Faculty of technology_PPI

Permanent URI for this collectionhttps://archives.univ-eloued.dz/handle/123456789/116

Browse

Now showing 1 - 20 of 50

Comparative Analysis of Multiple Linear Regression and Generalized Regression Neural Network for Water Temperature Estimation of Fontaine Des Gazelles Reservoir Dam-Biskra, Algeria
(The International Society for Engineers and Researchers (ISER). Istanbul. Turquie, 2024-02-06) MEZIANI, ASSIA
Our research centers on estimating the water temperature of Fontaine de Gazelles Reservoir Dam by analyzing air temperature, relative humidity, solar radiation, atmospheric pressure, wind speed, and precipitation. These variables collectively impact water temperature, reflecting the thermal environment, water vapor content, solar energy, air density, wind-induced processes, and precipitation cooling. We employ Multiple Linear Regression (MLR) and Generalized Regression Neural Networks (GRNN) models for accurate estimates. MLR captures linear dependencies among climate variables, while GRNN model complex nonlinear relationships. Trained on historical data and real-time measurements, both MLR and GRNN demonstrate strong capabilities. MLR achieves high Nash-Sutcliffe Efficiency (0.991 to 0.997) and low Root Mean Squared Error (0.406 to 0.625), while GRNN achieves similar values. Both models consistently exceed a coefficient of determination R2 equal 0.99, indicating a robust correlation, and display low Mean Absolute Error (0.236 to 0.391), affirming their accuracy. This attests to MLR and GRNN's reliability in estimating water temperature for the Fontaine de Gazelles Reservoir Dam. الملخص (باللغة العربية) تركز بحثنا على تقدير درجة حرارة الماء في سد خزان فونتين دي غازيل المتواجد ببسكرة من خلال تحليل درجة حرارة الهواء والرطوبة النسبية والإشعاع الشمسي والضغط الجوي وسرعة الرياح وهطول الأمطار. تؤثر هذه المتغيرات الجوية بشكل اساسي على درجة حرارة الماء، مما يعكس على البيئة ومياه السد، والطاقة الشمسية، وكثافة الهواء، والعمليات التي تحدثها الرياح، والأمطار. في هذا العمل استخدمنا نموذجين الاول يعتمد على الانحدار الخطي والثاني على الشبكات العصبية للانحدار المعمم. للحصول على تقديرات دقيقة لدرجة حرارة مياه السد. النتائج كانت كتالي يلتقط نموذج الانحدار الخطي التبعيات الخطية بين متغيرات المناخ، في حين تقوم الشبكات العصبية بنمذجة العلاقات غير الخطية المعقدة. ومن خلال تدريبهما على البيانات الجوية والقياسات في الوقت الفعلي، أظهر كل من نموذج الانحدار الخطي والشبكات العصبية تقدرات ممتازة. لدرجات حرارة المياه للسد حيث يحقق نموذج الانحدار الخطي كفاءة عالية (حسب قيم ناش للنموذج يتراوح من 0.991 إلى 0.997) والخطأ التربيعي لمتوسط الجذر المنخفض (0.406 إلى 0.625)، بينما تحقق الشبكات العصبية قيمًا مماثلة. يتجاوز كلا النموذجين باستمرار معامل الارتباط الذي يساوي 0.99، مما يشير إلى وجود ارتباط قوي للمتغيرات، ويعرض متوسط خطأ مطلق منخفض (0.236 إلى 0.391)، مما يؤكد دقتهما. وهذا ياكدعلى فعالية ودقة النموذجين في تقدير درجة حرارة المياه لسد فونتين دي غازيل المتواجد ببسكرة.
