Anodic electrodeposition was used to synthesize a composite electrode of nanostructured manganese dioxide/carbon fiber (CF) galvanostatically. Different characterization results of the nanostructured MnO2 were obtained by varying the H2SO4 concentration and the current density. Field emission scanning electron microscopy, X‐ray diffraction, and atomic force microscopy were utilized to characterize the prepared composite electrodes. The best conditions were: 0.3 mA cm−2 current density and 0.64 M H2SO4 concentration. The electrosorption performance of the MnO2/CF electrode prepared under the best conditions was tested by way of its chromium(VI) ion adsorption from a simulated solution. The applied voltage, pH, and ionic strength affect the efficiency of Cr(VI) ion removal. The highest chromium removal efficiency was 99.98 %, achieved at pH 2, a cell voltage of 4.6 V, and a NaCl concentration of 1 g L−1.
Abstract:
The aim of this research to try to determine the type of expected relationship between inflation as the explanatory variable and market performance as a dependent variable, for that used data issued and published by the Central Bank of Iraq and the Iraqi Stock Exchange for a sample consisting of (159) observations using the intentional or intentional sampling method for the period extending between the months (January 2010 to March 2023), in the light of each of the Consumer Price Index (CPI), the Iraqi Stock Exchange Index, the number of traded shares and the number of market capital shares to ex
... Show MoreCoupling reaction of 2-amino benzoic acid with the 8-hydroxy quinoline gave the azo ligand (H2L): 5-(2-benzoic acid azo )-8-hydroxy quinoline.Treatment of this ligand with some metal ions (CoII, NiII and CuII ) in ethanolic medium with a (1:2) (M:L) ratio yielded a series of neutral complexes with general Formula[M(HL)2],where: M=Co(II), Ni(II) and Cu(II), HL=anion azo ligand (-1).The prepared complexes were characterized using flame atomic absorption,FT-IR and UV-Vis spectroscopic methods as well as magnetic susceptibility and conductivity measurements.
The formation of Co(II), Ni(II), Cu(II), Zn(II), and Cd(II)-complexes (C1-C5) respectively was studied with new Schiff base ligand [benzyl(2-hydroxy-1-naphthalidene) hydrazine carbodithioate derived from reaction of 2-hydroxy-1-naphthaldehyde and benzyl hydrazine carbodithioate. The suggested structures of the ligand and its complexes have been determined by using C.H.N.S analyzer, thermal analysis, FT-IR, U.V-Visible, 1HNMR, 13CNMR , conductivity measurement , magnetic susceptibility and atomic absorption. According to these studies, the ligand coordinates as a tridentate with metal ions through nitrogen atom of azomethane , oxygen atom of hydroxyl, and sulfur atom of thione
... Show MoreA new chelate complexes of Co(II),Ni(II),Zn(II) and Cd(II) were prepared by reacting these ions with the ligand 2-[4- Carboxy methyl phenyl azo]-4,5-diphenyl imidazole (4CMeI) The preparation were conducted after fixing the optimum conditions such as (pH) and concentration .UV- visible spectra of these complex solutions were studied for a range of (pH) and concentration which obey lampert-Beers Law.The structures of complexes were deduced according to mole ratio method which were obtained from the spectroscopic studies of the complex solutions .The ratios of metal: ligand obtained were (1:2) for all complexes..(UV-Vis) absorption spectra and The infrared spectra of the chelating complexes were studied ,this may indicate that coordination be
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Abstract
This study aims to identify the degree to which the first cycle teachers use different feedback patterns in the e-learning system in addition to the differences in the degree of use according to specialization, teaching experience, and in-service training in the field of classroom assessment, as well as the interaction between them. The study sample consisted of (350) female teachers of the first cycle in government schools in Muscat Governorate for the academic year 2020/2021. The study used a questionnaire that contained four different patterns of feedback, which are reinforcement, informative, corrective, and interpretive feedback. The psychometric properties of the que
... Show MoreSelect the researcher discussed problem of asking the following : Do you use visual intelligence strategy effective in the collection of students in the Department of Art Education in the foreseeable material ? The research aims to " measure the effectiveness of the strategy in the collection of visual intelligence students in the Department of Art Education in the foreseeable material ". To verify the objective of this research was identify hypotheses zero to measure the level of achievement in the foreseeable material second grade students in the Department of Art Education - Faculty of Fine Arts . The population of the research students in the Department of Art Education / Faculty of Fine Arts at the University of Baghdad who are stud
... Show MoreThe goal of this research to identify the effect of the probing questions in the collection of material literature with students of the Kurdish language department, to achieve the aim of the research, the researcher has chosen a sample from the students of third stage of the Kurdish language Department, Faculty of Education / Ibn Rushd as a field for the application of experiment.The number of sample reached (71) students divided into two groups represented two divisions of the experimental groups under study to the style of questions sounding by (35) students, and represented the other division of the control group, which studied in the way normal and by (36) students, as rewarded r
... Show MoreThis study aims to recognize the process of using computer in publicschools in Ma`an governorate in terms of hardware, capabilities, and teachers usage. It also aims to identify the most important obstacles those schools face from a teachers perspective.
The study sample consists of (150) teachers from different disciplines. The researcher prepared two questionnaires related to the research pivotal, then presented to a group of arbitrators to be used in this final form. The data was analyzed statistically and the study concluded that there is a shortage in the computer services provided to teachers, and there is a w
... Show MoreAbstract:
This tribe had lived in Iraq since the first century A.D. Persia tried to
keep this tribe away from Iraq, but without result. The tribe managed to get
victory against Persia in the battle of Dhyqar.
When the Muslims had come to conquer Iraq, Rabi’a welcomed them
and takes part in that action.
That tribe helped the caliph Ali in the Jammal and Sifffen wars in order
to remain Iraq the center of the Islamic caliphates this tribe had felt very sad
and sorrowful when the caliphate become to the Umayyad . This tribe did not
give up, so this tribe did what could be done to help those who had revolted
against the Umayyad. Rabi’a did that in order to get ride of the Mudriat alsham,
and favored Rabi
Suspicion in the truth that the satisfaction of the student in the criticism of the speech of the poet and the writer to I bin Al-Atheer