• Membrane Journal
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• v.24 no.4
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• pp.317-324
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• 2014

It is very well known that the conventional polyamide (PA) thin film composite (TFC) reverse osmosis (RO) membranes have excellent permselective properties, but their chlorine tolerance is not good enough. In this study, to improve such chlorine tolerance, microporous membranes containing hydrophilic functional groups such as -COOH were used as a support to prepare PA TFC RO membranes, employing the conventional interfacial polymerization method. Meta-phenylene diamine (MPD) and 2,6-diamine toluene (2,6-DAT) were used as diamine monomers and tri-mesoyl chloride (TMC) as an acid monomer. The membranes prepared were characterized using various instrumental analytical methods and permeation test set-up. The flux obtained from the membranes prepared so was more than $1.0m^3/m^2day$ at 800 psi of operating pressure, while the salt rejection was over 99.0%. The chlorine tolerance of them was also found to be better than that of the membrane prepared by using conventional polysulfone support without hydrophilic functional groups.

• Membrane Journal
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• v.9 no.2
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• pp.132-139
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• 1999

Solid scintillation proximity membranes were prepared for measuring the amount of radioactivity in laboratories contaminated by the radionuclide of $^3H$-cortisol. The membranes, consisting of polysulfone as a polymer matrix and cerium activated yttrium silicate as a fluor, were used to monitor the amount of radioactivity without the aid of a scintillation cocktail required for the conventional wipe test. The test results of the cocktail-free wipe test showed that the prepared membranes were efficient to monitor radionuclide-contaminated areas with the good counting ability as well as with the decrease of overall production of radioactive waste. On the other hand, solvent treatment of the prepared membranes could induce a significant variation of membrane morphology, but the counting efficiency of the solvent-treated membranes was not improved than that of the untreated one.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.12
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• pp.1105-1112
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• 2009

Antibiotics are biologically active substances and commonly used for therapeutic treatment of infectious disease in humans and for treating and protecting the health of animals. In recent years, antibiotics have attracted worldwide attention because of their side effects on the environment. Consequently, efforts have been made to monitor the residual of antibiotics in the environment. This study tested the mobility of tetracyclines and sulfonamides in soil and leachate through column experiments. The three tetracycline antibiotics showed higher mass recovery rates in all kinds of soils(28.00~44.11%) than in leachate(10.54~27.43%). This seems attributable to the high adsorption coefficient values($K_d$) of tetracyclines representing strong and active adsorbability to organic and mineral phases in soil, ending up relatively small amount being detected in surface water. By contrast, the sulfonamides(sulfamethazine and sulfathiazole) showed higher mass recovery rates in leachate(23.19~26.20%) compared to in soil(10.41~14.21%) due to lower adsorption coefficient values and higher mobility of sulfonamides, enabling easier movement to surface water through the runoff in the environment.

• Membrane Journal
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• v.14 no.2
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• pp.126-131
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• 2004

The surface of dense polysulfane films was modified through solvent treatment. The modification process consisted of dipping a film for one second in dimethylformamide and then immersing it Into a nonsolvent bath. After being solidified, the original transparent film transformed into an opaque white one, which is due to the light scattering on pores newly developed on the surface. The surface roughness entailing the pore formation was more explicit on a film coagulated by water as nonsolvent than on a film coagulated by isopropanol. The surface-modified films show the better pick-up efficiency than a conventional filter paper on the detaching of radioactive contaminants on the contaminated area. The pick-up efficiency of the film prepared by the water immersion process was superior to that of the film prepared in the isopropanol bath, which was consistent with the surface roughness result. The surface-modified films kept the dense inner structure, playing a major role preventing a possible secondary contamination during the pick-up process.

• Clinical and Experimental Pediatrics
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• v.49 no.3
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• pp.332-336
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• 2006

Toxic epidermal necrolysis (TEN) is a rare, acute and life-threatening cutaneous drug reaction. TEN is characterized by the sudden onset of extensive necrosis in the epidermis and frequent mucous membrane involvement. The pathogenesis has not yet been elucidated. In addition, no particular treatment for TEN has been established. We report a case of TEN in a 14-year-old-boy, which might have been caused by steroids with enalapril treatment for membranous nephropathy. He recovered after intravenous immunoglobulin therapy.

