• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.275-275
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• 2007

Two sorts of electrode composed of Sulpur/CNT/PVDF and Silver/CNT/PVDF were prepared by in situ chemical method and their electrochemical performance were evaluated by using cyclic voltammetry, impedance measurement and constant-current charge/discharge cycling technique. Also, composite electrodes were characterized by FE-SEM and BET. Raw materials such as CNT/Silver and CNT/Sulfur were mixed in ethanol, dried. These mixed materials were heated at 900 and $320^{\circ}C$ for 2hr, respectively in order to enhance contact among CNT electrodes. Electric double layer capacitor cells were fabricated using these mixed powder with polymer of PVDF. For the charging and discharging characteristics measured at scan rate of 1 mA/s, Supercapacitor of Sulphur-CNT-PVDF electrode showed a better performance than that of Ag-CNT-PVDF, which seems to be related with lower contact resistance of Sulphur-CNT-PVDF electrode.

• Korean journal of food and cookery science
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• v.15 no.4
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• pp.410-417
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• 1999

Antimicrobial activity of Plantain(Plantago asiatica L.) was investigated. Methanol extract of dried Plantain was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as B. subtilis, E. coli, and V. parahaemolyticus at 500 $\mu\textrm{g}$/disc. Ethylacetate fraction was further fractionated into 8 fractions by silica gel column and thin layer chromatography(TLC). The results showed that ethylacetate fractions No. 2 and 3 had the highest anti-microbial activity. They were mixed again, re-separated, and seven fractions were obtained. Among them, No.4 and 6 fraction had the highest inhibitory effect on the microorganisms, which were then separated into four fractions. In the 3rd fractionation, No.4 fraction was identified as hexadecanoic acid by HPLC, $^1$H-NMR and GC-MS.

• Journal of Ecology and Environment
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• v.42 no.4
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• pp.240-258
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• 2018

Background: Several investigations carried out from large brackish lagoons in South Korea. However, no studies have yet examined phytoplankton in lagoons that changed to freshwater, such as Cheonjin Lake. The present study examined the algae from Cheonjin Lake. Methods: Samples were collected at monthly inetrvals from May 2017 to April 2018, from the surface layer using a plankton net (mesh size $20{\mu}m$), and sequeezing submerged macrophytes. Microscopic examinations were conducted at a magnification of 200 to 1000x using a Zeiss microscope (Axio Imager. A2), and photographs were taken with an AxioCam HRC camera. Silica-scaled samples of Chrysophyta for SEM were placed on coverglass, air dried, coated with gold, and then examined with a Hitachi SV8220 SEM. Results: A total of 376 taxa from six major algal groups (Chlorophyta, Chrysophyta, Euglenophyta, Cyanophyta, Dinophyta, and Cryptophyta) were identified. Among these algae, 28 taxa of desmids, 9 taxa of Euglenophyceae, 4 taxa of Chlorophyceae, 2 taxa of Chrysophyceae, and 1 taxon of Xanthophyceae are reported for the first time in Korea. A new species, Cosmarium hexagonum sp. nov was described. The phytoplankton communities were characterized by an abundance of Desmids (within Charophyceae) accounted for 148 taxa from 22 genera. Species richness were particularly high in the Autumn. Conclusion: In this study, a total 376 taxa of 148 desmids (Charophyceae), Chlorophyceae (103 taxa), Chrysophyceae (53 taxa), Euglenophyta (49 taxa), Dinophyta (8 taxa), and Cryptophyta (2 taxa) were identified from Cheonjin Lake. Twenty-eight taxa of desmids including a new species (Cosmarium hexagonum sp. nov.), 9 taxa of Euglenophyceae, 4 taxa of Chlorophyceae, 2 taxa of Chrysophyceae, and 1 taxon of Xanthophyceae were newly recorded in Korea.

• The Korea Journal of Herbology
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• v.32 no.2
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• pp.97-105
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• 2017

Objectives : Gardeniae Fructus is a ripe fruit of Gardenia jasminoides Ellis, which has been used as traditional medicines for anti-inflammatory, diuretic, antipyretic, and antibacterial activity. The aim of this study was to compare of Gardeniae Fructus in South Korea collected during three years according to the standards in monographs of the Korean Pharmacopoeia Eleventh edition (KP11). Methods : 30 items of Gardeniae Fructus from two cultivation regions were classified into dried(n=15) & steamed (n=15) and tested according to the standards in monographs of the KP11. Gardeniae Fructus was carried out identification(comparison of colors, thin layer chromatography), heavy metals, residual pesticides, total ash, and assay registered at KP11. Add to we tested loss on dry, contents of ethanol-soluble extracts, and HPLC profiling. Results : In TLC chromatogram of identification test, the spot of gardenoside and geniposide were observed at $R_f$ value of about 0.3 and 0.5. Heavy metals and residual pesticides met the requirements of the standards for all samples. The results of total ash of each samples are measured maximum 4.87 %. According to HPLC for assay, the samples contain 4.80~6.10 % of geniposide and 0.45~1.83 % of gardenoside. Conclusion : We have verified the current specification standard of Gardeniae Fructus and standard that is not set. By the results, it is proposed a new draft of loss on drying and confirmed the content of gardenoside revised. HPLC standard chromatogram of Gardeniae Fructus is proposed. We hope that it will help the standardization of Gardeniae Fructus.

