text:
Nanostructured oxide and hydroxide and methods for their synthesis
C01G53/04 - Oxides; Hydroxides
C01B13/36 - by precipitation reactions in solutions
C01B13/34 - by oxidation or hydrolysis of sprayed or atomised solutions
(57) Abstract:
The invention relates to the production of nanostructured materials by chemical means. The method includes spraying of the reagent solution into the previous solution for sediment nanostructured oxide or hydroxide. The precipitate is then subjected to heat treatment followed by sonication or treatment with ultrasound with subsequent heat treatment. This method gives nanostructured alloy and unalloyed Nickel hydroxide, manganese dioxide and yttrium-stabilized zirconium oxide. Can be obtained unusual morphological superstructure, including clearly distinguishable cylinders or nanorods, as well as new patterns for Nickel hydroxide and manganese dioxide, including Assembly of nanostructured fibers, Assembly, nanostructured fibers and agglomerates of nanostructured particles and Assembly of nanostructured nanostructured fibers and particles. These new structures have a high rate of percolation and high density of active sites, which makes them particularly suitable for the manufacture of catalysts. 8 C. and 58 C.p. f-crystals, 1 tab., 17 ill.
The invention relates to the synthesis of nanostructured materials Henichesk the Kimi ways, thereby to obtain materials with controlled morphology, phases and microstructures, including a new class of fibrous microstructures, which combines a high density of chemically active sites with a better rate of percolation of liquids.
Materials with small-scale microstructure, have a unique and technologically attractive properties, as shown by work on bathroomvanities metals, alloys and composite materials reach a grain size of about several micrometers (μm). However, recent research has focused on the reduction of grain size with micrometer interval to the nanometer range. A characteristic feature of such nanostructured materials is the large fraction of atoms (up to 50%), located on the borders of the grains or particles. Fig.1, where the white circles denote the edge atoms of grain, and the shaded circles denote the inner atoms schematically illustrates this phenomenon. A large fraction of atoms located at the boundary surfaces, which is important for creating a high density of potential centers for catalytic and electrochemical reactions. Nanostructured materials that are here to mA and in many cases superior chemical and physical properties compared to their equivalents of the same chemical composition, but with grains of micron size.
Nanostructured powders synthesized previously by chemical methods from aqueous solutions. Typical previously known synthesis procedure consists of three consecutive stages: (1) preparation of an aqueous starting solution of the mixture of metal salts, (2) reductive decomposition of the initial solution to obtain a colloidal suspension of the desired phase of the final product, and (3) highlighting powder end product of multiple washing and drying. The resulting dried powder products have the form of loosely agglomerated nanoparticles. The solutions of the chlorides of the metals can be recovered by trialkylborane sodium for nanostructured powders of Nickel or iron, and mixed solutions of the chlorides of the metals can be recovered for nanostructured powders M50 steel, AIN/BN, Ni, CR/CR3WITH2and WC/Co.
Synthesis of oxides and hydroxides in nanostructured form simplifies the manufacture of components and devices with modified and/or superior properties. An additional advantage of reducing the grain size to the nanoscale dimensions is the elimination of large voids at grain boundaries, which often bring harmful with the set of superplastic strain at relatively low temperatures and pressures, as described in the examples in Nanostructured Materials, Vol. 1, 1992, is essential when seteobraznyh the formation of brittle ceramic and intermetallic components. When applying industrial coatings, such as thermal coatings, restoration to the nanoscale is highly effective to increase thermal resistance. In dense ceramic coatings and nanostructured materials capable of providing high hardness combined with good resistance to fracture and corrosion resistance.
Materials with high specific surface nanoscale dimensions are of particular interest for applications where a crucial role is played by the called active centers of chemical reactions. When applying the catalyst for important large contact surface for the oxidation and restore the environment, and therefore the reduction of the catalytic material to the nanoscale, clearly gives a considerable advantage. The application of catalysts include pollution control, such as disposal of nuclear waste, water treatment, demercurization, cleaning of particulate and air filtration and catalysis for the synthetic purposes, such as molecular sieves, refining and others. About the ora lack of modern nanostructured materials is the tendency of particles to form agglomerates, in which the space of the pores between the particles becomes comparable to the particle size, that is, where the space of the pores between the particles has nanoscale dimensions. Such small pore sizes limit the rate of percolation of active substances in the agglomerates and through them.
Another field of application of nanostructured materials are rechargeable batteries and fuel cells, where high specific surface area nanostructured materials and increases the speed of interaction between the active material with the environment. For example, rechargeable batteries with high energy density necessary to sustain a high current pulses in the conditions of charging and discharging requires maximum contact between the electrode and the electrolyte to achieve high-density transport of ions and electrons. Active nanostructured materials with their high density of regulated surface defects meet these requirements, thus providing ways to optimize high energy batteries.
The Nickel electrode is particularly widespread and determines the spread in rechargeable batteries, as it is usually the limiting capacity of the electrodes in Ni-Cd, Ni can be obtained by cathodic deposition from a solution and deposition from concentrated alkali. Traditional Nickel electrodes made of porous Nickel plates, made from powder, carbonyl Nickel, Ni(CO)4. Porosity is usually limited to 80%, and the volume occupied by the leaf and the plate is about 20%. This record is then either chemically or electrochemically impregnated with the active material. The Japanese were pioneers in the development of high-performance spherical Nickel hydroxide (Japanese Tanaka) for use in foamed or processed Nickel electrodes of the interwoven fibers. These substrates are highly porous (about 95%), so that a large amount of active material can be loaded into the electrodes. This represents a radical departure from the traditional use of the treated electrodes neklikabelno type requiring complicated manufacturing processes for the chemical or electrochemical deposition of the active material inside the porosity of the plate.
Materials of Nickel hydroxide is still not received in nanostructured form. In modern practice, the Nickel hydroxide micron size receive chemical deposition and electrolytic deposition. Work on materials of micron scale based on the Nickel hydroxide is Institute in the Nickel electrodes typically use phase due to its stability in the cyclic process of charge and discharge. However, a hydroxide of Nickel, although it is unstable in the cycle of charge-discharge, capable of storing more energy due to its higher valence charge. Modern Nickel electrodes are not ideal because of the low volumetric energy density of the active materials. Theoretical x-ray density of the Nickel hydroxide is 4.15 g/cm3but modern electrodes can reach a density of only 1.8 g/cm3. This is primarily due to the large microscale cavities, co-processed electrodes using conventional Nickel hydroxide.
The manganese dioxide (Mno2also currently available in nanostructured form. The size of the particles in natural and industrial synthesized manganese oxide lies in the range of microns or even millimeters. Natural manganese oxide is extremely polluted numerous oxide pollution, such as SiO2, Fe2ABOUT3A12ABOUT3and P2ABOUT5. These impurities complicate chemical and structural analysis of natural manganese dioxide and limit the possibility of its application.
Therefore, considerable interest in methods for the synthesis of the TLD is. himicheskie methods developed in the 1970s, give pure manganese dioxide micron size in many crystalline forms. Developed later, the synthesis reaction of salts of manganese (MnCl2or nSO4with a strong oxidant (KMPO4or a mixture of ozone and oxygen) gives a layered manganese dioxide. However, little or no was made attempts to obtain materials from the manganese dioxide nanostructure size or variable morphological form.
Crystallographic studies have shown that at the molecular level, the manganese dioxide is constructed of octahedra Mno6, each of which consists of six oxygen atoms surrounding the atom of manganese. The octahedra are connected by their vertices and edges, forming a single or double chains. These chains share corners with other circuits, resulting in structures with tunnels or channels formed by the atomic rows of cavities. The size of these channels is associated with a number of manganese-oxygen chains on each side. The presence of channels provides transport of mobile ionic substances, including Li+N+TO+BA+2, Na+or Pb+2. This feature is important, because such cationic exchange improves and kata.
The zirconium oxide (ZrO2) is another oxide, have attracted particular interest because of its stability, high hardness, fire resistance (ability to withstand high temperatures and ionic conductivity. Structurally stabilized Zirconia is widely used in thermal insulation coatings for modern engines that are exposed to extremely high temperatures. Other applications of zirconium oxide include ball mill, reflectors, oxygen sensors and fuel cells, and electronic ceramics.
Zirconia has a monoclinic structure at low temperatures, but exists in various forms at elevated temperatures. For example, unprotected Zirconia to monoclinic structure moves at approximately 1170oWith tetragonal structure and then at approximately 2370oWith a cubic structure. This transition is accompanied by a volume change, which can lead to mechanical damage to the parts. The presence of low-cations, such as MD+2, CA+2, Y+3and rare earth cations stabilizes the high-temperature phase at low temperatures, so that the metastable tetrago which has been created to obtain conventional micron-stabilized ZrO2include coprecipitation, microemulsion and Sol-gel synthesis. Modern methods for the synthesis of nanostructured zirconium oxide and yttrium-stabilized zirconium oxide (Y2ABOUT3/ZrO2) uneconomical as industrial processes. Methods of condensation in an inert gas (GCI) and chemical vapor condensation (HKP) is inherently very slow and therefore may not be effective, whereas the nanoparticles obtained by Sol-gel synthesis of highly agglomerated.
As you can see from the above discussion despite recent advances in the synthesis of nanostructured materials, there is still a need for materials and methods that would be inexpensive and gave the materials suitable for a wide range of industrial applications. There is a particular need for materials suitable for use as catalysts, i.e. materials with a high density of active sites and a good rate of percolation.
The disadvantages of the prior art, which are discussed above, are eliminated or alleviated materials and synthesis methods of the present invention, in which nanostructured oxide and hydroxide of metals is a and an aqueous solution of the reagent, at least one of which contains the previous Sol oxide or hydroxide; spraying an aqueous solution of reagent and water source solution in an aqueous source solution for obtaining nanostructured powder; heat treatment nanostructured powder to obtain the desired crystalline phase; selection crystalline phase; ultrasonic treatment of the crystalline phase to the disintegration of any of the components of the powder and for the introduction of lattice defects in nanocrystalline particles; spray drying the processed ultrasound powders for the preparation of nanostructured spherical agglomerates of powder. This method provides an extremely rapid nucleation of nanoparticles and inhibited the growth of nanoparticles, which leads to the formation of large volumes of nanostructured powders with a high density of active sites.
An important feature of the invention is that the method is simple, economic process, providing a General method of synthesis for a variety of nanostructured oxides and hydroxides of metals and other materials with improved properties and adjustable morphology and microstructure. Oxide and hydroxide have a particle size in the range of from about 1 cooperativ, where the agglomerates have a diameter in the range from about 0.1 up to 200.0 microns, preferably from about 1 to 100 microns and most preferably about 20 microns. The agglomerates are preferably porous, where the pores have a diameter in the range of from about 0.5 to 20 nm, preferably from about 1 to 10 nm, and most preferably about 5 nm, or are such that the nanostructured particles almost touch each other.
In another embodiment of the present invention provides a new class of nanostructured materials, characterized by the presence of fibers having diameters in the nanometer range. The presence of these nanostructured fibers results in materials with a high density of active centers and simultaneously improved the rate of percolation of the medium (gas or liquid). In one form these materials include a lot of nanostructured agglomerates with a high specific surface, where the agglomerates spatially separated from each other nanostructured fibers in the form of randomly interconnected loose tissue. In another form nanostructured materials include particles attached to nanostructured fibers in the form of randomly interconnected loose tissue. In the third form, materials uluchshit, nanostructured particles or fibers provide a high density of active centers to accelerate reactions solid/mobile medium (gas or liquid), while the nanostructured fibers provide a relatively easy way for the percolation of the reaction medium. High reaction rate, therefore, is the result of high density of active sites, as well as short distances inward diffusion and chemically active agglomerates of particles or fibers.
The new structure found in nanostructured Nickel hydroxide and manganese dioxide obtained by the method of the present invention. Nanostructured fibers have diameters less than about 100 nm, preferably less than about 50 nm, and most preferably in the range of from about 5 to 10 nm, and the ratio of the size (length/diameter) of more than about 10. Nanostructured fibers are separated from each other by a distance between about 0.5 and about 200 nm, and preferably in the range from about 5 to 50 nm, or fiber almost touching. Porosity loose tissue nanostructured fibers preferably greater than about 60 vol.% and more preferably more than about 80 vol.%, that provides high speed lane is approximately 0.1 to 200,0 μm, preferably from 1 to 100 μm, and most preferably about 20 microns. These composites of nanostructured agglomerates/fibers preferably contain more than about 60% of the volume of agglomerates of particles, and preferably more than about 90% by volume.
In another embodiment of the present invention offers nanostructured powders of particles of Nickel hydroxide. Such powders of Nickel hydroxide is used as the active materials for the positive Nickel electrode, the powder has a high specific surface area for optimum degree of contact between the electrode and electrolyte, and an adjustable degree of defects (both internal and external) that facilitates access of conductive substances or rapid movement of electrons and ions in the treated electrode.
In another embodiment of the present invention synthesized powders of alloy metal hydroxide Nickel nanostructured particles. These powders are suitable for use as active materials for electrodes in the latest high-energy batteries, where critical are large pulses of current when charging and during discharging.
