• Title/Summary/Keyword: Non-Radiation

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The Effect of Gamma ray irradiation on Paper Properties (감마선 조사처리가 지류의 물성에 미치는 영향)

  • Jeong, Hye-Young;Choi, Kyoung-Hwa;Park, Ji-Hee;Jung, Pil-Mun;Choi, Jong-Il
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.3
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    • pp.43-49
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    • 2010
  • Recently, the use of fumigants for pest control of paper cultural heritages are limited because of the high toxicity of fumigants and the production of environment-harmfully compounds. Therefore, many non-chemical methods have been discussed and experimented. And it is recently focused on gamma radiation, which is one of non-chemical methods, for pest control of paper cultural heritage in Korea. In this paper, we carried out a gamma ray irradiation of papers including Hanji, copy paper, filter paper and then analyzed a physical properties and optical properties of paper sample to estimate the effect of gamma ray irradiation on paper properties. In result, gamma radiation have adverse effect on a physical properties and optical properties of paper, especially Hanji. Therefore, we have to carefully consider about using of gamma ray for pest control of paper cultural heritages.

AN ENGINEERING SCALE STUDY ON RADIATION GRAFTING OF POLYMERIC ADSORBENTS FOR RECOVERY OF HEAVY METAL IONS FROM SEAWATER

  • Prasad, T.L.;Saxena, A.K.;Tewari, P.K.;Sathiyamoorthy, D.
    • Nuclear Engineering and Technology
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    • v.41 no.8
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    • pp.1101-1108
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    • 2009
  • The ocean contains around eighty elements of the periodic table and uranium is also one among them, with a uniform concentration of 3.3 ppb and a relative abundance factor of 23. With a large coastline, India has a large stake in exploiting the 4 billion tonnes of uranium locked in seawater. The development of radiation grafting techniques, which are useful in incorporating the required functional groups, has led to more efficient adsorbent preparations in various geometrical configurations. Separation based on a polymeric adsorbent is becoming an increasingly popular technique for the extraction of trace heavy metals from seawater. Radiation grafting has provided definite advantages over chemical grafting. Studies related to thermally bonded non woven porous polypropylene fiber sheet substrate characterization and parameters to incorporate specific groups such as acrylonitrile (AN) into polymer back bones have been investigated. The grafted polyacrylonitrile chains were chemically modified to convert acrylonitrile group into an amidoxime group, a chelating group responsible for heavy metal uptake from seawater/brine. The present work has been undertaken to concentrate heavy metal ions from lean solutions from constant potential sources only. A scheme was designed and developed for investigation of the recovery of heavy metal ions such as uranium and vanadium from seawater.

An Experimental Study about The Effect of Solid Particle Seeding on Thermal Characteristics of Hydrogen Flame (고체 입자첨가가 수소화염의 열특성에 미치는 영향에 관한 실험적 연구)

  • Kim, Jung-Ju;Baek, Seung-Wook;Kim, Han-Seok;Choi, Joon-Won
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.26 no.11
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    • pp.1503-1512
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    • 2002
  • From the view of the environmental protection against the use of fossil fuels, a great of efforts have been exerted to find an alternative energy source. Hydrogen may become an alternative However the product species of the hydrogen flame is only $H_2O$, which emits only non-luminous radiation so the radiation from it is much smaller than that for a hydrocarbon flame. In this study, the authors designed and fabricated a laboratory scale test furnace to study thermal characteristics of hydrogen-air diffusion flame. In addition. the effects of addition of reacting as welt as non-reacting solid particles were experimentally investigated. Among the total heat flux to the wall, about 75 % was occupied by radiation while 25% by convection. When the aluminum oxide (Al$_2$O$_3$) particles were added, the radiative heat flux was reduced due to heat blockage effects. On the other hand, the total as well as the radiative heat flux was increased when the carbon particles were seeded, since the overall temperature increased. The effects of swirl and excess air ratio were also examined.

Toxicity Evaluation of High-Dose Irradiated Porridge Powder for Three Months (고선량 방사선 조사 분말 죽의 3개월 독성 평가)

  • Han Sag-Myung;Lee Ju-Woon;Byun Myung-Woo;Kang Il-Jun
    • Journal of the East Asian Society of Dietary Life
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    • v.15 no.4
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    • pp.431-436
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    • 2005
  • In order to evaluate their possible subacute toxicity, the male and female of SD rats were given to 30 kGy irradiated porridge for three months. During the experimental periods, appearance, behavior, mortality, food and water consumption of rats fed the 30 kGy porridge were not affected compared with the non-irradiated control. In urine analysis, hematological as well as in serum biochemical findings, no significant differences were found between the non-irradiate control and 30 kGy porridge group. Although minor changes in biochemical parameters were observed, they were in the normal ranges. These results indicate that porridge irradiated at 30 kGy did not show any toxic effects under these experimental conditions.

