• Environmental Engineering Research
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• v.17 no.2
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• pp.59-63
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• 2012

This paper proposes a modified Ludzack-Ettinger (MLE) type membrane bioreactor (MBR) as a method of treatment for wastewater from food waste disposer. Micro-membrane filtration allows for an extremely low concentration of suspended solids in the effluent. The effluent of the reactor in question is characterized by a relatively high level of non-biodegradable organics, containing a substantial amount of soluble microbial products and biomass. Results obtained in this paper by measurement of membrane fouling are consistent with biomass concentration in the reactor, as opposed to chemical oxygen demand (COD). The MLE process is shown to be effective for the treatment of wastewater with a high COD/N ratio of 20, resulting in are markedly high total nitrogen removal efficiency. Denitrification could be improved at a higher internal recycle ratio. Despite the low concentration of influent phosphorus, the phosphorus concentration of the outflow is seen to be relatively high. This is because outflow phosphorous concentration is related to COD consumption, and the process operates at along solids retention time.

• Journal of Korean Society of Forest Science
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• v.97 no.3
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• pp.296-304
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• 2008

This study was carried out to analyze vegetation and soil characteristic, and ordination of Stewartia koreana community. The Stewartia koreana community was classified into Acer mono subcommunity, Pinus densiflora subcommunity, Sapium japonicum subcommunity, and Stewartia koreana typical subcommunity. In the study sites, soil organic matter, nitrogen, available phosphorous, exchangeable K, exchangeable Ca, exchangeable Mg concentration, cation exchange capacity, and soil pH were ranged from 14.31~34.27%, 0.33~0.77%, 7.83~22.88(mg/kg), 0.23~1.07(me/100 g), 0.29~2.93(me/100 g), 0.33~1.49(me/100 g), 10.47~22.48(me/100 g), and 4.65~4.96, respectively. The area of the Acer mono subcommunity, found in highlands, showed that contained the highest organic substances, nitrogen, available phosphorous, and cation exchangeable capacity concentration among the communities. The low elevation regions where the Pinus densiflor subcommunity is formed, showed the lowest concentrations of exchangeable Ca, and Mg.

• Journal of the Korean institute of surface engineering
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• v.43 no.2
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• pp.105-110
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• 2010

Electroless nickel plating on porous carbon substrate for the application of MCFC electrodes was investigated. Acidic and alkaline bath were used for the electroless nickel plating. The pore sizes of carbon substrates were 16-20 ${\mu}m$ and over 20 ${\mu}m$. The carbon surface was changed from hydrophobic to hydrophilic after immersing the substrate in an ammonia solution for 40 min at $60^{\circ}C$. The contact angle of water was decreased from $85^{\circ}C$ to less than $20^{\circ}$ after ammonia pretreatment. The deposition rate in the alkaline bath was higher than that in the acidic bath. The deposition rate was increased with increasing pH in both acidic and alkaline bath. The content of phosphorous in nickel deposit was decreased with increasing pH in both acidic and alkaline bath. The contents of phosphorous is low in alkaline bath. The minimum concentration of $PdCl_2$ for the electroless nickel plating was 10 ppm in alkaline bath and 5 ppm in acidic bath. The thickness of nickel was not affected by the concentration of $PdCl_2$.

• Journal of Life Science
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• v.20 no.1
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• pp.49-54
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• 2010

The purpose of this study is to examine the effect of Prunus mume supplementation on changes of energy substrate (glucose, FFA) and fatigue factors (lactate, ammonia, phosphorous) in the performance of exercise. The subjects of this study were 15 male university students. The exercise test was performed for 30 minutes at 75% $VO_2max$ on the treadmill and conducted both before and after administering Prunus mume for 6 weeks. Through Prunus mume supplementation, the accumulation of such fatigue factors as lactate, ammonia, and phosphorous along with concentration of glucuse decreased, but the concentration of FFA increased. From the study, it can be seen that Prunus mume plays a positive role for the use of energy substrates and accumulated fatigue factors.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.527-532
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• 1998

The inflow and outflow loads of T-N and T-P from a paddy field area during the irrigation period were investigated. For the concentration of T-N and T-P, surface water in paddies showed highest among irrigation water, drainage water and percolation water. For T-N, the average concentration of drainage water is higher than that of irrigation water before middle of June but is lower since. It is shown that the L(load)-Q (discharge) equation of T-N has high correlation for irrigation water, but the L-Q equation of T-P has high correlation for drainage water.

