• 한국입자에어로졸학회지
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• 제8권2호
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• pp.69-74
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• 2012

This study describes how successfully a conventional flame aerosol synthesis was used to continuously synthesize Pt-Ru catalysts supported by carbon agglomerates. Nearly spherical catalysts produced in the flame were mainly composed of metallic Pt and Ru with the molar ratio of 1:1 and those sizes were controllable from ~1.5 nm to ~2.0 nm. Nevertheless, only Pt peaks were found from X-ray diffraction experiments, suggesting that amorphous-like Ru was well mixed in the crystalline Pt lattices. It was found from Cyclo-voltamograms and CO stripping experiments that the electrochemical properties of the catalysts are at least comparable to that of a conventional commercial sample.

• 대한기계학회논문집B
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• 제27권10호
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• pp.1480-1488
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• 2003

Synthesis of carbon nanomaterials on a substrate coated with metal nitrates using an ethylene fueled inverse diffusion flame was illustrated. The effects of radial distance, residence time of the substrate, and hydrocarbon composition on the synthesis of carbon nanomaterials were investigated. The effects of catalyst metal particles were also studied using SUS304 substrates coated with Fe(NO$_3$)$_3$ (ferric nitrate, nonahydrate) and Ni(NO$_3$)$_2$(nickel nitrate, hexahydrate), and Cu substrate. Carbon nanomaterials, with diameters ranging from 30 - 70 nm, were observed on the substrate for both cases of using substrates only and using them with metal nitrates. In case of using the substrate with metal nitrates, the formation and growth of carbon nanomaterials were occurred in the lower temperature region than that of using the substrates only due to the easy activation of the metal particles coated on the surface of the substrates.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.1347-1352
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• 2004

In this work, $TiO_{2}$ nanoparticles were synthesized using a $N_{2}-diluted$ hydrogen coflow diffusion flame. The effect of flame temperature on the crystalline structure and the size of formed nanoparticles was investigated. The maximum centerline temperature of the flame ranged from 1,920K for $H_{2}-only$ flame to 863K for 81% $N_{2}-diluted$ flame. When the temperature was higher than about 1,000K, the particle size was tend to increase due to the agglomeration and sintering among the primary particles. On the other hand, when the temperature was lower than 1,000K, the portion of anatase phase was greater than 80%.

• 한국전기전자재료학회논문지
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• 제20권2호
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• pp.142-151
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• 2007

Non-halogen flame retardant have been focus of extensive research because of environmental problem. Hexakisphenokycyclotriphosphazene was synthesized in order to use as the flame retardant of ABS resin. And using bisphenol A, bisphenol S, and resorcinol, the polymers which contained cyclophosphazene structure were synthesized in order to also use as the flame retardants of ABS resin. All of the synthesized polymers themselves got the excellent flame retardancy. And as the molecular weight of the compound were increased, the thermal stability was increased. But when the synthesized compounds were used as the flame retardants for ABS resin, the lower molecular weight compound in these compounds showed the better flame retardancy and the better physical properties of ABS resin. In case of using resorcinol, it showed the best flame retardancy.

• 대한기계학회논문집B
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• 제33권2호
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• pp.116-123
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• 2009

Carbon black, activated carbon and carbon nanotube have been used as supporting materials for precious metal catalysts used in fuel cell electrodes. One-step flame synthesis method is used to coat 2-5nm Pt dots on flame-generated carbon particles. By adjusting flame temperature, gas flow rates and resident time of particles in flame, we can obtain Pt/C nano catalyst-support composite particles. Additional injection of hydrogen gas facilitates pyrolysis of Pt precursor in flame. The size of as-incepted Pt dots increases along the flame due to longer resident time and sintering in high temperature flame. Surface coverage and dispersion of the Pt dots is varied at different sampling heights and confirmed by Transmission electron microscopy (TEM), Energy-dispersive spectra (EDS) and X-ray diffraction (XRD). Crystalinity and surface bonding groups of carbon are investigated through X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy.

