• Applied Biological Chemistry
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• v.24 no.1
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• pp.50-58
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• 1981

The influence of high temperature storage on the chemical composition and color intensity of the concentrated red ginseng extract(RGE) was investigated. The concentrated RGE was prepared by extraction of red ginseng tails with water and concentrated under reduced pressure. Changes in free sugars, saponin patterns and brown color intensity were measured during 96 hours of heat treatment at various temperature. A decrease in the contents of glucose, fructose and sucrose was resulted as the brown color intensity increased during the storage. The sugar contents and color intensity showed rapid initial change followed by slowing down at higher temperature. A significant relationship was found between sugar content and browning rate. The saponin pattern measured by high performance liquid chromatography, particularly in the region of protopanaxtriol, was also affected significantly. The peak heights of ginsenoside -Re and $-Rg_1$ were decreased while those of ginsenoside $-Rg_2$ and -Rh group were increased.

• Korean Journal of Environmental Agriculture
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• v.34 no.2
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• pp.105-110
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• 2015

BACKGROUND: Soy isoflavones, structurally similar to endogenous estrogens, may affect human body through both hormonally mediated and non-hormonally related mechanisms. Heat processing could change chemical compositions. The effects of different thermal processes, boiling and HTHP(high temperature and high pressure) on the composition of isoflavone compounds and total amount of domestic soybeans were investigated in this study. METHOD AND RESULTS: Three different kinds of soybean samples were collected from RDA-Genebank. The samples were extracted using methanol, distilled water, and formic acid based solvent. Also the same solvents were used for mobile phase in UPLC/ToF/MS. All of the isoflavone compounds were analyzed based on the aglycone type of external standard for quantification. The standard calibration curve presented linearity with the correlation coefficient R2 > 0.98, analysed from 1 to 50 ppm concentration. The total isoflavone contents does not change by treatment within the same breed. While "boiling" and "HTHP" processes tend to increase the contents of aglycone and ${beta}$-glucosides, "fresh" soybeans retained the high concentration of malonylglucosides. CONCLUSION: These results have to be considered while developing an effective functional food, from the health while point of view using soybeans.

• 한국신재생에너지학회:학술대회논문집
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• 2005.06a
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• pp.663-666
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• 2005

Gas hydrates are ice-like compounds that form at the low temperature and high pressure conditions common in shallow marine sediments at water depths greater than 300-500 m when concentrations of methane and other hydrocarbon gases exceed saturation. Estimates of the total mass of methane carbon that resides in this reservoir vary widely. While there is general agreement that gas hydrate is a significant component of the global near-surface carbon budget, there is considerable controversy about whether it has the potential to be a major source of fossil fuel in the future and whether periods of global climate change in the past can be attributed to destabilization of this reservoir. Also essentially unknown is the interaction between gas hydrate and the subsurface biosphere. ODP Leg 204 was designed to address these questions by determining the distribution, amount and rate of formation of gas hydrate within an accretionary ridge and adjacent basin and the sources of gas for forming hydrate. Additional objectives included identification of geologic proxies for past gas hydrate occurrence and calibration of remote sensing techniques to quantify the in situ amount of gas hydrate that can be used to improve estimates where no boreholes exist. Leg 204 also provided an opportunity to test several new techniques for sampling, preserving and measuring gas hydrates. During ODP Leg 204, nine sites were drilled and cored on southern Hydrate Ridge, a topographic high in the accretionary complex of the Cascadia subduction zone, located approximately 80km west of Newport, Oregon. Previous studies of southern Hydrate Ridge had documented the presence of seafloor gas vents, outcrops of massive gas hydrate, and a pinnacle' of authigenic carbonate near the summit. Deep-towed sidescan data show an approximately $300\times500m$ area of relatively high acoustic backscatter that indicates the extent of seafloor venting. Elsewhere on southern Hydrate Ridge, the seafloor is covered with low reflectivity sediment, but the presence of a regional bottom-simulating seismic reflection (BSR) suggests that gas hydrate is widespread. The sites that were drilled and cored during ODP Leg 204 can be grouped into three end-member environments basedon the seismic data. Sites 1244 through 1247 characterize the flanks of southern Hydrate Ridge. Sites 1248-1250 characterize the summit in the region of active seafloor venting. Sites 1251 and 1252 characterize the slope basin east of Hydrate Ridge, which is a region of rapid sedimentation, in contrast to the erosional environment of Hydrate Ridge. Site 1252 was located on the flank of a secondary anticline and is the only site where no BSR is observed.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.3
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• pp.225-232
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• 2013

