• Korean Chemical Engineering Research
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• v.53 no.3
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• pp.391-396
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• 2015

To investigate the effect of the catalyst synthesis method on the oxidative dehydrogenation (ODH) of nbutenes, $BiFe_{0.65}MoP_{0.1}$ oxide catalysts were prepared with various synthesis methods such as co-precipitation, citric acid method, hydrothermal method, and surfactant templated method. The catalysts were characterized by X-ray Diffraction (XRD), $N_2$ sorption, and $NH_3/1$-butene-temperature programmed desorption ($NH_3/1$-butene-TPD) to correlate with catalytic activity in ODH reaction. Among the catalysts studied here, $BiFe_{0.65}MoP_{0.1}$ oxide catalyst prepared with co-precipitation method marked the highest activity showing 1-butene conversion, 79.5%, butadiene selectivity, 85.1% and yield, 67.7% after reaction for 14 h. From the result of $NH_3$-TPD, the catalytic activity is closely related to the acidity of the $BiFe_{0.65}MoP_{0.1}$-x oxide catalyst and acidity of the $BiFe_{0.65}MoP_{0.1}$ oxde catalyst prepared with co-precipitation method was higher than that of other catalysts. In addition, combined with the 1-butene TPD, the higher catalytic activity is closely related to the amount of weakly adsorbed intermediate (< $200^{\circ}C$) and the desorbing temperature of strongly adsorbed intermediates (> $200^{\circ}C$).

• Tuberculosis and Respiratory Diseases
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• v.41 no.4
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• pp.397-404
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• 1994

Background: To decide the optimal antibiotics and application of chest tube, examination of pleural fluid is fundamental in the management of empyema. Some criteria for drainage of pleural fluid have been recommended but some controversies have been suggested. Recently, newer radiologic methods including ultrasound and computed tomography scanning, have been applied to the diagnosis and management of pleural effusions. We undertook a retrospective analysis of 30 patients with pleural effusion who had CT scans of the chest in order to apply the criteria of Light et al retrospectively to patients with loculation and to correlate the radiologic appearance of pleural effusions with pleural fluid chemistry. Method: We analyzed the records of 30 out of 147 patients with pleural effusion undergoing chest CT scans. Results: 1) Six of the pleural fluid cultures yielded gram negative organisms and three anaerobic bacterias and one Staphylococcus aureus and one non-hemolytic Streptococci. No organism was cultured in ninteen cases(63.0%). 2) The reasons for taking chest CT scans were to rule out malignancy or parenchymal lung disease(46.7%), poor response to antibiotics(40.0%), hard to aspirate pleural fluid(10.0%) and to decide the site for chest tube insertion(3.3%). 3) There was no significant correlations between ATS stages and loculation but there was a tendency to loculate in stage III. 4) There was a significant inverse relationship between the level of pH and loculation(p<0.05) but there appeared to be no relationship between pleural fluid, LDH, glucose, protein, loculation and pleural thickening. 5) In 12 out of 30, therapeutic measures were changed according to the chest CT scan findings. Conclusion: We were unable to identify any correlations between the plerual fluid chemistry, ATS stages and loculations except pH, and we suggest that tube thoracotomy should be individualized according to the clinical judgement and serial observation. All patients with empyema do not need a chest CT scan but a CT scan can provide determination of loculation, guiding and assessing therapy which should decrease morbidity and hospital stay.

• Transactions of the Korean hydrogen and new energy society
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• v.26 no.4
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• pp.339-346
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• 2015

The synthesis of Fischer-Tropsch (FT) oil is the catalytic hydrogenation of CO to give a range of products, which can be used for the production of high-quality diesel fuel, gasoline and linear chemicals. This studied catalyst was prepared Cobalt-supported alumina and silica by the incipient wet impregnation of the nitrates of cobalt, promoter and organic solvent with supports. Cobalt catalysts were calcined at $350^{\circ}C$ before being loaded into the FT reactors. After the reduction of catalyst has been carried out under $450^{\circ}C$ for 24h, FT reaction of the catalyst has been carried out at GHSV of 4,000/hr under $200^{\circ}C$ and 20atm. From these experimental results, we have obtained the results as following; In case of $SiO_2$ catalysts, the activity of 12wt% $Cobalt-SiO_2$ synthesized by organic solvent was about 2 or 3 times higher than the activity of 12wt% $Cobalt-SiO_2$ catalyst synthesized without organic solvent. In particular, the activity of the $Cobalt-SiO_2$ catalyst prepared in the presence of an organic solvent P was two to three times higher than that of the $Cobalt-SiO_2$ catalyst prepared without the organic solvent. Effect of Cr and Cu metal as a promoter was found little. 200 h long-term activity test was performed with a $Co/SiO_2$ catalyst prepared in the presence of an organic solvent of Glyoxal solution.

