Optimization of diesel engine input parameters running on Polanga biodiesel to improve performance and exhaust emission using MOORA technique with standard deviation

Fast exhausting fossil fuel reserves and high rise in the air pollution levels due to combustion of these fuels bound us to discover some cleaner and environment-friendly fuels for the engines. Biodiesel from edible and non-edible seed oils has been identified as a better alternate of the diesel fuel in engines with a little sacrifice in terms of power output but with an improvement in exhaust emissions. The aim of the present research work is to optimize the input parameters of diesel engine running on Polanga biodiesel to improve performance and exhaust emissions. The input parameters selected for optimization are fuel injection timing, fuel injection pressure, Polanga biodiesel blend, and engine load with respect to brake thermal efficiency, brake specific fuel consumption, hydrocarbon emission, smoke opacity, and emission of nitrogen oxides. Relative weights of the response variables were calculated by standard deviation. The optimum combination of input parameters was obtained by Taguchi-based Multi-Objective Optimization by Ratio Analysis. Experiments were performed according to Taguchi’s L₁₆ orthogonal array in a random manner in which three replicates of each experiment were noted. The optimum combination of input parameters for maximum performance and minimum exhaust emissions found to be as fuel injection timing 27° bTDC, fuel injection pressure –? 220 bar, biodiesel blend –? B40, and engine load –? 60%. The optimum values of the response variables, at the obtained optimum combination of input parameters, were predicted by Taguchi method and then verified experimentally and a good relation was found between them. These optimum values found to be as brake thermal efficiency –? 36.351%, brake specific fuel consumption –? 0.322 kg/kW-h, hydrocarbon emission –? 2.193 ppm, smoke opacity –? 80.925 HSU, and NO_x emission –? 690.987 ppmv.     

Polarity-Based Solvents Extraction of Opuntia dillenii and Zingiber officinale for In Vitro Antimicrobial Activities

Extracts from dried stem of Opuntia dillenii and rhizome of Zingiber officinale were evaluated for antimicrobial activities by extraction in non-polar (petroleum ether and chloroform) and polar solvents (methanol and water). Bacillus subtilis and Staphylococcus aureus showed considerable susceptibility to all extracts of Opuntia dillenii and Zingiber officinale. Ether and chloroform extracts of Opuntia dillenii showed improved antimicrobial activity against Escherichia coli (gram negative) as compared to that of its methanolic and water extracts. On the other hand, methanolic and water extracts of Zingiber officinale showed better susceptibility for Escherichia coli. Salmonella typhi (gram negative) was found to be resistant to all extracts of both Opuntia dillenii and Zingiber officinale. Our results indicated that both Opuntia dillenii and Zingiber officinale have potent antimicrobial activity that is also based on solvent polarity during extraction.     

Merit Figures for the Optical Design of CSP Plants

This work proposes some optical merit figures useful for solar concentration in the phase of optical design. The examined systems are CSP （concentrated solar power） plants with heliostats fields. In order to characterize them, it is suggested to use some optical merit figures, applicable to every CSP plant and synthetize its optical performance. The proposed merit figures have the aim of assessing mirrors field efficiency and receiver optical efficiency. In particular, they are identified using a new definition of the input flux on the mirrors field. The practical advantage of using the optical merit figures is illustrated by means of a simulation.     

Paper-Based Printed Antenna: Investigation of Process-Induced and Climatic-Induced Performance Variability

Printing technologies have emerged as a viable method for the fabrication of various electronic components, including sensors, actuators, energy harvesters, thin-film transistors and circuits, as well as antennas. However, printing processes have limitations in terms of surface roughness and thickness. Printing conductive structures on novel substrates, such as cellulose-based sustainable paper, also leads to further challenges linked to the high surface porosity and ink carrier absorption. Herein, the variability of paper-based printed antenna performance due to different printing processes, ink carrier absorption, and temperature is investigated. The resonance frequency and gain of different printed antennas (e.g., screen, inkjet, and dispense-printed) are compared in terms of surface roughness, thickness, and resonance frequency. Screen-printed antennas show better performance compared to other printed antennas. The results show that the resonance frequency of antenna shifts 20, 30, and 50 MHz for screen printed, dispense printed, and inkjet printed respectively, from the nominal 2.6 GHz. In the case of the inkjet-printed antenna, a clear effect of skin depth is observed, due to the 0.91 $\text{μm}$ thickness. Furthermore, it is demonstrated that the permittivity/dielectric constant of the paper substrate is significantly influenced by ink carrier absorption and temperature variance.