• 제목/요약/키워드: Heavy ion

검색결과 597건 처리시간 0.024초

Research Activities at National Institute of Radiological Sciences in Development of Radiological Apparatus

  • Endo, Masahiro
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.3-5
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    • 2002
  • This paper describes research activities at National Institute of Radiological Sciences (NIRS), Japan in development of radiological apparatus, which cover 4-dimensinal (4D) CT, next-generation PET and several progresses in heavy-ion irradiation system at HIMAC (Heavy Ion Medical Accelerator in Chiba).

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수용액 중에서 Polyamine계 유기응집제를 이용한 중금속 이온의 흡착 - 키토산의 분자량과 탈아세틸화도 - (An Investigation for the Adsorption of Heavy Metal Ions by Polyamine Organic Adsorbent from the Aqueous Solution - The Influence of Molecular Weight and Degree of Deacetylation of Chitosan -)

  • 박영미;전동원
    • 한국의류산업학회지
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    • 제8권4호
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    • pp.458-464
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    • 2006
  • The adsorption ability of heavy metal ions from the aqueous solution by chitosan, which it is well known natural biopolymer, has been investigated. The fundamental study in this research is focusing on the physicochemical adsorption utilizing the chitosan as a organic chelating adsorbent, adsorb especially heavy metal ions from the waste liquid solution. The adsorption ability of the chitosan between metal ions, having different characteristics with Mw of 188,600, 297,200, and 504,200 g/mol and degree of deacetylation (DD) of 86.92% and 100% were investigated targeting on the $Ni^{2+}$, $Co^{2+}$, $Zn^{2+}$, and $Pb^{2+}$ ions, respectively. The uptake of heavy metal ions with chitosan was performed by atomic absorption flame emission spectrophotometer (AAS) as conducted residual metal ions. It was found that chitosan has an strong adsorption capacity for some metals under certain conditions. Chitosan, which have 100% degree of deacetylation showed high adsorption recovery ratio and have an affinity for all kinds of heavy metals. In contrast, the molecular weight of chitosan was not completely affected on metal ion adsorption.

다량의 붕소원소를 함유하는 식물의 중금속 이온 교환반응 (Heavy Metal Son Exchange Reaction in Boron-Rich Containing Plants)

  • 배계선;성대동
    • 한국환경과학회지
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    • 제5권6호
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    • pp.757-762
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    • 1996
  • The removal effectiveness of various heavy metal ions in boron-rich containing plants has been studied by means of spectroscopic and pH methods. Treatment of the boron-rich containing sample which was collected from cherry and root of cabbage to heavy metal ions is resulted in that an excellent removal effect shows in the case of large ionic size of heavy metal. Stability constants are depended on the variation of pH.

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중이온 빔조사 담배(Nicotiana plumbaginifolia) 식물체의 생장과 DNA 변이 (Growth and DNA Alteration of Heavy-ion Beam Irradiated Tobacco(Nicotiana plumbaginifolia) Plant)

  • 류재일;김민수;;이효연;양덕춘;배창휴
    • 한국자원식물학회지
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    • 제18권1호
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    • pp.169-178
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    • 2005
  • 중이온빔$(^{20}Ne)$을 담배 식물체에 조사(irradiation)하여 식물체의 생장과 DNA의 변이에 미치는 영향을 검토하였다. 발아율과 초장은 조사선 량이 증가함에 따라 감소하였다. 반면 $50Gy\~10Gy$의 저선량에서 추대와 개화가 촉진되어 발육은 오히려 촉진되었다. 총 100개의 primer를 이용하여 RAPD분석한 결과, 59개의 primer에서 총 336개의 DNA단편이 증폭되었고, 1개의 primer에서 중이온빔 조사처리구에서만 출현하는 DNA단편이 나타났다. AFLP분석 결과, 개체 특이적인 DNA단편은 나타난 반면 중이온빔 처리구 특이적인 DNA 단편은 관찰되지 않았다.

