• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.241-244
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• 2000

Continuous $H_2$ production from CO and water was studied in a trickle bed reactor(TBR) using Rhodopspedomonas palustris P4. To achieve high cell density, R. palustris P4 were cultivated by a fed-batch culture mode under chemoheterotrophic and aerobic condition, and final cell concentration was 13 g/L. TBR could provide sufficient residence time for CO to contact with cell suspension circulating TBR. The maximum CO uptake rate was found to be 16 mmol/L/hr at gas retention time of 50 min and CO partial pressure of 0.4 atm. In our correlation of the experimental data with mathematical model of TBR, the TBR operation with P4 was found to be lie in an intermediate state between mass transfer limitation and kinetic limitation. Due to the high cell density as well as hydrogen production activity in this study, TBR operation showed a superior performance to other previous reports on microbial hydrogen production.

• Journal of the Korean Ceramic Society
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• v.31 no.6
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• pp.637-642
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• 1994

Using SHS(Self-propagating High-temperature Synthesis) method, the optimum synthetic condition of titanium carbonitride was established by controlling the parameters such as relative density of mixture (Ti+C), nitrogen pressure, additive amounts of titanium hydride(TiH1.924) and protecting heat loss. Under 1 atm nitrogen pressure, nitridation ratio with changing relative density of the sample compacts has a maximum (87.2%) at about 55%, and in the case of enveloping the pellet with a quartz tube, the highest nitridation ratio of 90% was obtained at about 68%. At relative density of 55%, nitridation ratio with the nitrogen pressure has a miximum (87.3%) at 7 atm. As the amounts of additive titanium hydride increased, nitridation ratio decreased at below 7 atm nitrogen pressure and, increased at above this pressure until percent of addition percent reached 15 wt% and decreased abruptly upon futher increases in titanium hydride. In the synthesis of TiCxNy by combustion reaction, heat transfer from combustion zone to preheating zone and nitrogen gas penetration into the compact were found to be important factors affecting the TiCxNy formation. It was difficult to obtain high nitridation ratio when the conbustion temperature was either too high or too low, and it seems that the retention of high temperature after a combustion wave sweeped through the reactant mixture pellet is critical to obtain a satisfactory nitridation ratio.

• Food Science and Preservation
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• v.8 no.1
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• pp.23-29
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• 2001

To extend the freshness of late autumn Chinese cabbage, the packaging and loading effects on the quality were investigated during cold storage. Judging from overall quality during storage period, late autumn Chinese cabbage could be stored by 3 months at 0$\^{C}$ cold storage. However, late autumn Chinese cabbage was not acceptable for long-term storage because of its marketability and the storage cost. Among 3 packaging methods(PP-net, carton and plastic container) for stored Chinese cabbage, plastic container and carton were more effective than PP-net packaging for the freshness prolongation. Gas composition in the plastic bags during storage was not significantly different among packaging conditions and O$_2$ and CO$_2$ concentrations were 13∼18% and 0.75∼7.48%, respectively, MAP with plastic film was effective for the quality retention because of low oxygen composition and high humidity condition in the bags.

• Journal of environmental and Sanitary engineering
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• v.21 no.3 s.61
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• pp.15-26
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• 2006

As traffic in city-centre around the world continues to increase, so levels of atmospheric pollutants continue to rise. High concentrations of NOx can have negative effects on human health, and we must find new ways to reduce their levels in the air we breathe. Nitrogen oxide gas (NOx), consisting of nitrogen monoxide (NO) and nitrogen dioxide $(NO_2)$ produced using $O_3$ oxidation, at a low concentration corresponding to that on roads as a result of exhaust from automobiles, was carried out to evaluate the removal characteristics of NOx through a laboratory-scale biofilter packed with soil as a packing material. A mixture media (yellow soil (30%): soil (40%): compost (10%): a used briquet (20%)) was applied. After about 1day of operation, the removal efficiency for $NO_2$ in all experiments with a constant condition ($25^{\circ}C$ and water humidity (60%)) was over 98%. The retention times of the section between phase I and phase II for formation and reduction of $NO_3$ NO and $NO_2$ on the initial $NO_3$ concentration was 50min $(O_3:195\;ppb),\;55min\;(O_3:925\;ppb),\;65min\;(O_3:1743\;ppb),\;70min\;(O_3:2616\;ppb),\;75min\;(O_3:3500\;ppb)$, respectively The soil biofilter system is a unique technology that purifies urban air by utilizing the natural processes that take place in the soil. Although some of the processes are quite complex, they can broadly be summarized as adsorption onto soil particles, dissolution into soil pore water, and biochemical.

