• Title/Summary/Keyword: Gamma Counter

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A Study on the Interface Properties of Metal/Organic Films/Metal (Metal/Organic Films/Metal에서 계면특성에 관한 연구)

  • Song, Jin-Won;Cho, Su-Young;Choi, Young-Il;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.07b
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    • pp.723-726
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    • 2002
  • We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 10[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Poly-$\gamma$ Benzyl $_D$-Glutamate/Al; the number of accumulated layers is 1, 3, 5 and 7. Also, we then examined of the MIM device by means of I-V. The I-V characteristic of the device is measured from 0 to +2[V]. We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. LB film accumulated by monolayer on an ITO. In the cyclicvoltammetry, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode measured in $LiBF_4$ solution, stable up to 0.9V vs. Ag/AgCl.

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Distribution of natural radioactivity in soil and date palm-pits using high purity germanium radiation detectors and LB-alpha/beta gas-flow counter in Saudi Arabia

  • Shayeb, Mohammad Abu;Baloch, Muzahir Ali
    • Nuclear Engineering and Technology
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    • v.52 no.6
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    • pp.1282-1288
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    • 2020
  • In the first study, the Radon emanation and radiological hazards associated with radionuclides in soil samples, collected from 9 various date palm farms located in 3 different districts in Saudi Arabia were determined through a high purity Germanium (HPGe) gamma-ray spectrometer. The estimated average values of Radon emanation coefficient and Radon mass exhalation rate for soil samples were 0.535 ± 0.016 and 50.063 ± 7.901 mBqkg-1h-1, respectively. The annual effective dose of radionuclides in all sampling locations was found to be lower than UNSCEAR's recommended level of 0.07 mSvy-1 for soil in an outdoor environment. In the secondary study, gross α and gross β activities in soil and date palm pits samples were measured by a low background α/β counting system. Average values of gross α and gross β activities in soil and date palm pits samples were 5.761 ± 0.360 Bqkg-1, 38.219 ± 8.619 Bqkg-1 and 0.556 ± 0.142 Bqkg-1, 24.266 ± 1.711 Bqkg-1, respectively.

Qunntitation of Fentanyl Remaining in Used Patches (Fentanyl Patch의 사용후 잔량분석)

  • Bae, Yang Soo;Ahn, Jung Soon;Choi, Kyung Eob
    • Korean Journal of Clinical Pharmacy
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    • v.6 no.2
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    • pp.24-27
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    • 1996
  • In order to determine whether there was a clinically sufficient amount of drug remaining in used fentanyl patches, quantitative analysis of two different types of patches, each containing 2.5 mg (n=36) and 5 mg (n=20) was performed. After being used for approximately 72 hours by patients with cancer, each patch was put in the plastic bag and stored at $4^{\circ}C$ until analysis. Fentanyl remaining in patches was extracted with 50 ml methanol, diluted with water, and counted twice in a $\gamma-Counter$ (expressed as CPM). Patches that originally contained 2.5 mg and 5 mg of fentanyl were shown to have $0.48{\sim}1.86\;mg\;(mean:\;1.03\;mg,\;41.16\%)\;and\;0.37{\sim}3.95\;mg\;(mean:\;2.37\;mg,\;47.33\%)$ after use, respectively. A wide interpatient variability was observed in the rate of fentanyl release from patches although the application period was standardized to 72 hours. Since a significant amount of drug remained in the discarded patches, it is highly recommended that patients dispose used ones under supervision to prevent abuse or misuse of the narcotic drug.

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Study on a Hedging Volatility Depending on Path Type of Underlying Asset Prices (기초자산의 추세 여부에 따른 헤지변동성의 결정에 관한 연구)

  • Koo, Jeongbon;Song, Junmo
    • The Korean Journal of Applied Statistics
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    • v.26 no.1
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    • pp.187-200
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    • 2013
  • In this paper, we deal with the problem of deciding a hedging volatility for ATM plain options when we hedge those options based on geometric Brownian motion. For this, we study the relation between hedging volatility and hedge profit&loss(P&L) as well as perform Monte Carlo simulations and real data analysis to examine how differently hedge P&L is affected by the selection of hedging volatility. In conclusion, using a relatively low hedging volatility is found to be more favorable for hedge P&L when underlying asset prices are expected to be range bound; however, a relatively high volatility is found to be favorable when underlying asset prices are expected to move on a trend.

