• Journal of Microbiology and Biotechnology
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• 제5권4호
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• pp.213-217
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• 1995

The effect of inorganic phosphate on the fermentative production of aminopeptidase M inhibitors MR-387A and B by Streptomyces sp. SL-387 has been studied. With inorganic phosphate concentrations higher than 0.78 mM, an inverse correlation was found between the maximum inhibitor production and the initial phosphate concentration added. Growth sensitivity of this actinomycete to arsenate, a phosphate analogue, and the use of magnesium carbonate, a phosphate-trapping agent, suggested that the inhibitor formation was under phosphate repression. Exogenous ATP further increased the degree of phosphate interference in both phosphate-repressed and non repressed culture conditions. The use of a phosphate analogue and a protein synthesis inhibitor also suggested that the phosphate itself repressed inhibitor formation.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2021년도 봄 학술논문 발표대회
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• pp.112-113
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• 2021

Phosphate based inhibitor is playing a decisive role in inhibiting the corrosion of steel rebar in chloride condition. We have used different amount of ammonium phosphate monobasic (APMB) as corrosion inhibitor in mortar with different amount of chloride ions. The compressive strength, flexural strength, open circuit potential (OCP), electrochemical impedance spectroscopy (EIS), potentiodynamic polarization resistance (PPR), scanning electron microscopy (SEM) and Raman spectroscopy were performed to access the effect of inhibitor on corrosion resistance. As the amount of inhibitor is increased, the compressive strength increased. The electrochemical results show that as the amount of inhibitor and chloride ions are increased, the total impedance and corrosion resistance of steel rebar increased attributed to the formation of the stable oxide films onto the steel rebar surface. It is suggested that APMB can work in high concentration of chloride ions present in concrete where phosphate ion helps in formation of stable and protective phosphate based oxide film.

• Environmental Engineering Research
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• 제17권1호
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• pp.17-25
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• 2012

Concern about green water problem has surfaced as a serious issue in Korea. In order to solve this problem, it is necessary to research inhibition of green water and corrosion control of copper pipe in water service. This paper discovered that moderate corrosion inhibitors can solve the green water problem and copper corrosion in water service by adding the optimal concentration of corrosion inhibitors based on regulation. Firstly, in the case of phosphate based corrosion inhibitors, as dosage of the corrosion inhibitor increases from 1 mg/L to 5 mg/L, the relative effect of corrosion inhibitor declines rapidly. Secondly, except for 1 mg/L dosage of silicate based inhibitor, relative effects of the inhibitor displays a positive number depending on inhibitor concentration. The most significant result is that the amount of copper release shows a downward trend, whereas the phosphate based inhibitor accelerates copper ion release as the inhibitor dosage increases. Thirdly, as the dosage of mixed inhibitors increases to 10 mg/L, the copper release change shows a similar trend of phosphate based inhibitor. Lastly, according to the Langelier saturation index (LI), silicate based inhibitors have the most non corrosive value. Larson ratio (LR) indicates that phosphate based inhibitors are the least corrosive. Korea water index (KWI) represents that silicate based inhibitors are most effective in controlling copper pipe corrosion.

• 환경영향평가
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• 제14권1호
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• pp.17-24
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• 2005

This study was performed to evaluate the adsorption rate of phosphate corrosion inhibitor and reaction rate constant in drinking water distribution systems. The optimum concentration of corrosion inhibitor would vary depending on the quality of water, pipe materials, and condition of metal surfaces. The current adsorption study indicated that the residual phosphate concentration of the corrosion inhibitor decreased with the time as it adsorbed on the surface of pipe material. As time went by, the residual phosphate concentration became constant. It means that the formation of the corrosion protection film on metal surfaces is completed.

• KSBB Journal
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• 제8권4호
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• pp.375-381
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• 1993

토양으로부터 세포외로 lipoxygenase inhibitor를 생산하는 균주를 screemng하여 우수한 저해능을 가지는 곰팡이 1균주 (L242H)를 분리하였고, 분리한 균주 L242H로부터 lipogenase inhibitor 생산조건을 검토하였다. 분리한 균주의 배양학적. 형태학적 특성을 조사해 본 결과 Penicillium속으로 동정되었다. Penicillium L242H의 플라스크 배양에 의한 lipoxygenase inhibitor 최적배양조건은 3.0% glucose, 0.4 % ammonium sulfate, 0.1 % potassium p phosphate (dibasic), 초기 pH 7.0이었고, 500ml용 shake flask에 배지 100ml를 넣어 8일간 배양했을 때 lipoxygenase inhibitor가 최대로 생산되었다.

• 한국임상약학회지
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• 제9권1호
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• pp.62-65
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• 1999

Inorganic phosphate (Pi) in rabbit plasma was found to block completely phosphotyrosine phosphatase (PTPase) activity without affecting the alkaline phosphatase (ALPase) activity. Our results provided that (1) PTPase activity and inhibitor are separated after G-25 gel-filtration. (2) This inhibitor is heat stable and trypsin-resistant and it can be removed by dialysis using 3 Kd cut-off tubing. (3) The elution pattern of the inhibitor is identical to that of Pi, and by performing a seperate run with inorganic phosphate. (4) The PTPase activity was recovered following an incubation with $CaCl_2$ (10 mM).

