Preferred Language
Articles
/
OUKk-pkBMeyNPGM307tG
Titanium Dioxide for Improved Performance of Reclaimed Asphalt Pavement Aggregates in Concrete
...Show More Authors

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.

Scopus Clarivate Crossref
View Publication
Publication Date
Sat Jul 28 2018
Journal Name
Journal Of Engineering
Effectiveness of Meso-Scale Approach in Modeling of Plain Concrete Beam
...Show More Authors

The main aim of this research paper is investigating the effectiveness and validity of Meso-Scale Approach (MSA) as a modern technique for the modeling of plain concrete beams. Simply supported plain concrete beam was subjected to two-point loading to detect the response in flexural. Experimentally, a concrete mix was designed and prepared to produce three similar standard concrete prisms for flexural testing. The coarse aggregate used in this mix was crushed aggregate. Numerical Finite Element Analysis (FEA) was conducted on the same concrete beam using the meso-scale modeling. The numerical model was constructed to be a bi-phasic material consisting of cement mortar and coarse aggregate. The interface between the two c

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Oct 02 2023
Journal Name
Journal Of Polymer Research
Morphological study of porous aromatic schiff bases as a highly effective carbon dioxide storages
...Show More Authors

Carbon dioxide (CO2) capture and storage is a critical issue for mitigating climate change. Porous aromatic Schiff base complexes have emerged as a promising class of materials for CO2 capture due to their high surface area, porosity, and stability. In this study, we investigate the potential of Schiff base complexes as an effective media for CO2 storage. We review the synthesis and characterization of porous aromatic Schiff bases materials complexes and examine their CO2 sorption properties. We find that Schiff base complexes exhibit high CO2 adsorption capacity and selectivity, making them a promising candidate for use in carbon capture applications. Moreover, we investigate the effect of various parameters such as temperature, and pressu

... Show More
Publication Date
Mon Nov 01 2021
Journal Name
Journal Of Engineering
Effect of Fly Ash on Some Properties of Reactive Powder Concrete
...Show More Authors

To achieve sustainability in the field of civil engineering, there has become a great interest in developing reactive powder concrete RPC through the use of environmentally friendly materials to reduce the release of CO2 gas produced from cement factories as well as contribute to the recycling of industrial wastes that have a great impact on environmental pollution.

In this study, reactive powder concrete was prepared using total binder content of 800 kg/m3, water to binder ratio (0.275), and micro steel fibers  1% by volume of concrete. The experimental program included replacing fly ash with (8, 12, 16) % by cement weight to find the optimal ratio, which achieved the best mechanical proper

... Show More
View Publication Preview PDF
Crossref (17)
Crossref
Publication Date
Thu Jul 01 2021
Journal Name
European Journal Of Dentistry
Effects of Long Durations of RF–Magnetron Sputtering Deposition of Hydroxyapatite on Titanium Dental Implants
...Show More Authors

Objectives Dental implant is a revolution in dentistry; some shortages are still a focus of research. This study use long duration of radiofrequency (RF)–magnetron sputtering to coat titanium (Ti) implant with hydroxyapatite (HA) to obtain a uniform, strongly adhered in a few micrometers in thickness. Materials and Methods Two types of substrates, discs and root form cylinders were prepared using a grade 1 commercially pure (CP) Ti rod. A RF–magnetron sputtering device was used to coat specimens with HA. Magnetron sputtering was set at 150 W for 22 hours at 100°C under continuous argon gas flow and substrate rotation at 10 rpm. Coat properties were evaluated via field emission scanning electron microscopy (FESEM), scanning electro

... Show More
View Publication Preview PDF
Scopus (17)
Crossref (15)
Scopus Crossref
Publication Date
Thu Jun 30 2022
Journal Name
Iraqi Journal Of Laser
PDF Fiber Laser Effect on Bond Strength of Titanium implant abutment to Resin Cement
...Show More Authors

Aim: surface modification of titanium using fiber laser 1064 nm to enhance the bond strength to resin cement. Material and Methods: thirty titanium discs of 0.6 cm x 0.3 cm (diameter and thickness respectively) were categorized after preparation into three groups (n=10) as follows: control group with no surface treatment and two test groups were treated with fiber laser after estimation the appropriate parameters in the pilot study which are 81 ns pulse duration, 30,000 Hz frequency, 50 µm spot size and 10,000 mm/s scanning speed and different average power values (10 W and 20 W) depending on the tested group. Titanium discs surface characterization was performed by scanning electron microscope (SEM), a

