In this work, the effect of variation of semi-angle of the conical part on the vibration characteristics of cylindrical-conical coupled structure is investigated. The shell is made of polyester resin reinforced by continuous E-glass fibers. The case is analyzed experimentally and numerically for orthotropic shell structures. The experimental program is conducted by exciting the fabricated structure by an impact hammer and monitoring the response using an attached accelerometer for different semi-angles of the conical part.
Software named SIGVIEW is used to perform the signal processing on the acquired signal in order to measure the natural frequencies and the corresponding mode shapes. The numerical investigation is achieved using ANSYS (Finite Element software) which was verified by the experimental results. Good agreement is achieved when comparing the experimental and numerical results. The maximum deviation in results was found to be (5.9%). The maximum relative nodal rotational and translational amplitudes associated with the
first normal mode of the orthotropic and isotropic shells are noted for the structure of semi-angle of cone of 45o .
Abstract
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.
The biosorption of Pb (II), Cd (II), and Hg (II) from simulated aqueous solutions using baker’s yeast biomass was investigated. Batch type experiments were carried out to find the equilibrium isotherm data for each component (single, binary, and ternary), and the adsorption rate constants. Kinetics pseudo-first and second order rate models applied to the adsorption data to estimate the rate constant for each solute, the results showed that the Cd (II), Pb (II), and Hg (II) uptake process followed the pseudo-second order rate model with (R2) 0.963, 0.979, and 0.960 respectively. The equilibrium isotherm data were fitted with five theoretical models. Langmuir model provides the best fitting for the experimental results with (R2) 0.992, 0
... Show MoreThe natural polyphenolic compound that cinnamon contains is well known for its various biological activities, a broad variety of pharmacological and therapeutic properties. Diversified biomedical and pharmacological applications benefit from organic nanoparticles with controlled properties. Bioactive and non-toxic, cinnamon nanoparticles (CNPs) can be effective antibacterial agents. Driven by this idea, we prepared spherical CNPs using liquid (PLAL) pulse laser ablation technique and defined those NPs. Using Q-switched Nd : YAG With a wavelength of 1064 nm pulse laser of constant energy 500 mj , And different laser pulses ( 250 , 500 , 750 , 1000 ) pulse /sec a pure cinnamon target submerged in
... Show MoreBackground: Periodontal diseases are initiated by microbial plaque, which accumulates in the sulcular region and induces an inflammatory response. The Receptor activator of nuclear factor-kappa B ligand / osteoprotegerin (RANKL/OPG) axis is involved in the regulation of bone metabolism in periodontitis, in which an increase in receptor activator of nuclear factor-kappa B ligand or a decrease in osteoprotegerin can tip the balance in favor of osteoclastogenesis and the resorption of alveolar bone that is the hallmark of periodontitis. This study was performed to investigate the role of salivary levels of RANKL and OPG in pathogenesis of chronic periodontitis. Subjects and Methods: Fifty five subjects with chronic periodontitis with ages rang
... Show MoreBackground: Cutaneous leishmaniasis (CL) is a neglected disease in tropical countries, including Iraq. Several studies have sought to examine chemotherapies for leishmaniasis treatment but most of them are of toxic and/or undesirable side effect, therefore, the need for investigating new fewer toxic therapies is essential. Aim of study: In this study, the cytotoxic effect of Artemisinin (ART), a novel herbal compound, was screened against the two forms, promastigotes and amastigotes, of the Iraqi isolate of Leishmania tropica, the causative agent of Baghdad boil. Material and methods: Different concentrations (1000, 500, 250, 125, 62.5, 31.25, 15.6 and 7.8) µM of Artemisinin were screened to investigate the leishmanicidal activity of th
... Show MoreMass transfer was examined at a stationary rectangular copper electrode (cathode) by using the reduction of cupric ions as the electrochemical reaction. The influence of electrolyte temperature (25, 45, and 65 oC), and cupric ions concentration (4, 8, and 12 mM) on mass transfer coefficient were investigated by using limiting current technique. The mass transfer coefficient and hence the Sherwood number was correlated as Sh =
Were not experience Khalil Hawi capillary module as presented or routine in the format
of the implications , but was saturated transitions quality that targeted built by visionary and
mechanisms expressive , Valgosaidp when the container is a clash between two worlds world
Nahdi to promote world on the ashes , and often strained poet himself to achieve an approach
between worlds , and in the midst of those caesarean section exhausted poet in touch his tools
and visions , and this is why the poetry Hawi toward westernization expressive as a result of
the conflict concepts chronic , be sure to researcher not engaged in the overall qualitative
changes in the structure and content, but the goal Acetknah level that qualit
Profiles of indignation and indiscretion in pre-Islamic poetry
The enhancement of heat exchanger performance was investigated using dimpled tubes tested at different Reynolds numbers, in the present work four types of dimpled tubes with a specified configuration manufactured, tested and then compared performance with the smooth tube and other passive techniques performance. Two dimpled arrangements along the tube were investigated, these are inline and staggered at constant pitch ratio X/d=4, the test results showed that Nusselts number (heat transfer) of the staggered array is higher than the inline array by 13%. The effect of different depths of the dimple (14.5 mm and 18.5 mm) has been also investigated; a tube with large dimple diameter enhanced the Nusselts number by about 25% for the ran
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