• Journal of Nutrition and Health
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• 제49권1호
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• pp.59-62
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• 2016

Purpose: Zinc, a biomineral present within and outside cells, manages various cellular mechanisms. In this study, we examined whether zinc was involved in vascular smooth muscle cell (VSMC) calcification via regulation of calcification inhibitor protein, osteopontin (OPN). Methods: Rat aorta cell line (A7r5 cells) and primary vascular smooth muscle cells (pVSMCs) from rat aorta were cultured with phosphate (1-5 mM) and zinc ($0-15{\mu}M$) as appropriate, along with osteoblasts (MC3T3-E1) as control. The cells were then stained for Ca and P deposition for calcification examination as well as osteopontin expression as calcification inhibitor protein was measured. Results: Both Ca and phosphate deposition increased as the addition of phosphate increased. In the same manner, the expression of osteopontin was upregulated as the addition of phosphate increased in both cell types. When zinc was added, Ca and P deposition decreased in VSMCs, while it increased in osteoblasts. Conclusion: The results imply that zinc may prevent VSMC calcification by stimulating calcification inhibitor protein OPN synthesis in VSMCs.

• 한국산학기술학회논문지
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• 제9권2호
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• pp.493-499
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• 2008

본 연구는 가정 옥내급수관에 적수 및 탁수 등을 유발하고 철, 구리 등 중금속이 용출될 수 있는 부식 문제 해결을 위해 인산염계 부식억제제를 주입하는 회분식 실험을 통해 옥내급수관으로 가장 많이 사용되고 있는 아연도 강관의 표면 도금이 벗겨진 상태인 탄소강관을 대상으로 주요 수질인자의 변화, 철의 용출농도 변화, 부식도 및 부착도 평가, 시편의 상태를 고찰하였다. 탄소강관에서 부식억제제를 주입하였을때 pH, 전기전도도, 알칼리도, Ca-경도 등의 부식성 수질인자는 약간의 변화가 있었으나, 큰 영향은 없었다. 탁도의 경우 부식억제제를 5 mg $P_2O_5/L$ 주입시 주입하지 않은 것에 비해 약 10배정도 낮게 나타나 부식억제제가 탁도 유발 억제에 큰 효과가 있음을 확인하였다. 부식억제제의 주입농도가 5 mg $P_2O_5/L$일 때까지는 부식억제제 농도가 증가함에 따라 철(Fe) 용출농도와 부식도가 서서히 감소하는 경향을 보였으며, 부식억제제 5 mg $P_2O_5/L$ 주입시 급격히 감소하여 부식억제제를 주입하지 않은 경우보다 각각 약 12.2배, 약 24배의 저감 효과를 보였다. 결론적으로 인산염계 부식억제제 약 5 mg $P_2O_5/L$ 주입은 옥내 급수관 내부 표면에 치밀한 방식 피막을 형성하여 부식제어에 효과가 있을 것으로 판단된다.

• 상하수도학회지
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• 제19권2호
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• pp.228-237
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• 2005

The main purpose of this study was to investigate the red water reducing effects of phosphate based inhibitor when it was applied to water distribution system. The effects of pH, alkalinity, calcium concentration in the reduction of the red water also studied. The most finished water in Korea showed relatively high corrosiveness and was required to introduce some types of corrosion reducing methods such as addition of alkalinity. The precipitation of $CaCO_3$ by addition of $Ca(OH)_2$ formed porous film on the surface of the carbon steel pipes and was displaced easily from the surface of the pipes; on the other hand, addition of zinc phosphate (ZOP) formed reliable film on the surface and reduced iron release and color. Although the main function of ZOP was to suppress the release of Pb and Cu, it also reduced iron concentration released from water distribution pipes.

• 한국환경보건학회지
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• 제29권3호
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• pp.65-71
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• 2003

The injection concentration of corrosion inhibitor increases under the pH 7, temperature of 2$0^{\circ}C$, and alkalinity of 35 mg/l (as CaCO$_3$), the corrosion rate gradually decreased. When the corrosion inhibitor of 10 mg/l is injected, the corrosion rate for carbon steel pipe, galvanized steel pipe, and copper pipe reduces for 37, 66 and 61 % respectively that it is more efficient on galvanized steel pipe and copper pipe. As a result of examination of corrosion rate at pH 6, 7, and 8 when injecting 10 mg/l of corrosion inhibitor under the conditions of 2$0^{\circ}C$ in water temperature and 35 mg/l (as CaCO$_3$) in alkalinity, the efficiency of the corrosion inhibitor increases as the pH increases. For carbon steel pipe, it does not show much a difference with the change of the pH condition, but galvanized steel pipe and copper pipe clearly show the corrosion rate depending on the change of the pH condition. The efficiency of corrosion inhibitor is low as the concentration of residual chlorine is high, but it does not show a great influence at 0.4 mg/l or less. For each pipe type, in the case of carbon steel pipe, the range of increase of corrosion speed following the residual chloride is higher than the other pipe types. In the meantime, the effect following the residual chlorine in copper pipe is low.