摘要:
An improved process for producing high activity and high selectivity supported palladium-gold catalysts is provided. The process involves calcining the support impregnated with a palladium salt and gold salt in a non-reducing atmosphere and at a temperature ranging from 100.degree. C. to 600.degree. C. prior to reducing the metals. Catalysts of the invention are useful for the production of vinyl acetate in the vapor phase by reaction of ethylene, acetic acid and oxygen.
摘要:
A method for pretreatment of a palladium-gold catalyst useful in the synthesis of vinyl acetate. A virgin catalyst, following reduction to the metallic palladium and gold, is first heated at elevated temperatures in the presence of an oxidizing agent such as air. The oxidizing agent is withdrawn and an inert gas such as nitrogen is introduced. The catalyst is heated against at a temperature up to 500.degree. C. in the presence of a reducing agent such as hydrogen or ethylene. Improvement in selectivity and yield are obtained.
摘要:
A method for pretreatment of a palladium-gold catalyst useful in the synthesis of vinyl acetate. A virgin catalyst, following reduction to the metallic palladium and gold, is first heated at elevated temperatures in the presence of an oxidizing agent such as air. The oxidizing agent is withdrawn and an inert gas such as nitrogen is introduced. The catalyst is heated again at a temperature up to 500.degree. C. in the presence of a reducing agent such as hydrogen or ethylene. Improvements in selectivity and yield are obtained.
摘要:
A process is disclosed for the carbonylation of an organic compound selected from the group consisting of an olefin, an alcohol, an acid and an ester. In this process the organic compound is reacted with carbon monoxide in the presence of a Group VIII metal-containing catalyst. The liquid carbonylation product solution of this reaction is conveyed to a separation zone maintained at a lower total pressure than is the pressure in the reaction zone. Simultaneously with the conveyance of the liquid product solution to the separation zone is the introduction therein of a carbon monoxide-containing gaseous stream, the carbon monoxide therein contributing a partial pressure of up to 30 psia of the total pressure in said separation zone. A portion of the liquid carbonylation product solution is flashed and removed from the separation zone. The unflashed liquid carbonylation product solution is recycled back into the reaction zone.
摘要:
A patient interface device includes a main frame and a headgear. The main frame includes a central support portion for supporting a cushion component and first and second arms extending from the central support portion. The headgear includes a support portion, and first and second straps extending therefrom. The first strap has a first pocket and the second strap has a second pocket, wherein the first arm is received and moveable within the first pocket along a longitudinal axis of the first strap and the second arm is received and moveable within the second pocket along a longitudinal axis of the second strap. The headgear also includes first and second fastening mechanisms for securing the headgear to the main frame, holding the first arm in a selected position within the first pocket and holding the second arm in a selected position within the second pocket.
摘要:
A method and system for performing invasive procedures includes a surgical robot which is controlled by a guidance system that uses time of flight calculations from RF transmitters embedded in the robot, surgical instrument, and patient anatomy. Sensors around the room detect RF transmissions emitted by the RF transmitters and drive the robot according to a preprogrammed trajectory entered into the guidance system.
摘要:
An interface apparatus identification system for a respiration machine such as, for example, a medical ventilator, includes a detection element which is adapted to communicate with the ventilator, a patient interface assembly including a patient interface apparatus for delivering a flow of gas from the ventilator to an airway of a patient, and a differentiating feature which is incorporated into the patient interface assembly. The patient interface apparatus is selected from a predetermined category such as, for example, a specific make or brand. The differentiating feature is detectable by the detection element to distinguish patient interface apparatus that fall within the predetermined category from those that do not. Operation of the respiration machine in conjunction with the patient interface apparatus is dependent upon detection of the differentiating feature by the detection element. An associated identification method is also disclosed.
摘要:
Skin-contact products with a transpiration function such as medical devices or medicinal products, of which face masks, aspirators, ventilators, breast pumps or wound dressings are examples are described especially a skin-contact product with a transpiration function with an improved microclimate at a patient interface material-skin contact area. In an embodiment a material system (10, 20, 30) is described that comprises a hydrophobic silicone base material (11, 21, 31) and a hydrophilic silicone material (12, 22, 32) that is combined with the hydrophobic base material (11, 21, 31). At least a part of the hydrophilic material (12, 22, 32) is in contact with a moist surface (50). The hydrophobic base material (11, 21, 31) provides mechanical and dynamical stability of the material system (10, 20, 30). The hydrophilic material (12, 22, 32) allows for uptake or for diffusion of moisture away from moist surface (50). The material system (10, 20, 30) is utilized to fabricate a patient interface material (41) and forehead pad (42) of a user or patient interface, such as face mask (40), for example, a patient interface mask for positive air pressure therapy. Furthermore, a novel composition for the preparation of hydrophilic silicone materials, suitable for use in the material system (10, 20, 30), is disclosed.
摘要:
A cooling enclosure for a valve includes an elongated housing body having a pair of housing portions and a pair of removable end plates, the pair of housing portions separable along at least one longitudinally-extending seam. Fastener devices are provided for securing the pair of housing portions engaged along the at least one longitudinal extending seam. One or more apertures are provided for accommodating a like number of valve fittings, and cooling air inlet and outlet openings are also provided in the housing body for supplying and removing cooling air to the housing body.
摘要:
A method and system for performing invasive procedures includes a surgical robot which is controlled by a guidance system that uses time of flight calculations from RF transmitters embedded in the robot, surgical instrument, and patient anatomy. Sensors around the room detect RF transmissions emitted by the RF transmitters and drive the robot according to a preprogrammed trajectory entered into the guidance system.