Enhanced photocatalytic and antiviral activities of CuO@Fe2O3 NC for amoxicillin degradation and SARS-COV-2 treatment
(University of Eloued جامعة الوادي, 2023-12-07) Laouini, Salah Eddine; Legmairi, Souheila; Meneceur, Souhaila; Hasan, Gamil Gamal; Hamdi, Ali Mohammed
Copper oxide nanoparticles (CuO NPs) and CuO NPs decorated with hematite (Fe2O3) nanocomposites (CuO@Fe2O3 NC) were biosynthesized by a green method using Portulaca oleracea leaves extract. The NC were characterized using various techniques, including X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and UV-Vis spectroscopy. The results showed that the synthesized CuO and CuO@Fe2O3 NC were crystalline with a monoclinic crystal structure and contained functional groups responsible for catalytic activity. The size of the nanocomposites ranged from 39.5 to 45.9 nm, and they exhibited a variety of agglomerated or aggregated shapes. The CuO@Fe2O3 NC showed improved photocatalytic activity for the degradation of antibiotics in water and wastewater and promising antiviral activity against SARS-CoV-2, indicating its potential for use in disinfection applications. The study investigated the impact of irradiation time on the photocatalytic degradation of Amoxicillin and found that increasing the irradiation time led to a higher degradation rate. The band gap energy (Eg) for pure CuO NPs was around 2.4 eV and dropped to 1.6 eV with CuO@Fe2O3 NC. In summary, the CuO@Fe2O3 NC has the potential to be an efficient photocatalyst and promising antiviral agent for environmental remediation. The CuO@Fe2O3 nanocomposites have been found to possess a high degree of efficacy in inactivating SARS-CoV-2 infectivity. The results of the study indicate that the nanocomposites exhibit potent anti-viral properties and hold significant potential for use in mitigating the spread of the virus الملخص تم تصنيع الجسيمات النانوية لأكسيد النحاس (CuO NPs) وCuO NPs المزينة بمركبات نانوية من الهيماتيت (Fe2O3) (CuO@Fe2O3 NC) بطريقة خضراء باستخدام مستخلص أوراق Portulaca oleracea. تم تشخيص NC باستخدام تقنيات مختلفة، بما في ذلك حيود الأشعة السينية (XRD)، والتحليل الطيفي للأشعة تحت الحمراء (FTIR) لتحويل فورييه، والمجهر الإلكتروني الماسح (SEM)، والتحليل الطيفي للأشعة السينية المشتتة من الطاقة (EDS)، والتحليل الطيفي للأشعة فوق البنفسجية. أظهرت النتائج أن CuO وCuO@Fe2O3 NC المُصنّعين كانا بلوريين بتركيب بلوري أحادي الميل ويحتويان على مجموعات وظيفية مسؤولة عن النشاط التحفيزي. تراوح حجم المركبات النانوية من 39.5 إلى 45.9 نانومتر، وأظهرت مجموعة متنوعة من الأشكال المتكتلة أو المجمعة. أظهر CuO@Fe2O3 NC نشاط تحفيز ضوئي محسّن لتحلل المضادات الحيوية في الماء ومياه الصرف الصحي ونشاطًا واعدًا مضادًا للفيروسات ضد SARS-CoV-2، مما يشير إلى إمكانية استخدامه في تطبيقات التطهير. بحثت الدراسة في تأثير وقت التشعيع على التحلل الضوئي للأموكسيسيلين ووجدت أن زيادة وقت التشعيع أدى إلى ارتفاع معدل التحلل. كانت طاقة فجوة النطاق (على سبيل المثال) لـ CuO NPs النقية حوالي 2.4 فولت وانخفضت إلى 1.6 فولت مع CuO@Fe2O3 NC. باختصار، يتمتع CuO@Fe2O3 NC بالقدرة على أن يكون محفزًا ضوئيًا فعالًا وعاملًا واعدًا مضادًا للفيروسات للمعالجة البيئية. تم العثور على أن المركبات النانوية CuO@Fe2O3 تمتلك درجة عالية من الفعالية في تعطيل عدوى SARS-CoV-2. تشير نتائج الدراسة إلى أن المركبات النانوية تظهر خصائص قوية مضادة للفيروسات ولها إمكانات كبيرة للاستخدام في التخفيف من انتشار الفيروس
Modélisation de la cinétique de séchage en couche mince de pommes entières en Séchoir solaire indirect
(University of Eloued جامعة الوادي, 2023-03-18) Zine, Ali; Benseddik, Abdelouahab; Saim, Rachid; Laouini, Abdeldjalil; Zelaci, Messaoud
