• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.861-867
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• 2000

The feasibility of simultaneous phosphorus and nitrogen removal by enhancing anoxic phosphorus uptake was investigated in a sequencing batch reactor (SBR). By introducing an anoxic phase into an anaerobic-aerobic SBR (AO SBR), significant amounts of denitrifying phosphorus accumulating organisms (DPAOs) which can utilize nitrate as electron acceptor could be accumulated in the reactor (anaerobic-aerobic- anoxic-aerobic SBR, $(AO)_2$ SBR). A direct comparison of phosphorus uptake rate under anaerobic and aerobic conditions showed that the fraction of DPAOs in P-removing sludge were increased from 10% in the AO SBR to 64% in $(AO)_2$ SBR. The $(AO)_2$ SBR showed stable phosphorus and nitrogen removal efficiency: average removal efficiencies of TOC, total nitrogen, and phosphorus were 92%, 88%, and 100%. respectively. Results of the $(AO)_2$ SBR operation and batch tests showed that nitrite (up to 10 mg-N/L) was not detrimental to anoxic phosphorus uptake and could serve as good electron acceptor like nitrate.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2010.10a
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• pp.23-23
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• 2010

전북 서해안 새만금 지역에 조성되는 간척지 면적 28,300ha의 30%인 8,400ha 정도가 농업용지로 사용되는 계획이 확정됨에 따라 해당 용지를 효율적으로 사용 할 수 있는 다양한 활용 방안이 요구되고 있다. 대단위 농업지구가 들어설 예정지인 새만금 광활 간척지는 네덜란드와 유사하게 토양의 대부분이 미사질 양토로 이루어져있어 적용 가능한 화훼류를 적절히 선발하고 적합한 재배기술을 도입한다면 대규모 화훼제배 단지로서의 성장 가능성이 충분할 것으로 판단된다. 따라서 전북 농업기술원에서는 2004년부터 7년에 걸쳐 새만금 간척지의 농업적 활용도 제고와 경관농업 육성을 통한 관광자원화 가능성을 확인하기 위하여 72종의 원예작물 적응시험을 실시하였으며 22종의 자생식물과 튤립, 아이리스, 수선화, 히아신스, 참나리 등 5종의 구근 화훼류를 적합 화훼류로 선발하였다. '08~09년에는 내염성과 저온 및 풍해 저항성이 있는 아펠톤, 골든아펠톤, 네그리타, 프랑소와즈, 키스네리스 등을 간척지적용 가능 주요 튤립 품종으로 선발 하였는데 선발된 품종들을 대상으로 높은 염농도 하에서의 체내축적 무기성분을 조사한 결과, K와 Mg은 증가되는 경향이었으나 Ca은 감소되었으며, Cl이온은 현저하게 증가하였다. 또한 튤립체내의 산도 및 전기전도도와 항산화효소의 활성이 증가하였는데 스트레스 반응결과 유해산소가 체내에 축적되고, 이를 중화시키기 위하여 수소이온을 소모함으로써 체내의 산도는 상승된 것으로 추정되며 염분함량이 높을수록 삼투압에 의하여 뿌리에서 흡수는 양분이 적은 반면 잎 줄기의 증산작용은 동일하기 때문에 상대적으로 체내의 농도가 높아져 전기전도도가 상승된 것으로 판단된다. 식물 스트레스의 지표물질로 사용되고 있는 proline 함량도 토양내의 염도가 상승되면서 증가되었으며 엽록소 함량은 감소되는 경향을 보였다.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.3 no.1
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• pp.25-33
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• 1998

Temporal and spatial variations of nutrient elements (ammonia, nitrate, nitrite, phosphate and silicate) in surface seawater off the west coast of Korea were investigated during three periods of field survey aboard R/V Eardo of KORDI (May 1995 and June 1996) and a patrol vessel of the National Maritime Police (November 1995). In general, the concentrations of nutrient elements were lowest in June and highest in November except for ammonia that showed the lowest concentration in May and the highest in November. The results tell us that the development of thermocline and tidal front restricts riverine and benthic supply of nutrient elements to surface waters in June in the offshore regions of the study area which become nutrient-depleted due to phytoplankton bloom in spring. In late fall (November) the level of nutrient concentrations of the surface waters of the study area become high due to vigorous vertical mixing within the water column, which supplies nutrient-enriched bottom water to the surface waters.

