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The presence of Ag(I) and Pb(II) ions in wastewater poses a significant threat to human health in contemporary times. This study aims to explore the development of a novel and economical adsorbent by grafting MnO2 particles onto low-rank coal, providing an innovative solution for the remediation of water contaminated with silver and lead. The synthesized nanocomposites, referred to as MnO2-Coal, underwent thorough characterization using FTIR, XRD, BET, and SEM to highlight the feasibility of in-situ surface modification of coal with MnO2 nanoparticles. The adsorption of Ag(I) and Pb(II) from their respective aqueous solution onto MnO2-Coal was systematically investigated, with optimization of key parameters such as pH, temperature, initial concentration, contact time, ionic strength, and competing ions. Remarkably adsorption equilibrium was achieved within a 10 min, resulting in impressive removal rates of 80-90 % for both Ag(I) and Pb(II) at pH 6. The experimental data were evaluated using Langmuir, Freundlich, and Temkin isotherm models. The Langmuir isotherm model proved to be more accurate in representing the adsorption of Ag(I) and Pb(II) ions onto MnO2-Coal, exhibiting high regression coefficients (R2 = 0.99) and maximum adsorption capacities of 93.57 and 61.98 mg/g, along with partition coefficients of 4.53 and 71.92 L/g for Ag(I) and Pb(II), respectively, at 293 K. Kinetic assessments employing PFO, PSO, Elovich, and IPD models indicated that the PFO and PSO models were most suitable for adsorption mechanism of Pb(II) and Ag(I) on MnO2-Coal composites, respectively. Moreover, thermodynamic evaluation revealed the spontaneous and endothermic adsorption process for Ag(I), while exothermic behavior for adsorption of Pb(II). Importantly, this approach not only demonstrates cost-effectiveness but also environmental friendliness in treating heavy metal-contamination in water. The research suggests the potential of MnO2-Coal composites as efficient and sustainable adsorbents for water purification applications.
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Plomo , Compuestos de Manganeso , Óxidos , Plata , Aguas Residuales , Contaminantes Químicos del Agua , Plata/química , Plomo/química , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Adsorción , Compuestos de Manganeso/química , Óxidos/química , Carbón Mineral , Purificación del Agua/métodos , Concentración de Iones de Hidrógeno , CinéticaRESUMEN
Flexible capacitive energy storage applications require polymer nanocomposites with high dielectric properties, which can be accomplished by addition of inorganic nanofillers to the polymer matrix. Low-density polyethylene (LDPE), known for its good dielectric characteristics and wide use in electrical insulation have been investigated for the desired applications. However, the improvement of its breakdown strength still continues with the use of various nanomaterials employed as nanofillers. In this study, a waste-derived material known as biomass fly ash (BFA) as a nanofiller to improve the dielectric properties of LDPE has been explored. BFA exhibits versatility in its composition with various metal oxides, making it an attractive choice as a nanofiller. The BFA-LDPE sheets were prepared using a conventional solvent mixing and subsequent hot-pressing process, incorporating BFA loadings ranging from 1 % to 4 wt%. The effects of different BFA loadings were carefully examined, and the synthesized nanocomposites were extensively characterized using various characterization methods, such as XRD, SEM, FTIR, TGA and dielectric constant measurements, to investigate the crystallographic properties, morphology, chemical composition, and thermal stability. Among all the nanocomposites, 4 wt%BFA-LDPE exhibited the highest dielectric constant, with a value of 11.58, compared to simple LDPE that had a dielectric constant of 8.33. This improvement is ascribed to the synergistic effects of different inorganic metal oxides (SiO2, MgO, and Fe2O3) present in BFA. The results showed a significant enhancement in dielectric properties, indicating that the waste-derived BFA can be purposefully applied as an effective nanofiller in the LDPE-based composites with even less than 4% loading for electrical insulating applications in future studies.
