• The Korean Journal of Food And Nutrition
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• v.10 no.4
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• pp.439-445
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• 1997

Radish roots were salted in 4 different salt concentrations (5, 10, 15, 20%) for 3 months followed by desalting. The effects of desalting process on salt concentration, Ca content, texture and sensory characteristics were investigated during 3 days of desalting period at $25^{\circ}C$. NaCl content in danmuji salted in lower NaCl concentrations decreased rapidly and a linear relationship was found between the decrease in NaCl content and the logarithmic value of desalting time. Changes in Ca content of danmuji also exhibited a similar trend to that of NaCl content. Hardness of radish root tended to increase wit an increase in desalting time up to 2 days of desalting and then decreased slightly at the 3rd day of desalting. The results of sensory evaluation revealed that regardless of salt concentration used acidic, salty odor and taste of danmuji decreased significantly during desalting, however, there was very little change in yeast-moldy odor and taste with the intensity being very low in danmuji salted in higher salt concentrations. Among the textural properties, the crispness of danmuji salted in 5, 10 and 20% NaCl concentrations increased up to 2 days of desalting and decreased slightly thereafter, whereas that of radish salted in 15% NaCl concentration increase continously during 3 days of desalting. Total acceptibility was best in danmuji salted in 20% NaCl concentration and desalted for 3 days.

• Journal of Soil and Groundwater Environment
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• v.14 no.6
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• pp.78-86
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• 2009

Applicability of CaO and steel slag as stabilizers in the treatment of field and paddy soils near Pungjeong mine contaminated with arsenic and cationic heavy metals was investigated from batch and column experiments. Immobilization of heavy metals was evaluated by TCLP dissolution test. Immobility of heavy metal ions was less than 15% when steel slag alone was used. This result suggests that $Fe_2O_3$ and $SiO_2$, known as the major component of steel slag, have little effect for the immobilization of heavy metal ions due to acidity of TCLP solution. Immobilization of cationic heavy metals was little affected by the ratio of CaO and steel slag while arsenic removal was increased as the ratio of steel slag to CaO increased. In the column test, concentrations of both arsenic and cationic heavy metals in effluents were below the water discharge guideline over the entire reaction period. This result can be explained by the immobilization of cationic heavy metals from the increased pH in soil solution as well as by the formation of insoluble $Ca_3(AsO_4)_2$. From this work, it is possible to suggest that arsenic and cationic heavy metals can be concurrently stabilized by application of both CaO and steel slag.

• Journal of the Korean Ceramic Society
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• v.11 no.1
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• pp.29-35
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• 1974

Effect of calcium sulfate and barium sulfate on the formation of portland cement clinker was studied by means of chemical analysis. DTA and X-ray diffraction analysis. In the presence of liquid phase, effect of the additives on the formation of tricalcium silicate was examined according to the reaction, 2CaO.$SiO_3$＋CaO$\longrightarrow$3CaO.$SiO_3$, which is the principal reaction in portland cement clinkerization, and optimum conditions in firing clinker concerning amount of additive, firing time and temperature were determined, and its kinetics was referred to. The experimental results are summerized as follow: (1) Appropriate burning temperature range of cement clinker is more limited as the content of calcium sulfate in clinker is increased. Amount of calcium sulfate, firing time and temperature in proper condition of clinkerization is related to each others. Being added suitable quantity of calcium sulfate, firing temperature of clinker can be lowered about $100^{\circ}C$. (2) When 3-5 mole% of calcium sulfate is added, firing time of 15-30 minutes at about $1380^{\circ}C$ is reasonable, and if the content is over7 mole %, firing for 1 hr. or more at $1350^{\circ}C$ is anticipated to be optimum condition. (3) In the reaction of tricalcium silicate formation, the role of barium sulfate as a mineralizer is similar to that of calcium sulfate, but the optimum firing temperature of cement clinker containing barium sulfate tends to be 20-$30^{\circ}C$ higher than that of clinker containing calcium sulfate. (4) When barium sulfate is used as mineralizer, 2-3 mole % of it to tricalcium silicate is recommended and if it is added more than this amount, free CaO is increased rapidly in clinker and alite formation is inhibited.

• Korean Journal of Plant Resources
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• v.15 no.3
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• pp.279-284
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• 2002

To establish the mass propagation method of Typha orientatis Presl, several factors influencing seed germination were investigated. The best seed germination of T. orientalis was achieved under the light and 25~3$0^{\circ}C$ temperature. GA$_3$ tended to enhance seed germination, and 500 mg.L$^{-1}$ GA$_3$ showed 90.7% germination, which was 1.2 times of control. Compared to control, BA treatment prohibit seed germination. Especially, seeds were not germinated under 500 mg.L$^{-1}$ BA treatment. In case of KNO$_3$ and Ca(NO$_3$)$_2$ treatment, the germination rate was decreased by all concentrations, except 100 mM Ca(NO$_3$)$_2$.

• Tuberculosis and Respiratory Diseases
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• v.38 no.3
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• pp.287-296
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• 1991

Colonial morphology of the various yeasts often encountered in sputum or other clinical specimens was investigated on the corn meal-potato-yeast extract agar medium (GJCPY) containing orange-yellow pigments extracted from Gardenia jasminoides fruits in hopes of differential identification on primary cultures. The results obtained are as follows. 1) Cryptococcus neoformans which is a medically important yeast and whose colony showed brown to purple brown on GJCPY medium was distinguishable not only from buff colored Cr. laurentii after one week incubation but also from Candida spp. 2) Colony color of Candida albicans, a most common species in sputum specimens and of Ca. parapsilosis, a rare isolate, remained unchanged even after 15 days incubation. 3) Ca. tropicalis, second common isolate from sputums and Ca. krusei, a rare isolate, formed a characteristic rough and wrinkled colonies that permit to differentiate them from others. 4) Rare isolates, Ca. guilliermondii and Ca. lusitaniae, turned to prussian blue within three days of incubation. 5) Torulopsis sp. and Saccharomyces cerevisiae showed glossy grayish blue or light blue after one week incubation. The findings clearly showed that Ga. jasminoides pigments medium was useful to the morphological differentiation of medically important yeasts that were often encountered in sputum or other clinical specimens.

