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Energy Dissipation on the Ogee Spillways by Using Direction Diverting Blocks
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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. 

 

 

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Publication Date
Wed Jun 30 2010
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Study on Vanadium Recovery from Spent Catalyst Used in the Manufacture of Sulfuric Acid
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Spent catalysts for sulfuric acid production have large amount of vanadium and due to environmental authority it is required to reduce the vanadium contain of the spent catalyst. Experimental investigation was conducted to study the vanadium recovery from spent catalyst via leaching process using sodium hydroxide to study the effect of process variables (temperatures, sodium hydroxide molarities, leaching time and particle size) on vanadium recovery. The effect of process variables (temperature, particle size,molarities of sodium hydroxide and leaching time) on the percentages of vanadium recovery were investigated and discussed .It was found that the percentage of vanadium recovery increased with increasing temperature up to 100 , incre

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Publication Date
Thu Dec 03 2020
Journal Name
Almaarif University College
The effect of food additives (Monosodium Glutamate-MSG) on human health-A Critical Review
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According to the famous saying of the medieval physician Paracelsus, "There is no substance without poison. Only the dose determines the extent of the toxic effect." Here, the effect of monosodium glutamate (MSG) on human health and the risks to the health of its frequent use in the short term was addressed and the long term was evaluated according to the studies of several researchers specializing in this regard. Monosodium glutamate (MSG) is known as one of the most popular food additives that classified as a flavor enhancer. Parts of the evidence were reviewed from the literature explaining its effect on immune system cells in addition to metabolic disorders by exposing individuals to obesity and what is known as metabolic syndrome, as w

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Publication Date
Thu Nov 08 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
The effect of mouth rinses on surface micro hardness of two esthetic restorative materials
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Objective: To evaluate the effect of mouth rinses (Biofresh and ZAK) on the surface micro hardness
of two light cure restorative material (Tetric ceram ivoclar-vivadent) and (3M Z 250) dental
composite.
Methodology: The microhardness values of (sixty) composite specimens were measured at the top
surfaces after 24 hours of immersion in different solutions (Biofresh, Zak mouth wash and distilled
water as control). Comparison done using descriptive statistics (mean, SD, SEM, minimum and
maximum values) and inferential statistics (ANOVA and LSD) test.
Results: The biofresh mouth rinse which has high alcohol containing has less effect on
microhardness of tetric ceram than the zak &distiled water , while the effect

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Publication Date
Thu Dec 28 2023
Journal Name
Al–bahith Al–a'alami
Effect of Political Factors on the Performance of Specialized Journalists in Iraqi Electronic Journalism
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This study aimed to identify the political factors influencing the performance of specialized journalists in Iraqi electronic newspapers. The significance of the study stems from the role of communication in newspapers that have established themselves in reality due to their wide dissemination, multiple uses, expanding freedom base, and the current diversity in perspectives. These newspapers highlight and publish societal issues of concern. The importance of these newspapers is associated with their creators who face various factors affecting their value and performance, whether positively or negatively. In light of this, the political factor was identified as the primary driver for other influencing factors. The

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Publication Date
Sun Feb 28 2021
Journal Name
Journal Of Economics And Administrative Sciences
The impact of complexity management on dynamic capabilities: a survey at some private colleges
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This research aims to understand complexity management and its impact on the use of the dynamic capabilities of a sample of private colleges.  Private colleges are currently facing many crises, changes, unrest and high competitive pressures.  Which is sometimes difficult or even impossible to predict.  The recruitment of dynamic capabilities is also one of the challenges facing senior management at private colleges to help them survive and survive.  Thus, the problem of research was (there is a clear insufficiency of interest in Complexity Management and trying to employ it in improving the dynamic capabilities of Colleges that have been discussed?). A group of private colleges was selected as a

