• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.2
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• pp.146-153
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• 2004

A Promising new approach to achieve low pollutant emissions and improvement of flame stability is tested experimentally using a cyclone jet hybrid combustor employing both premixed and diffusion combustion mode. Three kinds of nozzle are tested for mixing enhancement of fuel and air. The LNG (Liquified Natural Gas) is used as a fuel. The combustor is operated by two methods. One is DC (Diffusion Combustion) mode generated swirl flow by air as general swirl combustor, and the other is HC (Hybrid Combustion) mode. The HC mode consists of diffusion jet flame of axial direction and premixed cyclone flame of tangential direction in order to stabilized the diffusion jet flame. The results showed that the flame stability of HC mode is significantly enhanced than that of DC mode through the change of mixing characteristics by modifications of fuel nozzle. In addition, the reductions of CO and NOx emission in HC mode, as compared with that for the DC mode, is large than about 50% in stable region. Also, even using the low calorific fuel as $CO_2$-blended gas, it is identified that the cyclone jet hybrid combustor has the high performance of flame stability.

• Journal of the Korean Society of Groundwater Environment
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• v.4 no.4
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• pp.199-211
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• 1997

As a part of study on geological disposal of radioactive waste, hydrogeochemical characteristics of deep granitic groundwater in Korea were investigated through the construction of a large geochemical dataset of natural water, the examination on the behaviour of dissolved constituents, and the consideration of phase stability based on thermodynamic approach. In granitic region, the contents of total dissolved solids increase progressively from surface waters to deep groundwaters, which indicates the presence of more concentrated waters at depth due to water-rock interaction. The chemical composition of groundwater evolves from initial $Ca^{2＋}$－(C $l^{－}$＋S $O_4$$^{2-}$) or $Ca^{2＋}$-HC $O_3$$^{－}$ type to final N $a^{＋}$-HC $O_3$$^{－}$ or N $a^{＋}$－(C $l^{－}$＋S $O_4$$^{2-}$) type, via $Ca^{2＋}$-HC $O_3$$^{－}$ type. Three main mechanisms seem to control the chemical composition of groundwater in the granitic region; 1) congruent dissolution of calcite at shallower depth, 2) calcite precipitation and incongruent dissolution of plagioclase at deeper depth, and 3) kaolinite-smectite or/and kaolinite-illite reaction at equilibrium at deeper depth. The behaviour of dissolved major cations (C $a^{2＋}$, $K^{＋}$, $Mg^{2＋}$, M $a^{＋}$) and silica is likely to be controlled by these reactions.

• 한국연소학회:학술대회논문집
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• 2004.06a
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• pp.173-179
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• 2004

Combustion of refuse derived fuel(RDF) and refuse plastic fuel (RPF) was carried out in a lab-scale circulating fluidized bed. Experiment was investigated cold flow visualization. RDF was made by C & tech and RPF was made by KRS. The results include distribution of temperature in the combustion chamber, and concentrations of flue gas such as $O_2$, $CO_2$, CO, $NO_x$ and HCs Micro G.C(gas chromatograph) was employed to find out concentration of He Temperature distribution was different when RDF and RPF were burnt respectably. As air ratio became increased, $CO_2$, CO, and total of HCs emissions were decreased. According to the number of carbon atom of HCs, HC were classified as five kinds of HC.

• The Journal of the Korean dental association
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• v.11 no.1
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• pp.45-52
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• 1973

Ketamine HC1(Phencyclidine derivative) is a white, crystalline substance with melting point 259℃. It is soluble in water to a 20% clear, colorless solution. a 10% aqueous solution has a pH 3.5. The chemical structure is 2-(O-chlorophenyl)-2-(methylamino) cyclohexanone hydrochloride. It is a rapid acting, nonhypnotic, nonbarbiturate drug with a wide safety margin. The author used the anesthetic ketamine hydrochloride for oral surgery procedure in 16 patients(2 to 33 years). Anesthesia was achieved with a single intramuscular injection by introduction of manufacture. Result obtained as follows : 1. It was easily administered. 2. Onset time was rapid and duration was short. 3. The mild cardiac stimulation resulted in moderate increase in the blood pressure and pulse. 4. There was no significant respiratory depression. 5. The airway can be maintained without artificial support or endotracheal intubation. 6. All protective reflex maintained, which was important in oral surgery. 7. The best results were achieved in pediatric patients than adults.

