극저준위 방사성폐기물을 위한 효율적인 γ-선 및 β-선 측정방법 개발

곽성우,염유선,김호경,조규성,박주완,김창락,송명재 대한방사선 방어학회 2001 방사선방어학회지 Vol.26 No.4

매년 병원에서 사용 후 폐기되는 비가연성 폐기물은 r -선과 β-선을 방출하지만 방사능은 주변방사능 수준으로 매우 낮다. 이를 측정하기 위한 기존의 방법은 비효율적이고 복잡하므로, 좀 더 간단한 방법이 긴요하다. 본 논문에서는 측정 방사선의 특성상 핵종에 따라 다른 측정방법을 사용하였는데, r-선 방출 핵종은 표준시료로부터 효율곡선식을 도출하여 미지의 방사능을 측정하였다. β-선 방출 핵종은 Monte Carlo 시뮬레이션을 통해 계측 효율을 예측하고 표면장벽형계측기로 측정하여 미지의 방사능 양을 결정하는 새로운 방법을 제시하였다. 연구결과에 의하면 이론적 계산치와 표면장벽형계측기를 이용하면 전처리를 필요로하는 액체섬광계수기를 이용하지 않고 또한 계측효율을 결정하기 위한 비경제적인 표준시료 측정시험과정 없이도 저에너지 방사선을 약 17% 오차 범위내에서 결정할 수 있다고 판단된다. The non-combustible RI wastes disposed of in hospital every year emit r -ray or β -ray but their activities are very low to the extent of background. Development of more simple methods is needed because the conventional detection methods are so ineffective and complex. In this study, to solve this problem, detection method using efficiency curve for r -ray emitting radioactive wastes measurement is proposed and experimental detection efficiency equation is also determined through HPGe's standard specimen measurement. For β-emitting radioisotopes detection, new measurement method using detection efficiency estimated by Monte Carlo simulation and SBD measurements is also proposed. According to the results of this paper, the unknown activity of low-level radioactive wastes without LSC requiring the preparation of standard sample and measurement for standard source detection efficiency could be determined efficiently and simply about ±17% in errors by using the theoretical detection efficiency and the SBD measurement result.

X-ray 및 TEM 을 이용한 Zr-2.5Nb 압력관의 전위밀도 및 β-Zr 상의 조성 결정

김영석,정용무,김성수,임경수 대한금속재료학회 2002 대한금속·재료학회지 Vol.40 No.2

The dislocation density and the composition of the β-Zr phase in Zr-2.5Nb pressure tubes were determined using a X-ray diffractometer and TEM. Through Fourier analysis of diffraction line profiles of {11-20}, {10-10} and {0001} planes, the coherent block size and the lattice strain energy were evaluated. Using those values, then, the a-and c-type dislocation densities were determined for an unirradiated Zr-2.5Nb pressure tube, which were consistent with the independently measured values for the same specimen using the AECL's own method. TEM analysis showed that the a- and c-type dislocation densities in the Zr-2.5Nb tube are 4.0×10 exp (14) m^-2 and 0.97×10 exp (14) m^-2, respectively, which could not be compared directly with the dislocation densities determined by an X-ray analysis. The Nb content of the β-Zr phase was determined using an X-ray from a change in the interplanar spacing of the {100} planes, which agrees well with that determined by TEM using the carbon replica method.

PM10 연속자동측정기(β-ray) 등가성평가 및 비교관측 연구

정원석,고희정,서원익,정지영,오상민,부경온 한국입자에어로졸학회 2023 Particle and Aerosol Research Vol.19 No.1

The Asian dust observation network operates β-ray attenuation samplers to measure PM10 concentrations. In addition, equivalence evaluation and accuracy inspection(Precision Tests) are conducted every year for the reliability of data. β-ray attenuation samplers(16 units) were comparatively observed from May to June 2020 and from July to December 2021. During the observation period, the average daily temperature was the lowest at 6.4℃ in December and the highest at 27.3℃ in August. The average daily humidity ranged from 60% to 100%, but the average daily humidity was over 75% from July to September. The minimum value of the PM10 Gravimetric method was 5.0 μg/m3, the maximum value was 53.4 μg/m3, and the average value was 17.8 μg/m3. The equivalence evaluation results of the PM10 Gravimetric method and β-ray attenuation samplers satisfied the criteria (slope: 1±0.1, intercept: 0±0.5). A relative error analysis between the PM10 Gravimetric method and β-ray attenuation samplers equipment showed that the relative error increased when the concentration was low and the temperature and humidity were high. In addition, in the β-ray attenuation samplers 5-minute interval observation data in May 2020, a relatively large Standard devication was shown as an average maximum ±23.4 μg/m3 and a minimum ±15.2 μg/m3. At standard deviations of 10% and 90%, equipment with high variability (deviation) was measured at 6 μg/m3and 61 μg/m3, and equipment with low variability was measured at 12 μg/m3 and 47 μg/m3. It was confirmed that concentration differences occurred due to differences in variability for each equipment.

