• Natural Product Sciences
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• v.11 no.2
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• pp.92-96
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• 2005

The antifungal activities of essential oils from the leaves of Glehnia littoralis, which is cultivated in Korea, were evaluated against pathogenic Trichophyton species by the broth dilution method and the disk diffusion test. Additionally, the effects of the oils together with ketoconazole were tested by the checkerboard titer test. The essential oil fraction and its main components showed significant inhibition of the tested Trichophyton fungi, with minimal inhibitor concentrations (MICs) in the range of 16-32 mg/ml. The results suggest that activities of this oil are based mainly on the contents of ${\alpha}-pinene$ (22.17%), the next prominent component of the oil fraction, while the first main components ${\beta}-pinene$ (57.83%) have relatively mild activity. The MICs of ${\alpha}-pinene$ and ${\beta}-pinene$ were 1-4 mg/ml and 4-32 mg/ml, respectively. Additionally the Glehnia oil fraction and its main components as well, exhibited significant synergism with ketoconazole against Trichophyton rubrum.

• YAKHAK HOEJI
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• v.46 no.3
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• pp.203-207
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• 2002

The antifungal activities of the essential oils from Anthemis nobilis, Ciderus atlantica, Juniperus communis, Lavandula angustifolia, Pelargonium graveolens, Pogestemon patchouli, Rosmarinus officinalis, and Styrax tonkinensis which are recommended for the treatment of microbial infections in aromatherapy and complementary medicines were tested against Candida spp. The activities were measured by broth dilution method and disk diffusion assay. Most of the test oils inhibited growth of Candida albicans, C. utilis and C. tropicalis. Especially, the essential oil from Pelargonium graveolens and its main component, citronellol showed the strongest activity among the herbs except benzoic acid from Styrax tonkinensis which is well-known antimicrobial compound. As a result of checkerboard microtiter test. synergistic effect of citronellol, was shown when the component was combinated with ketoconazole, displaying a fractional inhibiting concentration (FIC) index of 0.37 against C. albicans.

• Elastomers and Composites
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• v.51 no.1
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• pp.43-48
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• 2016

Multi-Surface (MS) treatment is a new technique of surface treatment to reduce the static friction factor on the surface of rubber. MS treatments include 4 methods which names are MS-V (UV-irradiation on the rubber surface), MS-M (doing the chemical reaction with double bond of rubber), MS-Q (dilution of rubber surface by silicone surfactant), and MS-P (coating and heating of rubber surface). The experiment and test of every MS-treatment had been carried out using acrylonitrile-butadiene rubber (NBR), ethylene-propylene-diene rubber (EPDM), and chlorosulphonated rubber (CSM) as rubber materials. It had introduced the steps of every MS-treatment process and the result of the properties test. From the research, it was found that the best method was MS-V treatment because it suited all the samples and the effect was obviously.

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.765-769
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• 2005

The essential oil fraction of Ostericum koreanum was analyzed by GC-MS. Inhibiting activities of this oil and its main components were tested by the broth dilution assay and disk diffusion test against one antibiotic-susceptible and two resistant strains of Salmonella enteritidis and S. typhimurium, respectively. The GC-MS analysis revealed thirty-four compounds; the main components were $\alpha$-pinene (41.12%), $\rho$-cresol (17.99%) and 4-methylacetophenone (7.90%). The essential oil of O. koreanum and its main components were significantly effective against the tested antibiotic-susceptible strains as well as against the resistant strains of the two Salmonella species, with MICs (minimum inhibitory concentrations) ranging from 2 mg/mL to 16 mg/mL. The anti-Salmonella effects of the oils were dose-dependent on $M\"{u}ller-Hinton$ agar plates in this experiment. Additionally, checkerboard titer test results demonstrated significant combined effects of streptomycin and O. koreanum oil or cresol, one of the main components of this oil, against the two streptomycin resistant strains of S. typhimurium, with FICIs ranging from 0.12 to 0.37.

• Korean Journal of Veterinary Research
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• v.25 no.1
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• pp.49-51
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• 1985

A serological survey for antibodies to Leptospira (L.) interrogans in dairy and Korean native cattle in Gyeongbuk area was performed using 6 different living antigens, which were L. icterohaemorrhagiae(RGA), L. canicola(Hond Utrecht IV), L. autumnalis(Akiyami A), L. australis(Ballico), L. pomona(Pomona) and L. hebdomadis(Hebdomadis), by microscopic agglutination test. In the microscopic agglutination test, greater than partial agglutination at a serum dilution of 1:300 or over was recorded as positive. In the dairy cattle(Holstein), four(4.7%) of 86 sera from 13 dairy farms were positive for L. canicola and L. pomona antibodies. In the Korean native cattle, four(3.2%) of 124 sera from the slaughter house in Taegu city were positive for L. canicola, L. icterohaemorrhagiae and L. pomona antibodies. Among the positive sera, L, canicola was dominated in this experiment.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.840-845
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• 2001

