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        검색결과 17

        1.
        2023.11 구독 인증기관·개인회원 무료
        The Korea Research Institute of Standards and Science has developed certified reference materials (concrete, soil, and metal radioactive liquid) for measuring gamma-emitting radionuclides to improve and maintain the quality assurance and quality control of the radioactivity measurement in decommissioning nuclear power plants. The raw materials that make up each CRM were mixed in an appropriate ratio with radionuclides. For certification and homogeneity assessment, 10 bottles were randomly selected, two sub-samples were collected from each bottle, and radionuclides were measured via HPGe gamma spectrometry. The results of the homogeneity tests using a one-way analysis of variance on the radionuclides in the CRMs fulfilled the requirements of ISO Guide 35. Coincidence summing and self-absorption correction were performed on measurement results by introducing the Monte Carlo efficiency transfer code and Monte Carlo N-Particle transport code. In concrete analysis, the reference values for five radionuclides (60Co, 241Am, 134Cs, and 137Cs) in the CRM were in the range of 15-40 Bq/kg, and the expanded uncertainty was within 10% (k = 2). In soil analysis, the reference values for the 137Cs and 60Co were 118.7 and 124.4 Bq/kg, and the expanded uncertainty was within 10% (k = 2). In metal radioactive liquid analysis, the reference values for 134Cs, 137Cs and 60Co in the CRM were in the range of 200-270 Bq/kg, and the expanded uncertainty was within 7% (k = 2).
        2.
        2022.05 구독 인증기관·개인회원 무료
        This study is about the production of radiation sources of simulated concrete and soil reference materials to verify the validity of the quality establishment and measurement of the detector (HPGe) of the radioactive soil and concrete waste classification system, which is being developed to quickly and accurately classify nuclear decommissioning waste. Specific activity of gamma nucleus among radioactive wastes is evaluated using gamma spectroscopy. At this time, in order to verify the validity and reliability of measuring equipment, it shall be a standardized substance of the same medium as nuclear decommissioning waste (chemical ingredients, particles, density, etc.) in order to correct the energy and efficiency of gamma nuclide analysis equipment. The CRM used for the detector’s energy correction used a 1 L Marinelli beaker standard correctional radiation source consisting of 10 radioactive isotopes. In order to correct efficiency, in accordance with the production and certification process of the Korea Standards and Research Institute, it has produced artificial simulated radioactive concrete similar to nuclear decommissioning waste (30% for cement, 60% for regulation and 10% for bentonite). The radioactive homogeneity of the simulated concrete reference materials was evaluated using dispersion analysis (ANOVA) in accordance with ISO Guide 35, while 137Cs and 60Co of concrete reference materials were able to obtain homogeneous measurements both in and between bottles. The self-absorption rate of the simulated concrete reference material was determined by the MCNP computer simulation measurement method, and the self-absorption correction coefficients of 137Cs and 60Co were assessed at 0.995 and 0.996, respectively, and the standard value for the radiation of the simulated concrete reference material was calculated on the weighted average of the measurements of 20 samples. The uncertainty about the reference value was calculated by combining measurement uncertainty (Type B evaluation), bottle to bottle standard deviation, and uncertainty within bottle by modifying the formula suggested in ISO Guide 35. The concentration of 137Cs and 60Co of reference materials was divided into high-speed measurement mode and precision measurement mode in consideration of the self-disposal standard. The reference value and uncertainty of expansion among reference materials for high-speed measurement mode were rated at 1,032.7 ± 64.0 Bq·kg−1and 1,083.7 Bq·kg−1, respectively. The standard value and expansion uncertainty for 137Cs and 60Co among reference materials for precision measurement mode were rated at 113.7 ± 10.0 Bq·kg−1 and 122.3 ± 10.3 Bq·kg−1, respectively.
        3.
