In this paper, an experimental study was conducted to enhance the thermal performance of a double-pass solar air heater (SAH) using phase change material (PCM) for thermal storage at climatic conditions of Baghdad city - Iraq. The double-pass solar air heater integrated with thermal storage system was manufactured and tested to ensure that the air heating reserved after the absence of the sun. The rectangular cavity filled with paraffin wax was used as a latent heat storage and incorporated into the lower channel of solar air heater. Experiments were carried out to evaluate the charging and discharging characteristics of two similar designed solar air collectors with and without using phase change material at a constant

This study focused on the synthesis of novel polymers incorporating the 1,3,4-oxadiazole ring. Four polymers were specifically prepared by blending polymers (6-9) with polyvinyl alcohol (PVA) in defined ratios, resulting in the formation of blended polymers (10-13). The synthesized polymers were characterized using Fourier Transform Infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (1H-NMR). The results showed that the structure aligned with the proposed synthetic polymers. Furthermore, the physical and thermal properties were studied using scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). Additionally, the biological activity was examined against two s

This study focused on the synthesis of novel polymers incorporating the 1,3,4-oxadiazole ring. Four polymers were specifically prepared by blending polymers (6-9) with polyvinyl alcohol (PVA) in defined ratios, resulting in the formation of blended polymers (10-13). The synthesized polymers were characterized using Fourier Transform Infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (1H-NMR). The results showed that the structure aligned with the proposed synthetic polymers. Furthermore, the physical and thermal properties were studied using scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and Differential Scanning Calorimetry (DSC). Additionally, the biological activity was examined against two s

The study aims to set an image to the mechanisms of the skills of the 21st century in the educational competencies of the basic education stage. To achieve this aim, a qualitative research design has been adopted in its analytical content analysis way. The study has arrived to the following conclusions:  the availability of: the communicative and team work skills with a percentage of 25.9%, linguistic competency with a percentage of 24.6%, the skills of local and global citizenship, creativity, and problem solving with a percentage of 13.6%, critical thinking with a percentage of 10.38%, technological culture with a percentage of 5.8%, pioneerism and initiativeness with a percentage of 10.38%, technological culture with a percentage of

Objectives: Successful endodontic treatment outcome requires effective shaping and cleaning of root canals. This study aims to evaluate the smear layer removal after continuous chelation (CC) ) NaOCL\HEDP( and sequential chelation (SC) )NaOCL\EDTA( and their influence on the push-out bond strength (POBS) of Bio-C sealer. Materials and Methods: Palatal roots of the maxillary first molar (n=72) were divided into four groups (n=18) as follows: 3% NaOCL, SC: 3% NaOCL followed by 17% EDTA, CC: 3% NaOCL \9% HEDP and Distilled water. Thirty-two roots (n=8/group) were split longitudinally for smear layer evaluation using SEM. Forty roots were obturated with Guttapercha and Bio-C sealer using a single cone technique. Thre

As long as the place in which a person lives has a meaning and temporal dimensions , memory is the main axis of these dimensions , today , city centers and old historical sectors of cities are abandoned , and began to turn into slums , the contradiction between old and historical sectors led cities to lose their identity while people lost their sense of belongingness to the old sectors where their ancestors used to live . The old city of Hilla used to have social , historical and cultural role on determining the identity . The study problem can be summarized as the ( lack of studies regarding the impact of historical memory related to Hilla old city on social and cultural mobility ) , the study hypothesis claims that the social , histori

The aim of the research is to indicate the degree of arrangement of the tax branches discussed and the level of efficiency of their performance according to the dimensions approved in the tax diagnostic tool (TADAT). The checklist has been approved as a main tool in collecting data and information from the tax branches of the General Authority for Taxes and the number (8) branches represented by (Karrada , Karakh Center, Al-Rusafa, New Baghdad, Al-Dora, Karakh Al-Tafim, Al-Kadhimiya, Al-Bayaa),  The statistical program (spss) was used to calculate the weighted arithmetic media, and we reached the research to a number of conclusions, the most important of which were: - Each of the subsections (Karkh Al-Ahram and Karrada) achieved an