<abstract xmlns="http://www.w3.org/1999/xhtml">

This paper constitutes a new technological solution for the exploitation of one of the most important geothermal deposits located in the locality of Biskra (South-east Algeria). This is the Albian aquifer whose hot waters from boreholes, hot springs and spas are poorly exploited while ambient temperatures during winter periods reach very low levels, especially at night. The principle of this geothermal system is to immerse a PVC tubular water-air exchanger in a pool permanently supplied with hot water from a low-energy geothermal borehole with a high flow rate. The choice of PVC material is attributed to the fact that hot geothermal waters are generally of an aggressive composition to steels and metals in general. The geothermal air heater allows the heating of the ambient cold air which is introduced into the exchanger and then extracted hot using an extraction fan. The hot air is then diffused into premises for heating during the winter season. The improvement in the performance of this type of exchanger is highlighted, in particular by acting on the number of pipes of the exchanger and the air flow rate using geothermal energy (low energy) as a source of renewable and clean energy. The experimental results obtained showed that the energy gain is a function of the length of the exchanger and the air flow rate. This gain can be up to 20°C between the inlet and outlet of the miniature exchanger model, which means that the proposed solution could be technically feasible.
</abstract>

Feasibility Study of New Geothermal System for Heating Premises and Thermal Complexes: Experimental Investigation of Water-Air Heat Exchanger in the East of Algeria

<abstract xmlns="http://www.w3.org/1999/xhtml">

The structural parameters and the elastic properties of orthorhombic LiBeH3 material were predicted theoretically using the density functional theory (DFT). The exchange-correlation potential term was treated using the local density approximation (LDA). Our values of the structural parameters and elastic constants predicted for LiBeH3 material agree well with other results of the literature.
The bulk modulus calculated from the BFGS technique is comparable with the value obtained from the elastic constants. The universal anisotropy factor, Young’s and shear moduli, Poisson’s ratio, Pugh’s ratio, Lame’s coefficients and the microhardness were also determined for an ideal polycrystalline LiBeH3 material. Based on the results of Poisson’s ratio and Pugh’s ratio obtained in this work, this hydride material would be classified as a brittle material in nature.
We estimate also the elastic wave velocities, the Debye temperature and the acoustic impedance of the polycrystalline material. Our predicted values obtained from the local density approximation for LiBeH3 material agreed well with the data of the literature obtained from the generalized gradient approximation (GGA).
</abstract>

Radiation and Nanostructure (LPMRN(,University of Mohamed El Bachir El Ibrahimi-Bordj Bou Arreridj

Laboratory of Materials and Electronic Systems, Faculty of Sciences and Technology

University of Mohamed El Bachir El Ibrahimi-Bordj Bou Arreridj

Département des Sciences Techniques, Faculté de la Technologie

Structural and Mechanical Properties of Orthorhombic LiBeH3: Ab-Initio Study

<abstract xmlns="http://www.w3.org/1999/xhtml">

In today’s world of industrial progress, pollution is a major concern, especially water pollution. Considered a real danger to mankind, this article looks at the treatment of water contaminated by textile dyes, which has become a danger to humans and the environment. As an example, we have chosen the green dye FB (anionic type) which is found in the rejects of a textile factory ENADITEX in the industrial zone of the wilaya of ORAN - ALGERIA, this dye is among the most used in the textile industry. The method adopted for dye removal is adsorption by natural perlite. The Experimental results showed that adsorption of the green dye FB on the porous solid studied: natural perlite, gave a removal rate of 87.51% for 60 minutes. The adsorption isotherms of the adsorbent/adsorbate systems studied are satisfactorily described by the two mathematical models Freundlich and Temkin. All the results obtained show that the adsorption kinetics of the green dye FB by the solid material is well described by the second-order model. The adsorption reaction is a physisorption, as the thermodynamic study demonstrated.
</abstract>

Laboratory of Materials (LabMat), National Polytechnic School Oran

Multi-scale Modeling and Simulation Laboratory, Department of Physics, Faculty of Exact Sciences, Department of Physics

Laboratory of Micro and Nanophysics (LaMiN)

Materials Science and Applications Laboratory (LSMA), Faculty of Sciences and Technology

Textile Dye Adsorption By Natural Perlite

<abstract xmlns="http://www.w3.org/1999/xhtml">

This study investigates the mechanical, electronic, and thermodynamic properties of B2 NiAl alloyed with Sb, ranging from 0% to 100%. The calculations were conducted using the WIEN2k code based on the full potential linearized augmented plane wave (FP-LAPW) method within the density functional theory (DFT) framework. Generalized Gradient Approximation (GGA) was employed to approximate the exchange-correlation energy. Our analysis of formation enthalpy indicates a preference for Sb to substitute Al sites. Furthermore, we have observed that the mechanical properties of NiAl can be enhanced by adjusting the chemical composition of Sb. Specifically, an increase in antimony content from 0% to 75% results in a notable improvement in ductility tensile, elevating it from 1.92 to 10.72. Conversely, this alteration diminishes the material’s strength.
Moreover, both the band structures and density of states (DOS) indicate the metallic behavior exhibited by all NiAl1-xSbx compounds. In addition, we employ the Gibbs2 code to calculate thermodynamic properties, shedding light on the influence of temperature and pressure on the volume, heat capacity, Debye temperature and entropy S of NiAl1-xSbx.
</abstract>

