Abstract: Monophase crystalline mixed borates having the formula: M(II).sub.1-x Eu(II).sub.x M(III).sub.p Eu(III).sub.q Tb(III).sub.r B.sub.9 O.sub.16 wherein M(II) is at least one bivalent metal selected among barium, strontium, lead and calcium, it being understood that, in a given mixed borate, the lead and the calcium, together represent not more than 20% by moles based on the total number of moles of metals M(II); M(III) is a metal selected among lanthanum, gadolinium, yttrium, serium, lutetium and bismuth; x is a number higher or equal to zero and smaller than or equal to 0.2; p, q and r is different from zero; and the sum p+q+r equals 1; preparation method and luminescent composition containing them.

Abstract: Blue-luminescing lanthanum-gadolinium-oxybromide, activated by trivalent cerium, which oxybromide is also activated by trivalent terbium and is defined by the molecular formulaLa.sub.1-x-y-z Gd.sub.x Ce.sub.y Tb.sub.z OBr,in which0.25.ltoreq.x.ltoreq.1-y-z,0.002.ltoreq.y.ltoreq.0.05,0.0001.ltoreq.z.ltoreq.0.005 and y.ltoreq.z.

Abstract: A method of making a niobium activated yttrium tantalate x-ray phosphor using a lithium chloride-lithium sulfate eutectic flux is disclosed. The mole ratio of the flux is 46.5 mole percent lithium chloride to 53.5 mole percent lithium sulfate. Use of this flux improves phosphor brightness by up to 18%, reducing the x-ray dosage to the patient.

Abstract: The process of the invention is carried out in gaseous phase by the action of ammonia on the aqueous solutions of iron salts in an appropriate reacting vessels.

Abstract: A process is disclosed for preparing M' YTaO.sub.4 :Nb x-ray phosphor which comprises forming a uniform first mixture of Y.sub.2 O.sub.3, Ta.sub.2 O.sub.5, and Nb.sub.2 O.sub.5 in amounts equal to approximately the stoichiometric amounts to form the phosphor, milling with a flux of lithium chloride, the flux making up about 25% to 33% by weight of the mixture, firing the mixture in a furnace by heating to a temperature of about 1200.degree. C. to 1300.degree. C. at a heating rate of about 1.0.degree. C./minute to 1.5.degree. C./minute and maintaining the temperature for about 10 to 14 hours to react the components and produce a fired material containing luminescent material, cooling the material by turning off the heat and allowing the material to remain in the furnace until the temperature is no higher than about 300.degree. C., washing with deionized water, removing the wash water, drying, and classifying to obtain a -325 mesh particle size.

Abstract: Particles containing FeC are prepared by mixing (a) a boron compound or alkaline earth metal compound with (b) iron oxyhydroxide or iron oxide particles, or coating the former compound (a) to the latter particles (b), and then carburizing the mixture or coated particles with a carburizing agent.

Abstract: A process is disclosed for preparing M' YTaO.sub.4 :Nb X-ray phosphor which comprises forming a uniform first mixture of Y.sub.2 O.sub.3, Ta.sub.2 O.sub.5, and Nb.sub.2 O.sub.5 in amounts equal to approximately the stoichiometric amounts to form the phosphor, milling with deionized water as the milling fluid, removing the water, forming a uniform second mixture of the first mixture and a flux which can be lithium sulfate, lithium chloride or a mix of lithium sulfate and potassium sulfate in a mole ratio of 80 to 20, the flux making up about 25% to 50% by weight of the second mixture, firing the second mixture in a furnace by heating to a temperature of about 1200.degree. C. to 1300.degree. C. at a heating rate of about 1.0.degree. C./minute to 1.5.degree. C./min.

