• Title/Summary/Keyword: Electron-beam irradiation

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Effects of Electron Beam Radiation on the Microflora and Sensory Characteristics of Pork Loin (전자선 조사에 의한 국내산 신선 돈육의 미생물학적 및 관능적 특성 변화)

  • Min, Joong-Seok;Kim, Il-Seok;Lee, Moo-Ha
    • Korean Journal of Food Science and Technology
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    • v.31 no.3
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    • pp.746-750
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    • 1999
  • The effects of electron-beam irradiation on the microbial and sensory qualities of pork loins were studied. The pork loins were aerobically packed in polyethylene films and exposed to absorbed doses of electron-beam at 0, 0.5, 1 and 2 kGy in ambient temperature. All samples were stored at $4{\pm}1^{\circ}C$. As an irradiation dose increased, decontaminating effects increased in terms of total microbial count, lactic acid bacteria and psychrotrophs during storage. All difference degrees in the triangle test were very low levels. In the descriptive analysis, Low dose irradiation did not affect aroma, off-flavor and acceptability in fresh and cooked meats.

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Morphology and Rheological Property of PLA/PCL Blend Compatibilized by Electron Beam Irradiation (전자선 조사에 의해 상용화된 PLA/PCL 블렌드의 모폴로지 및 유변학적 성질)

  • Shin, Boo-Young;Cho, Baek-Hee;Hong, Ki-Heon;Kim, Bong-Shik
    • Polymer(Korea)
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    • v.33 no.6
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    • pp.588-595
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    • 2009
  • The aim of this study was to increase compatibility of immiscible PLA/PCL blend by using electron beam irradiation in the presence of glycidyl methacrylate (GMA). The blends of PLA/PCL containing GMA were irradiated at doses of 10, 50 and 100 kGy and then the irradiated samples were characterized by observing morphology and rheological properties. Blends irradiated with 50 and 100 kGy showed greatly improved interfacial adhesion between two phases in the morphology. Complex viscosity of PLA/PCL(9/1) blend irradiated at dose of 100 kGy was about 100 times higher than that of pure PLA. We found that the compatibility of immiscible PLA/PCL could be improved by electron beam irradiation in the presence of GMA from the investigation of morphology and rheology.

The Effect of Electron Beam Irradiation for Volumn Resistivity in the Molding Compound for Power Semiconductor (전력용 반도체 몰딩재료의 체척고유저항에 미치는 전차선 조사의 영향)

  • Lee, Yong-Woo;Hong, Nung-Pyo;Park, Woo-Hyun;Ga, Chul-Hyun;Lee, Soo-Won;Hong, Jin-Woong
    • Proceedings of the KIEE Conference
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    • 1995.11a
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    • pp.370-372
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    • 1995
  • This paper mainly, describes the electrical characteristics caused by the change of structure in solid state of specimen by electron beam irradiation of high temperature-low expension type molding materials of power semiconductor element. The experiments on physical properties and electrical characteristics for the specimen irradiated electron beam are carried ont. For the investigation on physical properties, XRD analysis is used. And for the experiment of electrical characteristics, measurement of volumn resistivity is used.

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A study on the Si Solar cell's conversion efficiency by 80keV Small Electron-beam irradiation (80keV 소형 전자빔을 이용한 Si 태양전지의 변환 효율 특성에 관한 연구)

  • Yoon Jeong-Phil;Cho Kyung-Jae;Gang Byong-Bok;Cho Seong-Oh;Cha In-Su
    • Proceedings of the KIPE Conference
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    • 2002.11a
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    • pp.59-61
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    • 2002
  • This research investigates electron beam to specification energy to Module that was generalized and schematized difference of curved line after existing V-I efficiency characteristic curve and irradiation. And will analyze cause of Si crystal Solar cell's efficiency addition and subtraction by 80keV electron beam investigation.

