Preferred Language
Articles
/
joe-246
Energy Dissipation on the Ogee Spillways by Using Direction Diverting Blocks
...Show More Authors

The purpose of this study is to evaluate the hydraulic performance and efficiency of using direction diverting blocks, DDBs, fixed on the surface on an Ogee spillway in reducing the acceleration and dissipating the energy of the incoming supercritical flow. Fifteen types of DDB models were made from wood with a triangulate shape and different sizes were used. Investigation tests on pressure distribution at the DDBs boundaries were curried out to insure there is no negative pressures is developed that cause cavitation. In these tests, thirty six test runs were accomplished by using six types of blocks with the same size but differ in apex angle. Results of these test showed no negative pressures developed at the boundaries of these blocks. A physical model for a part of Mandili Dam spillway system was constructed with a scale ratio of 1:50. Thirteen runs were carried out to obtain the rating curve of the ogee weir of Mandili Dam Model. Four hundred and seventy test runs were carried out to investigate the performance of the DDBs in reducing the energy of the flow. In these test runs, nine types of blocks with different sizes and different apex angles installed with different configurations on the spillway surface. Thirteen configurations of DDBs were tested. The Froude Number and the location of the hydraulic jump were used as indicators for the efficiency of these DDBs. Results indicated that when using the DDBs on a spillway surface, less Froude Number downstream the spillway is obtained and the hydraulic jump occurs at a much shorter distance from the spillway toe compared to same spillway without DDBs. Depending on the DDBs type, configuration, and the applied discharge, the obtained reduction in Froude Number varied between 4.4 to 19.3% and the reduction in the hydraulic jump distance measured from the spillway toe varied between 54% and 76% compared with that of the standard design of Mandili Dam. 

 

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Sep 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Synthesized 2nd Generation Zeolite as an Acid-Catalyst for Esterification Reaction
...Show More Authors

MCM-48 zeolites have unique properties from the surfaces and structure point of view as it’s shown in the results ,and unique and very sensitive to be prepared, have been experimentally prepared and utilized as a second-generation/ acid - catalyst for esterification reactions of oleic acid as a model oil for a free fatty acid source with Ethanol. The characterization of the catalyst used in the reaction has been identified by various methods indicating the prepared MCM-48 is highly matching the profile of common commercial MCM-48 zeolite. The XRF results show domination of SiO2 on the chemical structure with 99.1% and  agreeable with the expected from MCM-48 for it's of silica-based, and the SEM results show the cubic c

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Sat Jan 30 2016
Journal Name
Ibn Al-haitham J. For Pure & Appl. Sci.
Study of Some Structural and Optical Properties of AgAlSe2 Thin Films
...Show More Authors

The structural properties of ternary chalcopyrite AgAlSe2 compound alloys and thin films that prepared by the thermal evaporation method at room temperature on glass substrate with a deposition rate (5±0.1) nm s-1 for different values of thickness (250,500 and 750±20) nm, have been studied, using X-ray diffraction technology. As well as, the optical properties of the prepared films have been investigated. The structural investigated shows that the alloy has polycrystalline structure of tetragonal type with preferential orientation (112), while the films have amorphous structure. Optical measurement shows that AgAlSe2 films have high absorption in the range of wavelength (350-700 nm). The optical energy gap for allowed direct transition we

... Show More
Preview PDF
Publication Date
Sun Sep 22 2019
Journal Name
Baghdad Science Journal
Spectral Properties of Hybrid of Rhodamine (6G) Dyes Doped Epoxy Resin Dissolved in Chloroform
...Show More Authors

            The research is dealing with the absorption and fluorescence spectra for the hybrid of  an Epoxy Resin doped with organic dye Rhodamine (R6G) of different concentrations (5*10-6, 5*10-5, 1*10-5, 1*10-4, 5*10-4) Mol/ℓ at room temperature. The Quantum efficiency Qfm, the rate of fluorescence emission Kfm (s-1), the non-radiative lifetime τfm (s), fluorescence lifetime τf and the Stokes shift were calculated. Also the energy gap (Eg) for each dye concentration was evaluated. The results showed that the maximum quantum effi

... Show More
View Publication Preview PDF
Scopus (4)
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Tue Oct 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Determine Most Stable Isobar for Nuclides with A= (15-30) & (101- 115)
...Show More Authors

In this study the most stable isobar for some isobaric families (light and  intermediate ) nuclei with mass number (A) equals to (15-30) & (101- 115) have been determined. This determination of stable nuclide can help to determine the suitable nuclide, which can be used in different fields.

Most stable isobar can be determined by two means. First: plot mass parabolas (plotting the binding energy (B.E) as a function of the atomic number (Z)) for these isobaric families, in this method most stable isobars represent the lowest point in mass parabola (the nuclide with the highest value of binding energy).

