Preferred Language
Articles
/
VhgUTJQBVTCNdQwC5ASt
Improving the Dielectric, Thermal, and Electrical Properties of Poly (Methyl Methacrylate)/Hydroxyapatite Blends by Incorporating Graphene Nanoplatelets
...Show More Authors

In this article, the casting method was used to prepare poly(methyl methacrylate)/hydroxyapatite (PMMA/HA) nanocomposite films incorporated with different contents (0.5, 1, and 1.5 wt%) of graphene nanoplatelets (Gnp). The chemical properties and surface morphology of the PMMA/HA blend and PMMA/HA/Gnp nanocomposite were characterized using FTIR, and SEM analysis. Besides, the thermal conductivity, dielectric and electrical properties at (1–107 Hz) of the PMMA/HA blend and PMMA/HA/Gnp composites were investigated. The structural analysis showed that the synthesized composites had a low agglomerated state, with multiple wrinkles of graphene flakes in the PMMA/HA blend. The thermal conductivity was improved by more than 35-fold its value for pure PMMA. The AC and DC electrical conductivities of PMMA/HA/Gnp composites were enhanced with increasing the amount of Gnp and the estimated exponent (s) being between 1.25 and 1.3. The values of the real part (ɛ′) and imaginary part (ε′′) of the dielectric constant as well as electrical impedance depend on the Gnp ratio. The value of ɛ′ was reduced at the lower frequency (< 105 Hz) and became constant at the higher frequency which attributed to the relaxation time. The values of ε″ are small at low frequencies and increase with increased frequency due to the electronic polarization effects as well as to the dipoles not beginning to follow the field variation at higher frequencies. The increase in the dielectric loss, tan(δ), with an increase in Gnp content, to 0.5 wt%, due to the interfacial polarization mechanism occurred in the composite’s films corresponding to frequencies

Scopus Clarivate Crossref
View Publication
Publication Date
Wed Jan 02 2019
Journal Name
Pramana
The description of quantum dielectric function for insulators over Bethe surface
...Show More Authors

View Publication
Scopus (4)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Sun Dec 01 2024
Journal Name
Iraqi Journal Of Physics
Study of the Sensitivity of Carbon Quantum Dots for NO2 Gas Sensor and improve it using Graphene
...Show More Authors

Gas sensors are essential for detecting noxious gases that have a detrimental effect on people's health and welfare. Carbon quantum dots (CQDs) are the fundamental component of gas detectors. CQDs and graphene (Gr) were prepared using the electrochemical method. The gas sensitivity of these materials was evaluated at different temperatures (150, 200, 250 °C) to assess their effectiveness. Subsequently, experiments were conducted at different temperatures to ascertain that the combination of CQDs and Gr, with various percentages of Gr and CQDs, exhibited superior gas sensitization properties compared to CQDs alone. This was evaluated based on criteria such as sensitivity, recovery time, and reaction time. Interestingly, the combination was

... Show More
View Publication
Crossref (2)
Crossref
Publication Date
Wed Apr 07 2021
Journal Name
Egyptian Journal Of Chemistry
Copolymers of Castor and Corn Oils with Lauryl Methacrylate as Green Lubricating Additives
...Show More Authors

During 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 More
View Publication Preview PDF
Scopus (11)
Scopus Clarivate Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Energy Procedia
Enhanced efficiency of CdTe Photovoltaic by thermal evaporation Vacuum
...Show More Authors

Crossref (22)
Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Energy Procedia
Enhanced efficiency of CdTe Photovoltaic by thermal evaporation Vacuum
...Show More Authors

View Publication
Scopus (27)
Crossref (22)
Scopus Clarivate Crossref
Publication Date
Mon Feb 01 2021
Journal Name
Journal Of Physics: Conference Series
The Fear Effect on a Food Chain Prey-Predator Model Incorporating a Prey Refuge and Harvesting
...Show More Authors
Abstract<p>In this paper, we investigate the impact of fear on a food chain mathematical model with prey refuge and harvesting. The prey species reproduces by to the law of logistic growth. The model is adapted from version of the Holling type-II prey-first predator and Lotka-Volterra for first predator-second predator model. The conditions, have been examined that assurance the existence of equilibrium points. Uniqueness and boundedness of the solution of the system have been achieve. The local and global dynamical behaviors are discussed and analyzed. In the end, numerical simulations are confirmed the theoretical results that obtained and to display the effectiveness of varying each parameter</p> ... Show More
View Publication
Scopus (17)
Crossref (11)
Scopus Crossref
Publication Date
Thu Mar 12 2020
Journal Name
Al-khwarizmi Engineering Journal
Improving Reverse Engineering Processes by using Articulated Arm Coordinate Measuring Machine
...Show More Authors

The invention relates to a coordinate measuring machine (CMM) for determining a measuring position of a probe. The AACMM isdepends on the robotkinematics (forward and reverse) in their measurementprinciple, i.e., using the AACMM links and joint angles todetermine the exact workspace or part coordinates. Hence, themeasurements are obtained using an AACMM will be extremely accurate and precise since that ismerely dependent on rigid structural parameters and the only source of measurement error is due to human operators. In this paper, a new AACMM design was proposed. The new AACMM design addresses common issues such as solving the complex kinematics, overcoming the workspace limitation, avoiding singularity, and eliminating the effects of

... Show More
View Publication Preview PDF
Publication Date
Wed Mar 01 2023
Journal Name
Iraqi Journal Of Physics
Bandwidth Improvement of a Cone-Inverted Cylindrical and Cross Hybrids Dielectric Resonator Antennas
...Show More Authors

In this work, two cone-inverted cylindrical and cross-hybrid dielectric resonator antennas are stacked and excited by the coaxial probe method with an operating standard resonant frequency of 5.438 GHz. A drawback of these standard Dielectric Resonator Antennas (DRAs) is their narrow bandwidth. For good antenna performance, a stacked DR geometry and a thick dielectric substrate having a low dielectric constant are desired since this provides large bandwidth, better radiation power, reduces conductor loss and nonappearance of surface waves. Many approaches, such as changing the shape of the dielectric resonator, have been used to enhance bandwidth. Using DRA, having the lowest dielectric constant, increases the bandwidth and the electroma

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Oct 01 2010
Journal Name
Iraqi Journal Of Physics
The effect of TiO2 addition on the thermal conductivity of Polymethylmetha acrylate, Polycarbonate and Polystyrene Polymers
...Show More Authors

Thermal conductivity measurement was done for specimens of Polystyrene/ titanium dioxide, Polycarbonate/ titanium dioxide and Polymethylmetha acrylate/ titanium dioxide composites for weight ratio of 1.9/ 0.1 and 1.8/ 0.2 wt% for different thickness of the samples. The experimental results show that the thermal conductivity is increased with the increasing of thickness of layers and with the weight ratio of TiO2

View Publication Preview PDF
Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Engineering
Removal of Methyl Orange from Aqueous Solutions by Adsorption Using Corn Leaves as Adsorbent Material
...Show More Authors

A comparative study was done on the adsorption of methyl orange dye (MO) using non-activated and activated corn leaves with hydrochloric acid as an adsorbent material. Scanning electron microscopy (SEM) and Fourier Transform Infrared spectroscopy (FTIR) were utilized to specify the properties of adsorbent material. The effect of several variables (pH, initial dye concentration, temperature, amount of adsorbent and contact time) on the removal efficiency was studied and the results indicated that the adsorption efficiency increases with the increase in the concentration of dye, adsorbent dosage and contact time, while inversely proportional to the increase in pH and temperature for both the treated and untreated corn leav

... Show More
View Publication Preview PDF
Crossref (25)
Crossref