• Journal of Korean Society of Water and Wastewater
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• v.14 no.1
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• pp.37-44
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• 2000

Laboratory experiments were conducted to investigate the performances of anaerobic filters packed with ceramic tube and pall-ring media treating a dairy waste. The media packing volume was 65% of effective volume of anaerobic filter. Organics removals of anaerobic filters were maintained above 80% even at an organics loading rate of $10kgCOD/m^3/d$, and this was comparable to aerobic treatment of organic wastes. Organics removals of the ceramic tube anaerobic filters were always lower than those of the pall-ring anaerobic filters due to intrinsic physical property of ceramic tube, especially lower void space which caused to clogging and entrapment of biogas, substrate transfer limitation, and irregular evolution of biogas leading to loss of solids and biomass. This was clearly observed in higher concentration of TSS in the effluent from the ceramic tube anaerobic filter despite of higher retention capacity of TSS compared with pall-ring media. Vertical distribution of organics and solids in the filters showed above 90% of organics and solids in influent were removed below 20% of reactor height, and 50% of remaining organics and solids were removed though media packing zone. Effluent quality from the anaerobic filter was heavily depended on media itself as well as suspended biomass formed below media. It is therefore concluded that the type of media played an important role in biomass accumulation arid gas-liquid-solid separation efficiency. Type of media did not affect the start-up behaviors of the anaerobic filter, and supernatant from anaerobic digested sludge showed a good performance as a seeding materials.

• The Korean Journal of Mycology
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• v.19 no.4
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• pp.292-298
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• 1991

Volatile aroma concentrates of Pleurotus sajor-caju which stored at $20^{\circ}C$ incubator and cold room were obtained by simultaneous distillation-extraction method. The volatile components were identified by combined capillary gas chromatography-mass spectrometry and comparison of retention data on GC of those authentic compounds. Storage at room temperature resulted in significant decreased in their total aroma contents, whereas little changes at cold storage foured, even though appreciable changes were observed in GC pattern between the control and stored samples. Of 38 components identified, ${\delta}-decalactone$ increased while rest of the volatiles decreased rapidly during storage at room temperature, but at cold storage 2-methyl butanal, 1-octen-3-ol, cis,cis-1,5-octadien-3-ol and pentadecanoic acid decreased while 3-octanone, 1-octen-3-one, 3-octanol and 5-undecanol increased with the storage time. The weight losses and organoleptic properties changed extremely by the storage under room temperature, on the other hand, slight changes were found in cold storage.

• The Korean Journal of Mycology
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• v.19 no.4
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• pp.299-305
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• 1991

Volatile aroma concentrates of four oyster mushrooms cultivated in Korea were obtained by the simultaneous distillation-extraction method. The volatile components were identified by the combined capillary gas chromatography-mass spectrometry and compared with the of retention data on GC of those authentic compounds. About 54 volatile compounds were identified in each of the four edible oyster mushrooms. The main compounds in Pleurotus ostreatus ASI 201 were 1-octen-3-ol, 3-octanone, 3-octanol, in Pleurotus sajor-caju, 1-octen-3-ol, 3-octanone, 1,5-octadien-3-one, 3-octanol, in Pleurotus florida-ostreatus-ostreatus, 1-octen-3-ol, n-hexanol, 3-octanone, 3-octanol, phenol, and in Pleurotus ostreatus (Ae-Neutari), 1-octen-3-ol, n-pentanal, n-hexanol, n-pentanol, 3-octanone, 3-octanol, 1,5-octadien-3-one, respectively. The mushrooms worked were rich in an alcohols and carbonyl compounds containing $C_8$ compounds. The peak area ratio of $C_8$ compounds in aroma concentrates were 56.60% in Pleurotus ostreatus ASI 201, 72.46% in Pleurotus sajor-caju, 54.84% in Pleurotus florida-ostreatus-ostreatus and 35.85% in Pleurotus ostreatus (Ae-Neutari ), respectively.