• Korean Journal of Veterinary Research
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• v.50 no.3
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• pp.179-185
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• 2010

The present study was undertaken to establish reference values for the composition blood lymphocyte populations and compare forty three Hanwoo neonatal calves (KC) with twenty one Holstein calves (HC) by blood cell count and immunophynotying. The percentages of CD2+, CD4+, CD8+, CD26+, ACT2+, MHC class, MHC class II and WC1+ T cells, B cells were determined by flow cytometry. The number of lymphocyte and monocyte in HC were higher than those of KC. However, the number of neutrophils was higher in HC than KC. The proportions of CD2+, CD4+, CD8+, MHC class, and WC1+ lymphocytes remained relatively stable during the study period, while there was a moderate increase in the relative percentage of CD26+, ACT2+, MHC class II and B cell from birth to approximately 3 weeks of age. Marked differences in the relative proportions of the lymphocyte subpopulations were noted between the individual calves. The present study shows that the T-cell subpopulations are present in peripheral blood of KC at levels comparable with HC, while the MHC class II and B cell population of KC increases significantly with age. The absolute number of WBC in KC was due to the decrease of absolute number of neutrophil rather than the increase of lymphocyte. The results indicated that KC have significantly higher number of neutrophils, and proportion of MHC class II and B cell than HC.

• Journal of The Korean Society of Grassland and Forage Science
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• v.18 no.2
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• pp.79-88
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• 1998

This experiment was conducted from May to August in 1997 to selected the wrn hybrids being suitable for silage at farm in the Kongju National University through the comparison of growth characteristics, forage yield and growth analysis about native and imported corn hybrids for silage production. In this experiment, trial design was a randomized block design with three replication, testing varieties were 4 hybrids (Suwon 19, Kwanganok, Whengsungok, Suwonok ) of native corn hybrids and 13 hybrids (P 3156, P 3352, P 3144w, DK 501, DK 689, DK 713, DK 729, H 643.99, H 545.64, H 645.12, HC 7466, H 644.18, H ALISEO) of imported corn hybrids. The results obtained are summarized as follows; 1. The emergence rate of H643.99 was the highest with 97.0%. In rice black streaked dwarf virus(RBSOV), the hybrid of HC 7466 was lower infected with 1.6% than other hybrids. The plant hight of P 3144w was the highest with 339 cm and the stem length of P 3156 was the highest with 261 cm. In native com hybrids, the plant height and stem length of Kwanganok were recorded with 306 cm and 235 cm, respectively. 2. Leaf number and leaf area of Kwanganok were the greatest with 16 sheet per plant and $5,180\;{\textrm{m}^2}/l0a$, respectively. H 645.12 and H 545.64 had the greatest in ear to total dry matter ratio with 49.5% and 49.4%, respectively. 3. The fresh matter yield was significantly difference between growth stage, So Suwon 19 had the most level at 15 days before silking, P 3352 had the most level at silking date, Kwananok had the most level at 35 days a after silking. The fresh matter yield of native com hybrids such as Suwon 19 and Kwanganok was not apparent diffreences as compared with imported corn hybrids. 4. As the results of survey with dry weight, the quantity of dry matter accumulation were increase after silking. The varieties of P 3352, P 3156, Kwanganok, OK 713 were more quantity of dry matter production than DK 501, HC 7466. The Kwanganok of native com hybrid and Pioneer strain with high percentage of dry matter were higher dry weight than Limagrain strain. 5. HC 7466 had the largest LAR with $6.53\;{\textrm{cm}^2}/g$, H545.12 had the lowest LAR with $3.30\;{\textrm{cm}^2/g}$. P 3144 had the largest LAI, DeKalb strain including DK 713 were larger apparently than Limagrain strain including HC 7466 with 3.15. 6. The RGR of testing varieties was little difference of statistical significantly, but DK 501, and HC 7466 were lower than other corn hybrids. The CGR of native and American varieties was no apparent differences, but that of Limagrain strains were a large variation. According to the results obtained by this experiment, the eary growth such as emergence rate and RBSDV infection rate of Limagrain strains was more excellent than other strains. P 3156, P 3352, P 3144w, DK 713 and HC 7466 were suitable for silage condition such as dry matter yield, percentage of dry matter and % ear to total dry matter. The fresh and dry matter yield of native corn hybrids such as Suwon 19 and Kwanganok were not apparent differences as compared with imported corn hybrids, but percentage of dry matter was lower than other imported corn hybrids.