• Journal of Energy Engineering
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• v.13 no.2
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• pp.93-100
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• 2004

The smear media possible to sampling and radiation detection was prepared and evaluated for the surface contamination using indirect method. The films were made by impregnating Cerium Activated Yttrium Silicate (CAYS) in a polysulfone membrane. The membranes used solution as a dimethylformamide (DMF) and methylene chloride (MC), polysulfone as a polymer matrix and CAYS as a inorganic scintillator. The proximity membranes were prepared with single- and double-layered structure. The solidified methods were immersion to the nonsolvent bath such at water and ethanol and solvent evaporation. The measurement of the photon produced by interaction with radiation and inorganic scintillator used a photomultiflier tube (PMT), amplifier, and counter. In the comparison with the low background alpha/beta counter, the counter rate using inorganic scintillator proximity membrane for the $\^$14/C surface contamination was about 50%. Also. the $^3$H counting results revealed that the prepared membranes were efficient to monitor the surface contaminated with the low energy be-ray emitter nuclides.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.3
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• pp.278-286
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• 2010

Veterinary antibiotics have been used to treat disease and to promote growth of livestock. However, the total amount of veterinary antibiotics in Korea was much greater than other developed countries, and there is a high potential to release residual of antibiotics to environment. Consequentially, released antibiotics into the environment produces antibiotic resistant bacteria and causes adverse effects on human health. The objective of this research was to monitor antibiotic concentration in the environment adjacent to facilities which compose chicken manure. Total of 10 antibiotics were selected based on the total amount of higher usage in Korea, and its residuals were measured from surface water, soil and sediment. The frequencies of detected antibiotics were ranged 31-92% from soil, 0-93% from water, and 33-93% from sediment. Generally, a higher frequency was observed in soil or sediment than water. Different ranges in concentration among 4 different antibiotic groups was found from not detected(N.D.) to 35.6 ${\mu}g/kg$ for soil, N.D. to 19.2 ${\mu}g/L$ for water and N.D. to 114.3 ${\mu}g/kg$ for sediment. Our findings suggest that solid phase such as soil and sediment is a critical component to be needed to conduct the environmental impact assessment of antibiotics.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.10
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• pp.845-854
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• 2009

There has been increased concern regarding the release of antibiotics to different environmental compartments due to the possibility of the development of antibiotic resistant bacteria. However, limited information is available regarding the occurrence, fate, and transport of antibiotics in Korea in both the aqueous phase and in solid phases such as sediment and soil. Therefore, this study was conducted to monitor the concentration of released antibiotics in surface water, sediment, and soil adjacent to a cattle manure composting facility in Korea. Specifically, the following six antibiotics were monitored: tetracycline (TC), chlortetracycline (CTC), oxytetracycline (OTC), sulfamethazine (SMT), sulfamethoxazole (SMX), and sulfathiazole (STZ). To extract and quantify the antibiotics from different environmental compartments, solid phase extraction (SPE) and high performance liquid chromatography mass spectrometry (HPLC/MS) techniques were adopted. The concentration of the six antibiotics ranged from below the detection limit (BDL) to 0.71 ${\mu}g$/L in surface water, from BDL to 27.61 ${\mu}g$/L in sediment, and from 0.12 to 157.33 ${\mu}g$/L in soil. In addition, higher concentrations of antibiotics were observed in surface water and sediment at locations closer to the composting facility indicating that composting is the source of the antibiotics found in the environment. Furthermore, higher concentrations of antibiotics were observed in the solid phase (sediment and soil) than the aqueous phase. These findings indicate that the possibility of antibiotic resistant bacteria is increased because such bacteria are more stable in the solid phase. Overall, longterm monitoring of the aqueous phase and solid phase is necessary to gain a better understanding of the impact of antibiotics from source on the environment in Korea.