• Journal of Life Science
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• v.28 no.7
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• pp.835-840
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• 2018

Quantitative determination of the protein expression levels is one of the most important parts in assessment of the safety of foods derived from genetically modified (GM) crops. Overexpression of AtCYP78A7, a gene encoding cytochrome P450 protein, has been reported to improve tolerance to abiotic stress, such as drought and salt stress, in transgenic rice (Oryza sativa L.). In the present study, an enzyme-linked immunosorbent assay (ELISA) kit for diagnosing AtCYP78A7 protein including AtCYP78A7-specific monoclonal antibody was developed. GST-AtCYP78A7 recombinant protein was induced and purified by affinity column. Four monoclonal antibodies (mAb 6A7, mAb 4C2, mAb 11H6, and mAb 7E8) against recombinant protein were also produced and biotinylated with avidin-HRP. After pairing test using GST-AtCYP78A7 protein and lysate of rice samples, mAb 4C2 and mAb 7E8 were selected as a capture antibody and a detecting antibody, respectively, for ELISA kit. Product test using rice samples indicated that percentages of detected protein in total protein were greater than 0.1% in AtCYP78A7-overexpressing transgenic rice (Line 10B-5 and 18A-4), whereas those in negative control non-transgenic rice (Ilpum and Hwayoung) were less than 0.1%. The ELISA kit developed in this study can be useful for the rapid detection and safety assessment of transgenic rice overexpressing AtCYP78A7.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.315-318
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• 1994

To obtain transformed plants, we cocultured cotyledonary explants of Codonopsis lanceolata with Agrobacterium tumefaciens LBA4404, a disamed strain harboring a binary vector pBI121 carrying the CaMV35S promoter-$\beta$-glucuronidase (GUS) gene fusion used as a reporter gene and NOS promoter-neomycin phosphotransferase gene as a positive selection marker in MS liquid medium with 1mg/L BA. After 48 h of culture, explants were transferred onto MS solid medium with Img/L BA, 250mg/L carbenicillin, and 100mg/L kanamycin sulfate and cultured in the dark. Numerous adventitious buds formed on the cut edges of the explants after 2 weeks of culture. When subjected to GUS histochemical assay buds showed a positive response at a frequency of 15%. Explants formed adventitious shoot at a frequency of 56.7%, after 6 weeks of culture. Upon transfer onto the basal medium, most of the shoots were rooted and subsequently the regenerants were transplanted to potting soil. Southern blot analysis confirmed that the GUS gene was incorporated into the genomic DNA of the GUS-positive regenerants.

• Applied Chemistry for Engineering
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• v.22 no.2
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• pp.155-160
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• 2011

An animal fat is an attractive biodiesel energy source for its high stability against oxidation and low incomplete combustion ratio due to the high heating value and cetane value. However, it requires a refinery process because of the high content of saturated acid and impurity which increas the boiling point. In this study, the optimum biodiesel synthetic process of lard is suggested. Indeed, we demonstrate new biodiesel production processes to alter conventional process of heating and mixing by applying ultrasonic energy. While the optimum reaction temperature and mole ratio of methanol and lard, when using conventional mixing and heating process, were $55^{\circ}C$ and 12, respectively, the reaction time were reduced to 30 minutes by applying ultrasonic irradiation power of 500 W. The new process applying ultrasonic irradiation yielded synthetic biodiesel properties as followings: 3.34 cP of the viscosity, 37.0 MJ/kg of the caloric value and below 0.25 mgKOH/g of the acidic value, which satisfy biodiesel quality criteria.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1363-1368
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• 2008

The extraction and quantitative analysis conditions for astaxanthin from Haematococcus pluvialis, and the structural characteristics of H. pluvialis extract, H. pluvialis hydrolysate and synthetic astaxanthin were investigated using UV/visible and FT-IR spectrometers. Astaxanthin was dissolved in methanol, and then treated to enhance the solubility by sonication for 45 min. With sonication pretreatment, the solubility of astaxanthin increased up to 1.5 times compared to that without sonication. The extracts were hydrolyzed by cholesterol esterase for the analysis of H. pluvialis extract containing astaxanthin ester. A HPLC method using reverse phase C18 column with methanol-water (95:5, v/v) as mobile phase was developed to analyze astaxanthin. After hydrolysis, the absorption spectrum of H. pluvialis hydrolysat was changed to similar pattern to synthetic astaxanthin, confirming the extraction and analysis condition of astaxanthin from H. pluvialis.