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Sterilization of Freeze Dried Manila Clam (Ruditapes philippinarum) Porridge for Immuno-Compromised Patients

  • Song, Beom-Seok;Park, Jae-Nam
    • Journal of Radiation Industry
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    • v.10 no.4
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    • pp.205-210
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    • 2016
  • This study was conducted to evaluate the combined effect of gamma irradiation and different conditions (vacuum packaging, antioxidant and freezing) on the microbiological and sensory characteristics of freeze dried Manila clam porridge (MCP) for immuno-compromised patient food. MCP can be sterilized at 1 kGy to 10 kGy. The initial counts of total aerobic bacteria and yeast molds in the non-irradiated MCP were $2.4{\pm}0.5$ and $1.2{\pm}0.3{\log}\;CFU\;g^{-1}$, respectively, but gamma irradiation significantly decreased the total aerobic bacteria to below the detection limit ($1{\log}\;CFU\;g^{-1}$) (5 kGy). Moreover, gamma irradiation effectively eliminated yeasts/molds at dose below than 1 kGy. However, gamma irradiation accelerated the increase of lipid oxidation and therefore, decreased the sensory characteristics of MCP as irradiation dose increased. To improve the sensory qualities of gamma irradiated MCP, combination treatment (vacuum packaging, 0.1% vitamin C) were applied. There was no significant difference in the overall acceptance scores between the combined-treatment sample (5.6 points) and the non-irradiated samples (6.0). The results indicate that combination treatment (vacuum packaging, 0.1% vitamin C) may help to maintain the quality of MCP. Therefore, it considered that irradiation of MCP with combined treatment and this is an effective method for the consumption as a special purpose food such as for space travel or immuno-compromised patients.

EFFECTS OF RADIATION AND HEAT GENERATION ON MHD AND PARABOLIC MOTION ON CASSON FLUIDS FLOW THROUGH A ROTATING POROUS MEDIUM IN A VERTICAL PLATE

  • J. PRAKASH;A. SELVARAJ
    • Journal of applied mathematics & informatics
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    • v.42 no.3
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    • pp.607-623
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    • 2024
  • This article studies the effects of heat generation/absorption and thermal radiation on the unsteady magnetohydrodynamic (MHD) Casson fluid flow past a vertical plate through rotating porous medium with constant temperature and mass diffusion. It is assumed that the plate temperature and concentration level are raised uniformly. For finding the exact solution, a set of non-dimensional partial differential equations is solved analytically using the Laplace transform technique. The influence of various non-dimensional parameters on the velocity are discussed, including the effects of the magnetic parameter M, heat generation/absorption Q, thermal radiation parameter R, Prandtl number Pr, Schmidt number Sc, permeability of porous medium parameter, Casson fluid parameter γ, on velocity, temperature, and concentration profiles, which are discussed through several figures. It is found that velocity, temperature, and concentration profiles in the case of heat generation parameter Q, Casson fluid parameter γ, thermal Grashof number Gr, mass Grashof number Gc, Permeability Porous medium parameter K, and time t have retarding effects. It is also seen that the magnetic field M, Thermal Radiation parameter R, Prandtl field Pr, Schmidt number Sc have reverse effects on it.

Usefulness assessment of the Volumetric Modulated Arc Therapy technique for reducing low-dose areas during radiotherapy for patients with multiple metastatic cancers (다발성 전이암 환자의 방사선치료 시 저선량 영역 감소를 위한 용적조절 회전 방사선치료(Volumetric Modulated Arc Therapy) 기법의 유용성 평가)

  • Yun-won Choi;Dong-min Jeong;Se-young Kim;Ryeong-hwang Park;I-ji Kim;Yong-wan Cho;Yongjae Kwon;Byeol-nim Park;Gyeong-min Yoo;Ho-kyung Moon;Dong-jae Jang;Jae-young Lee;Dayoung Lim;Sang-gyu Lee;Jong-geol Baek
    • The Journal of Korean Society for Radiation Therapy
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    • v.35
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    • pp.23-31
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    • 2023
  • Purpose: The purpose of this study is to evaluate the usefulness of Non-Treat Functionality Volumetric Modulated Arc Therapy(NTF-VMAT) and Treat Functionality VMAT(TF-VMAT) treatment plans in reducing the low-dose area during radiation therapy for patients with multiple metastatic cancers. Materials and Methods: The study was conducted on an Arccheck phantom, treatment planning target locations were set in pairs at intervals of 2 cm, 4 cm, and 6 cm on the X, Y, and Z axes. Based on these location settings, the volume of the low-dose area in NTF-VMAT and TF-VMAT was measured and compared. Results: The results of the study showed that, within a prescription dose range of 10% ~ 70%, the difference in low-dose area volumes across each axis was as follows: On the X-axis, there was a maximum difference of -47.6% and a minimum difference of -2.2%. On the Y-axis, there was a maximum difference of -17.5% and a minimum difference of -7.3%. The Z-axis showed a maximum difference of -39.7%, with the smallest difference being -6.8%. Conclusion: In radiation therapy for patients with multiple metastatic cancers, the TF-VMAT treatment plan was able to reduce the low-dose area by 10-40% compared to NTF-VMAT. This suggests that utilizing Treat Functionality, which includes the Island block technique, improves dose distribution and minimizes side effects, making it beneficial for the treatment of patients with multiple metastatic cancers.