The inorganic insulating material was fabricated with quartzite, ordinary portland cement(OPC), lime, anhydrous gypsum and foaming agent by hydrothermal reaction. The inorganic insulating material was fabricated by using autoclave chamber under high-temperature and high-pressure. The inorganic insulating material is a porous lightweight concrete. Because of its porous structure, properties of inorganic insulating material were light-weight and high-heat insulation property. Properties of fabricated inorganic insulating material were $0.26g/cm^3$ in specific gravity, 0.4MPa in compressive strength and 0.064W/mK in thermal conductivity. In this study, the inorganic insulating material was fabricated and analyzed at different size of quartzite/OPC, various foaming reagent and functional additives to improve the properties. Consequently, polydimethylsiloxane can improve density and thermal conductivity. Especially, polydimethylsiloxane showed excellent improvement in compressive strength.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.45 no.3
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• pp.207-214
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• 2012

This study was conducted to optimize the processing conditions, including the ingredient ratio and extraction time, for a water-soluble fraction of Alaska pollock head and non-forming sea tangle by response surface methodology. Our results indicated that the optimal independent variables for obtaining extracts with a high yield and desirable sensory characteristics were 1.32 for $X_1$ (extraction time), 1.36 for $X_2$ (sea tangle concentration) and 0.93 for $X_3$ (water volume) in coded values, and 5.48 h for $X_1$, 18.18% for $X_2$ and 6.86 times for $X_3$ in uncoded values. The predicted values of $Y_1$ (yield), $Y_2$ (TCA soluble-N) and $Y_3$ (overall acceptance) for extracts produced under these optimized conditions were 22.10%, 1.83 g/100 mL and 5.9, respectively, their experimental values were 21.4%, 1.7 g/100 mL and 5.7, respectively. No significant differences between the actual and predicted values were found.

• Clean Technology
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• v.23 no.4
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• pp.357-363
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• 2017

In this study, the supercritical carbon dioxide ($scCO_2$)/ n-butyl acetate (n-BA) co-solvent system was employed to remove an unexposed negative photoresist (PR) from the surface of a silicon wafer. In addition, the selectivity of the $scCO_2$/n-BA co-solvent system was confirmed for the unexposed and exposed negative PR. Optimum conditions for removal of the unexposed PR were obtained from various conditions such as pressure, temperature and n-BA ratio. The n-BA was highly soluble in $scCO_2$ without cloud point and phase separation in mostly experimental conditions. However, the $scCO_2$/n-BA co-solvent was phase separated at 100 bar, above $80^{\circ}C$. The unexposed and exposed PR was swelled in $scCO_2$ solvent at all experimental conditions. The complete removal of unexposed PR was achieved from the reaction condition of 160 bar, 10 min, $40^{\circ}C$ and 75 wt% n-BA in $scCO_2$, as measured by ellipsometry. The exposed photoresist showed high stability in the $scCO_2$/n-BA co-solvent system, which indicated that the $scCO_2$/n-BA co-solvent system has high selectivity for the PR removal in photo lithograph process. The $scCO_2$/n-BA co-solvent system not only prevent swelling of exposed PR, but also provide efficient and powful performance to removal unexposed PR.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.2
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• pp.95-102
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• 2005

There are many tube and pipeline in nuclear power plant under high temperature and high pressure. Erosion and corrosion defects were expected on these tube and pipe-line by environmental and mechanical factors. These erosion and corrosion defects ran be evaluated by ultrasonic technique. In these study, Scanning Laser Source(SLS) technique was applied to detect defect and construct image. This technique also makes detection possible on rough and curved surfaces such as tube and pipe-line by scanning. Conventional ultrasonic scanning technique requires immersion of specimen or water jet for transferring ultrasonic wave between transducer and specimen. However, this SLS technique does not need contacting and couplant to generate surface wave and to get flaw images. Therefore, this SLS technique has several advantages, for complicated production inspection, non-contact, remote from specimen, and high resolution. In this study, SLS images were obtained with various conditions of generation laser ultrasound and receiving in order to enhance detectability of flaws on the tube. Stress corrosion cracks were produced on tube and images of stress corrosion cracks were constructed by using SLS technique.