• Journal of Chest Surgery
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• v.30 no.8
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• pp.815-818
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• 1997

Prosthetic valve endocarditis(PVE), although uncommon, is associated with significant mortality if the infection spreads into the paravavular structures with later abscess formation. However, combined antibiotic and surgical treatment is often successful. Accurate diagnosis by on echocardiography, effective myocardial protection during operation and increased surgical experience have improved the short-term and long-term outcomes for patients with PVE. A 35-year-old male had a history of replacement of aortic and mitral valve, and tricuspid annuloplasty on August 1994, was admitted due to sudden onset of aphasia, leftward deviation of both eyeballs and spiking fever and diagnosed of having PVE by echocardiography. Reoperation was done after 6weeks of antibiotic treatment. On the operative field, we could notice circumferential vegetation along aortic valve annulus, paravalvular leakage and abscess pocket. The mitral valve amlulus was healthy. The patient underwent redo aortic valve replacement using cryopreserved aortic homograft after radical debridement of infected issue. During the follow up of 7 months period the homograft was well functioning without recurrence of symptoms.

• Analytical Science and Technology
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• v.8 no.1
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• pp.25-32
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• 1995

Determination method of trace thioglycolate has been studied by adsorptive stripping voltammetry. Copper(II)-thioglycolate complex is adsorbed at the hanging mercury drop electrode and stripped during cathodic scan. Electrolyte was used pH 6.5 phosphate and pH 9.5 borate buffer solutions. Optimal conditions were a copper(II) concentration $1{\times}10^{-4}M$, an adsorption accumulation potential -0.2V, an adsorption accumulation time 60 sec and a scan rate 20mV/sec. A detection limit of $1{\times}10^{-9}M$ thioglycolate was obtained. The method was applied to the determination of thioglycolate in cold wave fluids and depilating creams.

• 한국해양학회지
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• v.25 no.1
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• pp.8-20
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• 1990

A series of pore water data were obtained during the different time over one year period between October 1987 and October 1988, from a site on a muddy intertidal flat, located in the Kyeong-gi Bay, west coast of Korea, The results have revealed that the tidal flat is an environment of active nutrient the subface supplied by the overlying seawater is almost completely removed from the pore water at depth of about 10 cm below the sediment surface. The nutrients such as ammonium and phosphate are produced through this process and subsequently accumulated in the pore water forming steep gradients near the sediment surface. Below the main sulfate redirection zone, a secondary peak of dissolved sulfate was often observed. Greal seasonal variation of the pore water nutrient profiles was observed, which was particularly clear in their maximum concentration as well as in their concentration gradient. The rate constants of sulfate reduction and nutrient regeneration, estimated by using a diagenetic model (Berner, 1980), differ by an order of magnitude between the summer and winter seasons. The difference in sediment temperature may account for most of the calculated variation. The C:N:P ratio, calculated from the pore water nutrient gradients also exhibits a slight seasonal difference. The organic matter being decomposed by sulfate reduction appears to be depleted in depleted in nitrogen, compared to the average marine organic matter.

