• 한국식품영양학회지
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• 제14권6호
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• pp.521-526
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• 2001

홍버섯쌀은 현재 혈압과 혈중 고지혈 강하제로서 의약품 뿐만 아니라 기능성 식품으로서 많은 관심을 불러일으키고 있다. 그러나 이 홍버섯에 함유된 유효성분인 monacolin K의 정성법과 정량적인 분석 방법이 제시되지 못하였다. 본 연구에서는 monacolin K의 lactone과 acid 형태에 대한 각각의 정확한 정성법과 정량가능한 분석법을 제안하였다. 이 방법은 HPLC의 역상컬럼을 사용하여 acetonitrile과 0.1%TFA를 62:38의 비율로 혼합한 용매를 사용하는 것이다. 이 제시된 방법을 활용했을 때 홍국중의 monacolin K의 최소 검출농도는 5ng이었다.

• 한국응용과학기술학회지
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• 제22권3호
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• pp.204-211
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• 2005

The structure of nitrogen adsorption complex of fully dehydrated $Cd^{2+}$ ion exchanged zeolite-X, $|Cd_{46}(N)_{18}|[Si_{100}Al_{92}O_{384}]$, was determined in the cubic space group $Fd\overline{3}$ at 21(1) $^{\circ}C$ [a = 24.863(4) ] by single crystal X-ray diffraction analysis. The crystal was prepared by ion exchange in a flowing steam of 0.05 M aqueous solution $Cd(NO_3)_2$ : $Cd(O_2CCH_3)_2$ = 1:1 for five days, followed by dehydration at $500^{\circ}C$ and $2{\times}10^{-6}$ Tor. for two days, and exposured to 100 Tor. zeolitically dry nitrogen gas at 21(1) $^{\circ}C$. The structure was determined in atmosphere, and was refined within $F_0$ > $4{\sigma}(F_0)$ using reflection for which the final error can appear in indices $R_1$ = 0.097 and $wR_2$ = 0.150. In this structure, $Cd^{2+}$ ions occupied four crystallographic sites. Nine $Cd^{2+}$ ions filled the octahedral site I at the centers of hexagonal prisms (Cd-O = 2.452(16) ${\AA}$). Eight $Cd^{2+}$ ions filled site I' (Cd-O = 2.324(19) ${\AA}$). The remaining 29 $Cd^{2+}$ ions are found at two nonequivalent sites II (in the supercages) with occupancy of 11 and 18 ions. Each of these $Cd^{2+}$ ions coordinated to three framework oxygens, either at 2.159(15) or 2.147(14) ${\AA}$, respectively. Eighteen nitrogen molecules were adsorbed per unit cell and three per supercage.

• Journal of the korean society of oceanography
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• 제39권1호
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• pp.46-56
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• 2004

Spectral attenuation of light and upwelling radiance were measured in the western coast of Korea on board the R/V Inchon 888 of the Korean National Fisheries Research and Development Institute(NFRDI) during four seasons. The goal of these efforts was to determine the spatial and temporal distribution of the inherent and apparent optical properties of the water, and the factors that control their distribution. Our data indicate that while stratification of the water column, phytoplankton, and wind stress determined the vertical distribution of the optical parameters offshore, it was the tidal current and sediment type that controlled both the vertical and horizontal distribution in the coastal areas. These findings led to the development of a model that estimates the spectral attenuation of light with respect to depth and time for the Yellow Sea. The model integrates water leaving radiance from satellites, sediment types, current vectors, sigma-t, bathymetry, and in situ optical measurements in a learning algorithm capable of extracting optical properties with only knowledge of the environmental conditions of the Yellow Sea. The performance of the model decreases with increase in depth. The mean absolute percentage error (MAPE) of the model is 2% for the upper five meters, 8-10% between 6 and 50 meters, and 15% below 51 meters.

• 한국진공학회지
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• 제6권4호
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• pp.308-313
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• 1997

Capacitance Diaphragm Gauge(CDG)를 전달표준기로 사용하여 한국과 영국의 저진 공표준의 국제비교를 수행한 결과 양국 표준기에서 교정한 CDG의 압력비의 차이는 0.05% 이었다. 또한 두 개의 Spinning Rotor Gauge(SRG)를 이용하여 한국과 일본이 고진공표준의 국제비교를 수행한 결과 양국 표준기에서 교정한 SRG의 accommodation coefficient($sigma$)의 차이가 0.4% 이내이었다. CDG와 SRG를 이용한 한국과 영국의 저진공표준기 및 한국과 일 본의 고진공표준기의 국제비교 결과 CDG 및 SRG 자체의 고유오차범위 이내에서 결과가 일치함을 확인할 수 있었다.

