Gu Xin, Xiao-Ri Liu, Dong-Kang Cheng, Qing-Ping Zheng, Meng-Han Li, Nan-Nan Sun and Chun-Hua Min
This paper aims to investigate the effect of lubricant viscosity model with improver on friction and lubrication of piston skirt-cylinder liner conjunction.
Abstract
Purpose
This paper aims to investigate the effect of lubricant viscosity model with improver on friction and lubrication of piston skirt-cylinder liner conjunction.
Design/methodology/approach
A dynamic calculation model is established for the piston skirt-cylinder liner conjunction of a heavy-duty commercial diesel engine, to explore the effects of two kinds of lube oil viscosity models named after polyalkyle-metacrylate-1 (PAMA1) and styrene-isoprene-copolymer (SICP) improvers on the maximum oil film viscosity, the minimum oil film thickness, the peak oil film pressure, the maximum shear rate, the friction force and the total friction power loss.
Findings
The variation trends with the crank angle of the above parameters are not changed with the difference of improvers, while obvious numerical differences are found except the maximum oil film pressure. The minimum oil film thickness and maximum shear rate of PAMA1 are larger than that of SICP, the maximum oil film viscosity of SICP is larger than that of PAMA1, which indicates that the shear-thinning effect of PAMA1 is greater, the maximum friction force on the piston of SICP is larger than that of PAMA1, and the total friction power consumption is also larger, the average friction power consumptions of SICP and PAMA1 are 385.4 and 262.8 W, respectively, with the relative difference of 31.8 per cent.
Originality/value
The influence of different lubricating oil additive models on the lubrication and friction of piston skirt-cylinder liner conjunction is simulated and analyzed.
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Nan Sun, Beibei Tan, Bolun Sun, Jinjie Zhang, Chao Li and Wenge Yang
Sargassum fusiforme is a popular edible seaweed in coastal cities of China that contains diverse nutrients including iodine. Cooking is an effective way to improve food safety…
Abstract
Purpose
Sargassum fusiforme is a popular edible seaweed in coastal cities of China that contains diverse nutrients including iodine. Cooking is an effective way to improve food safety, but it can alter both the contents of elements along with speciation and bioavailability. Three common cooking methods, the soaking, steaming and boiling, were evaluated for their effects on the protein structures, protein digestibility, iodine content and iodine bioavailability of S. fusiforme.
Design/methodology/approach
Fourier transform infrared spectroscopy was used to study the structural changes of protein, and an in vitro digestion/Caco-2 cell culture system was used to evaluate the digestibility of protein, bioaccessibility and bioavailability of iodine.
Findings
Boiling and steaming altered the protein secondary structure demonstrated by increased a-helix and random coil and decreased β-sheet, which improved the in vitro protein digestibility. Iodine content was reduced by cooking, with the highest loss observed after boiling, followed by soaking and steaming, while it was found that both bioaccessibility and cellular uptake of iodine were significantly elevated by boiling and steaming using an in vitro digestion/Caco-2 cell culture system. The presence of ascorbic acid, citric acid or tyrosine was beneficial for the iodine absorption, while oxalic acid and phytic acid hindered the iodine bioavailability.
Originality/value
The present finding suggested that cooking was conducive to the digestion and absorption of iodine in S. fusiforme. In addition, different dietary factors could have a certain impact on the absorption of iodine. Results of the study are essential for improving the application value of S. fusiforme to ensure reasonable consumption of seaweeds.
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Haobo Yu, Zimo Li, Yeyin Xia, Yameng Qi, Yingchao Li, Qiaoping Liu and Changfeng Chen
This paper aims to investigate the anti-biocorrosion performance and mechanism of the Cu-bearing carbon steel in the environment containing sulfate-reducing bacterial (SRB).
Abstract
Purpose
This paper aims to investigate the anti-biocorrosion performance and mechanism of the Cu-bearing carbon steel in the environment containing sulfate-reducing bacterial (SRB).