• Journal of Life Science
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• v.13 no.4
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• pp.473-480
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• 2003

We analyzed the patterns of mineral ions and growth responses among symbiotic nitrogen fixing legumes by external nitrogen applications under salt gradients. Glycine max, Phaseolus angularis and Albizzia julibrissin showed remarkable growth inhibition above 40 mM NaCl treatments, but Cassia tora did not exhibit any visible injury symptom up to 100 mM NaCl treatments. As to ionic pattern, the $Na^+$ and $Cl^-$contents in leaves of G. max, P. angularis and A. julibrissin progressively increased with higher contents of external salinity. Compared to other plants, C. tora excluded $Na^+$more efficiently and maintained rather constant ionic contents in spite of high salt levels. With a few exception, these 4 legume plants exhibited better growth by the external nitrogen supply rather than the contribution of symbiotic nitrogen fixation only under saline condition.

• The Journal of the Convergence on Culture Technology
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• v.5 no.4
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• pp.373-378
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• 2019

In the marine area, the salt concentration in the soil increases, and the inland heavy metal pollution increases the damage of plants. In the inland industrial development area, researches on the genetic resources of plants together with the heavy metal accumulation of Co, Ni, Zn, and so on are required. Both of these problems have caused scientists to work hard to find plants that are likely to cause stress in plant roots. In this study, seeds of Arabis stelleri var. japonica collected near the shore were used for germination. The growth and development and tolerance of both Arabis and Arabidopsis seeds were investigated under laboratory culture conditions. As a result, Arabis showed resistance about 3 times in 250 mM nickle and cobalt, and more than 4 times in 1 mM zinc when compared to Arabidopsis. The tolerance of Arabis to Na salts increased by 20% or more at 50 mM concentration and Arabis was resistant to heavy metals and salt concentration. The accumulation of Na ions in the body was measured as a preparation for studying the intracellular mechanism. As a result, it showed a further decrease in resistance to ground water roots. It is considered that the activity of the exporting gene is important rather than the mechanism of accumulation.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.05a
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• pp.30-38
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• 1997

고속도로변에 설치된 retention pond는 drainage system의 일부분으로 우기에 빗물의 양을 조절하고 고속도로 노면에서 운반되어 retention pond에 유입된 오염된 입자를 침전, 제거시키기 위해 설치되었다. 빗물에 입자상태로 이동된 납, 아연, 카드뮴를 제거하기 위해 설치된 retention pond의 효과를 평가하기 위해 수리지질학적 연구 및 부유퇴적물의 물리화학적 특징을 규명하기 위한 연구가 수행되었다. 부유퇴적물과 비교하기 위해 심하게 오염된 roadside soil과 오염되지 않은 background soil에 대해서도 연구가 수행되었다. 부유퇴적물의 중금속함량은 background Sologne soil에 비해 원소에 따라 2-8배 높다. 그러나, roadside soil의 중금속함량은 부유퇴적물에 비해 7-26배 높다. Sequential extraction methods를 이용하여 분석한 결과 심하게 오염된 roadside soil에 존재하는 납, 아연, 카드뮴은 대부분 쉽게 용해될 수 있는 상태 (Fraction FII, FIII)로 존재하며 반면에 규산염광물과 수반되는 금속함량의 비율은 매우 낮다. 부유퇴적물에서는 규산염광물과 수반되는 금속함량이 전체 금속함량의 1/3까지 크게 증가한다. Roadside soil 과 부유퇴적물사이의 중금속함량 차이가 매우 큰 것은 중금속의 대부분이 retention pond에 이르기 전에 고속도로변과 배수로 일부에 축적되어 모두 상실하기 때문이다.

• Journal of Korean Medicine for Obesity Research
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• v.1 no.1
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• pp.13-20
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• 2001

Obesity is an excess of body fat frequently resulting from an imbalance between energy intake and expenditure, raises the risk of morbidity from chronic diseases such as hypertension, dyslipidemia, type 2 diabetes, coronary heart disease, stroke, fatty liver and osteoarthritis. Recently we experienced a 51 years old obese woman who was accompanied with hypertension, dyslipidemia and osteoarthritis. Through weight reduction program(very low calorie diet, Chegameuiintang, exercise) during 3 months, total weight loss was 17.0kg, her condition was improved.