Electrical Engineering Department, Faculty of Applied Science

Effect of SB Addition on Mechanical Electronic and Thermodynamic Properties of Intermetallic B2-NIAL: First Principles Study

<abstract xmlns="http://www.w3.org/1999/xhtml">
The size and shape of solar box cooker is determined by the volume of the vessel, which in turn depends on the number of family members. The primary objective of this study is to overcome the obstacles inhibiting researchers from crafting solar box cookers tailored to their specific research needs, as well as hindrances preventing manufacturers from effectively bringing them to market. This experimental study aims to identify two novel optimal volumetric efficiencies (VE1 and VE2) to minimize cooking time. To achieve this goal, we employed two identical solar box cookers made from the same materials and four vessels. The results obtained clearly show that the absorber temperature reached a maximum value of 124.9 °C and the boiling time was the shortest 02h50 when the first volumetric efficiency VE1 had the least value of 6.2% and the second volumetric efficiency VE2 had the greatest value of 100%. It is concluded that these two volumetric efficiencies could serve as benchmark parameters for future research, providing a standardized reference for developing solar box cookers of varied shapes and sizes under the same climatic conditions.
</abstract>

Department of renewable energies, University Kasdi Merbah

Engineering Laboratory of Water and Environment in Middle Saharian

Laboratory of Promotion and Valorization of Saharan Resources (VPRS)

Laboratory of Mechanical Control, Tests, Measurements and Simulations

Faculty of Mathematics and Material Sciences, University Kasdi Merbah

Experimental Investigation on Two Novel Standard Parameters to Improve the Performance of Solar Box Cookers

<abstract xmlns="http://www.w3.org/1999/xhtml">
This work is a comparative study of the effect of two different annealing methods on copper oxide (CuO) nanoparticle properties obtained previously by direct precipitation method. The prepared samples were annealed in air at various temperatures (300, 400, 500°C) for 1 hour. Then they were characterized by employing scanning electron microscopy (SEM), X-ray diffraction (XRD), UV-Visible, and Fourier Transform Infrared (FT-IR) spectroscopy. The main results revealed an increase in the grain size in both methods as the annealing temperature increases. It reaches 30.93 nm in RTA and 26.75 nm in STA at 500°C. XRD spectra showed, in the case of RTA at 500 °C, a significant decrease in the intensity corresponding to the (002) and (111) orientations. This result indicated that beyond 400 °C, one hour of RTA is not suitable for enhancing CuO nanoparticle crystallinity compared to STA. The optical analysis demonstrated that the energy of the optical band gap in STA is higher than that in RTA. It reaches 2,88 eV at 500°C using RTA which is close to the gap value of CuO in the range of 1.8–2.8 eV. FT-IR results showed, for both methods, the presence of characteristic peaks of the Cu-O bonds in the monoclinic CuO structure without any trace of Cu2O structure. Nevertheless, samples exposed to RTA for one hour are more susceptible to absorbing species of C=O bond (C=O bond is due to the atmospheric CO2 absorption and the presence of organic impurities from the synthesis process) than those of STA. Hence, RTA at 500 °C is far from producing CuO nanoparticles with preferred characteristics; it needs further research to examine the effect of higher temperature by controlling the annealing time.
</abstract>

Effect of Rapid Thermal Annealing on CuO Nanoparticles

<abstract xmlns="http://www.w3.org/1999/xhtml">
In this paper, we have performed first-principles calculations on the structural and optoelectronic properties of Cu2GeS3 compound in the Cc and Imm2 structures. We have applied the linear augmented plane wave method for all electrons (FPLAPW), which is based on density functional theory (DFT) by using the local density approximation (LDA) and the Perdew-Burke-Ernzerhof (PBE) generalized gradient approximation (GGA). In addition, the modified Becke Johnson Tran and Blaha potential (TB-mBJ) combined with the Hubbard potential (U), which successfully corrects the band gap problem.
The structural properties such as lattice parameter, compressibility modulus and its derivative for Cu2GeS3-Cc are in good agreement with the available data, but for Cu2GeS3-Imm2 there is no research work in the literature. The band structure results show that the Cu2GeS3-Cc compound has a direct gap (Γ-Γ) and that Cu2GeS3-Imm2 is a metal.
The optical properties are calculated by determining the real and imaginary parts of the dielectric function ε(ω), the absorption coefficient, the reflectivity and the refractive index. These results indicate that these alloys are very useful for UV photo catalysis applications.
</abstract>