... Show More
View Publication Preview PDF
Publication Date
Tue May 01 2018
Journal Name
Journal Of Engineering
Evaluation of Job-Mix Formula Tolerances as Related to Asphalt Mixtures Properties
...Show More Authors

The current Iraqi standard specifications for roads and bridges allowed the prepared Job-Mix Formula for asphalt mixtures to witness some tolerances with regard to the following: coarse aggregate gradation by ± 6.0 %, fine aggregate gradation by ± 4.0 %, filler gradation by ± 2.0 %, asphalt cement content by ± 0.3 % and mixing temperature by ± 15 oC. The objective of this work is to evaluate the behavior of asphalt mixtures prepared by different aggregates gradations (12.5 mm nominal maximum size) that fabricated by several asphalt contents (40-50 grade) and various mixing temperature. All the tolerances specified in the specifications are taken into account, furthermore, the zones beyond these tolerances

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Aug 01 2022
Journal Name
Engineering, Technology & Applied Science Research
Castellated Beams with Fiber-Reinforced Lightweight Concrete Deck Slab as a Modified Choice for Composite Steel-Concrete Beams Affected by Harmonic Load
...Show More Authors

The behavior investigation of castellated beams with fiber-reinforced lightweight concrete deck slab as a modified choice for composite steel-concrete beams affected by harmonic load is presented in this study. The experimental program involved six fixed-supported castellated beams of 2140mm size. Three types of concrete were included: Normal Weight Concrete (NWC), Lightweight Aggregate Concrete (LWAC), and Lightweight Fiber-Reinforced Aggregate Concrete (LWACF). The specimens were divided into two groups: the first comprised three specimens tested under harmonic load effect of 30Hz operation frequency for 3 days, then the residual strength was determined through static load application. The second group included three specimens ide

... Show More
Crossref (12)
Crossref
Publication Date
Sat Jun 01 2024
Journal Name
Iraqi Journal Of Physics
A Study the Addition of Silver Dioxide on Some Optical Properties of Phosphate Bioactive Glass
...Show More Authors

This study investigates the influence of silver oxide (Ag2O) concentration on the optical characteristics of phosphate bioactive glasses (PBGs). PBGs have emerged as promising alternatives to conventional silicate glasses in the medical field due to their excellent bioactivity and chemical resistance. Samples with varying Ag2O concentrations (0, 0.25, 0.5, and 0.75g) were sintered at 780°C for 2 hrs in an electric furnace. The samples were subjected to Fourier transfer infrared spectroscopy (FTIR), ultraviolet-visible (UV-Vis) spectroscopy, and photoluminescence (PL) tests to assess their functional groups and optical properties. By analyzing the FTIR spectrum of phosphate bioactive glass containing different amounts of Ag2O, it is

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Oct 31 2013
Journal Name
Al-khwarizmi Engineering Journal
Influence of the Applied Potential and Temperature on the Electrode position of the Lead Dioxide
...Show More Authors

The excellent specifications of electrodes coated with lead dioxide material make it of great importance in the industry. So it was suggested this study, which includes electrodeposition of lead dioxide on graphite substrate, knowing that the electrodeposition of lead dioxide on graphite studied earlier in different ways.

In this work the deposition process for lead dioxide conducted using electrolytic solution containing lead nitrate concentration 0.72 M with the addition of some other material to the solution, such as copper nitrate, nickel nitrate, sodium fluoride and cetyl trimethyl ammonium bromide, but only in very small concentrations. As for the operating conditions, the effect of change potential and temperature as well

... Show More
View Publication Preview PDF
Publication Date
Sat Jun 06 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Pores in Dual Nano Hydroxyapatite Coating on Thermally Oxidized Commercial Pure Titanium: Mechanical and Histological Evaluation
...Show More Authors

Background:In this study,TiO2 layer was thermally grown as a diffusion barrier on CP Ti substrate prior to electrophoretic deposition of HA coatings, to improve the coating’s compatibility also macro and micro pores in nano Hydroxyapatite dual coatings were created and their effect on the bond strength between the bone and implant was evaluated. Materials and methods: Electrophoretic Deposition technique (EPD) was used to obtain coatings for each one of four types of Hydroxyapatite(HA)on CP Ti screws (micro HA, nano HA, dual nano HA with micro pores, dual nano HA with macro pores) where carbon particles used as fugitive material to be removed by thermal treatment to create porosity.For examination of the changes occurred on the subs

... Show More
View Publication Preview PDF
Crossref (2)
Crossref