• Asian Journal of Turfgrass Science
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• v.15 no.4
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• pp.157-168
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• 2001

This study was carried out to investigate the offsets of pyroligneous acid on the growth of ‘Penncross’Creeping Bentgrass (Agrostis palustris Huds.) and to propose the practical use for ecologically responsive management in Korean golf courses. In the plots affected by 300, 500, and 800 times diluted pyroligneous acid, the turfgrass growth increment and the visual quality were measured at fixed periods. The data were subjected to paired samples T-test. The results summarized are as follows； 1) In leaf growth increment, density, and root spread depth, turfgrass affected by 500 and 800 times diluted pyroligneous acid were superior to the control continually. It was reliable in the statistics. Especially, 500 times diluted solutions was superior to the others. 2) In color, texture, uniformity, and recuperative strength, the visual quality of turfgrass affected by 500 and 800 times diluted pyroligneous acid were superior to the control continually. It was reliable in the statistics except the recuperative strength. Espe-cially, 500 times diluted solutions tended to be superior to the others. 3) There was no symptom of a disease in all plots. The existing management was thought to be suitable in this golf course. 500 and 800 times diluted pyroligneous acid were not thought to trigger or promote a disease, 4) After investigating the effect of pyroligneous acid on turfgrass growth, the soils of all plots were analyzed. In all plots, the chemical properties of the soils were not changed obviously. 5) Considering the results mentioned above, the practical use of 500 and 800 times diluted solutions might decrease the amount of nutrients and agricultural chemicals used in golf courses as well as promote turfgrass growth in golf courses.

• Journal of Embryo Transfer
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• v.20 no.1
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• pp.43-48
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• 2005

This experiment was carried out to investigate the extender, cooling rate and concentration of glycerol for freezing of boar semen. The result obtained were summarized as follows: 1. Optimal cooling rate was $0.17\~022^{\circ}C/min$ from 25 to $5^{\circ}C$ in LEY extender on the viability and normal acrosome after thawed. 2. The LEY extender was effective in protecting frozen boar semen from cold shock among the extenders(p<0.001, respectively). 3. The sperm viability and normal acrosome rates after thawing was showed greater in the 3 or $4\%$ of glycerol concentration than $2\%$ in LEY extender. 4. Viability of sperm was higher when both 15mM of fructose and 3 or $4\%$ glycerol were added to the LEY extender compared with other concentrations of fructose and glycerol were added it(p<0.001).

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.69-77
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• 1993

Substrate removal efficiency of industrial wastewater from dye plant was investigated with fluidized-bed biofilm reactor(FBBR). Wastewater was diluted by 2, 3 and 6 times for experiment. When F/M ratio was increased 0.2 to 0.3, substrate removal efficiency of wastewater was rapidly decreased in all dilution ratio. Substrate removal efficiency was increased with dilution ratio in same F/M ratio, with hydraulic retention time. In case of 6 times diluted wastewater, below 0.2 F/M ratio, removal efficiency of BOD was $90{\sim}97%$. For reactor design, the parameters such as Y, $k_d$ and r was obtained as follows: $Y=0.3365\;k_d=0.03782\;day^{-1}\;r=0.997$ in 2 times diluted $Y=0.3341\;k_d=0.02750\;day^{-1}\;r=0.996$ in 3 times diluted $Y=0.3365\;k_d=0.03434\;day^{-1}\;r=0.998$ in 6 times diluted

• Journal of the Korean Society of Propulsion Engineers
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• v.14 no.5
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• pp.72-83
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• 2010

Experiments were conducted to investigate the effects of added diluents (carbon dioxide, nitrogen, and helium) on cellular instabilities in outwardly propagating spherical syngas-air premixed flames. Laminar burning velocities and Markstein lengths were measured by analyzing high-speed schlieren images at various diluent concentrations and equivalence ratios. Experimental results showed substantial reduction of the laminar burning velocities and of the Markstein lengths with the diluent additions in the fuel blends. Effective Lewis numbers of helium-diluted syngas-air flames increased but those of carbon dioxide- and nitrogen-diluted syngas-air flames decreased in increase of diluents in the reactant mixtures. With helium diluent, the propensity for cells formation was significantly diminished, whereas the cellular instabilities for carbon dioxide- and nitrogen-diluted syngas-air flames were not suppressed.

