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joe-2590
Reaction Kinetics of Tert-Butanol Esterification
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In this study, the kinetics for the reaction of tert-butanol esterification with acetic acid in the presence of Dowex 50Wx8 catalyst was investigated. The reaction kinetic experiments were conducted in 1000 milliliter vessel at temperatures ranged from 50 - 80 oC, catalyst loading 25-50 g/L, and the molar ratios of acetic acid to tert-butanol from 1/3 – 3/1. The reaction rate was found to increase with increasing temperature and catalyst loading. It was also found the conversion of the tert-butanol increases as the molar ratio of acid to alcohol increases from 1/3 – 3/1. The Non-ideality of the liquid phase was taken into account by using activities instead of molar fractions. The activity coefficients were calculated according to the group contribution UNIFAC method. The results show that the activation energy of tert-butanol esterification with acetic acid was found to be 1.09 kJ/mol.

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Publication Date
Thu Mar 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Practices of managers and their impact on the contributions of personnel
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This research was based on two pillars. The first is a comparison between of research done and the result of a particular  variable of research  indebendently in the united state, and second, knowledge and determine the effect of managers  practices on the contributions of personnel. The manager and staff are considered to be the most important elements in the organization and all of them  have a duty towards the others which governed by the relationship rules of procedure of the ministry researched, on the one  hand  and the interests of the organization and hence employees , whether executives  or employees within management formations that the availability of an acceptable level of good pract

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Publication Date
Wed Oct 24 2018
Journal Name
Journal Of Economics And Administrative Sciences
The rality of urban management strategies in the city of Baghdad
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Several studies have indicated that more than 600 cities in the world (intermas of rapid growth and development) will generate about 60% of international economic growth between 2010 and 2025 . by 2025 , 66% of the worlds population will live in urban areas the management of cities will face challenges that accompany this increase in the population which requires preparing to face these challenges and problems and the need to provide the aim of the research to know the readiness of Baghdad city to implement the strategies of urban management throught on asmple representing the ( Advisiry group for the comprechnsive development plan for the city of Baghdad 2030 and its supporters ) in the municipality of Baghdad and the number of

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Publication Date
Wed Jan 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Determination of naturally occurring radionuclides in Disi aquifer water of Jordan
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The Disi water samples were collected from different Disi aquifer wells in Jordan using a clean polyethylene container of 10-liter size. A hyper-pure germanium (HPGe) detector with high- resolution gamma-ray spectroscopy and a low background counting system was used for the identification of unknown gamma-rays emitting from radionuclides in the environmental samples. The ranges of specific activity concentrations of 226Ra and 228Ra in the Disi aquifer water were found to be from 0.302 ± 0.085 to 0.723 ± 0.207 and from 0.047 ± 0.010 to 0.525 ± 0.138 Bq L−1, with average values of 0.516 ± 0.090 and 0.287 ± 0.091 Bq L−1, respectively. The average combined radium (226Ra + 228Ra) activity and radium activity ratio (228Ra/226Ra) in Disi

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Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Study of Mechanical Properties of (Al-Cu-Mg) Alloy Matrix Composite
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The present research had dealt with preparing  bars  with the length of about  (13 cm) and  adiametar  of  (1.5 cm) of composite materials with metal  matrix  represented by (Al-Cu-Mg) alloy cast enforced by (ZrO2) particles with chosen weight  percentages (1.5, 2.5 ,3.5, 5.5 %). The base  cast and the composite  materials were prepared by casting method by uses vortex  Technique inorder to  fix up (ZrO2) particles in homogeneous way on  the  base cast. In addition to  that, two main groups of composite materials were prepared depending on the particles size of (ZrO2) , respectively.       &n

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Publication Date
Fri Mar 01 2019
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Additives on The Performance of Hydrostatic Thrust Bearings
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The paper is concerned with, the behavior of the hydrostatic thrust bearings lubricated with liquid-solid lubricants using Einstein viscosity formula, and taking into account the centrifugal force resulting from high speed.  Also studied is the effect of the bearing dimensions on the pressure, flow rate, load capacity, shear stress, power consumption and stiffness.