• Asian Journal of Atmospheric Environment
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• v.7 no.3
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• pp.169-175
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• 2013

Measurement of the phosphorus concentration in aerosols in Beijing, which was a representative East Asian mega-city, was carried out. The optimum procedure for analyzing phosphorus in aerosols was found in this study. Recovery of phosphorus in environmental samples through the improved method was almost 100%. The concentration of phosphorus in TSP was $145{\pm}47\;ng/m^3$, with a seasonal variation showing high concentrations in winter and low concentrations in summer. The concentrations of phosphorus in $PM_{2.5}$ accounted for $35{\pm}6%$ of those in TSP, with no seasonal variations. The major source of phosphorus in aerosols in Beijing was soil dust, and additional sources of phosphorus in fine particles could be coal combustion and biomass burning.

• Journal of Environmental Health Sciences
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• v.18 no.2
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• pp.62-66
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• 1992

This study was performed to investigate the characteristics of livestock wastewater excepting pig feces and the variation tendency of water quality and the removal efficiency of polluting materials by establishing the sequencing batch reactor in the field.The results were as follows, 1. The characteristics of livestock wastewater as follows: BOD: 619.80, COD$_{cr}$: 782.70, NH$_{3}$-N: 194.20, TKN: 232.81, PO$_{4}$-P: 24.10, T-P: 215.14 (mg/l) 2. During the reaction, negative correlation existed between pH and dissolved oxygen concentration. 3. The removal efficiency of the organic material by the index of BOD and COD was about 90%. 4. Nitrogen removal efficiency was 65.6% by total Kjeldahl nitrogen index, and phosphorous removal efficiency was about 47% by PO$_{4}$-P concentration.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1999.10c
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• pp.670-675
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• 1999

The effect of fertilizer applicatioin on ponded and percolation water in paddies were evaluated at the field plots of the Chungbuk National University for irrigation period. The chemical fertilicers were applied to the study polts at an average application rate of 77, 110, 165kgN/ha, respectively. The concentration of T-N , T-P and COD in ponded water greatly depends on the amount and timing of fertilizer applied. Therefore, the decrease in the amount of fertilizer and proper water management may be needed to decrease in the amount of fertilizer and proper water management may be needed to reduce the runoff loading.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.623-628
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• 2000

This study were conducted to evaluate the mass balance of phosphorus and nitrogen with cropping in experimental pot where the mass of input concentration, and fertilization were variable. Four treatments include CSWNF, TWCF, SWNF. And these cases were compared to the control case of tap water irrigation with conventional fertilization (CONTROL). Fertilization were following conventional fertilization , N : P : K = 11kg : 7kg : 8kg. Input water loading was CSWNF (N:48.7g ,P:3.6g), TWCF(7.8g, 0.6g), SWHF(38.8g ,2.9g), TWNF(38.8g, 2.9g ) and CONTROL(0g ,0g) The result is nitrogen decrease rate; TWCF(19.2%), SWHF(14.9%), CSWNF(9.2%) and SWCF(5.6%). phosphorous decrease rate ; TWCF (10%), SWHF(3.7%), SWCF(0.9%) and CSWNF(0.3%).

• Journal of the Korean institute of surface engineering
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• v.48 no.3
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• pp.100-104
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• 2015

The nickel alloys gets a great deal of attention due to their good mechanical, chemical and magnetic properties. Especially Ni-P alloy systems are very attractive due to their good corrosion resistance and the wear resistance in important technological applications. In this study, the effects of phosphorus acid concentration in plating solution on composition of Ni-P alloy coatings were studied. The Ni-P electrodeposits of the various P contents were investigated in order to understand effect of the composition on mechanical properties of Ni-P electrodeposits. The mechanical properties of electrodeposits increased as the P content in electrodeposits increase. The results of mechanical properties were explained by grain size and P solid solution effect. The effects of heat treatment on mechanical properties of Ni-P alloy coatings were also studied.