• Economic and Environmental Geology
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• v.48 no.2
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• pp.147-160
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• 2015

In 2014, on 31 August and 1 September, the emissions of $CH_4$, $CO_2$, and $O_2$ gases were measured six times using the closed chamber method from exposed tidal flat sediments in the same position relative to the low point of the tidal cycle in the Eoeun-ri, Taean-gun, on the Mid-western Coast of Korea. The concentrations of $CH_4$ in the air sample collected in the chamber were measured using gas chromatography with an EG analyzer, model GS-23, within 6 hours of collection, and the other gases were measured in real time using a multi-gas monitor. The gas emission fluxes (source (+), and sink (-)) were calculated from a simple linear regression analysis of the changes in the concentrations over time. In order to see the surrounding parameters (water content, temperature, total organic carbon, average mean size of sediments, and the temperature of the inner chamber) were measured at the study site. On the first day, across three measurements during 5 hours 20 minutes, the observed $CO_2$ flux absorption was -137.00 to $-81.73mg/m^2/hr$, and the $O_2$ absorption, measured simultaneously, was -0.03 to $0.00mg/m^2/hr$. On the second day using an identical number of measurements, the $CO_2$ absorption was -20.43 to $-2.11mg/m^2/hr$, and the $O_2$ absorption -0.18 to $-0.14mg/m^2/hr$. The $CH_4$ absorption before low tide was $-0.02mg/m^2/hr$ (first day, Pearson correlation coefficient using the SPSS statistical analysis is -0.555(n=5, p=0.332, pronounced negative linear relationship)), and $-0.15mg/m^2/hr$ (second day, -0.915(n=5, p=0.030, strong negative linear relationship)) on both measurement days. The emitted flux after low tide on both measurement days reached a minimum of $+0.00mg/m^2/hr$ (+0.713(n=5, p=0.176, linear relationship which can be almost ignored)), and a maximum of $+0.03mg/m^2/hr$ (+0.194(n=5, p=0.754, weak positive linear relationship)) after low tide. However, the absolute values of the $CH_4$ fluxes were analyzed at different times. These results suggest that rate for $CH_4$ fluxes, even the same time and area, were influenced by changes in the tidal cycle characteristics of surface sediments for understanding their correlation with these gas emissions, and surrounding parameters such as physiochemical sediments conditions.

• Korean Journal of Heritage: History & Science
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• v.42 no.1
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• pp.88-99
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• 2009

