The aim of this research is to study the factors affecting drag coefficient (C d ) in
non-Newtonian fluids which are the rheological properties ,concentrations of non-
Newtonian fluids, particle shape, size and the density difference between particle and
fluid .Also this study shows drag coefficient (C d ) and particle Reynolds' number (Re
P ) relationship and the effect of rheological properties on this relationship.
An experimental apparatus was designed and built, which consists of Perspex pipe
of length of 160 cm. and inside diameter of 7.8 cm. to calculate the settling velocity,
also electronic circuit was designed to calculate the falling time of particles through
fluid.
Two types of solid particles were used; glass spheres and crushed rocks as
irregularly shaped particles with different diameters and compared with each other.
The concept of equivalent spherical diameter (D S ) was used to calculate the
diameters of irregularly shaped particles.
The flow behavior for Non-Newtonian fluids was represented by Power-Law model.
Two types of polymers were used, Carboxy Methyl Cellulose CMC with
concentrations of (3.71, 5, 15 and 17.5) g/l and polyacrylamide with concentrations of
(2, 4 and 6) g/l.
The results showed that the drag coefficient decreased with increasing settling
velocity and particle diameters and sizes; and increased as fluid become far from
Newtonian behavior and concentrations and the density difference between particle
and fluid.
The results also showed that the rheological properties of Non-Newtonian fluids
have a great effect on the drag coefficient and particle Reynolds number relationship,
especially in laminar-slip regime and decreases or vanishes at transition and turbulentslip
regimes.
New correlations were obtained which relates drag coefficient with concentrations
of polymers and with flow behavior indices for spherical and irregular shaped
particles in Carboxy Methyl Cellulose CMC and polyacrylamide solutions.
New polymer blend with enhanced properties was prepared from (80 %) epoxy resin (Ep), (20%) unsaturated polyester resin (UPE) as a matrix material. The as-obtained polymer blend was further reinforced by adding Sand particles of particle size (53 μm) with various weight fraction (5, 10, 15, 20 %). Thermal conductivity and sorption measurements are performed in order to determine diffusion coefficient in different chemical solutions (NaOH, HCl) with concentration (0.3N) after immersion for specific period of time (30 days). The obtained results demonstrate that the addition of sand powder to (80%EP/20%UPE) blend leads to an increase of thermal conductivity, with an optimum/minimum diffusion coefficient in (HCl)/(NaOH), respectively.
Giardiasis is an infection caused by the protozoan flagellate parasite Giardia spp. in the intestine. G duodenalis, a species complex of diverse genotypes that tend to demonstrate host specificity, is responsible for most veterinary health related infections; production animals, companion animals, and wildlife can all be infected. Abdominal pain and diarrhea, typically accompanied by steatorrhea, are the most common symptoms of Giardiasis. Cysts or antigens in feces are commonly used to diagnose the disease. Treatment regimens vary and are dependent on the indication. Control methods must include hygiene measures. Despite direct evidence of Giardia sp transmission to humans via polluted water supplies, our analysis will focus on some r
... 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 MoreInelastic longitudinal electron scattering form factors to 2+ and 4+ states in 65Cu nucleus has been calculated in the (2p3/2 1f 5/2 2p1/2) shell model space with the F5PVH effective interaction. The harmonic oscillator potential has been applied to calculate the wave functions of radial single-particle matrix elements. Two shell model codes, CP and NUSHELL are used to obtain results. The form factor of inelastic electron scattering to 1/21−, 1/22−, 3/22−, 3/23−, 5/21−, 5/22− and 7/2- states and finding the transition probabilities B (C2) (in units of e2 fm4) for these transitions and B (C4) (in units of e2 fm8) for the transition 7/2-, and comparing them with experimental data. Both the form factors and reduced transition pr
... Show MoreBackground: Childhood meningitis is a major
cause of morbidity and mortality, Hemophilus
influenza b (Hib) is the most common cause in
many countries, especially below 5 years and
before the development of conjugated Hib vaccine,
it is followed by Streptococcus Pneumonia, and
then N. meningitides, in addition to other
microorganisms.
Objective: To identify the causative organisms
of bacterial meningitis and to identify the factors
predisposing significantly to the incidence of
bacterial meningitis.
Method: This cross sectional , study was done in
Al-Elwia Pediatric Hospital during the period 1st
of January 2007 to 30th of June 2007.Eighty four
patients with presumptive diagnosis of meningitis<
The purpose of the search definition on factors superior this whoever impact on the improvement the exploitation decision this detect on stock exchange markets assumption , and using questioners to data accumulate and the Iraq market of financial papers battleground to search annoy chose the eyeball extension (47) peoples from peoples employees on the market , and using the bought statistic program (SPSS) on input and analysis search data , and machinate the search outputs to their group of factors internal and external which impact on exploitation decision on financial papers markets , and the search commend on necessary rise the incumbency direction in the stock exchange
... Show MoreInflammation markers are significantly higher among hemodialysis (HD) patients, which have been associated with chronic activation of the immune system. Hemodialysis centers in Baghdad appear to be taking measures with low adequacy and frequency of dialysis sessions, which can be a reason for decreased kidney functions. Therefore, the objective of this study focuses on the assessment of different aspects of hemodialysis for regular HD patients in Baghdad, including inflammatory markers (serum C-reactive protein, CRP, and erythrocyte sedimentation rate, ESR), dialysis dose, comorbidities, and demographic factors for a period of one year (2018), the assessment covered four major hospitals in Baghdad namely (Al-Kind
... Show MoreIn this article, we developed a new loss function, as the simplification of linear exponential loss function (LINEX) by weighting LINEX function. We derive a scale parameter, reliability and the hazard functions in accordance with upper record values of the Lomax distribution (LD). To study a small sample behavior performance of the proposed loss function using a Monte Carlo simulation, we make a comparison among maximum likelihood estimator, Bayesian estimator by means of LINEX loss function and Bayesian estimator using square error loss (SE) function. The consequences have shown that a modified method is the finest for valuing a scale parameter, reliability and hazard functions.
This study aimed to measure the accounting conservatism and the lemited factors which affected on it in the annual financial reports of insurance companies which listed on the Amman Stock Exchange during the period from 2005 to 2016, these factors were represented by firm age, firm debt and firm size.
Using the market value model (MV) To book value ( BV) Beaver and Ryan (2000) The level of the accounting conservatism was measured. The study found that the insurance companies which are listed on the ASE exercise the accounting conservatism when they were preparing financial reports. And when conducting a process of the test of the affected of the factors (The age of the
... Show More Depending on the high resistance to antibiotics, five isolates of Pseudomonas aeruginosa and 7 isolates of Serratia fonticola were selected out of 150 bacterial isolates from burn wards in Baghdad hospitals, which were later identified by VITEK2. A susceptibility test was done by using 15 antibiotics. The results showed that all the selected isolates were resistant to antibiotics: AMP, CTX, CAZ, GEN, PIP, TIC and TMP especially, while they were sensitive to IPE. The essential oils of Aloysia citrodora (Family: Verbenaceae), Rosmarinus officinalis (Family: Lamiaceae) and