Search Results (4)

Fiber extractors, as process-intensified equipment, facilitate many applications, such as the purification of oils. The development of high-fidelity computational models is crucial to optimize the design. However, simulating microscale flows around tens of thousands of microfiber arrays is computationally unfeasible. Thus, it is necessary to identify smaller elements, consisting of only a few fibers, that can represent flow within massively arrayed fiber extractors. This study employed computational fluid dynamics to investigate different configurations of four-fiber elements to achieve this aim. Following previous modeling featuring flow around only one fiber, the goal was to understand how variations in inter-fiber distances affect the phase structures of a corn oil/water mixture, the steady-state interfacial surface area per unit of fluid volume, and the pressure drop along the flow direction. The study explored various total and relative flow rates and contact angles. The research characterized the flow as semi-restricted annular, noting the influence of neighboring fibers on phase complexity. The inter-fiber distance played a crucial role in generating high interfacial areas and reducing pressure. The chaotic nature of the slug interfaces facilitated intermixing between flows along different fibers. Interestingly, the specific interfacial area reached an optimum when the inter-fiber distance was between 10 and 50 μm. Full article

This study aimed to evaluate the influence of gibberellic acid on both concentration and time of application on the seed production ability of BU cauliflower-1. The experiment was conducted to determine seed production ability at five concentrations of GA₃: G₀ = Control, G₁ = 100 ppm, G₂ = 200 ppm, G₃ = 300 ppm, G₄ = 400 ppm, along with four application times at different growth stages including T₁ = Foliar application at 3 weeks after planting, T₂ = Foliar application at 4 weeks after planting, T₃ = Foliar application at 5 weeks after planting and T₄ = Foliar application at 6 weeks after planting. Results revealed that 200 ppm GA₃ gave the highest plant height (44.05 cm), the number of primary (10.88) and secondary flowering branches (31.33), stalk length (79.53 cm), seeded pods per plant (465), pod length (4.975 cm), seeds per pod (10.87), seed yield per plant (16.16 g), seed yield (0.24 ton/ha), and weight of thousand seeds (4.826 g) with the earliest curd (51.02 days) and flower initiation (84.17 days). It also gave the highest net return (Tk. 4.7 lakh/ha) and benefit-cost ratio (4.34). GA₃ application at 3 weeks after transplanting had the highest numbers of primary and secondary flowering branches, pods, seeded pods, and seed yield per plant. The treatment combination of G₂T₁ gave the earliest curd initiation (49.60 days), the highest number of secondary flowering branches (34.87), seed yield per plant (22.75 g), and seed yield (0.27 ton/h). In contrast, the G₂T₂ treatment resulted in the earliest flower initiation (81.77 days) with the highest pod length (5.20 cm), the number of pods per plant (707), and seeded pods per plant (507), and seeds per pod (11.30). Hence, 200 ppm GA₃ applied three weeks after transplanting could be used as the best combination for cauliflower seed production with the highest net return and benefit-cost ratio. Enhancing seed yield is our ultimate goal; hence, we suggest 200 ppm GA₃ three weeks after transplanting for increased cauliflower seed production with the highest return and benefit-cost ratio in the study area. As we performed the study in a particular location, we recommend multilocation trials in different agro-ecological regions to study the genotype–environment interaction for final confirmation of the results. Full article

The aim of the paper is to give an overview on the chemistry of soil organic carbon (SOC) affecting nutrient availability, the emission of greenhouse gases and detoxifying harmful substances in soil. Humic substances represent the stable part of SOC, accounting for between 50 and more than 80% of organically bound carbon in soil. Humic substances strongly affect the soil solution concentration of several plant nutrients and may increase P-, Fe-, and Cu- solubility, thereby increasing their plant availability. Soil organic carbon, mainly humic substances, can detoxify monomeric Al in acid soils, can strongly bind toxic heavy metals, making them unavailable to the plant roots, and may strongly bind a vast variety of harmful organic pollutants. Increasing SOC is an important goal in agriculture. The inclusion of mixtures of semi-perennial plant species and cultivars may strongly increase SOC and humic substance content in soils. To increase SOC, farmyard manure and its rotted or composted forms are superior compared to the separate application of straw and slurry to soil. The storage of carbon, mainly in organic form, in soils is very important in the context of the emission of greenhouse gases. Worldwide, soils release about 10 times more greenhouse gases compared to fossil fuel combustion. Small increments in SOC worldwide will strongly affect the concentration of atmospheric CO₂. The public discussion on soil fertility and greenhouse gas emissionshas been politically controlled in a way that leaves the important and positive contribution of soil organic carbon and mainly humic substances partly misinterpreted and partly underestimated. Full article

Most countries have active road safety policies that seek the objective of reducing deaths in traffic accidents. One of the main factors in this regard is the awareness of the safety measures, one of the most important being the correct usage of the seat belt, a device that is known to save thousands of lives every year. The presented work shows a VR-enhanced edutainment application designed to increase awareness on the use of seat belts. For this goal, a motorized rollover system was developed that, synchronized with a VR application (shown in a head-mounted display for each user inside a real car), rolls over this car with up to four passengers inside. This way, users feel the sensations of a real overturn and therefore they realize the consequences and the results of not wearing a seat belt. The system was tested for a month in the context of a road safety exhibition in Dammam, Saudi Arabia, one of the leading countries in car accidents per capita. More than 500 users tested and assessed the usefulness of the system. We measured, before and after the rollover experience, the perception of risk of not using the seat belt. Results show that awareness regarding the use of seat belts increases very significantly after using the presented edutainment tool. Full article