Sirte University

Rapid population growth has exacerbated freshwater scarcity worldwide. In India, particularly in arid and semi-arid regions like Rajasthan and Gujarat, water shortages are becoming increasingly severe, leading to a greater reliance on desalination and other purification methods. However, the rising cost of distillation due to sharp increases in fossil fuel prices has made the process less viable. Solar stills offer a sustainable solution for desalination, yet the quest for the most efficient solar distillation technique continues. Therefore, this study focuses on enhancing the performance of a modified semi-cylindrical solar still (MSSS) using four different experimental setups: MSSS1 (aluminum fins), MSSS2 (iron wick), MSSS3 (marble pieces), and MSSS4 (stainless steel curl strips). Performance was analyzed based on energy, exergy, economic, exergoeconomic, exergoenvironmental, enviroeconomic, exergoenviroeconomic, embodied energy, CO2 emissions, and CO2 mitigation parameters. MSSS4 outperformed all setups, achieving 47.08% higher productivity than MSSS1 and improving overall efficiency by up to 32.96%. It also had the lowest cost per liter ($0.00832) and reduced CO2 emissions by 12.44% compared to MSSS1. Additionally, MSSS4 led to the highest revenue and CO2 mitigation improvements, making it the most effective design.

This study is conducted to look at the enhancement of the mechanical properties and thermal stability of recycled polyethylene (RPE), polypropylene (RPP) and their blends with the addition of styrene butadiene rubber (SBR). Mechanical properties include Shore hardness and impact strength, as well as thermal properties such as thermal stability, were all evaluated. The addition of SBR increased the impact strength of RPP (by 17%) and all RPP/RPE blends (by 34% to 123%). With adding SBR, the impact strength properties of the PP-rich blend were considerably improved in comparison to RPP, RPE, and other blends. With blends, the improvement in impact strength decreased as the RPP component was decreased. On the other hand, the addition of SBR resulted in a decrease in the impact strength of RPE (by 21%). Additionally, the hardness properties were not apparent affected by the addition of SBR in all cases. In line with the impact strength findings, RPP and all RPP/PE blends showed a slightly increased hardness (by 1%–3%) after the addition of SBR, whereas RPE exhibited decreased hardness (by 2%). In contrast to the impact strength results, the hardness increased as the content of RPE in blend composition increased. The thermal stability of RPP and all blends was clearly improved with the addition of SBR. Conversely, there was no improvement in RPE’s thermal stability with the addition of SBR. Overall, this study demonstrates that adding an elastomer, such SBR, could potentially enhance the mechanical properties and thermal stability of RPP and RPP/RPE blends.

Quantum-chemical methods offer a powerful tool to elucidate the structure, properties, and reactivity of heterocyclic aromatic organic compounds. This study explores the structural features and chemical behavior of a representative N-heterocyclic crystal, 1-(2,2-dichloro-1-phenylvinyl)-3-(hydroxymethyl)-1,3-dihydro-2H-benzimidazol-2-one. By combining crystallographic and quantum-chemical methods, molecular geometry, noncovalent interactions (NCIs), and reactivity of both monomeric and dimeric forms of this compound have been investigated. The solid-state structure was found to be governed by a network of intermolecular interactions, including strong O–H···O hydrogen bonds, unconventional C–H···O and C–H···Cl hydrogen bonds, and π-interactions (C–H···π and π–π). Multiapproach quantum mechanics analysis based on dispersion-corrected density functional theory (DFT-D/ωB97X-D/aug-cc-pVTZ) revealed the electronic properties, energetics, and nature of these NCIs. Furthermore, conceptual DFT global reactivity indices identified the studied molecule as a moderate electrophile and strong nucleophile in polar organic reactions, while Parr functions method uncovered preferred sites for electrophilic and nucleophilic attacks.