Design/methodology/approach
The biocorrosion behavior of specimens with Cu concentration of 0 Wt.%, 0.1 Wt.%, 0.3 Wt.% and 0.6 Wt.% were investigated by immersion test in SRB solution. By examining the prepared cross-section of the biofilm using focused ion beam microscopy, SRB distribution, bacterial morphology, biofilm structure and composition were determined. The ion selectivity of the biofilm was also obtained by membrane potential measurement. Moreover, the anti-biocorrosion performance of the Cu-bearing carbon steel pipeline was tested in a shale gas field in Chongqing, China.
Findings
Both the results of the laboratory test and shale gas field test indicate that Cu-bearing carbon steel possesses obvious resistance to microbiologically influenced corrosion (MIC). The SRB, corrosion rate and pitting depth decreased dramatically with Cu concentration in the substrate. The local acidification caused by hydrolyze of ferric ion coming from SRB metabolism and furtherly aggravated by anion selectivity biofilm promoted the pitting corrosion. Anti-biocorrosion of Cu-bearing carbon steel was attributed to the accumulation of Cu compounds in the biofilm and the weaker anion selectivity of the biofilm. This research results provide an approach to the development of economical antibacterial metallic material.
Originality/value
MIC occurs extensively and has become one of the most frequent reasons for corrosion-induced failure in the oil and gas industry. In this study, Cu-bearing carbon steel was obtained by Cu addition in carbon steel and possessed excellent anti-biocorrosion property both in the laboratory and shale gas field. This study provides an approach to the development of an economical antibacterial carbon steel pipeline to resist MIC.
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Seungjong Sun, Jang Hyun Kim, Kwan Min Lee and Dongyan Nan
Massive multiplayer online role-playing games (MMORPGs) are representative metaverse games that are thriving in academia and the industry. This study aims to develop an integrated…
Abstract
Purpose
Massive multiplayer online role-playing games (MMORPGs) are representative metaverse games that are thriving in academia and the industry. This study aims to develop an integrated model based on Yee's motivations and the Proteus effect to explore individuals' intentions of playing MMORPGs.
Design/methodology/approach
The data were gathered by conducting an online survey (n = 441) for the players of World of Warcraft, an MMORPG. The collected data were analyzed with a structural equation model.
Findings
The outcomes of this research reveal that the Proteus effect positively influenced the intentions of the players to play the game via mediations of social, immersion, achievement motivations and enjoyment. Furthermore, the players influenced by the Proteus effect, which enables avatar embodiment and identification, exhibited a stronger intention to play MMORPGs.
Originality/value
This research is one of the first attempts to establish a theoretical framework involving the Proteus effect and Yee's motivations. In addition, the findings of this study imply that the Proteus effect should be considered when investigating the individual experience of metaverse games.
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Fu-Wang Yang, Jiang-Min Huang, Guan-Jun Zhang, Chenxi Zhang, Dong-Lan Sun, Nan-Feng Gao and Shouzhi Yi
The phosphorus and zinc contained in zinc dialkyl dithiophosphate (ZDDP) caused severe environment pollution and catalyst poison. Thus, the phosphorus-free additive, such as…
Abstract
Purpose
The phosphorus and zinc contained in zinc dialkyl dithiophosphate (ZDDP) caused severe environment pollution and catalyst poison. Thus, the phosphorus-free additive, such as borate esters, has become one of studying hot topics in the area of oil additive. However, the stability of hydrolysis greatly limited the use of borate esters. The purpose of this paper is to improve the stability of hydrolysis by synthesizing a new kind of N-containing heterocyclic borate ester (MTTDB) as a lubricant additive.
Design/methodology/approach
The tribological properties of novel borate ester (MTTDB) as an additive in the base oil were studied by a four-ball machine. The element composition and chemical state of the tribofilm were investigated by scanning electron microscopy, energy dispersive spectrometer and X-ray photoelectron spectroscopy.
