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%.
Old New York was Wharton's term to describe this wealthy and elite class at the top of
the developing city's social hierarchy, a society which was utterly intent on maintaining its
own rigid stability. Even though, the roles of women in American society changed drastically
from 1820’s to 1860’s due to the civil war and such a progression was due in part to the
revolutionary thoughts. Women started taking their right to speak up openly and frankly and
become more like men. The role of many women had changed from being homemaker to
being able to provide for the family by either getting a job or start to be allowed to have a
voice. They had important roles not only in helping the family, but in sharing to rebuild th
The common history of Latin America countries may contribute significantly to determine the initial beginnings of these States since the current borders are a reflection and drawing of the borders of Antarctica according to the divisions determined by the behavior of the Portuguese and Spanish colonialism as well as what the Pope originally called for in order to divide property between Spain and Portugal. A later change took place especially after the independence in the first quarter of the 19th century for the majority of those States which is something that imposed special consideration in the analysis and description of each of these States. There are constants and variables in this case where all the States share constants, while t
... Show MoreThe story of Peter Pan is considered one of the immortal tales that has been read and watched over many generations, and many of the events of the story have been changed over time to suit the time in which it will be read, and this is what will be discussed in this paper in addition to identifying the writer‟s life and the extent influence on Peter Pan. Time in the story of Peter Pan is particularly important because the story changes its events during that time in proportion to the era in which it is in, as there have been many changes in all events and characters to suit the reader. Through this paper, the researcher will come up with the life of the author and how his life affected Peter Pan‟s story, then a small summary of the stor
... Show More That analytical procedures are of analytical tools important because it gives assurance to the auditor-free financial statements of the economic units replace the audit of cases offraud and errors and distortions, and thereby to increase the effectiveness of the audit process and confirm the possibility oftrust and reliance on the financial statements that Adfgaha auditor.
Inspite of identify evidence of proof necessary to enhance the auditor's opinion the results reached in the audit p
Background: Recurrent laryngeal nerve injury is
an important post-thyroidectomy complication for
which different modalities of treatment were
practiced to lower its incidence.
Objectives: To estimate the incidence of
recurrent laryngeal nerve injury in thyroid surgeries
in relation to type of surgery, type of gland diseases
& nerve identification.
Methods: Different types of goiters prepared
preoperatively by indirect laryngoscopy, operated
upon with different types of surgeries, postoperative
direct laryngoscopy by the anaesthetist were done
and indirect laryngoscopy done as needed.
Results: Of of 200 patients, the overall incidence
of recurrent laryngeal nerve injury was 9
Patients (4.5%
The study tries to answer several questions posed by the subject, one of the important: How the Internet promotes rumor? And what are the most Internet applications that promote rumor? And the practical ways to reduce these negative? Using the process of in vestige and reading theoretical heritage available in this field, and inferred the numbers and statistics marked the uses of the Internet and its applications over recent years, and the characteristics of each these tools in the field of collection, processing, and dissemination of information
Toxoplasma gondii is an obligate intracellular protozoan parasite; it spreads via the circulatory system during infection and causes chronic infection in various organs. Toxoplasmosis affects nearly one third of people worldwide, especially immunocompromised people. This study aimed to determine the effect of toxoplasmosis on renal function in hemodialysis patients. Overall 300 patients referred to the Medical City, Al-Karama General Hospital, Baghdad, Iraq were enrolled from 2021 to 2022. All serum samples were tested for T. gondii immunoglobulins (IgG and IgM) antibodies, urea and creatinine levels. In patients undergoing hemodialysis, the results revealed a high positivity percentage for anti-Toxoplasma IgG. In hemodialysis patients infe
... Show MoreThe functional properties of the defatted powder and protein isolate of germinated mung bean seeds were studied and the estimation of the amino acids was carried out. The results showed a significant increase in the values of the amino acids leucine, lysine, phenylalanine and valine. The results of studying the functional properties of the protein isolate and defatted powder showed that there were significant differences between the sample The defatted and protein isolate, if the water absorption capacity of the defatted mung powder was 2.5% water/gm protein and the water absorption capacity of the protein isolate was 3%ml water/g protein, the fat binding capacity of the defatted powder was 0.3 ml fat/g protein and the isolate The ratio was
... Show MoreThe study aimed to get acquainted with kindergarten teachers in the development of
emotional intelligence in children, To achieve this a study too, which consisted of 40 items,
within four areas was condncted: (managing emotions, emotional knowledge, empathy, social
networking) The study tool was applied to the sample amounting (200) teachers of the
kindergarten teachers in the province of Jerash and after analyzing the results statistically
using arithmetic averages standard deviations and variance analysis quartet the following
results were reached :
- presence of statistically significant differences at the level of (α =0,05) is attributable to the
impact of the educational level in the areas of empathy and so