A compound M.sub.jX.sub.p which is particularly suitable for use in a battery prepared by the complexometric precursor formulation methodology wherein: M.sub.j is at least one positive ion selected from the group consisting of alkali metals, alkaline earth metals and transition metals and j is an integer representing the moles of said positive ion per moles of said M.sub.jX.sub.p; and X.sub.p, a negative anion or polyanion from Groups IIIA, IVA, VA, VIA and VIIA and may be one or more anion or polyanion and p is an integer representing the moles of said negative ion per moles of said M.sub.jX.sub.p.

Crystalline NH.sub.4Be.sub.2BO.sub.3F.sub.2 or Be.sub.2BO.sub.3F (abbreviated as BBF) has nonlinear optical effect, is not deliquescent in the air, is chemically stable. They can be used in a variety of nonlinear optical fields and will pioneer the nonlinear optical applications in the deep UV band.

Disclosed are a borate MWDC with a low dielectric constant and a preparation method thereof by cold sintering. The method for preparing a borate MWDC with a low dielectric constant by cold sintering, including: subjecting a boron source and a metal source to first mixing to obtain a first mixture; subjecting the first mixture to presintering to obtain a presintered material; subjecting the presintered material and a boron oxide solution to second mixing to obtain a second mixture; and subjecting the second mixture to cold sintering to obtain the borate MWDC with the low dielectric constant.

The invention relates to cation borate present in powder form, with a small grain size and low water solubility. The cation borate present in powder form and a suspension produced therefrom are suitable for example for the treatment of coating materials (such as wood preservatives), in particular fungicidal, biocidal and insecticidal treatment.

The present invention relates to a barium tetraborate compound and a barium tetraborate non-linear optical crystal, and a preparation method and use thereof, wherein the chemical formulae of the barium tetraborate compound and the non-linear optical crystal thereof are both BaB.sub.4O.sub.7, with a molecular weight of 292.58; the barium tetraborate non-linear optical crystal has a non-centrosymmetric structure, which belongs to a hexagonal system, and has a space group P6.sub.5 and lattice parameters of a=6.7233(6) , c=18.776(4) , V=735.01(17) .sup.3, and Z=6, wherein the powder frequency-doubled effect thereof is two times that of KDP (KH.sub.2PO.sub.4), and the ultraviolet cut-off edge is lower than 170 nm. The barium tetraborate compound is synthesized by a solid-phase reaction method; the barium tetraborate non-linear optical crystal is grown by a high-temperature molten solution method; and the crystal has a moderate mechanical hardness, is easy to cut, polish and store, and is widely applicable in the non-linear optics of a double-frequency doubling generator, an upper frequency converter, a lower frequency converter or an optical parameter oscillator etc.

Provided area deep ultraviolet non-linear optical crystal of barium borate hydrate, a preparation method therefor and the use thereof. The chemical formula of the crystal is Ba.sub.2B.sub.11O.sub.22H.sub.7, belonging to monoclinic system, with the space group thereof being P2.sub.1, the crystal cell parameters thereof being a=6.7719(10) , b=21.1195(4) , c=6.8274(10) , =119.3950(10) , and the molecular weight thereof being 752.65. The non-linear optical crystal of borate is obtained by means of programmed cooling or natural cooling using a hydrothermal method. The crystal powder has a frequency-doubled effect of about 2 times that of KDP (KH.sub.2PO.sub.4) and an ultraviolet cut-off edge of below 175 nm and can be used as a deep ultraviolet non-linear optical crystal. The growth process of the crystal has advantages such as simple, a low cost, a low toxicity, a short growth cycle, stable physical and chemical properties, etc. The deep ultraviolet non-linear optical crystal of barium borate hydrate Ba.sub.2B.sub.11O.sub.22H.sub.7 is widely used in the preparation of non-linear optical devices such as frequency doubling generators, upper frequency converters, lower frequency converters, optical parametric oscillators etc.

A particulate nanocomposite material comprising, as determined by X-ray diffraction (XRD): elemental carbon (C); elemental nickel (Ni) in a cubic crystalline phase; a cubic nickel oxide (NiO) crystalline phase; an orthorhombic calcium borate (CaB.sub.2O.sub.4) crystalline phase; and, a magnesium borate (MgB.sub.2O.sub.4) crystalline phase. The particulate nanocomposite material is characterized in that, based on the total number of atoms in the nanocomposite material: the atomic concentration of carbon is from about 1 atomic percent (at. %) to about 10 at. %; the atomic concentration of nickel is from about 1 at. % to about 10 at. %; the atomic concentration of boron (B) is from about 1 at. % to about 10 at. %; the atomic concentration of magnesium (Mg) is from about 5 at. % to about 15 at. %; and, the atomic concentration of calcium (Ca) is from about 1 at. % to about 10 at. %.

A porous particulate nanocomposite material includes, as determined by X-ray diffraction, an orthorhombic CaB.sub.2O.sub.4 crystalline phase; an orthorhombic Co.sub.3(BO.sub.3).sub.2 crystalline phase; an orthorhombic PbO.sub.2 crystalline phase; and, a cubic Co.sub.3O.sub.4 crystalline phase. The porous particulate nanocomposite material is in the form of particles having a matrix phase with a smooth surface and in which sharp-edged plates are embedded and protrude.

A particulate nanocomposite material comprising, as determined by X-ray diffraction (XRD): elemental carbon (C); elemental nickel (Ni) in a cubic crystalline phase; a cubic nickel oxide (NiO) crystalline phase; an orthorhombic calcium borate (CaB.sub.2O.sub.4) crystalline phase; and, a magnesium borate (MgB.sub.2O.sub.4) crystalline phase. The porous particulate nanocomposite is characterized in that, based on the total number of atoms in the particulate nanocomposite material: the atomic concentration of carbon is from about 1 atomic percent (at. %) to about 10 at. %; the atomic concentration of nickel is from about 1 at. % to about 10 at. %; the atomic concentration of boron (B) is from about 1 at. % to about 10 at. %; the atomic concentration of magnesium (Mg) is from about 5 at. % to about 15 at. %; and, the atomic concentration of calcium (Ca) is from about 1 at. % to about 10 at. %.