The present study involves experimental analysis of the modified Closed Wet Cooling Tower (CWCT) based on first and second law of thermodynamics, to gain a deeper knowledge in this important field of engineering in Iraq. For this purpose, a prototype of CWCT optimized by added packing under a heat exchanger was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the towers thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of air measured at intermediate points of the heat exchanger and packing. Exergy of water and air were calculated by applying the exergy destruction method on the cooling tower. Experimental results showed a significant performance improvement when using packing on the CWCT. It can be observed that the thermal efficiency for the CWCT with packing under a heat exchanger and CWCT with packing above the heat exchanger are approximately 40% and 25% higher than that of the CWCT without packing respectively. As another part of the experiment results, it is indicated that the exergy destruction is directly proportional to air flow rate, cooling water flow rate, inlet cooling water flow rate and inlet Air Wet Bulb Temperature (AWBT) whereas, it is inversely proportional with spray water flow rate. In comparison with the cooling capacity of the tower, it was found that the exergy destruction approximately less than 20%. Exergy efficiency behavior is inversely proportional with the behavior of the exergy destruction. Empirical correlations are obtained to predict water film heat transfer coefficient and air-water mass transfer coefficient considering the influences of operational parameters.
In recent years, the attention of the international community and intergovernmental and non-governmental organizations has grown into a new dimension of population displacement, called displacement within the country as a result of conflicts and the expansion of tacit groups, using sentences to describe such conflicts as "identity-based conflict", "ethnic conflict" "Sectarian conflict", in an attempt to determine the nature and characterization of those conflicts. In such conflict-stricken conditions, the value of a citizen - a person not directly involved in the conflict - is measured by the potential gains that that person has made to the conflicting parties, as civilians have been indirect victims of military operations, Favor
... Show Moreيهدف البحث الى دراسة وتحليل التمويل الأخضر كأحد المفاهيم الاساسية والحديثة في عالم الاعمال والاقتصاد العالمي وخاصة بعد الازمات والتحديات التي توالت على العالم نتيجة الكوارث الطبيعة وتغييرات المناخ والضغوطات على الموارد الطبيعية والتي أدت الى احداث اثرا كبيرا في اقتصاديات الكثير من الدول ، مما اضطرت الى إعادة النظر في مشاريعها وانشطتها الاستثمارية بما يوائم وطبيعة البيئة ومتغيراتها ، لذا تحتم اختيار لمثل
... Show MoreA characteristic study of a passively Q-switched diode pumped solid state laser system is presented in this work. For laser a comparison study for the theoretically calculated results with a simulation results using a software which calculates the Q-switched solid state laser parameters was such as energy, peak power and pulse width were performed. There was a good agreement between our theoretical calculations and the simulation values.
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A field study was conducted at the college of Agriculture, Baghdad University-Jadiriyah to investigate the effect of adding potassium fertilizer and organic nutrient (Reef Amirich) on the population density of two sucking pests of cucumber, cotton whitefly, Bemisia tabaci and onion thrips, Thrips tabaci during the spring season/2016. Results indicated that potassium sulphate (50, 100 and 150 kg/ha) and organic nutrient (0.8 and 1.6ml/l) reduced both the population density of B. tabaci and T. tabaci nymphs depending on the fertilizer level of the user, the treatment 150 kg/ha for the potassium fertilizer and 1.6 ml/L for organic nutrient was the highest among others when minimized density of nymphs by 1.62 nymphs of B. tabaci/disk leaf and 0
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There is a global shortage of health care providers needed to address all levels of primary and specialty care. The recent COVID-19 pandemic also highlights the importance and added value of health professionals with specialty training in infectious diseases. In the United States, advanced practice providers (APPs) are being engaged to meet the expanding demand for generalist and specialist patient care. The history and development of advanced practice registered nurses (APRNs) and physician assistants (PAs), are discussed as collaborative healthcare providers to promote better understanding of the ways they can be incorporated into a healthcare system. An example of how APPs are utilized to provide both inpatient and outpatient
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