• 자원환경지질
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• 제27권3호
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• pp.219-229
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• 1994

The Sangra Pb-Zn deposit is located in the Gampo area. Most Cretaceous sedimentary rocks and Paleogene felsic intrusives in the study area have experienced intense propylitization. Such propylitization and Pb-Zn mineralization in ore veins are involved with the fluid having very low oxygen isotopic composition.Sulfurisotopic equilibrium temperature during the main Pb-Zn mineralization (late stage I) is calculated as $T=275^{\circ}{\sim}295^{\circ}C$. Oxygen and sulfur fugacity in late stage I fluid is estimated as $logfO_2=-34.4{\sim}-29.1$ and $logfS_2=-12.0{\sim}-8.2$ bars. It is inferred that the sulfur isotopic composition oflate stage I fluid was very high such as ${\delta}^{34}S_{{\Sigma}S}=+22.4{\sim}+22.5$‰ and the origin of sulfur was ocean water sulfate. Oxygen and hydrogen isotopic composition of water in ore-forming fluid was gradually increased and more abundantly affected by ocean water from early to late mineralization stage as follows; (late stage I) ${\delta}^{18}O_{H2O}=-7.2{\sim}-1.1$‰, ${\delta}D_{H2O}=-87{\sim}-84$‰, (stage II) ${\delta}^{18}O_{H2O}=-2.4{\sim}-0.8$‰, ${\delta}D_{H2O}=-39{\sim}-21$‰ (stage III) ${\delta}^{18}O_{H2O}=+0.7{\sim}+12.6$‰, ${\delta}D_{H_2O}=-49{\sim}-42$‰. The pH in ore-forming fluid was about 4.7 during late stage I and is thought to have been gradually decreased from late stage I to stage II mineralization.

• 대한약침학회지
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• 제12권4호
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• pp.33-50
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• 2009

Objectives : This study was conducted to confirm validation and stability of concentration analysis method of pure melittin (Sweet Bee Venom-Sweet BV) extracted from the bee venom by utilizing protein isolation method of gel filtration. Methods : All experiments were conducted at Biotoxtech, a non-clinical studies authorized institution, under the regulations of Good Laboratory Practice (GLP). Standard solutions of melittin (SIGMA, USA) and test substances were dispensed and were analyzed with HPLC for Sweet BV to secure the validation of analysis. Results : 1. Measurement of system suitability of Sweet BV satisfied criterion of below 3%. 2. Confirming Linearity of Sweet BV in 10-200${\mu}g/m\ell$ solution yielded correlation coefficient (r) of 0.995 and accuracy of 85-115% which satisfy criterion. 3. Measurement of Specificity of Sweet BV didn't yield any substance affecting the peak of test substances, but detected at 21.22min verified as the test substance. 4. Confirming Intra-day of Sweet BV, accuracy and precision of 0.1, 100${\mu}g/m\ell$ were 105.70, 95.81 and 0.66, 0.73, respectively, satisfying both criteria of accuracy (85-115%) and precision (within 10%). 5. To measure Stability in autosampler, all samples used in Intra-day reproducibility sat in the autosampler for five hours and were re-analyzed. Both variability and precision satisfied the criteria. 6. Homogeneity of Sweet BV (0.1, 100${\mu}g/m\ell$) at upper, middle, and lower layers all satisfied the accuracy and precision criteria. 7. Stability of Sweet BV (0.1, 100${\mu}g/m\ell$) at room temperature for four hours and refrigerated for 7 days all satisfied the criterion. 8. For the measurement of Quality control, QC samples measured on the first and eighth day all satisfied accuracy and precision criteria. Conclusion : Above experiment data satisfies validation and stability of concentration analysis method of Sweet BV.

• Asian-Australasian Journal of Animal Sciences
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• 제20권6호
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• pp.971-975
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• 2007

