In this paper, design computationl investigation in the field of charged-particle optics with the aid of numerical analysis methods under the absence of space charge effects. The work has been concentrated on the design of three-electrode einzel electrostatic lens accelerating and decelerating operated under different magnification conditions. The potential field distribution of lens has been represented by exponential function. The paraxial-ray equation has been solved for the proposed field to determine the trajectory of charged-particles traversing in the lens. From The axial potential distribution and its first and second derivatives, the optical properties such as the focal length and the spherical and chromatic aberration coefficients have been computed, the electrode shape of lens has been determined by using SIMION computer program . In this research , design electrostatic einzel lens three-electrode accelerating and decelerating L=2mm, 20mm operated under different magnification conditions (zero, infinite, finite). The electrode shape of the electrostatic lens was then determined from the solution of the Laplace's equation. The results showed low values of spherical and chromatic aberrations which are considered as good criteria for good design
In this part of programme , different bacterial isolates mainly Salmonella spp, Shigella spp and Escherichia coli were used for antagonism with Saccharomyces boulardii under different conditions . S.boulardii was grown under aerobic conditions and antagonized with young overnight nutrient broth cultures of test bacterial isolates and other kept in refrigerator for a week after full growth . Young cultures were more susceptible to antagonistic effect of yeast compared to old cultures and on isolates grown on solid medium for 24 hr. S.boulardii grown under aerobic and microaerobic conditions and antagonized with overnight broth cultures of test bacterial isolates , The results revealed that aerobic cultures of yeast had more inhibito
... Show MoreSalt stress negatively affects germination and seedling growth. Sorghum cultivars (Bohuth70, Inqath and Rabeh), seed soaking in dry yeast extract (3, 6 and 9 g l-1) in addition to dry seeds and electrical conductivity (4, 10 and 16 dS m-1) were studied. Traits of germination ratio at first and final counts, lengths of radicle and plumule, seedling dry weight and seedling vigour index were studied. The cultivar of Bohuth70 and concentration of yeast extract (9 g l-1) were superior at all studied traits, while all traits values were reduced with increased saline stress. The combination (Bohuth70×9×4) was superior to most other treatments at first and final counts, radicle length and seedling dry weight, while superiority of plumule length a
... Show MoreIn this study, the effect of design parameters such as pipe diameter, pipe wall thickness, pipe material and the effect of fluid velocity on the natural frequency of fluid-structure interaction in straight pipe conveying fully developed turbulent flow were investigate numerically,analytically and experimentally. Also the effect of support conditions, simply-simply and clamped-clamped was investigated. Experimentally, pipe vibrations were characterized by accelerometer mounted on the pipe wall. The natural frequencies of vibration were analyzed by using Fast Fourier Transformer (FFT). Five test sections of two different pipe diameters of 76.2
mm and 50.8 mm with two pipe thicknesses of 3.7 mm and 2.4 mm and two pipe materials,stainles
The effect of time (or corrosion products formation) on corrosion rates of carbon steel pipe in aerated 0.1N NaCl
solution under turbulent flow conditions is investigated. Tests are conducted using electrochemical polarization
technique by determining the limiting current density of oxygen reduction in Reynolds number range of 15000 to 110000
and temperature range of 30 to 60oC. The effect of corrosion products formation on the friction factor is studied and
discussed. Corrosion process is analyzed as a mass transfer operation and the mass transfer theory is employed to
express the corrosion rate. The results are compared with many proposed models particularly those based on the
concept of analogy among momentum, heat,
The research objective was to study the amount of lost fluids, some blood components and mineral salts in volleyball players under hot weather conditions. The sample of the present study was composed of 12 volleyball players of Al-Sinaa Club (Baghdad, Iraq) in the 2022/2023 season. The variables analyzed in this study were: Heart rate before and after exercise, internal and external body temperature before and after exertion, potassium ion, sodium ion, calcium ion, and the amount of fluid lost (the player's weight) before and after the exercise. The tests were conducted at a temperature between 42-47 degrees Celsius. The maximum anaerobic exercise was performed with volleyball. The results showed that to play volleybal
... Show MoreThe research objective was to study the amount of lost fluids, some blood components and mineral salts in volleyball players under hot weather conditions. The sample of the present study was composed of 12 volleyball players of Al-Sinaa Club (Baghdad, Iraq) in the 2022/2023 season. The variables analyzed in this study were: Heart rate before and after exercise, internal and external body temperature before and after exertion, potassium ion, sodium ion, calcium ion, and the amount of fluid lost (the player's weight) before and after the exercise. The tests were conducted at a temperature between 42-47 degrees Celsius. The maximum anaerobic exercise was performed with volleyball. The results showed that to play volleybal
... Show MoreA computational investigation is carried out in the field of charged particle optics with the aid of the numerical analysis methods. The work is concerned with the design of symmetrical double pole piece magnetic lens. The axial magnetic flux density distribution is determined by using exponential model, from which the paraxial-ray equation is solved to obtain the trajectory of particles that satisfy the suggested exponential model. From the knowledge of the first and second derivatives of axial potential distribution, the optical properties such as the focal length and aberration coefficients (radial distortion coefficient and spiral distortion coefficient) are determined. Finally, the pole piece profiles capable of pr
... Show MoreThis work involves theoretical and experimental studies for seven compounds to calculate the electrons spectrum and NLO properties. The theoretical study is done by employing the Time Depending Density Functional Theory TD-DFT and B3LYP/high basis set 6-311++G (2d,2p), using Gaussian program 09. Experimental study by UV/VIS spectrophotometer device to prove the theoretical study. Theoretical and experimental results were applicable in spectrum and energy gap values, in addition to convergence theoretically the energy gap results from ΔEHOMO-LUMO and UV/VIS. spectrum. Consider the theoretical method very appropriate to compounds that absorb in vacuum UV.