• Applied Biological Chemistry
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• v.18 no.2
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• pp.102-108
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• 1975

Acorn starch preparation and some of its characteric study were made. The results obtained were as follows. 1) Yearly production of acorn in Korea is amounted to be 1,200,000 l approximately. The content of its carbohydrate was found to be 72.8%, so that this would be considered as one of good resources of starch in our country. 2) The major moieties of tannin constituents of acorn were found to be the gallic acid, catechin and chlorogenic acid. 3) The type of acorn starch granules were short oval shaped having the diameters of that were in the range of $3.5{\sim}5.2{\mu}$ and $8.0{\sim}19.5{\mu}$, respectively. 4) Initial gelatinifalion teniperaiure of acorn starch was $62{\sim}64^{\circ}C$, similar to those of corn and wheat starch. 5) Alnylose content of acorn starch were 27.1%, which is lower than that of barley but higher than that of potato starch. 6) The raising power of the acorn starch was 12.4, which is higher than that of the potato starch but lower than those of common cereal starches. 7) The blue value of acorn starch was 0.43, similar to that of wheat starch and higher than those of wheat potato and rice starch but lower than that of barley starch. 8) The alkali number of the acorn starch was 11.03, similar to that of corn starch but higher than those of barley and rice starch.

• Journal of Korean Society of Transportation
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• v.23 no.8 s.86
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• pp.153-162
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• 2005

This study is carried out to evaluate the sight distance change due to construction errors of vertical crest curves. Various design speeds and grades as well as various size of construction errors are incorporated in this study. After showing theoretical methodology numerical results are compared and analysed for the given ranges of parameters. New vertical curve change rate(m/%) is suggested to guarantee minimum sight distance under construction errors. As to the results, the reduction of sight distance are $2.8{\sim}21.3m$ at 120km/h, $2.0{\sim}15.1m$ at 100km/h, $1.4{\sim}10.6m$ at 80km/h, $1.0{\sim}7.5m$ at 60km/h $0.5{\sim}3.9m$ at 40km/h. Vortical curve change rates need to be increased about $6{\sim}25%$ to provide minimum stopping sight distance according to design speed.

• Journal of the Korean Chemical Society
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• v.9 no.3
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• pp.116-120
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• 1965

The degree of atmospheric pollution from automobile engine exhausts has been measured at 1-ga, Eulchiro, Jung-ku, one of the heaviest traffic junctions in Seoul. By determining the concentrations of Pb, $SO_2, NO_2, NO, CO \;and\; CO_2$ in atmospheric air measured are as follows: Pb, $21{\sim}2 {\mu]g./m^3.;\;SO_2,\;0.33{\sim}0.001\;ppm.;\;NO_2,$ $0.20{\sim}< 0.01\;ppm.;\;NO,\;1.30{\sim}0.02\;ppm.;\;CO,\;40{\sim}<\;5ppm$.; and $CO_2,\;0.040{\sim}0.034%$. The mean concentrations determined are as follows: Pb, $11 {\mu}g./m^3.; SO_2, 0.08 ppm.; NO_2,$ 0.09 ppm.; NO, 0.37 ppm.; CO, 16 ppm. and $CO_2,$ 0.038%. Generally, the concentrations of Pb, $NO_2, NO, CO\; and\; CO_2$ are approximately proportional to the traffic density, vehicles passing per hour.

• Applied Chemistry for Engineering
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• v.7 no.2
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• pp.215-220
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• 1996

Nine kinds of amphoteric surfactants were derived from 1-(2-hydroxyethyl)-2-undecyl-2-imidazoline. Their surface activities including surface tension and isoelectric points were measured in aqueous solution and critical micelle concentration(cmc) was also evaluated by the measurement of surface tension. From the measurement of surface tension, carboxylated amides revealed to be 26~40dyne/cm at $4.0{\times}10^{-4}{\sim}1.0{\times}10^{-3}mol/{\ell}$, sulfonated or sulfated imidazolines, 30~35 dyne/cm at $1.5{\times}10^{-3}{\sim}2.5{\times}10^{-3}mol/{\ell}$ and sulfonated amides, 25~33 dyne/cm at $5.8{\times}10^{-4}{\sim}8.0{\times}10^{-4}mol/{\ell}$ concentration range. It was found that isoelectric points of carboxylated amides were pH 7.2~7.9 and those of sulfonated or sulfated imidazolines and sulfonated amides were pH 4.5~5.5.

