Haut PDF Nuclear corrosion and materials: achievements and challenges

Nuclear corrosion and materials: achievements and challenges

Nuclear corrosion and materials: achievements and challenges

Damien Féron | November 2016 | PAGE 17 This document is CEA’s property. It cannot be disclosed without prior authorization. Oxidation rates of Zircaloy-4 ® and M5 ® measured in primary water conditions by autoclave tests (at 360°C, with 10 ppm of Li and 650 ppm of B in water). Cycles appear with transitions

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Corrosion issues in pressurized water reactors : achievements and challenges

Corrosion issues in pressurized water reactors : achievements and challenges

NUPP 2017 I Damien Féron | February 2017 | PAGE 26 This document is CEA’s property. It cannot be disclosed without prior authorization. MAJOR COUNTERMEASURES TO FAC IN POWER PLANTS  Importance of the design of the components, modeling and prediction of degradations (COMSY, BRT-CICERO, WATHEC, CHECWORKS…) coupled with non-destructive examinations.

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Nuclear corrosion: achievements et challenges

Nuclear corrosion: achievements et challenges

Damien Féron | February 17, 2016 | PAGE 25 Results included in this document are CEA’s property. They cannot be disclosed without prior authorization . Corrosion in “oxidising” liquid metals: oxidation & dissolution (Na, with high oxygen content)

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Challenges, mitigation strategies and perspectives in development of zinc-electrode materials and fabrication for rechargeable zinc–air batteries

Challenges, mitigation strategies and perspectives in development of zinc-electrode materials and fabrication for rechargeable zinc–air batteries

3. Conclusion and perspectives As a promising energy storage device, the RZAB has attracted increasing attention due to its high energy density, safety, rich abundance and environmental compatibility. However, several challenges are required to be addressed before its practical application, which are mainly from the zinc-electrode, electrolyte and air-electrode. In this review, we overview the challenges and promising multiple solutions of zinc-electrodes for RZABs. From the above discussion, it can be seen that the challenges associated with zinc-electrodes are mainly induced by dendrite, corrosion, shape change and passivation. The appealing strategies for performance-improved zinc- electrodes are primarily concentrated on the aspects of the electrolyte and electrode, as seen in Fig. 23. Thus, it is required to design and prepare novel zinc electrodes. Generally, com- pared to a planar electrode or a powder electrode, porous zinc- electrodes, typically composed of the conductive material, the current collector, the gelling agent/binder, and the additives, would be desired because they can deliver higher capacity owing to their high accessible area by the electrolyte. The effects of the above four components on the electrochemical properties of the zinc-electrode are nonnegligible. The elec- trode components should be optimized through innovative design and preparation by combining the effects of electrode structure additives, inorganic corrosion inhibitors and poly- mer additives on the suppression of the formation of zinc dendrites and the alleviation of Zn corrosion. Therefore, one of the key tasks to achieve long cycle life of zinc-electrodes is to develop a zinc-based composite electrode with proper compo- nents and additives through optimized preparation processes. With this in mind, more effective and low-cost inorganic or organic materials should be developed to solve the technical issues in the future. Besides the zinc-electrode, it is worthwhile
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Overview on nuclear corrosion - Corrosion in the nuclear cycle

Overview on nuclear corrosion - Corrosion in the nuclear cycle

III. Sheir’s corrosion, Volume 2, 4th edition, by R.A Cottis, M.J. Graham, R. Lindsay… 2010, published by Elsevier, U.K. IV. Corrosion and alteration of nuclear materials, C. Richet & D. Féron, Nuclear energy division monography, 2010, Editions le Moniteur, Paris

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Corrosion of structural materials by liquid metals used fusion, fission and spallation

Corrosion of structural materials by liquid metals used fusion, fission and spallation

Liquid metals (lithium, sodium, lead and its alloys Pb-Li or Pb-Bi) are used as coolants for fusion, fission or spallation reactors due to their thermal and nuclear properties. However, these liquid metals are corrosive when they come into contact with solid metallic materials. Preserv- ing structural alloys (no- and low alloyed steels, stainless steels, nickel based alloys…) in con- tact with these liquid metals requires the knowledge of the corrosion phenomena that may oc- cur: mainly liquid metal embrittlement and general corrosion with mass transfers within the heat transfer circuit.
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Corrosion and Green Chemistry

Corrosion and Green Chemistry

Atoms economy: economy of “raw materials” Illustration – extension of exploitation time of industrial equipements Initial nuclear power plants were planned for 30 years, new ones are planned for 60 years of operation and the exploitation of some old ones have been extended to 60 years or more, one reason being a very good corrosion resistance of the alloys.

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Corrosion in nuclear waste geological storages how to predict corrosion for millenniums ?

Corrosion in nuclear waste geological storages how to predict corrosion for millenniums ?

