• Title/Summary/Keyword: 방사선처리법

Search Result 113, Processing Time 0.024 seconds

ESR-based Identification of Radiation-Induced Free Radicals in Gamma-Irradiated Basil and Clove Using Different Sample Pre-Treatments (감마선 조사된 바질과 정향의 전처리방법에 따른 ESR Spectra 판별 특성)

  • Kwak, Ji-Young;Ahn, Jae-Jun;Akram, Kashif;Kwon, Joong-Ho
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.41 no.10
    • /
    • pp.1454-1459
    • /
    • 2012
  • An improved detection of radiation-induced paramagnetic faults was developed to identify the irradiation status of basil and clove. The effectiveness of different sample pretreatments, including freeze-drying (FD), oven-drying (OD), alcoholic-extraction (AE), and water-washing and alcoholic-extraction (WAE), were examined. All non-irradiated samples showed a single central signal ($g_0$=2.006), whereas radicals representing two additional side peaks ($g_1$=2.023 and $g_2$=1.986) with a mutual distance of 6 mT were detected in the irradiated samples. AE and WAE produced the best results for irradiated clove in terms of intensities of radiation-specific ESR signals and their ratios to the central signal. However, FD provided the highest intensities of radiation-specific ESR signals for basil, whereas their ratios to the major signal were better in the cases of AE and WAE. Signal noise, particularly due to $Mn^{2+}$ signals, was observed, whereas it decreased in AE and WAE pretreatments. Based on our results, AE and WAE can improve the detection conditions for radiation-specific ESR signals in irradiated samples.

Study on the Facile Preparation of S-2-(${\omega}$-aminoalkylamino) ethyl Dihydrogen Phosphorothioates (티오인산이수소 S-2-(${\omega}$-아미노알킬아미노) 에틸들의 간편합성법 연구)

  • You Sun Kim;Suc Won Kim
    • Journal of the Korean Chemical Society
    • /
    • v.27 no.6
    • /
    • pp.449-456
    • /
    • 1983
  • The facile route of preparing S-2-(${\omega}$-aminoalkylamino) ethyl dihydrogen phosphorothioates, potential chemical radioprotectants, have been studied. Intermediate 3-(2-phthalimidoethyl)-2-oxazolidinone was prepared by a reaction of potassium phthalimide and 3-(2-bromoethyl)-2-oxazolidinone, which was obtained through the alkaline ring closure of a mixture of carbonate and 2,2'-dibromo diethylamine prepared from diethanolamine. This was converted to N-[2-(2-bromoethylamino)ethyl] phthalimide hydrobromide by 30% HBr(gas) in acetic acid and N-(2-bromoethyl)-1,2-ethanediamine dihydrobromide was obtained by reacting the hydrobromide with a solution of HBr-HOAc. N-(2-bromoethyl)-1,3-propanediamine dihydrobromide could be prepared through the Cortese treatment of 2-(3-aminopropylamino) ethanol, which was prepared by a reaction of 1,3-diaminopropane and 2-chloroethanol. These dihydrobromides were treated by sodium thiophosphate in DMF to result S-2-(${\omega}$-aminoalkylamino) ethyl dihydrogen phosphorothioates. The characteristics of each reaction path were discussed in regards to reaction conditions and overall yields and a facile route of preparing each derivative was proposed.

  • PDF

Study on Leaching Characteristics of $^{137}Cs\;and\;^{90}Sr$ from Cement-Solidified Radwastes (방사성 폐기물 시멘트 고화체로 부터의 $^{137}Cs$$^{90}Sr$ 용출특성 연구)

  • Hwang, Sun-Tae;Lee, Kyung-Ju;Choi, Kil-Oung;Park, Hun-Whee;Kim, Hwan-Young
    • Journal of Radiation Protection and Research
    • /
    • v.10 no.2
    • /
    • pp.113-121
    • /
    • 1985
  • For the safety assessment of radwaste treatment and disposal, the leaching characteristics of $Cs^+\;and\;Sr^{++}$ from the cement-solidified radwastes was investigated by means of the survey and analysis of the activity leach rate and cumulative leach fraction of $^{137}Cs\;and\;^{90}Sr$ leaching from solidified radwastes. The cylindrical cement-solidified samples were made by the sodium silicate method and neutralization method changing the mole density of simulated liquid radwaste, type of cement, adding material and concentration of boric acid. The leaching study was carried out by the method using simulated PWR concentrated liquid radwaste solidified in cement that had been processed following the recommendations of IAEA. All the experimental results are in well accordance with the research data reported previously, but the watertight cement-solidified radwastes show rather high leach rate of radioactivity. It is learned, therefore, that the watertight cement is not adequate as the material for the solidified radwastes.

