• 한국생물공학회:학술대회논문집
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• 2000.04a
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• pp.207-210
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• 2000

Pseudomonas oleovorans was cultivated to produce medium chain length polyhydroxyalkanoates (MCL-PHA) fram octanoic acid and ammonium nitrate as carbon and nitrogen source, respectively, by a pH-stat fed-batch culture technique. The octanoate concentration of the culture broth was maintained below 4 g/L by feeding the mixture of octanoic acid and ammonium nitrate when the culture pH rose above high limit. The effect of the ratio of octanoic acid to ammonium nitrate (C/N ratio) in the feed on the PHA production was examined. The final cell concentrations of 62.5, 54.7, and 9.5 g/L, PHA contents of 62.9, 75.1, and 67.6% of dry cell weight, and productivities of 1.03, 0.632, and 0.161 g/L/h were obtained when the C/N ratio in the feed were 10, 20, and 100 g octanoic acid/g ammonium nitrate, respectively.

• Journal of Applied Biological Chemistry
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• v.56 no.3
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• pp.171-177
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• 2013

Efficient extraction of total proteins from soil microorganisms is tedious because of small quantity. In this regard, an improved method for extraction of whole cell proteins is developed from soil microorganisms, Saccharomyces cerevisiae and Pichia pastoris. of which the cell wall are very strong. Pretreatment with NH4OH prior to the final extraction using NaOH/SDS was tried under the basis that ammonium ion was possible to enhance the permeability and/or to weaken the yeast cell walls. The pre-treatment of yeast cells with NH4OH drastically enhanced the protein extraction when it was compared with control (without NH4OH pre-treatment). At the pre-treatment of 0.04 N NH4OH at pH 9.0, about 3 fold of proteins was obtained from p. pastoris. Ammonium hydroxide appears to penetrate into the yeast cell walls more readily at basic pH. The effect of NH4OH pretreatment was pH dependent. The methods developed in this experiment might be applicable for an effective extraction of yeast proteins for the purpose of biochemical studies, especially proteomic analysis.

• Journal of Korean Society on Water Environment
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• v.25 no.5
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• pp.750-757
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• 2009

The ammonium ion exchange characteristics of natural zeolite were investigated to remove ${NH_4}^+-N$. The effect of water temperature, particle size and competitive cation on the exchange capacity was examined. Ammonium ion exchange capacity tended to decrease when the temperature increased from $25^{\circ}C$ to $40^{\circ}C$. Exchange capacity was increased according to the particle size of natural zeolite comes to be small. Batch isotherm experiments were conducted for measuring ammonium ion exchange capacity. The ion exchange capacity was well described either by the Langmuir isotherm model or by the Freundlich isotherm model. The ammonium ion exchange capacity ($q_m$) of zeolite carrier can be calculated $11.744mg-{NH_4}^+/g$-carrier. The ion exchange capacity of manufactured zeolite carrier was showed a similar tendency as ion exchange capacity of powder-sized natural zeolite. Therefore, zeolite carrier can be used for increasing of nitrogen removal efficiency in the wastewater treatment plants.

• KSBB Journal
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• v.11 no.4
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• pp.389-397
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• 1996

The growth of recombinant E. coli and formation of the by-products were investigated. Ammonium phosphate is known to affect the cell growth as well as the enzyme formation. When initial ammonium phosphate concentration was 0.5g/L, cell mass was 4.1g/L. By adding tryptone to the medium, acetic acid formation increased while lactic acid formation decreased. In cultivating recombinant E. coli, lactic acid and acetic acid turned out to be important by-products which affected cell yield and growth rate. Initial ammonium phosphate and tryptone concentration were optimized in our research and can be applied for other culture of recombinant E. coli.

• Korean Journal of Plant Resources
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• v.5 no.1
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• pp.57-68
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• 1992

The effects of various kind and amount of nitrogen fertilizers on the plant grorth. physiological , yield and extracts. ligustilide, butylidene phthalide contents of curdsdrug "Tou-ki" (AnTelica acutiloba Kitagawa) were investigated in 1989. Five plots variouskind of nitrogen fertilizers. Namely, no nitrogen, urea. ammonium nitrate, ammoniumchloride and control plot of ammonium sulfate. The other, by providing five plotsdifferent composed ratio of nitrogenous fertilizers. containing no nitrogen (No. o) .0.5-fold nitrogen (No s), control plot of 1.0-fold nitrogen(Nl.o). 1.5-fold nitrogen(Nl s)and 2.0-fold nitrogen Na. o), but nitogen was used the ammonium sulfate. The results showedthat the crude drug "Tou-ki" can ammonium chloride be produced in good yield, displayingboth good plant growth and remarkable physiologically-active conditions, and it can beproduced such that the extracts is maximized. Additionally, using methods of gaschromatography (GC) , it was established that ligustilide and butylidene phthalide, majorcomponents in the crude drug was recovered in a good yield from the fully grown plants.The other, the plant growth, the physiologically-active, the weight of whole plant, theyield of extracts and ligustilide, butylidene phthalide were seen to be best at the plotof 2.0-fold nitrogen and according to the increase or decrease of nitrogen decreasedgradually. Therefore. about 2 fold of standard quantity seems to be the most suitablequantity of nitrogen for "Tou-ki" cultivation .uot;Tou-ki" cultivation .ion .

