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The purpose of this paper is to analyze the cavitation characteristics of a water hydraulic axial piston motor (WHAPM) to improve the water motor performance, to reduce the vibration and noise and to prolong the service life of the motor.

The computational fluid dynamics (CFD) software PumpLinx is chosen to do cavitation analysis of the WHAPM. In this case, first, cavitation mechanism of the water piston motor is analyzed in depth. Then, considering the effects of bubble dynamics, the rate of phase transition, turbulence effects and non-condensable gas, the full cavitation model is selected, the dynamic CFD numerical model of internal flow field on the water hydraulic piston motor is established based on PumpLinx software and the fluid cavitation inside is numerically studied. Finally, the influence of the valve plate and pistons on motor cavitation is analyzed.

Research results show that there are two serious cavitation regions: one is the pressure transition region of the valve plate that is near the top dead center, and the other is the low-pressure region of the piston that is near the low-pressure transition area. Moreover, the more serious cavitation area is on the valve plate region.

The simulation results show that the proposed algorithm is able to detect the cavitation characteristics of the water piston motor. Besides, it is deduced that valve-plate structure optimization is more important than pistons to reduce cavitation influence.

Honey peaches are rich in a variety of vitamins and are well known in China as the queen of fruit. However, as highly climacteric fruit, peach is too easy to affect its economic value. In this paper, a new passive modified atmosphere packaging system was proposed to solve the lack of water vapour removal capacity – which is still the technical bottleneck of passive modified atmosphere packaging. This paper aims to address this issue.

Under the conditions of relative humidity 85−90% and temperature 28°C−38°C, the influence of new passive modified atmosphere packaging on the shelf life and quality of 70% ripe peaches was studied in the paper. The effect of the new passive modified atmosphere packaging (PMAP) on fruit appearance, colour, taste, flavour, soluble solids, Vitamin C and titratable acid was investigated.

Regardless of whether 1-Methylcyclopropene is added or not, the research results show that the new PMAP has a significant effect on extending the shelf life and maintaining the quality of peaches. Compared with the control group, the shelf life of peaches treated with modified atmosphere packaging and 1-Methylcyclopropene was prolonged by 7 and 11 days, increasing the retailer's revenue by 44 and 75%.

A new integrated structure, which is composed of two types of films with high oxygen and high water vapour permeability was designed for the retail of peaches at room temperature. The former was mainly responsible for regulating the concentration of O₂ and CO₂, while the latter was for removing water vapour and regulating the relative humidity in PMAP.

This paper aims to optimize the weighing control system and compensate weighing error for weighing control system of coal mine paste-filling weighing control system.

The process of the paste-filling weighing control system is analyzed and the mathematical model of the paste-filling material weight is established. Then, the back-propagation (BP) neural network is used to optimize the control system and compensate the weighing error.

Without the BP neural network, the weighing error of the paste-filling control system is more than 3 per cent, whereas after optimization with the BP neural network, the weighing error is less than 1 per cent. With the simulation results, it is seen that the weighing error of the paste-filling control system decreases and the accuracy of the weighing control system improves and optimizes.

The method can be further used to improve the control precision of the coal mine paste-filling system.

This paper aims to study a modular method for designing a paste filling station (PFS) for a coal mine (CM) to reduce the PFS’s input cost and achieve reutilization.

Modular design criteria for the PFS are proposed and a modular division (MDiv) model and an evaluation method are established. The correlation-strength matrix of the PFS parts expressed in the form of rough numbers is transformed into a fuzzy equivalent matrix. The theory of rough sets and the fuzzy clustering method are introduced for PFS MDiv. The evaluating method is established for the PFS MDiv scheme based on the principle of fuzzy comprehensive evaluation.

Taking a particular CM PFS as an example, the above method is used to modularize the PFS, and the optimal division of the PFS is finally determined via the above evaluation system. Applying this method solves the problem of high cost investment in the initial stage of PFS construction.

The theory of rough sets and the fuzzy clustering method are introduced for PFS MDiv. An evaluating method is established for the PFS MDiv scheme based on the principle of fuzzy comprehensive evaluation, thereby providing new ideas for PFS transformation and reutilization.

The purpose of this study is to analyze the speed characteristics of the water hydraulic axial piston motor. The speed performance of water hydraulic piston motor which uses water as medium is different from that mineral oil one.

To analyze the speed characteristics of the water hydraulic motor, the speed model of a swash plate water hydraulic piston motor is developed theoretically and a simulation model with AMESim is built.

The effects of clearance between friction pairs and input pressure on the speed are analyzed and compared between the theoretical and numerical models.

The results of the theoretical and simulation models both verify that the clearance of friction pairs is the key factor in the hydraulic piston motor’s speed.

The purpose of this paper is to examine empirically how managers establish ethical guanxi (interpersonal relationships) with their business partners to prevent potential ethical incidences in Chinese and Western business contexts.

The present study is guided by a qualitative, abductive approach and draws on in-depth interviews with ten senior managers in five urban New Zealand organisations.

The results point out that guanxi (interpersonal relationships) purely working through renqing (reciprocity) is not sustainable, because it perpetuates a never-ending cycle of favours, once exchanging favours stopped or disappeared, then business relationships dwindled. To establish an ethical guanxi model, the authors found that xinyong (trust) is the foundation, and its enlargement stimulates lijie (empathy) that transfers pure business relationships to a genuine friendship which enhances ethical decision-making. They also posit that once managers are embodied with lijie, then they will have the virtue of ren to behave like junzi (ideal Confucian ethical person) whose business actions tend to be intrinsically guided by a sense of obligation to do something right that will work for diverse stakeholders’ interests, for the prosperity of organisations and society.

