• Title/Summary/Keyword: 베타율

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Analysis of Counting Rate according to Presence or Absence of Detector's Protector in Beta-rays Measurement using Geiger-Muller Counter (Geiger-Muller 계수관을 이용한 베타선측정에서 디텍터 보호유무에 따른 계수율 분석)

  • Jang, Ji-Yong;Jeong, Moon-Taeg;Song, Jong-Nam;Ha, Jae-Jun;Han, Jae-Bok
    • Journal of the Korean Society of Radiology
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    • v.12 no.1
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    • pp.31-37
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    • 2018
  • In the surface contamination test using the end-window Geiger-Muller type counter, the wrap is used as a method for protecting the detector exposed to the outside in order to measure the beta-rays. We analyze the effect of this method on the measurement rate and the correction factor, and wanted to make it clear to radiation workers that excessive use of the wrap can affect the measured value of the beta-rays. The experimental method was to compare and analyze the change of the beta-rays measurement counting rate and the calibration factor according to the wrap thickness using the beta-rays with different energy of 3 KBq, 1.5 KBq and 0.3 KBq. The subjects of this study were the end-window Geiger-Muller type counter which were held at the calibration center certified by Korea Laboratory Accreditation Scheme (KOLAS) in March 2012, Cl-36 (Chlorine) and Sr-90 (Strontium) were used as the source of beta radiation. The measurement counting rate decreased with increasing wrap thickness, and the calibration factor increased with increasing wrap thickness. Since the changes of the measurement counting rate and the calibration factors can reduce the accuracy of the instrument readings, but also have a significant impact on detector contamination and damage, so there is a need to find out what thickness of wrap is most effective. If we using a wraps with thickness that show a low rate of change of the measurement counting rate and the calibration factor, it will protect the detector and minimize the effect on the measured value of the beta-rays.

Intercomparison of the KAERI Reference Photon and Beta Radiation Measurements (한국원자력연구소 기준 광자 및 베타선장 측정의 국제상호비교)

  • Chang, Si-Yeong;Kim, Bong-Hwan;Kim, Jang-Lyul;McDonald, J.C.;Murphy, M.K.
    • Journal of Radiation Protection and Research
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    • v.21 no.4
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    • pp.255-262
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    • 1996
  • This paper describes the results of intercomparison measurements of KAERI reference photon and beta radiation fields between the KAERI and the PNNL(Pacific Northwest National Laboratory), recently performed at KAERI radiation calibration and dosimetry laboratory on the basis of the ANSI N13.11 criteria for personal dosimeter performance test. Each laboratory used her own radiation detectors or measurement devices traceable to her national primary standard in measuring the exposure rates for photon fields, the absorbed dose rates for beta radiation fields. The agreements in reference radiation measurements between two laboratories were found to be less than ${\pm}2.0%$ for photon fields, ${\pm}1.0%$ for beta radiation fields. Therefore, it could be concluded that KAERI reference radiation fields comply well with the international standard and thus can further serve as a national basis for the researches and developments in radiation protection dosimetry in Korea.

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True Retention and β-Carotene Contents in 22 Blanched Vegetables (데치기(Blanching)로 조리된 22가지 채소류의 베타카로틴 함량의 변화와 영양소 보존율(True Retention))

  • Hwang, Keum-Hee;Shin, Jung-Ah;Lee, Ki-Teak
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.45 no.7
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    • pp.990-995
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    • 2016
  • In the present study, reversed-phase HPLC was utilized to quantify the ${\beta}$-carotene content of 22 kinds of raw and blanched vegetables consumed in Korea. In addition, true retention (TR) of ${\beta}$-carotene in samples was obtained. For quantification of ${\beta}$-carotene, external standard curve was obtained with limit of detection and limit of quantitation. The ${\beta}$-carotene contents in 22 raw vegetables ranged from 6.29 (bellflower root) to $7,050.73{\mu}g/100g$ (spinach, field culture). After blanching, ${\beta}$-carotene contents of 13 vegetables increased up to 103.05% while nine vegetables resulted in reduced content, ranging from -2.17 to -29.16%. However, even though increased ${\beta}$-carotene content was observed after blanching, TR of some vegetables was lower than 100% due to their weight reduction. The highest TR of ${\beta}$-carotene was found from blanched cabbage (164.46%) while the lowest TR was found from Turcz (Gomchwi) at 59.35%. TR is an effective method to evaluate retention of nutrients in cooked foods, considering changes of nutrient content and weight.