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Crossref
Publication Date
Mon Dec 18 2017
Journal Name
Al-khwarizmi Engineering Journal
The Effect of Magnetic Field with Nanofluid on Heat Transfer in a Horizontal Pipe
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This work presents an experimental study of heat transfer and flow of distilled water and metal oxide nanofluid Fe3O4-distilled water at concentrations of (φ = 0.3, 0.6, 0.9 %) by volume in a horizontal pipe with constant magnetic field. All the tests are carried out with Reynolds number range (2900-9820) and uniform heat flux (11262-19562 W/m2). The results show that, the nanofluid concentration and magnetic intensity increase, the Nusselt number increases. The maximum enhancement in Nusselt number with magnetic nanofluid is (5.4 %, 26.4 %, 42.7 %) for volume concentration (0.3, 0.6, 0.9 %) respectively. The enhancement is maximized with magnetic intensity (0.1, 0.2, 0.3 tesla) respectively to (43.9, 44

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Publication Date
Fri Aug 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Preventive measures for banking supervision on money laundering (Search in the Gulf Commercial Bank)
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The research aims to study and assess the effectiveness of preventive measures banking for the reduction of money laundering based on the checklist (Check list), which have been prepared based on the paragraphs of some of the principles and recommendations of international and Money Laundering Act No. 93 of 2004 and the instructions thereto, to examine and assess the application of these measures by Gulf Commercial Bank, which was chosen to perform the search.

I've been a statement the concept of money laundering in terms of the definition and characteristics, stages and effects of political, economic and social as well as the nature of banking supervision in terms of the definition and the most important

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Crossref
Publication Date
Wed Jan 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Influence of CFRP Strengthening on the Behavior of Concavely-Curved Soffit Concrete Bridge Girders
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Abstract<p>Over the last few decades, fiber reinforced polymer (FRP) has been increasingly used in strengthening different structural concrete members. The main objective of this research is to study the influence of curvature on the performance of curved soffit reinforced concrete (RC) bridge girders that have been strengthened with carbon fiber reinforced polymers (CFRP). This experimental program was designed to evaluate the effect of concavity and soffit curvature on the CFRP laminate utilization and load capacity, compared to flat soffit RC beams strengthened with the same CFRP system. Accordingly, five beams, 2.7 m in length and having the same degree of soffit curvature (20 mm per 1 meter</p> ... Show More
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Crossref
Publication Date
Sat Aug 01 2020
Journal Name
Iop Conference Series: Materials Science And Engineering
Effects of Sandy Soil-structure Interaction on the Natural Period of RC Building Frames
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Abstract<p>Building natural period, T, is a key character in building response for wind and seismic induced forces. In design practice, the period, T, is either estimated from empirical relations proposed by the design codes or determined from analytical or numerical models. The effect of the soil-structure interaction is usually neglected in the design practice and analysis models. This paper uses a sophisticated finite element simulation to investigate the effect of soil-structure modeling on the fundamental period of RC buildings subjected to wind and seismic induced forces. A typical interior building frame has been imitated using the frame element for beams and columns with constrains to mo</p> ... Show More
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Scopus Crossref
Publication Date
Thu Nov 11 2021
Journal Name
Aip Conf. Proc
Effect of cobalt Ions precursor on the nanostructure of sprayed cobalt oxide thin films
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In this study, Cobalt Oxide nanostructure was successfully prepared using the chemical spray pyrolysis technique. The cobalt oxide phase was analysed by X-ray Diffraction (XRD) and proved the preparation of two cobalt oxide phases which are Co3O4 and CoO phases. The surface morphology was characterized by Scanning Electron Microscope (SEM) images showing the topography of the sample with grain size smaller than 100 nm. The optical behavior of the prepared material was studied by UV-Vis spectrophotometer. The band gap varied as 1.9 eV and 2.6 eV for Co3O4 prepared from cobalt sulphate precursor, 2.03 eV and 4.04 eV for Co3O4 prepared from cobalt nitrate precursor, 2.04 eV and 4.01 eV for CoO prepared from cobalt chloride precursor where th

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Scopus