Drying of beetroots (Beta vulgaris L.) using oven dryer

Removal of moisture from food is popularly called drying and it is one of the most vital preservation techniques used in the food industry. In this study, the beetroots (Beta vulgaris L.) were dried in a laboratory oven dryer. The samples of fresh beetroots were dehydrated under a temperature of 50°C. The experimental study selected three different forms of the product, we choose a square form with (5 × 5 cm) and thickness e = 5 mm, a semi-circle form with thickness e = 5 mm and diameter D = 5 mm, and a triangle form with (5 × 5 × 5 cm) and thickness e = 4 mm. The main objective of the present study is to find the selection of the drying techniques essential to producing high-quality dried products in a rational time. The results give the moisture ratio of the different forms of the beetroot product as a function of time drying, while the triangle form responded to the drying process faster than the other two forms. Highlights Beets dried at 50 °C in oven using 3 geometric shapes. Triangle shape dried fastest due to smaller thickness. Moisture ratio dropped to nearly zero after 325 min. Square shape retained more water and dried slower. Drying time linked more to thickness than shape

Corrosion inhibition effect of arabic gum on Cu-WC nanocomposite coating synthesized by electrodeposition technology

Nanostructured Cu-WC composite coatings were electrodeposited by co-deposition process onto pretreated steel substrate from an acidic sulfate electrolyte bath containing various amount of dispersed WC powder. The analysis by scanning electron microscopy shows those Cu-WC composite coatings containing cracks and random distribution of the oval-shaped WC particles. The X-ray diffraction (XRD) reveals that the structure of Cu-WC coatings is controlled by the WC powder amounts in the electrolyte baths. The average crystallite size was calculated by use X-ray diffraction analysis and its increasing is proportional to the enhancement of WC solid particles amount. The crystallite structure was fcc for electrodeposited Cu-WC nanocomposite coatings. The potentiodynamic polarization and electrochemical impedance spectroscopic studies reveal that grain refinement offers the best corrosion resistance. Arabic gum shows that it is an anodic inhibitor with high inhibitor efficiency reaches 70.95%. IR spectroscopy analysis shows several functional groups responsible for high inhibitor efficiency. Highlights Cu-WC coatings were electrodeposited with varying WC content onto steel substrates. SEM and XRD showed random WC distribution and fcc structure with increasing grain size. 10 g/L WC coating had the best corrosion resistance in 3.5% NaCl. Arabic gum improved corrosion resistance, acting as an effective anodic inhibitor. EIS confirmed max inhibitor efficiency of 70.95% at 25 g/L WC with Arabic gum

Organoclay As a Potential Eco-friendly Substitute Of Chalk In The Manufacturing Of The PVC Based Electric Cable

The aim of this work was to study the effects of an organoclay on the properties of a polyvinyl chloride polymer and to compare the obtained results to polyvinyl chloride/chalk counterpart in order to replace the no eco-friendly and no-economic chalk by the cheap and eco-friendly organoclay in the electric cable polyvinyl chloride manufacturing. The obtained nanocomposites were prepared by dry blending followed by extrusion. The x-ray diffraction analysis evidenced an intercalation of the polyvinyl chloride chains between organoclay platelets. The thermal stability (Beilstein test) of the nanocomposite was greatly improved and thermgravimetric analysis (TGA) showed that the formulation containing 1 wt % of organoclay is the more thermally stable up to 240 °C. Differential scanning analysis showed that the glass transition temperature of the nanocomposite is higher than the neat polyvinyl chloride. A rheological analysis revealed that the addition of organoclay had not damaged the processability of the nanocomposite. Scanning electronic microscopy analysis revealed a uniform dispersion of the organoclay particles in the polyvinyl chloride matrix. The PVC based organoclay exhibits properties better than PVC based chalk used in the industry. So, the eco-friendly organoclay can be a good alternative to the expensive and irritating chalk. Highlights 1% organoclay improves PVC strength, ductility, and thermal stability. XRD shows intercalation at 1% organoclay, enhancing composite structure. DSC confirms higher Tg for 1% organoclay due to chain confinement. Organoclay offers better processability and lower energy use than chalk. SEM reveals uniform dispersion only at low organoclay loading

On the Kernel Conditional Density Estimator with Functional Explanatory Variable

This article focuses on the relationship between a scalar-explained random variable Y and a functional explanatory random variable X. Indeed, Through this work, we aim to estimate the conditional probability density f (y/x) when the explanatory variable X is functional using the kernel method. More precisely, we will present a numerical application based on simulated samples, with the aim of, on the one hand, highlighting the implementation of the estimator in question and the impact of using a symmetric kernel on its quality. On the other hand, analyzing the performance of this estimator as a function of the sample size, the hypothesis imposed on the smoothing parameters (The smoothing parameters in the X direction and the Y direction are independent and the smoothing parameter in the X direction is the same as that in the Y direction) and the norm used in its construction.  AMS subject classification. Primary 62G05; 62G07; Secondary 62R10. Communicated Editor: A. Necir. Manuscript received Jan 22, 2025; revised April 15, 2025; accepted May 25, 2025; published Jun 02, 2025.References [1] Bashtannyk, D. M., & Hyndman, R. J. (2001). Bandwidth selection for kernel conditional density estimation. Computational Statistics & Data Analysis, 36(3), 279-298. Search in Google Scholar. https://doi.org/10.1016/S0167-9473(00)00046-3 [2] Benhenni, K., Ferraty, F., Rachdi, M., & Vieu, P. (2007). Local smoothing regression with functional data. Computational Statistics, 22(3), 353-369.   ‏Search in Google Scholar. https://doi.org/10.1007/s00180-007-0045-0.  [3] Bosq, D. (2000). Linear processes in function spaces: theory and applications (Vol. 149). Springer Science & Business Media.‏ Search in Google Scholar. View a book [4] Chen, S. X. (1999). Beta kernel estimators for density functions. Computational Statistics & Data Analysis, 31(2), 131-145.‏ Search in Google Scholar. https://doi.org/10.1016/S0167-9473(99)00010-9 [5] Chen, S. X. (2000). 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The Impact of Imperfect Vaccination on Infectious Disease Transmission in an Age-Structured Population

