• Elastomers and Composites
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• v.52 no.2
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• pp.143-153
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• 2017

Herein we studied the characterization of the PBO films formed via solution casting and thermal cyclization of poly(o-hyroxyamide)s(PHAs) that were synthesized by direct polycondensation of 3,3'-dihydroxybenzidine with 4,4'-(2,3-quinoxalinedioxy) dibenzoic acid and/or 4,4'-(2,3-pyridinedioxy) dibenzoic acid. All the PHAs exhibited inherent viscosities in the range of 0.55~0.84 dL/g in DMAc solution. The copolymers, CPH-2-5, were partially soluble in less polar solvents like pyridine and THF. However, all the PBOs were not soluble in polar solvents, but only partially soluble in sulfuric acid. The temperatures corresponding to 10% weight loss of the PBOs with increasing content of quinoxalinedioxy unit were higher than those of the PHAs, and the char yields at $900^{\circ}C$ in $N_2$, tensile strength, and initial modulus of the PBOs were 1.1~1.3 times, 1.2~1.8, and 1.6~3.3 times higher, respectively, than those of the PHAs. The LOI value of CPB-2 was 38.5%, while that of CPB-1 was the highest at 40.0%. The LOI test confirmed that excellent flame retardants were synthesized.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.5
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• pp.649-658
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• 2012

In this study, the influencing factors for efficient anaerobic digestion of high strength ammonia-nitrogen wastewater removal were investigated by testing biochemical methane potential test. In the influencing factors, the trace metals which could increase activity of anaerobic microorganisms, microbial concentration and types were evaluated. In the results, trace metals supplementation showed gas production amount higher than those without addition of trace metals. Among the tested trace metals, B, Ni, and Se were preferable to gas production. In the result of gas production according to the microbial concentration, the amount of gas production was proportional to the microbial concentration. In addition, the shortest lag time and the fastest gas production rate were achieved when the highest microbial concentration was tested. granule-type microorganism produced more gas than suspended-type microorganism. In conclusion, the efficient anaerobic digestion for high strength ammonia-nitrogen wastewater removal could be achieved by applying necessary trace metals injection and high concentration granule type microorganism.

• Journal of Korean Society of Water and Wastewater
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• v.28 no.1
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• pp.55-60
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• 2014

Food waste leachate (FWL) is a serious pollutant waste coming from the food waste recycling facilities in Korea. FWL has a high organic matter content and high COD to nitrogen (COD/N) ratio, which can disturb efficient methane production in the anaerobic digestion of FWL. In the present study a microalga, Clorella vulgaris (C.V), was used as co-substrate for the FWL anaerobic digestion in order to supply nutrients, decrease the COD/N ratio and increase its methane yield. Different co-digestion mixtures (COD/N ratios) were studied by using biochemical methane potential test and modified Gompertz equation for kinetic study. Mixed substrate of FWL and C. vulgaris in the co-digestion clearly showed more the biomethane yield than the sole substrates. The maximum methane production, 827.7 mL-$CH_4$/g-VS added, was obtained for COD/N ratio of 24/1, whereas the highest improvement of methane yield was found for COD/N ratio of 15/1.

• The Journal of Korean Medicine
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• v.23 no.2
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• pp.139-150
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• 2002

OBJECTIVES : Schizandra chinensis is well known for its efficacy at liver function reinforcement, relieving thirst and recovery from fatigue. In this study, we examined the effects of sports drink containing Schizandra chinensis on serum metabolic substrate, electrolyte, stress indicators, related-enzyme and exercise performance, rectal temperature, and heat shock proteinb70 (HSP70). METHODS : Elite long-distance runners (male, 21.3yrs, n=16) were selected and divided into two groups; an experimental group (EXP, n=8) and a control group (CON, n=8). A beverage containing Schizandra chinensis was supplemented 3 times per day to EXP for 4 weeks. Serum biochemical elements (glucose, lactate, total cholesterol, triglyceride, high density lipoprotein cholesterol, glutamate oxaloacetate transaminase, glutamate pyruvate transaminase, creatinine, creatine phosphokinase, lactate dehydrogenase, blood urea nitrogen, Na, K, Cl) were analyzed by auto blood analyzer. Exercise performance was measured by treadmill exercise test, HSP70 was detected by electrophoresis and Western blotting, and rectal temperature was measured by rectal temperature probe. RESULTS : Administration of the beverage increased significantly the rest level of blood Na, Cl and glucose and decreased significantly lactate dehydrogenase, glutamate oxaloacetate transaminase. No difference was found in exercise performance, rectal temperature increment or HSP70 concentration between groups. CONCLUSIONS : Administration of a sports drink containing Schizandra chinensis altered blood glucose, lactate dehydrogenase, glutamate oxaloacetate transaminase, Na and Cl levels.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.514-517
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• 2009

Anaerobic biodegradability(AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical Methane Potential(BMP) test has been carried out to evaluate the methane yield of agro-industrial biomasses such as cattle manure, Italian ryegrass(IRG), Oats, Rye and Barley as the forage crops, Rush, the sludges produced from milling and slaughterhouse wastewater treatment plant(SMWTP, SSWTP). In the condition of thermophilic anaerobic digestion, the ultimate methane yield and anaerobic biodegradability of forage crops ranged from 0.367 to $0.452LCH_4$/gVS of methane yield with AB having the range of about 77.0 to 87.3%. On the other hand, that of other substrate showed low figures compared with the forage crops because of low VS content and C/N ratio. Therefore, the forage crops could be used as a good substrate to produce much more the methane in anaerobic digestion.

