• KEPCO Journal on Electric Power and Energy
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• v.2 no.2
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• pp.143-165
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• 2016

The amount of greenhouse gas emission reduction based on INDCs (Intended Nationally Determined Contributions) submitted to UN by each party is not sufficient to achieve the Paris Agreement's aim to "hold the increase in the global average temperature to well below $2^{\circ}C$ above pre-industrial levels and to pursue efforts to limit the temperature increase to $1.5^{\circ}C$" which was determined in the $21^{st}$ Conference of the Parties to the UNFCCC (COP 21). Accordingly, the emission reduction target of each party will be revised for the $2^{\circ}C$ goal. Among the several options to reduce the carbon emission, CCS (Carbon Capture and Storage) is a key option to curb $CO_2$ emissions from large emission sources such as fossil-based power plants, cement plants, and steel production plants. A large scale CCS demonstration projects utilizing $1^{st}$ generation $CO_2$ capture technologies are under way around the world. It is anticipated, however, that the deployment of those $1^{st}$ generation $CO_2$ capture technologies in great numbers without government support will be difficult due to the high capture cost and considerable increase of cost of electricity. To reduce the carbon capture cost, $2^{nd}$ and $3^{rd}$ generation technologies are under development in a pilot or a bench scale. In this paper, current status of large scale CCS demonstration projects and the $2^{nd}$ and $3^{rd}$ generation capture technologies are summarized. Novel capture technologies on wet scrubbing, dry sorbent, and oxygen combustion are explained in detail for all capture areas: post-combustion capture, pre-combustion capture, and new combustion technologies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.6
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• pp.731-737
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• 1992

The specific attributes of aroma quality of canned tuna meat were investigated before and during refrigerated storage. Fresh, cooked tuna, beefy and meaty flavor notes of canned tuna meat were changed to card-boardy(1 week storage), oxidized fat-like(2 weeks storage), fatty acid-like and heavy oxidized fat-like(3 weeks storage), and then moldy and painty(4 weeks storage) flavor notes during storage in refrigerator at $4^{\circ}C.$ More than 126 peaks of volatile compounds collected from canned tuna meat were separated on Carbowax 20M capillary column of gas chromatographic analysis. Of the peaks, 54 compounds were identified by mass spectral data, matching $I_E$ values, and sniffing the effluent of each peak from GC detector. The contents of many low molecular weight compounds eluted with early retention times were decreased, whereas some other new compounds eluted with longer retention time were formed during storage. The compounds increased up to 3 weeks of storage and then decreased at extended storage time(4 weeks) were 1-penten-3-ol, 3-penten-2-ol, heptanal, limonene, 1-pentanol, octanal, 1-hexanol, nonanal, 2-octanone, 2-nonanone, 1-heptanol, benzaldehytde and some methyl substituted benzenes. p-Thiocresol, 2-chlorophenol, and 2-heptylthiophene were formed after 4 weeks of storage, but not detected in fresh canned tuna. Therefore, these compounds could be used as indicators for the quality changes during refrigerated storage.

• Applied Biological Chemistry
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• v.42 no.1
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• pp.12-19
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• 1999

To improve biopolymer productivity and properties of Bacillus strains, protoplast fusion was performed between biopolymer producing Bacillus subtilis K-1 and lactose utilizing Bacillus coagulans. The results were as follows; Protoplasts mixed in fusion fluid containing 33% PEG 6000, 1% PVP and 10 mM $CaCl_2$ were reacted for 5 min at $37^{\circ}C$ and then centrifused protoplasts were directly overlaid on the selective media containing $100\;{\mu}g/ml$ antibiotics and incubated for 3 days. At this conditions, the frequency of protoplast fusion was generally in the range of $4.6{\times}10^{-5}\;to\;1.8{\times}10^{-7}$ in ratio. Segregation ratio was observed between 1 to 6% indicating genetic stability of all the fusants. Fusants growth were also observed on the media contained amino acid and antibiotics as required marked materials. DNA contents of the selected fusants were 1.6 to 2.7 times more than that of parent strains. With observation by TEM microscopy, spherical protoplasts were first released from the swollen parental cells and then contracted to fuse in the process of fusion. And fused cells were observed representative vesicle. Originally, the parental cells were observed as in the morphology of thick-walled and double membrane-surrounded rod shape with TEM microscopy.

