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Titanium Dioxide for Improved Performance of Reclaimed Asphalt Pavement Aggregates in Concrete
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This work presents an innovative approach to enhancing the performance of concrete with reclaimed asphalt pavement (RAP) aggregates using titanium dioxide (TiO2) nanoparticles. Traditional limestone coarse aggregates were partially replaced with 30% and 50% RAP aggregates; a subset of mixtures containing RAP aggregates was treated with TiO2 nanoparticles. The rheological, mechanical, and long-term properties of concrete, along with changes in its chemical composition following the addition of RAP and TiO2, were evaluated. Results revealed that using 30% and 50% RAP in concrete mixtures reduced their compressive strength by 18% and 27%, respectively. However, using TiO2 in those mixtures enhanced their compressive strength by 8.7% and 6.3%. Moreover, concrete with 50% RAP exhibited an 85% increase in water absorption (the highest among all mixtures) compared to the control. TiO2 treatment was most beneficial in the 30% RAP mixture, reducing its water absorption by 32.5% compared to its untreated counterpart. Additionally, the 30% RAP mixture treated with TiO2 showed the highest resistance to sulfates among modified mixtures, as its compressive strength decreased by 10.4% compared to a decrease of 23% in the strength of the untreated 30% RAP mixture. Statistical analysis using single-factor ANOVA showed that integrating RAP aggregates with or without the presence of TiO2 particles would significantly affect the concrete properties in terms of their population means. The t-test analysis, on the other hand, proved sufficient evidence that the mean values of the 30% RAP mixture treated with TiO2 would not differ significantly from the control in terms of its slump and water absorption properties. The chemical structure analysis revealed an increase in the Si-O-Si and Si-O functional groups when using TiO2 in RAP mixtures, suggesting improved hydration activity and accelerated C-S-H formation in the treated RAP mixtures. Moreover, distinct C-H peaks were witnessed in concrete with untreated RAP aggregates, resulting from the aged asphalt coating on the RAP, which weakened the bond between the RAP and the cementitious matrix.

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Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Engineering
Impact of Preparing HMA with Modified Asphalt Cement on Moisture and Temperature Susceptibility
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Many researchers tried to prevent or reduce moisture damage and its sensitivity to temperature to improving the performance of hot mix asphalt because it is decreasing the functional and structural life of fixable pavement due to the moisture damage had exposed to it.

The main objective of this study is to inspect the effect of (fly ash “3%, 6%, 12%”, hydrated lime”5%, 10%, 20%” and silica fumes”1%, 2%, 4%) referring to previous research by the net weight asphalt cement as a modified material on the moisture and temperature sensitivity of hot mix asphalt. This was done using asphalt from AL-Nasiria refinery with penetration grade 40-50, nominal maximum size (12.5) mm (surface course) of aggregate and on

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Publication Date
Tue Dec 27 2022
Journal Name
Journal Of Lasers In Medical Sciences
Influence of Fiber Laser (1064 nm) on Shear Bond Strength of Titanium Abutment and Resin Cement
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Introduction: The present study was performed to evaluate the influence of a 1064 nm fiber laser on shear bond strength (SBS) at the interface of titanium and resin cement. Methods: Forty titanium discs of 6 mm × 3 mm (diameter and thickness respectively) were categorized into four groups (n=10): control group without any surface treatment and three groups treated with a fiber laser with 81 ns pulse duration, 30 kHz frequency, 10000 mm/s scanning speed, 0.05 mm spot size, and different average power values (3, 5 and 7 W) depending on the tested group. Titanium disc characterization was performed by the scanning electron microscope (SEM) and surface roughness tester. Phase analysis was achieved using an X-ray diffractometer (XRD). F

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Publication Date
Wed Jan 04 2017
Journal Name
Applied Research Journal
ASSESSMENT OF SHEAR AND COMPRESSIBILITY PROPERTIES OF ASPHALT STABILIZED COLLAPSIBLE SOIL
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One of the major problems facing the road construction engineer is the collapsible granular soil which may be used for embankment construction. Problems appears when such compacted soil come in touch with water, it exhibits cracking and uncontrolled settlement. Collapsible soils are defined as any unsaturated soil that goes through a radical rearrangement of practice and great loss of volume upon wetting, with or without additional loading. An attempt has been made in this investigation to stabilize the collapsible soil of Nasiriya with asphalt emulsion. Specimens of pure and asphalt emulsion stabilized soil have been prepared using optimum fluid content and tested. The first group of specimens of (60x60x20) cm have been tested for direct s

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Publication Date
Tue Jun 01 2021
Journal Name
Civil Engineering Journal
Effect of Polypropylene Fibers on moisture Susceptibility of Warm Mix Asphalt
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Warm Mix Asphalt (WMA) is a modern energy-saving process that uses environmentally friendly materials, has lower mixing and compaction temperatures, and uses less energy and releases less contaminants than conventional hot mix asphalt. Moisture damage poses one of the main challenges of the material design in asphalt pavements. During its design life, the asphalt pavement is exposed to the effect of moisture from the surrounding environment. This research intends to investigate the role of the polypropylene fibres for modifying the moisture susceptibility for the WMA by using different percentages of polypropylene (namely 2, 4, and 6%) by weight of the binder of the control mixture (WMA). In this paper, the physical characteristics

