• 제목/요약/키워드: Ultrasonic Irradiation

검색결과 163건 처리시간 0.027초

PVA 함유 수용액으로부터 초음파 조사에 의한 CdSe 중공 입자의 합성 (Synthesis of hollow Sphere CdSe in PVA Aqueous Solution by Using Ultrasonic Irradiation)

  • 박명국;이윤복;김용진;김인배;김양도
    • 한국세라믹학회지
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    • 제44권2호
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    • pp.84-88
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    • 2007
  • CdSe hollow spheres with the diameter of about 30-50 nm were synthesized after ultrasonic irradiation in the presence of $Cd(NO_3)_2,\;Na_2SeSO_3$, and polyvinylalcohol(PVA). The characteristics of CdSe hollow spheres were analyzed using X-ray diffraction(XRD), transmission electron microscopy(TEM), UV-vis measurement and PL spectrometer. The characteristics of solvent as water and water-1-propanol mixture in the system played important roles on the controlled synthesis of hollow sphere. Based on the observation of morphological difference of CdSe, the possible mechanism of CdSe hollow sphere formation will be discussed.

화학적 방법에 의한 CdSe 나노입자의 제조 및 특성 (Preparation and characterization of CdSe nanoparticles through a chemical route)

  • 성명석;이윤복;김형국;김양도
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2005년도 춘계학술대회
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    • pp.164-167
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    • 2005
  • Diethnao lamine(DEA)을 함유한 수용액을 ultrasonic irradiation에 의하여 CdSe 반도체 양자점을 제조하였고 제조된 양자점의 광학적 성질을 조사하였다. CdSe 양자점 제조시 카드뮴을 제공하는 물질로는 $CdCl_2{\cdot}2.5H_2O$를, 셀레늄을 제공하는 물질로는 Se powders를 $Na_2SO_3$ 수용액에서 $90^{\circ}C$, 1시간 reflux 한 $Na_2SeSO_3$를 사용하였다. 상온에서 고출력의 초음파 조사 (20kHz, $60Wcm^{-2}$)에 의한 CdSe반도체 양자점을 얻기 위하여 초음파 시간을 각각 변화시켰고 XRD, UV-Vis, PL, TEM, XPS론 사용하여 CdSe 나노 입자의 특성을 분석하였다. CdSe흡수스펙트럼을 분석한 결과 450-640nm범위에서 양자점 형성에 의한 엑시톤 흡수 봉우리가 관찰되었음을 확인할 수 있었다. 또한 초음파 조사시간을 5분, 15분, 30분으로 증가시킴에 따라 505nm, 525nm, 545nm로서 엑시톤의 흡수 파장이 장파장 쪽으로 이동함을 확인함으로써 초음파 조사시간에 따라 CdSe 양자점의 크기를 변화시킬 수 있음을 알 수 있었다.

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Synthesis of Polypropylene-Polystyrene Copolymer via Ultrasonic Irradiation-Initiated Polymerization of Styrene in Polypropylene Solution

  • Kim, Hyungsu;Kim, Jihye;Kim, Miwha;Seyoung Oh;Lee, Jaewook
    • Macromolecular Research
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    • 제9권3호
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    • pp.150-156
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    • 2001
  • Polystyrenes(PS) were grafted onto polypropylene(PP) in the PP solution by ultrasonic irradiation-initiated polymerization of styrene. The resulting products consisted of mixtures of homopolymers and PP-PS copolymer because of the homopolymerization of styrene itself and copolymerization with PP. The dependency of the designated polymerization on sonication times was investigated to monitor the evolution lion of the copolymerization. Formation of the PP-PS copolymer was confirmed by FTIR analysis of the reaction products after a proper separation procedure of free PS and PP-PS copolymer. It was found that the tendency for the formation of PP-PS copolymer was closely related with the phase behavior of the PP/styrene mixture which was also influenced by sonication time. In order to verify the effectiveness of the PP-PS copolymer as a compatibilizer for PP/PS blend, melt mixing of PP/PS/PP-PS was performed in a batch mixer. During the mixing, the average torque was higher for the blend containing PP-PS copolymer influencing compatibilization. In accordance with the results from FRIR analysis and torque measurement, the PS domain size remarkably decreased in the PP/PS/PP-PS blend.

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방향족 아민 화합물과 풀러렌 산화물의 [C70(O)n](n≥1)의 초음파 화학 반응 (Sonochemical Reaction of Fullerene Oxides, [C70(O)n](n≥1) with Aromatic Amines)

  • 고원배;박병은;이영민
    • Elastomers and Composites
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    • 제43권1호
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    • pp.31-38
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    • 2008
  • [ $FeCl_3$ ]를 첨가한 초음파 조건에서 4-nitroaniline, 3-nitroaniline, and 4-isopropylaniline등의 방향족 아민 화합물과 풀러렌 산화물$[C_{70}(O)_n](n\geq1)$을 반응시켰다. 이 반응은 방향족 아민 화합물을 사용한 풀러렌 산화물 쪼개짐 반응이다. MALDI-TOF-MS and UV-vis spectra를 사용하여 생성된 화합물이 아민화 풀러렌 유도체임을 확인하였다.

선박 슬러지유 환경에서의 초음파진동자 선단의 침식손상(1) -유온도의 변화에 대해서- (Erosion Damage of Ultrasonic Vibrator Tip in Marine Sludge Oil Environment -as for oil temp. change-)

  • 이진열;정지선;하만식;한원희
    • 해양환경안전학회지
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    • 제7권2호
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    • pp.1-11
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    • 2001
  • Many investments and works being continued to preserve green ocean in each countries of the world. Especial1y, the researches on the prevention of marine oil pollution being strengthened. It is not easy to disclose sludge oils that were produced necessarily in the ships operation, so that they are transferred to shore treating facility after collected inside the ship's sludge tank mostly. However, this shore transferring method is not only costly and time consuming but also entails risk of oil pollution. In this regard, it will be the best way to manage the sludge oils inside ship itself. The purpose of this study is to device an ultrasonic breaking systems which recycle the sludge oil from ships into usable oil to be burnt. In this paper, the first place, matrix structures of sludge fuel oil(SFO) and sludge lubricating oil(SLO) with the irradiation time for ultrasonic vibrator were interpreted. And, erosion damage for vibrator horn tip which is one of important part of ultrasonic breaking systems was examined under such an environment of the sludge oils. The material for horn tip is being made of SS41 steel and its erosion phase was investigated with variation of the vibration amplitude of 50${\mu}{\textrm}{m}$ and 24${\mu}{\textrm}{m}$ as well as the change of temperature in the oil environments. It is suggested that the experimental results can be helpful to the development of sludge oil disposing systems for the vessel.

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