron microscopy (SEM), energy dispersive spectrometer (EDS), Fourier transformation infrared (FTIR) and X-ray diffractometer (XRD).

Findings

EIS analysis results indicated that PA had good corrosion inhibition for blast cleaned or rusty steel. SEM, EDS, FTIR and XRD further indicated that PA had two main corrosion inhibition processes for the corrosion inhibition of blast cleaned or rusty steel: corrosion dissolution and formation of protective barrier layers.

Originality/value

Most published works focus the attention only toward the effect of corrosion inhibitor for the clean metal surfaces. However, the surface condition of metal sometimes is unsatisfactory in the practical application of corrosion inhibitor, such as existing residual rust. Some studies also have shown that several corrosion inhibitors could be applied on partially rusted substrates. These inhibitors mainly include tannins and phosphoric acid, but not PA. Therefore, the authors investigated the influence of PA on the corrosion behavior of carbon steel with blast cleaned or pre-rusted treatments in this paper.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 3 January 2017

Yingjun Zhang, Yawei Shao, Qiumei Shi, Yanqiu Wang, Guozhe Meng and Ping Li

The purpose of this paper was to research the influence of polyaniline/montmorillonite (PANI/OMMT) composite powder content on the corrosion protection of epoxy (EP) coating.

Abstract

Purpose

The purpose of this paper was to research the influence of polyaniline/montmorillonite (PANI/OMMT) composite powder content on the corrosion protection of epoxy (EP) coating.

Design/methodology/approach

The polyaniline/montmorillonite/epoxy (PANI/OMMT/EP) coatings containing different contents of PANI/OMMT composite powder were prepared on steel. The corrosion protection performances of PANI/OMMT/EP coatings in 3.5 per cent NaCl solutions were investigated by electrochemical impedance spectroscopy. The barrier property of coatings was examined using water absorption analysis. The structure and crosslink density of coatings were examined using scanning electron microscopy and differential scanning calorimetry, respectively.

Findings

The PANI/OMMT composite powder could enhance the barrier properties of the EP coating and reduce the corrosion rate of the steel beneath the coating. The coating showed the best corrosion protection performance when 3 per cent PANI/OMMT powder was added to the coating.

Originality/value

The research clarified the influence of PANI/OMMT content on the corrosion protection of coating from two aspects: one is the barrier performance of the coating; the other is the corrosion inhibitors for metal substrate.

Details

Anti-Corrosion Methods and Materials, vol. 64 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 12 June 2019

Xuhui Li, Yanqiu Wu, Xiaoguang Wang, Tieyun Qian and Liang Hong

The purpose of this paper is to explore a semantics representation framework for narrative images, conforming to the image-interpretation process.

Abstract

Purpose

The purpose of this paper is to explore a semantics representation framework for narrative images, conforming to the image-interpretation process.

Design/methodology/approach

This paper explores the essential features of semantics evolution in the process of narrative images interpretation. It proposes a novel semantics representation framework, ESImage (evolution semantics of image) for narrative images. ESImage adopts a hierarchical architecture to progressively organize the semantic information in images, enabling the evolutionary interpretation under the support of a graph-based semantics data model. Also, the study shows the feasibility of this framework by addressing the issues of typical semantics representation with the scenario of the Dunhuang fresco.

Findings

The process of image interpretation mainly concerns three issues: bottom-up description, the multi-faceted semantics representation and the top-down semantics complementation. ESImage can provide a comprehensive solution for narrative image semantics representation by addressing the major issues based on the semantics evolution mechanisms of the graph-based semantics data model.

Research limitations/implications

ESImage needs to be combined with machine learning to meet the requirements of automatic annotation and semantics interpretation of large-scale image resources.

Originality/value

This paper sorts out the characteristics of the gradual interpretation of narrative images and has discussed the major issues in its semantics representation. Also, it proposes the semantic framework ESImage which deploys a flexible and sound mechanism to represent the semantic information of narrative images.

Details

The Electronic Library , vol. 37 no. 3
Type: Research Article
ISSN: 0264-0473

Keywords

Article
Publication date: 14 September 2018

Yongqiang Sun, Yan Zhang, Xiao-Liang Shen, Nan Wang, Xi Zhang and Yanqiu Wu

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…

2023

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Originality/value

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.

