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Observation on the effect of adding titanium oxide (TiO2) and magnesium oxide (MgO) on the sintering of α-alumina (Al2O3) has been performed. In this study, technical alumina used as basic material in which the sample is formed by the pressureless sintering/cold press and sintered at 1500°C which is lower than alumina sintering temperature at 1700°C. Elemental analysis, observation of microstructure, hardness, fracture toughness and density measurements were carried out to determine the physical and mechanical properties of alumina. The results indicate a change in the microstructure where the content of the platelet structure are much more than the equilateral structure. At sintering temperature of 1500°C, neck growth occurs at ceramics grain, supported by the results of the density test which indicate perfect compaction has occurred in this process.

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Microcantilever-based sensorshave been demonstrated to be a high sensitive sensor in sensing application areas of chemistry, physics, biology, and biomedical. To determine the sensor selectivity, the microcantilever surface must be coated by a sensitive layer. In this work, zinc oxide (ZnO) is prepared on the microcantilever surface as a sensitive layer by employing a crystal growth method. To confirm the elemental of ZnO sensitive layer, the coated microcantilever surface is characterized by energy dispersive spectroscopy (EDS). Next, we investigate the response of microcantilever sensor to CO 2 gas in dynamic mode operation. The results show that the microcantilever sensitively responds the gas, which is indicated by the change of resonance frequency. Moreover, the consistent sensing behavior with certain resonance frequency shift due to gas response over repetitive cycles is found. The quite small of response and recovery times indicate that the sensing performance of the microcantilever with ZnO sensitive layer has high repeatablility and high reproducibility.

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