Advances in the understanding of molybdenum effect on iodine and caesium reactivity in condensed phase in the primary circuit in nuclear severe accident conditions

Gouëllo Mélany,Hokkinen Jouni,Kärkelä Teemu 한국원자력학회 2020 Nuclear Engineering and Technology Vol.52 No.8

In the case of a severe accident in a Light Water Reactor, the issue of late release of fission products, from the primary circuit surfaces is of particular concern due to the direct impact on the source term. CsI is the main iodine compound present in the primary circuit and can be deposited as particles or condensed species. Its chemistry can be affected by the presence of molybdenum, and can lead to the formation of gaseous iodine. The present work studied chemical reactions on the surfaces involving gaseous iodine release. CsI and MoO3 were used to highlight the effects of carrier gas composition and oxygen partial pressure on the reactions. The results revealed a noticeable effect of the presence of molybdenum on the formation of gaseous iodine, mainly identified as molecular iodine. In addition, the oxygen

Comparison of the cyclic fatigue resistance of One Curve, F6 Skytaper, Protaper Next, and Hyflex CM endodontic files

Gouédard Charlotte,Pino Laurent,Arbab-Chirani Reza,Arbab-Chirani Shabnam,Chevalier Valérie 대한치과보존학회 2022 Restorative Dentistry & Endodontics Vol.47 No.2

Objectives This study compared the cyclic fatigue resistance of One Curve (C wire) and F6 Skytaper (conventional austenite nickel-titanium [NiTi]), and 2 instruments with thermo-mechanically treated NiTi: Protaper Next X2 (M wire) and Hyflex CM (CM wire). Materials and Methods Ten new instruments of each group (size: 0.25 mm, 6% taper in the 3 mm tip region) were tested using a rotary bending machine with a 60° curvature angle and a 5 mm curvature radius, at room temperature. The number of cycles until fracture was recorded. The length of the fractured instruments was measured. The fracture surface of each fragment was examined with a scanning electron microscope (SEM). The data were analyzed using one-way analysis of variance and the post hoc Tukey test. The significance level was set at 0.05. Results At 60°, One Curve, F6 Skytaper and Hyflex CM had significantly longer fatigue lives than Protaper Next X2 (p < 0.05). No statistically significant differences were found in the cyclic fatigue lives of One Curve, F6 Skytaper, and Hyflex CM (p > 0.05). SEM images of the fracture surfaces of the different instruments showed typical features of fatigue failure. Conclusions Within the conditions of this study, at 60° and with a 5 mm curvature radius, the cyclic fatigue life of One Curve was not significantly different from those of F6 Skytaper and Hyflex CM. The cyclic fatigue lives of these 3 instruments were statistically significantly longer than that of Protaper Next. Objectives This study compared the cyclic fatigue resistance of One Curve (C wire) and F6 Skytaper (conventional austenite nickel-titanium [NiTi]), and 2 instruments with thermo-mechanically treated NiTi: Protaper Next X2 (M wire) and Hyflex CM (CM wire). Materials and Methods Ten new instruments of each group (size: 0.25 mm, 6% taper in the 3 mm tip region) were tested using a rotary bending machine with a 60° curvature angle and a 5 mm curvature radius, at room temperature. The number of cycles until fracture was recorded. The length of the fractured instruments was measured. The fracture surface of each fragment was examined with a scanning electron microscope (SEM). The data were analyzed using one-way analysis of variance and the post hoc Tukey test. The significance level was set at 0.05. Results At 60°, One Curve, F6 Skytaper and Hyflex CM had significantly longer fatigue lives than Protaper Next X2 (p < 0.05). No statistically significant differences were found in the cyclic fatigue lives of One Curve, F6 Skytaper, and Hyflex CM (p > 0.05). SEM images of the fracture surfaces of the different instruments showed typical features of fatigue failure. Conclusions Within the conditions of this study, at 60° and with a 5 mm curvature radius, the cyclic fatigue life of One Curve was not significantly different from those of F6 Skytaper and Hyflex CM. The cyclic fatigue lives of these 3 instruments were statistically significantly longer than that of Protaper Next.