• 한국해양학회지
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• v.22 no.3
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• pp.207-215
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• 1987

The Keum River Estuary was investigated two times in April and July, 1986, to study process controlling chlorophyll distribution in estuarine waters. During the surveys, distribution patterns were studied for chlorophyll-a, nutrients, ph, SPM (Suspended Particulate Matter), DO (Dissolved Oxygen), temperature, salinity, etc. During April survey(low-discharge period), sea water penetrated to Kangkyung, about 35km upstream from the constructing weir, while in July (high-discharge period) only to 3 km upstream from the weir,In April SPM showed very high concentrations (500mg/l)on the average. But very low concentrations(about10mg/l)were observed in July due to high discharge of fresh water.Chlorophyll-a concentrations showed large variations both in time and space :much higher concentraations in July than in April and sharp decrease in concentrations at the fresh water-sea water interface (April:$6.5\mu\textrm{g}/{\ell}$ for fresh waters and 41.4\mu\textrm{g}/{\ell}$ forestuarine waters). Differebce ub chlorophyll-a concentrations for these two surveys appear to be caused mainly by the difference in effectiveness of penetrating lights controlled by SPM in the waters. Sharp decrease in chlorophll-a at the fresh water-sea water interface is believed to be resulted from mass mortality of fresh water phytoplankton caused by changes in osmotic pressure in the region. Observations in the same regions such as increase in AOU(Apparent Oxygen Utilization)and ammonia, decrease in PH,probably resulted through decomposition processes of dead planktons,furtuer support the idea.

• Journal of Environmental Science International
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• v.15 no.8
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• pp.701-718
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• 2006

The average ratio of the daily UV-B to total solar (75) irradiance at Busan (35.23$^{\circ}$N, 129.07$^{\circ}$E) in Korea is found as 0.11%. There is also a high exponential relationship between hourly UV-B and total solar irradiance: UV-B=exp (a$\times$(75-b))(R$^2$=0.93). The daily variation of total ozone is compared with the UV-B irradiance at Pohang (36.03$^{\circ}$N, 129.40$^{\circ}$E) in Korea using the Total Ozone Mapping Spectrometer (TOMS) data during the period of May to July in 2005. The total ozone (TO) has been maintained to a decreasing trend since 1979, which leading to a negative correlation with the ground-level UV-B irradiance doting the given period of cloudless day: UV-B=239.23-0.056 TO (R$^2$=0.52). The statistical predictions of daily total ozone are analyzed by using the data of the Brewer spectrophotometer and TOMS in East Asia including the Korean peninsula. The long-term monthly averages of total ozone using the multiplicative seasonal AutoRegressive Integrated Moving Average (ARIMA) model are used to predict the hourly mean UV-B irradiance by interpolating the daily mean total ozone far the predicting period. We also can predict the next day's total ozone by using regression models based on the present day's total ozone by TOMS and the next day's predicted maximum air temperature by the Meteorological Mesoscale Model 5 (MM5). These predicted and observed total ozone amounts are used to input data of the parameterization model (PM) of hourly UV-B irradiance. The PM of UV-B irradiance is based on the main parameters such as cloudiness, solar zenith angle, total ozone, opacity of aerosols, altitude, and surface albedo. The input data for the model requires daily total ozone, hourly amount and type of cloud, visibility and air pressure. To simplify cloud effects in the model, the constant cloud transmittance are used. For example, the correlation coefficient of the PM using these cloud transmissivities is shown high in more than 0.91 for cloudy days in Busan, and the relative mean bias error (RMBE) and the relative root mean square error (RRMSE) are less than 21% and 27%, respectively. In this study, the daily variations of calculated and predicted UV-B irradiance are presented in high correlation coefficients of more than 0.86 at each monitoring site of the Korean peninsula as well as East Asia. The RMBE is within 10% of the mean measured hourly irradiance, and the RRMSE is within 15% for hourly irradiance, respectively. Although errors are present in cloud amounts and total ozone, the results are still acceptable.

• Journal of the Korean earth science society
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• v.38 no.2
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• pp.129-140
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• 2017

Global solar radiation was calculated in this research using ground-base measurement data, meteorological satellite data, and GWNU (Gangneung-Wonju National University) solar radiation model. We also analyzed the accuracy of the GWNU model by comparing the observed solar radiation according to the total cloud cover. Our research was based on the global solar radiation of the GWNU radiation site in 2012, observation data such as temperature and pressure, humidity, aerosol, total ozone amount data from the Ozone Monitoring Instrument (OMI) sensor, and Skyview data used for evaluation of cloud mask and total cloud cover. On a clear day when the total cloud cover was 0 tenth, the calculated global solar radiations using the GWNU model had a high correlation coefficient of 0.98 compared with the observed solar radiation, but root mean square error (RMSE) was relatively high, i.e., $36.62Wm^{-2}$. The Skyview equipment was unable to determine the meteorological condition such as thin clouds, mist, and haze. On a cloudy day, regression equations were used for the radiation model to correct the effect of clouds. The correlation coefficient was 0.92, but the RMSE was high, i.e., $99.50Wm^{-2}$. For more accurate analysis, additional analysis of various elements including shielding of the direct radiation component and cloud optical thickness is required. The results of this study can be useful in the area where the global solar radiation is not observed by calculating the global solar radiation per minute or time.