Provided is nickel powder obtained by adding seed crystals to a nickel ammine complex solution and performing hydrogen reduction reaction under high temperatures and high pressures, wherein the nickel powder does not produce dust during handling, and a container can be efficiently filled with the nickel powder. The method for producing nickel powder includes: adding seed crystals and a surfactant having a nonionic or anionic functional group to a solution containing a nickel ammine complex to forma mixed slurry; and subjecting the mixed slurry to hydrogen reduction under high temperature and high pressure conditions in a pressure vessel to obtain nickel powder from the mixed slurry.

A nanoparticle production apparatus and automatic production apparatus that allow continuous mass production of nanoparticles with a uniform particle diameter and allow freely adjusting the generation time are provided. This nanoparticle production apparatus is characterized by being configured from: reaction tubes (30, 40) which are filled with the same solvent (11) as that in a ingredient liquid (18), which is used in nanoparticle production and comprises an ingredient material (12) mixed into the solvent (11); a heating apparatus (22) which controls the temperature of the solvent (11) in the reaction tubes (30, 40) to the synthesis temperature of the nanoparticles (26); inflow ends (30e, 40e) of the reaction tubes into which the ingredient liquid (18) is supplied; rotors (35, 45) which form spiral flows (e, j) along the inner surface of the outer walls (30h, 40h) of the reaction tubes while mixing the ingredient liquid (18) supplied and the solvent (11) present in the reaction tubes (30, 40); and outflow ends (30f, 40f) of the reaction tubes (30, 40) for forming, in the spiral flows (e, j), nanoparticles (26) from the ingredient material (12) and discharging a generation liquid (65) containing the nanoparticles (26).

Provided are a fine silver particle dispersion which exhibits low temperature sinterability and in which fine silver particles are uniformly dispersed in a variety of solvents (and especially highly polar solvents); fine silver particles that exhibit low temperature sinterability and excellent dispersion stability in a variety of solvents (and especially highly polar solvents); a dispersion obtained using the fine silver particles; and a method for producing same. The fine silver particle dispersion is characterized by containing fine silver particles, a short chain amine having 5 or fewer carbon atoms, and a highly polar solvent and in that the partition coefficient (log P) of the short chain amine is 1.0 to 1.4.

Provided are processes for preparing a thermodynamically stable PtBi.sub.2 alloy nanoparticle. In certain aspects, the process comprises preparing an aqueous mixture, with the aqueous mixture comprising: an inorganic compound comprising SnCl.sub.2; an inorganic compound comprising Bi; and HCl. The process further comprises adding PtCl.sub.4 to the mixture. The process results in the spontaneous reduction of Bi and Pt. Excess SnCl.sub.2 is adsorbed as a ligand at the surface of the PtBi.sub.2 alloy nanoparticle, which serves to stabilize the nanoparticle. Another aspect provides a thermodynamically stable PtBi.sub.2 nanoparticle. The nanoparticle comprises a core comprising a PtBi.sub.2 alloy. The nanoparticle further comprises a shell at least partially encapsulating the core, with the shell comprising stannous chloride. The thermodynamically stable PtBi.sub.2 nanoparticle has a negative charge.

A method of forming monodispersed metal nanowires comprising; forming a reaction mixture including a metal salt, a capping agent and an ionic additive in a polar solvent at a first temperature; and forming metal nanowires by reducing the metal salt in the reaction mixture.

Methods for forming nanostructures of various shapes are disclosed. Nanocubes, nanowires, nanopyramids and multiply twinned particles of silver may by formed by combining a solution of silver nitrate in ethylene glycol with a solution of poly(vinyl pyrrolidone) in ethylene glycol. Hollow nanostructures may be formed by reacting a solution of solid nanostructures comprising one of a first metal and a first metal alloy with a metal salt that can be reduced by the first metal or first metal alloy. Nanostructures comprising a core with at least one nanoshell may be formed by plating a nanostructure and reacting the plating with a metal salt.

Process for producing a layer structure, which comprises the steps: E1. provision of a composition comprising i. gold (Au) particles in an amount in the range from 0.1 to 50% by weight; ii. a balance to 100% by weight of a polar, protic organic solvent; iii. less than 5% by weight of water, where the % by weight, in each case based on the total mass of the composition, add up to 100% by weight; E2. application of the composition to a substrate to give a precursor; E3. heating of the precursor to a temperature in the range from 25 to 200 C. to give the layer structure.

Described herein is a method of making a reduced metal nanoparticle, the method including mixing a reactive reducing agent with a metal salt in a solution at a temperature of 4-100? C., and forming the reduced metal nanoparticles in the solution. Also described is a kit including a reactive reducing agent that is sensitive to ?galactosidase, a metal salt, and optionally a modifying agent/functionalizing agent for reduced metal nanoparticles. A 3,4-cyclohexeneoesculetin-B-D-galacto pyranoside (SGNP) gold nanoparticle and its use for measuring ?galactosidase enzyme activity, comprising by detecting a structural change in the SGNPs caused by the ?galactosidase are described. Further described are a point of care device, a chip, a biosensor, a laboratory animal, a gene delivery agent, a drug delivery agent, a diagnostic agent, or a disease targeting agent including SGNPs.

A silver powder, wherein the silver powder satisfies D.sub.50-IPA>D.sub.50-W, where in measurement of a volume-based particle size distribution of the silver powder by a laser diffraction particle size distribution analysis, D.sub.50-IPA (m) is a cumulative 50% point of particle diameter of the silver powder when isopropyl alcohol (IPA) is used as a measurement solvent for dispersing the silver powder, and D.sub.50-W (m) is a cumulative 50% point of particle diameter of the silver powder when water is used as a measurement solvent for dispersing the silver powder, and wherein a phosphorus content in the silver powder is 0.01% by mass or more but 0.3% by mass or less.

A method for manufacturing a ferromagnetic-particle includes preparing a manufacturing apparatus including an induction heating coil; a radiofrequency power source electrically connected to the induction heating coil and configured to form an alternating field inside the induction heating coil; a pipe disposed to pass through the induction heating coil, in which at least a partial area of the pipe in an axial direction thereof is formed of a dielectric material and an area, which is nearer to one end of the pipe than the area formed of a dielectric material, is formed of a conductive material; and a pump configured to introduce, from the one end of the pipe, an alkaline reaction liquid in which metal ions of a ferromagnetic metal and hydroxide ions are dissolved; reacting the reaction liquid in the pipe, introduced by the pump, by forming an alternating field inside the induction heating coil; and generating the ferromagnetic-particle in the pipe based on the reaction of the reaction liquid in the pipe.