24626 results about "Urea" patented technology

Wood preservative compositions are disclosed. Treatment of lumber, plywood, and other wood products with a novel composition comprising the boron source composition, a melamine binder resin, and a urea casein activator resin protects lumber, plywood, and other wood products from attack by termites, fungi, fire and flame. The preservative can be formed by combining a source of boron such as boric acid and the water-soluble salts thereof, a melamine binder resin, and a urea casein resin. A wood preservative is characterized by a weight ratio of the urea casing activator resin to the melamine binder resin ranging from about 1:20 to 1:4 and a weight ratio of the boron source composition to the melamine binder resin ranging from about 1.3:1 to 9.6:1.

The invention relates to libraries of synthetic test compound attached to separate phase synthesis supports. In particular, the invention relates to libraries of synthetic test compound attached to separate phase synthesis supports that also contain coding molecules that encode the structure of the synthetic test compound. The molecules may be polymers or multiple nonpolymeric molecules. Each of the solid phase synthesis support beads contains a single type of synthetic test compound. The synthetic test compound can have backbone structures with linkages such as amide, urea, carbamate (i.e., urethane), ester, amino, sulfide, disulfide, or carbon-carbon, such as alkane and alkene, or any combination thereof. Examples of subunits suited for the different linkage chemistries are provided. The synthetic test compound can also be molecular scaffolds, such as derivatives of monocyclic of bicyclic carbohydrates, steroids, sugars, heterocyclic structures, polyaromatic structures, or other structures capable of acting as a scaffolding. Examples of suitable molecular scaffolds are provided. The invention also relates to methods of synthesizing such libraries and the use of such libraries to identify and characterize molecules of interest from among the library of synthetic test compound.

Pharmaceutical, cosmetic and cosmeceutical foamable compositions for topical application, containing, as an active ingredient, urea and / or a derivative thereof, processes of manufacturing these compositions and uses of these compositions in the treatment of various dermatological conditions such as, for example, conditions associated with dry skin and / or scalp.

Apparatus and method for determining at least one parameter, e. g., concentration, of at least one analyte, e. g., urea, of a biological sample, e. g., urine. A biological sample particularly suitable for the apparatus and method of this invention is urine. In general, spectroscopic measurements can be used to quantify the concentrations of one or more analytes in a biological sample. In order to obtain concentration values of certain analytes, such as hemoglobin and bilirubin, visible light absorption spectroscopy can be used. In order to obtain concentration values of other analytes, such as urea, creatinine, glucose, ketones, and protein, infrared light absorption spectroscopy can be used. The apparatus and method of this invention utilize one or more mathematical techniques to improve the accuracy of measurement of parameters of analytes in a biological sample. The invention also provides an apparatus and method for measuring the refractive index of a sample of biological fluid while making spectroscopic measurements substantially simultaneously.

A pharmaceutical composition for transdermal administration of a hormone (e.g., testosterone), which includes urea and / or a derivative thereof as a penetration enhancer, and methods utilizing same for treating medical conditions in which elevating a hormone serum level is beneficial are disclosed.

The present invention provides biodegradable polymer particle delivery compositions for delivery of macromolecular biologics, for example in crystal form, based on polymers, such as polyester amide (PEA), polyester urethane (PEUR), and polyester urea (PEU) polymers, which contain amino acids in the polymer. The polymer particle delivery compositions can be formulated either as a liquid dispersion or a lyophilized powder of polymer particles containing bound water molecules with the macromolecular biologics, for example insulin, dispersed in the particles. Bioactive agents, such as drugs, polypeptides, and polynucleotides can also be delivered by using particles sized for local, oral, mucosal or circulatory delivery. Methods of delivering a macromolecular biologic with substantial native activity to a subject, for example orally, are also included.

This invention relates to the use of a group of aryl ureas in treating raf mediated diseases, and pharmaceutical compositions for use in such therapy.

The present invention includes apparatuses and methods for mitigating the effects of foreign interferents on analyte measurements. The present invention comprises several interferent mitigation steps. Examples include sample cleaning procedures, detection of the presence of interferents, determination of the identity of interferents, and modification or selection of a multivariate calibration model to mitigate the effects of one or more interferents on analyte measurements. The interferent mitigation steps of the present invention can be applied individually, and in some embodiments can be applied in combination. Some examples of relevant analyte measurements include the noninvasive determination of the presence or concentration of alcohol, glucose, urea, byproducts of alcohol metabolism, and substances of abuse.

