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1 – 10 of 15Huaxia Yang, Jinlong Cheng, Allen D. Schaefer and Shion Kojo
The authors examined the influence of perceived value on consumer attitude and purchase intention (PI) and the relationship between attitude and PI towards sustainable luxury…
Abstract
Purpose
The authors examined the influence of perceived value on consumer attitude and purchase intention (PI) and the relationship between attitude and PI towards sustainable luxury products (SLP) in China.
Design/methodology/approach
An online survey was conducted with 935 consumers of luxury fashion in mainland China. Structural equation modelling was applied to measure and analyse the relationship between values (i.e. hedonic values, social values, and value for money) and consumer attitude and PI.
Findings
Consumers' multidimensional values positively affected their attitude. Social values and value for money had a significant positive effect on PI towards SLP. However, hedonic values had no effect on PI.
Research limitations/implications
The sample was drawn from first-tier cities in China, and the results cannot be generalised. The authors examined three dimensions of consumption values. Future research should consider additional markets, values, and influencing factors.
Practical implications
Luxury companies should understand Chinese consumers' diverse values and develop sustainable products that meet consumers' principles. These principles increase the perceived value of the products and thereby guide luxury brands to make marketing strategies to increase sales.
Originality/value
This is the first empirical study to use the theory of perceived value scale (PERVAL) to understand consumer behaviour regarding SLP in China.
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Keywords
Fupeng Cheng, Jinglong Cui, Shuai Xu, Song Li, Pengchao Zhang and Juncai Sun
The purpose of this study is to improve the performance of AISI 430 stainless steel (430 SS) in increasing its oxidation resistance, suppressing coating spalling and cracking…
Abstract
Purpose
The purpose of this study is to improve the performance of AISI 430 stainless steel (430 SS) in increasing its oxidation resistance, suppressing coating spalling and cracking, sustaining appropriate conductivity and blocking Cr evaporation as an interconnect material for intermediate temperature solid oxide fuel cells; a protective co-contained coating is formed onto stainless steel via the surface alloying process and followed by thermal oxidation.
Design/methodology/approach
In this work, oxidation behavior of coated specimen is studied during isothermal and cyclic oxidation measurements. Moreover, the conductivity is also investigated by area specific resistance (ASR) measurement.
Findings
Co-contained spinel layer shows an outstanding performance in preventing oxidation and improving conductivity compared with uncoated specimens. The protective spinel coating also reduces the ASR for coated specimen (0.0576O cm2) as compared to the uncoated specimen (1.87296O cm2) after isothermal oxidation.
Originality/value
The probable mechanism of co-contained alloy converting into spinel and the spinel transfer electron is presented.
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Rui Zhang, Lei Zhao, Dan Xie, Jinlong Song, Wendong Zhang, Lihu Pan and Yanhua Zhang
This study aims to simulate and test the performance of a transmitting and receiving capacitive micro-machined ultrasonic transducer (CMUT). Aimed at detecting demand of the CMUT…
Abstract
Purpose
This study aims to simulate and test the performance of a transmitting and receiving capacitive micro-machined ultrasonic transducer (CMUT). Aimed at detecting demand of the CMUT, a matched integrated adjustment circuit was designed through analyzing processing methods of transducer’s weak echo signal.
Design/methodology/approach
Based on the analysis of CMUT array structure and work principle, the CMUT units are designed and the dynamic performance analysis of SIMULINK is given according to the demand of underwater detecting. A transceiver isolation circuit is used to make transmission mode and receiving mode separate. A detection circuit is designed based on the transimpedance amplifier to achieve extraction of high-frequency and weak signal.
Findings
Through experimentation, the effectiveness of the CMUT performance simulation and the transceiver integrated adjustment circuit were verified. In addition, the test showed that CMUT with 400 kHz frequency has wider bandwidth and better dynamic characteristics than other similar transducers.
Originality/value
This paper provides a theoretical basis and design reference for the development and application of CMUT technology.
Details
Keywords
- MEMS
- Dynamic performance
- Ultrasonic sensors
- Underwater applications
- Detection circuit
- Transmission transducer
- Capacitive micro-machined ultrasonic transducer
- Receipt and transmission transducer
- MEMS
- Dynamic performance
- Ultrasonic sensors
- Underwater applications
- Detection circuit
- Transmission transducer
- Capacitive micro-machined ultrasonic transducer
Fupeng Cheng, Jinglong Cui, Shuai Xu, Hongyu Wang, Pengchao Zhang and Juncai Sun
The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton exchange…
Abstract
Purpose
The purpose of this paper is to improve the surface electrical conductivity and corrosion resistance of AISI 430 stainless steel (430 SS) as bipolar plates for proton exchange membrane fuel cells (PEMFCs), a protective Nb-modified layer is formed onto stainless steel via the plasma surface diffusion alloying method. The effect of diffusion alloying time on electrochemical behavior and surface conductivity is evaluated.
