doi:10.21123/bsj.2010.7.1.745-756

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Publication Date

Sun Mar 07 2010

Journal Name

Baghdad Science Journal

Volume

7

Issue Number

1

DOI

10.21123/bsj.2010.7.1.745-756

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Adsorption Study for Chromium (VI) on Iraqi Bentonite

"Study

Adsorption

Chromium

Bentonite."

Khulood A.

Sara Badrie

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The subject of this research involves studying adsorption to remove hexavalent chromium Cr(VI) from aqueous solutions. Adsorption process on bentonite clay as adsorbent was used in the Cr(VI) concentration range (10-100) ppm at different temperatures (298, 303, 308 and 313)K, for different periods of time. The adsorption isotherms were obtained by obeying Langmuir and Freundlich adsorption isotherm with R2 (0.9921-0.9060) and (0.994-0.9998), respectively. The thermodynamic parameters were calculated by using the adsorption process at four different temperatures the values of ?H, ?G and ?S was [(+6.582 ? +6.547) kJ.mol-1, (-284.560 ? -343.070) kJ.mol-1 and (+0.977 ? +1.117) kJ.K-1.mol-1] respectively. This data indicates the spontaneous sorption process. The kinetic study of adsorption process was studied depending on three kinetic equations: 1- Lagergren equation 2- Morris-Weber equation 3- Reichenberg equation

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Publication Date

Sun Sep 01 2013

Journal Name

Baghdad Science Journal

Six-coordinate oxime-imine cobalt(III) complexes with amino acid co-ligands; synthesis and characterisation

Schiff-base imine-oxime ligands

diaminoethane-N

N`-bis(2-butylidine-3-onedioxime) H2L1 and o-pheneyenediamine-N.N-bis(2-butylidine-3-onedioxime) H2L2

Six coordinate Co(III)-complexes

Structural study.

Mohamad J.

Hasan A.

Alaa M.

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In this publication, several six coordinate Co(III)-complexes are reported. The reaction of 2,3-butanedione monoxime with ethylenediamine or o-phenylenediamine in mole ratios of 2:1 gave the tetradentate imine-oxime ligands diaminoethane-N,N`-bis(2-butylidine-3-onedioxime) H2L1 and o-phenylenediamine-N,N`-bis(2-butylidine-3-onedioxime), respectively. The reaction of H2L1 and H2L2 with Co(NO3)2, and the amino acid co-ligands (glycine or serine) resulted in the formation of the required complexes. Upon complex formation, the ligands behave as a neutral tetradantate species, while the amino acid co-ligand acts as a monobasic species. The mode of bonding and overall geometry of the complexes were determined through physico-chemical and spectro

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Publication Date

Tue Oct 20 2020

Journal Name

Ibn Al-haitham Journal For Pure And Applied Sciences

Fuzzy Semimaximal Submodules

Let R be a commutative ring with unity and an R-submodule N is called semimaximal if and only if Mâ„(Nis a semisimple R-module ).The main objective of this work is to fuzzify this concept

study the basic properties and we investigate the sufficient conditions of F-submodules to be semimaximal .Also the concepts of (simple

semisimple) F- submodules and quotient F- modules are introduced and given some properties .

Maysoun

Hatam

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Let R be a commutative ring with unity and an R-submodule N is called semimaximal if and only if

the sufficient conditions of F-submodules to be semimaximal .Also the concepts of (simple , semisimple) F- submodules and quotient F- modules are introduced and given some properties .

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Publication Date

Mon Nov 01 2010

Journal Name

Al-nahrain Journal Of Science

Chemical Elements Diffusion in the Solar Interior

The standard solar model and equation of state have been used to study relative diffusion of Hydrogen and Helium in the present time for solar interior

as a function of distance and depth from the center of the star. The effects of temperature and density on diffusion velocity for these chemical elements have been explaned. It is found that heat flow which is arising from these reactions leads to an increase in helium diffusion velocity

while the temperature and density leading to a decrease in Hydrogen diffusion velocity. This means that Hydrogen behaves inversely with that for helium does through these reactions. Accordingly

diffusion percentages for Hydrogen

Helium and other Heavy Elements could be determined for the main sequence stars and white dwarf stars.

H.