• Microbiology and Biotechnology Letters
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• v.26 no.4
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• pp.323-330
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• 1998

Cyclodextrin glucanotransferase (CGTase) was purified from the culture broth of the Bacillus firmus var. alkalophilus, using ultrafiltration, starch adsorption/desorption, ion-exchange chromatography on DEAE-cellulose and gel filtration on Sephacryl HR-100. The molecular weight of the purified enzyme was determined as 77,000 by SDS-PAGE. The optimum pH and temperature for the CD synthesis were 6.0 and 5$0^{\circ}C$, respectively. The activity of this enzyme was stably kept at the range of pH 6.0～9.5 and up to 5$0^{\circ}C$. However, in the presence of $Ca^{2+}$, the optimum temperature for CD synthesis was shifted 55~6$0^{\circ}C$ and this enzyme was stable up to 6$0^{\circ}C$ because of the stabilizing effect of $Ca^{2+}$. The purified CGTase produced CDs with high conversion yields of 45~51% from sweet potato starch, com starch and amylopectin as substrate, especially, and the product ratio of $\beta$-CD to ${\gamma}$-CD was obtained at range of from 5.8:1 to 8.4:1 according to the kind of substrate. The purified enzyme produced mainly $\beta$-CD without accumulation of $\alpha$-CD during enzyme reaction using various starches as the substrate, indicating that the purified enzyme is the typical $\beta$-CGTase. The purified CGTase produced 25 g/l of CDs from 5.0% (w/v) liquefied com starch and the conversion yield of CDs was 50%, and the content of $\beta$-CD was 84% of total CDs after 8 hours under the optimum reaction condition.ion.

• Journal of the Korea Organic Resources Recycling Association
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• v.11 no.4
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• pp.105-113
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• 2003

Successful operation of a reactor can be accomplished when it is operated at proper D depending on the state of degradation. Operation at high D leads to the washout of biomass in the reactor while operation at low D leads to product inhibition due to the accumulation of excess VFA. These appear to limit the production of hydrogen to reach a higher level. Operation by D control was performed to improve the efficiency of hydrogen fermentation of food waste. Although simple organic matters were rapidly degraded in the early stage (day 1-2), proper VFA concentration and pH values were kept in the reactor at D of $4.5d^{-1}$, which was previously reported to be optimum initial D. High butyrate/acetate (B/A) ratios over 3.2 were obtained. Without D control, the reduction of simple organic matters after day 2 caused the decrease of VFA production and the increase of pH. Hydrogen production also decreased, as microbial proliferation was less than microbial loss by washout. However, the reactor performance was dramatically improved at D control from 4.5 to $2.3d^{-1}$. It showed the highest B/A ratios over 2.0 among the reactors on day 4-7. The second hydrogen peak appeared on day 4, resulting in the highest fermentation efficiency (70.8%) among the reactors. It was caused by the enhanced degradation of slowly degradable matters. The COD removed was converted to hydrogen (19.3%), VFA (36.5%), and ethanol (15.0%). Therefore, the strategy using D control, depending on the state of degradation, was effective in improving the efficiency of hydrogen fermentation.

• Journal of the Korean Wood Science and Technology
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• v.38 no.3
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• pp.251-261
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• 2010

Cellulase from Formiptosis pinicola KMJ812 is an efficient cellulose degradation enzyme complex, especially with a high ${\beta}$-glucosidase activity. In this study, the change in enzymatic characteristics by immobilization and the reduction of immobilized enzyme activity by repeated usages were evaluated using cellulases from F. pinicola KMJ812. Among tested four resins, Duolite A568 resin had the best enzyme activity yield with 61.7% cellulase activity and 64.4% ${\beta}$- glucosidase activity during the cellulase immobilization. The best reaction temperature was $55^{\circ}C$ for both cellulase and ${\beta}$-glucosidase activities which were higher than the unimmobilized soluble cellulases. The best reaction pH was 4.0 for cellulase activity which was a little more basic than a soluble form and 4.5 for ${\beta}$-glucosidase activity. The immobilized cellulase activity was remained 98% of the beginning activity after 72 h incubation at $50^{\circ}C$ and 50% of the beginning activity after eight times usage at $50^{\circ}C$.