• 한국식품영양학회지
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• 제6권3호
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• pp.169-177
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• 1993

The conversion of glutamate by glutamine synthetase Is the endergonic reaction that demands ATP as its energy source. In order to supply efficiently ATP that is demanded in the conversion of glutamate to glutamine, the ATP- generating system by acetate kinase partially purified from Escherichia coli K-12 was coupled with glutamine synthetase partially purified 5. coli K-12 Pgln6. The optinum conditions of the coupled reaction were investigated. As the result, the highest conversion of glutamate to glutamine was shown In the reaction mixture containing 100mM glutamate, 100mM NHtCl, 50M acetyl phosphate, 5mM ADP, 40M MgCl2, 300mM potassium phosphate buffer (pH 7.5), 5mM MnCl2, Under this condition, the most effective concentrations of enzyme were 70unit/ml glutamine synthetase and 99unit/ml acetate kinase. Under the optinum conditions, 98% of 100mM glutamate was converted to glutamine within 6 hours.

• Archives of Pharmacal Research
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• 제23권3호
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• pp.197-201
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• 2000

In an aqueous piperacillin sodium solution, a well-defined single wave or single peak was observed by direct current(DC) polarography or differential pulse polarography(DPP). The peak potential change per pH unit was -54 mV in the phosphate buffer at $18^{\circ}C$, which indicated that protons were involved in the electrochemical reduction of the 2,3-dioxopiperazine moiety of piperacillin sodium with a $H^{+}e^{-}$ ratio of one. Using a phosphate buffer of pH 4.3, the $1.0{times}10^{-7}$ M piperacillin sodium single peak could be determined by DPP with relative standard deviation of 1.6 %(n=3). Piperacillin sodium could be analyzed with-out interference from penicillin G-potassium, which enabled the employment of DPP as a fast and simple technique for monitoring the synthetic process of the antibiotic.

• 한국학교ㆍ지역보건교육학회지
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• 제12권3호
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• pp.89-99
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• 2011

Objectives: The aim of this study was to assess an association between nutrient intake and prevalence risk of deciduous dental caries among preschool children. Methods: A total of 922 children aged 3 to 5 years was selected from the database of Fourth Korean National Health and Nutrition Examination Survey(KNHAINS). Data were included socio-demographic characteristics, oral health related behaviour, nutrient intake(carbohydrate, protein, fat, calcium, phosphate, iron, sodium and potassium), and oral health status(dft index). To assess the crude and adjusted associations, logistic regression analysis were applied considering a complex sampling design. Results: Children who were more consumed protein, calcium, phosphate, iron and sodium had slightly lower prevalence risk of deciduous dental caries after adjusting for socio-demographic characteristics and oral health related behaviour. Moreover, prevalence risk of the highest intake of phosphate and sodium(3rd tertiles) was significant lower than that of the lowest intake(1st tertiles). Conclusion: The nutrient intake was slightly associated with the prevalence risk of deciduous dental caries.

• 한국작물학회지
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• 제13권
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• pp.119-126
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• 1973

질소 및 가리 동일수준에서 중과석, 복합비료, 용성인비시 인산비료가 맥류의 생육 및 수량에 미치는 영향을 검토코저 수원, 이리, 광주 및 대구에서 실시한 시험결과를 요약하면 다음과 같다. 1. 출수 및 성숙기는 무인산구에 비하여 4개소 모두 비중에 관계없이 빨라졌으며 특히 수원, 광주에서는 타비료보다 용성인비 시용구에서 다소 조숙화 경향을 볼 수 있었다. 2. 인산비료의 증시에 따라 질소를 증시할 경우 용성인비 8kg시용 까지는 동일수준의 중과석 단용구보다는 증수되나 12kg으로 증시될 경우는 광주, 수원을 제외하고 비중간 차이를 인정할수 없었다. 3. 등숙은 대체적으로 용성인비구가 타비료보다는 향상되어 증수의 요인이 되었는데 이것은 용성인비에 함유된 부가적 성분의 효가로 추측된다. 4. 인산비료의 시용량에 있어서는 4개소 모두 10a당 8kg 내외가 적정량으로 보여지며 4kg시용은 수량면에서 볼 때 각시험지에서 8kg시용구보다 감수되었고, 12kg 시용구는 광주를 제외하고는 비슷하거나 감수되었다. 5. 용성인비의 4kg 시용구가 감소된 것은 용성인비의 인산성분이 구용성이기 때문에 유효태 인산의 절대량이 적은데 기인하는 것으로 보여지며 증비에 의하여 절대량이 증가할 경우에는 용성인비의 효과가 타인비보다 큰 것으로 보여진다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제20권6호
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• pp.28-36
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• 2015

