• 한국응용과학기술학회지
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• 제20권4호
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• pp.275-282
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• 2003

Aqueous polyurethane dispersion was synthesized using phosphorus compound which received significant attention for the replacement of halogenated flame retardants. In this study, polyols which have phosphorus moity in their structural unit were synthesized by two-step polycondensation reaction using dimethyl phenylphosphonate, ethylene glycols. adipic acid, and 1,4-butanediol. In the next step, polyurethane dispersion was prepared using these polyols, isophorone diisocyanate with dimethyl propionic acid. The particle size of polyurethane latex was reduced from 347 nm to 240 nm with increasing DMPA content. It was observed that the LOI values of prepared coatings increased from 27% to 35% with increasing phosphorus content.

• 한국응용과학기술학회지
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• 제21권1호
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• pp.51-61
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• 2004

Reaction intermediates PCP/BZA (PBI) and tetramethylene bis(orthophosphate) (TBOP) wer synthesized from polycaprolactone (PCP) and benzoic acid (BZA) and from pyrophosphoric acid and 1,4-butanediol, respectively. Benzoic acid modified polyesters containing phosphorus (APTB-5, -10, -15) were synthesized by polycondensation of the prepared PBI (containing 5, 10, 15wt% of benzoic acid), TBOP, adipic acid, and 1,4-butanediol. The structure and characteristics of APTBs were examined using FT-IR, NMR, GPC, and TGA analysis. The increase of the amount of BZA in the synthesis of APTBs resulted in decrease in average molecular weight and kinematic viscosity. From the TGA analysis of APTBs, it was found that the afterglow decreased with the amount of BZA content at the high temperatures.

• 한국응용과학기술학회지
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• 제22권2호
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• pp.123-135
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• 2005

Reaction intermediates PCP/BZA (PBI) and tetramethylene bis(orthophosphate)(TBOP) were synthesized from polycaprolactone (PCP) and benzoic acid (BZA) and from pyrophosphoric acid and 1,4-butanediol, respectively. Benzoic acid modified polyesters containing phosphorus (APTB-S, -10, -15) were synthesized by polycondensation of the prepared PBI (containing 5, 10, 15wt% of benzoic acid), TBOP, adipic acid, and 1,4-butanediol. Network structured PU flame-retardant coatings (APHD) were prepared by curing the synthesized benzoic acid modified polyesters containing phosphorus (APT B - 5 , -10, -15) with hexamethylene diisocyanate (HDI)-timer. From the TGA analysis of APTBs, it was found that the afterglow decreased with the amount of BZA content at the high temperatures. With the introduction of BZA, the film viscosity and film hardness of APHD decreased. With the introduction of caprolactone group, the flexibility, impact resistance, accelerated weathering resistance of APTBs increased. Flame retardancy of the coatings was tested. In a vertical burning method, APHD shows 210$^{\sim}$313 seconds, which indicates that the coatings are good flame-retardant coatings. Moreover, the amount of afterglow and flame retardancy of the coatings are decreased with increasing BZA content.

• Journal of Microbiology and Biotechnology
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• 제16권7호
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• pp.999-1009
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• 2006

Physiological, biochemical and genetic studies of Corynebacterium glutamicum, a workhorse of white biotechnology used for amino acid production, led to a waste knowledge mainly about amino acid biosynthetic pathways and the central carbon metabolism of this bacterium. Spurred by the availability of the genome sequence and of genome-based experimental methods such as DNA microarray analysis, research on genetic regulation came into focus. Recent progress on mechanisms of genetic regulation of the carbon, nitrogen, sulfur and phosphorus metabolism in C. glutamicum will be discussed.

• 한국수처리학회지
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• 제26권6호
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• pp.117-124
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• 2018

For the effective removal of phosphorus in water, a novel type of composite was prepared by combining Poly Alumiun Chloride, widely used in sewage/wastewater treatment plants, and Humic Acid particles, which are known to have phosphorus removal ability, with CI. The surface of the ferromagnetic CI particles was oxidized and activated, and then PAC and HA were synthesized to finally produce CIPAC and CIHA. CIPAC and CIHA prepared by this study showed similar results to the phosphorus removal efficiencies of PAC and HA coagulants. The novel composite has a larger weight than the conventional coagulant, and the coagulated sludge precipitates rapidly. The sludge could be easily separated in a short time if the external magnetic field was given by the ferromagnetic force of CIPAC and CIHA prepared with CI as support. Therefore, it can be concluded that if phosphorus removal is carried out using CIPAC and CIHA prepared through this study with external magnetic field, the sedimentation rate will be much faster than that of conventional coagulant. Thus it is possible to obtain a high economic benefit in the sludge recovery part.

• Journal of Plant Biology
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• 제16권1_2호
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• pp.23-29
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• 1973

The effect of phosphorus nutrition on the content of deoxyribonucleic acid(DNA), ribonucleic acid(RNA), crude protein and plant growth of soybean plant(Glycine max, Merr.) was studied. Yields of the above-and under-ground parts of the soybean plant in terms of dry weight, the amounts of crude protein, RNA and DNA continued to increase with increasing phosphorus supply. The amounts of RNA and crude protein were highest in the leaf tissues where most intensive growth was taking place. The relationships among DNA, RNA, crude protein and plant growth appeared to consist of the central dogma which has immortalized, while DNA in plant tissue was subject to charges cuased by external environmental facters such as phosphorus nutrition.

