World Academy of Science, Engineering and Technology

Authors: Ragab A. A.

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Fatigue cracking is one of the most important forms of distress affecting the performance and service life of asphalt pavements. The interaction between heavy traffic loads and harsh aging conditions caused by prolonged exposure to hot climates significantly increases the risk of this distress. Asphalt binder plays a pivotal role in mitigating the propagation of fatigue cracking by enhancing its ability to flow and fill microcracks, a behavior referred to as self-healing of asphalt binders. Microencapsulation technology has proven effective in healing applications. These capsules are designed to contain a healing agent that can be released under specific conditions to facilitate the repair of cracked areas. This research aims to evaluate the effect of phase change materials (PCMs) on the self-healing properties, durability and performance of asphalt binders and pastes under different conditions. Initially, encapsulated PCMs were developed using paraffin oil (PO) as core material, encapsulated with nano-silica fume (NSF) as binder, with different core-to-binder ratios. A unique filler, NSF, was used for the paste formulations. The synthesized hybrid phase change material capsules (HPCMCs) were incorporated into asphalt binder and paste at different dosages (1%, 3%, 5% and 7%). To simulate aging, the asphalt binder and paste were subjected to short-term and long-term aging using a rolling thin film oven (RTFO) and a pressure aging vessel (PAV), respectively. The morphological, structural, thermal and chemical stability properties of HPCMCs were evaluated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) techniques. For physical characterization, the penetration properties and softening point of HPCMC-modified and unmodified asphalt binders were evaluated. Morphological characterizations of asphalt binders and pastes were performed using scanning electron microscopy and energy dispersive X-ray (EDX) analysis, while rheometric evaluations included rotational viscosity (RV), performance classification (PG), linear amplitude scanning (LAS) and linear amplitude scanning (LASH) based healing tests. Various stimuli such as mechanical loading, temperature fluctuations and humidity conditioning were used to facilitate the release of microcapsule contents. Low doses of 3-5% HPCMCs were found to enhance the performance of asphalt binders in terms of sintering resistance, fatigue life and healing behavior. Notably, NSF paste exhibited superior fatigue resistance.

Keywords: asphalt, capsule, self-healing, binders, phase change

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Authors: Faysal Fayez Eliyan

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Corrosion remains a significant challenge across various industries, leading to substantial economic losses and safety concerns. Traditional corrosion detection, prediction, and prevention methods rely on empirical models and experimental approaches, which can be time-consuming and costly. In recent years, artificial intelligence (AI) has emerged as a transformative tool in corrosion science, offering improved accuracy, efficiency, and predictive capabilities. This review explores the application of AI techniques—including machine learning, deep learning, and expert systems—in corrosion prediction, monitoring, and mitigation. Key AI-driven methodologies, their advantages over traditional approaches, and real-world case studies are discussed. The review also highlights challenges such as data availability, model interpretability, and computational complexity. Finally, future directions for AI in corrosion science are outlined, emphasizing the need for hybrid models, explainable AI, and real-time monitoring systems.

Keywords: corrosion science, artificial intelligence (AI), machine learning (ML), corrosion prediction

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Authors: Qianxing Huang, Shijie Yu, Jiaqi Cheng, Jianqing Jiang, QIyue Shao

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Phosphor-in-glass (PiG) is widely acknowledged as the most competitive all-inorganic color converter in the field of high-power solid-state lighting. Strong phosphor-glass interfacial diffusion induces the performance degradation of phosphors and impedes the progress of PiG-based white light-emitting diodes (WLEDs) in achieving high power, brightness, and efficiency. In this study, a distinct glass matrix (SiO₂-B₂O₃-Al₂O₃-CaO-Y₂O₃-Na₂O) specifically designed for Y₃Al₅O₁₂:Ce³+ (YAG:Ce³+) phosphors was proposed aiming to suppress interfacial diffusion. The design principles of the glass matrix primarily rely on confining the ionic diffusion through modulation of the glass coordination structure and reducing the concentration gradient at the glass-phosphor interface through the introduction of phosphor constituent elements into the glass matrix. Consequently, interfacial diffusion in the fabricated YAG: Ce³+-PiG was effectively suppressed, with an interfacial reaction zone width of less than 55 nm. As a result, the internal quantum efficiency of the YAG: Ce³+-PiG could maintain 97% of the original phosphor, while its fluorescence lifetime only decreased by 0.6 ns. The luminous efficacy of the WLED device fabricated by combining YAG: Ce³+-PiG and blue LED chip reaches up to 140 lm W-¹ under an input power of 3 W (1000 mA operation current). Additionally, the simultaneous incorporation of YAG: Ce³+ and CaAlSiN₃: Eu²+ phosphors into the glass matrix further enhances the white light quality of the WLED, resulting in a high color rendering index (CRI) of 92.6. The findings underscore the importance of rational glass composition design for PiG composites and will facilitate further improvements in the performance of PiG color converters for efficient high-power solid-state lighting devices.

Keywords: LED, phosphor in glass, Y₃Al₅O₁₂:Ce³+ , glass matrix design, interfacial diffusion

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Authors: Aradhana Sahoo

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Allyl amines are vital components in various biologically important molecules and play a significant role in their function. Presently, most methods are geared towards the preparation of di- and tri-substituted allyl amines, leaving a gap for the development of more versatile approaches. We herein describe an approach to yield tetrasubstituted allyl amines through palladium (Pd)-catalyzed regioselective dicarbofunctionalization of masked N-phthalimide protected propargyl amines. The cationic Pd-intermediate, in conjunction with the masked amine, exerts collective control for the reaction regioselectivity. This method accommodates a wide range of alkynes, aryl boronic acids, and aryl diazonium salts offering direct access to a wide range of unusual tetrasubstituted allyl amines.

