Abstract: A combination for carrying out microwave assisted reactions is disclosed, such as acid digestion and solvent extraction. The combination includes a microwave transparent pressure-resistant reaction vessel and a flexible film fluoropolymer liner inside the reaction vessel. The flexible film liner has a size and shape that substantially conforms to the inner walls of the reaction vessel. A pressure-relief closure is positioned on the reaction vessel and the flexible film liner, and an infrared temperature detector that operates in wavelengths (frequencies) to which both the reaction vessel and the flexible liner are transparent, so that an exact fit and conductive heating to the outside of the reaction vessel are not required.

Abstract: An instrument and associated method are disclosed for preparing samples for column chromatography.

Abstract: A method and associated instrument are disclosed for increasing the sequential rate at which a series of microwave assisted chemical reactions that potentially generate high pressure can be carried out. The method includes the steps of opening a pressure-resistant valve on a microwave-transparent pressure-resistant vessel to define a unpressurized pathway through the valve into the vessel, inserting a tube through the pathway in the valve and into the vessel, transferring at least one composition into the vessel through the tube, removing the tube from the vessel and from the pathway in the valve, closing the valve to seal the vessel against pressure release, and exposing the vessel and its contents to microwave radiation.

Abstract: A method and associated instrument are disclosed for increasing the sequential rate at which a series of microwave assisted chemical reactions that potentially generate high pressure can be carried out.

Abstract: A method and associated apparatus are disclosed for microwave assisted content analysis. The method includes the steps of applying microwave radiation to a sample while concurrently rotating the sample while the microwave radiation is being applied and while concurrently weighing the sample and while measuring the temperature of the sample and controlling or moderating the microwaves applied to the sample based upon the measured temperature.

Abstract: A method and associated apparatus are disclosed for microwave assisted content analysis. The method includes the steps of applying microwave radiation to a sample while concurrently rotating the sample while the microwave radiation is being applied and while concurrently weighing the sample and while measuring the temperature of the sample and controlling or moderating the microwaves applied to the sample based upon the measured temperature.

Abstract: A valve that opens and closes in response to changes in the physical environment of the valve. This valve is particularly suited as a relief valve in a microwave system-based, closed vessel digestion procedure. This valve includes a pressure-deformable, resilient wall member having a fluid vent port, and an obstructing member that cooperates with the wall member to open and close the valve.Also provided is a lidded vessel employing this improved valve, an apparatus that includes a microwave system and this lidded vessel, and methods using this improved valve.

Abstract: An apparatus for controllably heating material, such as a material to be analyzed for volatiles or non-volatiles contents, directly and indirectly by microwave radiation, includes a chamber, in which the material to be heated is placed, a source of microwave radiation, for radiating onto materials in the chamber and for controllably heating such a material, and a support for such material, which support includes a matrix of a material which transmits microwave radiation, and also includes particulate material therein which absorbs microwave radiation. The absorptive material is one that has a Curie temperature, above which it is transmissive of microwave radiation, so as thereby to prevent excessive heating of the support and the supported material which is to be heated. The matrix material is stable and form-retaining at the Curie temperature of the dispersed material.

Abstract: The present invention provides an improved valve. This valve opens and closes in response to a change in the physical environment of the valve. This valve is particularly suited as a relief valve in a microwave system-based, closed vessel digestion procedure. This valve includes a pressure-deformable, resilient wall member having a fluid vent port, and an obstructing member that cooperates with the wall member to open and close the valve. Also provided is a lidded vessel employing this improved valve, an apparatus that includes a microwave system and this lidded vessel, and methods using this improved valve.

Abstract: A method of sizing thermoplastic foamed cigarette filter rods and apparatus therefore. The apparatus comprises a rotating drum member having a plurality of stationary heated block members mounted about the periphery thereof. The block members are positioned such that a specific gap is created through which the thermoplastic polymeric filter rods are rolled and compressed to a uniform circumference.

Abstract: An apparatus for controllably heating material directly and indirectly by microwave radiation comprises a chamber in which the material to be heated (often to dryness, as for analysis) is placed, a source of microwave radiation for radiating into materials in such chamber for controllably heating such a material, and a support for such material, which support comprises a matrix of microwave radiation-transmissive material and a particulate microwave absorptive material dispersed in such matric material, which microwave absorptive material has a Curie temperature, above which it becomes microwave transmissive, so as thereby to prevent excessive heating of the support and the material thereon which is to be controllably heated, and which matrix material is stable and form-retaining at the Curie temperature of the dispersed material.

Abstract: An apparatus for ashing materials which comprises a chamber, a source of microwave radiation for direction onto contents of the chamber, and in the chamber a support, such as a fused quartz pad or crucible, for the material to be ashed, and an ashing means of a stable microwave absorptive material, capable of being heated to high temperature by microwave radiation, such as a flat block of silicon carbide or a plurality of such blocks with openings therein to accommodate the crucible. The ashing means is in contact with the support for the material to be ashed and is capable of heating such support and such material to an ashing temperature.