摘要:
A method of fracturing a subterranean formation which surrounds a well bore comprises the steps of providing a fracturing fluid, and injecting the fracturing fluid into the well bore at a pressure sufficient to form fractures in the subterranean formation which surrounds the well bore. The pressure is then released from the fracturing fluid, after which the fluid may be removed from the well and the well placed into production. The fracturing fluid comprises an aqueous liquid, a polysaccharide soluble or dispersible in the aqueous liquid in an amount sufficient to increase the viscosity of the aqueous liquid, an enzyme breaker which degrades said polysaccharide at a temperature above 180° F. Fracturing fluid compositions and enzyme breaker systems useful for carrying out the invention are also disclosed.
摘要:
A method of fracturing a subterranean formation which surrounds a well bore comprises the steps of providing a fracturing fluid, and injecting the fracturing fluid into the well bore at a pressure sufficient to form fractures in the subterranean formation which surrounds the well bore. The pressure is then released from the fracturing fluid, after which the fluid may be removed from the well and the well placed into production. The fracturing fluid comprises an aqueous liquid, a polysaccharide soluble or dispersible in the aqueous liquid in an amount sufficient to increase the viscosity of the aqueous liquid, an enzyme breaker which degrades said polysaccharide at a temperature above 180° F. Fracturing fluid compositions and enzyme breaker systems useful for carrying out the invention are also disclosed.
摘要:
A process for producing a ceramic composite having a porous network. The process includes providing a photocurable ceramic dispersion. The dispersion consists of a photocurable polymer and a ceramic composition. The surface of the dispersion is scanned with a laser to cure the photocurable polymer to produce a photocured polymer/ceramic composition. The photocured composition useful as a polymer/ceramic composite, or the polymer phase can be removed by heating to a first temperature that is sufficient to burn out the photocured polymer. It is then heated to a second temperature that is higher than the first temperature and is sufficient to sinter the ceramic composition to produce a purely ceramic composition having a porous network. Preferably and more specifically, the process uses a stereolithographic technique for laser scanning. The process can form a high quality orthopedic implant that dimensionally matches the bone structure of a patient. The technique relies upon laser photocuring a dense colloidal dispersion into a desired complex three-dimensional shape. The shape is obtained from a CAT scan file of a bone and is rendered into a CAD file that is readable by the stereolithography instrument. Or the shape is obtained directly from a CAD file that is readable by the stereolithography instrument.
摘要:
A method of fracturing a subterranean formation which surrounds a well bore comprises the steps of providing a fracturing fluid, and injecting the fracturing fluid into the well bore at a pressure sufficient to form fractures in the subterranean formation which surrounds the well bore. The pressure is then released from the fracturing fluid, after which the fluid may be removed from the well and the well placed into production. The fracturing fluid comprises an aqueous liquid, a polysaccharide soluble or dispersible in the aqueous liquid in an amount sufficient to increase the viscosity of the aqueous liquid, an enzyme breaker which degrades the polysaccharide at a temperature above 180° F. Fracturing fluid compositions and enzyme breaker systems useful for carrying out the invention are also disclosed.
摘要:
Miniaturized linear and rotary electrostatic motors. The motors are fabricated by disposing a plurality of conductive lands onto insulating substrates and then filling in the spaces between the lands by deposition of an insulating material. A final layer of insulating material is then disposed over each of the entire surfaces containing the lands to form smooth bearing surfaces. The bearing surfaces of two of these elements are placed in contact. In one embodiment, the natural lubrication of the bearing surfaces aids movement. In another embodiment, a special lubricating film is placed between the substrates. Arrangements are made for maintaining alignment of the contacting elements. The lands are selectively energized in a manner to effect movement of one element with respect to the other.
摘要:
This invention discloses a process for making nanoparticles of amphiphilic copolymers by flash precipitation. Nanoparticles may be of amphiphilic copolymer alone or may contain an additive target molecule, preferably an organic active. The inclusion of additive target molecules in amphiphilic copolymer nanoparticles can alter their water solubility characteristics, fluid dynamics, and/or stability. Changing an additive target molecule's solubility and stability in a nanoparticle can make a water insoluble compound suitable for pharmaceutical administration as well as specifically target the molecule to a specific area of a patient's body. The process affords the production of nanoparticles at high absolute active content, at high yield, high productivity, and high processing rates while using unusually low amounts of amphiphilic copolymers. Furthermore, the resulting particles exhibit sufficient stability for post processing as desired. The invention also discloses two apparatuses for the production of nanoparticles of amphiphilic copolymers by flash precipitation.
摘要:
The invention described herein relates to sterically stabilized colloidal constructs comprising preformed colloidal particles encapsulated within a polymeric shell. The constructs, which are controllably sized, are nanoparticles comprising hydrophobic elements, electrostatically charged particles with hydrophobic surfaces, hydrophobic inorganic nanostructures, and amphiphilic copolymers with hydrophobic domains and hydrophilic domains. The constructs are made by a process that allows for the simultaneous encapsulation of a preformed colloidal agent as well as a dissolved hydrophobic active within the core of the polymeric nanoparticle. Among the actives incorporated in various embodiments are organic fluorescent dyes, metal nanostructures and superparamagnetic materials for use in combined fluorescence, optical and magnetic resonance imaging applications, and hydrophobic drugs for therapeutic applications.
摘要:
The present invention provides a process for producing lipid nanoparticles encapsulating therapeutic products, said process comprising: a) providing one or more aqueous solutions in one or more reservoirs; b) providing one or more organic solutions in one or more reservoirs, wherein one or more of the organic solutions contains a lipid and wherein one or more of the aqueous solutions and/or one or more of the organic solutions includes therapeutic products; c) mixing said one or more aqueous solutions with said one or more organic solutions in a first mixing region, wherein said first mixing region is a Multi-Inlet Vortex Mixer (MIVM), wherein said one or more aqueous solutions and said one or more organic solutions are introduced tangentially into a mixing chamber within the MIVM so as to substantially instantaneously produce a lipid nanoparticle solution containing lipid nanoparticles encapsulating therapeutic products.
摘要:
This invention discloses a process for making nanoparticles of amphiphilic copolymers by flash precipitation. Nanoparticles may be of amphiphilic copolymer alone or may contain an additive target molecule, preferably an organic active. The inclusion of additive target molecules in amphiphilic copolymer nanoparticles can alter their water solubility characteristics, fluid dynamics, and/or stability. Changing an additive target molecule's solubility and stability in a nanoparticle can make a water insoluble compound suitable for pharmaceutical administration as well as specifically target the molecule to a specific area of a patient's body. The process affords the production of nanoparticles at high absolute active content, at high yield, high productivity, and high processing rates while using unusually low amounts of amphiphilic copolymers. Furthermore, the resulting particles exhibit sufficient stability for post processing as desired. The invention also discloses two apparatuses for the production of nanoparticles of amphiphilic copolymers by flash precipitation.
摘要:
A gas storage cylinder or gas storage cylinder liner, formed from a polymer composite, containing at least one polymer and a modified graphite oxide material, which is a thermally exfoliated graphite oxide with a surface area of from about 300 m2/g to 2600 m2/g.
摘要翻译:包含至少一种聚合物和改性氧化石墨材料的由聚合物复合材料形成的储气罐或气体存储缸套,其是表面积为约300m 2 / g至2600m 2 / m 2的热剥离石墨氧化物, G。