625 results about "Ph control" patented technology

A method is given for treating a subterranean formation penetrated by a wellbore with a viscosified fluid. The fluid contains a solid hydrolysable polyacid that upon dissolution and hydrolysis releases an acid that is a breaker for the viscosifying system. Suitable solid hydrolysable polyacids include polylactic acid and polyglycolic acid. The fluid also contains a pH control agent, present in an amount sufficient to neutralize any acid present in the solid hydrolysable polyacid before the injection and to neutralize any acid generated by the solid hydrolysable polyacid during the injection, so that the acid breaker is not available to break the fluid during the injection. In one embodiment the viscosifier is a viscoelastic surfactant fluid system and the solid hydrolysable polyacid is of a size selected to be a fluid loss additive, for example in fracturing or gravel packing. In another embodiment, the solid hydrolysable polyacid is used in particles sufficiently small that they enter the pores of the formation. In either case, the viscosifier is broken after the solid releases more acid than can be neutralized by the pH control agent.

Provided herein is a pad for treating eye conditions comprising a multipart container having an impermeable outer membrane sized to fit generally within the peri-orbital region and sufficiently flexible to mold to the eye; a first chemical in a first storage area in the multipart container; a second chemical in a second storage area in the multipart container, the first and second chemicals selected to have an exothermic reaction when mixed for producing a temperature suitable for treating eye conditions, the exothermic reaction providing the suitable temperature for a period of time suitable for treating eye conditions; and an inner membrane for initially separating the first and second chemicals, the inner membrane being renderable permeable, without causing the impermeable outer membrane to become permeable, to permit mixing the first and second chemicals to cause the exothermic reaction. This multipart container is covered with a soft, non-abrasive, lint-free material which is presoaked in a pH controlled antibacterial soap with or without an antibiotic.

A container has an impermeable outer membrane sized to fit generally within the peri-orbital region and sufficiently flexible to mold to the structure of the closed eye. Heat which is generated by an exothermic reaction inside the container, which provides steady-state heat to the eyelids. A soft, non-abrasive, lint-free material is presoaked in a pH controlled (preferably antibacterial and hypoallergenic) detergent, with or without an ophthalmic antibiotic solution. The compress may also have a handle which makes holding and maneuvering the compress more feasible, while protecting the user's fingers from the heat, and preventing the contamination of the compress by the fingers. The compress may be packed in a watertight, sterile wrapper which will prevent drying of the detergent solution. Other embodiments are also described and claimed.

The invention provides a method for large-scale production of a polypeptide, such as a Factor VII or Factor VIIa polypeptide, in eukaryote cells, such as mammalian cells, contained in a culture liquid, said method comprising: monitoring the concentration of dissolved CO2 in the culture liquid, and constantly or intermittently sparging atmospheric air through the culture liquid, wherein the sparging rate of the air is controlled in relation to the monitored concentration of dissolved CO2 in the culture liquid. The method reduces or eliminates the use of bases while providing an excellent pH control. The invention also provides a culture vessel suitable for the methods.

The present invention provides a variety of microscale bioreactors (microfermentors) and microscale bioreactor arrays for use in culturing cells. The microfermentors include a vessel for culturing cells and means for providing oxygen to the interior of the vessel at a concentration sufficient to support cell growth, e.g., growth of bacterial cells. Depending on the embodiment, the microfermentor vessel may have various interior volumes less than approximately 1 ml. The microfermentors may include an aeration membrane and optionally a variety of sensing devices. The invention further provides a chamber to contain the microfermentors and microfermentor arrays and to provide environmental control. Certain of the microfermentors include a second chamber that may be used, e.g., to provide oxygen, nutrients, pH control, etc., to the culture vessel and / or to remove metabolites, etc. Various methods of using the microfermentors, e.g., to select optimum cell strains or bioprocess parameters are provided. The invention provides microreactors having a variety of different designs, some of which incorporate active stirring and / or have the capability to operate in batch or fed-batch mode. The invention further provides an apparatus and methods for simultaneous operation of a plurality of microreactors, with monitoring of the individual microreactors during a run. The invention further provides methods of performing gene expression analysis on cells cultured in microreactors.

The present invention is directed to a homogeneous, thermoreversible gel comprising carrageenan wherein the carrageenan has a viscosity of less than 10 cP at 75° C. when measured in a 0.10 molar aqueous sodium chloride solution containing 1.5% by weight of the carrageenan based on the weight of all components in the solution, and optionally at least one of a plasticizer, a second film former, a bulking agent, and a pH controlling agent, wherein the gel has a solids content of at least 40%. The present invention is also directed to processes for the preparation thereof, as well as to variety of products containing the gel including edible products, soft capsules, hard capsules and solid forms encapsulating powders, tablets, caplets, etc.