• Journal of the Korean Society of Groundwater Environment
• /
• v.5 no.4
• /
• pp.223-232
• /
• 1998

The Okmyong Waste Landfill which is one of major industrial waste landfills in Korea has been used for 10 years since January, 1988. The groundwater in range of 2∼3 km from the landfill is a little acidic and has high concentrations of EC, NO$_3$, and SO$_4$ because of acidic rain in Pohang. The groundwater pattern in Piper's trilinear diagram belongs to Ca-SO$_4$and Na-SO$_4$types, but Ca-SO$_4$type is more predominant. The groundwater of five monitoring wells at the landfill area is a litle alkaline and has high concentrations of TS, COD, Na, Cl, SO$_4$, Alkalinity and F because of the effect of the leachates. They also have high heavy metals of Mn, Zn, Pb, Cr and Ni but toxic organic compounds are not detected. Their groundwater pattern is Na-SO$_4$type and distinguished from the groundwater pattern Na-Cl types of the Nanjido and the Seokdae Municipal Waste Landfills. The range of groundwater contamination which is validated up to now is about 120m west from the entrance of the Okmyong Waste Landfill. To prevent the dispersion of the leachates to the outside, cutoff walls should be constructed at the boundary of the landfill. Several pumping wells should also be developed at the landfill so that the contaminated groundwater can be pumped and treated at a leachate-treatment plant in the landfill.

• Korean Journal of Crystallography
• /
• v.13 no.1
• /
• pp.25-30
• /
• 2002

The M/sub 1-x/Na/sub 2x/Al₂(BO₃)₂O (M = Ca and Sr) solid solution systems have been shown interstitial solid solutions and continuous substitutional solid solutions. The symmetry around the Eu site of yEu/sup 3+/ : M/sub 1-x/Na/sub 2x/Al/sub 2-y/Mg/sub /(BO₃)₂O (M = Ca and Sr) changes the intensities and the chromaticities of transitions. The Eu/sup 3+/ion can be very bright and efficient and have the desired emission wave-length depending on the site symmetry of the Eu/sup 3+/ion site. As the amount of Na in the Eu/sup 3+/ion doped Ca/sub 1-x/Na/sub 2x/Al₂(BO₃)₂O system increases, the Eu site symmetry is going to be a noncentrosymmetric site. With increasing x, the decreased intensity in the /sup 5/D/sub 0/→/sup 7/F₁(590 nm) transition relates to the low symmetry of the Eus/up 3+/-doped Ca/sub 1-x/Na/sub 2x/Al₂(BO₃)₂O system, because of the Ca-centered octahedron in the CaAl₂(BO₃)₂O compound. The SrAl₂(BO₃)₂O compound also provides an improved chromaticity due to the lower site symmetry of Eu/sup 3+/ion.

• Applied Microscopy
• /
• v.19 no.2
• /
• pp.119-137
• /
• 1989

It has been shown in this and earlier investigation that the turtle bladder mucosa has three main cell types on their mucosal surface. They are the granular cells, ${\alpha}$ CA cells, and ${\beta}$ CA cells. The three major transport mechanisms that occurs in the turtle bladder are sodium reabsorption, proton secretion, and bicarbonate secretion. In the present work the trans-port mechanisms by bladder epithelial cells of freshwater turtle, Pseudemys scripta, are summarized as follows. 1. The granular cells play an important role in sodium transport, while the ${\alpha}$ and ${\beta}$ CA cells do not appear to play a determining role in sodium transport. 2. It appears that the active sodium transport in the granular cells occurs in two-step process, implying that first, sodium diffuses into the cells, followed by an energy-dependent efflux step, which is catalyzed by the ouabain-sensitive Na-K ATPase. 3. The ${\alpha}$ type of CA cells are responsible for the proton secretion using the proton pump on the apical plasma membrane, while the ${\beta}$ type of CA cells are believed to be responsible for bicarbonate secretion. 4. When looked at under freeze-fracture electron microscopy, the apical plasma membrane of ${\alpha}$ cells have a characteristic population of rod-shaped intramembranous particles which are believed to be components of the proton pumps. Conversely, ${\beta}$ type of CA cells show rod-shaped particles in their basolateral plasma membranes, which is consistent with the proton absorptive, bicarbonate secretory mechanism. 5. In the turtle bladder, the ${\alpha}$ and ${\beta}$ type of cells are believed to be both responsible for proton transport, but in opposite directions.