Second: calculated the atomic number for most stable isobar (ZA) value.

Our results show that

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Jan 25 2023
Journal Name
Molecular Simulation
Engineering promising A-Ï€-D type molecules for efficient organic-based material solar cells
...Show More Authors

Within this work, to promote the efficiency of organic-based solar cells, a series of novel A-π-D type small molecules were scrutinised. The acceptors which we designed had a moiety of N, N-dimethylaniline as the donor and catechol moiety as the acceptor linked through various conjugated π-linkers. We performed DFT (B3LYP) as well as TD-DFT (CAM-B3LYP) computations using 6-31G (d,p) for scrutinising the impact of various π-linkers upon optoelectronic characteristics, stability, and rate of charge transport. In comparison with the reference molecule, various π-linkers led to a smaller HOMO–LUMO energy gap. Compared to the reference molecule, there was a considerable red shift in the molecules under study (A1–A4). Therefore, based on

... Show More
View Publication
Crossref (1)
Scopus Clarivate Crossref
Publication Date
Thu Mar 09 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study of Some Structural and Optical Properties of AgAlSe2 Thin Films
...Show More Authors

  The structural properties of ternary chalcopyrite AgAlSe2 compound alloys and thin films that prepared by the thermal evaporation method at room temperature on glass substrate with a deposition rate (5±0.1) nm s-1 for different values of thickness (250,500 and 750±20) nm, have been studied, using X-ray diffraction technology. As well as, the optical properties of the prepared films have been investigated. The structural investigated shows that the alloy has polycrystalline structure of tetragonal type with preferential orientation (112), while the films have amorphous structure. Optical measurement shows that AgAlSe2 films have high absorption in the range of wavelength (350-700 nm). The optical energy gap for allowed direct

... Show More
View Publication Preview PDF
Publication Date
Mon Mar 23 2020
Journal Name
Journal Of Engineering
Improving Photovoltaic Panel (PV) Efficiency via Two Axis Sun Tracking System
...Show More Authors

In this paper two axis sun tracking method is used to absorb maximum power from the sun's rays on the solar panel via calculating the sun’s altitude and azimuth angles, which describe the solar position on the Iraqi capital Baghdad for the hours 6:00, 7:00, 8:00, 9:00, 12:00, 15:00 and 17:00 per day. The angles were calculated in an average approach within one month, so certain values were determined for each month. The daily energy achieved was calculated for the solar tracking method compared with the fixed tracking method. Designed, modeled and simulated a control circuit consisting of reference position truth table, PI Controller and two servomotors that tracked the sun position to adjust the PV panel perpendicular

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sat Sep 01 2018
Journal Name
International Journal Of Renewable Energy Research
Performance of Wind Turbines at Three Sites in Iraq
...Show More Authors

Matching between wind site characteristics and wind turbine characteristics for three selected sites in Iraq was carried out. Site-turbine matching for potential wind power application in Iraq has not yet been well reported on. Thus, in this study, five years’ wind speed data for sites located in Baghdad (33.34N, 44.40E), Nasiriyah (31.05N, 46.25E), and Basrah (30.50N, 47.78E) were collected. A full wind energy analysis based on the measured data, Weibull distribution function, and wind turbine characteristics was made. A code developed using MATLAB software was used to analyse the wind energy and wind turbines models. The primary objective was to achieve a standard wind turbine-site matching based on the capacity factor. Another matching

... Show More
View Publication
Crossref (1)
Crossref
Publication Date
Mon Jun 19 2023
Journal Name
Journal Of Engineering
Manufacturing an Organic Solar Cell and Comparing with Different Dyes
...Show More Authors

A solar cell was manufactured from local materials and was dyed using dyes extracted from different organic plants. The solar cell glass slides were coated with a nano-porous layer of Titanium Oxide and infused with two types of acids, Nitric acid and Acetic acid. The organic dyes were extracted from Pomegranate, Hibiscus, Blackberry and Blue Flowers. They were then tested and a comparison was made for the amount of voltage they generate when exposed to sunlight. Hibiscus sabdariffa extract had the best performance parameters; also Different plants give different levels of voltage.

View Publication Preview PDF
Crossref
Publication Date
Fri Jun 24 2022
Journal Name
Iraqi Journal Of Science
Spectral Analysis of Remote Sensing Data
...Show More Authors

In the present work, different remote sensing techniques have been used to analyze remote sensing data spectrally using ENVI software. The majority of algorithms used in the Spectral Processing can be organized as target detection, change detection and classification. In this paper several methods of target detection have been studied such as matched filter and constrained energy minimization.
The water body mapping have been obtained and the results showed changes on the study area through the period 1995-2000. Also the results that obtained from applying constrained energy minimization were more accurate than other method comparing with the real situation.

View Publication Preview PDF