• Journal of Energy Engineering
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• v.24 no.4
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• pp.140-145
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• 2015

This study was aimed at analyzing NOx conversion characteristics in the HC-SCR with biodiesel content changes of the secondary fuel injection (BD0, BD10, BD25). Test conditions for temperature were set to $290^{\circ}C$, $320^{\circ}C$ and $350^{\circ}C$ considering the upstream temperature of a HC-SCR, distillation of the secondary injected fuels and etc. The amount of fuel injection was adjusted with a fixed space velocity of 55,000(1/h). According to the test results of distillation, the T90 was the same level about $350^{\circ}C$ on all test fuels and the amount of evaporation was reduced at lower than $350^{\circ}C$ temperature condition with increasing biodiesel content. As biodiesel content which is mixed with the secondary injected fuel is increased, NOx reduction efficiency was determined to decrease. The difference of the Nox reduction ratio in a high temperature condition($320^{\circ}C$ and $350^{\circ}C$) than the low temperature($290^{\circ}C$) was more significant. These results are thought to be poor evaporation properties (distillation) and high molecular weight of the biodiesel.

• Journal of Korean Society for Atmospheric Environment
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• v.3 no.1
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• pp.55-64
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• 1987

Actual driving pattern of each motor vehicle type was measured and analyzed in Seoul area and vehicle emission rate was measured and traffic data were used to estimate vehicular emission factor and motor vehicle-related air pollutant emission. The analysis of contribution ratio of each vehicle type showed that LPG taxi's took 38.1% of total vehicular CO, gasoline passenger cars 37.5%, therefore, these cars are major sources of CO, gasoline passenger cars took 45.4% of total vehicular HC, motorcycles 25.3%, LPG taxi's 16.2%, so motorcycles can be said to play an important role in HC emission. For NOx, buses and trucks were thought to be major sources as buses took 36.8% and truck 26.4%. Diesel vehicles, on the other hand, took most $SO_2$ and particulate matter emission. Total emission from motor vehicles in Seoul was estimated to be 547 t/day of CO, 68t/day of HC, 163t/day of NOx, 18t/day of $SO_2$ and 19t/day of paticulate matter.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.631-636
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• 1991

The bacteria which can biodegrade aromatic compounds were screened from soil and wastewater. The isolated Pseudomonas sp. HC107 had high removal rate of COD and phenol. And also this strain grew on m-cresol, salicylate, toluene, 2, 4-D and benzene. When the strain culture (2 ml/day) was treated on continuous reactor at mixed wastewater from chemical, pharmaceutical and dye industry, the treatment rate of COD, BOD and phenol was to be about 92.5%, 95.3% and 93.5%, respectively.

• Journal of the Korean Society of Groundwater Environment
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• v.3 no.1
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• pp.37-49
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• 1996

The objectives of this study are to investigate the groundwater and surface water contamination, to interpret the attenuation mechanism of contaminant transport, and to find the appropriate contamination indicator. at the two big landfill sites : Nanjido Landfill and Hwasung Landfill. Leachate from the Nanjido, th, Hwasung and the Kimpo waste disposal sites is characterized by high temperature (31.7-40.1$^{\circ}C$), high electric conductivity (14,650-32,800 ${\mu}$S/cm), somewhat higher pH(7.58-8.45) and low Eh (-119.4-20.4 mV), and is enriched in both major (Na$^{＋}$, K$^{＋}$, Ca$^{2＋}$, Mg$^{2＋}$, HC $O_3$$^{－}$, Cl$^{－}$) and minor (Mn, Sr$^{2＋}$, Ba$^{2＋}$, Li$^{＋}$, F$^{－}$, Br$^{－}$) ions. Municipal solid waste leachate and industrial waste leachate are effectively discriminated by the content of S $O_4$$^{2－}$, Fe, and heavy metals. The attenuation mechanism of each component was assessed using the chemical analysis. Cl-normalizing process, WATEQ4F simulation, and preceding flownet analysis. Based on the calculation of Contamination Factor, K, Na, Ca, Mg, B, Zn, HC $O_3$, Cl, F, Br and TOC are effective contamination indicators in the Nanjido landfill site, and K, Na, Ca, Mg, B, S $O_4$, HC $O_3$, Cl, F, Br and TOC in the Habsburg landfill site Particularly, TOC is the best contamination indicator in landfill sites influenced by sea water.