Pharmacokinetics and Tissue Distribution of UTI in the Rat (랫드에서의 UTI의 약물동태학 및 조직 분포)

  • 정요찬;윤효인;조명행;박병권;발일현;김복환;송동호
    • Biomolecules & Therapeutics
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    • v.4 no.3
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    • pp.265-270
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    • 1996
  • The purpose of this study was to determine pharmacokinetic parameters and tissue distribution patters of urinary trypsin inhibitor(UTI) in Sprague-Dawley rats. $Na^{125}$I was conjugated to UTI to make $^{125}I-UTI$ and the concentrations were determined by $\gamma$-counter. With the aid of nonlinear least-square regression analysis for i.v bolus injection of 1,000 unit UTI including $^{125}I-UTI$, the temporal concentration curves were best fitted by 2-compartment open model. The distribution phase half-life was 0.39$\pm$0.02 hours whereas the elimination half-life was 12.99$\pm$1.05 hours in male rats. The volume of distribution and total body clearance in male rats were 0.28$\pm$0.01 1/kg and 83.16$\pm$1.15 ml/kg/h, respectively. We could not find any difference of pharmacokinetic parameters of UTI between male and female rats. UTI were distributed widely in rat organs. In both male and female rats, the kidney was the highest distributed organ. Amount of UTI in 24 hour cumulative urine in male rats was 36.22$\pm$8.74% and that in 48 hours was 43.32$\pm$10.55%. Excretion via feces was very scanty, with the 24 hours cumulative amount being only 2.76$\pm$0.97%. This data suggest the main excretion route of UTI is urine.

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Bone Density Spatial Distribution of Radiation Dose Measurement (양방사선 골밀도 측정 장치의 공간산란선량분포측정)

  • Kim, Seon-Chil;Won, Do-Yeon;Park, Chang-Hee;Dong, Kyung-Rae
    • Korean Journal of Digital Imaging in Medicine
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    • v.13 no.2
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    • pp.59-62
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    • 2011
  • In this experiment, how DEXA(Dual-energy X-ray Absorptiometry) bone mineral density was measured using the equipment. In order to maintain the same measurement conditions, bone mineral density measurements of 10 cm thick phantom, with an actual patient at a point when examining the same conditions(100 kVp, 1 mA) and then out to the five doses of radiation and its average was calculated by dividing measured. X-ray dose rate measured at the Research Institute, Sword of the gamma survey meters calibrated MEDCOM Ltd. (Inspector GM counter tube) was used, calibration factor is 1.15. On a horizontal plane around the patient, depending on the distance was significantly reduced dose rate. In addition, orientation $0^{\circ}$ head end was higher in the direction of the highest dose rate, $0^{\circ}$ $180^{\circ}$ direction from the direction towards the higher dose rate reduced to some extent in the direction of all the $120^{\circ}$ were able to identify.

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Determination of Arsenic in Korean human liver and manganese, copper in Vitamin prepartions by neutron action analysis (중성자(中性子) 방사화(放射化) 분석법(分析法)에 의(依)한 한국인(韓國人) 간장중(肝臟中)의 비소(砒素) 및 Vitamin제제중(製劑中)의 금속(金屬)(CU, Mn)의 정량(定量))

  • Oh, Soo-Chang
    • Journal of Pharmaceutical Investigation
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    • v.4 no.4
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    • pp.17-25
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    • 1974
  • 1. Neutron acivation analysis of arsenic contained in Korean human liver was studied in the view point of forensic chemistry, using 12 corpses. A sample of 1g was irradiated for 30 mins. in a neutron flux of $1.2{\times}10^{12}n/cm^2/sec$, followed by nitric-sulfuric acid digestion and then by Gutzeit separation. Radio activity was detected by it's scintillation counter. The arsenic content in the liver was found to be $0.01{\mu}g/g$ to $0.15{\mu}g/g$. 2. A rapid and convenient method for the radiochemical determination of minerals by neutron activation analysis was established. After neutron irradiation to the standard soln. of Cu and Mn in pneumatic tube (neutron flux : $1.2{\times}10^{12}n/cm^2/sec$), Cu and Mn were determined by estimating the ratio of the widths under energy peak area in ${\gamma}-ray-spectrogram$. When the standard soln. of Mn and Cu is irradiated for 15 mins. to 18 hrs., recovery test shows that the relative errors are 5.1% and 4.5% for copper and manganese, respectively.

