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ijs-3967
Effect of Spheroidization Treatment on Friction Stir Processing of Al- 14 wt.% Si Alloy
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    Three different rotational speeds (800, 1000 and 1250 rpm) and traverse speeds of (0.42 mm/sec) at a constant taped pin have been employed to produce the stir zones generated from friction stir processing (FSP) of near eutectic Al- 14 wt.% Si alloy. The processed samples were thoroughly analyzed macroscopically and microscopically. The as-cast microstructure of eutectic (α Al+ Si) and primary Si were fragmented to produce spheroidization of small size of Si and deformed matrix. The stir zones showed an increase in hardness from around 45-50 Hv for as-cast to 40-65 depending on the variables applied. All the processed samples were characterized by advanced and retreated regions with large single piping defects formed mainly at the retreated region. High temperature spheroidization at 500 oC with two soaking times of 10 and 20 hrs was applied for the processed sample of 1000 rpm to investigate the effect of heat treatment on the silicon fragmentation and hardness. Growth and fragmentation of Si have taken place at soaking time of 10 hrs. At soaking time of 20 hrs noticeable microvoids and macrovoids were formed at the stir zones.  Microhardness of both the advancing and the retreating regions decreased with increasing soaking time.

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Publication Date
Thu Dec 28 2017
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Increasing Carbon Concentration Increasing on the Mechanical Properties of TiCx Thin Films
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Carbides or nitrides thin films present materials with good mechanical properties for industrial applications as they can be coatings at low temperatures serve temperature sensitive surfaces. In this work the effect of the C percentage on the mechanical properties represented by the Young modulus (E) of combinatorial magnetron sputtered TiCx (34%x˂65%) has been studied. The structure of the produced films is TiC independent on the C concentration. The mechanical properties are increased with increasing the C concentration up to 50%, and then decreasing with further C % increasing. These results can be explained by considering the resultant residual stresses.

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Publication Date
Sat Jan 20 2024
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Effect of Mycorrhizal Inoculation and Fertilization with Plant Residues on the Growth of Chard Plant
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In order to study the effect of inoculation with mycorrhiza and fertilization with plant residues on the growth of plants, we used two factors: the first two levels of mycorrhiza inoculation, Glumus mossea (0 and 10 g.pot-1) and the second factor, four levels of plant residues (10 g.pot-1) celery plant residues, 10 g pot-1 mint residues, and 10 g pot-1 black bean seed residues. Mychorrizal treatment (10 g pot-1) increased the number of mycorrhiza spores and the infection percentage of mycorrhizal by 917.44% and 13088.23%, respectively; celery treatment (10 g.pot-1) increased the chlorophyll index in the leaves and height of the chard plant by 31.34% and 94.04%, re

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
On The Dynamical Behavior of a Prey-Predator Model With The Effect of Periodic Forcing
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The dynamical behavior of a two-dimensional continuous time dynamical system describing by a prey predator model is investigated. By means of constructing suitable Lyapunov functional, sufficient condition is derived for the global asymptotic stability of the positive equilibrium of the system. The Hopf bifurcation analysis is carried out. The numerical simulations are used to study the effect of periodic forcing in two different parameters. The results of simulations show that the model under the effects of periodic forcing in two different parameters, with or without phase difference, could exhibit chaotic dynamics for realistic and biologically feasible parametric values.

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
The effect of unsecured use of chemical pesticides on the environment and health in Iraq
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The wide use of pesticides in recent years leads to rapid distribution of these pollutants in the environment (air, water and soil).They were transported by means of air or water to biological ecosystems. They become more toxic through the processes of biological magnification while some of them persist for along period.The aim of this work is to show the negative effect that chemical pesticides causes, and in the same to show their side effect on the environment and health in Iraq. We could conclude that the bad use of these chemicals could cause an urgent impact now or in the future. Governmental offices dealing with these materials should take the right measures to minimize the danger and the misuse of these chemicals by seeking alternat

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Study the Effect of thickness on the Optical Properties Performance of active polymeric laser media
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The paper include study the effect thickness of the polymeric sample which is manufactured by thermo press way. The sample was used as an active tunable R6G laser media. The remarks show that, when the thickness of the samples is increased, with the same concentration, the spectrum will shift towards the short wavelength, & the quantum fluorescence yield will increased. The best result we obtained for the quantum fluorescence yield is (0.68) at the sample, with thickness (0.304mm) in Ethanol solvent, while when we used the Pure Water as a solvent, we found that the best quantum fluorescence yield is (0.63) at (0.18mm) thickness of the sample.