Development of a small gas-turbine combustor for 100kW class APU(Auxiliary Power Unit) has been performed. This combustor is a reverse-annular type and has a tangential swirler in the liner head to improve the fuel/air mixing and flame stability. Three main and three pilot fuel injectors of the simplex pressure-swirl type are used. The performance target at the design condition includes a turbine inlet temperature of 1170K, a combustion efficiency of 99%, a pattern factor of 30%, and an engine durability of 3000 hours. Under developing the combustor, we conducted performance test of our first prototype(TS1) with some variants. As a result of the test, the performance targets of the combustor are satisfied except that the pattern factor is about 4% higher than target value. So, we redesigned the second prototype(TS2) and conduct performance test with the critical focus on pattern factor and exit mean temperature. We adopted TS2 four variant to check the improvement of pattern factor. As the result, the pattern factors of several variants were satisfied with the performance target. Finally, We chose the TS2A variant as a final combustor for our APU model.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.22 no.6
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• pp.840-848
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• 1998

The preliminary design and performance test were carried out for determining dimensions of gas turbine combustor. The combustor design program was developed and applied to design our combustor, and the specific dimensions for swirler, dome and liner holes were determined by the semiempirical manner. Based on the first performance test data, the swirl angle governing the combustion characteristics of primary combustor zone was determined as 40 deg.. Using the second performance test data, the swirler dimensions were readjusted by 24 mm i.d., 34 mm o.d., and swirl angle of 45 deg.. The geometry of liner holes were determined by considering the flame stability and recirculation zone size. It was found that flame can be more easily stabilized by adjusting the swirler dimensions rather than liner holes. The geometry of swirler and liner holes were readjusted by using the final performance test data with dilution holes. Also, the combustor performance and emission characteristics were evaluated by analysis of exhaust gases.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.2
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• pp.22-27
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• 2017

During the water treatment process for household water supply, a reservoir is the last place the water is stored before being supplied to users, and the duration of the water's stay is an important factor that affects its safety. This may cause the concentration of the residual chlorine disinfectant to increase and thus lower the water's quality. The concentration and discharge efficiency of residual chlorine must be verified and managed, because these are key factors that affect the reservoir's performance. Because the actual verification test for analyzing the efficiency of a reservoir and the disinfectant's dilution capacity is difficult, simulations are generally conducted using the computational fluid analysis method. However, the simulation results require validation with experiments. The error and drainage efficiency were analyzed in this study by comparing and analyzing the actual tracer test and simulation so that the actual test for a hexagonal drainage can be replaced by the computational fluid analysis method. Based on the results of the efficiency analysis, the hexagonal reservoir was found to be appropriate, and the simulation's reliability was verified with a tracer test.

• Journal of Food Hygiene and Safety
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• v.11 no.4
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• pp.299-306
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• 1996

6-[(N-3,4-Dibromophenyl)amino]-7-chloro-5,8-quinolinedione(FCK13) was tested for antifungal activities. The MIC values were determined by the two-fold dilution method. The therapeutic potential of RCK13 had been assessed in comparison with ketoconazole and fluconazole against systemic infections with candida albicans in normal mice. RCK13 had ED50,0.80$\pm$0.21 mg/kg but ketoconazole had ED50, 8.00$\pm$0.73 mg/kg respectively. And administered RCK13 at the ED50 for 14 days improved survival rates as well as ketoconazole. Acute oral toxicity studies of RCK13 were carried out in ICR mice of both sexes. These acute oral toxicities of RCK13 were low and LD50 values were over 2,850 mg/kg in ICR mice. The genotoxicities of RCK13 had been evaluated. RCK13 was negative in Ames test with Salmonella typhimurium and chromosomal aberration test in CHL cells. The clastogenicity was tested on the RCK13 with in vivo mouse micronucleus assay. RCK13 did not show any clastogenic effect in mouse peripheral blood and was negative in mouse micronucleus assay. These results indicate that RCK13 has no genotoxic potential under these experimental conditions.

• Research in Plant Disease
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• v.7 no.3
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• pp.170-174
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• 2001

Gelatin particle agglutination test (GPAT) was optimized for detection of Tobamovirus and contamination of the virus in commercial pepper seeds was evaluated. The optimum concentration of ${\gamma}$-globulin G, specific to tobacco mosaic virus pepper strain, was 100 ug/ml. The sensitivity of GPAT for the detection of Tobamovirus in pepper seeds was as high as enzyme-linked immunosorbent and dot immunoblotting assays. Optimum dilution ranges of the seed extract for GPAT was 5-25 folds. Using the optimized GPAT with above conditions, the rate of Tobamovirus contamination in seeds was turned out to be average of 79.1%.