• Korean Journal of Materials Research
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• v.8 no.12
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• pp.1182-1189
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• 1998

High quality $TiN/TiSi_2$-bilayers were formed on the Si(100) substrate at room temperature and at $600^{\circ}C$ first by coevaporation of stoichiometric Si and Ti(Si:Ti = 2:1) fellowed by Ti reactive deposition in N, gas ambient, and in situ annealing in ultrahigh vacuum. Stoichiometric $Ti_{0.}N_{0.5}$, films with (111) texture and $C54-TiSi_2$ films were grown by annealing at temperatures above $700^{\circ}C$. $TiN/C54-TiSi_2$/Si(100) interface was clear and flat without agglomoration, and $CS4-TiSi_2$ film was epitxailly grown. The sheet resistance of the $TiN/TiSi_2$- bilayer decreased as the annealing temperature increased and about $2.5\omega/\textrm{cm}^2$ was obtained from the sample annealed over $700^{\circ}C$.

• Applied Chemistry for Engineering
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• v.22 no.3
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• pp.312-318
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• 2011

We have investigated the kinetics and catalytic activity of $CO_2$-lignite gasification with various metal precursors as catalysts. $K_2CO_3$, $Mn(NO_3)_2$, and $Ce(NO_3)_3$ were used and impregnated on a coal using an evaporator. The gasification experiments were carried out with the low rank coal loaded with 5 wt% catalyst at the temperature range from $700{\sim}900^{\circ}C$ and atmospheric pressure with the $N_2-CO_2$ reactant gas mixture. The catalytic effect on the gasification rate of the low rank coal with $CO_2$ was determined by the thermogravimetric analyzer. It was observed that the low rank coal reached the complete carbon conversion regardless of the kinds of catalysts at $900^{\circ}C$ from the results of TGA. The catalytic activity was ranked as 5 wt% $K_2CO_3$ > 5 wt% $Mn(NO_3)_2$ > 5 wt% $Ce(NO_3)_3$ > Non-catalyst at $900^{\circ}C$. The gasification rate increased with increasing the temperature. The activation energy of the catalytic gasification with 5 wt% $K_2CO_3$ was 119.0 kJ/mol, which was the lowest among all catalysts.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.8
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• pp.1141-1149
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• 2011

The objective of this study was to analyze quality changes during storage of fresh-cut produce (leafy vegetables and condiment vegetables) as a function of packaging and storage temperature. Fresh-cut produce was washed using a three step cleaning process and was packed in vacuum packaging (green onion, hot pepper, onion, baechu) and perforated film packaging (buchu and perilla leaf). The effects of packaging method and storage temperature on quality of fresh-cut produce were determined by analyzing total plate counts, E. coli, coliform groups, moisture content, pH, Aw, surface color, and exterior quality during storage at 4 and 10$^{\circ}C$. According to the results, surface color change and microbial growth were delayed during storage at 4$^{\circ}C$. Additionally, E. coli was not detected during storage. Generally, moisture content decreased in the perforated film packaging. Changes in surface quality such as skin browning, softening of tissue and chlorosis at 4$^{\circ}C$ were inhibited, whereas rapid vacuum annealing and changes in color and flavor were observed in the sample stored at 10$^{\circ}C$. The result indicated that overall quality of the fresh-cut produce at 4$^{\circ}C$ was well maintained. The perforation in packing materials did not significantly increase the number of microorganisms on buchu and perilla leaf. The proper packaging methods and temperature may beneficial effect on microbial safety, quality and thus result in longer shelf-life fresh-cut vegetables during distribution.