Abstract: Electron beam and gamma radiation crosslinked, silicone gel adhesives are described. Both nonfunctional and functional poly diorganosiloxanes are used. Methods of forming the adhesives, and medical articles incorporating such adhesives are also described.

Abstract: Electron beam and gamma radiation crosslinked, silicone gel adhesives are described. Both nonfunctional and functional poly diorganosiloxanes are used. Methods of forming the adhesives, and medical articles incorporating such adhesives are also described.

Abstract: A method for maintaining the activity of silicoaluminophosphate (SAPO) molecular sieve catalyst particles during oxygenate to olefin conversion reactions. After regeneration of SAPO catalyst particles, the regenerated particles are mixed with particles having coke on their surface in a manner that maintains their catalytic activity at a predetermined level.

Abstract: The invention is directed to methods for protecting metalloaluminophosphate molecular sieves, particularly silicoaluminophosphate (SAPO) molecular sieves, from loss of catalytic activity due to contact with a gas containing water. The methods of the invention provide procedures that enable activated sieve to contact water vapor, within a certain range of time, temperature, and water partial pressure conditions, before the sieve becomes substantially deactivated.

Abstract: An apparatus for increasing efficiency and reducing heat dissipation in power converters is disclosed. Zero-voltage-switching (ZVS) can reduce switching loss of power converters but it often results in a very complicated design and only works well under constant output current. In order to allow the ZVS to work over a wide loading range, the transformer secondary current is blocked when the primary starts to resonate. Hence, the resonant voltage waveform across the switch will not change even when the loading current is changing. Such a resonant voltage waveform is obtained with the aid of the transformer primary inductance and capacitor(s). Also provided is a novel driving circuit which controls the switching. Alternatives and variations of this apparatus can be made to satisfy different applications such as power conversion and power inversion. The subject power converter significantly lowers the heat loss and achieves higher efficiency for very wide loading ranges.

Abstract: A process is described for converting an oxygenate-containing feedstock into one or more olefins in a reactor system including a plurality of fixed bed reactors each containing a catalyst composition comprising a molecular sieve and at least one metal oxide having an uptake of carbon dioxide at 100° C. of at least 0.03 mg/m2 of the metal oxide. Each reactor is sequentially rotated between at least one operating mode, wherein the catalyst composition in the reactor is contacted with the oxygenate-containing feedstock, and a regeneration mode, wherein the catalyst composition in the reactor is contacted with a regeneration medium.

Abstract: A process is described for converting an oxygenate-containing feedstock into one or more olefins in a moving bed reactor system operating in countercurrent flow using a catalyst composition comprising a molecular sieve and at least one metal oxide having an uptake of carbon dioxide at 100° C. of at least 0.03 mg/m2 of the metal oxide.

Abstract: A process is described for converting an oxygenate-containing feedstock into one or more olefins in which the feedstock is contacted in a reaction zone with a fluidized bed of a particulate catalyst composition comprising a molecular sieve and at least one metal oxide having an uptake of carbon dioxide at 100° C. of at least 0.03 mg/m2 of the metal oxide whereby at least part of the feedstock is converted into a product stream comprising one or more olefins and a carbonaceous material is deposited on the catalyst composition to produce a coked catalyst composition. The coked catalyst composition is separated from the product stream and divided into at least first and second portions. The first portion of the coked catalyst composition is contacted with a regeneration medium in a regeneration zone under conditions to remove at least part of the carbonaceous material from the coked catalyst composition and produce a regenerated catalyst composition, which is subsequently recycled to the reaction zone.

Abstract: A method for maintaining the activity of silicoaluminophosphate (SAPO) molecular sieve catalyst particles during oxygenate to olefin conversion reactions. After regeneration of SAPO catalyst particles, the regenerated particles are mixed with particles having coke on their surface in a manner that maintains their catalytic activity at a predetermined level.

Abstract: The invention is directed to methods of shutting down reaction systems. The reaction systems are those that use catalysts that comprise molecular sieves, particularly metalloaluminophosphate molecular sieves, especially metalloaluminophosphate molecular sieves which are susceptible to loss of catalytic activity due to contact with water molecules. The methods provide appropriate mechanisms of stopping feed to the reactor and unloading catalyst to protect against loss of catalytic activity that can occur due to contact with water molecules.

Abstract: The invention is directed to methods of starting up reaction systems. The reaction systems are those that use catalysts that comprise molecular sieves, particularly metalloaluminophosphate molecular sieves, especially metalloaluminophosphate molecular sieves which are susceptible to loss of catalytic activity due to contact with water molecules. The methods provide appropriate mechanisms of heating and loading the activated molecular sieves to protect against loss of catalytic activity that can occur due to contact with water molecules.