• Journal of Conservation Science
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• v.36 no.2
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• pp.112-122
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• 2020

The purpose of this study was to find out the correlation through comparative analysis of used materials and manufacturing techniques such as firing characteristics for sherds excavated from celadon kiln site in Punggil-ri, Jangheung. The color difference of the sherds was very wide, and even in the microstructure of the cross section of the glaze layer and the body layer, the celadons, whitewares, blackware, and stonewares could not be characterized because they did not show distinct differences from each other. As a result of estimating the firing temperature through the analysis of constituent minerals and thermal analysis, most of them were estimated to have been fired at 1000℃, but some were fired at high temperatures above 1200℃. It was difficult to clearly distinguish between celadon and whiteware even in the major compositional content of bodies. In the statistical analysis, glaze could be classified three group according to the type of sherds, but the bodies of celadons, whitewares, and blackware classified into one similar group. It is considered that it is not more likely differences in raw materials but some ingredients were removed or added during the purification process. Conclusionally, in this kiln site was found through scientific analysis that there were technical attempts to produce various ceramics, and that the manufacturing techniques and materials of ceramics were in an early stage that was not stabilized.

• Korean Journal of Food Science and Technology
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• v.21 no.1
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• pp.58-62
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• 1989

Free amino acids in water-extracts and total amino acids in hydrolysates of three cultivated mushrooms, Agaricus bisporus, Pleurotus ostreatus and Lentinus edodes were analyzed by amino acid analyzer to know the compositional differences depending on species and portions (pileus and stipe). Eighteen amino acids were identified and quantified. The total nitrogen and protein nitrogen contents were in the range of 1.67-6.24% and 0.88-2.42% (dry basis), respectively. The considerable differences were often found among species and portions of mushrooms. All of them were found to be higher in the pileus part. The free amino acids conents in water-extracts were in the range of 10.04-37.85mg/g(dry weight) and the total amino acids contents in hydrolysates were in the range of 53.37-120.15mg/g(dry weight). Glutamic acid, serine, histidine, and alanine were dominent in the free amino acids pool and glutamic, aspartic acid, histidine, and alanine were in the total amino acids pool.

• Economic and Environmental Geology
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• v.49 no.2
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• pp.105-120
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• 2016

Most of riverside in Korea, in case of application of water curtain cultivation (WCC) technique, has been inveterately suffering from the gradual drawdown of groundwater level and related shortage of water resources during the WCC peak time. We believe that the water resources issue in these riverside areas can be effectively solved when the interaction between groundwater and nearby surface water is well understood. To investigate the connection between stream and ground water, and the influence of stream water on the nearby aquifer, this study examined the water temperature and oxygen and hydrogen stable isotopic compositions. The study area is well-known strawberry field applying the WCC technique in Sangdae-ri, Gadeok-myon, Cheongju City, and the sampling was done from February 2012 through June 2014 for stream and ground water. Some groundwater wells near stream showed big temporal variations in water temperature, and their oxygen and hydrogen stable isotopes showed similar compositions to those of adjacent stream water. This indicates that the influence of stream water is highly reflected in the stable isotopic composition of groundwater. Four cross-sectional lines from stream to hillside were established in the study area to determine the spatial differences in water quality of wells. At the late stage of WCC in February to March, groundwater of wells in line with short cross-sectional length showed the narrow range of isotopic compositions; however, those in the long cross-sectional line showed a wide compositional range. It was shown that the influence of the stream water at the late WCC stage have reached to the distance of 160 to 165 m from stream line, which is equivalent to the whole length and one-third point in each short and long cross-sectional line, respectively. Therefore, the wide compositional range in the long cross-sectional lines was not only due to the influence of stream water, but apparently resulted from the change of relative impact of each groundwater supplying from two or more aquifers. In view of stable isotopic compositions, there seems to be three different aquifers in this study area, which is competing for dominance of water quality in wells at each period of WCC.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.100-105
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• 1988