• Journal of the Korean Society of Food Science and Nutrition
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• v.14 no.4
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• pp.365-369
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• 1985

In order to examine the effect of oil extraction methods on the characteristics of sesame oil, the unsaponifiable matters, fractionation sterol pattern and sterol compositions of the each fraction of the oil were compared in the oil extracted by the three different extraction methods, that is, pressure extraction of roasted seed (RTP), acetone extraction of roasted seed(RTE) and acetone extraction of raw seed(RWE). The amount of unsaponifiable in RWE oil was silghly higher as 31.8mg per 1mg drying oil than that in RTP oil of 26.1mg. Sesame oils from three different extraction methods were found to contain $0.26{\sim}0.32%$ free, $0.23{\sim}0.42%$ bound, and $0.49{\sim}0.64%$ total sterol. The content of free sterol in RWE oil was higher as 0.32% than that in RTE and RTP oil of 0.26%, and that of sterylglycoside in RTE oil was lower as 0.12% than that in RTP and RWE oil of 0.23%, but that of sterylester was a little difference. The unsaponifiable matter from fractionation sterol in sesame oil by three different extraction methods was fractionated into less polor compounds, 4,4-dimethyl-, 4-monomethyl-, 4-desmethylsterol fraction by thinlayer chromatography, and sterol composition of 4-desmethylsterol fraction was analyzed by gas liquid chromatography. The major sterols were campe-, stigma-, sito-, and ${\Delta}^5-avenasterol$, but, specially, unknown sterol(RRT:1.35) was found as $23.5{\sim}26.4%$ in total sterols, The content of sitosterol, ${\Delta}^5-avenasterol$, campesterol and stigmasterol were $59.9{\sim}60.3%,\;8.1{\sim}11%,\;16.1{\sim}18.4%,\;11.6{\sim}12.8%$ of the total sterol in free sterol fraction, $37.3{\sim}46.9,\;11.6{\sim}14.2,\;6.6{\sim}9.0$, and $6.1{\sim}8.0%$ of the total sterol in sterylglycoside fraction, $55.9{\sim}59.9,\;9.2{\sim}11.4,\;17.1{\sim}18.9$, and $11.8{\sim}13.7%$ of the total sterol in sterylester fraction, and $39.3{\sim}42.9,\;13.0{\sim}17.2,\;9.1{\sim}11.0$ and $7.4{\sim}11.5%$ of the total sterol in total sterol fraction. But the effect of oil extraction methods on sterol composition in sesame oil were hardly found.

• Korean Journal of Ecology and Environment
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• v.33 no.2 s.90
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• pp.176-186
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• 2000

The present study was carried out to clarify the structure and dynamics of copepod community and the relationship between this community and environmental factors during the period from February 1998 to July 1999. Copepods consists of 21 genera and 32 species, monthly variations of number of species were 15 species in May, 1998 and 2 species November, 1998. The number of species were 22 species in station 12 and station 1, 2, 3 occurred nauplii of copepoda only. Average abundance ranged from $8,330\;ind./m^3$ (in June, 1999) to $177\;ind./m^3$ (in November, 1998). Relationships between water temperature and number of species were as follows: 20 species occurred from 20.1 to $25.0^{\circ}C$ and nuplii of copepoda only occurred from 0.0 to $5.0^{\circ}C$. The number of species by salinity range were 19 species in $20.1{\sim}25.0%_o$ and 9 species in $0{\sim}0.5%_o$. The number of species by trophic state index (TSIm) of chlorophyll a were 25 species in oligotrophic state and 9 species in eutrophic state. Relationships between pH and number of species were as follows: 20 species occurred from 7.6 to 8.0 and from 9.1 to 9.5 was none. The number of species by DO range were 22 species in 6.5 to 7.5 mg/l and 1 species in 14.5 to 15.5 mg/l. The percentage calculated effect by stepwise multiple regression of the pearson correlation coefficient value of environmental factors and copepoda abundance (station 1-station 4) revealed that positive effect was 15.49% in COD, 25.86% in $Cl^-$, 19.75% in $NO_2-N$ and negative effect was 28.30% in $NO_3-N$. Also, Positive effect (station 5-station 12) revealed that 29.49% in water temperature, 28.27% in $NO_3-N$, 22.87% in $NO_2-N$ and negative effect was 30.18% in conductivity and 13.53% in DO.

• Journal of the Korean earth science society
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• v.22 no.6
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• pp.500-511
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• 2001

For the southeastern Korea aound the Yangsan fault we measured Q$_P^{-1}$ and Q$_S^{-1}$ simultaneously by using the extended coda-normalization method for seismograms registered at 9 stations deployed by KIGAM. We analyzed 707 seismograms of local earthquakes that occurred between December 1994 and February 2000. From seismograms, bandpass filtered traces were made by applying Butterworth filter with frequency-bands of 1${\sim}$2, 2${\sim}$4, 4${\sim}$8, 8${\sim}$16 and 16${\sim}$32 Hz. Estimated Q$_P^{-1}$ and Q$_S^{-1}$ values decrease from (7${\pm}$2)${\times}$10$^{-3}$ and (5${\pm}$4)${\times}$10$^{-4}$ at 1.5 Hz to (5${\pm}$4)${\times}$10$^{-3}$ and (5${\pm}$2)${\times}$10$^{-4}$ at 24 Hz, respectively. By fitting a power-law frequency dependent to estimated values over the whole stations, we obtained 0.009 (${\pm}$0.003)f$^{-1.05({\pm}0.14)$ for Q$_P^{-1}$ and 0.004 (${\pm}$0.001)f$^{-0.75({\pm}0.14)$) for Q$_S^{-1}$, where f is frequency in Hz.

