• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2001년도 추계학술발표대회
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• pp.594-597
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• 2001

RhodopseudolllOllas palustris P4 was studied for $H_2$ production from glucose in batch culture. Important conditions studied include phosphate concentration, initial pH, temperature, glucose concentration, and gas-phase replacement. Optimal $H_2$ production was observed at 60 - 300 mM of phosphate and 7.8 - 8.6 of initial pH. The effect of culture temperature was negligible When glucose concentration increased from 0.1 to 5% (w/v), $H_2$ production increased up to 2% and remained constant thereafter. Intermittent purging of the reaction botlle with Ar gas stimulated the Hl production by alleviating the inhibition by $H_2$. The maximum productivity was 111.1 ml $H_2$/h-1.

• Biotechnology and Bioprocess Engineering:BBE
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• 제7권4호
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• pp.231-233
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• 2002

The potential of calcium peroxide to act as an agent for waterblooming control was In-vestigated by examining the growth inhibition of Microcystis aerusinosa. Due to the chemical nature of calcium peroxide, it can remove dissolved phosphate by forming an Insoluble precipitate, generating radicals, coagulant, and oxygen as byproducts as it dissolves in water. The growth of M. aerusinosa was severely inhibited and the chlorophyll-n concentration was drastically decreased in the presence of calcium peroxide. With 200 ppm of calcium peroxide dosage, a chlorophyll-a concentration of 1,700 mg/m$^3$ was lowered to below 10% of its initial concentration after 4 days. One possible explanation for this growth Inhibition is the removal of the available phosphate by calcium peroxide.

• Journal of Nutrition and Health
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• 제28권2호
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• pp.127-136
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• 1995

In this study, the nutritional composition of colostrum milk obtained from 22 mothers delivering perterm infants and 17 mothers delivering term infants was analyzed. The energy content of colostrum was yielded based on nitrogen, lactose, and lipid data. Preterm milk is more close the nutritional needs of the preterm infant than dose other breast milk. The results are as follows : 1) Protein concentration was significantly higher, but carbohydrate and lipid concentration were lower in preterm milk than fullterm milk. Energy content yielded from total nitrogen, lactose and lipid concentration was higher in the fullterm milk than preterm milk. 2) Calcium was higher in the preterm milk than fullterm colostrum. Phosphate was lower in fullterm milk than pretem milk. Calcium/Phosphate ratio were 2.61/1 in the preterm and 2.06/1 in the fullterm milk. Magnesium was higher in the preterm milk than fullterm milk. Zinc, Copper and Manganese concentrations were tended to lower in the preterm milk than fullterm milk.

• KSBB Journal
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• 제4권2호
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• pp.134-142
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• 1989

Aureobasidium pullulans에 의한 세포외 다속류 생성연구를 통한 결론은 다음과 같다. (1) sucrose 농도가 50 g/l 이상일 때는 기질에 의한 저해 작용이 나타나고 있음을 알았으며 실소원의 증가에 따라서 균체량은 증가하지만 세포외 다속류 생성은 최적농도 (1 g/l )까지 증가하고 그 이상에서는 감소했으며 멜라닌 색소 출현시간은 길어졌다. (2) 최대 균체 성장은 초기 pH 3.0에서 보인 반면에 세포외 다속류 생성은 초기 pH 7.5에서 최대 값은 나타내었고 최대 PH가 증가함에 따라서 효모형 비율이 증가했으며 멜라닌 색소 출현시간은 pH 4.5~8까지는 거의 일정하게 나타났지만 pH 3 이하에서는 전혀 멜라닌 색소가 나타나지 않았다. (3) 탄소원과 실소원을 증가시켰을 때 pH 5 이하에서는 멜라닌 색소는 나타나지 않았으나 pH 6에서 pH 8.5 로 pH가 높아짐에 따라 멜라닌 색소는 빨리 나타나는 경향을 보였다. (4) 용존산소 농도가 높을수록 균체량과 세포외 다속류 생성이 증가했고 멜라닌 색소 출현시간이 빨라졌으며 potassium phosphate가 전혀 들어있지 않는 배지에서는 멜라닌 색소 출현은 관찰할수가 없었다.

• Nutritional Sciences
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• 제3권1호
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• pp.31-35
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• 2000

The purpose of this study was to compare the changes in PLP concentrations induced by regular, moderate, and abrupt, high-intensity exercise in the plasma and tissues of vitamin B6 deficient and normal rats. Forty-eight rats were fed either a vitamin B6 deficient (-B6) diet or a normal (+B6) diet for 5 weeks and were subdivided into 4 groups:non-exercise(NE) group: regular, moderate-intensity exercise (RME) group; abrupt, high-intensity exercise (AIE) group; abrupt, high-intensity exercise and recuperation(IRE) group. The RME group was exercised on treadmill ($10^{\circ}$, 0.5-0.8km/h) for 2 hours just before sacrifice at the end of 5th week on the diet and the IER group was recuperated for three days on the diet after being exercised like the AIE group. Pyridoxal 5 -phosphate(PLP) levels were compared in the plasma, liver and skeletal muscle of the rats. Plasma PLP concentration tended to decrease in -B6 rats and tended to increase in +B6 rats with AIE. Plasma PLP concentration in both +B6 rats with AIE and no change in both -B6 and +B6 rats with RME. Muscle PLP concentration decreased in +B6 rats, showed no change in -B6 rats with AIE. Muscle PLP concentrations in both +B6 and -B6 rats did not change with RME. Plasma PLP, liver PLP and muscle PLP concentration of IER returned to those of NE in both +B6 and -B6 rats. These results suggest that changes in PLP concentration in plasma, liver and muscle occur with exercise and are affected by exercise intensity and vitamin B6 status. These changes may be due to interorgan redistribution of PLP.