Hydrometeorological Institute for Training and Research IHFR

Laboratory of Micro and Nanophysics (LaMiN), National Polytechnic School Oran

Laboratory of Materials(LabMat), National Polytechnic School Oran

Laboratory of Analysis and Application of Radiation LAAR

University of Oran of Sciences and Technology Mohamed Boudiaf

Structural, Electronic and Optical Properties of Cu2GeS3. A First Principles Study

<abstract xmlns="http://www.w3.org/1999/xhtml">

In this present work, we will study the physical properties of a brand new semiconductor material. the structural stability and the electronic properties of Scandium Arsenide (ScAs) and Aluminum Arsenide (AlAs) semiconductors as well as their ternary alloys (AlxSc1-xAs, 0≤ <italic>x</italic>≤1) in both rocksalt RS (B1) and zincblende ZB (B3). Calculations on both structures are done the method (FPLMTO, <italic>Full Potential Linear Muffin Tin</italic>). In the framework of density functional theory (DFT). The exchange-correlation potential was calculated using both the <italic>Local Density Approximation</italic> and the <italic>Generalized Gradient Approximation</italic>.
The structural parameters of AlxSc1-xAs alloys, such as the lattice constant, the bulk module and its derivative are calculated. The lattice parameter deviates slightly from the line of <italic>Vegard’s Law</italic> in B3 structure, while the deviation was more pronounced in B1 structure.
The calculations showed a phase transition from the ZnS phase (B3) to the RS phase (B1) at pressures (7, 10.5, 14.0 and 23.0 Gpa in LDA and (10.0, 12.5, 10.0 and 25.0 GPa) in GGA for x = 0.25, 0.50, 0.75 and 1.00) respectively.The calculated electronic properties showed that in phase B1, there exists an energy band (X-X) with a direct gap at x = 0.00. On the other hand, in phase B3, there are two kinds of energy bands, of direct gap (Γ-Γ) for x = 0.25, 075 and 1.00, the second band is of indirect gap (Γ-X) for x = 0.50, suggesting the possibility to be used in the long wavelength optoelectronic applications. The deviation of The calculated band gap deviation from linear behavior was significant in both structures. The AlxSc1-xAs alloys were found to be semiconducting at x=0 in the B1 phase and at x=0.25, 0.50, 0.75 and 1 in the B3 phase. Concerning calculations of the optical properties of the ternary AlxSc1-xAs alloy at concentrations x= 0.25, 0.50 and 0.75 in the ZnS (B3) phase, and from our bibliographic research we are sure that no reference exists in the literature. Our work can therefore be used as a reference for future research. Our simulation results are in good agreement with those obtained theoretically and experimentally.
</abstract>

Computer Science and Mathematics Laboratory, Physics Department, Faculty of Science and Applied Science

University Mohamed El Bachir El Ibrahimi of Bordj Bou Arreridj

Study of the Phase Transition and Physical Properties of AlAs, ScAs and AlxSc1-XAs Compounds by the FP-LMTO Method

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Volume 65 (2023): Issue 1 (December 2023)

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Annals of West University of Timisoara - Physics

 The first issue of the Annals of the West University of Timisoara, was published in 1963 under the name of Mathematical and Physical Sciences Series, and it was issued on yearly basis ever since. Since 2002 the journal is being published in a new graphical format, as the Annals of the West University of Timisoara, Physics Series. The journal welcomes manuscripts presenting information not previously published in journals, in the areas of Materials Science, Theoretical and Computational Physics, Applied Physics, Medical Physics. The submitted manuscripts are peer-reviewed, insuring a high standard of scientific quality to the accepted articles.  Why subscribe and read  The journal publishes current and original research results in the fields of Materials Science, Theoretical and Computational Physics, Applied Physics, Medical Physics.  Why submit   Fast review and publication process  Fast and constructive peer review   Archiving  Sciendo archives the contents of this journal in Portico - digital long-term preservation service of scholarly books, journals and collections.  Plagiarism Policy  The editorial board is participating in a growing community of Similarity Check System's users in order to ensure that the content published is original and trustworthy. Similarity Check is a medium that allows for comprehensive manuscripts screening, aimed to eliminate plagiarism and provide a high standard and quality peer-review process. 

Annals of West University of Timisoara - Physics

AHEAD OF PRINT

Feasibility Study of New Geothermal System for Heating Premises and Thermal Complexes: Experimental Investigation of Water-Air Heat Exchanger in the East of Algeria

Structural and Mechanical Properties of Orthorhombic LiBeH₃: Ab-Initio Study

Textile Dye Adsorption By Natural Perlite

Effect of SB Addition on Mechanical Electronic and Thermodynamic Properties of Intermetallic B2-NIAL: First Principles Study

Experimental Investigation on Two Novel Standard Parameters to Improve the Performance of Solar Box Cookers

Effect of Rapid Thermal Annealing on CuO Nanoparticles

Structural, Electronic and Optical Properties of Cu₂GeS₃. A First Principles Study

Study of the Phase Transition and Physical Properties of AlAs, ScAs and Al_xSc_1-XAs Compounds by the FP-LMTO Method

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