• Title/Summary/Keyword: electron beam(EB)

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Effect of UV-C and Electron Beam Irradiation of on the Quality of Rice Wine (Makgeolli) (UV-C 및 전자선 조사가 막걸리의 품질에 미치는 영향)

  • Kim, Hyun-Joo;Lee, Kyung Haeng;Yong, Hae In;Jo, Cheorun
    • Food Science and Preservation
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    • v.20 no.1
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    • pp.45-51
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    • 2013
  • This study was conducted to evaluate the changes in the quality of rice wine (Makgeolli) treated with UV-C and electron beam (EB) irradiation during its storage at $4^{\circ}C$ for 15 days. The EB irradiation was found to be more effective than the UV-C irradiation for microbiological control. The pH tended to be increased by UV-C, EB irradiation, and storage period. Acidity was significantly higher in rice wine treated with EB irradiation than those of control and UV-C irradiation during storage period. The $L^*$-value of the samples treated with UV-C and EB irradiation tended to be proportionately higher than that of the control, but this was not consistent during storage period. The $a^*$-value of the sample treated with EB was higher than that of the others, but this was not consistent during the storage period. The reducing sugar content was higher in the control at day 0, but it rapidly decreased compared with the control during the storage. The results indicate that EB irradiation was more effective than UV-C irradiation in controlling microorganisms of rice wine. However, a further study is needed to minimize the rice wine quality deterioration caused by UV-C or EB irradiation during storage.

Effect of Cationic Initiator Content on Electron-beam Curing of Difunctional Epoxy Resin (양이온 개시제 함량이 2관능성 에폭시 수지의 Electron-beam 경화에 미치는 효과)

  • Soo-Jin Park;Gun-Young Heo;Jae-Rock Lee;Dong Hack Suh
    • Journal of the Korean Chemical Society
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    • v.47 no.3
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    • pp.250-256
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    • 2003
  • In this work, the effect of cationic initiator content on the electron-beam (EB) curing process of diglycidylether of bisphenol-A (DGEBA) resin was studied using near-infrared spectroscopy (NIRS), thermogravimetric analysis (TGA), and critical stress intensity factor $(K_{IC})$. Benzylquinoxalinium hexafluoroantimonate (BQH) were used as an initiator and its content was varied from 0.5 to 3 phr. NIRS measurements showed that the hydroxyl group of EB-cured epoxy resin was increased with increasing the BQH content. Thermal stability and $K_{IC}$ value of EB-cured epoxy resin were increased with increasing the BQH content but were decreased above 2 phr content. These results could be attributed to the decrease of the conversion and degree of crosslinking. In another word, the conversion and degree of crosslinking were restricted by the incomplete network structure from high reactivity at the BQH content above 2 phr, resulting in decreasings of thermal stability and $K_{IC}$.

Cell Death of Human Promyelocytic Leukemia Cell after Low Dose of Electron Beam Irradiation with TNF-α (저 농도의 전자선을 조사한 전골수구성 백혈병 세포 죽음에서의 TNF-α 작용 효과)

  • Kim, Dong Hyun;Ko, Seong-Jin
    • The Journal of the Korea Contents Association
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    • v.14 no.6
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    • pp.241-246
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    • 2014
  • Acute promyelocytic leukemia (APL) is a cancer of the blood. Although electron beam (EB) irradiation is used with other anti-cancer agents, EB irradiation can be harmful to normal tissues around the cancer. In the present study, we evaluate the differential cytotoxic effect of EB irradiation with other molecules, including TNF-${\alpha}$, on DMSO-treated HL-60 cells and HL-60 cells. HL-60 cells are the human promyleocytic leukemia cell line and are differentiated by DMSO. DMSO-treated HL-60 cells are considered to be normal granulocytic cells. In these results, TNF-${\alpha}$ may be used as the potential agent for the treatment of blood cancer without side effects in low dose of EB irradiation therapy.

