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Article
Publication date: 22 June 2012

Yan Jun Xi, Yong Jun Liu, Zhi Xin Wang and Jin Bin Liu

The purpose of this paper is to investigate the oxidation behavior of Ti‐48Al‐8Cr‐2Ag (at.%) at 900°C and 1000°C for various different times.

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Abstract

Purpose

The purpose of this paper is to investigate the oxidation behavior of Ti‐48Al‐8Cr‐2Ag (at.%) at 900°C and 1000°C for various different times.

Design/methodology/approach

Laboratory tests were performed to determine growth process of the oxide scale at 900°C and 1000°C for various different times with SEM/EDX, XRD and TEM.

Findings

Merely Al2O3 occurred on the Laves phase at the initial stage at 900°C, while a mixture of Al2O3+TiO2 formed at the initial stage at 1000°C. Oxidation rate of the alloy at 900°C after long‐term oxidation was higher than that at 1000°C because a dense Al2O3 scale formed on the surface at 1000°C.

Originality/value

The paper shows that the oxidation behavior of TiAl alloy at initial stage is the basis of the revealing mechanism of oxidation. It is necessary to further investigate the oxidation of Ti‐Al‐Cr‐Ag alloy in more detail to clearly understand its oxidation process and growth process of the oxide scale.

Details

Anti-Corrosion Methods and Materials, vol. 59 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 12 January 2010

Yan Jun Xi, Yong Jun Liu, Zhi Xin Wang and Jin Bin Liu

The purpose of this paper is to investigate the high‐temperature oxidation behavior in air at 900‐1,000°C and electrochemical corrosion performance in 3.5 percent NaCl solution of…

568

Abstract

Purpose

The purpose of this paper is to investigate the high‐temperature oxidation behavior in air at 900‐1,000°C and electrochemical corrosion performance in 3.5 percent NaCl solution of Ti‐24Al‐17Nb‐0.5Mo (at. %) alloy with Ti‐48Al‐8Cr‐2Ag (at. %) coating.

Design/methodology/approach

Laboratory tests are performed to determine the effect of the Ti‐48Al‐8Cr‐2Ag (at. %) coating on the corrosion performance of Ti3Al alloy.

Findings

It is found that the oxidation rate of sputtered Ti‐48Al‐8Cr‐2Ag nanocrystalline coating is lower than that of the Ti3Al alloy at 900°C. The former forms a scale of merely Al2O3 and the latter forms a scale of TiO2. However, the Ti‐48Al‐8Cr‐2Ag nanocrystalline coating shows a slightly higher oxidation rate than did the Ti3Al alloy at 1,000°C, because outer TiO2 scale forms and columnar boundaries of the coating give a larger actual oxidation area than the original alloy. The coating shows the excellent electrochemical corrosion resistance in 3.5 percent NaCl solution because it exhibits stable passive polarization behavior without any overpassivation phenomena.

Originality/value

TiAlCrAg coatings may become a promising protective coating for Ti3Al‐base intermetallics, which improve the Al2O3 scale formation and make the passivation stable.

Details

Anti-Corrosion Methods and Materials, vol. 57 no. 1
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 16 July 2019

Yong Liu, Jun-liang Du, Ren-Shi Zhang and Jeffrey Yi-Lin Forrest

This paper aims to establish a novel three-way decisions-based grey incidence analysis clustering approach and exploit it to extract information and rules implied in panel data.

783

Abstract

Purpose

This paper aims to establish a novel three-way decisions-based grey incidence analysis clustering approach and exploit it to extract information and rules implied in panel data.

Design/methodology/approach

Because of taking on the spatiotemporal characteristics, panel data can well-describe and depict the systematic and dynamic of the decision objects. However, it is difficult for traditional panel data analysis methods to efficiently extract information and rules implied in panel data. To effectively deal with panel data clustering problem, according to the spatiotemporal characteristics of panel data, from the three dimensions of absolute amount level, increasing amount level and volatility level, the authors define the conception of the comprehensive distance between decision objects, and then construct a novel grey incidence analysis clustering approach for panel data and study its computing mechanism of threshold value by exploiting the thought and method of three-way decisions; finally, the authors take a case of the clustering problems on the regional high-tech industrialization in China to illustrate the validity and rationality of the proposed model.

Findings

The results show that the proposed model can objectively determine the threshold value of clustering and achieve the extraction of information and rules inherent in the data panel.

Practical implications

The novel model proposed in the paper can well-describe and resolve panel data clustering problem and efficiently extract information and rules implied in panel data.

Originality/value

The proposed model can deal with panel data clustering problem and realize the extraction of information and rules inherent in the data panel.