An exhaust aftertreatment system comprises an injector for injecting urea water into an exhaust duct, and a denitration catalyst disposed downstream of the injector with respect to a flow of exhaust gas. The exhaust aftertreatment system reduces nitrogen oxides in the exhaust gas by the denitration catalyst while using ammonia produced from the urea water injected from the injector. The urea water is injected along a direction of the flow of the exhaust gas within the exhaust duct, and a porous plate is disposed in multiple stages in a space of the exhaust duct such that droplets of the injected urea water impinge against the porous plate before reaching a wall surface of the exhaust duct. A surface of the porous plate subjected to the impingement of the droplets is arranged to face downstream with respect to the flow of the exhaust gas. Deposition of the urea water is prevented by causing film boiling when the droplets impinge against the porous plate, and the urea water reflected by the porous plate is uniformly dispersed into the exhaust gas. Thus, the urea water is uniformly dispersed into the exhaust gas without increasing a pressure loss of the exhaust gas. The urea water is prevented from depositing on the wall surface and producing a precipitate in the form of a solid.

The invention relates to an alcohol-free cosmetic or pharmaceutical foam composition comprising water, a hydrophobic solvent, a surface-active agent, a gelling agent, an active component selected from the group of urea, hydroxy acid and a therapeutic enhancer and a propellant. The foam further comprises active agents and excipients with therapeutic properties having enhanced skin penetration.

A reductant dosing control system, for use in a Selective Catalytic Reduction (SCR) system of a motor vehicle includes an input receiving a NOx feedback signal from an NOx sensor provided to the SCR system. A base dosing module calculates a required quantity of reductant to inject in front of a SCR catalyst of the SCR system based on the NOx feedback signal. The SCR catalyst has ammonia storage properties. An output signals a reductant metering mechanism to periodically or continuously inject excess reductant based on the required quantity of reductant.

The present invention relates to biocompatible, biodegradable polyurethane / urea polymeric compositions that are capable of in-vivo curing with low heat generation to form materials suitable for use in scaffolds in tissue engineering applications such as bone and cartilage repair. The polymers are desirably flowable and injectable and can support living biological components to aid in the healing process. They may be cured ex-vivo for invasive surgical repair methods, or alternatively utilized for relatively non-invasive surgical repair methods such as by arthroscope. The invention also relates to prepolymers useful in the preparation of the polymeric compositions, and to methods of treatment of damaged tissue using the polymers of the invention.

The invention belongs to the technical field of preparation of a carbon nano material, and particularly relates to a method for preparing a carbon dot having a high fluorescent quantum yield from citric acid and different nitrogen-containing molecules. The method comprises the following steps: weighing 1-10 mmol of solid citric acid, and dissolving in 10 ml of deionized water; weighing 1-10 mmol of ethylenediamine, ethylamine, propylamine, butanediamine, n-hexylamine, p-phenylene diamine or urea, adding into the citric acid solution, and uniformly stirring; transferring the solution into a hydrothermal or high-pressure microwave reaction kettle, reacting under hydrothermal or microwave conditions, and naturally cooling the reaction kettle to room temperature, thus obtaining a yellow or brown carbon dot water solution; and finally, purifying the carbon dot water solution, evaporating, and drying to obtain pure carbon dot solid powder. The carbon dot solution can send out bright blue fluorescence under the irradiation of a handheld ultraviolet lamp. The invention has wide application prospects in the fields of biological imaging, fluorescent printing and the like.

This patent describes technology for generating ammonia from urea. The method is based on the hydrolysis of an aqueous solution of urea and / or biuret by heating under pressure to form a mixture of ammonia, carbon dioxide and water. The gas mixtures produced are useful for supplying ammonia at controlled pressure and rate of flow for many industrial applications without the risks and hazards associated with the transportation and on-site storage of ammonia, thereby providing a significant safety advantage over present industrial practice.