• Journal of the Korean Applied Science and Technology
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• v.11 no.2
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• pp.139-146
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• 1994

MDABM and MDAEW, as a accelerating weight loss agents, were prepared by adding water to myristyldimethylbenzylammonium bromide(MDAB) and myristyldimethylethylammonium ethyl sulfate (MDAE) synthesized. As a result of weight loss finishing of the MDABW and MDAEW with NaOH on PET fiber, the ratio of weight loss of MDABW was very larger than that of MDAEW. This result showed that quaternary ammonium bromide had higher weight loss effect than quaternary ammonium sulfate, and the ratio of weight loss was greatly varied with the kind of quaternary ammonium salts used. In these conditions, proper treatment concentration, treatment time, and treatment bath ratio were about 8g/l, $6O{\sim}90min$, and $40:1{\sim}50:1$, respectively.

• Journal of Wetlands Research
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• v.16 no.2
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• pp.275-280
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• 2014

Because ammonia in water body can cause water pollution as a result of generating ammonium ion, it is of importance in the management of water quality. This work performed to analyze the ammonium ion by measuring the color band length on the basis of modifying the indophenol method. When 1-naphthol was employed as a coloring agent, the maximum absorbance was shown near 720nm, where the proper injection was in the range of 0.5-1.5ml. About 80% of absorbance was observed after the color development was made within the 20 minutes. In the manufacturing of coloring agent, the proper concentration of NaOH was 1.5-2.5M, and the effect of pH on the color development is negligible. In addition, the color development was effectively in the region of room temperature.

• Journal of fish pathology
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• v.13 no.2
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• pp.103-110
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• 2000

The immunostimulatory effects of quaternary ammonium compounds(QACs) were investigated in leucocytes of eel(Anguilla japonica) in vitro. Proliferation of peripheral blood lymphocytes(PBLs) was no significantly affected by QACs, regardless of mitogen(PHA, ConA and LPS) and the concentration of QACs added. QACs heightened the leucocytes function such as respiratory burst activity, phagocytosis and pinocytosis, resulting in significantly increased the bactericidal activity of macrophages. These results suggested that QAC might modulate the immune responses by activation of leucocytes function but not by increment of immunocompetent cell numbers.

• Nuclear Engineering and Technology
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• v.49 no.3
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• pp.541-548
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• 2017

Uranium metal used for fabrication of fuel for research reactors in India is generally produced by magnesio-thermic reduction of $UF_4$. Performance of magnesio-thermic reaction and recovery and quality of uranium largely depends on properties of $UF_4$. As ammonium diuranate (ADU) is first product in powder form in the process flow-sheet, properties of $UF_4$ depend on properties of ADU. ADU is generally produced from uranyl nitrate solution (UNS) for natural uranium metal production and from uranyl fluoride solution (UFS) for low enriched uranium metal production. In present paper, ADU has been produced via both the routes. Variation of uranium recovery and crystal structure and composition of ADU with progress in precipitation reaction has been studied with special attention on first appearance of the precipitate Further, ADU produced by two routes have been calcined to $UO_3$, then reduced to $UO_2$ and hydroflorinated to $UF_4$. Effect of two different process routes of ADU precipitation on the characteristics of ADU, $UO_3$, $UO_2$ and $UF_4$ were studied here.

• KSBB Journal
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• v.21 no.6 s.101
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• pp.428-432
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• 2006

This study investigated the effect of sulfate source on removal efficiency in electrokinetic bioremediation which needs sulfate to degrade contaminants by an applied microorganism. The representative contaminant and the applied microorganism were phenanthrene and Sphingomonas sp. 3Y, respectively. When magnesium sulfate was used, the magnesium ion combined with hydroxyl ion electrically-generated at cathode to cause the decrease of electrolyte pH, and then the microbial activity was inhibited by that. When ammonium sulfate and disodium sulfate were used to solve the pH control problem, the pH values of electrolyte and soil solution were maintained neutrally, and also the high microbial activity was observed. With the former sulfate source, however, ammonium retarded the phenanthrene degradation, and so the removal efficiency decreased to 12.0% rather than 21.8% with magnesium sulfate. On the other hand, the latter improved the removal efficiency to 27.2%. This difference of removal efficiency would be outstanding for an elongated treatment period.