• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.441-442
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• 2000

This study was conducted to extend the storage period of onion. After pre-drying process of onion, its storage was investigated at room temperature during a month. When ozone was treated with the concentration of 3 ppm in warehouse, the weight loss and the rotten rate of onion were remarkably decreased compared with control. Typical odor of onion was completely removed by the ozone treation during the storage.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.532-539
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• 2011

The physical and chemical properties of the dried low rank coals (LRCs) before and after the surface treatment using ozone and ammonia were characterized in this study. The contents of moisture, volatiles, fixed carbon and ash consisting of dried LRCs before the surface treatment were about 2.0, 44.8, 44.9 and 8.9%, respectively. Also, it was composed of carbon of 62.66%, hydrogen of 4.33%, nitrogen of 0.94%, oxygen of 27.01% and sulfur of 0.09%. The dried LRCs was surface-treated with the various dry methods using gases such as ozone at room temperature, ammonia at $200^{\circ}C$ and then the dried LRCs before and after the surface treatment were characterized by the various analysis methods such as FT-IR, TGA, proximate and elemental analysis, caloric value, ignition test, adsorption of $H_2O$ and $NH_3-TPD$. As a result, the oxygen content increased and the calorific value, ignition temperature and the contents of carbon and hydrogen relatively decreased because the oxygen-contained functional groups were additionally generated by the surface oxidation with ozone which plays a role as an oxidant. Also, its $H_2O$ adsorption ability got higher because the hydrophilic oxygen-contained functional groups were additionally generated by the surface oxidation with ozone. On the other hand, it was confirmed that the dried LRCs after the surface treatment with $NH_3$ at $200^{\circ}C$ have the decreased oxygen content, but the increased calorific value, ignition temperature and contents of carbon and hydrogen because of the decomposition of oxygen-contained functional groups the on the surface. In addition, the $H_2O$ adsorption ability was lowered bucause the surface of the dried LRCs might be hydrophobicized by the loss of the hydrophilic oxygen-contained functional groups. It was concluded that the various physico-chemical properties of the dried LRCs can be changed by the surface treatment.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2002.05a
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• pp.267-272
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• 2002

The electric heat pump requiring HCFCs as a refrigerant has been for most residential air-conditioners in Korea. They cause a surge up electric power demand during summer. Moreover, the use of HCFCs and HFCs causes a serious problem to the global environment such as global warming and ozone layer destruction. An absorption chiller and heater could solve such problems. It was built and tested for analyzing the performance of the absorption chiller/heater. Experiment was done with a 1.5RT household absorption chiller and heater. It was experimented that the cooling capacity, gas capacity, COP were researched by the temperature of cooling water. The change of the cooling water temperature have effect the temperature(or pressure) of the parts on absorption chiller The result of the change of the cooling water temperature have the effects of the absorption chillers. This data will help to operate the household absorption chiller and heater.

• Proceedings of the KSME Conference
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• 2004.04a
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• pp.1334-1339
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• 2004

Nowadays CFCs and HCFCs refrigerants are restricted because it cause depletion of ozone layer. Accordingly, this experiment apply the $NH_3$ gas and not CFCs and HCFCs for refrigerant to study the performance characteristic from the superheat control and improve the energy efficiency from the high performance. The condensing pressure of refrigeration system is increased from 14.5bar to 16bar by 0.5bar and superheat temperature is increased from $0^{\circ}C$ to $10^{\circ}C$ by $1^{\circ}C$ at each condensing pressure. As the result of experiment, when the superheat temperature is $1^{\circ}C$ at each condensing pressure, the refrigeration system has the high performance.

• Journal of Environmental Science International
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• v.16 no.12
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• pp.1463-1468
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• 2007

Emission of methyl bromide(MeBr) of soil fumigant was implicated in stratospheric ozone depletion. To determine the environmental fate for 1,3-dichloropene(1,3-D) of alternatives fumigants for MeBr, this paper researched the transformation for 1,3-D in water and soil. Half lives of cis-1,3-D in water with first-order kinetics are 9.9day and 1.7day at $25^{\circ}C\;and\;40^{\circ}C$, half lives of trans-1,3-D are 8.6day and 1.5day at $25^{\circ}C\;and\;40^{\circ}C$, respectively. Transformation for 1,3-D in water at high temperature faster then at low temperature. Hydrolysis for 1,3-D in water are unaffected at $pH\;2.5{\sim}pH\;10.0$, but hydrolysis for 1,3-D at pH 11.5 higher then at $pH\;2.5{\sim}pH\;10.0$. Half lives of cis-1,3-D in soil are 11.5day and 7.7day at 3% and 10% of soil moisture, half lives of trans-1,3-D are 9.9day and 6.9day at 3% and 10% of soil moisture, respectively. Transformation for 1,3-D in water increased with increasing soil moisture. Transformation for trans-1,3-D isomer are more rapid then cis-1,3-D isomer in water and soil. This research has identified that transformation for 1,3-dichloropropene are affected by temperature, pH, soil moisture, and isomer of cis and trans in water and soil.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2003.05d
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• pp.61-64
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• 2003

