This study includes the manufacture of four ternary alloys represented S60Se40-XPbX with weight ratios x = 0, 10, 20, and 30 by the melting point method. The components of each alloy were mixed separately, then placed in quartz ampoules and vacuumed out with a vacuum of roger that 10−4 Torr. The ampule was heated in two stages to avoid sudden dissipation and precipitation of selenium on the inner mass of the quartz tube. The ampoule was gradually heated and kept at 450°C for approximately 4 hours followed by 950°C for 10 hours.at a rate of 10 degrees Celsius, the temperature of the electric furnace was increased, and then the ampoule was subjected to rapid cooling with cold water to reach a state of solidity glass-like. The research aims to investigate the effect of adding lead to selenium on the properties of thermal conductivity and heat flux density. It has been noted that the partial replacement of selenium with lead affected these properties significantly.
Abstract: The aim of this study is to assess the effectiveness of 940 nm diode laser in comparison to Endoactivator in elimination of smear layer in terms of radicular dentin permeability and ultra-structural changes of root canal walls by SEM evaluation. Twenty-eight single-rooted extracted lower premolars were instrumented up to size X4 (protaper Next, Dentsaply) and divided into two experimental groups according to the irrigation system, G1; activated by EndoActivator and G2; activated by Diode laser 940 nm, CW mode, 1.7 W. Afterward, the roots were made externally impermeable, filled with 2%methylene blue dye, divided horizontally into three segments representing the apical, middle, and coronal thirds then examined under stereo- micr
... Show MoreThe research aims to measure the impact of the quality of the audit on the Earnings Quality, for a sample of private joint stock companies listed on the Iraq Stock Exchange, as the research sample included (14) private and listed joint stock companies in issuing their financial statements for the period from (2010-2018), as well as companies The audit offices in charge of auditing these companies, which number (18) companies or an audit office, and the research relied on two main models for measurement, as the first model reflects the assumed relationship between independent variables represented in the characteristics of external audit quality and measuring the extent of its impact on the dependent variable represented in the Ea
... Show Morehe present work, among other previous studies done in our lab, aimed to highlight the histopathological effect of S. xylosus peptidoglycan in comparison to LPS of E. coli. Materials and methods: One hundred and fifty urine specimens were collected from urinary tract infection patients visiting Baghdad hospitals. The histopathological effects of S. xylosus S24 peptidoglycan was studied in the urinary tract of female mice by injecting 5 animal groups at the following concentrations: 1000, 2000, 3000, 4000, and 5000 µg/mL. Another 5 groups were injected with 10, 25, 50, 75, and 100 ng/mL of E. coli (serotype 0128:B12) LPS. Results: Ten isolates were confirmed to be Staphylococcus xylosus. Histopathological study showed different pathological
... Show MoreLead acetate as one of the environmental pollutants can threats the life of living creatures in many ways, it has a long half-life, accumulates mainly in the soft tissue and leads to adverse effects in these tissues. An experiment was conducted to study the effect of oral feeding of lead acetate on histological features of liver, kidney, testis and muscle of albino mice. Mice were treated with 0.05 mg/100 ml lead acetate (LA) for 10 days (group A) and for and for 20 days (group B) and for 30 days (group C). The histological section of liver of mice group A characterized by slightly blurred trabecular structure with foci of hepatitis which increased with cytoplasmic vacules in group B but in group C liver reveal necrosis, heamorrhage,
... Show MoreNuclear shell model is adopted to calculate the electric quadrupole moments for some Calcium isotopes 20Ca (N = 21, 23, 25, and 27) in the fp shell. The wave function is generated using a two body effective interaction fpd6 and fp space model. The one body density matrix elements (OBDM) are calculated for these isotopes using the NuShellX@MSU code. The effect of the core-polarizations was taken through the theory microscopic by taking the set of the effective charges. The results for the quadrupole moments by using Bohr-Mottelson (B-M) effective charges are the best. The behavior of the form factors of some Calcium isotopes was studied by using Bohr-Mottelson (B-M) effective charges.
In this study; a three-dimensional model was created to simulate groundwater in Al-Haydariyah area of the governorate of Al-Najaf. A solid model was created to utilize the cross sections of 25 boreholes in the research region, and it was made out of two layers: sand and clay. The steady-state calibration was employed in six observation wells to calibrate the model and establish the hydraulic conductivity, which was 17.49 m/d for sand and 1.042 m/d for clay, with a recharge rate of 0.00007 m/day. The wells in the research region were reallocated with a distance of 1500 m between each well, resulting in 140 wells evenly distributed throughout the study area and with a discharge of 5 l/s, and the scenarios were run for 1000
... Show MoreThe study was carried out in plant tissue culture laboratory, University of Baghdad during the period 2017-2019, as factorial experiment in complete randomized design, to study the effect of PEG at (0, 2, 4, 6 and 8%) on physiological and chemical changes in callus of three sunflower (Ishaqi 1, Aqmar and Al-haga) induced by the cultivation of the young stem in vitro under water stress. The content of callus cells of SOD, POD, CAT and APX enzymes as well as content of hydrogen peroxide were determined as indicators to determine the effect of PEG in callus tissue cells cultivated on medium equipped with the PEG concentrations. The results showed that cultivars were differs significantly and Al-hajavariety was superior in increasing SOD to 24.
... Show MoreDiscrete logarithms are applied in many cryptographic problems . For instance , in public key . and for construction of sets with disti nct sums of k-clcments. The purpose o r this paper
is to modify the method ol' informationl1·iding using discrete logarithms , introduce new properties of St - sets , uscdthe direct product of groups to construct cyclic group and finally, present modified method for knapsack &
... Show MoreAn experimental and numerical study was carried out to investigate the heat transfer by natural convection in a three dimensional annulus enclosure filled with porous media (silica sand) between two inclined concentric cylinders with (and without) annular fins attached to the inner cylinder under steady state condition. The experiments were carried out for a range of modified Rayleigh number (0.2 ≤Ra*≤ 11) and extended to Ra*=500 for numerical study and for annulus inclination angle of (δ = 0˚, 30˚, 60˚ and 90˚). The numerical study was to give the governing equation under assumptions that used Darcy law and Boussinesq’s approximation and then it was solved numerically using finite difference approximation. It was found that t
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