Effects of Electron Beam Irradiation and High-Pressure Treatment with Citrus Peel Extract on the Microbiological, Chemical and Sensory Qualities of Marinated Chicken Breast Meat

  • Kim, Hyun-Joo;Alahakoon, Amali U.;Jayasena, Dinesh D.;Khan, Muhammad I.;Nam, Ki Chang;Jo, Cheorun;Jung, Samooel
    • Korean Journal of Poultry Science
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    • v.42 no.3
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    • pp.215-221
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    • 2015
  • Chicken breast meat samples were injected with marinade solution (salt, sugar, phosphate, monosodium glutamate, and nucleic acid) with or without 2% citrus peel extract (CPE), and then a subset were irradiated with a 1 or 2 kGy electron beam (EB) and/or subjected to high-pressure (HP) at 300 or 400 MPa. The initial total aerobic bacterial (TAB) count of the control sample was 4.57 log CFU/g and reached 7.17 log CFU/g after 3 days of storage at $4^{\circ}C$. The 2 kGy EB reduced the TAB count to 4.61 log CFU/g after 7 days. The 400 MPa HP treatment was also effective in reducing the TAB count, but the effect was slightly less than that noted with the 2 kGy EB. The CPE, in combination with the EB and HP, decreased the TAB count by 1.71 and 1.32 log CFU/g at the initial stage and further decreased the count during storage. The 2 kGy EB and the HP (300 and 400 MPa) increased the thiobarbituric acid-reactive substances value, whereas the CPE did not show an antioxidative effect. The EB and HP caused no difference in the sensory qualities. In contrast, the CPE decreased all sensory qualities tested. Sensory panelists commented that the samples with CPE were not in the "rejection" category but were "unfamiliar" for chicken breast meat. In conclusion, the EB was more effective than HP in improving the microbial quality of marinated chicken breast meat. The use of CPE in the marinade solution may synergistically increase the shelf life; however, it is necessary to develop an appropriate formulation to ensure that the sensory qualities are maintained.

A Comparative Study on Electron-Beam and Thermal Curing Properties of Epoxy Resins (에폭시 수지의 전자선 및 열경화 특성에 관한 연구)

  • 이재락;허건영;박수진
    • Polymer(Korea)
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    • v.26 no.1
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    • pp.80-87
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    • 2002
  • A comparative study using electron-beam(EB) and thermal curing techniques was carried out to determine the effect of cure behavior and thermal stability of epoxy resins. In this work, benzylquinoxalinium hexafluoroantimonate(BQH) was used as a latent cationic catalyst for an epoxy resin. According to the thermogravimetric analysis(TGA), the decomposed activation energy based on Coats-Redfern method was higher in the case of thermal curing technique. This could be interpreted in terms of slow thermal diffusion rate resulted from high crosslink density of the thermally cured epoxy resin. However, the increase of hydroxyl group in the epoxy resin cured by EB technique was observed in near-infrared spectroscopy(NIRS) measurements, resulting in improving the stable short aromatic chain structure, integral procedural decomposition temperature, and finally ductile properties for high impact strengths.

Dynamic Mechanical Properties of Natural Fiber/Polymer Biocomposites: The Effect of Fiber Treatment with Electron Beam

  • Han, Young-Hee;Han, Seong-Ok;Cho, Dong-Hwan;Kim, Hyung-Il
    • Macromolecular Research
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    • v.16 no.3
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    • pp.253-260
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    • 2008
  • Environmentally friendly biocomposites were made using plant-based natural fibers, such as henequen and kenaf. The natural fiber reinforced polypropylene (PP) and unsaturated polyester (UP) biocomposites were examined in terms of the reinforcing effect of natural fibers on thermoplastic and thermosetting polymers. Kenaf (KE) and henequen (HQ) fibers were treated with an electron beam (EB) of 10 and 200 kGy doses, respectively, or with a 5 wt% NaOH solution. Four types of biocomposites (KE/PP, HQ/PP, KE/UP and HQ/UP) were fabricated by compression molding and each biocomposite was characterized by dynamic mechanical analysis and thermogravimetric analysis. The kenaf fiber had the larger reinforcing effect on the dynamic mechanical properties of both PP and UP biocomposites than the henequen fiber. The highest storage modulus was obtained from the biocomposite with the combination of UP matrix and 200 kGy EB treated kenaf fibers.

Effects of Electron-Beam Irradiation on Lipid Stability of Ginseng (Electron Beam 조사가 인삼분말의 지방질 안정성에 미치는 영향)

  • Lee, Mi-Kyung;Choi, Kang-Ju;Kim, Jeong-Sook;Kwon, Joong-Ho
    • Journal of Ginseng Research
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    • v.29 no.1
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    • pp.49-54
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    • 2005
  • Electron beam (EB), electrically produced from an electron accelerator, was compared with gamma ray (GR) in terms of its influence at doses from 0 to 15 kGy on the lipid stability of white and red ginseng powders. Irradiation (EB or GR) less than 10 kGy showed negligible effects on the composition of fatty acids in white and red ginseng powders. The thiobarbituric acid (TBA) value, however, increased with irradiation doses and storage time in both samples, which was more significant in red ginseng than white ginseng. Red ginseng revealed higher electron donating ability than white ginseng, even though there was insignificant difference between non-irradiated and irradiated samples irrespective of the post-irradiation storage for 4 months under room temperature as well as energy sources applied.

