الفهرس 
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Abstract
Pollution and its harmful effects on the environment due to the rapid industrial development, particularly the aquatic environment, causes the serious rising environmental pollution problems and threats the marine life. Industries like automotive metal-finishing, pipe corrosion, mining,and metallurgical as well as metal plating industries discharge many different toxic heavy metals specially Co and Cu in the vicinity water drains. Due to the harmfulness of these heavy metals for humans, animals and plants; great efforts have exerted in order to remediate wastewater. Several techniques have been devised to treat wastewater containing heavy metals before their discharging into the environment. Among these techniques, adsorption provides a simple and powerful way for removing heavy metals from wastewater. Fish bones were used as a natural and low cost heavy metal sorbent (mainly Cu and Co) from synthetic wastewater. Fish bones composition consists mainly of hydroxy apatite [Ca10(PO4)6(OH)2 – HAP]. HAP serves as an effective adsorbent due to its high removal capacity for heavy metals by ion exchange process with calcium ions on the bone surface. The removal efficiency of the adsorbent was studied as a function of initial metal concentration, contact time and pH value. Laser-induced breakdown spectroscopy (LIBS) has been applied for qualitative and quantitative analysis of heavy metals adsorbed by fish bones. Optimal experimental conditions were evaluated for improving the sensitivity of LIBS technique through parametric dependence studies. For quantitative analysis, LIBS experimental parameters including delay time, gate width, and laser energy were optimized to overcome the heterogeneous matrix effect. In order to enhance the LIBS results, plasma temperature was measured using Boltzmann plot method and electron density was demonstrated to fulfill the local thermodynamic equilibrium condition. Furthermore, calibration curves were constructed based on Xray fluorescence (XRF) analysis technique, whereas, the limits of detection (LOD) for Cu and Co were calculated. The results were validated by comparing LIBS data with those obtained by XRF spectrometry. The results of the two techniques are strongly correlated which verified the feasibility of using LIBS to detect traces of heavy metals adsorbed from wastewater by fish bones, This study reflects the potential of using LIBS in environmental applications. The adsorption parameters were determined using Langmuir and Freundlich isotherms. The Freundlich isotherm provided the best correlation of Cu (II) and Co (II) adsorption onto fish bones. The applicability of the Lagergren kinetic model revealed that the adsorption process of both ions followed well the pseudo-second-order kinetic model.