        2022.05 구독 인증기관·개인회원 무료
        As Kori-1 permanently shut down in Korea, it is expected that a large amount of radioactive waste will be generated during decommissioning of nuclear power plants. Radioactive concrete waste is contaminated up to depth of 100 mm with radionuclides such as 137Cs and 60Co. The radioactive waste should be accurately classified to reduce the cost of disposing of radioactive waste. Therefore, the specific radioactivity of waste must be precisely evaluated by gamma-ray measurements emitted from the radionuclides. In general, the effectiveness of the radioactivity measurement and process is confirmed using certified reference material (CRM) composed of water or agar. However, the decommissioning waste differs from this CRM in apparent density and chemical elements, so the specific radioactivity is underestimated or overestimated. Therefore, reference material composed of the same apparent density and chemical elements as the sample is required to improve the quality of radioactivity measurement. The purpose of this study is to develop a concrete reference material for the nuclear decommissioning waste. The concrete reference material composed of SiO2, CaO, and Al2O3 were manufactured in compliance with ISO Guide 35. 10 bottles were randomly selected for homogeneity test, and 2 samples for analysis were taken from each bottle. The specific radioactivity was measured using an HPGe detector with an efficiency of 30%. The results of the homogeneity test of 137Cs and 60Co satisfied the requirements of ISO Guide 35. Coincidence summing and selfabsorption effects were corrected using the Monte Carlo efficiency transfer code and Monte Carlo NParticle transport code. The reference values of 137Cs and 60Co in the concrete reference material were evaluated in the range of 1,000–1,100 Bq·kg−1 and extended uncertainty was around 7%.
        4.
        2015.12 구독 인증기관 무료, 개인회원 유료
        Hunter's color value “a” in dried-persimmon of table and full ripe fruit was higher than that in unripe fruit. In case of soluble solid content, full ripe fruit was 50o Brix, the highest degree, while unripe fruit was 40o Brix, the lowest degree. PPO activation of unripe fruit was 4.7, which was higher than table-ripe fruit (0.7) and full ripe (1.0). Polyphenol oxidase activation remained even while drying, but there was no difference in PPO activation degree as drying period increased. Total phenol content of unripe fruit was 101.4, which was higher than table-ripe fruit (57.5) and full ripe fruit (67.4). Total phenol content level increased as drying period increased, which was based on fresh weight. Hardness of unripe and table ripe fruit continued to decrease until three weeks during softening. After that, hardness was high and it started drying. However, in full ripe fruit, hardness increased after two weeks and softening was fast during the drying period, and its weight reduction rate was lower than that of unripe and table ripe fruit.
        3,000원
        5.
        2014.03 구독 인증기관 무료, 개인회원 유료
        김치의 숙성과정 중 일어날 수 있는 식품위생상 이물질의 오염방지를 위하여 혼입시험을 고안하여 이를 모니터링 하였다. 먼저, 시험군은 소금으로 절이고 양념으로 버무린 김치였고, 대조구는 소금에 절이지 않았거나 양념을 하지 않은 배추를 선택하였다. 오염원으로는 배추와 색깔이 유사한 청개구리를 선택하였다. 그 결과, 염분이 첨가되지 않은 대조구에서는 오염원이 10일 이상 생존하였으나 염분이 첨가된 시험구의 이물질은 5일 이상 생존할 수 없었다. 김치제조 중에 혼입된 생물학적 이물질은 대개 5일정도 생존하므로 소비자에 의하여 살아있는 상태로 발견된 사실은 제조 후에 혼입되었다고 추정할 수 있다.
        3,000원
        6.
        2013.12 구독 인증기관 무료, 개인회원 유료
        We studied antioxidant activity and inhibitory effect of α-glucosidase from aqueous, ethanolic and methanolic fractions of Galla rhois. In FRAP and ORAC assay for measuring antioxidant activity, we confirmed that Galla rhois extracts had strong antioxidant activity and ethanolic and methanolic extracts were relatively stronger than aqueous extract. We used trolox as a positive control. In order to measure the inhibitory effect of α-glucosidase, we compared acarbose and Galla rhois extracts. As a result of α-glucosidase inhibitory assay, aqueous, ethanolic and methanolic extracts of Galla rhois showed high inhibitory activitity and ethanolic and methanolic extracts were relatively stronger than aqueous extract. The 50% inhibitory concentrations (IC50s) of acarbose, aqueous, ethanolic and methanolic fractions were 0.45 mM, 0.53 μg/mL, 0.415 μg/mL and 0.37 μg/mL, respectively. These results suggest that Galla rhois extracts can be a clinically useful anti-diabetic ingredient, indicating that it needs to be fractionated and isolated and should be further investigated.
