• Proceedings of the Korean Environmental Health Society Conference
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• 2004.06a
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• pp.160-164
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• 2004

This study was carried out to investigate the removal of TNT (2,4,6-trinitrotoluene) and parathion in the batch and the continuous constructed wetland microcosms consisting of marsh and pond. The batch system study showed that TNT was almost reduced in the marsh and pond system within 20 days and parathion was within 8 days. The major reductive metabolites of TNT includes 2,4-diamino-6-nitrotoluene (24DANT) >2,6-diamino-4-nitrotoluene (26DANT) >4-diamino-2,6-nitrotoluene(4ADNT) > 2-diamino-4,6-nitrotoluene (2ADNT), and the concentrations of these metabolites were decreased during further operation. The generation rates of 4-nitrophenol, the major metabolite of parathion, were 82% and 15% in the bottom of marsh and pond system, respectively. In the continuous system study, although TNT/parathion degradation pattern was similar to the batch's, marsh-pond system showed the most stable TNT/ parathion removal among various continuous reactor combinations.

• Journal of Environmental Science International
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• v.7 no.4
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• pp.541-548
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• 1998

Aqueous phase adsorption of phenols by granular activated carbon was studied in a batch adsorption vessel. Adsorption Isotherms of phenol(Ph), p-chlorophenol(PCP) and p-nitrophenol (PNP) from aqueous solution on granular activated carbon have been obtained. The experimental data were analyzed by the surface and pore diffusion models. Both models could be applied to predict the adsorption phenomena. However, the pore diffusion model was slightly better than the surface diffusion model In representing the experimental data for the initial concentration changes. Therefore, the pore diffusion model was used to predict the change of operating variables such as the agitation speed and Particle size of adsorbent which have influence on the film resistance and intraparticle diffusion.

• Bulletin of the Korean Chemical Society
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• v.35 no.7
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• pp.1970-1972
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• 2014

A facile and efficient synthesis of dronedarone hydrochloride starting from commercially available 4-nitrophenol is described. This approach features a tandem-type synthesis of 3-carbonylated benzofuran involving cyclization of 2-ethynylphenol followed by $CO_2$ fixation at the 3-position of the benzofuran ring mediated by potassium carbonate without the addition of any transition metal catalyst.

• Journal of the Korean Chemical Society
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• v.33 no.4
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• pp.406-412
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• 1989

Indirect photometric detection of aliphatic compounds such as alcohols, ketones and esters was investigated in high-performance liquid chromatography, These samples possessing nonchromophore or weak chromophore could be indirectly detected by a UV detector with addition of UV absorbing, p-chlorophenol or p-nitrophenol in mobile phase as detection reagent, and submicrogram detection limits were achieved. Some mixtures of samples were also able to be separated and quantitated with good resolution and comparatively high sensitivity under optimum conditions.

• Journal of Environmental Health Sciences
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• v.36 no.3
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• pp.222-228
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• 2010

Biological degradation of nitrogen-containing aromatic compounds was investigated in activated sludge previously adapted to mineralize low concentrations of nitrogen-containing aromatic compounds. Normally, the time required for 95% degradation of 10 mg/l dinitrophenol (DNP) under aerobic conditions was less than 4 hours without any lag, and with mixed liquor suspended solid (MLSS) levels from 600 to 1,000 mg/l. However, when the initial DNP concentration was increased to 75 mg/l, lags and even complete inhibition of DNP degradation were observed. The length of the lag was found to increase proportionally with decreasing MLSS levels. When dilute activated sludge was incubated for extended periods (192 hours), degradation of 75 mg/l DNP did eventually occur after lag periods of 37 to 144 hours, depending on the MLSS concentration. DNP was degradable in high concentrations if MLSS concentrations were sufficiently high to allow growth of bacteria resistant to the toxic effects of DNP.

• Korean Journal of Microbiology
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• v.3 no.1
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• pp.18-23
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• 1965

It seems like that the characteristics and drug-resistances of fungi are respectively different in various circumstances. Scores of chemicals were applicated to the leather-fungi in this study. M-dinitrobenzene, 2, 4-dinitrochlorobenzene and phenyl mercuric acetate inhibited the growth of Aspergilli which were isolated from Korean-leather. The minimum fungicidal limits of p-nitrophenol, 8-hydroxyquinoline and sodium-pentachlorophenolate against the Korean-originated strains are different from that of other country. In the mass-screening of fungicides, artificial "Leather-extracts media" have been designed and used, and the media contributed to screening-tests. Fat and oils which are the materials of fat-liquoring in leather manufacture affects the drugresistance of the leather-fungi. It is found that the accelerating-method on malt-agar plate is effective to determinate the fungicidal action of chemicals in short time.hort time.

