• Ocean and Polar Research
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• 제30권3호
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• pp.225-238
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• 2008

In order to investigate the effects of intertidal sediments on the nutrient cycle in coastal environments, the benthic fluxes of ammonium, nitrate, nitrite, phosphate, and silicate at two stations on the intertidal flat of Keunso Bay were determined during each season. The efflux of ammonium was observed at S1 and resulted from the diffusion of remineralized ammonium and acceleration caused by the bioirrigation of macrofauna. The influx of ammonium at S2 was probably due to nitrification in the water column. The influx of nitrate was observed at both stations during all seasons, indicating that the nitrate in the pore water was removed by denitrification. Vigorous bioirrigation led to the efflux of dissolved inorganic nitrogen (DIN) at S1, whereas the influx of DIN at S2 was predominantly caused by denitrification. Contrary to the diffusive and bio-irrigated release of remineralized phosphate from the sediment at S1, the influx of phosphate was observed at S2, which may be attributable to adsorption onto iron oxides in the aerobic sediment layer. Silicate, which is produced by the dissolution of siliceous material, was mostly released from the sediment by molecular diffusion and bioirrigation. However, the influx of silicate was observed at S2 during spring and winter, which was ascribed to adsorption by particulate matter or assimilation by benthic microphytes. The annual fluxes of DIN were 328 mmol $m^{-2}yr^{-1}$ at S1 and -435 mmol $m^{-2}yr^{-1}$ at S2. The annual fluxes of phosphate were negative at both sites (-2.8 mmol $m^{-2}yr^{-1}$ at S1 and -28.9 mmol $m^{-2}yr^{-1}$ at S2), whereas the annual fluxes of silicate were positive at both sites (843 mmol $m^{-2}yr^{-1}$ at S1 and 243 mmol $m^{-2}yr^{-1}$ at S2).

• 한국가구학회지
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• 제19권6호
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• pp.475-486
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• 2008

In this study, fire-retardant chemicals were melt with mixed composition ratios of dibasic ammonium phosphate and each half of boric acid and borax in hot water, in which hammer-milled chips were immersed to increase swelling of waste particleboards. Also, fire-retardant treated particles from sawn lumber chip and recycled particleboard chip were composed in ratio of 70:30 in core layer to improve boards' properties. Retention ratio of fire-retardant chemicals for the particles for face layer was high due to high specific surface area, and that of sawn lumber chips was somewhat higher than that of recycled particleboard chips. The mixture of particles from sawn lumber chips and recycled PB of 70:30 in weight ratio exceeded bending strength of 100 $kgf/cm^2$. It seemed that the relatively greater portions of dibasic ammonium phosphate affected adversely to dimensional stability, however fire-retardants treatment resulted in distinct effect lowering formaldehyde emission such as $E_0$ type(0.5mg/$\ell$ or less) in KS F 3104. In fire-retardancy, the recycled boards with a mixed ratio of dibasic ammonium phosphate to boric acid borax(50:50 mixture) of 70% to 30% in weight satisfied fire-retardancy 3rd grade in KS F 2271, and also this composition from cone calorimeter test met same standard grade figuring total heat release of 4.6MJ/$m^2$.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.170.3-171
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• 2003

An efficient Erythropoietin (EPO)-expression system in mammalian cells is required for massive production for therapeutic use. Ammonium ion is a major problem in the production of valuable recombinant proteins in cultured animal cells. Therefore, it is of importance to devise a system by which a high productivity of human therapeutic recombinant protein can be maintained or enhanced under low ammonium concentration. To reduce the ammonium ion accumulated in EPO producing Chinese Hamster Ovary (CHO) ceels, IBE, we introduced the first two genes of the urea cycle, carbamoyl phosphate synthetase (CPSI) and arnithine transcarbamoylase (OTC), into IBE using a stable transfection method. (omitted)

• Journal of the Korean Wood Science and Technology
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• 제42권2호
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• pp.157-162
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• 2014

This study was conducted to examine the functionality of the fire retardant treated wood. The hygroscopic property, leaching resistance, metal corrosive efficacy and gas toxicity of retardant treated wood were analyzed. Sodium silicate was penetrated to the wood for making fire retardant treated wood. The subsequent treatment agents such as boric acid, ammonium borate, di-ammonium phosphate were treated after sodium silicate treatment due to fixation. As results for the test, the leaching resist was improved by subsequent treatment. The fire retardant combination such as sodium silicate, boric acid and di-ammonium phosphate showed high hygroscopic property, metal corrosive efficacy. The gas toxicity was also satisfied KS standard.