Details

Kybernetes, vol. 48 no. 9
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 25 November 2019

Song Quan, Guo Yong, Gong Jun, Xuedong Liu, Jin Yongping and Yang Shuyi

This paper aims to study the frictional performance of reciprocating pair with high velocity by using hydrodynamic lubrication principle and fish scale textured piston model.

219

Abstract

Purpose

This paper aims to study the frictional performance of reciprocating pair with high velocity by using hydrodynamic lubrication principle and fish scale textured piston model.

Design/methodology/approach

Based on the idea of function characteristic approximation and coordinate change, a mathematical representation model of imitating fish scale texture pit section is established. According to the principle of dynamic pressure lubrication of the textured fluid, a three-dimensional numerical model of flow field for fish scale texture is established without considering cavitation. Numerical analysis of the model carp scale texture unit by orthogonal experimental design and FLUENT software is carried out.

Findings

Effects of fish scale pit texture on friction properties for a reciprocating pair piston surface with high velocity (impact piston) are acquired. Effects of texture characterization parameters and flow rate on the surface friction performance for impact piston are found. Effects of different characteristic parameters combination of imitating fish scale texture on friction performance for impact piston surface are obtained.

Originality/value

The model is an effective tool to study the friction and wear of reciprocating pair with high velocity. The effects of fish scale textured piston pair supply a theory lead to design the reciprocating pair with better friction performance.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2019-0398

Details

Industrial Lubrication and Tribology, vol. 72 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 7 May 2024

Pingping Hou, Zheng Qian, Meng Xin Hu, Ji Qi Liu, Jun Zhang, Wei Zhao, Xiao Li, Yong Wang, HongYan Huang and Qian Ping Ran

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…

60

Abstract

Purpose

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.

Design/methodology/approach

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.

Findings

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.

Practical implications

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.

Originality/value

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.

Details

Pigment & Resin Technology, vol. 54 no. 3
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 25 January 2022

Jiawei Sun, Peng Yi, Hong-Yu Jia, Xiao-Shuang Yang, Yong-Jun Shi, Yancong Liu and Muming Hao

This paper aims to investigate the influence of sinusoidal texture (ST) with different morphology parameters on the corresponding tribological effects.

122

Abstract

Purpose

This paper aims to investigate the influence of sinusoidal texture (ST) with different morphology parameters on the corresponding tribological effects.

Design/methodology/approach

The STs with different amplitudes, ranging from 0.05 to 0.3 mm, and frequencies, ranging from 5 to 17.5, are fabricated using nanosecond pulsed laser equipment. The friction experiments and the finite element analysis method are combined to investigate the tribological properties, under dry friction conditions.

Findings

Test results show that when the amplitude is 0.15 mm and frequency is 10, ST surface has the lowest friction coefficient of 0.373, and exhibits great anti-friction effect. It also possesses a complete texture edge after friction. The friction reduction effect of ST with larger or smaller amplitude and frequency is worse.

Originality/value

The results of this study can provide a guidance for the design optimization of ST of reciprocating sliding contact surfaces, under dry friction conditions.

Details

Industrial Lubrication and Tribology, vol. 74 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 2 October 2017

Beom Jun Bae and Yong Jeong Yi

The purpose of this paper is to understand consumers’ preferences for answers about sexually transmitted diseases on social question and answer (Q&A) sites by employing message…

727

Abstract

Purpose

The purpose of this paper is to understand consumers’ preferences for answers about sexually transmitted diseases on social question and answer (Q&A) sites by employing message features and information sources as conceptual frameworks.

Design/methodology/approach

The study compared best answers selected by questioners with their randomly drawn counterpart non-best answers on Yahoo! Answers as a paired sample (n=180).

Findings

The findings indicate that questioners on social Q&A sites were more likely to prefer answers including message features such as numeric information, social norms, optimistic information, and loss-framing, as well as information sources that featured expertise, references, and links to other websites. Pessimistic information was negatively associated with questioners’ preference for answers.

Research limitations/implications

The study extended the discussion of consumers’ selection of best answers to message features and information sources as additional criteria.

Practical implications

The findings suggest that answerers on social Q&A sites communicate more effectively with their audiences by utilizing persuasive communication.

Social implications

There is a quality issue on social Q&A sites. The findings will be helpful for health professionals to develop answers that are more likely to be selected as best answers, which will enhance overall quality of health information on social Q&A sites.

Originality/value

Consumers’ preference criteria for health information have been investigated using many different approaches. However, no study has used a persuasion framework to examine how consumers appraise answer quality. The present study confirmed consumers’ preference criteria as found in previous social Q&A studies and extended the discussion of consumers’ perceptions of answer quality by applying the frameworks of message features and information sources.

