An electrode, a preparation method therefor, and uses thereof. Titanium or titanium alloy is used as a base material of the electrode, the outer surface of the base material is coated with a composite material coating, and the composite material coating is prepared by coating a composite material solution and carrying out drying and sintering. The composite material solution is a nanoscale solution formed by dissolving transition metal elements in ethanol. The nanoscale solution is an ethanol solution of the nanoscale transition metal with particles of the transition metal as solutes thereof. The transition metal elements are platinum, iridium, ruthenium, gold, cerium, rhodium, tantalum, manganese, nickel, palladium, yttrium, gadolinium, cobalt, europium, lanthanum, neodymium, zirconium and titanium, and the molar ratio of the transition metal elements platinum, iridium, ruthenium, gold, cerium, rhodium, tantalum, manganese, nickel, palladium, yttrium, gadolinium, cobalt, europium, lanthanum, neodymium, zirconium and titanium in the composite material solution is 5-15:23-34:14-21:1-7:9-17:3-12:15-27:3-6:2-9:10-23:15-27:2-8:15-30:3-12:4-14:1-10:6-15:20-50.

An electrode, a preparation method therefor, and uses thereof. Titanium or titanium alloy is used as a base material of the electrode, the outer surface of the base material is coated with a composite material coating, and the composite material coating is prepared by coating a composite material solution and carrying out drying and sintering. The composite material solution is a nanoscale solution formed by dissolving transition metal elements in ethanol. The nanoscale solution is an ethanol solution of the nanoscale transition metal with particles of the transition metal as solutes thereof. The transition metal elements are platinum, iridium, ruthenium, gold, cerium, rhodium, tantalum, manganese, nickel, palladium, yttrium, gadolinium, cobalt, europium, lanthanum, neodymium, zirconium and titanium, and the molar ratio of the transition metal elements platinum, iridium, ruthenium, gold, cerium, rhodium, tantalum, manganese, nickel, palladium, yttrium, gadolinium, cobalt, europium, lanthanum, neodymium, zirconium and titanium in the composite material solution is 5-15:23-34:14-21:1-7:9-17:3-12:15-27:3-6:2-9:10-23:15-27:2-8:15-30:3-12:4-14:1-10:6-15:20-50.

The present invention provides a solder alloy, a solder paste, a solder ball, a resin flux-cored solder and a solder joint, both of which has the low-melting point to suppress the occurrence of the fusion failure, improves the ductility and the shear strength, and has excellent heat-cycle resistance. The solder alloy comprises an alloy composition composed of 35 to 68 mass % of Bi, 0.1 to 2.0 mass % of Sb, 0.01 to 0.10 mass % of Ni, and a balance of Sn. The alloy composition may contain at least one of Co, Ti, Al and Mn in total amount of 0.1 mass % or less. The solder alloy may be suitably used for a solder paste, a solder ball, a resin flux-cored solder and a solder joint.

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 PtB.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 PtB.sub.2 nanoparticle has a negative charge.

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 PtB.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 PtB.sub.2 nanoparticle has a negative charge.

A chemical reaction heat source for use in heaters used in down-hole application. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperature down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.

A chemical reaction heat source for use in heaters used in down-hole application. The heat source has a fuel composition that comprises thermite and a damping agent. The use of the thermite mix enables the heaters of the present invention to generate hotter temperature down wells. This in turn allows the use of Bismuth/Germanium alloys, which have higher melting points, to enable the production of plugs for the abandonment of deeper wells where subterranean temperatures are higher.

The present invention addresses the problem of providing a novel, sold metal alloy. Provided is a metal alloy containing two or more types of metal, wherein an equilibrium diagram of the metal alloy shows the two or more types of metal in a finely mixed state at the nanolevel in a specific region where the two types of metal are unevenly distributed. This metal alloy has a substitutional solid solution of the two or more types of metal as the principal constituent thereof. This metal alloy is preferably one obtained by precipitation after mixing ions of two or more types of metal and a reducing agent in a thin-film fluid formed between processing surfaces, at least one of which rotates relative to the other, which are arranged so as to face one another and are capable of approaching and separating from one another.

The present invention addresses the problem of providing a novel, sold metal alloy. Provided is a metal alloy containing two or more types of metal, wherein an equilibrium diagram of the metal alloy shows the two or more types of metal in a finely mixed state at the nanolevel in a specific region where the two types of metal are unevenly distributed. This metal alloy has a substitutional solid solution of the two or more types of metal as the principal constituent thereof. This metal alloy is preferably one obtained by precipitation after mixing ions of two or more types of metal and a reducing agent in a thin-film fluid formed between processing surfaces, at least one of which rotates relative to the other, which are arranged so as to face one another and are capable of approaching and separating from one another.

A biodegradable Zn—Mg—Bi zinc alloy and a preparation method thereof. The method including: melting magnesium under an inert atmosphere to obtain a magnesium melt; adding bismuth particles to the magnesium melt followed by reaction under stirring and heat preservation treatment to obtain a Mg—Bi alloy melt; allowing the Mg—Bi alloy melt to stand in a furnace; subjecting the Mg—Bi alloy melt to refining, slagging-off, casting and demoulding to obtain Mg-50 wt. % Bi alloy ingot; melting zinc to obtain a zinc melt; adding the Mg-50 wt. % Bi alloy ingot and pure magnesium or pure bismuth followed by heating to a preset temperature, stirring and heat preservation to obtain a Zn—Mg—Bi alloy melt; allowing the Zn—Mg—Bi alloy melt to stand in a furnace followed by refining, slagging-off, casting and demoulding to obtain the biodegradable Zn—Mg—Bi zinc alloy.