أجريت هذه الدراسة في محافظة النجف بالعراق لتحليل عينات بيولوجية من المدخنين وغير المدخنين. تم استخدام العينات، بما في ذلك مصل الدم والبول والشعر والأظافر، كمؤشرات حيوية لتحديد تركيزات اليورانيوم (UC) ونظائره (238U، 235U، و234U). وباستخدام طريقة التعرض الطبيعي، تم استخدام كاشف المسار النووي (CR-39، المملكة المتحدة) لقياس تركيزات اليورانيوم في العينات. تم جمع خمسة وسبعين عينة من مصل الدم والبول والشعر والأظافر للمدخنين من الأصحاء وخمسين عينة لغير المدخنين من الأصحاء في خمس فئات عمرية لجميع العينات. اعتمدت هذه الدراسة على العمر والتدخين لمقارنة النتائج وتحديد تأثيرها على تراكيز اليورانيوم. أظهرت النتائج أن متوسط قيم تراكيز اليورانيوم في مصل الدم والبول والشعر والأظافر لدى المدخنين كان 0.180±0.042 جزء في المليون، 0.759±0.024 جزء في المليون، 0.912±0.085 جزء في المليون، و0.934±0.091 جزء في المليون، على التوالي. بينما بلغ متوسط قيم تراكيز اليورانيوم في مصل الدم والبول والشعر والأظافر لدى غير المدخنين 0.110±0.014 جزء في المليون، 0.157±0.023 جزء في المليون، 0.736±0.032 جزء في المليون، و0.756±0.024 جزء في المليون، على التوالي. وتشير النتائج والمقارنات إلى أن جميع تراكيز اليورانيوم تعتمد على المتغيرات التي بنيت عليها هذه الدراسة (العمر والتدخين). وبمقارنة تراكيز اليورانيوم لجميع العينات البيولوجية للمدخنين وغير المدخنين، كانت قيمة P ذات دلالة إحصائية عالية حيث كانت أقل من 0.001. ووفقا لنتائج عينات الدراسة، فإن متوسط قيم UC، 238U، 235U، و234U للعينات البيولوجية لدى المدخنين كانت أعلى منها لدى غير المدخنين. وبالتالي، يمكن القول أن تدخين السجائر يستخدم كمؤشر حيوي لوجود تركيزات اليورانيوم.
This study investigates the implementation of Taguchi design in the estimation of minimum corrosion rate of mild-steel in cooling tower that uses saline solution of different concentration. The experiments were set on the basis of Taguchi’s L16 orthogonal array. The runs were carried out under different condition such as inlet concentration of saline solution, temperature, and flowrate. The Signal-to- Noise ratio and ANOVA analysis were used to define the impact of cooling tower working conditions on the corrosion rate. A regression had been modelled and optimized to identify the optimum level for the working parameters that had been founded to be 13%NaCl, 35ᴼC, and 1 l/min. Also a confirmation run to establish the p
... Show MoreNuclear emission rates for nucleon-induced reactions are theoretically calculated based on the one-component exciton model that uses state density with non-Equidistance Spacing Model (non-ESM). Fair comparison is made from different state density values that assumed various degrees of approximation formulae, beside the zeroth-order formula corresponding to the ESM. Calculations were made for 96Mo nucleus subjected to (N,N) reaction at Emax=50 MeV. The results showed that the non-ESM treatment for the state density will significantly improve the emission rates calculated for various exciton configurations. Three terms might suffice a proper calculation, but the results kept changing even for ten terms. However, five terms is found to give
... Show MoreThe paper uses the Direct Synthesis (DS) method for tuning the Proportional Integral Derivative (PID) controller for controlling the DC servo motor. Two algorithms are presented for enhancing the performance of the suggested PID controller. These algorithms are Back-Propagation Neural Network and Particle Swarm Optimization (PSO). The performance and characteristics of DC servo motor are explained. The simulation results that obtained by using Matlab program show that the steady state error is eliminated with shorter adjusted time when using these algorithms with PID controller. A comparative between the two algorithms are described in this paper to show their effectiveness, which is found that the PSO algorithm gives be
... Show MoreThe consumption of fossil fuels has caused many challenges, including environmental and climate damage, global warming, and rising energy costs, which has prompted seeking to substitute other alternative sources. The current study explored the microwave pyrolysis of Albizia branches to assess its potential to produce all forms of fuel (solid, liquid, gas), time savings, and effective thermal heat transfer. The impact of the critical parameters on the quantity and quality of the biofuel generation, including time, power levels, biomass weight, and particle size, were investigated. The results revealed that the best bio-oil production was 76% at a power level of 450 W and 20 g of biomass. Additionally, low power levels led to enhanced
... Show MoreBackground: Bacteriocin is a peptidic toxin has many advantages to bacteria in their ecological niche and has strong antibacterial activity. Objective: The aim of this study was to evaluation of bacteriocin using Streptococcus sanguinis isolated from human dental caries.
Subjects and Methods: Thirty five streptococcus isolates were diagnosed and tested for their production of bacteriocin, and then the optimal conditions for production of bacteriocin were determined. After that, the purification of bacteriocin was made partially by ammonium sulfate at 95% saturation levels, followed by and gel filtration chromatography
... Show MoreDue to the wide distribution through the Iranian Plateau, especially in its western parts adjacent to Iraq’s northeastern borders, the occurrence of Brandt’s Hedgehog
Excessive intake of fluoride, mainly through drinking water is a serious health hazard affecting humans worldwide. In this study, the defluoridation capacities of locally available raw waste beef bones have been estimated. Several experimental parameters including contact time, pH, bone dose, fluoride initial concentration, bone grains size, agitation rate, and the effect of co-existence of anions in actual samples of wastewater were studied for fluoride removal from aqueous solutions. Results indicated excellent fluoride removal effeciency up to 99.7% at fluoride initial concentration of 10 mg F/L and 120 min contact time. Maximum fluoride uptake was obtained at neutral pH range 6-7. Fluoride removal kinetic was well described by the ps
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