• KSBB Journal
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• v.23 no.4
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• pp.297-302
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• 2008

In this work, the amounts of Flavone C-glycosides homoorientin, orientin extracted from Black bamboo by various ultrasonic waves frequency (35, 72, 170 KHz, 300 Watt $\pm$1) time (15, 30, 60 min) and temperature ($25^{\circ}C$) were compared using 50% aqueous ethanol solution. And describesanalysis of the antioxidant potential of Black bamboo using an high-performance liquid chromatography (HPLC) on-line $ABTS^+$antioxidant screening method. In conjunction with the analysis of their 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid ($ABTS^+$) radical scavenging ability. The optimum operating conditions were experimentally determined to analyze the Flavone C-glycosides homoorientin, orientin in the pretreatment ultrasonic extracts. From the results, the effect on extraction yield of variations in frequency, solvent composition and extraction time was investigated. The highest yield of Black bamboo was obtained by ultrasonic waves with a frequency of 72 KHz and an extraction time of 60 min, The extraction frequency 35 KHz ($25^{\circ}C$), time 30 min was selected as an optimal antioxidant activity condition.

• Journal of Ginseng Research
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• v.38 no.2
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• pp.136-145
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• 2014

Background: This study aimed to develop a biocontrol system for ginseng root rot caused by Fusarium cf. incarnatum. Methods: In total, 392 bacteria isolated from ginseng roots and various soils were screened for their antifungal activity against the fungal pathogen, and a bacterial isolate (B2-5) was selected as a promising candidate for the biocontrol because of the strong antagonistic activity of the bacterial cell suspension and culture filtrate against pathogen. Results: The bacterial isolate B2-5 displayed an enhanced inhibitory activity against the pathogen mycelial growth with a temperature increase to $25^{\circ}C$, produced no pectinase (related to root rotting) an no critical rot symptoms at low [$10^6$ colony-forming units (CFU)/mL] and high ($10^8CFU/mL$) inoculum concentrations. In pot experiments, pretreatment with the bacterial isolate in the presumed optimal time for disease control reduced disease severity significantly with a higher control efficacy at an inoculum concentration of $10^6CFU/mL$ than at $10^8CFU/mL$. The establishment and colonization ability of the bacterial isolates on the ginseng rhizosphere appeared to be higher when both the bacterial isolate and the pathogen were coinoculated than when the bacterial isolate was inoculated alone, suggesting its target-oriented biocontrol activity against the pathogen. Scanning electron microscopy showed that the pathogen hyphae were twisted and shriveled by the bacterial treatment, which may be a symptom of direct damage by antifungal substances. Conclusion: All of these results suggest that the bacterial isolate has good potential as a microbial agent for the biocontrol of the ginseng root rot caused by F. cf. incarnatum.

• Journal of the Institute of Electronics Engineers of Korea TE
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• v.39 no.1
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• pp.22-30
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• 2002

The nucleation of copper(Cu) with (hfac)iu(VTMS) oganometallic precursor is investigated for Si, $Sio_2$, TiN, $W_2N$ substrates. As the deposition temperature is increased, the dominant growth mechanism is observed to change from the nucleation of Cu particles to the clustering of Cu nuclei around $180^{\ciec}C$, independent of the employed substrates. It is also observed that the cleaning of substrate surfaces with the diluted HF solution improves the selectivity of Cu nucleation between TiN and $Sio_2$ substrates. Dimethyldichlorosilane treatment is found to passivate the surface of TiN substrate, contrary to the generally accepted belief, when the TiN substrate is cleaned by $H_2O_2$ solution before the treatment.

• The KSFM Journal of Fluid Machinery
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• v.16 no.1
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• pp.56-60
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• 2013

Non-conventional oil resources such as shale gas are becoming increasingly important and have drawn the attention of several major oil companies all over the world. Nevertheless, the market-changing growth of shale gas production in recent years has resulted in the emergence of environmental and water management challenges. This is because the water used in the hydraulic fracturing process contains large amount of pollutants including ions, organics, and particles. Accordingly, the treatment of this flowback water from shale gas plant is regarded as one of the key technologies. In this study, we examined the feasibility of membrane distillation as a treatment technology for the water from shale gas plants. Direct contact membrane distillation (DCMD) is a thermally-driven process based on a vaper pressure gradient across a hydrophobic membrane, allowing the treatment of feed waters containing high concentration of ions. Experiments were carried out put in the lab-scale under various conditions such as membrane types, temperature difference, flow rate and so on. Synthetic feed water was prepared and used based on the data from literature. The results indicated that DCMD is suitable for treating not only low-range flowback water but also high-range flowback water. Based on the theoretical calculation, DCMD could have over 80% of recovery. Nevertheless, organic pollutants such as oil and surfactant were identified as serious barriers for the application of MD. Further works will be required to develop the optimum pretreatment for this MD process.