Details

Internet Research, vol. 27 no. 5
Type: Research Article
ISSN: 1066-2243

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Article
Publication date: 10 November 2022

Sifeng Liu, Yong Tao, Naiming Xie, Liangyan Tao and Mingli Hu

The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it…

345

Abstract

Purpose

The purpose of this paper is to summarize the advances in grey system theory research and various application achievements in science and engineering. At the same time, it commemorates the 40th anniversary of the birth of grey system theory and the 10th anniversary of Grey Systems–Theory and Application.

Design/methodology/approach

Firstly, the innovations of theoretical research in grey system theory were summarized and some of the widely recognized new results are briefly described. By searching and combing the research results of grey system theory in China national knowledge infrastructure (CNKI) database and Web of Science by Institute for Scientific Information (ISI), this paper shows the rapid development trend of grey system theory in the past 40 years, and the successful applications of grey system theory in the fields of social sciences, natural sciences and engineering technologies.

Findings

More than 227 thousands literature were found by input 10 phrases such as grey system, grey number and sequence operator etc. in CNKI database. After entering the new century, the number of grey system papers included in CNKI database is increasing rapidly. Since 2008, more than 10 thousands papers have been included per year and more than 15 thousands papers have been included per year since 2014. Grey system method and model are widely used in physics, chemistry, biology and other fields of natural science, as well as transportation, electric power, machinery and other fields of engineering technology, and a large number of valuable results have been achieved.

Practical implications

It can be seen that the grey system theory plays an important role in promoting China’s scientific and technological progress, innovation and development and high-level talent training from tens of thousands of literatures marked with important national science and technology projects and a large number of grey system literatures published by China’s double first-class universities and double first-class discipline construction universities.

Originality/value

Both innovations of theoretical research and practical application play important role in the growth of new theory. The innovations of theoretical research provide methods and tools for practical application, which is conducive to improve application efficiency and broaden application fields. A large number of practical applications needs have become the source of theoretical innovation and the solid background for the birth of theoretical innovation achievements.

Details

Grey Systems: Theory and Application, vol. 12 no. 4
Type: Research Article
ISSN: 2043-9377

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Article
Publication date: 19 September 2016

Yong Jeong Yi, Soeun You and Beom Jun Bae

The purpose of this paper is to investigate the factors that influence college students’ smartphone use for academic purposes by identifying the task-technology fit (TTF) of…

4112

Abstract

Purpose

The purpose of this paper is to investigate the factors that influence college students’ smartphone use for academic purposes by identifying the task-technology fit (TTF) of smartphones. A research model is proposed to explain how TTF of smartphones affects college students’ perceived academic performance and smartphone use.

Design/methodology/approach

Online surveys were administered to college students at a South Korean university that has offered online academic services for more than five years, and 1,923 valid responses were analyzed. The study used partial least squares path modeling to evaluate the measurement model, and the bootstrapping technique to test the significance of the hypotheses.

Findings

The findings highlight that the TTF of smartphones has a direct influence on students’ perceptions of performance impact and an indirect influence on smartphone use through a precursor of utilization, such as attitude toward smartphone use, social norms and facilitating conditions.

Research limitations/implications

Despite a reasonably large sample, a single cross-sectional survey has a likelihood of selection bias in the sample.

Practical implications

This study applies the TTF model to smartphone use among college students and suggests an effective way to motivate them to use mobile technologies for their academic activities.

Originality/value

The present study develops an empirical model to assess the adoption of smartphones and its effect on college students’ academic performance. Above all, the study identifies a causal relationship among TTF, precursor of utilization, smartphone use and a perceived impact on academic performance based on the development and validation of the TTF constructs of smartphones.

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Article
Publication date: 17 August 2012

Jun Zhang, Zuqiang Liu, Yanjie Liu and Yong Liu

The purpose of this paper is to apply grey statistical model to identify and classify live fault rupture.

243

Abstract

Purpose

The purpose of this paper is to apply grey statistical model to identify and classify live fault rupture.

Design/methodology/approach

Based on grey statistical mode, this paper uses eight faults' ripping speed observation data from 1997 to 2001, according to the grey statistics method for analysis, and recognizes active fault rupture situation. Using the conventional methods, namely taking all faults monitoring stations' average dislocation rate to analysis and make judgment, the average results are obtained.

Findings

The results show that the results are closer to reality because the grey statistical evaluation method has considered dislocation rate and other discrete factors.

Practical implications

The method exposed in the paper can be used to monitor and recognize live fault rupture in earthquake prediction.

Originality/value

According to the fault dislocation rate, this paper advances active fault rupture identification and classification method based on grey statistical model.

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