• Journal of the Korean Chemical Society
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• v.54 no.4
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• pp.414-418
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• 2010

Ethyl 1-aminotetrazole-5-carboxylate (1) reacted with hydrazine hydrate to give the corresponding aminohydrazide 2. Cyclization of 2 by carbon disulfide yielded 1,3,4-oxadiazole-5-thiol structure 3. Reaction of 3 with either chloroacetone or ethyl chloroacetate furnished S-acyl 1,3,4-oxadiazole derivatives 4 and 5, respectively. Also compound 3 reacted with hydrazine hydrate afforded 4-amino-1,2,4-triazole-5-thiol derivative 6. 6-Methyl-1,3,4-triazolo[3,4-b]-1,3,4-thiadiazole structure 7 was synthesized by reaction of aminothiol 6 with glacial acetic acid. Diazotization of 1 with sodium nitrite in presence of hydrochloric acid yielding the diazonium salt which on treating with hippuric acid, oxazolone derivative 8 was obtained. Furthermore, tetrazolo[5,1-f]-1,2,4-triazine 9 was constructed via cyclization of aminoester 1 with formamide. Compound 9 reacted with carbon disulfide to furnish 8-thione derivative 10 which reacting with chloroacetone, ethyl chloroacetate, and hydrazine hydrate, the corresponding chemical structures 11, 12, and 13 were synthesized. 1,2,4-Triazolo[4,3-d]tetrazolo[5,1-f]-1,2,4-triazines 14 and 15 were resulted by treating of compound 13 with triethyl orthoformate, and glacial acetic acid, respectively. The structures of the newly synthesized products were elucidated according to elemental analyses and spectroscopic evidences. Some of the representative members of the prepared compounds were screened for antimicrobial activity.

• Journal of Microbiology and Biotechnology
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• v.30 no.6
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• pp.839-847
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• 2020

In the present study, an anaerobic microbial consortium for the degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was selectively enriched with the co-addition of RDX and starch under nitrogen-deficient conditions. Microbial growth and anaerobic RDX biodegradation were effectively enhanced by the co-addition of RDX and starch, which resulted in increased RDX biotransformation to nitroso derivatives at a greater specific degradation rate than those for previously reported anaerobic RDX-degrading bacteria (isolates). The accumulation of the most toxic RDX degradation intermediate (MNX [hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine]) was significantly reduced by starch addition, suggesting improved RDX detoxification by the co-addition of RDX and starch. The subsequent MiSeq sequencing that targeted the bacterial 16S rRNA gene revealed that the Sporolactobacillus, Clostridium, and Paenibacillus populations were involved in the enhanced anaerobic RDX degradation. These results suggest that these three bacterial populations are important for anaerobic RDX degradation and detoxification. The findings from this work imply that the Sporolactobacillus, Clostridium, and Paenibacillus dominant microbial consortium may be valuable for the development of bioremediation resources for RDX-contaminated environments.

• Archives of Pharmacal Research
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• v.15 no.1
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• pp.14-19
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• 1992

Diazotized primary artomatic amines 4 coupled with the ketosulfones 1-3 in ethanol in the presence of sodium acetate at $0^\circ{C}$ to afford the corresponding bydrazones 5-7. Also diazotized 3-aminopyrazoles 14 coupled with 1-3 in ethanolic sodium acetate to give the pyrazolotriazines 18-20 in good yields. Compounds 5-7 and 18 can also be obtained from the reaction of hydraziodoyl halides 8-10 and 21 with sodium benzenesultinate. The hydrazones 11-13 can easy be oxidized to the hydrazones 5-7, using hydrogen peroxide in acetic acid.

• The Journal of Information Technology
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• v.8 no.4
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• pp.43-50
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• 2005

In this paper, we describe a study on the relationship between photographic emulsion manufacture and hardening test of color paper. The hardener was prepared by the reaction of cyanuric chloride with sodium hydroxide, disodium hydrogenphosphate-12-water and trisodium phosphate-12-water in the presence of water. The hardener used in this study is a 2,4-dichloro-6-hydroxy-1,3,5-triazine mono sodium salt. The hardening test of photographic emulsion was studied respectively at pH 5.5, 7, 8.5 and about increasing temperature. Novel hardener can be used in photo-graphic emulsion of color paper and showed very good hardening effect.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.498-504
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• 1996

The synthesis of carbon nitride thin films with high nitrgen concentration was accomplished by reactive supttering at relatively high working pressure. In conventional reactive sputter-deposition of carbon nitride films, working pressure was 0.3-5Pa and the ratio of nitrogen to carbon(N/C ratio) in the films was less than 0.5. In this study, amorphous carbon nitride films with the N/C ratio $\tickapprox$ 1.0 were prepared on Si(100). substrates at higher pressure, 20-60 Pa. Structural analyses with Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy revealed that the films prepared consisted of triazine-like plain network.