This study was conducted to formulate management guidelines for Natural monumental old trees in Korea through survey of tree vigor and analysis of growing environments. A total of 20 old trees designated as natural monuments in Seoul, Incheon, and Gyeonggi Province were surveyed. The biological characteristics were surveyed with 4 items of species, ages and height of trees. The surrounding environments were surveyed with 2 items of location types and surroundings. The root conditions were surveyed with 2 items of denudation and molding depth. The health conditions were surveyed with 5 items of withering rate, cavity size, bark breakaway rate, damages by blight and insects, and growing tips. The soil conditions were surveyed with 6 items of PH, organic contents, valid phosphoric acid, transposal cations(K, Ca) and soil compaction. On the basis of outcomes of these research items, mutual relations among locations, growings and soil conditions of old trees were analyzed by carring out cross tabulation, correlation, and simple and multiple regression. Management guidelines were presented searching the factors effecting on the health of the monumental old trees. On the biological characteristics, the old trees designated as natural monuments were Pinus bungeana(4 trees), Juniperus chinensis(3 trees), Ginkgo biloba(3 trees), Poncirus trifoliata(2 trees). Actinidia arguta, Wisteria floribunda, Thuja orientalis, Quercus mongolica, Sophora japonica, Fraxinus rhynchophylla, Zelkova serrata, and Pinus densiflora. The tree height ranged from 4.2 to 39.2m, and root collar rounds ranged from 1.01 to 15.2m. On the surrounding environments, The location types ; Gardens(4), historical sites(5), residental sections(3) open agricultural fields(3), mountain hills(3), and near ocean beaches(1) and stream site(1). The surroundings ; 75% denudation of roots, molded more than 10cm except 4 trees(25%). On the health conditions, 1)Withering rate ; Ginkgo biloba(20%) in Yongmoon temple, (5%) in Saki-ri, kanwha-gun, and others had no withering rate. 2) Cavity size ; all subject had $5{\sim}100cm^3$ of cavity. 3) Bark breakaway rate ; Pinus bungeana in Soosong-dong, in the shrine of Confucius, in Samchung-dong, especially high rate of cavity(5~50%) in Seoul area and in Saki-ri, Kangwha-gun were high 45% brakeaway rate. 4) Damages by blight and insects was slight due to managements. 5Growing tips ; In cases of Juniperus chinensis in Changdeok palace and SunnogDang, seoul, growing tips were 1/2, presumably cause by air pollution, and in cases of Fraxinus rhynchophylla in Paju city and Pinus densiflora in BacksaDorip-ri, Icheon city, growing tips were fine, presumably because there were no moldings. On the Soil conditions, Soil pH ranged from 5.2 to 8.3, organic matter contents from 12% to 56%, phosphorus contents from 104 to 618ppm, soil compaction ranged from 7 to 28mm( among them, Denudation was severe with 21~28mm soil compactions in cases of Pinus bungeana in Soosong -dong, Thuja orientalis in Samchung -dong, Ginkgo biloba in the shrine of Confucius and in Yongmoon temple.) Results of cross tabulation, correlation, and regression analysis showed that molding depth was the most serious factor to deteriorate the tree vigor and cambium conductivity. In addition, soil acidity, organic matter contents, disease and insect damages and cambial detachment were also related to the tree vigor. Additional research of these relationships will be needed to conduct more detailed studies. Based on the relationships between the tree vigor and growing environments, it is considered that old trees should be managed to give them more growing spaces and less abuses. Also, molded soils should be removed and further soil-molding around the tree collar should be prohibited. For the construction of systematic management and removal of harmful factors, appropriative management according to spices, persistent monitering of damaged cases and construction of management system through the accumulation of data on the relationships of soil conditions are required.

• The Journal of Engineering Geology
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• v.19 no.4
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• pp.529-541
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• 2009

Hydrochemical, stable isotopic ($\delta^{18}O$ and dD) and noble gas isotopic analyses of seven hot spring water samples, eleven groundwater samples and six surface water samples collected from the Icheon and Pocheon area were carried out to find out hydrochemical characteristics, and to interpret the source of noble gases and the geochemical evolution of the hot spring waters. The hot spring waters show low temperature type ranging from 21.5 to $31.4^{\circ}C$ and the pH value between 6.69 and 9.21. Electrical conductivity of hot spring waters has the range from 310 to $735\;{\mu}S/cm$. Whereas the hot spring water in the Icheon area shows the geochemical characteristics of neutral pH, the $Ca-HCO_3$(or $Ca(Na)-HCO_3$) chemical type and a high uranium content, the hot spring water in the Pocheon area shows the characteristics of alkaline pH, the $Na-HCO_3$ chemical type and a high fluorine content. These characteristics indicate that the hot spring water in the Icheon area is under the early stage in the geochemical evolution, and that the hot spring water in the Pocheon area has been geochemically evolved. The $\delta^{18}O$ and ${\delta}D$ values of hot spring waters show the range of $-10.1{\sim}-8.69%o$ and from $-72.2{\sim}-60.8%o$, respectively, and these values supply the information of the recharge area of hot spring waters. The $^3He/^4He$ ratios of the hot spring waters range from $0.09\;{\times}\;10^{-6}$ to $0.65\;{\times}\;10^{-6}$ which are plotted above the mixing line between air and crustal components. Whereas the helium gas in the Icheon hot spring water was mainly provided from the atmospheric source mixing with the mantle(or magma) origin, the origin of helium gas in the Pocheon hot spring water shows a dominant crustal source. $^{40}Ar/^{36}Ar$ ratios of hot spring water are in the range of an atmosphere source.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.149-160
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• 2013

