• 한국물환경학회지
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• 제28권2호
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• pp.238-246
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• 2012

Organic matters budget in Lake Hoengseong were monthly investigated from April 2009 to November 2009. The intense rainfall occurred at between July and August and the hydrological factors were highly varied during the rainfall season. By the concentrated rainfall, the elevation, influx and efflux were sharply increased and the turbid water was also flowed into the middle water column in Lake. The inflow of turbid water increased the nutrient concentrations in water body and this appears to stimulate of phytoplankton regard as the primary productivity of influx of organic matter. Monthly average concentration of dissolved organic carbon (DOC) was generally higher than the particulate organic carbon (POC) concentration in Lake, but Temporal and spatial variation of POC concentration was higher than DOC and the maximum POC concentration was recorded in surface water in August, had the highest phytoplankton biomass. Organic carbon concentration in inflow site was rarely changed during the dry season, but the concentration was rapidly increased by the initial intense rainfall. In organic matters budget, the most of the organic matters was inflowed from the inflow site at rainfall season. Especially, the influx of allochthonous organic matters during the intense rainfall was 72.4% in the total influx organic matters.

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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• pp.237-240
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• 2000

회분식 발효를 실시하여 균주의 최적 발효조건을 구하여 세포 재순환식 연속 발효 공정에 적용한 결과, CSL의 최적 함량은 2.5%로 나타났으며, 수율과 생산성은 각각 0.80g total acid/g glucose, 0.26g total acid/L/h이였다. 연속 발효 결과, 최대 생산물 생산성은 희석률 0.2/h에서 3.32g organic acid/L/h을 얻었다. 최적 추출시스템은 30%w/w TOA/MIBK로 나타났으며, Membrane Contactor을 이용한 추출에서는 수용액상의 200ml/min, 추출상은 100ml/min의 유량을 갖는 Counter-current가 최적 조건임을 확인했고, 또한 수용액상과 추출상의 접촉 부피비는 2:1이 여러 가지 요인을 고려했을 때 최적 조건임을 확인했다. 실제 발효를 통해 생성된 유기산의 추출은 1:1의 부피비로 counter-current로 접촉시켰을 때 Acetic acid 가 56% Propionic acid가 72.41%의 추출력을 얻을 수 있었다.

• Biotechnology and Bioprocess Engineering:BBE
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• 제6권5호
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• pp.341-346
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• 2001

For the purpose of mass producing Monascus red pigments optimum medium composition and environmental conditions were investigated in submerged flask cultures. The optimum carbon and nitrogen sources were determined to be 30g/L of glucose and 1.5 g/L of monosodium glutamate (MSG). Of the three metals examined, Fe$\^$2+/ showed the strongest stimulatory effect on pigment production and some stimulatory effect was also found in Mn$\^$2+/. Optimum pH and agitation speed were determined to be 6.5 and 700 rpm, respectively. Under the optimum culture conditions batch fermentation showed that the maximum biomass yield and specific productivity of red pigments were 0.20 g DCW/g glucose and, 32.5 OD$\sub$500/g DCW$\^$-1/h$\^$-1/, respectively.

• KSBB Journal
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• 제28권5호
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• pp.315-318
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• 2013

Ethanol fermentations were performed using separate hydrolysis and fermentation (SHF) processes with monosaccharides from pretreated seaweed, Eucheuma spinosum as the biomass. The pretreatment was carried out with 11% (w/v) seaweed slurry and 150 mM $H_2SO_4$ at $121^{\circ}C$ for 40 min. Enzyme hydrolysis after $H_2SO_4$ pretreatment was performed with Celluclast 1.5 L at $45^{\circ}C$ for 24 h. Five % active charcoal were added to hydrolysate to removed 5-hydroxy methylfurfural. Ethanol fermentation with 11% (w/v) seaweed hydrolysate was performed for 72~96 h using Kluyvermyces marxianus, Pichia stipits, Saccharomyces cervisiae and Candida tropicalis. Ethanol concentration was reached to 18 g/L by K. marxianus, 16 g/L by P. stipitis, 15 g/L by S. cerevisiae and 10 g/L by C. tropicalis, respectively. The ethanol yield from total monosugar was obtained 0.50 and ethanol productivity was obtained 0.38 g/L/h by K. marxianus.

• ALGAE
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• 제30권1호
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• pp.67-79
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• 2015

Planktivorous fish which limit zooplankton grazing have been predicted to increase algal biodiesel production in wastewater fed open reactors. In addition, tanks with higher algal diversity have been predicted to be more stable, more productive, and to more fully remove nutrients from wastewater. To test these predictions, we conducted a 14-week experiment in Houston, TX using twelve 2,270-L open tanks continuously supplied with wastewater. Tanks received algal composition (monocultures or diverse assemblage) and trophic (fish or no fish) treatments in a full-factorial design. Monocultures produced more algal and fatty acid methyl ester (FAME) mass than diverse tanks. More than 80% of lipids were converted to FAME indicating potentially high production for conversion to biodiesel (up to $0.9T\;ha^{-1}y^{-1}$). Prolific algal growth lowered temperature and levels of total dissolved solids in the tanks and increased pH and dissolved oxygen compared to supply water. Algae in the tanks removed 91% of nitrate-N and 53% of phosphorus from wastewater. Monocultures were not invaded by other algal species. Fish did not affect any variables. Our results indicated that algae can be grown in open tank bioreactors using wastewater as a nutrient source. The stable productivity of monocultures suggests that this may be a viable production method to procure algal biomass for biodiesel production.