• Korean Journal of Veterinary Service
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• v.46 no.1
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• pp.1-13
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• 2023

Fatty liver hemorrhagic syndrome (FLHS) is a metabolic disorder found in caged layer hens and causes reduced egg production and sudden death. Dandelion (Taraxacum coreanum, TC) and milk thistle (Cirsium japonicum var. ussuriense, CJ) are well known wild herbs inhabiting Korean peninsula and presenting antioxidative effects. This study investigated alleviate effects of these herbal mixture (6:4, w/w) composed of dried powder of TC and CJ against fatty liver in laying hens. The herbs mixture 5.0, 10.0, 20.0 or 40.0 g/kg feed was provided via feed admixture for 3 weeks to laying hens having FLHS. FLHS was induced by intramuscular injection of β-estradiol (2 mg/kg bw) 2 times per week for 3 weeks and supply with high caloric feed. Egg production rate was reduced from 76.2% at pre-treatment to 49.4% at 1 week and further decreased according to β-estradiol treatment. Increment of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (T-Chol) and total bilirubin (T-Bil) and decrement of serum superoxide dismutase (SOD) and glutathione peroxidase (GPX) with fatty liver were found by the treatment of β-estradiol. Supplementation of TC and CJ mixture via feed admixture recovered the reduction of egg production and attenuated serological changes and gross and pathological lesions of fatty liver with the best amelioration effects at 5 and 10 g TC and CJ mixture per kg feed. In conclusion, TC and CJ mixture attenuates FLHS by means of antioxidative effects. Further mechanistic study is required to explain TC and CJ's amelioration effects against FLHS in laying hens.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.3
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• pp.307-312
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• 1993

Methanol extract of dried persimmon leaves was fractionated to hexane, chloroform, ethyl acetate, butanol, and aqueous tractions. Hexane, butanol, and aqueous fractions had high yields of extracts. Hexane fraction among these fractions showed the highest inhibition rate on the mutagenicities of aflatoxin (AFB$_1$), dimethyl-amino-bi-phenyl (DMAB), N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and 4-nitroquinoline-1-oxide (4-NQO) in Salmonella typhimurium TA100. Hexane fraction was further fractionated into eight fractions by silica gel column c-hromatography and thin layer chromatography (TLC). The fraction 5 on TLC exhibited the highest antimutagenic activity on AFB$_1$, DMAB, and MNNC. 1'-oxocannabinol, 3B-acetoxy-17-methyl-5a-18 (13-17) abeoardrost-13-one, 4-methoxy-2'6'-dinitro-3, 5-di-t-butylbiphenyl, 8, 9-dihydro-5, 6-dimethoxy-dibenz ［c, h］isoquino ［2, 1, 8-1 ma］carbazole-11, 16-dione were tentatively identified from this antimutagenic fraction by GC-MS.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2003.07a
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• pp.309-316
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• 2003

Generally, sesame are dried on the field after being harvested in Korea. Since harvesting season is rainy autumn and sesame drying is mainly affected sun and natural wind, it is difficult to dry sesame in time. Moreover, sesame threshing by hand is very laborious work. Therefore, tractor mounted sesame thresher which threshes sesame bundles fed in upside down and conveyed along threshing bar was developed to mechanize sesame threshing and to reduce labor cost in this research. the thresher was equipped with a threshing bar which beats sesame bundles and a three layer sieve which screens sesame. The results are summarized as follows ; 1 The sesame thresher was consisted of a hitting-stick, a feeding chain conveyor, a threshing bar, conveyor belt, and the three-layer shaking sieve. 2. In threshing test, prototype thresher showed maximum threshing ratio 98.5%, 98.7% at 14, 17 cpm beating rate respectively. 3. In screening test, prototype sieve showed maximum threshing ratio 97.2% at 12$^{\circ}$ of inclined angle and 220 cpm of sieve vibrating rate. 4. Prototype showed 98.7% of threshing ratio, 1.3% of threshing loss, 97.0% of screening ratio, 0.7% of screening loss on the rest condition of 15 sesame bundles/min of feeding rate, 14 cpm of beating rate, 220 cpm of sieve vibrating rate. 5. The working performance of prototype was 0.5hr/10a. It was 9.6 times more efficient than manual work. And, operation cost of prototype was saved by 45.9% compared to manual work.