Abstract: A process is disclosed for preparing a single phase M'YTaO.sub.4 :Nb X-ray phosphor which comprises firing a uniform milled mixture consisting essentially of the components of Y.sub.2 O.sub.3, Ta.sub.2 O.sub.5, and Nb.sub.2 O.sub.5 in an amount equal to the stoichiometric amounts to form the phosphor, with a flux consisting essentially of lithium sulfate and potassium sulfate in a mole ratio of about 80 to 20, wherein the flux makes up from about 25% to about 50% by weight of the mixture. The firing is done by heating in a furnace to a temperature of from about 1200.degree. C. to about 1300.degree. C. at a heating rate of from about 1.0.degree. C. per minute to about 1.5.degree. C. per minute and maintaining the temperature for about 10 to 14 hours to react the components and produce a fired material containing luminescent material.

Abstract: A process is disclosed for producing M' phase YTaO.sub.4 :Nb X-ray phosphor which comprises forming a mixture of the components Y.sub.2 O.sub.3, Ta.sub.2 O.sub.5, and Nb.sub.2 O.sub.5, and a flux which can be lithium chloride, lithium sulfate or a mix of lithium sulfate and potassium sulfate in a mole ratio of 80 to 20, the flux making up about 25% to 50% by weight of the mixture, the components being provided in an amount equal to approximately the stoichiometric amounts to form the phosphor, firing the mixture in a furnace by heating to a temperature of about 1200.degree. C. to 1300.degree. C. at a heating rate of about 1.0.degree. C./min. to 1.5.degree. C./min. and maintaining the temperature for about 10 to 14 hours to react the components and produce a fired material containing luminescent material, cooling the material by turning off the heat to the furnace and allowing the material to remain in the furnace until the temperature is no higher than about 300.degree. C.

Abstract: Phosphors constituted by terbium and/or cerium activated lutetium-gadolinium-yttrium silicates have shown a high visible-light emission efficiency upon exposure to high energy radiation.Said phosphors are useful in the methods for recording and reproducing high energy radiation images.

Abstract: Luminescent terbium-activated alkaline earth metal rare earth metal borate having a monoclinic crystal structure and being defined by the formula M.sub.3 Ln.sub.1-x Tb.sub.x (BO.sub.3).sub.3 in which M is at least one of the elements Ba, Sr and Ca of which up to 34 mol % may be replaced by Mg, in which Ln is at least one of the elements La, Gd, Y and Sc and in which 0.005.ltoreq.x.ltoreq.1.

Abstract: A process is disclosed for producing M' phase YTaO.sub.4 :Nb X-ray phosphor which comprises forming a mixture of components Y.sub.2 O.sub.3, Ta.sub.2 O.sub.5, and Nb.sub.2 O.sub.5, and a flux which can be lithium chloride, lithium sulfate or a mix of lithium sulfate and potassium sulfate in an 80 to 20 mole ratio, the flux making up about 25% to 50% by weight of the mixture, the components being provided in stoichiometric amounts to form the phosphor, firing the mixture in a furnace by heating to a temperature of about 1200.degree. C. to 1300.degree. C. at a heating rate of about 1.0.degree. C./min. to 1.5.degree. C./min. and maintaining the temperature for about 10 to 14 hours to react the components and produce luminescent material, cooling the material by turning off the heat to the furnace and allowing the material to remain therein until the temperature is no higher than about 300.degree. C.

Abstract: A process is disclosed for producing a hydrolysis resistant rare-earth oxysulfide phosphor which comprises forming a uniform mixture of one or more rare earth oxides, sulfur, alkali carbonate, alkali phosphate, terbium oxide, and a zinc compound wherein the zinc compound is provided in an amount sufficient to result in a zinc concentration of from about 0.05% to about 1.0% by weight, heating the mixture in an air atmosphere in a covered vessel at a temperature of from about 900.degree. C. to about 1400.degree. C. for a sufficient time to form a terbium-activated rare-earth oxysulfide, washing the terbium-activated rare-earth oxysulfide with deionized water to remove essentially all of any water soluble impurities which are present, annealing the washed terbium-activated rare-earth oxysulfide in air at a temperature of from about 525.degree. C. to about 590.degree. C. for about 1 hour to about 3 hours to enhance the brightness of the phosphor.