Keywords: tetrasubstituted allyl amines, highly regioselrctive, directing group assisted, cationic palladium chemistry

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Authors: L. Hassaini, M. Fois, M. Kaci

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Biocomposites based on PHBV/PPF: 80/20 (w/w) with and without PHBV-g-MA were prepared by melt compounding. TGA data revealed an increase in thermal stability of PHBV/PPF biocomposites, being more pronounced in the presence of the compatibilizer, resulted in better dispersion of the filler in the matrix. Furthermore, dynamic mechanical measurements indicated a reinforcing effect of PPF in PHBV biocomposites. The presence of PHBV-g-MA compatibilizer in PHBV/ PPF biocomposite has almost no effect on the storage modulus; it remains almost unchanged after the addition of PHBV-g-MA.

Keywords: biocomposites, compatibility and relationships structure/properties, palm fibers, PHBV, PHBV-g-MA

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Authors: Moulay Driss Mellaoui, Bouchra Balkard, Hanane Zejli, Christophe Len

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This study explores the inhibition of mild steel corrosion in a corrosive medium of 0.5 M HCl using three different inhibitors: furan-2-carboxylic acid (P1), furan-2,5-dicarboxylic acid (P2) and furan-2,5-diyldimethanol (P3). Electrochemical techniques, including potentiodynamique polarization (Tafel curves) and electrochemical impedance spectroscopy (EIS), were used to assess their efficacy. Experimental results show that these inhibitors effectively reduce corrosion, achieving efficiencies of 97.56%, 99.55% and 95.82%, respectively, at a concentration of 5×10-³ M and at 298 K. The inhibitory efficacy (IE) of each compound increases with concentration, and all three inhibitors act as mixed inhibitors, as indicated by consistent electrochemical data. Theoretically, the molecular structures of the inhibitors (P1, P2, P3) were optimized using density functional theory (DFT) at the B3LYP/6-311++G(d,p) level in the gas and aqueous phases to assess their reactivity and stability. Among them, P2 shows the highest reactivity and stability with frontier molecular orbital energies (E_HOMO = -1.66 eV, E_LUMO = -1.72 eV). Electrostatic potential mapping (ESP) highlights potential reactive centers, while Fukui functions reveal sites of local reactivity, particularly for P2, which benefits from its larger molecular size. These results shed further light on the inhibition mechanism and open up new prospects for corrosion protection strategies.

Keywords: furan derivatives, corrosion inhibition, mild steel, EIS, surface morphology, DFT

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Authors: Rima Djezzar, Nora Seghairi, Zohra Djezzar, Khadidja Hamida, Imene Akacha

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Nitrate ions present in agricultural and agri-food effluents are the major cause of water pollution, leading to eutrophication and health risks due to methemoglobinemia. The treatment of these effluents before discharge is then imperative. Many biological and physicochemical processes have been implemented for the treatment. However, adsorption is a promising alternative due to its simplicity and speed. In this context, the main objective of the work presented is to study nitrate removal on biochar prepared by date stones (DSB). Biochar was prepared at different pyrolysis temperatures (700, 800, 900 and 1000 0C) in order to select the best biochar with the highest nitrate removal efficiency and determine the main characteristics, which were characterized by FTIR, MEB, and DRX. The adsorption results highlighted that nitrate was effectively removed (88.57%) when using DSB-1000 0 C, and it was more effective in domestic wastewater by 92%. This study contributes to paving the way for future investigations into the recovery of plant waste, namely date pits or other by operators in the field of water treatment by the adsorption process.

Keywords: adsorption, biochar, nitrate, date stone

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Authors: Khadidja Hamida, Hayet Menasra, Hanane Rehali, Majda Charif, Rima Djezzar, Imane Akacha

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The BTO/PPW-Biochar composites were prepared with a simple technique to create a varying connection between semiconductor BTO (Bi₄Ti₃O₁₂) and biochar. This resulted in a product with strong optical properties for the removal of Rhodamine b dye (RhB). The BTO was created using Molten salt synthesis, while the biochar is sourced from potato plant waste (PPW), with one step of pyrolysis at 600 Cᵒ. The composites BTO/PPW-Biochar, with different ratio (30wt% and 50wt%) exhibited exceptional photocatalytic activity under sunlight irradiation. The efficiency of the photocatalytic performance is mainly influenced by the ratio of BTO/PPW-Biochar and the duration of exposure, with the biochar content having a significant impact on the performance. The characterization of BTO/PPW-Biochar with x=30wt%, 50wt%, were examined using scanning electron microscopy with energy -dispersive X-ray spectroscopy (SEM-EDX), Fourier-transform infrared spectroscopy (FTIR), and ultraviolet-visible (UV-Vis) analysis. The photochemical properties of the products were evaluated using UV-Vis absorption.

Keywords: BTO/PPW-Biochar composites, photocatalytic performance, adsorption, rhodamine b (RhB)

