• Journal of Conservation Science
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• v.32 no.4
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• pp.511-520
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• 2016

The purpose of this study was to estimate the firing temperature of fired clay brick by applying high temperature X-ray diffraction(XRD) analysis. The clay bricks, which were excavated from a Buddhist temple in Karatepa, Uzbekistan were composed of quartz, plagioclase, alkali feldspar, mica, chlorite, limestone, hornblende, etc. Some clay bricks contained gypsum, which was presumed to have been used to improve the adhesive strength of the brick. Estimating the firing temperature using a geologic thermometer, the UZ-1 sample was identified as being in the quartz, plagioclase, pyroxene series, and the firing temperature was estimated to be $900-1200^{\circ}C$. On the other hand, applying the high temperature XRD method to the UZ-5 sample, it was found that the limestone was destroyed at $1000^{\circ}C$ and the diffraction peak of chlorite was weakened at $1050^{\circ}C$. Moreover, pyroxene series minerals developed at $1050^{\circ}C$ in the reproduction experiment. These results indicate that the clay bricks used in the temple were produced in a kiln that reached a temperature of more than $1000^{\circ}C$. Thus, high temperature XRD analysis can more accurately estimate firing temperatures as compared to the firing temperature mineral identification method and it can be used to determine the creation and extinction temperature range of minerals.

• Journal of Conservation Science
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• v.34 no.2
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• pp.119-128
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• 2018

This study revealed the material composition and characteristics of 19 glass fragments excavated from stone chamber No. 1 of Jeongchon Tomb in Naju through chemical composition analyses and observations. These characteristics were compared with the characteristics of the glass fragments excavated from No. 3 tomb of Bogam-ri in Naju. The purpose of this study was to identify the characteristics of the ancient glass of the Mahan-Baekje period. The glass fragments excavated from the Jeongchon Tombs can be classified into purplish blue, light-purplish blue, greenish blue, green, and mixture of purple blue and purple, based on their color. These beads were made using a drawn and casting technique. In addition, blue glass fragments were primarily excavated form No. 3 tomb of Bogam-ri. However, red glass fragments were not excavated from either of the tombs. According to chemical composition analyses, soda glass group and potash glass group were common in both the tombs. Additionally, alkali mixed glass group and lead barium glass group were excavated from Jeongchon Tombs and No. 3 tomb of Bogam-ri, respectively. The glass fragments excavated from No. 3 tomb of Bogam-ri have more color variations than those excavated from Jeongchon Tombs.

• Applied Biological Chemistry
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• v.18 no.2
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• pp.65-70
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• 1975

The cultivation of ginseng plant (Panax ginseng C.A. Meyer) in Korea as an eminent medicinal herb may be traced far back in history. However, the practices in cultivation have not much improved in terms of efficiency and scientific farming. In the present study some experiments were undertaken for the search of the soil and nutrition conditions, because of the nutritional requirement of ginseng plant shaws quite unique compared with other crops. In both the seed bed and the field 'Yakto' has been traditionally employed or the prime source of nutrition of the crop. Yakto is a complex matter prepared from raw foliage of the broad-leaved trees as the main portion with the admixture of a variety of organic nitrogen source through fermentative processes. The composition of Yakto may be classified coarsely into the decomposed and undecomposed substances, the former being further fractionated according their solubilities, comprising also various colloidal matters whose composition and structure are yet to be known. The Yakto-fractions were subjected to analyze for search of its nature and coarse composition in terms of the distribution of nitrogen, contents of organic functional groups such as -COOH, phenolic-OH, alcholic-OH and methoxyl and hydrolysable sugars. Furthermore, absorption-spectra of each fraction were determined in visible and infrared region and compared the results each other.

