To study the comparative use of some soil minerals (zeolite, bentonite, phosphate rock, and limestone) in the adsorption and release of lead and its removal rates from its aqueous solutions using adsorption equations. Two laboratory experiments were carried out for the adsorption and release of lead. The adsorption experiment took 0.5 g of some of the above soil minerals. Lead was added as Pb (NO3)2 at levels of 3.0, 2.0, 1.5, 1.0, 0.5, and 0.0 mmol L-1 containing a concentration of 0.01M of calcium chloride. The experimental unit’s number was 72, the concentration of dissolved lead in the equilibrium solution was estimated and the amount of lead adsorbed was calculated. As for the lead release experiment, samples for the adsorption experiment were treated after separating filtrates from them with a calcium chloride solution with a concentration of 0.01 M. The amount of lead released was estimated. The percentage of lead removal was calculated. Results showed an increased concentration of dissolved lead in the equilibrium solution directly with increased levels of lead added to all materials. Materials were graded in concentrations of dissolved, adsorbed lead and values of maximum adsorption capacity of lead on different soil minerals surfaces as follows: zeolite > bentonite > phosphate rock > limestone, which reached 5000, 384.61, 769.23, and 2500 mg Pb kg-1, respectively. Binding energy was 0.0062, 0.0056, 0.0019, and 0.0049 L g-1, respectively. The amount of lead released from different adsorption materials varied, with the largest amount released in zeolite amounting to 322.10, 528.20, 696.90, 777.20, and 967.40 mg Pb kg-1 zeolite then bentonite, quantity reached 187.2, 272.8, 314.2, 324.0, and 375.6 mg Pb kg-1 bentonite, then phosphate rock, concentrations reached 65.80, 69.80, 77.60, 91.00, and 123.00 mg Pb kg-1 phosphate rock. Limestone came in fourth and last place in terms of the amount of lead released, concentrations were 25.10, 29.30, 35.00, 38.70, and 40.90 mg Pb L-1 for lead addition treatments of 0.5, 1.0, 1.5, 2.0 and 3.0 mmol L-1, respectively. Soil minerals used varied in their efficiency in removing lead from its aqueous solutions. Zeolite came in first place. Removal rate of lead reached 180.69%, then bentonite 95.47%, phosphate rock 18.48%, and finally limestone 58%.
This paper examines the impact of the organizational culture prevailing at the university center, Ali KafiTindouf, on the quality of the educational service provided by the university center Ali KafiTindouf from the point of view of the teachers of the center. The questionnaire method was used to determine the effect between the variables studied, by the distribution of 33 questionnaires on a random sample of the study community.
The study found that the organizational culture prevailing at the university center of Ali KafiTindouf contributed to reaching higher levels in the awareness and quality of the educational service provided by the teachers of the center.<
... Show MoreThe removal of heavy metal ions from wastewater by sorptive flotation using Amberlite IR120 as a resin, and flotation column, was investigated. A combined two-stage process is proposed as an alternative of the heavy metals removal from aqueous solutions. The first stage is the sorption of heavy metals onto Amberlite IR120 followed by dispersed-air flotation. The sorption of metal ions on the resin, depending on contact time, pH, resin dosage, and initial metal concentration was studied in batch method .Various parameters such as pH, air flow rate, and surfactant concentration were investigated in the flotation stage. Sodium lauryl sulfate (SLS) and Hexadecyltrimethyl ammonium bromide (HTAB) were used as anionic and cationic surfactant re
... Show MoreThis research aims to provide insight into the Spatial Autoregressive Quantile Regression model (SARQR), which is more general than the Spatial Autoregressive model (SAR) and Quantile Regression model (QR) by integrating aspects of both. Since Bayesian approaches may produce reliable estimates of parameter and overcome the problems that standard estimating techniques, hence, in this model (SARQR), they were used to estimate the parameters. Bayesian inference was carried out using Markov Chain Monte Carlo (MCMC) techniques. Several criteria were used in comparison, such as root mean squared error (RMSE), mean absolute percentage error (MAPE), and coefficient of determination (R^2). The application was devoted on dataset of poverty rates acro
... Show MoreThis study aimed at identifying the counseling needs for classroom teachers specialization in
Jerash university. The sample of the study consisted (112) students. To achieve this goal a
scale with (39) items was built by the researcher, this scale has four domains they are as
follows; family, social, psychological and academic domain. The results of this study showed
that counseling needs obtain the heighest average. As well as, the results of the study revealed
that there were statistical differences in favor of gender and teaching year variable. Finally the
study stated a list of recommendations.
The present research deals with the influencing factors which depends on the way perceptual of the graphic designer which enters in the design logos of the loco European health, where the search include four chapters, the researcher reviewed in the chapter 0ne the methodical frame of the research ,as reviewed in the second chapter the theoretical frame, and the previous studies which included three sections, the first section included the perceptual understandable and types of it, and the second section included the influencing factors in the designer perceptual ways and its division . While the third section included the perceptual in graphic designer through the percepted shapes and the relation with ground and colors for express the i
... Show MoreThis study examined the phenomenon of unemployment in Iraq and the extent of the contribution of these loans granted by banks to finance small and medium enterprises in reducing their rates. The temporal boundaries of the study included the period between (2012-2018). The spatial boundaries consisted of random sampling of six Iraqi banks) Where the government banks included (Rafidain, Rasheed and industrial), private banks included (the Iraqi Islamic Bank and the Gulf Commercial Bank and the Bank of the Middle East). In order to achieve the objective of the research in the light of the hypotheses drawn up, the research divided into three topics, the first section highlighting the reality of small and medium enterprises in Iraq and the lo
... Show MoreBackground: Invasion in oral cancer involves alterations in cell-cell and cell-matrix interactions that accompanied by loss of cell adhesion. Catenins stabilize cellular adherence junctions by binding to E-cadherin, which further mediates cell-cell adhesion and regulates proliferation and differentiation of epithelial cells. The Wnt/β-catenin pathway is one of the major signaling pathways in cell proliferation, oncogenesis, and epithelial-mesenchymal transition. Aims of the study: to detect immunohistochemical distribution pattern and different subcellular localization of β-catenin in oral squamous cell carcinoma and relate such expression to Bryne’s invasive grading system. Materials and Methods: This study included 30 paraffi
... Show Moreيعتبر "تاج الأشواك" أو نبات شوكة المسيح، وهو من نباتات الزينة الطبية ، ينتمي إلى جنس يوفوربيا. E. milii يحتوي كميات وفيرة من المركبات الفينولية ، التربينات، الستيرويدات والقلويدات. كانت الأهداف الرئيسية لهذه الدراسة هي فحص مستخلصات الفلافونويد والنانو فلافونويد ضد نوعين من خطوط الخلايا السرطانية. تم تصنيع مركبات الفلافونويد النانوية عن طريق تفاعل مركب الكيتوسان والماليك اسد. تم تحليل مركبات الفلافونويد ال
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