Effect of co-doping two different elements and incorporating SrBi2Nb2O9 (SBN) on structure and field-stability of dielectric properties in PMNT ceramics were investigated. Single-phase cubic Perovskite structure is more easily obtained by appropriate co- doping of La3+ and Zn2+. X-ray diffraction patterns of PMNT/SBN composite showed that there is no SBN grains in PMNT/SBN as a secondary phase. Co-doping of La3+ and Zn2+ as well as incorporation of SBN markedly increased the field-stability of dielectric constant. The mechanism of improving field-stability was tentatively discussed.

A set of fuel supply system, in place of the carburetor, based on ultrasonic atomization is designed. The fuel for the new system which is atomized into micron grade fog grain with ultrasonic system, increases the fuel and air mixing contact area, make the fuel mix more uniform. The experimental results shows that the HC and CO conce-ntration in tail gas of new system has significantly lower,and CO2 is increased, which demonstrates the fuel burning more fully, achieve the effect of energy saving and emission reduction. The cost is quite to carburetor type.

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