Abstract: A phosphor composition is disclosed containing a titanium free hafnium zirconium germanate phosphor which emits electromagnetic radiation principally in the spectral region to which silver halide exhibits native sensitivity. To maximize the intensity of emission the ratio of host metals satisifies the relationship:D.sub.1+x Ge.sub.1-xwhereD is the combined sum of zirconium and hafnium andx is 0.15 to -0.50.An X-ray intensifying screen is disclosed containing the phosphor composition.

Abstract: A process is disclosed of preparing a photographic emulsion containing tabular silver halide grains exhibiting a reduced degree of total grain dispersity. After forming a population of silver halide grain nuclei containing parallel twin planes, ripening out a portion of the silver halide grain nuclei. The silver halide grain nuclei containing parallel twin planes remaining are then grown to form tabular silver halide grains. The total grain dispersity of the emulsion is reduced by incorporating bromide ion in the dispersing medium prior to forming the silver halide grain nuclei and, at the time parallel twin planes are formed in the silver halide grain nuclei, a polyalkylene oxide block copolymer surfactant containing terminal hydrophilic alkylene oxide block units linked by a lipophilic alkylene oxide block unit accounting for at least 4 percent of the molecular weight of the copolymer.

Abstract: An optical article capable of modulating the reflection of polarized monochromatic electromagnetic radiation is disclosed comprised of a reflective metal layer, means acting as a support for directing the electromagnetic radiation to the reflective metal layer, an electrooptic medium that exhibits a refractive index which is a function of an applied electrical potential, and a counter electrode. At least one of the reflective metal layer and the counter electrode taking the form of laterally spaced segments. The reflective metal layer has a thickness of less than 0.5 .mu.m, and a dielectric layer having a thickness in the range of from 0.1 to 10 times the wavelength of the electromagnetic radiation and comprised of at least one metal oxide, metal fluoride, or low molecular weight aromatic compound is coated on the support. The electrooptic medium is a polymeric layer coated on the reflective metal layer exhibiting a second order polarization susceptibility greater than 10.sup.

Abstract: A process is disclosed of preparing a photographic emulsion containing tabular silver halide grains exhibiting a reduced degree of total grain dispersity. After forming a population of silver halide grain nuclei containing parallel twin planes, ripening out a portion of the silver haide grain nuclei. The silver halide grain nuclei containing parallel twin planes remaining are then grown to form tabular silver halide grains. The total grain dispersity of the emulsion is reduced by incorporating bromide ion in the dispersing medium prior to forming the silver halide grain nuclei and, at the time parallel twin planes are formed in the silver halide grain nuclei, a polyalkylene oxide block copolymer surfactant containing at least three terminal hydrophilic alkylene oxide block units each linked through a lipophilic alkylene oxide block linking unit accounting for at least 4 percent of the molecular weight of the copolymer.

Abstract: A process is disclosed of preparing a photographic emulsion containing tabular silver halide grains exhibiting a reduced degree of total grain dispersity. After forming a population of silver halide grain nuclei containing parallel twin planes, a portion of the silver halide grain nuclei are ripened out. The silver halide grain nuclei containing parallel twin planes remaining are then grown to form tabular silver halide grains. The total grain dispersity of the emulsion is reduced by incorporating bromide ion in the dispersing medium prior to forming the silver halide grain nuclei and, at the time parallel twin planes are formed in the silver halide grain nuclei, a grain dispersity reducing concentration of a polyalkylene oxide block copolymer surfactant is present comprised of two terminal lipophilic alkylene oxide block units linked by a hydrophilic alkylene oxide block unit accounting for at least 4 percent of the molecular weight of the copolymer.

Abstract: A process is disclosed of preparing a photographic emulsion containing tabular silver halide grains exhibiting a reduced degree of total grain dispersity. After forming a population of silver halide grain nuclei containing parallel twin planes, a portion of the silver halide grain nuclei are ripened out. The silver halide grain nuclei containing parallel twin planes remaining are then grown to form tabular silver halide grains. The total grain dispersity of the emulsion is reduced by incorporating bromide ion in the dispersing medium prior to forming the silver halide grain nuclei and, at the time parallel twin planes are formed in the silver halide grain nuclei, a polyalkylene oxide block copolymer surfactant containing at least three terminal lipophilic alkylene oxide block units each linked through a hydrophilic alkylene oxide block linking unit accounting for at least 4 percent of the molecular weight of the copolymer.

Abstract: An x-ray intensifying screen is disclosed containing magnesium tantalum niobium oxide as a phosphor in an ordered corundum crystalline form. In addition, small amounts of at least one alkali metal other than lithium can be present. Potassium, rubidium and cesium are each capable of increasing luminescence. The x-ray intensifying screens are useful in radiographic applications where it is important to reduce subject exposure to x-rays and also to create clear, sharp images.

Abstract: Photographic emulsions are disclosed comprised of radiation sensitive silver iodobromide grains, at least 50 percent of the total projected area of said silver iodobromide grains being accounted for by tabular grains exhibiting a mean tabularity of greater than 5, at least 10 percent of which are comprised of two opposed parallel major crystal faces, a host stratum having an iodide content of at least 4 mole percent, and laminar strata containing less than 2 mole percent iodide interposed between said host stratum and said opposed major crystal faces.The emulsions are characterized in that each of the laminar strata is comprised of a surface layer forming one of the major surfaces and having a thickness in the range of from 20 to 350 .ANG. and a subsurface layer located immediately beneath and in contact with the surface layer containing a hexacoordination complex of a Group VIII period 4 or 5 metal and at least three cyanide ligands.

