Preferred Language
Articles
/
bsj-7904
Study the Structural Properties of Porous Silicon and their Applications as Thermal Sensors
...Show More Authors

The photo-electrochemical etching (PECE) method has been utilized to create pSi samples on n-type silicon wafers (Si). Using the etching time 12 and 22 min while maintaining the other parameters 10 mA/cm2 current density and HF acid at 75% concentration.. The capacitance and resistance variation were studied as the temperature increased and decreased for prepared samples at frequencies 10 and 20 kHz. Using scanning electron microscopy (SEM), the bore width, depth, and porosity % were validated. The formation of porous silicon was confirmed by x-ray diffraction (XRD) patterns, the crystal size was decreased, and photoluminescence (PL) spectra revealed that the emission peaks were centered at 2q of 28.5619° and 28.7644° for etching time 12 and 22 min, respectively. Studying the capacitance and resistivity during temperature increasing and decreasing for both itching times shows clearly that the prepared pSi as a thermal sensor is working better and in more selectivity for 20 min itching time

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Dec 01 2010
Journal Name
Al-khwarizmi Engineering Journal
Evaluation of Mechanical Properties of Particulate Composites
...Show More Authors

A series of experiments have been taken out to test the validity of the effect of Aluminum hydrate on its interaction with Aluminum during sintering of aluminum metal matrix. The approach has been shown to be valid and several compositions have been fabricated. The alumina hydrate particle size and the amount of alumina hydrate in the composites are also shown to have an influence on the extent of densification.

The densities for all sintered specimens were measured. It was found that density increases as compaction pressure increases, the density decreases as particles size increases. At 400 MPa there is an optimum particles size which is (90-125) µm to reach maximum density and the density decreases as volume fraction increase

... Show More
View Publication Preview PDF
Publication Date
Thu May 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Effect of Journal Misalignment on the Static Characteristics of Porous Journal Bearings Lubricated with Couple Stress Fluid
...Show More Authors

In this paper, a theoretical study to the effect of journal misalignment on the static characteristics of oil filled porous journal bearing when lubricated with couple stress fluid has been carried out.

The analytical model used through this work is for a bearing with isotropic permeability. Considering isotropic permeability the Reynolds' equation for the oil film is modified to include a so – called filter term and the effect of fluid coupled stress. The pressure equation for the porous medium is obtained from Darcy's law and continuity equation. The equation which was used to evaluate the oil film thickness was modified to include the effect of possible misalignment in longitudinal and transverse directions. The governing eq

... Show More
View Publication Preview PDF
Publication Date
Mon Dec 20 2021
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
STUDY THE PHYSICAL AND CHEMICAL PROPERTIES AND DETERMINATION THE CYTOTOXICITY OF KOJIC ACID PRODUCED FROM THE LOCAL ISOLATE ASPERGILLUS FLAVUS WJF81 AND THEIR EFFECTS ON CONSUMER HEALTH.: STUDY THE PHYSICAL AND CHEMICAL PROPERTIES AND DETERMINATION THE CYTOTOXICITY OF KOJIC ACID PRODUCED FROM THE LOCAL ISOLATE ASPERGILLUS FLAVUS WJF81 AND THEIR EFFECTS ON CONSUMER HEALTH.
...Show More Authors

Steps were taken to obtain the Kojic acid crystals from local fungal isolation A. flavus WJF81 by separating the fermentation products from the fungus mycelium from the production plant at the centrifuge at a speed of 5000 cycles for 10 minutes. The extraction was followed by ethyl acetate then supernatant concentrate by using rotary evaporator, and dried with heat oven 37ºC. Long, yellowish, pristine acid crystals were obtained that examined the optical microscope with a magnification force of 10x and 40x. The melting point of kojic acid was determined between 152.9-153.5 °C Results of the diagnosis of Kojic acid by applying High pressure liquid chromatography HPLC technique showed that the acid was at one peak, which was close to the

... Show More
View Publication Preview PDF
Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
The Properties of Thermal Waves Affecting Iraq
...Show More Authors

This research aims at studying each of the cold and hot thermal wavelengths affecting
Iraq for a minimum climatic course of 11 years beginning from 1992 till 2002. Three stations
were selected including the parts of Iraq surface: Mosul, Baghdad and Basrah.
The wave days were also connected with the related climatic elements represented by
the wind direction and speeds and the relative humidity. It was shown that Iraq is affected by
the rates of hot thermal wave lengths greatly compared to the rates of cold wavelengths. The
results suggested that the highest rate of hot and cold wavelengths recorded over Basra station
was (3.5) days for the cold and (5) days for the hot. While the lowest rates was at Mosul
station