In yet another embodiment of the present izopet is I. Nanostructured manganese dioxide is used as the active material for positive electrode, because it has high specific surface area for optimum degree of contact between the electrode and electrolyte, and an adjustable degree of defects (both internal and external) that facilitates access of conductive substances or rapid movement of electrons and ions in the treated electrode. Nanostructured alloy metal manganese dioxide is used for the electrodes in high-energy batteries. Nanostructured manganese dioxide is also synthesized with controlled structure defects, morphology and microstructure for many applications, including improved catalysts, fuel cells and devices for pollution control.
In yet another embodiment of the present invention proposed nanostructured particles of yttrium-stabilized zirconium oxide for use in the improved high-temperature ceramics and heat-shielding coatings.
The method according to the present invention can also be used for solid oxide and hydroxide of ceramic materials for wear-resistant, corrosio for curing in the volume of components and devices. The above and other features and advantages of the present invention will be perceived and understood by the specialists from the subsequent detailed description and drawings.
Fig.1 is a schematic representation of a known nanostructured material, showing the high proportion of atoms located at the edges or boundaries of the particles.
Fig. 2 is a diagram of the setup used in the method of aqueous solutions of the present invention.
Fig. 3A-3D are schematic representations of (A) agglomerates of nanostructured particles in accordance with the invention having a low degree of permeability; (C) bimodal (mixed) composites of nanostructured agglomerates of particles with nanostructured fibers of the present invention, having an average degree of permeability; (C) composites of nanostructured particles with nanostructured fibers of the present invention, with the degree of permeability is above average; and (D) chaotic loosely woven Assembly of nanostructured fibers of the present invention, having a high degree of permeability.
Fig.4 is a view of nanostructured Ni(OH)2according to the present invention under the filigree is t view of nanostructured Ni(OH)2according to the present invention under a microscope electron transfer (IPE), showing (A) equiaxial grain; and (C) a mixture of highly porous nanofibers and equiaxial particles.
Fig.6 is SAM-micrograms showing the structure of a bird's nest for nanostructured composite manganese dioxide of the present invention.
Fig. 7A-7D is SAM micrograms showing nanobiological the structure of the bird's nest of the present invention, occur (A) after deposition, (B) after heat treatment for 2 h, (C) after heat treatment for 8 h, and (D) after heat treatment for 24 hours
Fig.8 represents data roentgendifractometric (XRD), showing growth of nanostructured fibers manganese dioxide according to the invention with increasing duration of heat treatment.
Fig. 9A-9D are SEM-micrograms showing growth patterns of avian nest nanostructured fibers doped with cobalt (A) after deposition, (B) after heat treatment for 2 h, (C) after heat treatment for 12 h, and (D) after heat treatment within 48 hours
Fig. 10A and 10B are views lattice nanostructured fibers dioxide m the characteristic cross-section, normal to nanovolume where you see the tunnels and nanostructured lattice holes; and (C) shows an enlarged view of the tunnels lattice, where a schematic representation of a single cell (boundary shown on the right) superimposed on the image MPMR (both figures show the same type).
Fig.11A-11D are schematic diagrams of (a) the internal structure of the nanostructured fibers of the present invention, showing the edge dislocation dipoles, tunnels and nanostructured lattice of holes (In) internal active sites, (C) external active sites and (D) hybrid active nanostructured fibers, indicating internal and external active centers.
Fig.12A-12E schematically show the transformation of the structure of birds 'nests manganese dioxide of the present invention: (A) agglomerates of nanoparticles (In) introduced the germ of nanofibers, (C) converted long fibers, (D) interpenetrating beams of fibers and (E) fully developed structure of birds' nests.
Fig. 13A and 13B represent (A) NEVR image nanostructured fiber Mno2according to the invention, seen perpendicular to the cross section are fulfilled, and (B) schematic representation of dislo is B>2according to the invention, seen parallel to the axis of the fiber, showing (A) the end-point of a line dislocation with four dislocations faces, where the axis of the dislocation of the arrows; and (C) various forms of the fiber surface.
Fig. 15A and 15C represent the size distribution of the pores of nanostructured fibrous material of manganese dioxide with (A) copper concentrations of 0.1 M and (B) the copper concentration of 0.4 M
Fig. 16A and 16B represent the curves of the hysteresis of adsorption/desorption for (A) 0.1 M copper, added as additive in the manganese dioxide, and (C) 0.4 M copper, added as additive in the manganese dioxide.
Fig.17A and 17B are: (A) the IPE-micrograms showing the morphology of the particles of nanostructured yttrium-stabilized zirconium oxide, synthesized according to the present invention, and (B) MPMR-micrograms showing the type of lattice particles in (A).
In accordance with the method of the present invention nanostructured oxides and hydroxides of the metals are produced using aqueous chemical solution, including the receipt of the initial aqueous solution and an aqueous solution of the reagent, at least one of which contains at least one preceding salt of the metal; spraying water RA is ructures powder to obtain the desired crystalline phase; the selection of the crystalline phase; ultrasonic treatment of the crystalline phase to the disintegration of any of the components of the powder and for the introduction of lattice defects in nanocrystalline particles; spray drying the processed ultrasound powders for the preparation of nanostructured spherical agglomerates of powder. This method provides an extremely rapid nucleation of nanoparticles and inhibited the growth of nanoparticles, which leads to the formation of large volumes of nanostructured powders with a high density of active sites. These nanostructured oxide and gidrookisyei materials are suitable for a wide variety of applications, including highly active catalysts, rechargeable battery, fuel cell and molecular sieves; a highly porous structure that provides the percolation of the reaction gas and liquid phases, with the simultaneous contact of the reaction gas or liquid phase with a high density of active sites within units of the nanostructure material; a porous ceramic materials for thermal insulation coatings; thick ceramic coating; and powders for bulk curing to obtain nanostructured ceramic components. The method is also suitable for other nanostruc the si and hydroxide, according to the method of the present invention shown in Fig.2. The installation 10 includes a reaction vessel 12 containing the original solution 14, equipped with a stirrer 16, pH-electrode 18, the source base or oxidizing agent 20 and the spray system 22. The spray system includes a nozzle 24 for supplying the reagent solution 26. As shown in Fig.2, the sputtering may be carried out by the gas 28, for example, N2or sound (not shown). The system further includes a pipe 30, is equipped with high-performance pump 32 for recirculation of the initial solution 14. Recycled original solution 14 sprayed into the reaction vessel 12 through the nozzle 34. Simultaneous spraying and initial solution 14 and the reagent solution 26 into the reaction vessel 12 provides a mixture of the reactants at the molecular level.
Procedure for the synthesis of nanostructured oxides and hydroxides in large quantities in General includes, first of all, the synthesis of nanostructured oxide or hydroxide by precipitation from a mixture of aqueous starting solution and an aqueous solution of the reagent. Aqueous solutions are prepared from water-soluble chemicals and contain at least one preceding salt of the metal or rare earth element and oxidizing agents and/or bases, depending on dopolnitelnuyu salt of the metal or rare earth element, to enter doped nanostructured metal powders with predetermined chemical, structural and performance.
The deposition is initiated by the spraying of the reagent solution and the aqueous starting solution in the reaction vessel containing the aqueous source solution. Used herein, the term "reagent solution" means a solution which is sprayed, and the "original solution" means a solution in the vessel 12, which is pumped through the pipe 30 and is sprayed in aerosol contact sprayed with the reagent solution. These terms are introduced only for convenience, since the following description and examples clearly show that the earlier salt (or salt) metal can be dissolved or in the reagent solution or the initial solution depending on the specific composition of the synthesized oxide or hydroxide. Spraying can be carried out by pressure or ultrasound. Using co-sputtering for dilution of the original solution and the reagent solution means that the formation of nuclei and growth of precipitate nanostructured powder can be accurately and reproducibly adjusted. The precipitate may be in the form of amorphous powder, partially crystalline powder or cristalli the IRS or hydroxide, include pH, concentration of the preceding salts and other reagents and the feed rate of solution.
After deposition of nanostructured powder is subjected to aging or heat treatment for a time sufficient to convert fully or partially crystalline nanostructured powder into the desired crystalline state. This procedure is crucial, as it is intended for stabilization of nanocrystalline structure. The process parameters that determine the morphology and yield of nanocrystalline powder product, include the heating temperature, heating time and the pH of the solution.
After aging or heat treatment of nanocrystalline powders are usually isolated by filtration and washed to remove by-products, preferably using deionized distilled water or other suitable solvent.
The next stage is the ultrasonic treatment of a suspension of nanocrystalline particles using ultrasonic probe. Ultrasonic treatment disintegrates any aggregates of powder and introduces lattice defects in nanocrystalline particles. These defects can have Valevich electrodes. The parameters that affect the final product, include power ultrasound and processing time.
The final stage is spray drying the processed ultrasound suspension of nanoparticles to obtain nanoporous spherical agglomerates of powder. This procedure gives the agglomerates of nanostructured particles, where the agglomerates have a diameter in the range of from about 0.1 to 200 μm, preferably from 1 to 100 μm, and most preferably about 20 microns. During spray drying is rapid evaporation when sprayed droplets come into contact with a stream of hot air to form a film of saturated steam. The duration of evaporation depends on the rate of diffusion of moisture through the surface membrane. As the shell thickness increases over time, there has been a corresponding decrease in the evaporation rate. Because evaporation is an endothermic process, the surface of the droplets remains cold up until evaporation is complete, despite the fact that the air flow can be quite hot. The use of aerosol spray drying ensures that the final powder (i.e., Ni(OH)2does not contain unwanted phase, kotoraja raw materials, the gas temperature at the inlet and outlet and Concentratio suspension.
Options above five successive stages were used in the synthesis of nanostructured materials of different composition. For example, in the synthesis of yttrium-stabilized zirconium oxide, precipitated powders were first identified and then treated with ultrasound with subsequent heat treatment. Powders after heat treatment was dispersible in aqueous binders, for example polyvinyl alcohol (PVA) before spray drying.
The techniques used to control the kinetics of chemical reactions and the formation and growth of nuclei precipitated phases are crucial for the implementation of the present invention. These driving techniques include: (I) the use of sputtering to connect the source reagents; (II) thermal treatment of a reagent solution at a given pH and reaction time; (III) ultrasonic processing of nanostructured powders, suspensions; (IV) the use of surface-active substances, and (V) spray drying the nanoparticles to produce the desired agglomerates with adjustable porosity.
The materials synthesized according to the present invention, include nanostructure what tallamy, including, but not limited to these. Co, Al, Cd, Mn, Zn and other transition metals. Can be also obtained particulate and fibrous nanostructured manganese dioxide and particulate and fibrous nanostructured manganese dioxide, alloy of Co, Fe, Pt and other additives, as well as dispersed nanostructured zirconium oxide stabilized with yttrium. Other pure, mixed or complex oxide and hydroxide, suitable for the synthesis of the above method include aluminum, silicon, magnesium, zinc, molybdenum, yttrium, zirconium, copper, cobalt, vanadium, silver, titanium, iron, Nickel and tungsten, and rare earth metals. These and other elements known in practice, such as alkali metals, precious metals and semi-metals can be used as an alloying agent.
In particular, the implementation of the method according to the invention led to the synthesis of a new class of nanostructured materials, including fibers having diameters in the nanometer range. The presence of such nanostructured fibers gives materials with a high density of active sites at superior speeds percolation medium (gas or liquid). Fig.3 shows the new structure according to the invention in sravneniyu particles 52 is limited by the surface 54 of the agglomerate 50.
The first form of the new morphology of the present invention shown in Fig. 3B, where the composites 60 according to the invention include agglomerates 62 nanostructured particles with a high density of active sites for the acceleration of the reaction environment/solid and fibrous loosely woven units 66, which provide a relatively easy way for the percolation of the reaction liquid or gas through the composite 60. Reagents passing through the nanostructured fibers 68 forming Assembly 66, thereby continuously in contact with the agglomerates of the nanoparticles. A short distance diffusion into and out chemically or catalytically active agglomerates provide a high reaction rate.
The second form of the new morphology of the present invention (Fig.3C) composite 70 is comprised of nanostructured particles 72 attached to nanostructured fibers 74 in the form of randomly interconnected loosely woven Assembly 76. Again loose fibrous Assembly 76 provides a relatively easy way percolation of the reaction liquid or gas through the composite 70, and reagents passing through the nanostructured fibers 74, thus, continuously in contact with the nanostructured particles 72. A short distance on the third form contains 80 nanostructured fibers 82 in the form of randomly interconnected loosely woven Assembly 84. Here themselves fibers provide a high density of active sites for the acceleration of the reactions of solid fluid medium (gas or liquid).
These new structures are easily formed during the synthesis process of the present invention under the conditions described in detail below. Under these conditions, the agglomerates of nanostructured particles gradually transformed into fibrous objects, each of which contains a three-dimensional chaotic loose fabric of nanostructured fibers. The transformation occurs from the outer surface to the core of the original agglomerates of nanostructured particles. Complete transformation gives loosely woven structure with a typical bulk density not less than about 20%. Nanostructured fibers have a diameter of less than about 100 nm, preferably less than about 50 nm, and most preferably in the range of from about 5 to 10 nm, and aspect ratio (length/diameter) of more than about 10.
Relatively small variations in the synthesis conditions lead to large variations in the size, shape and distribution and the initial agglomerates of the nanoparticles and the resulting nanostructured fibers and assemblies. For use as a catalyst and in other areas it is preferable that PR is nocturnia particles separated by a thin layer of interconnected nanostructured fibers. Such morphology of the composite network structure with a high density of active sites and high specific surface area, and increased the speed of percolation in the space between the agglomerates. Variations of the relative volume fraction of agglomerates of nanostructured particles and nanostructured fibers or nanostructured particles and nanostructured fibers lead to variations in the level of chemical reactivity and rate of percolation environment and allow thus to optimize the material for a particular application. For some applications the preferred nanostructured fibers with distance between them of from about 0.5 to about 200 nm, preferably from about 5 to about 50 nm, or almost in contact with each other. The porosity of this nanofiber loosely woven fabric preferably more than about 60% of the volume, and more preferably more than 80% of the volume, which provides a high rate of percolation substances. The composites preferably comprise greater than about 60 vol.% agglomerates of nanostructured particles and preferably more than about 90 vol.%.
