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Muons are usually among the most common secondary cosmic ray particles on Earth's surface. Muon research has confirmed their occurrence in a variety of locales. It has been claimed that cosmic radiation in general, and muons in particular, have disastrous consequences on biological things and electrical components on Earth and in space. According to medical sources, cosmic rays have been linked to many ailments affecting people and other creatures. Because of these issues, cosmic ray shielding has become a crucial component of this and comparative studies. Muons emitted by cosmic rays were detected using a muon telescope made of coaxial Geiger-Muller (GM) tubes. This experiment was carried out within the muon lab of Universiti Kebangsaan Malaysia (UKM) in Malaysia to examine how the cosmic ray muon count fluctuates with the shielding of metals (Copper (Cu) and Aluminium (Al)) and polyethylene. The measured muon count for each metal sample was statistically analysed. Using both metals as shielding in this experiment revealed that adding additional Cu and Al sheets reduced the muon count. Generally, the numbers drop as the thickness increases. The results suggest that Cu outperforms Al in shielding efficacy (19% vs 16%). Because Cu has a more significant density than Al, the correlation coefficient R 2 for Cu = 0.9372 is greater than R2 for Al = 0.6593, indicating that the trend for Cu is better than the trend for Al in this experiment. To study the shielding capabilities of the two composites, Al/PE and Cu/PE, ten sheets of Polyethylene (PE) were gradually put individually between the Al and Cu

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Abstract. This research aims to investigate the impact of employing various types of materials as partial cement replacements on the characteristics of high-strength concrete. As cement replacements, Nano SiO2 , Nano CaCO3 , micro SiO2 , micro CaCO3 , recycled silica gel (beads and powder), and limestone were employed, as well as binary combinations of (Nano SiO2 + Nano CaCO3 ), (micro CaCO3 + micro SiO2 ), and (recycled silica gel powder + limestone). In addition to the control mix, ten sets of concrete mixes were created with progressive cement replacement. Thermal analysis (TG-Thermogravimetric) and (DTG-Derivative Thermogravimetry) were employed to determine the CH content of each concrete group. The nano-silica mix had the lowest calcium hydroxide (CH) content, followed by the binary nano mix and crushed silica gel mix. In contrast, the other mixes had approximate values. Still, they were all less than the control mix, indicating that larger amounts of calcium silicate hydrate (CSH) gel formed after replacement, which has primarily contributed to improving the strength and durability of concrete

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The combination of a hard surface and a soft interior is greatly valued in modern engineering because it can withstand very high stress and fatigue, a property that is required in such items as gears, turbine blade and anti-friction bearings. Surface-hardened steel is also valued for its low cost and superior flexibility in manufacturing. This study looked at how the carbonization temp affected the resistance against wear and hardness of the steel alloy utilized to make turbine impellers. The specimens were activated in Co2 at each temperature for soaking at about 30, 60, 90, and 120 minutes. The carbonization temp was changed from 850, 900, and 950 to 1000C. The Carburized steels are put through various tests, including wear tests utilizing a pin on a desk, hardness tests utilizing a Brinell-hardness tester, and phase observations utilizing an EDX (Energy Dispersive X-Ray). The findings demonstrated that all carburizing temps improved resistance against wear, and the wear rate decreased with rising temp and prolonged immersion in the carburized medium, minimum wear rate founded at 1000C0 for 2hr as soaking time. Additionally, hardness exhibited the same upward trend in resistance against wear as temp and time and maximum hardness recorded at 1000C for soaking time of 2hr was 106BHN compared with plain material 56BHN. EDX analysis demonstrates that the carburizing process for all treated specimens creates an extra carbon phase.

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Helical gears, due to their increased contact region during the engagement cycle and consequent reduction in noise, have become ubiquitous in mechanical engineering applications and thus form the focal point of this study. This research paper meticulously examines the position of the helix angle and comprehensively evaluates its influence on the reaction force and its evolution on the gear shaft. The results reveal an optimal helix angle of 30 degrees, which minimizes the stress impact on the shaft. In contrast to the typical 40-degree angle, a reduced helix angle of approximately 5 degrees results in the largest displacement along the x-axis for gear 3 at a rotational speed of 590 rad/s, reaching up to 0.15 micrometers. Furthermore, the lowest percentage error can be observed at the 5-degree angle, with a maximum value of 0.8 degrees. A maximum reaction force of 1080 N is observed at a helix angle of 5 degrees, which increases further with the length of the helix. These results provide compelling evidence in favor of the 5-degree angle as opposed to significantly larger angles. The force exerted on the shaft, viewed from two distinct axes, and its temporal evolution are also meticulously examined, providing valuable insights into the dynamic stress of highspeed helical gears.

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In this article, an investigational analysis has been conducted to explore the effect of biodiesel fuel blends on characteristics of engine and releases (CO2, CO, HCl, and NOx) of single-cylinder, four strokes at the variable biodiesel concentration. The releases of gases and the engine's characteristics were measured at six blending biofuels and six-speed conditions and constant load. The blending proportions of biodiesel with diesel fuel-based by volume were at 0% pure diesel, 5%, 10%, 15%, 20%, and 25%. This investigation aims to assess the biodiesel fuel mixture's impact on the CI engine performance in terms of its Bsfc, Ƞbth, and engine release of CO2, CO, HCl, and NOx. The investigation revealed that biodiesel remarkably minimized the release of CO2, CO, HCl, and NOx. The influence of this fuel mixture was studied between 5% to25% biodiesel concentration, and the results of this investigation could aid in understanding the Impact of utilizing biodiesel as an energy source on engine releases and performances.