Abstract: A manganese activated zinc silicate phosphor and method for producing same is disclosed which comprises dry blending a mixture of components consisting essentially of zinc oxide, silicic acid, a source of manganese, ammonium chloride, ammonium fluoride, tungstic oxide and silica wherein the Zn+Mn/Si mole ratio is from about 1.95 to about 2.02, wherein the silica is colloidal and has a surface area of from about 50 to about 410 m.sup.2 /g, and wherein the colloidal silica makes up from about 0.01% to about 1.0% by weight, firing the blend in a nitrogen atmosphere at a temperature of from about 1200.degree. C. to about 1300.degree. C. for a sufficient time to produce the phosphor, and firing the phosphor in air at a temperature of from about 1175.degree. C. to about 1275.degree. C. for a sufficient time to diffuse the tungsten and manganese to the surfaces of the phosphor particles. Between the firing steps, the phosphor can be milled for from about 60 to 120 minutes to increase luminescence.

Abstract: A cadmium-free cathodoluminescent phosphor composition consists essentially of zinc sulfide activated with from about 0.019% by weight to about 0.024% by weight of copper and from about 0.01% by weight of about 0.02% by weight of aluminum wherein the emission of the phosphor upon stimulation by cathode rays has CIE values of x of from 0.287 to 0.291 and y from 0.616 to 0.620. The process involves solid state heating of the various raw materials wherein a first relatively pure zinc sulfide and a second zinc sulfide containing chloride ions are mixed with the appropriate levels of and alkali metal chloride and sources of copper and aluminum activators and then heated in a nitrogen-carbon disulfide atmosphere for about 3 hours at 1775.degree. C. to about 1825.degree. C.

Abstract: An aluminum borate whisker having a composition of 9Al.sub.2 O.sub.3 .multidot.2B.sub.2 O.sub.3 or 2Al.sub.2 O.sub.3 .multidot.B.sub.2 O.sub.3 is formed by reacting under heating at least one aluminum-supplying component selected from the group consisting of hydroxides and inorganic salts of aluminum and at least one boric acid-supplying component selected from the group consisting of oxides, oxyacids and their alkali metal salts of boron in the presence of at least one flux selected from the group consisting of alkali metal chlorides, alkali metal sulfates and alkali carbonates.

Abstract: Hydrogen sulphide is removed from gas streams in rapid and efficient manner by oxidation to sulphur. The process is effected by intimately contacting the hydrogen sulphide in the gas stream with oxygen in an aqueous medium containing a hydrogen sulphide-oxidizing catalyst to effect oxidation of the hydrogen sulphide to sulphur, and transporting the sulphur particles to the surface of the aqueous medium. The sulphur particles collect on the surface of the aqueous medium and may be removed therefrom continuously or intermittently.

Abstract: A piezoelectric composite material prepared by compounding a ferroelectric ceramic powder comprising microcrystals having virtually single domains and a polymer. This composite has both the high piezoelectric property of the ferroelectric ceramic and the pliability of the polymer.

Abstract: Mixed lathanum-magnesium aluminates, their production process and lasers using these aluminates.These lasers comprise two flash lamps for longitudinally pumping a bar of an aluminate of formula La.sub.1-x Nd.sub.x Mg.sub.Y Al.sub.11 O.sub.18+y, x and y being numbers such that O<x.ltoreq.0.2 and O<y<1, preferably with y ranging from 0.5 to 0.55, emitting in the infrared, mirrors for amplifying the light emitted by the bar and a polarizing prism for passing the amplified light beam outside the laser.

Abstract: An emulsion acrylate copolymer is provided which unexpectedly is an effective magnetic binder inasmuch as it can be loaded with high amounts of one or more magnetic particles such as ferrite or ferrite containing materials to provide a flexible permanent type magnetic composition of high magnetic energy. The copolymer is made from an alkyl acrylate and a salt of 2-acrylamido-2-methylpropane sulfonic acid (AMPS). A carboxylated ethoxy alkyl phenol surfactant is utilized which provides good processability and permits a blend of the magnetic particles with the emulsion acrylate copolymer to be precipitated from a latex solution by high shear mixing. Flexible high magnetic energy magnets can thus be made and utilized in various applications such as refrigerator doors, electrical motors, and the like.