The objective of present study was to simultaneously isolate of isoflavone and soyasaponin compounds from the germ of soybean seeds. Soy germ flours were defatted with hexane for 48h at room temperature, and methanolic extracts were prepared using reflux apparatus at $90^{\circ}C$ for 6h, two times. After extraction, extracts were separated with preparative RP-$C_{18}$ packing column ($125{\AA}$, $55-105{\mu}m$, $40{\times}150mm$), and collected 52 fractions were identified with TLC plate (Kieselgel 60 F-254) and HPLC, respectively. Among the identified isoflavone and soyasaponin fractions, isoflavone fractions were re-separated using a recycling HPLC with gel permeation column (Jaigel-W252, $20{\times}500mm$). Final fractions were air-dried, and the purified compounds of two isoflavones (ISF-1-1, ISF-1-2) and four soyasaponins (SAP-1, SAP-2, SAP-3, SAP-4) were obtained. Two isoflavone compounds (ISF-1-1, ISF-1-2) were acid-hydrolyzed for the identification of their aglycones, and confirmed by comparing with 12 types of isoflavone isomers. While the four kinds of soyasaponins were identified by using a micro Q-TOF mass spectrometer in the ESI positive mode with capillary voltage of 4.5kV, and dry temperature of $200^{\circ}C$. Base on the obtained results, it was conclude that ISF-1-1 is the mixture isomers of daidzin (43.4%), glycitin (47.0%), and genistin (9.6%), but ISF-1-2 is the single compound of genistin (99.8% <). On the other hand, soyasaponin SAP-1 is the mixture compounds of soyasaponin A-group (Aa, Ab, Ac, Ae, Af); SAP-2 is soyasaponin B-group (Ba, Bb, Bc) and E-group (Bd, Be); SAP-3 is soyasaponin B-group (Ba, Bb, Bc), E-group (Bd, Be), and DDMP-group (${\beta}g$); SAP-4 is soyasaponin B-group (Ba, Bb, Bc), E-group (Bd, Be), and DDMP-group (${\beta}g$, ${\beta}a$), respectively.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.265-272
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• 2002

Forage breeding laboratory of National Livestock Research Institute, R.D.A. has made interspecific hybrids of Lolium multiflorum $\times$ L. pratensis and intergeneric hybrids of Lolium $\times$ Festuca since 1984, and has collected ecotypes of Italian ryegrass since 1991. Growth characteristics of these hybrids and ecotypes were researched, and then these clone lines were named. Among these clone lines, the several clones that have polen fertility, high cold-tolerance, and similar heading time were used for making synthetics, Naehan 6, 7, 8, 9, with polycrossing method in 1997. Field experiments were carried out to compare the mophological and agronomical characteristics and forage productivity and quality of the synthetics with those of Italian ryegrass varieties, Barmultra and Hwasan 101. in Suwon and Yonchun from 1999 to 2000. Heading time of the synthetics were 22th to 24th May that belong to late-mature types to be similar to that of Barmultra and Hwasan 101 in Suwon. The synthetics were 101 to 106 c3n in plant length, medium or thick in thickness of stem, dark peen in leaf color, broad and long in flag leaf, strong in lodging resistance, and excellent in regrowth. Winter survivals of the synthetics were no different from that of Barmultra or Hwasan 101 in Suwon, but better than that of Barmultra or Hwasan 101 in Yonchun where was -10 to -12$^{\circ}C$ of minimum average air temperature in January or February. Dry matter(DM) yields of the synthetics were similar to DM 8,238kg per ha of Barmultra in Suwon, but in Yonchun, were more 7 to 13% than DM 7,291kg per ha of Barmultra. Forage qualities, IVDMD, ADF, NDF and TDN of the synthetics were lower than those of Hwasan 101, but higher than those of Barmultra.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.6 no.2
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• pp.81-92
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• 2001