Cette recherche étudie la cinétique de séchage de pommes entières en utilisant un séchoir solaire indirect. L'étude estime la diffusivité efficace de l'humidité et la cinétique de séchage d'échantillon, en utilisant le modèle de diffusion de Fick pour éclairés le transfert d'humidité. La valeur de diffusivité effective égal 4,82.10-10 m2 /s. Les données expérimentales de teneur en eau sont ajustées par dix modèles empiriques sélectionnés de séchage en couche mince. On suppose que le modèle le mieux adapté est celui qui a le coefficient de détermination le plus élevé R2, le plus bas réduit le quadrant χ2 et l'erreur carrée moyenne RMSE. L'étude conclut que le modèle Midilli-Kucuk modélise avec succès la cinétique de pommes entières. Ces résultats contribuent au développement de méthodes efficaces de séchage de pommes et donnent un aperçu de la cinétique de séchage. تتضمن هذه الدراسية حركية التجفي لشرائح التفاح الناضج بواسطة المجفف الشمسي. في هذه الدراسة تم تقدير انتشارية الرطوبة داخل شرائح التفاح وذلكباستعمال قانون فيك للإنتشار من أجل توضيح انتقالية الرطوبة داخل الشرائح وكانت النتيجة التقريبية تقدر ب4.82*10-10 متر /الثانية. النتائج التجريبية المتحصل عليها طبقت عليها ست نماذج لمعرفة النموذج الأقرب الذي يحاسي حركية التجفيف فقد وجدنا ان النموذج الأقرب هو نموذج ميدلي كروك.
Green Synthesized of Ag/Ag2O Nanoparticles Using Aqueous Leaves Extracts of Phoenix dactylifera L. and Their Azo Dye Photodegradation
(MDPI, 2021-06-25) Laouini, Salah Eddine; Bouafia, Abderrhmane; Soldatov, Alexander V
In this study, silver/silver oxide nanoparticles (Ag/Ag2O NPs) were successfully biosynthesized using Phoenix dactylifera L. aqueous leaves extract. The effect of different plant extract/precursor contractions (volume ratio, v/v%) on Ag/Ag2O NP formation, their optical properties, and photocatalytic activity towards azo dye degradation, i.e., Congo red (CR) and methylene blue (MB), were investigated. X-ray diffraction confirmed the crystalline nature of Ag/Ag2O NPs with a crystallite size range from 28 to 39 nm. Scanning electron microscope images showed that the Ag/Ag2O NPs have an oval and spherical shape. UV–vis spectroscopy showed that Ag/Ag2O NPs have a direct bandgap of 2.07–2.86 eV and an indirect bandgap of 1.60–1.76 eV. Fourier transform infrared analysis suggests that the synthesized Ag/Ag2O NPs might be stabilized through the interactions of -OH and C=O groups in the carbohydrates, flavonoids, tannins, and phenolic acids present in Phoenix dactylifera L. Interestingly, the prepared Ag/Ag2O NPs showed high catalytic degradation activity for CR dye. The photocatalytic degradation of the azo dye was monitored spectrophotometrically in a wavelength range of 250–900 nm, and a high decolorization efficiency (84.50%) was obtained after 50 min of reaction. As a result, the use of Phoenix dactylifera L. aqueous leaves extract offers a cost-effective and eco-friendly method.
Green synthesis of iron oxide nanoparticles by aqueous leaves extract of Mentha Pulegium L.: Effect of ferric chloride concentration on the type of product
(North-Holland, 2020-04-15) Bouafia, Abderrhmane; Laouini, Salah Eddine
In this study, green synthesis of iron oxide nanoparticles was successfully prepared from Mentha pulegium L. leaves extract. The effect of different ferric chloride concentrations on the nanoparticles' iron oxide formation was studied. The obtained nanoparticles were characterized by UV-Vis, FT-IR, XRD, SEM and EDAX techniques are used for this purpose. UV-Vis spectra showed maximum absorption at range 275–301 nm related to the iron oxide. FTIR spectra exhibit a two weak peak at 510 and 594 cm−1 attributed to iron oxide NPs vibration, confirming the formation nanoparticles XRD confirmed the crystalline nature of Fe3O4 and α-Fe2O3 NPs with average size ranged in 22–34 nm. SEM showed that the green synthesizing Iron oxide nanoparticles having in general as cubical shape. As a result, the use of Mentha pulegium L. leaves extract offers its ease, fast, low cost and friendly to the environment compared to other methods.