• Fisheries and Aquatic Sciences
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• v.6 no.3
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• pp.155-159
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• 2003

Lipid composition and fatty acid composition were characterized in the membrane of a marine ciliate protozoan (Uronema marinum). Phospholipids accounted for 70% of total lipid, and the remainder was neutral lipids. Total phospholipids were separated as phosphatidylcholine $(24.26\%)$, phosphatidylethanolamine $(22.21\%)$, phosphatidylinositol $(6.14\%)$, phosphatidyl­serne $(5.11\%)$, cardiolipin $(3.07\%)$ and unidentified phospholipids $(28.72\%)$ through high performance liquid chromatography (HPLC). Fatty acid composition of neutral lipids and phospholipids was determined by gas chromatography (GC), based solely on comparision of retention times. In neutral lipids, the most abundant fatty acid group was monounsaturated fatty acid $(48.3\% of total fatty acids)$ with oleic acid (18:1) and nervonic acid (24:1). Saturated fatty acids comprised $29.6\%$ of total fatty acids, with palmitic acid (16:0), stearic acid (18:0) ane myristic acid (14:0), and polyunsaturated fatty acid accounted for $33.0\%$ with $Di-homo-\gamma-linolenic$ acid (20:3) and linoleic acid (18:2). Wherease phospholipids predominantly contained the fatty acid group in the following order: polyunsaturated fatty acids $(52.7\%\;of\;total\;fatty\;acids)$ with linoleic acid (18:2) and $\gamma-linolenic$ acid (18:3) > monounsaturated fatty acids $(28.5\%\;of\;total\;fatty\;acids)$ with oleic acid (18:1) and palmitoleic acid (16:1) > saturated fatty acids $(25.5\%\;of\;total\;fatty\;acids)$ with palmitic acid (16:0), stearic acid (18:0) and myristic acid (14:0).

• Applied Biological Chemistry
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• v.40 no.2
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• pp.144-147
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• 1997

Different isolation methods for the volatile components of Anise(Pimpinella anisum L.) are compared in terms of the difference of components obtained with each analytical procedure. These methods include headspace(purge & trap) sampling procedure, simultaneous distillation extraction(SDE), steam distillation and solvent extraction. Total 43 components were identified by? comparing gas chromatography retention time and mass spectral data. Different isolation techniques result in compositionally different isolates. The headspace(purge & trap) sampling procedure was found to be the best method of choice for a qualitative analysis of the volatile components.

• Journal of Wetlands Research
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• v.13 no.2
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• pp.199-208
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• 2011

Scarcity of water worldwide, increasing greenhouse gas emissions, increased energy consumption due to the Earth is threatened. Existing in the process of urban planning and development of forests, rivers and other natural ecosystems have been destroyed and that there was increased impervious pavement. Impervious pavement increase water circulation system to destroy the natural and urban water retention, infiltration and decreased evaporation. Nonpoint source pollution(NPS) occurs when rainfall impervious pavement and appeal directly to the river water inflow is adversely impacts of the situation. In this study, rainfall occurs impervious pavement NPS pollution reduction and temperature increase due to the increase in urban areas, and to solve heat island phenomenon is to develop small HSSF constructed wetland technology. The small HSSF constructed wetland sedimentation, filtration, adsorption, absorption by vegetation, including such mechanisms. Techniques for verification of the pilot-scale test was conducted. In the future domestic urban heat island phenomenon and restore the natural water cycle for the facilities will be used as a basis to develop.