Design/methodology/approach
In this work, the surface electrical conductivity and corrosion resistance of modified specimen are evaluated by the potentiodynamic and potentionstatic polarization tests. Moreover, the hydrophobicity is also investigated by contact angle measurement.
Findings
The Nb-modified 430 SS treated by 1.5 h (1.5Nb) presented a lower passivation current density, lower interfacial contact resistance and a higher hydrophobicity than other modified specimens. Moreover, the 1.5 Nb specimen presents a smoother surface than other modified specimens after potentionstatic polarization tests.
Originality/value
The effect of diffusion alloying time on electrochemical behavior, surface conductivity and hydrophobicity of modified specimen is evaluated. The probable anti-corrosion mechanism of Nb-modified specimen in simulated acid PEMFC cathode environment is presented.
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Keywords
Ying Lv, Jinlong Feng, Guangbin Wang and Hua Li
This study aims to improve the maneuverability and stability of four-wheel chassis in a small paddy field; a front axle swing steering four-wheel chassis with optimal steering is…
Abstract
Purpose
This study aims to improve the maneuverability and stability of four-wheel chassis in a small paddy field; a front axle swing steering four-wheel chassis with optimal steering is designed.
Design/methodology/approach
When turning, the front inner wheel stops and the rear inner wheel is in the following state. The hydraulic drive system of the walking wheel adopts a driving mode in which two front-wheel motors are connected in series and two rear wheel motors in parallel. The chassis uses a combination of a gasoline engine with a water cooling system, a CVT continuously variable transmission and a hydraulic drive system to increase the control capability. The front axle rotary chassis adopts a step-less variable speed engine and a hydraulic control system to solve the hydraulic stability of the chassis in uphill and downhill conditions so as to effectively control the over-speed of the wheel-side drive motors. Through the quadratic orthogonal rotation combination design test, the mathematical models of uphill and downhill front-wheel pressures and test factors are established.
Findings
The results show that the chassis stability is optimal when the back pressure is 0.5 MPa, and the rotating slope is 4°. The uphill and downhill pressures of the front wheels are 2.38 MPa and 1.5 MPa, respectively.
Originality/value
The influence of external changes on the pressure of hydraulic motors is studied through experiments, which lays the foundation for further research.
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Keywords
Jixin Han, Haibang Zhang, Juncai Sun, Wenyuan Zhao and Jinlong Cui
The purpose of this study is to improve the surface electrical conductivity and corrosion resistance of AISI430 stainless steel (430 SS) as bipolar plates for direct formic acid…
Abstract
Purpose
The purpose of this study is to improve the surface electrical conductivity and corrosion resistance of AISI430 stainless steel (430 SS) as bipolar plates for direct formic acid fuel cell (DFAFC).
Design/methodology/approach
The niobium diffusion layers have been successfully synthesized on 430 SS substrate by the plasma surface diffusion alloying technique under different diffusion alloying time.
Findings
The surface morphology of Nb-modified 430 SS prepared under the diffusion alloying time of 2 h is more homogeneous, relatively sleek and compact without surface micropore and other common surface blemishes. The potentiostatic and potentiodynamic polarization measurements manifest that Nb-modified 430 SS prepared under the diffusion alloying time of 2 h enormously ameliorate the corrosion resistance of bare 430 SS compared with other Nb-modified 430 SS samples and its corrosion current density is maintained at −1.4 µA cm−2 in simulated anodic environment of DFAFC (0.05 M H2SO4 + 2 ppm HF + 10 M formic acid at 50 °C).
Originality/value
The effect of diffusion alloying time on the corrosion resistance and surface conductivity of Nb-modified 430 SS has been carefully studied. The Nb-modified 430 SS samples prepared at the diffusion alloying time of 2 h have the best surface electrical conductivity and corrosion resistance in the simulated anodic environment of DFAFC.
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Keywords
Zhifeng Liu, Junyuan Guo, Yumo Wang, Dong Xiangmin, Yue Wu, Zhijie Yan and Gong Jinlong
This paper aims to propose a method for finding the maximum rotational speed of an inclined turntable at which the stability of the bearing oil film is maintained.
Abstract
Purpose
This paper aims to propose a method for finding the maximum rotational speed of an inclined turntable at which the stability of the bearing oil film is maintained.
Design/methodology/approach
The finite difference method was used to solve the Reynolds equation. Variation of bearing capacity of a tilted hydrostatic turret over time was determined. The combined effect of tilt and rotational speed of the turret on the oil film stability was also analyzed.
Findings
When the turntable is operated at low speeds with only small angle of tilt, stability of the oil film is maintained. At lower rotational speeds, a smaller angle of tilt improves the bearing capacity and ensures stability of the oil film. Whereas, higher rotational speeds can have a considerable influence on the bearing capacity.
Originality/value
The results demonstrate that the inclination or tilt of the turntable significantly affects the stability of the oil film.
