The present work considers an alternative solution for a complex configuration of rotor discs by applying Galerkin Method. The theoretical model consists of elastic shaft carrying number of discs and supported on number of journal bearings. The equation of motion was discretized to finite degree of freedom in terms of the system generalized coordinates. The various effects of the dynamical forces and moments arising from the bearing, discs and shaft were included. Rayleigh beam model is used for analyzing the shaft while the discs are considered rigid . The validity and convergence of the present analysis was carefully checked by comparing with the Finite Element solution. An example of rotor consists of three different size discs and supported by two journal bearing was considered for the numerical solution .The results shows good agreements between the two methods ,where the maximum error not exceeds 5%. The convergence test showed that using few modes (not more than 6) are sufficient for the accurate analysis. The forward and backward whirl was investigated experimentally .The experimental results of a two discs rotor ,show a reasonable agreement where the maximum error not exceeds 11%. The unbalance response, Cambpell diagram, orbit response were plotted .The effects of geometry, disc sizes , location and arrangement on the unbalance response and natural frequencies of three discs rotor were further investigated .
Animal fats are a good, promising and ethical alternative source for biodiesel production, but they need more complex treatments than vegetable oils. Iraqi butchery plants waste fats (sheep fat) which are suggested as feedstock to produce biodiesel. This type of fat contains a large quantity of free fatty acids (FFAs) (acid number 49.13 mg KOH/g of fat). The direct transesterification of such fats produce high amount of soap instead of desired biodiesel, so a pre-treatment step (to reduce FFAs) is necessary before transesterification. This step was done by esterification of the free fatty acids in the fat by adding ethanol and using 1% acid catalyst (H2SO4) for 30 minutes. The results showed that the acid number of sheep fat after pre-tr
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This study aims to identify the empathy of University Students, as well as the significant differences in sympathy in terms of gender and specialization. To achieve the aims of the study, a scale of empathy was administered to a sample of (450) students collected randomly from Baghdad university. The results showed that the study sample has a level of empathy. There is a significant difference between males and females in empathy, in favor of the female students. There is no significant difference in empathy in terms of specialization (scientific, humanities), and the interaction between males and females. The study came out with a number of recommendations and suggestions.
Profiles of indignation and indiscretion in pre-Islamic poetry
In this work, an investigation for the dynamic analysis of thin composite cylindrical and spherical shells is presented. The analytical solution is based upon the higher order shear deformation theory of elastic shells from which the developed equations are derived to deal with orthotropic layers. This will cover the determination of the fundamental natural frequencies and mode shapes for simply supported composites cylindrical and spherical shells.
The analytical results obtained by using the derived equations were confirmed by the finite element technique using the well known Ansys package. The results have shown a good agreement with a maximum percentage of discrepancy, which gives a confidence o
... Show MoreBackground: Morganella morganii is one of the important nosocomial pathogens that may cause urinary tract infection and bacteremia.Methods: The above bacterium was identified from 250 bacterial strains which were isolated from 220 urine samples of patients with urinary tract infection. Antimicrobial susceptibility, by using disk diffusion method, of isolates was tested against some antibiotics.Results: Two M. moganii strains were isolated from female catheterized urinary tract patients, and identified by conventional biochemical tests and API20E system at the first time in Iraq. Both of them produced urease and hemolysin. Antimicrobial susceptibility test showed that these strains are resistant to, amoxicillin-clavulanate, cephalothin, g
... Show MoreNew complexes of M(II) with mixed ligand of 5-Chlorosalicylic acid (CSA) C7H5ClO3 as primary ligand and L- Valine (L-Val) C5H11NO2 as a secondary ligand were prepared and characterized by elemental analysis (C.H.N), UV., FT-IR, magnetic susceptibility, μeff (B.M) as well as the conductivity measurements (Λm ). In the complexes, the 5-chlorosalicylic acid is bidentate in all complexes coordinating through –OH- and –COO- groups; also L-Valine behaves as a bidentate ligand in all complexes through –NH2 and –COO- groups. These five mixed ligand complexes formulated as Na3[M(CSA)2(L-Val)]. The proposed molecular structure for all complexes is octahedral geometries. The synthesis complexes were tested in vitro for against four bacteria
... Show MoreNew, easy, simple, and fast spectral method for estimation of sulfamethoxazole (SMZ) in pure and pharmaceutical forms. The proposed method is based on the azotization of the drug compound by sodium nitrite in an acidic medium and then coupling with 2,3dimethyl phenol reagent (DMP) in a basic medium to yield an orange-coloured dye which shows λmax at 402 nm. Different affection of the optimization reaction has been completed, following the classical univariate sequence. The concentration of sulfamethoxazole about (1-15) μg. mL-1 with molar absorptivity of (14943.461) L.mol1 .cm-1 that obeyed Beer’s law. The detection and quantification limits were (0.852, 2.583) μg. mL-1 respectively, while the value of Sandell’s sensitivity (
... Show MoreNew complexes of M(II) with mixed ligand of 5-Chlorosalicylic acid (CSA) C7H5ClO3 as primary ligand and L- Valine (L-Val) C5H11NO2 as a secondary ligand were prepared and characterized by elemental analysis (C.H.N), UV., FT-IR, magnetic susceptibility, µeff (B.M) as well as the conductivity measurements (Λm ). In the complexes, the 5-chlorosalicylic acid is bidentate in all complexes coordinating through –OH- and –COO- groups; also L-Valine behaves as a bidentate ligand in all complexes through –NH2 and –COO- groups. These five mixed ligand complexes formulated as Na3[M(CSA)2(L-Val)]. The proposed molecular structure for all complexes is octahedral geometries. The synthesis complexes were tested in vitro for against four bacteria
... Show MoreBackground: Joubert syndrome (JS) is a very rare autosomal recessive disorder characterized by agenesis of cerebellar vermis, abnormal eye movements, respiratory irregularities, and delayed generalized motor development. Retinal dystrophy and cystic kidneys may also be associated with this clinical syndrome. The importance of recognizing JS is related to the outcome and its potential complications. This syndrome is difficult to diagnose clinically because of its variable phenotype. Its neuroimaging hallmarks include the characteristic molar tooth sign and bat wing-shaped fourth ventricle
New complexes of M(II) with mixed ligand of 5-Chlorosalicylic acid (CSA) C7H5ClO3 as primary ligand and L- Valine (L-Val) C5H11NO2 as a secondary ligand were prepared and characterized by elemental analysis (C.H.N), UV., FT-IR, magnetic susceptibility, μeff (B.M) as well as the conductivity measurements (Λm ). In the complexes, the 5-chlorosalicylic acid is bidentate in all complexes coordinating through –OH- and –COO- groups; also L-Valine behaves as a bidentate ligand in all complexes through –NH2 and –COO- groups. These five mixed ligand complexes formulated as Na3[M(CSA)2(L-Val)]. The proposed molecular structure for all complexes is octahedral geometries. The synthesis complexes were tested in vitro for against four bacteria
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