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Stability and thermophysical properties of non-covalently functionalized graphene nanoplatelets nanofluids
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A pioneering idea for increasing the thermal performance of heat transfer fluids was to use ultrafine solid particles suspended in the base fluid. Nanofluids, synthesized by mixing solid nanometer sized particles at low concentrations with the base fluid, were used as a new heat transfer fluid and developed a remarkable effect on the thermophysical properties and heat transfer coefficient. For any nanofluid to be usable in heat transfer applications, the main concern is its long-term stability. The aim of this research is to investigate the effect of using four different surfactants (sodium dodecyl benzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), cetyl trimethylammonium bromide (CTAB), and gum Arabic (GA)), each with three different concentrations, and five ultrasonication times (15, 30, 60, 90, and 120 min) on the stability of water-based graphene nanoplatelets (GNPs) nanofluids. In addition, the viscosity and thermal conductivity of the highest stability samples were measured at different temperatures. For this aim, nineteen different nanofluids with 0.1 wt% concentration of GNPs were prepared via the two-step method. An ultrasonication probe was utilized to disperse the GNPs in distilled water. UV–vis spectrometry, zeta potential, average particle size, and Transmission Electron Microscopy (TEM) were helpful in evaluating the stability and characterizing the prepared nanofluids. TEM and zeta potential results were in agreement with the UV–vis measurements. The highest nanofluid stability was obtained at 60-min ultrasonication time. The prepared water-based pristine GNPs nanofluids were not stable, and the stability was improved with the addition of surfactants. The presence of SDBS, SDS, and CTAB surfactants in the nanofluids resulted in excessive foam. The best water-based GNPs nanofluid was selected in terms of better stability, higher thermal conductivity, and lower viscosity. From all the samples that were prepared in this research, the (1–1) SDBS–GNPs sample with 60-min ultrasonication showed the highest stability (82% relative concentration after 60 days), the second better enhancement in the thermal conductivity of the base fluid (8.36%), and nearly the lowest viscosity (7.4% higher than distilled water).

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Publication Date
Sun Jul 06 2014
Journal Name
Journal Of Educational And Psychological Researches
Fabrication Mind And The Effect With American Dision –adopt
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Is the subject of the mind took a dimension in philosophy and psychology , and has cared psychologists this topic to a large extent , I started education institutions interest in the capabilities of intelligence since the early twentieth century , and the development of interest in them until he arrived to find Standards and Criteria to identify the degree IQ of any individual , and began to educational institutions interested in mental talent and talented .

The United States is the country chock first of these research projects , but they devoted all their attention on the wish talent mental and Gifted , until I got to the projects, the so-called time ( ( wars of the mind ) ) and projects Schools gifted

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Publication Date
Wed Aug 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Privatization Thesis and its trends in Iraq after 2003
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The concept of privatization is built on the basis of the transfer of assets and services of the public sector to the private sector this concept has appeared in the eighties of the last century whene the high oil prices took place and recession solution swept the world Which called for the freedom of the market and left the room for the private sector to take the initiatine in economic activity.         Both the IMF have   adopted this thesis in their programs of the structural adjustment in light of external and internal factors helped to Create the conditions to accept thesis that under the pretext of achieving a number of economic goals.

In Iraq in spite of

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Publication Date
Mon Jul 06 2020
Journal Name
International Journal Of Research In Pharmaceutical Sciences
Teenage pregnancy. Prevalence and adverse outcomes in Baghdad city
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Pregnancy at an early age of life is a major challenge. The consequences of this problem have an impact on the quality of life of the young mother and her family, and determines an important risk for her offspring. The son of a teenage mother has, in general, greater risks than that of a mother of more than 20 years. The aim of this study is to determine the prevalence and outcome of teenage pregnancy. A descriptive data base study was conducted at Al-Elwia Maternity Teaching hospital in the period from January 1, 2019 to the end of June 2019 within the age between 12 and 19 years old. The mean age of the mother was 17.4 ±1.5 years. The mean age of the father was 23.9 ± 5.7 years with (69.5%) with Vaginal delivery and most of the

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Publication Date
Mon Dec 05 2022
Journal Name
Baghdad Science Journal
Cloud Data Security through BB84 Protocol and Genetic Algorithm
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In the current digitalized world, cloud computing becomes a feasible solution for the virtualization of cloud computing resources.  Though cloud computing has many advantages to outsourcing an organization’s information, but the strong security is the main aspect of cloud computing. Identity authentication theft becomes a vital part of the protection of cloud computing data. In this process, the intruders violate the security protocols and perform attacks on the organizations or user’s data. The situation of cloud data disclosure leads to the cloud user feeling insecure while using the cloud platform. The different traditional cryptographic techniques are not able to stop such kinds of attacks. BB84 protocol is the first quantum cry

