Ultraweak photons could be emitted from the chemical reaction without any electromagnetic radient. These chemiluminescence could be detected by highly sensible photomultiplier recently. We will introduce the principal of chemiluminescence generation reaction, and the application studies in the determination of food-borne microorganisms in field. The counts of surface contaminated microorganism in mackeral and chicken for cold storage determined by ATP-chemiluminescence method had good correlation with the counts by standard agar plate method. However, there was little correlation between 2 methods in ginseng powder whose microbial counts were lower than 10,000 CFU.

Field emission display(FED) is actively investigated in view of the development of full color flat-panel display, which can replace some cathode-ray tube(CRT). Thus, the development of new phosphors appropriate for FED is urgently needed and has been actively investigated. In this work, SrTiO3:Pr3+ phosphor was prepared by sol-gel method and the coating was applied by sol-gel method combined with sonication on these phosphor's surface into diluted precursor solution. It was found that very fine particles of coating material were formed on phosphor's surface. The luminescent intensity of SrTiO3:Pr3+ phosphor coated with SiO2 and Al2O3 was considerably increased without any noticeable change in color chromaticity. The optimum concentration of coating material was found to be 1wt% and the optimum pH value of the solution was 10.

Y2-xGdxO3:Eu, phosphors for plasma display panel(PDP), were prepared by Pechini method which use yttriun chloride, gadolinium chloride, and europium oxide as starting materials. This method is a different way to the synthesis of europium(Eu)-doped phosphors, and it consists of the formation of a polymeric resin obtained by polyesterification between metal chelate compounds and a polyfunctional alcohol. This needs lower temperature than solid-state synthetic method. The prepared Y2-xGdxO3:Eu phosphor particles had spherical shape and coherence. The luminescence intensity of Y2-xGdxO3:Eu phosphor particles increased according to the increase of gadolinium(Gd) content(to 0.8mol%), and Y1.2Gd0.8O3:Eu phosphors had the highest luminescence intensity under vacuum ultra violet(VUV) excitation. The optimum concentration of Eu in the phosphor and optimum calcination temperature was 3wt% and 1100℃. The prepared phosphors were consist of particle, and its size was between 100nm and 150nm. Among the different polyfunctional alcohols, diethylene glycol(DEG) improved the luminescence intensities of phosphors more than other additives. The Pechini method proved that it is demonstrated to be suitable for the synthesis of phosphors used in PDP.

염산매질에서 산화/환원제를 사용하여 Pu 산화수를 조절한 후, UV-Visible-Near IR 분광기를 이용하여 Pu(III, IV, V, VI) 산화수에 대한 흡수스펙트럼을 측정하여 그 분광학적 특성을 고찰하였다. Pu(III)으로 조절하기 위하여 환원제인 HCl를 사용하였으며, Pu(IV)와 Pu(VI)로 조절하기 위하여 산화제인 및 를 각각 사용하였다. 또한 Pu(VI)로 조절된 용액에 환원제인 HCl를 사용하여 Pu(V)로 조절하였다. Pu(III)와 Pu(IV)의 대표적인 흡수피크는 470 nm 및 600 nm에서 각각 관찰되었고, Pu(VI)와 Pu(V)의 특성피크는 830 nm 및 1135nm에서 각각 관찰되었다. Pu(III, IV, VI) 산화상태의 시간 경과에 따른 흡수스펙트럼 변화는 관찰되지 않았으나 Pu(V)의 경우 매우 불안정하여 생성되자 마자 Pu(III)로 변화되었다.

Through the volume change of Sn in a low-temperature phase transformation, the Sn nanopowder with high, purity, was fabricated by an economic and eco-friendly process. The fine cracks were spontaneously generated. in, Sn ingot, which was reduced to powders in the repetition of phase transformation. The Sn nanopowder with 50 run in size was obtained by the 24th repetitions of phase transformation by low-temperature and ultrasonic treatments. Also, the powder was fabricated by the oxidation of the produced Sn powder to the ingot and milled by the ultrasonic milling method. The nanopowder of 20 nm in size was fabricated after the milling for 180 h

The particle reinforced composite fabricated by a powder-in sheath rolling (PSR) method was severely. deformed by the accumulative roll-bonding (ARB) process. The ARB process was performed up to 8 cycles at ambient temperature without lubricant. The ARBed composite exhibited an ulbricant. grained structure similar to the other ARBed bulky materials. Tensile strength of the composite increased gradually with the number of ARB cycles, but from the 6th cycle it rather decreased slightly. These characteristics of the composite were somewhat different from those of Al powder compact fabricated by the same procedures. The difference in microstructure and mechanical properties between Al powder compact and the composite was discussed

본 연구는 해양사고 피해규모에 의해 우리나라 수색·구조 구역의 위험수준을 평가하였다. 위험수준 평가를 위해서 전문가 지식에 기반한 퍼지로직, 퍼지측도 및 t-준노름 퍼지적분법을 이용하였다. 본 연구의 퍼지로직은 퍼지 확장원리에 의한 최대최소화 합성이고, 비퍼지화는 무게중심법을 이용하였고, 최종 평가는 t-준노름 퍼지적분법을 이용하였다. 그 결과 목포, 통영, 여수 수색·구조 구역의 위험수준이 가장 높은 것으로 평가되어, 향후 위험수준을 경감하기 위해 많은 구조선과 구조장비가 필요 할 것으로 판단된다.

In the present study, silver-doped antibacterial hydroxyapatites were successfully prepared by the sol-gel method. For the starting solution, the molar ratio of was set to 0.075:0.045:20:0.135; was added to a ratio of Ag to total cation concentration of . The prepared sol was dried at for 48h and heat-treated at for 2h to obtain particles in the 200-500nm size range. The product from the synthesis of silver-doped hydroxyapatite was investigated through X-ray diffraction experiments and scanning electron microscopy. The product showed high antibacterial properties, with a disinfection ratio of Staphylococcus aureus (ATCC 6538) and Escherichia coli (ATCC 25922) over as calculated from an antimicrobial effects evaluation by the shake flask method.