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        검색결과 35

        1.
        2022.10 구독 인증기관·개인회원 무료
        There are generally two kinds of spent filter; one is spent filter media for mainly gaseous purification such as HEPA filter, the other is spent filter cartridge for liquid purification such as CVCS BRS cartridge type filter. The spent filter cartridge from liquid purification system has been storing in special shielding space in auxiliary building in NPPs since the beginning of 2006 according to the long term storage strategy for decaying short lived radionuclide and gaining the time for selecting practical treatment technology before final packaging. The spent filter cartridges generated Kori-1 reactor vary in their sizes as in length from 913 mm to 290 mm and range in radiation level from several hundred mSv per hour to below mSv per hour . It is high time that the spent filter cartridge is treated and packaged because LILW repository in Wolsung area is operating and Kori-1 reactor is scheduled to decommission. The spent filter cartridge is one of the wet solid wastes required of solidification. It is difficult for the spent filter cartridge to solidify because of their shape, structure, physical and chemical characteristics in addition to having high radiation level. NSSC notice defines that solidification of wet solid wastes include that solid material such as spent filter is encapsulated with cement, etc. as a form of macro-encapsulation. The radioactive waste acceptance criteria describes that non-homogeneous waste having above 74,000 Bq/g such as spent filter, dry active waste should be encapsulated with qualified material. Homogeneous waste such as spent resin, sludge, concentrated waste (liquid waste evaporator bottoms), etc. should be solidified complied with requirements except that spent filter which is allowed to encapsulate. It is needed to guide to the practice of these two requirements for spent filter. The sampling and test method is different between homogeneous solidification waste form and spent filter cartridge encapsulation waste form. For example, how core sample can be taken and how void space can be measured among spent filter cartridge in encapsulation waste form. The technical evaluation report for spent filter cartridge polymer encapsulation by US NRC has been reviewed and the technical position of US NRC was identified. As a result of review, improvement fields of waste acceptance criteria for spent filters are pointed out, and the technical position of US NRC for spent filter cartridge solidification is summarized. The recommendation on improvement directions for spent filter cartridge encapsulation is suggested.
        2.
        2022.05 구독 인증기관·개인회원 무료
        It has been discovered that the isosaccharinic acid (ISA) formed in a cellulose degradation leachate were capable of forming soluble complexes with thorium, uranium (IV) and plutonium. Since 1993, the ISA has received particular attention in the literature due to its ability to complex a range of radionuclides, potentially affecting the migration of radionuclides. ISA is formed as a result of interactions between cellulosic materials within the waste inventory and the alkalinity resulting from the use of cementitious materials in the construction of the repository. In an alkaline cementitious environment, cellulose degrades mainly via a peeling-off reaction. The main degradation product is ISA, a polyhydroxy type of ligand forming stable complexes with tri- and tetravalent radionuclides. ISA can have an adverse effect on the sorption of radionuclides to an extent which depends on its concentration in the cement pore water and potentially enhance their mobility. The concentration of ISA is governed by several factors such as cellulose loading, cement porosity, extent of cellulose degradation, etc. The sorption of ISA on cement, however, is the process which governs the concentration of ISA in the pore water. According to the experimental result from a literature, the ISA concentration in facilities with a cellulose loading of 5% is calculated to be of the order of 10−4 M. At this level, the effect of cellulose degradation products on radionuclide sorption is negligibly small. Recently in Korea, cellulous limits as waste acceptance criteria is studying and planning to prepare the detailed requirement for near surface radioactive waste disposal facilities. It is desirable to suggest consideration on cellulose disposal limits around the time that the regulatory body and concern organizations establish the cellulose disposal limits as follows. Firstly, identify the cellulose effect on the sorption of the nuclides as cementitious disposal environments such as affected nuclides, threshold value and contribution to radiological risks under domestic disposal environment. Secondly, make sure and consider the difference between lab-scale experimental conditions and probability occurring in real disposal conditions such as probability for generation and persistence of pH in cellulosic material disposal conditions and cellulosic material disposal methods. Finally, consider characterization of cellulosic material such as polymerization, contents of cellulose in law material and time of degradation process. As a result, desirable cellulose limits are to set up for both safety and economic aspect.
        13.
        2019.04 구독 인증기관·개인회원 무료
        본 조사지인 돌리네 습지보호지역은 경북 문경시 산북면 굴봉산 정상부에 위치하였으며, 물이 고이기 힘든 돌리네(doline) 지형에 형성된 희귀 습지이다. 뿐만 아니라 멸종위기종과 법적보호종이 분포하는 등 생물다양성 또한 매우 풍부한 것으로 평가되고 있다. 그러나 습지보호지역 주변으로 과수원 등 경작지가 형성되어 있어, 관리 및 보전을 위한 조사 및 대책이 필요하다. 따라서 본 조사에서는 습지보호지역의 체계적인 관리를 위하여 돌리네 습지의 곤충상을 조사하였다. 조사 방법에는 곤충의 다양한 습성과 서식환경을 고려하여, Searching, Sweeping, Pitfall trap, Bucket trap으로 총 4가지의 채집방법으로 조사를 실시하였다. 그 결과 총 11목 82과 188속 237종이 확인되었으며, 이중 딱정벌레목이 가장 많이 출현하였다. 특이사항으로 환경부지정종 51종(중복포함)이 조사되었으며, 그중 멸종위 기종 1종이 확인되었다. 본 연구를 통해 돌리네 습지보호지역의 곤충상을 파악하고 관리 및 보전에 대한 기초자료를 제공하고자 한다.
        16.
