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The effects of the composite flocculant, polyaluminum chloride and poly dimethyldiallylammonium chloride (PACl-PDMDAAC) in comparison with PACl on coagulation efficiencies and membrane fouling in coagulation-ultrafiltration (C-UF) process were analyzed, which was conducted in the conditions of different basicity (B) values and the presence of Mg2+. Results showed that PACl-PDMDAAC enhanced the ability of charge neutralization and absorption bridging, and improved the coagulation efficiency. When B value was 1.5, the flocculant hydrolyzed to form more Alb morphology and effectively removed HA molecules. The presence of Mg2+ could improve the coagulation performance through bridging ability. The results of ultrafiltration test showed that the flux reduction for PACl was 70%, while the flux reduction for PACl-PDMDAAC was 60% in C-UF process. PACl-PDMDAAC could effectively reduce membrane fouling mainly by reducing strongly sttached cake/gel layer. When B value was 1.5, the Alb content of the flocculant was higher and the ability of adsorption charge neutralization was strong, resulting in forming a stable cake layer. Therefore, the membrane fouling was the lightest. In addition, the presence of Mg2+ in raw water reduced the membrane fouling.

This study is intended to identify the social, psychological and physical variables which contribute to kids’ admission to football academies at late childhood phase (values, model, professionalism, sport consciousness, happiness, challenge, ambition, skill, training & education). The sample of this paper is chosen randomly. It comprises 200 parents and 200 kids in late childhood phase. The researcher used the descriptive approach by means of using a questionnaire form for both parents and kids and distributing it randomly on a sample from some sport academies. Statistical means have been used to process data in order to reflect individual differences between average, standard deviation, correlation coefficient, chi-square, & weighted Average. The study has found a correlation with significance between children, parents, mothers, birth place, qualification and some questions to parents with the exception of one question only which doesn’t have any correlation with the five variables (do you see that your son’s practice of football as a profession a means of pride?). By calculating chi-square coefficient, the study has reached the following results: A statistically significant relationship between (children’s age, parents’ age, birth place and qualification) with the following questions: (does father motivate son to join sports academy?) as the value of calculated chi-square is higher than tabular chi-square at significance level of 0.05, and that the value of calculated chi-square for the same question is 59.71 at significance level 0.05 which is higher than tabular value; (does mother motivate her son to join sports academy?) as the value of calculated chi-square is higher than tabular chi-square at significance level 0.05, and that the value of calculated chi-square for the same question was 13.99 at significance level 0.05 which is higher than tabular value; (do you agree that your son practice football as his basic profession?) as the value of calculated chi square is higher than tabular chi2 at significance level 0.05 and that calculated chi-square for the same question was 3.38 at significance level 0.05 as it was 0.066 which is smaller than the tabular value, however, it is accepted at significance level 0.10 and, (Are you a member at the club of the academy?) as the value of calculated chi-square is higher than tabular chi-square at significance level 0,05 and that the value of calculated chi-square for the same question was 38.72 at significance level 0.05 which is higher than tabular value. Calculating the chi-square coefficient, the study comes to the following: there is a correlation between birth location and qualification, since difference of governorate and birth location creates differences between governorates, as each governorate has its own habits and beliefs. The previous frequency tables exposes that Cairo and Giza are on top of governorates including football academies. Regarding qualification, the post-graduate educated parents ratio reaches 25% of the sample, while the university-educated parents represents 60% and the middle-educated parents is 155 and they are all totally aware of the necessity to encourage their children to learn football, seeking money and fame from that, being professionals and travelling abroad which is finally better than education. Lights, fame, players’ news, and their selling prices have become more important than a child’s learning of writing and reading, benefitting from the internet or reading scientific stories. The most interesting, is that parents have no objection to that, and they don’t object it to become their kids’ main job. Results also indicate that the probable mean for fathers’ encouraging their children reaches 96.33% while mothers’ ratio is 72.67% and that convenience level of children practicing soccer as a main career is 75.33 for both sexes. These results show that children are increasingly joining soccer academies and parents are seeking to train them to be under supervision of stars of football which makes it easy to become professional.