Abstract: A cubic perovskite crystal structure is disclosed satisfying the unit cell formula:R.sub.0.33+z A.sub.0.67 C.sub.1-y O.sub.3-xwhereR, A and C represent rare earth, alkaline earth and copper atoms, respectively, capable of forming a superconductive R.sub.1 A.sub.2 C.sub.3 orthorhombic perovskite crystal structure;x is 0.67 to 1.0;y is up to 0.2; andz is up to 0.1.The crystal structure can be used to form superconductive superlattices and weak links for Josephson junction devices. The crystal structure can be produced by laser ablation deposition at a temperature below that required for the formation of a superconductive R.sub.1 A.sub.2 C.sub.3 orthorhombic perovskite crystal structure. The crystal structure can be used as a substrate for the subsequent deposition of an R.sub.1 A.sub.2 C.sub.3 orthorhombic perovskite crystal structure.

Abstract: A conductive film of crystalline bismuth mixed alkaline earth oxide containing silver is disclosed. A process for promoting the growth of crystalline bismuth mixed alkaline earth oxide grains by incorporating silver prior to sintering is also disclosed.

Abstract: A process is disclosed of diffusing a zinc dopant into a III-V compound substrate. To avoid degrading the substrate surface the zinc dopant source is provided by coating an organic composition comprised of a zinc organic compound chosen from the group consisting of zinc alcoholates, .beta.-diketonate chelates and carboxylate salts. The composition inludes at least one organic film-forming moiety containing from 5 to 30 carbon atoms.

Abstract: This invention is directed to a method of forming an article comprised of a substrate and an electrically conductive crystalline rare earth alkaline earth copper oxide thin film containing an R.sub.1 A.sub.2 C.sub.3 crystalline phase over an R.sub.2 A.sub.1 C.sub.1 crystalline phase, where R.sub.1 A.sub.1 and C represent rare earth, alkaline earth, and copper, respectively.

Abstract: A photorefractive system is disclosed containing interposed between electrodes an electrophotographic photoreceptor layer unit and a layer having a second order polarization susceptibility of greater than 10.sup.-9 electrostatic units comprised of organic polar aligned noncentrosymmetric molecular dipoles having an electron donor moiety linked through a conjugated .pi. bonding system to an electron acceptor moiety. The device can be employed to transfer information from one source of electromagnetic radiation to another.

Abstract: A phosphor composition is disclosed containing a titanium activated hafnium zirconium germanate phosphor which emits electromagnetic radiation principally in the spectral region to which silver halide exhibits native sensitivity. To maximize the intensity of emission the ratio of host metals satisfies the relationship:D.sub.1+x Ge.sub.1-xwhereD is the combined sum of zirconium and halnium andx is 0.25 to -0.70.An X-ray intensifying screen is disclosed containing the phosphor composition.

Abstract: Radiographic elements are disclosed with silver halide emulsion layer units coated on opposite sides of a film support. The radiographic elements are constructed to reduce crossover during exposure by intensifying screens to minimal levels. To permit the minimal crossover radiographic elements to be employed with varied intensifying screens, one of the silver halide emulsion layer units over an exposure range of at least 1.0 log E exhibits an average contrast of from 0.5 to <2.0 and point gammas that differ from the average contrast by less than .+-.40% and the second silver halide emulsion layer unit exhibits a mid-scale contrast of at least 0.5 greater than the average contrast of the first silvert halide emulsion layer unit.

Abstract: An x-ray imaging screen is disclosed comprised of a thermoplastic film support having a planar coating surface and a fluorescent layer coated on that surface. The film support includes an integral lip at its outer boundary extending above the planar coating surface and along peripheral edge portions of the fluorescent layer to protect the fluorescent layer from wear and delamination from the film support. After coating the fluorescent layer on the planar surface of a film support in forming the screen, the coated film support is cut to size by locally heating the film support above its softening point. A softened portion of the film support is caused to flow over the peripheral edge of the fluorescent layer to form the integral lip while cooling the softened portion of the film support immobilizes the integral lip along the peripheral edge of the fluorescent layer, thereby providing a lateral protective buffer for the fluorescent layer along its peripheral edge.

Abstract: The invention relates to an Ag.sub.2 S crystalline membrane, a process for its manufacture, and a process for its use in detecting silver ions or halide ions.The membrane according to the invention comprises silver sulfide doped with an ion capable to form either with Ag.sup.+ or with S.sup.2- a salt much more insoluble than the species in solution. Preferably the membrane further contains an inert hydrophobic compound. The membrane is prepared by coprecipitating silver sulfide with the doping agent, by homogenizing the coprecipitate with the hydrophobic compound and by pressing.The membrane can be used in an electrode to detect silver or halide ions in solution.

Abstract: An intensifying screen for producing a latent image in a silver halide radiographic element upon exposure to an image pattern of X-radiation is disclosed. The intensifying screen contains a fluorescent layer containing a phosphor capable of absorbing X-radiation and emitting longer wavelength electromagnetic radiation comprised of monoclinic crystals of a titanium activated zirconium hafnium oxide phosphor host. The phosphor contains in an amount sufficient to enhance emission of the longer wavelength electromagnetic radiation at least one alkali metal in combination with at least one Group 14 dopant chosen from Periods 3, 4 and 5.

Abstract: A process of forming on a substrate a coating of a precursor of a crystalline rare earth alkaline earth copper oxide or heavy pnictide mixed alkaline earth copper oxide electrical conductor and converting the precursor to the crystalline electrical conductor.

Abstract: An asymmetric radiographic element is disclosed comprised of a transparent film support, silver halide emulsion layer units of differing sensitometric characteristics coated on opposite sides of the film support, and a processing solution decolorizable means for reducing crossover to less than 10 percent. The radiographic element is positioned between intensifying screens and mounted in a cassette for exposure to X-radiation. A feature is included for ascertaining which of the emulsion layer units is positioned nearest a source of X-radiation during exposure.