Details

Aslib Journal of Information Management, vol. 70 no. 5
Type: Research Article
ISSN: 2050-3806

Keywords

Article
Publication date: 27 November 2020

Mingwei Lin, Yanqiu Chen and Riqing Chen

The purpose of this paper is to make a comprehensive analysis of 354 publications about Pythagorean fuzzy sets (PFSs) from 2013 to 2020 in order to comprehensively…

Abstract

Purpose

The purpose of this paper is to make a comprehensive analysis of 354 publications about Pythagorean fuzzy sets (PFSs) from 2013 to 2020 in order to comprehensively understand their historical progress and current situation, as well as future development trend.

Design/methodology/approach

First, this paper describes the fundamental information of these publications on PFSs, including their data information, annual trend and prediction and basic features. Second, the most productive and influential authors, countries/regions, institutions and the most cited documents are presented in the form of evaluation indicators. Third, with the help of VOSviewer software, the visualization analysis is conducted to show the development status of PFSs publications at the level of authors, countries/regions, institutions and keywords. Finally, the burst detection of keywords, timezone review and timeline review are exported from CiteSpace software to analyze the hotspots and development trend on PFSs.

Findings

The annual PFSs publications present a quickly increasing trend. The most productive author is Wei Guiwu (China). Wei Guiwu and Wei Cun have the strongest cooperative relationship.

Research limitations/implications

The implication of this study is to provide a comprehensive perspective for the scholars who take a fancy to PFSs, and it is valuable for scholars to grasp the hotspots in this field in time.

Originality/value

It is the first paper that uses the bibliometric analysis to comprehensively analyze the publications on PFSs. It can help the scholars in the field of PFSs to quickly understand the development status and trend of PFSs.

Details

International Journal of Intelligent Computing and Cybernetics, vol. 14 no. 2
Type: Research Article
ISSN: 1756-378X

Keywords

Article
Publication date: 16 February 2022

Yuanwei Liu, Bin Wang, Yan Xie, Yu Chen, Zhongnian Yang, Guojun Han and Yanqiu Dang

The purpose of this paper is to prepare a dual-encapsulated halloysite nano-container to release the capsuled inhibitor as an additive for corrosion protection of epoxy coating.

Abstract

Purpose

The purpose of this paper is to prepare a dual-encapsulated halloysite nano-container to release the capsuled inhibitor as an additive for corrosion protection of epoxy coating.

Design/methodology/approach

Halloysite nano-containers (HNT) were prepared by simultaneously implanting inhibitor benzotriazole (BTA) into the inside and outside of the halloysite using reduced pressure and layer-by-layer (LBL) assembly, respectively. The microstructure and morphology of treated HNT were investigated using Fourier transform infrared spectroscopy and transmission electron microscopy. In addition, the anti-corrosion behaviors of the composite polyepoxy coating with inhibitor-loaded nano-containers BTA@HNT-2 were investigated using the electrochemical impedance spectroscopy and neutral salt spray test.

Findings

Test results showed that the LBL assembly structure of the halloysite nano-container makes the BTA@HNT-2 nano-container be controlled and sustained to release BTA, relying on the pH. Very importantly, the obtained nano-container is also responsive to temperature, owing to the thermosensitivity polyelectrolyte out-shell of the HNT. The result showed Rct of the composite polyepoxy coating can be sufficient to maintain higher than 8.510E+7 Ω·cm2 over 72 h of immersion test. Moreover, the artificial induced defects on the coating surface were sufficiently inhibited in the presence of BTA@HNT-2 nano-container in the polyepoxy coating.

Originality/value

Use of the BTA@HNT-2 as corrosion inhibitor nano-container, with good anti-corrosion property and dual-responsive to pH and temperature, offers a significant rout to prepare smart anti-corrosion coating for protecting metal substrate.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 8 August 2016

Zhengfeng Cao, Yanqiu Xia and Xiangyu Ge

The purpose of this paper is to synthesize a new kind of conductive grease which possesses a prominent conductive capacity and good tribological properties.

Abstract

Purpose

The purpose of this paper is to synthesize a new kind of conductive grease which possesses a prominent conductive capacity and good tribological properties.