• 유기물자원화
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• 제29권2호
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• pp.25-30
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• 2021

본 연구는 인산염 인 농도 측정과 관련하여 숙련도에 의해서 정도관리의 지표가 어떻게 개선되는지를 조사하였다. 아울러 분석기기의 종류에 따른 측정값의 차이가 있는지 함께 비교하였다. 분석자의 숙련도가 분석결과에 미치는 영향을 알아보기 위해 3인의 실험자가 2종의 분석기기를 사용하여 수질오염공정시험기준에 따라 인산염 인을 7회에 걸쳐서 방법검출한계와 정량한계를 측정하였으며, 실험결과 5회 이상 반복실험하면 정도관리지표를 만족하였다. 인산염 인의 정량한계는 0.02 mg/L로 계산되었으며, 분석기기가 다른 경우 정량한계 부근의 시료에 대한 흡광도와 농도가 통계적으로 유의미하게 차이가 있음을 확인하였다.

• 한국토양비료학회지
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• 제37권1호
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• pp.36-40
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• 2004

최근에는 친환경 농업을 위하여 사용되는 미생물 비료의 안정성 유지와 효능, 저장 및 운송 등에 대한 어려움 및 불편함을 극복하기 위해서 미생물을 담체에 고정화하여 생물비료로 사용하고 있다. 본 실험에서는 인산가용화 미생물인 Pantoea agglomerans를 alginate, agar 및 gelatin에 고정화시킨 후 tricalcium phosphate가 첨가된 액체 배지에서 배양하여 인산가용화능을 비교하였으며, 또한 alginate에 고정화된 균에 의한 인산가용화능을 경시적으로 조사하였다. 고정화를 위한 담체로 alginate나 agar를 사용하였을 때, 고정화된 P. agglomerans의 인산가용화능이 gelatin을 담체로 사용하였을 때보다 우수하였다. Alginate에 고정된 P. agglomerans가 접종된 처리구에는 배양 후 5일까지 유효인산의 농도가 크게 증가하였고 모든 처리 구에서 배지 안의 pH가 감소하였다.

• 한국산학기술학회논문지
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• 제8권1호
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• pp.136-142
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• 2007

최근 부영양화를 야기시키는 물질인 $PO_4^{3-}$ 이온을 제거하기 위해 고형반응물을 이용하는 것이 주목을 받고있다. 철광석의 정련 과정에서 생기는 슬래그는 용해된 무기 인산염을 폐수로부터 유리시켜 흡착 제거하는 것에 대한 근본적인 연구가 이루어져 왔다. 본 연구는 물 속의 인산염을 제거하기 위해 전로슬래그를 이용하였을 때 오랜 시간동안 hydroxyapatite 형태로 변화시켜 제거하고 인산염 제거를 향상시키기 위한 가능성을 찾기 위하여 여러 가지 조건을 변화시켜서 수행하였다. 본 연구 결과 전로슬래그를 이용한 등온흡착식을 적용했을 때 Freundlich 식을 적용할 수 있었으며, 인을 제거하는데 사용된 전로 슬래그의 크기는 $2{\sim}0.425mm$가 가장 적당한 것으로 나타났다. 특히, 연속반응탑을 이용할 경우, 유입수 농도가 1 mg/L일 때 80%까지 제거되는 것으로 나타났다.

• 상하수도학회지
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• 제26권6호
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• pp.841-849
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• 2012

The effluent quality of phosphorus is strengthened by the national standard to conserve water resources to lessen the eutrophication threat. The soluble phosphate in the wastewater effluent can be removed using the converter slag as solid waste produced through the steel making process. The experiments for removal efficiencies and removal constants were performed for this research with the artificial wastewater following several different conditions, particle size, phosphate concentration and initial pH. The correlation coefficients of Freundlich adsorption isothem were 0.9505 for $PS_A$, 0.9183 for $PS_B$, respectively. The removal efficiency was 87-94 % for $PS_A$ and 90-96 % for $PS_B$ respectively. The pH of the wastewater was elevated to pH 11.8 for the initial pH 8.5, phosphate removal efficiency was the highest as 84 % ~ 98 %. In case of 10 mg/L of the intial phosphate, the removal efficiency was 96 ~ 98 %. The more initial pH increases, the higher the reaction rate constant is.

• 한국표면공학회지
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• 제52권4호
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• pp.233-238
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• 2019

The formation behavior of zinc phosphate conversion coating (ZPCC) on SCM430 alloy was investigated in 25 vol.% of 1M ZnO + 170 ml/L solution containing various $Fe(NO_3)_2$ concentrations, using open-circuit potential(OCP), electrochemical impedance spectroscopy(EIS), cyclic polarization(CP) curve and tape peel test. OCP of SCM430 alloy and corrosion current density increased with increasing $Fe(NO_3)_3$ concentration. Resistance of films formed on SCM430 alloy by chemical conversion treatment decreased with increasing $Fe(NO_3)_3$ concentration. Color and adhesion of chemical conversion coatings became darker and worse, respectively, with increasing $Fe(NO_3)_3$ concentration. It is concluded that addition of $Fe(NO_3)_3$ into a zinc phosphating bath leads to faster reaction to form porous surface coatings with poor adhesion and corrosion resistance.