A novel organic‐inorganic ferrate (III) hybrid compound, bis(8‐hydroxyquinolinium) tetrabromoferrate (III) bromide [(8‐HQ)₂FeBr₄]Br, was synthesized at room temperature via the slow evaporation method. Single‐crystal X‐ray crystallography, coupled with Hirshfeld surface analysis, revealed that the noncovalent hybrid assembly is governed by classical (O─H···Br and N─H···Br) and unconventional (C─H···Br) hydrogen bonding, as well as π‐stacking interactions. Notably, a unique Anion···π interaction between the [FeBr₄]⁻ anion and the hydroxyquinoline heterocycle was observed. Furthermore, a multi‐approach quantum mechanical method with dispersion‐corrected DFT (ωB97X‐D/aug‐cc‐pVTZ) was employed to analyze all identified noncovalent interactions, providing insights into their strength and nature. In addition, vibrational characteristics and optical properties were investigated using Infrared and Raman spectroscopies, as well as UV–visible and photoluminescence (PL) techniques. Finally, frontier molecular orbital (FMO) and Mulliken charge analyses were performed to determine the electronic features of the compound. A strong agreement was found between the experimental and theoretical findings.

Multiuser Multiple Input Multiple Output (MU-MIMO) wireless communication systems significantly enhance mobile cellular networks by employing Direction of Arrival (DOA) algorithms and beamforming (BF) techniques. These technologies enable the prediction of sidelobe signal directions, allowing for redirection toward specific desired targets. This research presents various adaptive DOA algorithms designed to improve wireless network performance. The study thoroughly examines DOA algorithms, including Multi-Signal Classification (MUSIC), Minimum Norm (Min-Norm), Minimum Variance Distortionless Response (MVDR), and Bartlett algorithms, comparing them based on angle estimation and peak power spectrum. The paper also discusses the concept of separating incoming signals into the Signals of Interest (SOI) and Signals Not of Interest (SNOI). Additionally, several BF algorithms, such as Least Mean Square (LMS), Recursive Least Square (RLS), and Constant Modulus Algorithm (CMA), are explored and evaluated. The research assesses the impact of BF algorithms on Bit Error Rate (BER) with varying numbers of antenna elements at the base station (BS). Simulation results indicate that while the algorithms demonstrate similar capabilities for interference cancellation, they differ in peak power values and beam widths. Furthermore, the accuracy of angle scanning and interference reveals that the algorithms have unique effects on directivity and gain, with the RLS algorithm showing slight improvements over the SMI and CMA algorithms. The findings highlight that the selection of beamforming algorithms, along with the number of antenna elements, significantly affects BER performance.

The contact between the sample and the AFM tip causes distortions in all atomic force microscope (AFM) pictures. With the three-dimensional tip form in hand, the distorted picture may be straightened out and the surface structure's original state "restored" using deconvolution methods. Compared to the initial distorted image, the restored image provides a more realistic portrayal of the sample's true 3D surface. In order to estimate the impulse response of the AFM, this work presents a new method that uses contact mode AFM to measure the dimensions of a micro-cylinder. Subsequent AFM pictures are subsequently restored using the predicted impulse response.

Due to the fact that mechanical properties in macroscale cannot respond to that of cell wall features, it has become important to investigate nanomechanical characteristics of scaffold materials and make suitable modifications if needed. Conventional methods of mechanical testing cannot characterize the spatial distribution of material, with non-uniform stiffness, at nanoscale. One of the important methods of nanoscale testing is the force mapping using the atomic force microscope. In the present study, A comprehensive approach was developed to determine and characterize surface distribution of elastic modulus for soft biomaterials at nanoscale. Elastic modulus has been determined for collagen fibers, modified with different percentage of bio-glass nonoparticles, 0%, 30% and 60%, by applying tiny forces (1 nN). The experiments are carried out in phosphate buffer saline (PBS) pH ~ 7, to mimic the physiological environment. The scanning was performed at two different spots for each sample and three different scan sizes to investigate the large scale and short scale heterogeneity, respectively. Deep-lying structures have been sensed by varying applied load (2 nN). Our results are in agreement with previous reports. The results show increasing elasticity with increase of bioglass in collagen samples. Yet adding more bioglass decreases the stiffness of collagen fibers to the point where they become difficult to handle. Samples appear to be strongly heterogeneous with increasing the scan size. The depth sensing measurements manifest higher elasticity which reflects the lower degree of freedom in the deep-lying structures.

