• Journal of Microbiology and Biotechnology
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• v.14 no.5
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• pp.932-937
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• 2004

In situ extraction by organic solvent was studied in order to improve the recovery yield of hydrocarbon from the culture of Botryococcus braunii, a green colonial microalga. When the solvent mixture of octanol as an extractive solvent and n-octane as a biocompatible solvent was added to a two-phase column, the algal growth was seriously inhibited, even at a low concentration of polar octanol. Therefore, a two-stage cell-recycle extraction process was proposed to improve the contact area between the organic phase and the aqueous phase. The hydrocarbon recovery with in situ cell-recycle extraction showed a three-fold increase (57% of cell) in yield over that with two-phase extraction. In addition, over 60% of the hydrocarbon could be recovered without serious cell damage by downstream separation when this process was applied to the culture broth after batch fermentation.

• Journal of the Korean Society of Tobacco Science
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• v.14 no.1
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• pp.79-86
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• 1992

Free and glycosidically bound volatiles from three green tobacco leaves(NC 82, KF 109 and Br-21) were separated by nonionic resin Amberlite XAD-2 adsorption column chromatography and election by selective solvents. Aglycones from the glycosidically bound fractions were released by enzymatic hydrolysis with almond B-glucosidase. A total of 20 components identified from free and glycosidically bound fractions, the major components were benzaldehyde, benzyl alcohol, 2-phenylethyl alcohol, 3-oxo- -ionol, 3-hydroxy-B-ionone, 3-oxo-7, 8-dihydro-n-ionol and scopoletin. Six Cl.B norisoprenoids identified in this study, which have been described to possess a characteristic tobacco aroma-enhancing effect, were not presented in free forms but rather bound glycosidic forms.

• Journal of Korean Institute of Industrial Engineers
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• v.26 no.2
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• pp.146-154
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• 2000

This study showed a way to develop web site of shopping mall through systematic identification of the interface elements affecting user's performance and subjective sensibility for Internet shopping mall. To quantify the effects of factors, simulators were designed and used in experiments. It was shown that location of 'Table of Contents'(left > right = up = down) and 'Menu' type(non_Drop down and page Movement = Drop down and page Movement > Drop down and non_age Movement) were the significant factors. However, whether 'Frame' was used or not, there was no significant difference. Also, in the evaluation of subjective sensibility, 'Background color' was a significant factor. And for 'Header & Scanning Column color', yellow color had a tendency to enhance satisfaction for 'simplicity', while green or blue color strengthened 'balance' feeling. But 'text style' was not significant.

• Journal of the Korean Society of Food Science and Nutrition
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• v.4 no.1
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• pp.49-53
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• 1975

The effect of natural condiments on peptic hydrolysis of casein in vitro has been studied, peptic activity was determined by the colorimetric method using folin reagent. The obstructive compounds on colorimetry from hydrolyzates of casein were separated by gel filteration method using sephadex G-10 column and 0.05M NaCl. Zinger and red pepper $(0.1{\sim}1.0%)$ were found to have slightly supressing effect for protein digestive action of pepsin. But garlic, green onion and onion acted as synergist for protein digertive action of pepsin.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.96-97
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• 2014

Green Frame is a column-beam structure built by steel frame joints embedded in the columns and beams. Here, the steel frame embedded in the columns and beams is not a standardized product, instead it needs to be order-produced. The quantity for each steel frame size should be calculated to estimate the quantity of steel frames to be manufactured. However, it is highly time-consuming and requires a lot of effort in calculating the quantity of steel frames, for there are a wide range of steel frame types that are embedded in the columns and beams. To solve this problem, the study proposes an algorithm for calculation of the amount of steel frames with ease and promptness. When a program is developed using the algorithm proposed in the study in connection to the information on precast concrete members prepared in the design phase, it is anticipated that the manpower required as well as the manufacturing time will be decreased.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.05a
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• pp.185-191
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• 2003

A numerical study on the hydrodynamic properties of a floating flexible breakwater consisting of triple vertical porous membrane structures attached to a floating rigid pontoon restrained by moorings is carried out in the context of two-dimensional linear wave-flexible body interaction theory. The tensions in the triple membranes are achieved by hanging a clump weight from its lower ends. The clump weight is also restrained properly by moorings. The dynamic behavior of the breakwater was described through an appropriate Green function, and the fluid multi-domains are incorporated into the boundary integral equation. Numerical results are presented which illustrate the effects of the various wave and structural parameters on the efficiency of the breakwater as a barrier to wave action. It is found that the wave reflection and transmission properties of the structures depends strongly on the membrane length taking major fraction of water column, the magnitude of tensions on membrane achieving by the clump weight, proper mooring types and stiffness, the permeability on the membrane dissipating wave energy.

