• Journal of Korean Society on Water Environment
• /
• v.26 no.3
• /
• pp.468-473
• /
• 2010

The purpose of this study is to derive the correlation between the Specific Phosphorus Release Rate (SPRR), Specific Phosphorus Uptake Rate (SPUR) and Specific Oxygen Uptake Rate (SOUR) at various Sludge Retention Time (SRT) condition in the A/O process. The laboratory scale reactor was operated on various SRT (10 day, 20 day, 30 day, 40 day). In this study, the SPRR, SPUR and SOUR tended to decrease with the SRT increase. Empirical equations was be obtained $y=4.54E-006x^2+0.0007x-0.0315$, $R^2=0.925$ (SOUR vs. SPRR) and $y=3.22E-006x^2+0.0004x-0.0173$, $R^2=0.928$ (SOUR vs. SPUR) from the relationship between SRT, SPRR and SPUR and SOUR. Therefore, the anaerobic tank design based on the research result such as SPRR, SPUR of a phosphorus design and SOUR would be possible.

• Environmental Engineering Research
• /
• v.19 no.2
• /
• pp.175-184
• /
• 2014

Weirs are conventional structures that control water level and velocity in streams to facilitate water resource management. Despite many weirs built in streams, there is little information how weirs change hydrology regime and how that translates to sediment and phosphorus (P) responses. This study evaluated the influence of weirs on P retention and mobilization in an urban tributary of the Han River in Korea. Total P concentrations in sediments upstream of weirs were higher than the downstream site, mainly due to the increase of potentially available fractions (labile P and aluminum- and iron-bound P) (p < 0.05). Equilibrium phosphorus concentrations ($EPC_o$) were lower than soluble reactive phosphorus (SRP) concentrations of stream waters, but there was an increasing trend of sediment $EPC_o$ upstream of weirs compared to the downstream site (p < 0.001) indicating a greater potential for P release upstream of weirs. Sediment core incubation showed that SRP release rates upstream of weirs were higher than the downstream site under anoxic conditions of the water column (p < 0.01), but not under oxic conditions. SRP release rates under anoxic conditions were greater than that measured under oxic conditions. Un-neutral pH and increased temperature could also enhance SRP release rates upstream of weirs. We conclude that weirs can increase P retention within stream sediments and potentially promote significant P releases into waters, which in turn cause eutrophication.

• Korean Journal of Poultry Science
• /
• v.27 no.1
• /
• pp.19-23
• /
• 2000

The effects of microbial phutase on laying performance and phosphorus utilization were examined at different levels of dietary nonphosphorus(NPP) in 320 23-week-old Hy-line brown hens for 12weeks. Diets were formulated 0.275%(T1), 0.220%(T2), 0.165%(T3) of NPP levels, and supplemental microbial phytase was 300DPU/kg diet constantly. Conventional diet(C) was formulated 0.275% NPP level without microbial phytase. Egg production and egg mass were higher in T2 than the others (p<0.05), and average egg weight was higher in T1 than the other (p<0.05). Egg productivity was tended to increase with supplemental phytase compared to conventional diet. Daily feed intake a hen also increased in T2 (p<0.05). Feed conversion ratio was improved slightly without significant difference. Eggshell breaking strength and thickness were not different significantly among the treatments. Haugh unit and yolk color were also not different. Calcium and phosphorus retention in body increased in T2 (p<0.05), but dry matter and nitrogen retention were not different significantly. Differences in nitrogen and calcium excretions were not found among the treatments. But phosphorus excretion decreased in order of dietary phosphorus levels with supplement phytase compared to C (p<0.05). Tibial ash, calcium and phosphorus were similar among the treatments. In conclusion, supplemental microbial phytase in laying diet may help to utilize phytase phosphorus, and could decrease NPP intake.

• Journal of Environmental Health Sciences
• /
• v.38 no.6
• /
• pp.568-574
• /
• 2012