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Publication Date
Thu Nov 01 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Nurses Performance in Pain Management for Burn Patient at Baghdad City’s General Hospitals
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Abstract A descriptive study was carried out on nurses who were working at burn. Units in Baghdad city hospitals, Al-Kindy , Al-Yarmook, Al-Qadisiya, Al-karkh, and Al-Karama hospital, in the period from 20th july 2003 to 20th November 2003. The study aimed to identify the nurses performance about pain management for burned patients at burn units and find out the relationship between the demographic characteristics and performance . A purposive (non-probability) sample of (40) nurses, (24) male nurses and (16) female. The data were collected through the use of observational checklist, which comprised (

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Suggestive Framework for Applying Performance and Programs Budget in Iraqi Government Units Environment
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Abstract

This research  aims to reform the Iraqi public budget through going into the challenges the budget faces in applying item-line budget in its preparation, implementation and control; which encourage extravagance and waste instead of rationalizing expenditures. This  is shown in the data analysis of Federal public budget laws in Iraq for the years from 2005 till 2013; there was a continuous increase in the aggregate public expenditures in the public budget for the years previously mentioned, as the public expenditures growth has reached into the percent 284.71% in 2013. In addition the public budget for these years (2005-2013) is being prepared with planned deficit without confirming that

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Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
High performance liquid chromatographic method for the determination of guaifenesin in pharmaceutical syrups and in environmental samples
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A simple, precise, rapid, and accurate reversed – phase high performance liquid chromatographic method has been developed for the determination of guaifenesin in pure from pharmaceutical formulations.andindustrial effluent. Chromatography was carried out on supelco L7 reversed- phase column (25cm × 4.6mm), 5 microns, using a mixture of methanol –acetonitrile-water: (80: 10 :10 v/v/v) as a mobile phase at a flow rate of 1.0 ml.min-1. Detection was performed at 254nm at ambient temperature. The retention time for guaifenesin was found 2.4 minutes. The calibration curve was linear (r= 0.9998) over a concentration range from 0.08 to 0.8mg/ml. Limit of detection (LOD) and limit of quantification ( LOQ) were found 6µg/ml and 18µg/ml res

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Publication Date
Fri Dec 01 2017
Journal Name
International Journal Of Electrical And Computer Engineering (ijece)
Performance Evaluation of UDP, DCCP, SCTP and TFRC for Different Traffic Flow in Wired Networks
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<p>The demand for internet applications has increased rapidly.  Providing quality of service (QoS) requirements for varied internet application is a challenging task. One important factor that is significantly affected on the QoS service is the transport layer. The transport layer provides end-to-end data transmission across a network. Currently, the most common transport protocols used by internet application are TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). Also, there are recent transport protocols such as DCCP (data congestion control protocol), SCTP (stream congestion transmission protocol), and TFRC (TCP-friendly rate control), which are in the standardization process of Internet Engineering Task

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Publication Date
Tue Jun 01 2021
Journal Name
Al-khwarizmi Engineering Journal
Modeling and Simulation for Performance Evaluation of Optical Quantum Channels in Quantum key Distribution Systems
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In this research work, a simulator with time-domain visualizers and configurable parameters using a continuous time simulation approach with Matlab R2019a is presented for modeling and investigating the performance of optical fiber and free-space quantum channels as a part of a generic quantum key distribution system simulator. The modeled optical fiber quantum channel is characterized with a maximum allowable distance of 150 km with 0.2 dB/km at =1550nm. While, at =900nm and =830nm the attenuation values are 2 dB/km and 3 dB/km respectively. The modeled free space quantum channel is characterized at 0.1 dB/km at =860 nm with maximum allowable distance of 150 km also. The simulator was investigated in terms of the execution of the BB84 p

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Publication Date
Tue Jun 01 2021
Journal Name
Al-khwarizmi Engineering Journal
Modeling and Simulation for Performance Evaluation of Optical Quantum Channels in Quantum key Distribution Systems
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In this research work, a simulator with time-domain visualizers and configurable parameters using a continuous time simulation approach with Matlab R2019a is presented for modeling and investigating the performance of optical fiber and free-space quantum channels as a part of a generic quantum key distribution system simulator. The modeled optical fiber quantum channel is characterized with a maximum allowable distance of 150 km with 0.2 dB/km at =1550nm. While, at =900nm and =830nm the attenuation values are 2 dB/km and 3 dB/km respectively. The modeled free space quantum channel is characterized at 0.1 dB/km at =860 nm with maximum allowable distance of 150 km also. The simulator was investigated in terms of the execution of the BB84 prot

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Scopus (5)
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