• Journal of Korean Society on Water Environment
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• v.27 no.4
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• pp.461-466
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• 2011

The feasibility of utilizing food waste leachate as an external carbon source was tested to enhance biological nutrient removal from an industrial wastewater with an average flow rate of $164,800m^3/d$ and a low carbon/nitrogen ratio of 2.8. A considerable improvement in the removal of nitrogen and phosphorus was observed when a certain amount of the leachate, ranging from 70 to $142m^3/d$, was supplemented to the biological industrial wastewater treatment process. The addition of the leachate led to an increase in the BOD/N ratio (4.5) and the removal efficiency of nutritents from 29.7% to 71.7% for nitrogen and from 34.8% to 65.6% for phosphorus. However, an excessive dose of the leachate that significantly exceeded $120m^3/d$ caused serious operational problems, like oil-layer formation in the grit chamber and scum layer in the primary clarifier. Thus, an supplement of food waste leachate at a dose acceptable to an existing facilities can be a practical and effective means to enhance the nutrient removal from industrial wastewater and to dispose of the food waste leachate.

• Food Engineering Progress
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• v.13 no.1
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• pp.24-31
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• 2009

The structural and physicochemical properties of dried aloe vera gel by DIS (dewatering impregnation soaking) process under optimum conditions were investigated. FT-IR spectra for dried samples of DIS aloes showed the typical patterns of standard aloe polysaccharide, and surface structures by SEM (scanning electron microscopy) were similar to a gel-like structure. In case of physicochemical properties of dried aloe samples by DIS process, solubilities and swelling powers of control (not osmotic treated aloe), DIS (S) and DIS (G), samples treated by osmotic solution of 60% sucrose/0.25% NaCl and 50% glucose/0.5% NaCl, were 48.3-57.3% and 8.3-11.7%, respectively, showing no significant differences among samples, but swelling power of DIS (PEG), sample treated by using 50% polyethylene glycol as an osmotic agent was about 5 times higher that of control. Also, water holding capacities of control, DIS (S) and DIS (G) were similar to each other, but that of DIS (PEG) was about 5 times higher that of control. Oil holding capacities of control and DIS aloes maintained the 50.9-86.4% levels of water holding capacities showing no significant differences among samples. Rehydration ratio of DIS (PEG) aloes were significantly dependent on the temperature of rehydrated solvent (water), and rehydration ratio of not-fileted aloe was about two folds higher than that of fileted aloe.

• Journal of Microbiology and Biotechnology
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• v.11 no.3
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• pp.369-375
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• 2001

Urushiol, a natural monomeric oil, was used to prepare a detergentless micro-emulsion with water and 2-propanol The formation of micro-emulsion was verified by conductivity measurements and dynamic light scattering. The conductivity data showed phase change dynamics, a characteristics of micro-emulsions, and subsequent dynamic light scattering study further confirmed the phenomenon. Average water droplet diameter was 10 nm to 500 nm when the molar ratio of 2-propanol ranged from 0.40 to 0.44 . Earlier studies were performed on toluene and hexane, in which the insoluble substrate in water phase was added to the solvents to be reacted on by enzymes. However, in the present urushiol system, urushiol was used as both solvent and substrate in the laccase polymerization of urushiol. The laccase activity in the system was examined using polymerization of urushiol. The laccase activity in the system was examined using syringaldezine as a substrate, and the activity increased rapidly near the molar ratio of 2-propanol at 0.4, where micro-emulsion started. The activity rose until 0.46 and fell dramatically thereafter. The study of laccase activity in differing mole fractions of 2-propanol showed the existence of an ‘optimal zone’, where the activity of laccase was significantly higher. In order to analyze urushiol polymerization by laccase, a bubble column reactor using a detergentless micro-emulsion system was constructed. Comparative study using other organic solvents systems were conducted and the 2-propanol system was shown to yield the highest polymerization level. The study of laccase activity at a differing mole fraction of 2-propanol showed the existence of an ‘optimal zone’ where the activity was significantly higher. Also, 3,000 cP viscosity was achieved in actual urushi processing, using only 1/100 level of laccase present in urushi.