The observed transformation of nanoparticles/nanofibers associated with a significant decrease in deutronomy, the current in the solution phase, with the reaction going mainly by reducing the surface energy. This mechanism represents an increase of fiber through the gradual dissolution of the nanopowder in the liquid phase, followed by transport of the liquid phase from the dissolved particles to the growing ends of the nanofibers. This simple mechanism escalation should be common to many other systems, so the present invention should be applicable to a wide range of compositions.
The new material described here is suitable for a wide range of use of the catalyst comprising devices for pollution control, fuel cells, rechargeable batteries, molecular sieves and synthetic catalysts. Device for pollution control include those that have the air filters or fluids for automobiles or other vehicles, or for houses, offices and buildings.
Another application in this area is the application of catalytic coatings on large areas, such as electrophoretic deposition, where the imposition of an electric field across electrostatically stabilized colloidal suspension provides the driving force for% trafarettidega mobility (speed shift divided by the electric field) does not depend on the particle size. Another advantage is the ability to quickly homogeneous deposition of sediment on the complex geometric shapes, such as various filters used in automobiles, aircraft and other vehicles.
There is also an urgent need for devices for pollution control, which can reduce the content of particles with sizes of the order of several microns, and devices that can reduce the CO content, SOxand NOx. Nanostructured materials having a high rate of percolation, are well suited for these purposes. Other applications include water purification, air filtration, purification from heavy metals such as mercury, and cleanup of nuclear emissions.
With regard to the application for fuel cells, the modern fuel cells use expensive alloys of noble metals such as platinum in phosphoroclastic elements, and platinum-ruthenium in direct methanol elements. In performability elements of the platinum particles are mixed with the substrate of graphitized carbon in order to maximize the usefulness of the material of the active centers. Istri tunneling centers, (II) predominantly on the manganese centers of the lattice, and (III) on the surface centers. A new approach increases the power density of fuel cells, and also increases the time of their life. In solid fuel cells nanostructured materials with a high density of active sites of the present invention is used in the form of fuel elements with subtle energetic film of zirconium. This type of fuel cell is preferred compared to modern high-temperature solid fuel elements.
Another important area of application of nanostructured fibers of the present invention, in particular fibres of manganese dioxide, is their application in rechargeable batteries. Nanostructured fibrous alloy lithium manganese dioxide is ideal for use in rechargeable batteries due to the ease with which the lithium cations can diffuse inward and outward molecular cell structure of defects manganese dioxide. In General, such this nanofiber structures can also serve as excellent cation exchange materials. In addition, when the specific surface area of more than about 250 m2/g they are outstanding Catalytica the x rechargeable battery packs. This type of material is also used in Zinkovsky systems batteries.
Nanostructured fiber dioxide of manganese have a molecular tunnel 4.6 Angstrom x 4.6 angstroms. As the analysis shows specific surface, synthetic materials there are two types of porosity: (I) the porosity of the nanometer scale with a pore size from about 2 to 20 nm; and (II) the porosity of the scale of angstroms with a pore size of from about 5.6 to 9.2 angstroms. It makes you think about the use of the material as molecular sieves, for example, to remove unwanted organic compounds from petroleum products.
Due to the special characteristics of manganese dioxide, its acidity can be modified by alloying various metals. Alloy metal manganese dioxide can be used as acid-base or redox catalyst. Previous work on pellets manganese oxide showed that the manganese dioxide is particularly effective in the decomposition of alcohols, oxidation of carbon monoxide, the restoration of NOx, hydrogenation, demetallization of petroleum residues, decomposition of organic sulfur compounds, decomposition of organic nitrogen from the ranks of the invention are illustrated below by examples, not restrictive.
EXAMPLE 1. Nanostructured Nickel hydroxide
A. dispersed Nanostructured Ni(OH)2< / BR>
The raw materials used to produce nanostructured powders of Nickel hydroxide, included the uranyl of Nickel nitrate Ni(NO3)26N2Oh, the uranyl of Nickel chloride NiCl26H2O or Nickel sulfate with NISO46H2O, sodium hydroxide, NaOH, and sodium carbonate PA2CO3. Synthesis of nanostructured Ni(OH)2in the interaction of Nickel halide with sodium hydroxide can be described by the following reaction:
Ni(NO3)2(aq)+2NaOH(aq)-->Ni(OH)2(S)+2NaNO3(aq). (1)
The formation of nanostructured Ni(OH)2high surface area depends on the pH of the reagent solution, the regulation of the education centres of nucleation spray reagents, time of annealing and temperature during irrigation flow with controlled pH and ultrasonic excitation of rainfall. Synthesis of about 0.45 kg of nanostructured Ni(OH)2described below.
First prepare a water previous solution of 1700 grams Ni(NO3)26N2Oh dissolved in 15 liters of distilled deionized water. The deposition is conducted first of Nickel salt solution through the pressure nozzle with a speed of 2.5 l/h, in order to maintain the desired pH value in the range of from about 7 to 12. Higher pH values lead to strongly agglomerated particles, whereas lower pH does not allow the reaction completely. During co-sputtering source solution and reagent solution formed suspension is green, which contains turbostrategy the form Ni(OH)2(turbostrategy form is intermediate between the amorphous and crystalline). In another embodiment, NiCl2can also be sprayed in the original solution through the second nozzle.
After precipitation, the suspension is subjected to heat treatment at about 65oC for 2-12 h, while maintaining a pH in the range of from about 7 to 12, which translates turbostrategy crystalline structure to a more stable form. This procedure is crucial, as it is designed to stabilize the nanocrystalline structure of the Ni(OH)2and its electronic properties. The slurry is then separated by filtration and washed with distilled deionized water to remove sodium nitrate and other undesirable by-products.
Nanocrystalline Ni(OH)2then resuspended in the distilled snasti output of 500 W, length 15 cm, diameter 2.5 cm) with a flow-through cell for continuous operation. Ultrasonic treatment breaks all aggregates of the powder and enters the surface defects and lattice defects in nanostructured particles. These effects can have an important impact on the behavior of the active material in the Nickel electrode.
Finally, the nanoparticles preferably subjected to spray drying for the formation of nanoporous spherical powder agglomerates having diameters in the preferred range of about 1-20 microns. Spray drying provides further processing of the powder. Spray drying is preferably carried out so as to provide fast and efficient drying of the aerosol, in order to obtain a homogeneous fully dried powder product, but at the same time to retain the structural water and to avoid overheating of the powder. Preservation of structural water in the powder of Nickel hydroxide is identifying important because it will very strongly influence the properties of the active nickelhydrogen material in the treated electrode, for example, the percentage of use of the material, but also on the characteristics of charging and discharging. Important is the regulation of temperatureoC.
Judging by roentgendifractometric (XRD), synthetic nanostructured powder has-Ni(OH)2-structure. SAM micrograms (Fig.4) powder after spray drying show that they represent a spherical solid particles with a diameter in the range of from about 1 to 20 microns, although detailed information was not obtained. Studies of IPE, however, showed that the particles of Nickel hydroxide after spray drying are agglomerates of many small
nanostructured particles having diameters in the range from 2 nm to several tens of nanometers, and most of the particles less than 10 nm (Fig.5A). The average particle size calculated by the extension of the peak x-ray radiation is about 5 nm.
-Ni(OH)2consists of structures type of sandwich with the plane of the Ni atoms inside the lattice of oxygen atoms (HE). Theoretical x-ray density of the active material-Ni(OH)2approximately 4.15 g/cm3. Real density normal nickelhydrogen material is about 1.6 - 1.8 g/cm3. Existing spherical powders Japanese Tanaka, the reference of which is given above, can have a bulk density of up to 2.1 g/cm3. Nanoscientific conditions. It is clear that when compared with currently available materials nanostructured Nickel hydroxide has a much better performance bulk density and intensity.
C. dispersed Nanostructured Ni(OB)2alloyed with cobalt and other transition metals
Experimental procedure for the synthesis of cobalt alloy Ni(OH)2basically the same as described above. With(NO3)2in a given atomic ratio (1-20% nuclear) is added to aqueous solution of Ni(NO3)2before spraying. X-ray analysis of the powders after heat treatment and after spray drying shows that the doped cobalt material has a-Ni(OH)2crystal structure, which were not found in other phases. The morphology and microstructure similar to those for non-alloyed Ni(OH)2.
Doping in place of nanostructured Nickel hydroxide according to the invention metal elements such as cobalt and other transition metals, such as zinc and manganese, and heavy metals, including cadmium, further enhances the characterization of nanostructured Nickel electrodes. The main problems associated with poor behavior of modern Nickel is ity between the active material and a porous Nickel substrate. To address these problems at the present time to the active electrode paste add the cobalt oxide so that the cobalt oxide was slowly dissolved in the lattice of Nickel on the surface of the powder of Nickel hydroxide. However, cobalt is usually still present only on the surface of particles of micron size. The present invention has the advantage that it allows you to add the cobalt or other alloying ion at the molecular level.
C. Nanostructured particulate and fibrous Ni(OH)2alloyed aluminum
When alloying the Nickel hydroxide aluminum using aluminum nitrate (A1(NO3)3N20) in accordance with the above procedure, the lattice-Ni(OH)2transforms into the stable-Ni(OH)2. Transformation occurs gradually as a function of the amount of the alloying additives. For example, at low concentrations of aluminum, up to 5% atomic, crystal structure of a Ni(OH)2; at higher concentrations of aluminum crystals gradually transformed-Ni(OH)2;- Ni(OH)2found at 20% atomic aluminum. Initial tests of the characteristics of the electrode show that the La of the next generation of electric vehicles more than 200 mAh/g).
Nanostructured Ni(OH)2synthesized in accordance with the present method, may also have a fibrous structure. Powders of Nickel hydroxide after spray drying detect a spherical morphology in the analysis of SAM, which is described above as an agglomeration of many nanostructured particles of Nickel hydroxide. Micrograms of material at higher magnification using the IPE show that depending on the parameters of the synthesis of the individual components can be or simply nanostructured particles, as shown in Fig. 5A, or a mixture of nanostructured fibers with equiaxial particles, as shown in Fig.5V.
Particles of the composite shown in Fig.5B, obtained by synthesis in the presence of from 5 to 10 and up to 20% atomic aluminum.
EXAMPLE 2. Nanostructured manganese dioxide
A. Nanostructured particulate and fibrous Mno2< / BR>
Nanostructured particles and highly porous nanostructured fiber manganese dioxide synthesized by the reaction of an aqueous solution of salts of alkaline metal permanganate, for example, potassium permanganate (CMP4) sulfate, manganese (MnS04in the presence of nitric acid in accordance with the following reaction:
2MnO4< synthesize, dissolving 55 g nS04in 188 ml of deionized distilled water, and bringing the pH of the solution to a value not less than 1 by adding NGO3. The reagent solution containing 36,8 g CMP4in 625 ml of deionized distilled water, is injected in the form of a spray or aerosol into the reaction vessel containing the circulating mixture nS04/NGO3with vigorous stirring the solution in the reaction vessel. As mentioned above in the description of Fig.2, the recirculating mother liquor is sprayed together with the reagent solution. Molecular mixing of the reagent solution and the original solution leads to the formation of colored coffee color colloidal suspension of nanostructured manganese dioxide. Analysis of a sample of dried powder of this suspension shows amorphous particles having a diameter less than 10 microns.
The colloidal suspension is then subjected to heat treatment in the reaction vessel at a temperature effective to remove water, preferably in the range from 100 to 120oC for 2-24 hours Heat treatment is gradually transforming the amorphous particles in the chaotic fabric of nanostructured fibers. For complete transformation requires a heat treatment for about 24 hours Pic the second dial tone, in order to minimize the possible agglomeration of the products of the synthesis of manganese dioxide. The resulting nanostructured fibrous products is filtered and washed with distilled deionized water to remove undesirable side reaction products. Finally the washed fibrous powders of manganese dioxide is dispersed in a surface-active substance, such as ethanol by ultrasonic treatment, isolated by filtration and dried in an oven at 100oC for 4-12 hours.
Consideration of these fiber powders of manganese dioxide under the scanning electron microscope (SEM) shows wave-like fibrous mesh (Fig. 6). Although higher resolution available for SAM, micrograms show the characteristic morphology of the "bird's nest", which appears in the weave of fibers, where each "bird's nest" has a diameter of about 10 microns and is an Assembly of many individual nanostructured fibers.
Century Influence of process parameters on the crystal structure of Mno2< / BR>
The formation of nanostructured manganese dioxide having a fibrous structure, depends on the proper choice of the concentration of nitric acid, the temperature of the heat abrevadero flow during heat treatment of from about 60 to 100oWith the passage of time from a few hours up to 48 hours result in the morphology of bird nests, consisting of fibers with a diameter in the range of 5 to 25 nm, where each bird's nest has a diameter of about 10 μm. Systematic studies have been conducted in order to determine the conditions for optimization of hollandite crystal structure of manganese dioxide in the process of chemical synthesis. Studies have shown that manganese dioxide synthesized without adding nitric acid to the solution of sulphate of manganese shows negligible crystallinity and can be considered as essentially amorphous. In contrast, the manganese dioxide synthesized with the addition of nitric acid has a pronounced crystalline structure. As a consequence of this discovery, synthesis used standard pH is less than 1.
The duration of heat treatment is crucial for obtaining nanostructured manganese dioxide. When combined spraying of the reagent solution KMPO4solution MnSO4in the presence of an oxidant formed amorphous powder. Typical SAM-micrograms per Fig.7A shows that this amorphous powder consists of spherical agglomerates with a diameter of prolecia at 60oC for 2 h increases the size of the initial agglomerates of 0.5-3 μm. The surface of some agglomerated mass begins to show the development of the fibrous structure surface with numerous fibers protruding from the surface of the agglomerated mass, as shown in Fig.7V. There are also free from fiber agglomerates.