• The Korean Journal of Physiology
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• v.17 no.1
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• pp.55-61
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• 1983

Effects of SITS (4-acetamido-4'-isothiocyano-2, 2'-disulfonic stilbene) on a $Na^+$ transport, tissue oxygen consumption and Na-K-ATPase activity were studied in isolated frog skin preparations. $Na^+$ transport was estimated by measuring the short-circuit current(SC) across the skin; oxygen consumption was measured in separated epidermis as well as in intact skin; and Na-K-ATPase was assayed in $24,000{\times}g$ fraction of epidermal homogenates. The SCC across the skin Was rapidly and substantially reduced in the presence of 10 mM SITS in the medium bathing the outside(mucosal) surface of the skin. When the drug was added to the inside(serosal) bathing medium, there was about 20 min delay for inhibition of SCC and the effect was less pronounced. The above effect of SITS was independent of the presence of $Cl^-$ in the bathing medium. The oxygen consumption of the skin tissue was not affected by SITS, but the Na-K-ATPase activity of a subcellular fraction of the skin was significantly inhibited. These results suggest that SITS retards $Na^+$ transport across the frog skin primarily by interfering $Na^+$ entry across the mucosal membrance of the epithelial cell, although an effect on $Na^+$ pump can not be ruled out completely.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.5
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• pp.581-585
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• 2005

Five lactic acid bacteria (LAB) including 2 Lactobacillus strains isolated from Kimchi were evaluated to determine the binding ability to Caco-2 cells and $AFB_1$. LAB were divided into three different groups ; viable, heat-treated, and acid-treated cells. In the radioactive-labeling assay for bound cell counting, viable Lactobacillus Plantarum KCTC 3099 showed the higher adhesion to Caco-2 cells with the binding capacity of $39.2\%$, which was $149\%$ higher than Lactobacillus rhamnosus GG as a positive control. Leuconostoc mesenteroids KCTC 3100 showed the similar binding ability to L. rhamnosus GG. After 1 hour incubation at $37^{\circ}C$ with $AFB_1$, viable L. Planterum KTCC 3099 removed the toxin by $49.8\%$, which was similar level to L. rhamnosus GG. Both heat- and acid-treated groups showed high binding effect but acid-treated group was more effective for both Caco-2 cell binding and $AFB_1$ removal than the other. These results indicate that components of bacterial cell wall might be involved in tile binding to intestinal cells and toxins.

• The Korean Journal of Ecology
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• v.22 no.1
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• pp.39-43
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• 1999

Serratia marcescens, an enterobacterium of gram-negative bacteria, is characterized by resistance of the admium. Cadmium sensitive PM strain did not grow in the medium at cadmium concentration of 50 ppm. PA strain was induced to accommodate to cadmium by cultivating the mother strain (PC strain) in the medium with 50 ppm cadmium. As compared with PC and PM strains, PA strain revealed the excellent growth in cadmium media and accumulated four to five times higher cadmium concentration in cell than other strains. PA strain accumulated 23% of cadmium in cells when cultured in medium treated with 100 ppm cadmium and this cadmium was more accumulated in cytosol fractions than membrane fractions. Analysis by TEM indicated that cadmium was concentrated as a form of granule in cytosol. In protein patterns of cell after the treatment of cadmium, two inducible proteins (28 KDa and 64 KDa) and one reducible protein (45 KDa) were detected by SDS-PAGE. By Atomic Absorption Spectrophotometer, the amounts of cadmium attached to inducible proteins of 28 KDa and 64 KDa were 318.28 ㎍ and 325.37 ㎍ per gram of protein, respectively. It is assumed that these inducible proteins play an important role in the mechanism of cadmium accumulation in cells. A plasmid of 23Kbp was found in S. marcescens. The ability of resistance to cadmium in plasmid was confirmed by curing experiments.