Objectives: The purpose of this experiment is to understand the phosphorus removal ratio effects of iron plates per unit of surface area through the iron electrolysis system, which consists of an anoxic basin, aerobic basin, and iron precipitation apparatus. Methods: Iron electrolysis, which uses an iron precipitation reactor in anoxic and oxic basins, consisted of iron plates with total areas of 400 $cm^2$, 300 $cm^2$ and 200 $cm^2$ respectively. The FNR process was operated with a hydraulic retention time and a sludge retention time of 12 hours and three days, respectively. Wastewater used in the experiments was prepared by dissolving $KH_2PO_4$ in influent water. Results: The iron plates 400 $cm^2$ (16.6 $mA/cm^2$), 300 $cm^2$ (13.3 $mA/cm^2$) and 200 $cm^2$ (7.3 $mA/cm^2$) in surface area in the phosphorus reactor had respective phosphorus of 2.4 mg/l, 2.7 mg/l and 3.2 mg/l in the effluent and phosphorus removal respective efficiencies of 90.3%, 89.1% and 87.1%. The effluent in the reactor, where the iron plate was not used, had relatively very low phosphorus removal efficiency showing phosphorus concentration of 15.3 mg/l and a phosphorus removal efficiency about 38.3%. Phosphorus removal per ferrous was 0.472 mgP/mgFe in the iron electrolysis system where the surface area of iron was low. Phosphorus pollution load per active surface area and the phosphorus removal efficiency had an interrelation of RE = -0.27LS + 89.0 (r = 0.85). Conclusion: With larger iron plate surface area, the elution of iron concentration and phosphorus removal efficiency was higher. The removal efficiency of phosphorus has decreased by increasing the initial phosphate concentration in the iron electrodes. This shows a tendency of decreasing phosphorus removal efficiency because of decreasing of iron deposition as the phosphorus pollution load per active surface area increases.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.5
• /
• pp.720-726
• /
• 2006

In an attempt to develop an artificial diet for growing olive flounder (Paralichthys olivaceus), weight gain, feed utilization and nutrient retention were investigated in fish fed moist (MP), semi-moist (SMP) and extruded pellets (EP). Excretion of nitrogen and phosphorus was also estimated based on their whole body gain and intake. EP and MP composed of raw fish and SMP made of formulated powder feed with water were prepared to have the same energy contents on a dry matter basis. A total of 240 fish with an average initial weight of 120 g were randomly distributed to each (20 fish/tank) of 12 circular plastic tanks (4 tanks/treatment) and fed experimental diets for 8 weeks. Fish groups fed EP (209 g) or SMP (209 g) recorded higher final weight than those fed MP (176 g), while dry feed consumption was highest in SMP groups (106 g), followed by MP (71 g) and EP groups (62 g). As a consequence, fish groups fed EP showed much lower feed conversion ratio than the other two groups. Protein efficiency ratio was also significantly higher in fish groups fed EP (2.55) than in those fed MP (1.44) and SMP (1.31). Fish groups fed EP, which showed the highest nitrogen retention of 43.9%, resulted in the lowest excretion of nitrogen of 35.5 g per kg gain. Also, the lowest phosphorus excretion of 6.0 g per kg gain was found in the EP groups with the highest P retention (37.0%) among treatments. Although the EP groups had the lowest dietary energy intake, they retained the highest energy in the whole body among treatments. The present results showed that EP could be more advantageous than MP or SMP in terms of growth, feed utilization and excretion of nitrogen and phosphorus for olive flounder.

• Journal of Nutrition and Health
• /
• v.34 no.4
• /
• pp.433-439
• /
• 2001

Intakes and excretions of calcium and phosphorus were determined for 8 female adolescents(aged 16.3$\pm$0.5y; body mass index 20.4$\pm$1.3kg/$m^2$; body fat 33.3$\pm$2.5%; bone mineral density of lumbar spine in L2-L4; 0.96$\pm$0.08g/$\textrm{cm}^2$) when they consumed diets basal and high in calcium for 6 days each. All subjects consumed a basal Ca diet containing 800mg, Korean RDA level of the subjects, and a high Ca diet containing 1200mg, RDA plus 2 SDs of calcium intake. The diets provided 58% of energy intake as carbohydrate, 25% as fat, and 17% as protein. Food, urine, and fecal composites were collected during the last 3 days of each feeding period. Fecal excretion of calcium was significantly greater on the high Ca than on the basal Ca diet. Hence, apparent absorption rate was significantly lowered from 40.9% on the basal Ca diet to 33.1% on the high Ca diet. There was no significant difference in calcium retention between the two diet periods but it tended to be greater on the high Ca diet. However, excretions and retention of phosphorus did not show any significant difference even though intake was significantly increased from 1,253mg on the basal Ca diet to 1,583mg on the high Ca diet. The results indicate that higher calcium intake than the Korean RDA level is recommended for adolescents to meet peak bone mineral accretion and attain a desirable level of calcium retention. (Korean J Nutrition 34(4) : 433~439, 2001)

