Titanium oxide nanoparticles-modified smectite (SMC-nTiO2) as a low-cost adsorbent was investigated for the removal of Rhodamine B (RhB) from aqueous solutions. The adsorbents (SMC and SMC-nTiO2) were characterized by scanning electron microscopy, Fourier transforms infrared spectroscopy, and energy-dispersive X-ray spectroscopy. The effects of various parameters like contact time, adsorbent weight, pH, and temperatures were examined. Three kinetic equations (pseudo-first-order (PFO), pseudo-second-order (PSO), and intra-particle diffusion) were used to evaluate the experimental kinetic of the data and the results showed that the adsorption process is in line with the PSO kinetic model. Adsorption equilibrium isotherms were modeled using Langmuir, Freundlich, and Temkin equations. The removal processes of RhB onto SMC and SMC-nTiO2 were fitted well by the Freundlich isotherm. The maximum cationic dye removal of 91.4% and 99.9% were obtained at pH 9.04, for the adsorbent surfaces SMC and SMC-nTiO2, respectively. Thermodynamic parameters such as ΔG°, ΔH°, ΔS°, and Ea were also estimated for the whole process. The error function, the nonlinear Chi-square test (χ2) have been also determined. Titanium oxide nanoparticles- modified smectite clay sample shows very good potential as a low-cost adsorbent for the removal of RhB from aqueous solutions.
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The aim of this research is to construct a cognitive behavior program based on the theory of Meichenbaum in reducing the emotional sensitivity among Intermediate school students. To achieve the aims of the research, two hypotheses were formulated and the experimental design with equal groups was chosen. The population of research and its sample are determined. The test of negative emotional sensitivity, which is constructed by the researcher, was adopted. The test contains (20) items proved validity and reliability as a reliable test by presenting it to a group of arbitrators and experts in education and psychology. An educational program is constructed based on the theory of Meichenbaum. The test was applied to a sample of (60) second i
... Show MoreObjective. This study aimed to evaluate the orthodontic bond strength and enamel-preserving ability of a hydroxyapatite nanoparticles-containingself-etch system following exposure to various ageing methods. Materials and Methods. Hydroxyapatite nanoparticles (nHAp) were incorporated into an orthodontic self-etch primer (SEP, Transbond™ plus) in three different concentrations (5%, 7%, and 9% wt) and tested versus the plain SEP (control) for shear bond strength (SBS), adhesive remnant index (ARI) scores, and enamel damage in range-finding experiments using premolar teeth. The best-performing formulation was further exposed to the following four artificial ageing methods: initial debonding, 24 h water storage, one-month water stora
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This paper presents a comparative study of two learning algorithms for the nonlinear PID neural trajectory tracking controller for mobile robot in order to follow a pre-defined path. As simple and fast tuning technique, genetic and particle swarm optimization algorithms are used to tune the nonlinear PID neural controller's parameters to find the best velocities control actions of the right wheel and left wheel for the real mobile robot. Polywog wavelet activation function is used in the structure of the nonlinear PID neural controller. Simulation results (Matlab) and experimental work (LabVIEW) show that the proposed nonlinear PID controller with PSO
learning algorithm is more effective and robust than genetic learning algorithm; thi
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The study was carried out to determine the cytotoxic, antioxidant and gastro-protective effect of ethyl-4-[(3,5-di-tert-butyl-2-hydroxybenzylid ene)amino] benzoate (ETHAB) in rats.
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Abstract:
The tax is one of the elements of the general revenues of the state and contributes to covering its expenses. Taxes are imposed in most countries of the world. The tax proceeds depend on a set of factors that contribute either positively or negatively to the tax share by increasing or decreasing it. Therefore, the research aims to demonstrate the role of the tax examiner's procedures in achieving the validity of the taxable base and its reflection on the tax proceeds, as well as reviewing the tax examiner's procedures related to the tax return process. Examination and tax audit of the financial statements, as well as presenting the financial statements to an independent and i
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