• Journal of the Korean Geosynthetics Society
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• v.6 no.1
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• pp.9-16
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• 2007

Geotextile is one of the most useful and effective polymer material in civil construction works and the main function of geotextile is separation, reinforcement, filtering and drainage. Recently, because of the shortage of natural rock, traditional forms of river and coastal structures have become very expensive to build and maintain. Therefore, the materials used in hydraulic and coastal structures are changing from the traditional rubble and concrete systems to the cheaper materials and systems. One of these alternatives employs geotextile tube technology in the construction of coastal and shore protection structures, such as embankment, see dyke, groins, jetties, detached breakwaters and so on. Geotextile tube technology has changed from being an alternative construction technique and, in fact, has advanced to become the most effective solution of choice. This paper presents case history of sea dyke filter construction using geotextile tube mattress and also, various issues related to the tube mattress design and construction technology.

• KSBB Journal
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• v.16 no.4
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• pp.403-408
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• 2001

Distillation condensate generated from downstream processing of microbial alcohol fermentation imposes a serious burden to biological wastewater treatment or anaerobic digestion due to its high contents of SS (suspended solids) and TN (total nitrogen), A pilot scale microfiltration of the stillage condensate with a stainless steel SCEPTER membrane of 0.1 ${\mu}$m pore size was carried out to remove SS which was mostly composed of microbial cell residue. A stable permeate flux was achieved when the decanter effluent containing 0.7% of SS was filtered under the conditions of X10 VCR (volume concentration ratio), 2.5 bar of TMP (transmembrane pressure), and 60$^{\circ}C$. When stillage condensate with 2.6% SS was treated directly with microfiltration, VCR below X3 was recommended for a long duration of filtration. The permeate and retentate obtained from microfiltration were recycled to make-up medium of fermentation. Adding permeate or retentate up to 30% of fermentation volume showed no distinguished undesirable influence during the course of alcohol fermentation. Although only slight improvements in the final amount of CO$_2$ evolution and alcohol content were observed, fermentation rate increased so that the required time to reach 450 L/ton of CO$_2$ evolution was shortened to 72% of that with normal media.

• Journal of the Korean Chemical Society
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• v.48 no.6
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• pp.590-598
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• 2004

The preconcentration and determination of trace Cu(II) and Pb(II) on calcium alginate beads in aqueous solution were studied. A calcium alginate beads were prepared by adding an alginic acid to sample solution contained Ca(II). Some following conditions were optimized: the pH of sample solution, amount of alginic acid, and stirring time for effective adsorption; the type and concentration of acid, and sonication time in an ultrasonic vibrator for the perfect de-sorption. A sample solution was prepared with Cu(II) and Pb(II) in DI water. And Ca(II) and ethanol was added into the sample solution. The pH of the final sample solution was controlled with buffer solution. The alginic acid were dispersed in the sample solution by a magnetic stirrer. This mixture was stored in room temperature for 30 min to form a calcium alginate. After the beads were filtered and washed on a membrane filter, the analytes were redissolved from the beads by an ultrasonic vibration of 10 minutes in 1.0M $HNO_3$ solution. The effect of diverse ions on the adsorption of analytes were studied. This procedure was applied for the analysis of two real samples. The recoveries in spiked samples were $90.4{\sim}104.3%$ for analytes.

• The Korean Journal of Zoology
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• v.31 no.3
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• pp.165-176
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• 1988

Stmcturai changes at the surfaces of oocytes of Pseudopotamilla occelata were examined by electron microscopy. The oocytes, which grow up to the flnai stage in the same coelomic fluid, once released from the ovary at 5 $\mu$ m stage, change in the structure of the vitelilne envelopes. Microvilli were found to change gready in structure, abundance and behaviour dudng oogenesis. Microvilli are short and bifurcated at the previtellogenic stages and grow in size, but the number increases only during previtellogenesis but decreases during vitellogenesis. Glycocaiyx structures begin to form at the tips of microvitli at the early previtellogenic stages and become more abundant as oocytes grow and remain at the final stage of oogenesis. The tips of microvilli are separated from the stems at the late vitellogenic stages to form vesicles simultaneously with retraction of the microvilli. Vitelline envelope consists of outer, intermediate and inner layers at the previtellogenic stages. However, the inner layer becomes thickened and differendated into two sublayers at 80 $\mu$m stage, - while the outer and intermediate layers remain constant in the thickness. These structural changes were presumably the results of functional differentiation of the vitelline envelope throughout oogenesis even in the same milleu.