Preferred Language
Articles
/
jih-883
A Theoretical Investigation of Enhanced Thermoelectric Figure of Merit of Low-Dimensional Structures
...Show More Authors

 The power factors and electronic thermal conductivities in bismuth telluride (Bi2Te3), lead-telluride (PbTe), and gallium arsenide (GaAs) at room temperature (300K) quantum wires and quantum wells are theoretically investigated. Our formalism rigorously takes into account modification of these power factors and electronic thermal conductivities in free-surface wires and wells due to spatial confinement. From our numerical results, we predict a significant increase of the power factor in quantum wires with diameter w=20 Ã…. The increase is always stronger in quantum wires than in quantum wells of the corresponding dimensions. An unconfined phonon distribution assumed based on the bulk lattice thermal conductivity is then employed to evaluate the possible enhancement of the thermoelectric figure of merit. The electronic thermal conductivity of a 20Ã… diameter wire and a 20Ã… layer thickness is found to be of no significant decrease. The resultant ZT, calculated for Bi2Te3, PbTe and GaAs, quantum wires and quantum wells, showed increase significantly. The additional thermoelectric figure of merit enhancement is mostly due to the two- and one-dimensional carrier confinement which lead to the enhancement of power factor.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Jan 01 2020
Journal Name
Journal Of Radiation Research And Applied Sciences
Theoretical formula for the cosmic-ray muon attenuation coefficients of Pb, Cu, Zn, and Al
...Show More Authors

View Publication
Crossref (2)
Clarivate Crossref
Publication Date
Mon Jan 01 2024
Journal Name
Journal Of Medicine And Life
Antimicrobial photodynamic therapy using a low-power 650 nm laser to inhibit oral Candida albicans activity: an in vitro study
...Show More Authors

Scopus
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
DESIGN, CONSTRUCTION AND TESTING OF LOW SPEED WIND TUNNEL WITH ITS MEASUREMENT AND INSPECTION DEVICES
...Show More Authors

A low speed open circuit wind tunnel has been designed, manufactured and constructed at the
Mechanical Engineering Department at Baghdad University - College of Engineering. The work is one of
the pioneer projects adapted by the R & D Office at the Iraqi MOHESR. The present paper describes the
first part of the work; that is the design calculations, simulation and construction. It will be followed by a
second part that describes testing and calibration of the tunnel. The proposed wind tunnel has a test
section with cross sectional area of (0.7 x 0.7 m2) and length of (1.5 m). The maximum speed is about (70
m/s) with empty test section. The contraction ratio is (8.16). Three screens are used to minimize flow
distu

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Mon Jul 14 2025
Journal Name
Journal Of Engineering
DESIGN, CONSTRUCTION AND TESTING OF LOW SPEED WIND TUNNEL WITH ITS MEASUREMENT AND INSPECTION DEVICES
...Show More Authors

A low speed open circuit wind tunnel has been designed, manufactured and constructed at the Mechanical Engineering Department at Baghdad University - College of Engineering. The work is one of the pioneer projects adapted by the R & D Office at the Iraqi MOHESR. The present paper describes the first part of the work; that is the design calculations, simulation and construction. It will be followed by a second part that describes testing and calibration of the tunnel. The proposed wind tunnel has a test section with cross sectional area of (0.7 x 0.7 m2) and length of (1.5 m). The maximum speed is about (70 m/s) with empty test section. The contraction ratio is (8.16). Three screens are used to minimize flow disturbances in the test section.

