Ni coated composite was successfully Prepared by the electroless deposition Process. The average size of Ni particles coated on the matrix powder was about 20 nm. It was hard to find any reaction compound as an impurity at interface between and Ni particles after sintering. The characterization of microstructure crystal structure and fracture behavior of the sintered body were investigated using XRD, TEM and Victors hardness tester, and compared with those of the sintered monolithic body. Many dislocations were observed in the Ni phase due to the difference of thermal expansion coefficient between and Ni phase, and no observed microcracks at their and Ni interface. In the /Ni composite, the main fracture mode showed a mixed fracture with intergranular and transgranuluar type having some ,surface roughness. The fracture toughness was slightly increased due to the plastic deformation mechanism of Ni phase in the /Ni composite.

This studies were performed to develop a Korean traditional folk liquor namely Gangha-ju has been prepared at Bosung district in Korea, and manufacturing conditions and anti-oxidation activity and anti-microbial activity of Gangha-ju were investigated. Ethyl-alcohol 20% and 30% Gangha-ju were brewed with glutinous rice wine, distilled liquor and 6 herbs of ginger, cinnamon, etc. Chemical and physical properties of 30% Gangha-ju were acidity 0.22, pH 4.31, amino acidity 3.26, transmittance 59 and conductivity 911 μs/m, and 20% Gangha-ju were 0.43, 4.20, 6.26, 62 and 924 μs/m. Volatile flavor compounds of ethyl alcohol, acetic acid, butanol, n-amyl alcohol, iso-pentyl alcohol, ethyl acetate, butyl acetate, acetaldehyde and furfural were detected, and main aroma compounds of Gangha-ju were isopentyl alcohol and ethyl acetate. Anti-oxidation activity by DPPH method was evaluated 31.32%, and nitrite scavenging effect was 31.79%. Anti-microbial activity against several microorganisms was pronounced strong activity over a wide range of test organisms, and Leuconostoc mesenteroids and Salmonella Ttyphimurium, Staphylococcus epidermidis were found to be more sensitive to Gangha-ju than Escherichia coli and Aspergillus flavus.

In the present study, imbedded copper matrix powders have been successfully prepared from the () composite salt solution. The composite powders were formed by drying the solution at 200~40 in the hydrogen atmosphere. Photocatalytic characteristics was evaluated by detecting TOC (total organic carbon) amount with TOC analyzer (model 5000A Shimadzu Co). Phase analysis of composite powders was carried out by XRD, DSC and powder size was measured with TEM. The mean particle size of composite powders was about 100 nm and a few zinc and copper oxide phases was included. The reduction ratio of TOC amount was 60% by the composite powders under the UV irradiation for 8 hours

nanopowder was synthesized by chemical vapor condensation (CVC) process and its photocatalytic property depending on microstructure was considered in terns of decomposition rate of organic compound. In order to control microstructure of nanopowder such as particle size and degree of agglomeration, precursor flow rate representing number concentration was changed as a process variable. In TEM observation, spherical nanoparticles with average size of 20 nm showed gradual increases in particle size and degree of agglomeration with increase of precursor flow rate. Also decomposition rate of organic compound increased with decreasing precursor flow rate. Thus, it was concluded that photocatalytic property was enhanced by targe surface area of disperse nanoparticles synthesized at lower precursor flow rate condition in CVC process

WC and dense WC-10 vol%Co materials with grain size of~1 were synthesized by high-frequency induction heated combustion synthesis (HFIHCS) method in one step from elemental powders of W, C and Co within several minutes. Simultaneous combustion synthesis and densification were accomplished under the combined effects of an induced current and mechanical pressure. In the absence of cobalt additive, WC can be formed, but its relative density was low (about 73%) under simultaneous application of a 60 MPa pressure and the induced current. However, in the presence of 10 vol.%Co, the relative density increased to 99% under the same experimental condition. The percentages of the total shrinkage occurring before and during the synthesis reaction of WC-10 vol.%Co were 5% and 51%, respectively. The fracture toughness and hardness values of WC-10 vol.%Co were 10 MPa . m and 1840 kg/, respectively.

Aluminum-based composites were fabricated by a powder-in sheath rolling method. A stainless steel tube with outer diameter of 12 mm and wall thickness of 1 mm was used as a sheath. A mixture of aluminum powder and particles of which volume content was varied from 5 to 20%, was filled in the tube by tap filling and then rolled by 75% reduction in thickness at ambient temperature. The rolled specimen was then sintered at 56 for 0.5 h. The mixture of Al powders and particles was successfully consolidated by the sheath rolling. The composite fabricated by the sheath rolling showed a recrystallized structure, while unreinforced Al powder compact fabricated by the same procedure showed a deformed structure. The unreinforced Al powder compact was characterized by a deformation (rolling) texture of which main component is {112}<111>, while the composite showed a mixed texture oi deformation and recrystallization. The sintering resulted in recrystallization in Al powder compact and grain growth in the composite.

The powder-in sheath rolling was applied to the fabrication of composite. A stainless steel tube with outer diameter of 12 mm and wall thickness of 1 mm was used as a sheath. Mixture of aluminum powder and particles of which volume content was varied from 5 to 20 vol.% was filled in the tube by tap filling and then rolled to 75% reduction at ambient temperature. The re]]ed specimen was sintered at 56 for 0.5 hr. The composite fabricated by the sheath rolling and subsequent sintering showed the relative density higher than 0.96. The tensile strength of the composite increased with the volume content of particles, and it reached a maximum of 90 MPa which is 1.5 times higher than unreinforced material. The elongation decreased with the volume content of particles. It is concluded that the powder-in sheath rolling is an effective method for fabrication of composite.

Nanocrystalline materials of Ni and Ni-Cu alloy have been synthesized by the pulsed wire evaporation (PWE) method and these abnormal magnetic properties in the magnetic ordered state have been characterized using both VSM and SQUID in the range of high and low magnetic fields. Ni and Ni-Cu particles with an average size of 20 to 80 nm were found to influence magnetic hysterisis behavior and the results of powder neutron diffraction patterns and saturation magnetization curves are shown to indicate the absence of the NiO phase. The shifted hysterisis loop and irreversibility of the magnetization curve in the high field region were observed in the magnetic-ordered state of both Ni and Ni-Cu. The virgin magnetization curve for Ni slightly spillover on the limited hysterisis loop (20kOe). This irreversibility in the high field of 50 kOe can be explained by non-col-linear behavior and the existence of the metastable states of the magnetization at the surface layer (or core) of the particle in the applied magnetic field. Immiscible alloy of Cu-Ni was also found to show irreversibility having two different magnetic phases.