웹기반 구조중심 협동학습 시스템의 설계 및 구현

정규옥,양형정,최숙영 한국컴퓨터교육학회 2004 컴퓨터교육학회 논문지 Vol.7 No.3

협동학습 모델 중에서 매우 간단하고 적용이 쉬운 구조중심 협동학습은 다양한 구조의 유기적 연결과 학습내용의 결합을 통해 교수학습이 이루어진다. 본 연구에서는 이러한 구조중심의 협동학습을 위한 교수-학습 모델을 제안하고, 이를 지원하는 웹기반 구조중심 협동학습 시스템을 설계 및 구현하였다. 본 연구에서 제안하는 구조중심 협동학습 모델에서는 교과학습에 적용할 수 있는 구체적인 틀을 제시하여 협동학습을 효과적으로 지원할 수 있도록 하였다. 또한 학습 내용과 형태에 따라 다른 구조를 적용할 수 있도록 지식 습득형, 탐구형, 기능 숙달형 구조로 분류하고 이에 따른 적용 모형들을 제시하고 있다. 이러한 모형들을 기반으로 실제 협동학습을 수행할 수 있도록 시스템을 구현하여, 수업에 적용한 후 그 효과를 분석해 보았다. One of the cooperative learning models, the cooperative learning of structural approach which is very simple and easily applicable accomplishes teaching-learning through combining learning contents and organic connections of various structures. This work proposes a cooperative teaching-learning model for the structural approach, designs and implements a web-based cooperative system supporting it. The model provides a concrete frame which can apply to a subject learning thus could effectively support cooperative learning. Furthermore, it classifies learning into three types such as knowledge learning, investigation, and function mastering and presents a structure application model for each so as to apply different structures according to learning materials and types. We implemented a system that performs cooperative learning on the basis of these models, applied to a class, and analyzed the effect of it.

政治社會化와 그 內容

李球載 서울 敎育大學校 1977 論文集 Vol.10 No.-

國家觀 確立을 위한 敎育에서 考慮되어야 할 몇 가지 問題點

球 載 서울 敎育大學校 1976 論文集 Vol.9 No.-

Use of Denaturing High-Performance Liquid Chromatography (DHPLC) to Characterize the Bacterial and Fungal Airway Microbiota of Cystic Fibrosis Patients

Jérôme Mounier,Geneviève Héry-Arnaud,Audrey Gouëllo,Marlène Keravec,Solène Le Gal,Grégory Pacini,Stella Debaets,Gilles Nevez,Gilles Rault,Georges Barbier 한국미생물학회 2014 The journal of microbiology Vol.52 No.4

The aim of this study was to evaluate the use of denaturinghigh-performance liquid chromatography (DHPLC) to characterizecystic fibrosis (CF) airway microbiota includingboth bacteria and fungi. DHPLC conditions were first optimizedusing a mixture of V6, V7 and V8 region 16S rRNAgene PCR amplicons from 18 bacterial species commonlyfound in CF patients. Then, the microbial diversity of 4 sputumsamples from 4 CF patients was analyzed using culturalmethods, cloning/sequencing (for bacteria only) and DHPLCpeak fraction collection/sequencing. DHPLC analysis allowedidentifying more bacterial and fungal species than the classicalculture methods, including well-recognized pathogenssuch as Pseudomonas aeruginosa. Even if a lower number ofbacterial Operational Taxonomic Units (OTUs) was identifiedby DHPLC, it allowed to find OTUs unidentified bycloning/sequencing. The combination of both techniquespermitted to correlate the majority of DHPLC peaks to definedOTUs. Finally, although Aspergillus fumigatus detectionusing DHPLC can still be improved, this techniqueclearly allowed to identify a higher number of fungal speciesversus classical culture-based methods. To conclude, DHPLCprovided meaningful additional data concerning pathogenicbacteria and fungi as well as fastidious microorganisms presentwithin the CF respiratory tract. DHPLC can be consideredas a complementary technique to culture-dependentanalyses in routine microbiological laboratories.