A method is presented for estimating an amount of ammonia stored in a urea-based SCR catalyst based on a dynamic model of the catalyst. The model takes into account chemical and physical properties of the catalyst, such as catalyst volume, the number of available ammonia storage cites, adsorption and desorption dynamics, as well as sulfur poisoning, thermal aging, and different catalyst operating temperatures, and generates the estimate based on a measured or estimated amount of NOx in an exhaust gas mixture upstream of the catalyst, an amount of reductant injected into the catalyst to facilitate NOx reduction, and on a measured value of NOx in an exhaust gas mixture downstream of the catalyst. The estimated ammonia storage amount is then used to control the amount of reductant injected into the catalyst to maintain desired ammonia storage amount such that maximum NOx conversion efficiency coupled with minimum ammonia slip are achieved.

The present invention provides a polyurethane or polyurethane / urea composition which has a tensile strength greater than 10 MPa, a modulus of elasticity greater than 400 MPa and an elongation at break greater than 30% at a temperature of between 0° C. and 60° C. and at a relative humidity of between 0% and 100%.The invention further provides uses of the compositions of the invention in biomedical vascular stents, an orthopaedic implant, a drug delivery coating or in tissue engineering.

This invention relates to biocompatible, biodegradable thermoplastic polyurethane or polyurethane / ureas comprising isocyanate, polyol and a conventional chain extender and / or a chain extender having a hydrolysable linking group and their use in tissue engineering and repair applications, particularly as stents and stent coating.

The present invention provides synthetic vaccines against a variety of pathogenic organisms and tumor cells in humans and other mammals based on biodegradable polymers containing polyester amide (PEA), polyester urethane (PEUR), and polyester urea (PEU) and immunostimulatory adjuvants. The vaccines can be formulated as a liquid dispersion of polymer particles or molecules in which are dispersed an immunostimulatory adjuvant, such as a TLR agonist, and whole protein or peptidic antigens containing MHC class I or class II epitopes derived from organism or tumor cell proteins. Methods of inducing an immune response via intracellular mechanisms to the pathogenic organism or tumor cells specific for the antigen in the invention compositions are also included.

There are provided a reductant supply device and a control method for the reductant supply device, which can prevent heat damage of a reductant injection valve, and also prevent crystallization of urea solution due to excessive cooling of the solution reductant.The reductant supply device which is used in an exhaust gas purification device that injects and supplies, as a reductant, a urea solution to an exhaust gas upstream side of a reduction catalyst disposed in an exhaust gas passage of an internal combustion engine, and that reduces and purifies nitrogen oxides contained in exhaust gas using the reduction catalyst, the reductant supply device having a reductant injection valve that is fixed to an exhaust pipe on the exhaust gas upstream side of the reduction catalyst, includes: a cooling water circulation passage that circulates at least part of cooling water of the internal combustion engine to cool the reductant injection valve; flow rate control means for adjusting a flow rate of cooling water flowing through the cooling water circulation passage; temperature detection means for detecting a temperature of the reductant injection valve; and control means for controlling the flow rate control means based on the temperature of the reductant injection valve.

An exhaust emission control device has a particulate filter 5 and a selective reduction catalyst 6 arranged side by side. An S-shaped communication passage 9 is arranged for introduction of exhaust gas 3 from a rear end of the filter 5 to a front end of the adjacent catalyst 6 in a forward fold-back manner and with a urea water addition injector 11 arranged midway of the passage 9. In order to satisfactorily disperse the urea water with enhanced mixing with the exhaust gas 3 even if the flow rate is increased, slits 12 are formed in circumferentially spaced positions on a rear end of a mixing pipe 9B constituting an upstream portion of the communication passage 9 so as to introduce the exhaust gas 3. A downstream end 9a of a gas gathering chamber 9A is connected to the rear end of the mixing pipe 9B such that the slits 12 are encased and the rear end of the mixing pipe 9B is closed.

Dental bleaching compositions are made with a bleaching agent and a stable radiant-energy absorbing compound that acts as a bleaching agent activator. The dental bleaching compositions of the present invention can be one-part, pre-mixed compositions that do not require mixing at the time of treating a patient's teeth but which remain stable over time. The bleaching agent may consist of hydrogen peroxide, either in aqueous form or complexed with urea (carbamide peroxide) or sodium perborate. The bleaching agent activator includes hydrocarbons that are stable in the presence of the bleaching agent, which do not prematurely accelerate liberation of the bleaching agent, but which allow for selective activation of the bleaching agent by irradiation of the bleaching composition with radiant energy. The bleaching composition may optionally include a neutralizing agent to adjust the pH, a carrier to help provide proper consistency and potency, and a stabilizing agent to maintain maximum potency of the bleaching agent over time. The bleaching composition may also include a thickening agent to achieve a selected viscosity. The dental bleaching compositions may be adapted to be loaded into and delivered from a syringe.

