Preferred Language
Articles
/
ijp-652
Optical and A.C. Electrical Properties for Polypyrrole and Polypyrrole/Graphene (ppy/gn) Nanocomposites
...Show More Authors

In this work, chemical oxidation was used to polymerize conjugated polymer "Polypyrrole" at room temperature Graphene nanoparticles were added by in situ-polymerization to get (PPY-GN) nano. Optical and Electrical properties were studied for the nanocomposites. optical properties of the nanocomposites were studied by UV-Vis spectroscopy at wavelength range (200 -800 nm). The result showed optical absorption spectra were normally determined and the result showed that the maximum absorbance wave length at 280nm and 590nm. The optical energy gap has been evaluated by direct transition and the value has decreased from (2.1 eV for pure PPy) to (1.3 eV for 5 %wt. of GN). The optical constants such as the band tail width ΔE was evaluated, the value of ΔE for pure PPy was (0.0949eV) while for 5 wt. % of GN it was (0.5156 eV), It has been observed that the Urbach tail for pure PPy was smaller than that for PPy/GN nanocomposites and it increase as GN concentration increases. The A.C electrical conductivity at range of frequency (103Hz-106Hz) was increased by increasing the frequency and GN concentration about four order of magnitude. The s value was about (0.653-0.962) which means that the mechanism of conductivity is correlated hopping mechanism (C. H. P.). The dielectric constant and dielectric lose were determined and found to decrease with increasing frequency.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon May 02 2022
Journal Name
Neuroquantology
Manufacturing and Improving Engineering Properties of Silica Bricks from Raw Materials
...Show More Authors

Refractories are mineral and chemical-, based, materials with excellent heat resistance, making them ideal for use in the construction of ovens, furnace walls industries. According to this our research is concerned to study the effect of addition of (4% CaO) and (5% graphite) on the silica brick properties. Different amounts of CaO and Graphite were included in the white sand (raw ingredients) of silica bricks as a binder to prepare the composition then the composition were sintered using Different sintering temperatures ranging from (1000–1400)𝛐C under static air. Density, thermal conductivity, porosity, and water absorption Compression there was power tested after sintering. XRD analysis was used to identify raw materials’

... Show More
View Publication
Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Thin Solid Films
Physico-chemical properties of CrMoN coatings - combined experimental and computational studies
...Show More Authors

In this study, Cr−Mo−N thin films with different Mo contents were synthesised via closed field unbalanced magnetron sputtering ion plating. The effects of Mo content on the microstructure, chemical bonding state, and optical properties of the prepared films were investigated by X-ray diffraction spectroscopy (XRD), X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy, and ultraviolet-visible spectrophotometry. XRD results determined the face centered cubic (fcc) structure of pure CrN film. The incorporation of molybdenum (Mo) in the CrN matrix was confirmed by both XRD and XPS analyses. The CrMoN coatings demonstrate various polycrystalline phases including CrN, γ-Mo2N, Cr with oxides layers of MoO3, CrO3

... Show More
View Publication
Scopus (22)
Crossref (18)
Scopus Clarivate Crossref
Publication Date
Fri Oct 25 2024
Journal Name
Infrastructures
Physical, Mechanical and Durability Properties of Eco-Friendly Engineered Geopolymer Composites
...Show More Authors

Engineered geopolymer composite (EGC) is a high-performance material with enhanced mechanical and durability capabilities. Ground granulated blast furnace slag (GGBFS) and silica fume (SF) are common binder materials in producing EGC. However, due to the scarcity and high cost of these materials in some countries, sustainable alternatives are needed. This research focused on producing eco-friendly EGC made of cheaper and more common pozzolanic waste materials that are rich in aluminum and silicon. Rice husk ash (RHA), granite waste powder (GWP), and volcanic pumice powder (VPP) were used as partial substitutions (10–50%) of GGBFS in EGC. The effects of these wastes on workability, unit weight, compressive strength, tensile strengt

... Show More
View Publication
Scopus (39)
Crossref (41)
Scopus Clarivate Crossref
Publication Date
Mon Aug 01 2022
Journal Name
Baghdad Science Journal
Recycling of Chicken Egg Shells into Nanopowder: Synthesis, and its Properties
...Show More Authors

Increase in unconventional resources of calcium (Ca+2) for fowls, aquaculture and native animals was improved. This work was planned to define the most polymorph of calcium carbonate (CaCO3) that take place in the two types of chicken eggshells (local and imported type). In this research, the comparative analysis of calcium carbonate (CaCO3) content was approved for nominated eggshells of native strain and imported chicken via Field Emission Scanning Electron Microscope (FESEM), Transmission Electron Microscope (TEM), Fourier-Transform Infrared Spectroscopy (FTIR) and Powder X-Ray Diffraction (PXRD) analysis. The results demonstrate that native and imported chicken eggshells comprise calcite morph that ha