Simultaneous mobility reduction of explosives and heavy metals in an operational range by monopotassium phosphate (MKP) and bentonite spreading technology was investigated. Potassium ion and phosphate ion in MKP act as explosives sorption enhancer and insoluble heavy metal phosphate formation, respectively, while bentonite acts as the explosives adsorbent. Then, the decrease in surface water concentration of the pollutants and resulting risk reduction for local residents of the operational range, by MKP/bentonite application was estimated. Under untreated scenario, the noncancer hazard index (HI) exceeded unity on February, July and August, mainly due to 2,4,6-trinitrotoluene (TNT); however, MKP/bentonite treatment was expected to lower the noncancer hazard index by decreasing the surface water concentration of explosives and heavy metals (especially TNT). For example, on July, estimated surface water concentration and HI of TNT were 0.01 mg/L and 1.1, respectively, meanwhile the sorption coefficient of TNT was 3.9 mg¹⁻ⁿkg⁻¹Lⁿ. However, by MKP/bentonite treatment, the TNT sorption coefficient increased to 113.8 mg¹⁻ⁿkg⁻¹Lⁿ and the surface water concentration and HI decreased to about 0.002 mg/L and 0.2, respectively. Based on the result, it can be concluded that MKP/bentonite spreading is a benign technology that can mitigate the risk posed by the pollutants migration from operational ranges.

• 한국미생물·생명공학회지
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• 제30권3호
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• pp.258-263
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• 2002

E. faecalis RKYl을 이용한 젖산발효에서 세포성장과 젖산 생산에 대한 배양온도 및 pH의 영향을 조사한 결과온도가 낮을수록 세포성장은 향상되었으나 발효시간이 지연되어 젖산생산이 저하되었으며$ 50^{\circ}C$에서는 세포성장이 거의 없었다. pH 7.0-9.0에서 거의 비슷한 세포성장 및 젖산생산을 보였으나 pH 6.0에서는 세포성장이 저하되었고 발효시간이 지연되었으며, pH 10.0에서는 세포성장이 거의 없었다. E. faecalis RKY에 의한 젖산발효는 비교적 넓은 범위의 배양온도($34- 46^{\circ}C$)및 pH(7.0-9.0)에서 안정하였으며 최적 배양온도 및 pH 는 각각 $42^{\circ}C$, 7.0이었다. 또한 일반적으로 일인산염에 비해 이인산염을 첨가해 주었을 때 젖산생산성이 향상되었으며, 효모추출물 10g·$L^{-1}$을 질소원으로 사용하여 배양하였을때 $Mg^{2+}$ 과 $Mn^{2+}$의 첨가효과는 없는 것으로 나타났다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제16권5호
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• pp.31-41
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• 2011

The objectives of this study were to investigate the efficiencies of the stabilizers such as mono-potassium phosphate (MKP), phosphate fertilizer and red mud in treating the mine tailings contaminated with heavy metals and to characterize the changes in fractionations of the heavy metals during the stabilization. The TCLP results showed that the stabilization efficiencies of Cd, Pb and Zn increased with the increase in the stabilizer dosage and the reaction times. MKP showed the highest efficiencies for the heavy metals stabilization among the stabilizers tested. When the mine tailings were amended with MKP, the TCLP concentrations of Cd, Pb and Zn were reduced by 79~97%, 61~84%, and 89~99%, respectively. When the composite stabilizers, MKP/phosphate fertilizer or MKP/red mud, were used, the stabilization efficiencies were lower than when MKP was used as a single stabilizer. The sequential extraction results showed that carbonates fraction of Cd and Zn increased generally. Especially, when red mud was used, carbonates fraction of Cd and Zn increased 5 and 18 times, respectively. In the case of Pb, the treatment with MKP increased residual fraction by 10 times. The results showed that MKP was the most effective in stabilizing the heavy metals (Cd, Pb and Zn) to improve the efficacy of the composite binders.