        4,000원
        7.
        2010.05 KCI 등재 구독 인증기관 무료, 개인회원 유료
        A fiber fraction (Aloe cellulose), the by-product obtained from Aloe vera gel processing was freeze dried and investigated for in vitro glucose/ bile acid retarding effects of powdered sample (100 mesh) comparing with commercial α-cellulose as a reference sample. We also examined the effectiveness of physiological functionality such as the antiobesity and anti-constipation on Sprague-Dawley (SD) rat. The Aloe cellulose powders during in vitro dialysis experiment for 2 hours exhibited the glucose and bile acid retarding index of 20.32-35.2% and 53.13-28.30%, respectively. Especially, freeze dried aloe cellulose showed the 2.5 and 1.2-6 times higher effect on in vitro glucose and bile acid retardation than those of α-cellulose. These relatively good retarding effects on glucose and bile acid diffusion suggest a potential of preventing from diabetes and arteriosclerosis of some extent. Also, the results from animal experiments on SD rats fed a high-fat diet for 4 weeks suggested that Aloe cellulose might be used as a novel dietary fiber showing an effective anti-obesity and anti-constipation effect.
        4,000원
        8.
        2019.06 KCI 등재 서비스 종료(열람 제한)
        Ultraviolet (UV) radiation is associated with the development of extrinsic skin aging. We performed in vivo assays in order to investigate the protective effect of a combination of grapefruit and rosemary extracts (cG&Re) on UVB-induced skin aging. The results indicated that cG&Re displayed elastase inhibitory activity in a dose-dependent manner. Topical application of cG&Re mitigated photo-aging related lesions such as skin erythema and thickening in photo-aged BALB/c mice dorsal skin, by preventing UVB-induced collagen degradation. Immunohistochemical analyses revealed that cG&Re stimulated SIRT-1 expression, and suppressed MMP-1 and IL-1β expression. It was observed that expression of MMP-1 and -13 mRNA was downregulated in the cG&Re-treated group. Furthermore, cG&Re treatment drastically suppressed protein expression of MMP-1 and regulated the phosphorylation of p-38 kinase. As expected, oral administration of cG&Re resulted in the same SIRT-1, MMP-1, and IL-1β expression patterns observed upon topical application of cG&Re in the UV-induced mice model. Overall, the current results demonstrated that cG&Re attenuated both the downregulation of MMP-1 expression and up-regulation of SIRT-1 expression, as well as decreased phosphorylation of MAPK in UVB-induced skin ageing mice model, suggesting that cG&Re might be used as an internal food ingredient for beauty-purposes as well as a functional food material.
        9.
        2017.09 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        This study was performed to investigate the correlation between anti-oxidant and anti-inflammatory activities in ripe and unripe fruits of three peach cultivars: Miwhang (MH), Kanoiwa hakuto (KH) and Cheonhong (CH). The unripe fruits had higher levels of total phenols and flavonoids contents than those in the ripe fruits of all the three cultivars. The unripe fruits of CH showed the highest levels of total phenols, flavonoids and antioxidant activities among the fruit samples analyzed. Nitric oxide inhibition values in RAW 264.7 cells for the unripe fruits of MH and KH were 30 and 29%, respectively. However, the inhibition was not observed in unripe CH and the ripe fruits of either cultivar. Total phenols and flavonoids contents showed high linear correlations with the anti-oxidant activities whereas the anti-inflammatory activity had low linear correlations with them.
        10.