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Keywords
Wenchao Xi, Boxue Song, Jinlong Dong, Tianqi Zhang, Tianbiao Yu and Jun Wang
Laser cladding has been used in the field of repairing damaged parts of machine tools due to its advantages of less processing restrictions and easy formation of a good…
Abstract
Purpose
Laser cladding has been used in the field of repairing damaged parts of machine tools due to its advantages of less processing restrictions and easy formation of a good metallurgical bond with the base material. However, the mechanical properties of the coating sometimes cannot meet the process requirements. Therefore, the purpose of this paper is to prepare coatings with high microhardness and flexural strength.
Design/methodology/approach
The YCF102 alloy powder was mixed with different contents of Co and tested for laser cladding on AISI 1045 substrate under the same process parameters. The main phase composition of the coating was revealed by the XRD results. The main chemical composition of the coating was determined by the SEM and EDS results. In addition, the effect of Co content on the microstructure, microhardness and flexural strength of the coatings was investigated.
Findings
The results show that when the Co content is 2 wt% and 4 wt%, Co does not form compounds with other elements, but is uniformly distributed in the coating. And when the Co content is 6 wt% and 8 wt%, the Co reacts with Fe in the coating and generates Co3Fe7 in situ. The increase in Co did not result in a monotonic change in microhardness, but significantly improved the flexural strength and the flatness of the microstructure of the coating. When the Co content of the mixed powder is 8 wt%, the coating has high microhardness and flexural strength.
Originality/value
Co/YCF102 composite coating with high microhardness and flexural strength was prepared. This paper provides a theoretical and practical basis for research in the area of repairing damaged parts of machine tools by laser cladding.
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Keywords
Rui Zhang, Wendong Zhang, Changde He, Jinlong Song, Linfeng Mu, Juan Cui, Yongmei Zhang and Chenyang Xue
The purpose of this paper was to develop a novel capacitive micromachined ultrasonic transducer (CMUT) reception and transmission linear array for underwater imaging at 400 kHz…
Abstract
Purpose
The purpose of this paper was to develop a novel capacitive micromachined ultrasonic transducer (CMUT) reception and transmission linear array for underwater imaging at 400 kHz. Compared with traditional CMUTs, the developed transducer array offers higher electromechanical coupling coefficient and higher directivity performance.
Design/methodology/approach
The configuration of the newly developed CMUT reception and transmission array was determined by the authors’ previous research into new element structures with patterned top electrodes and into directivity simulation analysis. Using the Si-Silicon on insulator (Si-SOI) bonding technique and the principle of acoustic impedance matching, the CMUT array was fabricated and packaged. In addition, underwater imaging system design and testing based on the packaged CMUT 1 × 16 array were completed.
Findings
The simulation results showed that the optimized CMUT array configuration was selected. Furthermore, the designed configuration of the CMUT 1 × 16 linear array was good enough to guarantee high angular resolution. The underwater experiments were conducted to demonstrate that this CMUT array can be of great benefit in imaging applications.
Practical implications
Based on our research, the CMUT linear array has good directivity and good impedance matching with water and can be used for obstacle avoidance, distance measurement and imaging underwater.
Originality/value
This research provides a basis for CMUT directivity theory and array design. CMUT array presented in this paper has good directivity and has been applied in the underwater imaging, resulting in a huge market potential in underwater detection systems.
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Zhen Li, Yufan Lu, Chi Zhang, Jinlong Dong, Xiaoli Zhao and Liqin Wang
The traction behaviours of lubricating oil significantly affect the stability and lubrication regime of aviation high-speed ball bearings. Rolling elements will slide at a low…
Abstract
Purpose
The traction behaviours of lubricating oil significantly affect the stability and lubrication regime of aviation high-speed ball bearings. Rolling elements will slide at a low traction force (TF). Therefore, traction behaviours need to be studied, and a fitting expression for traction curves to rapidly calculate the traction coefficient (TC) should be developed.
Design/methodology/approach
The traction behaviours of an aviation lubricating oil were studied in severe operating conditions with a self-designed two-disc testing rig. Based on the least squares method and the Levenberg–Marquardt theory, a rapid calculation expression was developed by fitting the obtained traction curves. The correction of this expression was experimentally verified by comparing the TCs under different operating conditions. This expression was also used to modify the commonly accepted quasi-dynamic model of rolling bearings.
Findings
An increase of the load led to an increase in the TC. In comparison, the temperature and entrainment speed showed inverse effects. The proposed expression exactly predicted the trend of the experimentally acquired traction curve. The calculation with the modified dynamic model showed that the action of the TF on a single rolling element varied and that the temperature increase of the outer raceway is higher than the inner raceway, which is caused by the TF and relative sliding speed between the elements and raceways.
Originality/value
The proposed fitting expression is able to simplify the TC calculation of synthetic aviation lubricating oil in practical engineering applications. This paper can provide an important reference for the traction behaviour of synthetic aviation lubricating oil under severe conditions and assist with its rapid calculation and practical application in engineering.
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