Determination of Gross-β and γ-Ray Activity Concentrations of Human Tooth

Hyunja Jeong(정현자),Hyun-Kyung Kang(강현경),Sunghwan Kim(김성환) 대한방사선과학회(구 대한방사선기술학회) 2014 방사선기술과학 Vol.37 No.4

The γ-ray concentration and gross-β activity by age group were measured in the teeth of males and females of the domestic residents. They were divided into 7 age groups from 10s to the age of 70s. The gross-β activity concentration was measured by using the Tennelec XLB measuring instrument filled with P10 gas (argon 90%, methane 10%). The γ-ray was measured through the γ-ray spectroscopic analytical method by using the high purity germanium (HPGe) radiation detector. The range of gross-β activity con-centration was measured 0.089 to 0.32 Bq/kg in females and 0.13 to 0.26 Bq/kg in males. From the γ-ray spectroscopic analysis of the teeth, the natural radioactive isotopes of 40 K, 208 Tl, 228 Ac and 234 Th were de-tected and their measured γ-ray activity concentrations were found to be 20.7, 21.9, 3.88 and 5.24Bq/kg, respectively. 10세에서 70세까지 국내 남녀를 7개 연령대별 그룹으로 구분한 후, 치아의 감마선 농도와 각 그룹별 전β 방사능 농도를 측정하였다. 전β 농도는 P10가스(아르곤 90%, 메탄 10%)를 충진한 Tennelec XLB 측정기로 측정하였으며, 감마선은 고순도 게르마늄 검출기를 사용하여 감마선분광분석법으로 측정하였다. 본 실험에서 측정된 여성의 전β 방사능 농도범위는 0.089~0.32 Bq/kg이었으며, 남성의 전β 방사능 농도범위는 0.13~0.26 Bq/kg이었다. 치아의 감마선분광분석 결과 자연방사성동위원소인 40K,208Tl,228Ac 및234Th가 검출되었으며, 측정된 감마선 방사선 농도는 각각 20.7, 21.9 3.88 및 5.24 Bq/kg 이었다. 본 연구 결과는 향후 후쿠시마 원 전사고 등 불의의 방사선 누출 사고 등에 대비하여 정상 환경에서의 인체의 치아에 축적된 방사능 준위 데이 터로 활용할 수 있을 것으로 사려된다.

Development of Effective γ-ray and β-ray Detection Methods For Low-Level Radioactive Wastes

Sung Woo Kwak,Yu Sun Yeom,Ho Kyung Kim,Gyuseong Cho,Joo Wan Park,Chang Lak Kim,Myung Jae Song 대한방사선방어학회 2001 방사선방어학회지 Vol.26 No.4

저 선량 베타선의 조사에 의한 식물의 생장에 미치는 영향

이병구(Byung-Koo Lee),임인철(In-Chul Im),김종언(Jong-Eon Kim) 대한방사선과학회(구 대한방사선기술학회) 2010 방사선기술과학 Vol.33 No.2