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A Study on the Electronic Properties of LB Thin Films (LB박막의 전자이동 특성에 관한 연구)

  • Song, Jin-Won;Choi, Young-Il;Lee, Kyung-Sup
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2002.08a
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    • pp.101-104
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    • 2002
  • Abstract We give pressure stimulation into organic thin films and then manufacture a device under the accumulation condition that the state surface pressure is 10[mN/m]. In processing of a device manufacture, we can see the process is good from the change of a surface pressure for organic thin films and transfer ratio of area per molecule. The structure of manufactured device is Au/Poly-${\gamma}$ Benzyl $_D$-Glutamate/Al; the number of accumulated layers is 1, 3, 5 and 7. Also, we then examined of the MIM device by means of I-V. The I-V characteristic of the device is measured from 0 to +2[V]. We determined electrochemical measurement by using cyclic voltammetry with a three-electrode system. LB film accumulated by monolayer on an ITO. In the cyclicvoltammetry, An Ag/AgCl reference electrode, a platinum wire counter electrode and LB film-coated ITO working electrode measured in $LiBF_4$ solution, stable up to 0.9V vs. Ag/AgCl.

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Development of Dual FDG Auto Synthesis Module (듀얼 FDG 자동합성장치 개발)

  • Jeong, Cheol-Ki;Lee, Goung-Jin;Hur, Min-Goo;Jang, Hong-Suk;Min, Young-Don
    • Journal of Radiation Industry
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    • v.5 no.4
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    • pp.313-316
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    • 2011
  • [$^{18}F$]FDG (2-[$^{18}F$] Fluoro-2-deoxy-D-Glucose), which is required Automated Synthetic Module for production, is most often used Radiopharmaceuticals in nuclear medicine. In this study, an Automated Synthesis Module was developed to produce FDG in two consecutive time when F-18 feds continuously by modifying a domestic FDG Automated Synthetic Module on structural geometry and control system. The results were showed that the Average Synthesis Yields on the developed Automated Synthetic Module were $45{\pm}3%$ (n=20), $50{\pm}3%$ (n=20) respectively. The Quality Control results, such as Radio TLC, Radiochemical purity, Gamma-counter, pH, LAL Test, Micro bacteria test, showed in same level with domestic [$^{18}F$]FDG Auto-Synthetic modules. Therefore, if some features were improved by considering the components life time and appearance, commercial sales can be expected because of low price and easy maintenance compared with foreign products.

Evaluation of the Usefulness for VMAT of multiple brain metastasis using jaw tracking (Jaw tracking을 이용한 다발성 뇌 전이의 용적세기조절회전치료에 대한 유용성 평가)

  • Kim, Tae Won;Yoo, Soon Mi;Jeon, Soo Dong;Yoon, In Ha;Back, Geum Mun
    • The Journal of Korean Society for Radiation Therapy
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    • v.30 no.1_2
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    • pp.73-81
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    • 2018
  • Purpose : The aims of this study were to compare and assess the effectiveness of Volumetric Modulated Arc Therapy(VMAT) using jaw tracking(JT) and fixed jaw(FJ) in radiation therapy of multiple brain metastasis. Methode and material : Among the patients with Multiple Brain Metastasis treated with jaw tracking, 10 patients with more than 6 tumors and with the size of radiation field $14{\times}14cm^2$ or more were included. Each Treatment plans with jaw tracking(JT) and fixed jaw(FJ) was established with Eclipse (Ver. 13.6 Varian, USA). Gamma Index (3 mm, 3 % confidence interval - 95 %) and maximum dose difference were measured with an electronic portal imaging device(EPID). The $D_{max}$ and $D_{mean}$ of Organ At Risk(OAR) were assessed and compared, and the Conformity Index(CI) and Homogeneity Index(HI) were evaluated. Result : Evaluating jaw tracking(JT) and fixed jaw(FJ) outcomes, in all cases, Gamma Index met the permissible standard of 3 mm, 3 % confidence intervals of 95 %. The maximum dose difference value from the areas with leaf end transmission was measured at a maximum of 98.4 % and an average of 43.6 % in clockwise(CW), and 67.9 % and 41.0 % for each in Counter-Clockwise(CCW). With jaw tracking, the maximum value of $D_{max}$ for each normal organ in OAR decreased in 15.36 %~74.59 % with the average value decreasing in 2.84 %~39.80 %. The maximum value of $D_{mean}$ in OAR decreased in 27.90 %~65.23 %, with the average value decreasing in 7.70 %~41.71 %. No change has been found in Conformity Index and Homogeneity Index values. Conclusion : When Jaw tracking is used in treating patients with multiple brain metastasis with VMAT, the unnecessary exposure due to leakage and transmission of radiation in unspecified areas was reduced, without affecting the dose distribution of the planning target volume(PTV), and the availability of radiation therapy with lower doses in normal organs is expected.

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