• Journal of the Korean Applied Science and Technology
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• v.25 no.2
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• pp.205-210
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• 2008

The transformation of the liquid crystal complex made by binding of anionic surfactant, sodium dodecyl sulfate (SDS), into high charge density cationic polymer, the homopolymer of diallyldimethylammonium chloride (PDADMAC) was induced by adding of nonionic surfactants and investigated by means of microscopy and FE.SEM. Among nonionic surfactants in this experiments polyethylene glycol (3 mol) ether of lauryl alcohol (laureth-3) made variation in the complex. The laureth-3 transformed the complex into spherulite vesicle with the size of ca.$100{\mu}m$. This change increased the viscosity and the turbidity of the solution phase separated originally. Microscope showed that they are spherulite particles and polarized microscope suggested they are multi.lamellar liquid crystals. FE-SEM also proved that explicitly.

• Journal of the Korean Society for Nondestructive Testing
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• v.23 no.5
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• pp.520-525
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• 2003

Fast Breeder Test Reactor (FBTR) is a 40MW (thermal) / 13.2MW (electrical), Plutonium - Uranium mixed carbide fuelled, sodium cooled, loop type nuclear reactor operating at Indira Gandhi Centre for Atomic Research (IGCAR), Kalpakkam. Its main aim is to generate experience in operation of fast reactors and sodium systems and to serve as an irradiation facility for development of fuels and structural materials fur fast reactors. Nuclear reactors pose difficulties to the NDT techniques used to monitor the conditions of the internal components. Sodium cooled fast breeder reactors have their own typical difficulties in using the NDT techniques. These are due to the need for operation in aggressive environment of nuclear radiation and sodium (molten/vapour), as well as the need to maintain leak tightness of a very high order during all states of reactor operation and shutdown for fuel handling, maintenance and remote inspection. This paper discusses the following NDT techniques, which have been successfully used for the past 15 years in FBTR: (i) Periscope and Projector, (ii) Core Co-ordinate Measuring Device and, (iii) Optical fiberscope. The inspection using these techniques have given confidence for further reactor operation at high power by giving useful data on the conditions of the components inside the reactor vessel.

• Neonatal Medicine
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• v.25 no.3
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• pp.131-135
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• 2018

Hyponatremia is defined as a plasma sodium concentration of <135 mEq/L. It is a common electrolyte imbalance in newborns. We report the case of a term neonate with cleft lip, cleft palate, imperforate anus, normal male karyotype, and chronic hyponatremia. On the 4th day of life, he showed hyponatremia (plasma sodium concentration 130 mEq/L) with low serum osmolality (275 mOsm/kg), high urine sodium (116.7 mEq/L), and high urine osmolality (412 mOsm/kg). His thyroid and adrenal functions were normal. Despite intravenous and oral sodium supplementation and hydrocortisone treatment, hyponatremia persisted. Brain magnetic resonance imaging showed normal results. He was diagnosed as having reset osmostat, a rare subtype of the syndrome of inappropriate secretion of antidiuretic hormone characterized by a subnormal threshold for antidiuretic hormone secretion, with hypotonic hyponatremia.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.178-181
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• 2008

Cylindrical stainless-steel/sodium heat pipe for a high-temperature application was manufactured and tested for transient and steady-state operations. The container material was made of stainless-steel 316, and the working fluid was sodium. Stainless-steel 316 mesh screen was inserted as a capillary structure. The working fluid fill charge ratio was approximately 64 $\sim$ 181% based on the pore space of the wick. The outer diameter of the heat pipe was 12.7 mm and the total length was 250 mm. The evaporator part was 150 mm and the condenser 80 mm. The performance test of the heat pipe has been conducted in the furnace with up to 800 W. The variation of the average heat transfer coefficient was investigated as a function of heat flux and vapor temperature. As input thermal load increased, it was showed that difference of temperatures in evaporator and condenser decreased and that operating section and heat transfer characteristics at the heat pipe increased.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.2
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• pp.92-103
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• 1989