• Korean Chemical Engineering Research
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• 제50권5호
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• pp.789-794
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• 2012

폴리머 시멘트 몰타르 혼화용 라텍스를 개발할 목적으로 carboxylated styrene butadiene 라텍스를 2단계 유화중합법으로 제조하고 시멘트 몰타르에 적용하는 실험을 수행하였다. 카르복실 모노머는 methyl methacrylate, methacrylic acid와 acrylic acid를, 중합 모노머는 styrene과 butadiene을, 분자량 조절제는 t-dodecyl mercaptan을, 가교제는 divinyl benzene을 선정하고 사용량을 실험으로 결정하였다. 음이온 유화제는 sodium dodecylbenzene sulfonate와 sodium salt of lauryl sulfate를, 라텍스 안정제로 nonylphenoxy poly(ethyleneoxy) ethanol 계열의 동족체들(n=10, 20, 40)을, 그리고 potassium persulfate와 sodium bisulfite를 redox 개시제로, sodium monohydrogen phosphate와 potassium carbonate를 전해질로 사용하였다. 카르복실 모노머의 종류와 사용량, styrene과 butadiene의 단량체비 및 분자량 조절제와 가교제가 라텍스의 기본물성과 몰타르 공시체의 역학적 강도에 미치는 영향을 실험적으로 고찰하여 폴리머 시멘트 몰타르 포장재용 라텍스 제조에 적합한 중합처방을 제시하였다. 또, 이 중합처방에 의해 제조한 라텍스를 폴리머 시멘트 몰타르의 적용성을 시험한 결과, 경화시간 28일에서 품질 기준보다 압축강도는 25.4%, 휨강도는 45.3% 증진된 강도의 발현 특성을 확인하였다.

• 한국환경농학회지
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• 제41권3호
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• pp.158-166
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• 2022

BACKGROUND: Kiwifruit is a fruit tree with relatively small cultivation area in Korea and researches on its soil and physiology are very limited compared to those on cultivar development. Therefore, there are limited information for farmers to cope with the reduction in productivity due to various physiological disorders and premature aging. This study was conducted to investigate the soil and leaf chemical properties, and fruit characteristics, which will be used as basic data for stable kiwifruit orchard soil management. METHODS AND RESULTS: The soil and leaf chemical properties, and fruit characteristics were investigated for two years in 16 kiwifruit orchards growing 'Hayward' (Actinidia deliciosa) in Jeollanam-do and Gyeongsangnam-do. Soil and leaf samples were collected in July and fruit quality was investigated by harvesting fruits about 170 days after full bloom. The average soil chemical properties of kiwi orchards were generally higher than the recommended level, except for pH, and especially, the exchangeable potassium reached about 300% of the recommended level. The proportions of orchards that exceeded the recommended level of soil chemical properties were 63, 31, 100, 69, 94, 88 and 69% for pH, EC, organic content, available phosphate, and exchangeable potassium, calcium and magnesium, respectively. Thirty-three percent of orchards had more than 100 mg/kg of nitrate nitrogen in soil. Available phosphate in soil showed a significantly positive correlation with leaf nitrogen, phosphoric acid and calcium content, but showed a significantly negative correlation with leaf potassium content. The magnesium content in the leaves was significantly correlated with soil pH. The highest fruit weight was observed in about 25 g/kg of leaf nitrogen content which could be attained when plants were grown on the soil containing about 100 mg/kg of nitrate nitrogen content. The average soluble solids content among 16 orchards was 9.58 °Brix at harvest and 13.9 °Brix after ripening, which increased about 45%, and the average fruit weight was about 110 g. CONCLUSION(S): For fruit quality, fruit soluble solids (sugar compounds) content was significantly correlated with leaf potassium content, fruit hardiness with leaf total nitrate, calcium and magnesium, and fruit titratable acidity with leaf magnesium; however, leaf calcium and magnesium negatively affect the soluble solids contents in fruits.

• 한국잠사곤충학회지
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• 제20권2호
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• pp.1-5
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• 1978

숙전뽕밭에서의 연산 및 가리시비양이 뽕잎수량에 미치는 영향을 알기 위해 색소, 연산 및 가리의 표준시비량을 25-11-15kg/l0a으로하고 색소의 시비량을 25kg/l0a 으로 고정시킨 후, 연산질을 Po, P$^1$/$_2$,P$_1$ 및 P$_2$로, 가리질을 $K^1$/$_3$, $K^2$/$_3$, $K_1$ 및 $K_1$및 $K_2$등으로 시비수준을 달리하고 시험한 결과 다음과 같았다. 1. 시비처리구 수량의 유의차는 3년째 추기에 무시비구에서만 나타났으며, 연산질비료의 감량에 따라 수엽량은 6.4~11.5%. 가리질의 경우에는 2.7~5.9%감수를 보였으나 유의차는 인정되지 않았다. 2. 연산 및 가리질 비료의 배량증시에도 수량의 증가는 없었다. 3. 시용가리질의 토양중 이동은 매우 높은 반면, 연산의 이동은 지극히 불량하였다. 이상의 결과에 의해 연산질비료는 현수준 (11kg/l0a)이 합리적인 양이며, 가리질은 5~10kg/l0a까지 절감시켜도 3년간은 수량에 유의성있는 영향은 없는 것으로 사료되었다.