Composition of organic acids and fatty acids in three edible mushrooms, Pleurotus ostreatus, Lentinus edodes and Agaricus bisporus were analyzed by gas-liquid chromatography and compositional differences of these components depending on species, sizes and portions (pileus and stipe) were investigated. Lactic, oxalic. fumaric. citric and pyroglutamic acid were identified in each of the three mushrooms and the major organic acids were malic, citric and pyroglutamic acid, respectively. The total organic acid contents were in the range of 2.4-4.0% in Pleurotus ostreatus, 1.7-3.6% in Lentinus edodes and 1.9-3.1% in Agaricus bisporus. Especially oxalic and pyroglutamic acid in Pleurotus ostreatus, malic and citric acid in Lentinus edodes and fumaric acid in Agaricus bisporus were higher in pileus than stipe. The total organic acid contents decreased as the size of pileus developed and especially the decrease of citric acid were marked. On the other hand, the major fatty acids in three mushrooms were linoleic, palmitic and oleic acid. But fatty arid compositions were not significantly different depending on species, sizes and portions.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1523-1523
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• 2001

The wine industry requires practical methods for objectively measuring the composition of both red wine grapes on the vine to determine optimal harvest time; and of freshly harvested grapes for efficient allocation to vinery process streams for particular red wine products, and to determine payment of contract grapegrowers. To be practical for industry application these methods must be rapid, inexpensive and accurate. In most cases this restricts the analyses available to measurement of TSS (total soluble solids, predominantly sugars) by refractometry and pH by electropotentiometry. These two parameters, however, do not provide a comprehensive compositional characterization for the purpose of winemaking. The concentration of anthocyanin pigment in red wine grapes is an accepted indicator of potential wine quality and price. However, routine analysis for total anthocyanins is not considered as a practical option by the wider wine industry because of the high cost and slow turnaround time of this multi-step wet chemical laboratory analysis. Recent work by this ${group}^{l,2}$ has established the capability of near infrared (NIR) spectroscopy to provide rapid, accurate and simultaneous measurement of total anthocyanins, TSS and pH in red wine grapes. The analyses may be carried out equally well using either research grade scanning spectrometers or much simpler reduced spectral range portable diode-array based instrumentation. We have recently expanded on this work by collecting thousands of red wine grape samples in Australia. The sample set spans two vintages (1999 and 2000), five distinct geographical winegrowing regions and three main red wine grape varieties used in Australia (Cabernet Sauvignon, Shiraz and Merlot). Homogenized grape samples were scanned in diffuse reflectance mode on a FOSE NIR Systems6500 spectrometer and subject to laboratory analysis by the traditional methods for total anthocyanins, TSS and pH. We report here an analysis of the correlations between the NIR spectra and the laboratory data using standard chemometric algorithms within The Unscrambler software package. In particular, various subsets of the total data set are considered in turn to elucidate the effects of vintage, geographical area and grape variety on the measurement of grape composition by NIR spectroscopy. The relative ability of discrete calibrations to predict within and across these differences is considered. The results are then used to propose an optimal calibration strategy for red wine grape analysis.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.6 no.2
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• pp.238-246
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• 1996

High-density SiC-AIN solid solutions were fabricated from powder mixtures of $\beta$-SiC and AIN by hot-pressing in the 1870 to $2030^{\circ}C$ temperature range. The reaction of AIN and $\beta$-SiC (3C) powder transformed to the 2 H (wurzite) structure appeared to depend on the temperature and SiC/A1N ratio and seeds present. The crystalline phases consisted of a SiC-rich solid-solution phase and an A1N-rich solid-solution phase. At $2030^{\circ}C$ for 1 h, for a composition of 50 % AIN/50 % SiC with a seeding of $\alpha$-SiC, the complete solid solution could be obtained and the microstructures are equiaxed with a relatively homogeneous grain size of 2 H phases. The variation of the seeding of $\alpha$-SiC in SIC-A1N solid solutions could be attributed to the transformation behaviour and differences in size and shape of the grains, as well as to other factors, such as grain size distributions, compositional inhomogeneity, and structural defects.

• Journal of Life Science
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• v.19 no.10
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• pp.1468-1477
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• 2009