• 한국응용과학기술학회지
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• 제7권2호
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• pp.63-69
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• 1990

(2,3-Dibromopropyl) phenyl lauroyl phosphate[DPPL] was synthesized by adding lauric acid to (2,3-dibromopropyl)chloro phenyl phosphate [DPP]. which prepared from phenyl phosphoric acid dichloride with 2,3-dibromo propyl alcohol. Flame retardants of DPPF and DPPLF were prepared respectively. DPPF was a water soluble flame retardant, and DPPLF was o/w type emulsion flame retardant. After flame retardant treating two kinds of flame retardants to the various synthetic fabrics respectively. the flame retardancy and tear strength were measured. As the results of the measurement. DPPF had only name retardancy, but DPPLF had both of flame retardancy and softness.

• 한국연소학회지
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• 제11권1호
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• pp.11-18
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• 2006

In this work, $TiO_2$ nanoparticles were synthesized using $N_2-diluted$ and Oxygen-enriched coflow hydrogen diffusion flames. The effect of flame temperature on the characteristics of the formed $TiO_2$ nanoparticles was investigated. The measured maximum centerline temperature of the flame ranged from 2,103 K for oxygen-enriched flame to 1,339 K for $N_2-diluted$ flame. The visible flame length and the height of the main reaction zone were characterized by direct photographs. The characteristics of synthesized $TiO_2$ nanoparticles were analyzed by SEM and TEM images. From these images, it was evident that the formed nanoparticles were divided into two sorts. In the higher temperature region, over the 1,700 K, $TiO_2$ nanoparticles having spherical shapes with diameters about 60 nm were synthesized. In the lower temperature region, below the 1,600 K, the diameters of formed nanoparticles having unclear boundaries were ranged from 35 - 50 nm.

• 공업화학
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• 제3권4호
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• pp.670-677
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• 1992

2, 3-Dibromopropyl alcohol과 chlorophenyl phosphate로 부터 (2, 3-dibromopropyl)phenyl phosphate[DPP]를 합성하고, 또한 DPP에 n-octadecyl chloride를 가하여 (2,3-dibromopropyl)phenyl octadecyl phosphate[DPOP]를 합성하였다. DPP와 DPOP에 각각 유화제를 블렌딩시켜 난연제 DPPF와 DPOPF를 제조하였는데, 모두 o/w(oil in water)유화형 난연제였다. 이 2종류의 난연제를 각종 합성직물에 처리하여 난연성과 인열강도를 측정한 결과 DPPF는 난연성만이, 그리고 DPOPF는 난연성과 유연성 모두 양호하였다.

• 대한기계학회논문집B
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• 제30권7호
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• pp.692-699
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• 2006

In this work, $TiO_2$ nanoparticles were synthesized using $N_2-diluted$ and Oxygen-enriched co-flow hydrogen diffusion flames. The effect of flame temperature on the crystalline structure of the formed $TiO_2$ nanoparticles was investigated. The measured maximum centerline temperature of the flame ranged from 2,103k for oxygen-enriched flame to 1,339K for $N_2-diluted$ flame. The visible flame length and the height of the main reaction zone were characterized by direct photographs. The crystalline structures of $TiO_2$ nanoparticles were analyzed by XRD. From the XRD analysis, it was evident that the crystalline structures of the formed nanoparticles were divided into two sorts. In the higher temperature region, over the 1,700K, the fraction of formed $TiO_2$ nanoparticles having anatase-phase crystalline structure increased with increasing the flame temperature. On the contrary, in the lower temperature region, below the 1,600K, the fraction of anatase-phase nanoparticles increased with decreasing the flame temperature.

• 대한기계학회논문집B
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• 제28권2호
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• pp.215-222
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• 2004

Synthesis of multi-walled carbon nanotubes on a nickel-nitrate-deposited substrate using an ethylene fueled inverse diffusion flame was illustrated. The deposition of nickel-nitrate particles on substrates was used for the smaller-diameter nanotubes than those formed in our previous studies. Also the effect of temperature variations on the size of formed nanotubes was investigated. The diameters of formed multi-walled carbon nanotubes were ranging from 15 to 100 nm in the several radial locations. In case of using a nickel-nitrate-deposited substrate, the smaller-diameter carbon nanotubes were synthesized than those in case of using the substrate with melted nickel-nitrate. In the formation region of carbon nanotubes, the diameter of formed nanotubes was tend to be decrease as the radial distance form the flame center was increased, that is the decreased substrate temperature.