A BSTRACT Introduction Stresses tend to vary depending on the kind of implant material (titanium or zirconium) because of differences in their mechanical and physical characteristics. Objectives The current research was done to assess the peri-implant stresses around zirconium and titanium dental implants using finite element analysis. Materials and Method Three distinct implant configurations were used to create three-dimensional finite element models (M1, M2, and M3) using ANSYS (11.0 Version) software, a P4 CPU running at 3 GHz, and hardware with three gigabytes of RAM. These configurations are typical for zirconium and titanium implants. Under 250 N of axial force and 50 N of nonaxial load, the stress surrounding the implants was examined. Result When compared to titanium implants, zirconium implants displayed higher strains in cancellous bone and lower stresses in cortical bone. Overall, titanium implants caused larger stresses in the bone than zirconium implants. Conclusion Compared to titanium implants, zirconium implants resulted in reduced peri-implant stresses.

This study analysed forty-six soil samples from the top 15 cm (6 in.) of urban soil in Tripoli, Libya for heavy metal contamination using atomic absorption spectrometry. The metals assessed included cadmium (Cd), lead (Pb), zinc (Zn), copper (Cu), nickel (Ni), cobalt (Co), iron (Fe), manganese (Mn) and chromium (Cr), with average concentrations of 3.94±1.93, 38.17±11.67, 170.94±62.68, 29.67±8.00, 19.70±8.75, 30.38±10.68, 27.444.52±8,739.15, 233.82±48.24, and 195.92±61.37 mg.kg-1.dwt (1.4E-4±7.0E-5, 1.35E-3±4.1E-4, 6.03E-3±2.21E-3, 1.05E-3±2.8E-4, 6.9E-4±3.1E-4 ,1.07E-3±3.8E-4, 0.97±3.08E-1, 8.25E-3±1.7E-3 and 6.91E-3±2.16E-3 oz.lb.-1.dwt), respectively. Most of these levels exceeded the permissible limits set by the World Health Organization and typical background values. Pollution indices suggested that the soil ranged from unpolluted to moderately polluted, with Cd, Co, Cr, and Zn being of particular concern. Cadmium was found to be the primary contributor to ecological risk, mainly from anthropogenic sources. Principal component analysis identified four key components: PC1 was dominated by Cd, Pb, and Zn with moderate contributions from Cu, related to human activities; PC2 was dominated by Fe and Cr; PC3 by Ni and Mn; and PC4 by Co and Cu, primarily from natural sources.

Following inflammation and bone loss near the implant site, peri-implantitis develops. N-Telopeptide (NTx) and Calprotectin are abundant in the crevicular fluids found in that area, and are thought to be possible biomarkers. Therefore, it is of interest to evaluate the amounts of calprotectin and NTx in the peri-implant sulcular fluid (PISF) from implant sites with or without peri-implantitis. Twenty healthy individuals and twenty patients with peri-implantitis who had a single dental implant were included in the total of forty participants. For every patient, the peri-implant clinical parameters of gingival index (GI), probing depth (PD), and bleeding on probing (BOP) were ted. To evaluate the bone loss (BL), radiographic pictures of every implant were acquired. Using sterile paper strips, PISF was gathered in order to use the ELISA technique to measure the amounts of NTx and calprotectin. We examined the correlations between the levels of PISF, NTx, and calprotectin with the peri-implant clinical indicators. In comparison to the healthy group, the peri-implantitis group had increased levels of NTx and calprotectin. In individuals with peri-implantitis, the levels of NTx and calprotectin in the PISF may be a promising indicator for bone loss and peri-implant inflammation.