컬럼반응조 내 충진된 다공성 zeolite-slag 세라믹에 의한 산성광산배수의 처리기작에 대한 미세분석 연구 (A Microscopic Study on Treatment Mechanism of Acid Mine Drainage by Porous Zeolite-slag Ceramics Packed in a Column Reactor System)

  • 임수빈
    • 한국수처리학회지
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    • 제26권6호
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    • pp.13-26
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    • 2018
  • This research was conducted to elucidate the removal mechanism of heavy metals and sulfate ion from acid mine drainage(AMD) by porous zeolite-slag ceramics (ZS ceramics) packed in a column reactor system. The average removal efficiencies of heavy metals and sulfate ion from AMD by the 1:3(Z:S) porous ZS ceramics in the column reactor under the HRT condition of 24 hours were Al 97.5%, As 98.8%, Cd 86.1%, Cu 96.2%, Fe 99.7%, Mn 64.1%, Pb 97.2%, Zn 66.7%, and $SO_4{^{2-}}$ 76.0% during 121 days of operation time. The XRD analysis showed that the ferric iron from AMD could be removed by adsorption and/or ion-exchange on the porous ZS ceramics. In addition it was known that Al, As, Cu, Mn, and Zn could adsorb or coprecipitate on the surface of Fe precipitates such as schwertmannite, ferrihydrite, or goethite. The EDS analysis revealed that Al, Fe, and Mn, which were of relatively high concentration in the AMD, would be adsorbed and/or ion-exchanged on the porous ZS ceramics and also exhibited that Al, Cu, Fe, Mn, and Zn could be precipitated as the form of metal hydroxide or sulfate and adsorbed or coprecipitated on the surface of Fe precipitates. The microscopic results on the porous ZS ceramics and precipitated sludge in a column reactor system suggested that the heavy metals and sulfate ion from AMD would be eliminated by the multiple mechanisms of coprecipitation, adsorption, ion-exchange as well as precipitation.

Design of an Air-Core HTS quadruple triplet for a heavy ion accelerator

  • Zhang, Zhan;Wei, Shaoqing;Lee, Sangjin
    • 한국초전도ㆍ저온공학회논문지
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    • 제18권4호
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    • pp.35-39
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    • 2016
  • In recent years, high-temperature superconductor (HTS) Quadruple Triplets are being developed for heavy ion accelerators, because the HTS magnets are suitable to withstand radiation and high heat loads in the hot cell of accelerators. Generally, an iron yoke, which costs a mass of material, was employed to enhance the magnetic field when a quadrupole magnet was designed. The type of the magnet is called iron-dominated magnet, because the total magnetic field was mainly induced by the iron. However, in the HTS superconductor iron-dominated magnets, the coil-induced field also can have a certain proportion. Therefore, the air-core HTS quadrupole magnets can be considered instead of the iron-core HTS quadrupole magnet to be employed to save the iron material. This study presents the design of an air-core HTS quadruple triplet which consists three by air-core HTS quadruple magnet and compare the design result with that of an iron-core HTS quadruple triplet. First, the characteristics of an air-core HTS quadrupole magnet were analyzed to select the magnet system for the magnetic field uniformity impairment. Then, the field uniformity was improved(< 0.1%) exactly using evolution strategy (ES) method for each iron-core HTS quadrupole magnet and the air-core HTS quadruple triplet was established. Finally, the designed air-core triplet was compared with the iron-core HTS quadruple triplet, and the results of beam trajectories were presented with both the HTS quadruple triplet systems to show that the air-core triplet can be employed instead of the iron-core HTS triplet. The design of the air-core quadruple triplet was suggested for a heavy ion accelerator.

The Noise Power Spectrum in Heavy Ion CT Based on Measurement of Residual Range Distribution

  • Yasuda, Naruomi;Abe, Shinji;Nishimura, Katsuyuki;Tomita, Tetsuya;Sato, Hitoshi;Muraishi, Hiroshi;Kanzaki, Takayuki;Inada, Tetsuo;Fujisaki, Tatsuya
    • 한국의학물리학회:학술대회논문집
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    • 한국의학물리학회 2002년도 Proceedings
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    • pp.228-230
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    • 2002
  • The relative electron density resolution was discussed by the noise power spectrum (NPS) in the heavy ion CT image. The heavy ion beam $\^$12/C accelerated up to 400MeV/u by RIMAC was used in this study. The two-dimensional (2-D) NPS in the CT image was obtained from the one-dimensional (1-D) NPS of the measured residual range distribution of water phantom for single projection, and the noise variance in the CT image was calculated from 2-D NPS. The technique used in the reconstruction was the filtered back-projection method with Shepp-Logan filter. The calculated value suggests the result of our previous works using the density resolution phantom, assuming that the relative electron density resolution is twice the standard deviation. Therefore, the estimation of the noise in CT images by 2-D NPS obtained the measured residual range distribution is the useful method.