Two experiments were conducted to evaluate the feeding values of red pepper seed oil meal (RPSOM) and to investigate its dietary supplementation on broiler performances. In Exp. 1, nutritional values of RPSOM were evaluated by analyzing chemical composition and determining true metabolizable energy (TME), nitrogen corrected TME (TMEn) and true available amino acid (TAAA). RPSOM contained 22.50% of CP, 4.75% of ether extract, 27.70% of crude fiber, 4.73% of crude ash and 49.97 ppm of xanthophylls. The contents of capsaicin and dihydrocapsaicin were 34 mg and 31 mg/100 g DM, respectively. The values of TME and TMEn determined by force-feeding 16 roosters were 1.73 kcal/g and 1.63 kcal/g DM, respectively. The average TAAA value of 17 amino acids was 85.22%. In Exp. 2, a total of 225 Ross male broiler chicks, 3 weeks old, were randomly divided into 9 groups of 25 birds each and assigned to three experimental diets containing 0 (control), 5 or 10% RPSOM fed ad libitum for 3 weeks. No significant differences were observed in growth performances and carcass characteristics. The level of serum cholesterol in the 10% RPSOM group was significantly lower than that of the control group (113.92 vs. 137.50 mg/dl). The dietary RPSOM at 5 and 10% levels increased the content of C18:2 ${\omega}{\sigma}$ in leg muscle compared with the control group. The results suggested that RPSOM can be included into broiler feed up to 10% without any negative effects on broiler performances and physiological responses and used as a non-conventional plant protein source, if its nutritional values are well evaluated.

• 한국수산과학회지
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• 제28권4호
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• pp.397-400
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• 1995

Chitosan 용액의 물성학적 특성을 조사하기 위하여 chitosan 용액의 점도에 미치는 전단속도, 온도, 농도 및 염의 영향을 조사한 결과, chitosan 용액$(0.5\%)$의 유동곡선은 hysteresis loop가 나타나는 Bingham 유체와 일치하였고, $10^{\circ}C-40^{\circ}C$에서 Arrhenius 온도의존성을 나타내었다$(2\%,\;2.5\%,\;3\%\;chitosan$ 용액). 활성화 에너지는 3.25-8.35(kcal/g mol)로 전단속도가 높을수록 그리고 농도가 높을수록 증가하였다. Chitosan 용액의 겉보기점도는 농도가 증가할수록 지수적으로 증가하였고, 측정 온도가 높을수록 농도의존성은 낮았다. 한편 chitosan용액에 염을 첨가하였을 때 점도감소현상이 나타났으며, 염농도가 높아짐에 따라 점도의 감소폭은 줄어들었다 염의 종류에 따른 점도변화는 없었다

• KIEE International Transactions on Electrophysics and Applications
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• 제4C권1호
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• pp.21-25
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• 2004

From the gradual increasing state of charge (GISOC) observations, electrochemical behavior of multi-walled carbon nanotube│(lM LiP $F_{6}$ , EC,DEC,DME 3:5:5 volume ratio)│lithium cells was evaluated using the galvanostatic charge-discharge process. A MWCNT delivers a specific charge capacity of 1,300 mAh/g in a Li cell when cycled up to an end voltage of 0 V (vs. Li/L $i^{＋}$ )at a constant current rate every 10 hours. However, in the present study, the specific discharge capacity obtained is 338 mAh/g, thus amounting to a coulombic efficiency of only 26％. Further, when the MWCNT│Li cells were tested using the GISOC method, two distinguishable linear-fit ranges were observed due to the intercalation/deintercalation of lithium, which were found to have II $E_1$, IIC $s_1$ and II $E_2$of 27.3％, 372 mAh/g, and 25.5％, respectively. Q $c_1$, could be calculated from the data of IIE and IICs of each range by the modified equation "II $C_{sum}$= $\Sigma$( $Q_{C}$- $Q_{D}$)=(II $E_{1}$$^{-1}$ ) $Q_{Dl}$ ＋(II $E_2$$^{-1}$ -1) ( $Q_{D2}$- $Q_{Dl}$ ) ＋ IIC $s_1$= $Q_{Cl}$ - $Q_{Dl}$ ". Results of the GISOC method could be converted to the results of galvanostatic charge-discharge process, irrespective of the state of charge of the cell or battery.ery.y.y.

• 대한조선학회논문집
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• 제43권4호
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• pp.422-430
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• 2006

The horn and movable parts around the gap of the conventional semi-spade rudder are visualized by high speed CCD camera with the frame rate of 4000 fps (frame per second) to study the unsteady cavity pattern on the rudder surface and gap. In addition, the pressure measurements are conducted on the rudder surface and inside the gap to find out the characteristics of the flow behavior. The rudder without propeller wake is tested at the range of $1.0{\leq}{\sigma}_v\;1.6$ and at the rudder deflection angle of $-8{\leq}{\theta}{\leq}10^{\circ}$. The time resolved cavity images are captured and show strong cavitation around the rudder gap in all deflection angles. As the deflection angle gets larger, the flow separated from the horn surface increases the strength of cavitation. The accelerated flow along the horn decreases its pressure and the separated flow from the horn increases the pressure abruptly. The pressure distribution inside the gap reveals the flow moving from the pressure to suction side. In the negative deflection angle, the turning area on the movable part initiates the flow separation and cavitation on it.