High concentrations of radioactive elements are an indicator of the risk of radioactivity. The cesium radionuclide is one of the most important radionuclides. This study investigates the concentration and radiological impact of Cesium-137 (Cs-137) in surface soils within the Al-Zawiya region, Libya. A total of 19 soil samples were collected from various locations in September 2024, including areas near the Al-Zawiya oil refinery. Samples were prepared by drying, sieving, and sealing in Marinelli beakers for 30 days. Activity concentrations were determined using gamma-ray spectroscopy with an n-type HPGe coaxial detector system (GR6022). The specific activity of Cs-137 was calculated from the 661.66 keV photopeak, and corresponding absorbed dose rates and annual effective doses were derived using standard conversion factors. Cs-137 was detected in 9 samples (47.37%), with activity concentrations ranging from 0.1338 to 2.4037 Bq/kg and a mean of 0.6727 Bq/kg. The highest values were not associated with refinery infrastructure, indicating a fallout origin from historical nuclear events rather than local contamination. The resultant absorbed dose rates (0.0041 - 0.0721 nGy/h) and annual effective doses (0.0050 - 0.0109 μSv/year) are orders of magnitude below the public dose limit of 1 mSv/year and negligible compared to natural background radiation.

This research explores the fundamental principles of quantum computing and their application in enhancing communication security through Quantum Key Distribution (QKD) in free-space channels. Classical cryptographic methods face inherent limitations, particularly with the advent of quantum computational capabilities. Quantum mechanics, specifically the principles of superposition and entanglement, offers a robust framework for secure communication, ensuring that any attempt at eavesdropping inevitably perturbs the quantum state, thus revealing the intruder's presence. Through comprehensive simulations, this study analyzes the performance of QKD systems in free-space communication. Key parameters such as transmittance efficiency (𝜂𝑇), Quantum Bit Error Rate (QBER), and Secret Key Rate (SKR) are evaluated. Results indicate that transmittance efficiency in free space generally decreases with increasing zenith angle, with downlink scenarios (day and night) exhibiting higher efficiencies compared to uplink during the night. For all protocols, simulations demonstrate an increase in QBER and a corresponding decrease in SKR as the zenith angle increases, with downlink performance consistently surpassing uplink in terms of a higher SKR and a lower QBER.

A new mechanical framework is introduced to describe bodies with time-continuous mass

variation, incorporating a functional dependence on mass. In this approach, the dynamics

are governed by momentum balance equations formulated using Caputo fractional

derivatives, which adhere to a weak form of Galilean invariance. The formulation is

particularly focused on the Meshchersky kinetics, accounting for both mass and velocity

changes. As a practical example, this paper presents a novel model for the motion of a

material body with continuously varying mass in a constant gravitational field—leading to

a time-fractional version of the Tsiolkovsky rocket equation, augmented by a dissipative

term. Under time-based approximation, deviations from vertical projectile motion are

analyzed to assess the internal consistency of the proposed model.

A three-parameter generalization of the Tsallis entropy based on the properties of the power functions and Weyl fractional calculus like extension of quantum calculus, are introduced. The generalization of the Shannon-Khinchin axioms corresponding to the fractional Tsallis entropy is verified and proposed. These axioms uniquely characterize new entropy function. For a certain sets of parameter values satisfied the second and third law of thermodynamics, the Lesche and thermodynamic stability criteria.

ZnO thin films were deposited on stainless steel substrates using the immersion method by immersing the

substrates in a sol-gel coating solution at temperatures of 70 °C and 80 °C for varying durations of (1, 2, 3, and 4minutes).

The results indicated that increasing the immersion time significantly influenced the film thickness. Optical measurements

showed that transmittance at a wavelength of 350nm increased with higher deposition temperatures. Additionally, the

Urbach tail energy increased with temperature, whereas the band gap (Eg) decreased markedly. Furthermore, the

electrical conductivity of the ZnO films improved with increased temperature and immersion time.

ZnO thin films were deposited on stainless steel substrates using the immersion method by immersing the substrates in a sol-gel coating solution at temperatures of 70 °C and 80 °C for varying durations of (1, 2, 3, and 4minutes). The results indicated that increasing the immersion time significantly influenced the film thickness. Optical measurements showed that transmittance at a wavelength of 350nm increased with higher deposition temperatures. Additionally, the Urbach tail energy increased with temperature, whereas the band gap (Eg) decreased markedly. Furthermore, the electrical conductivity of the ZnO films improved with increased temperature and immersion time.

Thin films deposited on glass surfaces can be produced by various

methods, including physical methods (thermal evaporation in

vacuum, sputtering, etc.) and chemical methods (chemical

deposition, chemical vapor deposition, thermal chemical analysis,

etc.). In this paper, thin films were deposited on glass slides using

the plasma-enhanced chemical vapor deposition (PECVD)

technique at pressures (10,30 and 50 mTorr) for varying durations

of (5,10 and 15 minutes). In addition, the results indicates that

increasing the deposition time significantly influenced the film

thickness while the adhesion does not directly depend on time.

In this study, the morphological and thermal properties of a blend consisting of 75% polyvinyl chloride (PVC) and

25% low-density polyethylene (LDPE), reinforced with nano-refractory bricks (NRB) at varying ratios (1%, 3%, 5%, and 7%),

were prepared and investigated. The objective was to enhance the blend’s thermal stability and surface structure homogeneity.

The morphological structure of the prepared samples was analyzed using scanning electron microscopy (SEM) and X-ray

diffraction (XRD). The obtained images revealed that the nano-refractory brick particles remained predominantly within the

PVC phase, resulting in an increased composite density without significantly affecting the LDPE phase. This suggests that the

overall morphology of the composite is largely unaffected by the presence of the nano-refractory bricks. From a thermal

perspective, thermogravimetric analysis (TGA/DTG) was conducted on all samples from room temperature up to 600 °C at a

heating rate of 10 °C/min. FTIR and TGA results indicated that the decomposition onset temperature shifted to higher values

due to the presence of nano-refractory bricks, with the most pronounced shift observed in the sample containing 3%

reinforcement. Additionally, the rate of mass loss was reduced. These findings demonstrate that reinforcing the PVC/LDPE

blend with nano-refractory bricks improves its performance, making it more suitable for applications that demand enhanced

thermal and mechanical properties, such as those in the construction and electronics industries.