  • PDF

Identification Characteristics of Irradiated Dried Red Pepper during Storage by the Analysis of Electron Spin Resonance and Hydrocarbons (전자스핀공명 및 Hydrocarbon 분석에 의한 방사선처리 건고추의 저장 중 검지특성)

  • Kim, Byeong-Keun;Lee, Jung-Eun;Kausar, Tusneem;Kim, Dong-Ho;Yang, Jae-Seung;Byun, Myung-Woo;Kwon, Joong-Ho
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.33 no.9
    • /
    • pp.1522-1528
    • /
    • 2004
  • Electron spin resonance (ESR) and hydrocarbon characteristics were analyzed to establish identification conditions for irradiated dried red pepper. The ESR spectroscopy for 4 different parts (powder, pericarp, seed, stem) of the samples showed that irradiated samples signaled (g=2.024, 2.006, 1.987) a pair of peaks from a cellulose radical at intervals of 6 mT, which were not found on the non-irradiated samples. The ESR signals increased in directly proportion to the irradiation doses, which were still detectable after 12 weeks of storage at room temperature. The GC-MS analysis of hydrocarbons after fat extraction and separation by florisil column chromatography revealed that hydrocarbons, such as 1-tetradecene (14:1), 1,7,10-hexadecatriene (16:3), 1,7-hexadecadiene (16:2), 1-hexadecene (16:1), 6,9-heptadecadiene (17:2), and 8-heptadecene (17:1), were detected only from the irradiated samples immediately after irradiation and 8 months of storage. They linearly increased with the dose of irradiation, suggesting them as radiation-induced markers for irradiated dried red pepper.

Metallurgical Characteristics and Manufacturing Techniques of Ring-Pommel Swords Excavated from Ancient Tombs in Hadae, Ulsan (울산 하대고분 출토 민고리자루칼의 재질 특성과 환두부 제작 방법)

  • Jo, Ha Nui;Kim, Han Seul;You, Ha Rim;Lee, Jae Sung
    • Journal of Conservation Science
    • /
    • v.36 no.3
    • /
    • pp.197-212
    • /
    • 2020
  • This study analyzed the microstructure of ring-pommel swords, excavated from Ancient Tombs, Hadae, Ulsan and examined their production technique, using non-destructive testing and a metallurgical method. The results confirmed that the five ring-pommel swords, unearthed in Ancient Tombs, Hadae, Ulsan, as identified by radiographic non-destructive testing, had been solely manufactured using iron, through forging based on the single-piece technique. Furthermore, these results were compared with previous studies, and the manufacturing techniques of single-piece ring-pommel swords were categorized into three types: pure iron - changing the shape, pure iron - changing the shape - carburization, and steel - changing the shape - quenching. The ring-pommels of four swords had around 0.7% of carbon content, which is as much as for eutectoid steel and higher than for other parts of these swords, such as the backs of their blades and handles. The weapon function of a small ring-pommel sword, under 60cm in length, was maximized by quenching focusing on its blade. Conversely, the martensite quenching structure was not observed in four ring-pommel swords shorter than 75cm. In other words, the same types of single-piece ring-pommel swords(late in 2C~early in 4C) were unearthed from Ancient Tombs, Hadae, and the group who has manufactured these swords is presumed to have limited their effectiveness, functionally depending on purposes, through an iron-making process and heat-treatment techniques.

A Study on Development of Guideline on Writing Technical Document for Electrical Medical Devices : Bone Absorptiometric X-ray System (엑스선골밀도측정기의 기술문서 작성을 위한 가이드라인 개발 연구)

  • Lee, Seung-Youl;Kim, Jae-Ryang;Kim, Eun-Rim;Lee, Jun-ho;Lee, Chang-Hyung;Park, Chang Won
    • Journal of radiological science and technology
    • /
    • v.39 no.2
    • /
    • pp.263-271
    • /
    • 2016
  • The market size of the bone absorptiometric X-ray system and the number of its approval by Ministry of Food and Drug Safety (MFDS) has annually increased, with a trend of increasing aging population and osteoporosis patients. For approval of manufactured or imported medical devices in Republic of Korea, it is required to submit its technical document. Therefore, it is need to develop the technical document guideline for the bone absorptiometric X-ray system for manufacturers, importers and reviewers. First of all, the technical documents which were already approved were examined and analyzed through MFDS approval administration system. Second, safety and performance test standards and methods that match international standards were drawn after conducting survey of the market status and the technology development trend for it, with examination and analysis of applicable domestic and overseas standards. Third, by operating industry-research-government cooperation, the guideline draft on writing technical document for the bone absorptiometric X-ray system was discussed, collecting their opinion. As a result, it is suitable to international and domestic condition, includes test evaluation methods and offer various information with appropriate examples to civil petitioner, when they write the technical documents.