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Publication Date

Fri Mar 01 2019

Journal Name

Applied Acoustics

Theoretical model of absorption coefficient of an inhomogeneous MPP absorber with multi-cavity depths

Micro-perforated panel (MPP) absorber has been known as an alternative absorber to classical porous material given its facile installation

long durability

environmental friendliness and attractive appearance. Extensive studies of MPP absorber proposing the improvement of its absorption frequency bandwidth have been published. This study presents a MPP absorber introduced with inhomogeneous perforations and with multi-cavity depths. The MPP is divided into two sub-area

where each area has different hole diameter

perforation ratio and a separated backed cavity depth. The acoustic impedance is modelled using electrical equivalent circuit and the absorption coefficient is calculated under normal-incidence of sound. It is found that the inhomogeneous MPP can have good bandwidth of absorption by designing the sub-MPP of smaller perforation ratio with large hole diameter and the one having the larger perforation ratio with smaller hole diameter. The absorption bandwidth can be conveniently controlled by adjusting the cavity depth of each sub-MPP. The results from the experimental work show good agreement with the theoretical model.

Ali Ibrahim

Azma

Roszaidi

Iwan

Al-Ameri

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Publication Date

Tue Apr 01 2014

Journal Name

Journal Of Economics And Administrative Sciences

Financial markets liquidity and their impact in the return of common stocks

The research aimed to study the financial markets liquidity and returns of common stocks

Take the research the theoretical concepts associated with each of the liquidity of financial markets and returns of common stocks

As well as the use of mathematical methods in the practical side to measure market liquidity and Stocks Return

the community of research in listed companies in Iraqi stock exchange that have been trading on its stock and number 85 joint-stock company

The research was based to one premise

there is a statistically significant effect for the liquidity of the Iraqi stock exchange on returns of common stocks to traded companies in which

Using the SPSS program was to test the hypothesis research population represented Iraq Stock Exchange for a period of three years (2010-2012) on a monthly basis. The research found the set of conclusions most important rising market liquidity for Iraq Stock Exchange and followed increase in return of common stocks for a period of research

as the results of statistical analysis indicated the presence of a statistically significant effect of moral Iraq Stock Exchange liquidity on returns of common stocks

and most important recommendations should the Iraq Stock Exchange work to expand its activities in electronic trading

by providing the possibility of trading for investors through the Internet

and not limited to trading within the market

and should work to reduce the transaction costs to raise the liquidity common stock

and thus reflect positively on the liquidity of the Iraq Stock Exchange brokerage firms associated with it .

اياد طاهر

محمد حمدان

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The research aimed to study the financial markets liquidity and returns of common stocks , Take the research the theoretical concepts associated with each of the liquidity of financial markets and returns of common stocks , As well as the use of mathematical methods in the practical side to measure market liquidity and Stocks Return, the community of research in listed companies in Iraqi stock exchange that have been trading on its stock and number 85 joint-stock company, The research was based to one premise, there is a statistically significant effect for the liquidity of the Iraqi stock exchange on returns of common stocks to traded companies in which , Using th

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Publication Date

Sat Oct 01 2016

Journal Name

Journal Of Theoretical And Applied Information Technology

Factors affecting global virtual teams’ performance in software projects

Today the trend is to perform software development work via distributed geographical area among team

individual or even as an organization. However

due to the global market and international presence of many companies

there is a need to implement a global virtual teams. The global virtual team members are gradually engaged in globalized business environments across space

time and organizational boundaries via information and communication technologies. A global virtual team relies on communication

collaboration

and information exchange are the most important criteria in global virtual teams’ operations. The purpose of this paper is to answer two research questions. The first research question is to identify the factors affecting global virtual teams’ performance. A systematic literature review was conducted to answer the first research question. The second research question is on what the rank of the factor affecting the global virtual teams’ performance according to their level of effect on global virtual teams’ performance. Online survey was conducted within 103 developers and IT managers from eight IT companies to answer the second research question. The Statistical Package for Social Science (SPSS 22) was used to analyze the collected data. In this study

we investigated factors that affect global virtual teams’ performance

factors considered include cultural differences

language problems

time-zone differences

team size

technical problems

lack of trust

lack of sufficient training

and ICT problems. Also the findings indicated that lack of sufficient training is the highest level of effect on global virtual teams’ performance. On the other hand

Ali Yahya Gheni

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