        2014.02 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        국내산 곶감과 수입산 시판 곶감에 대한 이화학적 품질 특성 조사를 실시하였다. 수분함량은 22.78~61.64%이었으며, 중국산 곶감 2종의 수분함량은 각각 22.78, 28.20%로 국내산 보다 낮은 함량을 보였다. 지역별 곶감의 pH는 5.09∼5.99이었으며, 함안곶감이 5.99로 가장 높게 나타났다. 곶감의 당도는 종류별로 25.07∼42.93 °Brix이었으며, 지역별 곶감의 무게는 29.77∼77.95 g, 영동곶감이 29.77 g으로 무게가 가장 작았으며 산청 곶감은 77.95 g으로 가장 높게 나타났다. 시판 곶감제품 9종에 대한 색도 측정 결과, L값은 표면 부분이 곶감 종류별로 18.27∼66.20이었으며, a값은 -1.26∼10.70, 산청 덕산곶감은 10.70으로 가장 높게 나타났다. b값은 2.81∼25.25로 나타났으며, 청도 반건시와 산청 곶감이 각각 25.25와 21.98의 값으로 다소 높게 나타났다. 관능검사 결과 지역별 곶감의 외관은 청도 반건시가 3.77로 가장 높은 점수를 나타내었으며 완주 흑곶감이 1.39로 가장 낮게 나타났다. 전체적인 기호도는 중국산 No.2 곶감이 가장 높게 나타났으며, 다음으로 영동곶감, 하동곶감, 상주곶감이 각각 높게 나타났다. 이산화황 함량 분석 결과 국내산 지역별 곶감 7종과 중국산 곶감 2종 모두 10 mg/kg미만으로 불검출인 것으로 나타났다.
        11.
        2013.08 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        This study was done in order to investigate the bioconversion of ginsenoside, as well as the quality characteristics of fermented ginseng, by using lactic acid bacteria. Quality characteristics such as the thin layer chromatography(TLC) pattern, ginsenosides, total phenolic content, electron donating ability, and total sugar of fermenting ginseng and red ginseng were analyzed. The ginsenoside Rg2r, Rh2s and Rh2r of the fermented ginseng and red ginseng for 65 hours at a temperature of 37℃ were not detected. The ginsenoside Rg1 and Re contents have decreased, while the Rh1, Rg2s, Rd, Rg3r, and Rg3s have increased due to fermentation. The ginsenoside Rg3 of the fermented red ginseng has increased and the contents were 114.83∼131.68 μg/mL (control 104.56 μg/mL). The total phenolic content and electron donating ability of the red ginseng have totally decreased after 7 days of fermentation. The total phenolic contents of the fermented ginseng and red ginseng with different lactic acid bacteria did not show any tendency as different strains. The electron donating ability of the fermented ginseng has increased; however, the electron donating ability of the red ginseng has decreased. The total sugars of the fermented ginseng and red ginseng with different lactic acid bacteria have also decreased.
        12.
        2013.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        This study was conducted to investigate the change in quality attributes of fresh-cut potatoes with heat and browning inhibitor treatment (CW: dip in the cold water for 30 sec at 4℃, HW: dip in the water for 60 sec at 55℃, AA: dip in the 0.1% solution of ascorbic acid for 60 sec at 4℃, HA: dip in the 0.1% solution of ascorbic acid for 60 sec at 55℃) during storage at 5℃. During storage, fresh-cut potatoes treated with HA showed the lowest value in surface color. PPO and PAL activities of fresh-cut potatoes treated with HA were gradually increased during storage. Hardness, weight loss, soluble solids content and moisture content had no significant difference between the treatments. In sensory acceptance, fresh-cut potatoes treated for HA marked the best quality. Conclusively, heat and browning inhibitor treatment showed the positive effect on browning inhibition while maintaining the quality of fresh-cut potatoes.
        13.