... Show More
View Publication
Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Adsorption of Chromium (Vi) from Aqueous Solutions using Low Cost Adsorbent: Equilibrium and Regeneration Studies
...Show More Authors

The adsorption of Cr (VI) from aqueous solution by spent tea leaves (STL) was studied at different initial Cr (VI) concentrations, adsorbent dose, pH and contact time under batch isotherm experiments The adsorption experiments were carried out at 30°C and the effects of the four parameters on chromium uptake to establish a mathematical model description percentage removal of Cr (VI). The
analysis results showed that the experimental data were adequately fitted to second order polynomial model with correlation coefficients for this model was (R2 = 0.9891). The optimum operating parameters of initial Cr (VI) concentrations, adsorbent dose, pH and contact time were 50 mg/l, 0.7625 g, 3 and 100 min, respectively. At these conditions, th

... Show More
View Publication Preview PDF
Crossref (5)
Crossref
Publication Date
Tue May 01 2018
Journal Name
Photomedicine And Laser Surgery
In Vitro Influence of Low-Power Diode Laser Irradiation Time on Human Red Blood Cells
...Show More Authors

Objective: The present study investigates whether the exposure to low-power diode laser induces denaturation in red blood cell (RBC) membrane protein composition, and determines the irradiation time for when denaturation of membrane protein process begins. Background: A low-energy laser has been used extensively in medical applications. Several studies indicated significant positive effects of laser therapy on biological systems. In contrast, other studies reported that laser induced unwanted changes in cell structure and biological systems. The present work studied the effect of irradiation time of low-power diode laser on the structure of membrane proteins of human RBCs. Materials and methods: The RBC suspension was divided into five equa

... Show More
View Publication
Scopus (4)
Scopus
Publication Date
Sun Dec 01 2019
Journal Name
2019 Ieee Asia-pacific Conference On Computer Science And Data Engineering (csde)
Effect of Lime, Cement, and Lime-Cement Stabilisation on Low to Medium Plasticity Clayey Soil
...Show More Authors

View Publication
Scopus (7)
Crossref (5)
Scopus Crossref
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Adsorption of Levofloxacine Antibacterial from Contaminated Water by Non – Conventional Low Cost Natural Waste Materials
...Show More Authors

An experimental study was conducted with low cost natural waste adsorbent materials, barley husks and eggshells, for the removal of Levofloxacine (LEVX) antibacterial from synthetic waste water. Batch sorption tests were conducted to study their isothermal adsorption capacity and compared with conventional activated carbon which were, activated carbon > barley husks > eggshells with removal efficiencies 74, 71 and 42 % with adsorbents doses of 5, 5 and 50 g/L of activated carbon, barley husks, and eggshells respectively. The equilibrium sorption isotherms had been analyzed by Langmuir, Freundlich, and Sips models, and their parameters were evaluated. The experimental data were correlated well with the Langmuir model which gives the

... Show More
View Publication Preview PDF
Crossref (12)
Crossref
Publication Date
Thu Sep 12 2019
Journal Name
Al-kindy College Medical Journal
Evaluation of obesity, smoking, and sedentary lifestyle associations with low back pain in young adults
...Show More Authors

Background: low back pain is one of the most common public health problems and of the most common musculoskeletal complaint. Many risk factors have been considered for developing low back pain include smoking, obesity and sedentary lifestyle.

Aim of study: To evaluate smoking, obesity, and sedentary lifestyle associations with low back pain in young adults aged (18 – 39 years).

Methods: a comparative cross sectional study for young adults aged 18 – 39 years, participants with low back pain as a symptom constitutes the first group, others free of this symptom considered as the control group. Age and gender matched in both groups. Smoking, obesity and sedentary life sty

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Thu Apr 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Theoretical Study of the Effects Type of Host’s Crystal on the Lasing Output of High – Power Thin –Disk Laser
...Show More Authors

Ytterbium-doped (Y2O3), (Sc2O3) and (YAG) crystals are very important for high-power thindisk lasers. These lasers have shown their ability to operate quasi-three-level materials with high
efficiency as well as high thermal conductivity ratio for crystalline hosts. All these reasons have
required studying this type of laser. In the present work, the analytical solution was found for the
equation of laser output power, pumping threshold power, and efficiency of a quasi-three-level
thin disk laser. The numerical solution of these equations was also found through the Matlab
program at the fundamental transverse mode, at a temperature of 299K0
and with high pumping
capabilities in order to know the e

... Show More
View Publication Preview PDF
Crossref