The comparative effects of the fibrinolytic, and tyrosinase inhibition activities and electrophoretical protein patterns with freeze-drying silkworm powder (FDSW), heating-drying silkworm powder (HDSW) and fermented silkworm powder by Bacillus subtilis or Lactobacillus hilgardii were investigated. When total protein patterns of FDSW, HDSW, both fermented SW, were analyzed by native- and SDS-polyacrylamide gel electrophoresis (PAGE), there were slightly varietal differences in electrophoretical protein patterns. Major minerals of FDSW and HDSW were K, Ca, Mg, and Zn. Major compositional amino acids of FDSW and HDSW were glycine, alanine, glutamic acid, aspartic acid, and serine. Major fatty acids of FDSW and HDSW were linolenic acid, oleic acid, and palmitic acid. Fibriolytic activity was the highest in the fermented FDSW by 5% B. subtilis among the various samples. Tyrosinase inhibition activity was higher in the water and 70% methanolic extract of FDSW than in HDSW. DPPH radical scavenging activity was slightly stronger in HDSW than in FDSW. In addition, DPPH radical scavenging activity was higher in FDSW or HDSW fermented by L. hilgardii than that fermented by B. subtilis, however, all samples exhibited a relatively low activity compared to the butylated hydroxytoluene (BHT). These results may provide the basic data to understand the biological activities of fermented SW.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.539-550
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• 2014

The purpose of this study was to determine the optimal mixing ratios of three different ingredients of Polygonum multiflorum Radix powder, butter, and sugar for the development of recipe for cookies with Polygonum multiflorum Radix powder. Response surface methodology based on a five level and three variables by central composite design was employed to obtain the best possible combination for the ratios of Polygonum multiflorum Radix powder ($X_1$), butter ($X_2$), and sugar ($X_3$). The analytical results of the physical and mechanical properties for each sample including color L (P<0.01), color a (P<0.01), color b (P<0.01), spread ratio (P<0.001), and hardness (P<0.001) showed significant differences. The sensory measurements were significantly different in color (P<0.05), appearance (P<0.05), texture (P<0.001), flavor (P<0.01), taste (P<0.01), and overall quality (P<0.001). The optimal compositional ratios were determined to be 4.00 g for the Polygonum multiflorum Radix powder, 75.42 g for the butter, and 45.67 g for the sugar.

• Journal of Conservation Science
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• v.36 no.5
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• pp.405-420
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• 2020

A convergence research was conducted on glass beads excavated at the ruins of Hapgang-ri, Sejong, using the archeology and conservation approach. The period of appearance of Jugu Towangmyo in the ruins of Hapgang-ri can be estimated to begin in the late 2^nd century; for Jugu Towangmyo No. 15, the period spans from the late 2^nd to early 3^rd century. Form, color, and manufacturing techniques of complete glass beads were examined, and the cross-sections and chemical composition of 16 samples were observed. Based on these analyses, the glass beads were divided into blue, purple, and red colors. The blue-colored beads could be further sub-divided based on their gloss and brightness; in contrast, the red-colored beads were highly uniform with regard to these parameters. Based on the stripe and bubble arrangement on the surface of the glass beads, their drawing technique was identified. Traces of heat treatment or polishing were observed at the ends of the beads. According to their chemical composition, the 16 samples were classified into 3 potash glass and 13 soda glass groups; in the latter, the properties of the stabilizers were divided according to the blue and red bead colors. The stabilizers of the red beads are unique in that they allow the distinction among beads excavated in other areas in South Korea owing to their compositional differences. Colorants in blue- and red-colored beads are cobalt (containing MnO), and copper and iron, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.5
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• pp.810-814
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• 2004

This research was conducted to evaluate the safety of the herbicide-resistant rice, a genetically modified organism (GMO) developed by the Rural Development Administration by exposing it to 12 months old Sprague-Dawley rats for 8 weeks. The composition of herbicide-resistant brown rice with/without heating treatment was compared with those of conventional Ilpum brown rice with/without heating treatment to assess composition equivalence. Compositional analysis was performed to measure proximates, fiber, and minerals. The nutritional components of herbicide-resistant rice were similar to those of the nontransgenic control or were within the normal range of nontransgenic rice. Four groups of experimental male rats were fed one of the following diets for eight weeks: Ilpum brown rice (I) and its heated rice (IH) as non-GMO, and herbicide-resistant brown rice (G) and its heated rice (GH) as GMO- We checked clinical symptoms (anorexia, salivation, diarrhea, polyuria, anuria, fecal change), food intake, and water consumption every day, change of body weight once a week, and serum biochemistry and organ weights after 8 weeks of experimental feeding We did not find any significant differences in the above-mentioned items. These results suggested that genetically modified herbicide-resistant rice was compositionally equivalent to conventional Ilpum rice, and nutritional characteristics and safety of herbicide-resistant rice in old male rats treated for 8 weeks were not different from those of Ilpum rice, non-GMO.