448 results about "Fluid viscosity" patented technology

The present invention provides a conductive adhesive agent capable of being diluted with a solvent to give good coating workability and allowing formation of a conductive joint excellent in both thermal conductivity and electrical conductivity by inhibiting a gas generated when a binder resin is heat-cured after attachment of a part. The conductive adhesive agent according to the present invention is a conductive adhesive agent wherein, based on 100 parts by weight of silver powder having an average particle diameter of micrometers, which is used for a conductive medium, e.g. as a main component, 1 to 10 parts by weight of silver fine particles having an average particle diameter of nanometers is used in combination therewith and 5 to 15 parts by weight of thermosetting resin as a binder resin component and 10 parts or less by weight of solvent for adjustment of a fluid viscosity are blended therein as essential components, and by selection of such a blending ratio, generation of a gas component during heating and curing of the thermosetting resin to prevent formation of voids, and at the same time, fabrication of a conductive joint excellent in thermal conductivity and electrical conductivity is achieved.

Aqueous well treatment fluid compositions with biocidal activity are disclosed comprising a polymer for modifying fluid viscosity in the aqueous fluid, an organic monocarboxylic peracid being present in an anti-microbial amount of about 1 ppm to about 1000 ppm, and a controlled amount of hydrogen peroxide also being present. Peracetic acid is the preferred peracid. The viscosity-modifying polymer in the aqueous well treatment fluid composition may serve to reduce friction in the fluid or increase fluid viscosity. A method of using such compositions is also disclosed.

The invention provides a multifunctional suture needle that may be used to draw a suture through tissue surrounding a wound while simultaneously delivering a bioactive fluid through the needle tip. The suture needle possesses an internal cavity capable of containing a fluid, and a fine aperture adjacent to the point of the needle through which the fluid may egress. The fluid may be driven from the needle through the needle tip with a compressed gas that is sealed within the cavity adjacent to the fluid. Alternatively a fluid conducting suture may be employed to deliver fluid through the internal passage of the suture needle and out the aperture adjacent to the tip of the needle. The rate at which the fluid is emitted from the suture needle may be controlled by carefully selecting the fluid viscosity, design of the needle or suture passages, and pressure applied to the fluid.

A lubricant composition for use as a concentrate and motor oil having an enhanced thermal conductivity. One preferred composition contains a lubricant composition, nanomaterial, and a dispersing agent or surfactant for the purpose of stabilizing the nanomaterial. One preferred nanomaterial is a high thermal conductivity graphite, exceeding 80 W/m in thermal conductivity. Carbon nano material or nanostructures such as nanotubes, nanofibrils, and nanoparticles formed by grounding and/or milling graphite to obtain a mean particle size less than 500 nm in diameter, and preferably less than 100 nm, and most preferably less than 50 nm. Other high thermal conductivity carbon materials are also acceptable. To confer long-term stability, the use of one or more chemical dispersants or surfactants is useful. The graphite nanomaterials contribute to the overall fluid viscosity and providing a very high viscosity index. Particle size and dispersing chemistry is controlled to get the desired combination of viscosity and thermal conductivity increase from the lubricant. The resulting fluids have unique properties due to the high thermal conductivity and high viscosity index of the suspended particles, as well as their small size.

A composition for enhancing fluid viscosity including a mixture of at least one cationic or cationizable polymer and at least one anionic or anionizable (hydrolysable) polymer. The composition has a zeta potential at 25° C. in the range of 0.5 to 100 mV or −0.5 to −100 mV, typically 1 to 60 mV or −1 to −60 mV, or is a precursor convertible at a temperature of 100 to 250° C. to the composition having a zeta potential at 25° C. of 0.5 to 100 mV or −0.5 to −100 mV, typically 1 to 60 mV or −1 to −60 mV. Typically the compositions exhibit salt tolerance and interaction of both polymers at very high temperatures (>300° F.) such that the system exhibits an increase of viscosity at extreme temperatures. The compositions are useful for hydraulic fracturing, enhanced oil recovery, subterranean acidization, personal care as well as home and industrial cleaners.

A method of acidizing a subterranean formation involves the use of a composition containing a solution of a viscoelastic amidoamine oxide surfactant and an HF-containing acidizing solution. The composition typically contains from about 0.1 to about 8 weight percent of surfactant solution and from about 92 to about 99.9 weight percent of HF-containing acidizing solution. The composition is pumped into the subterranean formation. As the acid reacts, the composition viscosifies and becomes a self-diverting agent created in-situ. When the acid is further spent, the fluid viscosity declines eventually returning to a low viscosity state, allowing for easy cleanup. The process allows for selective acidizing of less permeable zones of the formation and more uniform stimulation of the hydrocarbon bearing formulation.

Aqueous well treatment fluid compositions are disclosed comprising an aqueous fluid containing polymer or copolymer for modifying fluid viscosity of the aqueous fluid and, in addition, an agent for effecting a controlled reduction in the aqueous fluid viscosity in a subterranean environment. The viscosity-reducing agent comprises a dilute concentration of peracetic acid. A method of using such compositions in oil- and gas-field treatment operations is also disclosed.

