The evacuated tube solar collector ETC is studied intensively and extensively by experimental and
theoretical works, in order to investigate its performance and enhancement of heat transfer, for Baghdad climate
from April 2011 till the end of March 2012. Experimental work is carried out on a well instrumented collector
consists of 16 evacuated tubes of aspect ratio 38.6 and thermally insulated tank of volume 112L. The relation
between convective heat transfer and natural circulation inside the tube is estimated, collector efficiency, effect of
tube tilt angles, incidence angle modifier, The solar heating system is investigated under different loads pattern (i.e
closed and open flow) to evaluate the heat loss coefficient from tank and tubes, test the collector with various
aspect ratios (32.9 and 27.2). The enhancement in collector performance is studied by using two reflectors (Flat
Plate and Curved Plate) and nanofluid (Water-AL2O3).Theoretical work is run by software (Fluent 6.3), to compute
the velocity and temperature profiles within the tube, for different tube diameters, effect of tube junction angle and
stagnant region in the bottom of the evacuated tube. The experimental results shows that the heat loss coefficient
for tube is W/m2.K and for tank is W/m2.K, the maximum collector temperature is 79°C in winter and
99°C in summer, while that belong to nanofluid collector is 99°C in winter. The best tilted angle (optimum) of
evacuated tube is 41° annually. The collector efficiency increased when using nanofluid of (1, 0.6, 0.3)% volume
fraction as(28.4, 6.8, 0.6)% respectively. The efficiency decreases as (33, 62)% when decreasing tube aspect ratio
from 38.6% to 32.9% and 27.2% respectively. An increase of (16.9 and 7.08)% in collector efficiency is obtained
when using curved and flat plate reflectors respectively. From simulation the best junction angle of the tank is
22.5°. The stagnant region is influenced with changing heat flux, tilted angle and aspect ratio.
In his life, a person engages in different types of verbal and actual dispositions that result in various effects, some of which are necessary and not valid, such as selling, and some are not necessary for one of the two contracting parties, such as a mortgage or both, such as lending and agency. However, there are some actions that are sometimes necessary and not necessary at other times, such as a gift that indicates in its simplest sense. Owning money for another without compensation, it is one of the doors of benevolence and benevolence, and it is one of the attributes of perfection with which God, may He be glorified and exalted be He, described Himself. - And if this analogy is the difference - and distanced himself from greed, the
... Show MoreThe principle of rights and duties is part of the reform project of the Commander of the Faithful Ali ibn Abi Talib, to build a state of institutions whose foundations have been built on Quranic rules, a prophetic biography, and his diligence in doing so in accordance with the requirements of interests and evil, and his certainty in determining the most important and important, and research analytical study of speeches Imam Ali and his career, in this study (the principle of rights and duties) of the ruler and the parish because of their role in the reform process, which depends on the demolition and construction together, as it is the responsibility of the ruler to demolish all constructed corrupt and contrary to the principles of Islam
... Show MoreMost of the world is seeking attention to the agricultural sector, which occupies a distinguished economic center, including Iraq, it is no wonder that the focus is on this sector, especially in developing countries. Descriptive analysis of the sample tables of wheat and barley crops in Iraq showed that adherence to the principles and rules of total quality, including modern irrigation methods (irrigated) has a significant impact in increasing productivity, reducing costs and improving quality compared to traditional irrigation methods, so it became necessary to take agricultural economic units All procedures and means that will help in the application of the rules of total quality to promote the reality of wheat and barley cultivation in I
... Show MoreThis work aimed to estimate the frequency of mitochondrial inborn errors of metabolism (MIEMs) in patients presenting with family history and IEM-picture who referred for advance IEM assay in Mosul province and Kurdistan region. This study was observational study conducted on 364 cases referred from different general /or private pediatric clinics with unexplained sign and symptoms and suspension of mitochondrial dysfunction. The study included 364 children with an age ranging from 1 month to 1 year. Started from January 2018 to January 2020. All patients referred with their full history review, notes about their clinical examination, and laboratory investigations including blood ammonia, serum lactate/ pyruvate, arterial blood gases. In
... Show MoreOnomatopoeia has always been a functional poetic device which enjoys a high sound significance in the poetry of many languages. In modern English and Arabic poetry alike, it proves to be vital and useful at different levels: musical, thematic and at the level of meaning. Still, the cultural difference looms large over the ways it is employed by the poets of each. The present paper investigates the employment of onomatopoeia in the poetry of D. H. Lawrence (1885-1930) and Badr Shakir al-Sayyab (1926-1964) who are chosen due to the importance they enjoy in modern English and Arabic poetry and the richness of their poems in onomatopoeias. The conclusions reached at are in a sense related to cultural differences which govern the use of onomato
... Show MoreIn this study, the radon gas concentration as well as the annual effective dose in leaves of the Malvasylvestris (Khabbaz) plant used in the traditional treatment and as food in Iraq, for this, it is necessary to evaluate the concentrations radon gas, which were measured using solid state nuclear track detectors (SSNTDs) CR-39 technique. The concentration and annual effective dose in samples were collected from Baghdad city ranged from minimum to maximum value 15.815 , 0.498 , 54.445 , 1.717 respectively, while the values of concentration and annual effective dose in a sample collected from Karbala are 15.297 ,0.482 . These values of concentration and annual effective dose less were compared with th
... Show MoreHemogloin (Hb) and serum ferritin levels are used to assess anemia in pregnancy. Some studies referred to the influence of maternal age, body mass index (BMI) and parity on Hb and serum ferritin levels. The study aimed to examine the possible association of maternal Hb and serum ferritin with maternal age, parity, and BMI in a sample of pregnant women in Baghdad.
Ninety healthy pregnant women, grouped in three equal groups according to the pregnancy trimester, and thirty apparently healthy non-pregnant women from Baghdad were enrolled in this observational study. Blood and serum samples were obtained for the estimation of Hb and serum ferritin levels.
The pooled data of participants showed a n
... Show MoreBackgrround:: Cholera is gastroenteritis caused by enterotoxin producing Vibrio cholera. Cholera is predominantly a waterborne disease especially in countries with inadequate sanitation. Several rapid methods have been developed and used to detect V. cholerae serotypes directly from stools.
Objjecttiives:: to evaluate a rapid and accurate method for the diagnosis of cholera caused by V. cholerae O1 and O139 serogroups d to find the incidence of sporadic cases of cholera in Baghdad.
Metthods:: Sixty four stool samples were collected from four hospitals in Baghdad. The age of patients ranging from two months to 12 years, 26 were females and 38 males. Immunochromatographic visual test for qualitative detection of O1 and /or O139 serog