• 한국분말재료학회지
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• 제15권6호
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• pp.466-470
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• 2008

Experiments with a URT-0.5 accelerator (0.5 MeV, 50 ns, 1 kW) generating a nanosecond electron beam for irradiation of silver nitrate in various liquid solutions (water and toluene) were performed with the aim of producing silver nanopowders. A radiochemical reaction allows making weakly agglomerated pure Ag powders with particles of 10-15 nm and 30-50 nm in size by irradiation in toluene and water respectively. The injection of the nanosecond electron beam energy to the solution is optimal. As the absorbed dose increases, the output of the radiochemical reaction does not grow, but more agglomerated powders are synthesized.

• 열처리공학회지
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• 제18권4호
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• pp.242-246
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• 2005

Silver nanoparticles were synthesized by liquid phase reduction method from aqueous silver nitrate solution and borohybride as a reduction agent. The morphology, particle size and shape were influenced by the reaction conditions such as the concentration of $AgNO_3$, a reduction agent and addition of surfactant. The particle size decreased with decreasing the concentration of silver nitrate and using a borohydride. The obtained Ag particles showed the spherical shape with the range of 10-20 nm.

• 한국세라믹학회지
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• 제44권4호
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• pp.208-213
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• 2007

Alumina/silver ($Al_2O_3/Ag$) nanocomposites with Ag content up to 9 vol% were prepared from nanopowder by soaking method using ${\gamma}-Al_2O_3$ of needle type and spark plasma sintering (SPS). The mechanical properties of specimens were investigated three-point flexural strength and toughness as a function of the Ag contents. The maximum flexural strength of the alumina/silver nanocomposite was 850 MPa for the 1 vol% composite, and also higher than monolith alumina as about 800 MPa at 3, 5, and 7 vol% Ag contents. Fracture toughness by single edged V-notch beam (SEVNB) was $4.05MPa{\cdot}m^{1/2}$ for the 3 vol% composite and maintained about $4.00MPa{\cdot}m^{1/2}$ at 5, and 7 vol% Ag content. Microstructure of fracture surface for each fracture specimens was observed. Due to the inhibition effect of alumina grain growth, the average grain size of nanocomposites depends on the content of Ag nano particles. The fracture morphology of nanocomposite with dislocation (sub-grain boundary) by silver nano-particles of second phases in the alumina matrix also showed transgranular fracture-mode compare with intergranular of monolith alumina. Thermal conductivity of specimens at room temperature was about 40 W/mK for the 1 vol% Ag content.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2003년도 춘계학술발표강연 및 논문개요집
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• pp.49-49
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• 2003

Nanometer sized zinc oxide (ZnO) powder was synthesized by a novel "solution-combustion method" and its photocatalytic activity was evaluated with the recovery of Ag from a used photofilm developing solution. Different parameters affecting the reaction rates like wavelength of the W light used, reaction temperature, mass of the used photocatalyst, and effect of scavenger were tested. The optimum parameters were found as follows. UV wavelength of less than 385nm, reaction temperature between 40- 60 $^{\circ}C$, photocatalyst concentration of 3-6 g/1, and scavenger concentration of 0.3-0.4 g/1.