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.
Background: Debonding and fracture of artificial teeth from denture bases are common clinical problem, bonding of artificial teeth to heat cure acrylic and high impact heat cure acrylic denture base materials with autoclave processing method is not well known. The aim of this study was to evaluate the effect of autoclave processing method on shear bond of artificial teeth to heat cure denture base material and high impact heat cure denture base material. Materials and methods: Heat polymerized (Vertex) and high impact acrylic (Vertex) acrylic resins were used. Teeth were processed to each of the denture base materials after the application of different surface treatments. The sample (which consist of artificial tooth attached to the dentur
... Show MoreThe Mediating Role of Cobit 2019 in Managing the Relationship Between Qualitative Characteristics of Accounting Information and Information Asymmetry
Experimental investigations had been done in this research to demonstrate the effect of carbon fiber and Ceramic fillers contents on the tribological behaviour of (15% volume fraction) carbon-epoxy composite system under varying volume fraction, load, time and sliding distance. The wear resistance were investigated according to ASTM G99-05standard using pin on disc machine to present the composite tribological behaviour. The influence of three ceramic fillers, granite, perlite and calcium carbonate (CaCO3), on the wear of the carbon fabric reinforced epoxy composites under dry sliding conditions has been investigated. The effect of variants in volume fraction, applied load, time and sliding distance on the wear behaviour of po
... Show MoreTillage tools are subject to friction and low-stress abrasive wear processes with the potential deterioration of the desired soil quality, loss of mechanical weed efficacy, and downtime for replacing worn tools. Limited experimental methods exist to quantify investigate the effect of wear-resistant coatings on shape parameters of soil-engaging tools. ASTM standard sand/rubber wheel abrasion and pin-on-disk tests are not able to simulate wear characteristics of the complex shape of the tillage tools. Even though the tribology of tillage tools can be realistic from field tests, tillage wear tests under field conditions are expensive and often challenging to generate repeatable engineeri
The aim of this study is to investigate the antibacterial capabilities of different coating durations of three nanoparticle (NP) coatings: molybdenum (Mo), tantalum (Ta), and zinc oxide (ZnO), and their effects on the surface characteristics of 316L stainless steel (SS). The coated substrates underwent characterization utilizing field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectrometry (EDX), and X-ray diffractometer (XRD) techniques. The antibacterial efficacy of NPs was evaluated using the agar diffusion method. The FE-SEM and EDX images confirmed the presence of nano-sized particles of Mo, Ta, and ZnO on the surface of the substrates with perfectly symmetrical spheres and a uniform distribution of
... Show MoreArab-Islamic architecture has undergone a change at multiple levels affected by modern technology, so the research sought to address the role of contemporary technologies on a fundamental and fundamental component of architecture, which is the architectural space, what is known as the essence of architecture and its ultimate destination, with a focus on the architectural space in the architecture of the contemporary Arab Islamic mosque, because the mosque’s architecture is so important in Islamic law and the belief of the Muslim person himself, where the mosque is the functional style produced by the Islamic faith and embodied in it, whereas, knowing the levels of influence of contemporary technologies in the architectural spac
... Show MoreThe study conducted on the compositions of epiphytic diatoms on three taxa of aquatic plants were selected (Phragmites australis Trin ex stand , Ceratophyllum demersum L. and Typha domengensis Pers) in three sites within Al-Auda Marsh, from autumn 2013 to summer 2014 . The study was measured physical and chemical factors of all the study sites, such as: air temperature, power of hydrogen (pH), electrical conductivity (EC), salinity (S‰), total hardness(TH), dissolved oxygen (DO), and plant nutrient. The results showed that water of marsh was oxygenated and it was very hard. A total of 111 taxa of phytoplankton were identified, which belonged to 13 families and 26 genus (one family and two genus of centric diatoms, 12 families and 26 ge
... Show MoreThe current research aims to study the extent to which the Independent High Electoral Commission applies to information security risk management by the international standard (ISO / IEC27005) in terms of policies, administrative and technical procedures, and techniques used in managing information security risks, based on the opinions of experts in the sector who occupy positions (General Manager The directorate, department heads and their agents, project managers, heads of divisions, and those authorized to access systems and software). The importance of the research comes by giving a clear picture of the field of information security risk management in the organization in question because of its significant role in identifying risks and s
... Show MoreIn this research study the effect of fish on the properties optical films thickness 1200-1800 and calculated energy gap Basra direct transport permitted and forbidden to membranes and urged decreasing values ??of Optical Energy Gap increase fish included accounts optical also calculate the constants visual as factories winding down and the refractive index and reflectivity membranes also by real part and imaginarythe dielectric constant
After the Napoleonic Code of 1804 came without any legal rules specific to the duration of the contract, and was content to refer to it in scattered legal texts, Legislative Decree No. 2016-131 came to establish a comprehensive legal system for the duration of the contract, starting from the period of its formation, through the period of its implementation, and ending with its continuation after the expiration of its term, in the third section of the fourth chapter related to the effects of the contract (Articles 1210 - 1215), relying on judicial precedents on the one hand - which are many, as will be shown through the research pages - and contractual practices on the other hand. Perhaps the main motive that prompted the French legislator t
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