• Journal of the Korean Applied Science and Technology
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• v.7 no.2
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• pp.41-45
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• 1990

A Stability to the dispersion solvent, which is acetonitrile, dichloromethane, benzene, chloroform and acetonitrile-benzene(1:1,v/v) of {N-docosyl pyridinium)-TCNQ(1:2)complex was investigated by U.V Spectrophotometer and was confirmed stabilized on acetonitrile, the dichloromethane and acetonitrile-benzene (1:1,v/v) for seven hours. Using $CdCl_2$buffer solution as subphase for LB films deposition, it was achived successively to fabricate the Y-type LB films of (N-docosyl pyridinium)-TCNQ(1:2)complex. For the sake of verifying the deposition of LB films, U.V is measured by variation of nominal layer number.

• YAKHAK HOEJI
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• v.52 no.4
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• pp.259-263
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• 2008

Anti-inflammatory activity of the extracts of Hibiscus manihot was investigated through the evaluation of its inhibitory effect on the production of inflammatory biomarkers (i-NOS, COX-2) in RAW264.7 murine macrophage cells. Among the sequential solvent fractions (hexane, dichloromethane, ethyl acetate, n-butanol and water), the fractions of dichloromethane (1 ${\mu}g/ml$) and ethyl acetate (5 ${\mu}g/ml$) showed potential inhibitory activities on i-NOS and COX-2 activity in RAW264.7 cells. These results suggest that Hibiscus manihot might have an anti-inflammatory activity through the suppression of inflammatory markers.

• Journal of Environmental Science International
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• v.12 no.1
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• pp.81-86
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• 2003

The study was carried out to evaluate the new analytical method of phthalate esters(diethylphthalate, di-n-butylphthalate, butylbenzylphthalate, bis(2-ethylhexyl)phthalate), one of the endocrine disruptors, which were performed by GC/MS-SIM(selected ion monitoring). The phthalate esters were extracted from water samples using solid-phase extraction on $C_{18}$ columns. It investigated that the extraction recovery rate of phthalate esters with different solvents and solvent volume. The optimal solvent was dichloromethane and proper volume of dichloromethane for recovery of phthalate esters was 4 mL. There were good linearities(above $R^2$=0.9975) in the range 0.01~0.50mg/L, and the detection limits were below 0.01~0.03$\mu\textrm{g}$/L. The recovery rates, RSD and MDLs for phthalate esters were 80~114%, 5.0~8.1% and 0.03~0.11$\mu\textrm{g}$/L, respectively. This method shows a good precision of phthalate esters.

• Journal of Environmental Science International
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• v.6 no.4
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• pp.385-389
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• 1997

Pesticide residues were extracted with 70% acetone and transferred to dichloromethane. Extracts were applied to open-column chromatography with florisil and alumina-N. The final extract was analyzed by gas chromatography with electron-capture detector(GC /ECD) and nitrogen-phosphorus detector(GC/NPD). Recoveries of the 17 organochlorine pegticides were ranged from 60.8 to 84.9% and those of 15 organophosphate pesticides, from 70.5% to 100.0%(except phosmet and azlnphos-methyls. The minimum detectable levels of this analytical method were low(0.021-0.058mg/kg).

• Journal of the Korean Applied Science and Technology
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• v.11 no.2
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• pp.93-97
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• 1994

A Stability to spreading solvent, which is acetonitrile, dichloromethane, benzene, chloroform, and acetonitrile-benzene (1:1, v/v) of (N-docosyl quinolinium)-TCNQ(1:2) complex was investigated by UV-visible spectrometer and was confirmed stabilized on acetonitrile, dichloromethane, and acetonitrile-benzene(1:1, v/v) for 7 hours. Using buffer solution($ph{\doteqdot}6.0$) as subphase for Langmuir-Blodgett(LB) film, it was achieved successively to fabricate the Y type LB films of (N-docosyl quinolinium)-TCNQ(1:2) complex. For the identification of deposition of (N-docosyl quinolinium)-TCNQ(1:2) complex, UV-visible spectra was recorded on HP 8452A spectrometer.

