In this work polymeric composites were done from unsaturated polyester as a matrix reinforced with glass fiber type (E-glass) with two different volume fraction 20% & 40%. Fatigue tests showed that the number of fatigue cycles to failure limit for samples reinforced with uniform (woven Roving 0-90°) E-glass fiber and random (continuous fibers) with volume fraction 40% more than that for the same samples with volume fraction 20%. Also the fatigue results showed that the uniform samples failed with fatigue cycles more than that of random.
The adopted accelerated curing methods in the experimental work are 55ºC and 82ºC according to British standard methods. The concrete mix with the characteristics compressive strength of 35MPa is design according to the ACI 211.1, the mix proportion is (1:2.65:3.82) for cement, fine and coarse aggregate, respectively. The concrete reinforced with different volume fraction (0.25, 0.5 and 0.75)% of glass, carbon and polypropylene fibers. The experimental results showed that the accelerated curing method using 82ºC gives a compressive strength higher than 55ºC method for all concrete mixes. In addition, the fiber reinforced concrete with 0.75% gives the maximum compressive strength, flexural and splitting tensile strength for all types of
... Show MoreDe-waxing of lubricating oil distillate (400-500 ºC) by using urea was investigated in the present study. Lubricating oil distillate produced by vacuum distillation and refined by furfural extraction was taken from Al-Daura refinery. This oil distillate has a pour point of 34 ºC. Two solvents were used to dilute the oil distillate, these are methyl isobutyl ketone and methylene chloride. The operating conditions of the urea adduct formation with n-paraffins in the presence of methyl isobutyl ketone were studied in details, these are solvent to oil volume ratio within the range of 0 to 2, mixer speed 0 to 2000 rpm, urea to wax weight ratio 0 to 6.3, time of adduction 0 to 71 min and temperature 30-70 ºC). Pour point of de-waxed oil and yi
... Show MoreABSTRACT Background: This study aimed to study the effect of some acidic drinks (Vinegars and fresh Orange juice) and energy drinks (Red bull) on surface roughness of three types of bulkfill composite materials: Filtek posterior bulkfill (3M), Sonicfill (Kerr) and Filtek p60 (3M). Materials and Methods: Total number of 120 samples are prepared by using a mold of (12mm diameter and 3mm height), which were divided into three groups forty samples for each group: Group A: Filtek bulkfill posterior composite (3M), Group B: Sonicfill composite (Kerr), Group C: Filtek P60 (3 M) which then divided into four sub- groups (n=10) (1) samples were kept in distilled water as a control group (2) samples were immersed in Redbull (3) samples were immersed
... Show MoreIn this search, Ep/SiO2 at (3, 6, 9, 12 %) composites is prepared by hand Lay-up method, to measure the change in the thermal conductivity and Impact Strength of epoxy resin before and after immersion in H2SO4 Solution with a 0.3N for 10 days. The results before immersion decreases with the increase of the weight ratios of the reinforcement material (SiO2), It changed from (82.6×10-2 to 38.7×10-2 W/m.°C) with change weight ratios from (3 to 12) % respectively, but after immersion time in the chemical solution where it was (65.6×10-2 W/m.°C) at the weight ratios (6 %) and became (46.6 × 10-2 W/m.°C) after immersion in sulfuric acid. The results of the Impact strength decreased by increasing the percentage weight ratio, it changed f
... Show MoreAmaranthus viridis (F. Amaranthaceae), usually known as slender amaranth. It is a multifunctional vegetable that grows in tropical and subtropical areas, sustaining stressful conditions, especially drought, producing a wide array of secondary metabolites: phenolics, terpenes, carotenoids and others, which are responsible for various therapeutic effects. Aerial parts were defatted with hexane, then the defatted residue was extracted in the Soxhlet using 80 % aqueous ethanol. Ethanolic extract was sequentially and repeatedly partitioned with solvents of different polarities: chloroform, ethyl acetate and n-butanol. Then, the n-butanol fraction was hydrolyzed using reflex with 10 % aqueous HCl for 6 hrs. The unhydrolyzed and hydrolyz
... Show Moreيعد العلاج الحركي من الوسائل العلاجية التأهيلية من الوسائل المهمة الامنة لأنها تؤمن على حياة الانسان بكافة شؤونه وتعد التمرينات التأهيلية اسلوبا فعالاً وطبيعياً لا تعرض المريض الى مضاعفات على وظائف الجسم الاخرى لأنها خالية من اي دواء كيمياوي ضار ، كما استخدمت تقنيات حديثة في العلاج الطبيعي بشكل واسع معد حسب اسس علمية منها تمرينات (Core) التي تساعد في تخفيف الالام بالانزلاق الغضروفي للفقرة الرابعة والخا
... Show MoreMineral fillers are a fundamental component of asphalt mastic and play a critical role in governing the mechanical performance and durability of flexible pavements. Variations in filler type and dosage can substantially alter mastic stiffness, deformation resistance, fatigue behavior, and adhesion. The objective of this study is to systematically evaluate the influence of mineral filler type and filler-to-asphalt (F/A) ratio on the rheological, fatigue, and adhesive performance of asphalt mastics. Three commonly used fillers; limestone dust, Portland cement, and hydrated lime were investigated at four F/A ratios (0.6, 0.8, 1.0, and 1.2). A comprehensive experimental program was conducted, including conventional binder characterization, Mult
... Show MoreWater flow into unsaturated porous media is governed by the Richards’ partial differential equation expressing the mass conservation and Darcy’s laws. The Richards’ equation may be written in three forms,where the dependent variable is pressure head or moisture content, and the constitutive relationships between water content and pressure head allow for conversion of one form into the other. In the present paper, the “moisture-based" form of Richards’ equation is linearized by applying Kirchhoff’s transformation, which
combines the soil water diffusivity and soil water content. Then the similarity method is used to obtain the analytical solution of wetting front position. This exact solution is obtained by means of Lie’s