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Comprehensive review of organic additives properties and their effects on characteristics of performance and emissions in diesel engines

Alaa Abdelrahman, Abdelhafiz Mahmoud, Amin Mohamed, Shahin Moatassem, Gaber Mohamed

Zeszyty Naukowe. Transport / Politechnika Śląska

2025

z. 128

27--49

Recently, organic additives have shown an essential role in improving fuel quality, promoting combustion efficiency, and minimizing pollutants. This research examines the properties and effects of several organic compounds on the performance and emission characteristics of diesel engines. The review results emphasize its impact on engine performance parameters, including power production, thermal efficiency, and fuel economy, as well as decreases in emissions of particulate matter, nitrogen oxides, and hydrocarbons. Challenges of optimizing additives and progress in cleaner combustion technologies are discussed. This study also demonstrates different suggested mechanisms for organic additives effect on engine performance and environmental sustainability; moreover, future research directions are introduced.

Effect of air entraining and pumice on properties of ultra‑high performance lightweight concrete

Zeyad Abdullah M., Amin Mohamed, Agwa Ibrahim Saad

Archives of Civil and Mechanical Engineering

2024

Vol. 24, no. 1

art. no. e11, 2024

This study focuses on developing the production of ultra-high-performance lightweight concrete (UHPLC) by combining pumice with an air-entraining agent. Air-entraining agents of aluminum powder (AP) and lightcrete (LC) were added in amounts of 0.1, 0.2, 0.3, 0.4, and 0.5% by weight of cement to create air bubbles. Crushed pumice has also been used as a partial sand replacement in proportions of 25% and 50% by volume, with or without the addition of AP or LC. To investigate the fresh, mechanical, and microstructural properties, seventeen UHPLC combinations were constructed. A slump flow diameter test was conducted to evaluate the characteristics of fresh UHPLC, and mechanical properties were evaluated by completing dry density, compressive strength, tensile strength, flexural strength, modulus of elasticity, and dry shrinkage tests. The effect of high temperatures of 20, 400, 600, and 800 °C on compressive strength was also investigated. The microstructure characteristics were analyzed using a scanning electron microscope. The research concluded that high-performance concrete with a compressive strength of 127.6 MPa and a dry density of 1970 kg/m3 could be produced after a 28-day age test. This was accomplished by including 0.1% LC by weight of cement and 25% pumice as a partial substitute for sand. The mixture with 50% pumice as a partial replacement for sand and the addition of 0.5% LC of the cement weight exhibited the least loss in compressive strength when subjected to high temperatures.