The Nano materials play a very important role in the heat transfer enhancement. An experimental investigation has been done to understand the behaviors of nano and micro materials on critical heat flux. Pool boiling experiments have used for several concentrations of nano and micro particles on a 0.4 mm diameter nickel chrome (Ni-Cr) wire heater which is heated electrically at atmospheric pressure. Zinc oxide(ZnO) and silica(SiO2) were used as a nano and micro fluids with concentrations (0.01,0.05,0.1,0.3,0.5,1 g/L), a marked enhancement in CHF have been shown in the results for nano and micro fluids for different concentrations compared to distilled water. The deposition of the nano particles on the heater surface was the reason behind the enhancement of the wettability of the surface which will increase the CHF, this nano particles deposition will form a porous layer and the mechanism of the formation of this layers is that as vapor bubbles grow, the evaporating liquid in the micro layer leaves behind Nano particles which then will be concentrated at the base of the bubble to form this pours layer. The higher wettability can produce CHF enhancement, the enhancement ratio of Nano fluid is observed to be higher than that of micro fluid, the optimum enhancement ratios of nano fluid is (1 g/l) which observed to be 9.2 % for ZnO and 8.7% for Sio2, and also (1 g/l) for micro fluid which observed to be 8.1%for ZnO and 7.4%for SiO2.
At present, numerous novel chemical compounds face challenges related to their limited solubility in aqueous environments. These compounds are classified under the Biopharmaceutical Classification System (BCS) as either class II or class IV substances. Different carriers were used to increase their solubility. Candesartan cilexetil (CC) is one of the most widely used antihypertensive drugs, which belongs to class II drugs. The aim of this research was to enhance the solubility and dissolution rate of CC through a complexation approach involving β-cyclodextrin and its derivatives, specifically hydroxypropyl beta cyclodextrin (HP-β-CD), methyl beta cyclodextrin (M-β-CD), and sulfonyl ether beta-cyclodextrin (SBE-β-CD), serving as
... Show MoreDirectional Compact Geographic Forwarding (DCGF) routing protocol promises a minimal overhead generation by utilizing a smart antenna and Quality of Service (QoS) aware aggregation. However, DCGF was tested only in the attack-free scenario without involving the security elements. Therefore, an investigation was conducted to examine the routing protocol algorithm whether it is secure against attack-based networks in the presence of Denial-of-Service (DoS) attack. This analysis on DoS attack was carried out using a single optimal attacker, A1, to investigate the impact of DoS attack on DCGF in a communication link. The study showed that DCGF does not perform efficiently in terms of packet delivery ratio and energy consumption even on a sin
... Show MoreThis research aims to analyze the intellectual and civilizational regression that afflicted Iraqi and Arab society due to political and religious tyranny and internal conflicts, which was reflected in the deterioration of human rights values and the absence of equality and justice in dealing with the other religiously, which affected the reluctance of members of religious groups to interact with their national societies and then migrate to Outside, which contributed to a double loss, in terms of the loss of these societies by productive and effective national competencies, and in terms of distorting the image of Islam. The research stressed that the first treatments of this phenomenon are the consolidation of the values of citize
... Show MoreThis study included the fabrication of compound (Tl2-xHgxBa2-ySryCa2Cu3O10+δ) in a manner solid state and under hydrostatic pressure ( 8 ton/cm2) and temperature annealing(850°C), and determine the effect of the laser on the structural and electrical properties elements in the compound, and various concentrations of x where (x= 0.1,0.2,0.3 ). Observed by testing the XRD The best ratio of compensation for x is 0.2 as the value of a = b = 5.3899 (A °), c = 36.21 (A °) show that the installation of four-wheel-based type and that the best temperature shift is TC= 142 K .When you shine a CO2 laser o
... Show MoreThis research is considered one of the important researches in Maysan Governorate, as it focuses on the construction of helicopter airport project in the oil fields of the Maysan Oil Company, where the oil general companies in Maysan Governorate suffer from the cost of transporting the foreign engineering experts and the governing equipment of sustaining oil industry from Iraq's international airports to oil fields and vice versa. Private international transport companies transport foreign engineering from the oil fields to Iraqi airports and vice versa, and other international security companies take action to provide protection for foreign engineering experts during transportation. Hence, this process is very costly.
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... Show MoreThis research aims to investigate the thermal performance of different thermal composite insulators, wrapped around a closed-loop copper pipe (CLP). To achieve this aim a system was designed and manufactured. It is consisted of closed water tank insulated by Rock Wool, and supplied with two electric heaters, two thermostat, a flow meter, a water pump, digital temperature scales, and four series of (CLP).
Six insulators were prepared namely; composites of Impregnated Fiberglass with Elastoclad and foaming Rubber (FER), Impregnated Fiberglass with Elastoclad resin and Polymeric Membrane (FEM), Impregnated Fiberglass with Polyurethane thermoset resin and Foaming Rubber (FUR), Impregnated Fiberglass with Polyurethane thermoset resin and P
Cadmium sulfide photodetector was fabricated. The CdS nano
powder has been prepared by a chemical method and deposited as a
thin film on both silicon and porous p- type silicon substrates by spin
coating technique. Structural, morphological, optical and electrical
properties of the prepared CdS nano powder are studied. The X-ray
analysis shows that the obtained powder is CdS with predominantly
hexagonal phase. The Hall measurements show that the nano powder
is n-type with carrier concentration of about (-5.4×1010) cm-3. The
response time of fabricated detector was measured by illuminating
the sample with visible radiation and its value was 5.25 msec. The
specific detectivity of the fabricated det
The research seeks to identify the impact of fraud detection skills in the settlement of compensatory claims for the fire and accident insurance portfolio and the reflection of these skills in preventing and reducing the payment of undue compensation to some who seek profit and enrichment at the expense of the insurance contract. And compensatory claims in the portfolio of fire and accident insurance in the two research companies, which show the effect and positive return of the detection skills and settlement of the compensation on the amount of actual compensation against the claims inflated by some of the insured, The research sample consisted of (70) respondents from a community size (85) individuals between the director and assistan
... Show MoreThe importance of the construction sector and its Great role in the provision of services and infrastructure, reduce poverty, improve living conditions and improve the economic situation in the country, impose attention to the way in which the projects implemented for its improvement and to get successful projects. The objective of this research was to determine the criteria for success as well as critical success and failure factors that have a significant impact on project success. A selected 75 engineer (department managers, project managers and engineers) are asked to fill the questionnaire form, Sixty-seven valid questionnaire forms were analyzed statistically to get search results, which were as follows : Twe
... Show MoreAbstract
In the present work, thermal diffusivity and heat capacity measurements have been investigated in temperature range between RT and 1473 K for different duplex stainless steel supplied by Outokumpu Stainless AB, Sweden. The purpose of this study is to get a reliable thermophysical data of these alloys and to study the effect of microstructure on the thermal diffusivity and heat capacity value. Results show the ferrite content in the duplex stainless steel increased with temperature at equilibrium state. On the other hand, ferrite content increased with increasing Cr/Ni ratio and there is no significant effect of ferrite content on the thermal diffusivity value at room temperature. Furthermore, the heat capacity of all sam
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