Optimal tilt angle for photovoltaic panels in the Algerian region of El-Oued in the spring season: An experimental study

The tendency to exploit solar energy in the electricity production in Algeria is a priority and a major goal of the Algerian government, and for this reason it seeks to provide all the necessary capabilities to achieve this lofty goal. Photovoltaic electricity is one of the effective technologies for the solar electricity production, but before installing any photovoltaic panel, it is important to determine its optimal tilt angle, and based on this, this study allowed to show the optimal tilt angle of the photovoltaic panels in the Algerian region of El Oued in the spring season, and accordingly, two days (March 21st, 2023, and April 21st, 2023) were chosen to conduct this experimental study. Based on the obtained results, the optimal PV tilt angle for the month of March is 33° and 28° for the month of April. In addition, the greater the amount of solar radiation, the higher the efficiency and productivity of the PV panels, as the highest values for them (6.31 % and 62.17 W, respectively) were recorded on April 21st, 2023. The results of this study will contribute to the correct installation of photovoltaic panels in the Algerian region of El-Oued, especially if the photovoltaic panels are equipped with dual-axis solar tracking systems

STUDY AND NUMERICAL SIMULATION OF SOLAR SYSTEM FOR AIR HEATING

<p>The use of solar energy in sunny countries, is an effective outil for compensate the lack in the energy, their benefits are not related only to its economic benefits but especially for the environmental protection, so we must find solutions to the problems of pollution. This work is a theoretical study of a solar flat plate collector ; air is used as the heat transfer fluid. In this study, we established in first step the calculation of solar radiation in various sites in Algeria (Adrar, El Oued, Bechar, Biskra and Tamanrasset). The second step is the parameters influence study of the sites and climate on the performance of our collector. The results obtained are encouraging for the use of this type in the heating in the winter, also it can be used in different kinds of drying.</p

Spectroscopic investigations of Sm3+doped phosphate glasses: Judd-Ofelt analysis

Highlights- Sm3+-doped Phosphate glasses were prepared by the conventional melt quenching method.- Judd-Ofelt intensity parameters, Ω2, Ω4, and Ω6 were determined and discussed.- Some radiatives parameters of Sm3+ were estimated.- Obtained results make our glasses suitable for laser emission.International audiencePhosphate glasses with chemical compositions of (42– x/2) P2O5-(42– x/2)Na2O-15ZnO–xSm2O3 were synthetized by melt quenching method. We investigated the influence of Sm3+ doping on the optical properties of phosphate glasses. X-Ray Diffraction indicates that the samples have an amorphous structure. DSC measurements show a good thermal stability of phosphate glasses. Using the absorption spectra, Judd-Ofelt analysis was applied to absorption bands of Sm3+ (4f5) to carry out the three phenomenological parameters of Judd-Ofelt (JO). According to the obtained values of Ω2, Ω4 and Ω6, some radiative properties were theoretically determined. Photoluminescence (PL) spectra show three transitions of Sm3+: 4G5/2 → 6H5/2 (600 nm), 4G5/2 → 6H7/2 (564 nm) and 4G5/2 → 6H9/2 (645 nm). The concentration dependency of PL intensity was investigated. The quenching of the PL intensity occurs at the Sm3+ concentration above 1%. The predicted lifetime (τr) calculated by using JO method and the measured lifetime (τmea) determined experimentally for 4G5/2 level, were discussed and compared with those of other works. With the weak spectroscopic quality factors Ω4/Ω6 (0.76), we expect a relatively prominent infrared laser emission

Hollow Organosilica Nanoparticles for Drug Delivery

International audienceThe sol‐gel synthesis of hollow organosilica nanoparticles incorporating amino groups with uniform size are described. These nanoparticles were successfully prepared via a microemulsion method. Then, the hollow nanoparticles were loaded with gemcitabine hydrochloride or methotrexate and studied in MCF‐7 breast cancer cells