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Publication Date
Wed May 10 2023
Journal Name
Journal Of Planner And Development
The effect of urban obsolescence on the quality of the built environment for historical quarters
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             The centers of cities and historical quarter are exposed to a severe threat to the values of the physical and legal urban environment as a result of the value deterioration and the emergence, emergence and spread of new values on the intellectual and urban context, which generates the loss of the urban environment for its spatio-temporal continuity, flexibility, adaptation and continuity, and thus urban obsolescence, Hence the problem of the research in “the lack of comprehensiveness of studies on the phenomenon of urban obsolescence and its impact on the decline in the values of the quality of the built environment in historic

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Publication Date
Sun Dec 30 2007
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Effect of Feed Concentration on the Production of Pregelatinized Starch in a Double Drum Dryer
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Double drum dryer is operated for producing pregelatinized maize starches using feed starch slurries of different
solids(7, 10 and13 g/100 g )content . Steam pressure (2,3,and 4 bar), the level of pool between the drums (4,7,and 10
cm) , and speed of drums rotation (3,4,and 6 rpm) are varied together with the feed solids content in a practical range of
values. The response of the dryer is registered by measuring several output variables, i.e. external drum temperature,
product moisture content, mass flow rate.

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Publication Date
Sun Sep 04 2011
Journal Name
Baghdad Science Journal
The effect of Sodium deoxycholate on the production of Newcastle virus inoculated in chorioallantoic membrane
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Newcastle Disease is one of the most important disease world wide distributions which invade the flock in different age resulting in large economic losses. This study aimed to evaluate the effect of treatment with 4 different concentrations (0.25, 0.5, 1.0 and 2.0 %) of Sodium deoxycholate (SDC) on the vaccinal virus (La Sota) using inoculation in the fragments of Chorioallantoic membrane. The treatment with each of the above 4 concentrations of SDC resulted in an increase in the Hemagglutination titer (HA) of the virus (28, 29.6, 211.6, 214.6) respectively as compared to the HA titer value for the untreated virus (26.6). No significant differences were noticed among all concentrations with regard to their effect on the HA titer, except

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Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
The Effect of Fluorine and Hydrogen Concentrations on the Chain Reaction of HF Chemical Laser
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A numerical investigation has been performed to examine the effect of fluorine concentration on the chain reaction mechanisms and parameters of hydrogen fluoride (HF) chemical laser. The practical difficulties associated with this type of lasers impose that an alternative route might be quite useful. Thus, particular attention was paid to develop a computer program to investigate various processes. The results of this computer simulation program proved their credibility when compared with the little published data. This computer program is called Reaction Rate Simulation Model (RRSM). An entirely new approach to emulate the reaction mechanisms has been followed. The effectiveness of reaction rates in the processes of HF lase

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Publication Date
Sat Jan 01 2011
Journal Name
Iraqi Journal Of Physics
Study of annealing effect on some Optical Properties of CuIn(SexTe1-x)2 Thin Films
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The optical properties for the components CuIn(SexTe1-x)2 thin films with both values of selenium content (x) [0.4 and 0.6] are studied. The films have been prepared by the vacuum thermal evaporation method with thickness of (250±5nm) on glass substrates. From the transmittance and absorbance spectra within the range of wavelength (400-900)nm, we determined the forbidden optical energy gap (Egopt) and the constant (B). From the studyingthe relation between absorption coefficient (α) photon energy, we determined the tails width inside the energy gap.
The results showed that the optical transition is direct; we also found that the optical energy gap increases with annealing temperature and selenium content (x). However, the width of l

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