• Journal of the Korean Society for Marine Environment & Energy
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• v.2 no.2
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• pp.60-69
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• 1999

In this paper, we have obtained the initial and near-field dilution rates of wastewaters discharged from the ocean outfall of Masan-Changwon municipal wastewater treatment plant from both of field measurements and CORMIX model simulations. In the summer of 1998, water temperature and salinity profiles was measured at 16 stations in the vicinity of the Masan outfall and the dilution rates were analyzed by salinity deficit method. The transport of the wastefields and their initial dilution rates were calculated by CORMIX model using field data as model input. Both of observed and predicted results are shown In very low dilutions with the range of 32～48 from the field data analysis and 29～43 from the model prediction, respectively. This indicates that the water quality in the Masan outfall area can be worsening due to the low dilution rates of diswastewaters, especially, when the ambient currents are very weak in a neap tide and ambient water density is highly stratified in summer.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.11 no.2
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• pp.116-126
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• 1999

In this paper, we have studied the seasonal vanatIons of near-field dilutions of wastewater discharged from the submerged mutiport-diffuser in Masan Bay. Seasonal changes of temperature and salinity, and tidal currents were measured at 16 stations in Masan Bay. Based on the observed ambient field data, the seasonal changes of near-field dilutions due to ambient current and density fields were calculated by CORMIX model. Because of the shallow ambient water depth of 15 m, the density profiles are isopycnal in autumn and winter seasons, in which the dilution factors were the highest, 168 with the strong spring-tidal current and 110-120 with the weak neap-tidal current. As the season changes from spring to summer, the dilution factors are considerably reduced by the factor of 2 as the thermocline is getting deepened up to Sm in depth in summer. In the case of a weak ambient current, the dilution factor in summer was reduced to 1/4 of the dilution in winter. However, with strong ambient current the difference between summer and winter dilutions becomes relatively small by 30%. The results indicate that the seasonal variation of near-field dilution is very large up to 4 times with a weak neap-tidal current, but its variations become small under a strong ambient current of spring tide in MasanBay.

• Journal of the Korean Chemical Society
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• v.28 no.5
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• pp.302-308
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• 1984

X-ray spectrometric determination of $Ta_2O_54, $Nb_2O_5$ and $ZrO_2$ in tin-slag samples using the double dilution technique was conducted. Tin-slag samples and one synthesized standard sample having similar composition to the samples were diluted with anhydrous $Li_2B_4O_7$ at the level of 1.00, 2.00 and 3.00% of the sample content, respectively. The diluted samples were fused at $1,150^{\circ}C$ for 30 minutes, and these glass beads were finely ground and pelletized. With the X-ray intensities measured, analytical results were calculated by the double dilution equation. The results agreed to the reference values obtained by the standard calibration method and the simple dilution technique within allowable error range and were reproducible.

• Journal of Korea Water Resources Association
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• v.32 no.2
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• pp.153-162
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• 1999

In this study, mixing and dilution characteristics of vertical multijet discharged by multiport diffuser into stagnant water are investigated. The results obtained from the experiment of multiport diffuser performed in the three dimensional flume are as follows. As far as merging process of multiport diffuser is concerned, merging starts at about z/l = 3 although merging length is dependent upon stability condition and thereafter lateral temperature distribution becomes gradually uniform which is typical distribution of plane jet. Analyses of experimental data for minimum dilution show that characteristics of minimum dilution are described based on three regions which are jet region where momentum is dominated, intermediate region, and plume region where buoyancy is dominated. Minimum dilution coefficient in plume region of multiport diffuser obtained in this study is 15% higher than that of plane diffuser. This is because individual jet of multiport diffuser entrains more ambient water before merging is occurred, and therefore dilution increases.

• Korean Journal of Plant Resources
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• v.14 no.3
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• pp.206-212
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• 2001

Crude extracts from 20 species of plants 16 families were evaluated for their antifungal activities against Colletotrichum gloeosporioides, and three plant extracts of them were applied to Ginseng in order to investigate the usefulness for Ginseng anthracnose control. Among the crude extracts from 20 species being tested, it of A. cepa, R. undulatum and C. japonica showed considerably antifungal activity against mycelial growth and conidial germination of C. gloeosporioides.. Ginseng anthranose was controlled at 2% concentration of A. cepa and R. undulatum and 1% C. japonica extract, but control value of three plant extracts was inferior to Mancozeb WP. Phytotoxic symptoms were observed in the leaves of ginseng with exogenous foliage application of 10% concentration of three plant extracts and 2% concentration C. japonica extract but not observed at 1% concentration.

• 전기산업
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• v.8 no.2
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• pp.23-41
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• 1997