After 4 h of heat treatment at the same temperature the size of the agglomerated mass grows to 1-5 μm, and the fibrous surface structure appears much stronger. Not observed changes in the inner part of the mass of agglomerated particles. While the structure still to be formed very small fibers, apparently, the largest fiber reaches a maximum size of about 25 nm in cross section and of approximately 0.5 microns in length.
After 6-8 h of heat treatment of many of the larger agglomerates show a well-developed fibrous structure or morphology of the "bird's nest", which consists of three-dimensional chaotic loose fabric of fibers (Fig.7C).
After 24 h heat treatment of the fibrous structure of the bird's nest was fully developed, with no visible remnants of the original nanotm, including many woven into the fibres passing through the entire structure (Fig.7D).
Fig. 8 shows the data RD (x-ray diffraction analysis of samples taken after the aforementioned periods of irrigation. Svezheosazhdennoi powders had a very broad peak at 35o2. After 2 h of irrigation start to develop the peak of (020) with approximately 66o2 and the reflection type (211) with approximately 37,5o2. These two peaks are associated with the early growth of fibers. After heating this solution with irrigation within 4 hours start to develop all other major RDA-peaks, including the characteristic peak (200) to about 17.5o2. The width of the peak (200) is related to the diameter of the nanofibers. All these peaks are broad, indicating that the fibers have small dimensions. After 8 h of heating with irrigation, RDA-peaks continue to evolve, but still remain relatively wide, showing, at this stage, some amphora substrate in the diffraction grating. After 16 h of heating solution with irrigation, were obtained by a well-developed RDA-peaks for phase hollandite cryptomelane type, and were not found any significant amphora substrate. Judging by the SEM-analyses after 24 h under irrigation fully develops fibrous structure with fiber is th Mno2alloyed With Her and Pt
General procedure for the synthesis of nanostructured manganese dioxide containing the selected alloying elements, such as that used in the synthesis of undoped materials, but additionally includes the addition of an aqueous solution of the corresponding metal halide to a solution of MnS04. For example, upon receipt of 50 g of powder doped with 0.4 M cobalt 123 ml of 7M(NO3)6N2About add to the solution MnS4prior to its reaction with the oxidant KMPO4. Alloyed with cobalt manganese dioxide gives fibrous superstructure of bird's nest that is affected by the conditions of synthesis of manganese dioxide, in particular, the time of heat treatment and concentration of cobalt, as will be described below.
After the deposition of the alloy of cobalt, manganese dioxide outwardly similar to the unalloyed powder of manganese dioxide. Nanostructured particles have a diameter of from about 0.1 to 0.5 μm and are in the form of spherical agglomerates (Fig.9A). Even at this stage, small bolognapadova patterns begin to appear on the surface of the agglomerated nanostructured particles. When heated at 60oC for 2 h develop corruptable patterns (Fig.9B), Hara is e 12 h of heating the initial corruptable patterns change in a more agglomerated mass from the initial appearance of the morphology of bird nests (Fig.9C). Agglomerated mass has a size from about 0.5 microns to about 3 microns. On the surface begin to grow a mustache, while the inside of the agglomerates is still like. The size of these whiskers ranges from a few nanometers to about 20 nm in diameter and from a few tens of nanometers up to about 0.5 microns in length. After 24 h of heating, the sizes of the agglomerated mass increase to approximately 3-10 microns and now they are mostly composed of twisted fibers that form the morphology of bird nests. The maximum fiber diameter of approximately 25 nm at length in the range from several tens of nanometers to micron range. At this stage, however, still remains a small proportion neprivrednih corruptable particles smaller size. After heating for 48 h at the same temperature obtained a fully developed structure of bird's nest of twisted fibers (Fig.90).
The duration of the heat treatment of the deposited powder dioxide cobalt-manganese has had a tangible effect on the specific surface of the powder. Svezheosazhdennoi material has a specific surface area of about 150 m2/, After 0.5 h of heating, however, the specific surface increases docent small fibers on the surface of the agglomerates create a lot of centers of crystallization. The specific surface of powders starts to decrease after 2 h of heating to 170 m2/, This reduction continues until the full development of the fibers. Fully developed nanostructured fibrous Co-Mno2with 4,819 wt.% cobalt has a specific surface area of 120 m2/g, whereas alloy and iron-manganese dioxide can have a specific surface of up to 280 m2/,
D. Morphological characteristics of nanostructured Mno2< / BR>
(a) Direct studies of atomic lattices
Scanning electron microscopy of manganese dioxide after heat treatment shows the existence of organizations such as bird nests, United nanostructured fibers manganese dioxide, as shown in Fig.6. The IPE indicates that the individual fibers are cylindrical single crystals having a fiber diameter in the range of from about 5 to 50 nanometers and a length in the range from several tens of nanometers to about 1-3 μm. Structural analysis additionally confirmed that nanofibers are composed of oriented along the axis b of single crystals, which have hollandicum the structure and composition of the corresponding KMn8O16. In this structure, about half is available To the, what makes it particularly attractive for catalysis and ion exchange. Typically materials having pores of such nanoscale are excellent cation exchange materials. In addition, when the specific surface area of more than 2002/g they are good catalytic materials for oxidative reactions and ionic-electronic conductors for high-capacity rechargeable and rechargeable batteries.
For analysis of individual nanofibers were also used NEVR in two directions. Fig.10 is a picture NEVR fiber cross-section parallel to the b-axis of the nanofibers. Fig.10B shows an enlarged view of the tunnels of the lattice in the same the micrograms. Schematic illustration of the atomic orientation imposed on the micrograms with boundaries that are defined by the insert on the right. Tunnels grilles are visible on the projection computer models and MPMR-micrograms. All tunnels are double chains of octahedra MP, and each pair of chains connected under approximately a right angle, forming a square structure (22). These molecular tunnels are sized In contrast, there are often also much large nano-holes or pores of a diameter of 1-2 nm. A hole with a diameter of approximately 1 n is cteristic growth structures, bird's nest
Fig. 12 shows the growth of fibers at different stages, namely: smooth surface svezheosazhdennoi dioxide manganese (Fig.12A), the formation of the embryonic fibers that begin on the surface of the agglomerated masses after a few hours of heat treatment (Fig.12V); their growth to long bundles of fibers (Fig. 12C); the subsequent penetration of the fibers (Fig.12D); and, finally, three-dimensional chaotic loosely woven structure (Fig.12E). An important factor in this growth is the downward growth of nanostructured fibers in an amorphous substrate. Not connecting it with theory, it may simply be the result of short-range diffusion in the solid state through the substrate to the growing root nanofibres, as the crystalline structure is more stable than the amorphous state.
In the chemical potentials of the ions of manganese and oxygen will be facing a declining gradient to any crystalline region in contact with an amorphous agglomerate. From this we can conclude that the downward growth is an example of the mechanism of consolidation, the current in the solution phase, where the reaction occurs primarily by reducing energy surface. Such a mechanism is the increase in the fiber during gradual the Itza to the growing tips of the nanofibers. This simple mechanism of consolidation may be common to many other systems materials, so that the present invention can be widely applied to many songs.
That is, the Defect structures
(a) Structural defects
In nanostructured fibers were also observed imperfections in crystals or defects. As shown in Fig.13A and 13B, the edge dislocation dipoles (line defects) of opposite sign are visible, if we consider the fiber perpendicular to its cylindrical surface (or in the direction of the tunnel). These edge dislocation dipoles will result in the formation of rows of vacancies, which provides a path for rapid diffusion of atomic and/or electronic particle diameter across the nanofibers. These dislocations end along a straight line which is normal to the growth axis or b-axis. More precisely, these dipoles create a series of vacancies (void), normal to the axis of the nanofibers, as shown in Fig.11A. Similarly the end of the dislocation lines are parallel to the growth axis, seen in the direction parallel to the direction of the tunnel (cross-section of the fiber), as shown in Fig.14A. This line of dislocation emerges from the intersection of the four above-mentioned dislocation lines, novolokina has consequences associated with this nanocolonies material. In ionic crystals dislocations, ending inside of fibers will create effective charges associated with merging centers dislocation. The sign of these charges depends on the atomic environment of the void. The substitution element of opposite sign can change the effective charge of the cavities on the opposite simple side substitution to maintain charge balance. Found that the effective charge created by the end of dislocations within the crystal will have a triangular shape.
Because you are dealing with an ionic crystals, the existence of dislocations, ending inside the fiber, is mainly to create effective charges associated with fused center dislocations, located in this case diametrically opposed across the grain. We should expect that the square tunnels lattice 0,46 x 0,46 nm will be ideal for replacement of lithium ions. In addition, the high density of atomic steps (Fig.14C) are easily identified at the sight, parallel to the growth axis of the fiber, and it can function as active centers from the energy point of view.
Another feature of the new structures is Aristote can be modified by doping with different concentrations of transition metals. Material with internal defects are shown schematically in Fig. 11B, and alloyed materials with defects and materials with hybrid characteristics of the defects are shown schematically in Fig.11C and 11D.
(b) Porosity and specific surface
Nanostructured fibrous manganese dioxide has a high specific surface area and relatively small pore size. Another important feature of the synthetic material is that its properties can be significantly modified by changing the type and concentration of the alloying additives. For example, with the introduction of iron as alloying additives as measured by the BET method specific surface area can be increased to 280 m2/g with pore volume 0,323 cm3/g pore Volume was measured by introducing a sample of liquid nitrogen, where the pore volume (Vp) was calculated as Vp=(weight of N2)/(density N2). The volumes are then listed in the following table, which shows measured by the BET method specific surface area nanostructured fibrous dioxide manganese, alloy different concentrations of cobalt, copper and iron, showing voids caused by mikroporistogo and metophorically.
Microporosity is defined as the porosity with a pore diameter IU is Wookie manganese 0.1 M and 0.4 M copper shown in Fig.15A and 15C. For example, when the doping of 0.1 M copper detected pore diameters in two sizes and 85% then refer to the size . However, when the copper concentration is increased to 0.4 M 70% of the pores have a size which may be due to the fact that by increasing the concentration of alloying a large part of the pore is blocked by the copper. Microporosity associated with lattice defects, including large holes that exist in the fibers.
Misoprostol is defined as porosity with pores of diameter greater than the Data misoprostole receive adsorption-desorption method. Misoprostol found in synthetic manganese dioxide, depends on how laid and connected to its fiber. Fig.16A and 16B show the isotherms of adsorption/desorption of samples of manganese dioxide, doped, 0.1 M and 0.4 M copper. Both isotherms are of type II (i.e. cylindrical, slotted or square) on the classification of Brunauer et al. for materials with microporosity and metophorically described in Journal of American Chemical Society, Vol.62, 1723 (1940).
The pore volume of micropores close to 25 cm3/g for both samples. The value of the adsorption of R/Raboutit was estimated in the range of 0.1 to 0.95, which is associated with metophorically, increasing p is but due to the adherence of the fibers to the domains of copper. Similarly, the hysteresis observed for samples of 0.4 M copper in the range of R/Rabout0,8-0,9, associated with the presence of then type "ink" may be clogged by the deposition of particles of copper.
EXAMPLE 3. Nanostructured zirconium oxide stabilized with yttrium
Factors determining the quality of the final product powder Y2O3/ZrO2include pH, the concentration of the solution, the formation and growth of nuclei and the concentration of the additive surfactant. The source materials are zirconium chloride (ZrOCl28H2O), yttrium chloride (OS36N2O) and ammonium hydroxide (NH4OH). Synthesis of yttrium-stabilized zirconium oxide is conducted according to the following reaction:
[Zr(OH)24H2O]+8-->[Zr(OH)2+x(4-x)H2O]4(8-4x)+4xH+. (3)
General synthesis procedure similar to that described above. Aqueous solutions of the chemicals ZrOCl28H2O US36N2About spray together, as shown in Fig.2, the reaction vessel containing the recycled mother liquor NH4OH in distilled deionized water under vigorous stirring the resulting aqueous mixture. To maintain the pH NH4HE continuously add in reaction and then dried, getting hydroxide powder yttrium/zirconium, which is then subjected to heat treatment at elevated temperatures, to obtain the finished powder nanostructured Y2O3/ZrO2.
Receive from 0.5 to 1 kg nanostructured powder Y2ABOUT3/Zr2containing 7% nuclear Y2ABOUT3begin with the preparation of aqueous solutions of 1120 g ZrOCl28H2O and 250 g US36N2ABOUT US36N2About 22.4 l of deionized distilled water. (The composition having a different content of yttrium, prepare, changing the number US36N2On the solutions of the reagent). Deposition occurs when the joint application of this aqueous solution of salts in aqueous solution of NH4OH in the reaction vessel through a nozzle under pressure of NH4HE also added as needed to maintain the pH of the water solution in the interval between 8 and 11. After adding an aqueous solution of salts completed, the solution was additionally stirred for 2-4 h to ensure complete reaction. The resulting precipitate contains nanostructured hydroxide of yttrium/zirconium.
After precipitation of the hydroxides are filtered and washed. The precipitate is then reasone and other undesirable by-products. Ion-exchange resin is removed by filtration through krupnogolovchaty filter, and then allocate the precipitate by filtration through melkopyatnistoy filter.
Nanostructured hydroxide of yttrium/zirconium then resuspended in distilled deionized water and treated with ultrasound using intense ultrasound probe (output power 550 W, length 15 cm, diameter 2.5 cm). This processing is an important stage of the technology, as it destroys aggregates of powder and introduces defects into the lattice of nanostructured particles. And desagglomeration, and the existence of surface defects are important for influencing the behavior of the active material of the Nickel electrode.
At least one surface-active agent, such as ethanol, then add to the particles of the hydroxide to provide the minimum aggregation of particles during further heat treatment. The heat treatment is carried out in air at temperatures in the range of from about 200oWith up to approximately 800oIn order to obtain nanostructured powder Y2ABOUT3/Zr2.
Nanostructured powder is then suspended in a solution of polyvinyl alcohol (PVA) in water, where the amount of PVA is 3-12% weight in the spray-dried, to form a nanoporous spherical powder agglomerates having diameters in the range of from about 1 to 200 μm, and each agglomerate is a lot of nanostructured grains Y2O3/Zr2. Spray drying to obtain particles in such a form provides further handling and transformation of the powder, for example, it improves the uniformity of the flow characteristics of agglomerated particles for use in thermal spraying.
