Green manufacturing is increasingly becoming popular, especially in lubricant manufacturing, as more environmentally friendly substitutes for mineral base oil and synthetic additives are being found among plant extracts and progress in methodologies for extraction and synthesis is being made. It has been observed that some of the important performance characteristics need enhancement, of which nanoparticle addition has been noted as one of the effective solutions. However, the concentration of the addictive that would optimised the performance characteristics of interest remains a contending area of research. The research was out to find how the concentration of green synthesized aluminum oxide nanoparticles in nano lubricants formed from selected vegetable oils influences friction and wear. A bottom-up green synthesis approach was adopted to synthesize aluminum oxide (Al2O3) from aluminum nitrate (Al(NO3)3) precursor in the presence of a plant-based reducing agent—Ipomoea pes-caprae. The synthesized Al2O3 nanoparticles were characterized using TEM and XRD and found to be mostly of spherical shape of sizes 44.73 nm. Al2O3 nanoparticles at different concentrations—0.1 wt%, 0.3 wt%, 0.5 wt%, 0.7 wt%, and 1.0 wt%—were used as additives to castor, jatropha, and palm kernel oils to formulate nano lubricants and tested alternately on a ball-on-aluminum (SAE 332) and low-carbon steel Disc Tribometer. All the vegetable-based oil nano lubricants showed a significant decrease in the coefficient of friction (CoF) and wear rate with Ball-on-(aluminum SAE 332) disc tribometer up to 0.5wt% of the nanoparticle: the best performances (eCOF = 92.29; eWR = 79.53) came from Al2O3-castor oil nano lubricant and Al2O3-palm kernel oil; afterwards, they started to increase. However, the performance indices displayed irregular behaviour for both COF and Wear Rate (WR) when tested on a ball-on-low-carbon steel Disc Tribometer.
The growing of plants hydroponically is a soilless form of growing in modern day agriculture. It helps to make feed available for animals throughout the season since it is not affected by what is faced by field grown crops. The use of animal waste, that is, their faeces, in the growth of forage was compared with commercial hydroponics solutions as a way of looking for a reduction in the cost incurred in the purchase of commercial hydroponics solutions. The study evaluated the use of organic nutrient solutions (ONS) alongside a standard/commercial nutrient solution in growing crops hydroponically on the growth, dry matter yield, water use efficiency, and chemical composition of hydroponic maize fodder. The ONS used were formulated from the dried faeces of cattle, poultry, rabbits, and swine. The prepared organic nutrient solutions with the control were used in growing the maize seeds for 10 days, and growth, yield, and chemical composition were determined. Results show the highest (196 g) dry matter yield for maize hydroponic fodder irrigated with poultry ONS. Similarly, maize irrigated with poultry ONS was significantly (P < 0.05) higher in CP content, while it was not significantly different from maize irrigated with cattle, swine, and commercial solutions. A lower water use efficiency value (0.19 kg DM/m3) was recorded for maize irrigated with cattle ONS. According to the study, irrigating maize with different organic nutrient solutions produced maize fodder with a higher yield and a similar chemical composition as the commercial nutrient solution.
This research delves into the intricate dynamics of ethical leadership within the context of Vietnamese Small and Medium Enterprises (SMEs). By scrutinizing its impact on organizational effectiveness, the study unveils a comprehensive understanding of the interconnectedness between ethical leadership, knowledge sharing, and organizational learning. Employing a mixed-methods approach, the research investigates the mediating roles played by knowledge sharing and organizational learning in the relationship between ethical leadership and organizational effectiveness. Through empirical analysis and case studies, this study contributes valuable insights to the literature, offering practical implications for fostering ethical leadership practices in Vietnamese SMEs to enhance overall organizational effectiveness. The findings shed light on the nuanced mechanisms through which ethical leadership contributes to sustainable success, emphasizing the pivotal roles of knowledge sharing and organizational learning in this intricate relationship.
On the basis of the framework of Perceptual Assimilation Model connected to speech perception, this paper reports on a study of the relationship between the experience of L1 (Chinese) and L2 (English) production from the point of lexical stress level. Chinese EFL speakers were recruited for this study. All the participants were required to read 20 words in the form of English, of which the lexical stress was recorded so as to make further analysis and comparison. The study indicates that the biggest challenge for Chinese EFL learners is the misplacement of word stress. It often occurs in polysyllabic words, and there is a strong tendency of stress shift on the second syllable. The dominant reason for the misplacement is that the second or the latter syllable is frequently stressed in mandarin dissyllables. This implies that Chinese EFL learners should lay more emphasis on phonological awareness of L2 and sufficient supply of L2 auditory input should also be assured in order to maintain the quality of perception and production in stress acquisition.
Despite being controversial, teacher tenure policies are understudied, particularly in higher education contexts outside the Western world. Using semi-structured interviews with 15 university faculty members, this study explored how tenure systems influence the teaching practices, motivations, and job satisfaction of language teachers in Macau's universities. It was revealed that Macau implemented competitive, “up or out” tenure policies that were based on research output. Faculty were anxious as vague expectations heightened research priorities over teaching quality and student support. Requirements also strained collegial relationships as faculty goals focused on promotion. Veteran professors demonstrated resilience, maintaining intrinsic motivation despite policies. They advocated improving policies by promoting transparency, balancing workloads, accommodating disciplines, and communicating effectively. Using empirical data, this study identifies key policy implications for supporting teacher motivation while balancing inequality constraints. It provides empirical insight into optimizing tenure for teacher engagement and fulfillment.
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