The theoretical results show an increase in load capacity by (8.3%) in the presence of solid graphite particles with concentration of (16%) by weight as compared with pure oil, with increasing shear stress.  .

In general the performance of hydrostatic thrust bearings improve for load carrying capacity, volume flow rate,

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Publication Date
Sat Mar 01 2008
Journal Name
Iraqi Journal Of Physics
Effect of Pressure on the Properties of HgBa2Ca2Cu3O8+δ HTSC System
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High temperature superconductors with a nominal composition HgBa2Ca2Cu3O8+δ
for different values of pressure (0.2,0.3, 0.5, 0.6, 0.9, 1.0 & 1.1)GPa were prepared by
a solid state reaction method. It has been found that the samples were semiconductor
P=0.2GPa.while the behavior of the other samples are superconductor in the rang
(80-300) K. Also the transition temperature Tc=143K is the maximum at P is equal to
0.5GPa. X-ray diffraction showed a tetragonal structure with the decreasing of the
lattice constant c with the increasing of the pressure. Also we found an increasing of
the density with the pressure.

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Publication Date
Sun Mar 05 2017
Journal Name
Baghdad Science Journal
Histomorphological study of uropygial gland of pekin duck (Anas platyrhnchos domesticus)
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The study included 20 birds of Pekin duck (Anas platyrhnchos domesticus) for study the histological of uropygial gland (10 males + 10 females), the weights were between (1411-1582 gm) for males and (1350-1980 gm) female. Routine Histological Techniques was done and stained by Hematoxylin and Eosin (H&E), Periodic Acidic Schiff (PAS), Masson's trichrome stains. Histological sections of the uropygial gland of Pekin ducks showed that the gland consist of the capsule, parenchyma, isthmus and uropygial papillae. The capsule consist of Dense irregular connective tissue. The mean thickness of capsule around the gland lobes were (56.321?17.206µm) and around the uropygial papillae were (67.208?14.996 µm). The capsule tissues continuous in betwe

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Publication Date
Sun Dec 06 2009
Journal Name
Baghdad Science Journal
Effect of salinity on survival, development and growth of Artemia sp.
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This study aimed to determine the possibility of culturing genus Artemia in under laboratory conditions for locally culturing and producing. Different salinity concentrations were used, ranging from 5-40g/l . the results showed that the concentration 30g/l is the best for hatching. This concentration recorded hatching efficiency of 68800 nauplii/g cysts and hatching percentage of 45.86%, while the concentration 5g/l recorded less hatching efficiency and hatching percentage of 20266 nauplii/g and 13.5% respectively . Investigating the effect of salinity on individuals survival and growth using saline concentrations ranging from 30to 100g/l, revealed that the best percentage was 75.00% in the first week with 70g/l, whilst the best rates of

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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
OIL OF IRAQ AND MULTI-NATIONALITIES COMPANIES "Geopolitical point of view"
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Multi-nationalities companies are the main companies in the progressed
countries that improve the current technology and, thus, become the main source of it.
These companies, in the first place, aim to increase the profits of its
investments to satisfy stock holders in the original countries to which these companies
belong.
It is a mean to interfere in the economic of countries especially the growing
ones and exploit their important natural resources. Since this research focus on the
dangers of these companies, mechanism of its work and its dangers on the most
important natural resources of our country which is oil; therefore, the research
confirm that this important natural treasure must be under an Iraqi cont

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Publication Date
Mon Oct 13 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Incidence of Hodgkin's lymphoma of head and neck in Baghdad city
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Background: Hodgkin's lymphoma (HL), formerly called Hodgkin's diseases is an uncommon form of lymphoma. The incidence of Hodgkin's lymphoma shows marked heterogeneity with respect to age, gender, race, geographic area, social class and histological subtype. This study was carried out in an attempt to evaluate the incidence of Hodgkin's lymphoma of head and neck in Baghdad city. Materials and Methods: The diagnosed cases of Hodgkin's lymphoma of head and neck region in Baghdad city between (1990-1999) were collected and analyzed according to age, gender, site and the histopathological subtypes of the tumor. Results: Out of (702) cases of Hodgkin's lymphoma of ten years between (1990-1999),(362 ) of them were occurred in the head and neck

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