        2016.12 구독 인증기관 무료, 개인회원 유료
        이 연구는 고지방 및 고 콜레스테롤식이(HD)를 먹인 rat에서의 저지질혈증 및 항염증 효과에 영향을 미치는 카제인과 유당(cMRP) 그리고 락토바실러스 fermentum H9 (FcMRP)에 의해 발효된 cMRP에 의해 반응된 마일라드 반응 생성물의 효과를 조사했다. HD 식이를 실시한 rat은 정상적인 식이를 먹인 rat과 비교했을 때, 간의 트리글리세리드 농도가 유의적으로 증가했다. 이는 HD 그룹에 비해서 Simvastatin, L. fermentum H9(H9), cMRP, FcMRP의 처리기간의 총 트리글리세리드를 감소시킨 것으로 나타났다. 조직학적 분석에서 cMRP, F-cMRP 및 H9-를 먹인 rat에서 간과 대동맥 조직의 지질 축적이 감소한 것으로 관찰되었다. 또한, F-cMRP와 cMRP는 HD 그룹에서 내중막 두께를 감소시켰다. 게다가 H9, Cmrp, F-cMRP 처리는 ICAM-1 및 VCAM-1의 발현수준을 유의적으로 감소시켰지만, MCP-1의 발현 수준은 유의하게 감소시키지 못했다. 특히, ICAM-1과 VCAM-1의 발현은 HD 그룹에 비해 F-cMRP 그룹에서 유의적으로 감소했다. 이 연구 결과는 낙농 식품의 cMRP와 F-cMRP가 심혈관계 질환, 특히 죽상 동맥 경화증을 예방하거나 치료하는데 잠재적으로 사용될 수 있음을 시사한다.
        4,000원
        18.
        2015.06 구독 인증기관 무료, 개인회원 유료
        The Maillard reaction is a complex reaction that occurs between carbonyl and amine groups during food pro-cessing and storage. In addition, it produces a large number of Maillard reaction products (MRPs), which have an importantrole in determining food characteristics including aroma, color, flavor, and texture. Importantly, recent studies have beenconducted that the Maillard reaction products and their ferments with lactic acid bacteria (LAB) induced specific biologicalcharacteristics including antimicrobial, antioxidative, and antihypertensive activities as well as improved their physiologicalfeatures such as the heat stability and emulsifying properties. Therefore, we described on new insights for enhanced physi-ologic and biologic functions of MRPs through LAB fermentation.
        4,000원
        19.
        2012.06 구독 인증기관·개인회원 무료
        Hematopoietic stem cells (HSCs) are the self‐renewing, multipotent progenitors that give rise to all types of mature blood cells. The hallmark properties of HSCs are the ability to balance self‐renewal versus differentiation cell fate decisions to provide sufficient primitive cells to sustain haematopoiesis, while generating more mature cells with specialized capacities. In the present experiment, we optimized the techniques for isolation and identification of hematopoietic stem cells from cow peripheral blood. The objective of this study was to optimize the more accurate methodology for separation of mononuclear cells (MNCs) from peripheral blood and identification of HSCs by using a specific cell surface marker i.e. CD34. A total 10 peripheral blood samples were collected from Holstein dairy cows from jugular vein. We used Ficoll 400 in different concentrations from 1 to 12% and Ficollpaque Plus (1.077 g/ml) at different centrifugation speed and time. After Giemsa staining, we found more than 98% recovery of monocytes with Ficollpaque Plus (1.077 g/ml). It was demonstrated that Ficollpaque Plus (1.077 g/ml) and centrifugation at 400xg for 30 min is the best method for separation of MNCs from bovine peripheral blood. Separated MNCs were immediately subjected for magnetic activated cell sorting (MACS) by using CD34 microbead kit. HSCs (CD34+ cells) recovery was 0.307% of peripheral blood. Peripheral blood MNCs and CD34+ cells were morphologically characterized by Giemsa staining. CD34+ cells were also confirmed by immunochemistry using FITC conjugated CD34 antibodies. HSCs were also confirmed by progenitor assay including burst forming unit‐erythroid (BFU‐E), colony forming cells‐ granulocyte (CFC‐G), colony forming cells‐ macrophage (CFC‐M), colony forming cells‐ granulocyte macrophage (CFU‐GM) and colony forming cells‐ granulocyte erythroid macrophage monocyte (CFCGEMM) on Methocult 4435.
        20.
        2011.05 구독 인증기관·개인회원 무료
        Two species entomopathogenic fungi most widely used and valued in traditional Asian medical practice are Ophiocordyceps sinensis (formely Cordyceps sinensis) and Cordyceps militaris. Although O. sinensis may be the more famous and expensive fungus, it is also comparatively rare and cannot be grown or made to fruit readily in culture whereas C. militaris occurs worldwide, can be easily cultured, and is the easist of all Cordyceps species to fruit in culture. There is a well establihed cottage industry in Korea to produce C. militaris as a dietary supplement or even as a culinary ingredient used to promote improved health. Most of the Korean farmers raising C. militaris obtain fruiting bodies from silkworms that are injected with suspensions of hyphal bodies grown in liquid cultures. This study seeks to facilitate and to simplify the injection process used to produced this fungus by finding a simple cullture medium on which abundant supplies of the Lecanicillium conodial state of C. militaris are produced and can be used with simplified injection protocols involving spraying or dipping in conidial suspensions than the more material- and labor- intensive injection protocol. The studies to be repored include quantitative tests of conodial yields on varying carbon sources, varying nitrogen sources, and attempted to optimize the carbon/nitrogen ratio and pH of the medium for conidial production.
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