Abstract: Systems and methods for measuring a volume of a ballonet are provided. In some aspects, the system may include a plurality of sensors configured to transmit a plurality of signals toward an interior surface of the ballonet and to receive the plurality of signals reflected off of the interior surface of the ballonet, a distance calculating module configured to calculate a plurality of distances from the plurality of sensors to the interior surface of the ballonet using the received plurality of signals, and a mapping module configured to create a three-dimensional surface using the calculated plurality of distances. The system may further include a measurement module configured to calculate the volume of the ballonet using the three-dimensional surface.

Abstract: Systems and methods for measuring a volume of a ballonet are provided. In some aspects, the system may include a plurality of sensors configured to transmit a plurality of signals toward an interior surface of the ballonet and to receive the plurality of signals reflected off of the interior surface of the ballonet, a distance calculating module configured to calculate a plurality of distances from the plurality of sensors to the interior surface of the ballonet using the received plurality of signals, and a mapping module configured to create a three-dimensional surface using the calculated plurality of distances. The system may further include a measurement module configured to calculate the volume of the ballonet using the three-dimensional surface.

Abstract: A method of reacting a toluenesulfonyl-terminated polyoxyethylene compound having the formula CH3—C6H4—SO2—(O—CH2—CH2)n—O—R1 with an ammonium salt having the formula NR24X to form a compound having the formula X—CH2—CH2—(O—CH2—CH2)n-1—R3. The value n is a positive integer. X is a halogen, cyanide, cyanate, thiocyanate, or azide. R1 is a terminating group. Each R2 is hydrogen or an alkyl group. —R3 is —O—R1 or —X.

Abstract: A method of reacting a toluenesulfonyl-terminated polyoxyethylene compound having the formula CH3—C6H4—SO2—(O—CH2—CH2)n—O—R1 with an ammonium salt having the formula NR24X to form a compound having the formula X—CH2—CH2—(O—CH2—CH2)n-1—R3. The value n is a positive integer. X is a halogen, cyanide, cyanate, thiocyanate, or azide. R1 is a terminating group. Each R2 is hydrogen or an alkyl group. —R3 is —O—R1 or —X.

Abstract: A method of thioacetate deprotection by providing a compound of the formula R1—S—CO—R2, and reacting the compound with a quaternary ammonium cyanide salt in the presence of a protic solvent in an inert atmosphere to convert the compound to a product of the formula R1—SH. R1 is an organic group in which the bonding to sulfur is through a saturated carbon, and R2 is an aliphatic group.