• KSBB Journal
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• v.23 no.3
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• pp.276-280
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• 2008

In this study, the productivity of bioethanol obtained from various domestic raw materials (barley, brown rice, corn and sweet potato) by simultaneous saccharification and fermentation (SSF) process was estimated. Also, optimal conditions of temperature, time and enzyme concentration in gelatinization and liquefaction process were investigated. As a result, corn showed high ethanol yield of 90.45% and sweet potato had a rapid fermentation time. Productivity of bioethanol increases in accordance with the starch value of raw materials except brown rice. Therefore, it is very important to understand the structure of starch. Further studieson the characteristics of raw materials are necessary to enhance the productivity of bioethanol.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.30 no.4
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• pp.18-27
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• 1998

Biopulping is defined as the treatment of wood chips with lignin-degrading fungi prior to pulping. Fungal pretreatment prior to mechanical pulping reduces electrical energy requirements during refining or increases mill throughput, improves paper strength, reduces the pitch content, and reduces the environmental impact of pulping. Our recent work involved scaling up the biopulping process towards the industrial level, investigating both the engineering and economic feasibility. We envision the process to be done in either a chip-pile or silo-based system for which several factors need to be considered: the degree of decontamination, a hospitable environment for the fungus, and the overall process economics. Currently, treatment of the chips with low-pressure steam is sufficient for decontamination and a simple, forced ventilation system maintains the proper temperature, humidity, and moisture conditions, thus promoting uniform growth of the fungus. The pilot-scale trial resulted in the successful treatment of 4 tons of wood chips (dry weight basis) with results comparable to those on a laboratory. Larger, 40-ton trials were also successful, with energy savings and paper properties comparable with the laboratory scale. The overall economics of the process also look very favorable and can result in significant annual savings to the mill. Although the current research has focused on biopulping for mechanical pulping, it is also beneficial for sulfite chemical pulping and some applications to recycled fiber have been investigated.

• Korean Journal of Environmental Agriculture
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• v.18 no.1
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• pp.48-53
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• 1999

In this study, various batch tests were performed to examine the utilization of waste oyster shells for removal of $PO_4^{3-}-P$ in livestock wastewater, because waste oyster shells have been known to be very porous and to have alkaline minerals such as calcium and mangnesium. $PO_4^{3-}-P$ removal rate were increased by waste oyster shells, as specific surface area and contact efficiency per unit area of their were increased. Generally, it could be showed that $PO_4^{3-}-P$ removal rate were very influenced by particle size, dosage and temperature. At low pH of initial reactions, it would be showed that $PO_4^{3-}-P$ removals were directly influenced by adsorption but crystallization process were dominated with passed time and pH increasing. The SEM observed that the variations were hardly seen, but particle sizes of waste oyster shell were relatively big after reactions and showed forms of smaller plate than before reactions.

• The Korean Journal of Mycology
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• v.15 no.1
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• pp.23-28
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• 1987

Physicochemical factors influencing the $11{\alpha}$, hydroxylation of progesterone by Rhizopus nigricans Ehrenberg were studied. The higher is the concentration of progesterone. the shorter time is need to attain maximum yield in the $11{\alpha}-hydroxyprogesterone$. High concentration in progesterone was supposed to inhibit the hydroxylation reaction of the $11{\alpha}-hydroxyprogesterone$. The range of optimum pH and temperature appeared to be rather broad and these conditions were similar to those of optimum growth of the mycelia. Agitation at a higher speed than a certain limit, and the presence of sugars accelerated the $11{\alpha}-hydroxyprogesterone$ reaction. Glucose was found to be more effective for the reaction using spores rather than mycelia as enzyme sources. Organic solvents were proved to supress the enzyme activity, which decreased with increase in the concentration of the organic solvents and in the time for pretreatment with the solvents.

• The Korean Journal of Physiology
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• v.29 no.2
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• pp.301-307
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• 1995

To explore electrophysiological properties of the ${\delta}-Opioid$ receptors artificially expressed in the mammalian cell, effect of an opioid agonist DPDPE $(1\;{\mu}M)$ on the voltage-sensitive outward currents was examined in the HEK293 (human embryonic kidney) cells transfected with ${\delta}-Opioid$ receptor cDNA cloned from NG-108-15 $(neuroblastoma\;{\times}\;glioma\;hybrid)$ cDNA library. Also studied were effects of 8-bromo-cyclic AMP and naloxone on DPDPE-induced changes in the voltage sensitive outward current. The voltage sensitive outward currents were recorded using perforated patch technique at room temperature. In the non-transformed HEK293 cells, DPDPE did not alter voltage sensitive outward current, indicating that no native ${\delta}-Opioid$ receptor had been developed. However, $(1\;{\mu}M)$ DPDPE remarkably increased the voltage sensitive outward current in the transformed HEK293 cells. The increment in voltage sensitive outward current peaked in $7{\sim}10\;minutes$ after DPDPE application, and the maximum DPDPE-activated outward current $(313.1{\pm}12.3\;pA)$ was recorded when the membrane potential was depolarized to +70mv. Following pretreatment of the transformed HEK293 cells with 1 mM 8-bromo-cyclic AMP, DPDPE failed to increase the voltage sensitive outward currents. On the other hand, naloxone completely abolished DPDPE-activated voltage sensitive outward current in the transformed HEK293 cells. The results of present study suggest that in the transformed HEK293 cells an activation of the ${\delta}-Opioid$ receptors by an opioid agonist DPDPE increases the voltage-sensitive potassium current as a result of decrement in cyclic AMP level.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.4 no.1
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• pp.17-21
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• 1971

The effect of EDTA or BHA pretreatment upon the color preservation of canned surf clam meat during canning and storage was studied. The steamed surf clam meat was soaked in BHA solution, $0.1\%$ BHA in $5\%$ salt solution, or EDTA solution, $0.5\%\;Na_2$ EDTA in $5\%$ salt solution, for 30 minutes. The pretreated surf clam meat was packed in a round enameled can that is 223.2 ml by volume and sterilized for 75 minutes at $110^{\circ}C$. The canned products were stored for one year at room temperature. The EDTA treatment of surf clam meat appeared effective on color preservation during processing. After three month storage, the samples showed little color change comparing with those right after processing. After one year storage, EDTA or BHA treated samples showed better color preservation as compared with control.