Abstract: Polycrystalline materials of macroscopic size exhibiting Single-Crystal-Like properties are formed from a plurality of Single-Crystal Particles, having Self-Aligning morphologies and optionally ling morphology, bonded together and aligned along at least one, and up to three, crystallographic directions.

Abstract: A method of sulfidation removal of zinc using hydrogen sulfide is provided, desirably at a temperature at 60° C. or lower, wherein in a container that is pressurized at 0.1 MPa or less with respect to atmospheric pressure, by making the pH of the solution 1.5 to 4.0, and the concentration of hydrogen sulfide in gas 2 volume % or greater in equilibrium with the hydrogen sulfide dissolved in the solution, the zinc in solution is removed by sulfidation to 1 mg/liter or less.

Abstract: A product and method for the removal of pollutant heavy metals from aqueous solutions which precludes the end user from storing, handling, feeding and controlling hazardous soluble sulfide materials. The product is a slurry which includes a mixture of a liquid medium and an essentially insoluble salt wherein the salt is the reaction product of heavy metal ions, preferably selected from Mn++ ions, Fe++ ions, and Fe+++ ions, and sulfide ions derived from soluble sulfide sources such as sodium sulfide, hydrogen sulfide, and sodium hydrosulfide. Addition of the subject slurry to a wastewater stream will effect the precipitation of heavy metals with lesser equilibrium sulfide ion concentrations than that of the essentially insoluble salt. Solids collected by this method may be returned to subsequent wastewater streams for additional removal of heavy metals by any excess heavy metal sulfide salt.

Abstract: A method of removing metallic mercury and ionic mercury from flue gases, especially of a power plant, is provided. A gas that contains sulfur dioxide, or other adequate amounts of sulfur in the form of H2S or COS, and a gas that contains hydrogen, are conveyed to a catalyzer for producing a gas that contains elemental sulfur and hydrogen sulfide. This gas is conveyed to flue gas upstream of a separator, wherein mercury in the flue gas reacts with the sulfur and ionic sulfur in the gas and is separated out in the separator.

Abstract: A product and method for the removal of pollutant heavy metals from aqueous solutions which precludes the end user from storing, handling, feeding and controlling hazardous soluble sulfide materials. The product is a slurry which includes a mixture of a liquid medium and an essentially insoluble salt wherein the salt is the reaction product of heavy metal ions, preferably selected from Mn++ ions, Fe++ ions, and Fe+++ ions, and sulfide ions derived from soluble sulfide sources such as sodium sulfide, hydrogen sulfide, and sodium hydrosulfide. Addition of the subject slurry to a wastewater stream will effect the precipitation of heavy metals with lesser equilibrium sulfide ion concentrations than that of the essentially insoluble salt. Solids collected by this method may be returned to subsequent wastewater streams for additional removal of heavy metals by any excess heavy metal sulfide salt.

Abstract: The present invention provides new compositions containing colloidal nanocrystals with high photoluminescence quantum yields, new synthetic methods for the preparation of highly luminescent colloidal nanocrystals, as well as methods to control the photoluminescent properties of colloidal nanocrystals. The new synthetic methods disclosed herein allow photoemission brightness (quantum yield) to be correlated with certain adjustable nanocrystal growth parameters associated with a given synthetic scheme.

Abstract: Chlorine and sulfide species are separately introduced to a flue gas passing through a scrubber in order to remove the elemental and oxidized mercury from the gas through the precipitation of mercuric sulfide at near 100% efficiency.

Abstract: Nanotubes of transition metal chalcogenides as long as 0.2-20 microns or more, perfect in shape and of high crystallinity, are synthesized from a transition metal material, e.g. the transition metal itself or a substance comprising a transition metal such as an oxide, water vapor and a H2X gas or H2 gas and X vapor, wherein X is S, Se or Te, by a two-step or three-step method including first producing nanoparticles of the transition metal as long as 0.3 microns, and then annealing in a mild reducing atmosphere of the aforementioned gas or gas mixture. The transition metal chalcogenide is preferably WS2 or WSe2. Tips for scanning probe microscopy can be prepared from said long transition metal chalcogenide nanotubes.