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Authors: Rasha A. Wheb

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This study aims to use artificial intelligence in recycling waste and using it to produce electricity instead of fuel, as we find that the relationship here is directly proportional, as the more the population density, commercial activity and other public facilities increase, the more they produce large quantities of household and institutional waste by residents or visitors, and this is what the capital suffers from. Baghdad has currently become very densely populated due to the migration of people from the countryside to the city for the population of Iraq, as it is a commercial center for Iraq and because of what some governorates have gone through in the past years of deteriorating security and regional terrorism, which made the capital a center for migration to be a safe place and to provide a livelihood, relative stability and sustainability, especially after the relative security situation improved from what it was in the past years, and because of the migration of residents of some neighboring and regional countries to Iraq and even non-neighboring countries due to what they suffer from wars, poverty and complete economic deterioration for some of those countries and because of the destruction of their infrastructure and the search for ways to live and a safe haven, which made Baghdad densely populated and crowded with people, as the capital is visited by many visitors from other governorates inside or outside the country, even if they do not settle. It is the first commercial center in Iraq, which results in environmental imbalance and distortion of the general view of the city, not to mention the health and psychological danger to individuals, due to the lack of modern technology in its service management sometimes, as it must be seriously reconsidered to improve its environmental and service situation, as it was the capital of the world and its present in the so-called golden age. The least that the capital deserves is to be one of the smart cities, and with this study we have developed strategies and a starting point at the beginning of the line to achieve sustainable development for it and improve living and other services; as well as intensifying the efforts of citizens and their participation among themselves in order to improve their environment; as the capital lacks the use of artificial intelligence in waste management and providing energy to fill the severe shortage, especially in the hot dry summer and cold rainy winter seasons. Failure to use a strategic waste recycling project causes waste to accumulate, but when it is recycled through the sorting feature, which is the basic stage and the first step in organizing waste management from home to the environment, it is considered a basic risk to produce a smart power plant.

Keywords: waste recycling, save energy, using AI, sustainable development

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Authors: Charif Majda, Menasra Hayet, Rehali Hanane, Khadidja Hamida, Loubna Sadaoui, Zineb Rais.

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Waste valorization signifies a paradigm shift in waste management, focusing on maximizing value while minimizing environmental impact. Photocatalysis represents a promising field of advanced scientific research with the potential to address pressing modern challenges. This distinct approach integrates the complementary effects of ultrasound and light, achieving unprecedented chemical process efficiency. This study explores the degradation of Rhodamine B in water solutions exposed to direct sunlight using sonophotocatalysis. The study utilizes a doped snail shell nanopowder as a source of calcium in the Aurivillius trilayer Bi₄Ti₃O₁₂, employing advanced biocatalysis, and a simulation catalysis doped with commercial CaCO₃ was used to compare the samples.A range of analytical techniques were employed to examine the samples, including X-ray diffraction, FT-IR, Raman, UV-visible spectroscopy, and BET. XRD diffraction revealed the orthorhombic structures for the two catalysts, with WCa/BTO exhibiting a larger crystallite size of 62.593 nm.The WCa/BTO samples demonstrated significant visible and UV-visible absorption, which is indicative of the formation of charge carriers. The combination of sonochemical and photocatalytic processes offers new opportunities to enhance photocatalytic efficiency and address environmental concerns. The study found that photocatalysis was completed in 30 minutes, while sonophotocatalysis produced hydroxyl radicals, thereby accelerating the degradation time by 50% with a pseudo-first-order reaction. The catalyst's second function is to eliminate microplastics, and the study's findings demonstrated that within 7 and 14 hours, the microplastics' surface structure, fractures, and functional groups changed, resulting in deformation and loosening. This contributes to the growing body of research on biodoped materials and their potential applications in environmental cleanup.

Keywords: bio-doped, ultrasound, photocatalysis, rhodamine-b, microplastic degradation

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Authors: Riya Koya

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Diabetes mellitus is a widely contracted condition characterized by unregulated glucose levels. This condition has a high prevalence, as 537 million adults were diagnosed with diabetes in 2021 (International Diabetes Federation, 2021. Diabetes is linked to various fatal long-term complications such as kidney disease and heart failure. Metformin (1,1-dimethyl biguanide hydrochloride) is a widely used pharmaceutical for treating diabetes by lowering blood glucose levels. Unfortunately, metformin has also been linked to adverse gastrointestinal effects, such as nausea, anorexia, constipation, etc. The severity of these gastrointestinal issues can lead to some Type II diabetics not being able to consume their prescribed metformin medication. The chemical mechanism of how metformin induces gastrointestinal issues is debated. However, it has been demonstrated that a weakening of the binding of the OCT1 protein (PDB identification: 8SC4) and metformin has been linked to increased gastrointestinal issues. In this study, molecular docking was performed on three metformin analogs with OCT1 to support which analog had the most robust binding to OCT1, thus also linked to reduced gastrointestinal issues. The analogs were also tested with AMPK (PDB identification: 2Y94) and compared against the binding scores of metformin with AMPK to support similar glucose-lowering properties. The analogs all included a guanidine functional group due to its connection to the glucose-lowering properties characteristic of metformin. This study utilized Chimera in conjunction with AutoDock Vina to perform the molecular docking studies, and Avogadro was used to visualize the metformin analogs. The binding scores and interactions provided by this software were recorded. Furthermore, all analogs’ interactions with the proteins were analyzed, including interactions with amino acid residues. One analog was found to have a binding score with OCT1 higher than that of metformin and a similar binding score to AMPK as that of metformin. This analog shows optimal scores for implementation as a glucose-lowering medication with lower gastrointestinal adverse effects.

Keywords: metformin, diabetes, molecular docking, gastrointestinal issues

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Authors: Kgomotso G. Mabena, Philiswa Nomngongo, Nomvano Mketo

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This study describes the synthesis and characterization of a magnetic cellulose gold nanocomposite (MCNC@Au) for vortex-assisted dispersive magnetic solid phase microextraction (VA-d-µ-mSPE) of organosulfur compounds (OSCs) in selected liquid fuel samples followed by high-pressure liquid chromatography (HPLC) analysis. The nanocomposite was synthesized utilizing an in-situ co-precipitation approach and characterization data from FTIR, P-XRD, TGA, TEM and SEM-EDX methods validated the formation of the desired nanocomposite. The most important parameters of the suggested VA-mSPE method were examined using the 2-level half-fractional factorial design and the central composite design in order to achieve high extraction efficiency. With pH as an insignificant parameter, the multivariate optimization results demonstrated that effective extraction was achieved when 20 mg of sorbent mass, 8 minutes of extraction time, and 20 mL sample volume were used. The acquired optimal condition will be used to assess the analytical performance of the VA-d-µ-mSPE technique. The quantitative parameters, including relative standard deviation (RSD), accuracy, precision, limit of quantification (LOQ), and limit of detection (LOD), will be determined. Additionally, real fuel oil samples, including crude oil, gasoline, diesel, and kerosene, will be subjected to the optimum and validated VA-d-µ-mSPE method in order to quantitatively determine various OSCs.

