• 제목/요약/키워드: Electron irradiation

검색결과 1,014건 처리시간 0.028초

Quality Evaluation of Sliced and Pizza Cheeses Treated by Gamma and Electron Beam Irradiation

  • Kim, Hyun-Joo;Ham, Jun-Sang;Kim, Kee-Hyuk;Ha, Ji-Hyoung;Ha, Sang-Do;Jo, Cheo-Run
    • Asian-Australasian Journal of Animal Sciences
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    • 제23권8호
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    • pp.1112-1117
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    • 2010
  • This study was conducted to evaluate and compare the quality changes of commercial sliced and pizza cheeses processed by gamma and electron beam irradiation. The $L^*$-value of sliced and pizza cheeses decreased and the $a^*$-value decreased only in pizza cheese by both irradiation sources. There was no change in pH. There was no difference in 2-thiobarbituric acid reactive substances (TBARS) value between non-irradiated and irradiated samples at a dose of 3 kGy or less (p<0.05). However, both irradiation sources resulted in increased TBARS value in sliced and pizza cheeses at 5 kGy. Sensory evaluation revealed that irradiation influenced odor, taste and overall acceptability of both cheeses and may cause the limitation of consumers' acceptance for irradiated cheese products. Results indicate that both gamma and electron beam irradiations with less than 3 kGy may not influence significantly the physicochemical quality of sliced and pizza cheeses. However, to meet a market requirement, a method to overcome the sensory deterioration of cheeses should be developed and applied.

전자빔 조사에 따른 GZO/TiO2 박막의 특성 변화 (Effect of Electron Irradiation on the Properties of GZO/TiO2 Thin Films)

  • 김승홍;김선경;김소영;허성보;최동혁;손동일;김대일
    • 열처리공학회지
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    • 제26권6호
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    • pp.288-292
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    • 2013
  • We have considered the influence of electron irradiation energy of 300, 600 and 900 eV on the stuctural, electrical and optical properties of GZO/$TiO_2$ thin films prepared with RF magentron sputtering. The optical transmittance and electrical resistivity of the films were dependent on the electron's irradiation energy. The electron irradiated GZO/$TiO_2$ films at 900 eV are grown as a hexagonal wurtzite phase and the resistivity is decreased with electron irradiation energy. The GZO/$TiO_2$ films irradiated at 900 eV shows the lowest resistivity of $4.3{\times}10^{-3}{\Omega}cm$. The optical transmittance in a visible wave length region also increased with the electron irradiation energy. The film that electron irradiated at 900 eV shows 82% of optical transmittance and higher work function of 5.18 eV in this study.

전자빔 조사에 의한 방향성 전기강판의 철손 감소를 위한 소형 전자빔 조사장치 설계 (Design of a miniature electron beam irradiation apparatus for domain refining grain oriented electrical steel with electron beams)

  • 조경재
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2000년도 전력전자학술대회 논문집
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    • pp.18-21
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    • 2000
  • A nonconstact technique for reducing the core loss of a grain oriented silicon steel has been developed by the use of mechanical scribing Q-switched laser plasma jet or electron beam irradiation. Among these methods electron beam irradiation has advantages of domain refining without any deformation or damage of insulating film on the surface of a grain criented Si-Fe. Over the past years this processing was performed in vaccum of 10-4 Torr or below causing the problem of high cost and difficulty of continuous works. In this paper a miniature electron permeable window through which electron beam energy 4-80keV and average current 0.1-2mA. were obtained for electron beam irradiating on air was designed and manufactured.

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Synthesis of Nickel Nanoparticles using Electron Beam Irradiation

  • Lee, Seung Jun;Kim, Hyun Bin;Oh, Seung Hwan;Kang, Phil Hyun
    • Journal of Magnetics
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    • 제20권3호
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    • pp.241-245
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    • 2015
  • A study on the preparation of nickel oxide nanoparticles using electron beam irradiation is described. Nickel nanoparticles were synthesized with nickel chloride hexahydrate as a metal precursor and different sodium hydroxide concentrations using electron beam irradiation. The effects of sodium hydroxide concentration and electron beam absorbed doses were investigated. The samples were synthesized at different sodium hydroxide concentrations and with absorbed doses of 100 to 500 kGy at room temperature. Synthesized nanoparticles were characterized by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) and a vibrating sample magnetometer (VSM). The nanoparticle morphologies seemed to be non-spherical and aggregated. The 1:1 molar ratio of nickel chloride hexahydrate and sodium hydroxide showed a higher purity and saturation magnetization value of 13.0 emu/g. The electron beam absorbed dose was increased with increasing nickel nanoparticle nucleation.

