The thermal and electrical performance of different designs of air based hybrid photovoltaic/thermal collectors is investigated experimentally and theoretically. The circulating air is used to cool PV panels and to collect the absorbed energy to improve their performance. Four different collectors have been designed, manufactured and instrumented namely; double PV panels without cooling (model I), single duct double pass collector (model II), double duct single pass (model III), and single duct single pass (model IV) . Each collector consists of: channel duct, glass cover, axial fan to circulate air and two PV panel in parallel connection. The temperature of the upper and lower surfaces of PV panels, air temperature, air flow rate, air pressure drop, wind speed, solar radiation and ambient temperature were measured. The power produced by solar cells is measured also. A theoretical model has been developed for the collector model IV based on energy balance principle. The prediction of the thermal and hydraulic performance was obtained for the fourth model of PV/T collector by developing a Matlab computer program to solve the numerical model. The experimental results show that the combined efficiency of model III is higher than that of models II and IV. The pressure drop of model III is less than that of models I and IV, by (43.67% and 49%). The average percentage error between the theoretical and experimental results was 9.67%.
The problem of research is the need to find out the obstacles and difficulties facing women in accessing leadership positions at the University of Baghdad from their point of view. The importance of research comes from the importance of women in the university and their vital role in the development of society. The research objectives summarized the most important obstacles facing women Access to the leadership positions in the university and the relative weight of these obstacles as well as trying to identify differences in their view of these obstacles according to the variables of specialization (scientific, human) and the scientific title (Professor, Assistant Professor, Teacher, Assistant Lecturer). They were (144) university female
... Show MoreThis study deals with the role of compensation system in improving the quality of educational services (University of Halabja as a Model) also our problem was the following question ; What is the role of compensation system in its different dimensions in improving the quality of educational services? And what is the relationship and impact of using the dimensions of the compensation system to improve the quality of educational services? The hypothesis of the research included the correlation and the impacts between the compensation system and its combined variables in the quality of educational services. This was proved through a field study and the distribution of questionn
... Show More
The research included making a bibliography of the jurisprudential books available in the reference section of the central library at the University of Al-Mustansiriya. From this research, and I also saw that one of its objectives was to classify these books scientifically according to what was included in the Contemporary Islamic Fiqh Library of sections that were classified on its basis, according to what has settled in the custom of contemporary jurists, and according to the researcher’s view and his humble diligence, so the research was organized into an introduction and three topics. Each topic contained approximately five demands that included the sections of the contemporary jurisprudential lib
... Show MoreThe diversity of cultures is still the title of an Iraqi specificity that gave the society a diversity and this is reflected in the journalistic reality with the changing of the political system generate a new political and ideological life that differs from what is prevailed during the decades. However, its exacerbation of the degree of division is an additional duty for the press as a cultural platform and a knowledge bridge that contributes to the process of dialogue, addressing the differences, establishing a politically homogeneous structure through the state and socially by uniting all components of society and working to raise public awareness of the importance of national belonging to build a modern state. Cultural diversity is a
... Show MoreThis study was conducted at the Research Experimental Station of the College of Agricultural Engineering/University of Baghdad in the Al-Jadiriyah area during the autumn season of 2022. The study aimed to investigate the effect of phosphorus addition and zinc spraying on the nutrient content and root growth of the cabbage. The experiment included two factors: the first factor was phosphorus with four concentrations (P25%, P50%, P75%, and P100%) of the recommended complete fertilizer dose (135 kg P2O5 per hectare), and the second factor was zinc spraying with three concentrations (0, 30, and 60 mg.L-1) of zinc sulfate (ZnSO4). The results showe
The assessment of a river water’ quality is an essential procedure of monitor programs and is used to collect basic environmental data. The management of integrated water resources in a sustainable method is also necessary to allow future generations to meet their water needs. The main objective of this research is to assess the effect of the Diyala River on Tigris River water quality using Geographic Information System (GIS) technique. Water samples have been collected monthly from November 2017 to April 2018 from four selected locations in Tigris and Diyala Rivers using the grab sampling method. Fourteen parameters were studied which are Turbidity, pH, Dissolved Oxygen, Biological Oxygen Demand, Electrical Conductivi
... Show MoreBackground: Diabetes mellitus type 2 has been known for many years as the most common endocrine metabolic disorder that affect the oral cavity and cause many oral diseases including candidiasis. In this study, the incidence of Candida spp. in the saliva of controlled and uncontrolled diabetic patients were determined and compared with non diabetic group. Material and method: The sample consists of 200 subjects: 100 diabetic patients [57 (28.5%) uncontrolled diabetes, 43 (21.5%) controlled diabetes] and 100 (50%) non diabetic groups. Saliva samples was obtained from the subjects and cultured on selective media using appropriate microbiological method to observe the presence of Candida spp. Results: The results revealed a significant associat
... Show MoreVapor-liquid equilibrium data are presented for the binary systems n-hexane - 1-propanol, benzene - 1-propanol and n-hexane – benzene at 760 mm of mercury pressure. In addition ternary data are presented at selected compositions with respect to the 1-propanol in the 1-propanol, benzene, n-hexane system at 760 mmHg. The results indicate the relative volatility of n-hexane relative to benzene increases appreciably with addition of 1-propanol.
رافقت القسوة الانسان منذ القدم وكثيرا ما تم الخلط بينها وبين العنف لشدة التقارب بينهما , وهنا يحاول البحث ان يفصل بين كلا المفهومين ويتفرد بمفهوم القسوة, الذي سلط عليه الضوء في المسرح لأول مرة على يد الفرنسي(انطوان ارتو) في محاولة للكشف عن المعالجة الاخراجية التي قدمها المخرج العراقي(صميم حسب الله) لمفهوم القسوة في مسرحيته الموسومة (خريف) ويتضمن البحث نبذه (مفهوم القسوة في الفكر الانساني) وكذلك (الق
... Show MoreThe assessment of a river water’ quality is an essential procedure of monitor programs and isused to collect basic environmental data. The management of integrated water resources in asustainable method is also necessary to allow future generations to meet their water needs. Themain objective of this research is to assess the effect of the Diyala River on Tigris River waterquality using Geographic Information System (GIS) technique. Water samples have beencollected monthly from November 2017 to April 2018 from four selected locations in Tigris andDiyala Rivers using the grab sampling method. Fourteen parameters were studied which areTurbidity, pH, Dissolved Oxygen, Biological Oxygen Demand, Electrical Conductivity, TotalDissolved Solids,
... Show More