• 대한화학회지
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• 제19권1호
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• pp.38-42
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• 1975

2-Acetothienone과 chloral을 축합시켜 chloral-2-acetothienone을 생성하였으며 이것을 탈수하여 trichloroethylidene-2-acetohienone을 합성하였다. Trichloroethylidene-2-acetothienone과 phenylhydrazine 또는 치환된 phenylhydrazine들과의 반응으로 2-aryl-6-(2-thienyl)-3(2H)-pyridazinone들을 얻었으며 hydrazine과의 반응에서는 3-(2-thienyl)-5-trichloromethyl-2-pyrazoline이 합성되었다.

• Corrosion Science and Technology
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• 제15권2호
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• pp.92-107
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• 2016

Graphene was coated on austenitic and martensitic stainless steels to simulate the metallic bipolar plate of proton exchange membrane fuel cell (PEMFC). Graphene oxide (GO) was synthesized and was reduced to reduced graphene oxide (rGO) via a hydrazine process. rGO was confirmed by FE-SEM, Raman spectroscopy and XPS. Interfacial contact resistance (ICR) between the bipolar plate and the gas diffusion layer (GDL) was measured to confirm the electrical conductivity. Both ICR and corrosion current density decreased on graphene coated stainless steels. Corrosion resistance was also improved with immersion time in cathodic environments and satisfied the criteria of the Department of Energy (DOE), USA. The total concentrations of metal ions dissolved from graphene coated stainless steels were reduced. Furthermore hydrophobicity was improved by increasing the contact angle.

• Mycobiology
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• 제36권1호
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• pp.70-73
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• 2008

The antibacterial and antifungal activities of three schiff bases were evaluated against some pathogenic bacteria and fungi. Parallel experiments were also carried out with standard drugs (Kanamycin for bacteria and Nystatin for fungi). Two compounds [N-(1-phenyl-2-hydroxy-2phenylethylidine)-2',4' dinitrophenyl hydrazine, abbreviated as PDH and N-(2-hydroxy benzylidine)-2'-hydroxy imine, abbreviated as HHP] showed significant antimicrobial activities. The rest one [N-(l-phenyl 2-hydroxy-2 phenyl ethylidine) 2'-hydroxy phenyl imine, abbreviated as PHP] showed moderate activity. All these three compounds were found to possess pronounced cytotoxic effect. These compounds can be considered as potent antimicrobial agents.

• 대한화학회지
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• 제48권6호
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• pp.609-615
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• 2004

간염치료에 탁월한 효과를 나타내는 alkoxyallylthiopyridazine 유도체들이 maleic anhydrides로부터 합성되었다. 수용성 HCl에서 maleic anhydrides를 hydrazine monohydrate로 환류하면 dihydroxypyridazines이 얻어지며, 이 화합물을 phosphorus oxychloride로 반응시키면 dichloropyridazines으로 전환되었다. Dichloropyridazines에서 첫 번째 염소원자의 치환은 THF 용매에서 알코올성 sodium alkoxides에 의하여 선택적으로 일어나 alkoxy- chloropyridazines을 생성하며, 이 화합물은 lithium 2-propene-1-thiolate에 의하여 높은 수득율로 alkoxyallyl- thiopyridazines으로 전환되었다.

• 대한화학회지
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• 제55권2호
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• pp.218-229
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• 2011

Imine 화합물 1을 hydrazine hydrate와 같은 nitrogenous 시약과 반응시켜서 치환된 pyrimidines 화합물을 합성하였다. 얻어진 화합물 2를 다양한 반응조건, 즉 propionic acid, formic acid, ethyl chloroformate, acdetic anhydride, carbon disulphide, cyanogene bromide, triflauroacetic acid 및 ethyl chloroacetate와 반응시켜서 대응하는 화합물을 좋은 수율로 얻었으며, 반응은 Dimroth-type 자리옮김 반응을 통하여 진행되었다.