Keywords: MCNC@Au, VA-d-µ-mSPE, OSCs, HPLC.

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Authors: Giulia Di Prima, Cecilia La Mantia, Giada Tranchida, Giuseppe Angellotti, Bartolomeo Megna, Viviana De Caro

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Tooth extraction often leads to inflammation, microbial infection, and alveolar bone resorption, thus requiring a comprehensive therapeutic approach. At present, there are no standard reference therapeutic protocols following tooth extraction, but often an oral therapy with antibiotics is recommended. Resveratrol (RSV), a natural polyphenol known for its antioxidant, anti-inflammatory, and antimicrobial properties, could safely support tissue regeneration, but its clinical application is limited by its poor water solubility and low bioavailability following oral administration. Multicomponent lipid nanoparticles (mLNPs) can protect RSV, enhance its stability, and improve its interaction with the target tissue. Our previously developed mLNP-RSV nanosystem, composed of Labrasol® (liquid lipid), glyceryl monostearate (solid lipid), menthol and glycyrrhetinic acid (functional excipients) already displayed synergistic antioxidant effect and wound repair activity. Based on these preliminary results, the aim of this work was to propose an effective nano-based delivery system able to comprehensively improve the healing process after tooth extraction. To this scope hydroxyapatite (HXA), a well-known safe and bioabsorbable bone substitute, was combined with mLNP-RSV. The first issue addressed in this work was the choice of an appropriate hydrophilic matrix capable of allowing mLNP-RSV freeze-drying in order to obtain a solid nanocomposite suitable for post extraction socket insertion. Seven biocompatible polymers were then mixed in several weight ratios with the mLNP-RSV dispersion, subjected to freeze-drying, redispersed and evaluated by DLS analyses. SEM, XRD, FTIR, Raman spectroscopy and thermal analysis were used to extensively characterize and select the best nanocomposites. The latter were subjected to in vitro partitioning studies aimed at assessing their ability to release mLNP-RSV from the external hydrophilic matrix to lipophilic tissue. Finally, the optimal nanocomposite, mLNP-RSV-PEG10K, was combined with HXA to create a hybrid nanocomposite powder which was characterized in term of bulk properties to assess its suitability as a pharmaceutical intermediate to further produce the final mini-tablet dosage form. The latter was obtained by direct compression of the hybrid powder and resulted compliant with the post extraction socket cavity (≈59 mm³) and thus potentially useful to facilitate localized delivery, promote healing and mitigate alveolar volume reduction. This system could ensure wound asepsis, supports bone and soft tissue regeneration, and overcomes RSV’s pharmacokinetic limitations. By leveraging the combined properties of HXA and mLNP-RSV, the proposed hybrid nanocomposite mini-tablet represents an innovative therapeutic solution for effective and comprehensive post-extraction healing and will be thus further considered to both evaluate the formulation scalability and perform in vivo tests.

Keywords: hydroxyapatite, lipid nanoparticles, nanocomposite, resveratrol, wound healing

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Authors: Njabulo S. Mdlulia, Masixole Sihlahlaa, Vusimuzi Pakadea, Philiswa N Nomngongob, Nomvano Mketoa

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The removal of Ba, Na, Ni and V metals in crude oil, gasoline, diesel and kerosine was achieved by using Fe3O4@cellulose. The Fe3O4@cellulose was synthesized by using the co-precipitation method and was then characterized using the scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Brunauer-Emmentt-Teller (BET), zeta potential and Transmission electron microscopy (TEM). To obtain the optimum adsorption conditions, multivariate optimization tools such as a two-level full factorial and a central composite were used. The optimum conditions for the adsorptve removal of Ba, Na, Ni and V in the fuel oils were found to be 4.5, 1.5 M of HNO3, 40 minutes, 0.15 g and 0.15 g for pH, eluent concentration, extraction time, adsorbent mass and sample mass (model oil concentration). The adsorption method developed was very sensitive as it reported MLOD ranging from 0.022-1.51 µg/g while MLOQ ranged from 0.072-5.03 µg/g for metals under study. The optimum conditions were then applied to real fuel samples, which were crude oil, gasoline, kerosene and diesel.

Keywords: adsorption kinetics, F=fuel oils, isotherms, metals, thermodynamics

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Authors: Payam Hayati, Fateme Firoozbakht

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A novel photocatalytic adsorbent has been synthesized, comprising carbon dots (CD) embedded within a metal-organic framework (MOF) referred to as MIL-88B(Fe). This composite was prepared using a solvothermal technique, which is effective for producing advanced hybrid materials. The resulting CD@MIL-88B(Fe) was characterized through a variety of X-ray-based microscopic and spectroscopic methods, including electrochemical impedance spectroscopy, UV-Vis spectroscopy, Fourier-transform infrared spectroscopy (FT-IR), diffuse reflectance spectroscopy (DRS), thermogravimetric analysis (TGA), and photoluminescence (PL) analysis. The synthesized adsorbent exhibited remarkable photocatalytic activity in the removal of amphotericin B (AmB) and naproxen (Nap) from aqueous solutions under visible light irradiation, achieving removal efficiencies of up to 92% for AmB and 90% for Nap, with a relative standard deviation (RSD) of approximately 5%. The study also investigated various parameters influencing the degradation process of these pharmaceuticals. Optimal conditions were identified, including pH values of 3 for AmB and 4 for Nap, a catalyst concentration of 0.2 g. L⁻¹, and hydrogen peroxide concentrations ranging from 40 to 50 mM. Furthermore, reactive oxidative species such as hydroxyl radicals (·OH) and superoxide anions (·O₂) were detected through the use of various scavengers. Adsorption isotherm and kinetic studies revealed that the synthesized photocatalyst demonstrates dual functionality: it acts as an effective adsorbent with maximum adsorption capacities of 42.5 mg. g⁻¹ for AmB and 121.5 mg. g⁻¹ for Nap while also serving as a photocatalytic agent for the removal of these pharmaceutical contaminants.