• Applied Biological Chemistry
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• v.18 no.2
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• pp.98-101
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• 1975

The components of Gardenia pigment in rind, flesh, fresh fruit and stored fruit, its heat resistance and stability in pH, its dilution and colour-degree were studied. The results are summarized as follows; 1. The components of CROCIN in fresh fruit and stored fruit were 0.0157% and 0.0136% respectively. One year storage of stored fruit resulted in the decrease of 15% of CROCIN. 2. The components of Gardenia pigment in flesh were contained nearly twice as much as in rind. 3. There were traces of ${\beta}-carotene$ and some unknown carotenoid pigments. 4. Gardenia pigment was stable at $100^{\circ}C$ for 60 minutes, but, at $150^{\circ}C$ for 30 minutes, nearly half of them was destructed. 5. Gardenia pigment turned to colurless but was stable in neutral or alkali condition after 10 days. 6. Supercially, dark Gardenia pigment looked yellowish red and thin Gardenia pigment looked yellow: however, each ${\lambda}_{max}$. was all the same.

• Applied Biological Chemistry
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• v.19 no.3
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• pp.155-161
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• 1976

The say sauce koji where made use of different kinds of seed koji were used to brewing of soysauce. The pure, complex and bacteria contaminated seed koji were used in this experiment, And the euzyme activity, Micrflora, chemical composition and TN-solubility ratio of each soysauce mash during the fermentation periods were measured respectively. The results obtained were as follows. 1. The neutral and alkali protease activity of each soysauce mash were decreassed in the process of fermentation period. In this case the activitities of protease in the bacteria contaminated koji were remarkably decreased. 2. The microflora in one ml of soysauce mash showed the tendency of increase in process of fermentation period. The increase in bacteria contaminated seed koji group was remarkable. 3. The content of total nitrogen, amino-N and ammonia-N in soysauce during the course of fermentation were increase. And alcohol, reducing sugar and pure extract contents in soysauce were also increased in the former stage of fermentation, but in the latter stage of fermentation decreased. 4. Though the content of ammonia-N in bacteria contaminated seed koji group was high, the pH value was low in comparison with the others. 5. Pure seed koji group were shown the most effective in the result of total nitrogen solubility ratio and sensual test, while the bacteria contaminated seed koji group was the worst.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.258-261
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• 1991

In order to establish the optimum drying temperature of the heated air blast-grain circulation dryer, a 2 ton scale of paddy was used in this experiment. The temperatures of heated air used were 45, 50, 55, 60, 65 and $70^{\circ}C$. Moisture content of the paddy was reduced to 15% from 24% by drying. The higher air temperature, the shorter drying time and the less fuel consumed. The portion of cracked kernels was found to be low as $3{\sim}10%\;at\;40{\sim}55^{\circ}C$, but was very high to $28{\sim}30%\;at\;60{\sim}70^{\circ}C$. The germination percent was very high as 98 and 93% at 40 and $45^{\circ}C$, but it was decreased to 86 and 30% at 50 and $70^{\circ}C$, respectively. The recovery yield of milled rice from paddy was decreased by 1.76, 2.63 and 7.52% at 60, 65 and $70^{\circ}C$, respectively, compared with 75.86% as drying at $40^{\circ}C$. The higher heated air temperature, the less head rice of milled rice was recovered, and the decreased ratio was increased $60^{\circ}C$. The higher heated air temperature, the less alkali disintergation value and gel consistency of milled rice and the more water up take, expanded vlume, total solid in residual liquid and intensity of starch iodine blue value of residual liquid, and those tendency was found clear from $60^{\circ}C$ temperature of heated air.

• Microbiology and Biotechnology Letters
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• v.15 no.2
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• pp.129-134
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• 1987

Aspergillus sp. (MK-24) producing a biological active substance that inhibited the venom proteinase activity was isolated from soil. The substance also inhibited the activity of trypsin and coagulation of blood, but did not inhibit papain, $\alpha$-chymotrypsin and pepsin. The substance was partially purified from culture filtrate by precipitaion with acetone, and by chromatography of DEAE-Sepadex A-50 column and Amberlite IRC-50 ion exchange. The inhibitory substance was stable in the wide pH range from 2.0 to 12.0 at 37$^{\circ}C$, but not stable at $65^{\circ}C$ in the alkaline pH. Only 12% of the activity was decreased by the heat treatment at 10$0^{\circ}C$ for two hours. The inhibition on venom proteinase (Agkistrodon bromohoffi brevicaudus) was a mixed type. The inhibitory activity depended on the preincubation time and completely depressed by cupric, zinc and cobalt ions. The inhibition on the venom proteinase was appeared strongly on casein but not on ovalbumin or hemoglobin as a substrate.

