Experimental study of heat transfer coefficients in air-liquid-solid fluidized beds were carried out by measuring the heat rate and the overall temperature differences across the heater at different operating conditions. The experiments were carried out in Q.V.F. glass column of 0.22 m inside diameter and 2.25 m height with an axially mounted cylindrical heater of 0.0367 m diameter and 0.5 m height. The fluidizing media were water as a continuous phase and air as a dispersed phase. Low density (Ploymethyl-methacrylate, 3.17 mm size) and high density (Glass beads, 2.31 mm size) particles were used as solid phase. The bed temperature profiles were measured axially and radially in the bed for different positions. Thermocouples were connected to an interface system and these measurements were monitored by computer on line. Theoretical analysis has been carried out to solve the differential equation governing heat transfer in the gas-liquid-solid fluidized system with its boundary conditions. Finite difference technique was used as a suitable numerical method to find the solution. By applying the temperature profiles found experimentally in solved equation, effective thermal conductivity values were found.
Summary:
The A. H. 7th century had witnessed an obvious development
in the Yemeni scientific process. The most important reason
being the establishment of the Resooliy State (A. H. 626-858)
which had achieved economic and scientific prosperity in
various fields of knowledge. Its sultans had participated in
building schools, purchasing books, summoning of scientists,
presenting gifts, and encouraging scientific journeys in and out
of Yemen. Therefore, studies had thrived and authorship
widened, and there appeared not a few number of scientists..
A polycrystalline CdTefilms have been prepared by thermal evaporation technique on glass substrate at room temperature. The films thickness was about700±50 nm. Some of these films were annealed at 573 K for different duration times (60, 120 and 180 minutes), and other CdTe films followed by a layer of CdCl2 which has been deposited on them, and then the prepared CdTe films with CdCl2 layer have been annealed for the same conditions. The structures of CdTe films without and with CdCl2 layer have been investigated by X-ray diffraction. The as prepared and annealed films without and with CdCl2 layer were polycrystalline structure with preferred orientation at (111) plane. The better structural pr
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In his life, a person engages in different types of verbal and actual dispositions that result in various effects, some of which are necessary and not valid, such as selling, and some are not necessary for one of the two contracting parties, such as a mortgage or both, such as lending and agency. However, there are some actions that are sometimes necessary and not necessary at other times, such as a gift that indicates in its simplest sense. Owning money for another without compensation, it is one of the doors of benevolence and benevolence, and it is one of the attributes of perfection with which God, may He be glorified and exalted be He, described Himself. - And if this analogy is the difference - and distanced himself from greed, the
... Show MoreAttention increased to the topic of academic accreditation by the university as a modern philosophy by which to improve its performance and provide high-quality education. Universities and colleges in general and Iraqi universities and colleges in particular have begun interest in accreditation and desire to get it. So starting from the pursuit of the Administration and Economics College / Baghdad University in obtaining accreditation of Association to Advance Collegiate Schools of Business (AACSB) The research is present which aims to determine the level of application (AACSB) International standards at the College of Administration and Economics / Baghdad University in preparation to get its accreditation in the future. Researc
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Buzurgan oil Field which is located in south of Iraq has been producing oil for five decades that caused production to drop in many oil wells. This paper provides a technical and economical comparison between the ESP and gas lift in one oil well (Bu-16) to help enhancing production and maximize revenue. Prosper software was used to build, match and design the artificial lift method for the selected well, also to predict the well behavior at different water cut values and its effect on artificial lift method efficiency. The validity of software model was confirmed by matching, where the error difference value between actual and calculated data was (-1.77%).
The ESP results showed the durability of ESP regarding th
... Show MoreSome have considered the dialectic in form and meaning from different points of view, and dismantled them from each other, and this view is correct if we adopt according to the logic of Aristotle when it comes to dialectic, the dialectic of form and meaning has different aspects and does not share a single line in terms of conceptual meaning, the form is the appearance What the recipient sees with the help of cognitive tools, the content or content is the mental meaning, which in turn depends on his own tools, and to this extent this view is correct, and the intellectual content or meaning of the artwork or the human message that the artist wants to convey to the viewer.
The research included four chapters. The first chapter included
Playing is the only common language among children in every place and time, to the fact that what distinguishes the children is their quest to play and fun way innate, not acquired, which is expressed with the child really is one of the rights. And play a key entrance to the growth of the child mentally, intellectually and cognitively and not for the child emotionally and socially just. In the play the child begins to identify and classify objects and learn concepts and circulate among themselves on a linguistic basis. Activity here and play a major role in leading the linguistic development of the child in the composition has the communication skills.
The Games (especially intellectual ones) Whatever the cause of the development
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Some new heterocyclic compounds containing, cyclohexenone, indazole, isoxazoline, pyrmidine and pyrazoline ring system were prepared from chalcones (1a,b). The starting chalcones (1a,b) were obtained by a base catalyzed condensation of appropriately substituted benzaldehydes and 2-acetylbenzofuran. The reaction of the prepared chalcones with ethylacetoacetate/hydrazine hydrate, hydroxylamine hydrochloride, urea, thiourea, hydrazine hydrate, phenyl hydrazine or hydrazide derivatives gave the mentioned heterocycles. All synthesized compounds have been characterized by physical and spectral methods.
This research examines the phenomenon of the Arabic language repeated in the Qur'an and poetry, as some morphological formulas are valid in their uses and indications in more than one way. search).
This paper investigates the collocational use of irreversible food binomials in the lexicons of English (UK) and Arabic (Iraq), their word-order motivations, cultural background, and how they compare. Data consisted in sixteen pairs in English, versus fifteen in Arabic. Data analysis has shown their word order is largely motivated by logical sequencing of precedence; the semantically bigger or better item comes first and the phonologically longer word goes last. These apply in a cline of decreasing functionality: logical form first, semantic importance second, phonological form last. In competition, the member higher in this cline wins first membership. While the entries in each list clearly reflect culturally preferred food meals in the UK
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