Design/methodology/approach

A two-step method was used to prepare complex lithium-based grease. Ketjen black (KB), acetylene black (AB) and carbon black (CB) were characterized by transmission electron microscope and used as lubricant additives to prepare conductive greases. Conductive capacity was evaluated by a conductivity meter, a surface volume resistivity meter and a circuit resistance meter. Tribological properties were investigated by a reciprocating friction and wear tester (MFT-R4000). The worn surfaces were analyzed by a scanning electron microscope, Raman spectroscopy, energy-dispersive X-ray spectroscopy and X-ray photoelectron spectroscope.

Findings

The conductive grease prepared with KB has a prominent conductive capacity at room temperature, 100°C and 150°C. Further, this conductive grease also possesses better tribological properties than AB and KB greases. When the concentration of KB is 1.8 Wt.%, the coefficient of friction and wear width reduced by 11 and 14 per cent, respectively.

Originality/value

This work is a new application of nanometer KB as a lubricant additive in grease, which provides a direction for preparing conductive grease. The conductivity and tribology experiments have been carried out though the variation of experiment conductions.

Details

Industrial Lubrication and Tribology, vol. 68 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 8 April 2014

Yanqiu Xia, Zhihong Wang and Yanxin Song

The aim of the present paper is that three long-chain hydroxyethyl alkylimidazolium hexafluorophosphate ionic liquids (ILs) were synthesized and evaluated as lubricants for…

Abstract

Purpose

The aim of the present paper is that three long-chain hydroxyethyl alkylimidazolium hexafluorophosphate ionic liquids (ILs) were synthesized and evaluated as lubricants for steel-steel contacts at room temperature and boundary lubrication conditions. Hydroxyethyl functional group and alkyl chain length effect on the physicochemical and fretting tribological behaviors of the ILs was comparatively investigated, as compared to traditional dialkylimidazolium ILs.

Design/methodology/approach

The fretting friction and wear tests were carried out using an Optimol SRV-IV oscillating reciprocating friction and wear tester. The worn surface was observed and analyzed by scanning electron microscope and X-ray photoelectron spectroscopy. The electrochemical corrosion behavior of copper disks in selected imidazolium-based ionic liquids was studied using a CHI660B electrochemical workstation.

Findings

This can be seen by comparing the results for the non-hydroxyl ILs and hydroxyl ILs that the latter exhibited the littler friction coefficient, the smaller wear volume, although the latter electrochemical corrosion behavior of copper disks is slightly higher than the former. The results also revealed that the ILs with a longer alkyl chain displayed larger viscosities, better anti-corrosion capacities, higher hydrophobic properties and more excellent friction-reducing and anti-wear performance than those with a shorter alkyl chain.

Originality/value

This work might offer new knowledge in the design and application of new ILs as lubricants; it also confirms some in-depth physicochemical questions, e.g. the function mechanism, the correlations between structure and performance. Additionally, a proposed interaction model between the ILs and the friction substrate has been given.

Details

Industrial Lubrication and Tribology, vol. 66 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 21 October 2013

Yingxin Zhao, Yanqiu Lu and Xiangyang Wang

The purpose of this paper is to propose a model to explore the dynamic process of knowledge management from the perspectives of organizational unlearning and

3685

Abstract

Purpose

The purpose of this paper is to propose a model to explore the dynamic process of knowledge management from the perspectives of organizational unlearning and organizational relearning, which promote a favorable context for knowledge management.

Design/methodology/approach

The model is proposed based on extensive review of literatures. According to this model, the evolutions of organizational unlearning and organizational relearning are separately analyzed, and the interactions between them are revealed.

Findings

Organizational unlearning and organizational relearning are the indispensable factors to the dynamic knowledge management. Organizational unlearning positively affects the dynamic knowledge management by discarding the outdated and useless knowledge, while organizational relearning has a positive influence on the dynamic knowledge management by acquiring the new knowledge. Organizational unlearning and organizational relearning have synergies on the dynamic knowledge management.

Research limitations/implications

This paper theoretically illuminates the relationships among organizational unlearning, organizational relearning and knowledge management, and doesn't offer an empirical test.

Practical implications

This paper will provide insights to practitioners to better understand the dynamic process of knowledge management. The practitioners need to provide favorable context to ensure that organizational unlearning and organizational relearning can occur.

Originality/value

Most existing studies focused on the inflows of knowledge, but the outflows of knowledge still lack sufficient attention, especially the dynamic process of knowledge management. The framework provides guides in that process.

Details

Journal of Knowledge Management, vol. 17 no. 6
Type: Research Article
ISSN: 1367-3270

Keywords

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