No abstract

Technology of ultrasonic atomization has been proven effective at creating droplets with specific physical and functional properties. Applications of this technology include drying liquids, medical nebulizers for inhalation therapy, surface coating, and encapsulation of materials in particles for therapeutic medicine, nutritional food, energy production and imaging. Parameters studies in this literature reviews are related with correlation of frequency values, droplet size, and flow rate of liquid, as well as the temperature resulting from the breakdown of molecules through the transducer droplet particle size and evaporation rate also need to be considered because it is related to the effectiveness of uptake nutrients in the roots. This article provides an overview of the primary mechanisms arising from ultrasonic responsible for the formation of these materials, highlighting examples that show promise particularly in the development of aeroponic system and bioproducts.

Thermal Efficiency of Organic Rankin Cycle (ORC) Power Plant System from low-grade heat resources using various working fluids has been analyzed based on the simulation. Four working fluids, namely R-134a, R-32, R-407A, and R-422C were selected on the simulated ORC system to determine its thermal efficiency in some temperature set up of evaporator and condenser. The working fluids are simulated with mass flow rate of 0.15 kg/s at evaporator exit temperature of 75°C, 80°C, and 85°C and at condenser exit temperature of 20°C to 50°C at each 5°C temperature difference. Fluid properties in these conditions are analyzed with REFPROP software then become data input for Cycle Tempo simulation. The thermal efficiency values of each temperature and refrigerant variation are then analyzed to obtain optimum value and variation for the simulated ORC system. The efficiency was obtained at the evaporator exit temperature of 75°C and condenser exit temperature of 45°C. ORC simulation revealed that the optimum and realistic working fluid was R-32 with thermal efficiency of 7.03 %.

True Seed Shallot (TSS) is the planting material beside bulbs that farmers in Indonesia have used. TSS give some benefit for farmer technically and economically. However, the farmer’s utilization of TSS is not used widely yet because there are constraints on the provision of shallot seeds from TSS, such as low seed growing percentage and seedling performance. This study aims to obtain the best seedling performance of shallot from TSS with LCAC (Low-Cost Aeroponic Chamber) technology. The experiment was conducted at the Plant Factory and Screen House, Leuwikopo, Department of Mechanical and Biosystems Engineering, IPB University, July to October 2021. The germination was carried out for seven days. After that, the shallot seedlings have given light source treatments. The factor was light sources, i.e., screen house (sunlight; as a control; used wick system hydroponic), white light, red-blue light, and custom light (LED in a controlled room with LCAC). The performance shallot seedling on sunlight source treatment gave the average plant height, the number of leaves higher than white, red-blue, and custom light on 3 and 4 weeks after sowing. The white light treatment gave the chlorophyll-a, chlorophyll-b, and total chlorophyll-a & b higher than the other light source treatments.

The decline in the productivity of shallots occurred in almost all areas of shallot production centres in Indonesia. One of the factors in the decline in productivity is that farmers are still dependent on tuber seeds that are produced by themselves from generation to generation without any risk of carrying degenerative diseases from previous shallots. Another problem is that the cost of providing seeds is quite high, reaching 40% of the total production cost, with an average requirement of 1-1.5 tons/hectare. Planting shallots using TSS (True Shallot Seed) is an alternative solution, in terms of seed requirements, only 3-5 kg/ha is needed. However, an initial activity is needed in the form of the production of shallot planting material before it is transferred to the land. This study aims to conduct a technoeconomic analysis of shallot planting material production from TSS with LCAC (Low Cost Aeroponic Chamber) technology. Techno-economic analysis is carried out by calculating the basic costs for producing shallot seeds, and economic analysis related to NPV, IRR, Net BC Ratio and Payback Period. This study uses a scenario design of production scales of 200, 500, 1000 trays, and 1 million seeds on a production schedule of 3 cycles per year and 6 cycles per year. The NPV calculation yields profits ranging from 4,750,650 - 822,448,953 IDR, IRR 9.87 - 65.40% above the discount rate used of 6%. Net B/C ratio 1.12 - 2.24 and initial investment will return to investors in the range of 5.23 to 1.28 years after production starts.