Green synthesis and characterization of iron oxide nanoparticles by pheonix dactylifera leaf extract and evaluation of their antioxidant activity
(Elsevier, 2020-09-01) Ahmed Abdullah, J Amin; Laouini, Salah Eddine; Bouafia, Abderrhmane; M, Alonso-González; A, Guerrero; A, Romero
The development of green nanotechnology is generating research interest in the ecological biosynthesis of nanoparticles (NPs). In this study, the biosynthesis of stable iron nanoparticles was carried out using Phoenix dactylifera L. extract which is able to reduce iron ions to iron nanoparticles. The process comprises maceration extraction overnight and heat treatment of the extract with iron chloride (FeCl3) at 70 °C for 1 h. X-ray diffraction (XRD), scanning electron microscope (SEM), and Fourier transform infrared spectroscopy (FTIR) were used for nanoparticle characterization. The stability of the bioreduced iron nanoparticle was analyzed using UV-VIS absorption spectra, and their antioxidant and anti-radical activities were measured against PhosPhoMolybdate (PPM) and 2,2-diphenyl-1-picryl-hydrazyl (DPPH), respectively. The results demonstrate that ecological biosynthesis of 2–30 nm stable iron nanoparticles of size with antioxidant activity can be achieved suggesting their possible applications.
Comparative Study of Honey Collected from Different Flora of Algeria
(Journal of Fundamental and Applied Sciences, 2014) Rebiai, A; Lanez, T
The aim of the present study was to evaluate the physical and chemical properties of five Algerian unifloral types of honey. Several physical parameters of honey, such as pH, moisture content, electrical conductivity, total dissolved solids, color intensity and total sugar content, were measured. The mean pH, moisture content, EC and water insoluble solids of Algerian honey were 4.41± 0.58, 15.3 ± 1.5%, 0.324± 0.116 mS/cm and 0.141± 0.065%, respectively. The mean color was 81 ± 72 mm Pfund. The majority of honey samples test results (moisture content, electric conductivity and acidity) levels were within the acceptable range of world honey standards.
Effect of Extraction Methods on Polyphenols, Flavonoids, Mineral Elements, and Biological Activities of Essential Oil and Extracts of Mentha pulegium L
(MDPI, 2021-12-21) Messaoudi, Mohammed; Rebiai, Abdelkrim; Sawicka, Barbara; Atanassova, Maria; Ouakouak, Hamza; Larkem, Imane; Egbuna, Chukwuebuka
ur study evaluated the in vitro antioxidant properties, antibacterial and antifungal activities, anti-inflammatory properties, and chemical composition of the essential oils (EOs), total phenol, and total flavonoid of wild Mentha pulegium L. This study also determined the mineral (nutritional and toxic) elements in the plant. The EOs were extracted using three techniques—hydro distillation (HD), steam distillation (SD), and microwave-assisted distillation (MAD)—and were analyzed using chromatography coupled with flame ionization (GC-FID) and gas chromatography attached with mass spectrometry detector (GC-MS). The antioxidant effects of the EOs were tested with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ABTS (2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid), while the antibacterial and antifungal activities of the EO and methanolic extract were tested using Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Escherichia coli, and Candida albicans. Twenty-six compounds were identified in the essential oil, representing 97.73% of the total oil, with 0.202% yield. The major components were pulegone (74.81%), menthone (13.01%) and piperitone (3.82%). Twenty-one elements, including macro- and micro-elements (Ba, Br, Ca, Cl, Co, Cr, Cs, Eu, Fe, K, Mg, Mn, Mo, Na, Rb, Sb, Sc, Sr, Th, U and Zn), were detected using neutron activation analysis (INAA) and inductively coupled plasma optical emission spectrometry (ICP-OES), with the concentration of mineral element close to the FAO recommendation. The results show that the EOs and extracts from Mentha pulegium L. had significant antimicrobial activities against the microorganisms, including five human pathogenic bacteria, one yeast (Candida albicans), and one phytopathogenic fungi. The in vivo anti-inflammatory activities of the leaf extracts were confirmed. The results indicate that the EOs and extracts from Mentha pulegium L. have promising applications in the pharmaceutical industries, clinical applications, and in medical research.