• 대한화학회지
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• 제55권6호
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• pp.988-993
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• 2011

Cyclodehydration of 6-amino-5-cyano pyrimidine derivative (2) afforded pyrimidoisoindole derivatives (3). Compound (3) reacted with carbethoxymethylene derivative to give pyridopyrimidine derivatives (5a,b). Compound (3) was also reacted with formamide to give the corresponding pyrimidopyrimdine derivatives (6) that condensed with benzaldehyde to give Schiff's base (7). Refluxing of compound (3) with triethyl orthoformate afforded compound (8) that cyclized with ammonium hydroxide giving the same compound (6). Compound (8) cyclized with hydrazine hydrate giving compound (9) which also cyclized with triethyl orthoformate affording compound (10). Diazotization of compound (3) led to the formation of triazinopyrimidine derivative (11). Cyclization of compound (11) upon treatment with hydrazine hydrate afforded compound (12). Compound (15) was prepared from reaction of compound (3) and ethylenediamine in presence of carbon disulfide. The behaviour of compound (15) toward benzoyl chloride, triethyl orthoformate, nitrous acid and/or carbon disulfide was also described. All proposed structures were supported by elemental analyses, spectroscopic data and some of the new products showed antimicrobial activity.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.257-261
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• 2004

Computational fluid dynamics analysis was carried out for thermo-chemical flow field in Arcjet thruster with mono-propellant Hydrazine ($N_2$H$_4$) as a working fluid. The theoretical formulation is based on the Reynolds Averaged Navier-Stokes equations for compressible flows with thermal radiation. The electric potential field governed by Maxwell equation is loosely coupled with the fluid dynamics equations through the Ohm heating and Lorentz force. Chemical reactions were assumed being infinitely fast due to the high temperature field inside the arcjet thruster. An equilibrium chemistry module for nitrogen-hydrogen mixture and a thermal radiation module for optically thin media were incorporated with the fluid dynamics code. Thermo-physical process inside the arcjet thruster was understood from the flow field results and the performance prediction shows that the thrust force is increased by amount of 3 times with 0.6KW arc heating.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제22회 춘계학술대회논문집
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• pp.137-141
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• 2004

Many monopropellant thrusters use a catalyst for decompose the propellant, hydrazine. The catalyst directly affects the thruster performances and lifetime. Therefore, it is important to confirm that the catalyst is suitable for our thrusters. Until 2002, we used She1l405 catalyst, for satellite RCS thrusters, and H-IIA and M-V launch vehicle upper-stage RCS thrusters. In 2002, however, Shell Chemical Inc. ceased manufacturing She1l405 catalyst and transferred the product to AEROJET, where it was renamed S405. We subsequently investigated the characteristics of AEROJET's S405 catalyst and SOLVAY's KC12GA catalyst, (SOLVAY is a Belgian chemical company, and KC12GA is used for ASTRIUM's thruster) and conducted thruster firing tests using the new catalysts. After conducting, we confirm that the KC12GA catalyst was suitable for our thrusters, and decided to use KC12GA for two satellite programs.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2004년도 제23회 추계학술대회 논문집
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• pp.292-295
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• 2004

위성 및 발사체의 자세제어용으로 사용되는 단일 추진제 추력기에 사용되는 하이드라진 분해 촉매의 연소성능을 실제 연소시험을 통하여 확인하였다. 촉매연소성능을 확인하기 위한 촉매 시험 장치를 설계/제작하여 국산화하였으며 이를 통하여 하이드라진 분해촉매의 연소지연시간, 촉매활성도, 촉매안정도의 촉매 연소특성을 평가, 분석하였다.

• Nuclear Engineering and Technology
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• 제54권9호
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• pp.3580-3585
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• 2022

The thermal stability of carbohydrazide, hydrazine nitrate, acetohydroxamic acid in nitric acid solutions has been studied at atmospheric pressure and above atmospheric pressure. The volumes of gaseous products of thermolysis and the maximum rate of gas evolution have been determined at atmospheric pressure. It has been shown that, despite the high rate of gas evolution and large volumes of evolved gases, the conditions for the development of autocatalytic oxidation are not created. Exothermic processes are observed in a closed vessel in the temperature range of 50-250 ℃. With an increase in the concentration of nitric acid, the temperatures of the onset of exothermic effects for all mixtures decrease, and the values of the total thermal effects of reactions increase, to the greatest extent for solutions with carbohydrazide.