        2013.04 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The purpose of this study was to evaluate the mortality rate, weight gain, and protein, lipid cholesterol, and total amino acid contents in processed-sulfur-diet chicken meat. Also investigated were the antioxidant activity and glutathione content of blood plasma. The mortality of the processed-sulfur-diet chickens was relatively reduced, and their weight increased compared to the normal-diet chickens. Although the glutathione content decreased in the processed-sulfur-diet chicken blood plasma, the antioxidant activity increased compared with the normal-diet chickens. Also, there was no difference in the total cholesterol contents of the blood, but the level of HDL cholesterol increased while that of LDL cholesterol decreased. Furthermore, there were no changes in the total amino acid and protein contents, but the fat content was significantly reduced. As no toxicity was found in the DT 40 cells in the MTT assay, it can be concluded that dietary sulfur in chicken feed can improve the quality of poultry products.
        14.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The antioxidant activity and whitening effect of the distilled water (DW) and ethanol extracts of the Prunus persica flower and calyx were studied. In the oxygen radical absorption capacity (ORAC) assay for antioxidant activity measurement, it was confirmed that the flower extract was stronger than the calyx extract, and that the ethanol extract was relatively stronger than the DW extract. To define the whitening effect, an experiment was conducted involving tyrosinase inhibitory assay and measurement of the melanin content of B16F10. As a result of the use of tyrosinase, the DW extract of calyx showed 53% inhibition as the highest activity. The melanin content inhibitory rates were defined as 57% for the ethanol flower extract and 63% of the ethanol calyx extract, based on a 10 μg/mL concentration. Based on these results, mixture with the whitening effect in the extract of P. persica and another compounds should be researched for development as a cosmetic ingredient.
        15.
        2012.12 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        In this study, we isolated microorganisms from dried persimmon in Sangju and obtained 15 strains of microorganisms as the basic research to prevent the quality changes during drying and storage of dried persimmon. Contaminated microorganisms were separated using seven species of medium. Viable cell counts of dried persimmon from Sangju was 5.18×102∼1.68×107 CFU/g. Green mold K2-1 accounted for the highest percentage in the contaminated dried persimmons and identified as a major causative microorganism. Light violet and creamy yeasts were the second largest contaminated microorganisms. Green mold K2-1 strain was identified as Penicillium sp. and fungus K-1 and K-3 were identified as Caldosporium sp. and Aspergillus sp.
        16.
        2012.10 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        The purpose of this study was to evaluate the anti-atopic-dermatitis effect of Angelica keiskei extract using a DNFB-induced animal model of atopic-dermatitis symptoms. A. keiskei was prepared via extraction with DW, 50% ethanol, and 100% ethanol in addition to fresh juice. All the extracts reduced the thickness levels of the ears and ear epidermis against swelling by DNFB inducement, especially in the aqueous-extract-treated group. The mRNA expressions of matrix metalloproteinases (MMPs), however, were not observed, which may indicate that Angelica keiskei extract alleviates the atopic-dermatitis symptoms in an MMP-independent manner. Finally, the level of the inflammatory cytokine IL-4 was inhibited only in the juice-treated group, although the IL-13 level was inhibited in the juice-, 50%-ethanol-extract-, and 100%-ethanol-extract-treated groups in a dose-dependent manner, and was not inhibited in the aqueous-extract-treated group. Taken together, these results suggest that Angelica keiskei extract has an inhibitory effect on atopic dermatitis, and may be a useful biomaterial for the development of cosmeceuticals.
        17.
        2012.06 KCI 등재 SCOPUS 서비스 종료(열람 제한)
        To investigate the anti-diabetic activity of ethanol and aqueous peel and seed extracts obtained from three different grape species (Cambell Early, MBA, and Kyoho), alpha-glucosidase inhibitory activity was examined. All extracts showed anti-diabetic activity, especially aqueous extract exhibited inhibitory effect above 70%. Thus, we used aqueous extract to check the potential hypoglycemic effects in a streptozotocin (STZ)-induced diabetic mice model. The results showed that the blood glucose level of STZ-induced diabetic mice decreased drastically after 3 hr when the aqueous extract of Cambell Early seed was treated to the mice model. The aqueous extract of Kyoho seed lessened blood glucose level by 60%. Together, these data indicate that extracts of grape peel and seed (aqueous or ethanol) may have potential in improving hypoglycemic effects in the diabetic symptoms, suggesting that further investigation on biomarker expressions should be rewarding.