• Journal of the Korean Society for Marine Environment & Energy
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• v.3 no.2
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• pp.3-10
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• 2000

The main purpose of this study were to estimate the benthic fluxes of dissolved inorganic nitrogen (DIN) from the sediment and denitrification rates in tidal flats of the Keum river estuary. Sediment specimens were collected by a core sampler from three stations along the Keum river estuary in April, August and December, 1999. The sediments were composed of 1.18 %, 29.34 % and 69.49 % of gravel and sand, sand and silt, respectively. The mean ignition loss of the sediment was found 6.7 % and its Oxidation Reduction Potential (ORP) was measured -12 mV. The total hydrogen sulfides was determined about 0.26 mg/gㆍdry. The estimated outflux of ammonium was found 11.2 m mole N/m²ㆍday from the sediment, whereas -1.09 m mole N/m²ㆍday of influx was obtained for nitrate and nitrite through the incubation experiment of sediment cores. Total DIN flux was 10.2 m mole N/m²ㆍday outflux from the sediment. From the incubation experiments executed with the flux studies, mean denitrification rate was found 30.6 m mole N₂/m²ㆍday measured by the direct assay of N₂ production technique. On the basis that DIN flux and denitrification rate in sediment of tidal flat of the Keum river estuary are may be effects to control the algal biomass in the coastal environment, it seems inevitable to pay more attention to investigate the flux of DIN and denitrification rate in tidal flat of the Keum river estuary.

• Journal of the Korean Ceramic Society
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• v.25 no.6
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• pp.631-638
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• 1988

Effect of Ca/P mole ratio on the precipitates and powder properties of hydroxyapatite was investigated. Powder and precipitates of hydroxyapatite were synthesized by the reaction of Ca(NO3)2.4H2O and (NH4)2 HPO4 solutions at room temperature. The pH value and compositions (Ca/P mole ratio) in starting solutions were 11 and 1.64-1.79(or 1.85), respectively. Rodlike hydroxyapatite precipitates were agglomerated together. The average agglomerated particle size was ranged from 2-8${\mu}{\textrm}{m}$. Among compositions, the minimum agglomerated particle size was shown at the Ca/P mole ratio 1.75. CO2 was contained in hydroxyapatite powders and these ultrafine powders had poor crystallinity. The specific surface area and specific total pore volume of hydroxyapatite powders were 104-137$m^2$/g and 0.396-0.467cc/g, respectively. When the Ca/P mole ratio was 1.75, these values were the maximum. And water content increased with the Ca/P mole ratio(Ca/P mole ratio>1.67). In most cases, hydroxyapaite was stable to 130$0^{\circ}C$. However, in the case of Ca/P mole ratio 1.64, hydroxyapatite was changed to $\alpha$-whitlockite at 120$0^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.6 no.3
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• pp.177-184
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• 1974

File fish Navodon modestus was dehydrated in cabinet type hot-sir drier at $48-50^{\circ}C$ for 11 hours and also yellowfin puffer Fugu xanthopterum was dried in open air at $26-28^{\circ}C$ for 30 hours. Nucleotides and their related compounds were collected by extraction with cold perchloric acid and their amounts were determined by anion exchange column chromatography. The contents of ADP, IMP, ATP and hypoxanthine in fresh file fish muscle were 22.9, 12.1, 4.9, and 3.2 ${\mu}mole/g,$ dry wt. respectively. AMP and inosine were 0.9 ${\mu}mole/g,$ dry wt. equally. In fresh yellowfin puffer muscle, the contents of ADP, ATP, AMP, inosine and hypoxanthine were 25.6, 2.4, 1.6, 0.3, 0.6, and 0.4 ${\mu}mole/g,$ dry wt. respectively. In the case of file fish, ADP and ATP tended to degrade rapidly during hot-air dehydration. The contents of IMP were decreased slightly while AMP and inosine were increased. And another case of yellowfin puffer, ADP also tended to degrade rapidly during sun drying while AMP, IMP, inosine and hypoxanthine were increased. Especially, in both case of file fish and yellowfin puffer, inosine was increased twenty five and thirty five times during drying respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.17 no.1
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• pp.73-76
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• 1988

The postnatal changes of taurine in human breast milk were examined. Breast milk samples were collected at 3-5 th day and 30 th day after delivery. Taurin content of colostrum and mature milk was 424n mole/ml and 294.4n mole/ml, respectively, The content of taurine was slight decrease during breast- feeding.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.10 no.4
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• pp.213-220
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• 1977

In this study, physical and chemical properties of sea water were investigated qualitatively from the data measured by means of the conductive method as described in the previous paper. The activation energy, ${\Delta}E$, calculated from the suggested equation describing the electrical conductive property of sea water was about 3.0 to 4.0 Kcal/mole at a given pressure and concentration. The average values of the activation volume change, ${\Delta}V$, over the pressure 1 to 1,200 bars decreased from -1.30 to $-0.27\;cm^3/mole$ as the temperature increased from 10 to $25^{\circ}C$.

