A method of testing the composition or quality of water includes dissolving about two parts by weight of a 2-hydroxybenzyl alcohol and about one part by weight of a sodium nitroprusside in about seventy-five parts by weight of a polyethylene glycol; adding the sodium nitroprusside solution to a water sample to catalyze an indophenol monochloramine reaction; and detecting the concentration of monochloramine in the water sample. The polyethylene glycol may be a polyethylene glycol 300, a PEG-400 or a PEG-1000. The method may also be accomplished with a solution made by dissolving a 2-hydroxybenzyl alcohol and a sodium nitroprusside in a mixture of propane-1,2-diol and water.

A method for synthesising a molecular magnetic material from a paramagnetic reactant including a d-electron metal in a paramagnetic form, a diamagnetic reactant comprising a d-electron metal in a diamagnetic form, and at least one donor of cyanide (CN—) ligands being a separate compound and/or contained in the paramagnetic reactant and/or in the diamagnetic reactant.

A method for synthesising a molecular magnetic material from a paramagnetic reactant including a d-electron metal in a paramagnetic form, a diamagnetic reactant comprising a d-electron metal in a diamagnetic form, and at least one donor of cyanide (CN—) ligands being a separate compound and/or contained in the paramagnetic reactant and/or in the diamagnetic reactant.

A prussian blue analog having a core-shell structure, which has a core and a cladding layer that dads the core, wherein

the chemical formula of the core is the following Formula 1,

Na.sub.xP[R(CN).sub.6].sub.δ.zH.sub.2O and the chemical formula of the cladding layer is the following Formula 2, A.sub.yL[M(CN).sub.6].sub.α.wH.sub.2O is described. The prussian blue analog has good storage stability, and thus can greatly reduce the manufacturing cost at the subsequent battery cell level. A method for preparing the prussian blue analog having a core-shell structure, as well as a sodium-ion secondary battery, a battery module, a battery pack and a powered device comprising the same are described.

A prussian blue analog having a core-shell structure, which has a core and a cladding layer that dads the core, wherein

the chemical formula of the core is the following Formula 1,

Na.sub.xP[R(CN).sub.6].sub.δ.zH.sub.2O and the chemical formula of the cladding layer is the following Formula 2, A.sub.yL[M(CN).sub.6].sub.α.wH.sub.2O is described. The prussian blue analog has good storage stability, and thus can greatly reduce the manufacturing cost at the subsequent battery cell level. A method for preparing the prussian blue analog having a core-shell structure, as well as a sodium-ion secondary battery, a battery module, a battery pack and a powered device comprising the same are described.

The present invention is to provide a novel adsorbent which is low in cost, has versatility and high adsorption ability. Specifically, the present invention is to provide an adsorbent of a specific metal element containing a metal salt of a cyanometallic acid, a method for producing the same, and a method for removing the ion of the element that is the target of adsorption using such an adsorbent.

The present invention is to provide a novel adsorbent which is low in cost, has versatility and high adsorption ability. Specifically, the present invention is to provide an adsorbent of a specific metal element containing a metal salt of a cyanometallic acid, a method for producing the same, and a method for removing the ion of the element that is the target of adsorption using such an adsorbent.

The present invention is to provide a novel adsorbent which is low in cost, has versatility and has high adsorption ability. Specifically, the present invention is to provide an adsorbent containing a metal salt of a cyanometallic acid obtained by a reaction of a salt of a cyanometallic acid and a compound containing a metal element, wherein the reaction is carried out using the compound containing a metal element in an amount of less than 100 mol % of the theoretical amount relative to 1 mol of the salt of a cyanometallic acid, a method of producing the same, and a method for removing harmful ions from water using such an adsorbent.

The present invention is to provide a novel adsorbent which is low in cost, has versatility and has high adsorption ability. Specifically, the present invention is to provide an adsorbent containing a metal salt of a cyanometallic acid obtained by a reaction of a salt of a cyanometallic acid and a compound containing a metal element, wherein the reaction is carried out using the compound containing a metal element in an amount of less than 100 mol % of the theoretical amount relative to 1 mol of the salt of a cyanometallic acid, a method of producing the same, and a method for removing harmful ions from water using such an adsorbent.

Solid nanocomposite material comprising nanoparticles of a hexacyanometallate or octacyanometallate of an alkali metal and of a transition metal, of formula [Alk.sup.+.sub.x]M.sup.n+[M′(CN).sub.m].sup.z− in which Alk is an alkali metal, x is 1 or 2, M is a transition metal, n is 2 or 3, M′ is a transition metal, m is 6 or 8, z is 3 or 4, attached to at least one surface of a porous inorganic solid support, in which the nanoparticles are attached by adsorption to the at least one surface of the solid support, and in which the surface is a basic surface. Method for preparing this material. Method for extracting at least one metal cation from a liquid medium containing it, wherein the liquid medium is brought into contact with the material.