Tests were performed on asphalt concrete specimens with (101.6 mm in diameter and 101.6 mm in height), and the results were implemented for calculating permanent deformation and resilient modulus under repeated compressive stress with different levels of stresses (0.068, 0.138 and 0.206) MPa at 40 ºC. Two types of additives namely (carbon black-asphalt) and (SBR-asphalt) were tried as rejuvenators with three percentages of (0.5, 1 and 1.5) % by weight of asphalt cement along with two ratios of AC (1 and 2) % have been implemented as rejuvenator and blended with the reclaimed asphalt concrete. Aged materials were obtained from the site. 100% Reclaimed Asphalt Pavement material from the reclaimed mixture is implemented. A set of (3) specimens were prepared for every mixture; three specimens were tested under (repeated compressive stress) at each level of stress. The objective of this work was to study the effect of two types of additives (Styrene-Butadiene-Rubber (SBR) and carbon black) on the performance of recycled asphalt concrete mixture. It was concluded that the Resilient modulus (Mr) at (0.138 and 0.206) MPa stress level decreases by (14, 22 and 8) % and (22, 34 and 11) for reclaimed and recycle mixtures with (carbon black-asphalt and SBR-asphalt) respectively when compared with that at 0.068 MPa. Permanent deformation for recycled mixtures with (carbon black-asphalt and SBR-asphalt) increased by (65.9, 4.54) %, (146.6, 27.2) % and (79, 5.5) % at level of stresses (0.068, 0.138 and 0.206) MPa respectively when compared to reclaimed mixture.
The Effect of Chicken Eggshell Extract on Microhardness of Artificially Induced Dental Erosion in Permanent Teeth (In Vitro Study), Shatha A Abbas*, Alhan A Qasim
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 phas
... Show MoreThis research aims to investigate the effect of four types of nanomaterial on the Marshall properties and durability of warm mix asphalt (WMA). These types are; nano silica(NS), nano carbonate calcium (NCC), nano clay(NC), and nanoplatelets (NP). For each type of Nanomaterial, three contents are tried as following; NS(1%, 3%, and 5%), NCC(2%, 4%, and 6%), NC(3%, 5%, and 7%), and NP (2%, 4%, and 6%) by weight of asphalt cement. Following Marhsall mix design method, the optimum asphalt cement content is determined, thereafter the optimum dosage for each nanomaterial is obtained based on the highest Marshall stability value. The durability of the control mix (no nanomaterial) and modified mixtures have been compared based on moisture damage, r
... Show MoreIn recent years, nano-modified asphalt has gained significant attraction from researchers in the design of asphalt pavement fields. The recently discovered Titanium dioxide nanoparticles (TiO2) are among the most exciting and promising nanomaterials. This study examines the effect of 1, 3, 5, and 7% of nano-TiO2 by weight of asphalt on some of its rheological and hardened properties. The experimental study included physical and rheological properties. The asphalt penetration, softening point, ductility, and rotational viscometer tests indicate that 5% nano-TiO2 is the ideal amount to be added to bitumen as a modifier. The
The loss of dental hard tissue as a result of odontoclastic activity is known as root resorption. It is unwanted and pathological in permanent teeth. Root resorption may happen within the root canal called internal root resorption or on the outer surface of the root called external root resorption. Regardless of where it occurs, root resorption is irreparable, can cause pain for the patient, necessitates treatment, and in some circumstances, resulting in the early loss of the affected tooth. It might be challenging to precisely diagnose and treat root resorption. There is limited information within literatures on root resorption therefore this review aims to understand the radiological and clinical characteristics of r
... Show MoreDuring the last few years, the greener additives prepared from bio-raw materials with low-cost and multifunctional applications have attracted considerable attention in the field of lubricant industry. In the present work, copolymers derived from sunflower and linseed oils with decyl methacrylate were synthesized by a thermal method using benzoyl peroxide (BPO) as a radical initiator. Direct polymerization of fatty acid double bonds in the presence of a free radical initiator results in the development of environmentally friendly copolymeric additives (Co-1 and Co-2). Fourier Transform Infrared (FTIR) and Proton Nuclear Magnetic Resonance (1H-NMR) were used to characterize the resulting copolymers. Thermal decomposition of copolymers was de
... Show MoreIntroduction: Syphilis is a sexually transmitted disease, that may be transferred from mothers to infants during pregnancy if it is left untreated. Method: This study was conducted among 65 women who suffered from recurrent abortions in Iraq. Syphilis screening recombinant (IgM + IgG) level by ELISA, RADIM (Italy) and rapid plasma reagin (RPR) (positive and negative results) tests were used to analyse the data. Results: A non-significant association was observed with age (p=0.989), and the number of healthy births (p=0.643). Non-significant differences were observed in comparisons between smoker and non-smoker percentages in the study group. The rapid test for syphilis confirmation was applied using Rapid Plasma Reagin (RPR) tests.
... Show More- baumannii is an aerobic gram negative coccobacilli, it is considered multidrug resistance pathogen (MDR) and causes several infections that are difficult to treat. This study is aims to employ physical methods in sterilization and inactivation of A. baumannii, as an alternative way to reduce the using of drugs and antibiotics.
Cold Atmospheric Plasma was generated by one electrode at 20KV, 4 power supply and distance between electrode and sample was fixed on 1mm. A. baumannii (ATCC 19704 and HHR1) were exposed to Dielectric Barrier Discharge type of Cold Atmospheric Plasma (DBD-CAP) for several periods
Materials recycling has a significant economic and environmental impact; as a result, steel, aluminium, plastic, and other recyclable materials have been pushed for use in construction materials. One of these recyclable materials is the crumb rubber, has been considered as a pavement component. The general behaviour of the composite rubber-hot mix asphalt system would be varied from that of the conventional rubber free mix. In this review, desirable characteristics of hot mix asphalt are highlighted first. Also, effect of gradation and the main types of rubber are specified. Afterward, many studies that considered the crumb rubber as a waste product and its associated mixture and modifiers are reviewed. The factors affect the crumb
... Show MoreThe growing demand for energy, coupled with the continued dominance of fossil fuels as the primary energy source, necessitates eco-friendly technologies that simultaneously enhance oil recovery (EOR) and reduce the impact of their emissions. Only one task, which is the CO2-EOR project, can combine these two sustainable development goals. Further, employing green nanotechnology, including nanoparticles and nanofluids, ensures a sustainable approach to controlling and enhancing rock wettability, thereby enhancing hydrocarbon production and carbon storage. However, the performance of nanofluids in subsurface formations is limited by the stability of these nano-dispersions at the harsh conditions of reservoirs. This work thus synthesize
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