• Journal of the Mineralogical Society of Korea
• /
• v.17 no.1
• /
• pp.61-73
• /
• 2004

The purposes of this study are to investigate the occurrence, the hydrochemical characteristics and the origin of the $CO_2$-rich springs from the Kangwon Province, and to reanalyze the previous studied results of other researchers. The $CO_2$-rich water samples were collected at 13 locations in the Kangwon Province. The $CO_2$-rich water shows a high $CO_2$ concentration ($P_{CO2}$ 0.787 to 4.78 atm), weak acidic pHs, electrical conductivity values ranging from 422 to 2,280 $\mu$S/cm, and high Fe and F contents. The chemical compositions of $CO_2$-rich water from this study area are classified into three types; $Ca-HCO_3$, Ca(Na)-$HCO_3$, $Na-HCO_3$ types. The chemical data of $CO_2$-rich waters and their host rocks indicate that $Na-HCO_3$ type water are mainly influenced by biotite, K-feldspar granite, and Ca(Na)-HC $O_3$, type water is chiefly influenced by gneiss and carbonate minerals in granite. F and Fe contents of $CO_2$-rich waters are abundant in $Na-HCO_3$, and $Ca-HCO_3$ types, respectively. The results of this study suggest that the chemical composition $CO_2$-rich water is mainly controlled by the mineralogical composition of aquifer host rocks. Oxygen and deuterium isotope data indicate that $CO_2$-rich water is meteoric origin. The $\delta^{13}$C values (-0.3$\textperthousand$ to -6.2$\textperthousand$ PDB) suggest that dissolved carbonates are mainly derived from a deep-seated $CO_2$ and partly from carbonate minerals.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.17 no.2
• /
• pp.85-94
• /
• 1988

This experiment was carried out to obtain the basic data for removal the astringency and off-flavor in soybean milk, by means of soaking of soybean in NaOH and $NaHCO_3$ solutions. The changes of phenolic compounds in soybean during soaking were investigated with HPLC and also the changes of flavor and sensority of soybean milk, prepared from soaked soybean were studied. Phenolic compounds of soybean were identified as chlorogenic, p-hydroxybenzoic, p-coumaric, ferulic and gentisic acid and, chlorogenic acid content was greater than the others. The chlorogenic acid of soybean was mainly neutral type and the other compounds were almost acidic type. Up to 85% of the chlorogenic acid was removed by soaking of soybean in 0.1% of NaOH solution for 8 hrs. Phenolic compounds of soybean was almost removed by soaking in 0.1% of NaOH solution at $90^{\circ}C$ for 1 hr. Chemical composition of soybean milks prepared from soaking of soybean in water, 0.1% NaOH and 0.5% $NaHCO_3$ solution were similar. Hexanol content of beany flavor in soybean milk was increased by soaking of soybean in NaOH solution, where as hexanal, propanal, pentanal contents were removed up to 60%. Color of soybean prepared from soaking of soybean in NaOH solution at high temperature were deep yellow but were high whiteness in soybean milk prepared from soaking of soybean in water at low temperature. Sensority of soybean milk prepared from soaking of soybean in 0.1% of NaOH solution at $90^{\circ}C$ for 1 hr was more favorable than the others.

• Economic and Environmental Geology
• /
• v.34 no.2
• /
• pp.167-173
• /
• 2001

Through alkaline hydrothermal activation processes, Na-A type zeolite was synthesized as a single phase with funnel-glass waste from a television tube factory. The autoclaving was performed in a closed teflon vessel in the range of 80~95$^{\circ}$C. The silica-rich solution as a starting material was hydrothermally synthesized with quartz in IN NaOH by heating 350uC under the pressure of 1,500 atm. $NaAlO_2$ was made from NaOH and Al(OHh by heating 95$^{\circ}$C for 2-3 hours and the molar ratios of it were $Na_2O/Al_2O_3$ = 1.4 and $H_2O/Na_2O$=8. The equi-dimensional A type zeolite (1-2 11) was formed by the simple mixing of the silica-rich solution, glass waste and $NaAlO_23$ for 1-3 hours-heating at $80^{\circ}C$. The characterization of the reaction product shows Na-A as a single phase. The synthesized zeolite has cuba-dodecahedral form and $Ca^{2+}$ ion exchange capacity of the Na-A was in the range of 215-220 mequiva1entilOO g.

• Journal of Korean Society of Environmental Engineers
• /
• v.28 no.7
• /
• pp.704-712
• /
• 2006

