This paper presents an experimental study of cooling photovoltaic (PV) panels using evaporative cooling. Underground (geothermal energy) water used to extract heat from it during cooling and cleaning of PV panels. An experimental test rig was constructed and tested under hot and dusty climate conditions in Baghdad. An active cooling system was used with auxiliary an underground water tank to provide cold water as a coolant over both PV surfaces to reduce its temperature. The cellulose pad has been arranged on the back surface and sprays cooling on the front side. Two identical PV panels modules used: without cooling and evaporative water cooling. The experiments are comprised of four cases: Case (I): backside cooling, Case (II): front and back cooling (pump supply water every 35 minutes), Case (III): cooling both sides using Arduino controller. Water cooling pump operation depending on the panel temperatures (temperature sensors were installed on the front of the panel), Case (IV): Repeating case III with different water flow rates. Experimental results showed that the average reduction in module temperatures was 4, 8,12.2 and 12.6 ⁰C respectively by Case (I), (II), (III) and (IV) with respect to a non-cooling module. Using evaporative water cooling achieved a total improvement of 1.74%, 2.8%, 15.8%, and 16% in the conversion efficiency of the panel by the Case (I), (II), (III) and (IV) respectively when compared to a non-cooling module.
اثناء تفاعل الديزنة تكونت صبغة أزو جديدة عن طريق تفاعل 3-امينوفينول مع 2,4,6-ثلاثي هيدروكسي اسيتوفينون . ثم تم تفاعل هذا الليكاند مع بعض ايونات العناصر الكروم والحديد الروديوم والروثينيوم بتكفؤهم الثلاثي والكوبلت الثنائي والموليبدينوم سداسي التكافؤ مكونة معقدات فلزية مختلفة بأشكال هندسية متعددة. تم ملاحظة تناسق مجموعة الازو مع ايونات العناصر من خلال ملاحظة ظهور حزم امتصاص الفلز مع النتروجين والاوكسجين ب
... Show MoreResearchers have shown considerable interest in the idea of organizational climate because of its crucial role in school administration and all school operations. Hence, enhancing it is regarded as a primary duty of school principals, as they bear direct accountability for overseeing the school and its entire operations. Total quality management is a primary method that allows the school administrator to effectively handle administrative tasks with the goal of meeting the needs of instructors, students, staff members, and the community. The significance of the research rests in its attempt to shed light on the value of both organizational climate and total quality management among high school principals. The research seeks to determine the
... Show MoreA total of 48 experiments were conducted to investigate the impact of slit weir dimensions and locations on the maximum scour depth and scour area created upstream. The slit weir model was a 110 mm slit opening, and it was installed at the end of the working section in a laboratory flume. The flume was 10.0 m long, 30 cm wide, 30 cm deep, and almost middle. It includes a 2 m working section with a mobile bed with 110 mm in thickness. In the mobile bed, two types of nonuniform sand (with a geometric standard deviation of 1.58 and 1.6) were tested separately. The weir dimensions and location were changed with flow rates. Then dimensions of the slit weir were changed from 60 x 110 mm to 60 x 70 mm (width x height), while th
... Show MoreIn dieser Kurzgeschichte werden die Züge der Trümmerliteratur präzis dargestellt. Die wurde von Heinrich Böll im Jahr 1958 geschrieben. In der vorliegenden Arbeit konzentriere ich mich auf vielfältige Stoffe in Bezug auf die Lage nach dem Zweiten Weltkrieg. So gab ich dieser Arbeit einen besonderen Titel, der die Dimensionen dieser Kurzgeschichte heißt. Ich meine hier, die profunde Interpretation dieses Werkes, denn ich fand zwar hinter einigen Wörtern eine ganze Geschichte, die uns der Erzähler dadurch zeigen wollte.
So teilte ich diese Wörter (Grab, Schatten, Last, Schrei) als Dimensionen, von denen diese Arbeit umgekreist wird.
Diese Arbeit besteht aus vier Kapiteln, die aufeinander aufgebaut sind. Im ersten K
... Show Moresynthesis, Composition, Spectral, Geometry and Antibacterial Applications ofMn(||),Ni(||),Co(||),Cu(||) and Hg(||) schiff Base complexes of N2O2 mixed donor with 1,10-phenanthroline
Background: The present study aimed to assess the distribution, prevalence, severity of malocclusion in Baghdad governorate in relation to gender and residency Materials and Methods: A multi-stage stratified sampling technique was used in this investigation to make the sample a representative of target population. The sample consisted of 2700 (1349 males and 1351 females) intermediate school students aged 13 years representing 3% of the total target population. A questionnaire was used to determine the perception of occlusion and orthodontic treatment demand of the students and the assessment procedures for occlusal features by direct intraoral measurement using veriner and an instrument to measure the rotated and displaced teeth. Results a
... Show Moret:
The most famous thing a person does is talk. He loves and hates, and continues with it confirming relationships, and with it, too, comes out of disbelief into faith. Marry a word and separate with a word. He reaches the top of the heavens with a kind word, with which he will gain the pleasure of God, and the Lord of a word that the servant speaks to which God writes with our pleasure or throws him on his face in the fire. Emotions are inflamed, the United Nations is intensified with a word, and relations between states and war continue with a word.
What comes out of a person’s mouth is a translator that expresses the repository of his conscience and reveals the place of his bed, for it is evidence of
... Show MoreIn the past infectious diseases affected the quality of lifestyle during home confinement. The study conducted examines the influence of home confinement during the COVID-19 pandemic outbreak on lifestyle, mental wellbeing, nutritional status, and sleeping pattern.
An online multicategorical questionnaire was distributed to collect demographic information combined with the following tools: Food Frequency Questionnaire (FFQ), International Physical Activity Questionnaire (IPAQ), WHO-5 wellbeing score, and Pittsburgh Sleep Quality Index (PSQI). A snowball non-discriminate sampling procedure was
Communicative-based textbooks are developed and disseminated throughout the country.
However, it is difficult for teachers who themselves have learnt English through the traditional
approaches to suddenly be familiar with CLT (Communicative Language Teaching) principles
and teach communicatively. Therefore, many teachers remain somewhat confused about what
exactly CLT is and others familiar with CLT but unable to achieve communicative classroom
teaching. Consequently, those teachers need to be introduced to the CLT principles and they need
training in how to put CLT principles into practice. Accordingly, this study aims to find out the
effect of combining video lectures and Kolb experiential learning on EFL student-t