초록 ▼

A microwave vacuum oven for quickly removing volatile material from laboratory samples: The oven has a vacuum chamber for receiving the samples in a closed vessel and a vacuum source for expelling volatile material. This vessel has preferably a deformable gasket for sealing engagement with a top and

A microwave vacuum oven for quickly removing volatile material from laboratory samples: The oven has a vacuum chamber for receiving the samples in a closed vessel and a vacuum source for expelling volatile material. This vessel has preferably a deformable gasket for sealing engagement with a top and bottom portion, and a gas passage is also provided therein for easily removing the top portion. Auxiliary components are also disclosed for gradually decreasing the microwave energy output in accordance with residual volatile material present at a given time in a system. A method described includes (a) maintaining a vacuum environment around a sample containing volatile material, (b) subjecting the sample to microwave radiation energy, to rapidly liberate its volatile material while measuring the rate of volatilization of the sample over time, (c) detecting the point at which said rate of volatilization decreases, (d) at said point decreasing the amount of radiation energy generated into said sample, while maintaining vacuum and continuing detecting the rate of volatilization, until said rate stops, indicative that said volatile material is completely liberated from said sample, and (e) stopping the radiation at or near the point at which said volatile material is completely liberated from said sample while said vacuum is maintained until the environment surrounding said sample is substantially free from any volatile material liberated from said sample.

대표청구항 ▼

A microwave vacuum oven for rapidly determining the volatile material content in samples susceptible to damage due to pyrolysis and heat degeneration comprising in combination: a vacuum chamber for receiving at least one open sample container containing at least one sample to be tested, and in combi

A microwave vacuum oven for rapidly determining the volatile material content in samples susceptible to damage due to pyrolysis and heat degeneration comprising in combination: a vacuum chamber for receiving at least one open sample container containing at least one sample to be tested, and in combination therewith, a microwave source for rapidly liberating volatile material from said at least one sample, adjusting means for varying the energy emitted from said microwave source, a valve means connected to said chamber for alternatively creating a vacuum in said chamber or releasing from said chamber said vacuum, or releasing from said chamber said vacuum, means to detect the liberation of the volatile material out of said vacuum chamber, means to determine the rate of volatilization of said sample, means to convert said rate of volatilization as a signal, and to convey and sense said signal to a control means to determine said rate of volatilization of said at least one sample over time, and wherein (said adjusting means responsive to) said control means delivers an input to said adjusting means, whereby said adjusting means automatically varies the energy emitted from said microwave source, whereby upon vacuum conditions and initial heating the rate of volatilization decreases, and at near a point of inflection when said rate of volatilization decreases, said control means actuates said adjustment means to lower said microwave energy, while maintaining said vacuum in said chamber throughout until said means to detect liberation of the volatile material out of said vacuum chamber detects complete liberation of the volatile material out of said vacuum chamber, and thereafter releasing from said chamber, said vacuum with said valve means.