• Title/Summary/Keyword: 약산

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Analysis of mine tailings, field soils, and paddy soils around Jingok abandoned mine (진곡광산 광미와 주변 토양의 오염조사)

  • 김선태;윤양희;박제안;심의섭
    • Journal of Korea Soil Environment Society
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    • v.4 no.2
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    • pp.175-183
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    • 1999
  • Mine tailings, field soils, and paddy soils around Jingok abandoned mine were analyzed In order to investigate their pollution levels of heavy metals and cyanide. The average contents of As, Cd, Cu. Hg. Pb, Zn, and CN ̄in mine tailings were 3.94$\times$$10^3$, 14.3, 266, 6.13, 4.07$\times$$10^3$, 2.51$\times$$10^3$, and 1.19mg/kg, respectively. The pollution indices calculated by the tolerance level of Kloke were 32~58 and the pH values were slightly acidic in mine tailings. In the field and paddy soils of Jingok abandoned mine area except for soils nearby mine tailings, concentrations of the heavy metals were less than standards of soil pollution of agricultural area in the environmental protection law.

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Formulation of omeprazole using omeprazole-ethylenediamine complex of omeprazole for its stabilization

  • Rhee, Gye-Ju;Hwang, Sung-Joo;Oh, Sea-Jong;Park, Seong-Bae;Park, Sun-Hee;Woo, Jong-Soo;Lee, Chang-Hyun
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 1995.04a
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    • pp.132-132
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    • 1995
  • OMPED의 결합비는 1:1 몰비로 복합체가 형성됨을 확인하였다. 수용액중(pH 7.0)에서 OMP는 분해속도 k=1.542$\times$$10^{-2}$$hr^{-1}$, shelf life=6.81hr 이었고 OMPED는 k=2.088$\times$$10^{-4}$$hr^{-1}$, shelf life=502.8hr이며 중성은 물론 약산성에서 안정하였다. HPMCP로 장용피한 OMPED pellet은 산저항성이 완벽하고 용출속도가 양호하였으며, OMPED 정제에서는 CAP로 코팅한 정제가 가장 큰 AUC값을 나타내었다. Witepsol H-15 기제를 사용한 각 좌제의 생체이용율은 OMPED 좌제가 86.53 $\mu\textrm{g}$ㆍmin/$m\ell$ 로서 OMP 좌제 61.9 $\mu\textrm{g}$ㆍmin/$m\ell$ 및 OMP-$\beta$-CD 좌제 68.8 $\mu\textrm{g}$ㆍmin/$m\ell$이다.

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Study on the Stability and Fate of Vicine and Convicine in Fababean (Fababean 중의 Vicine과 Convicine의 안정성에 관한 연구)

  • 박신인
    • Journal of Food Hygiene and Safety
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    • v.8 no.2
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    • pp.85-90
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    • 1993
  • The aglycones of vicine and convicine have been implicated as the causative factors for favism in fababeans. Thus, the presence of these compounds in fababeans is a potential obstacle to the use of fababeans and fababean preparations in foods. Investigations of vicine stability in fababeans and in pure solutions revealed that vicine is very stable, however, divicine derived from vicine by ${\beta}-gIucosidase$ action or by acid hydrolysis is highly unstable at conditions prevalent in food processing. Therefore, the possibility of incorporating of ${\beta}-gIucosidase$ in food products containing fababean preparations was suggested to overcome potential risks of favism related to the consumption of fababean fortified products.

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Optimal Condition of Mycelial Growth of Grifola frondosa (잎새버섯 균주의 균사체 생육 최적조건)

  • Chi, Jeong-Hyun;Kim, Jeong-Han;Won, Sun-Yee;Seo, Geon-Sik;Ju, Young-Cheoul
    • The Korean Journal of Mycology
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    • v.35 no.2
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    • pp.76-80
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    • 2007
  • This study was carried out to obtain basic data on mycelial growth characteristics for an artificial cultivation of Grifola frondosa. Ten strains of G. frondosa were collected from Korea, China and Japan and investigated its optimal culture condition. Among four kinds of mushroom culture media, PDA medium was selected as the suitable culture medium. The optimal conditions for the mycelial growth of G. frondosa in PDA medium were $25^{\circ}C$ and $4{\sim}5$ of pH, respectively. The carbon and nitrogen sources for the optimum mycelial growth were fructose and peptone, respectively, and the highest mycelial growth was observed when the C/N ratio was $10{\sim}20$.