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Introduction Lower limb fractures frequently require immobilization with backslabs to promote healing. This study investigates a novel approach involving the incorporation of a single ridge to enhance backslab strength while maintaining cost-effectiveness. Objective The aim of this study was to assess the mechanical performance of ridged backslabs in comparison to traditional non-ridged backslabs, specifically focusing on their load-bearing capacity and cost-effectiveness when used in lower limb fractures. Methods This experimental study, conducted between January 2023 and June 2023, compares three groups of backslabs with varying layers (eight, ten, and twelve) that were fabricated, each consisting of four ridged and four non-ridged specimens. These backslabs, constructed from six-inch plaster of Paris rolls, were 190 cm in length. A three-point bending test was conducted on both groups using a Hounsfield H100KS Universal Testing Machine (Tinius Olsen Ltd., Redhill, UK), with a crosshead speed of 5 mm/min and a span distance of 190 mm between supports. Results Significant differences in mean maximum force endured were observed between the ten-layered and twelve-layered flat and ridged backslabs (p-values: 0.003 and 0.004, respectively). Ten-layered ridged backslabs exhibited a 56 N higher load-bearing capacity, while twelve-layered ridged backslabs withstood 73.9 N more force than their flat counterparts, underscoring the superior strength of ridged lower limb backslabs. Conclusion Ridged backslabs outperformed non-ridged backslabs in terms of strength when subjected to external forces. These findings support the potential adoption of ridged backslabs as a lightweight, cost-effective, and robust alternative for immobilization in lower limb fractures.
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Toxic fission products, such as cesium (137Cs) and iodine (129I) are of great concern because of their long half-lives and high solubility in water. The simultaneous removal of Cs and I using a single adsorbent is an area of increasing interest. In this study, MXene/silver nanowire (AgNW) composite was synthesized through physical mixing and employed for simultaneous removal of iodide (I-) and cesium (Cs+) ions from contaminated water. The MXene/AgNW composite demonstrated excellent adsorption capacities of 84.70 and 26.22 mg/g for I- and Cs+, respectively. The experimental data supported the hypothesis of multilayer adsorption of Cs+ owing to the inter-lamellar structures and the presence of heterogeneous adsorption sites in MXene. The interaction between I- and the AgNW involved chemisorption followed by monolayer adsorption. MXene/AgNW composite material exhibited promising results in the presence of competitive ions under extreme pH conditions. Thus, synthesized composite materials holds promising potential as an adsorbent for the remediation of radioactive liquid waste.
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Metal sulfides and 2D materials are the propitious candidates for numerous electrochemical applications, due to their superior conductivity and ample active sites. Herein, CuS nanoparticles were fabricated on 2D greener HF-free Cl-terminated MXene (Ti3C2Cl2) sheets by the hydrothermal process as a proficient electrocatalyst for the hydrogen evolution reaction (HER) and overall water splitting. CuS/Ti3C2Cl2 showed an overpotential of 163 mV and a Tafel slope of 77 mV dec-1 at 10 mA cm-2 for the HER. In the case of the OER, CuS/Ti3C2Cl2 exhibited an overpotential of 334 mV at 50 mA cm-2 and a Tafel slope of 42 mV dec-1. Moreover, the assembled CuS/Ti3C2Cl2||CuS/Ti3C2Cl2 electrolyzer delivered current density of 20 mA cm-2 at 1.87 V for overall water splitting. The CuS/Ti3C2Cl2 electrocatalyst showed excellent stability to retain 96% of its initial value for about 48 hours at 100 mA cm-2 current density. The synthesis of CuS/Ti3C2Cl2 enriches the applications of MXene/metal sulfides in efficient bifunctional electrocatalysis for alkaline water splitting.