This paper presents Bi thin films have been fabricated by atomic layer-by-layer deposition and co-deposition at an IBS method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. Mg(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 655 and $820^{\circ}C$ and the highly condensed ozone gas pressure$(PO_3)$ in vacuum chamber was varied between $2.0{\times}10^{-6}$ and $2.3{\times}10^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $O_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with $T_c$(onset) of about 90 K and $T_c$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as $CaCuO_2$ was observed in all of the obtained films.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.615-618
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• 2003

This paper presents Bi thin films have been fabricated by atomic layer-by-layer deposition and co-deposition at an IBS method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(l00) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was varied between 655 and 820 $^{\circ}C$ and the highly condensed ozone gas pressure(PO$_3$) in vacuum chamber was varied between 2.0$\times$10$^{-6}$ and 2.3$\times$10$^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and 795$^{\circ}C$ and single phase of Bi 2201 existed in the lower region than 785 $^{\circ}C$. Whereas, PO$_3$ dependance on structural formation was scarcely observed regardless of the pressure variation. And high quality of c-axis oriented Bi 2212 thin film with T$_{c}$(onset) of about 90 K and T$_{c}$(zero) of about 45 K is obtained. Only a small amount of CuO in some films was observed as impurity, and no impurity phase such as CaCuO$_2$ was observed in all of the obtained films.lms.

• Korean Chemical Engineering Research
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• v.48 no.4
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• pp.540-543
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• 2010

In this study, we made low temperature plasma reactor in order to treat safely $NO_x$ which included in the gas. We investigated experimently and inspected efficiency characteristics of equipment about flow rate of reactant material and discharge input power which supplied into reactor. As a reaction gas, by using mixture gas of $NO/N_2$ and $N_2/O_2$, we setted up initial NO concentration and supplied the speed of a current to 1~4 l/min. When the amount of flow increased, reduction rate of NO was low. Also when discharge input power was high, decomposition of NO was easy. Also the longer delay time of reaction material and the higher discharge input power was, the higher decomposition energy efficiency was. And when the amount of flow was much, and the more discharge input power increased, the more ozone generated.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.486-487
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• 2007

$Bi_2Sr_2Ca_{n-1}Cu_nO_x$(n=0, 1, 2) thin films have been fabricated by co-deposition at an ultra-low growth rate using ion beam sputtering(IBS) method. The growth rates of the films was set in the region from 0.17 to 0.27 nm/min. MgO(100) was used as a substrate. In order to appreciate stable existing region of Bi 2212 phase with temperature and ozone pressure, the substrate temperature was between 655 and $820^{\circ}C$ and the highly condensed ozone gas pressure in vacuum chamber was varied between $2{\times}10^{-6}{\sim}4{\times}10^{-5}$ Torr. Bi 2212 phase appeared in the temperature range of 750 and $795^{\circ}C$ and single phase of Bi 2201 existed in the lower region than $785^{\circ}C$. Whereas, $PO_3$ dependance on structural formation was scarcely observed regardless of the pressure variation.

• Journal of Life Science
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• v.16 no.3 s.76
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• pp.534-539
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• 2006

In the ozone disinfection unit process of a piston type batch reactor with continuous ozone analysis using a flow injection analysis (FIA) system, the CT values for 1 log inactivation of Cryptosporidium parvum by viability assays of DAPI/PI and excystation were $1.8{\sim}2.2\;mg/L{\cdot}min$ at $25^{\circ}C$ and $9.1mg/L{\cdot}min$ at $5^{\circ}C$, respectively. At the low temperature, ozone requirement rises $4{\sim}5$ times higher in order to achieve the same level of disinfection at room temperature. In a 40 L scale pilot plant with continuous flow and constant 5 minutes retention time, disinfection effects were evaluated using excystation, DAPI/PI, and cell infection method at the same time. About 0.2 log inactivation of Cryptosporidium by DAPI/PI and excystation assay, and 1.2 log inactivation by cell infectivity assay were estimated, respectively, at the CT value of about $8mg/L{\cdot}min$. The difference between DAPI/PI and excystation assay was not significant in evaluating CT values of Cryptosporidium by ozone in both experiment of the piston and the pilot reactors. However, there was significant difference between viability assay based on the intact cell wall structure and function and infectivity assay based on the developing oocysts to sporozoites and merozoites in the pilot study. The stage of development should be more sensitive to ozone oxidation than cell wall intactness of oocysts. The difference of CT values estimated by viability assay between two studies may partly come from underestimation of the residual ozone concentration due to the manual monitoring in the pilot study, or the difference of the reactor scale (50 mL vs 40 L) and types (batch vs continuous). Adequate If value to disinfect 1 and 2 log scale of Cryptosporidium in UV irradiation process was 25 $mWs/cm^2$ and 50 $mWs/cm^2$, respectively, at $25^{\circ}C$ by DAPI/PI. At $5^{\circ}C$, 40 $mWs/cm^2$ was required for disinfecting 1 log Cryptosporidium, and 80 $mWs/cm^2$ for disinfecting 2 log Cryptosporidium. It was thought that about 60% increase of If value requirement to compensate for the $20^{\circ}C$ decrease in temperature was due to the low voltage low output lamp letting weaker UV rays occur at lower temperatures.