• Applied Chemistry for Engineering
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• v.9 no.5
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• pp.786-790
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• 1998

K-GIC of the new carbon electrode to improve performance of carbon negative electrode in lithium ion secondary battery was prepated and its electrical characteristics were studied. Form this study, intercalated K quantity was increased in order of $2>3>1mole/{\ell}$ of KCl solution. And, for KCl solution of 1mole, the mole ratio of carbon and potassium was 156~388 carbon/potassium. The proper condition of K-GIC preparation was KCl solution of $1mole/{\ell}$, reaction temperature of $700^{\circ}C$, reaction time of 1 hour. From this condition, the intercalation and deintercalation behavior of lithium was very excellent. Also the reversibility was excellent.

• Korean journal of food and cookery science
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• v.2 no.2
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• pp.1-7
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• 1986

Gulbi were made by salting Yellow corvenia (Pseudosciaena manchurica) with the in three ways: the dry salting method with bay salt, the dry salting method with purified salt or with the abdominal brine injection method with purifie salt. The half of the sample was dried by the control system of temperature and humidity: the other part was dried by the natural condition. In fresh muscle, the content of IMP, hypoxanthine, inosine and AMP were $13.40,\;9.28,\;3.01{\mu}mole/g$ and trace amount, dry basis, respectively. In fresh egg, the content of AMP, hypoxanthine, inosine and IMP were 13.98, 6.56, 1.98 and $1.93{\mu}mole/g$, dry basis, respectively. During the drying process of Yellow corvenia, the content of hypoxanthine increased remarkably, while the content of AMP, IMP and inosine decreased ana remained as trace amount. It can be suggested that the characteristic flavor of Gulbi is not attributed to the nucleotides and their related compounds but rather to free amino acids.

• Journal of the Korean Ceramic Society
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• v.26 no.1
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• pp.123-131
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• 1989

Hydroxyapatite powders were syntehsized by the reaction of Ca(NO3)2.4H2O and (NH4)2HPO4 in aqueous solution. The effect of the Ca/P mole ratio in the starting solution on the sintering of the powders and its microstructure was studied. When the Ca/P mole ratio in the starting solution was 1.69, the relative density of the sintered bodies was more than 95%. The sinterability was decreased as the Ca/P mole ratio in the starting solution was increased (Ca/P mole ratio >1.67). Hydroxyapatite sintered bodies obtained from the Ca/P mole ratio=1.69 had very excellent bending strength. The best bending strength was obtained at 110$0^{\circ}C$ and its value was 1220kg/$\textrm{cm}^2$. The average grain size was 0.277${\mu}{\textrm}{m}$. Most of sintered bodies were almost shown 100% hydroxyapatite phase. However, in case of the Ca/P mole ratio=1.64 hydroxyapatite was decomposed to $\alpha$-whitlockite above 120$0^{\circ}C$.

• Journal of Pharmaceutical Investigation
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• v.1 no.1
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• pp.78-84
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• 1971

The comparative studies were made on Salicylamide, used individually and compounded with antihistaminics as regards. (1) the absorption rate through isolated rat small intestine (in vitro) (2) the absorption rate through rat small intestine (in vivo), and the following effects were found. 1. The Absorption velosity of 2 m Mole gm. of salicylamide in the small intestine were decreased, when the agents compounded with tripelennamine indicating the greatest absorption inhibition in the case of m Mole gm. of tripelennamine. 2. The Absorption velosity of 2m Mole gm. of salicylamide in the small intestine were decreased, when the agents compounded with diphenhydramine indicating the greatest absorption inhibition in the case of 2m Mole gm. of diphenhydramine. 3. The Absorption velosity of 2m Mole gm. of salicylamide in the small intestine were increased, when the agents compounded with chlorpheniramine indicating the greatest absorption augmentation in the case of 0.2m Mole gm. of chlorpheniramine.

• Journal of the Korean Ceramic Society
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• v.27 no.2
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• pp.155-160
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• 1990

Al-rich Mg-Al spinel single crystals were grown by Verneuil process using oxygen and hydrogen flame. Spinel single crystals were grown in chemical compositions from MgO : Al2O3 mole ratio 1 : 1 to 1 : 3. Mole ratio 1 : 1 was hard to be grown and mole ratio 1 : 2.5 and 1 : 3 were grown well. Selecting well-grown mole ratio 1 : 3, seeds were prepared having [100], [110] and [111] orientation respectively. Growth rate were highest in [100] orientation and lowest in [111] orientation.