... Show More
View Publication Preview PDF
Publication Date
Fri Mar 31 2023
Journal Name
2nd International Conference On Mathematical Techniques And Applications: Icmta2021
Annealing effect on structural and optical properties of Sb2S3 thin film
...Show More Authors

The effect of annealing on the structural and optical properties of Antimony trisulfide (Sb2S3) is investigated. Sb2S3 powder is vaporized on clean glass substrates at room temperature under high vacuum pressure to form thin films. The structural research was done with the aid of X-ray diffraction (XRD) and atomic force microscopy (AFM). The amorphous to the polycrystalline transformation of these thin films was shown by X-ray diffraction analysis after thermal annealing. These films' morphology is explained. The absorption coefficient and optical energy gap of the investigated films are calculated using transmission spectra. Both samples have strong absorption in the visible spectrum, according to UV-visible absorption spectra. The optical

... Show More
View Publication Preview PDF
Scopus (5)
Crossref (2)
Scopus Crossref
Publication Date
Mon Dec 11 2017
Journal Name
Al-khwarizmi Engineering Journal
Iraqi Bauxite and Porcalinite Rocks Based Refractory, Preparation and Studying Properties
...Show More Authors

Abstract 

Locally natural occurring Iraqi rocks of Bauxite and Porcelanite (after pre calcinations at 1000oC for 1hr) were used, with the addition of different proportions of MgO and Al2O3, to prepare refractory materials. The effects of these additives on the physical and thermal properties of the prepared refractories were investigated.

Many batches of Bauxite/MgO, Bauxite/Al2O3, Bauxite/MgO/Al2O3, and   Porcelanite/ MgO/Al2O3 were prepared. The mixture is milled and classified into different size fractions; fine (less than 45μm) 40%, middle (45-75μm) 40%, and coarse (75-106μm) 20% .

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Mon Jun 01 2015
Journal Name
The European Physical Journal Applied Physics
A carbon nanotubes photoconductive detector for middle and far infrared regions based on porous silicon and a polyamide nylon polymer
...Show More Authors

View Publication
Scopus (5)
Crossref (4)
Scopus Clarivate Crossref
Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Preparation Adhesive Material Reinforced of Graphite Particles and Study Electrical and Mechanical and Thermal Properties
...Show More Authors

The physical, mechanical, electrical and thermal properties containing (Viscosity, curing, adhesion force, Tensile strength, Lap shear strength, Resistively, Electrical conductivity and flammability) of adhesive material that prepared from Nitrocellulose reinforced with graphite particles and aluminum streat. A comparison is made between the properties of adhesive material with varying percentage of graphite powder (0%, 25%, 30%, 35%, 40%) to find out the effect of reinforcement on the adhesive material. The ability of property an electrical was studied through the measurement of conductivity a function of temperature varying. The results of comparison have clearly shown that the increasing of conten

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Study of structural, optical and electrical properties of thin Ag2Cu2O4 films prepared by pulsed laser deposition
...Show More Authors

The influence of sintering and annealing temperatures on the structural, surface morphology, and optical properties of Ag2Cu2O4 thin films which deposited on glass substrates by pulsed laser deposition method have been studied. Ag2Cu2O4 powders have polycrystalline structure, and the Ag2Cu2O4 phase was appear as low intensity peak at 35.57o which correspond the reflection from (110) plane. Scan electron microscopy images of Ag2Cu2O4 powder has been showed agglomerate of oxide particles with platelets shape. The structure of thin films has been improved with annealing temperature. Atomic Force micrographs of Ag2Cu2O4 films showed uniform, homogenous films and the shape of grains was almost spherical and larger grain size of 97.85 nm has o

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 01 2024
Journal Name
Energy Storage
Comprehensive Study of <scp>PAN</scp>‐<scp>NaBF<sub>4</sub></scp> Solid Polymer Electrolytes: Insights Into Optical, Structural, Thermal, Electrical, and Electrochemical Properties for Sodium‐Ion Batteries
...Show More Authors
ABSTRACT<p>This research explores the use of solid polymer electrolytes (SPEs) as a conductive medium for sodium ions in sodium‐ion batteries, presenting a possible alternative to traditional lithium‐ion battery technology. The researchers prepare SPEs with varying molecular weight ratios of polyacrylonitrile (PAN) and sodium tetrafluoroborate (NaBF<sub>4</sub>) using a solution casting method with dimethyl formamide as the solvent. Through optical absorbance measurements, we identified the PAN:NaBF<sub>4</sub> (80:20) SPE composition as having the lowest energy band gap value (4.48 eV). This composition also exhibits high thermal stability based on thermogravimetric analysis results. </p> ... Show More
View Publication
Scopus (2)
Crossref (3)
Scopus Clarivate Crossref