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The goal of this research is to investigate the effects of Ohmic heating, heat generation, and viscous dissipative flow on magneto (MHD) boundary-layer heat transmission flowing of Jeffrey nanofluid across a stretchable surface using the Koo-Kleinstreuer-Li (KKL) model. Engine oil serves as the primary fluid and is suspended with copper oxide nanomolecules. The governing equations that regulate the flowing and heat transmission fields are partial-differential equations (PDEs) that are then converted to a model of non-linear ordinary differential equations (ODEs) via similarity transformation. The resultant ODEs are numerically resolved using a Keller box technique via MATLAB software that is suggested. Diagrams and tables are used to express the effects of various normal liquids, nanomolecule sizes, magneto parameters, Prandtl, Deborah, and Eckert numbers on the velocity field and temperature field. The outcomes display that the copper oxide-engine oil nanofluid has a lower velocity, drag force, and Nusselt number than the plain liquid, although the introduction of nanoparticles raises the heat. The heat transference rate is reduced by Eckert number, size of nanomolecules, and magneto parameter rising. Whilst, Deborah number is shown to enhance both the drag-force factor and the heat transfer rate. Furthermore, the discoveries reported are advantageous to upgrading incandescent lighting bulbs, heating, and cooling equipment, filament-generating light, energy generation, multiple heating devices, and other similar devices.
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The identification of the target molecule is required for rapid and reliable clinical diagnosis and disease monitoring [...].
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Técnicas Biosensibles , NanoestructurasRESUMEN
The outbreak of the COVID-19 pandemic has also triggered a tsunami of news, instructions, and precautionary measures related to the disease on social media platforms. Despite the considerable support on social media, a large number of fake propaganda and conspiracies are also circulated. People also reacted to COVID-19 vaccination on social media and expressed their opinions, perceptions, and conceptions. The present research work aims to explore the opinion dynamics of the general public about COVID-19 vaccination to help the administration authorities to devise policies to increase vaccination acceptance. For this purpose, a framework is proposed to perform sentiment analysis of COVID-19 vaccination-related tweets. The influence of term frequency-inverse document frequency, bag of words (BoW), Word2Vec, and combination of TF-IDF and BoW are explored with classifiers including random forest, gradient boosting machine, extra tree classifier (ETC), logistic regression, Naïve Bayes, stochastic gradient descent, multilayer perceptron, convolutional neural network (CNN), bidirectional encoder representations from transformers (BERT), long short-term memory (LSTM), and recurrent neural network (RNN). Results reveal that ETC outperforms using BoW with a 92% of accuracy and is the most suitable approach for sentiment analysis of COVID-19-related tweets. Opinion dynamics show that sentiments in favor of vaccination have increased over time.
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Devastating citrus disease Huanglongbing (HLB) is without existing cures. Herein, we present results demonstrating the possible mechanisms (hypoxia stress) behind HLB-triggered shoot dieback by comparing the transcriptomes, hormone profiles, and key enzyme activities in buds of severely and mildly symptomatic 'Hamlin' sweet orange (Citrus sinensis). Within six months (October - May) in field conditions, severe trees had 23% bud dieback, greater than mild trees (11%), with a concomitant reduction in canopy density. In February, differentially expressed genes (DEGs) associated with responses to osmotic stress, low oxygen levels, and cell death were upregulated, with those for photosynthesis and cell cycle downregulated in severe versus mild trees. For severe trees, not only were the key markers for hypoxia, including anaerobic fermentation, reactive oxygen species (ROS) production, and lipid oxidation, transcriptionally upregulated, but also alcohol dehydrogenase activity was significantly greater compared to mild trees, indicating a link between bud dieback and hypoxia. Tricarboxylic acid cycle revival, given the upregulation of glutamate dehydrogenase and alanine aminotransferase DEGs, suggests that ROS may also be generated during hypoxia-reoxygenation. Greater (hormonal) ratios of abscisic acid to cytokinins and jasmonates and upregulated DEGs encoding NADPH oxidases in severe versus mild trees indicate additional ROS production under limited oxygen availability due to stomata closure. Altogether, our results provided evidence that as HLB progresses, excessive ROS produced in response to hypoxia and during hypoxia-reoxygenation likely intensify the oxidative stress in buds leading to cell death, contributing to marked bud and shoot dieback and decline of the severely symptomatic sweet orange trees.