• Carbon letters
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• v.6 no.2
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• pp.89-95
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• 2005

Crushed peach stone shells were impregnated with $H_3PO_4$ of increasing concentrations (30-70%) followed by heat treatment at 773 K for 3 h. Produced carbons (ACs) were characterized by $N_2$ adsorption at 77 K using the BET-equation and the ${\alpha}$-method. High surface area microporous ACs were obtained, with enhanced internal pore volume, as function of % $H_3PO_4$. Adsorption isotherms from aqueous solution were determined for methylene blue (MB) and p-nitrophenol (PNP), as representatives for dye and phenolics pollutant molecules. Application of the Langmuir model proved the high limiting capacity towards both solute molecules, MB was uptaken in increasing amounts as function of $H_3PO_4$ concentration and generated porosity. High removal of PNP was almost the same irrespective of porosity characteristics. Competitive adsorption of $H_2O$ molecules on the hydrophilic carbon surface seems to partially reduce the available area to the PNP molecules. Application of the pseudo-second order law described well the fast adsorption (${\leq}$ 120 min) at two initial dye concentrations.

• Elastomers and Composites
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• v.51 no.4
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• pp.286-300
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• 2016

$MoS_2$ precursors were synthesized by reacting thioacetamide ($C_2H_5NS$) with sodium molybdate dihydrate ($Na_2MoO_4{\cdot}2H_2O$) in aqueous HCl solution. $MoS_2$ nanoparticles were prepared from dried $MoS_2$ precursors by calcination in an electric furnace at $700^{\circ}C$ for 2 h under an inert argon atmosphere. $MoS_2-C_{60}$ nanocomposites were obtained by heating $MoS_2$ nanoparticles and fullerene ($C_{60}$) together in an electric furnace at $700^{\circ}C$ for 2 h. Their morphological and the structural properties were characterized by powder X-ray diffraction and scanning electron microscopy. The $MoS_2$ nanoparticles and $MoS_2-C_{60}$ nanocomposites were used as catalysts in the reductions of 2-, 3-, and 4-nitrophenol in the presence of sodium borohydride. The photocatalytic activities of the $MoS_2$ nanoparticles and $MoS_2-C_{60}$ nanocomposites were evaluated in the degradation of organic dyes (brilliant green, methylene blue, methyl orange, and rhodamine B) under ultraviolet light (254 nm).

• Composites Research
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• v.32 no.2
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• pp.85-89
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• 2019

The size, morphology and composition of nanoparticles are regarded as the most important factors to the efficiency of catalytic reduction of various chemical compounds. In order to make a systematic comparison, gold, platinum and palladium nanoplates with 100 nm diameter with rough surface morphology were manufactured through the galvanic replacement reaction, and the reaction kinetics of the catalytic reduction of 4-nitrophenol and 4-nitroaniline was systematically analyzed by spectroscopic measurement. According to the observation, the catalytic reduction efficiency was significantly different against the constitutional elements in order of Pd > Au > Pt, and it was additionally influenced by the type of substrate.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.250-257
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• 1997

A new sensing system based on the immobilization of luminescent bacteria, photobacterium phosphoreum, was proposed for continuous real-time monitoring of pollutants. The response curves demonstrate that Photobacterium phosphoreum immobilized on the strontium alginate were very sensitive to seven reference chemicals used. The significant inhibitory concentrations for bioluminescence emission were 5 ppm for Pb$(NO_3)_2$), $NiCl_2$, $CdCl_2$, 50 ppm for $NaASO_2$, 0.1 ppm for $HgCl_2$, 0.5 ppm for pentachlorophenol and less than 5 ppm for SDS, respectively. The alginate mixed-cells (AMC) retained their luminescence during experimental period (29 days) under storage condition of $-80^{\circ}C$. The variables affecting performance of continuous flow through monitoring (CFTM) was optimized in order to ensure stability and efficiency. The flow through cell with strontium-alginate immobilized luminescent bacteria was tested with salicylate and 4-nitrophenol. A rapid response of luminescence was recorded by time drive mode in bioluminescence spectrometer after exposure to both toxicants.