• KSTLE International Journal
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• 제5권2호
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• pp.49-51
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• 2004

The electrical and rheological properties pertaining to the electrorheological (ER) behavior of chitosan derivatives, chitosan, chitosan ammonium salt and chitosan phosphated suspensions in silicone oil were investigated. Chitosan derivative suspensions showed a typical ER response (Bingham flow behavior) upon application of an electric field. However, chitosan phosphate suspension exhibited an excellent shear yield stress compared with chitosan and chitosan ammonium salt suspensions. The difference in behavior results from the difference in the conductivity of the disperse phases due to the difference of their polarizability. The shear stress for the chitosan, chitosan ammonium salt and chitosan phosphate suspensions exhibited a linear dependence on the volume fraction of particles and 1.18, 1.41 and 1.67 powers of the electric field. On athe basis of the experimental results, the newly synthesized chitosan dervative suspensions found to be an ER fluid.

• Journal of the Korean Wood Science and Technology
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• 제12권2호
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• pp.10-19
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• 1984

The $3{\times}3{\times}30$ ($cm^3$) sized lumbers of Populus alba-grandulosa L. were treated with four fire-retardant solutions of ammonium sulfate, monoammonium phosphate, diammonium phosphate and aluminium chloride for 1, 15, 30, and 60 minutes and 1, 3, and 7 days. Thereafter they were air-dried and burned at high temperature about $1,800^{\circ}C$ and for short time of five minutes. This study estimated the relationship between absorbed chemical amounts and rate of weight loss or residual bending strength of these burned lumbers. The results were as follows: 1) In absorption amount of fire-retardant chemicals, diammonium phosphate showed the largest, aluminium chloride the smallest, but monoammonium phosphate and ammonium sulfate showed similar level. 2) The absorption amount of chemicals was decreased with the increase of specific gravity in the same species except aluminium chloride. 3) The rate of weight loss was decreased as the absorption amount of chemicals increased, especially monoammonium phosphate was most effective. 4) The MOR value of the residual bending strength was increased as the absorption amount of chemicals increased and especially monoammonium phosphate showed the most efficient effect. 5) Aluminium chloride showed more striking increase of MOR value of residual bending strength with the increase of absorption amount than any other chemical, therefore its MOR value was similar to the maximum MOR value of the most effective monoammonium phosphate. 6) The correlation between weight loss and MOR value of the residual bending strength was negative and aluminium chloride showed the most striking negative relation, but the others showed similar trends. 7) The correlation between work to proportional limit and absorption amount of chemicals was positive and the degree of increase in work to proportional limit was most in aluminium chloride, and the next, in monoammonium phosphate and diammonium phosphate in turn. 8) The correlation between work to maximum load and absorption amount of chemicals showed positive and diammonium phosphate revealed the best result and aluminium chloride showed better results than other two chemicals.

• Asian-Australasian Journal of Animal Sciences
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• 제32권4호
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• pp.527-532
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• 2019