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This work elaborates on the decoration of metal oxides (ZnO and Fe3O4) between MXene sheets for use as the supporting geometry of PCBM electron transport layers (ETLs) in perovskite solar cells and X-ray detectors. The metal oxide supports for carrying the plentiful charge carriers and the hydrophobic nature of MXenes provide an easy charge transfer path through their flakes and a smooth surface for the ETL. The developed interface engineering based on the MXene/ZnO and MXene/Fe3O4 hybrid ETL results in improved power conversion efficiencies (PCEs) of 13.31% and 13.79%, respectively. The observed PCE is improved to 25.80% and 30.34% by blending the MXene/ZnO and MXene/Fe3O4 nanoparticles with the PCBM layer, respectively. Various factors, such as surface modification, swift interfacial interaction, roughness decrement, and charge transport improvement, are strongly influenced to improve the device performance. Moreover, X-ray detectors with the MXene/Fe3O4-modulated PCBM ETL achieve a CCD-DCD, sensitivity, mobility, and trap density of 15.46 µA cm-2, 4.63 mA per Gy per cm2, 5.21 × 10-4 cm2 V-1 s-1, and 1.47 × 1015 cm2 V-1 s-1, respectively. Metal oxide-decorated MXene sheets incorporating the PCBM ETL are a significant route for improving the photoactive species generation, long-term stability, and high mobility of perovskite-based devices.
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INTRODUCTION: The COVID-19 pandemic has led to drastic measures being implemented for the management of surgical patients across all health services worldwide, including the National Health Service in the United Kingdom. It is suspected that the virus has had a detrimental effect on perioperative morbidity and mortality. Therefore, the aim of this study was to assess the impact of the COVID-19 pandemic on these outcomes in emergency general surgical patients. METHODS: Emergency general surgical admissions were included in this retrospective cohort study in one of the COVID-19 hotspots in the South East of England. The primary outcome was the 30-day mortality rate. Secondary outcomes included the length of stay in hospital, complication rate and severity grade and admission rates to the ITU. RESULTS: Of 123 patients, COVID-19 was detected in 12.2%. Testing was not carried out in 26%. When comparing COVID-positive to COVID-negative patients, the mean age was 71.8 + 8.8 vs. 50.7 + 5.7, respectively, and female patients accounted for 40.0 vs. 52.6%. The 30-day mortality rate was 26.7 vs. 3.9 (OR 6.49, p = 0.02), respectively. The length of stay in hospital was 20.5 + 22.2 vs. 7.7 + 9.8 (p < 0.01), the rate of complications was 80.0 vs. 23.7 (OR 12.9, p < 0.01), and the rate of admission to the ITU was 33.3 vs. 7.9% (OR 5.83, p = 0.01). CONCLUSION: This study demonstrates the detrimental effect of COVID-19 on emergency general surgery, with significantly worsened surgical outcomes.
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COVID-19 , Humanos , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Estudios Retrospectivos , Pandemias , Medicina Estatal , HospitalizaciónRESUMEN
Yogurt is defined as a coagulated milk product obtained from the fermentation of lactose into lactic acid. Drinking yogurt (laban) was prepared from buffalo milk, cow milk, and a 50:50 blend (cow + buffalo milks) by adding 0.5% carboxymethyl cellulose to each of the 3 milk treatments. Samples were then refrigerated for 7, 14, and 21 d before determination of physical, microbial, and sensory parameters. Yogurt prepared from buffalo milk had higher fat and protein contents, and better taste, aroma, and overall consumer acceptability compared with laban prepared from cow milk or mixed milk. During storage, protein and total solids contents remained unchanged, whereas milk fat, color, appearance, taste, smell, texture, and overall acceptability of laban decreased in the different treatment groups. The acidity of laban increased with storage time. Bacteria, including coliforms, were not found in any treatment group during storage. In conclusion, overall acceptability of laban prepared from buffalo milk was higher than that made from cow milk or mixed milk, but increased storage time reduced the quality of laban prepared from cow, buffalo, or mixed milk.