Detection of Irradiated Dried Cereals from Korea and China by Viscometric Method (국산 및 중국산 곡류(기장 및 수수)의 감마선 조사 여부 검지를 위한 점도측정)

  • Kim, Hyun-Ku;Kang, Deog-Sun;Choi, Mal-Gum;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
    • /
    • v.33 no.6
    • /
    • pp.645-650
    • /
    • 2001
  • A study was carried out to establish the detection method for irradiated cereals. Cereals were ground and irradiated at 2.5, 5.0, 7.5, 10, 15 kGy using a $Co^{60}$ irradiator. The viscosities decreased in all samples by increasing irradiation dose. The viscosity of the Panicum millaceum (Korean) and Andropogon sorghum (Korean) paste dropped from $143.38{\pm}0.44$ and $35.92{\pm}1.90$ in the control to $6.60{\pm}1.16$ and $3.86{\pm}0.32$, respectively, in the samples irradiated at 15 kGy. These trends were similar to samples from china. Regression equation and coefficients of viscosity of Panicum millaceum (Korean and China) and Andropogon sorghum (Korean and China) were 0.80 (y=-27.789x+150.17), 0.98 (y=-3.367x+88.93), 0.84 (y=-6.0466x+35.49) and 0.84 (y=-13.346x+101.67) at 50 rpm. All samples resulted in a decrease in specific parameter by increasing rpm after irradiation. Parameter values showed dose-dependent relationship between unirradiated and irradiated samples and indicated that all values of unirradiated samples were higher than the irradiated ones. These results suggest that the detection of irradiated cereals at various doses using viscometric methods is possible.

  • PDF

Batch Scale Storage of Sprouting Foods by Irradiation Combined with Natural Low Temperature - II. Suitability for Potato Chip Processing of Irradiated Potatoes after Storage - (방사선(放射線) 조사(照射)와 자연저온(自然低溫)에 의한 발아식품(發芽食品)의 Batch Scale 저장(貯藏)에 관(關)한 연구(硏究) - 제2보(第二報) : 조사(照射)감자의 장기간(長期間) 저장후(貯藏後) Potato Chip 가공적성(加工適性)에 대하여 -)

  • Byun, Myung-Woo;Lee, Chul-Ho;Cho, Han-Ok;Kwon, Joong-Ho;Yang, Ho-Sook
    • Korean Journal of Food Science and Technology
    • /
    • v.14 no.4
    • /
    • pp.364-369
    • /
    • 1982
  • Two varieties of potatoes, Irish cobbler and Shimabara stored for seven and nine months respectively by irradiation combined with natural low temperature (year-round temperature change:$2{\sim}17^{\circ}C)$ on a batch scale were investigated on the suitability for processing of potato chip. Nine months after storage, irradiated potatoes (Irish cobbler) tended to maintain somewhat-better texture and sensory quality than untreated in potato chip processing. Peel rate, closely related to potato chip yield, of untreated potatoes were $20{\sim}25%$ higher than those of irradiated and Agtron color determination of potato chip from both irradiated were commercially acceptable. Preservation of potatoes by irradiation combined with natural low temperature was evaluated as an alternative method of the supply for raw materials of potato chip processing in the off season in Korea.

  • PDF

Development of Cardiac Digital Subtraction Angiographic System for Diagnosis of Cardiac Diseases (심장병 진단을 위한 실시간 디지탈 감산 조영 영상기법의 개발)

  • Min, Byoung-Goo;Lee, Tae-Soo
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.26 no.2
    • /
    • pp.132-139
    • /
    • 1989
  • We have designed a real-time Cardiac digital substraction angiography system (C-DSA) and tested the system for the diagnosis of Cardiac patients. The system was developed by interfacing a radiographic angiography system to a computerized motional image analysis system. This new cardiac DSA can perform the real time processing of averaging and subtraction of the 32 image frames to measure the volume changes of the left ventricle after elimination of motional artrifacts, caused by the heart contraction of beats per minute in average. Each frame has a resolution of 512 x 512 pixels and 256 gray levels. Two image data with maximal and minimal volume were moved to the interfaced IBM PC computer system by high speed computer link line for computation of the heart's contraction parameters. First, the boundary of the left ventricule was detected using a dynamic programming of the gray levels, and its volume was computered to determine the parameters, such as the maximal volume of end-diastolic volume (EDV), the minimal volume of end systolic volume (ESV), and ejection fraction (EF).

  • PDF

Quality Stability of Spinach Powder As Influenced by Microbial Decontamination Treatment (시금치 분말의 품질안정성에 대한 살균처리의 영향)

  • Kwon, Joong-Ho;Byun, Myung-Woo;Cho, Han-Ok;Choi, Jong-Uck
    • Korean Journal of Food Science and Technology
    • /
    • v.26 no.2
    • /
    • pp.167-171
    • /
    • 1994
  • With a view to improving microbiological quality of spinach powder which is currently used for convenience food production, comparative efficacy of ethylene oxide(EO) fumigation and gamma irradiation was investigated by determining microbial populations and physicochemical quality for treated samples. Spinach powder was contaminated with various microorganisms ranging from $10^{2}/g\;to\;10^{4}/g$, which composed of thermophiles, acid tolerant bacteria, fungi, coliforms, etc. Microorganisms contaminated were destroyed up to undetected levels by gamma irradiation at below 7 kGy. showing the radiosensitivity $D_{10}$ 2.93 kGy on total aerobic bacteria. Ethylene oxide fumigation, however. was found unsatisfactory for physicochemical quality as well as microbial decontamination of the sample. It has been generally observed that influence of optimum-dose range of irradiation on the physicochemical qualities was insignificant, which was proved in the organoleptic evaluations on the stored sample.

  • PDF