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키틴에 의한 중금속 Cd(II), Pb(II)이온의 흡착 및 회수에 관한 연구 (Study on Adsorption and Recovery of Heavy Metal Ions, Cd(II) and Pb(II), by Chitin)

  • 김은경;조영구;권영두;박미아;김한수;박광하
    • 분석과학
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    • 제15권2호
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    • pp.163-171
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    • 2002
  • 수산가공 폐기물로 버려지는 게 껍질로부터 chitin을 추출하여 중금속 흡착제로 이용하였으며, 이 흡착제에 대해 Cd(II) 및 Pb(II) 이온의 흡착특성을 연구하였다. Chitin에 대한 Cd(II) 및 Pb(II) 이온의 흡착속도는 반응시간 2분경에 최대흡착량에 도달하였으며, 중금속 흡착에 미치는 pH의 영향은 두 이온 모두 pH 7.0>10.5>3.5순임을 알 수 있었다. Chitin에 대한 흡착률은 Cd(II)이온이 21${\sim}$99%이며, Pb(II)이온이 24${\sim}$95%이다. Cd(II)이온의 회수율은 22${\sim}$53%이고, Pb(II)이온의 회수율은 22${\sim}$73%로 나타났다. 이들 중금속 이온의 흡착양상은 Freundlich 흡착등온식에 비교적 잘 적용되었다.

유연탄 비산회로부터 합성한 제올라이트 4A에 의한 중금속 이온의 흡착 (Adsorption of Heavy Metal Ions by Synthesized Zeolite 4A using Bituminous Coal Fly Ash)

  • 김상호;연익준;김광렬
    • 환경위생공학
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    • 제14권3호
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    • pp.63-70
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    • 1999
  • A study on the zeolite synthesized of bituminous coal fly ash from power plant has been carried out to reuse industrial waste. The synthesized zeolite was proved to be 4A type by means of the X-ray diffraction analysis and the degree of crystallinity was found to be higher than 90%. Then the synthesized zeolite was used as an adsorbent to remove the heavy metal ions in the CU, Pb, and Cd containing wastewater and water. Also, adsorption characteristics and kinetics of synthesized zeolite in the each metal ion solutions were studied. In each ion solutions, the adsorbed amounts of Pb, Cd, and Cu to the unit weight of synthesized zeolite were 141.6, 118.8, and 131.4mg/g respectively when each metal ion concentration was 500mg/L solution. The adsorption kinetics was fitted well to the Freundlich isotherms. The value of l/n for Pb, Cd, and Cu and 0.27, 0.50, and 0.66, respectively. Those results showed that the synthesized zeolite could be used as an adsorbent to remove single heavy metal ions in the wastewater and water. The heats of adsorption, H values of Pb, Cd, and Cu were 4.87, 14.95, and 18.23kacl/mol by the Henry-van't Hoff equation.

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Harmonic analysis and field quality improvement of an HTS quadrupole magnet for a heavy ion accelerator

  • Zhang, Zhan;Wei, Shaoqing;Lee, Sangjin;Jo, Hyun Chul;Kim, Do Gyun;Kim, Jongwon
    • 한국초전도ㆍ저온공학회논문지
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    • 제18권2호
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    • pp.21-24
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    • 2016
  • In recent years, the iron-dominated high-temperature superconductor (HTS) quadrupole magnets are being developed for heavy ion accelerators. Field analyses for iron-dominated quadrupole magnets were based on the normal-conducting (NC) quadrupole magnet early in the development for accelerators. Some conclusions are still in use today. However, the magnetic field of iron-dominated HTS quadrupole magnets cannot fully follow these conclusions. This study established an HTS quadrupole magnet model and an NC quadrupole magnet model, respectively. The harmonic characteristics of two magnets were analyzed and compared. According to the comparison, the conventional iron-dominated quadrupole magnets can be designed for maximum field gradient; the HTS quadrupole magnet, however, should be considered with varying field gradient. Finally, the HTS quadrupole magnet was designed for the changing field gradient. The field quality of the design was improved comparing with the result of the previous study. The new design for the HTS quadrupole magnet has been suggested.