In the present study the performance of drying process of dffirent solid materials by batch fluidized bed drying
under vacuum conditions was investigated. Three, different solid materials, namely; ion exchange resin-8528,
aspirin and paracetamol were used. The behavior of the drying curves as well as the rate of drying of these
materials had been studied. The experiments were caried out in a 0.0381 m column diameter fluidized by hot
air under yacuum conditions. Four variables affecting on the rate of drying were studied' these variables are
vacuum pressure (100 - 500 mm Hg), air temperature (303-323 K), particle size (0.3-0.8 mm) and initial
moisture content (0.35-0.55 g/g solid)-for resin and (0.1-0.2 g/g soltid) for aspirin and paracetamol. The study of
the characteristics of the drying curves showed that the drying behavior depends mainly on the type of the solid
material and on the operating conditions. It was found that the drying rate at vacuum conditions is enhanced by
increasing the operating temperature of the air and decreases by increasing the initial moisture content of the
material and the particle size. Moreover, an experiment was carried out to study the drying of aspirin solid
material which is dried in atmospheric fluidized bed dryer operating at the same conditions to compare the
temperature and time needed in both techniques. It was found that the temperature needed for vacuum fluidized
bed dryer (303 K) is less than needed by fluidized bed dryer operating at atmospheric pressure (323 K). A
simpliled model'for the drying of solids in the constant-rate period in a batch fluidized bed is developed,
considering the bed to consist of dense phase and bubble phase with heat and mass transfer between the phases.
It is assumed that the solids in dense phase to be in thermal equilibrium with the interstitial gas in the dense
phase. The bubble size, its rise velocity, and the bubble volume fraction are taken into account while developing
the model. The model is compared with experimental data reported in this study and found to match
satisfactorily.
Efficient and cost-effective drilling of directional wells necessitates the implementation of best drilling practices and advanced techniques to optimize drilling operations. Failure to adequately consider drilling risks can result in inefficient drilling operations and non-productive time (NPT). Although advanced drilling techniques may be expensive, they offer promising technical solutions for mitigating drilling risks. This paper aims to demonstrate the effectiveness of advanced drilling techniques in mitigating risks and improving drilling operations when compared to conventional drilling techniques. Specifically, the advanced drilling techniques employed in Buzurgan Oil Field, including vertical drilling with mud motor, managed pres
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The aim of this paper is to study the nonlinear delay second order eigenvalue problems which consists of delay ordinary differential equations, in fact one of the expansion methods that is called the least square method which will be developed to solve this kind of problems.
Motivation is one of the most important factors that influence students learning and has a great effect on their success and achievement. For this reason, in this paper, the researcher is going to investigate the motivational teaching strategies used by EFL Iraqi school teachers. To achieve the aim of the study, the researcher adapted a questionnaire with some changes and modification’s. This questionnaire with five point scale (always, often, sometimes, rarely and never). To achieve face validity, the questionnaire items are given to a jury of experts. Alpha Cronbach formula is used to achieve the questionnaire reliability. After that, the questionnaire was applied on a sample of 38 teachers during the academic year 2019-2020. Th
... Show MoreTranslation is a vital process that needs much more understanding and mutual background knowledge on the part of ESL or EFL learners in terms of grammar , meaning and context of both the SL and TL . Thus , the main aim of the current research paper is to identify and figure out the techniques used by ESL or EFL learners when translating English barnyard verbs into Arabic . The main problem of this study is attributed to the fact that ESL or EFL learners may not be able to identify and understand the connotative meaning of barnyard verbs since these verbs are onomatopoeic (i.e,) a word that phonetically imitates, or suggests the source of sound that it describes. Therefore they may be unable to translate these verbs appropriately and accura
... Show MoreThe current study is concerned with investigating the difficulties that Iraqi EFL learners of English may face when translating English collective nouns. Such collective nouns as committee, government, , jury , Parliament , etc. are considered singular when the concept of the unity as a group is emphasized , but when the concept of the individuals or numbers is emphasized they are treated as plural. A sample of twenty undergraduate students have been selected randomly to translate certain English collective nouns in some selected political texts in order to find out the difficulties they might face in rendering them into Arabic. It is hypothesized that most of the testees have used the singular form rather than the plural ignoring the
... Show MoreFinding orthogonal matrices in different sizes is very complex and important because it can be used in different applications like image processing and communications (eg CDMA and OFDM). In this paper we introduce a new method to find orthogonal matrices by using tensor products between two or more orthogonal matrices of real and imaginary numbers with applying it in images and communication signals processing. The output matrices will be orthogonal matrices too and the processing by our new method is very easy compared to other classical methods those use basic proofs. The results are normal and acceptable in communication signals and images but it needs more research works.
In this paper, we focus on designing feed forward neural network (FFNN) for solving Mixed Volterra – Fredholm Integral Equations (MVFIEs) of second kind in 2–dimensions. in our method, we present a multi – layers model consisting of a hidden layer which has five hidden units (neurons) and one linear output unit. Transfer function (Log – sigmoid) and training algorithm (Levenberg – Marquardt) are used as a sigmoid activation of each unit. A comparison between the results of numerical experiment and the analytic solution of some examples has been carried out in order to justify the efficiency and the accuracy of our method.
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Simulation of direct current (DC) discharge plasma using
COMSOL Multiphysics software were used to study the uniformity
of deposition on anode from DC discharge sputtering using ring and
disc cathodes, then applied it experimentally to make comparison
between film thickness distribution with simulation results. Both
simulation and experimental results shows that the deposition using
copper ring cathode is more uniformity than disc cathode
Nanoparticle has pulled in expanding consideration with the developing enthusiasm for nanotechnology which hold potential as essential segments for development applications. In the present work, a copper nanoparticle is manufactured as a suspension in distilled water by beating a bulk copper target with laser source (532 nm wavelength, 10 ns pulse duration and 10 Hz repletion rate) via method. UV- visible absorption spectra and AFM analysis has been done to observe the effect of repetition rate for the pulsation of laser. Copper nanoparticles (Cu-NPs) were successfully synthesized with green color. The Cu- NPs have very high purity because the preparation was managed in aqueous media to eliminate ambient contaminations. Absorption
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The cinematographer mediates through the means of cinema and television a set of elements complementing each other in the light of developments in various sciences, culture and arts for the purpose of conveying the meaning to the recipient and achieve aesthetic taste. Despite the diversity of cinematographic media with its multiple forms, The researcher started from the principle of definition and knowledge of a technical phenomenon that emerged in the cinematographic medium through the treatment of dramatic events through the solutions of the exit line depends on the narrative of events in one place contributes to attract Mam spectator since this interesting phenomenon in the mediator, there .van question arises the adoption of that vis
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