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Application of Electron-Beam Irradiation Combined with Aging for Improvement of Microbiological and Physicochemical Quality of Beef Loin

  • Yim, Dong-Gyun;Jo, Cheorun;Kim, Hyun Cheol;Seo, Kang Seok;Nam, Ki-Chang
    • Food Science of Animal Resources
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    • v.36 no.2
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    • pp.215-222
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    • 2016
  • The combined effects of irradiation and aging temperature on the microbial and chemical quality of beef loin were investigated. The samples were vacuum-packaged, irradiated at 0 or 2 kGy using electron-beam (EB), and stored for 10 d at different aging temperatures (2, 14, or 25℃). The microbial growth, shear values, meat color, and nucleotide-related flavor compounds of the samples were analyzed. The irradiation effect on inactivation of foodborne pathogens was also investigated. The population of Listeria monocytogenes and Escherhia coli O157:H7 inoculated in beef samples decreased in proportion to the irradiation dose. Irradiation reduced the total aerobic bacteria (TAB) over the storage, but higher aging temperature increased the TBA. Thus TAB increased sharply in non-irradiated and high temperature-aged (14, 25℃) beef samples after 5 d. With increasing aging temperature and aging time, shear force values decreased. Lipid oxidation could be reduced by short aging time at low aging temperature. The color a* values of the irradiated beef were lower than those of the non-irradiated throughout the aging period. As aging period and temperature increased, IMP decreased and hypoxanthine increased. Considering microbial and physicochemical properties, irradiation can be used for raw beef to be aged at relatively high temperature to shorten aging time and cost.

Effect of Electron Beam Irradiation on Selected Vegetable Seeds and Plant-Pathogenic Microorganisms (전자선 조사의 채소 종자 및 식물병원성 미생물에 대한 영향)

  • Bae, Young-Min
    • Journal of Life Science
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    • v.23 no.12
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    • pp.1415-1419
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    • 2013
  • Electron beam (EB) irradiation was tested to determine the dose required to eradicate plant pathogens, such as Botrytis cinerea and Agrobacterium rhizogenes, from the infected seeds without affecting the germination rate of the irradiated vegetable seeds, including crown daisy, cucumber, hot pepper, green onion, leaf lettuce, and radish seeds. EB irradiation of 1.5 kGy and 2 kGy was sufficient to kill 100% of hairy root disease bacteria and gray mold conidia, respectively. EB irradiation showed no effect or minimal effect on the germination rate of the crown daisy, cucumber, green onion, and radish seeds. However, the germination rate of the hot pepper and leaf lettuce seeds was significantly reduced by using 2 kGy of EB irradiation. Difference in susceptibility to EB irradiation appears not to be related to the weight of each seed, but to the intrinsic characteristic of each plant. Conclusively, EB irradiation might be a useful way to decontaminate crown daisy, cucumber, green onion, and radish seeds.

Electron-Beam Mediated Rearrangement and Fragmentation of Bis(diphenylphosphino)alkane Derivatives in Gas Phase

  • Jeon, Yea-Sel;Choi, Jeong Chul;Jeong, Young-Sik;Hwang, Kwang-Jin
    • Rapid Communication in Photoscience
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    • v.2 no.1
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    • pp.31-33
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    • 2013
  • The irradiation of electron-beam onto bis-(diphenylphosphino)methane, ethane, propane and butane initiated phenyl-shift from a phosphine to another phosphine atom and subsequent fragmentation resulted in the formation of triphenylphosphine derivative as key intermediate. The mechanism of those processes is speculated.

Homogeneous Alignment Characteristics of Liquid Crystal Molecules on Solution-Derived Lanthanum Zinc Oxide Film with Ion-Beam Irradiation (이온빔 조사된 용액 공정 기반 LaZnO 박막 위 액정 분자의 수평 배향 특성)