According to analyses of high-resolution seismic profiles (air gun, sparker, and SBP) and a deep-drill core(YSDP 105) in the mid-eastern Yellow Sea, stratigraphic and geoacoustic models have been established and seismo-acoustic modeling has been fulfilled using ray tracing of finite element method. Stratigraphic model reflects seismo-, litho-, and chrono-stratigraphic sequences formed under a significant influence of Quaternary glacio-eustatic sea-level fluctuations. Each sequence consists of terrestrial to very-shallow-marine coarse-grained lowstand systems tract and tidal fine-grained transgressive to highstand systems tract. Based on mean grain-size data (121 samples) of the drill core, bulk density and P-wave velocity of depositional units have been inferred and extrapolated down to a depth of the recovery using the Hamilton's regression equations. As goo-acoustic parameters, the 121 pairs of bulk density and P-wave velocity have been averaged on each unit of the stratigraphic model. As a result of computer ray-tracing simulation of the subsurface strata, we have found that there are complex ray paths and many acoustic-shadow zones owing to the presence of irregular layer boundaries and low-velocity layers.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.578-583
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• 2010

Acid rain and its problem to environment such as acid precipitation and environmental problems related to the air pollution in East Asia has been emerging. To evaluate the acidity and chemical characteristics of rainwater precipitated in western Korea, Suwon and Taean, its pH and ion concentrations were investigated during farming season (April to November) in 2009. Also, ion composition and cation-affected neutralization were determined to evaluate the contribution of cations on the acidity of rainwater. Ion and electrical conductivity between the measured and the estimated showed high correlation. The $Na^+$ in rainwater was the main cation followed by ${NH_4}^+>Ca^{2+}>H^+>Mg^{2+}>K^+$. Sum of $Na^+$ and ${NH_4}^+$ contents was over 65% of total cations contents. In the case of anions, the concentration was in order of ${SO_4}^{2-}>{NO_3}^->Cl^-$. The ${SO_4}^{2-}$ among anions in rainwater composed about 61%, which showed on average 130.2 ${\mu}eq\;L^{-1}$ and 121.3 ${\mu}eq\;L^{-1}$ during monitoring at Suwon and Taean, respectively. Also, 89.6 and 88.6% of soluble sulfate in rainwater at Suwon and Taean area was NSS-${SO_4}^{2-}$ (Non-Sea Salt sulfate). Especially, ${NH_4}^+$ and $Ca^{2+}$ contributed greatly in neutralizing the acid rain in dry season. Total nitrogen content flowed into soil from rain was around 1~2 kg $ha^{-1}$ in each month, but in July at Suwon, it reached 6 kg $ha^{-1}$ due to heavy rain (over 7.3 mm).

• 한국해양학회지
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• v.23 no.1
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• pp.24-40
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• 1988

In the Korea Ocean Nodule Development (KONOD)-1 area between the Clarion and Clipperton fracture zones of the northeastern equatorial Pacific, the pelagic sediment layer can be divided into two or three units on air-gun seismic profile. The acoustic units can be also correlated with those in the DSDP site 163 core. The topmost unit (unit I) is acoustically transparent and consists of zeolitic clay and radiolarian ooze of late Oligocene to middle Eocene age. Unit IIA is well-stratified and transparent in the lower part. consisting of the radiolarian ooze intercalated with chert beds and zeolitic clay of early Eocene to Paleocene age. Unit IIB is stratified with layers of silicified and compacted flinty-cherty nannofossil chalk (late Cretaceous) on top of the acoustic basement. Units I and IIA form the Line Islands Formation that overlies an unnamed formation of unit lIB. The entire layers and the unit I layer propressively thin northward, except near the Line Islands Ridge. The distribution of sediment layer has been controlled by the equatorial Cenozoic CCD and the northward spreading of the Pacific plate. The change of CCD corresponding to the subsidence and migration of the plate has determined the sediment composition of the DSDP 163 core passed across the equator of high sedimentation suite. The late Cretaceous sedimentary layer (unit IIB) in the 163 core was formed above the CCD south of the equator. The unit IIA resulted from rapid subsidence of the Pacific plate below the CCD in the Paleocene. The unit IIA is seen only in the west of 149 W. Both the units IIA and I were probably formed during the Pacific plate passing and after leaving the equatorial region respectively since early Eocene. In the south of the KONOD-l area, the unit I was redistributed by bottom current, a branch of the Antarctic Bottom Water flowing eastward guided by the Clipperton fracture zone. The activities of bottom currents were prolonged for a long geological time. Turbidite layers occur more than 350 km from the Hawaiian Ridge to near the Clarion fracture zone. They originated directly from the Hawaiian Ridge, filling the topographic lows.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.2
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• pp.93-103
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• 2020

