223 results about "Active surface area" patented technology

An electrosurgical generator which provides a constant power output particularly suited for cutting arc formation at an active electrode which exhibits a dynamic active surface area of varying geometry. Essentially constant power-based control is achieved through the utilization of a d.c. link voltage the level of which functions to establish the amplitude of the output of an RF resonant inverter. A dual loop feedback control is described wherein output power based control signals are slowly introduced at low gain, while link voltage based controls are comparatively rapidly applied. Enhanced development of a controlling d.c. link voltage is achieved through the utilization of an input network incorporating a power factor correction stage.

A touch screen 1111 having an active surface area 1112 which extends in three physical dimensions (x-, y- and z-dimensions) is provided. In the figure the active surface area has an U-shaped form. When a user slides his finger over the active surface area the tactile feedback gives him information about the position of the finger. The touch screen is activated when the active surface area senses a certain pressure from the finger. The use of the touch screen is facilitated especially when the user is on the move or when the touch screen is out of sight. Such use is common when operating hand-held terminals.

The present invention discloses a pharmaceutical-grade ferric organic compounds, including ferric citrate, which are soluble over a wider range of pH, and which have a large active surface area. A manufacturing and quality control process for making a pharmaceutical-grade ferric citrate that consistently complies with the established Manufacture Release Specification is also disclosed. The pharmaceutical-grade ferric organic compounds are suitable for treating disorders characterized by elevated serum phosphate levels.

An electrode with large active surface area is made by winding a Ti-fiber tow around a rectangular Ti-plate, and an electrocatalytic coating of three layers is applied. A precoat comprising a mixture of iridium dioxide and tantalum pentoxide is applied first, using a solution of the corresponding chloride salts in hydrochloric acid with some nitric acid added to inhibit corrosion of the metal. A sealing coat is then applied, comprising tin dioxide doped with antimony, in order to improve adhesion of the final oxide coat to the precoat. The third and final coat comprises particles of titanium dioxide doped with niobium in the +4 oxidation cemented with titanium dioxide that is doped with antimony. Anodes of this description are preferably assembled together with corrosion resistant cathodes in an alternating sequence, with a plastic coated fiber glass mesh placed between the anodes and cathodes to prevent short circuiting. When a sufficiently large voltage is applied across the cell, organic substances dissolved in the electrolyte will be oxidized.

The present invention provides electrodes comprised of metal-coated vertically aligned carbon nanofibers. Arrays of vertically aligned carbon nanofibers provide highly accessible, high density templates having large electrochemically active surface areas that may be modified to further increase the surface area of the nanofibers. The methods of the present invention involve functionalizing the surface of the nanofibers and coating the functionalized surface with metal using electroless deposition. The resulting metal-coated nanofibers form highly stable and highly reproducible electrodes having very high surface areas. The electrodes of the present invention are expected to be useful in a variety of applications, including high-density energy storage, i.e., supercapacitors and fuel cells.

The present invention provides cobaltosic oxide hierarchical structure nano array materials and a preparation method thereof, and an application of cobaltosic oxide hierarchical structure nano array materials. In a closed high temperature and high pressure reactor, redistilled water is taken as reaction solvent, cobalt salt, ammonium fluoride and urea are added into the reaction solvent for uniform mixing, and a reaction system is heated to generate a high-pressure environment to prepare cobaltous hydroxide precursor nanowire materials; then redistilled water is taken as reaction solvent, 2-methylimidazole is added into the reaction solvent, the cobaltous hydroxide precursor loaded on carbon cloth is immersed in the solution, the cobaltous hydroxide is taken as a cobalt source, the reaction system is heated and the reaction time is controlled to control a ZIF67 nucleation rate so as to prepare a cobalt-based metal organic framework (ZIF67) array; and finally, calcining decomposition ofthe cobalt-based metal organic framework (ZIF67) array is performed to obtain a cobaltosic oxide hierarchical structure. The product purity is high, the dispersibility is good, the controllability isgood, the production cost is low, the reproducibility is good, the cobaltosic oxide hierarchical structure nano array materials have cycling stability and large active surface area, and have a potential application value at the aspect of supercapacitors.

The invention relates to processes for the production and elements (components) with a nanostructure (2; 4, 4a) for improving the optical behavior of components and devices and/or for improving the behavior of sensors by enlarging the active surface area. The nanostructure (2) is produced in a self-masking fashion by means of RIE etching and its material composition can be modified and it can be provided with suitable cover layers.

