The piezoelectric composition is represented by the following Chemical Formula (1):
x[Bi.sub.mFeO.sub.3]-y[Ba.sub.mTiO.sub.3]-z[Sr.sub.mTiO.sub.3](1)
wherein 0.5x0.8, 0.02y0.4, 0.02z0.2, x+y+z=1, and 0.96m1.04.

A process of forming a coated cathode active material include preparing a cathode material precursor by co-precipitation; coating the cathode material precursor with an electrochemically inert coating material precursor by precipitation to form a coated cathode material precursor; lithiating the coated cathode material precursor with a lithium source material to form a lithiated coated cathode material precursor; and sintering the lithiated coated cathode material precursor to form a cathode active material coated with an electrochemically inert material.

A powder for dust cores includes an aggregate of soft magnetic particles, each of which includes a soft magnetic metal particle, and a ferrite film that covers a surface of the soft magnetic metal particle and includes ferrite crystal grains having a spinel structure. A diffraction peak derived from the ferrite crystal grains exists in a powder X-ray diffraction pattern. By a method for producing a powder for dust cores, a raw material powder that includes an aggregate of soft magnetic metal particles is prepared. Furthermore, many ferrite fine particles are formed on a surface of each of the soft magnetic metal particles of the raw material powder. Additionally, the ferrite fine particles are coarsely crystallized through heat treatment to form a ferrite film, which includes ferrite crystal grains having a spinel structure, on the surface of the each of the soft magnetic metal particles.

Some variations provide a method of making water-dispersed hexaferrite nanoparticles, comprising: providing a first salt containing iron, a second salt containing barium and/or strontium, and a third salt containing an anion or cation that is capable of forming a ligand with the hexaferrite nanoparticles; combining the first salt, second salt, third salt, and water to form a reaction mixture; subjecting the reaction mixture to effective reaction conditions to produce hexaferrite nanoparticles with the anion or cation in the third salt forming a ligand on the surface, so that the hexaferrite nanoparticles are dissolved and/or suspended in the reaction mixture; and obtaining water-dispersed hexaferrite nanoparticles with an average zeta potential of at least 20 mV. The water-dispersed hexaferrite nanoparticles have a hexaferrite content of at least 85 wt %. The method may further include assembling water-dispersed hexaferrite nanoparticles into a magnetic component, such as a self-biased hexaferrite film on a semiconductor substrate.

Methods to fabricate tightly packed arrays of nanoparticles are disclosed, without relying on organic ligands or a substrate. In some variations, a method of assembling particles into an array comprises dispersing particles in a liquid solution; introducing a triggerable pH-control substance capable of generating an acid or a base; and triggering the pH-control substance to generate an acid or a base within the liquid solution, thereby titrating the pH. During pH titration, the particle-surface charge magnitude is reduced, causing the particles to assemble into a particle array. Other variations provide a device for assembling particles into particle arrays, comprising a droplet-generating microfluidic region; a first-fluid inlet port; a second-fluid inlet port; a reaction microfluidic region, disposed in fluid communication with the droplet-generating microfluidic region; and a trigger source configured to trigger generation of an acid or a base from at least one pH-control substance contained within the reaction microfluidic region.

A highly active trimetallic mixed transition metal oxide material has been developed. The material may be sulfided to generate metal sulfides which are used as a catalyst in a conversion process such as hydroprocessing. The hydroprocessing may include hydrodenitrification, hydrodesulfurization, hydrodemetallation, hydrodesilication, hydrodearomatization, hydroisomerization, hydrotreating, hydrofining, and hydrocracking.

To provide magnetoplumbite-type hexagonal ferrite particles represented by Formula (1) and having a single crystal phase, and the application. In Formula (1), A represents at least one metal element selected from the group consisting of Sr, Ba, Ca, and Pb, and x satisfies 1.5x8.0.

AFe.sub.(12-x)Al.sub.xO.sub.19Formula (1)

Provided is a material that can be used as a potassium secondary battery positive electrode active material (particularly a potassium ion secondary battery positive electrode active material), other than Prussian blue, by using a potassium compound and a potassium ion secondary battery positive electrode active material comprising the potassium compound, the potassium compound being represented by general formula (1):
K.sub.nA.sub.kBO.sub.m,
wherein A is a positive divalent element in groups 7 to 11 of the periodic table; B is positive tetravalent silicon, germanium, titanium or manganese, excluding a case in which A is manganese and B is titanium, and a case in which A is cobalt and B is silicon; n is 1.5 to 2.5; and m is 3.5 to 4.5.

Provided is a battery comprising a cathode, an anode, and an electrolyte layer. The electrolyte layer includes a first electrolyte layer and a second electrolyte layer. The first electrolyte layer includes a first solid electrolyte material. The second electrolyte layer includes a second solid electrolyte material which is a material different from the first solid electrolyte material. The first solid electrolyte material includes lithium, at least one kind selected from the group consisting of metalloid elements and metal elements other than lithium, and at least one kind selected from the group consisting of chlorine, bromine, and iodine. The first solid electrolyte material does not include sulfur.

A ferrous modified selenium sol for inhibiting accumulation of cadmium and arsenic in rice and the preparation method and application thereof are disclosed. The method includes: dissolving an iron-containing compound and a selenium-containing compound into water; adding a reductant to the solution, and stirring until no more precipitation is generated, then adding carbonate, continuing to stir until no more precipitation is generated, and then filtering, taking the precipitation, and washing to obtain the precipitation of the selenium element and ferrous carbonate; adding an emulsifier to a citric acid buffer solution to obtain an emulsified citric acid buffer solution; adding the precipitation of the selenium element and ferrous carbonate to the emulsified citric acid buffer solution to obtain a sol system; and evaporating to concentrate the sol system, and adjusting the pH to 4.5-8.5 to obtain a ferrous modified selenium sol for inhibiting the accumulation of cadmium and arsenic in rice.