Keywords: metal-organic frameworks, fenton-like degradation, CD@MIL-88B(Fe), Amphotericin B, Naproxen, heterogenous photocatalysts

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Authors: Roghaye Behroozi

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Traditional chemical synthesis methods for nanoparticles (NPs) often involve environmental hazards, complex procedures, and low yields. Green synthesis has emerged as a safer, cost-effective, and eco-friendly alternative. Citrus peel, an agricultural byproduct, provides a sustainable source of bioactive compounds capable of reducing and stabilizing metal ions, enabling the production of biocompatible NPs with valuable biomedical, photovoltaic, and environmental applications. This study aims to develop a green synthesis approach for producing metal oxide and silver nanoparticles (AgNPs) using citrus peel extracts, evaluating their antibacterial, antidiabetic, and photovoltaic properties. Nanoparticles were synthesized via aqueous citrus peel extracts, which served as natural reducing and capping agents. The synthesized NPs were characterized using techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-Vis spectroscopy to confirm their crystalline structure, morphology, and stability. Antibacterial efficacy was tested against common pathogenic bacteria, while antidiabetic activity was assessed through in vitro α-amylase inhibition. Photovoltaic properties were evaluated by incorporating the NPs into dye-sensitized solar cells (DSSCs). The synthesized NPs demonstrated distinct crystalline phases and spherical morphology, with notable stability and size uniformity. AgNPs showed significant antibacterial activity against tested pathogens, with enhanced inhibition at higher concentrations. In α-amylase inhibition assays, both metal oxide and AgNPs displayed dose-dependent antidiabetic potential. The DSSCs exhibited promising photovoltaic efficiency, confirming the feasibility of these NPs in light energy applications. Citrus peel-mediated synthesis of metal oxide and AgNPs provides a green, scalable method for producing nanoparticles with multifaceted applications. The findings highlight the potential of these NPs as eco-friendly agents in antibacterial and antidiabetic therapies and as components in renewable energy devices. This approach not only utilizes agricultural waste but also aligns with sustainable development goals by reducing synthetic chemical usage and environmental impact.

Keywords: antibacterial activity, citrus peel extract, green synthesis, metal oxide nanoparticles, silver nanoparticles

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Authors: Belhadj Fatma Zohra, Belhadj Ahmed Fouad, Chabaat Mohamed

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The properties of geotextiles can impact the long-term behavior of reinforced soils, which can lead to unexpected problems such as instability and excessive deformation. Research into the material’s rheological properties and nonlinear behavior is required to overcome this issue. This study focuses on six isotropic hyperelastic models (Neo-Hooke, Mooney-Rivlin, Ogden, Yeoh, Arruda-Boyce, and Van der Waals) commonly used to describe the behavior of PET woven geotextiles in civil engineering applications. The models are adjusted for uniaxial tension testing in the warp and weft directions based on experimental data; the Yeoh and Neo-Hooke models accurately predict the behavior of these geotextiles. The study aims to enhance an understanding of how geotextiles behave under varying loads through testing and finite element simulations. The strong correlation between experimental and simulation results can help develop hyperelastic material models for geotextiles. This framework can be beneficial for manufacturers and engineers in addressing soil-structure interaction concerns effectively in their projects.

Keywords: soil-structure interaction interface, geotextiles rheological characteristics, hyperelastic models, uniaxial tension testing, FEA modeling

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Authors: I.K.Bedaida, A.Reguig

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Propolis is a complex resinous hive product, collected by bees from plants sources. Its chemical and constituents composition depends on its floral origin, and varies according to climatic and geographical conditions. Its strong antibacterial activity was correlated to the highest concentration of phenols. Staphylococcus aureus is the most significant human pathogen often carried asymptomatically on the bodies of both humans and animals, and has been implicated as causing severe morbidity and mortality worldwide. S. aureus has the ability to produce several exoenzymes that contribute to virulence such as coagulase, hemolysin, protease, and lipase and enterotoxin. It is considered also as one of the most important food safety concerns for the food industry. The aim of the study was to analyze propolis extracts' phytochemical and to study the cytoplasmic membrane damage of crude ethanol extract of propolis against Staphylococcus aureus ATCC 25923 by observing the changes of cell microstructure using scanning electron microscope and cell permeability damages. Propolis Ethanolic extract was analyzed by ultra-high-performance liquid chromatography coupled with a diode array detector and an electrospray mass spectrometer (UHPLC-DAD-ESI/MS). Additionally, polyphenols and volatile compounds of EEP was analyzed by gas chromatography–mass spectrometry GC-MS. Staphylococcus aureus ATCC 25923 was subjected to agar dilution method to determine the minimum inhibitory concentration (MIC) and potassium and protein leakages were performed to detect permeability damages. The results showed that the minimum inhibitory concentration (MIC) of EEP against Staphylococcus aureus ATCC 25923 was 39 µg/ml. Adding EEP at MIC level, there were obvious changes in the morphology of bacteria cells indicating cell damage. When EEP were added at (2MIC) levels, the cells were destroyed. EEP cause rapid increase the concentration of proteins and potassium in cell suspension.

