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The development of renewable sources for energy production has assumed a vital role in recent years, particularly with regard to the preservation of energy supplies and the environment. In this regard, municipal green waste (MGW) can be a potential renewable energy source if it is integrated with emerging technology, like pyrolysis. Therefore, this study aimed at investigating the effect of residence time and particle size on the yield and composition of oil derived from MGW using fast pyrolysis in an auger reactor. The residence time and particle size were varied from 1 min to 4 min and 1 mm to 10 mm, respectively, while keeping the temperature constant at 500 °C. At a residence time of 3 min, a 2 mm particle size provided the highest bio-oil yield (39.86%). At this experimental setting, biochar yield of 27.16% and syngas yield of 32.98% were obtained. The characterization of produced bio-oil revealed that a total of nine functional groups were present in the bio-oil. The phenols were highest in amount, followed by aromatics and ketones. The increase in residence time decreased the amount of acidic compounds present in the bio-oil. The water content was decreased by ~11% and the calorific value was increased by ~6% with the increase in particle size from 1 mm to 10 mm. Other properties, such as viscosity, density, cetane number, and flash point, did not change significantly with the change in experimental conditions. With a calorific value of 25+ MJ/kg, although the bio-oil produced from MGW can be used for heating (such as in boilers and furnaces), the use of MGW bio-oil in engines requires appropriate upgrading through procedures like hydrodeoxygenation, catalytic cracking, esterification, etc. [ABSTRACT FROM AUTHOR]

Engineering education providers should foresee the potential of digital transformation of teaching and skill-developing activities so that graduating engineers can find themselves highly aligned with the demands and attributes needed by prospective industrial employers. The advancement of industrial revolutions towards hybridisation of the enabling technologies recognised by Industry 4.0, Society 5.0, and Industry 5.0 have transformed the components of the engineering higher education system remarkably. Future workforce requirements will demand an employee's multidisciplinary skill mix and other professional qualities. Implementing human-centric decision-making based on insights from the Digital Twin (DT) systems, sustainability, and lean systems is necessary for further economic growth. Recent barriers identified by the Australian Council of Engineering Deans, the development of teaching capabilities, and affordable and digitally transformed learning facilities by education providers were all considered. This paper explores the role of Digital Twins (DTs) in enhancing engineering higher education by incorporating Industry 4.0 components and other industrial advances. By reviewing curricula, pedagogy, and the evolving skill requirements for engineering graduates, this study identifies key benefits of DTs, such as cost-effectiveness, resource management, and immersive learning experiences. This paper also outlines challenges in implementing DT-based labs, including IT infrastructure, data quality, privacy, and security issues. The findings indicate that engineering education should embrace DTs to foster multidisciplinary skills and human-centric decision-making to meet future workforce demands. Collaboration with industry is highlighted as a crucial factor in the successful transformation of teaching practices and in offering real-world experiences. The COVID-19 pandemic has expedited the adoption of DT technologies, demonstrating their utility in minimising educational disruptions. While this paper acknowledges the high potential of DTs to prepare engineering students for future industry demands, it also emphasises the need for professional development among educators to ensure effective and balanced implementation. [ABSTRACT FROM AUTHOR]

This study investigated the suitability of stone fruit seed as a source of biodiesel for transport. Stone fruit oil (SFO) was extracted from the seed and converted into biodiesel. The biodiesel yield of 95.75% was produced using the alkaline catalysed transesterification process with a methanol-to-oil molar ratio of 6:1, KOH catalyst concentration of 0.5 wt% (weight %), and a reaction temperature of 55 °C for 60 min. The physicochemical properties of the produced biodiesel were determined and found to be the closest match of standard diesel. The engine performance, emissions and combustion behaviour of a four-cylinder diesel engine fuelled with SFO biodiesel blends of 5%, 10% and 20% with diesel, v/v basis, were tested. The testing was performed at 100% engine load with speed ranging from 200 to 2400 rpm. The average brake specific fuel consumption and brake thermal efficiency of SFO blends were found to be 4.7% to 15.4% higher and 3.9% to 11.4% lower than those of diesel, respectively. The results also revealed that SFO biodiesel blends have marginally lower in-cylinder pressure and a higher heat release rate compared to diesel. The mass fraction burned results of SFO biodiesel blends were found to be slightly faster than those of diesel. The SFO biodiesel 5% blend produced about 1.9% higher NOx emissions and 17.4% lower unburnt HC with 23.4% lower particulate matter (PM) compared to diesel fuel. To summarise, SFO biodiesel blends are recommended as a suitable transport fuel for addressing engine emissions problems and improving combustion performance with a marginal sacrifice of engine efficiency. [ABSTRACT FROM AUTHOR]

An experimental set-up was used to visually observe the characteristics of bubbles as they moved up a column holding xanthan gum crystal suspensions. The bubble rise characteristics in xanthan gum solutions with crystal suspension are presented in this paper. The suspensions were made by using different concentrations of xanthan gum solutions with 0.23 mm mean diameter polystyrene crystal particles. The influence of the dimensionless quantities; namely the Reynolds number, Re, the Weber number, We, and the drag co-efficient, cd, are identified for the determination of the bubble rise velocity. The effect of these dimensionless groups together with the Eötvös number, Eo, the Froude number, Fr, and the bubble deformation parameter, D, on the bubble rise velocity and bubble trajectory are analysed. The experimental results show that the average bubble velocity increases with the increase in bubble volume for xanthan gum crystal suspensions. At high We, Eo and Re, bubbles are spherical-capped and their velocities are found to be very high. At low Weand Eo, the surface tension force is significant compared to the inertia force. The viscous forces were shown to have no substantial effect on the bubble rise velocity for 45 < Re < 299. The results show that the drag co-efficient decreases with the increase in bubble velocity and Re. The trajectory analysis showed that small bubbles followed a zigzag motion while larger bubbles followed a spiral motion. The smaller bubbles experienced less horizontal motion in crystal suspended xanthan gum solutions while larger bubbles exhibited a greater degree of spiral motion than those seen in the previous studies on the bubble rise in xanthan gum solutions without crystal.

A noticeable variation is present among the guava (Psidium guajava L.) genotypes available in Bangladesh. Thirty-three (25 indigenous, 5 released, and 3 exotic) genotypes of guava were used in ex-situ conditions from different locations of Chattagram, Brahmanbaria, Pirojpur, and Gazipur districts and assessed based on 10 traits to know their genetic diversity. The measured traits were number of flowers, fruits, harvested fruits per plant, single fruit weight (g), number of seeds/fruits, thousand seed weight (g), vitamin C, total sugar content, and fruit yield/plant (kg). Twenty-one genotypes showed 100-400 g of single fruit weight, and 12 showed 20-100 g. The genotype G14 (BARI Peyara-1) produced the highest fruit yield/plant (131.04 kg) followed by G24 (PG Muk-005) and G23 (PG Muk-005) yielded 65.49 kg and 64.62 kg, respectively. Twenty-one genotypes showed above 250 mg/100g vitamin C content. Above 42% (14 genotypes) contained total sugar content of over 5%. The first two axes accounted 58.8% of the total variation among 10 traits. Based on the heatmap analysis, cluster-IV represents a high value containing the number of flowers, fruits, and harvested fruits per plant. The genotypes G14, G17 (BARI Peyara-4), G21 (PG Sit-003), G23, G24, and G29 (Thai Peyara-3) might be considered the best based on the morpho-biochemical characteristics. Many traits are of significant economic importance and could be used as breeding targets to increase yield and quality. Therefore, variation among guava genotypes will be an excellent source for future crop improvements. [ABSTRACT FROM AUTHOR]