• Journal of Environmental Health Sciences
• /
• v.26 no.4
• /
• pp.15-20
• /
• 2000

The studies of swine wastewater treatment aim to development of process using soil microorganism. Removal rate of swine wastewater containing organic matter was 99 percent in case of high loading rate. Microorganism was devoted to improve the treatment efficiency of the process. According to the result obtained from biological treatment of high loading rate swine wastewater. Hydraulic retention time was 2.3 days in unit process of biological phosphorus removal. BO $D_{rm}$ / $P_{rm}$ ratio was 1122 in room temperature anaerobic process and 355.6 in mesophilic anaerobic process. And then phosphorus removal rate mesophilic anaerobic process was 3 time as much as than room temperature acaerobic process.

• Asian-Australasian Journal of Animal Sciences
• /
• v.23 no.11
• /
• pp.1490-1495
• /
• 2010

Two experiments were conducted to evaluate the effects of addition of sodium polyacrylate (SPA) to a phytasesupplemented diet on the performance and phosphorus (P) retention of chicks. In experiment 1, chicks were randomly allocated to four dietary treatments which were fed from 7 to 21 days of age: i) basal diet (low nonphytate phosphorus (0.23% NPP)); ii) basal with 250 U/kg diet of phytase; iii) as (ii) with 2.5 g/kg diet of SPA; and iv) as (ii) with 5.0 g/kg diet of SPA. In experiment 2, three replicates, each with three chicks, were fed from 7 to 28 days of age the basal diet (0.23% NPP) with supplementation of phytase (0, 300, 600, 900 U/kg diet) and SPA (0, 2.5 g/kg diet) in a $4{\times}2$ factorial arrangement. In Experiment 1, feed efficiency was improved and excreted P was 10% less with phytase supplementation. However, the addition of SPA did not affect performance or P excretion. Dietary SPA supplementation to the diets showed significantly higher amounts of P retention, and highest values were observed in chicks fed 2.5 g/kg of the SPA-supplemented diet. In Experiment 2, feed efficiency was improved with phytase supplementation, and the addition of SPA showed significant improvement in feed efficiency. Excreted P was significantly lower in chicks fed SPA-supplemented diets, and the retained P coefficient improved with SPA supplementation. In conclusion, the increased transit time of digesta with suitable supplementation levels of SPA may allow phytase activity to be more effective in the degradation of phytate, and improve P retention.

• Journal of the Korean Chemical Society
• /
• v.35 no.6
• /
• pp.659-666
• /
• 1991

A systematic analysis of 18 stimulants and narcotic analgesics containing nitrogen atom (s) in human urine by gas chromatography with nitrogen phosphorus detector (GC-NPD), is described. The urinary extract with diethyl ether at pH 8.5 showed good recoveries of the drugs and less interference peaks on GC chromatogram. Retention data were standardized by the calculation of relative retention times using diphenylamine as the internal standard. The relative standard deviations of retention times were less than 0.1% for the within-run analyses. The response factor (RRF) of a drug relative to the internal standard was calculated. RRF decreased with increasing number of nitrogen atoms. This technique can be adapted to various analytical toxicology problems.

• Journal of Nutrition and Health
• /
• v.28 no.11
• /
• pp.1049-1055
• /
• 1995

This study was designed to investigate the effects of calcium supplementation on calcium metabolism in seven healthy college women, aged from 19 to 21 years old. For this purpose, metabolic studies were conducted for two weeks. During the first week, the subjects ate experimental diet which nutrients composition was similar to their usual intake. And during the consecutive second week, they ate the same experimental diet supplemented with 500mg of calcium daily. The results were summarized as follows ; 1) Fecal excretion of calcium increased significantly (P<0.05), but urinary excretion of that did not show any change after supplementary intake of calcium. 2) Mean apparent calcium absorption was 28.5% and retention was 182mg/day when subjects ate the experimental diet without calcium supplementation. Calcium retention was significantly ate the experimental diet without calcium supplementation. Calcium retention was decreased to 24.1% by additional intake of calcium. 3) Phosphorus balance did not show any change after additional intake of calcium. 4) Serum calcium level was also not changed by additional intake of calcium. 5) Serum calcium level increased significantly(P<0.05) but serum phosphorus level did not show any change after additional intake of calcium. The above results showed that supplementation of 500mg calcium daily can be helpful to increase calcium retention as well as the peak bone mass in young women eating usual Korean diets.