In this paper, we consider the influence of imperfect vaccination on the spread of infectious diseases in an age-structured population. The benefits of vaccination, even if not perfect, generally outweigh the risks of severe diseases. In a mathematical system, we consider the compartment of susceptible s; vaccinated v and infected i individuals with an age structure. The proposed model is globally analyzed by introducing total trajectories and employing a suitable Lyapunov functional. To illustrate our theoretical findings, we include numerical simulations at the end of the paper. AMS subject classification: 35Q92, 37N25, 92D30. REFERENCES [1] Adimy, M., Chekroun, A., & Ferreira, C. P. (2020). Global dynamics of a differential-difference system: a case of Kermack-McKendrick SIR model with age-structured protection phase. 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CFD Analysis of Hybrid Photovoltaic Thermal (PV/Th) Solar Collector Efficiency Incorporating Ag-AL2O3/water Hybrid Nanofluids

The optimization of energy consumption is closely tied to enhancing the power output of photovoltaic panels. This study offers a numerical investigation of the utilization of hybrid nanofluids (Ag-Al2O3-water) as a cooling fluid in a hybrid photovoltaic thermal (PV/Th) collector, aiming to improve electrical performance by lowering the PV cells operating temperature. The hybrid PV/Th collector comprises a photovoltaic panel (PV) coupled with a thermal collector, including a heat sink equipped with rectangular ribs positioned at the bottom of the PV module. This research explores the impact of critical configuration parameters, such as inlet velocities of working fluid and nanoparticle volume fractions, on the Nu number, PV cell temperature, and both thermal and electrical efficiencies within steady-state operating conditions. The 3D numerical simulation to analyze the overall performance of a hybrid PV/Th collector was conducted using ANSYS Fluent software version 17.1. The numerical findings demonstrate that increasing the nanoparticle volume fraction elevates the cooling fluid\u27s thermal conductivity, consequently enhancing the heat transfer by conduction. Furthermore, higher coolant velocities enhance heat transfer by convection, resulting in a more effective heat transfer rate within the PV/Th system. This, in turn, reduces the operating temperature and significantly enhances the hybrid PV/Th system\u27s overall performance. Highlights Hybrid nanofluid cooling reduces PV cell temp and boosts overall system efficiency. Higher Re numbers and nanoparticle loads enhance thermal and electrical performance. ANSYS CFD showed max total efficiency of 44.7% at Re = 800, Φ = 0.06. Ag-Al2O3 nanofluid outperformed water alone in PV/Th heat transfer. PV cell temp dropped from 60.1°C to 40.6°C using nanofluid at high flow rate

An effective operational matrix method for the solution of non-linear third-order initial value problems

Abstract The present paper provides a new technique using the clique polynomials as basis function for the operational matrices to obtain numerical solutions of third-order non-linear ordinary differential equations. It aims to find all solutions as easy as possible. Numerical results derived using the proposed techniques are compared with the exact solution or the solutions obtained by other existing methods. The new numerical examples were examined to show that the new approach is highly efficient and accurate. The approximate solutions can be very easily calculated using computer program Matlab. Communicated Editor: M. Berbiche. Manuscript received Oct 27, 2024; revised April 24, 2025; accepted May 11, 2025; published June 14, 2025.References [1] Agarwal, R. P. (1986). Boundary value problems from higher order differential equations. World Scientific.‏ Search in Google Scholar. View a Book [2] Adesanya, A. O., Udoh, D. M., & Ajileye, A. M. (2013). 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ERROR ESTIMATION FOR A PIEZOELECTRIC CONTACT PROBLEM WITH WEAR AND LONG MEMORY

We study a mathematical model for a quasistatic behavior of electro-viscoelastic materials. The problem is related to highly nonlinear and non-smooth phenomena like contact, friction and normal compliance with wear. Then, a fully discrete scheme is introduced based on the finite element method to approximate the spatial variable and the backward Euler scheme to discretize the time derivatives. For a numerical scheme, we prove the existence and uniqueness of the solutions, and derive optimal order error estimates under certain regularity assumption on the solution of the continuous problem. AMS subject classification. 35J85 · 49J40 · 47J20 · 74M15. REFERENCES [1] Aoun, M. S. M., Dehda, B., & Douib, B. (2024). Numerical study of a thermo-elasto-viscoplastic contact problem with adhesion using a hybrid method. Studies in Engineering and Exact Sciences, 5(2), e8308-e8308. Search in Google Scholar. https://doi.org/10.54021/seesv5n2-255 [2] Aoun, M. S. M., Selmani, M., & Ahmed, A. A. 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A parametric analysis of the earth air heat exchangers\u27 thermal efficiency and their effect on surrounding soil over time

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