Search results
Results from the WOW.Com Content Network
A common theme among these techniques is the use of a fine (10 0 –10 −3 Torr) or high (10 −3 –10 −6 Torr) vacuum to remove air, and the use of an inert gas: preferably argon, but often nitrogen. The two most common types of air-free technique involve the use of a glovebox and a Schlenk line, although some rigorous applications use a ...
Vacuum Assisted Resin Transfer Molding (VARTM) or Vacuum Injected Molding (VIM) is a closed mold, out of autoclave (OOA) [1] composite manufacturing process. VARTM is a variation of Resin Transfer Molding (RTM) with its distinguishing characteristic being the replacement of the top portion of a mold tool with a vacuum bag and the use of a vacuum to assist in resin flow. [2]
Air abrasion is a dental technique that uses compressed air to propel a thin stream of abrasive particles—often aluminum oxide or silica—through a specialized hand-piece to remove tooth tissue and decay before being suctioned away, similar to sand blasting.
A vacuum ejector, or simply ejector, or aspirator, is a type of vacuum pump, which produces vacuum by means of the Venturi effect.. In an ejector, a working fluid (liquid or gaseous) flows through a jet nozzle into a tube that first narrows and then expands in cross-sectional area.
The portable suction unit of an ambulance A dental vacuum system for central suction. In medicine, devices are sometimes necessary to create suction. Suction may be used to clear the airway of blood, saliva, vomit, or other secretions so that a patient may breathe. Suctioning can prevent pulmonary aspiration, which can lead to lung infections.
It utilizes a flexible film to enclose the part and seal it from the outside air. The vacuum bag material is accessible in a tube shape or a sheet of material. Then, a vacuum is drawn on the vacuum bag, and atmospheric pressure compresses the part during the cure. When a tube-shaped bag is used, the entire part can be enclosed within the bag.
Vacuum systems usually consist of gauges, vapor jet and pumps, vapor traps and valves along with other extensional piping. A vessel that is operating under vacuum system may be any of these types such as processing tank, steam simulator, particle accelerator, or any other type of space that has an enclosed chamber to maintain the system in less than atmospheric gas pressure.
The inert-gas line is vented through an oil bubbler, while solvent vapors and gaseous reaction products are prevented from contaminating the vacuum pump by a liquid-nitrogen or dry-ice/acetone cold trap. Special stopcocks or Teflon taps allow vacuum or inert gas to be selected without the need for placing the sample on a separate line. [3]