Effects of the Moisture on the Overall Heat Transfer Through Heat Insulators Opaque Envelopes (불투명 외피의 열관류에서 단열재의 습도영향)

  • Lee, S.
    • Solar Energy
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    • v.18 no.3
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    • pp.63-69
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    • 1998
  • The heat conduction and the water vapour diffusion flow through heat insulators between hygroscopical moist building materials were measured by means of the plate method. It was found that the heat transport increases with a moisture motion occuring in the temperature drop. On his basis of simplified assumptions, the increase in the thermal conductivity was calculated from the rate of diffusion flow per unit area, which generally resulted in values inferior to the measured values. The Increase in the heat transport due to water vapour diffusion measured at a large-scale wall specimen was inferior to the one measured by means of the plate method by using a comparable arrangement of layers. The overall heat transfer caused by moisture motion is not a characteristic value of the material, but a property of the whole wall structure

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Transformation of Irregular Waves in Shallow Water (천해에서 불규칙파의 변이)

  • 유동훈
    • Journal of Korean Society of Coastal and Ocean Engineers
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    • v.5 no.3
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    • pp.212-220
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    • 1993
  • A numerical model for the transformation of irregular waves in a coastal area is developed, which takes account of shoaling, refraction, diffraction, bottom friction and wave breaking. The governing equations are the usual energy conservation equation and kinematic conservation equations, but to consider the diffraction effects additional terms are included in the usual kinematic conservation or wave number equations. A linear superposition technique is used to represent the spectral formation. and an explicit formula is developed for the estimation of friction factor of irregular waves. A breaking criterion of component waves, which is the modified form of the Kitaigorodskii saturation relation, is employed to restrict the growth of shoaling waves in very shallow waters. The model was applied to a laboratory test and satisfactory agreement was obtained between the computation and measurement.

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A study on chemical vapor deposition process for the proparation of thin SiC films (실리콘 카바이드 박막 제조를 위한 증착 반응연구)

  • 고준호;우성일
    • Electrical & Electronic Materials
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    • v.4 no.4
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    • pp.344-353
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    • 1991
  • 무정형 SiC 박막을 수평형 CVD반응기로부터 SiH$_{4}$ 및 H$_{2}$를 반응기체로 하여 실리콘 웨이퍼위에 증착시켜 제조하였다. 박막 성장 속도는 상압에서 650.deg.C와 850.deg.C범위에서 측정되었다. 반응기체의 유량은 1000sccm으로 고정하였으며 SiH$_{4}$와 CH$_{4}$의 유량을 변화시켰다. 증착 반응속도식으로 표면 반응이 율속단계인 Eley-Rideal 모델과 SiH$_{4}$와 CH$_{4}$의 종도에 m차로 비례하는 두가지 속도식을 가정하였다. 증착시간에 따른 SiC 박막두께의 측정으로부터 얻은 증착 반응 속도로부터 회귀 분석법에 의하여 두가지 반응속도식의 반응속도 상수를 구하였다. 얻어진 반응속도식에 의해서 계산된 값과 실험치를 비교한 결과 0.15차의 반응속도식이 Eley-Rideal반응기구보다 약산 더 잘 맞음을 알 수 있으나 두 모델 다 약간씩 실험결과와 차이가 나고 있다. 이것은 본 실험의 증착 조건의 율속단계가 확산 단계와 표면 반응 단계의 전이영역 즉 본 실험의 증착조건에서 확산속도와 표면 반응속도가 비슷하기 때문으로 생각된다. 또한 Eley-Rideal 반응기구에서 부터 얻어진 SiH$_{4}$ 및 CH$_{4}$의 흡착평형상수 $K_{s}$$K_{c}$ 값을 비교하면 1000K이하에서는 $K_{s}$$K_{c}$ 보다 큰 값을 가지는데 이것은 Gibbs 자유에너지 최소화 방법에서 구한 결과와 일치하였다.

