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ORIGINAL RESEARCH ARTICLEpling agents or polymers via chemical reaction with the hydroxyl group of HA can be a good way of providing the strong interfacial adhesion between the inorganic fillers and the organic matrix (1, 4-6) which can lead to creation of composites with good mechanical properties. The disadvantages of these materials for tissue engineering applications are the lack of degradability in the biological environment, brittleness and existence of some limitations for fabrication of predesigned structures. A promising method for solving this problem can be use of polymeric capsules for mineral nucleation (1, 7). This method is based on the hydrophobic interaction of the surfactant with the polymer chain, leading to formation of surfactant micelles as a nanostructured template for nucleation of calcium phosphate minerals (8). Surfactant molecular geometry, concentration temperature and ionic strength are the main factors that can have an effect on micelle shape and size, which play an important role in controlling HA crystal size, shape and morphology (8-10).A few studies have explored the use of polymer-surfactant mixtures to nucleate and aggregate the calcium phosphate phase in aqueous medium. In these works, cationic surfactant has been applied (1, 9-11).The present study was focused on nucleation and growth of the inorganic part of the composite (HA) in the mixture of organic polymer (polyvinylpyrrolidone [PVP]) and anionic surfactant (sodium dodecyl sulfate [SDS]) as the template in aqueous media. It was expected that the SDS negative group would provide suitable sites for electrostatic bonding with calcium ions and act as initiator for HA nucleation. PVP is water soluble, biocompatible and reported as a useful polymer for biomedical applications (12, 13). PVP aqueous solution can be transformed,

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One of the aromatic contaminants in the oil and fuel is indole, which is toxic even at low doses and is considered as air and water pollutant. In this research, the surface of Zeolite 4A (Z4A) was modified by Cu(II)nanoparticles to introduce a desirable nanocomposite (Cu(II)/Z4A) for indole oxidative degradation. The catalysts characterization was carried out by XRD, SEM, EDS, FTIR, and BET/BJH techniques. Response Surface Methodology (RSM) based on Box-Behnken Design (BBD) was employed for studying several effective factors influences in indole oxidation process, including pH, weight percentage of loaded copper (Cu(wt %)), mass of composite, and indole initial concentration (IND concentration). The obtained results by BBD revealed the solution pH was the most pivotal factor in indole oxidative degradation and predicted that under the optimum experimental conditions, the efficiency should be 98.91%. Moreover, GC-mass analysis was applied for evaluating side products, of which results led to some mechanisms and new productions to be found by using indole oxidative degradation. The results also demonstrated that due to indole oxidation and applying the proper solvent (ethanol), some side products were generated capable of acting as a fuel octane number enhancer, which may play a significant role in obtaining more valuable fuels.