Abstract: A process of preparing an inorganic compound is disclosed, comprising the steps of (a) allowing at least an inorganic raw material compounds (A) and an inorganic raw material compound (B) which are different in solubility in water to react with each other in the presence of a reaction solvent with stirring to deposit an inorganic compound (C), while allowing a part of each of the compound (A) and compound (B) to exist as a solid; and

Abstract: Sulphides are prepared by combining a dithionite compound with an aqueous alkaline solution of an appropriate cation or mixture of cations. On heating the corresponding sulphides are precipitated. The dithionite compound may be a dithionite dianion which is produced as an intermediary when thiourea dioxide is used as a starting material in the solution. Examples of appropriate cations are zinc (as zinc acetate) and copper (as copper acetate). The precipitate is dried and subsequently fired to produce high quality sulphides which may be used as phosphors or other optoelectronic materials.

Abstract: A method for producing fine or ultra fine powder particles comprising mixing a metal alkoxide with a non-metallic hydride in an organic solvent, agitating the mixed solution, and then burning the mixed solution. The burning process comprises igniting the solution directly or burning the solution in situ. A self-sustaining flame will result. When the precursor solution burns, the metallic compound will be co-fired with the organic solvent. As a result, fine or ultra fine particles of mixed metal will burst from the flame, or thrust through the flame and be synthesized.

Abstract: This invention relates to a method for preparing a Zinc Sulfide powder, and provides a method for preparing a single crystalline powder of Zinc Sulfide (ZnS) a high crystallinity comprising a step of conducting a hydrothermal reaction of a) Zinc Oxide or Zinc acetate as Zinc source and b) thioacetamide or thiourea as Sulfur source at a temperature of 180 to 230° C. and a fluorescent substance using the same as a source.

Abstract: A method of manufacturing fine particles of the invention includes introducing a reactive gas flow containing a fine particle source material into a reactor from one side, growing fine particles in a gas phase by heating the fine particle source material in the reactive gas flow, introducing a diluting gas flow into the reactor from another side being almost counter-flow to the reactive gas flow, equalizing flow rates of the reactive gas flow and the diluting gas flow substantially with respect to a cross section of a flow channel, and then stopping growth of the fine particles by merging the reactive gas flow and the diluting gas flow.

Abstract: Shaped parts made of synthetic organic polymers have a good transparency in the range of visible light, good fire-proofing properties and a good remission from infrared radiation if they contain 1 to 45% by volume transparent zinc sulphide pigment with a mean particle size d50 in the range from 1 to 14 &mgr;m.

Abstract: The present invention is directed to a system and method for converting hazardous speciated and elemental mercury-containing wastes to environmentally acceptable wastes by mixing the wastes in the presence of a polysulfide, water, and an mercury-reactive material, such as elemental sulfur.

Abstract: A process for preparing a nanocrystalline material comprising at least a first ion and at least a second ion different from the first ion, and wherein at least the first ion is a metal ion, is described. The process comprises contacting a metal complex comprising the first ion and the second ion with a dispersing medium suitable to form the nanocrystalline material and wherein the dispersing medium is at a temperature to allow formation by pyrolysis of the nanocrystalline material when contacted with the metal complex.

Abstract: Sulphides and selenides are prepared by dissolving sulphur or selenium in an aqueous or non-aqueous solution of hydrazine hydrate. The solution is combined with a solution of an appropriate cation to precipitate the corresponding sulphide or selenide. Solutions of two or more cations may be used to produce ternary compounds of sulphur and selenium, for example thio-gallates. Likewise both sulphur and selenium can be used together to produce sulpho-selenides. The method is particularly applicable to the production of doped phosphors by the inclusion of solutions containing the appropriate dopant.

Abstract: The machinability of water-clear zinc sulfide articles produced by chemical vapor deposition and high temperature, high isostatic pressure (HIP) treatment is enhanced by extending the time over which the article is cooled following the HIP treatment. The resulting low stress, water-clear zinc sulfide articles can be more accurately finished/machined to precise shapes, such as are required in optical applications, than was previously possible.

Abstract: A process for preparing a nanocrystalline material comprising at least a first ion and at least a second ion different from the first ion, and wherein at least the first ion is a metal ion, is described. The process comprises contacting a metal complex comprising the first ion and the second ion with a dispersing medium suitable to form the nanocrystalline material and wherein the dispersing medium is at a temperature to allow formation by pyrolysis of the nanocrystalline material when contacted with the metal complex.

Abstract: Electroluminescent phosphor powders and a method for making phosphor powders. The phosphor powders have a small particle size, narrow particle size distribution and are substantially spherical. The method of the invention advantageously permits the economic production of such powders. The invention also relates to improved devices, such as electroluminescent display devices, incorporating the phosphor powders.