The present work reports the performance of three types of polyethersulfone (PES) membrane in the removal of highly polluting and toxic lead Pb2+ and cadmium Cd2+ ions from a single salt. This study investigated the effect of operating variables, including pH, types of PES membrane, and feed concentration, on the separation process. The transport parameters and mass transfer coefficient (k) of the membranes were estimated using the combined film theory-solution-diffusion (CFSD), combined film theory-Spiegler-Kedem (CFSK), and combined film theory-finely-porous (CFFP) membrane transport models. Various parameters were used to estimate the enrichment factors, concentration polarization modulus, and Péclet number. The pH values significantly affected the permeation flux of the Pb2+ solution but only had a slight effect on the Cd2+ solution. However, Cd2+ rejection was highly improved by increasing the pH value. The rejection of the PES membranes increased greatly as the heavy metal concentration rose, while the heavy metal concentration moderately affected the permeation flux. The maximum rejection of Pb2+ in a single-salt solution was 99%, 97.5%, and 98% for a feed solution containing 10 mg Pb/L at pH 6, 6.2, and 5.7, for PES1, PES2, and PES3, respectively. The maximum rejection of Cd2+ in single-salt solutions was 78%, 50.2%, and 44% for a feed solution containing 10 mg Cd/L at pH 6.5, 6.2, and 6.5, for PES1, PES2, and PES3, respectively. The analysis of the experimental data using the CFSD, CFSK, and CFFP models showed a good agreement between the theoretical and experimental results. The effective membrane thickness and active skin layer thickness were evaluated using the CFFP model, indicating that the Péclet number is important for determining the mechanism of separation by diffusion.
Mortar of ordinary Portland cement was blended with cockles shell
powder at different weight ratios to investigate the effect of powder
admixture on their strength and thermal conductivity. Results showed
that addition of cockles shell powder at 50% of mortar weight
improves hardness and compressive strength notably and reduces the
thermal conductivity of the end product. Results suggest the
possibility to incorporate cockles shell powders as constituents in
cement mortars for construction and plastering applications.
The junction between polythiophene, a conducting polymer formed by electrochemical polymerization, and n-type silicon was studied the temperature and doping dependencies were observed in the junction characteristics. The increase of junction temperature leads to increase the saturation current, the barrier height, and decrease of the ideality factor for junction. While the reduction in doping concentration causes a decrease in the forward current. The results were explained according to the conventional Schottky diode theories.
Praise be to Allaah Mahmoud every tongue, the idol of all time, which is not without
his knowledge everywhere, not occupied like for like, most of all likes and peer, and picnic
for wife and children, and carried out his reign in all the subjects, neither representative by the
brains to think, nor fancy hearts photography, (is not nothing like Him, He is the All-Seer),
and prayer and peace be upon the Messengers Muhammad and his family and companions
and followed them in truth until the Day of Judgment.
After…..
Has spoken in this search for The inheritance of women before and after Islam
legislative provisions which, because of its importance to show the right of women's rights,
which began Msluba before Isl
Background: Accurate detection of thyroid autoantibodies by enzyme linked immunosorbant assay technique namely thyroglobulin antibody, thyroid peroxides antibody is crucial in the differentiation of autoimmune thyroid disorders from other form of thyroid diseases.
Objective: Evaluation of the detection of thyroglobulin antibody and thyroid peroxides antibody in different thyroid diseases using enzyme linked immunosorbant assay technique.
Methods: - Seventy-five patients admitted to Surgical Units of Baghdad Medical City Hospital for the period between "October 2010 to June 2011" they were waiting to do thyroidectomy. They were chosen nonselectively for serological evaluation of above autoantibodies , and correlation of the results
In the present paper, the concepts of a quasi-metric space, quasi-Banach space
have been introduced. We prove some facts which are defined on these spaces and
define some polynomials on quasi-Banach spaces and studied their dynamics, such
as, quasi cyclic and quasi hypercyclic. We show the existence of quasi chaotic in the
sense of Devaney (quasi D-chaotic) polynomials on quasi Banach space of qsummable
sequences lq , 0<q<1 such polynomials P is defined by P((xi)i)=(p(xi+m))i
where p:CC, p(0) = 0. In general we also prove that P is quasi chaotic in the sense
of Auslander and Yorke (quasi AY-chaotic) if and only if 0 belong to the Julia set of
p, mN. And then we prove that if the above polynomial P o
A dynamical system describes the consequence of the current state of an event or particle in future. The models expressed by functions in the dynamical systems are more often deterministic, but these functions might also be stochastic in some cases. The prediction of the system's behavior in future is studied with the analytical solution of the implicit relations (Differential, Difference equations) and simulations. A discrete-time first order system of equations with quadratic nonlinearity is considered for study in this work. Classical approach of stability analysis using Jury's condition is employed to analyze the system's stability. The chaotic nature of the dynamical system is illustrated by the bifurcation theory. The enhancement o
... Show MoreThe anatomical study showed the epidermis leaves of Ricinus communis L.glabrous and withparacytic pattern, also the midrib of leavescomposedfrom a pyramidal shapearea with a circular tip like ascamel humpfrom the upper side consisting of supported collenchyma tissue, and the cross section of leaf petiole formed as an ovate shape as for the cross section of stem was a circular, also observed many druces crystaland aleuron grains that are spread in the cortex area. Pollen grain appeared under a scanning electron microscope that tricolporate, either the surface pattern was reticulate and the shape of pollen grain prolate spheroidal to subprolate
This research presents a study in ultra-desulfurization of diesel fuel produced from conventional hydro desulfurization process, using oxidation and solvent extraction techniques. Dibenzothiophene (DBT) was the organosulfur compound that had been detected in sulfur removal. The oxidation process used hydrogen peroxide as an oxidant and acetic acid as homogeneous catalyst . The solvent extraction process used acetonitrile (ACN) and N-methyl – 2 - pyrrolidone (NMP) as extractants . Also the effect of five parameters (stirring speed :150 , 250 , 350 , and 450) rpm, temperature (30 , 40 , 45 , and 50) oC, oxidant/simulated diesel fuel ratio (0.5 , 0.75 , 1 , and 1.5) , catalyst/oxidant ratio(0.125,0.25,0.5
... Show MoreWords worth and the Intention of AL. Sayyab Discourse
Playing is the only common language among children in every place and time, to the fact that what distinguishes the children is their quest to play and fun way innate, not acquired, which is expressed with the child really is one of the rights. And play a key entrance to the growth of the child mentally, intellectually and cognitively and not for the child emotionally and socially just. In the play the child begins to identify and classify objects and learn concepts and circulate among themselves on a linguistic basis. Activity here and play a major role in leading the linguistic development of the child in the composition has the communication skills.
The Games (especially intellectual ones) Whatever the cause of the development
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