• Membrane and Water Treatment
• /
• 제3권2호
• /
• pp.133-140
• /
• 2012

The overall performance of BNR-MBR, so-called Anoxic-Anaerobic-Aerobic Membrane Bioreactor ($A^3$-MBR), developed for nutrient removal was studied to determine the efficiencies and mechanisms under different solid retention time (SRT). The reactor was fed by synthetic high-rise building wastewater with a COD:N:P ratio of 100:10:2.5. The results showed that TKN, TN and phosphorus removal by the system was higher than 95%, 93% and 80%, respectively. Nitrogen removal in the system was related to the simultaneous nitrification-denitrification (SND) reaction which removed all nitrogen forms in aerobic condition. SND reaction in the system occurred because of the large floc size formation. Phosphorus removal in the system related to the high phosphorus content in bacterial cells and the little effects of nitrate nitrogen on phosphorus release in the anaerobic condition. Therefore, high quality of treated effluent could be achieved with the $A^3$-MBR system for various water reuse purposes.

• 농업과학연구
• /
• 제50권4호
• /
• pp.653-661
• /
• 2023

Phytase enhances phosphorus availability in pig diets by breaking down phytic acid, which is challenging for animals to digest. This study aimed to assess the impact of dietary phytase supplementation on the growth performance, nutrient digestibility, and fecal score of growing pigs. Sixty-four growing pigs ([Yorkshire × Landrace] × Duroc, average body weight 21.20 ± 0.18 kg) were randomly assigned to one of two treatment groups. The dietary treatments were CON, basal diet, and PHY, basal diet + 0.0025% phytase. Results indicated a tendency for increased average daily gain in the phytase-supplemented diet group (p < 0.10) compared to the control diet group. The average daily feed intake and feed conversion ratio were not affected by the addition of 0.0025% phytase. Furthermore, dry matter digestibility, nitrogen content, and digestible energy were not influenced (p > 0.05) by phytase supplementation. Fecal score remained similar (p > 0.05) in growing pigs fed phytase-supplemented and control diets. These findings suggest that supplementing the diet of growing pigs with 0.0025% phytase may lead to improved average daily gain without adverse effects on nutrient digestibility and fecal score. This implies the potential to enhance growth performance without compromising overall health or digestion in pigs. Further investigations into the optimal levels of phytase supplementation for growing pigs are recommended.

• 한국환경과학회지
• /
• 제13권10호
• /
• pp.911-919
• /
• 2004

The purpose of this research was evaluated economical effect to apply alternative external carbon source. Conventional activated sludge process in municipal wastewater treatment plant was adapted and introduced to Biological nutrient removal processes to meet the newly enforced effluent quality standard for nutrient removal in Korea. Low $COD/NH_4^+-N$ ratio and higher nutrient concentration of influent characteristics force to inject external carbon source for denitrifying recycled nitrate. In the most case, methanol was used as external carbon source. But Methanol is expensive and very dangerous in handling. So we could find cheaper and safer external carbon source substituted methanol in last study. This alternative external carbon source is named RCS(recoverd carbon source) and a by-product of fine chemical product at chemical plant. When RCS was applied real municipal wastewater treatment plant, average $55\~65\%$ of T-N removal efficiency, 8.8mg/l of effluent T-N concentration, 11.3mg/l of effleunt COD concentration were obtained without effluent COD increase as against used methanol. To apply RCS in municipal wastewater treatment plant obtain approximately $\74.5%$ expenditure cost reduction in comparison with methanol dosage cost.

