• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.41-44
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• 2014

This study focused on the effect of the biomass blended ratio on air-staged pulverized coal furnace. The hybrid NOx reduction technology between fuel blending and air staging has been applied in an air-staged pulverized coal fired furnace. The results indicated that co-firing biomass with coal could reduce NOx emissions in an air-staged combustion. In addition, carbon burnout and flame temperature increased under the air-staged condition. A dominant synergistic effect on NOx reduction and carbon burnout was observed when biomass co-firing with coal was applied in air staged combustion.

• 한국연소학회:학술대회논문집
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• 2012.11a
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• pp.175-176
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• 2012

As a carbon neutral fuel, biomass can be converted into various types of high-valued products such as synthetic natural gas (SNG), Hydrogen, Fischer - Tropsch (FT) diesel. and valuable chemicals. In order to make above mentioned products, gasificaion process is essential as energy utilization platform of solid biomass. In this study, state of the art and prospect for biomass gasification technologies are presented.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2011.10a
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• pp.289-296
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• 2011

Recently, much of forest biomass has been obtained from the national forest management operation. Unfortunately, Korean Forest Services has a plan to use this forest biomass as energy fuels for wood pellets. Considering unhappy situation that about 80% of wood pulps has been imported, it is regarded as unwise decision. If forest biomass can be used to make pulps or other valuable woody products, we are able to double its economic value than the raw materials for wood pellets. In this study, we explored alternative raw materials for wood biomass used to make wood pellets. For this, fresh technology such as torrefaction was applied with the other lignocellulosic biomass.

• Ocean and Polar Research
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• v.41 no.1
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• pp.11-18
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• 2019

This acoustic experiment noted that fish species in Chilam-Gijang marine ranching area were more densely distributed in the pelagic zone during nighttime than daytime. In each season, the gill nets caught 15 different fish species and the estimated average target strengths were -44.0 dB and -44.4 dB for autumn and winter surveys, respectively. The estimated autumn fish biomass were 7.7 tons and 26.0 tons during daytime and nighttime, respectively. Winter biomass was 2.27 tons and 30.97 tons during daytime and nighttime, respectively. Different fish species form schools that exhibit different movements and behaviors, and thereby occupy varying water layers. These results explained the estimated fish biomass, and variation with seasons and time of the surveys around artificial reefs in Chilam Bay, Korea.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.48 no.2
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• pp.128-136
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• 2012

Hybrid surveys using hydroacoustic and fish sampling gears such as trammel net, trap were conducted to investigate total biomass, distribution and dominant fish species of the demersal fishes in the marine ranching area (MRA) of Jeju. Four surveys were carried out in June, August, October and November using 38kHz quantitative echo sounder. Catch data using trammel net and trap were used to calculate biomass and to examine dominant fish species. Fish schools were mainly detected in the waters of 20 meters below and around Chagwido waters. By the result of fishing experiments, fish species living in MRA of Jeju were about 40 species, dominant fish species of a detectable fish such as Family Sparidae and Family Monacanthidae etc. were identified 59.4~68.8% of total biomass. Based on the hydroacoustic data, fish length-weight function and target strength information, mean density of the demersal fish estimated were as follows; 0.88g/$m^2$ on June, 1.12g/$m^2$ on August, 1.35g/$m^2$ on October and 1.18g/$m^2$ on November. An estimated average biomass in MRA of Jeju was founded 20.5 tons in 2007, 20.6 tons in 2008, 23.0 tons in 2009, 25.9 tons in 2010. The results showed that biomass of MRA is getting increased slowly. Therefore the hybrid survey method using hydroacoustic and fish sampling gears is assured an effective biomass survey in the waters of mixed species.

• Ocean and Polar Research
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• v.26 no.2
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• pp.113-120
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• 2004