• Asian-Australasian Journal of Animal Sciences
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• 제13권12호
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• pp.1764-1769
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• 2000

The purpose of this experiment was to investigate the antioxidant effect of nitrite on total, neutral, and polar lipids and fatty acid composition in laboratory-cooked ground pork. Muscle samples (Biceps femoris) were analyzed using Iatroscan, gas chromatography, phosphorus content, and TBARS value. The total and neutral lipid contents of muscle were higher in nitrite-untreated meat (0 ppm) than in nitrite-treated meat (100 ppm) but the reverse was observed for polar lipid contents. The results for neutral lipids showed a similar trend when compared with total lipids. Polyunsaturated fatty acids contents of total, neutral and polar lipid in 100 ppm treated meat were higher than that of 0 ppm. The phosphorus content was higher in 100 ppm meat than in 0 ppm but the reverse was observed for TBARS value. These results showed that the addition of 100 ppm nitrite to ground pork resulted in a remarkable antioxidant effect during refrigeration storage.

• Carbon letters
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• 제11권2호
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• pp.112-116
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• 2010

The objective of this study was to evaluate the possibility of simultaneous removal of ammonium, nitrate and phosphorus in water using the zeocarbon. In this study, the surface of zeocarbon was modified by acid because of difficulty in application of water treatment. After surface modification, the strength was enhanced about 62% higher than that of original one. The removal efficiency of ammonium and nitrate using the modified zeocarbon was about 47% and 32%, respectively and were higher than that of zeocarbon. In batch type experiment on the simultaneous removal of ammonium, nitrate and phosphorus, the presence of phosphorus did not have influence on nitrogen removal efficiency. Concomitantly, removal efficiency of phosphorus was obtained was about 35%. This indicates that the surface modified zeocarbon can be applied for simultaneous removal of nitrogen and phosphorus. Consequently, our results could be used as basic data to design of one-stage nitrogen/phosphorus simultaneous removal system.

• ALGAE
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• 제28권1호
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• pp.101-109
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• 2013

Some Chlorella species grow heterotrophically with organic substrate in dark condition. However, heterotrophic Chlorella species are limited and their optimum culture conditions are not fully known. In this study, three heterotrophic Chlorella species, two strains (C4-3 and C4-4) of C. vulgaris and one Chlorella sp. (C4-8) were examined on optimum culture conditions such as carbon source, temperature, and concentrations of nitrogen and phosphorus in Jaworski's medium (JM). And the growth and fatty acid composition of Chlorella were analyzed. For three heterotrophic Chlorella species, glucose (1-2%) as a carbon source only increased the growth and the range of optimum culture temperature was $26-28^{\circ}C$. Doubled concentrations of the nitrogen or phosphorus in JM medium also improved the growth of Chlorella. Chlorella cultured heterotrophically showed significantly higher growth rate and bigger cell size than those autotrophically did. C. vulgaris (C4-3) cultured heterotrophically showed the highest biomass in dry weight ($0.8g\;L^{-1}$) among three species. With respect to fatty acid composition, the contents of C16:0 and n-3 highly unsaturated fatty acid (HUFA) were significantly higher in autotrophic Chlorella than in heterotrophic one and those of total lipid were not different between different concentrations of nitrogen and phosphorus in JM medium. Among three Chlorella species in this study, C. vulgaris (C4-3) appeared to be the most ideal heterotrophic Chlorella species for industrial application since it had a high biomass and lipid content.

• Asian-Australasian Journal of Animal Sciences
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• 제19권2호
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• pp.198-202
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• 2006

An experiment was conducted to investigate the effect of phytase, organic acids and their interaction on body weight gain, feed consumption, feed conversion ratio, carcass yield and tibia ash. A total of 680 three-day old Japanese quail chicks (Coturnix coturnix japonica) were assigned to 20 battery brooders, 34 chicks in each. The experimental period lasted 35 days. The treatment groups employed were: 1) a positive control which included 3.5 g available phosphorus (AP)/kg diet and 10 g Ca/kg diet; 2) a negative control which included 2 g AP/kg diet and 8 g Ca/kg diet, 3) negative control diet supplemented with either 300 FTU phytase/kg diet (phytase) or 4) 2.5 g organic acid (lactic acid+formic acid)/kg diet (organic acid); or 5) 300 FTU phytase/kg diet+2.5 g organic acid/kg diet (phytase+organic acid). All birds were fed with the positive control diet for a week and then transferred to the dietary treatments. At the end of the study, there were no differences (p>0.005) among the groups in body weight, weight gain, feed consumption, feed conversion ratio and carcass yield. Tibia ash, however, was reduced (p<0.001) for quails fed the negative control diet containing a low-level of AP compared to the positive control diet containing adequate AP. The addition of phytase, organic acid or phytase+organic acid to the diets containing the low-level of AP improved (p<0.001) tibia ash. On the other hand, an extra synergistic effect of phytase and organic acid on tibia ash was not determined. This study demonstrated that it may be possible to reduce supplemental level of inorganic P with phytase and/or organic acid supplementation for quail diets without adverse effect on performance and tibia ash.