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Scopus (7)
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Publication Date
Mon Jun 01 2020
Journal Name
Journal Of Engineering
Pilot Based Channel Estimation and Synchronization in OFDM System
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Channel estimation and synchronization are considered the most challenging issues in Orthogonal Frequency Division Multiplexing (OFDM) system. OFDM is highly affected by synchronization errors that cause reduction in subcarriers orthogonality, leading to significant performance degradation. The synchronization errors cause two issues: Symbol Time Offset (STO), which produces inter symbol interference (ISI) and Carrier Frequency Offset (CFO), which results in inter carrier interference (ICI). The aim of the research is to simulate Comb type pilot based channel estimation for OFDM system showing the effect of pilot numbers on the channel estimation performance and propose a modified estimation method for STO with less numb

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Publication Date
Sun Feb 10 2019
Journal Name
Journal Of The College Of Education For Women
The Relations Between Ottoman State and Egypt (1863 – 1879)
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Facts and information contained showing in axes Find Egyptian Ottoman relations
(1863-1879), has gone through stages varying between tides, has witnessed the Khedive
Ismail three sultans Ottomans were Abdul Aziz Murad V, Abdul Hamid II, and since the
Khedive Ismail to judge sought to expand independence Egypt access to many privileges of
the sovereign on Egypt Ottoman Empire, in order to reach the country to independence, has
been chosen by the payment of money and gifts to gain independence, without resorting to
arms, and from this point of Khedive make a lot of money to get the privileges, the state of
the Ottoman were not to issue Farmans but against the huge amounts of money, and as a
result of that policy got

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Publication Date
Tue Mar 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Laplace Distribution And Probabilistic (bi) In Linear Programming Model
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The theory of probabilistic programming  may be conceived in several different ways. As a method of programming it analyses the implications of probabilistic variations in the parameter space of linear or nonlinear programming model. The generating mechanism of such probabilistic variations in the economic models may be due to incomplete information about changes in demand, pro­duction and technology, specification errors about the econometric relations presumed for different economic agents, uncertainty of various sorts and the consequences of imperfect aggregation or disaggregating of economic variables. In this Research we discuss the probabilistic programming problem when the coefficient bi is random variable

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Crossref
Publication Date
Wed Jun 14 2023
Journal Name
Al-academy
fashion and Contrasting in the contemporary Iraqi theater show
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Since its inception, the theatrical performance has been based on the principle of permanence, continuity, renewal and innovation in the structure of its visual elements. These innovations and the effectiveness of continuity cannot be achieved without searching for everything that is new and different at the level (form and content) in order to create an image with innovative and effective features in the theatrical discourse, and from Among the elements of the theatrical performance (theatrical costumes) that have been subject to variation since the beginning of the theater until now, and for this purpose, the current research was conducted with the question of the research problem: What are the variations of costumes in the contemporar

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Publication Date
Tue Sep 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Separation Benzene and Toluene from BTX using Zeolite 13X
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This work deals with the separation of benzene and toluene from a BTX fraction. The separation was carried out using adsorption by molecular sieve zeolite 13X in a fixed bed. The concentration of benzene and toluene in the influent streams was measured using gas chromatography. The effect of flow rate in the range 0.77 – 2.0 cm3/min on the benzene and toluene extraction from BTX fraction was studied. The flow rate increasing decreases the breakthrough and saturation times. The effect of bed height in the range 31.6 – 63.3 cm on benzene and toluene adsorption from BTX fraction was studied. The increase of bed height increasing increases the break point values. The effect of the concentration of benzene in the range 0.0559 – 0.2625g/

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Publication Date
Wed Mar 16 2022
Journal Name
Journal Of Educational And Psychological Researches
Agreeableness and Its Relation with Orientation towards Voluntary Work
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The current study aims to identify agreeableness and orientation towards voluntary work of officials in public facilities, as well as to identify the nature of the correlation between agreeableness and orientation towards voluntary work of officials in public facilities. To achieve the aims of the research, the researchers designed the agreeableness scale, which consists of (28) items in its final form. The researchers also built a scale of orientation towards voluntary work, which consists of (29) items in its final form. Psychometric properties of validity and reliability of the two scales were extracted in various ways. The researcher applied the two scales on a sample of (400) officials, the results indicated that the

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