• 원예과학기술지
• /
• 제18권1호
• /
• pp.14-17
• /
• 2000

개미취, 감국, 털머위의 양액재배시 질소원의 종류별 생육특성을 조사하기 위하여 배양액의 질소를 $NH_4-N$과 $NO_3-N$ 단용, $NH_4-N$와 $NO_3-N$을 1:1로 혼용하여 처리하였다. 털머위는 $NH_4-N$와 $NO_3-N$의 혼용처리와 $NO_3-N$ 단용처리에서 생육이 우수하고 생체중도 높았다. 개미취와 감국은 $NO_3-N$ 단용 처리에서 생육이 양호하였고, 지상부와 지하부의 생체중이 증가하였다. 질산환원효소(NR) 활성은 세 작물 모두 $NO_3-N$ 단용 처리에서 높았으며, 식물체내 엽록소와 질산염의 함량도 $NO_3-N$ 처리구에서 높았다.

• 한국토양비료학회지
• /
• 제43권5호
• /
• pp.610-615
• /
• 2010

시설 하우스 토마토재배에서 돈분뇨 액비와 화학비료의 관비 처리 효과를 알아보기 위하여 무비, 질소 기준으로 돈분뇨 액비 26 mg $L^{-1}$, 52 mg $L^{-1}$ 및 화학비료 52 mg $L^{-1}$ 4처리를 하여 토마토 수량, 생육, 무기성분함량, 양분흡수량, 양분이용률 및 토양 화학성에 미치는 영향을 알아보았다. 돈분뇨 액비와 화학비료 관비 처리는 수량과 생육에 차이가 없었으며 돈분뇨 액비 26 mg $L^{-1}$ 처리에서 수량이 감소하는 경향을 보였다. 돈분뇨 액비와 화학비료 처리에 비해 잎과 뿌리의 질소와 칼륨함량은 무비에서 낮았으나 뿌리와 줄기의 인산함량은 무비에서 높았다. 칼슘함량은 잎에서 처리간에 차이가 없었으나 뿌리와 줄기는 돈분뇨 액비 52 mg $L^{-1}$ 처리가 높았고 과실내 칼슘함량은 화학비료 52 mg $L^{-1}$ 처리가 낮았다. 양분 이용률은 질소 15.8~6.7%, 인산은 3.0~6.3%, 칼륨은 29.2~43.3%로 칼륨, 질소, 인산 순으로 낮았다. 토양 화학성 중 pH는 돈분뇨 액비 처리가 화학비료 처리보다 높았고 질산태 질소함량은 화학비료 처리가 돈분뇨 액비 처리보다 증가하였다. 치환성 칼륨함 량은 돈분뇨 액비와 화학비료 52 mg $L^{-1}$ 처리구가 높았으며 칼슘과 마그네슘은 처리간에 차이가 없었다. 결과적으로 토마토 관비 재배에서 토양 검정에 의한 돈분뇨 액비 시용은 화학비료 질소와 칼리를 대체하여 이용할 수 있을 것으로 판단되었다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제23권9호
• /
• pp.1213-1220
• /
• 2010