This study was performed in order to produce the basic data for devising irrigation project and desalinization countermeasure through analyzing salt movement and desalinzation effects. The Desalinization experiments with water management practices were carried out, using the soil samples collected in New Manguem tideland. The changes of electrical conductivity, exchangeable sodium percentage, pH and hydraulic conductivity during the desalinization experiments, and the correlations between various factors influencing desalinization, were analyzed by the statistical method. The results obtained from this study were summarized as follows: 1. The sample soils used in this study were salin-sotlic soils with the high electrical conductivity and the high exchangeable sodium percentage, and the soil texture was silt loam. 2. A large amount of the soluble salts was removed in the begining of desalinization experiments. The initial electrical conductivity and the initial exchangeable sodium percentage decreased considerably in the beginning, and were gradually slow in the rate of decrease 3. The value of pH showed a tendency to increase during the desalinization and were little by little slow in the rate of increase, and could be estimated by the regression equation. 4. The initial hydraulic conductivity were raised greatly with gypsum treatment and the penmeability was maintained adequately, The hydraulic conductivity and the leaching time elapsed during the desalinization could be estimated by the regression equation. 5. The water requirement for desalinization with various water management practices could be estimated for a given electrical conductivity, exchangeable sodium percentage, and pH reading respectively.

• Computers and Concrete
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• v.5 no.6
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• pp.573-597
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• 2008

Among artificial intelligence-based computational techniques, adaptive neuro-fuzzy inference systems (ANFIS) are particularly suitable for modelling complex systems with known input-output data sets. Such systems can be efficient in modelling non-linear, complex and ambiguous behaviour of cement-based materials undergoing single, dual or multiple damage factors of different forms (chemical, physical and structural). Due to the well-known complexity of sulfate attack on cement-based materials, the current work investigates the use of ANFIS to model the behaviour of a wide range of self-consolidating concrete (SCC) mixture designs under various high-concentration sodium sulfate exposure regimes including full immersion, wetting-drying, partial immersion, freezing-thawing, and cyclic cold-hot conditions with or without sustained flexural loading. Three ANFIS models have been developed to predict the expansion, reduction in elastic dynamic modulus, and starting time of failure of the tested SCC specimens under the various high-concentration sodium sulfate exposure regimes. A fuzzy inference system was also developed to predict the level of aggression of environmental conditions associated with very severe sodium sulfate attack based on temperature, relative humidity and degree of wetting-drying. The results show that predictions of the ANFIS and fuzzy inference systems were rational and accurate, with errors not exceeding 5%. Sensitivity analyses showed that the trends of results given by the models had good agreement with actual experimental results and with thermal, mineralogical and micro-analytical studies.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2005.05a
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• pp.267-271
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• 2005

This experiment was carried out at 450"C, which is relatively lower than the temperature for supercritical water oxidation (600-650$^{\circ}C$). In this experiment, the decomposition rates of various incombustible organic substances were very high. In addition, it was confirmed that hetero atoms existed in organic compounds and chlorine was neutralized by sodium(salt formation).However, to raise the decomposition rate, relatively large amount of sodium nitrate(3-4 times the equivalent weight) was required. When complete oxidation is intended as in the case with PCB, the amount of oxidizer and decomposition cost is important. But when vaporization reduction is required as in the case with nuclear wastes, the amount of radioactive wastes increases instead. But as can be seen in the result of XRD measurement, unreacted sodium nitrate remained unchanged. If oxidation reaction of organic substance simply depends on collision frequency, unreacted sodium nitrate can be recovered and reused, then oxidation equivalent weight would be sufficient. In the gas generated, toxic gas was not found. As the supercritical water medium has high reactivity, it is difficult to generate relatively low energy level SO$_{X}$, and NO$_{X}$.