Keywords: antimicrobial, GC-MS, HPLC, propolis, time kill effect

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Authors: Varshith Kotagiri, Lei Li

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Fluorescent sensors are organic fluorophores that detect specific analytes with quantitative fluorescence intensity changes. They have offered impressive benefits compared with instrumental techniques, such as low cost, high selectivity, and rapid responses. One issue that limits the fluorescent sensors for further application is their poor solubility in the aqueous medium, where most targeted analytes, including metal ions, inorganic anions, and neutral biomolecules, are readily soluble. When fluorescent sensors are utilized to detect these analytes, a heterogeneous phase is formed. In most cases, an extra water-miscible organic solvent is needed as an additive to facilitate the sensing process, which complicates the measurement operations and produces more organic waste. We aim to resolve this issue by skillful molecular design to introduce a hydrophilic side chain to the fluorescent sensor, increasing its water solubility and facilitating its sensing process to analytes, like various protons, fluoride ions, and copper ions, in an aqueous medium. Simultaneously, its sensitivity and selectivity will be retained. This work will simplify the sensing operations and reduce the amount of organic waste produced during the measurement. This strategy will additionally be of broad interest to the chemistry community, as it introduces the idea of modifying the molecular structure to apply an initial hydrophobic compound under hydrophilic conditions in a feasible way.

Keywords: organic fluorescent sensor, analytes, sensing, aqueous medium, phenanthroimidazole, hydrophilic side chain

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Authors: Tanghourte Mohamed, Ouassou Nazih, El Mesky Mohammed, Znini Mohamed, Mabrouk El Houssine

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In the present study, a distinct organic inhibitor, namely 2,2'-(piperazine-1,4-diyl)bis(N-(4-bromophenyl)acetamide) (PBRA), was synthesized and characterized using ¹H, ¹³C NMR, and IR spectroscopy. Subsequently, the inhibition effect of PBRA on the corrosion of carbon steel in 1 M HCl was studied using electrochemical measurements such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The results showed that the inhibition efficiency increased with concentration, reaching 87% at 10-³M. Furthermore, PBRA remained effective at temperatures ranging from 298 to 328 K. The adsorption of the inhibitor onto carbon steel was well described by the Langmuir adsorption isotherm. Additionally, a correlation between the molecular structure and quantum chemistry indices was established using density functional theory (DFT).

Keywords: synthesis, corrosion, inhibition, piperazine, efficacy, isotherm, acetamide

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Authors: Hammadi Larbi

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The major problem with oil-based drilling muds (reverse emulsions) is their thermodynamic instability and their high tendency to coalescence over time, irreversibly leading to destabilization. Water/Oil reverse emulsion drilling Muds are highly recommended when significant depths are reached. This study aimed to contribute experimentally to the knowledge of the structure (stability) and rheological behavior of drilling mud systems based on water/crude oil inverse emulsions through the investigation of the effect of organophilic clay. The chemical composition of organophilic clay such as VG69 shows a strong presence of silicon oxide (SiO2), followed by aluminum oxide (Al2O3), so these two elements are considered to be the main constituents of organophilic clays. The study also shows that the SiO2/Al2O3 ratio is equal to 3.52, which can be explained by the high content of free silica contained in the organophile clay used. The particle size analysis of the organophilic clays showed that the size of the of the particles analysed is in the range of 30 to 80 μm, this result ensures the correct particle size quality of organophilic clays and allows these powders to be used in Drilling mud systems.The experimental data of steady-state flow measurements are analyzed in the classic way by the Herschel-Bulkley model. Microscopic observation shows that the addition of quantities of organophilic clay type VG69 less than or equal to 3 g leading to the stability of the water/oil inverse emulsions, on the other hand, for quantities greater than 3 g, the emulsions are destabilized. The results obtained also showed that adding 3 g of organophilic clay to the crude oil drilling mud improves their stability by 70%.

Keywords: drilling muds, inverse emulsions, rheological behavior, yield stress, stability, organophilic clay

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Authors: Anna Pajdak, Mateusz Kudasik, Aleksandra Gajda, Katarzyna Kozieł

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Shales are a type of fine-grained sedimentary rocks, which are composed of small grains of several to several dozen μm in size and consist of a variable mixture of clay minerals, quartz, feldspars, carbonates, sulphides, amorphous material and organic matter. The study involved an analysis of the basic physical properties of shale rocks from several research wells in Poland. The structural, sorption and seepage parameters of these rocks were determined. The total porosity of granular rock samples reached several percent, including the share of closed pores up to half a percent. The volume and distribution of pores, which are of significant importance in the context of the mechanisms of methane binding to the rock matrix and methods of stimulating its desorption and the possibility of CO₂ storage, were determined. The BET surface area of the samples ranged from a few to a dozen or so m²/g, and the share of micropores was dominant. In order to determine the interaction of rocks with gases, the sorption capacity in relation to CO₂ and CH₄ was determined at a pressure of 0-1.4 MPa. Sorption capacities, sorption isotherms and diffusion coefficients were also determined. Studies of competitive sorption of CO₂/CH₄ on shales showed a preference for CO₂ sorption over CH₄, and the selectivity of CO₂/CH₄ sorption decreased with increasing pressure. In addition to the pore structure, the adsorption capacity of gases in shale rocks is significantly influenced by the carbon content in their organic matter. The sorbed gas can constitute from 20% to 80% of the total gas contained in the shales. With the increasing depth of shale gas occurrence, the share of free gas to sorbed gas increases, among others, due to the increase in temperature and surrounding pressure. Determining the share of free gas to sorbed gas in shale, depending on the depth of its deposition, is one of the key elements of recognizing the gas/sorption exchange processes of CO₂/CH₄, which are the basis of CO₂-ESGR technology. The main objective of the work was to identify the correlation between different forms of gas occurrence in rocks and the parameters describing the pore space of shales.

