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A catalyzed hydrocarbon (HC) trap aiming at the super-ultra low emission vehicle (SULEV) regulation was developed using a metal-impregnated zeolite. To enhance the adsorption and to raise the desorption temperature for a wide range of HC species, the modification of zeolite with certain metals was needed and Ag was found to be the most promising. Using a Ag impregnated zeolite, a three way catalyst was prepared, and its HC purification ability for a model gas simulating cold-start HCs was studied. Its heat resistance was also examined. A vehicle test for a fresh catalyzed HC trap showed that the cold-start HC after the newly developed trap almost reached the SULEV regulation level.

Copper die-casting is still a relatively new casting process and the numerical formulation of this process is still in its developmental stages. A casting simulation software - ADSTEFAN was used to numerically determine the porosity in edge-gated copper rotor die-casting. The results obtained from simulation were then compared to the real die-cast copper rotors that were produced. Shot profiles are shown to be very instrumental in controlling porosity. Profiles designed to pre-fill a portion of the gate end ring at the slow shot speed prior to accelerating to the fast velocity to fill the conductor bars and ejector end ring are shown to be very effective in minimizing and controlling porosity. Since the electrical conductivity of copper is nearly 60% higher than that of aluminum, substituting copper for aluminum in the rotor would markedly increase the electrical efficiency of the motor.