Two grades of paving asphalt with penetration of 46 and 65 are studied for determining changes in their physical and chemical properties caused by ageing.
The ageing process has been conducted on two petroleum paving asphalt cement using thin film oven test at 150, 163 and 175 C, and ageing time 5, 10,15, 20, 25 and 30 hours. The effect of ageing time and temperature on penetration, kinematic viscosity, softening point, solubility in trichloroethylene, heat loss and changes in chemical composition are investigated. The results of thin film oven test process indicte that the asphaltenes concentration of all aged asphalt increases with increasing ageing time, while the opposite was observed for polar-aromatic and naphthene-aromatic. The saturate of low penetration grade asphalt is higher than that for high penetration grade asphalt and remained unchanged with ageing time. Th kinematic viscosity and softening point seem to increase with increasing ageing time, while the penetration decreases with increasing ageing time. The DI of aged asphalt inreases with increasing ageing time.
This research aims to test the effect of strategic cohesion with its dimensions (organizational excitement, organizational casting, organizational synergy) as an independent variable on administrative excellence as a dependent variable in the Ministry of Planning, and through surveying several employees (general managers, heads of departments, and units managers). As a research community, and based on the importance of the research topic in the aforementioned research community. The researchers have adopted the descriptive-analytical using the questionnaire as the main data collection. 155 questionnaires were distributed, yet,114 of them were retrieved and 110 were used for final statistical analysis. The researchers used the relev
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Receipt date:11/19/2020 acceptance date:10/1/2021 Publishing date:12/31/2021
This work is licensed under a Creative Commons Attribution 4.0 International License.
Human rights are one of the basic concepts of modern and contemporary times, and political thought as the origin of political science and its source of knowledge have impact in this science and its branches
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Irrigation has significant role in endodontic treatment, many types of antimicrobial irrigation solutions have been used, but due to the ineffectiveness, safety concerns and side effects of this irrigation, the herbal alternatives for endodontic irrigants might be beneficial. Objectives This study compared the in vitro effectiveness of tea tree oil and clove oil as possible irrigants in endodontics against Enterococcus faecalis in comparison with 3% Sodium hypochlorite. Materials and Methods E. faecalis was isolated from patients in need for endodontic treatment; VITEK was employed for E. faecalis isolate conformation. Muller Hinton agar was prepared with 100μl of freshly prepared suspension of E.faecalis. Wells of 6mm diameter and 4mm dep
... Show MoreIrrigation has significant role in endodontic treatment, many types of antimicrobial irrigation solutions have been used, but due to the ineffectiveness, safety concerns and side effects of this irrigation, the herbal alternatives for endodontic irrigants might be beneficial. Objectives This study compared the in vitro effectiveness of tea tree oil and clove oil as possible irrigants in endodontics against Enterococcus faecalis in comparison with 3% Sodium hypochlorite. Materials and Methods E. faecalis was isolated from patients in need for endodontic treatment; VITEK was employed for E. faecalis isolate conformation. Muller Hinton agar was prepared with 100μl of freshly prepared suspension of E.faecalis. Wells of 6mm diameter and 4mm dep
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(2)
The δ-mixing ratios have been calculated for several γ-transitions in 90Mo using the 𝛔 𝐉 method. The results are compared with other references the agreement is found to be very good .this confirms the validity of the 𝛔 𝐉 method as a tool for analyzing the angular distribution of γ-ray. Key word: population parameter, γ-ray transition, 𝛔 𝐉 method, multiple mixing ratios.
Nanostructure of chromium oxide (Cr2O3-NPs) with rhombohedral structure were successfully prepared by spray pyrolysis technique using Aqueous solution of Chromium (III) chloride CrCl3 as solution. The films were deposited on glass substrates heated to 450°C using X-ray diffraction (XRD) shows the nature of polycrystalline samples. The calculated lattice constant value for the grown Cr2O3 nanostructures is a = b = 4.959 Å & c = 13.594 Å and the average crystallize size (46.3-55.6) nm calculated from diffraction peaks, Spectral analysis revealed FTIR peak characteristic vibrations of Cr-O Extended and Two sharp peaks present at 630 and 578 cm-1 attributed to Cr-O “stretching
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(3)
The goal of our study is to perform detailed multiband surface photometry of the spiral galaxy NGC 4448 and its brightest star-forming regions. The structure and composition of the stellar population in the surface brightness galaxy NGC 4448 was studied using BVR CCD photometry. The observations were obtained on the 1.88 m optical telescope of Kottamia Astronomical Observatory (KAO), Egypt. A two-dimensional decomposition of the galaxy bulge and disk components is carried out. A powerful star forming region is observed near the galactic center. Based on the positions of the various components of the galaxy in two color diagrams. From the observations, the surface brightness profiles, Ellipticity profiles, position angle profiles and colo
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