X-ray diffraction analysis of nanostructured powders, Y2O3/Zr2shows that the phase structure depends on the concentration of yttrium. Without the addition of yttrium obtained only monoclinic zirconium oxide. When yttrium concentration of 2.5 atomic percent powder contains both monoclinic and tetragonal phases, whereas yttrium concentration of 5 atomic % predominant tetragonal phase coexists with a small amount monoclinically phase. At 7% atomic yttrium cubic structure.
Morphological studies of nanostructured powders, Y2O3/ZrO2before spray drying with the use of IPE and NEVR show that nanostructured powders represent compound is obodno agglomerated into larger agglomerates, having a diameter less than about 500 nm. The direct examination of a lattice of individual nanoparticles under electron microscope high resolution shows that the distance between the planes of the crystal lattice in grain boundary is greater than in the interior of the grain. These images also show the existence of many of the surface steps. This phenomenon is extremely important for catalysts, because these partial surfaces are more energy and provide a high density of catalytic centers.
Although there have been shown and described preferred embodiments of the invention can be manufactured in various modifications and substitutions that do not violate the meaning and subject of the invention. Accordingly, it should be understood that the present invention is described for illustration and not for limitation.
1. The method of synthesis of nanostructured oxides and hydroxides, including the preparation of an aqueous starting solution and an aqueous solution of reagent; joint spraying an aqueous solution of the reagent in aqueous source solution and precipitation thereby powder nanostructured oxide or hydroxide of a mixture of aqueous starting solution and the aqueous reagent solution; heat treatment is different, however, that at least one aqueous starting solution and the aqueous reagent solution contains at least one water-soluble salt preceding nanostructured oxide or hydroxide.
3. The method according to p. 2, characterized in that the water-soluble preceding salt is a salt of the metal or rare earth salt.
4. The method according to p. 3, characterized in that the water-soluble preceding salt is at least one of Nickel salts, manganese salts, salts of yttrium, zirconium salts, aluminum salts, salts of silicon, magnesium salts, cobalt salts, and salts of vanadium, salts of molybdenum, zinc salts, copper salts, titanium salts, iron salts, salts of tungsten or salts of rare earth metals.
5. The method according to p. 3, wherein the water soluble salt is Ni(NO3)2, With NISO4, NiC12, MnSO4, KMnO4, NaMnO4, LiMnO4, US3, ZrOCl2With(NO3)2or A1(NO3)3.
6. The method according to p. 1, characterized in that at least one aqueous starting solution or aqueous reagent solution contains an oxidizing agent, acid or base.
7. The method according to p. 1, wherein the heat treatment is the EF of the second structure.
8. The method according to p. 1, wherein the heat treatment is carried out in the temperature range from about 60 to 800oC.
9. The method according to p. 1, wherein after the heat treatment and treatment with ultrasound nanostructured oxide or hydroxide is subjected to spray drying, thereby forming a nanostructured agglomerates having a diameter in the range from about 0.1 up to 200.0 microns.
10. The method according to p. 1, characterized in that the nanostructured oxide or hydroxide is at least one of the oxides or hydroxides of Nickel, manganese, yttrium, zirconium, aluminum, silicon, magnesium, cobalt, vanadium, molybdenum, zinc, silver, titanium, iron, copper, tungsten or rare earth metals.
11. The method according to p. 1, characterized in that the nanostructured oxide or hydroxide comprises Nickel hydroxide, a hydroxide of Nickel, alloy of at least one of aluminum, cobalt, cadmium, manganese or zinc, manganese hydroxide, manganese hydroxide, alloy of at least one of cobalt, iron or platinum, yttrium oxide, zirconium oxide or yttrium-stabilized Zirconia.
12. The method according to p. 1, characterized in that stage thermal processing executed by CIS or hydroxide comprises Nickel hydroxide or manganese hydroxide.
14. The method according to p. 1, characterized in that stage ultrasonic treatment is carried out until the stage of heat treatment.
15. The method according to p. 14, characterized in that the nanostructured oxide or hydroxide comprises yttrium oxide, zirconium oxide or a combination thereof.
16. Nanostructured oxide or hydroxide synthesized according to the method of p. 1.
17. Nanostructured oxide or hydroxide under item 16, characterized in that the nanostructured oxide or hydroxide is an oxide or hydroxide of Nickel, manganese, yttrium, zirconium, aluminum, silicon, magnesium, cobalt, vanadium, molybdenum, zinc, silver, titanium, iron, cobalt, copper, tungsten or rare earth metals.
18. Nanostructured oxide or hydroxide under item 16, characterized in that the nanostructured oxide or hydroxide is a hydroxide of Nickel hydroxide Nickel, alloy of at least one metal selected from aluminum, cobalt, cadmium, manganese or zinc, manganese oxide, manganese oxide, an alloy of at least one metal selected from cobalt, iron or platinum, yttrium oxide, zirconium oxide or yttrium-stabilized Zirconia.
19. Nanostructured oxide or hydroo the con, where nanostructured fibers have diameters less than about 100 nm.
20. Nanostructured oxide or hydroxide under item 19, characterized in that the fibers have diameters less than about 50 nm.
21. Nanostructured oxide or hydroxide under item 19, characterized in that the nanostructured fibers have a size of more than about 10.
22. Nanostructured oxide or hydroxide under item 19, characterized in that the nanostructured fibers are separated from each other at a distance of about 0.5 to 200.0 nm.
23. Nanostructured oxide or hydroxide under item 22, wherein the nanostructured fibers are separated from each other at a distance of approximately 5-50 nm.
24. Nanostructured oxide or hydroxide under item 19, characterized in that the porosity of the Assembly of nanostructured fibers is greater than about 60 about. %.
25. Nanostructured oxide or hydroxide on p. 24, characterized in that the porosity of the Assembly of nanostructured fibers is greater than about 80 about. %.
26. Nanostructured oxide or hydroxide under item 19, characterized in that it contains, in addition, nanostructured particles, where nanostructured particles have diameters less than about 100 nm.
27. Nanostruc is up to 100 nm.
28. Nanostructured oxide or hydroxide under item 27, wherein the nanostructured particles are present in the form of agglomerates, where the agglomerates have diameters of from about 0.1 to 200,0 mm.
29. Nanostructured oxide or hydroxide on p. 28, characterized in that the agglomerates are porous, and the pores have diameters in the range of from about 0.5 to 20.0 nm.
30. Nanostructured oxide or hydroxide on p. 25, characterized in that the agglomerates of nanostructured particles comprise from about 60 to 90% of the total volume of nanostructured oxide or hydroxide.
31. Nanostructured oxide or hydroxide under item 19, comprising oxide or hydroxide of Nickel, manganese, yttrium, zirconium, aluminum, silicon, magnesium, cobalt, vanadium, molybdenum, zinc, silver, titanium, iron, copper, tungsten and other rare earth metals or combinations thereof.
32. Nanostructured oxide or hydroxide under item 19, comprising manganese dioxide or Nickel hydroxide.
33. Composition comprising a hydroxide of Nickel, characterized in that the particles or fibers of Nickel hydroxide have a diameter of less than about 100 nm.
34. The composition according to p. 33, characterized in that the nanostructured hydroxide neither is our least one metal is cobalt, the aluminum, platinum, copper, titanium, tungsten, alkaline metal, a noble metal or semi-conducting metal.
36. Composition comprising dispersed nanostructured or fibrous manganese dioxide, characterized in that the particles or fibers of manganese dioxide have a diameter of less than about 100 nm.
37. The composition according to p. 36, characterized in that the nanostructured manganese dioxide doped with at least one metal.
38. The composition according to p. 37, wherein the at least one metal is a cobalt, aluminum, platinum, copper, titanium, tungsten, alkaline metal, a noble metal or semi-metal.
39. Composition comprising dispersed nanostructured or fibrous zirconium oxide, wherein the particles or fibers of Zirconia have a diameter of less than about 100 nm.
40. The composition according to p. 39, characterized in that the nanostructured zirconium oxide contains, in addition, nanostructured oxide of yttrium.
41. Nanostructured composite materials, characterized in that they comprise at least one Assembly of nanostructured fibers, where nanostructured fibers have diameters less than prima is greater as one Assembly, where nanostructured particles have diameters less than about 100 nm.
42. Nanostructured composite materials p. 41, characterized in that the nanostructured fibers have a size greater than about 10.
43. Nanostructured composite materials p. 41, characterized in that the nanostructured fibers are separated from each other at a distance of about 0.5 to 200.0 nm.
44. Nanostructured composite materials p. 43, characterized in that the nanostructured fibers are separated from each other at a distance of approximately 5-50 nm.
45. Nanostructured composite materials p. 41, characterized in that the porosity of the at least one nanostructure Assembly of fibers is greater than about 60 about. %.
47. Nanostructured composite materials p. 41, characterized in that the agglomerates of nanostructured particles have diameters of from about 0.1 to 200,0 mm.
48. Nanostructured composite materials p. 41, characterized in that the agglomerates of nanostructured particles comprise about 60-90% is to be so, that include oxide or hydroxide of Nickel, manganese, yttrium, zirconium, aluminum, silicon, magnesium, cobalt, vanadium, molybdenum, zinc, silver, titanium, iron, copper, tungsten or other rare earth metals.
50. Nanostructured composite materials p. 41 consisting of manganese dioxide or Nickel hydroxide.
51. Nanostructured composite materials p. 41, characterized in that the composites have a high rate of percolation and high density of active sites.
52. Nanostructured composite materials, characterized in that they comprise at least one Assembly of nanostructured fibers, where nanostructured fibers have diameters less than about 100 nm, and nanostructured particles adjacent to, or partially or completely with at least one Assembly, where nanostructured particles have diameters less than about 100 nm.
55. the other at a distance of approximately 5-50 nm.
59. Nanostructured composite materials, characterized in that they contain at least one Assembly of nanostructured fibers, where nanostructured fibers have diameters less than 100 nm.
62. Nanostructured composite materials p. 59, characterized in that the nanostructured dies are separated from each other at a distance of approximately 5-50 nm.
63. N is tournoi Assembly of fibers more than about 60 about. %.
66. Nanostructured composite materials p. 59, comprising the oxide or hydroxide of Nickel, manganese, yttrium, zirconium, aluminum, silicon, magnesium, cobalt, vanadium, molybdenum, zinc, silver, titanium, iron, copper, tungsten and other rare earth metals, or combinations thereof.
Priority points:
18.11.1996 on PP. 1-8, 10-20, 22, 26, 29, 31-41, 43, 49-52, 54, 59, 61 and 66;
22.11.1996 on PP. 9, 21, 24-25, 28, 42, 45-48, 53, 56-58, 60, 63-65;
05.03.1997 on PP. 23, 27, 30, 44, 55 and 62.
The method of obtaining spherical hydrate of oxide of nickel // 2193014
The invention relates to ferrous metallurgy and can be used to produce spherical hydrate of oxide of Nickel used in the battery industry
The way hydroxide nickel (ii) // 2191160
The invention relates to the field of production of Nickel compounds, hydroxides, and can be used in the manufacture of alkaline batteries
The method of obtaining spherical hydrate of oxide of nickel and device for its implementation // 2188161
The invention relates to the field of hydrometallurgy of non-ferrous metals and can be used to produce spherical hydrate of oxide of Nickel, used in the manufacture of batteries
The invention relates to the field of producing compounds of Nickel, in particular to technology hydroxide Nickel (II) used for current sources, for example, in the composition of the active mass of the positive electrodes of alkaline batteries
The method of obtaining insoluble hydroxides of metals // 2143997
A method of producing nickel (ii) hydroxide // 2138447
The invention relates to methods for inorganic compounds, in particular to methods for Nickel (II) hydroxide used in the electrical industry for the production of alkaline batteries
The method of obtaining individual and complex metal oxides // 2047556
The invention relates to inorganic chemistry, and in particular to methods for producing metal oxide, and can be used to obtain pigments, catalysts, semiconductor materials
The method of obtaining basic carbonate salts of copper, zinc, nickel and cobalt and their oxides // 2043301
The invention relates to the technology for basic carbonate salts of copper, zinc, Nickel and cobalt and their oxides, which can be used as raw materials and intermediates in the production of catalysts and absorbents in the chemical and petrochemical industry
A method of producing nickel oxide // 2036154
The invention relates to chemical production of oxides of Nickel, used in various industries to obtain ferrites, catalysts, pigments in paints for glass etc
A method of producing manganese dioxide // 2193527
The invention relates to the field of production of manganese dioxide, in particular electrolytic synthesis methods
The method of extraction of manganese from manganese ores // 2176679
The invention relates to the extraction of useful components hydrometallurgical methods
The method of processing of manganese ores // 2175991
The invention relates to ferrous metallurgy and can be used in the hydrometallurgical processing of manganese ore to concentrate manganese various purposes
The invention relates to hydrometallurgy manganese and can be used to obtain active manganese dioxide from poor carbonate manganese ores
The method of producing oxide of lithium and manganese li8mn2o4-5with the spinel structure (options) and secondary rechargeable battery // 2165390
The invention relates to a method for producing a compound oxide of lithium and manganese with a spinel structure and its use in secondary batteries
A method of producing manganese dioxide gamma-modification // 2149832
The invention relates to a process of obtaining manganese dioxide gamma-modification and can be used for the manufacture of cathode mass of chemical current sources of manganese-zinc systems
Method for production of electrolytic manganese dioxide // 2141009
The invention relates to inorganic chemistry and can be used in particular for the preparation of the catalyst used for purification of gas mixtures of carbon monoxide in the systems of collective and individual protection of respiratory organs in the emissions of industrial enterprises, for purification of exhaust gases of internal combustion engines, as well as for other industrial and environmental purposes
A method of producing manganese dioxide active in the oxidation of carbon monoxide // 2136597
The invention relates to the field of inorganic chemistry and can be used in particular for the preparation of the catalyst used for purification of gas mixtures of carbon monoxide in the systems of collective and individual protection of respiratory organs and the emissions of industrial enterprises, for purification of exhaust gases of internal combustion engines, as well as for other industrial and environmental purposes
The invention relates to the field of inorganic chemistry and can be used in particular for the preparation of the catalyst used for purification of gas mixtures of carbon monoxide
Synthetic macnalty product (variants) and a method of its manufacture // 2155710
The invention relates to synthetic maxprice product and method of its production
The method of co-precipitation of metal hydroxides to obtain a piezoelectric ceramic material based on lead zirconate-titanate // 2042629
The invention relates to chemical technology and can be used for piezoelectric ceramic materials based on lead zirconate titanate (CTS) and products from them