• Magazine of the Korean Society of Agricultural Engineers
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• v.31 no.1
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• pp.96-105
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• 1989

This laboratory study was performed to produce basic data for the estimation of water requirements for desalinization, through analyzing changes of the electrical conductivity and the exchangeable sodium percentage during the desalinization of reclaimed tidelands. Desalinization experiments were carried out by two water management practices, namely, the leaching method by subsurface drainage and the rinsing method by surface drainage, using samples of silt loam soil and silty clay loam soil collected in reclaimed tidelands. The results obtained from this study were summarized as follows : 1. The sample soils used in this study were saline-sodic soils with the high electrical conductivity and the high exchangeable sodium percentage. 2. Changes of the electrical conductivity and the exchangeable sodium percentage with water requirements for desalinization showed a similar tendency in the desalinization experiment by the same water management practice. 3. The regression equation between the relative electrical conductivity(EC/EC) and water requirements for desalinization(Dw/Ds) could be described by Dw/Ds=O. 29x(EC/EC.) -0.982 (Leaching method), Dw/Ds=3. 678X0. 030(EC/EC ) (Rinsing method). 4. The regression equation between the relative exchangeable sodium percentage (ESP/ESP ) and water requirements for desalinization (Dw/Ds) could be expressed in Dw/Ds = 0.039 x (ESP/ESP. ) - 1. 134 (Leaching method), Dw/Ds=7. 197X0. 024(ESP/ESP ) (Rinsing method). 5. It was estimated that water requirements for the adequate desalinization would be Dw/Ds=0.3 (Leaching method) and Dw/Ds=3.0 (Rinsing method)

• The Korean Journal of Physiology
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• v.10 no.1
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• pp.35-40
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• 1976

In an attempt to examine the effect of ginseng on sodium transport across the biological membrane, we have studied effects of ginseng alcohol extract on the short-circuit current(SCC) and the $Na^+-K^+$-activated ATPase activity in isolated frog skin preparations. 1. Ginseng alcohol extract applied to the mucosal surface of the frog skin significantly increased SCC at low concentration($1{\sim}10mg%$) but decreased SCC at higher concentration($50{\sim}250mg%$). 2. Similarly, when the drug was added to the serosal bathing medium, the SCC was stimulated at low doses($5{\sim}25mg%$) and inhibibited at high doses($50{\sim}250mg%$). 3. $Na^+-K^+$-activated ATPase activity of the frog skin epidermal homogenate was significantly inhibited by ginseng alcohol extract, the effect being proportional to the concentration of the drug in the incubation mixture. These results may suggest that a low dose of ginseng alcohol extrat enhances the transepithelial sodium transport probably by increasing the permeability of outer membrane of the transporting cell to sodium ion, whereas a high dose of drug reduces the sodium transport primarly by inhibiting $Na^+-K^+$ ATPase mediated active transport step.

• KSBB Journal
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• v.26 no.2
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• pp.107-111
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• 2011

The essential operating parameters in virus vaccine production are multiplicity of infection (MOI), harvest time, and infection time. Stimulating agents also can be applied in order to improve vaccine productivity further. We investigated the optimum operating conditions in porcine transmissible gastroenteritis virus (TGEV) vaccine production and the applicability of sodium butyrate (NaBu) as a stimulating agents for the improvement of vaccine productivity. The optimum MOI, infection time, and harvest time for high production of TGEV by swine testicle (ST) cells were found to be 0.0001 pfu/cell, 3 day after cell inoculation, and 24 hpi, respectively. NaBu is known as a histone deacetylase inhibitor that has been widely used for the high expression of recombinant protein using mammalian cells and for the enhancement of virus propagation. So we tried to examine the potential of NaBu as a stimulating agent and to determine the optimum concentration by comparing TGEV titers with different range of NaBu concentration. TGEV titer with 5 mM NaBu was 1.5 times higher than control. Therefore, we concluded that NaBu can be a promising agent for stimulating various vaccine production including TGEV and the optimum NaBu concentration for TGEV production was determined to be 5 mM.