Fuel cells have important applications in recent decades due to high-energy demands, fossil fuel depletions, and environmental pollution throughout world. Pt/Pd nanoparticles/polyoxometalate/ionic liquid (ILs) nanohybrid synthesized for the first time and characterized by transmission electron microscope, scanning electron microscope, X-ray photo electron spectroscopy, energydispersive X-ray spectroscopy and X-ray diffraction method. A cost-effective catalyst has been developed on Pt/Pd nanoparticles/polyoxometalate/ionic liquid nanohybrid. The developed catalyst based on bimetallic nanoparticle demonstrates effective methanol oxidation in comparison with catalysts on monometallic nanoparticle and polyoxometalate/ionic liquid nanohybrid.

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Hard, tough, lightweight boron-carbide-reactive metal composites, boron-carbide-aluminum composites, are produced. The ultrasonic velocity and attenuation were measured on B 4 C-Al-Ni ceramic-metal composites, which are sintered in the temperature range 500-1200• C, by using the pulse echo method. Ultrasonic velocity, ultrasonic attenuation and rate of screen heights of successive peaks were determined according to the pulse-echo method by using 2 MHz and 4 MHz probes. It was observed that the mean grain size of samples has been changed with the sintering temperature. The velocity was found to be pretty sample dependent at room temperature and increased with increasing sintering temperature. The ultrasonic attenuation at room temperature was found to be more sample dependent. The sintering temperature variation of ultrasonic attenuation exhibited broad minimum values around 1200• C and sharp maximum values at 500• C. The increase observed in the temperature variation of longitudinal velocities and attenuation has been qualitatively explained with the help of the temperature variation of decrease value.

This novel research, aimed to improve the properties of Na-bentonite water based drilling mud (WBDM) and reduce its cost by adding multi-walled carbon nanotubes functionalized with copper oxide nanoparticles (CuONPs/MWCNTs). For this purpose, fistly, copper oxide nanoparticles (CuONPs) and multi-walled carbon nanotubes (MWCNTs) were synthesized separately, then MWCNTs were functionalized with CuONPs by chemical vapor deposition (CVD) method. Secondly, CuONPs/MWCNTs were characterized by X-ray Photoelectron Spectroscopy (XPS) and Scanning Electron Microscopy (SEM). Thirdly, CuONPs/ MWCNTs nanocomposite was added to the WBDM at different rates (0.001 to 0.01% w/v). Finally, rheological, filtration loss and cake thickness property analyzes were performed according to API standarts. As a result of this study, a significant improvement was observed in the rheological and filtration loss properties of WBDM with the addition of small amounts of CuONPs/MWCNTs. In particular, plastic viscosity (PV), apparent viscosity (AV), yield point (YP), 10 s and 10 min values increased by 57%, 36.7%, 28%, 33.3% and 44.4% respectively, the value of fitration loss decreased by 13.8%. With this improvement will increase the lifetime of the drilling mud is determined and its costs will decrease.