Abstract: A capacitive sensor and control system is configured to detect the presence (or absence) of fluid within a container. Configured in a vat of a deep fryer, the sensor determines when a level of liquid within the vat is at or above the level of the sensor. The sensor is in communication with the control system and the sensor sends a signal to the control system representative of the presence or absence of liquid within the vat and at the level of the sensor. The controller receives the signal from the sensor, and allows operation of a fluid management system and its associated plumbing to maintain an appropriate level of liquid in the vat.

Abstract: The present invention involves, in addition to many unique substituted sapphyrins, a novel method for synthesizing sapphyrins with good efficiency and high yield. An improved 9-step synthesis of substituted sapphyrins, e.g., the two C.sub.2 symmetric sapphyrins, compounds 2 and 4 of FIG. 1C, is described herein. This synthesis involves as an important step the condensation between a tripyrrane diacid and a diformyl bipyrrole. The key tripyrrane component is prepared in three high-yield steps from readily available pyrrolic precursors and the bipyrrole portion is prepared in four steps from ethyl 3-methyl-4-methylpyrrole-2-carboxylate in roughly 33% yield overall.

Abstract: The present invention involves, in addition to many unique substituted sapphyrins, a novel method for synthesizing sapphyrins with good efficiency and high yield. An improved 9-step synthesis of substituted sapphyrins, e.g., the two C.sub.2 symmetric sapphyrins, compounds 2 and 4 of FIG. 1C, is described herein. This synthesis involves as an important step the condensation between a tripyrrane diacid and a diformyl bipyrrole. The key tripyrrane component is prepared in three high-yield steps from readily available pyrrolic precursors and the bipyrrole portion is prepared in four steps from ethyl 3-methyl-4-methylpyrrole-2-carboxylate in roughly 33% yield overall.