... Show More
View Publication Preview PDF
Scopus (2)
Crossref (5)
Scopus Clarivate Crossref
Publication Date
Fri May 01 2020
Journal Name
Applied Thermal Engineering
Thermal performance of a flat-plate solar collector using aqueous colloidal dispersions of graphene nanoplatelets with different specific surface areas
...Show More Authors

The effects of using aqueous nanofluids containing covalently functionalized graphene nanoplatelets with triethanolamine (TEA-GNPs) as novel working fluids on the thermal performance of a flat-plate solar collector (FPSC) have been investigated. Water-based nanofluids with weight concentrations of 0.025%, 0.05%, 0.075%, and 0.1% of TEA-GNPs with specific surface areas of 300, 500, and 750 m2/g were prepared. An experimental setup was designed and built and a simulation program using MATLAB was developed. Experimental tests were performed using inlet fluid temperatures of 30, 40, and 50 °C; flow rates of 0.6, 1.0, and 1.4 kg/min; and heat flux intensities of 600, 800, and 1000 W/m2. The FPSC’s efficiency increased as the flow rate and hea

... Show More
Crossref (43)
Crossref
Publication Date
Thu Sep 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
The Role of Continuous Improvement Strategy (Kaizen) in organizational innovation: An analytical research in the General Company of Electrical and Electronic Industries /The Ministry of Industry and Minerals
...Show More Authors

This paper aims at the fact that most organizations today suffer from a waste of time, effort, and cost, and they have difficulty in achieving the best performance situations and compete strongly. The researcher distributed 108 questionnaires as a statistical analyzable sample society where the sample intentionally consists of general managers, department head, and division head. The questionnaire was formulated according to the Likert scale. The use of personal interviews and observations are additional tools for data collection and a number of statistical methods is used for data analysis such as simple regression and correlation coefficient (Pearson). One of the most prominent conclusions is that the company has adequate and c

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Fri Mar 01 2013
Journal Name
Indian Journal Of Applied Research
Optical study of effect of thiourea on CdS thin films
...Show More Authors

Abstract: This paper presents the results of the structural and optical analysis of CdS thin films prepared by Spray of Pyrolysis (SP) technique. The deposited CdS films were characterized using spectrophotometer and the effect of Sulfide on the structural properties of the films was investigated through the analysis of X-ray diffraction pattern (XRD). The growth of crystal became stronger and more oriented as seen in the X-ray diffraction pattern. The studying of X-ray diffraction showed that; all the films have the hexagonal structure with lattice constants a=b=4.1358 and c=6.7156A°, the crystallite size of the CdS thin films increases and strain (ε) as well as the dislocation density (δ) decreases. Also, the optical properties of the

... Show More
Preview PDF
Publication Date
Tue Feb 01 2022
Journal Name
Case Studies In Thermal Engineering
Robust composite temperature control of electrical tube furnaces by using disturbance observer
...Show More Authors

As one type of resistance furnace, the electrical tube furnace (ETF) typically experiences input noise, measurement noise, system uncertainties, unmodeled dynamics and external disturbances, which significantly degrade its temperature control performance. To provide precise, and robust temperature tracking performance for the ETF, a robust composite control (RCC) method is proposed in this paper. The overall RCC method consists of four elements: First, the mathematical model of the ETF system is deduced, then a state feedback control (SFC) is constructed. Third, a novel disturbance observer (DO) is designed to estimate the lumped disturbance with one observer parameter. Moreover, the stability of the closed loop system including controller

... Show More
View Publication
Scopus (18)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Sun Jun 12 2011
Journal Name
Baghdad Science Journal
The parameters effect on the holographic optical elements
...Show More Authors

In this work we fabrication holographic optical element diffraction grating thickness 40?m and mirror90?m by using dichromated gelatin,to perform that we have to use the Nd-yaG laser doubling frequency of wavelenght (532)nm and its powers of (80)mWatt.we have studyed the thickness and concentration dichromat effect in mirror reflaction ,effect of angle of reconstruction beam in band width and diffraction efficiency ,study effect gelatin hardener of the diffraction efficiency.

View Publication Preview PDF
Crossref
Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
optical proprties of poly crystaline CdS thin films
...Show More Authors

Studied the optical properties of the membranes CdS thin containing different ratios of ions cadmium to sulfur attended models manner spraying chemical gases on the rules of the glass temperature preparation (350c) were calculated energy gap allowed direct these membranes as observed decrease in the value of the energy gap at reducing the proportion ofsulfur ions as absorption coefficient was calculated

View Publication Preview PDF