Abstract:
A pretreatment process is disclosed for increasing conversion of reforming catalysts wherein the catalyst is treated at from 120.degree. C. to 260.degree. C.; then the temperature of the treated catalyst is maintained at a temperature of from 370.degree. C. to 600.degree. C. in a reducing atmosphere prior to starting the hydrocarbon feed. Preferably, the catalyst is treated in the presence of hydrogen at atmospheric pressure for at least twenty minutes; then the temperature of the treated catalyst is maintained at 475.degree. C. in a reducing atmosphere for at least ten minutes prior to starting the hydrocarbon feed.
Abstract:
A hydrocarbon conversion process is disclosed wherein a hydrocarbon feed is contacted with a dehydrocyclization catalyst containing a large-pore zeolite and a Group VIII metal, then the resulting reformate is upgraded using an intermediate pore size zeolite.
Abstract:
A flow channel suitable for use with a peristaltic pump comprises: an upper wall having a bowed upward shape; a lower wall having one of a bowed downward shape and a flat shape; and one or more spacers between the upper wall and the lower wall disposed between lateral edges of the upper and lower walls, each spacer having a height. The upper wall, lower wall, and the one or more spacers define a lumen. When the upper wall is compressed toward the lower wall by compressing members, the one or more spacers limit vertical movement of the compressing members such that the lumen is maintained in an under-occluded condition. In some cases, the bowing of one of the upper and lower walls has a recurved shape.
Abstract:
A selectable IOP valve for implantation in an eye of a patient controls IOP and/or bleb pressure. The valve includes a drainage tube configured to convey aqueous from an anterior chamber of an eye and includes a selectable flow control valve in fluid communication with the drainage tube and configured to control flow rates of the aqueous. The valve system includes a plurality of flow control pathways arranged to operate in parallel with each other, each of the flow control pathways being in communication with an entry port to the valve system. A flow control mechanism controls aqueous flow through the pathways. Methods and systems are also disclosed.
Abstract:
Embodiments generally relate to methods and apparatuses for generating ice. In one embodiment, a material is introduced to water, and the temperature of the combination of the water and the material is lowered until ice forms, the formed ice having a higher albedo than it would have had if the step of lowering the temperature had been carried out on the water without first carrying out the step of introducing the material. In one embodiment, the material is selected such that an aqueous solution of the material is alkaline. In another embodiment, a material is introduced to water, and the temperature of the combination of the water and the material is lowered until ice forms, the ice forming at a faster rate than the rate at which it would have formed if the material had not been introduced to the water.
Abstract:
An implantable MEMS package for the treatment of an ocular condition is provided. The MEMS package includes an outer portion; an active portion attached to the outer portion, the active portion including a fluid regulating element having a moving element; and a fluidic channel at an interface of the outer portion and the active portion. The fluidic channel is formed in at least one of the outer and active portions and permits fluid communication from the MEMS package to the fluid regulating element. A method for forming a MEMS package as above is also provided. An ocular implant for treating glaucoma including an inlet tube for receiving aqueous humor; a MEMS package as above, coupled to the inlet tube; a control system to control the MEMS package; and an outlet tube for draining aqueous humor at a drainage location, is provided.
Abstract:
Glaucoma drainage devices including vario-stable valves and associated systems and methods are disclosed. A glaucoma drainage device includes a drainage lumen and a valve system coupled to the drainage lumen to control the flow of fluid through the drainage lumen. The valve system includes an adjustable valve with a diaphragm that is in communication with the drainage lumen and is movable to occupy varying amounts of the drainage lumen. In some embodiments, the valve system is maintained in a desired position without the use of power such that power is only needed when changing a position of the adjustable valve.
Abstract:
An apparatus includes a medicament container and an actuator assembly coupled to a proximal end portion of the medicament container. A distal end portion of the medicament container is configured to be coupled to a needle. A piston is movably disposed within the medicament container such that the medicament container is divided into a first internal portion and a second internal portion, the first internal portion containing a medicament. The actuator assembly has a pressurized fluid container, a regulator and a bias member. The pressurized fluid container is configured to move relative to the medicament container between a first position and a second position. The regulator is configured to fluidically couple the pressurized fluid container and the second internal portion of the medicament container when the pressurized fluid container is in the second position. The bias member is configured to bias the pressurized fluid container in the first position.
Abstract:
A method for fabricating a suspended structure including a layer of membrane material over a substrate. The suspended structure overlies a cavity in the substrate. The method starts by generating a sacrificial layer comprising a first material that can withstand temperatures typically encountered in subsequent conventional semiconductor processing steps. In the preferred embodiment of the present invention, the bond between sacrificial layer and the underlying substrate must be capable of withstanding temperatures greater than the Si—Al eutectic point. A layer of membrane material is then deposited over the sacrificial layer. The membrane material comprises a second material different from the first material. An opening is introduced in the layer of membrane material thereby exposing the sacrificial layer. A first etchant is applied to the sacrificial layer through the opening until the sacrificial layer is removed leaving a portion of the cavity. The first etchant is chosen such that the first etchant removes the first material more rapidly than the second material. Finally, a second etchant is introduced into the cavity to expand the cavity. The second etchant is chosen such that the second etchant removes the substrate more rapidly than the second material. The first material is preferably PSG, thermal silicon dioxide, low temperature oxide, or tungsten.