Findings
The results showed that the base oil lubricated by MTTDB exhibited high hydrolytic stability, good anti-wear property and excellent extreme pressure performance. When 2.5 per cent MTTDB was added into the 100N base oil, the smallest wear scar diameter (0.46 mm) was obtained. Furthermore, the decomposed borate ester, organic sulfide adsorbed on the worn surface was detected, and S element reacted with the steel surface and generated FeSO4, both of which contributed to the formation of the tribofilm.
Originality/value
Based on N-containing heterocyclic compounds, for instance, thiadiazole derivatives, introducing nitrogen and sulfur elements into borate ester, a new kind of N-containing heterocyclic borate ester (MTTDB) exhibited excellent property in hydrolysis stability, friction-reducing, anti-wear and extreme pressure. This synthesized method would be helpful for the borate ester used as additive in engine oil, gear oil and other industrial lubricants.
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Xiaofeng Yang and Xiaoping Chu
The purpose of this paper is to investigate the relationship between team leader's people value and team effectiveness based on social identity theory. This paper focuses on how…
Abstract
Purpose
The purpose of this paper is to investigate the relationship between team leader's people value and team effectiveness based on social identity theory. This paper focuses on how team leader's people value affects team effectiveness in the Chinese context. It also examines the mediating effect of leader identification between leader's people value and team effectiveness.
Design/methodology/approach
A literature review on people value, leader identification and team effectiveness provided the authors' model and hypothesis. Using a sample of 64 teams with 386 employees and 64 team leaders from ten companies, hierarchical regression was conducted to test the hypothesis.
Findings
The findings suggest that follower's identification with leader is an important way to understand leader's people value for employees in encouraging employees to strive for team effectiveness. Leaders in teams should pay special attention to their people value for employees.
Research limitations/implications
The data are self‐reported and subject to biases, and may not be accurate, Both the scales of leader identification and team effectiveness were developed in western countries, and they may not capture the full meaning in China. Cross‐sectional data were used in this study; future research should use a longitudinal design to prove the direction of causality among the contracts.
Originality/value
This paper is original in its investigation on how leader's people value influences team effectiveness, through the mediation of leader identification at team level in a Chinese context.
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Assembly cost is one of the major contributing factors in the totalmanufacturing cost equation. It has been estimated, particularly in themechanical and electrical industries…
Abstract
Assembly cost is one of the major contributing factors in the total manufacturing cost equation. It has been estimated, particularly in the mechanical and electrical industries, that assembly costs can account for over 50 per cent of the overall manufacturing costs. Discussed is the development of a low‐cost PC‐based computer assisted tool, used to analyse the component geometric features from an engineering drawing for automatic assembly. A description of the algorithms used to evaluate the overall geometric dimensions, its alpha and beta symmetries from a DXF file will also be made. Goes on to compare the results between the simulated runs and the actual ones of various complex 2‐D and 21/2‐D components and this has been found to be satisfactory. Quicker estimates of the component handling times for assembly can therefore be achieved.
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Milan Tung‐Wen Sun, Mei‐Chiang Shih, Keng‐Ming Hsu and Jenhei Chen
The purpose of this paper is twofold: to analyse the diffusion of an innovative policy or service and the factors influencing it through an explorative study of the diffusion of…
Abstract
Purpose
The purpose of this paper is twofold: to analyse the diffusion of an innovative policy or service and the factors influencing it through an explorative study of the diffusion of the Bookstart program in Taiwan; and second, to provide an analytical framework for further study of this program.
Design/methodology/approach
The study is both empirical and theoretical. It uses data from existing studies and also agencies involved in Bookstart to explain the diffusion of the program. It then draws on theories of policy diffusion and the initial findings of this study to develop an analytical framework for the further study of the diffusion of the Bookstart program.
Findings
The Bookstart program, which is designed to promote reading habits for children 0 to 3 years old and to strengthen parent‐children relations, was originally initiated in the UK. It was first introduced into Taiwan in Taichung County in 2003. The paper shows how the program spread throughout Taiwan and indicates the role of the key players in the diffusion, including charitable institutions, local politicians and leaders, local authority agencies, and the Ministry of Education. The paper posits an analytical framework identifying factors which may help to promote or facilitate the diffusion. In this respect, the paper draws on the theoretical literature and also initial evidence from the research so far undertaken. This will guide the research in the next stage of the study.