The organization deeply regrets this failure of human rights leadership at the highest levels of government in the USA.
'President George W. Bush's record on the death penalty is well-known across the world,' Amnesty International said, recalling the 152 state executions that took place during his five-year governorship of Texas - many of them in violation of international standards.
'By refusing to step in and impose a moratorium on federal executions, he has further damaged his and his country's reputation,' Amnesty International said.
The case of Timothy McVeigh presented the government with the opportunity to announce to the widest possible audience that it would no longer support a policy that allows the murderer to set society's moral tone by imitating what it seeks to condemn.
'The level of public scrutiny in the McVeigh case has merely served to highlight the relative silence accompanying the 716 other non-federal executions carried out in the USA since 1977,' Amnesty International said, drawing attention to the planned execution of another federal prisoner, Juan Raul Garza, scheduled for next Tuesday.
'With the Garza case, the US government's attitude to its international obligations will be once again in the spotlight,' Amnesty International said. The organization stressed how the US government has so far failed to explain satisfactorily the widespread geographic and racial disparities in federal capital sentencing - issues of direct relevance to the Garza case - and how the Inter-American Commission on Human Rights has called for the execution to be halted, saying it will violate international law because of unfair trial issues.
'The international community must redouble its efforts to persuade the US Government to impose a moratorium on federal executions as a first step towards leading its country to abolition,' Amnesty International said.


