Abstract:
An osmotically driven fluid dispenser that is capable of being miniaturized and used as an implant to administer fluid drug compositions to animals and humans. The dispenser comprises a flexible inner bag adapted to contain the drug composition, a fluid tight plug fitted into the bag opening, a port in the plug through which the composition may be charged to the bag, an intermediate layer of an osmotically effective solute composition partly covering the bag exterior such that a band of the bag exterior proximate to the plugged end is not covered by the layer, an outer shape-retaining semipermeable membrane covering the layer of solute and forming a fluid tight seal at said band, and a tube that fits snugly through the port in the plug and extends substantially into the interior of the bag after the drug composition is charged to the bag, said tube providing an outlet through which the drug composition may be dispensed.
Abstract:
A device is disclosed comprised of a wall formed of a material collapsable in response to mechanical force and surrounding a closed compartment for containing an agent, a dispensing passageway communicates with the compartment and the exterior of the device for dispensing agent therefrom, a filling passageway communicates with the exterior of the device and the compartment for filling the device, a layer of an osmotically effective solute is deposited on the collapsable wall''s outer surface, said solute capable of exhibiting an osmotic pressure gradient against an external fluid and increasing its volume as fluid diffuses by osmosis into the solute, an outer wall surrounding the layer of solute formed of a material having shape retaining properties, permeable to the fluid and substantially impermeable to solute, and wherein the filling passageway houses a material penetrable to a means for filling the compartment which material self closes on removal of the means to maintain the compartment in closed condition for subsequent collapsing thereof in response to mechanical or hydrostatic force generated by osmotic pressure arising in the solute layer, as fluid diffuses therein to increase its volume and generate forces that are exerted between the collapsable wall of the agent containing chamber and the more rigid outer semi-permeable wall, which collapsing force in turn dispenses an agent through the dispensing passageway when the compartment is charged with drug and the device is positioned in the environment of use.
Abstract:
A process for the preparation of a high molecular weight polymer by a condensation process of a liquid reaction mixture wherein at least one volatile by-product is eliminated, characterized in that said condensation process is carried out in apparatus of such form and so operated that said reaction mixture being subjected to the condensation process has no free surface and removal of volatile product or products from said reaction mixture is effected by diffusion through at least a proportion of the wall of said apparatus which is permeable to said volatile product or products but not permeable to said reaction mixture or said polymer, said proportion of the wall which is permeable serving to separate said reaction mixture from a chemically inert gaseous fluid in which the partial pressure of the volatile byproduct, or of the volatile by-products, is continually maintained below the equilibrium partial pressure for the reaction mixture under the conditions of reaction.
Abstract:
The present disclosure discloses a functional fluid gating control system, which comprises a porous membrane and a functional fluid. The functional fluid at least partially infiltrates the porous membrane and cooperates to form a fluid gating pathway. The functional fluid and/or the porous membrane responds to at least one stimulus and undergoes a physical change or a chemical change to change the threshold pressure of the transport substance. A transport fluid being immiscible with the functional fluid is controlled to pass through the fluid gating system, and thus controllable transport and multiphase separation of materials are achieved. The stimulus of the present disclosure comprises a wide range of sources, and the stimulus responsiveness of the functional fluid and the porous membrane can be randomly and freely combined to adapt to multiple stimuli from complex external conditions and achieve intelligent controllability.
Abstract:
A method of converting C2 and/or higher alkanes to olefins by contacting a feedstock containing C2 and/or higher alkanes with a first surface of a metal composite membrane of a sintered homogenous mixture of an Al oxide or stabilized or partially stabilized Zr oxide ceramic powder and a metal powder of one or more of Pd, Nb, V, Zr, Ta and/or alloys or mixtures thereof. The alkanes dehydrogenate to olefins by contact with the first surface with substantially only atomic hydrogen from the dehydrogenation of the alkanes passing through the metal composite membrane. Apparatus for effecting the conversion and separation is also disclosed.
Abstract:
A device and method for increasing the mass transport rate of a chemical or electrochemical process at the solid and fluid interface in a fluid cell. The device includes a membrane in close contact with surface of the work piece, to separate the process cell into two chambers, so that fluid velocity at the work piece is controlled separately from the main cell flow. Thus the diffusion boundary layer is controlled and minimized by the rate that fluid is withdrawn from the work piece chamber.
Abstract:
An arrangement for a direct methanol fuel cell includes a fuel cartridge that supplies a source of fuel to the direct methanol fuel cell. The fuel cartridge has a surface area enhanced planar vaporization membrane residing in the fuel cartridge. The arrangement also includes a fuel reservoir that receives fuel from the fuel cartridge, the fuel reservoir arranged to deliver fuel to the fuel cell. The fuel reservoir also including a surface area enhanced planar vaporization membrane residing in the fuel reservoir. The combination of the surface area enhanced planar vaporization membranes residing in the fuel cartridge and reservoir provides a dual stage vaporization of fuel to the fuel cell. Other features included are passive or active arrangements to increase the temperature of the fuel or reduce pressure in the fuel container to enhance rate of vaporization.
Abstract:
This invention provides mixed conducting metal oxides particularly useful for the manufacture of catalytic membranes for gas-phase oxygen separation processes. The materials of this invention have the general formula:A.sub.x A'.sub.x A".sub.2-(x+x') B.sub.y B'.sub.y B".sub.2-(y+y') O.sub.5+z ;wherex and x' are greater than 0;y and y' are greater than 0;x+x' is less than or equal to 2;y+y' is less than or equal to 2;z is a number that makes the metal oxide charge neutral;A is an element selected from the f block lanthanide elements; A' is an element selected from Be, Mg, Ca, Sr, Ba and Ra;A" is an element selected from the f block lanthanides or Be, Mg, Ca, Sr, Ba and Ra; B is an element selected from the group consisting of Al, Ga, In or mixtures thereof; andB' and B" are different elements and are independently selected from the group of elements Mg or the d-block transition elements.The invention also provides methods for oxygen separation and oxygen enrichment of oxygen deficient gases which employ mixed conducting metal oxides of the above formula. Examples of the materials used for the preparation of the membrane includeA.sub.x Sr.sub.x' B.sub.y Fe.sub.y' Co.sub.2-(y+y') O.sub.5+z,wherex is about 0.3 to about 0.5,x' is about 1.5 to about 1.7,y is 0.6,y' is between about 1.0 and 1.4 andB is Ga or Al.
Abstract:
In a reactor and a method for the conversion of methanol to hydrogen wherein the reactor comprises first and second chambers divided by a membrane which is permeable for hydrogen and CO but not for CO.sub.2, the methanol is converted in the first chamber by a catalyst disposed therein to a gas mixture comprising hydrogen, carbon monoxide and carbon dioxide, and the hydrogen and carbon monoxide pass through the membrane into the second chamber wherein the CO is converted by another catalyst disposed therein to methane.