Ultra-filtration technology has been increasingly used in drinking water treatment due to improvements in membrane performance and lowering of costs. However, membrane fouling is the main limitation in the application of ultra-filtration technology. In this study, we investigated the impact of four different pre-treatments: Coagulation, adsorption, coagulation followed by adsorption (C-A), and simultaneous coagulation and adsorption (C+A), on membrane fouling and natural organic matter removal efficiency. The results showed that adsorption process required a large amount of adsorbent and formed a dense cake layer on the membrane surface leading to severe membrane fouling. Compared to adsorption alone, the coagulation and C-A processes decreased the transmembrane pressure by 4.9 kPa. It was due to less accumulation of particles on the membrane surface. As for water quality, the C-A ultra-filtration process achieved the highest removal efficiencies of natural organic matter and disinfection by-product precursors. Therefore, the addition of adsorbent after coagulation is a potentially important approach for alleviating ultra-filtration membrane fouling and enhancing treatment performance.

In order to investigate the characteristics of pure Nano-Al13, Nano-Al13 was separated and purified from a series of poly-aluminum chloride (PAC) solutions which had the same Al13 percentage but different total Al concentrations, by using column chromatography, ethanol-acetone resolving and SO2− 4/Ba2+ displacement. The Al13 species yield was characterized by Al-ferron timed complexation spectrophotometry and 27Al-NMR (nuclear magnetic resonance). The coagulation efficiency of Nano-Al13, PAC and AlCl3 in synthetic water was also investigated by Jar tests. The dynamic process and aggregation state of kaolin suspensions coagulating with Nano-Al13, PAC and AlCl3 were similarly investigated using a photometric dispersion analyzer 2000 (PDA2000). The experimental results indicated that the ethanol-acetone resolving method was simple and could separate the PAC solution at different concentrations, while column chromatography could separate PAC solutions at low concentrations. The SO4 2−/Ba2+ displacement method could separate PAC solutions at high concentrations. However, extra inorganic cation and anion could be added in the solution during separation. The coagulation efficiency and dynamic experimental results showed that Nano-Al13 with high positive-charged species was effective in removing turbidity and color. The dynamic process results showed that Nano-Al13 also had the best recovery capability after shearing compared with PAC and AlCl3 because the Nano-Al13 conformation is more effective in charge neutralization.

Carbon nanotubes (CNTs) were used as adsorbent to remove fulvic acids (FA) from aqueous solutions. The adsorption capacity of CNTs for FA can reach 24 mg g−1 at 5 °C and equilibrium concentration of 18 mg dm−3. The kinetic and thermodynamic parameters, such as rate of adsorption, standard free energy changes (ΔG0), standard enthalpy change (ΔH0) and standard entropy change (ΔS0), have been obtained. Acidic conditions (pH = 2–5) favor FA removal. An increase in the ionic strength or the addition of divalent cations increase the adsorption of FA dramatically (FA = 60 mg dm−3). An increase in the maximum adsorbed amount of FA was observed when treating FA in synthetic seawater. Desorption studies reveal that FA can be easily and quickly removed from CNTs by altering the pH values of the solution. Good adsorption capacity and quick desorption indicate that CNTs are a promising adsorbent to remove FA from aqueous solutions. Copyright © 2007 Society of Chemical Industry

The median temperature sulfur fixation characteristics in flue gas of experimental wastes were studied by Tube Furnace, the phase composition and mineral content of sulfur fixation product were analyzed by XRD and thermal gravimetric, median-temperature sulfur fixation mechanism of alkali industrial waste were discussed, which provide theoretical basis for preparation of waste type median-temperature sulfur fixation agents. It can be found that some experiments alkali industrial waste such as: alkali slag, red mud and salt slurry have better sulfur fixation characteristics because of rich in Al2O3, Fe2O3 and SiO2, and so on, On the one hand, Al2O3, SiO2 and Fe2O3 make initial grain size of carbonate crystallization small and dispersion high, which can increase surface area of sulfur fixation reaction, thin product thickness, reduce diffusion resistance of product layer and raise the proportion of carbonate forming sulfate, on the other hand, Al2O3, SiO2 and Fe2O3 play the role of transferring oxygen during the formation process of CaSO4, which result in CaSO3 is easily oxidized and form sulfate calcium.

The adsorption of humic acid (HA) on kaolin particles was studied at various conditions of initial solution pH, ionic strength and solid-to-liquid ratio. The resulting affinity of interactions between humic acid and kaolin was attributed to the surface coordination of HA in ambient suspensions of mineral particles and the strong electrostatic force at low pH. Addition of inorganic salt can also influence the adsorption behavior by affecting the HA molecular structure, the clay particle zeta potential and so on. Equilibrium data were well fitted by the Freundlich model and implied the occurrence of multilayer adsorption in the process. In addition, the enthalpy dependent of system temperature was 79.17 kJ/mol, which proved that the mechanism of HA adsorption onto kaolin was comprehensive, including electrostatic attraction, ligand complexation and hydrogen bonding.