• Journal of Environmental Science International
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• v.11 no.6
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• pp.561-567
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• 2002

This study was investigated to evaluate the effect of the sodium ion and pH on toxicity of dinitrophenol at high concentrations (0.41 to 0.54 mM), over a sodium concentration range of 0.1 mM to 107 mM and over a pH range of 5 to 9. The concentration of sodium ions in the activated sludge mixed liquor seemed to have very little effect on dinitrophenol toxicity. However, lack of sodium in the growth media resulted in a reduction of the dinitrophenol degradation rate by bacterial isolate from the activated sludge culture, which has been identified as Nocardia asteroides. Dinitrophenol inhibition was found to be strongly dependent on mixed liquor pH. The dinitrophenol degradation rate was highest in the pH range of 6.95 to 7.84; at pH 5.94 degradation of 75 mg/L dinitrophenol was significantly inhibited; at pH < 5.77, dinitrophenol degradation was completely inhibited after approximately 30% of the dinitrophenol was degraded.

• 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.

• Journal of Microbiology and Biotechnology
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• v.7 no.4
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• pp.242-249
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• 1997

Stability of bioluminescence was investigated with Photobacterium phosphoreum immobilized on the strontium alginate in order to develope continuous real time monitoring of pollutants. The stability of bioluminescence emission was improved by prolonged aging time. The aging time of ${\geq}40$ min and the cell concentration of ${\leq}0.6\;of\;OD_660$ were selected for the immobilization of P. phosphoreum to give linearity between cell concentrations and bioluminescence intensity. In sensitivity tests using phenol, it was found that this compound quenched bioluminescence proportional to the concentration without lowering of cell growth. The lower value for maximum quenching ($q_s$) and higher dissociation constant ($K_s$) were observed with strontium-alginate immobilized cells compared to free cells. The response of bioluminescence to toxicants was evaluated with the immobilized luminescent bacteria. The sensitivity of the immobilized cells was found to be good in response to toxicants, 4-nitrophenol, salicylate and cadmium, when evaluated with a specific rate of bioluminescence quenching.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.2
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• pp.127-137
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• 2002

Phenolic compounds in air are toxic even at their low concentrations. We had evaluated a total of five phenolic compounds (Phenol, o-Cresol, m-Cresol, 2-Nitrophenol and 4-Chloro-3-methylphenol) in artificial air using a combination of ATD/GC/MS. To compare the adsorption efficiency of these phenolic compounds, three adsorbents (Tenax TA, Carbotrap and Carbopack B) were tested. Tenax TA adsorbent was most effective of all the adsorbents used for the efficiency test. Five phenolic compounds were found to be very stable on adsorbent tubes for 4 days at room temperature. Detection limit of five phenolic compounds ranged from 0.05 to 0.08 ppb (when assumed to collect 10 L air). The calibration curve was linear over the range of 22∼ 164 ng. The reproducibility was less than 4%. Sampling of duplicate pairs (DPs) was made to demonstrate duplicate precision and sampling efficiency.

• 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.

• Toxicological Research
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• v.22 no.1
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• pp.1-8
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• 2006

The primary metabolism of pyribenzoxim was studied in rat liver microsomes in order to identify the cytochrome P450 (CYP) isoform(s) and esterases involved in the metabolism of pyribenzoxim. Chemical inhibition using CYP isoform-selective inhibitors such as ${\alpha}$-naphthoflavone, tolbutamide, quinine, chlorzoxazone, troleandomycin, and undecynoic acid indicated that CYP1A and CYP2D are responsible for the oxidative metabolism of pyribenzoxim. And inhibitory studies using eserine, bis-nitrophenol phosphate, dibucaine, and mercuric chloride indicated pyribenzoxim hydrolysis involved in microsomal carboxylesterases containing an SH group (cysteine) at the active center.

• 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.

• BMB Reports
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• v.37 no.6
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• pp.642-647
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• 2004

The lysine residues of Bacillus licheniformis $\alpha$-amylase (BLA) were chemically modified using citraconic anhydride or succinic anhydride. Modification caused fundamental changes in the enzymes specificity, as indicated by a dramatic increase in maltosidase and a reduction in amylase activity. These changes in substrate specificity were found to coincide with a change in the cleavage pattern of the substrates and with a conversion of the native endo- form of the enzyme to a modified exo- form. Progressive increases in the productions of $\rho$-nitrophenol or glucose, when para nitrophenyl-maltoheptaoside or soluble starch, respectively, was used as substrate, were observed upon modification. The described changes were affected by the size of incorporated modified reagent: citraconic anhydride was more effective than succinic anhydride. Reasons for the observed changes are discussed and reasons for the effectivenesses of chemical modifications for tailoring enzyme specificities are suggested.

• YAKHAK HOEJI
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• v.19 no.2
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• pp.101-110
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• 1975

p-Chloronitrobenzene(substrate) and p-nitrophenetole (product) were quantitatively analyzed to know the degree of extent of reaction in the process of time. The calibration curve was prepared by the internal satndard method in gaschromatography. 2,6-Dimethyl-naphthalene was used as internal standard. The rate constant(k), the reaction velocity in various concentrations of NaOH altered, and the formation of byproducts(azo-compound and p-nitrophenol) with the amounts of MnO$_{2}$ and NaOH altered, were studied. From the results of these of MnO$_{2}$ and NaOH altered, were studied. From the results of these experiments, this reaction was second order and the rate constant was k=10.3 $\times$ 10$^{-3}$ mole$^{-21$. When p-chloronitrobenaene 1 pt. NaOH 0.56pts. MnO$_{2}$ 0.5pts. and ethanol 25 pts-were reacted about 10 hours, p-nitrophenetole was nearly quantitatively obtained without byproducts.

• 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.