Effect on Pancreatic Beta Cells and Nerve Cells by Low LET X-ray (Low LET X-ray가 췌장 ${\beta}$ 세포와 신경세포에 미치는 효과)

  • Park, Kwang-Hun;Kim, Kgu-Hwan
    • Journal of radiological science and technology
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    • v.37 no.1
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    • pp.21-28
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    • 2014
  • Cultured pancreatic beta cells and nerve cells, it is given normal condition of 10% FBS (fetal bovine serum), 11.1 mM glucose and hyperglycemia codition of 1% FBS, 30 mM glucose. For low LET X-ray irradiated with 0.5 Gy/hr dose-rate(total dose: 0.5 to 5 Gy). Survival rates were measured by MTT assay. When non irradiated, differentiated in the pancreatic beta cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a small reduction. However increasing the total dose of X-ray, the survival rate of normal conditions decreased slightly compared to the survival rate of hyperglycemia conditions, the synergistic effect was drastically reduced. When non irradiated, undifferentiated in the nerve cells experiment is hyperglycemia conditions survival rate compared to normal conditions survival rate seemed a large reduction. As the cumulative dose of X-ray normal conditions and hyperglycemia were all relatively rapid cell death. But the rate of decreased survivals by almost parallel to the reduction proceed and it didn't show synergistic effect.

Changes in β-Carotene, Vitamin E, and Folate Compositions and Retention Rates of Pepper and Paprika by Color and Cooking Method (고추와 파프리카의 색과 조리방법의 차이에 따른 베타카로틴, 비타민 E, 엽산의 함량과 잔존율)

  • Kim, Hyeon Young;Kim, Honggyun;Chun, Jiyeon;Chung, Heajung
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.46 no.6
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    • pp.713-720
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    • 2017
  • ${\beta}-Carotene$, vitamin E, and folate contents according to color and species of Capsicum annuum were investigated. In addition, four C. annuum species were cooked by using different methods (boiling, pan-cooking, pan-frying, deep-frying, steaming, roasting, and microwaving), and retention rates of ${\beta}-Carotene$, vitamin E, and folate affected by color and species were evaluated. Weight loss was observed in all paprika and pepper species using all cooking methods. ${\beta}-Carotene$ and folate contents of C. annuum samples were significantly different by color, species, and cooking method (P<0.05), whereas vitamin E contents were not significantly affected by species. ${\beta}-Carotene$, vitamin E, and folate contents (mg/100 g) of raw C. annuum showed ranges of 95.4 (green pepper)~2,441.1 (red pepper), 0.7 (green paprika)~4.2 (red paprika), and 6.2 (green pepper)~148.7 (red pepper). As a result, the highest ${\beta}-Carotene$, vitamin E, and folate contents were detected in deep fried red pepper, roasted red pepper, and boiled red pepper, respectively, among the cooked samples. Retention rates of C. annuum varied by cooking method, resulting in ranges of 77.3% (boiled red pepper)~356.4% (roasted green pepper) for ${\beta}-Carotene$, 2.0% (microwaved red pepper)~789.3% (deep-fried green paprika) for vitamin E, and 20.9% (microwaved red pepper)~445.1% (steamed green pepper) for folate. Over 75% retention rates were observed for ${\beta}-Carotene$, vitamin E, and folate in all samples except for red pepper. However, in red pepper, vitamin E and folate retentions were remarkably lowered by deep frying and micro-waving, resulting in rates of 2.0~32.1%. This study provides information on effective cooking methods for vitamin retention in C. annuum depending on color and species.

Measurement of Absorbed Dose at the Tissue Surface from a Plain $^{90}Sr+^{90}Y$ Beta Sources (조직 표면에서의 베타선 흡수선량 측정)

  • Hah, Suck-Ho;Kim, Jeong-Mook;Yook, Chong-Chul
    • Journal of Radiation Protection and Research
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    • v.16 no.2
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    • pp.17-26
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    • 1991
  • Beta ray $(^{90}Sr+^{90}Y)$ absorbed dose at tissue surface was measured from the distance of 30cm by use of extrapolation chamber. In the measurement, following factors were considered: effective area of collecting electrode, polarity effect, ion recombination and window attenuation. The measured absorbed dose rate at tissue surface was $1.493{\mu}Gy/sec$ with ${\pm}2.9%$.

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A Theoretical Investigation of Roll-Off Cleanliness for Hydraulic System and Application to a Tractor (유압시스템 롤-오프 청정도의 이론적 고찰 및 트랙터에의 응용)

  • 이재천
    • Transactions of the Korean Society of Automotive Engineers
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    • v.8 no.5
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    • pp.207-215
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    • 2000
  • This study theoretically investigated the roll-off cleanliness operation to eliminate the built-in contaminants which are primarily the result of manufacturing and assembly procedures first. A rigorous analytical examination of the cleaning process associated with hydraulic systems was performed by developing the general filtration process equations. The sloughing process by which built-in contaminant is entrained in the system fluid was examined during the development of a general analytical expression for sloughing rate. This sloughing rate expression in conjunction with the filtration process equations have lead to a relationship rate expression in conjunction with the filtration process equations have lead to a relationship which describes the flushing and clean-up operation for the hydraulic systems. The effects of the primary roll-off cleanliness factors was discussed and illustrated on the figures. Then, the analytical results was shown to be usefully applied into the design of roll-off flushing equipment for the hydraulic system of a tractor.

