A design for a photovoltaic-thermal (PVT) assembly with a water-cooled heat sink was planned, constructed, and experimentally evaluated in the climatic conditions of the southern region of Iraq during the summertime. The water-cooled heat sink was applied to thermally manage the PV cells, in order to boost the electrical output of the PVT system. A set of temperature sensors was installed to monitor the water intake, exit, and cell temperatures. The climatic parameters including the wind velocity, atmospheric pressure, and solar irradiation were also monitored on a daily basis. The effects of solar irradiation on the average PV temperature, electrical power, and overall electrical-thermal efficiency were investigated. The findings indicate that the PV temperature would increase from 65 to 73 °C, when the solar irradiation increases from 500 to 960 W/m2, with and without cooling, respectively. Meanwhile, the output power increased from 35 to 55 W when the solar irradiation increased from 500 to 960 W/m2 during the daytime. The impact of varying the mass flow rate of cooling water in the range of 4 to 16 L/min was also examined, and it was found that the cell temperature declines as the water flow increases in intensity throughout the daytime. The maximum cell temperature recorded for PV modules without cooling was in the middle of the day. The lowest cell temperature was also recorded in the middle of the day for a PVT solar system with 16 L/min of cooling water.
Nanoparticles of copper sulfide have been prepared by simple reaction between using copper nitrate with different concentrations ratio 0.1, 0.3, and 0.5 mM, thiourea by a simple chemical route. The prepared Nano powders have been deposited onto glass substrates by casting method at 60°C. The structure of the product Nano- films has been studied by x-ray diffraction, where the patterns showed that all the samples have a hexagonal structure of covellite copper sulfide with the average crystalline sizes 14.07- 16.51 nm. The morphology has been examined by atomic force microscopy, and field emission scan electron microscopy. The AFM images showed particles with almost spherical and rod shapes with average diameter sizes of 49.11- 90.64 nm.
... Show MoreBackground: Osteoarthritis (OA) currently seems
inevitable and unavoidable for a large swath of the
population .its etiology relates to a strong ,but
complex ,non mendelian genetic basis ,combined
with mechanical and metabolic factors that cause
molecular alterations the end results of which
affect the whole joint .Glucosamine and
chondrotin sulfate alone or in combination may be
of benefit to a subgroup of individuals who have
knee pain due to OA.
Glucosamine has been shown to alter cartiage turn
over in patients with OA undergoing physical
training
Aim of the study: To find the validity of
glucosamine chondrotin sulfate in treatment of
grade 1 and 2 OA.
Methods: the sample of 280 patients
The research deals with the problem of visual pollution, as it is one of the most important urban problems that cities suffer from. The concept of visual pollution has recently emerged to describe the deformation and degradation of the urban environment. Visual pollution is defined as any component of the surrounding environment that is inconsistent and not homogeneous with its natural and human components. The volume of visual pollution has doubled due to the non-compliance with the laws, regulations and controls set by the Municipality of Baghdad by the citizens, and to the weak municipal role that the municipality plays in implementing these laws. Therefore, it has become necessary to know the manifestations of visual pollution and th
... Show MoreOver the course of six decades, Iraq exposed to many events that have affected the Iraqi people from the social, physical and mental aspects. In this study, two groups of people (2369), from Iraq (G1) and the Michigan, United States (U.S) of America (G2) selected to compare the prevalence rate and effects of trauma factors such as mental illness (anxiety, depression and PTS), somatic diseases (heart disease, hypertension, and diabetes), substances abuse (illicit drugs, alcohol and tobacco), and chemicals pollution), and self-rated health among the two groups. The study results reveals a significant different between the two groups in the all indicators for trauma. The study conclude that Iraqi in U.S. (G2) suffer from factors completely dif
... Show MoreThe process of granting loans by banks is the confidence they give to their customers, but this trust should not be a cornerstone in granting loans even if granted these loans on the basis of sound banking should involve risks that may be exposed to the bank because of the failure of the client to meet The bank's financial obligations to the bank due to the unexpected economic conditions affecting the customers, which makes them in a state of faltering, which weaken the ability of banks to provide loans, which are the most important sources of revenue and profits, so the problem of non-performing loans is one of the main problems facing most of the banks Which impede the functioning of its work and the reasons that led to the agg
... Show MoreAbstract
This research’s goal is to restore and to revive the jurisprudence of Mother of Believers (Um alMuaamineen) “Um Salmah” "may God bless her", and to highlight her outstanding assimilation and understanding of religion and her conscious thought. The current research is a comparative scientific theoretical study represented in the comparison of jurisprudence of “Um Salamah” with Hadiths of fasting and pilgrimage rules as well as the duration mentioned in jurisprudence of for doctrines( 4 schools of thought )to identify these hadiths with the inclusion and discussion of their evidence.
The current research included two topics: the first one is to identify and introduce
... Show MoreImportance of the research:
The importance of any educational or scientific research through its intellectual arena of facts supply the individual and society, Supports Knowledge and Science Group, which raised will be locked in these topics in the future.
This research seeks to shed light on the image and the role of women and men in the books of the Arabic language in primary education (primary), To illustrate the negative effects of the phenomenon of sexism in textbooks, And its negative impact on emerging, And stay away as much as possible about the distinction between the sexes in the roles and qualities in textbooks traditional stereotypes and remove that put both sexes templates hinder the development of the individual and t