The permanent deformation of flexible pavement represent serious problem in hot climate region. Numerous efforts are devoted to mitigate this distress such as modifying asphalt binder by polymers. The present study demonstrate the effect of utilizing four types of polymers to reduce the permanent deformation, these polymers are Polyethylene Wax (PEW), Styrene Butadiene Rubber (SBR), Ethylene Propylene Dien Monomer (EPDM) and Ethylene Vinyl Acetate (EVA). The prepared mixtures composed of 4.9 % of 40/50 asphalt binder, 12.5 mm nominal aggregate maximum size and limestone dust as filler. The permanent and resilient strains have been recorded when the cylindrical specimens, 101.6 mm in diameter and 203.2 mm in height, tested by repeated loading system. The main conclusions exhibit that SBR and EPDM with the same concentration (15 % by weight of asphalt binder) reduced the permanent deformation by 30.20 % and 30.46 % respectively. Although, the PEW and EVA reduced permanent deformation by lower values, 13.24 % and 17.35 % respectively, but the incremental percentage of their action are higher. The influences of testing temperature and stress level on permanent deformation were investigated. Linear regression model was established to correlate the values of permanent deformation and the resilient modulus of asphalt mixtures.
Background and purpose: Animal model helps researchers to evaluate new treatment plan for human and understand pathological mechanism involved in a development of disease. The use of rats as an animal model for Alzheimer's research has become a favorite among researchers. Rats are capable in mimicking Alzheimer disease due to their intelligence and quick adaptation to nature. At present there are several methods that can be used to induce Alzheimer's animals, but each method has advantages and disadvantages. We need to learn other methods that can provide many advantages and few disadvantages. The Amyloid-beta 42 (Aβ-42) and Reactive Oxygen Species (ROS) are thought to play an important role in the pathology of Alzheimer’s disease. Th
... Show MoreEuphrates River extends about 125 km within the study area located in Annassiriyah City, Dhi Qar Governorate, Iraq. The impact of the seven hydraulic structures on the discharge capacity of the Euphrates River needs to be considered. The main objectives of this research are to increase the discharge capacity of Euphrates River within Annassiriyah City during flood seasons and study the impact of these hydraulic structures on the river capacity by using HEC-RAS 5.0.3 software. Five scenarios were simulated to study the different current condition of Euphrates River within Annassiriyah City. Other additional four scenarios were implemented through river training to increase the river capacity to 1300 m³/s; it is the flood
... Show MoreThe research aimed at designing a teaching aid for learning backswing into handstand as well as identifying its effect on learning skill performance. The researchers hypothesized statistical differences between pre and post-tests in favor of the research group. They used the experimental method on six (13 – 16) year–old Baghdad club gymnasts. The researchers used the one group design in which all players perform pretests followed by special tests on the teaching aid than are tested posttests. The researchers conclude that the teaching aid positively affected learning the skill as well as the teaching aid was very good and endured the performance of all gymnasts. The researcher recommended making simi
... Show MoreBackground: myocardial ischemia-reperfusion (I/R) injury may occur in a variety of clinical settings and this remains a significant problem. Oxygen free radicals, produced on reperfusion have been shown to play a major role in myocardial I/R injury. Various therapeutic effects have been described for Crataegus. Additionally, it has been presented that Crataegus has protective effect against ischemia reperfusion induced myocardial injuries to various organs. Therefore, it seems possible that the administration of Crataegus might protect the heart against the ischemia reperfusion injury.
Objectives: I detected the chemical components and trace elements of the aqueous extract of Crataegus leaves and determine whether Crataegus extract pr
In this work, a composite material was prepared from Low-density polyethylene (LDPE) with different weight percent of grain and calcinations kaolin at temperature of (850oC) using single screw extruder and a mixing machine operated at a temperature between (190-200oC). Some of mechanical and physical properties such as tensile strength, tensile strength at break, Young modulus, and elongation at break, shore hardness and water absorption were determined at different weight fraction of filler (0, 2, 7, 10 and 15%). It was found that the addition of filler increases the modulus of elasticity, elongation at break, shore hardness and impact strength; on other hand, it decreases the tensile strength and tensile strength
... Show MoreIn this study, the response and behavior of machine foundations resting on dry and saturated sand was investigated experimentally. A physical model was manufactured to simulate steady state harmonic load at different operating frequencies. The effect of relative density, depth of embedment, foundation area as well as the imposed harmonic load was investigated. It was found that the amplitude of displacement of the foundation increases with increasing the amplitude of dynamic force and operating frequency meanwhile it decreases with increasing the relative density of sand, degree of saturation, depth of embedment and contact area of footing. The maximum displacement was noticed at 33.34 to 41.67 Hz. The maximum displaceme
... Show MoreAn investigation was conducted for dewaxing of lubricating oil fraction by urea to reduce the pour point.In this study mixture of 45 % methyl ethyl ketone (MEK) and 55 % toluene was used as a solvent. The studied variables are mixing time (10-70 min), solvent to oil volume ratio (0.5:1- 2:1), urea to wax weight ratio (2- 6) and constant mixing speed 1500 rpm. By analysis of the experimental results, the best operating conditions achieved are mixing time 40 min, solvent/oil 2:1 volume ratio, and urea/wax 4:1 weight ratio. At these conditions the pour point of the lubricating oil decreases from 24 ° C to -13 °C.
The current study dealt with the effect of water extract of pomegranate peel plant on Oscillatoria amoena growth that isolated from Diwaniya river, The effect of the pomegranate extract was measured by calculating the total number of cells and the absorbance values of the alga. Three concentrations were used 3.5, 7 and 14 mg/ml from extract of pomegranate fruit peel in addition to the control group. The results showed that exposing the alga to concentrate 14 mg/ml led to lower growth sharply, while the rest of the concentrations 3.5 and 7 mg/ml also decreased the growth gradually. The absorbance values showed a decline similar to the number of cells during the period of the exposure.
In the current study, we investigate the effect of (La) substitution instead of (Cu) on the properties of the superconductor compound (Bi2Sr2Ca2Cu3-xLaxO10+δ) with (x=0,0.05,0.1,0.15,0.2). The samples were prepared by solid state reaction method(SSR). Xray diffraction technique (XRD) was used to estimate the structural properties of the specimens which show an orthorhombic crystalline structure for all the specimens. The results show that the change in ( La) concentration leads to decrease the concentration of (Bi-2223), increment in (Bi-2212 ) and(Bi-2201) with appearance of some impurities. Also decrease the critical temperature(Tc) with the increase
... Show MoreA factorial experiment (2× 3) in randomized complete block design (RCBD) with three replications was conducted to examine the effect of honeycomb selection method using three interplant distances on yield and its components of two cultivars of bean, Bronco and Strike. Interplant distances used were 75× 65 cm, 90× 78 cm, and 105× 91 cm (row× plant) represent short (high plant density), intermediate (intermediate plant density), and wide (low plant density) distance, respectively. Parameters used for selection were number of days from planting to the initiation of first flower, number of nodes formed prior to first flower, and number of main branches. Results showed significant superiority of the Bronco cultivar represented in the number
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