Objective: Phosphorous (P) sources with greater bioavailability might increase animal production efficiency and decrease environmental pollution. The objective of current study was to determine animal performance, nutrient digestibility, blood metabolites and fecal P concentration in finishing lambs fed a diet with either di-calcium phosphate (DCP) or di-ammonium phosphate (DAP) as a P source. Methods: Twelve 4-month-old male lambs (initial body weight $24.87{\pm}3.4kg$) were randomly allocated to a diet with either DCP or DAP (~261 g/kg of total diet P) fed ad libitum for 93 days. Diets were iso-nitrogenous and iso-energetic and had same calcium (Ca) and P concentrations. Results: The DAP contained 19.7 g/kg of dry matter (DM) Ca, 185.4 g/kg DM P and 14,623 ppm fluorine, while DCP contained 230.3 g/kg DM Ca, 195.2 g/kg DM P and 1,039 ppm fluorine. The diet with DAP contained 60 ppm fluorine while the diet with DCP contained 13 ppm fluorine. Lambs fed the diet with DAP tended to have a greater daily DM intake compared to those fed diet with DCP (p = 0.09). Lambs fed DAP had greater plasma P concentration and alkaline phosphatase activity ($p{\leq}0.01$) compared with lambs fed DCP. Dry matter and organic matter digestibility of the diets were similar between two treatments at days 60 and 90, while they were greater in lambs fed DCP (p<0.05) at day 30 of the trial. Feeding DAP increased P digestibility (58.7% vs 50.2%; p<0.05) and decreased fecal P concentration in lambs compared with feeding DCP (3.1 vs 3.8 g/kg DM; p<0.05). Conclusion: Providing ~261 g/kg of total diet P as DAP in the diet of finishing lambs improved the bioavailability of P in the body and decreased excretion of P in feces without affecting lamb performance.

• 한국물환경학회지
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• 제31권4호
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• pp.387-391
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• 2015

This study was performed to evaluate the effect of pH (8-12) and molar ratio of magnesium and phosphate ($[Mg^{2+}]/[PO_4{^{3-}}]$) (0.6-1.4) on struvite crystallization of anaerobic digester supernatant using seawater as magnesium source. pH range of 9-10 is favorable for ammonium and phosphate recoveries. The recovery efficiency of ammonium was highest at $[Mg^{2+}]/[PO_4{^{3-}}]$ of 1.0 and pH 10. On the other hand, high phosphate recovery efficiency (> 99%) was achieved at ($[Mg^{2+}]/[PO_4{^{3-}}]$) of 1.4 and pH 10. The results demonstrated that seawater can be considered as low-cost magnesium source to recover phosphorus from anaerobic digester supernatant.

• KSBB Journal
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• 제18권3호
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• pp.197-201
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• 2003

알콜증류 폐액에 빵효모를 배양하는 중에 포도당, 암모늄 및 인산을 자동 첨가하여 균체량을 효율적으로 증가시킴으로써 폐액의 재이용성을 향상시키고자 하였다. 포도당은 DO를 제어파라미터로 하는 제어방법을 사용하여 자동 첨가함으로서 그 농도를 300 mg/L 이하로 유지하였다. 암모늄은 pH-stat 방법을 사용하여 N $H_4$OH로서 자동 첨가함으로서 12.6~17.4mM의 낮은 농도범위로 유지하였다. 인산의 경우에는 분석방법으로써 ascorbic acid법을 채택한 자동화 FIA sysetm을 제작하여 사용하였다. 이 system으로 배양 19.4 시간 후부터 배양액을 자동분석하고 제어한 결과 배양액의 P $O_4$-P 농도를 23.3~43.4 mg/L 의 낮은 농도범위로 유지할 수 있었다. 세가지 영양성분을 자동첨가하면서 배양한 결과 증식의 정체없이 균체량을 33.0배 더 증가시킬 수 있었다. 비증식속도는 0.19 $hr^{－l}$였다.

• Applied Biological Chemistry
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• 제38권4호
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• pp.308-312
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• 1995

주목 (Taxus cuspidata) 세포배양을 이용하여 modified B5 배지중의 질소원, 인산 그리고 세포 고정화가 세포생장과 taxol 생산에 미치는 영향을 살펴보았다. Nitrate와 ammonium의 비는 세포생장 및 taxol 생산에 있어 중요한 인자임을 알수 있었고 비값이 1인 경우는 modified B5 배지 조성중 원래 비값인 20에 비해 taxol 생산을 10배나 증가시켰다. 인산의 농도를 감소시킨 경우 세포생장은 저하되었지만 taxol 생산은 현저하게 증가하였다. 고정화세포는 ${\sim}120\;g/l$의 taxol을 생산하였다.