• Journal of environmental and Sanitary engineering
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• v.13 no.1
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• pp.135-146
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• 1998

In this study, we investigated to measured concentration, seasonal characteristics and load quantity of volatile organic compounds(VOCs) for 11 sites in the main stream and 8 sites in the branch stream of Kumho river, during from October 1995 to April 1997. As a results, the small amount of volatile compounds, such as dichloromethane, chloroform, toluene, benzene, trichloroethene, tetrachloroethene, p-xylene and 1,3,5-trimethyl-benzene were detected from the main stream of Kumho river. Also detected to dichloromethene, chloroform, toluene, benzene, trichloroethene, tetrachloroethene, ethylbenzene, p-xylene, 1,3,5-trimethylbebzene and 1,2,4-trimethylbenzene in the branch stream, and dichloromerhane, chloroform and toluene were detected to all site of sampling. And seasonal variation of volatile organic compounds showed higher concentration in the July 1996 as a winter season than January 1997 as a summer season in most places. Also the load quantity of volatile organic compound at Gangchang site in the last downstream of Kumho river, was in order of chloroform > dichloromethane > toluene > trichloroethene.

• Korean Journal of Pharmacognosy
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• v.28 no.1
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• pp.54-58
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• 1997

The cytotoxic activities of methanolic extract and its fractions of Ailanthi Cortex Radicis and column chromatographic eluates of its dichloromethane fraction (DCM fr.) were investigated. DCM fr. Showed the strongest cytotoxicity against hepatoma cells. Furthermore, the active equates 1-3, 8 and 9 were obtained. Effects on free radical generation and the growth of vascular endothelial cells were tested to elucidate the action mechanism of anticancer activity. Eluates 1-3 stimulated free radical generation, while eluates 8 and 9 showed no changes. Especially, eluates 8 and 9 efffectively inhibited the proliferation of vascular endothelial cells in a dose- dependant manner. It is speculated that the anticancer effects of eluates 1-3, 8 and 9 might be due to free radical generation and inhibition of endothelial cell growth, respectively.

• Carbon letters
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• v.11 no.1
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• pp.13-21
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• 2010

Coconut shell activated carbon (CSAC) was investigated for its ability in the removal of two neutral chlorinated organic compounds, namely trichloroethylene (TCE) and dichloromethane (DCM) from aqueous solution using a packed bed column. The efficiency of the prepared activated carbon was also compared with a commercial activated carbon (CAC). The important design parameters such as flow rate and bed height were studied. In all the cases the lowest flow rate (5 mL/min) and the highest bed height (25 cm) resulted in maximum uptake and per cent removal. The experimental data were analysed using bed depth service time model (BDST) and Thomas model. The regeneration experiments including about five adsorption-desorption cycles were conducted. The suitable elutant selected from batch regeneration experiments (25% isopropyl alcohol) was used to desorb the loaded activated carbon in each cycle.

• Membrane Journal
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• v.9 no.1
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• pp.1-9
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• 1999

Sulfonated polyetherimide having anionic charge and better hydrophilicity than polyetherimide was prepared by reacting polyetherimide with chlorosulfonic acid. To prepare casting solution, from which the membrane having good performance can produce. Polyvinylpyrrolidone as a pore forming agent and volatile weak solvent such as dichloromethane to foml the dense skin layer were added to the sulfonated polyetherimide / N -methyl-2-pyrrolidone solution. Membrane fabricated sulfonated PEl showed better fouling resistance to the protein than those fabricated PEL because of its hydrophilicity. Solute having negative charge was removed effectively with membrane fabricated from the sulfonated PEl because of its the same electron charge.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2065-2068
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• 2007

The nanoscale morphologies on a series of new anthraquinone substitutes have been carried out. Among the substitutes, only bis[2-(1-anthraquinonoxy)-ethyl]ether in a mixture of dichloromethane/acetone (1/1) slowly forms uniform nanowires with 80-120 nm diameters. The same compound in a mixture of dichloromethane/tetrahydrofuran (1/1) slowly produces uniform nanobelts with 400-600 nm widths. Thus, both the spacer lengths and the solvent effects of the compounds are important factors for the formation of nanoscale morphologies. The nano patterns seem to be formed by the π-π interactions between the anthraquinone moieties.