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우유내 체세포수 감소를 위한 사료 첨가제(하)

  • Jeong, Ha-Yeon
    • Feed Journal
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    • v.2 no.5
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    • pp.100-103
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    • 2004
  • 사료내 비타민E의 수준은 유방염 발생과 음의 상관관계가 있다. 또한, 비타민 A와 베타카로틴의 결핍시 질병에 대한 저항성에 영향을 주어 유방염 발생율의 증가를 가져온 것으로 알려져 있다. (중략)

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Effect of Dietary Glycine Betaine on Pork Qualities During Storage (Glycine betaine의 급여가 돈육의 품질에 미치는 영향)

  • Park, G.B.;Hur, S.J.;Yang, H.S.;Lee, J.I.;Kwck, S.J.;Lee, J.D.;Huh, N.E.;Kim, J.S.;Joo, S.T.
    • Journal of Animal Science and Technology
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    • v.46 no.5
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    • pp.821-832
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    • 2004
  • A total of 80 pigs were used to investigate the effect of dietary glycine betaine(N,N,N-trimethylglycine) on pork quality during cold storage. About 70 kg pigs were randomly a1loted into one of four experimental diet groups(0%, 0.2%, 0.4% and 0.6% glycine betaine). Pigs were slaughtered at approximately 110 kg live weight, and pH, color(CIE $L^* a^* b^*$), shear force, sarcomere length, lipid oxidation and composition of fatty acid were measured in pork loin for 13 days of cold storage. The concentration of glycine betaine in pork loin was significantly increased(P<0.05) with increasing of glycine betaine level in diet. Pork loins from dietary betaine groups showed significantly higher muscle pH and lower CIE $b^*$ values compared to control group after 13 days of storage. There were significant differences in shear force values among pork loins from diet groups at 24 hrs postmortem. However, pork loins from control diet showed longer sarcomere length than those of dietary betaine groups. Dietary glycine betaine increased the ratio of saturated fatty acids and decreased unsaturated fatty acids in pork loins. Especially the ratios of linoleic and myristic acid were decreased with increasing dietary betaine level. However, dietary glycine betaine did not affect lipid oxidation (TSARS) and sensory evaluation during cold storage.

Effects of Paprika Extract and Its Components on Cell Death and Expression of p53 and GADD45 Genes in Ultraviolet B- Exposed HaCaT Cells (UVB를 조사한 HaCaT 세포의 세포사멸과 p53 및 GADD45 유전자 발현에 대한 파프리카 추출물 및 성분들의 효과)

  • Ha, Se-Eun;Kim, Hyung-Do;Kang, Jea-Ran;Park, Jong-Kun
    • Journal of Life Science
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    • v.21 no.5
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    • pp.753-760
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    • 2011
  • In the present study, the effects of paprika extract and its components including vitamin C, lycopene and beta-carotene on cell death in ultraviolet B (UVB)-exposed HaCaT cells were investigated. The cell viability upon treatment for 24 hr with either paprika extract or vitamin C alone was similar to or greater than that of the untreated control. However, the viability of the cells treated with lycopene or beta-carotene decreased to about 20% of that in the untreated control. When UVB-exposed cells were post-incubated for 24 hr in medium containing paprika extract or vitamin C, cell viability increased in a concentration dependent manner as compared to those post-incubated in a normal growth medium. In contrast, post-incubation of UVB-exposed cells with lycopene or beta-carotene decreased cell viability in a concentration dependent manner as compared to those post-incubated in a normal growth medium. The nuclear fragmentation analysis showed that paprika extract or vitamin C decreases UVB-induced apoptosis. The apoptotic nuclear fragmentation resulting from UVB exposure was also protected by the paprika extract or vitamin C post-incubation. However, the UVB-induced apoptotic nuclear fragmentation of the cells treated with lycopene or beta-carotene increased in a concentration dependent manner. Western blot analysis showed that either paprika extract or vitamin C treatment alone did not significantly change the level of p53 and GADD45 protein. Interestingly, post-incubation of UVB-exposed cells with paprika extract or vitamin C decreased the p53 and GADD45 protein level as compared to those post-incubated in a normal growth medium. In contrast, incubation of UVB-exposed or non-irradiated cells with lycopene or beta-carotene increased the p53 and GADD45 protein levels in a concentration dependent manner as compared to those incubated in a normal growth medium. All these results suggest that paprika extract and vitamin C help the survival of the UVB-exposed cells, while lycopene and beta-carotene potentiate the apoptotic death of UVB-exposed cells, in accordance with the respective changes in p53 and GADD45 protein levels.