• Bulletin of the Korean Chemical Society
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• v.24 no.8
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• pp.1181-1187
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• 2003

Condensation of 4-cyano-5,6-dimethyl-3-pyridazinone 1 with aromatic aldehydes gave the novel styryl derivatives 2a-c. Refluxing of compound 2a with phosphorus oxychloride furnished 3-chloropyridazine derivative 3. Compound 3 was reacted with thiourea and produced pyridazine-3(2H)thione 4. Thieno[2,3-c]- pyridazines 5a-e were achieved by cycloalkylation of compound 4 with halocompounds in methanol under reflux and in the presence of sodium methoxide. Also, refluxing of compound 4 with N-substituted chloroacetamide in the presence of potassium carbonate afforded thienopyridazines 6a-e. Cyclization of compound 6 with some electrophilic reagents as carbon disulfide and triethyl orthoformate furnished the novel pyrimido[4',5':4,5]thieno[2,3-c]pyridazines 12 and 13a-c, respectively. Diazotisation of compound 6 with sodium nitrite in acetic acid produced the pyridazino[4',3':4,5]thieno[3,2-d][1,2,3]triazines 14a-c. Ternary condensation of compound 1, aromatic aldehydes and malononitrile in ethanol containing piperidine under reflux afforded the novel phthalazines 16a-c. Compound 3 was subjected to some nucleophilic substitution reactions with amines and sodium azide and formed the aminopyridazines 17a, b and tetrazolo[1,5-b]-pyridazine 19, respectively. The structures of the synthesized compounds were established by elemental and spectral analyses.

• Bulletin of the Korean Chemical Society
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• v.31 no.7
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• pp.1976-1980
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• 2010

A simple and reliable method has been developed to selectively separate and concentrate trace amounts of Fe(III) ions from water and food samples by using flame atomic absorption spectrometry. A new reagent, 5-hydroxy-4-ethyl-5,6-di-pyridin-2-yl-4,5-dihydro-2H-[1,2,4] triazine-3-thione, was synthesized and characterized by using FT-IR spectroscopy and elemental analysis. Effects of pH, concentration and volume of elution solution, sample flow rate, sample volume and interfering ions on the recovery of Fe(III) were investigated. The optimum pH was found to be 5. Eluent for quantitative elution was 10 mL of 2 M HCl. The preconcentration factor of the method, detection limit (3s/b, ${\mu}gL^{-1}$) and relative standard deviation values were found to be 25, 4.59 and 1%, respectively. In order to verify the accuracy of the method, two certified reference materials (TMDA 54.4 lake water and SRM 1568a rice flour) were analyzed. The results obtained were in good agreement with the certified values. The method was successfully applied to the determination of Fe(III) ions in water and food samples.

• Journal of Korean Society on Water Environment
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• v.18 no.2
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• pp.113-122
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• 2002

A bench-scale anoxic membrane bioreactor (MBR) system, consisting of a bioreactor coupled to a ceramic crossflow ultrafiltration module, was evaluated to treat a synthetic wastewater containing alkaline hydrolysis byproducts (hydrolysates) of RDX, The wastewater was formulated the same as RDX hydrolysates, and consisted of acetate, formate, formaldehyde as carbon sources and nitrite, nitrate as electron accepters. The MBR system removed 80 to 90% of these carbon sources, and approximately 90% of the stoichiometric amount of nitrate, 60% of nitrite. The reactor was also operated over a range of transmembrane pressures, temperatures, suspended solids concentration, and organic loading rate in order to maximize treatment efficiency and permeate flux. Increasing transmembrane pressure and temperature did not improve membrane flux significantly. Increasing biomass concentration in the bioreactor decreased the permeate flux significantly. The maximum volumetric organic loading rate was $0.72kg\;COD/m^3/day$, and the maximum F/M ratio was 0.50 kg N/kg MLSS/day and 1.82 kg COD/kg MLSS/day. Membrane permeate was clear and essentially free of bacteria, as indicated by heterotrophic plate count. Permeate flux ranged between 0.15 and $2.0m^3/m^2/day$ and was maintained by routine backwashing every 3 to 4 day. Backwashing with 2% NaOCl solution every fourth or fifth backwashing cycle was able to restore membrane flux to its original value.

• Korean Journal of Microbiology
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• v.36 no.3
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• pp.209-215
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• 2000

The purpose of U7is work was to iilvestigate the degradation of s-h~azine hel-hicidcs, ahilzine and simazine by TNT-degrader under several relevaut physicochemical environ~nental parameters. TNT-degrader showed effective degradability of atrazine and snnazine as well. Both atrazme (GO 1i1~11) and simazine ( 4 5 rng//) were completely degraded within 30 hrs and 4 days of incubation, respectively. As d ~ e concentrations of atrazine and sunazine increased in the media, the degradation ofthose compounds were delayed. Additional caubans were essential to degrade atrazine and simazule, and no degradation was achieved in the absence of additional carbons. The effect of supplemented nitrogens on the degradation of atrazine and sunazine was evalualed. Addition of a suppleinented nitrogen in he growth medium containing ah-azine or siinazine showed partial degr-adation olihose herbicides duriug the incubation period. However, complete degradation of atrazine and simazu~e was examined ul the absence or any supplemented nitrogens. Addltion of yeast extract in this study was inhibilory to atrazine aud siinazine degradations, respectively. TNT-degrader was a small Gram-negative cocco-bacillus. Physiological analysis using BIOLOG sysleln revealed that this strain was Ste~~ol~~opl~orno~~ns rrialtophilia.

• Bulletin of the Korean Chemical Society
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• v.26 no.4
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• pp.599-602
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• 2005

The aromatic fluorination method involving the acid-catalyzed decomposition of a triazene in an ionic liquid is a very convenient and efficient way to prepare a variety of aromatic fluorides in a lab-scale. It should be particularly useful for the preparation aryl fluorides substituted with electron withdrawing substituents. Fluorination of triazene 1 (1.0 mmol) and p-toluenesulfonic acid (1.2 mmol) in an ionic liquid, 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][$BF_4$], 2.5 mL) proceeds very smoothly at 80 ${^{\circ}C}$ with or without an external source of fluoride, providing 73% yield in 30 min. Unlike diazonium salts, triazene precursors are stable enough to be stored for a long period of time without a noticeable decomposition.