• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.3
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• pp.66-72
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• 2011

The annals of Joseon Dynasty is one of UNESCO's Memory of the World Register. For the safety preservation of the waxed annals of Joseon Dynasty, the acidic and alkaline aging mechanism of beeswax and beeswaxed Hanji has been investigated. The weight loss of beeswaxed Hanji by the acidic aging was higher than those of alkaline beeswax. The acid value and relative intensity of carbonyl groups in beeswax were slowly increased with aging time. The strength of dewaxed Hanji was decreased with aging time. The significant changes of crystallinity of dewaxed Hanji by acidic and alkaline aging were not observed.

• Journal of Powder Materials
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• v.9 no.5
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• pp.365-369
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• 2002

Silica hydrogel was synthesized by the reaction of liquid sodium silicate with sulfuric acid. The condensation polymerization of the synthesized hydrogel was carried out via an aging process under the acidic or alkaline conditions. Nano porous silica with the pore size below 3 nm and surface area of $715m^2/g$, was obtained by the above processes in acidic ranges(pH : 3~5). The pore size and surface area of the silica varied with pH, and in alkaline ranges(pH : 8~10), those were 21 nm and $300m^2/g$ respectively. The characteristics of the silica varied with the thermal treatment which caused the change of surface area, pore volume and pore diameter.

• Journal of Korean Society of Archives and Records Management
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• v.1 no.1
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• pp.177-200
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• 2001

The causes which affects the deterioation of paper arc paper structure, papermaking process, temperature and rative humidity, light and biological agents. Paper made from cllulose fibers by the wood and the nonwood, This paper structure is further hydrolyzed by acidic additive such as the sizing agents during the manufacturing process. These additives leave residual acids in the paper, which break the cellulose clown to simper molecules. The results is weak paper and bas caused most of the damage to book. This study was carried out to investigate the presevation and the deacidification for the permanenece by the book. The deacidification and the chemical agents aims to nutralized the aicd in paper and add alkaline to it as a buffer to withstand future acid attacks. By applying the system to the acid paper with a pH of 4.5 neutralized a pH of 8.5. The expected of alkaline reserved paper extend about 2times and 3times than acidic paper.

• Korean Journal of Food Science and Technology
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• v.27 no.1
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• pp.56-62
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• 1995

This study was designed to investigate the changes in microflora and enzyme activities of traditional kochujang meju during fermentation for 60 days. The pH of meju decreased continously up to 40 days of aging and then increased slightly thereafter, while the change in titratable acidity showed the opposite trend to that of pH. The viable cell count of aerobic bacteria increared gradually for up to 40 days of fermentation and then decreased slightly thereafter, while that of molds and yeasts showed a rapid increase up to 40 days of fermentation and then leveled off. ${\alpha}-amylase$ activity increased slightly for up to 40 days of meju fermentation and then stabilized. On the other hand, ${\beta}-amylase$ and glucoamylase activities did not show a significant change for up to 20 days of fermentation and then increased rapidly at 40th day of fermentation. Acidic, neutral and alkaline protease activities increased sharply up to 40 days of aging and then decreased significently at 60th day of fermentation. These results suggest that meju fermented for 40 days had the highest quality in terms of the number of microflora and enzyme activity.

• Journal of Korea Foresty Energy
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• v.21 no.2
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• pp.25-33
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• 2002

One of the critical problems to preserve books and documents in libraries and archives is the deterioration. Some of previous results showed that the major cause of paper deterioration was the acid-catalyzed hydrolysis of the cellulose in paper fibres and aging rate of acidic paper was faster than that of alkaline paper. Therefore, It is necessary to remove the acid in the paper for reducing the rate of paper deterioration. It has been reported to extend the useful life of acidic paper by three to five times. Recently, It has been recognized the need for an effective method of deacidifying large quantities of books and document. However, in the previous many reports little attention was paid to the effect of paper additives. In this paper, We carried out experiment about the effect of additives on paper aging and the effect of deacidification by the gaseous ethanolamines (monoehtanolamine, diethanolamine, triehtanolamine). In result, it was found that the strength of aging was in the order of the alum＋rosin＞alum ＞AKD＞ control and the rate of deacidification was in the order of the monoethanolamine＞diethanolamine＞triethanolamine. The treatment with the gaseous ethanolamines caused decreasing of brightness and dropping of fold endurances. However, deacidification by combination treatment of the various gaseous ehtnaolamines prevented from decreasing of brightness and dropping of folding endurances.