NiO-based ceramic has shown high dielectric constant with 103-105, as well as high dielectric loss. Previous studies showed that doping with monovalent cations can cause a considerable decrease in dielectric loss. In this research, the effect of Lithium carbonate (Li2CO3) dopant on NiO was investigated. The electroceramic of LixNi1-xO were prepared by using solid state reaction method. The mixture of Li+ and NiO were ball milled for 24 hours. The samples were calcined at 800oC for 6 hours, pressed into pellet shape at 750 MPa and sintered at 1200°C for 10 hours. The sintered pellets were subjected to XRD, SEM, density testing and Impedance analyzer. XRD result shows the single phase formation of LixNi1-xO. The grain becomes larger with the increament of Li+ mole %. The dielectric constant of LixNi1-xO decrease with the increasing frequency. The highest dielectric constant was observed in x= 0.03 with 5210 at frequency range of 1GHz to 1MHz.

Statistical design analysis (factorial design) was utilized to verify the significance and the interaction between the studied factors include temperature, reduction time and catalyst amount. Carbothermal reduction of iron ore sample was carried out at temperature between 1000°C to 1200°C. The effects of operating parameters studied were extent of reduction (X), carbon consumed (Cconsumed ) and nitridation (XN). Temperature was the most influential parameter that showed strong interaction with the operating parameters, meanwhile, reduction time and catalyst have showed the contrary results and had a very low percentage of contribution. The results of the experimental design showed that the extent of reduction reached up to 93% at 1200°C using 10 wt. % catalysts after 180 minutes reduction. The use of 0-10 wt % catalyst at 1200°C for 180 min reduction significantly affect the X but did not for Cconsumed and XN.Keywords: Carbothermal Reduction, Factorial Design, Malaysian Ilmenite, Nitridation.

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Numerous methods have been used to produce high purity TiC. There is no previous study has been reported on the formation using single elemental powders of Titanium (Ti) and Carbon (C) with addition Nickel (Ni) by tungsten inert gas (TIG) weld method. In this work, TiC was synthesized via TIG method by arc melting elemental powder mixture of Ti and C at ~5 second (s) and 80 ampere (A). The effect Ni contents on TiC formation was investigated. The mixed raw material was ball milled for 24 hours followed by synthesis via TIG method. The arced samples were characterized by X-ray diffraction (XRD) and Scanning electron microscope (SEM). It was revealed, that small amount of Ni additive to the metal powder allows the production of dense and tough TiC.