Originality/value
This explorative study provides an example of the nature, process and direction of the diffusion of a policy or service innovation, and suggests the possible factors promoting or facilitating it, as identified in the initial findings of the research and in the relevant theoretical literature.
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He‐Chun Wang, Jing‐Qin Su, Hui‐Ling Cao and Sai‐Nan Sun
In China the maturity of the industrial development has the demonstration and reference implications for how to achieve enterprises competitiveness among the developing industries…
Abstract
Purpose
In China the maturity of the industrial development has the demonstration and reference implications for how to achieve enterprises competitiveness among the developing industries in a country. With the development of globalization, how to improve the enterprises competitiveness has became a serious problem to be solved for Chinese enterprises. The management innovation is reasonable and appropriate to solve this problem. Compared with the independent innovation, adoptive management innovation has become the main way for enterprises to fulfill the management innovation and change the management styles under the open economy condition. The research strives to reveal the “black box” in the management innovation adoptive process and give an answer to a series of questions, such as “what is the role of entrepreneurs in management innovation adoptive process?”
Design/methodology/approach
Exploratory case study approach is taken to find the entrepreneurs' role in management innovation adoptive process of Chinese traditional industry.
Findings
This paper constructs the adoptive management innovation model from three dimensions, using exploratory case technique, which explores the key factors and mechanism of realizing management innovation adoption. Through the exploratory case analysis to verify the viewpoint which is proposed by the model: entrepreneurs played a leading role in the adoptive management innovation of non‐procedural process, and the role is the result of the mixed function of the external and internal environment. Entrepreneurs analyze and explore the new problems and opportunities, and their own experience and ability determine the cognition and explore degree towards these problems directly; entrepreneurs' integration ability of resources can be approved and accepted after the new practice has been proposed and become mature. Entrepreneur long‐term shaping on organizational resources determines whether the management innovations introduction would be really integrated into enterprise management system. The entrepreneur's typical behavior on “integration, learning and shaping” is the foundation and guarantee of adoptive management innovation, which have connective effect on adjacent stages.
Originality/value
The article describes Haier BPR process of adoptive management innovation and the adoptive management innovation mode, and analyzes the effect of entrepreneurs' role on adoptive management innovation of China's color TV industry. The Chinese color TV industry as the maturity industry has the demonstration and reference implications for how to achieve enterprises competitiveness in Chinese developing industries.
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Abstract
The interbank market in China experienced remarkable squeezes in liquidity in 2013. In particular, the overnight Shanghai Interbank Offered Rate reached a historical high in June. Banks were unprepared, facing the occurrence of various liquidity demands simultaneously. Effects of the liquidity squeeze spread across markets, and concerns were expressed about the health of the banking sector in the world’s second largest economy. Yet the central bank of China maintained an unswerving view that the tightness of liquidity was only structural, and could be overcome by the commercial banks themselves. While it may be too early to judge whether the central bank was correct, or whether there is systematic liquidity risk in the banking sector, markets received a clear signal from the People’s Bank of China. The central bank stopped acting as a ‘perpetual put option’ for commercial banks and refused to take responsibility to satisfy liquidity needs in the interbank market. Its intention is clear; that is, to adjust monetary policy and support economic reform in China. The new Chinese government seems determined to steer a new course away from the previous growth episode. Its resolution has been published and actions have been taken. Among them, the central bank’s changes to monetary policy have received responses from the markets, and the People’s Bank of China is now in the vanguard of a battle to squeeze liquidity. It is difficult to predict what further actions the government will take. However, it should be aware that the driving force of economic reform in China comes from structural change and productivity improvement. Without follow-up policies, complication in the financial system could undermine the central bank’s effort and international capital flows may quickly substitute the opening position of the central bank in the interbank market. More wisdom is required if China is to win the battle for deleveraging and structural reform.