Catalytic layers for use in the electrodes of fuel cells including a non-noble metal substrate layer coated with one or a few monolayers of noble metal, such as Pt. These thin, highly porous structures with large catalytically active surface areas, should exhibit a significantly higher power output per mg of Pt and per cm² of the membrane than the current Polymer Electrolyte Fuel Cells catalytic layers.

The invention provides a ternary MOF nanosheet array material as well as a preparation method and application thereof, in a high-temperature high-pressure reaction kettle, methanol is used as a reaction solvent, a nickel salt, an iron salt, a cobalt salt and organic ligand 2-methylimidazole are added according to a ratio for mixing evenly, and a high-pressure environment is generated by heating the reaction system to prepare the ternary MOF nanosheet array material. Compared with the prior art, the product obtained by the preparation method disclosed by the invention is high in purity, good indispersibility, good in reproducibility and low in production cost, and can be controlled, and a stable and uniform morphology structure is formed by controlling the dosage and concentration of the raw materials and the reaction temperature and time. The prepared ternary MOF nanosheet array material grows on foamed nickel and can be directly used as an electrode material, so that long cycling stability and large active surface area are achieved, and the ternary MOF nanosheet array material has a potential application value in the aspect of oxygen evolution reaction.

The invention relates to a macroporous noble metal-loaded catalyst with metal oxide as a carrier and for purifying soot exhausted by diesel and a preparation method thereof. The invention firstly provides an oxidation catalyst for combustion of soot particles exhausted by diesel vehicles. The catalyst is obtained by taking the simple metal oxide or composite metal oxide which contains more than one of rare earth metals, transition metals and alkaline metals and has three-dimensionally ordered macroporous structure as a carrier and loading the noble metal active ingredient, wherein the simple metal oxide is any one of metallic elements; the composite metal oxide is perovskite or perovskite-like composite metal oxide; the noble metal active ingredient is gold; and the mean size of the macropores in the carrier is 50nm-1mu m. The catalyst conduces to diffusion of the soot particles in the pore canal, improves the use ratio of the active surface area and greatly reduces the combustion temperature of the soot particles. The invention also provides the preparation method of the catalyst.

The invention discloses a carbon-containing metal catalyst, a preparation method and an application thereof. The catalyst uses carbon fiber material as a carrier, and uses sodium borohydride, methanol or glycol as a reducing agent. One or several of chloroplatinic acid, chloroauric acid, and other metal precursors are mixed and then reduced to obtain a metal/carbon nanofiber catalyst for fuel cells, preferably with a metal loading amount being 10-60 wt %. The catalyst is high in initially electrochemically active surface area, and relatively small in current density attenuation during a 120-minute chronoamperometry test, has a current density higher than that of present commercial platinum catalyst/XC72R (40 %) during a whole electrochemical chronoamperometry test, and shows relatively high electrochemical activity, relatively high current density and relatively superior electrochemical stability. The catalyst show extremely high resistance to carbon monoxide toxicity.

An aircraft taxi path guidance and display system is provided. The aircraft taxi path guidance and display system includes or cooperates with at least one source of aircraft status data, and a source of airport feature data associated with an airport field. The aircraft taxi path guidance and display system includes a processor operationally coupled to the source of aircraft status data and to the source of airport feature data. In response to aircraft status data and airport feature data, the processor predicts undesired deviations from an active surface area (e.g., an excursion). The processor generates corrective action associated with the excursion, and displays symbology that is graphically representative of the corrective action.

The invention discloses a composite nanostructure based on a three-dimensional porous transition metal carbide Ti3C2MXene and a general preparation method thereof, and belongs to the field of nanomaterials. The three-dimensional composite structure is composed of a three-dimensional porous Mxene-supported inorganic nanostructure, and has a honeycomb hierarchical porous structure. A precursor of atwo-dimensional transition metal carbide and a metal-organic framework compound is subjected to high-temperature pyrolysis or a chemical reaction in an inert or reactive atmosphere to prepare the composite nanostructure with a controllable size. According to the composite nanostructure, stacking of MXene itself is inhibited, an active surface area, porosity, and ion permeability of MXene are increased, and thereby a surface interface of MXene is efficiently used. At the same time, introduction of the metal-organic framework compound realizes uniform and stable compounding of the three-dimensional porous MXene and an inorganic nanomaterial, the fundamental difficult problem that plagues exerting and application of inorganic nanomaterial performance is solved, and the composite nanostructurehas wide application prospects in the fields such as catalysis, energy, photo-electricity, space technology, and military industry.