• 신재생에너지
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• 제9권2호
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• pp.5-14
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• 2013

The efficiency of microwave-assisted acid hydrolysis of seaweeds for the production of ethanol was investigated and its effect on hydrolysis into reducing sugar and fermentation into ethanol evaluated as compared with those by conventional heating. A brown seaweed, Laminaria japonica (10-100g/L) was hydrolysed under dilute acidic condition (0.5N $H_2SO_4$, $100^{\circ}C$) with two sorts of heating: microwave irradiation for ${\leq}10min$ and conventional heating for 10-60min. Microwave-assisted hydrolysis was shown to be more efficient. A similar range of reducing sugar and ethanol yields as with the conventional autoclave heating procedure(${\geq}30min$) was observed, but it was obvious that production of ethanol from microwave-assisted hydrolysis had a 3 times faster reaction rate leading to very short production times, lower energy consumption/loss than from the conventional heating mode, and higher biomass loading without significant reducing ethanol yield, thus microwave-assisted acid hydrolysis is a potential alternative method for more effective hydrolysis of Laminaria japonica.

• 농촌지도와개발
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• 제23권4호
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• pp.471-481
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• 2016

이 연구의 목적은 미래 산림분야의 유망한 장기 일자리를 분석하고, 산림분야 일자리 수요-공급에 따른 유망한 일자리를 제안하는 데 있다. 연구방법으로는 산림분야 일반/전문직업을 도출하기 위해 전문가 델파이 연구 결과와 관련연구 결과를 비교, 분석 하였다. 연구결과 선정된 일자리는 최근 관심이 높아지고 있는 의료 및 복지와 관련된 직업, 산림 자체를 유지 관리 보호하는 직업, 기후변화에 따른 새로운 자원으로써 산림에서 구할 수 있는 유기물을 활용한 자원개발과 관련된 직업 등이었다.

• 한국수산과학회지
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• 제9권4호
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• pp.245-249
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• 1976

1. $1967\~1973$년까지 7개년간 한국 남해에서 국립수산진홍원이 조사한 동물성 플랑크론 존량 자료에서 동 해역의 동물성 플랑크론 년간 총 생산량을 추정하였다. 2. 남해역 $59,800\;km^2$ 1년동안에 생산되는 동물성 플랑크톤 총량은 약 $5.14\times10^6\~10.27\times10^6ton$으로 추정되며, 면적당 평균 생산력은 $86\~172ton/km^2/year$이다. 3. 동 해역에서의 영양단계간 에너지 전환효율 $15\%$, 동물플랑크톤 부터 유용어족까지의 먹이 전환단계를 2로 볼 때, 남해역의 유용어족 잠재 생산력은 $1.9\~3.9\;ton/km^2/year$로 추정된 다.

• Mycobiology
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• 제34권3호
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• pp.138-142
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• 2006

Soil cyanobacteria isolated from the rice paddy fields of 10 different locations across Korea were evaluated by agar plate diffusion test for antifungal activity. Aqueous, petroleum ether, and methanol extracts from one hundred and forty two cyanobacterial strains belonging to the 14 genera were examined for antifungal properties against seven phytopathogenic fungi causing diseases in hot pepper (Capsicum annuum L). Of total cyanobacteria, nine cyanobacteria (6.34%) exhibited antifungal effects. The nine cyanobacteria selected with positive antifungal activities were two species of Oscillatoria, two of Anabaena, three of Nostoc, one of Nodularia, and one of Calothrix. Alternaria alternata and Botrytis cinerea were inhibited by nine and eight species of cyanobacteria, respectively. Rhizopus stolonifer was suppressed by only methanol extract of Nostoc commune FK-103. In particular, Nostoc commune FK-103 and Oscillatoria tenuis FK-109 showed strong antifungal activities against Phytophthora capsici. Their antifungal activity at the late exponential growth phase is related to the growth temperature and not associated with the growth parameters such as cell biomass and $chlorophyll-{\alpha}$ concentration. The high inhibition levels of antibiotics were 22.5 and 31.8 mm for N. commune FK-103 and O. tenuis FK-109, respectively. The optimal temperature for antibiotic productivity was $35^{\circ}C$.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2005년도 국제학술회의
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• pp.22-46
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• 2005

Spatial and timely information on crop and filed conditions is one of the most important basics for rational and efficient planning and management in agriculture. Remote sensing, GIS, and modeling are powerful tools for such applications. This paper presents an overview of the state of the art in remote sensing of crop and field conditions with some case studies. It is also shown that a synergistic linkage between process-based models and remote sensing signatures enables us to estimate the multiple crop/ecosystem variables at a dynamic mode. Remotely sensed information can greatly reduce the uncertainty of simulation models by compensating for insufficient availability of data or parameters. This synergistic approach allows the effective use of infrequent and multi-source remote sensing data for estimating important ecosystem variables such as biomass growth and ecosystem $CO_2$ flux. This paper also shows a geo-spatial information system that enables us to integrate, search, extract, process, transform, and calculate any part of the data based on ID#, attributes, and/or by river-basin boundary, administrative boundary, or boundaries of arbitrary shape/size all over Japan. A case study using the system demonstrates that the nitrogen load from fertilizer was closely related to nitrate concentration of groundwater. The combined use of remote sensing, GIS and modeling would have great potential for various agro-ecosystem applications.