摘要:
Crystals of lithium niobate and lithium tantalate are preconditioned to intentionally increase their electrical conductivity, thus providing crystals with an increased ability to reduced surface charging. Reducing surface charging reduces the risk that the crystals may catastrophically discharge, and adversely affect the performance of devices in which the crystal is incorporated.
摘要:
A process for producing valve metal oxides, such as tantalum pentoxide or niobium pentoxide with a narrow particle size distribution within a desired particle size range. Valve metal solution from digestion of valve metal material containing ore is processed under controlled temperature, pH, and residence time conditions to produce the valve metal pentoxide and pentoxide hydrates. Also, disclosed are new tantalum pentoxide and niobium pentoxide products and new tantalum pentoxide precursors and niobium pentoxide precursors.
摘要:
This invention relates to azirconium hydroxideor zirconium oxide comprising, on an oxide basis, up to 30wt% of a dopant comprising one or more of silicon, sulphate, phosphate, tungsten, niobium, aluminium, molybdenum, titanium or tin, and having acid sites, wherein the majority of the acid sites are Lewis acid sites. In addition, the invention relates to a catalyst, catalyst support or precursor, binder, functional binder, coating or sorbent comprising the zirconium hydroxide or zirconium oxide. The invention also relates to a process for preparing zirconium hydroxide, the process comprising the steps of:(a) dissolving a zirconium salt in an aqueous acid, (b) addingone or more complexing agents to the resulting solution or sol, the one or more complexing agents being an organic compound comprising at least one of the following functional groups: an amine, an organosulphate, a sulphonate, a hydroxyl, an ether or a carboxylic acid group,(c)heating the solution or sol formed in step (b), (d) adding a sulphating agent, and(e) adding a base to form a zirconium hydroxide, and(f) optionally adding a dopant.
摘要:
The present invention is in the field of processes for the production of tantalum oxide particles. In particular the present invention relates to a process for producing crystalline tantalum oxide nanoparticles comprising heating a water-free solution containing (a) a tantalum alkoxide, (b) an acid, and (c) a solvent.