European Journal of Applied Sciences

Exhaust Gas Temperature Margin of A Jet Engine Cause Impact and Simulation

Sandeep Prajapati — 2026-03-09

When a jet engine starts, the temperature starts to increase within a range. At various durations of the engine run, there is some temperature. Higher the thrust, higher the heat. This temperature is called Exhaust Gas Temperature. Each type of engine has a maximum allowed exhaust gas temperature and the difference between the actual gas temperature and the maximum temperature is called the Exhaust Gas Temperature Margin. Airlines struggle to know which components should be replaced to obtain desired Exhaust Gas Temperature Margin. Formula for EGT Margin is EGT Margin = EGT Red Line – EGT Take off. Every airline aims to obtain a margin as high as possible. If the margin is very low, it is unsafe to use the engine and it could lead to fire in the engine. The article explains the root cause of lower margin, factors impacting the margin, what can be done to maintain a good margin and what must be avoided at all costs for the safety of the aircraft engine. Currently, there are no directions or guidelines on what engine components can be replaced to improve EGT Margin. The article shows how the simulation data was captured and what methodology was used to obtain the data.

A Review of Polarized Light Microscopy in Food Science

Howard J. Swatland — 2026-03-09

Some of the basic principles of polarized light microscopy are explained, followed by the problems involved in making automated measurements for meat samples with automated pH changes. Polarized light microscopy is then applied to meat samples on a tilting microscope stage to separate diffuse subsurface reflectance from the gloss of surface reflectance, to explain what is happening when a slice of meat is examined at the macro level in a conventional colourimeter. When meat is cooked, tough connective tissues may be gelatinized, thus increasing meat tenderness. This may be detected by a loss of birefringence using a polarizing microscope. The optical basis of starch granules in polarized light is explained as an interaction of the radial crystalline structure of starch interacting with the rectilinear orientation of a microscope polarizer and analyser.

Biodiesel Production from Waste Cooking Oil using Modified Poultry Droppings as Catalyst. Response Surface Methodology, Artificial Neural Network, and Extreme Gradient Boosting as Modeling and Optimization Tools

David Ohimai Ahonkhai — 2026-03-09

Poultry droppings was modified with nickel sulphate for the synthesis of biodiesel from waste cooking oil (WCO) with 6.43 % free fatty acid. The catalyst modified was characterized using Brunauer Emmet Teller (BET), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy and Energy dispersive X-ray (SEM-EDX), X-ray diffraction (XRD), and X-ray fluorescent analysis (XRF). Response surface methodology (RSM), artificial neural network (ANN), and extreme gradient boosting (XGB) were employed in modeling and optimizing the process conditions. Box-Behken design (BBD) of four process variables was used in designing the experiment. The biodiesel produced was characterized and its properties compared with established standards. The reusability potential of the catalyst was also assessed. The catalyst characterization revealed high surface area of 355.36 m²/g. Acidic and basic oxides such as CaO, SiO₂, NiO, SO₃, Al₂O₃ and Fe₂O₃ in significant quantities were found present indicating its bi-functionality. Optimum biodiesel yield of 96.82 % was obtained with methanol/oil ratio of 12.98:1, catalyst loading of 3.66 wt.%, temperature of 59℃, and reaction time of 86.45 minutes. RSM, ANN and XGB model were found to be efficient in modeling biodiesel production process with XGB performing best with the highest R² value of 0.9915. The properties of biodiesel produced were within the acceptable limits when compared with ASTM D6751 and EN 14214 standards.