• Journal of the Korean Chemical Society
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• v.39 no.7
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• pp.524-529
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• 1995

The separation efficiency of metal ions by using silica gel bonded 15-crown-5 (SGBM) has been determined by column chromatography in aqueous solution at pH 1. Bindinng constants and separation factors for several SGBM-Metal interactions were measured in aqueous solution. The order of these binding constants and separation factors with metal ions was Li(Ⅰ) < Sr(Ⅱ) < Na(Ⅰ) < Cu(Ⅱ) < Mg(Ⅱ) < K(Ⅰ) < Ca(Ⅱ) < Bi(Ⅲ) < Sb(Ⅲ). These results were explained in terms of the size effect and electron density effect. This experimental results showed good efficiency for separation of $Sb^{3+}$ from mixtures of alkali, alkaline earth metal ions, and $Cu^{2+}$ in aqueous solution.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.2
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• pp.109-115
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• 1993

This study was designed to investigate the effects of dietary protein and calcium levels on Ca, Fe, Cu, Zn and Mg accumulation of the tissue of the Pb-administered rats. Male Sprague-Dawley rats were assigned to a 3$\times$3$\times$2 factorial design with 3 levels of protein (40%, 15%, 6%), 3 levels of Ca (1.2%, 0.6%, 0.12%) and 2 feeding periods (3 and 7 weeks). The control group was included separately. The rats were exposed to the drinking water containing 2,000ppm of lead. Calcium contents in serum, liver and femur were decreased with Pb administration. Calcium contents in serum and femur were reduced with dietary protein and Ca levels. Level of serum Fe showed no significant difference with Pb administration in the rats fed the high Ca diet. Iron content in liver was not affected by the lead when the rats fed the diet containing high protein and Ca. Level of serum Cu was lower in the Pb added groups than in the control group and tended to be reduced with decreasing dietary protein and Ca levels. Copper content in liver was not affected by the lead when the rats fed the high Ca diet. Level of serum Zn was decreased in the low protein-low Ca group. Magnesium content in serum was decreased with Pb administration when the rats fed the diet containing low protein and Ca. However, magnesium content in liver was reduced with Pb administration and affected only by dietary protein level.

• The Korean Journal of Nuclear Medicine
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• v.29 no.3
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• pp.294-306
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• 1995

There has recently been increasing interest in the use of NMDA receptor antagonists as potential neuroprotective agents for the treatment of ischemic stroke. To evaluate the neuroprotective effect of the selective non-competitive NMDA receptor antagonist MK-801 in focal cerebral ischemia, local cerebral glucose utilization (ICGU) was examined in 15 neuroanatomically discrete regions of the conscious rat brain using the 2-deoxy-D[$^{14}C$] glucose quantitative autoradiographic technique 24 hr after left middle cerebral artery occlusion (MCAO). Animals received MK-801 (5 mg/kg i.v.) or saline vehicle before (20-30 min) or after (30 min) MCAO. Both pretreatment and posttreatment of MK-801 increased occluded/non-occluded ICGU ratio in 7 and 5 of the 15 regions measured, respectively (most notably in cortical structures). Following MK-801 pretreatment, there was evidence of widespread increases in ICGU not only in the non-occluded hemisphere (12 of the 15 areas studied) but also in the occluded hemisphere (13 of the 15 areas studied), while MK-801 postreatment did not significantly increase ICGU both in the normal and occluded hemispheres. These data indicate that MK-801 has a neuroprotective effect in focal cerebral ischemia and demonstrate that MK-801 provides widespread alterations of glucose utilization in conscious animals.

• Bulletin of the Korean Chemical Society
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• v.15 no.2
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• pp.115-118
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• 1994

Samples of ($Bi_{2-x}Sb_x)PbSr_2Ca_2Cu_3O_y$, compositions with x=0.0, 0.1, and 0.2 were prepared by solid-state reaction. The solubility of Sb into the 2223 phase is lower than 0.05 for the ratio of Sb/Bi. The lack of stability of the Sb-substituted $Bi_2O_2$ double layers is likely to cause the solubility low. There is no great dependence of lattice parameters on the Sb-content, and bonds around the square-pyramidal Cu atom are not affected by the $Sb^{3+}$ ion substituted. The superconducting transition temperature of this system is decreased gradually with increase of Sb, which is tentatively attributable to the perturbation of the Bi 6p-O 2p band and/or to the low volume fraction of the 2223 phase.

• Microbiology and Biotechnology Letters
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• v.23 no.6
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• pp.717-722
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• 1995

Using a flocculating Saccharomyes cerevisiae CA-1, an air-lift reactor equipped with a modified settler was used for ethanol fermentation. The effects of conditions such as aeration rate, initial glucose concentration, and dilution rate were studied using the air-lift reactor. In batch fermentation, optimum aeration rate was 0.5 vvm. In continuous fermentation, aeration rate and initial pH were fixed 0.5 vvm and 4.5, substrate concentration and dillution rate were changed 10-15% and 0.1-1.3. The maximum ethanol productivity was shown to be 20.4 g/l$\cdot $h in 10% glucose and 0.7 h$^{-1}$ dilution rate., and optimum operation condition considering the ethanol productivity and glucose utilization ratio was 0.5 h$^{-1}$ dilution rate in 10% glucose concentration.