In this study, dead and live anaerobic biomass was used in biosorption of Pb(II), Cr(III) and Cd(II) ions from a synthetic wastewater. The biosorption was investigated by batch adsorption experiments. It was found that, the biosorption capacities were significantly affected by biosorbent dosage. The process follows Langmuir isotherm (regression coefficient 0.995, 0.99 and 0.987 for Pb(II), Cr(III) and Cd(II) ions, respectively, onto dead anaerobic biomass) model with uniform distribution over the biomass surface. The experimental uptake capacity was 51.56, 29.2 and 28 mg/g for Pb(II), Cr(III) and Cd(II), respectively, onto dead anaerobic biomass, compared with 35, 13.6 and 11.8 mg/g for Pb(II), Cr(III) and Cd(II), respectively, onto live anaerobic biomass. The percentage reductions of live compared with dead anaerobic biomass in uptake capacity were 32.3, 53.4 and 57.8 for Pb(II), Cr(III) and Cd(II), respectively. The results indicated that, the dead anaerobic biomass is suitable as an efficient biosorbent for the removal of Pb(II), Cr(III) and Cd(II) ions from wastewater.
Objectives. This study was carried out to quantitatively evaluate and compare the sealing ability of Endoflas by using differentobturation techniques. Materials and Methods. After 42 extracted primary maxillary incisors and canines were decoronated, theircanals were instrumented with K files of size ranging from #15 to #50. In accordance with the obturation technique, the sampleswere divided into three experimental groups, namely, group I: endodontic pressure syringe, group II: modified disposable syringe,and group III: reamer technique, and two control groups. Dye extraction method was used for leakage evaluation. Data wereanalyzed using one-way ANOVA and Dunnett’s T3 post hoc tests. The level of significance was set at p<0:05. Results.
... Show MoreLying is considered a dangerous tendency among children if it has become a habit. It results in many social problems, such as child’s loss of confidence, lack of others’ respect to him, and his lack of respect to the desired values of the society, such as honesty and trust. Consequently, he will be led to a deviation when he becomes old; especially if the child’s socially unaccepted behavior has not been directed. The research, thus, aims to examine the causes of lying in the most important stage of children’s life; that is, between (4-6) years. Such an aim helps to know about the individual reasons of lying among males and females from teachers’ perspectives. To meet the objective of the study, a number of (128) children
... Show MoreThe novel is the revelation of the attitudes of every age. And the writers do not know the winner of their stroke to express these events، The research has been working on a descriptive-analytical approach based on the American Comparative School، Al-Shahez's novel explores the work of the nobly and the film by Hamoun by Dariush Mehrjui By relying on the main characters of these two narratives, they depict a picture of Egypt and Iran From the symbolic lines of these works. In fact, the authors of this research have tried to initiate the introduction and analysis of these two works In fact, the authors of this research have tried to initiate the introduction and analysis of these two works.
The results of the research show that
... Show Moremixtures of cyclohexane + n-decane and cyclohexane + 1-pentanol have been measured at 298.15, 308.15, 318.15, and 328.15 K over the whole mole fraction range. From these results, excess molar volumes, VE , have been calculated and fitted to the Flory equations. The VE values are negative and positive over the whole mole fraction range and at all temperatures. The excess refractive indices nE and excess viscosities ?E have been calculated from experimental refractive indices and viscosity measurements at different temperature and fitted to the mixing rules equations and Heric – Coursey equation respectively to predict theoretical refractive indices, we found good agreement between them for binary mixtures in this study. The variation of th
... Show MoreIn this paper ,six new mixed metal ligand complexes are reported with Cephalexin (Ceph.H)as a primary ligand and Dimethylglyoxime (DMG) as secondary ligand with metal Chloride [MCl2 .nH2O. M=Mn(II),Co(II),Cu(II),Ni(II) and Zn(II),n=0-6] ,CrCl3.6H2O.The complexes are of (1:1:1)(Metal:Ligand: Ligand) Stoichiometry.The structures of these complexes are confirmed by using FT-IR and UV- electronic spectroscopies, magnetic moments, melting points, molar conductivity measurements and the metal % analysis revealed that the complexes analyze indicates a four coordinated as (A)=[M(HDMG) (Ceph)] .M=[Ni(II)and Zn(II).Six coordinated as (B) = K2[M(DMG)(CePh)(H2O)]. M= Mn (II),Co(II) and Cu(II) and (C)=[Cr(DMG)(Ceph)]Cl2. Interestingly, the in-vitro anti
... Show MoreIn this paper, the Decomposition method was used to find approximation solutions for a system of linear Fredholm integral equations of the second kind. In this method the solution of a functional equations is considered as the sum of an infinite series usually converging to the solution, and Adomian decomposition method for solving linear and nonlinear integral equations. Finally, numerical examples are prepared to illustrate these considerations.
Two new halogenated azo-Schiff ligands were prepared in two steps. The first step included a condensation between 4-amino acetophenone and 2-fluoro-4-bromo aniline to give the corresponding Schiff base. In the second step, the diazonium salt of this Schiff base reacted with 2-naphthol and 4,5-diphenylimidazole to form two new azo-Schiff base derivatives as ligands; (3-((E)-(4-((E)-1-((4-bromo-2-fluorophenyl) imino)ethyl) phenyl) diazenyl) naphthalen-2-ol (HSBAN) (L1) and ((E)-N-(4-bromo-2-fluorophenyl)-1-(4-((E)-(4,5-diphenyl-1H-imidazol-2-yl)diazenyl) phenyl) ethan-1-imine) (HSBAI) (L2), respectively. These new ligands were characterized by mass spectrometry, FT-IR, 1H NMR, UV-Visible spectroscopy and elemental microanalysi
... Show MoreThis study focused on treatment of real wastewater rejected from leather industry in Al-Nahrawan city in Iraq by Electrocoagulation (EC) process followed by Reverse Osmosis (RO) process. The successive treatment was applied due to high concentration of Cr3+ ions (about 1600 ppm) rejected in wastewater of this industry and for applying EC with moderate power consumption and better results of produced water. In Electrocoagulation process (EC), the effect of NaCl concentration (1.5, 3 g/l), current density (C.D.) (15-25 mA/cm2), electrolysis time (1-2 h), and distance between electrodes (E.D.) (1-2 cm) were examined in a batch cell by implementing Taguchi experimental design. According to the results obtained from multiple regression and signa
... Show MoreThis paper presents studying the performance of three types of polyethersulfone (PES) membrane for the simultaneous removal of Co2+ ions, Cd2+ ions, and Pb2+ ions from binary and ternary aqueous solutions. Co2+ ions, Cd2+ ions, and Pb2+ ions with two different initial concentrations (e.g., 10 and 50 ppm) were selected as examples of heavy metals that contaminate the groundwater as a result of geological and human activities. This study investigated the effect of types of PES membrane and metal ions concentration on the separation process. For the binary aqueous solutions, the permeation flux of the PES2 membranes was higher for the separation process of solutions containing 50 ppm of Cd2+ ions and 10 ppm of Co2+ ions (24.7 L
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