The average growth day of 11 maize varieties from planting to silking in the first cropping (FC) was 89.5 days and in the second cropping (SC) was 46.7 days, which was 43 days faster than in the FC. The average 100-kernel weight (100 KW) in the FC was 28.4 g and 18.3 g in the SC, which was approximately 36.4% lower than that in the FC. The average crude oil content of FC was 3.97% and SC was 3.08%, which was about 0.89% lower than that of FC. The composition of stearic and oleic acid was significantly higher in FC, whereas palmitic and linoleic acid were higher in SC; however, linolenic acid was not statistically different between the two crops. The crude oil content was negatively correlated with linoleic acid (FC -0.264^ns, SC -0.504**) and positively correlated with linolenic acid (0.526**). Unsaturated fatty acid (USFA) composition showed a significant difference between FC (83.48%) and SC (82.96%). Total phytosterol content was 598.3 mg/100 g and 701.9 mg/100 g in FC and SC, respectively, and showed significant difference by planting dates. The β-sitosterol content showed no statistical difference between the planting dates, but campesterol and stigmasterol were significantly higher in SC than in FC. Therefore, it was considered that the temperature condition during the ripening period affects the 100 KW of maize, and this leads to the variation in phytosterol content. However, among phytosterols, β-sitosterol was relatively little affected by the planting dates. USFA composition showed a significantly negative correlation with phytosterol content. Considering the results, the relatively high phytosterol content in SC was mainly because of the delay in progress of starch accumulation as daily air temperature decreased from the middle of the ripening period, whereas progress of phytosterol accumulation in the maize kernel was considered relatively faster than that of starch accumulation.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.44 no.3
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• pp.211-218
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• 2018

Instant face lifting cosmetics contain various film forming agents for stretching the wrinkles on the skin surface. But, most of the film-forming polymers have sticky feels. And they are easily scrubbed out when skin is rubbed on. In this study, we focused on the influence of sodium silicate that has rapid film forming effect on skin surface and immediate wrinkle reducing effect. Sodium silicate, also known as water glass or soluble glass, is a compound containing sodium oxide and silica. Sodium silicate is a white powder that is readily soluble in water, producing an alkaline solution. Sodium silicate is stable in neutral and alkaline solutions. The sodium silicate solution hardens by drying in air and rapidly forms a thin film. When the solution is applied to the skin, the fine membrane coating is formed by water evaporation and ionic bond re-formation. It also makes the strong siloxane (Si-O) bonding on the skin surface. When these fixation properties are applied to cosmetics, they can give remarkable skin tightening effect. The sodium silicate solution can provide the lifting effect by forming a film on skin at a proper concentration. But, skin irritation may be caused with too high concentration of sodium silicate. We studied a desirable range of the sodium silicate concentration and combination with other fixatives for skin care formulation that has no sticky feels and no scrubbing out phenomenon. Immediate lifting gel was developed by using sodium silicate and various thickening systems. Among of the various thickeners, aluminum magnesium silicate showed the best compatibility with sodium silicate for rapid lifting effect. This instant physical lifting gel was confirmed as a low stimulating formula by skin clinical test.