방사선조사가 하악과두에 미치는 영향에 관한 전자현미경적 연구 (ELECTRON MICROSCOPIC STUDY OF THE IRRADIATION EFFECT ON THE RAT MANDIBULAR CONDYLE)

  • 박명선;박태원
    • 치과방사선
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    • 제26권2호
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    • pp.45-63
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    • 1996
  • In attempt to determine radiation effect on the mandibular condyle of the growing rat, 27 white female rats (Sprague-Dawley) were divided into 3 groups and irradiated respectively 5Gy, 10Gy, 20Gy using MK Cell Irradiator. Mandibular condyles from rats on the day of 1, 7, 14 after the irradiation day were obtained, sectioned sagittally and examined by light microscopy, and thereafter middle portion through anteroposterior direction on the sagittal plane was selected to examine the ultrastructural change by transmission electron microscopy. The obtained results are followings. 1. In the proliferative zone some cells showed little organelles in case of 5Gy irradiation, in addition the number of degenerative cells increased and in case of 10Gy irradiation, and in case of 20 Gy irradiation total number of cells decreased. 2. In the hypertrophic zone, narrowing of width and partial disorder in hypertrophic process were noted in case of 5 Gy irradiation, and more prominent narrowing of width and more irregular disorder in hypertrophic process in case of both 10Gy and 20Gy irradiation. 3. In the upper hypertrophic zone some chondrocytes seemed to be dying and the polarity of nuclei could not be seen, if any. 4. The periodic observation showed the severest change at day 7 and the signs of recovery at day 14 after irradiation.

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전자빔 표면 조사에 따른 GZO 박막의 물성과 가스센서 응용 연구 (Effect of Electron Irradiation on the Properties of GZO Thin Film and its Gas Sensor Application)

  • 김대일
    • 열처리공학회지
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    • 제24권3호
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    • pp.140-143
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    • 2011
  • In this work, Ga doped ZnO (GZO) films were prepared by radio frequency (RF) magnetron sputtering without intentional substrate heating on glass substrate and then the effect of the intense electron irradiation on structural and electrical properties and the NOx gas sensitivity were investigated. Although as deposited GZO films showed a diffraction peak for ZnO (002) in the XRD pattern, GZO films that electron irradiated at electron energy of 900 eV showed the higher intense diffraction peaks than that of the as deposited GZO films. The electrical property of the films are also influenced with electron's energy. As deposited GZO films showed the three times higher resistivity than that of the films irradiated at 900 eV In addition, the sensitivity for NOx gas is also increased with electron irradiation energy and the film sensor showed the proportionally increased gas sensitivity with NOx concentration. This approach is promising in gaining improvement in the performance of thin film gas sensors used for the detection of hazard gas phase.

Effects of Electron Beam Irradiation on Tribological and Physico-chemical Properties of Polyoxymethylene (POM-C) copolymer

  • ;;;;김민석
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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    • pp.153-153
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    • 2016
  • Polyoxymethylene copolymer (POM-C) is an attractive and widely used engineering thermoplastic across many industrial sectors owing to outstanding physical, mechanical, self-lubricating and chemical properties. In this research work, the POM-C blocks were irradiated with 1 MeV electron beam energy in five doses (100, 200, 300, 500 and 700 KGy) in vacuum condition at room temperature. The tribological and physico-chemical properties of electron beam irradiated POM-C blocks have been analyzed using Pin on disk tribometer, Raman spectroscopy, SEM-EDS, Optical microscopy, 3D Nano surface profiler system and Contact angle analyzer. Electron beam irradiation at a dose of 100 kGy resulted in a decrease of the friction coefficient and wear loss of POM-C block due to well suited cross-linking, carbonization, free radicals formation and energetic electrons-atoms collisions (physical interaction). It also shows lowest surface roughness and highest water contact angle among all unirradiated and irradiated POM-C blocks. The irradiation doses at 200, 300, 500 and 700 kGy resulted in increase of the friction coefficient as compared to unirradiated POM-C block due to severe chain scission, chemical and physical structural degradation. The electron beam irradiation transferred the wear of unirradiated POM-C block from the abrasive wear, adhesive wear and scraping to mild scraping for the 1 MeV, 100 kGy irradiated POM-C block which is concluded from SEM-EDS and Optical microscopic observations. The degree of improvement for tribological attribute relies on the electron beam irradiation condition (energy and dose rate).