This research was designed to investigate the removal of heavy metals, such as $Al^{3+}$, $Cu^{2+}$, $Mn^{2+}$, $Pb^{2+}$ and $Zn^{2+}$, by adsorption on clay minerals. Bentonite(Raw-Bentonite), $Ca^{2+}$ and $Na^+$ ion exchanged bentonite(Ca- and Na-Bentonite) and montmorillonite, such as KSF and K10 from Sigma Aldrich, were used as adsorbents. The component of five inorganic adsorbents was analyzed by XRF, and the concentration of metal ions was measured by ICP. The cation exchange capacity(CEC) and the particle charge of adsorbents were measured. The initial concentration range of metal ions was $10{\sim}100$ mg/L. From the experimental results, it was shown that the adsorption equilibrium was attained after $1{\sim}2$ hours. The maximum percentage removal of $Al^{3+}$, $Cu^{2+}$, $Pb^{2+}$ and $Zn^{2+}$ on Na-Bentonite were more than 98% and that of $Mn^{2+}$ was 66%. $Al^{3+}$ was leached out from KSF with the higher concentration of hydrogen ion. Percentage removals of $Pb^{2+}$ and $Zn^{2+}$ on KSF were 88% and 59%, respectively. In general, the percentage removal of metal ions was decreased with the higher initial concentration of metal ions. The adsorption capacity of metal ions on Na-Bentonite was $1.3{\sim}19$ mg/g. Freundlich equation was used to fit the acquired experimental data. As the results, the adsorption capacity of metal ions was in the order of Na-Bentonite$\gg$Raw-Bentonite$\cong$K10>Ca-Bentonite>KSF. Freundlich constant, K of Na-Bentonite was the largest for metal ions. The order K of Na-Bentonite was Al>Cu>Pb>Zn>Mn, and the adsorption intensity(1/n) was determined to be $0.2{\sim}0.39$.

• Proceedings of the Materials Research Society of Korea Conference
• /
• 2003.03a
• /
• pp.226-226
• /
• 2003

일반적으로, 고분자 매트릭스에 층상 점토광물이 분산되어 얻어지는 복합재료는 세가지 형태를 이룬다. 첫째 통상의 복합재료는 고분자 매트릭스 내에 점토입자가 고루게 분산된 상태를 말하며, 둘째 점토 층 사이에 고분자 모노머나 올리고머가 일부분 삽입된 삽입형 복합재료(intercalated composite)이며, 셋째 점토 층 사이에 삽입된 모노머나 올리고머의 경화 또는 중합반응을 통해 점토내의 한층 한층 균일하게 매트릭스 내에 분산된 박리형 나노복합소재(exfoliated nanocomposite) 이다. 이들 복합재료들 중 박리형 나노복합소재는 적은 양의 점토가 단위 층으로 고분자 매트릭스에 완전히 분산되어 다양한 물성의 향상이 기대되는 재료이다. 따라서 최근 고분자의 기계적 강도, 팽윤 저항성 그리고 차폐특성 둥 전반적인 물성을 향상시키는 방법으로 층상 점토광물의 층 사이에 다양한 유기물을 삽입하여 층간거리를 확장시킨 유기 점토광물을 제조하고 이를 고분자 소재에 첨가하여 박리형 나노복합소재를 제조하는 방법이 많은 연구가 수행되고 있다.

• 한국디지털정책학회:학술대회논문집
• /
• 2005.11a
• /
• pp.221-229
• /
• 2005

네트워크 연결형 가상화스토리지 기술의 대표로서 SAN(Storage Area Network)와 NAS(Network Attached Storage) 및 IP SAN이 있다. NAS와 SAN은 시스템 통합, 빠르고 편리한 설치, 중앙 관리, 편리한 백업, 고가용성, 데이터 공유의 장점을 가지고 있다. 현재까지는 SAN 제품들 간 호환성 문제나 투자비용의 문제 등으로 인하여 시장 형성이 빠르지 못하나 SAN 환경에 대한 투자가 증가하고 있다. 그리고 앞으로는 서버 종속적인 가상화스토리지 시스템의 증가세는 둔화되고 NAS 또는 SAN의 가상화스토리지의 성장세가 지속될 것이다. 본 연구에서는 최근의 인터넷 환경으로 인한 컴퓨팅 환경의 변화에 따른 가상화스토리지 시스템에 대한 요구 사항의 분석과 이를 만족하기 위한 스토리지 기술과 네트워크 연결형 가상화스토리지 기술의 NAS와 SAN을 비교하며 네트워크 연결형 가상화스토리지 시스템에 관련된 표준화에 대하여 연구하였다.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.12 no.6
• /
• pp.329-334
• /
• 2002

The $CaTio_3$powder with perovskite structure was synthesized by mixing anatase $TiO_2$and $Ca(OH)_2$powders as starting materials, and KOH or NaOH as mineralizer, followed by hydrothermal method. The change of crystal structure, particle shape and size of the synthesized $CaTiO_3$powder was investigated with kind and concentration of mineralizer. It was found that the spherical particles of 0.7 $\mu$m were obtained when using 1N KOH and the hexahedrons particles of 3$\mu$m were obtained for the case of using 10 N KOH. With increasing KOH concentration, the particle shape was changed from sphere to hexahedrons and its size also increased. When using 1 N NaOH, the powder was consisted of 0.5~1 $\mu$m particle in size, whereas hexahedrons of 1~4 $\mu$m and whiskers more than 10$\mu$m in size was obtained for the 10 N NaOH solution. With increasing NaOH concentration, the particle shape was varied from hexahedrons to whiskers, showing the similar result with the KOH case. It was confirmed from EDS analysis that Na element, which was detected in hexahedrones was not contained in the whiskers.