• Title/Summary/Keyword: Nano 입자

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Tensile and Compressive Strength Characteristics of Aluminized Paraffin Wax Fuel for Various Particle Size and Contents (파라핀/알루미늄 연료의 알루미늄 입자크기 및 함유비 변화에 따른 인장 및 압축강도 특성 연구)

  • Ryu, Sunghoon;Han, Seongjoo;Kim, Jinkon;Moon, Heejang;Kim, Junhyung;Ko, Seung Won
    • Journal of the Korean Society of Propulsion Engineers
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    • v.20 no.5
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    • pp.70-76
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    • 2016
  • Tensile and compressive strength tests were conducted to investigate the mechanical characteristics of aluminized paraffin wax fuel for hybrid gas generator applications. Mixtures of 0 wt%, 10 wt% and 30 wt% nano aluminum paraffin coupons as well as 5 wt%, 10 wt% and 15 wt% micro aluminum paraffin coupons were used. The average particle size of 100nm and of $8{\mu}m$ mixed each with microcrystalline paraffin wax(Sasol 0907) were chosen for the base specimens where the tensile strength test followed the ASTM-D638 specimen standard while the compressive strength test followed the ASTM D575-91. It was found that nano based specimens increased both the tensile and compressive strength enhancing the mechanical behavior of paraffin wax whereas the micro based specimens gave still less influential effect.

Characteristics and Release Behaviors of Aromatic Poly(vinyl acetate) Nanoparticles Prepared by Emulsification-Diffusion Technique (유화-확산법에 의해 얻어진 폴리(비닐 아세테이트) 나노 방향 입자의 특성 및 방출 거동)

  • Sohn, Sung-Ok;Lee, So-Min;Kim, Yun-Mi;Ghim, Han-Do
    • Polymer(Korea)
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    • v.31 no.3
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    • pp.177-183
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    • 2007
  • In this study, nano-sized poly(vinyl acetate) (PVAc) particles containing lavender oil as a core material were prepared by using emulsification-diffusion method. Effects of experimental parameters on the characteristics and the release behavior were examined with a field emission- scanning electron microscope, an electrophoretic light scattering spectrophotometer, a visible spectrophotometer and a high performance liquid chromatography The resulting aromatic particles could be prepared in nano-sized globular shapes with the mean particle size of 224 nm by controlling the experimental conditions. From the evaluation of release properties of aromatic PVAc nanoparticles with or without PVA coating, it was found that the aromatic particles coated with PVA show more sustaining and stable release behaviors. Our research on aromatic PVAc nanoparticles could be applied for durable fragrant finishing for textiles, leather products and so on.

Structure Determination of Nano-crystalline, $BaTiO_3$, using Precession Electron Diffraction (세차전자회절을 이용한 $BaTiO_3$ 나노 결정의 구조분석)

  • Song, Kyung;Kim, Youn-Joong;Kwon, Ki-Hyun;Kim, Jin-Gyu;Moon, Sun-Min;Cho, Nam-Hee
    • Applied Microscopy
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    • v.39 no.4
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    • pp.341-348
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    • 2009
  • The crystal structure of nano-crystalline, $BaTiO_3$, with the average particle size of 100 nm was investigated using electron diffraction techniques. We characterized the precession electron diffraction system and then carried out the structure determination using precession electron diffraction and conventional selected area electron diffraction. As a result, it was revealed that $BaTiO_3$ nano-crystalline exist as a mixture of tetragonal structure and cubic structure by precession electron diffraction technique. In addition, it could be turned out that $BaTiO_3$ nano-crystalline is a core-shell structure consisted of a tetragonal phased core and a cubic phased surface layer by theoretical calculation. The thickness of the cubic surface layer was approximately 8.5 nm and the lattice parameters of cubic and tetragonal phases were a=3.999${\AA}$ and a=3.999${\AA}$, c=4.022${\AA}$, respectively. Finally, it is expected that precession electron diffraction is more useful technique for structure determination of complicated nano-crystalline materials because of its higher spatial resolution and minimization of dynamical scattering effect.

A Study on Characteristics of Performance and Emission by CRDI Engine's Injection Strategy (커먼레일 디젤기관에서 분사전략에 따른 성능 및 배출가스에 관한 연구)

  • Eom, Dong-Seop;Ko, Dong-Kyun;Ra, Wan-Yong;Lee, Seang-Wock
    • Journal of ILASS-Korea
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    • v.16 no.3
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    • pp.134-139
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    • 2011
  • Recent research has focused on engine combustion technology as well as application of after-treatment in order to comply with emission regulation. However, it is much more efficient way to control emissions from engine itself and furthermore research on engine control will provide the direction of after-treatment technology in future. Furthermore, emission standard regulation for passenger diesel vehicles has been stringent compared to others and nano-particles will be included in EURO6 regulation in Europe and similar emission standard will be introduced in Korea. A 3.0 liter high speed diesel engine equipped with by CRDI system of 160MPa injection pressure, and an intake/exhaust system of V type 6 cylinder turbo-intercooler was applied. The injection duration and injection quantity, pilot injection types which are related to CRDI and air/fuel ratio control applied by EVGT were changed simultaneously. Standard experiment procedure constituted dilution apparatus and CPC system to collect nano-particles and these test results were compared with regulated materials of CO, HC, NOx and investigated their relations and characteristics of nano-particles.

Experimental Evaluation of EGR and Fuel Injection Pressure on Combustion, Size-resolved Nano-particle and NOx Emissions Characteristics in an Advanced Light-duty Diesel Engine (승용 디젤 엔진의 배기가스재순환 및 연료 분사 압력 제어전략에 따른 연소, 입자상 물질 및 질소 산화물 배출 특성에 관한 연구)

  • You, Jung Been;Ko, Ahyun;Jang, Wonwook;Baek, Sungha;Jin, Dong Young;Myung, Cha-Lee;Park, Simsoo;Han, Jung Won
    • Transactions of the Korean Society of Automotive Engineers
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    • v.22 no.7
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    • pp.8-15
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    • 2014
  • In order to satisfy stringent future emission regulation in diesel engines, systematic approaches to mitigate the harmful exhaust emissions were developed, such as engine hardware, fuel injection equipment, engine control, and after-treatment system. In this study, to improve the nano-particle and NOx emissions from a state-of-the-arts diesel engine, effect of various EGR and fuel injection pressure with combustion analysis were evaluated. Size-resolved nano-particle and NOx emissions showed trade-off characteristics with various EGR rate and increment of fuel injection pressure.