The domestic development of 60kw Electron Beam Welding System (고정밀 60kW급 전자빔 용접시스템 국산화 개발)

  • 정원희;엄기원;정인철
    • Proceedings of the KWS Conference
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    • 2001.10a
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    • pp.121-124
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    • 2001
  • The main characteristic of the Electron Beam Welding technique is its high energy density which produces thin and deep welds with very little distortion. High accelerated electrons, focused in a beam of 0.5 ∼ 2mm diameter, produce narrow welds with deep penetration. The result is a small HAZ as well as a low and uniform distortion which is predictible within very narrow limits. But the small diameter of the EB increases the requirements for the equipment control system for centering the beam on the welding joint in order to avoid any lack of fusion. Therefore, in this paper, we introduce the system developed at our company and the quality of welding zone, the detail function of system.

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Preparation and Characterization of Polyvinylidene Fluoride by Irradiating Electron Beam (전자빔 조사를 이용한 Polyvinylidene Fluoride의 제조 및 특성)

  • Choi, Yong-Jin;Kim, Min
    • Applied Chemistry for Engineering
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    • v.22 no.4
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    • pp.353-357
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    • 2011
  • For the purpose of introducing hydrophilic function to pristine PVDF, pristine PVDF was modified under atmosphere and aqueous vapor by irradiating electron beam (EB). EB dose was varied from 0 to 125 K Gray, respectively. Their changes of chemical composition /structure were observed and evaluated by FT-IR, EDS and DSC. Also, their surface behaviors were evaluated by contact angle. In FT-IR study, it was confirmed that hydroxyl functions were introduced to pristine PVDF. In EDS analysis, mole ratio of F (fluoride) was almost constant (about 33%) in spite of increasing EB dose, meaning that hydroxyl function was introduced via dehydrozenation, not via deflurodination. In DSC study, $T_g$ increased with increasing EB dose, which was reconfirmed that hydroxyl function was introduced via dehydrozenation. $T_m$ increased with increasing EB dose, inferring that the increase in EB dose led to more outbreak of hydroxyl function which led to more enhanced hydrogen bond. In the result of contact angle, pristine PVDF film was $62^{\circ}$ and 125 K Gray-irradiated PVDF film was even $13^{\circ}$. All results showed that pristine PVDF was successfully changed to hydrophilic PVDF.

Influence of different boost techniques on radiation dose to the left anterior descending coronary artery

  • Park, Kawngwoo;Lee, Yongha;Cha, Jihye;You, Sei Hwan;Kim, Sunghyun;Lee, Jong Young
    • Radiation Oncology Journal
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    • v.33 no.3
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    • pp.242-249
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    • 2015
  • Purpose: The purpose of this study is to compare the dosimetry of electron beam (EB) plans and three-dimensional helical tomotherapy (3DHT) plans for the patients with left-sided breast cancer, who underwent breast conserving surgery. Materials and Methods: We selected total of 15 patients based on the location of tumor, as following subsite: subareolar, upper outer, upper inner, lower lateral, and lower medial quadrants. The clinical target volume (CTV) was defined as the area of architectural distortion surrounded by surgical clip plus 1 cm margin. The conformity index (CI), homogeneity index (HI), quality of coverage (QC) and dose-volume parameters for the CTV, and organ at risk (OAR) were calculated. The following treatment techniques were assessed: single conformal EB plans; 3DHT plans with directional block of left anterior descending artery (LAD); and 3DHT plans with complete block of LAD. Results: 3DHT plans, regardless of type of LAD block, showed significantly better CI, HI, and QC for the CTVs, compared with the EB plans. However, 3DHT plans showed increase in the $V_{1Gy}$ at skin, left lung, and left breast. In terms of LAD, 3DHT plans with complete block of LAD showed extremely low dose, while dose increase in other OARs were observed, when compared with other plans. EB plans showed the worst conformity at upper outer quadrants of tumor bed site. Conclusion: 3DHT plans offer more favorable dose distributions to LAD, as well as improved target coverage in comparison with EB plans.