본 연구는 저 선량 베타선의 장기간(31일) 조사에 의한 춘향이 열무와 알타리 무의 생장에 미치는 영향을 분석하는데 목적이 있다. 실험은 알타리 무와 춘향이 열무에 대하여 각각 1개 샘플의 대조군과 11개 샘플의 실험군으로 구성하였다. 대조군과 실험군의 종자들은 각각의 샘플에서 8개씩 선택되어 같은 조건의 배양토에 파종하였다. 실험군 샘플의 누적선량은 31일 동안 매일 같은 시간에 측정하였다. 생장과정과 발아율은 매주 2회 같은 시간에 측정하였다. 잎사귀 수, 초장의 길이와 생체중은 파종 후 20일과 25일에 각각 측정하여 평균값을 얻었다. 25일 동안 측정된 실험군의 결과에서, 알타리 무의 길이와 무게는 누적선량 0.01 Gy에서 대조군보다 각각 5%와 36%로 증가하였다. 또한 춘향이 열무에서 길이는 누적선량 0.01~0.08 Gy와 0.3 Gy에서 대조군보다 각각 13~17%와 1%, 무게는 누적선량 0.05 Gy와 0.23 Gy에서 대조군보다 각각 36%와 2%로 증가하였다. 잎 수에 대하여, 알타리 무는 누적선량 0.01~0.32 Gy에서 대조군보다 0~50%로 증가하였다. 그리고 춘향이 열무는 0.01~0.0.62 Gy에서 대조군보다 0~67%로 증가하였다. 이 결과로부터, 알타리 무와 춘향이 열무는 대체적으로 낮은 누적선량영역(0.01~0.2 Gy)에서 길이와 무게 그리고 잎 수가 증가하였다. 그리고 실험군의 세포의 크기,핵의 위치와 세포의 조밀도는 대조군과 거의 유사하게 현미경으로 관찰되었다. 결론적으로, 베타선에 조사된 알타리 무와 춘향이 열무는 방사선 호메시스 이론과 부합되어 낮은 누적선량영역에서 더 많은 생장을 한 것으로 추정된다. 추후 연구에서 방사선 호메시스와 식물생장의 관련성을 확증하기 위한 추가적인 실험이 필요할 것으로 생각된다. This study is to analyze effects of the growth of Chunhyang Young Radish (CYR) and Altari Radish (AR) according to the exposure for 31 days at low dose β-rays. This test has one contrast sample and eleven test samples each as to AR and CYR. The seeds from contrast and test sample were planted in the culture soil after 8 seeds were chosen from each with identical condition. The accumulated dose of test samples has been measured at consistent time on a daily basis for 31 days. The growing process and germination have been measured twice at consistent time in each week. The number of leaves, length of first leave and weight have been acquired average value by measuring for 20 and 25 days, respectively after being planted. The result of test sample in case of 25 days shows that 5% increase in length and 36% increase in weight for AR each at accumulated dose 0.01 Gy compared to the contrast sample. And the length of CYR has increased by 13~17% and 1% at accumulated dose 0.01~0.08 Gy and 0.3 Gy compared to the contrast sample. For the weight at accumulated dose 0.05 Gy and 0.23 Gy has increased by 36% and 2% compared to contrast sample. As to the number of leaves, AR has increased by 0~50% at accumulated dose 0.01-0.32 Gy compared to contrast sample. It also shows that the CYR has increased to 0~67% at accumulated dose 0.01-0.62 Gy compared to contrast sample. As a result of this study, it indicates that both AR and CYR has generally increased in their length, weight, and the number of leaves at low level accumulated dose part 0.01~0.2 Gy. The size of cell, area of nucleus and density of cell for test sample has been observed quite similar to the ones from contrast sample through microscope. In conclusion, AR and CYR irradiated by β-rays have estimated that they are achieved a rapid growth at low level accumulated dose region corresponding to its radiation hormesis theory. Further studies need to confirm the correlation between the radiation hormesis and the growth of the plants.

생체용 Ti-Ta-Mo-Zr 합금 개발에 관한 연구

원대희 한국기계기술학회 2016 한국기계기술학회지 Vol.18 No.3

This study was purposed to develope a titanium alloy with low elastic modulus to be used as dental implant. The new titanium alloy was prepared as titanium alloy by adding Tantalum(Ta), Zirconium(Zr), Molybdenum(Mo) into the Ti-X-Y-Z system alloys. In designing the new titanium alloys, two physical variables bond order (Bo) and d-electron orbit energy level (Md) were varied. Mean bond order ( ) was around 2.818∼2.8784eV, and Mean d-electron orbit energy level ( ) was 2.4541~2.4747eV. In the cases of titanium alloys of T-3M and T-3Z, the XRD analysis showed β phase. On the other hand, the phase of α+ β were observed in the T-6Z and T-8Z alloys. Exhibited the highest hardness value to result in T-3Z 309.7Hv alloy Vickers hardness with respect to titanium alloy. In the resulting T-3Z alloy of measuring the elastic modulus value for a titanium alloy exhibited the smallest modulus of elasticity value to 89.81GPa. TEM analysis identified additional feature for T-3Z alloy was detected in addition to the ß-phase.