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Strength Demand Calculation for Retrofitting Unreinforced Masonry Buildings Based on the Displacement Coefficient Method and the Preliminary Seismic Evaluation Procedure (변위계수법 및 약산식 내진성능평가에 기초한 비보강 조적조 건물의 내진보강 요구강도 산정)

  • Seol, Yun Jeong;Park, Ji-Hun;Kwak, Byeong Hun;Kim, Dae Ho
    • Journal of the Earthquake Engineering Society of Korea
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    • v.26 no.1
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    • pp.31-38
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    • 2022
  • Based on the nonlinear static analysis and the approximate seismic evaluation method adopted in "Guidelines for seismic performance evaluation for existing buildings, two methods to calculate strength demand for retrofitting individual structural walls in unreinforced masonry buildings are proposed." The displacement coefficient method to determine displacement demand from nonlinear static analysis results is used for the inverse calculation of overall strength demand required to reduce the displacement demand to a target value meeting the performance objective of the unreinforced masonry building to retrofit. A preliminary seismic evaluation method to screen out vulnerable buildings, of which detailed evaluation is necessary, is utilized to calculate overall strength demand without structural analysis based on the difference between the seismic demand and capacity. A system modification factor is introduced to the preliminary seismic evaluation method to reduce the strength demand considering inelastic deformation. The overall strength demand is distributed to the structural walls to retrofit based on the wall stiffness, including the remaining walls or otherwise. Four detached residential houses are modeled and analyzed using the nonlinear static and preliminary evaluation procedures to examine the proposed method.

Histochemical Study on the Mucous Gland of the Frog (Rana nigromaculata) Skin under Dry Conditions (건조상태가 개구리(Rana nigromaculata) 피부 점액선에 미치는 영향에 대한 조직화학적 연구)

  • Park, Joong-Suk
    • The Korean Journal of Zoology
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    • v.17 no.1
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    • pp.43-50
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    • 1974
  • This study was performed in order to know the histochemical changes of mucosubstances in mucous glands under normal and dry conditions. The frogs, Rana nigromaculata Hallowell, were collected near Seoul area in mid-August. The experimental group was retained under dry conditions for 12, 24, 30 and 36 hrs to make a comparison to normal group. The results obtained were as follows: 1. Mucosubstances in mucous glands of the frog skin contain neutral mucin and sulfated and non-sulfated mucins. Mucosubstances in the cells of the gland neck are neutral mucin, while the gland body is composed of neutral, sulfated and non-sulfated mucins. 2. Mucosubstances in mucous gland of the frog skin decreased distinctively under dry conditions, as is evident from the hitochemical properties, te neutral mucins were influenced more clearly than acid mucins. 3. Histochemical compositions of the mucosubstances in the cell of the mucous gland (the gland neck and the gland body) were not changed. 4. The phenomena were considered as a general adaptation syndrome to keep homeostasis.

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Histochemical Study on the Serous Gland of Frog(Rana nigromaculata) Skin under Dry Conditions (건조상태가 개구리(Rana nigromaculata) 피부 장액선에 미치는 영향에 대한 조직화학적 연구)

  • Park, Joong-Suk
    • The Korean Journal of Zoology
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    • v.18 no.3
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    • pp.107-114
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    • 1975
  • This study was performed in order to know the histochemical changes of mucosubstances in granular secretions of the serous gland under normal and dry conditions. The frogs were collected near Jinju and the experimental groups were retained under dry conditions for 24, 48, 72 and 96 hours to make a comparison with normal group. The results obtained were as follows: 1. The secreting granules in serous gland of the frog skin contained neutral and weakly acidic mucosubstances. 2. the secreting granules in serous gland of the frog skin were significantly decreased under dry conditions, as is evident from the histochemical properties. The neutral mucosubstances were decreased more than acidic mucosubstances. 3. Histochemical compositions of the mucosubstances of secreting granules in the lumen of the serous gland were not changed according to dry condition.

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