Symposia : Vascular Biology and Diseases ; Ovarian cancer induces profound Iymphangiogenesis

( Gou Yong Koh ) 한국생화학분자생물학회 (구 한국생화학회) 2007 생화학분자생물학회 춘계학술발표논문집 Vol.2007 No.-

Dryland agricultural environment and sustainable productivity

Gou-Xia Li,Bing-Cheng Xu,Li-Na Yin,Shi-Wen Wang,Sui-Qi Zhang,Lun Shan,곽상수,Qingbo Ke,Xi-Ping Deng 한국식물생명공학회 2020 Plant biotechnology reports Vol.14 No.2

Global climate change is expected to cause progressively increased frequency and severity of drought events, which further seriously limit plant growth and crop yields. Increasing water use effi ciency (WUE) and yield per unit rainfall are one of the most important challenges in dry land agriculture. Here, we reviewed the comprehensive technical strategies including conserving water to combine both increased agricultural productivity and resource conservation; enquiring into how crop plants respond to drought through morphological, physiological, and molecular modifi cations that occur in all plant organs; breeding for drought tolerance where there is a delineated stress environment and genotype × environment interactions are stable; eff ective conservation of rainfall and high effi ciency of use. In addition, we discussed the preponderance of biological water-saving measures, which embraces improvements in WUE and drought tolerance, by genetic improvement and physiological regulation. Sustainable agriculture would be benefi ted from modern engineering such as biological engineering, conservation tillage, and breeding technologies.

Ni-Al 합금계에서 평형 및 비평형 공정조직 특성 (초)

( Gou Bin ),노운,이재현,오명훈,위당문 대한금속재료학회 ( 구 대한금속학회 ) 2007 대한금속재료학회 학술대회 개요집 Vol.2007 No.1

Inactivation Kinetics and Virulence Potential of Salmonella Typhimurium and Listeria monocytogenes Treated by Combined High Pressure and Nisin

GOU, JINGYU,LEE, HYEON-YONG,AHN, JUHEE International Association for Food Protection 2010 Journal of food protection Vol.73 No.12

<P>The aim of this study was to characterize the physiological and molecular changes of Salmonella Typhimurium and Listeria monocytogenes in deionized water (DIW) and nisin solutions (100 IU/g) during high pressure processing (HPP). Strains of Salmonella Typhimurium and L. monocytogenes in DIW or nisin solutions were subjected to 200, 300, and 400 MPa for 20 min. The Weibull model adequately described the HPP inactivation of Salmonella Typhimurium and L. monocytogenes. Salmonella Typhimurium and L. monocytogenes populations were reduced to less than 1 CFU/ml in DIW and nisin solutions under 400 MPa. The highest b value was 5.75 for Salmonella Typhimurium in nisin solution under 400 MPa. L. monocytogenes was more sensitive to pressure change when suspended in DIW than when suspended in nisin. The pressure sensitivity of both Salmonella Typhimurium and L. monocytogenes was higher in DIW solution (141 to 243 MPa) than in nisin solution (608 to 872 MPa). No recovery of HPP-injured cells in DIW and nisin solutions treated at 400 MPa was observed after 7 days of refrigerated storage. The heterogeneity of HPP-treated cells was revealed in flow cytometry dot plots. The transcripts of stn, invA, prfA, and inlA were relatively down-regulated in HPP-treated nisin solution. The combination of high pressure and nisin could noticeably suppress the expression of virulence-associated genes. These results provide useful information for understanding the physiological and molecular characteristics of foodborne pathogens under high-pressure stress.</P>