• The Journal of Korean Academy of Prosthodontics
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• v.45 no.5
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• pp.601-610
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• 2007

Statement of problem: The adhesion between titanium and ceramic is less optimal than conventional metal-ceramic bonding, due to reaction layer form on cast titanium surface during porcelain firing. Purpose: This study characterized the effect of titanium-ceramic adhesion after gold and TiN coating on cast and wrought titanium substrates. Material and method: Six groups of ASTM grade II commercially pure titanium and cast titanium specimens$(13mm{\times}13mm{\times}1mm)$ were prepared(n=8). The conventional Au-Pd-In alloy served as the control. All specimens were sandblasted with $110{\mu}m\;Al_2O_3$ particles and ultrasonically cleaned for 5min in deionized water and dried in air before porcelain firing. An ultra-low-fusing dental porcelain (Vita Titankeramik) was fused on titanium surfaces. Porcelain was debonded by a biaxial flexure test at a cross head speed of 0.25mm/min. The excellent titanium-ceramic adherence was exhibited by the presence of a dentin porcelain layer on the specimen surface after the biaxial flexure test. Area fraction of adherent porcelain (AFAP) was determined by SEM/EDS. Numerical results were statistically analyzed by one-way ANOVA and Student-Newman-Keuls test at ${\alpha}=0.05$. Results: The AFAP value of cast titanium was greatest in the group 2 with TiN coating, followed by group 1 with Au coating and the group 3 with $Al_2O_3$ sandblasting. Significant statistical difference was found between the group 1, 2 and the group 3 (p<.05). The AFAP value of wrought titanium was greatest in the group 5 with TiN coating, followed by the group 4 with Au coating and the group 6 with $Al_2O_3$ sandblasting. Conclusion: No significant difference was observed among the three groups (p>.05). The AFAP values of the cast titanium and the wrought titanium were similar. However the group treated with $Al_2O_3$ sandblasting showed significantly lower value (p<.05).

• Korean journal of food and cookery science
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• v.16 no.5
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• pp.445-452
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• 2000

Antimicrobial activity of Jakyak(Paeonia japonica var. pilosa $N_{AKAI}$) was investigated. Methanol extract of dried Jakyak was fractionated to hexane, chloroform, ethylacetate, butanol and aqueous fraction. Ethylacetate fraction among these fractions showed the highest inhibitory effect on the microorganisms such as B. subtilis, L. monocytogenes, and V. parahaemolyticus at 500 $\mu\textrm{g}$/disc. Ethylacetate fraction was further fractionated into 11 fractions by silica gel column and thin layer chromatography(TLC). The results showed that ethylacetate fractions No. 3, 4 and 5 had the highest antimicrobial activity. They were mixed again, re-separated, and 5 fractions were obtained. Among them, the highest inhibitory effect was obtained in No. 3 fraction, which was identified as cetyl alcohol by HPLC and GC-MS.S.

• Restorative Dentistry and Endodontics
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• v.25 no.2
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• pp.243-253
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• 2000

The purpose of this in vitro study was to evaluate dentin bonding by two different dentin bonding systems(DBS) using acetone based primer or adhesive [All Bond 2(AB2), One Step(OS)] when they were applied by wet or dry bonding technique. Morphology of resin-dentin interface and hybrid layer thickness(HLT) were investigated using Confocal Laser Scanning Microscope(CLSM) and compared to shear bond strength(SBS). 72 extracted sound human molars were randomly divided into 4 groups of 18 teeth each - Group 1.(AW); AB2 by wet bonding. Group 2(AD); AB2 by dry bonding. Group 3.(OW); OS by wet bonding, Group 4.(OD); OS by dry bonding. In 6 teeth of each group, notch-shaped class V cavities(depth 2mm) were prepared on buccal and lingual surface at the cementoenamel juction(12 cavities per group). To obtain color contrast in CLSM observation, bonding resins of each DBS were mixed with rhodamine B and primer of AB2 was mixed with sodium fluorescein. Prepared teeth of each group were treated with AB2, OS, respectively according to the manufacturer's instructions except for dentin surface moisture treatment after acid etching. In group 1 and 3, after acid etching, excess water was removed with wet tissue(Kimwipes), leaving consistently shiny, visibly hydrated dentin surface. In group 2 and 4, dentin surface was dried for 10 seconds at 1 inch distance. The treated teeth were then packed with composite resin(${\AE}$litefil) and light-cured. 12 microscopic samples($60{\sim}80{\mu}m$ thickness) of each group were obtained after longitudinal section and grinding(Exakt cutting and grinding system). Morphological investigation of resin-dentin interface and HLT measurement using CLSM were done. For measurement of SBS, remaining 12 teeth of each group were flattened occlusally to remove all enamel and grinded to 500 grit SiC(Pedemet Specimen Preparation Equipment). After applying DBS on the exposed dentin surface, composite resin was applied in the shape of cylinder, which has 5mm diameter, 1.5mm thickness, and light cured. SBS was measured using Instron with a crosshead speed of 0.5mm/min. It was concluded as follows, 1. HLT of AW(mean: $2.59{\mu}m$) was thicker than any other group, and followed by AD, OW, OD in descending order(mean; 2.37, 2.28, $1.92{\mu}m$). Only OD had statistically significant differences(p<0.05) to AW and AD. 2. There were intimate contact of resin and dentin at the interface in wet bonding groups, but gaps or irregular interfaces were observed in dry bonding groups. 3. The length, diameter, density of resin tags were various even in the same group without significant differences between groups and lots of adhesive lateral branches were observed. 4. There were no statistically significant difference of SBS between AB2 and OS, but SBS of wet bonding groups were significantly higher(p<0.05) than dry bonding groups. 5. There were no consistent relationships between HLT and SBS.