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.79-82
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• 2008

Anaerobic biodegradability(AB), which can be determined with the ultimate methane yield by the decomposition of organic materials, is one of the important parameters for the design and the operation of anaerobic digestion plant. In this study, Biochemical Methane Potential(BMP) test has been carried out to evaluate the methane yield of animal manures, such as pig and cattle slurries, and different forage crops cultivated at the reclaimed tideland, such as maize, sorghum, barley, rye, Italian ryegrass(IRG), rape, rush and sludge produced from slaughterhouse wastewater treatment plant(SWTP). In the ultimate methane yield of animal manure, that of pig slurry(no used a EM) was 407 $mlCH_4/gVS_{fed}$ higher than 242 $mlCH_4/gVS_{fed}$ of cattle slurry. The ultimate methane yield of spike-crop rye was 442.36 $mlCH_4/gVS_{fed}$ the highest among different forage crops, the other showed the value above a methane yield of 300 $mlCH_4/gVS_{fed}$. The forage crop could be used as a good substrate to improve the methane production in anaerobic co-digestion together with animal manure.

• Journal of Animal Science and Technology
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• v.62 no.1
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• pp.74-83
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• 2020

Organic waste used as a feedstock in the anaerobic digestion (AD), it includes carbon and nitrogen. Carbon and nitrogen have an effect on the various digestive characteristics during AD, however, the study is rare about those of the interaction. This study investigates the influence of carbon type and carbon to nitrogens (C/N ratios) on the AD characteristics of organic waste. Experimental treatments involved a combination of three carbon types with three C/N ratios. The AD tests were carried out using a 125-mL serum bottle at a constant temperature of 37℃ and moisture 95% for 18 days. Degradation pattern shows the difference among three-carbon treatments, the starch group was faster than other groups. Maximum methane production date was similar between starch (9.96 ± 0.05 day) and xylan group (10.0 ± 0.52 day), those of the cellulose group (14.6 ± 1.80 day) was slower than other groups (p < 0.05). The lag phase was only affected by the carbon type (p < 0.05). Ammonia nitrogen was mainly affected by nitrogen concentration regardless of carbon type (p < 0.05). This study showed that xylan is useful as feedstock in order to decrease the lag phase, and it showed that ammonia was independently affected by the nitrogen concentration.

• Korean Journal of Veterinary Service
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• v.34 no.3
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• pp.209-216
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• 2011

This study carried out to investigate the pathogenic Streptococcus spp. isolated from respiratory tract of Thoroughbred in Jeju province. The specimens were collected from nasal mucosa using a culture swab from 113 Thoroughbred horses. Suspected colonies were selected onto blood and MacConkey agar plate, and identified by standard biochemical properties using Vitek 2 system and PCR method. In this study, we isolated S. equi (n=6), S. zooepidemicus (n=31), S. equisimilis (n=5), S. dysgalactiae (n=2), S. agalctiae (n=1), non identified ${\beta}$-hemolytic Streptococcus spp. (n=1) from Thoroughbred horses. In antimicrobial susceptibility test, it showed a high sensibility in the most of antimicrobial except for neomycin, streptomycin, spectinomycin, erythromycin and clindamycin. These results will provide the basic information to establish control measures for the treatment and prevention of respiratory disease by pathogenic Streptococcus spp. in Thoroughbred horses in Korea.

• The Korean Journal of Mycology
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• v.37 no.2
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• pp.181-188
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• 2009

A Gram-positive, rod-shaped bacteria named DY5 was isolated from a peat sample collected from Daeam mountain in Korea. The culture filtrate of the bacterial isolate DY5 showed a broad spectrum of antifungal activity on various crop pathogenic fungi such as Trichoderma koningii, Fusarium oxysporum, Colletotrichum gloeosporioides, Sclerotinia sclerotiorum, Rhizoctonia solani AG-1(IA) For the identification of the DY5, morphological, biochemical, API 50 CHB test, analysis of fatty acid and molecular phylogenetic approaches were performed. The DY5 was found to be a member of the genus Paenibacillus on the basis of morphological and biochemical analysis. The 16S rRNA of DY5 showed high similarity(98%) with Paenibacillus polymyxa. On the basis of these results, the DY5 was identified as Paenibacillus polymyxa. Antifungal substance of the DY5 would be mild alkaline proteine molecule. The DY5 seems to have a great potential to be a biocontrol agent against various crop pathogens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.218-223
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• 2000

The objective of this study was to investigate the effectiveness of preservatives for extending storage life and maintaining the quality of minimally processed Chinese cabbage. Cut Chinese cabbage was treated with either 1% CaCl2, 1% NaCl, 3% sucrose, 1% Ca-lactate, 1% vitamin C, 0.05% chitosan＋1% vitamin C, 0.1% Sporix＋1% vitamin C or hot water(6$0^{\circ}C$) and then packed with polyethylene film(60${\mu}{\textrm}{m}$) and stored at either 2$0^{\circ}C$ or 4$^{\circ}C$. To evaluate biochemical changes and quality of minimally processed Chinese cabbage, the samples were tested to determine the amount of vitamen C, titratable acidity, organic acid and fiber contents. Changes in color were also examined. The quality of kimchi prepared form minimally processed cabbage was affected by the treatments. REsults indicate that the minimally processed Chinese cabbage treated with either 1% CaCl2 at 2$0^{\circ}C$ and 4$^{\circ}C$ or 1% NaCl at 2$0^{\circ}C$ minimized biochemical changes in plant tissue and those treatments were most effective in maintaining product quality. The cabbage treated with 1% vitamin C or 1% NaCl at 4$^{\circ}C$ resulted in kimchi with improved color, texture, flavor and the best overall acceptability, as determined by a sensory test.