total polyphenol contents, radical scavenging and cyclic voltammetry of Algerian propolis
(International Journal of Pharmacy and Pharmaceutical Sciences, 2014) Lanez, Touhami; Rebiai, Abdelkrim; Belfar, M Lakhdar
Objective: In this study, we will determine the antioxidant properties of methanolic extract of propolis from Ghardaia and Khanchla provinces of Algeria and will correlate the values with total levels of polyphenolic compounds. Methods: The total polyphenol contents of methanolic extract of propolis were measured by using Folin–Ciocalteu spectrophotometric method. Thereafter, the antioxidant properties of these polyphenols were determined by using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging. All polyphenols extracted were tested using cyclic voltammetry (CV) in aqueous media. The CV was realised to compare the results from spectroscopic method and to electrochemically characterise the propolis polyphenols. Results: The total polyphenolic content in methanolic extract of propolis from Ghardaia and Khanchla was 493.49 and 1423.32 mg gallic acid equivalent/100g of extract, respectively. The IC50 values for scavenging DPPH radical for Ghardaia and Khanchla propolis were 0.03917 mg/mL, 0.01211mg/mL respectively. Antioxidant activity measured by cyclic voltammetry method indicated that methanolic extract of Khanchla propolis had AEAC of 15,61 mg/g. Conclusion: Propolis samples had strong antioxidant activities, and the highest activities were found in Khanchla propolis. Also, among three assays employed in this study (DPPH, RP, CV), the cyclic voltammetry method was recommended as it represented a relatively clean chemical system
In vitro Evaluation of Antioxidant Capacity of Algerian Propolis by Spectrophotometrical and Electrochemical Assays
(Asian Network for Scientific Information, 2011-01-01) Rebiai, A; Lanez, T; Belfar, ML
The aim of the present study was to evaluate the antioxidant capacity and the total phenolic content of propolis extract, obtained from colonies of honeybees located in El-Oued (south of Algeria). The total phenolic content was evaluated using the Folin-Ciocalteu method and the anticoxidant capacity was measured using the following methods: 2, 2-diphenyl-1-picryhydrazyl free radical scavenging capacity and reducing power capacity for spectrophotometrical techniques, ascorbic and gallic acids equivalent antioxidant capacity assays for electrochemical techniques. Both techniques allowed an evaluation of the antioxidant capacity of methanolic propolis extract. The electrochemical techniques were performed by cyclic voltammetry, the results suggest that propolis extract do not reveal similar electrochemical responses to that of ascorbic and gallic acids, suggesting a different electroactive chemical composition and oxidation potential more positive than that of the standard (ascorbic acid), however this does not suggest that propolis has a lower antioxidant capacity. The results suggest also that propolis extract possess antioxidant capacity in vitro conditions.
Chemical composition and antioxidant activity of Apis mellifera bee pollen from northwest Algeria
(Journal of Fundamental and Applied Sciences, 2012-12-31) Rebiai, Abdelkrim; Lanez, Touhami
The aim of this study was to assess the nutritional composition and antioxidant activity of bee pollen produced in the North western region of Algeria. The content of total phenolic compounds, flavonoids, and antioxidant activity using the molybdate ion reduction method were determined. The mean contents of phenolic compounds and total flavonoids were 30.46 ± 8.22 mg of GAE.g–1 pollen and 8.92 ± 5.5 mg of RE.g–1 pollen, respectively. High antioxidant activities were found for the molybdate ion reduction method, with values that ranged from 71.95 to 101.5 μg of GAE.g –1 pollen. The bee pollen of Boufarik showed high antioxidant activity probably due to the high content of phenolic compounds present in pollen.
