Rutting is one of the major distresses in pavement. The objective of this paper is to develop an improved asphalt binder grading system for Iraq based on the principal of Superpave system, and increasing performance grade of product asphalt binder in Iraq using polymers without raising the viscosity of the binder. Two types of polymers are used, Plastomers, Functionalized Polyethylene (PE) which is developed by asphalt research group in Wisconsin University in the USA, and Elastomers, Styrene Butadiene Styrene (SBS) with and without cross linker. Mastercurve are drown for these modified binders, Rolling thin film aged, to show effects on rheological properties at high temperature for complex modulus (G*) and phase angle (δ). It concluded that 3.5% of Functionalized Polyethylene polymer (PE) is more effective than 4% of Styrene Butadiene Styrene (SBS) to shift up performance grade of local asphalt binder two grades to be PG (76-16). Furthermore, the viscosity of binders increasing about 200% when using 4 % SBS, while no significant effect on viscosity when using 3.5 % of PE, therefore, there is no need to increase temperature of mixing and compaction which may be effect on polymers In addition G*/sinδ is increased by a ratios of 1.6 to 2.96 for 2%, 4% respectively of SBS-based modifier (RTFO aged) and 1.4 to 3 for 2%, 3.5% respectively of PE-based polymers modifier. It can be seen that PE reduce G*.sinδ about 10%, while SBS increase G*.sinδ about 30% and PE reduces the stiffness of asphalt binder about 15 % at low temperature which make PE more effective, there is no significant effects on m-value.
Double hydrothermal method was used to prepare nano gamma alumina using aluminum nitrate nano hydrate and sodium aluminate as an aluminum source, CTAB (cetyltrimethylammonium bromide) as surfactant, and variable acids: weak acids like; citric, and acitic acids, and strong acids like; hydrochloric and nitric acids as a bridge between aluminum salts and surfactant. Different crystallization times 12, 24, 48, and 72 hrs were applied. All the batches were prepared at pH equals to 9. XRD diffraction technique was used to investigate the crystalline nano gamma alumina pure from surfactant. N2 adsorption-desorption (BET) was used to measure the surface area and pore volume of the prepared nano alumina, the average p
... Show MoreRooting response in stem cuttings of mung bean increased considerably with inresing
seedling age, due to endogenous IAA or supplied IBA. However, after the day 7- or 8-old of
seedling age. The cotyledons sheivel and drop-off spontaneously at day-8 of seedling age. So
that cotyledons excision after cuttings were made during the period between seedling
emergence (the day 4) and cotyledons dropping off (which starts at day 8 and its completion
at day 10) causes decrease in rooting at any time during cutting treatment ,in particular, at
zero time . In addition, results of this study revealed that terminal buds do not influence
significantly adventitious root formation whether IBA supplied or not. Whereas in leafless
c
In this work, Titanium oxide thin films doped with different concentration of CuO (0,5,10, 15,20) %wt were prepared by pulse laser deposition(PLD) technique on glass substrates at room temperature with constant deposition parameter such as : pulse (Nd:YAG), laser with λ=1064 nm, constant energy 800 mJ , repetition rate 6 Hz and No. of pulse (500). The structure , optical and electrical properties were studied . The results of X-ray diffraction( XRD) confirmed that the film grown by this technique have good crystalline tetragonal mixed anatase and rutile phase structure, The preferred orientation was along (110) direction for Rutile phase. The optical properties of the films were studied by UV-VIS spectrum in the range of (360-1100)
... Show MoreIn this work, we study the effect of doping Sn on the structural and optical properties of pure cadmium oxide films at different concentrations of Tin (Sn) (X=0.1,0.3 and 0.5) .The films prepared by using the laser-induced plasma at wavelength of laser 1064 nm and duration 9 ns under pressure reached to 2.5×10-2 mbar. The results of X-ray diffraction tests showed that the all prepared films are polycrystalline. As for the topography of the films surface, it was measured using AFM , where the results showed that the grain size increases with an increase in the percentage of doping in addition to an increase in the average roughness. The optical properties of all films have also been studied through the absorbance s
... Show MoreBackground: Separation and deboning of artificial teeth from denture bases present a major clinical and labortory problem which affect both the patient and the dentist. The optimal bond strength of artificial teeth with denture base reinforced with nanofillers and flexible denture bases and the effect of thermo cycling should be evaluated. This study was conducted to evaluate and compare the shear bond strength of artificial teeth (acrylic and porcelain) with denture bases reinforced by 5% Zirconium oxide nanofillers and flexible bases under the effect of different surface treatments and thermo cycling and comparing the results with conventional water bath cured denture bases. Material and methods: Two types of artificial teeth; acrylic and
... Show MoreUnderstanding the effects of fear, quadratic fixed effort harvesting, and predator-dependent refuge are essential topics in ecology. Accordingly, a modified Leslie–Gower prey–predator model incorporating these biological factors is mathematically modeled using the Beddington–DeAngelis type of functional response to describe the predation processes. The model’s qualitative features are investigated, including local equilibria stability, permanence, and global stability. Bifurcation analysis is carried out on the temporal model to identify local bifurcations such as transcritical, saddle-node, and Hopf bifurcation. A comprehensive numerical inquiry is carried out using MATLAB to verify the obtained theoretical findings and und
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