Downhole wellbore tools are actuated by electrically controllable fluids energized by a magnetic field, for example. When energized, the viscosity state of the fluid may be increased by a degree depending on the fluid formulation. Reduction of the controllable fluid viscosity by terminating a magnetic field acting upon the fluid may permit in situ wellbore pressure to actuate a downhole device, such as a wellbore packer.

A method for shortening the shear recovery time of cationic, zwitterionic, and amphoteric viscoelastic surfactant fluid systems by adding an effective amount of a rheology enhancer selected from partially hydrolyzed polyvinyl ester and partially hydrolyzed polyacrylates. The rheology enhancer also increases fluid viscosity and very low rheology enhancer concentration is needed. Preferred surfactants are betaines and quaternary amines. The fluids are useful in oilfield treatments, for example fracturing and gravel packing.

Composition and method for shortening the shear recovery time of cationic, zwitterionic, and amphoteric viscoelastic surfactant fluid systems by adding an effective amount of a co-gelling agent selected from triblock oligomeric compounds having hydrophilic (for example polyether) and hydrophobic (for example alkyl) portions. The co-gelling agent also increases fluid viscosity and very low co-gelling agent concentration is needed. Preferred surfactants are betaines and quaternary amines. The fluids are useful in oilfield treatments, for example fracturing and gravel packing.

Microfluidic systems and methods including those that provide control of fluid flow are provided. Such systems and methods can be used, for example, to control pressure-driven flow based on the influence of channel geometry and the viscosity of one or more fluids inside the system. One method includes flowing a plug of a low viscosity fluid and a plug of a high viscosity fluid in a channel including a flow constriction region and a non-constriction region. In one embodiment, the low viscosity fluid flows at a first flow rate in the channel and the flow rate is not substantially affected by the flow constriction region. When the high viscosity fluid flows from the non-constriction region to the flow constriction region, the flow rates of the fluids decrease substantially, since the flow rates, in some systems, are influenced by the highest viscosity fluid flowing in the smallest cross-sectional area of the system (e.g., the flow constriction region). This causes the fluids to flow at the same flow rate at which the high viscosity fluid flows in the flow constriction region. Accordingly, by designing microfluidic systems with flow constriction regions positioned at particular locations and by choosing appropriate viscosities of fluids, a fluid can be made to speed up or slow down at different locations within the system without the use of valves and/or without external control.

A process for enhancing the productivity of a formation consists of introducing into the formation a viscoelastic fluid which contains at least one surfactant, at least one quaternary amine polyelectrolyte, water, and a non-aqueous solvent. The surfactant forms aggregation structures or vesicles. The fluid, which significantly enhances fluid viscosity and thermal stability, is particularly effective as a diverting fluid to divert an acid treatment package from a high permeability or damaged portion of a formation to a low permeability or undamaged portion of a formation as well as a fracturing fluid. In addition, the fluid is useful for sand control completion.

A method is disclosed for reducing sag in drilling and completion fluids and in workover fluids. The method employs a drilling fluid comprising a low molecular weight polyalkyl methacrylate with an average molecular weight ranging from about 40,000 to about 90,000. This additive does not result in increased viscosity of the fluid.

A formation fracturing method with which to mitigate risk to hydrocarbon productivity includes pumping fracturing fluid, during at least part of a fracturing job time period, into a well to fracture a formation; generating signals, within the fracturing job time period, in response to at least one dimension of the fracture; and further pumping fracturing fluid, within the fracturing job time period, into the well in response to the generated signals. Further pumping includes controlling at least one of a pump rate of the further pumping and a viscosity (either fluid viscosity or particulate concentration) of the further pumped fracturing fluid. Control can include comparing a measured magnitude of at least one dimension of the fracture represented by the generated signals with a predetermined modeled magnitude of the same dimension. Tiltmeters can be used to sense fracture height and width, for example.

The present invention includes systems and methods for determining the viscosity of a fluid within a fluid flow path. Such method may comprise flowing fluid through the fluid flow path and past a fixed flow restriction therein. The method may also comprise first sensing of a fluid pressure within the fluid flow path at a selected location upstream of the flow restriction. The method may also include limiting fluid flow in the fluid flow path upstream of such selected location. The method may further comprise second sensing of a fluid pressure within the fluid flow path at such selected location after such limiting. Such method includes determining the viscosity of the fluid based, at least in part, on any pressure difference from such first and second sensing.

Micromachine fluidic apparatus incorporates a free-standing tube section and electrodes to actuate or control the movement of the tube section, or to sense the movement of the tube section, or both. Electronic circuitry, which may be disposed on the same substrate as the fluidic portion of the apparatus, is used in conjunction with the tube and electrodes in conjunction with a variety of different applications, including fluid flow measurement, fluid density measurement, fluid viscosity measurement, fluid transport, separation and/or mixing. According to a particular embodiment, the free-standing section of the tube is resonated for fluid flow and density measurements according to the Coriolis effect. Capacitive/electrostatic actuation techniques are used to control or resonate the free-standing section of the tube, and to detect variations in tube movement. Different methods of fabricating micromachine fluidic apparatus are also disclosed, including the use of fusion bonding of non-conducting substrates, high-aspect ratio etching techniques, and anisotropic etching and refill techniques, preferably utilizing chevron-shaped slit openings to fabricate microtube sections.