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%.
Coronavirus disease (Covid-19) has threatened human life, so it has become necessary to study this disease from many aspects. This study aims to identify the nature of the effect of interdependence between these countries and the impact of each other on each other by designating these countries as heads for the proposed graph and measuring the distance between them using the ultrametric spanning tree. In this paper, a network of countries in the Middle East is described using the tools of graph theory.
The villa was incredible, summer was hot, and the Mediterranean Sea was so near.
Scil lived happily with her father as they needed no one else. But the visit of a calm and intelligent women caused huge shift in this delightful mess. So, how can this threat be stopped?
This novel displays to the reader a rich study of human soul to implicitly while being supported by short sentences and characterised by persons living in a horrible way and described in very short sentences.Thus, Françoise Sagan’s imagination was enflamed, and so he shaped ethical imagery in the moste wonderful way in the novel Hi, Sadness.
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... Show MoreThe utilization of targeted therapy for programmed death ligand 1 (PD‑L1) has emerged as a prominent focus in contemporary clinical trials, particularly in the context of immune checkpoint inhibitors. The prognostic significance of the expression of PD‑L1 in invasive mammary cancer remains a subject of discussion in clinical oncology, requiring further exploration, despite its recognition as a biomarker for responsiveness to anti‑PDL1 immunotherapy. The present study was conducted to investigate the immunohistological expression of PD‑L1 in women with triple‑negative breast cancer (TNBC), with a particular focus for searching for the associated clinical and pathological characteristics. The present retrospective study examined the
... Show MoreThe present paper addresses cultivation of Chlorella vulgaris microalgae using airlift photobioreactor that sparged with 5% CO 2 /air. The experimental data were compared with that obtained from bioreactor aerated with air and unsparged bioreactor. The results showed that the concentration of biomass is 0.36 g l -1 in sparged bioreactor with CO2/air, while, the concentration of biomass reached to 0.069 g l -1 in the unsparged bioreactor. They showed also that aerated ioreactor.with CO2/air gives more biomass production even the bioreactor was aerated with air. This study proved that application of sparging system for ultivation of Chlorella vulgaris microalgae using either CO2/air mixture or air has a significant
... Show MoreChilled ceilings systems offer potential for overall capital savings. The main aim of the present research is to investigate the thermal performance of the indirect contact closed circuit cooling tower, ICCCCT used with chilled ceiling, to gain a deeper knowledge in this important field of engineering which has been traditionally used in various industrial & HVAC systems. To achieve this study, experimental work were implemented for the ICCCCT use with chilled ceiling. In this study the thermal performances of closed wet cooling tower use with chilled ceiling is experimentally and theoretically investigated. Different experimental tests were conducted by varying the controlling parameters to investigate their effects
... Show MoreMany isolated rural communities are located in regions where there is an abundant and reliable supply of solar energy, but where the distance to the nearest power station is many tens or even hundreds of kilometre. It is therefore mainly in these areas that rural electrification is now being provided by PV generators. since Stand-Alone PV generator can offer the most cost-effective and reliable option for providing power needed in remote places. Accordingly these isolated rural canters are fitted with PV for lighting, a refrigerator, a television and socket to supply kitchen appliances
Covariance technique represents a design to bring out the decorative components And organized in unfamiliar a manner Turn to custom patterned to make a qualitative difference in the pattern of the general composition of the implicit overall,question research problem emerges Based on the above, (Is the aesthetic values of the property heterogeneities in Islamic architecture configurations decorations?). Detect it through the knowledge of the species and decorative components containing heterogeneities And his methods within each of Iraq and Iran and theoretical framework try to monitor the opinions and threads aesthetic perception in the Islamic and Construction decorative art formations in Islamic architecture and features of heterogenei
... Show MoreObjectives: To determine Smartphone addiction among primary school students and its impacts. The samples of the study were240primary school students in derived from stratified random sampling. The questionnaire was used to collect the data. The data were then an- analyzed using correlation statistics. It also caused a negative impact on demic performance of the primary school students.
Methodology: A cross- sectional study in assessment approach in applied in order to achieve the earlier stated objectives. The study was initiated from October 1st, 2019 to April 30th, 2020. Simple random sampling (probability) sample of (240) Pupils study In primary school at Al-Rusafa first directorate schools in Baghdad City.
Results: The study re
The effective insulation design of the stress grading (SG) system in form-wound stator coils is essential for preventing partial discharges and excessive heat generation under pulse-width modulation excitation. This paper proposes a method to find the optimal insulation design of the SG system aimed at reducing the dielectric and thermal stresses in the machine coil. The non-uniform transmission line model is used to predict the voltage propagation along the overhang, SG, and slot regions considering the variation in the physical properties of the insulation layers. The machine coil parameters for different insulation materials are calculated by using the finite element method. Two optimization algorithms, fmincon and particle swarm optimiz
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