Frequently, load associated mode of failure, rutting and fatigue, are the main failure types found in some newly constructed roads within Baghdad, the capital of Iraq, and some suburban areas. The use of excessive amount of natural sand in asphalt concrete mixes which is attractive to local contractors could be one of the possible causes to the lack of strength properties of the mixes resulting in frustration in the pavement performance. In this study, the performance properties of asphalt concrete mixes with two natural sand types, desert and river sands, were evaluated. Moreover, five replacement rates of 0, 25, 50, 75, and 100% by weight of the fine aggregate finer than 4.75 were used. The performance properties including moisture susceptibility, resilient modulus, permanent deformation, and fatigue characteristics were evaluated using indirect tensile strength, uniaxial repeated loading and repeated flexural beam tests. Also, as a part of the research objective, the laboratory tests result were used to predict the performance using VESYS computer software. Results showed that mixes with high natural sand content (NSC) are more susceptible to moisture damage and rutting, lower resilient modulus and some improvement in fatigue resistance. Based on the obtained results, the necessity has rise to revise the current local specification for asphalt concrete which specifies the limits of natural sand content in the mixes of wearing and binder courses with 25% whereas for base course mixes no limit exist yet.
This study aimed to conduct a comparative analysis of seven calliphorid species of third- instar larvae that were collected from central Iraq. The purpose was to morphologically characterize these species and develop an identification key to differentiate them from closely related species. Scanning Electron Microscope (SEM) graphical images and high-resolution traditional optical microscopes were used to analyze the morphological characteristics of the species Calliphora vomitoria (Linnaeus, 1758), C. vicina Robineau-Desvoidy, 1830, Chrysomya albiceps (Widemann, 1819), Ch. rufifacies (Macquart, 1844), Ch. megacephala (Fabricius, 1794), Lucilia cuprina (Wiedemann, 1830), and L. sericata (Meigen, 1826). An identification key was const
... Show MoreLipase enzyme has attracted a lot of attention in recent years because of its diverse biotechnological applications. The present study was conducted to screen germinated seeds of four crops, namely sunflower (Helianthus annuus), flaxor linseed (Linum usitatissimum ), peanut (Arachis hypogaea ) and castor bean (Ricinus communis), for the activity of their lipases. to the study also included the extraction and purification of lipase from the seeds of the most promising crop using different solvents. The results indicated that the maximum enzymatic activity (0.669 U/ml) was obtained when 0.1 M Tris-HCl buffer extract was used after 3 days of seed germination of all the tested species, as compared to the other test solvents
... Show MoreBackground: Atrophic postoperative and traumatic scarring are common cosmetic problems for patients. Combining CO2 laser ablation with a fractional photothermolysis system in a treatment known as ablative fractional resurfacing fulfilling the new demands for a lesser risk of side effects and minimal or no downtime.Objective: To assess the safety and efficacy of ablation fractional CO2 laser treatments for surgical scarring .methods: Twenty one patient ( 14 women, and 7 men ) with various skin types , I to IV , aged 3 to 48 years , presents with 24 scars between June and December 2012 , four patients excluded from study because they are not continued in follow up , the remaining 17 patient completed all 3 treatments & 6 months follow
... Show MoreThis work deals with determination of optimum conditions of direct diffusion bonding welding of austenitic stainlesssteel type AISI 304L with Oxygen Free High Conductivity (OFHC) pure copper grade (C10200) in vacuum atmosphere of (1.5 *10-5 mbr.). Mini tab (response surface) was applied for optimizing the influence of diffusion bonding parameters (temperature, time and applied load) on the bonding joints characteristics and the empirical relationship was evaluated which represents the effect of each parameter of the process. The yield strength of diffusion bonded joint was equal to 153 MPa and the efficiency of joint was equal to 66.5% as compared with hard drawn copper. The diffusion zone reveals high microhardness than coppe
... Show MoreThe Pulse Coupled Oscillator (PCO) has attracted substantial attention and widely used in wireless sensor networks (WSNs), where it utilizes firefly synchronization to attract mating partners, similar to artificial occurrences that mimic natural phenomena. However, the PCO model might not be applicable for simultaneous transmission and data reception because of energy constraints. Thus, an energy-efficient pulse coupled oscillator (EEPCO) has been proposed, which employs the self-organizing method by combining biologically and non-biologically inspired network systems and has proven to reduce the transmission delay and energy consumption of sensor nodes. However, the EEPCO method has only been experimented in attack-free networks without
... Show MoreThree Schiff bases from Benzaldehyde and Salicylaldehyde have been synthesized (A, 1and 2) and two of them (1and 2) have been tested for anti-inflammatory activity. The p-aminobenzene sulfonamide has been synthesized from acetanilide through the addition of excess chlorosulfonic acid then concentrated ammonia solution; Schiff base of this derivative (2) exhibited good level of activity against egg-white induced edema in rat hind paw, while the other tested derivative exhibited no activity.
Key words: Schiff bases, sulfonamide derivatives, salicylaldehyde
Aims: To assess the success rate and implant stability changes of narrow dental implants (NDIs) during the osseous healing period. Materials and methods: This prospective observational clinical study included 21 patients with narrow alveolar ridge of restricted mesiodistal interdental span who received NDIs. The alveolar ridge width was determined by the ridge mapping technique. Implant stability was measured using Periotest® M immediately after implant insertion then after 4 weeks, 8 weeks and 12 weeks postoperatively. The outcome variables were success rate and implant stability changes during the healing period. The statistical analysis included one-way analysis of variance (ANOVA) and Tukey\'s multiple comparisons test, values < 0.05 w
... Show MoreA high settlement may take place in shallow footing when resting on liquefiable soil if subjected to earthquake loading. In this study, a series of shaking table tests were carried out for shallow footing resting on sand soil. The input motion is three earthquake loadings (0.05g, 0.1g, and 0.2g). The study includes a reviewing of theoretical equations (available in literatures), which estimating settlement of footings due to earthquake loading, calibration, and verification of these equations with data from the shaking table test for improved soil by grouting and unimproved soil. It is worthy to note that the grouting materials considered in this study are the Bentonite and CKD slurries. A modification to the seismic set
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