Meaning: Membranous structure that functions as the circulatory system in mammal embryos until the heart becomes functional. Classified under: Nouns denoting animals. Synonyms: umbilical vesicle; vesicula umbilicus; vitelline sac; yolk sac. Hypernyms (vesicula umbilicus is a kind of...): sac (a structure resembling a bag in an animal)
electric fan; blower. Hypernyms (blower is a kind of...): fan (a device for creating a current of air by movement of a surface or surfaces) Meronyms (parts of blower): electric motor (a motor that converts electricity to mechanical work) fan blade (blade of a rotating fan)
Soot Blowers. Soot blowers are installed in most boilers for the removal of entrained soot and ash susceptible to slagging and fouling. Natural gas (or such clean fuel)-fired boilers are exceptions because there is no ash in the fuel to deposit on the HSs. Soot blowers remove.