The invention discloses a selective hydrogenation catalyst for producing biodiesel and a preparation method and application of the selective hydrogenation catalyst. The selective hydrogenation catalyst comprises a carrier and a main metal active ingredient loaded on the carrier, the main metal active ingredient accounts for 5-30% of the catalyst in weight and is one of or a combination of oxides containing Co, Mo, Ni and W, and the carrier is composed of, by weight, 1-8% of a molecular sieved, 25-65% of amorphous sial, 30-65% of alumina and 2-10% of a graphene auxiliary. The preparation method includes: disposing the carrier in a metal salt solution containing Co, Mo, Ni or/and W for soaking for 4-20 h to obtain a soaked carrier; freeze-drying and then calcining the soaked carrier to obtain the selective hydrogenation catalyst. With same carrying capacity of the carrier, active surface area represented by the carrier is large, the selective hydrogenation catalyst has more active sites, reaction temperature is lowered, and hydrogenation performance is improved.

The invention relates to methods and devices comprising a nanostructure (2;4,4a) for improving the optical behavior of components and apparatuses and/or improving the behavior of sensors by increasing the active surface area. The nanostructure (2) is produced by means of a special RIE etching process, can be modified regarding the composition of the materials thereof, and can be provided with adequate coatings. The amount of material used for the base layer (3) can be reduced by supplying a buffer layer (406). Many applications are disclosed.

A silicon-based solid oxide fuel cell (SOFC) with high surface area density in a limited volume is provided. The structure consists of a corrugated nano-thin film electrolyte and a silicon supportive layer on a two-stage silicon wafer through-hole to maximize the electrochemically active surface area within a given volume. The silicon supportive layer is done by boron-etch stop technique with diffusion doping. The fabrication of two-stage wafer through hole combines deep reactive ionic etching (DRIE) and KOH wet etching of silicon for a wafer through hole containing two difference sizes. By these design and fabrication methods, the absolute electrochemically active area can be as high as five times of that of the projected area.

A fuel cell membrane-electrode assembly having a fuel electrode and an oxidant electrode has a non-supported-catalyst containing catalyst layer that contains a metal catalyst nanoparticle of 0.3 nm to 100 nm in primary particle diameter that is not supported on a support, and an electrochemically active surface area of the metal catalyst nanoparticle is 10 m²/g to 150 m²/g, and a layer thickness of the non-supported-catalyst containing catalyst layer is less than or equal to 10 μm.

Layered catalyst structures for fuel cells, particularly for a Proton Exchange Membrane Fuel Cell (PEMFC), are produced by a reactive spray deposition technology process. The catalyst layers so produced contain particles sized between 1 and 15 nm and clusters of such particles of a catalyst selected from the group consisting of platinum, platinum alloys with transition metals, mixtures thereof and non-noble metals. The catalyst layers without an electrically conducting supporting medium exhibit dendritic microstructure, providing high electrochemically active surface area and electron conductivity at ultra-low catalyst loading. The catalyst layers deposited on an electrically conducting medium, such as carbon, exhibit three-dimensional functional grading, which provides efficient utilization as a catalyst, high PEMFC performance at the low catalyst loading, and minimized limitations caused by reactant diffusion and activation. The catalytic layers may be produced by a single-run deposition method.

The invention relates to a composite carbon fiber-loaded metal catalyst as well as a preparation method and application thereof. The composite carbon fiber-loaded metal catalyst is high in graphitization degree, good in catalyst metal particle dispersion performance and excellent in catalytic performance and is prepared by adopting a transitional metal oxide as a graphitization enhancer of a carbon material and a metal dispersion loading induction agent. The prepared composite carbon fiber material loaded with the transitional metal oxide is catalyzed through the transitional metal oxide under the high temperature condition to obtain a carbon material with a high graphitization degree, and the transitional metal oxide composite carbon fiber material is used as a catalyst carrier to be reduced by a reduction agent. The catalyst is high in initial electrochemical activity surface area and good in duration, and after the catalyst is cycled for 4500 times, the electrochemical active surface area sill can be maintained at 54 percent. The current density attenuation is reduced in a timing current-method electrochemical test of 120 minutes, the electrochemical activity is high, the current density is high, and the duration is excellent.