An experimental study was conducted to determine the performance of a solar electric refrigeration system. The system contained flat photovoltaic solar panel which absorbs the solar energy and convert it to electrical energy, used to run the refrigeration cycle. Two refrigeration cycles with electrical solar panel were used over a period of 12 months, the first one with classical parts known in refrigeration cycle, while the second one introduced heat exchanger which improves the coefficient of performance by saving the consumed energy. The coefficient of performance of these refrigeration cycles with compressor efficiency 85% are 2.102 and 2.57 respectively. The overall efficiency of the two systems are 18.9% and 23.13%.
Electrospun nanofiber membranes are employed in a variety of applications due to its unique features. the nanofibers' characterizations are effected by the polymer solution. The used solvent for dissolving the polymer powder is critical in preparing the precursor solution. In this paper, the Polyacrylonitrile (PAN)-based nanofibers were prepared in a concentration of 10 wt.% using various solvents (NMP, DMF, and DMSO). The surface morphology, porosity, and the mechanical strength of the three prepared 10 wt.% PAN-based nanofibers membranes (PAN/NMP, PAN/DMF, and PAN/DMSO) were characterized using the Scanning Electron Microscopy (SEM), Dry-wet Weights method, and Dynamic Mechanical Analyzer (DMA). Using DMF as a solvent resulted in a lon
... Show MoreIn this paper, the effect of wear in the fluid film journal bearings on the dynamic behavior of rotor bearing system has been studied depending on the analytical driven of dynamic stiffness and damping coefficients of worn journal bearing. The finite element method was used to modeling rotor bearing system. The unbalance response, critical speed and natural frequency of rotor bearing system have been studied to determine the changes in these parameters due to wear. MATLAB software was used to find the analytical values of dynamic coefficients of journal bearing. The results of rotor mounted on fluid film journal bearings showed that the wear in journal bearing increases the amplitude of unbalance response and decrease critical speed, sta
... Show MoreThe cross section evaluation for (α,n) reaction was calculated according to the available International Atomic Energy Agency (IAEA) and other experimental published data . These cross section are the most recent data , while the well known international libraries like ENDF , JENDL , JEFF , etc. We considered an energy range from threshold to 25 MeV in interval (1 MeV). The average weighted cross sections for all available experimental and theoretical(JENDL) data and for all the considered isotopes was calculated . The cross section of the element is then calculated according to the cross sections of the isotopes of that element taking into account their abundance . A mathematical representative equation for eac
... Show MoreIn this paper the proton, neutron and matter density distributions and the corresponding root mean square (rms) radii of the ground states and the elastic magnetic electron scattering form factors and the magnetic dipole moments have been calculated for exotic nucleus of potassium isotopes K (A= 42, 43, 45, 47) based on the shell model using effective W0 interaction. The single-particle wave functions of harmonic-oscillator (HO) potential are used with the oscillator parameters b. According to this interaction, the valence nucleons are asummed to move in the d3f7 model space. The elastic magnetic electron scattering of the exotic nuclei 42K (J?T= 2- 2), 43K(J?T=3/2+ 5/2), 45K (J?T= 3/2+ 7/2) and 47K (J?T= 1/2+ 9/2) investigated t
... Show MoreBanking institutions are considered one of development foundations,and they also performe active role in supporting national economey and itsinstitutions. Banks became diversed in their activities that specialized Banksbecame one of the constituents of developing work in any activity, especiallyin investiment sector .In view of the importance of insurance sector and thenecessity of developing its divices and its working instituments, studyinginsurance Banking reality became a necessity, because insurance Companies inIraq are suffering of weakness in the level of insurance service, in addition tothe existence of a problem in the relationship between Banks network andinsurance industry.So this research aims to define insurance reality; the
... Show MoreSpecimens of the hedgehog Hemiechinus auritus Gmelin. which were trapped in two places on the Eastern shores of the Tigris River, some 50 and 60 Km, south of Baghdad. central Iraq. were searched for ectoparasites. They revealed the following parasites: One species of Anoplura: polyplex spinulosa (Burm.), family Hoplople uridae, two species of fleas: Synostrnus pallidus (Tasch.) and Ctenocephalides felis (Bouche), family pulicidae, One mite species: Ornithonyssus bacoti (Hirst), family Macronyssidae and two tick species: Rhipicephalus leporis and R. turanicum family Ixodidae. All these ectoparasite species are new records on this hedgehog in Iraq.
Background:As arelationshipbetween gingivitis disease and the presence of the oral protozoa Trichomonastenax has been represented byconsiderable differences among various study population.The purpose of present study is determining the prevalence of T.tenax in patients with gingivitis and healthy subjects. Subjects,Materials and Methods:The presence of the parasite has been diagnosed with 58 patients withgingivitisand 58 healthy persons during the period of the study(April and May 2015) by taken two swabs for each one,microscopic examination was done using saline wet mount method and stained method. Age, sex and brushing teeth habit were in a count. Statistical analysis was done by SPSS program. Results:Gingivitis disease was observed in 5
... Show MoreThis research investigates the engagement of the Iraqi audience with ethnographic programs and their impact on knowledge enhancement and intellectual perspectives. A questionnaire consisting of closed-ended questions was designed and administered to a purposive sample of 400 participants who exclusively follow ethnographic programs and documentary channels. The data were transcribed and subjected to statistical analysis using the SPSS software to ensure reliability and test hypotheses. The findings revealed that Al Jazeera Documentary Channel had the highest viewership percentage among respondents for ethnographic programs, while DW (Deutsche Welle) had the lowest viewership percentage. This suggests that Al Jazee
... Show Moreيتناول البحث شخصية شعرية وأدبية فذة هو محمد صالح بحر العلوم الشاعر العراقي المعروف والمولود في بيت ثوري من بيوتات النجف المعادية للاستعمار البريطاني في مطلع القرن العشرين، وينحدر من أسرة عريقة مشهورة بالعلم والأدب، عاش بحر العلوم شاعراً ينقل بصوره الجمالية كل ما يقع في حواسه، وتجربته تثري من اتصاله ببيئته فنجد الشاعر اشبه بالمصور يستمد صوره من واقع بيئته المتنوع. ونحن في بحثنا هذا نحاول أن نرصد أهم المصادر
... Show More