A method is provided for producing a bonding composition containing copper particles and a second liquid medium. In this production method, the copper particles are produced in a first liquid medium using a wet reduction method, and thus a dispersion of the copper particles is prepared. Subsequently, the first liquid medium in the dispersion is ultimately, finally or eventually replaced with the second liquid medium while the dispersion is kept wet. It is also preferable that the first liquid medium is replaced with another liquid medium one or more times, and the second liquid medium is used in the final replacement. The liquid media are preferably replaced at a temperature of lower than 100 C. The second liquid medium preferably includes one or more of water, alcohol, ketone, ester, ether, and hydrocarbon.

A magnetic bead contains: a magnetic metal powder; and a coating layer with which a particle surface of the magnetic metal powder is coated. When the magnetic bead is left to stand in a state of a dispersion obtained by dispersing the magnetic bead in water, a time until an initial absorbance of the dispersion attenuates to 80% of an absorbance when the standing is started is 90 seconds or longer.

A method of additively manufacturing a structure for use in a reactionary process includes forming a material from metal or metal oxide particles, a dispersion solvent, and a binder. The method also includes depositing the material onto a build platform and curing the material to form a structure for use in a reactionary process. The structure includes the metal or metal oxide particles and is configured to provide a reaction when exposed to a reactant.

The present disclosure belongs to the technical field of magnetic isolation materials, and particularly relates to a magnetic isolation material with counter potential crystals and a preparation method thereof. The magnetic isolation material with counter potential crystals includes a non-magnetoconductive layer, a fusion layer and a magnetic isolation layer. The non-magnetoconductive layer is connected with the magnetic isolation layer through the fusion layer. The non-magnetoconductive layer is made of a graphene-reinforced titanium alloy. The magnetic isolation layer is made of a graphene-reinforced iron-nickel-cobalt alloy. The finally prepared magnetic isolation material with counter potential crystals has a highly magnetoconductive surface and a non-permeable and non-magnetized matrix.

Methods for reducing a concentration of hexavalent chromium within a first aluminum slurry by adding a reducing agent to form a second aluminum slurry are provided. The reducing agent causes a chemical reduction reaction with the hexavalent chromium compound of the first aluminum slurry to form a trivalent chromium compound within the second aluminum slurry such that a first weight ratio of hexavalent chromium to trivalent chromium in the first aluminum slurry is decreased to a second weight ratio of hexavalent chromium to trivalent chromium in the second aluminum slurry, with the second weight ratio being less than the first weight ratio.

Provided is a gold nanoparticle-containing composition excellent in storage stability. A gold nanoparticle-containing composition (100) includes: gold nanoparticles (10); and a zwitterionic compound (20) having a structure represented by any one of the following general formulae (1) to (3), the zwitterionic compound having an HLB value of 12 or less:

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in the general formulae (1) to (3), R.sub.1, R.sub.5, and R.sub.8 each independently represent an organic group, R.sub.2 to R.sub.4, R.sub.6, R.sub.7, and R.sub.9 to R.sub.11 each independently represent a hydrogen atom or an alkyl group, A.sub.1 to A.sub.5 each independently represent a linking group, and Y.sup. represents COO.sup. or SO.sub.3.sup..

The present invention relates to a metal paste for forming a metal wiring containing a solid content of a silver particle and kneaded with a solvent. The solid content of the metal paste contains a silver particle having prescribed particle size distribution and average particle size, and using an amine compound as a protective agent. The solvent is a mixed solvent in which two organic solvents of a solvent A and a solvent B are mixed. The solvent A is dihydroterpineol or terpineol, and the solvent B is at least one organic solvent having a boiling point of 240 C. or more. The mixed solvent has a Hansen solubility parameter distance Ra from dihydroterpineol of 3.0 MPa.sup.1/2 or less. The metal paste further contains a high molecular weight ethyl cellulose as a first additive, and a polyvinyl acetal resin as a second additive.

A copper paste for joining contains metal particles and a dispersion medium, in which the copper paste for joining contains copper particles as the metal particles, and the copper paste for joining contains dihydroterpineol as the dispersion medium. A method for manufacturing a joined body is a method for manufacturing a joined body which includes a first member, a second member, and a joining portion that joins the first member and the second member, the method including: a first step of printing the above-described copper paste for joining to at least one joining surface of the first member and the second member to prepare a laminate having a laminate structure in which the first member, the copper paste for joining, and the second member are laminated in this order; and a second step of sintering the copper paste for joining of the laminate.

A composite electromagnetic wave-absorbing material and preparation method therefor are provided. The composite electromagnetic wave-absorbing material includes following raw materials: magnetite powder, nickel powder, copper powder, samarium oxide, gadolinium oxide, cerium oxide, carbon black powder, graphite powder, epoxy resin, barium titanate powder, antioxidant, curing agent, diluent and leveling agent. Ferrite wave-absorbing materials are used as matrixes to be compounded with nickel powder, copper powder, graphite powder, carbon black and barium titanate, and doped with mixed rare earth oxides through combination of samarium oxide, gadolinium oxide and cerium oxide to thereby obtain the composite electromagnetic wave-absorbing material which combines magnetic loss characteristics of magnetite powder, ferromagnetic behavior of nickel powder and conductivity of copper powder, helping to achieve good electromagnetic wave-absorbing performance. By introducing graphite powder, carbon black powder and barium titanate powder as fillers and doping rare earth, wave-absorbing characteristics of the composite electromagnetic wave-absorbing material are improved.

The invention relates to a sintering paste consisting of: (A) 30 to 40 wt. % of silver flakes with an average particle size ranging from 1 to 20 m, (B) 8 to 20 wt. % of silver particles with an average particle size ranging from 20 to 100 nm, (C) 30 to 45 wt. % of silver(I) oxide particles, (D) 12 to 20 wt. % of at least one organic solvent, (E) 0 to 1 wt. % of at least one polymer binder, and (F) 0 to 0.5 wt. % of at least one additive differing from constituents (A) to (E).