The abundance, biomass and distribution of phytoplankton, bacterioplankton and heterotrophic protists in the Bering Sea were investigated from July to August 1999. Chlorophyll a concentrations in the surface waters ranged from 0.16 to $3.79{\mu}g\;l^{-1}$ Nano-phytoplankton were found to constitute from 63 to 98% of the total phytoplankton biomass, and were clearly the dominant primary producers. The biomass of bacterioplankton in the surface layers varied from 1.46 to $20.2{\mu}g\;C\;l^{-1}$ and accounted for 30% of the total phytoplankton biomass. The biomass of bacterioplankton integrated over a depth of 0 to 100m averaged 65.4% of the total phytoplankton biomass. The surface biomass of heterotrophic protists ranged from 1.2 to $27.4{\mu}g\;C\;l^{-1}$, and was within the same order of magnitude as that of bacterioplankton. Of the total biomass of heterotrophic protists in the upper 100m of the water column, 65% was attributed to protists in the nano-size class. The results of this study suggest that bacteria and nano-protists are important components of the planktonic community in the Bering Sea during the summer season. The abundance of bacterioplankton and planktonic protists decreased from the western to northeastern and eastern regions of the Bering Sea. The abundance of these organisms also decreased with depth. The available evidence suggests that variation in the abundance and distribution of these organisms may be affected by water currents and vertical temperature variation in the Bering Sea.

• Korean Chemical Engineering Research
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• v.44 no.2
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• pp.107-113
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• 2006

Not only Cr(VI) is very toxic, but also it is a major pollutant in soil and groundwater. Thus Cr(VI)-containing wastewater must be treated before being discharged into the environments. Recently, biosorption technology using abundant biomass has been considered as an innovative one for removing Cr(VI) from aqueous solution. In this review article, current research and future works on Cr(VI) biosorption were widely described. Particularly, the removal mechanism of Cr(VI) by biomass was described in detail, which has been misunderstood by many researchers until now.

• Microbiology and Biotechnology Letters
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• v.45 no.1
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• pp.51-56
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• 2017

Cellulosic biomass is a renewable source for biofuel production from non-edible biomass. An optimized pretreatment process is required for the efficient utilization of cellulosic biomass. Among various pretreatment processes, the use of ionic liquids has been reported recently. However, the residual ionic liquid after pretreatment acts as an inhibitor of microbial fermentation. Recently, we isolated mutant Saccharomyces cerevisiae strains resistant to the ionic liquid 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) by using a directed evolutionary approach. When 3% [EMIM][Ac] was added to a medium containing 80 g/l of glucose, mutants D452-B2 and D452-S3 produced 35.6 g/l and 36.3 g/l of ethanol, respectively, for 18 h while the parental strain (S. cerevisiae D452-2) produced 1.3 g/l of ethanol. Thus, these mutant S. cerevisiae strains might prove advantageous when ionic liquids are used for biofuel production from cellulosic biomass.

• Journal of the Korean Wood Science and Technology
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• v.25 no.4
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• pp.45-50
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• 1997

This research was studied for dissolving pulp preparation as the raw material of viscose rayon from woody biomass by solvolysis pretreatment. In the change of pulp characteristic after solvolysis pretreatment, the following results were obtained. In the case of solvolysis pretreatment, we have obtained pulp that high purity cellulose, and degree of polymerization was inclined to decrease less than 440 on the phosphoric acid as catalyst. Comparing phosphoric acid and formic acid as catalyst in the solvolysis pretreatment, using on formic acid catalyst is superior to phosphoric acid catalyst for making dissolving pulp.

• Ocean and Polar Research
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• v.22 no.1
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• pp.37-43
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• 2000

Epiphytic communities on marine plants of Seychelles (Indian Ocean Island group associated with East Africa) were investigated in January - March of 1989 during the $15^{th}$ biological voyage of the research vessel cademic Alexander Nesmeyanov. A seagrass species, Thalassodendron ciliatum, and macroalgae (Sargassum spp. and Halimeda spp.) were tested for host substrates and biomass of their dominant epiphytes were assessed. Also, in order to understand the effect of shading and nutrient filtering by epiphytes, two series of photosynthetic rates were compared for Th. ciliatum host leaves having 10% and no epiphytes. Total of 84 species of algae and main taxons of benthic animals were identified from three different host plants. An average biomass of the epiphytes on Th. cihiatum was $184.6g\;kg^{-1}$ and dominant species were green alga Halimeda opuntia, red algae Dictyurus occidentalis and Gelidiella myrioclada. These dominant species and their biomass were remarkably varied with depth increment. On Sargassum spp., an average biomass of the epiphytes was $0.18g\;kg^{-1}$ and the maximum biomass was never exceeded $0.16g\;kg^{-1}$. In the case of Halimeda spp. an average biomass of the epiphytes was $8.0g\;kg^{-1}$, and dominant species were Peyssonnelia dubyi, sponges and decapods. Photosynthetic rates of Th. ciliatum were significantly reduced in the leaves having 10% epiphytes (1.72 times lower, t=6.718, p<0.001).