Doubly-fed induction generator drive based WECS using fuzzy logic controller
(Higher Education Press, 2015-09) Dida, Abdelhak; Ben Attous, Djilani
The purpose of this paper is to improve the control performance of the variable speed, constant frequency doubly-fed induction generator in the wind turbine generation system by using fuzzy logic controllers. The control of the rotor-side converter is realized by stator flux oriented control, whereas the control of the grid-side converter is performed by a control strategy based on grid voltage orientation to maintain the DC-link voltage stability. An intelligent fuzzy inference system is proposed as an alternative of the conventional proportional and integral (PI) controller to overcome any disturbance, such as fast wind speed variation, short grid voltage fault, parameter variations and so on. Five fuzzy logic controllers are used in the rotor side converter (RSC) for maximum power point tracking (MPPT) algorithm, active and reactive power control loops, and another two fuzzy logic controllers for direct and quadratic rotor currents components control loops. The performances have been tested on 1.5 MW doubly-fed induction generator (DFIG) in a Matlab/Simulink software environment.
Comparison Study Between SVM and PWM Inverter in Sliding Mode Control of Active and Reactive Power Control of a DFIG for Variable Speed Wind Energy
(İlhami ÇOLAK, 2012-09-18) Bekakra, Youcef; Ben Attous, Djilani
t- In this paper, we present a comparative study between space vector modulation (SVM) and pulse width modulation (PWM) inverter in sliding mode control (SMC) of active and reactive power control of a doubly fed induction generator (DFIG) for variable speed wind energy. The feasibility and effectiveness of the two methods are demonstrated by simulation results. The obtained results showed that, the proposed SMC with SVM inverter have stator and rotor current with low harmonic distortion and low active and reactive powers ripples than PWM inverter.
Artificial bee colony optimization for economic dispatch with valve point effect
(Higher Education Press, 2014-12) Labbi, Yacine; Ben Attous, Djilani; Mahdad, Belkacem
In recent years, various heuristic optimization methods have been proposed to solve economic dispatch (ED) problem in power systems. This paper presents the well-known power system ED problem solution considering valve-point effect by a new optimization algorithm called artificial bee colony (ABC). The proposed approach has been applied to various test systems with incremental fuel cost function, taking into account the valve-point effects. The results show that the proposed approach is efficient and robust when compared with other optimization algorithms reported in literature.
Particle swarm optimization based optimal power flow for units with non-smooth fuel cost functions
(IEEE, 2009-11-15) Ben Attous, Djillani; Labbi, Yacine
This paper presents a Particle Swarm Optimization (PSO) based algorithm for optimal flow with generating units having non-smooth fuel costs curves while statisfying the constraints such as generator capacity limits, power balance, line flow limits, bus voltages and transformer tap setting, The conventional loed flow and incorporation of the proposed method using PSO has been examined and tested for standard IEEE 30 bus system. The PSO method is demonstrated and compared with conventional OPF method and the intelligence heuristic algorithm such as genetic algorithm, evolutionary programming. The superiority of th method over other methods has been demonstrated on two test cases. From simulation results, it has been found that PSO method is highly competitve for its better general convergence performance
Sliding Mode Controls of Active and Reactive Power of a DFIG with MPPT for Variable Speed Wind Energy Conversion
(Australian Journal of Basic and Applied Sciences, 2011-12) Bekakra, Youcef; Ben Attous, D
This paper presents the study of a variable speed wind energy conversion system based on a Doubly Fed Induction Generator (DFIG) based on a sliding mode control applied to achieve control of active and reactive powers exchanged between the stator of the DFIG and the grid to ensure a Maximum Power Point Tracking (MPPT) of a wind energy conversion system. The proposed control algorithm is applied to a DFIG whose stator is directly connected to the grid and the rotor is connected to the PWM converter. To extract a maximum of power, the rotor side converter is controlled by using a stator flux-oriented strategy. The created decoupling control between active and reactive stator power allows keeping the power factor close to unity. Simulation results show that the wind turbine can operate at its optimum energy for a wide range of wind speed.