• Korean Journal of Food Science and Technology
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• v.17 no.2
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• pp.95-100
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• 1985

Effects of number of washings with solvents on drying rates and physicochemical properties of dried soymilk residues(SMR) were investigated. The dried soymilk residue was prepared by washing the residue with acetone or ethanol, followed by drying at $60^{\circ}C$. Increase of number of washings with a residue/solvent ratio of 1/1.5 resulted in an increase in drying rate and in protein content of the residue while the lipid content decreased. The brightness of the dried residue and the properties of water and oil absorption were also improved by washing with acetone which was advantageous to ethanol for all of the properties measured. Washings more than 3 times with acetone or 2 times with ethanol were found to be less effective in terms of quality improvement. The more addition of dried residue into the mixture of SMR-wheat flour resulted in a linear increase of water and oil absorption characteristics.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.1
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• pp.21-29
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• 2013

Present study was conducted to evaluate the performance of Anaerobic Hybrid Reactor (AHR) combined with two types of anaerobic attached growth reactors at mesophilic temperature ($37^{\circ}C$). The reactor was operated at the influent substrate condition of 19,400 mg/L soluble chemical oxygen demand (sCOD). The organic loading rate (OLR) and flow rate were varied in the range of $9.5{\sim}22.5kg/m^3$. day and 10.6 ~ 26.0 L/day respectively since start-up was done. The COD removal efficiency of 93 % was measured at the OLR of $14kg/m^3$. day in AHR. However a reduction in removal efficiency to as low as 85 % could have been related to a combined effect of high concentration suspended solids (SS) concentration over 3,800 mg/L. On the other hand the total COD removal efficiencies were measured to be 96.3 % and 96.2 % for AHR+APF and AHR+ADF respectively. The pH of the POME was adjusted to neutral range by using sodium bicarbonate at the initial stages of the reactor feed, later stages pH adjustment was not required as the pH was maintained in the desired neutral range due to self-buffering capacity of the reactor. The reactor proved to be economically acceptable and operationally stable. The biogas was measured to have $CH_4$ and $CO_2$ with a ratio of 35:65, and methane gas production rate was estimated to be $0.17{\sim}10.269L\;CH_4/g\;COD_{removed}$.

• Korean Journal of Food Science and Technology
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• v.19 no.5
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• pp.430-434
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• 1987

Fatty acid fraction rich in ${\omega}-3$ polyunsaturated fatty acids (${\omega}-3$, PUFA), especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) could be obtained by saponification of fish oil in ethanol containing alkali hydroxide followed by cooling and filtration of the resultant solution. Fatty acid compositions of fish oil and the concentrates suggest that the ratio of number of double bonds to carbon number in a fatty acid molecule is a more important factor than the degree of unsaturation or the chain length in determining the solubility of fatty acid salts in ethanol. Water content in ethano1 affected significantly the efficiency of the separation with respect to yield and content of EPA and DHA in the concentrates; the lower the water content, the higher the efficiency. It was, however, influenced little by cooling procedure and temperature which the saponified solution experienced during the crystallization. Under an optimal condition, the contents of EPA and DHA in the concentrate increased by 2.4 and 2.5 times, respectively, as compared with those in sardine oil.

• Archives of Pharmacal Research
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• v.28 no.9
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• pp.1097-1102
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• 2005

An O/W microemulsion system was developed to enhance the skin permeability of ace-clofenac. Of the oils studied, Labrafil? M 1944 CS was chosen as the oil phase: of the microemulson, as it showed a good solubilizing capacity. Pseudo-ternary phase diagrams were constructed to obtain the concentration range of oil, surfactant, Cremophor ELP, and co-surfactant, ethanol, for micoemulsion formation. Eight different formulations with various values of oil of $6-30\%$, water of $0-80\%$, and the mixture of surfactant and co-surfactant (at the ratio of 2) of $14-70\%$. The in vitro transdermal permeability of aceclofenac from the microemulsions was evaluated using Franz diffusion cells mounted with rat skin. The level of aceclofenac permeated was analyzed by HPLC and the droplet size' of the microemulsions was characterized using a Zetasizer Nano-ZS. Terpenes were added to the microemulsions at a level of $5\%$, and their effects on the skin permeation of aceclofenac were investigated. The mean diameters of the microemulsions ranged between approximately $10\~100nm$, and the skin permeability of the aceclofenac incorporated into the microemulsion systems was 5-fold higher than that of the ethanol vehicle. Of the various terpenes added, limonene had the best enhancing ability. These results indicate that the microemulsion pystem studied is a promising tool for the percutaneous delivery of aceclofenac.