A reductant dosing control system, for use in a Selective Catalytic Reduction (SCR) system of a motor vehicle includes an input receiving a NOx feedback signal from an NOx sensor provided to the SCR system. A base dosing module calculates a required quantity of reductant to inject in front of a SCR catalyst of the SCR system based on the NOx feedback signal. The SCR catalyst has ammonia storage properties. An output signals a reductant metering mechanism to periodically or continuously inject excess reductant based on the required quantity of reductant.

An exhaust emission purifying apparatus has a NOx reduction catalytic converter in an exhaust passage of an engine, for purifying nitrogen oxides in the exhaust gas by reduction with urea aqueous solution; an injection nozzle injecting the urea solution toward an exhaust upstream side of the converter in the exhaust passage; and fins disposed on an exhaust upstream side of an injection position of the urea solution in the injection nozzle, for generating a spiral swirling flow of the gas swirling about a center corresponding to the central axis of an exhaust pipe. The swirling flow generated in the exhaust gas prior to the injection-supply of the urea aqueous solution promotes mixing of the solution with the gas to thereby promote the hydrolysis of the urea solution. And the exhaust gas and ammonia generated from the urea solution are uniformly mixed together.

Topical dermatological compositions comprising urea as an active ingredient, a vegetable oil or a derivative thereof, water, and conventional excipients. These compositions are used for topical medical applications, particularly to treat various skin disorders.

A method is provided for producing ammonia (NH3) and introducing the produced ammonia (NH3) into an exhaust gas stream as a reduction means for selectively catalytically reducing nitrogen oxides contained in the exhaust gas stream, which is an exhaust stream generated by the combustion process of a motor, a gas turbine, or a burner. The method comprises feeding dry urea from a supply container in a controlled amount to reactor and subjecting the dry urea in the reactor to a sufficiently rapid thermal treatment such that a gas mixture comprising the reaction products of ammonia (NH3) and isocyanic acid (HCNO) is created. Also, the method comprises immediately catalytically treating the thus produced gas mixture in the presence of water such that the isocyanic acid (HCNO) resulting from the rapid thermal treatment is converted, via quantitative hydrolysis treatment, into ammonia (NH3) and carbon dioxide (CO2).

A selective catalytic reduction (SCR) catalyst control system and method for an engine is disclosed. Urea injection to an SCR catalyst is determined based on an SCR catalyst model, which determines a value of stored NH3 in the SCR catalyst based on the NOx engine emission value, the SCR catalyst temperature, the quantity of urea supplied to the SCR catalyst and a pre-determined efficiency of conversion of NOx gases. A target value of stored NH3 and the value of stored NH3 in the SCR catalyst is then used to determine a stored NH3 differential, which is then used to calculate urea injection.

The invention discloses a method for preparing salvianolic acid A by catalytically converting salvianolic acid B. The method is characterized in that the converted raw material is a salvia miltiorrhiza aqueous extract (salvianolic acid B=>50%) primarily purified through combined chromatography; the concentration of the raw material salvianolic acid B is 0.5-2%; urea is taken as the catalyst; the mole ratio of urea to the salvianolic acid B is 0.3-0.7; the conversion reaction temperature is 100-125 DEG C; and the reaction time is 3-6 hours. The method has the following beneficial effects: urea is taken as the catalyst, thus greatly shortening the time for which the salvianolic acid B is in easily destroyed state and remarkably increasing the yield of the salvianolic acid A; the primarily purified salvia miltiorrhiza extract is taken as the converted raw material, thus not only removing the metal ions which are not beneficial to conversion but also removing most colloid-like impurities and frontal impurities which are not beneficial to following separation of the salvianolic acid; and the directional conversion rate of the salvianolic acid B to the salvianolic acid A prepared by the method is not less than 10% and even reaches 60%.