The present invention refers to the method for synthesis an absorbent material consisting of a phase of tetravalent manganese feroxyhyte (δ-Fe.sub.(1-x)Mn.sub.xOOH) with a negatively charged grain surface in which a percentage of iron has been isomorphically substituted by manganese atoms at 0.05-25%. Its' production is carried out in two continuous flow stirred-tank reactors arranged in serial configuration, where mild acidic conditions (pH 5-6) prevail in the first reactor and mild alkaline conditions (pH 9-10) together with high redox potential (600-700 mV) in the second reactor. The material can be used to uptake mercury, as well as other heavy metals from both water and hot gas streams. Specifically, the adsorption capacity is determined by the magnitude of the negative surface charge and the isoelectric point that can be both adjusted by the synthesis process parameters.

A composite oxide black pigment has characteristics to absorb visible rays and near infrared rays, and is composed of an oxide of main constituent metals including copper, manganese and iron. In a wavelength region of 400 to 1,000 nm, the composite oxide black pigment has a minimum wavelength, at which a transmittance becomes minimum, in a wavelength region of 600 to 800 nm, a molar ratio of manganese/iron is 3/1 to 30/1, and a molar ratio of copper/(manganese+iron) is 1/2 to 1.2/2. Its sole use makes it possible to obtain a transparent vivid bluish, neutral gray color, and also to maximize an absorption in a near infrared region. It is, therefore, excellent in near infrared absorption characteristics.

The present application discloses a positive electrode active material satisfying the chemical formula L.sub.xNa.sub.yM.sub.zCu.sub.αFe.sub.βMn.sub.γO.sub.2+δ−0.5ηX.sub.η and a preparation method therefor, a sodium ion battery and an apparatus including such battery, wherein L is a doping element at alkali metal site, M is a doping element at transition metal site, and X is a doping element at oxygen site, 0≤x<0.35, 0.65≤y≤1, 0<α≤0.3, 0<β≤0.5, 0<γ≤0.5, −0.03≤δ≤0.03, 0≤η≤0.1, z+α+β+γ=1, mx+y+nz+2α+3β+4γ=2(2+δ), m is the valence state of L, and n is the valence state of M; and the pH of the positive electrode active material is 10.5-13, wherein L is a doping element at alkali metal site, M is a doping element at transition metal site, and X is a doping element at oxygen site.

The invention relates to sulfonated aminomethylated chelate resins, to a method for producing same, to the use thereof for obtaining and purifying metals, in particular rare earth metals, from aqueous solutions and organic liquids, and for producing highly pure silicon.

The object of the present invention relates to ferrite particles for bonded magnets and a resin composition for bonded magnets which is capable of obtaining a bonded magnet molded product having a good magnetic force and a magnetic waveform as well as high iHc and Hk by injection molding. The present invention aims at providing a bonded magnet molded product using the ferrite particles and the resin composition. The aforementioned object of the present invention can be achieved by ferrite particles for bonded magnets which have a crystal distortion of not more than 0.14 as measured by XRD, and an average particle diameter of not less than 1.30 μm as measured by Fisher method; a resin composition for bonded magnets; and a molded product obtained by injection-molding the resin composition.

A method for producing metal carbonate is disclosed. The method includes the following steps of providing a first mixture of metal and a catalyst containing iron, NO groups, and N-containing ligands first; then introducing carbon dioxide to the first mixture to form a second mixture and obtaining a product. The method described here can improve the yield and decrease the cost of metal carbonate production.

A method for producing metal carbonate is disclosed. The method includes the following steps of providing a first mixture of metal and a catalyst containing iron, NO groups, and N-containing ligands first; then introducing carbon dioxide to the first mixture to form a second mixture and obtaining a product. The method described here can improve the yield and decrease the cost of metal carbonate production.

There is provided a ferrite sintered magnet having a high residual magnetic flux density. A ferrite sintered magnet 2 includes a plurality of main phase particles 5 including ferrite having a hexagonal structure, the number of core-shell structured particles 5A having a core 7 and a shell 9 covering the core 7, among the main phase particles 5, is smaller than the number of the main phase particles 5 other than the core-shell structured particles 5A.

A polycrystalline bulk body of this invention has uniformity in superconducting properties, in comparison to a polycrystalline bulk body including crystal grains each constituted by (Ba.sub.1-xK.sub.x)Fe.sub.2As.sub.2. A polycrystalline bulk body (1) of this invention includes crystal grains each constituted by an iron-based compound (10) expressed by chemical formula AA′Fe.sub.4As.sub.4, where A is Ca and A′ is K, the iron-based compound (10) having a crystal structure in which AFe.sub.2As.sub.2 layers (16) and A′Fe.sub.2As.sub.2 layers (17) are alternately stacked.

A polycrystalline bulk body of this invention has uniformity in superconducting properties, in comparison to a polycrystalline bulk body including crystal grains each constituted by (Ba.sub.1-xK.sub.x)Fe.sub.2As.sub.2. A polycrystalline bulk body (1) of this invention includes crystal grains each constituted by an iron-based compound (10) expressed by chemical formula AA′Fe.sub.4As.sub.4, where A is Ca and A′ is K, the iron-based compound (10) having a crystal structure in which AFe.sub.2As.sub.2 layers (16) and A′Fe.sub.2As.sub.2 layers (17) are alternately stacked.