  • Oh, Byeong-Yun
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.5
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    • pp.382-386
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    • 2019
  • The alignment characteristics of liquid crystal (LC) molecules on a solution-derived lanthanum zinc oxide (LZO) film under ion-beam irradiation were demonstrated. Using the solution process, an LZO film was fabricated on the glass substrate and cured at $100^{\circ}C$. Afterwards, ion-beam irradiation was performed following the LC alignment method. Using this film, an LC cell was fabricated and the characteristics of the LC alignment were verified. Cross polarizing microscopy and the crystal rotation method were used to investigate the alignment state of the LC molecules on the LZO films. Furthermore, field emission scanning electron microscopy and X-ray photoelectron spectroscopy were used to explore the effect of the ion-beam irradiation on the LZO film. Through these, it was confirmed that the ion-beam irradiation induced surface modification, which demonstrated anisotropic physical and chemical surface characteristics. Due to this, uniform LC alignment was achieved. Finally, the residual DC and anchoring energy of the LC cell based on the LZO films were measured using a capacitance-voltage curve.

Effects of electron beam irradiation on the superconducting properties of YBCO thin films

  • Lee, Y.J.;Choi, J.H.;Jun, B.H.;Joo, J.;Kim, C.S.;Kim, C.J.
    • Progress in Superconductivity and Cryogenics
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    • v.18 no.4
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    • pp.15-20
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    • 2016
  • The effects of electron beam (EB) irradiation on the superconducting critical temperature ($T_c$) and critical current density ($J_c$) of YBCO films were studied. The YBCO thin films were irradiated using a KAERI EB accelerator with an energy of 0.2 MeV and a dose of $10^{15}-10^{16}e/cm^2$. A small $T_c$ decrease and a broad superconducting transition were observed as the EB dose increased. The value of $J_cs$ (at 20 K, 50 K and 70 K) increased at doses of $7.5{\times}10^{15}$ and $2.2{\times}10^{16}e/cm^2$. However, $J_cs$ decreased as the dose increased further. The X-ray diffraction (XRD) analysis showed that the c axis of YBCO was elongated and the full width at half maximum (FWHM) increased as the dose increased, which is strong evidence of the atomic displacement by EB irradiation. The transmission electron microscopy (TEM) showed that the amorphous layer formed in the vicinity of the surfaces of the irradiated films. The amorphous phase was often present as an isolated form in the interior of the films. In addition to the formation of the amorphous phase, many striations running along the a-b direction of YBCO were observed. The high magnification lattice image showed that the striations were stacking faults. The enhancement of $J_c$ by EB irradiation is likely to be due to the lattice distortion and the formation of defects such as vacancies and stacking faults. The decrease in $J_c$ at a high EB dose is attributed to the extension of the amorphous region of a non-superconducting phase.

Quality Characteristics of Low-Dose Electron Beam Irradiated-Imported Navel Orange during Storage at Room Temperature (20℃) (저선량 전자선 조사 수입 오렌지의 상온저장 중 품질 특성)

  • Cho, Yun-Jeong;Kim, Kyung-Hee;Yook, Hong-Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.3
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    • pp.455-463
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    • 2015
  • This study investigated the effects of low-dose electron beam irradiation treatment on the physicochemical and sensorial properties of imported navel oranges during storage at $20^{\circ}C$ for 12 days. The samples were irradiated at doses of 0.2, 0.4, 0.6, 0.8, and 1.0 kGy, after which changes in color value, hardness, Brix/acid ratio, total sugar contents, reducing sugar contents, vitamin C contents, and sensory evaluation were investigated. There were no significant differences between non-irradiated and irradiated samples in terms of color value, Brix/acid ratio, total sugar contents, total reducing sugar contents, and vitamin C contents. Hardness of irradiated samples significantly decreased in the early storage period in an irradiation dose-independent manner, and the difference between non-irradiated and irradiated samples decreased again at the end of storage. For the sensory evaluation, there was no significant difference between non-irradiated and irradiated samples up to 0.6 kGy, and all sensory item scores decreased at the end of the storage period regardless of irradiation. These results suggest that electron beam irradiation below 0.6 kGy does not affect physicochemical and sensory properties during storage at $20^{\circ}C$. Thus, electron beam irradiation up to 0.6 kGy applied to imported navel oranges is the optimum dose for minimizing quality changes and disinfestation treatment.