The wide use of lead compounds as an engine anti-knock reflects conversely on all components of the ecosystem. This study aimed to detect the concentration of lead in various types of gasoline and gas oil that are highly consumed by vehicles. Eight fuel samples were collected from different feul stations distributed in different districts of Baghdad city. These included two gas oil (diesel) stations and three stations for each type of gasoline (leaded and unleaded). Lead was extracted by the modified chemical method, and then flame atomic absorption technique was applied to assay its concentrations. The results indicated that lead levels were within permitted limits (150 mg Lead L-1) recommended by the international agencies. The highest lead mean concentration was 105 mg/L, recorded in Latifiya leaded gasoline, whereas the lowest mean was 3.1mg/L in unleaded gasoline imported from the United Arab Emirate. As for gas oil, lead concentration occurred within a mean of 1.85-2.05 mg/L. The influence of some leaded gasoline improvements, octane booster and octane plus, was estimated, which revealed sharp declines in lead mean concentrationsto values of 1.05 and 5.2 mg/L for Latifiya and Rusafa gasoline, respectively. Furthermore, the daily lead emission was estimated for the registered vehicles in Baghdad and revealed a high concentration of 1837.7 µg lead m-3 for private cars. This study proposes avoiding the addition of lead compounds to fuel, in order to reduce its adverse effects on general health, and raising the awareness of society to this problem.
Effect of [Cu/In] ratio on the optical properties of CuInS2 thin films prepared by chemical spray pyrolysis on glass slides at 300oC was studied. The optical characteristics of the prepared thin films have been investigated using UV-VIS spectrophotometer in the wavelength range (300-1100 nm). The films have a direct allow electronic transition with optical energy gap (Eg) decreased from 1.51 eV to 1.30 eV with increasing of [Cu/In] ratio and as well as we notice that films have different behavior when annealed the films in the temperature 100oC (1h,2h), 200oC (1h,2h) for [Cu/In]=1.4 . Also the extinction coefficient (k), refractive index (n) and the real and imaginary dielectric constants (ε1, ε2) have been investigated
This study aims to fabricate and assess the β-tricalcium phosphate (β-TCP) bioactive ceramic coat layer on bioinert ceramic zirconia implants through the direct laser melting technique by applying a long-pulsed Nd:YAG laser of 1064 nm. Surface morphologies, adherence, and structural change in the coatings were evaluated by optical microscopy, field emission scanning electron microscope, hardness, and x-ray diffractometer. The elastic modulus (EM) of the coating was also determined using the nanoindentation test. The quality of the coating was improved when the laser power was 90 W with a decrease in the scan speed to 4 mm s−1. The chemical composition of the coat was maintained after laser processing; also, the Energy Dispersive
... Show MorePurpose: clarify the integrative relationship of strategic leadership skills and effective management and the role of those skills combined or individually in achieving effective management.
Research design: The researchers used the quantitative method by surveying a class sample from the heads of the executive departments in a group of Iraqi private banks, consisting of (106) individuals according to the (VUCA Prime) methodology for effective management and the ten skills model for Johansen. The questionnaire was analyzed using a model of the structural equation.
Findings: The most prominent results of the research were the presence of a weak ro
... Show MoreIn this work, the annual behavior and cross-correlation between three different solar-ionospheric indices were evaluated: Smoothed Sunspot Number (SSN), Ionospheric T-Index (T-index), and Solar Flux (F10.7 cm) index during solar cycles 23 and 24. The annual behavior for the three tested indices of the maximum and minimum years of the two solar cycles was studied. The correlative conducts between the studied indices were evaluated for the studied periods (1996-2008) and (2008-2019) of the 23rd and 24th solar cycles. The annual correlation between the studied indices was represented by the linear regression equation. The suggested mutual correlation equation gave a good agreement with the observed annual average values of the test
... Show More