Abstract: A floor tile system for placing on an ice surface includes a plurality of flexibly interconnected tiles. Each tile includes a tile body that is integrally formed of thermally insulative material, including upstanding supports having a height selected to provide a temperature gradient between the ice surface and the top surface of the tile sufficient to substantially prevent condensation on the top surface when surrounded by typical ice rink ambient conditions of temperature and humidity.

Abstract: Phosphor lag was reduced to acceptable levels in high lag monoclinic M' yttrium tantalate x-ray phosphors through the addition of minor amounts europium to the phosphors. In particular, europium was added to yttrium tantalate phosphors containing terbium and to phosphors formulated with a stoichiometric excess of yttrium.

Abstract: A pure gamma calcium pyrophosphate for use in e.g., the production of calcium haloapatite fluorescent phosphor host materials, and a process for the synthesis thereof. Dicalcium orthophosphate is dissolved in a dilute solution of nitric acid in water, and spray-dried to form a calcium phosphate powder including a major phase of spherically shaped particles of dicalcium orthophosphate. The calcium phosphate powder is fired in air to convert the calcium phosphate powder to pure gamma calcium pyrophosphate. Gamma pyrophosphate will not undergo dehydration during firing of the fluorescent phosphor; thus larger quantities of phosphor can be processed in a firing vessel.

Abstract: A process for producing a manganese activated zinc orthosilicate phosphor. An aqueous dispersion is prepared including fumed silica having an ultrafine average particle size of less than 50 nm, a zinc precursor, and a manganese precursor. The molar ratio of zinc:silicon in the dispersion is approximately 1.3:1 to 2.0:1, and the molar ratio of manganese in the dispersion is sufficient to activate the phosphor. The precipitate from the dispersion is calcined in an inert atmosphere at a temperature and for a time sufficient to form a manganese activated zinc silicate phosphor having a broad band emission peaking in the green region of the visible spectrum when stimulated by external radiation at approximately 254 nm. The calcined phosphor may be milled to achieve an average particle size of less than 5 .mu.m, the milling step being performed without significant loss of plaque brightness. Also disclosed is a green emitting manganese activated zinc silicate phosphor having an average particle size of less than 5 .

Abstract: A process for producing a manganese and lead activated calcium metasilicate phosphor having the nominal formula CaSiO.sub.3 :MN:Pb. The process involves preparing a uniform aqueous dispersion of fumed silica having an ultrafine average particle size of less than 50 nm, a calcium precursor, a manganese precursor, and a lead precursor. Preferably, the calcium, manganese, and lead precursors are added as powders to an aqueous dispersion of said ultrafine fumed silica. The ultrafine fumed silica aqueous dispersion is heated to a temperature of about 50.degree.-90.degree. C. and the powders are mechanically dispersed in the fumed silica aqueous dispersion to form the uniform aqueous dispersion. The molar ratio of calcium:silicon in the mixture is approximately stoichiometric to 1.3:1; and the molar ratios of manganese and lead in the dispersion are sufficient to activate the phosphor. The precipitate from the dispersion is calcined at a temperature of about 1050.degree.-1135.degree. C.

Abstract: A method of making lead-activated barium silicate phosphor involves the use of a lead source which is not lead oxide. More particularly, the lead source may be lead silicate or lead carbonate-lead hydroxide.