• Journal of Life Science
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• v.28 no.12
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• pp.1416-1423
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• 2018

With strong biotin binding affinity ($K_D=10^{-14}M$), the tetrameric feature of streptavidin could be used to increase the antigen binding activity of a camel heavy chain (VHH) antibody through their fusion, here stained with biotinylated horseradish peroxidase and subsequent immunoassays ELISA and Western blot analysis. For this application, we cloned the streptavidin gene amplified from the Streptomyces avidinii chromosome by PCR, and this was fused to the gene of the 8B9 VHH antibody which is specific to green fluorescent protein (GFP) antigens. To express a soluble fusion protein in Escherichia coli, we used the pUC119 plasmid-based expression system which uses the lacZ promoter for induction by IPTG, the pelB leader sequence at the N-terminus for secretion into the periplasmic space, and six polyhistidine tags at the C-terminus for purification of the expressed proteins using an $Ni^+$-NTA-agarose column. Although streptavidin is toxic to E. coli because of its strong biotin binding property, this soluble fusion protein was expressed successfully. In SDS-PAGE, the size of the purified fusion protein was 122.4 kDa in its native condition and 30.6 kDa once denatured by boiling, suggesting the tetramerization of the monomeric subunit by non-covalent association through the streptavidin moiety fusing to the 8B9 VHH antibody. In addition, this fusion protein showed biotin binding activity similar to streptavidin as well as GFP antigen binding activity through both ELISA and Western blot analysis. In conclusion, the protein resulting from the fusion of an 8B9 VHH antibody with streptavidin was successfully expressed and purified as a soluble tetramer in E. coli; it showed both biotin and GFP antigen binding activity suggesting the possible production of a tetrameric and bifunctional VHH antibody.

• Journal of Korea Soil Environment Society
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• v.4 no.2
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• pp.127-136
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• 1999

In the past several years phytoremediation, defined as the use of plants for removing contaminants from media such as soils or water, has attracted a great deal of interest as a potentially useful remediation technology We attempted to assess the effectiveness of phytoremediation of diesel-contaminated soils in a green house. Screening test for selecting an appropriate plant was performed by observing the harmful effects of diesel dosage on the growth of 4 plants. Alfalfa was selected as a potentially useful plant among corn and barnyard grasses due to its high tolerance to the toxicity of diesel in growth. Bioremediation of the artificial diesel-contaminated soil packed in the PVC columns(0.3m in diameter $\times$ 1m in length) with air supplied, alfalfa planted, and alfalfa and air supplied was investigated for 100 days. The results of the column test showed plant effects on enhancing the biodegradation of diesel in the contaminated soils compared to the control column which had no plant. Injecting air to the columns during phytoremediation also showed additional effects on the removal rate of diesel. Comparison of microbial activity in each test column showed a beneficial effect of plants in the soil remediation processes. This results can be explained microbial activity in rhizosphere is a crucial factor for removing diesel.

• Journal of Energy Engineering
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• v.20 no.1
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• pp.13-20
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• 2011

The high fuel flexibility of Micro Gas Turbine(MGT) has boosted their use in a wide variety of applications. Recently, the demand for biogas generated from the digestion of organic wastes and landfill as a fuel for gas turbines has increased. We researched the influence of firing landfill gas(LFG) on the performance and operating characteristics of a micro gas turbine combined heat and power system. $CH_4$ and $CO_2$ simultaneous recovery process has been developed for field plant scale to provide an isothermal, low operating cost method for carrying out the contaminants removal in Land Fill Gas(LFG) by liquid phase catalyst for introduce into the green house for the purpose of $CO_2$ rich cultivation of the plants. Methane purification and carbon dioxide stripping by muti panel autocirculation bubble lift column reactor utilizing Fe-EDTA was conducted for evaluate optimum conditions for land fill gas. Based on inflow rate of LFG as 0.207 $m^3$/min, 5.5 kg/$cm^2$, we designed reactor system for 70% $CH_4$ and 27% $CO_2$ gas introduce into MGT system with $H_2S$ 99% removal efficiency. A green house designed for four different carbon dioxide concentration from ambient air to 1500 ppm by utilizing the exhaust gas and hot water from MGT system.

• Analytical Science and Technology
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• v.25 no.6
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• pp.460-466
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• 2012

An environmentally friendly, so-called green, high performance liquid chromatography method was developed and validated for the determination of trans, trans-muconic acid (t,t-MA) in human urine as a biomarker of benzene exposure. After urinary t,t-MA was extracted and enriched using solid-phase extraction, a MF-Ph1 SG80 ($150mm{\times}2.0mm$ I.D., 5 ${\mu}m$) column with a mobile phase of 10 mM $KH_2PO_4$ containing 0.1% $H_3PO_4$ was used for isocratic separation of t,t-MA with UV detection at 259 nm. The calibration curve was constructed in the range of 0.1-5.0 mg/L with good linearity ($r^2$=0.9992). The intra-day and inter-day precision (as RSD) were 0.9-8.5% and 3.1-4.5%, respectively. The average recovery ranged from 97.5% to 101.7%. The green sample preparation and separation with no organic solvents were successfully achieved. The validated method would be suitable for the routine biological monitoring of benzene exposure in the occupational settings.