• Journal of Soil and Groundwater Environment
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• v.24 no.1
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• pp.17-23
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• 2019

Clean soil environment is of crucial importance to sustain lives of ecosystem and humans. With rapid industrialization, there has been a great increase of soil contamination by accidental releases of petroleum products. In general, soil remediation is an expensive and time-consuming process as compared to cleanup of water and air. Moreover, determining the source and responsible parties of soil pollution often turns into legal conflicts and that further delay the cleanup process of contaminated sites. In practice, total petroleum hydrocarbon (TPH) analysis has been employed to determine the petroleum species and to track down the responsible polluters. However, this approach often suffers from differentiating similar TPH species. In this study, we analyzed TPH chromatogram patterns of 24 domestic petroleum products in specific carbon ranges (${\sim}C_{10}$, $C_{10}-C_{12}$, $C_{12}-C_{36}$, and $C_{36}{\sim}$) and the fractional changes of THP ratio in the mixture products of gasoline, kerosene and diesel. The proposed TPH analysis method in this study could serve as a useful tool to better analyze the petroleum species in soils contaminated with complex oil mixtures, and ultimately be used to identify the polluters of soil.

• Korean Journal of Food Science and Technology
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• v.24 no.2
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• pp.111-116
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• 1992

Production of cocoa butter equivalent fat (CBE) from palm oil and stearic acid by reverse micelle lipase reaction system was studied. Qualitative and quantitative analyses of triglycerides were performed by HPLC. The reaction conditions for maximum conversion from triolein and stearic acid to 1-stearoyl-2,3-dioleoyl glycerol(SOO) and 1,3-distearoyl-2-oleoyl glycerol(SOS) were as follows: a molar ratio of water/Aerosol OT, 10; triolein, 30 mM; stearic acid, 90 mM; pH, 7.5; and temperature, $50^{\circ}C$. By lipase in reverse micellar system containing palm oil and stearic acid, 1,3-dipalmitoyl-2-oleoyl glycerol(POP), 1-palmitoyl-2,3-dioleoyl glycerol(POO) and SOO decreased, but large amounts of 1-palmitoyl-2-oleoyl-3-stearoyl glycerol(POS) and SOS was formed.

• Journal of Environmental Impact Assessment
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• v.28 no.3
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• pp.332-345
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• 2019

The purpose of the study is to evaluate the treatability of contaminated groundwater with TPH and (or) $Cr^{6+}$. Laboratory scale tests were performed for oil/water separation, dissolved air flotation (DAF), coagulation and precipitation, and filtration with sand and activated carbon respectively. Two times of oil/water separation tests for total 40 minutes of separation or separating time shows 90.2 % of TPH removal rate. In case of DAF test for high TPH sample, the TPH removal rates were not varied significantly by the variation of microbubble size. However, tests for low TPH samples show that TPH removal rate increases as microbubbles are smaller. When coagulant was added to sample for DAF test, TPH removal rate was increased 12.3 %. SS removal rate by DAF was 97.9 % at $16-40{\mu}m$ and it was increased as the size of microbubble is reduced. Tests for coagulation and precipitation were performed to evaluate the removal of $Cr^{6+}$ in groundwater. The increase of $FeSO_4$ dosage increased $Cr^{6+}$ removal rate in the coagulation and precipitation process. As the amount of activated carbon in the filter media increased TPH removal rate in the filtration process. SS removal rate by the filtration was 96.7 % similar to the results of DAF process tests. The filtration process treats TPH and SS. Best design parameters are determined as the size of sand is $425-850{\mu}m$ and the ratio of activated carbon and sand is 50:50.