Quite a week in my hometown. On Tuesday, ESPN commentator Kirk Herbstreit answered questions friend of Rusty John Asher at a charity luncheon for Catholic schools held in conjunction with the Trinity-St. X football game on Friday. Herbstreit said he's a regular at the Derby, which Asher reminded us is only 214 days away.
It was the start of the Idea Festival, where Angie Fenton hosted a session called Thrivals targeting young adults. I stopped in and heard several high school students ask intelligent questions about what will be different in 2035. One young man named Thomas was from Fern Creek High School, and his concern was about light pollution and how we can't see the stars at night in cities. As he was speaking, I got a text alert from a news station that his school was on lockdown after a shooting.
Later, at Louisville Collegiate School, the writer Carl Hiaasen spoke about his book, "Skink-No Surrender". In conjunction with the appearance, Carmichaels Bookstore invited the Louisville Zoo to bring along some actual skinks. Now I don't know much about lizards and skinks and reptiles of any sort, but I did get to see the slimy creature below up close. Hiaasen talked about his approach to writing, saying that he doesn't do outlines and just lets the characters and stories go where his mind takes them. He credited the real life weirdness of Floridians for inspiring the strange actions his characters sometimes take, and took questions from a mix of the old and young among the several hundred book-lovers who showed up.
As Carl spun tales about the real-life criminal mind that inhabits the Sunshine State and inspires his novels, I couldn't help but think about how, well, we've got enough goofballs around here who break the law in strange ways, plus corrupt politicians and even some people who manage to do the right thing, that I ought to write a similar book featuring Kentuckians. I'll put that on the list.
Be the first to comment on "Highs and Lows on Tuesday: Herbstreit, a Festival of Ideas and Meeting a Reptile"