Keywords: shale, CH₄, CO₂, shale gas, CO₂ -ESGR, pores structure

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Authors: M. S. Yalfani, J. Kohzadi, P. Ghadimi, S. Sobhani, M. Ghadimi

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The use of oil and water-soluble corrosion inhibitors has been established in Iranian oil and gas production systems for a long time. Imidazoline and its derivatives are being extensively used which are known as conventional corrosion inhibitors. This type of products has shown significant performance and low side effects, so that could monopolize the market of inhibitors in this region. However, the price growth of imidazolines as well as the development of new lower cost components with similar or even higher performance than imidazoline, have influenced the exclusive market of imidazoline based products. During the latest years, pyridine and its derivatives have challenged imidazoline due to their remarkable anticorrosive properties and lower price as well. Recently, we could present a formulated water soluble inhibitor based on pyridine - an alkyl pyridine quaternary salt (APQS) - which could successfully pass all lab tests and eventually succeeded to be applied in an offshore sweet oil pipeline. The product was able to achieve high corrosion protection (> 90 %) with LPR technique at low dosages of 15-25 ppm under severe corrosion conditions. Moreover, the lab test results showed that the APQS molecule is able to form a strong and persistent bond with the metal surface. The product was later nominated to be evaluated through a field trial in an offshore sweet oil pipeline where PH2S < 0.05 psi and CO₂ is 6.4 mol%. The three months trial -extended to six months- resulted in remarkable internal protection obtained by continuous injection of 10 ppm inhibitor, which was as low as 1 mpy measured by both weight loss corrosion coupons and online ER probes. In addition, no side effects such as tight emulsion and stable foaming, were observed. The residual of corrosion inhibitor was measured at the end of pipeline to assure the full coverage of the inhibitor throughout the pipeline. Eventually, these promising results were able to convince the end user to consider pyridine based inhibitor as a reliable alternative for imidazoline.

Keywords: corrosion inhibitor, pyridine, sweet oil, pipeline, offshore

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Authors: Adam Wiryawan

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The levels of micro metal elements in the soil are influenced by soil management. In this research, the influence of soil management on the content of micro metal elements in the soil in the UB forest was studied. The metals studied include Zn, Mn, Cu, Fe, Cd, and Pb. Soil samples were taken from five sampling points on soil in the UB forest, both soils tilled and untilled. Before analysis, soil samples were digested with HNO₃ solution, and metal levels in soil samples were measured using atomic absorption spectrometry (AAS). The results of the analysis of metal content in the soil at the UB forest show that tilled land has consistently lower levels of metals like Zn, Mn, Cu, and Fe compared to untilled land. Meanwhile, Pb and Cd metals were not detected in all soil samples.

Keywords: soil treatment, metal content, forest soil, Malang District

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Authors: Wei Jin

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Efficient and selective metal recovery from emerging solid waste, such as spent lithium batteries, electronic waste and SCR catalysts, is of great importance from both environmental and resource considerations. In order to overcome the bottlenecks of long flow-sheet and severe secondary pollution in conventional processes, the rational design of 2-electron oxygen reduction reaction (ORR) and capacitive deionization (CDI) nanomaterials were developed for the precise electrochemical metal recovery. It has been demonstrated that the modified carbon nanomaterials can be employed as 2e ORR to produce H2O2 in aqueous solution, in which the metal can be leached out from the solid waste as ions. Moreover, the multi-component metallic solution can be electrochemically extracted with good efficiency and selectivity with the nanoporous aerogel. Each system presents stable performance for long-term operation and can be used in industrial solid waste treatment. This study provides a materials-oriented, cleaner metal recovery approach for strategic metal resources sustainability.

Keywords: electrochemistry, metal recovery, waste steams, nanomaterials

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Authors: Abdullahi Jibril, Rod Burgass, Antonin Chapoy

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Carbon dioxide (CO₂) is widely used in reservoirs to enhance oil and gas production, mixing with natural gas and other impurities in the process. However, hydrate formation frequently hinders the efficiency of CO₂-based enhanced oil recovery, causing pipeline blockages and pressure build-ups. Current hydrate prediction methods are primarily designed for gas mixtures with low CO₂ content and struggle to accurately predict hydrate formation in CO₂-rich streams in equilibrium with salt solutions. Given that oil and gas reservoirs are saline, experimental data for CO₂-rich streams in equilibrium with salt solutions are essential to improve these predictive models. This study investigates the inhibition of hydrate formation in a CO₂-rich gas mixture (CO₂, CH₄, N₂, H₂ at 84.73/15/0.19/0.08 mol.%) using multicomponent salt solutions at concentrations of 2.4 wt.%, 13.65 wt.%, and 27.3 wt.%. The setup, test fluids, methodology, and results for hydrates formed in equilibrium with varying salt solution concentrations are presented. Measurements were conducted using an isochoric pressure-search method at pressures up to 45 MPa. Experimental data were compared with predictions from a thermodynamic model based on the Cubic-Plus-Association equation of state (EoS), while hydrate-forming conditions were modeled using the van der Waals and Platteeuw solid solution theory. Water activity was evaluated based on hydrate suppression temperature to assess consistency in the inhibited systems. Results indicate that hydrate stability is significantly influenced by inhibitor concentration, offering valuable guidelines for the design and operation of pipeline systems involved in offshore gas transport of CO₂-rich streams.

