The current study presents an experimental investigation of heat transfer and flow characteristic for subcooled flow boiling of deionized water in the microchannel heat sink. The test section consisted of a single microchannel having 300μm wide nominal dimensions and 300μm height (hydraulic diameter of 300μm). The test section formed of oxygen-free copper with 72mm length and 12mm width. Experimental operation conditions spanned the heat flux (78-800) kW/m2, mass flux (1700 and 2100) kg/m2.s at 31˚C subcooled inlet temperature. The boiling heat transfer coefficient is measured and compared with existing correlations. Also, the experimental pressure drop is measured and compared with microscale pressure drop correlations. The results showed that higher mass flux leads to higher boiling heat transfer coefficient, and the dominant mechanism is convective boiling. Also, the experimental pressure drop decrease with increasing heat flux in a single-phase region while it increases in a two-phase region. Comparing the experimental results in the experimental condition range, showed that an existing correlation provides a satisfactory prediction of heat transfer coefficient and pressure drop.
Diabetes mellitus can be defined as a metabolic disorder disease .Complication of diabetes are due to diabetic nephropathy .This study was done in vitro to study the effect of different concentrations of erlotinib inhibitor ( tyrosine kinase inhibitor) on electrolyte levels (MgâºÂ²,CaâºÂ²,Naâº) in sera of Iraqi patients with newly diagnosis type2 diabetes and diabetic nephropathy in addition to find the best percentage inhibition for utilizing different concentrations from erlotinib (6.97x10â»â·, 9.30x10â»â· ,1.16x10â»â¶,1.39x10â»â¶ ,1.62x10â»âµ )molar on electrolyte levels . This study was conducted in The National Diabetes Ce
... Show MoreThe crystal structure and unit cell dimensions of the (S03) compound have been determined by employing the principles of crystallography.
The X-Ray diffraction spectra of (Sb203) which recorded as a function of different annealing temperatures (100,150,200 and
250)±5c and for durations (0.5 hr,
0
1hr, l.Shr and 2hr), showed a
noticeable improvement, a decreasing in the unit cell dimensions and
an increasing in the number of diffraction spectra.
Indexing of diffraction spectra and refinement of unit cell
dimensions showed that the compound (Sb203) which is a
... Show MoreScorpions and spiders belong to the class Arachnida in phylum Arthropoda. Scorpions are easily distinguished by median eyes on obvious the center of the carapace and have one pair, and lateral eyes have 2-8 in some species. Scorpions do not have good eyesight so the median eyes have always been simple and they are more sensitive than the lateral pairs. They have anterior median eyes (AME) with narrow field of view and pairs of lateral eyes (LE) with more sensitivity and response to light. Family Buthidae have 2-6 lateral eyes in Compsobuthus Mesobuthus, Hottentotta, while Vaejovidae, Chactidae and Chaerilidae have 2 pairs of lateral eyes. In addition, 3 pairs are found in Orthochirus and Androctonus. Spiders have six eyes in family Pholicid
... Show MoreEntropy generation was studied for new type of heat exchanger (shell and double concentric tubes heat exchanger). Parameters of hot oil flow rate, temperature of inlet hot oil and pressure drop were investigated with the concept of entropy generation. The results showed that the value of entropy generation increased with increasing the flow rate of hot oil and when cold water flow rate was doubled from 20 to 40 l/min, these values were larger. On the other hand, entropy generation increased with increasing the hot oil inlet temperature at a certain flow rate of hot oil. Furthermore, at a certain hot oil inlet temperature, the entropy generation increased with the pressure drop at different hot oil inlet flow rates. Final
... Show MoreThe concept of entransy dissipation was determined for new type of heat exchanger (shell and double concentric tubes heat exchanger). Three parameters, hot oil flow rate, temperature of inlet hot oil and pressure drop of system were investigated with this concept (entransy dissipation). The results showed that the value of entransy dissipation of oil and of system which represents the summation of entransy dissipation of both oil and water increased with increasing the flow rate of hot oil and these values were larger when cold water flow rate was doubled. Also they were increased with increasing the hot oil inlet temperature at a certain flow rate of hot oil. Furthermore, the pressure drops for hot oil in both shell side and inner tubes
... Show MoreRoad-side dust samples were collected during August in 2020 from selected areas of, Al-Rusafa, Baghdad, Iraq. A sedimentological and mineralogical analysis of street dust was conducted. Three areas were selected to study street dusts which are Al-Baladitat, Al-Obaidi and Ziona. The laboratory analyses were done in the Department of Geology, College of Science, University of Baghdad. The heavy metal contents were determined in the roadside dust using XRF Method. It was found that the dust is of muddy texture, and is believed to be transmitted with the various storms blowing on Baghdad or by the wheels of Cars. The results of mineralogical investigation revealed that the dust samples composed of quartz, feldspar, calcite, gypsum and s
... Show Moreresearch objectives to:
1. identify the social, economic and cultural factors affecting consumption.
2. detect the consumption culture among the population in the city of Erbil.
3. Identify the GATT consumer protection and rights.
The most important results:
1. that there is variation in the answers of respondents about keep up with modernity in the basic consumption (necessary), it swallowed the proportion of yes answers about keep up with modernity in food consumption (72%), and is an indication of growing consumer awareness of the individual in the side of nutrition. The clothing on the side of the proportion of yes answers amounted to (85%), in the health field note that the percentage of yes answers (83%), who are abr
The importance of the research comes from dealing with the problem of lack of traffic awareness, which causes accidents and the occurrence of human and material losses, and the research aims to study the role of satellite channels in forming traffic awareness among the public, and a sample was chosen from Baghdad consisting of (280) individuals, male and female, and used the questionnaire tool. To obtain the data, which included several questions, the results were analyzed statistically and several results were reached, the most important of which is that there is an interest among the public in following traffic programs at a rate of one to two hours to receive information through traffic programs and to identify and apply gener
... Show MoreDue to its safety, low cost, real-time nature, and widespread availability, ultrasound has been employed as a diagnostic technique for numerous intraocular disorders. Unfortunately, speckle artifact that depends on the tissue is seen in ultrasound imaging. In this study, we present a technique for lowering speckle noise and enhancing ultrasound images to enhance human diagnostic performance. This technique combines the undecimated wavelet transform (UDWT) with a wavelet coefficient mapping function, which was utilized to improve the contrast of the denoised images acquired from the first component after the noise was removed using the UDWT. This technique can be used to enhance the visual quality of medical photographs as well as to enha
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