This study suggests that managers should take Confucian virtues of xinyong (trust) and lijie (empathy), because they will trigger ren (humanity) as an intrinsic value. In this way, it is more likely for them to become junzi (ideal Confucian ethical person) whose business actions are intrinsically guided by a sense of obligation to do something right that benefits various stakeholders, organisations and society.

This study contributes to the extant literature on preventing ethical incidents of guanxi (interpersonal relationships) by drawing a framework of ethical guanxi, which is built on Confucian virtues of xinyong (trust), lijie (empathy) and ren (humanity). Further, this paper strongly suggests that companies should educate their staff to become more humane to make moral decisions in daily management practice.

The purpose of this paper is to study a new liquid-phase assisted texture treatment method to improve the tribological properties of 304 stainless steel.

Three groups of textured type (KY, KJ and YJ) were prepared on 304 stainless steel surface using laser circular and cross scanning method in air and liquid assisted condition. The surface morphology and element content of test samples were measured with scanning electron microscope, energy spectrum. Then, the tribological test was carried out using MWF-500 reciprocating friction and wear testing machine under dry and oil lubrication condition.

The experimental results showed that the textured surface of laser processing in air was obviously blackened, and the oxygen content was increased from 16.9% to 24%. These cases did not occur on liquid-assisted laser textured surface, which induced a better wettability and surface texture processing quality. For friction test, the friction coefficient of cross-scanning textured surface prepared in assisted liquid (YJ) was the smallest. It is reduced by 55% in oil lubrication case compared to the original surface (YS). The cross-scanning textured surface prepared in air (KJ) was a little worse in friction coefficient and a little better in wear quantity than the cross-scanning textured surface prepared in assisted liquid (YJ). It is indicated that the laser processing surface with assisted liquid has obvious advantages in surface texture quality and interfacial tribological property. The main reason is that the assisted liquid plays a role in cooling and protecting action of the machined surface. The bubbles, generated at the solid–liquid interface because of the laser heat effect, scatter the laser beam and carry out the processed melt meanwhile. The lubricating medium is easier to penetrate and store in the contact interfaces because of the higher surface textured performance and wettability.

The main contribution of this work is in providing a new surface texture processing method that has a better surface micropits quality and interfacial tribology regulation ability.

The purpose of this study is to develop the existence and mechanism of stress corrosion cracking (SCC) for A517 steel in marine environments.

Slow strain rate test (SSRT) and constant load tests were used to investigate the SCC susceptibility of A517 steel. In addition, the additive stresses caused by the corrosion film and hydrogen entering into steel were applied to reveal the fundamental mechanism of the SCC.

The SCC susceptibility increased due to anodic dissolution and additive stress caused by the corrosion-produced film under anode polarization. Furthermore, the SCC susceptibility increased with increasing cathodic polarization, which is due to the increased additional stress caused by hydrogen entering into the steel. However, when the cathode polarization further increased, the additional stress remained due to the constant hydrogen content, thus the SCC susceptibility did not vary. Moreover, the SCC susceptibility of A517 steel under an alternate immersion environment (AIE) was lower than that under a full immersion environment and the steel under the AIE with 0.5 W/D had the lowest SCC susceptibility.

The stress corrosion behaviors of A517 in marine environments under various conditions were systematically analyzed.

This study aims to report the CO₂ corrosion performance of 3Cr steel and 3Cr2Al steel and reveal the role of aluminum in mitigating corrosion of low-Cr steel.

Aluminum was added to 3Cr steel to prepare a new type of 3Cr2Al steel, and the effect of aluminum on the corrosion resistance of pipeline steel was studied using morphology observation and composition analysis, weight loss tests and electrochemical test.

In the CO₂/O₂ coexistence environment, the average corrosion rate of the 3Cr2Al steel was obviously lower than that of the 3Cr steel. The addition of aluminum expanded the range of prepassivation, and the dynamic potential polarization curve of 3Cr2Al steel showed duplex prepassivation phenomena. 3Cr steel underwent severe local corrosion, and 3Cr2Al steel underwent uniform corrosion. The addition of aluminum contributed to the formation of a dense corrosion product layer and greatly reduced the localized corrosion sensitivity.

The studies on CO₂ corrosion of aluminum containing low-Cr steel are quite rare. This study clarifies the role of aluminum by comparing the corrosion behavior of 3Cr2Al and 3Cr steel. The effect of aluminum on the growth of corrosion product film was discussed, and the duplex prepassivation phenomena of Cr and Al were revealed.

This study seeks to fill a gap in the literature by examining the role of family firm succession in shaping the firm's approach to financialisation, which has received limited attention in the previous research. In addition, the study explores the influence of factors such as clan culture, concentration of control and generational differences on the relationship between succession and financialisation.

Data were based on a sample of 7,023 firm-year observations, compiled from the listed family firms in China's A-share. Several tobit models are used for analysing the data and testing the hypotheses.

Family firm succession is negatively related to the level of financialisation, and this relationship is influenced by clan culture, concentration of control and the stage of succession. Specifically, a higher clan culture, a greater concentration of ultimate control by the controlling family member and the dominance of the first generation in management strengthens the negative relationship between family firm succession and financialisation.

This study offers new insights into the consequence of family firm succession on a new area of the firm's strategy, i.e. financialisation. The study further advances the understanding of family firm succession by considering the role of clan culture, the concentration of control and the stage of the succession process.