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Búfalos , Yogur , Femenino , Bovinos , Animales , Yogur/microbiología , Ácidos Grasos/análisis , Leche/química , Fermentación , GustoRESUMEN
In view of ever-increasing environmental pollution, there is an immediate requirement to promote cheap, multiplexed, sensitive and fast biosensing systems to monitor these pollutants or contaminants. Aptamers have shown numerous advantages in being used as molecular recognition elements in various biosensing devices. Graphene and graphene-based materials/nanohybrids combined with several detection methods exhibit great potential owing to their exceptional optical, electronic and physicochemical properties which can be employed extensively to monitor environmental contaminants. For environmental monitoring applications, aptamers have been successfully combined with graphene-based nanohybrids to produce a wide range of innovative methodologies. Aptamers are immobilized at the surface of graphene based nanohybrids via covalent and non-covalent strategies. This review highlights the design, working principle, recent developmental advances and applications of graphene based nanohybrid aptasensors (GNH-Apts) (since January 2014 to September 2021) with a special emphasis on two major signal-transduction methods, i.e., optical and electrochemical for the monitoring of pesticides, heavy metals, bacteria, antibiotics, and organic compounds from different environmental samples (e.g., water, soil and related). Lastly, the challenges confronted by scientists and the possible future outlook have also been addressed. It is expected that high-performance graphene-based nanohybrid aptasensors would find broad applications in the field of environmental monitoring.
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Aptámeros de Nucleótidos , Técnicas Biosensibles , Grafito , Plaguicidas , Grafito/química , Aptámeros de Nucleótidos/química , Técnicas Biosensibles/métodos , Monitoreo del AmbienteRESUMEN
The present study evaluated the presence of Salmonella enterica in Pakistani backyard poultry. A total 48 chickens from 4 backyard poultry breeds with the clinical presentation of S. enterica infection were randomly selected from villages in the Punjab Province. Cloacal swabs from live poultry and liver samples from the dead birds were collected for bacterial culture and biochemical identification. Liver and spleen samples from dead birds were evaluated for gross and histopathological changes. Bacterial isolates were subjected to PCR and sequencing of ratA gene. Biochemical identification revealed 5/48 (10.42%) chickens positive for S. enterica. Gross pathology included enlarged, discoloured and congested liver and congested spleen. Histopathology demonstrated congestion of sinusoidal capillaries, cellular swelling and cellular/ballooning degeneration, congestion of central hepatic vein, granular hepatocytic cytoplasm and the presence of variable-sized vacuoles in hepatocytes. The PCR yielded a S. enterica specific amplicon (1047 bp). All liver samples that were positive for S. enterica by biochemical tests, were also positive by PCR. The ratA gene sequencing revealed a close resemblance with S. enteritidis isolates from humans. The present study highlights zoonotic risk from backyard poultry and suggests that PCR can be used as an alternate method for rapid detection of Salmonella serovars.
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Pollos , Enfermedades de las Aves de Corral , Salmonelosis Animal , Salmonella enterica , Animales , Salmonella enterica/aislamiento & purificación , Salmonella enterica/genética , Salmonella enterica/clasificación , Pakistán , Salmonelosis Animal/microbiología , Salmonelosis Animal/diagnóstico , Enfermedades de las Aves de Corral/microbiología , Pollos/microbiologíaRESUMEN
Citrus disease Huanglongbing (HLB) causes sparse (thinner) canopies due to reduced leaf and shoot biomass. Herein, we present results demonstrating the possible mechanisms behind compromised leaf growth of HLB-affected 'Valencia' sweet orange trees by comparing morphological, transcriptome, and phytohormone profiles at different leaf development phases (1. buds at the start of the experiment; 2. buds on day 5; . 3. leaf emergence; 4. leaf expansion; and 5. leaf maturation) to healthy trees. Over a period of 3 months (in greenhouse conditions), HLB-affected trees had ≈40% reduction in growth traits such as tree height, number of shoots per tree, shoot length, internode length, and leaf size compared to healthy trees. In addition, buds from HLB-affected trees lagged by ≈1 week in sprouting as well as leaf growth. Throughout the leaf development, high accumulation of defense hormones, salicylic acid (SA) and abscisic acid (ABA), and low levels of growth-promoting hormone (auxin) were found in HLB-affected trees compared to healthy trees. Concomitantly, HLB-affected trees had upregulated differentially expressed genes (DEGs) encoding SA, ABA, and ethylene-related proteins in comparison to healthy trees. The total number of cells per leaf was lower in HLB-affected trees compared to healthy trees, which suggests that reduced cell division may coincide with low levels of growth-promoting hormones leading to small leaf size. Both bud dieback and leaf drop were higher in HLB-affected trees than in healthy trees, with concomitant upregulated DEGs encoding senescence-related proteins in HLB-affected trees that possibly resulted in accelerated aging and cell death. Taken together, it can be concluded that HLB-affected trees had a higher tradeoff of resources on defense over growth, leading to sparse canopies and a high tree mortality rate with HLB progression.