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Prognostic value of neutrophil-to-lymphocyte ratio in locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy

  • Park, Eun Young;Kim, Yeon-Sil;Choi, Kyu Hye;Song, Jin Ho;Lee, Hyo Chun;Hong, Sook-Hee;Kang, Jin-Hyoung
    • Radiation Oncology Journal
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    • v.37 no.3
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    • pp.166-175
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    • 2019
  • Purpose: This study aimed to investigate neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as prognostic factors in patients with locally advanced non-small cell lung cancer (NSCLC) who received concurrent chemoradiotherapy (CCRT). Materials and Methods: We retrospectively analyzed 66 patients with locally advanced NSCLC treated with definitive CCRT. Among these patients, 95% received paclitaxel/carboplatin or docetaxel/cisplatin. The median radiation dose was 66 Gy in 33 fractions. The NLR and PLR before/after CCRT were evaluated. The maximally selected log-rank test was used to obtain the cutoff values related to the overall survival (OS). Results: Patients with high post-CCRT NLR (>3.12) showed worse OS, locoregional progression-free survival (LRPFS), and distant metastasis-free survival (DMFS) than those with low NLR (2-year OS: 25.8% vs. 68.2%, p < 0.001; 2-year LRPFS: 12.9% vs. 33.8%, p = 0.010; 2-year DMFS: 22.6% vs. 38.2%, p = 0.030). Patients with high post-CCRT PLR (>141) showed worse OS and LRPFS than those with low PLR (2-year OS: 37.5% vs. 71.1%, p = 0.004; 2-year LRPFS: 16.5% vs. 40.3%, p = 0.040). Patients with high NLR change (>1.61) showed worse OS and LRPFS than those with low NLR change (2-year OS: 26.0% vs. 59.0%, p < 0.001; 2-year LRPFS: 6.8% vs. 31.8%, p = 0.004). The planning target volume (hazard ration [HR] = 2.05, p = 0.028) and NLR change (HR = 3.17, p = 0.025) were the significant factors for OS in the multivariate analysis. Conclusion: NLR change after CCRT was associated with poor prognosis of survival in patients with locally advanced NSCLC. An elevated NLR after CCRT might be an indicator of an increased treatment failure risk.

Quality Improvement of Chicken Breast Meat in a Group-Meal Service by Gamma Irradiation (감마선조사에 의한 단체급식용 닭 가슴살의 품질 개선)

  • Kim Jang-Ho;Jeon Jin-Yong;Ryu Sang-Ryeol;Lee Ju-Woon;Kim Jae-Hun;Oh Sang-Hee;Seo Ji-Hyun;Byun Myung-Woo
    • Food Science and Preservation
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    • v.12 no.1
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    • pp.28-35
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    • 2005
  • The storage temperature significantly affected the microbiological quality of the chicken breast In the non-inadiated samples at $30^{\circ}C$, aerobic plate count (APC) and Echerichia coli count of the samples considerably increased during 3 days of storage and were eliminated by an irradiation at dose of 10 kGy or more. The APC and E coli count of the samples stored at $5^{\circ}C$ were reduced to below the limit of detection (< 2 log CFU/g) through the whole storage period by an irradiation at 5 kGy or mote. There was no significant difference in the TBA values between the non-inadiated and inadiated samples, which were not significantly higher in the irradiated samples than the non-inadiated samples during 2 weeks of storage at $5^{\circ}C$. According to the same-different test and acceptance test the sensory quality of the irradiated chicken breast was not significantly different from that of the non-inadiated sample even at 10 kGy. It is found that gamma irradiation is an effective tool to improve the quality of chicken breast in a group-meal service. It was also found that there was no evidence that an irradiation induced mutagenicity in the chicken breast meat.

Detection of Radiation Induced Markers in Oranges Imported from the United States of America (미국산 오렌지의 Radiation Induced Marker 검색)

  • 조덕조;권중호
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.32 no.1
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    • pp.1-7
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    • 2003
  • Radiation induced markers were investigated for the detection of irradiated oranges imported from America. In the DNA comet assay, the non-irradiated and irradiated samples showed the comets with long tails in both seed and flesh. Though this tendency was maintained for 6 weeks, identification of non-irradiated or irradiated samples was impossible. In the thermoluminescence (TL) measurement, the non-irradiated samples revealed a glow curve with low intensity at about 28$0^{\circ}C$, while the irradiated samples showed with higher intensity at around 18$0^{\circ}C$. There were no remarkable changes in detection properties for 6 weeks after irradiation. The TL ratio of area for TL$_1$ glow curve to TL$_2$ was below 0.1 for the non-irradiated samples and 0.5 or more for the irradiated ones during storage. In the electron spin resonance (RSR) measurement, irradiated oranges showed an unspecific central signal in all parts (seed, flesh and peel), so the detection for radiation treatment of oranges was impossible. Based on the results, DNA comet assay and ESR were not useful for the detection, but TL was appropriate to search radiation induced markers of oranges during storage period. The detectable period during storage is confirmed by sensory evaluation.