Traditional solar distiller improvement by a single external refractor under the climatic conditions of the El-Oued region, Algeria
(Desalin Water Treat, 2020-02-01) Khechekhouche, Abderrahmane; Kabeel, AE; Benhaoua, B; Attia, Mohammed El Hadi; El-Said, Emad MS
Desalination is now successfully practiced in many countries as drinking water supply has become a growing problem in most parts of the world. Algeria, like the Maghreb countries, has generally adopted two desalination processes (membrane processes and distillation processes which require a phase change, evaporation/condensation), the latter method is subject of our study. An experimental study was made on two similar stills with a single slope, size 1 m × 1 m, the first distiller D1 is used as a control and the second distiller D2 has a simple external mirror glued to its backlog. The same experience has been done in different climates with improvement results ranging from 9% to 21%. In our case, a complete study was concerning the improvement, the efficiency, the investment and finally the error analysis of the instrumentations that have not been done before. We obtained a very interesting improvement which varied between 42% and 45%, the efficiency is 35% and the recovery period of the sum invested is recovered in 23 d, which shows that this technique is more favorable under the climatic conditions of the West Southeast region of Algeria than elsewhere.
Thermodynamic analysis and performance of an adsorption refrigeration system driven by solar collector
(Pergamon, 2017-02-05) Ammar, MA Hadj; Benhaoua, B.; Bouras, F.
This paper presents the operating and performance of an adsorption refrigeration system driven by a solar collector. The thermodynamic cycle and the working principle of the system are based on the adsorption phenomena at a steady temperature. The system operates with activated carbon (AC)-methanol as a working pair, and Dubinin-Astakhov (D-A) equation was used to describe this phenomena. Comparative study between different types of AC reveals that the one based on stone coal had an optimal performance coefficient (COP) equal to 0.73 whereas a total energy input to the system is 18740.05kJ and a total daily ice production of 13.65kg at -3° C. The studied case indicates that the optimal performance of the system can be obtained for low ambient and condensation temperature with high evaporation temperature. Ice produced can also be improved when the initial water temperature is low.
Sand dunes effect on the productivity of a single slope solar distiller
(Springer Berlin Heidelberg, 2020-04) Khechekhouche, Abderrahmane; Benhaoua, Boubaker; Manokar, Muthu; Sathyamurthy, Ravishankar; Kabeel, Abd Elnaby; Driss, Zied
Access to drinking water in many parts of the globe is shrinking over the years and much of the water resources are polluted or unpurified. North Africa is facing a huge water shortage due to drought and climate change. Water desalination has become very popular and serves as solar distillation which is proving to be an economical, simple and ecological technique, especially in rural and remote areas. Significant efforts have been made by many researchers in various laboratories to increase and improve the productivity of solar greenhouse distillation. In the present work, emphasis has been placed on the study of a single slope solar distiller having as dimension 50 × 50 cm, in the thickness of the impure water is 1 cm. Natural sand dunes from the El Oued South region of Algeria have been tested as a factor of efficiency improvement. A layer of this sand was deposited on the bottom of the distiller covering the whole surface on which the submit water is emerged. The results show that the productivity of distilled water has unfortunately decreased by 1.46 times.
Elaboration and characterisation of ZnO thin films
(EDP Sciences, 2012) Benramache, S.; Benhaoua, B.; Khechai, N.; Chabane, F.
Abstract – Highly transparent ZnO thin films have been prepared on microscope glass substrate using dip-coating technique. The films were obtained at a concentration of solgel solution is 0.5 M. The structural and optical properties of the ZnO thin films were studied as a function of the annealing temperature varying between 450 to 600 ◦C. From the XRD analysis, the whole obtained films have a hexagonal wurtzite structure with a strong (002) preferred c-axis orientation. The grain size increased with annealing temperature indicating an improvement in the crystallinity of the films. The average transmittance of all the films is about 70–80% as measured by UV-vis analyzer. The band gap increased with the increase of temperature from 3.25 to 3.42 eV. The decrease of the strain of ZnO films is probably due to an improvement of the crystallinity of the films. The best result is achieved at 600 ◦C.

Browse

Recent Submissions