Careful planning is essential for a successful outcome of dental implants. Determining the size of the implant and placement angle requires precise knowledge of the alveolar bone's height, width, shape, and density surrounding the intended implant location. Hence the goal of the current research was to use cone beam computed tomography (CBCT) to evaluate the anterior maxilla's bone state for dental implant insertion. The study included 30 patients, both male and female, who had CBCT scans of their anterior maxilla and needed dental implants in their maxillary anterior teeth. Measuring parameters included buccal undercut position and depth, as well as bone height and width. When comparing the canine region to the incisors, the mean bone height and width was higher. Buccal undercut, however, was more for the incisor region. The difference was statistically significant (P<0.05).

Photocatalytic water splitting is considered as one of the most promising technologies for hydrogen production. A novel 2D/2D/2D ZnCo2O4/g‐C3N4/Ti3C2 (ZCO/CN/TiC) nanocomposite was synthesized through a facile thermal method for efficient photocatalytic H2 production under visible light. This multi‐heterojunction system displayed an efficient performance with higher H2 production rates compared to single catalysts. The experimental results revealed a hydrogen production rate of 1465 µmol g⁻¹ for the ZCO/CN/TiC ternary composite after 4 h of light irradiation, which is about 3.8 and 2.5 times higher than that of g‐C3N4 and g‐C3N4/Ti3C2, respectively. This significant enhancement is mainly attributed to the efficient charge transfer within the constructed heterojunction system and due to the presence of MXene (Ti3C2), which acted as a solid electron mediator to suppress the charge recombination rate. Both the type and the amount of used sacrificial agent have exhibited a significant effect on the H2 production rate. The ZCO/CN/TiC ternary nanocomposite has also displayed the best quantum yield (QY = 1.316). The newly developed structured photocatalyst would provide a promising approach for the construction of easyprepared and noble‐metal‐free photocatalysts for the application of clean and sustainable fuel production.

Determining the optimal loading schedule and measuring implant stability at different times are critical tasks. Numerous tools have been created to assess implant-bone stability as a sign of a well-treated implant. Thus, the objective of this cross-sectional study was to estimate the validity of the Osstell ISQ system for assessing implant stability. Osstell ISQ was used to complete implant stability registers for 60 implants across 18 patients. Two distinct SmartPegs (types I and II) were used to complete six measurements on each implant, or three measurements in a row with each transducer. In the 1st, 2nd, and 3rdmeasurements with SmartPegs I and II, the average ISQ was 71.36, 71.31, and 71.65, and 71.02, 71.58, and 71.76, respectively. For SmartPegs I and II, equivalent values or variations below three ISQ points were found in 46.3% and 58.6% of the cases, respectively. Both SmartPegs had an intraclass correlation coefficient of 0.96, and they also had repeatability and reproducibility of 0.96. An intra-class correlation coefficient analysis reveals nearly excellent repeatability and reproducibility for the RFA system Osstell ISQ. Measurements of Osstell ISQ have excellent repeatability.

This study examines the effect of biochar as an agricultural soil supplement on soil quality indicators, specifically enzyme activity in Missouri regions. While the benefits of biochar on soil bulk density, soil organic carbon, and infiltration have been established, its effect on soil enzyme activity has remained underexplored in this region. A three-year field investigation was conducted with six treatments (compost, biochar, compost + biochar, biochar + compost tea, fescue, and control) to evaluate the effects on enzymes such as β-glucosidase (BG), acid and alkaline phosphatases (ACP-ALP), arylsulfatase (ARS), dehydrogenases (DG), arylamidase (AMD), cellulase (CLS), and urease (URS). Furthermore, soil pH, organic matter (OM), and cation exchange capacity (CEC) were determined. The results showed that compost and biochar treatments considerably increased soil enzyme activity compared to other treatments, with nitrogen application further increasing enzyme activity. Soil pH, OM, and CEC were all important determinants in determining enzyme activity, with BG demonstrating strong positive associations with ACP and AMD (99.5%). This study shows that compost and biochar amendments significantly improve soil physicochemical and biological properties, thereby enhancing soil health and assisting farmers’ sustainable soil management practices.

