• Title/Summary/Keyword: 방사선시험

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Preparation and Characterization of Microorganism Fermentation Cellulose as Hydrogel Wound Dressing (미생물 발효 셀룰로오스를 이용한 상처 치료용 하이드로겔의 제조 및 특성)

  • Kim, Mi-Yeong;Lim, Youn-Mook;Lee, Jong-Dae;Song, Sung-Gi;Gwon, Hui-Jeong;Park, Jong-Seok;Nho, Young-Chang;Kim, Sung-Ho;Choi, Young-Hun;Lee, Sun-Yi
    • Journal of Radiation Industry
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    • v.4 no.4
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    • pp.365-372
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    • 2010
  • Irradiation has been recognized as a highly suitable tool to aid in the formation of hydrogel. The radiation process has various advantage, such as easy process control and the lack of necessity for initiators and crosslinker. In this study, the hydrogel containing the citrus fermentation gel for the wound healing were successfully synthesized. The strength of hydrogel was increased as a function of a increasing the concentration of citrus and the irradiation doses. In addition, this hydrogel have been evaluated by the cytotoxicity and animal experiment.

An Experimental Study of Radioprotective Effect of Ginseng Alkaloid Fraction on Cellular Damage (방사선 세포 손상에 대한 인삼 Alkaloid 분획의 보호 효과에 관한 실험적 연구)

  • Yoo, Seong-Yul;Cho, Chul-Koo;Kim, Mi-Sook;Yoo, Hyung-Jun;Kim, Seong-Ho;Kim, Tae-Hwan
    • Journal of Radiation Protection and Research
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    • v.22 no.3
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    • pp.195-205
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    • 1997
  • This paper is to assess the effect of Adaptagen as a radioprotector in which main component is alkaloid fraction of ginseng. Evaluation was made in vitro and in vivo study with NIGP(S) mouse by the measurement of regeneration of jejunal crypt cell and micronucleus assay to analyze radioprotective effect of ginseng alkaloid fraction in comparison with that of water fraction after whole body irradiation. The results were as follows, 1. The degree of radiation damage of mouse jejunal crypt cell was diminished in both of alkaloid and water fraction groups compared to control group but more in alkaloid fraction group than water fraction group. Regeneration of mouse jejunal crypt cell was higher both in alkaloid and water fraction groups than control group. 3. In vitro study, frequency of micronucleus was diminished in tendency for the treated groups than control group but statistically insignificant. 4. In vitro study, frequency of micronucleus was diminished in both alkaloid and water fraction groups compared to control group but more in alkaloid fraction group than water fraction group.

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Application of SP Monitoring in the Pohang Geothermal Field (포항 지열 개발지역에서의 SP 장기 관측)

  • Lim Seong Keun;Lee Tae Jong;Song Yoonho;Song Sung-Ho;Yasukawa Kasumi;Cho Byong Wook;Song Young Soo
    • Geophysics and Geophysical Exploration
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    • v.7 no.3
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    • pp.164-173
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    • 2004
  • To delineate geothermal water movement at the Pohang geothermal development site, Self-Potential (SP) survey and monitoring were carried out during pumping tests. Before drilling, background SP data have been gathered to figure out overall potential distribution of the site. The pumping test was performed in two separate periods: 24 hours in December 2003 and 72 hours in March 2004. SP monitoring started several days before the pumping tests with a 128-channel automatic recording system. The background SP survey showed a clear positive anomaly at the northern part of the boreholes, which may be interpreted as an up-flow Bone of the deep geothermal water due to electrokinetic potential generated by hydrothermal circulation. The first and second SP monitoring during the pumping tests performed to figure out the fluid flow in the geothermal reservoir but it was not easy to see clear variations of SP due to pumping and pumping stop. Since the area is covered by some 360 m-thick tertiary sediments with very low electrical resistivity (less than 10 ohm-m), the electrokinetic potential due to deep groundwater flow resulted in being seriously attenuated on the surface. However, when we compared the variation of SP with that of groundwater level and temperature of pumping water, we could identify some areas responsible to the pumping. Dominant SP changes are observed in the south-west part of the boreholes during both the preliminary and long-term pumping periods, where 3-D magnetotelluric survey showed low-resistivity anomaly at the depth of $600m\~1,000m$. Overall analysis suggests that there exist hydraulic connection through the southwestern part to the pumping well.

Comparison Research of SNR and SRb with Bright Calibration and Multi Frame Images in Digital Radiography of Welded Test Components (용접 시험편의 디지털 방사선 검사에서 밝기 교정과 중첩 영상에 따른 SNR 및 SRb 비교 연구)

  • Nam, Mun-Ho;Yang, Jin-Wook;Cho, Kap-Ho
    • Journal of the Korean Society of Radiology
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    • v.15 no.5
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    • pp.731-739
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    • 2021
  • This work compared the bright calibration of digital radiation with signal-to-noise ratio and basic spatial resolution according to multi frame to enable effective inspection of welding parts of structures at industrial sites. A total of 130 images were obtained by using a 75Se radiation source for flat weld test pieces and segmenting bright calibration and multi frame prior to shooting. The study confirms that the signal-to-noise ratio improves as the number of bright calibrations and the number of multi frame increases. The basic spatial resolution satisfied the baseline for both radiographic images. It was confirmed that the number of signal-to-noise ratio was similar by comparing images taken after installing lead shielding for scattering radiation. Although signal-to-noise ratio increases as multi frame increases, it is believed that good quality digital radiographs can be obtained if appropriate radiographic techniques are devised because exposure time of radiation affects workers' exposure and work efficiency.

Quality Control Tests and Acceptance Criteria of Diagnostic Radiopharmaceuticals (진단용 방사성의약품의 품질관리시험 및 기준)

  • Park, Jun Young
    • Korean Journal of Clinical Laboratory Science
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    • v.53 no.1
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    • pp.1-10
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    • 2021
  • Radiopharmaceuticals are drugs that contain radioisotopes and are used in the diagnosis, treatment, or investigation of diseases. Radiopharmaceuticals must be manufactured in compliance with good manufacturing practice regulations and subjected to quality control before they are administered to patients to ensure the safety of the drug. Radiopharmaceuticals for administration to humans need to be sterile and pyrogen-free. Hence, sterility tests and membrane filter integrity tests are carried out to confirm the asepticity of the finished drug product, and a bacterial endotoxin test conducted to assess contamination, if any, by pyrogens. The physical appearance and the absence of foreign insoluble substances should be confirmed by a visual inspection. The chemical purity, residual solvents, and pH should be evaluated because residual by-products and impurities in the finished product can be harmful to patients. The half-life, radiochemical purity, radionuclidic purity, and strength need to be assessed by analyzing the radiation emitted from radiopharmaceuticals to verify that the radioisotope contents are properly labeled on pharmaceuticals. Radiopharmaceuticals always carry the risk of radiation exposure. Therefore, the time taken for quality control tests should be minimized and care should be taken to prevent radiation exposure during handling. This review discusses the quality control procedures and acceptance criteria for a diagnostic radiopharmaceutical.