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isobars Separation (137Cs-137mBa-137Ba) from Marine Sediments, in Order to Evaluate Directly Their Radioactive Contamination by Mass Spectrometry

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World Journal of Nuclear Science and Technology 2020年第1期10卷 32-38页

作者： Karla Fernández Juan Manuel Navarrete Miguel Angel Zúñ iga Ernesto Hernández Department of Inorganic and Nuclear Chemistry Faculty of ChemistryNational Autonomous University of MexicoMexico CityMexico

Marine sediments contamination by fission product 137Cs-137mBa is a fact since the period 1945-65, when plus than two thousand atomic explosion tests were performed mainly in the southern seas, earth region with minor population density. However, marine flows have produced dissemination of this radioactive pair through the sea bottom all over the world, at different levels, because the sea movement and natural decaying of radioactive pair: parent 137Cs (t1/2 = 30.17 years) and daughter 137mBa (t1/2 = 2.55 minutes). Radioactive detection of these contaminants, compared as percentage with that of natural 40K (t1/2 = 1.28 × 109 years, 0.0118% of elementary K) leads to radiation contamination factor (RCF), as one possible unit to measure the radioactive contamination intensity in different regions, as well to determine if there is some other possible source of this contaminant, for example water cooling from power nuclear reactors when it is discharged at sea. However, radioactive detection always implies an unavoidable statistical variation, which makes more difficult to appreciate the changes as function of time and region. But at beginning of this century, mass spectrometry has got impressive advances, which makes it much more precise and sensible than radioactive detection [1]. This paper attempts to measure with other units the radioactive contamination: 137Cs atoms number per gram of sample, instead radioactivity, which could be more direct and with minor standard deviation that radioactive detection, solving at same time the isobars separation: 137Cs versus 137mBa plus elementary 137Ba (11.23% of Ba element).

关键词： isobars Separation 137Cs-137mBa-137Ba

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大量镱同质异位素干扰下镥同位素丰度比的测量

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质谱学报 2005年第Z1期26卷 43-44页

作者：徐江朱凤蓉李志明翟利华邓虎李冬梅西北核技术研究所西安710024 西北核技术研究所西安710024 西北核技术研究所西安710024 西北核技术研究所西安710024 西北核技术研究所西安710024 西北核技术研究所西安710024

The method of lutetium isotopic ratio determined by thermal ionization mass spectrometry (TIMS) with a mass of interference isobars Yb was developed. In this method, isotopic ratio of Lu R176/175 was analysed by linea... 详细信息

关键词： elements of isobars Yb Lu TIMS isotopic ratio

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Design and Application of a New Splitter Plate Pressure Probe for Wind Tunnel Flow Measurements

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Journal of Mechanics Engineering and Automation 2019年第6期9卷 188-192页

作者： Kasim Biber Department of Mechanical Engineering Faculty of EngineeringArchitecture and DesignBartin UniversityBartin 74100Turkey

A new siplitter plate presure probe was developed for flow field measurements on an airfoil with slotted flap in a low speed wind tunnel with 7 by 10 ft test section. Wind tunnel tests were conducted at a Reynolds number of 2.2 million and Mach number of 0.13. The splitter plate was made of aluminum and had pressure taps on its one side. The probe can make many measurements in the plane of the plate simultaneously by using these pressure tabs. It was supported by a traversing strut in the wind tunnel and surveyed the flow field on the airfoil upper surface. Measured pressures were presented by isobars of coefficients. These isobars were connected with the pressure coefficients distributed over the airfoil. Results of splitter plate pressure probe compare well with other single-point measuring probes. However, results show that no matter how small the probe, its presence in the flow causes a disturbance, especially in the highly time-dependent separated flow regions.

关键词： Splitter plate-pressure probe flow field pressures wind tunnel instrumentation flow field isobars multi-element

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