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 research was carried out to study the effect of plants on the wetted area for two soil types in Iraq and predict an equation to determine the wetted radius and depth for two different soil types cultivated with different types of plants, the wetting patterns for the soils were predicted at every thirty minute for a total irrigation time equal to 3 hr. Five defferent discharges of emitter and five initial volumetric soil moisture contents were used ranged between field capacity and wilting point were utilized to simulate the wetting patterns. The simulation of the water flow from a single point emitter was completed by utilized HYDRUS-2D/3D software, version 2.05. Two methods were used in developing equations to predict the domains o
... Show MoreWater produced from power plants is one of the most important sources of water pollution, especially for areas like Baghdad, Contaminated industrial wastewater is a major environmental challenge due to the rapid growth of industries, leading to increased accumulation of harmful pollutants in water resources, the work is intended to study the impact of water generated from a power plant in the south on the level of heavy metals before and after the treatment process and after its discharge to the Tigris River. Objective is to determine the extent of heavy metals such as iron, copper, chromium, and zinc concentration in water extracted from various points and subsequently study the monthly variations of these elements with a view to assessmen
... Show MoreThe research dealt with a comparative study between some semi-parametric estimation methods to the Partial linear Single Index Model using simulation. There are two approaches to model estimation two-stage procedure and MADE to estimate this model. Simulations were used to study the finite sample performance of estimating methods based on different Single Index models, error variances, and different sample sizes , and the mean average squared errors were used as a comparison criterion between the methods were used. The results showed a preference for the two-stage procedure depending on all the cases that were used
This growing interest of the international scientific specialized commissions is due to the role that the audit committee can play, as one of companies’ governance tools, to increase the accuracy and transparency of the financial information disclosed by the companies, through its oversight role on the process of preparing financial reports, its supervision on the internal audit function within the companies, and supporting its independency, as well as coordinating the efforts between the internal control unites and the external auditor represented by the (Board of Supreme Audit) to clear the observations and irregularities in order to reduce the fraud cases.
This research was built on an applied sample of audit committee works
... Show MoreA mixture model is used to model data that come from more than one component. In recent years, it became an effective tool in drawing inferences about the complex data that we might come across in real life. Moreover, it can represent a tremendous confirmatory tool in classification observations based on similarities amongst them. In this paper, several mixture regression-based methods were conducted under the assumption that the data come from a finite number of components. A comparison of these methods has been made according to their results in estimating component parameters. Also, observation membership has been inferred and assessed for these methods. The results showed that the flexible mixture model outperformed the
... Show MoreA mixture model is used to model data that come from more than one component. In recent years, it became an effective tool in drawing inferences about the complex data that we might come across in real life. Moreover, it can represent a tremendous confirmatory tool in classification observations based on similarities amongst them. In this paper, several mixture regression-based methods were conducted under the assumption that the data come from a finite number of components. A comparison of these methods has been made according to their results in estimating component parameters. Also, observation membership has been inferred and assessed for these methods. The results showed that the flexible mixture model outperformed the others
... Show MoreA new ligand (H4L) and its complexes with ( ZnII, CdII and HgII) were prepared. This ligand was prepared in two steps. In the first step a solution of terephthaldehyde in methanol was reacted under reflux with 1,2-phenylenediamine to give an precursor compound which reacted in the second step with 2,4-dihydroxybenzaldehyde to give the ligand. The complexes were then synthesized by direct reaction of the corresponding metal chloride with the ligand. The ligand and complexes were characterized by spectroscopic methods FT-IR, UV-Vis, 1 HNMR, and atomic absorption, chloride content, HPLC, mole-ratio determination. in addition to conductivity measurement. The data of these measurements suggest a distorted tetrahedral geometry for ZnII, C
... Show MoreAnalysis the economic and financial phenomena and other requires to build the appropriate model, which represents the causal relations between factors. The operation building of the model depends on Imaging conditions and factors surrounding an in mathematical formula and the Researchers target to build that formula appropriately. Classical linear regression models are an important statistical tool, but used in a limited way, where is assumed that the relationship between the variables illustrations and response variables identifiable. To expand the representation of relationships between variables that represent the phenomenon under discussion we used Varying Coefficient Models
... Show MoreRutting has a significant impact on the pavements' performance. Rutting depth is often used as a parameter to assess the quality of pavements. The Asphalt Institute (AI) design method prescribes a maximum allowable rutting depth of 13mm, whereas the AASHTO design method stipulates a critical serviceability index of 2.5 which is equivalent to an average rutting depth of 15mm. In this research, static and repeated compression tests were performed to evaluate the permanent strain based on (1) the relationship between mix properties (asphalt content and type), and (2) testing temperature. The results indicated that the accumulated plastic strain was higher during the repeated load test than that during the static load tests. Notably, temperatur
... Show MoreCarbamazepine is an anticonvulsant agent which acts on the central nervous system and used for the treatment of epilepsy. Carbamazepine was formulated as an oral extended release tablets using ethyl cellulose as retardant substance. Different types of tablets additives such as cellulose materials (sodium carboxymethyl cellulose and microcrystalline cellulose ), lactose, calcium phosphate and solubilizing agents ( sodium lauryl sulphate and polyethylene glycol 6000) were utilized to study their effect on the release profile of drug from ethyl cellulose matrices. It was found that sodium carboxymethyl cellulose increased the carbamazepine release and the same effect was obtained when the same amount of microcrystalline cellulose used
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