124Te 핵의 다중 입자 준위

문창범 한국물리학회 2009 새물리 Vol.59 No.5

The excited states of the nucleus 124Te have been studied by using in-beam gamma-ray spectroscopy with the 122Sn (7Li, p4n) 124Te reaction at Elab = 54 MeV. Several states above Iπ = 10+ at 3154 keV have been newly identified. The resulting level scheme was interpreted in the frame work of energy systematics and Total Routhian surface(TRS) calculations. The Iπ = 10+ level is consistent with the systematic trend in 118-122Te and thus interpreted as being based on the two-quasineutron h11/2 orbital, namely ν(h11/2)2 configuration. The Iπ= 16+ level at 5480 keV was found not to be energetically favored but to be a little higher in energy than those in light isotopes of 118-122Te. This state was suggested as being a noncollective oblate state based on the four-quasiparticle [π(g7/2)2]6+×ν[(h11/2)2]]10+ configuration. 124Te의 들뜬 상태들이 감마선 분광학에 의해 조사되었다. 사용된 핵반응은122Sn (7Li, p4n) 124Te이고 사용된 빔 에너지는 54 MeV 이었다. 본 연구를 통하여 Iπ = 10+ 이상의 고스핀 상태들이 처음으로 발견되었다. 총회전틀에너지분포(TRS) 계산에 의하면, Iπ= 10+ 준위는 h11/2 궤도의 두-준중성자의 들뜸 즉 ν(h11/2)2으로 생성된 것임을 알 수 있었다. 스핀-반전성이 Iπ= 16+ 준위는 그 들뜸 에너지가 5480 keV로 비집단적 성질을 보였으나 보다 낮은 동위원소들인 118-122Te 에서 보이는 들뜸 에너지 경향보다는 다소 높은 수준을 보였다. 이러한 성질은 g7/2궤도의 두개의 양성자와 h11/2 궤도에 있는 두개의 중성자가 결합을 한 네-준입자 [π(g7/2)2]6+×ν[(h11/2)2]]10+ 배열에 의한 들뜸 상태로 해석되었다.

Coordination of an Amino Alcohol Schiff Base Ligand Toward Cd(II)

Zahra Mardani,Mohammad Hakimi,Keyvan Moeini,Fabian Mohr 대한화학회 2019 대한화학회지 Vol.63 No.1

A potentially tetradentate Schiff base ligand, 2-((2-((pyridin-2-ylmethylene)amino)ethyl)amino)ethan-1-ol (PMAE), and its cadmium(II) complex, [Cd(PMAE)I2] (1), were prepared and characterized by elemental analysis, FT-IR, Raman, 1H and 13C NMR spectroscopies and single-crystal X-ray diffraction. In the crystal structure of 1, the cadmium atom has a slightly distorted square-pyramidal geometry and a CdN3I2 environment in which the PMAE acts as an N3-donor. In the crystal packing of the complex, the alcohol and amine groups of the coordinated ligands participate in hydrogen bonding with iodide ions and form R2 2(14) and R2 2(8) hydrogen bond motifs, respectively. In addition to the hydrogen bonds, the crystal network is stabilized by π–π stacking interactions between pyridine rings. The thermodynamic stability of the isolated ligand and its cadmium complex along with their charge distribution patterns were studied by DFT and NBO analysis.

β-irradiation (166Ho patch)-induced skin injury in mini-pigs: effects on NF-κB and COX-2 expression in the skin

김중선,임경진,장원석,이선주,손영훈,이승숙,박선호,임상무 대한수의학회 2015 Journal of Veterinary Science Vol.16 No.1

In the present study, the detrimental effect of β-emission on pig skin was evaluated. Skin injury was modeled in mini-pigs by exposing theanimals to 50 and 100 Gy of β-emission delivered by 166Ho patches. Clinicopathological and immunohistochemical changes in exposed skinwere monitored for 18 weeks after β-irradiation. Radiation induced desquamation at 2∼4 weeks and gradual repair of this damage was evident6 weeks after irradiation. Changes in basal cell density and skin depth corresponded to clinically relevant changes. Skin thickness began todecrease 1 week after irradiation, and the skin was thinnest 4 weeks after irradiation. Skin thickness increased transiently during recoveryfrom irradiation-induced skin injury, which was evident 6∼8 weeks after irradiation. Epidermal expression of nuclear factor-kappa B (NF-κB)differed significantly between the untreated and irradiated areas. One week after irradiation, cyclooxygenase-2 (COX-2) expression wasmostly limited to the basal cell layer and scattered among these cells. High levels of COX-2 expression were detected throughout the full depthof the skin 4 weeks after irradiation. These findings suggest that NF-κB and COX-2 play roles in epidermal cell regeneration followingβ-irradiation of mini-pig skin.