Keywords: CO₂-rich streams, hydrates, monoethylene glycol, phase equilibria

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Authors: Letemariam Gebreslassie Gebrekidan

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Water pollution is one of the most feared problems in modern societies, especially in developing countries like Ethiopia. Nanoparticles with controlled size and composition are of fundamental and technological interest as they provide solutions to technological and environmental challenges in the areas of solar energy conversion, catalysis, medicine, and water treatment. The synthesis of metallic nanoparticles is an active area of academic and, more importantly, application research in nanotechnology. Adsorption is a process in which pollutants are absorbed on a solid surface. A molecule (pollutant) adhered to the solid surface is called an adsorbate, and the solid surface is an adsorbent. Adsorption is controlled by various parameters such as temperature, the nature of the adsorbate and adsorbent, and the presence of other pollutants along with the experimental conditions (pH, concentration of pollutants, contact time, particle size, and temperature). Depending on the main problem of water pollution, this research is available on the adsorption of wastewater using silver nanoparticles extracted from phytolacca Dodecandra leaf. AgNP was synthesized from a 1mM aqueous solution of silver nitrate (AgNO3) and Phytolacca Dodecandra leaf extract at room temperature. The synthesized nanoparticles were characterized using UV/visible Spectrometer, FTIR and XRD. In the UV-Vis spectrum, The Surface Plasmon resonance (SPR) peak was observed at 414 nm, which confirmed the synthesis of AgNPs. FTIR spectroscopy, recorded from 4000 cm-1 to 400 cm-1, indicated the presence of a capping agent with the nanoparticles. From the XRD results, the average crystalline size was estimated to be 20 nm Confirming the nanoparticle nature of the obtained sample. Thus, the present method leads to the formation of silver nanoparticles with well-defined dimensions. The effects of different parameters like solution pH, adsorbent dose, contact time and initial concentration of dye were studied. The concentration of MB is 0.01 mg/L and 0.002 mg/L before and after adsorption, respectively. The wastewater containing MB was well purified using AgNP adsorbent.

Keywords: wastewater, silver nanoparticle, Characterization, adsorption, parameter

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Authors: Muddser Ghaffar

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In material science, synthetic chiral polymers are becoming increasingly significant due to their distinct properties that distinguish them from other polymer materials. One special technique for producing well-defined chiral polymers is asymmetric kinetic resolution polymerization (AKRP), which adds stereo regularity to a polymer chain by the kinetic resolution of a race mate preferentially polymerizing one enantiomer. Apart from making it possible to characterize chiral polymers enantioselective, AKRP can synthesize chiral polymers with high stereo selectivity. This review includes the literature on the use of enzymes, chiral metal complexes, and organ catalysts as AKRP promoters. One enantiomer reacts more quickly than the other in this kind of polymerisation, quickly entering the expanding polymer chain, while the kinetically less reactive enantiomer stays unreactive and is readily separated using straightforward purification techniques. The degree of chiral induction and overall chirality of the chiral polymers that are generated may be assessed using the enantiomeric excess (ee) of the initial monomer, which is frequently determined by chiral HPLC analysis, throughout the polymerisation process.

Keywords: stereo regularity, polymers, dynamical, symmetric

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Authors: Mulugeta Gurum Gerechal

Abstract:

Nowadays, the photocatalytic mechanism of water purification using nanoparticles has gained wider acceptance. For this purpose, the crystal form of N- TiO₂ and Ag-TiO₂ was prepared from TiCl₄, urea, NH₄OH, and AgNO₃ by sol-gel method and simple solid phase reaction followed by calcination at a temperature of 400°C for 4h at each. The synthesized photocatalysts were characterized using XRD, SEM, and UV-visible diffuse reflectance spectra. In the experiment, it was found that the absorption edge of N-TiO₂ was an efficient shift to visible light as compared to Ag-TiO₂. The XRD diffraction makes the particle size of N-TiO₂ smaller than Ag-TiO₂. The effect of catalyst loading and the effect of temperature on the photocatalytic efficiency of the prepared samples was tested using methylene blue as a target pollutant. The photocatalytic degradation efficiency of the catalysts for methylene blue was increased from 57.05 to 96.02% under solar radiation as the amount of the catalyst increased from 0.15 to 0.45 gram for N-TiO₂. Similarly, photocatalytic degradation of methylene blue was increased from 40.32 to 81.21% as the amount of Ag-TiO₂ increased from 0.05g to 0.1g. In addition, the photocatalytic degradation efficiency of the catalysts for the removal of methylene blue was increased from 58.00 to 98.00 and 47.00 to 81.21% under solar radiation as the calcination temperature of the catalyst increased from 300 to 500 for N-TiO₂ for Ag-TiO₂ 300 to 400⁰C. However, a further increase in catalyst loading and calcination temperature was found to decrease the degradation efficiency.

Keywords: photocatalysis, degradation, nanoparticles, catalyst loading, calcination, methylene blue

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Authors: Y. B. Idris, M. Sirajo, L. G. Hassan, T. Izuagie, T. Muktar, I. Lawal, A. U. Abubakar

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This study investigates the extraction, phytochemical composition, and antimicrobial activity of bioactive compounds from red millipedes using three different solvents: n-Hexane, Chloroform, and Methanol. The largest yield was obtained from the methanol extract, which had percentage yields of 0.8%, 2.2%, and 5.6%, respectively. Terpenoids and sterols were found in all extracts according to preliminary zoochemical screening, but only the methanol extract included saponins and phenols. With a maximum zone of inhibition of 9 mm at 1000 µg/ml, antimicrobial susceptibility tests revealed that the methanol extract had the strongest antibacterial activity, especially against Escherichia coli and Staphylococcus aureus. Significant activity was also shown by the n-hexane extract, although the chloroform extract had only mild antibacterial activity. Tests for minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) verified that the methanol extract was more effective than the other extracts, particularly against S. aureus and S. typhi. None of the extracts, nonetheless, showed any discernible antifungal action. The potential of red millipede extracts, especially those based on methanol, as a source of antimicrobial chemicals for use in the future is highlighted by this work.

Keywords: millipedes, defensive extraction, antibacterial, antifungal, antimicrobial, minimum inhibitory concentration (MIC), minimum bacterial concentration (MBC)

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