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The purpose of this research was to estimate the thermal characteristics of tri-HNFs by investigating the impacts of ternary nanoparticles on heat transfer (HT) and fluid flow. The employment of flow-describing equations in the presence of thermal radiation, heat dissipation, and Hall current has been examined. Aluminum oxide (Al2O3), copper oxide (CuO), silver (Ag), and water (H2O) nanomolecules make up the ternary HNFs under study. The physical situation was modelled using boundary layer analysis, which generates partial differential equations for a variety of essential physical factors (PDEs). Assuming that a spinning disk is what causes the flow; the rheology of the flow is enlarged and calculated in a rotating frame. Before determining the solution, the produced PDEs were transformed into matching ODEs using the second order convergent technique (SOCT) also known as Keller Box method. Due to an increase in the implicated influencing elements, several significant physical effects have been observed and documented. For resembling the resolution of nonlinear system issues come across in rolling fluid and other computational physics fields.
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The flow of a fluid across a revolving disc has several technical and industrial uses. Examples of rotating disc flows include centrifugal pumps, viscometers, rotors, fans, turbines, and spinning discs. An important technology with implications for numerous treatments utilized in numerous sectors is the use of hybrid nanofluids (HNFs) to accelerate current advancements. Through investigation of ternary nanoparticle impacts on heat transfer (HT) and liquid movement, the thermal properties of tri-HNFs were to be ascertained in this study. Hall current, thermal radiation, and heat dissipation have all been studied in relation to the use of flow-describing equations. The ternary HNFs under research are composed of the nanomolecules aluminum oxide (Al2O3), copper oxide (CuO), silver (Ag), and water (H2O). For a number of significant physical characteristics, the physical situation is represented utilizing the boundary layer investigation, which produces partial differential equations (PDEs). The rheology of the movement is extended and computed in a revolving setting under the assumption that the movement is caused by a rotatingfloppy. Before the solution was found using the finite difference method, complicated generated PDEs were transformed into corresponding ODEs (Keller Box method). A rise in the implicated influencing factors has numerous notable physical impacts that have been seen and recorded. The Keller Box method (KBM) approach is also delivered for simulating the determination of nonlinear system problems faced in developing liquid and supplementary algebraic dynamics domains. The rate of entropy formation rises as the magnetic field parameter and radiation parameter increase. Entropy production rate decreases as the Brinkman number and Hall current parameter become more enriched. The thermal efficiency of ternary HNFs compared to conventional HNFs losses to a low of 4.8% and peaks to 5.2%.
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Solar radiation, which is emitted by the sun, is required to properly operate photovoltaic cells and solar water pumps (SWP). A parabolic trough surface collector (PTSC) installation model was created to investigate the efficacy of SWP. The thermal transfer performance in SWP is evaluated thru the presence of warmth radiation and heat cause besides viscid dissipation. This evaluation is performed by measuring the thermal transmission proportion of the selected warmth transmission liquid in the PTSC, known as a hybrid nano-fluid. Entropy analysis of Oldroyd-B hybrid nano-fluid via modified Buongiorno's model was also tested. The functions of regulating parameters are quantitatively observed by using the Keller-box approach in MATLAB coding. Short terms define various parameters for tables in velocity, shear pressure and temperature, gravity, and Nusselt numbers. In the condition of thermal radiation and thermal conductivity at room temperature, the competence of SWP is proven to be enhanced. Unlike basic nano-fluids, hybrid nano-fluids are an excellent source of heat transfer. Additionally, with at least 22.56% and 35.01% magnitude, the thermal efficiency of AA7075-Ti-6Al-4 V/EO is higher than AA7075-EO.