• Journal of the Korean Applied Science and Technology
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• v.33 no.4
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• pp.634-646
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• 2016

In this work, modified epoxy resins which were well melted in mild solvent were synthesized and solubility assessment was carried out for synthesized epoxy resins. Bisphenol-A type, phenol novolac type and ortho-cresol novolac type epoxy resins were used and fatty acid, dodecyl phenol (DP) and toluene diisocyanate (TDI) were added for synthesis of modified epoxy resins containing fatty acid (MEFA). Composition was epoxy resin/fatty acid = 1.0/0.5 and fatty acid/DP = 0.25/0.25 by equivalent weight and twelve MEFAs were synthesized according to epoxy resins. Viscosity and solubility were measured for twelve MEFAs. As a result, solubility of MEFA was excellent for mild solvent according to increasement of contents of benzene ring, glycidyl group and carbon number of alkyl group. And physical properties were measured for each coating of paints after preparing transparent paints of MEFA to melt well in mild solvent among twelve MEFAs. As a result, they showed an optimal performance on conditions of equivalent ratio of bisphenol-A type epoxy resin/fatty acid/DP/TDI; 1.0/0.25/0.25/0.5 and equivalent ratio of phenol novolac type epoxy resin/fatty acid/DP; 1.0/0.25/0.25 for drying time, adhesion, hardness, impact resistance and alkali resistance.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.33-40
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• 1994

Effects of blanching on protein composition and texture in geoduck muscle during frozen storage at $-20^{\circ}C$ were investigated. In frozen muscle, sarcoplasmic protein and myofibrillar protein were decreased, while alkali-soluble protein increased rapidly. During the storage of the blanched muscle(at $95^{\circ}C$ for 2 min.), sarcoplasmic and myofibrilla protein showed slow decreases. The muscle blanched for 2 min(BM) showed the best texture among the samples treated with various blanching times(at $95^{\circ}C$ for 1, 2, 3, and mins). In comparing the textures of BM with raw muscle, hardness of BM was similar raw muscle, and elasticity and stress relaxation of BM revealed lower levels than those of raw muscle, but break elongation and toughness were higher. In the changes of texture of raw muscle and BM during the frozen storage, as the storage time lengthened, hardness and toughness of both muscles were stronger, and both stress relaxations showed greatly decreases during initial storage(7 days), and break elongation level of raw muscle showed rapid increases in 100 days but there were no changes in that of BM, Elasticity of raw muscle gradually reduced during storage while that of BM increased.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.24 no.1
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• pp.15-20
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• 2014

In this research, the geopolymer was fabricated using municipal solid waste incineration ash (denoted as MSWIA) slag and alkali activator, NaOH and its properties were analyzed. Particularly, the effects of NaOH molarity, particle size of MSWIA, and liquid/solids ratio on the compressive strength of geopolymers were investigated. The compressive strength of geopolymers fabricated increased with finer grain size of MSWIA, and optimum value of the liquid/solids ratio was identified as 0.13. As the molarity of the NaOH increased, the compressive strength of geopolymers was increased. Even more the 20 M of NaOH, but the strength was not increased. The calcium aluminum silicate and calcium aluminum silicate hydrate zeolites were generated in the geopolymer fabricated with more than 20 M of NaOH, with some unreacted silica and unknown crystals remained. The highest compressive strength, 163 MPa, of geopolymer was appeared at conditions of curing temperature $70^{\circ}C$, and 20 M of NaOH, indicating that the high concentration of NaOH accelerates the geopolymer reaction and dense microstructure. The high-strength geopolymer fabricated in the present study is expected to contribute significantly to develop the field of cement alternative substances and to improve the recycling rate of MSWIA slag.