Abstract: The present invention relates to a new process for the preparation of substituted quinoxalines (I) by cyclization of the corresponding dianiline with 2,3 dihydroxy-1,4-dioxane. In a preferred embodiment, the invention provides a process for the preparation of compounds having the formula wherein Q is a nitrogen protecting group. Compounds of formula III and their derivatives are precursors to certain aryl fused azapolycyclic compounds which exhibit activity as agents for the treatment of neurological and psychological disorders.

Abstract: An apparatus and method for operating a fuel cell power system utilizing a low voltage power source and system power to power an airmover. The fuel cell power system uses a low voltage power source to power the airmover during start-up and transitions to using system power to power the airmover as the fuel cell stack increases its voltage output. During a shutdown operation the fuel cell power system transitions from using system power to using the low voltage power source to power the airmover enabling a purging operation to be performed. A controller coordinates the operation of the airmover between using the low voltage power source and using electrical power produced by the fuel cell stack to power the airmover.

Abstract: A fuel cell system that employs surge prevention by electronically mapping the compressor for discharge pressure versus mass airflow. In one embodiment, the fuel cell system employs a mass flow meter that measures the airflow to the compressor. A controller receives a signal from the mass flow meter indicative of the flow rate of the charge airflow to the compressor, and determines the outlet pressure and temperature of the compressor from the compressor speed and the measured airflow. This gives the compressor map location at which the compressor is operating. In another embodiment, the fuel cell system employs a pressure sensor that measures the output pressure of the compressor, and provides a pressure signal to the controller. The controller determines the mass airflow to the compressor to determine the compressor map location.

Abstract: A fuel cell system is provided for storing energy created from the reaction of residual gases at shutdown of a fuel cell stack. This energy can then be used for powering a component of the fuel cell stack and enables air to be used to purge the anode gas.

Abstract: A fuel cell system including a turbomachine compressor that delivers charge air to the cathode side of a fuel cell module. A bidirectional mass flow meter measures the airflow through the compressor, and provides an indication of a reverse airflow through the compressor for surge protection. A controller receives a signal from the mass flow meter indicative of the reverse flow. The controller controls a motor driving the compressor and a back pressure valve at the cathode exhaust of the fuel cell module to control the pressure in the fuel cell module to remove the surge condition.

Abstract: A variable capacity compressor that is operable in a normal mode and either an upward or downward rapid transient mode includes a compressor that compresses a fluid and a motor that drives the compressor. A controller powers the motor from a main power source when operating in the normal mode and powers the motor from a supplemental power source when operating in the upward rapid transient mode.