This experiment evaluated the effects of dietary lysine restriction and energy density on growth performance, nutrient digestibility and meat quality of finishing pigs. A $2{\times}2$ factorial arrangement of treatments was utilized in a randomized complete block (RCB) design, and factor 1 was lysine restriction and factor 2 was energy density. The control diet was formulated to contain 3.265 Mcal of ME/kg, 0.75% lysine in the early-finishing phase and 3.265 Mcal of ME/kg, 0.60% lysine in the late-finishing phase and other nutrients met or exceeded NRC (1998) standards. Compared to the control diet (CON), lysine levels of experimental diets were restricted to 15% (treatment EL, EEL) or 30% (treatment ELL, EELL), whereas energy level of experimental diets was increased by 0.100 or 0.200 Mcal of ME/kg. A total of 100 crossbred pigs ([Yorkshire${\times}$Landrace]${\times}$Duroc), with average initial body weight of $58.47{\pm}1.42\;kg$, were allotted to 5 dietary treatments based on sex and body weight. Each treatment had 5 replicates with 4 pigs (two barrows and two gilts) per pen. ADG, ADFI and feed efficiency were calculated in an 8-week growth trial. In the late finishing period (5-8 weeks), pigs fed ELL or EELL diets had decreased ADG and feed efficiency (p<0.01), however, when the EEL diet was provided, a similar growth performance was observed compared to those fed the CON diet during the whole experimental period (p>0.05). In a metabolic trial, 15 pigs were used to evaluate the effect of dietary lysine restriction and energy density on nutrient digestibility. The digestibility of dry matter, crude fat and crude ash was not improved by restricting dietary lysine or energy density. However, crude protein digestibility was decreased (p<0.05) as dietary lysine was restricted. When dietary lysine was restricted, fecal nitrogen was increased whereas nitrogen retention was decreased. BUN concentration was affected by dietary lysine restriction; treatments ELL and EELL had higher BUN values than other treatments (p<0.01). Carcass characteristics and meat quality were measured when average body weight of pigs reached $107.83{\pm}1.50\;kg$. Treatment ELL had higher last rib backfat depth (p<0.05) than treatment CON, but ELL and EEL did not differ significantly. The ELL and EEL treatments had higher (p<0.05) subjective marbling score than treatment CON. Treatment EEL showed higher longissimus fat content than treatment EL and CON (p<0.01). The results indicated that finishing pigs fed a diet with 15% lysine restriction and 3.465 Mcal of ME/kg energy density had no detrimental effects on growth performance and N utilization, and could achieve substantial increases in marbling and longissimus fat content of pork.

• 한국물환경학회지
• /
• 제28권4호
• /
• pp.551-560
• /
• 2012

The objectives of this study were to elucidate spatio-temporal heterogeneity of water chemistry and develop empirical models using trophic variables in Daechung Reservoir during 2005-2010 along with in situ tests of nutrient enrichment bioassays (NEB). The relations of water quality parameters in regard to precipitation showed that seasonal and interannual fluctuations of biological oxygen demand (BOD), total nitrogen (TN) and pH were minor, whereas conductivity, suspended solids (SS), and total phosphorus (TP) were largely varied in response to the magnitude of rainfall. The CHL maxima occurred immediately after the spate of TP during the high flow, indicating that phytoplankton growth was directly controlled by phosphorus. Empirical linear models of CHL-TP indicated that the variation of CHL in premonsoon was accounted 60% ($R^2$ = 0.60, p < 0.05, n = 54) by TP. In the mean time, empirical models of annual CHL-TN showed that the variation of CHL was weakly accounted ($R^2$ = 0.16, p < 0.001) by TN and more strongly ($R^2$ = 0.44, p < 0.001) by TP. Thus, the variation of CHL was more explained by the variation of TP than TN. In situ tests of Nutrient Enrichment Bioassays (NEBs) showed that the growth of CHL was greater in the P-treatments (as $PO_4-P$) than the control and N-treatment (as $NO_3-P$). Overall, our results suggest that phosphorus was aprimary limiting nutrient controlling the seasonal phytoplankton growth, based on the in situ experiments of NEBs.

• 동아시아식생활학회지
• /
• 제15권3호
• /
• pp.271-282
• /
• 2005

This study analyzed the physical indices, food habits and nutrient intakes of patients with hypertension, to provide better research data for the prevention and the cure for disease as well as basic data for nutrition education. The subjects were 44 patients who visited the general hospital, located in Daegu, to receive hypertension treatment The lifestyle, food habit, nutrient intakes, anthropometric measurements, body fat and blood pressure were measured as main indices. By the BMI, $72.8\%$ of the patients were over weight or obesity $(>23\;kg/m^2)$. In the male group, the WHR tended to increase according to the BMI (p<0.05). In the female group, the body fat tended to increase according to the BMI (p<0.05). The group with more monthly income showed lower systolic blood pressure than the group with smaller monthly income (p<0.05). The scores about food habits concerning balanced diet and preference for salt were low, which implied that food habits of subjects were not desirable. The intakes of riboflavin and calcium didn't meet the RDA requirements. Especially, the lack of calcium was more ap~nt in the female patients than the male ones. Despite this, they had more than enough protein, vitamin C, and iron. The physical indices according to blood pressure revealed that the group of higher blood pressure showed greater WHR (p<0.001). The male group with higher systolic blood pressure showed greater BMI than one with lower systolic blood pressure (p<0.05). As for nutrient intakes according to blood pressure, the group with higher blood pressure had more sodium and iron than one with lower blood pressure (p<0.05). The patients with hypertension tended to be more overweight or obese, preferred salty foods, and were in an unbalanced state of nutrient intakes. Thus more systematic and ongoing measures should be pursued to take care of patients with hypertension.