• Korean Journal of Environmental Biology
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• v.31 no.1
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• pp.37-44
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• 2013

This study was to investigate water quality and biotic community characteristics in Juam Lake. In water quality, water temperatures was $3.8{\sim}21.2^{\circ}C$, 6.7~8.6 in pH, $64{\sim}76{\mu}s\;cm^{-1}$ in Conductivity, $5.3{\sim}13.2mg\;L^{-1}$ in DO, $2.5{\sim}3.3mg\;L^{-1}$ in COD, $1.0{\sim}5.1mg\;L^{-1}$ in SS, $0.622{\sim}0.841mg\;L^{-1}$ in T-N, $0.007{\sim}0.019mg\;L^{-1}$ in T-P and $2.8{\sim}8.8mg\;m^{-3}$ in Chl-a. Revised Carlson's Index (TSIm) assessment using total phosphorus (TP) and chlorophyll-a domonstrated that the trophic states of Juam Lake were rated as mesotrophic. A total of 53 species of phytoplankton were identified. They were 28 Bacillariophyceae, 13 Chlorophyceae, 3 Cyanophyceae, and 9 Other algal taxa. The standing crops of phytoplankton was ranged from $113cells\;mL^{-1}$ to $2,909cells\;mL^{-1}$. A total of 16 species of zooplankton were identified (10 rotifers, 4 cladocerans and 2 copepods). Total zooplankton abundance was $309ind.\;L^{-1}$ to $435ind.\;L^{-1}$. The collected benthic macroinvertebrates from the surveyed sites in Juam Lake were 1,038 individuals, 33 species, 21 families and 12 orders. A dominant species was Uracanthella rufa and a subdominant species was Ecdyonurus kibunensis. Hydrophytes recorded from Juam Lake were identified 9 taxa. Emerged plants, floating plants among the hydrophytes was classified 8, 1 taxa, respectively. Ecosystem disturbance wildplant by Environment Ministry found were Paspalum distichum var. distichum and Ambrosia artemisiaefolia. A total of 30 species (6 families) were collected fishs from Juam Lake. There were 10 Korean endemic species (33.3% of collected species number) and 3 exotic species (10.0%).

• Journal of fish pathology
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• v.9 no.1
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• pp.1-9
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• 1996

Many encysted metacercariae of Clinostomum complanatum(Rudolphi, 1814) were found in the flesh near the skin of goldfish(Carassius auratus) sultured at a fish farm in Chonbuk Province, Korea, in the summer of 1995. The mortality reached about 7% from July 10 to August 20. Encysted and excysted metacercariae were$700\sim877{\times}700\sim775{\mu}m$ and $2.4\sim5.5{\times}0.7\sim1.37{\mu}m$ in size, respectively. The parasites looked yellowish due to the yellow particulate matter in the intestine. Of 276 fish examined, 234(84.8%) were infected with a mean intensity of 216.6(range 1~1.214) parasites. Fish of 2.0~2.5 cm in body length were most frequently(94.3%) infected but those of 3.1~3.5 cm were the least infected(75.27%). The isthmus was most heavily infected. There was no difference in prevalence between two forms of goldfish, Gyariko an Ryugum. The sites of infection were swollen and recognized as yellow spots of 0.4~0.8 mm in diameter. Fish infected with more than 200 metacercariae became moribund with listless swimming and finally died.

• Journal of Embryo Transfer
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• v.22 no.2
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• pp.107-110
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• 2007

본 연구는 BPA 및 nicotine 첨가 농도와 배양 시간이 돼지 난자의 체외성숙에 미치는 영향을 조사하였다. $0.02{\sim}10.0mM$ BPA와 $0.5{\sim}10.0mM$ nicotine이 첨가된 TCM-199배양액에서 $40{\sim}52$시간 난자를 배양했을 때 체외성 숙율을 조사하였다. BPA농도가 높을수록 체외성숙율이 유의적으로 낮게 나타났다. $0.05{\sim}10.0nM$ BPA를 첨가한 TCM-199 배양액에서 난자를 44시간 배양했을 때 체외성숙율은 각각 $40.0{\pm}4.1%,\;24.0{\pm}4.7%,\;10.0{\pm}5.3%,\;6.0{\pm}3.2%,\;0.0{\pm}0.0%$로서 첨가 농도가 증가할수록 낮은 체외성숙율을 나타냈다. 난자를 $0.5{\pm}10.0mM$ nicotine를 첨가한 TCM-199 배양액에서 44시간 배양했을 때 체외성숙율은 각각 $44.0{\pm}4.5%,\;24.0{\pm}4.2%,\;18.0{\pm}4.9%,\;8.0{\pm}2.2%,\;0.0{\pm}0.0%$로서 대조군$(52.0{\pm}4.5%)$에 비해 낮은 체외성숙율을 나타냈다. 난자를 0.5 nM BPA와 2.5 mM nicotine을 첨가한 TCM-199에서 $40{\sim}52$시간 배양했을 때 체외성숙율은 $8.3{\pm}2.1%{\sim}26.0{\pm}3.9%$ 및 $11.2{\pm}2.2%{\sim}28.6{\pm}3.9%$로서, 44시간 배양이 다른 배양시간보다 가장 높은 체외성숙율을 나타냈다.