Background Restoring endodontically treated teeth has long posed a challenge for clinicians. The endocrown (EC) is an innovative and conservative restoration designed for teeth with severely damaged coronal structures. ECs offer performance that is equivalent to or even exceeds that of traditional post-core-crown treatments. Purpose This web-based cross-sectional survey aimed to evaluate the level of knowledge and practical experience regarding ECs as post-endodontic prostheses among dental students and practitioners in Libya. Methods A 22-item structured questionnaire was created using Google Forms and distributed to final-year students, interns, faculty at the College of Dentistry at Sirte University, and practicing dentists in Libya. The sample comprised 290 participants. The questionnaire was divided into three sections: the first assessed demographic variables such as gender, education level, country of graduation, and workplace; the second evaluated knowledge of ECs through 11 questions; and the third focused on EC practice, also comprising 11 questions. Statistical analysis was conducted using IBM SPSS Statistics for Windows, Version 21.0 (Released 2012; IBM Corp., Armonk, NY, USA). Results A total of 50.7% of participants indicated that EC restorations are suitable for molar teeth, 41.4% noted that a butt joint finish line is used for EC preparation, and 66.9% preferred all-ceramic materials for ECs. Nearly 72.8% reported that computer-aided design/computer-aided manufacturing technology is employed for EC fabrication. Additionally, 61.7% agreed that EC designs offer higher fracture resistance compared to conventional crowns. Despite this, 64.5% of participants had not cemented an EC in their clinic in recent years. Significant differences in knowledge and practice regarding ECs were observed across various factors, including gender, education level, country of graduation, and workplace. Conclusion Most participants demonstrated an acceptable level of knowledge and practical experience with EC restorations. Therefore, incorporating ECs as a major topic in the postgraduate prosthodontics curriculum is recommended.

Drawing on legitimacy theory and stakeholder theory, this study examines whether oil price uncertainty (OPU) affects corporate carbon performance (CCP) in the international context. Based on data extracted from CDP (previously known as the Carbon Disclosure Project), World Bank, and Thomson Reuters Eikon databases, the study's sample consists of 9074 firm-year observations over the period 2011–2018 for all non-financial multinational companies invited to take part in the CDP questionnaire. Using an ordinary least squares regression model, we identify a strong relationship between OPU and carbon emissions performance. Our findings are robust to a battery of sensitivity tests, all of which support our original results. This study contributes new knowledge regarding the influence of OPU on CCP. The results will be of interest to investors and policymakers as they provide a useful basis for understanding OPU and its impact on CCP to promote better decision-making.

This paper presents a comparative study on the effect of two local Libyan grasses, Stipa tenacissima (locally known as Halfa) and Retama raetam (locally known as R’tem) on the mechanical properties of styrene-butadiene rubber composites (SBR). For this purpose, the effect of filler type and content (10, 20, 30 and 40 wt%) on the mechanical properties of the composites including stress at break, elongation at break, impact strength and microhardness were evaluated. The stress at break of SBR increased only with the addition of 20 wt% and 30 wt% of Halfa. The highest value of stress at break was obtained by composites made with 20 wt% Halfa content. The elongation at break was significantly decreased with the addition of Halfa and R’tem. Generally, the elongation at break of the composites made with R’tem was slightly higher than that of composites made with Halfa. On the other hand, the addition of Halfa resulted in composites with relatively higher impact properties. The impact strength of these composites was increased with increasing the Halfa content up to 30 wt% after which it was decreased noticeably. However, the impact strength of composites made with R’tem did not follow a clear path with increasing R’tem content. Furthermore, the incorporation of Halfa and R’tem resulted in a significant increase in the hardness properties of the composites. R’tem showed to produce composites with higher hardness compared to those made with Halfa. Composites made with Halfa possess better toughness and ductility to a certain degree in comparison to composites made with R’tem. Although, Halfa appears to be relatively better than R’tem in reinforcing SBR, both fillers appeared to be good candidate filler to produce low cost and density polymer composites with acceptable mechanical properties.