A skydiver narrowly avoided death after suffering a seizure midway through a parachute jump.
The man, identified only as Christopher, said he was doing stage five of the Accelerated Free Fall programme when he had a 'near-death experience' – he had a seizure and lost consciousness as he plunged towards the ground.
But he was spared a grisly fate when his jumpmaster caught up with him and pulled his ripcord, releasing his parachute.
'At around 9000ft I have a seizure while attempting a left hand turn,' he wrote.
'I then spend the next 30 seconds in free fall unconscious.
Thankfully my jumpmaster manages to pull my ripcord at around 4000ft. I become conscious at 3000 ft and land safely back to the ground.


text:
El Generali Ladies Linz 2015 es un torneo de tenis que se juega en canchas duras bajo techo. Es la 29ª edición de la Generali Ladies Linz, y es parte de los torneos internacionales de la WTA Tour de 2015. Se llevará a cabo en Linz, Austria, del 12 de octubre el 18 de octubre de 2015.

Cabezas de serie

Individual Femenino

 Ranking del 5 de octubre de 2015

Dobles femeninos

Campeonas

Individual femenino

 Anastasiya Pavliuchenkova venció a  Anna-Lena Friedsam por 6-4, 6-3

Dobles femenino

 Raquel Kops-Jones /  Abigail Spears vencieron a  Andrea Hlaváčková /  Lucie Hradecká por 6-3, 7-5

Referencias

Enlaces externos
 Sitio oficial

Torneo de Linz 2015

redpajama_set_name: RedPajamaWikipedia


A Newcastle man died in a crash west of the town on Saturday evening, according to a news release from the Wyoming Highway Patrol on Monday.
George Thompson, 27, was driving a pickup eastbound about seven miles east of Newcastle on U.S. Highway 16, when at 7 p.m. it left the highway to the south and was overcorrected to the left, according to the news release from Patrol Sgt. David Wagener.
The overcorrection caused the pickup to travel over the center line of the highway. It then overcorrected to the right. That sent the pickup into a skid and it exited the highway to the south. After leaving the highway, it tripped and rolled multiple times.
The seat belt system in the pickup had been completely removed at some point before the crash. Thompson was was ejected from the pickup and died at the scene.
The Highway Patrol is investigating suspected alcohol use, excessive speed and lack of seat belt use as contributing factors in this crash.
This marked the 48th highway fatality in Wyoming for 2016, compared to 74 fatalities during this same time a year ago.


text:
Kaye Kessler Passes
January 20, 2022:
Kaye Kessler, 97, a former reporter for the Columbus Citizen (later Citizen-Journal) who had the present longest membership in the United States Harness Writers Association at 66 years, passed away December 9, 2021 in Littleton, Colorado....read on
Trot Insider has learned that Canadian Hall of Fame horseman William 'Bud' Fritz of Walkerton, Ont. passed away peacefully at McVean Lodge, Hanover on Tuesday, Jan. 18 at the age of 86....read on
Anna Ewen Passes
Longtime Standardbred industry participant Anna Ewen passed away peacefully on Wednesday, Jan. 12, at the age of 83....read on
Longtime Ontario horseman Dave 'Garney' Gibson passed away suddenly on Tuesday, Jan. 18. He would have turned 64 on January 19, 2022....read on
Kenneth L. Middleton Passes
Western New York horseman Kenneth L. Middleton, age 77, of Mount Morris, New York, passed away on Wednesday, Jan. 12 at Wyoming County Community Hospital in Warsaw, New York....read on
Elwood L. Clark Passes
Elwood L. Clark, 87, passed away Sunday, Jan. 9. Clark was born and raised in Lockport, New York, the son of the late James and Edna (Brown) Clark. He resided on his horse farm in Corfu, New York for 35 years and later in life retired in Naples, Florida....read on
Julian Bertozzi Passes
Longtime harness racing industry participant Julian Bertozzi of Burlington, Ont. passed away peacefully on January 9, 2022 in his 83rd year....read on
Amos Finch Passes
Amos Frederick Finch, 85, of Walton, N.Y. passed away on Tuesday, January 11, 2022 at home with his wife by his side after a two-year battle with various health problems....read on
Ab Gilmour Passes
Former horseman Ab Gilmour of RR 2 Ailsa Craig, Ont. passed away peacefully at Mitchell Nursing Home on Sunday, Jan. 9, at the age of 91....read on
Patrick McLead Passes
Patrick Jay McLead, 74, of Delaware passed away peacefully late Sunday evening, Jan. 9, at the Delaware Court Health Care Center in Delaware surrounded by his loving family....read on
Marlene Taylor Passes
January 6, 2022:
Longtime Standardbred owner Marlene Taylor of Philadelphia, Pa. passed away on Wednesday, Jan. 5, 2022 at the age of 63....read on
Dorothy Peters Passes
Longtime Standardbred Canada member and former owner Dorothy Marie Peters of Erin, Ont. passed away on the morning of January 4 at the age of 90....read on
Arthur 'Joe' Jones Passes
Longtime horseman Arthur "Joe" Jones of Denfield, Ont. passed away at St. Mary's Memorial Hospital on Friday, Dec. 31, 2021, at the age of 85....read on
Conrad 'Conny' Leber Passes
Longtime Standardbred owner Conrad Leber of Montreal, Que. passed away on January 1, 2022, at the age of 96 years old, surrounded by his adoring family....read on
Carl MacArthur Passes
December 29, 2021:
Former Standardbred trainer and driver Carl MacArthur of Brampton, Ont. passed away on Saturday, Dec. 25 at his home with family. He was 87....read on

redpajama_set_name: RedPajamaCommonCrawl


Sweetcorn fritters are perfect for breakfast, brunch, lunch and dinner − or make mini versions as finger food for a party.
1. Sift the flour, baking powder, cumin or coriander, salt and pepper into a bowl and make a well in the centre.
2. Mix together the eggs, Wattie's Bit On The Side Sweet Chilli Sauce, water, Wattie's frozen Supersweet Corn and coriander or parsley and stir into the flour gently.
3. Heat a knob of butter in the frying pan and when hot cook about 2-3 tablespoons of the mixture at a time. Once the bubbles form on the top of the corn cake, flip and cook the other side for a further 2 minutes or until cooked and tender.
Serve with grilled bacon, sliced avocado, sour cream and extra Wattie's Bit On The Side Sweet Chilli Sauce.
oh so yummy as a brunch option with salad on the weekend!!
Served these with a tomato and onion savoury and everybody raved. The fritters are a good size and tasty.
I have used this recipe so many times. Excellent !!
I use chuck wagon corn, only 2 tblsp sweet chilli sauce, grated parmisan cheese, 1/2 cup, yum.


text:
Q: eigenvector bug? Bug introduced in 7.0.1 or earlier and fixed in 10.0.0

I have a fairly simple $3\times3$ complex matrix,
$$
M=\left(
\begin{array}{ccc}
 \frac{7}{2}-\frac{i}{2} & -1+i & \frac{1}{2}+\frac{5 i}{2} \\
 -1+i & 5+i & -1+i \\
 \frac{1}{2}+\frac{5 i}{2} & -1+i & \frac{7}{2}-\frac{i}{2} \\
\end{array}
\right)
$$
Solving for the eigenvalues and eigenvectors:
mat = {{7/2 - I/2, -1 + I, 1/2 + 5 I/2}, {-1 + I,
    5 + I, -1 + I}, {1/2 + 5 I/2, -1 + I, 7/2 - I/2}};
{vals, vecs} = Eigensystem[mat]

gives (Mathematica 9.0.1)
\begin{array}{ccc}
 6 & 3+3 i & 3-3 i \\
 \{1,-2,1\} & \left\{\frac{17}{13}+\frac{6 i}{13},0,1\right\} & \{-1,0,1\} \\
\end{array}
But that 2nd eigenvector is not right; it should be $(1,1,1)$.   Is there a bug, or am I being incredibly obtuse?

A: This bug has been fixed in V10
mat = {{7/2 - I/2, -1 + I, 1/2 + 5 I/2}, {-1 + I,
    5 + I, -1 + I}, {1/2 + 5 I/2, -1 + I, 7/2 - I/2}};

Eigensystem[mat]

Gives:
{{6, 3 + 3 I, 3 - 3 I}, {{1, -2, 1}, {1, 1, 1}, {-1, 0, 1}}}

\begin{array}{ccc}
 6 & 3+3 i & 3-3 i \\
 \{1,-2,1\} & \left\{1,1,1\right\} & \{-1,0,1\} \\
\end{array}

A: This appears to be a genuine bug with exact arithmetic in Eigensystem. Here is a comparison to the same calculation with real numbers, for which I use the matrix mat//N:
mat = {{7/2 - I/2, -1 + I, 1/2 + 5 I/2}, {-1 + I,
    5 + I, -1 + I}, {1/2 + 5 I/2, -1 + I, 7/2 - I/2}};

{vals, vecs} = Eigensystem[mat]

(*
==> {{6, 3 + 3 I,
  3 - 3 I}, {{1, -2, 1}, {17/13 + (6 I)/13, 0, 1}, {-1, 0, 1}}}
*)

{numericvals, numericvecs} = Eigensystem[mat // N] // Chop

(*
==> {{6., 3. - 3. I,
  3. + 3. I}, {{-0.408248, 0.816497, -0.408248}, {-0.707107, 0,
   0.707107}, {0.57735, 0.57735, 0.57735}}}
*)

The results are not equivalent, and I can test which of them gives correct eigenvalues as follows:
Table[Chop[mat.vecs[[i]] - vals[[i]] vecs[[i]]], {i, 3}]

(*
==> {{0, 0, 0}, {36/13 - (24 I)/13, -(36/13) + (24 I)/13, 0}, {0,
   0, 0}}
*)

Table[
 Chop[N[mat].numericvecs[[i]] -
   numericvals[[i]] numericvecs[[i]]], {i, 3}]

(* ==> {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}} *)

Clearly, the floating-point result is correct and the exact arithmetic result (using mat without N) is incorrect.
This then also indicates how to work around this bug: use only numerical matrices with N[...].

redpajama_set_name: RedPajamaStackExchange