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전자빔 조사 에너지에 따른 In2O3 박막의 특성 변화 (Effect of Electron Irradiation Energy on the Properties of In2O3 Thin Films)

  • 허성보;천주용;이영진;이학민;김대일
    • 열처리공학회지
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    • 제25권3호
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    • pp.134-137
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    • 2012
  • We have considered the effect of electron irradiation energy of 300, 600 and 900 eV on structural, electrical and optical properties of $In_2O_3$ films prepared with RF magnetron sputtering. In this study, the thin film crystallization, optical transmittance and sheet resistance are dependent on the electron's irradiation energy. The electron irradiated $In_2O_3$ films at 900 eV are grown as a hexagonal wurtzite phase. The sheet resistance decreases with a increase in electron irradiation energy and $In_2O_3$ film irradiated at 900 eV shows the lowest sheet resistance of $110{\Omega}/{\Box}$. The optical transmittance of $In_2O_3$ films in a visible wave length region also depends on the electron irradiation energy. The film that at 900 eV shows the higher figure of merit than another films prepared in this study.

PC 기판위에 증착된 SiO2/GZO박막의 전자빔 조사에너지에 따른 특성 변화 (Effect of Electron Irradiation Energy on the Properties of GZO/SiO2 Thin Films on Polycarbonate)

  • 허성보;박민재;정우창;김대일;차병철
    • 한국표면공학회지
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    • 제47권6호
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    • pp.341-346
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    • 2014
  • Ga-doped ZnO (GZO) single layer and $SiO_2/GZO$ bi-layered films were deposited on Polycarbonate(PC) substrate by radio frequency magnetron sputtering. Influence of the structural, electrical, and optical properties of the films was considered. We have considered the influence of electron irradiation energy of 450 and 900 eV on the stuctural, electrical and optical properties of $SiO_2/GZO$ thin films. The optical transmittance in a visible wave length region increased with the electron irradiation energy. The electrical resistivity of the films were dependent on the electron's irradiation energy. The $SiO_2/GZO$ films irradiated at 900 eV were showen the lowest resistivity of $7.8{\times}10^{-3}{\Omega}cm$. The film which was irradiated by electron at 900 eV shows 84.3% optical transmittance and also shows lower than contact angle of $58^{\circ}$ in this study.

Differential Modulation of Volatile Constituents in Artemisia princeps and Artemisia argyi Plants after Gamma Ray or Electron Beam Irradiation

  • Kim, Ji Hong;Cho, Eun Ju;Lee, Min Hee;Kim, Ji Eun;Chung, Byung Yeoup;Kim, Tae Hoon;Kim, Jin-Hong
    • 방사선산업학회지
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    • 제6권1호
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    • pp.17-21
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    • 2012
  • The effects of gamma ray or electron beam irradiation on herbaceous medicinal plants were investigated in terms of the composition of volatile constituents using the aerial parts or leaves of Artemisia princeps Pamp. cv. Ganghwayakssuk and Artemisia argyi cvs. Namhaeyakssuk and Hwanghaessuk. The composition of volatile constituents in leaves was clearly distinguishable among the three Artemisia cultivars. However, the relative proportions of the major volatile constituents such as 1,8-cineole, ${\alpha}$-pinene, camphene, santolina triene, and artemesia triene, were similarly changed in two or three cultivars by gamma ray or electron beam irradiation. In particular, the proportion of 1,8-cineole was increased up to 1.29- to 1.71-fold in the three cultivars after irradiation with gamma ray. These results suggest that gamma ray or electron beam irradiation can be applied to modulate the composition of volatile constituents in the leaves of Artemisia plants.