• 원예과학기술지
• /
• 제31권4호
• /
• pp.423-428
• /
• 2013

Although closed soilless culture is useful for saving water and fertilizers with minimizing environmental pollution, adequate management of nutrient solutions is still not stabilized in greenhouse cultivation. In order to investigate the problems occurred in closed soilless culture of Paprika (Capsicum annuum L., cv. Fiesta), we compared ion balance, fruit yield, and the water and fertilizer use efficiencies in the closed system with those in the open system. The plants were grown in rockwool culture with a nutrient solution of EC $2.5dS{\cdot}m^{-1}$. After 4 weeks of treatment, individual ratio of $NO{_3}^-$, $K^+$, $Ca^{2+}$, and $Mg^{2+}$ to total ion concentrations ($meq{\cdot}L^{-1}$) decreased from the initial value, especially the biggest decrement was observed in $K^+$, and on the other hand, $SO{_4}^{2-}$, $Cl^-$, and $Na^+$ were accumulated in the closed system. Yields after four-time harvests were 19% higher in the open system than in the closed system. Total volume of water used per unit area ($m^2$) in the open system was 20% higher, but the total water use per fruit was not significantly different between the two systems, while t total fertilizer use per fruit was 78% higher in the closed system. Amount of marketable fruits was not significantly different between the two systems. We concluded that the increase in $K^+$ supply and the replenishment of recycled nutrient solution every four weeks were required for preventing the imbalance or depletion of nutrients in the close soilless culture of paprika plants to get more balanced nutrient composition during whole cultivation period.

• 한국식품영양학회지
• /
• 제26권4호
• /
• pp.909-918
• /
• 2013

The objective of this study is to investigate the effects of dietary nutrient intakes for markers of blood glucose and inflammation which is important to the progress of type 2 diabetes and the development of its complications. For this study, 76 adults with diabetes (42 males, 34 females) were recruited from a group of patients who had visited the department of endocrine medicine. Data on anthropometric characteristics, clinical indices such as hemoglobin A1c (HbA1c) and C-reactive protein (CRP), and dietary nutrient intakes were collected. Our results have shown that 66% of subjects were either overweight or obese. Serum analysis indicates that levels of C-peptide, glucose, HbA1c, CRP, triglyceride, LDL-cholesterol were higher than normal range. Results from the dietary nutrient intake survey displayed that intakes of cholesterol and sodium were higher than Dietary Reference Intakes for Koreans. On the contrary, folate intake was lower than the guideline. Within the females, energy contribution from carbohydrate was higher than Korean Diabetes Association guideline. Statistical analysis has revealed a negative correlation between serum HbA1c level and dietary intakes of polyunsaturated fatty acid (PUFA), n-3 PUFA, ${\beta}$-carotene and vitamin E after adjustments for age, BMI, smoking habits, alcohol consumption, exercise and ingestion of diabetes mellitus medication (p<0.05). Serum CRP level was inversely associated with dietary intakes of carbohydrate, protein, vitamin C and fiber (p<0.05). Our results suggest that dietary nutrient intakes may influence the levels of HbA1c and CRP, and subsequently, it may help in the management/treatment of type 2 diabetes.