A dielectric composition that contains a first complex oxide represented by (Bi.sub.xNa.sub.1−x)TiO.sub.3—CaTiO.sub.3 and having a perovskite structure as a main component; and at least one second complex oxide having a perovskite structure selected from the group consisting of BaZrO.sub.3, SrZrO.sub.3, CaZrO.sub.3, NaNbO.sub.3, and NaTaO.sub.3 as an auxiliary component. A tolerance factor t when the at least one second complex oxide is BaZrO.sub.3, NaNbO.sub.3, or NaTaO.sub.3 is 0.9016≤t≤0.9035, a tolerance factor t when the at least one second complex oxide is SrZrO.sub.3 is 0.9005≤t≤0.9025, and a tolerance factor t when the at least one second complex oxide is CaZrO.sub.3 is 0.9000 t<0.9020.

The present disclosure includes proppants and methods of making the proppants. The proppants herein may contain titanium dioxide, silicon dioxide, and/or aluminum dioxide. Also included in the present disclosure are methods of using the proppants to treat a reservoir.

A piezoelectric ceramic, which does not contain lead as a constituent element, is characterized in that: its primary component is a perovskite compound expressed by the composition formula (Bi.sub.0.5−x/2Na.sub.0.5−x/2Ba.sub.x)(Ti.sub.1−yMn.sub.y)O.sub.3 (where 0.01≤x≤0.25, 0.001≤y≤0.020); and the coefficient of variation (CV) in grain size among the grains contained therein is 35 percent or lower. The piezoelectric ceramic presents an improved dielectric loss tangent tan δ.

A ferrite sintered magnet comprising an M type Sr ferrite having a hexagonal structure as a main phase, wherein the ferrite sintered magnet comprises La and Co, a content of B is 0.005 to 0.9% by mass in terms of B.sub.2O.sub.3, a content of Zn is 0.01 to 1.2% by mass in terms of ZnO, and the ferrite sintered magnet satisfies [La]/[Zn]≤0.79 and [Co]/[Zn]≤0.67 when an atomic concentration of La is represented by [La], an atomic concentration of Co is represented by [Co], and an atomic concentration of Zn is represented by [Zn].

The invention relates to a ceramic material, comprising lead zirconate titanate, which additionally contains K and optionally Cu. The ceramic material can be used in an electroceramic component, for example a piezoelectric actuator. The invention also relates to methods for producing the ceramic material and the electronic component.

A molding material mixture for producing casting molds for metal processing, particularly for non-ferrous metals, such as aluminum or magnesium, is intended to reduce problems such as metal-mold reaction and/or shrinkage porosity defect. The free-flowing refractory molding material in the molding material mixture is coated with a mixture of inorganic salts exhibiting a eutectic melting point in the range of about 400 C to about 500 C, particularly in the range of about 420 C to about 460 C. Preferably this coating occurs by contacting the inorganic salt mixture with the molding material mixture at a temperature between 500 C and 700 C, in a manner that maintains the free-flowing nature of the coated product. One mixture of inorganic salts that is used is a mixture consisting of, by weight: 74% potassium fluoroborate; 15% potassium chloride; and 12% potassium fluoride. This mixture has a eutectic melting point of 420 C.

The present disclosure relates to a porous ceramic media that may include a chemical composition, a phase composition, a total open porosity content of at least about 10 vol. % and not greater than about 70 vol. % as a percentage of the total volume of the ceramic media, and a nitric acid resistance parameter of not greater than about 500 ppm. The chemical composition for the porous ceramic media may include SiO.sub.2, Al.sub.2O.sub.3, an alkali component and a secondary metal oxide component selected from the group consisting of an Fe oxide, a Ti oxide, a Ca oxide, a Mg oxide and combinations thereof. The phase composition may include an amorphous silicate, quartz and mullite.

A process for the manufacture of inorganic fibres comprises: (a) selecting a composition and proportion of: (i) silica sand; (ii) lime comprising at least 0.10 wt % magnesia; and (iii) optional additives comprising a source of oxides or non-oxides of one or more of the lanthanides series of elements, or combinations thereof; (b) mixing the silica sand; lime; and optional additives to form a mixture; (c) melting the mixture in a furnace; and (d) shaping the molten mixture into inorganic fibres. The raw materials selection comprises composition selection and proportion selection of the raw materials to obtain an inorganic fibre composition comprising a range of from 61.0 wt % and 70.8 wt % silica; less than 2.0 wt % magnesia; less than 2.0% incidental impurities; and no more than 2.0 wt % of metal oxides and/or metal non-oxides derived from said optional additives; with calcia providing the balance up to 100 wt %; and wherein the inorganic fibre composition comprises no more than 0.80 wt % Al.sub.2O.sub.3 derived from the incidental impurities and/or the optional additives.

The novel process enables designing of raw materials and processing parameters, enabling synergistic and simultaneous chemical reactions among the various reactants of the design mix of chemical precursor of brine sludge which includes barium sulphate, magnesium hydroxide, calcium carbonate, sodium chloride, silica, aluminum containing compounds necessary for developing highly efficient shielding phases leading to homogenous matrix of shielding materials.

A solid electrolyte, in which a part of an element contained in a mobile ion-containing material is substituted, and an occupied impurity level that is occupied by electrons or an unoccupied impurity level that is not occupied by electrons is provided between a valence electron band and a conduction band of the mobile ion-containing material, and a smaller energy difference out of an energy difference between a highest level of energy in the occupied impurity level and an energy and a LUMO level difference between a lowest level of energy in the unoccupied impurity level and a HOMO level is greater than 0.3 eV.