The corrosion resistance of the container material over centuries (long term interim storages) and millenniums (geological waste disposal) is one of the greatest scientific and technical challenges The reliability and the viability of integrity predictions in HLNW storages and disposals are of paramount importance for public acceptance

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Delivery of Proteins and Nucleic Acids: Achievements and Challenges

Delivery of Proteins and Nucleic Acids: Achievements and Challenges

The inability of macromolecules to gain access to the cytosol and nucleus has consequences. For example, about 80% of extant drugs are small molecules, half of which act on extracellular targets (e.g., GPCRs) and half of which act on intracellular targets (e.g., protein kinases and nuclear hormone receptors). In marked contrast, virtually all macromolecular drugs act on extracellular targets (e.g., tumor antigens). Clearly, their barrier to entry is leaving much on the table.

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Fundamentals on corrosion and stress corrosion cracking

Fundamentals on corrosion and stress corrosion cracking

 U. Ehrnsten, « Corrosion and stress corrosion cracking of austenitic stainless steels », chapter 5.05 in « Comprehensive Nuclear Materials, ed. R.J.M. Konings, Elsevier, 2012  P.L. Andresen & G.S. Was, « Irrdiation assited stress corrosion cracking », chapter

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Significant achievements in 2017 : Antigua and Barbuda

Significant achievements in 2017 : Antigua and Barbuda

b. Support the Food and Nutrition Department of the Ministry of Education, The Rural Women’s Group and other government agencies (Prison, Fiennes Institute) in building capacity in bread baking utilizing sweet potato and cassava. The training focused on utilizing local roots and tubers to make bread and other baking by- products. Twenty women benefited from this training. Under the APP the utilization of local commodities to develop new enterprise and market opportunities was also a focus.

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Significant achievements in 2017 : Trinidad and Tobago

Significant achievements in 2017 : Trinidad and Tobago

A forage demonstration and multiplication plot for increasing the productivity of the dairy goat sector by demonstrating the use of locally grown forages to replace imported concentrate feed was established in collaboration with the Trinidad and Tobago Goat and Sheep Society. Also, a handbook detailing a quality control system for producing good quality goat’s milk for dairy goat farmers in Trinidad and Tobago was developed in collaboration with the Trinidad and Tobago Goat and Sheep Society (TTGSS). These results were implemented under IICA´s chains project.
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Significant achievements 2018 : Saint Kitts and Nevis

Significant achievements 2018 : Saint Kitts and Nevis

• IICA intensified its efforts to assist the Department of Agriculture to increase the utilization of mangoes. Previ- ously, the pulp extraction process was manual, which was time-consuming and very unproductive. However, IICA introduced a mechanical pulper, which is more efficient, productive and laborsaving - producing 75 pounds of pulp in five minutes. In addition, six members from two coop- eratives and two staff members from the agro-processing facility have now been fully trained in operating the pulper. IICA was instrumental in ensuring that the product is now properly packaged, labelled, and is now sold locally, primar- ily. Trial shipments were made to Anguilla and St. Maarten. • The Institute, in collaboration with the Small Enterprise De-
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Saint Kitts and Nevis: Significant achievements 2020

Saint Kitts and Nevis: Significant achievements 2020

Significant Achievements 2020 • The Inter-American Institute for Cooperation on Agriculture (IICA) provided guidance and technical assistance to the Ministry of Agriculture and Fisheries for the first detection, diagnosis, and survey of Black Sigatoka disease on bananas and plantains in St Kitts and Nevis. IICA has built country capacity by training 88 persons—including plant quarantine officers, agricultu- ral extension officers and farmers—in disease detection; survey strategy; epidemiology and management; and ba- nana crop production.
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Corrosion and decommissioning

Corrosion and decommissioning

Corrosion under Evaporating Salty Sessile Droplets Evaporating corrosion droplet Low salt concentration: c 0 = 10 -3 M NaCl Evaporation of pinned salty sessile droplets causes peripheral salt enrichment Local chloride enrichment promotes the initiation of corrosion

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Fifty years of nuclear corrosion: from a pioneer period to a mature industry and science

Fifty years of nuclear corrosion: from a pioneer period to a mature industry and science

From R. Staehle, Jubilee day, January 26, 2010, CEA-Saclay “COPSON diagram” by CORIOU SCC susceptibility as function of the nickel content (Coriou’s work – summary 1967) Work done with a series of laboratory alloys Fe-18%Cr-Ni with various Ni content Pure water and solution with 0.1% NaCl / 350°C / 6 months / 1.2 and 1.7 E 0.2

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Potential substitutes for critical materials in white LEDs: Technological challenges and market opportunities

Potential substitutes for critical materials in white LEDs: Technological challenges and market opportunities

The methodologies used to define and identify CMs have extensively been reviewed in Refs [6,25– 31]. Overall, the criticality of a material is systematically assessed by quantifying its economic importance (EI), and the corresponding risk of supply shortage (SR). The former is mainly derived from the strategic character of the main applications involving the given chemical element. The latter is determined by the global resources, the reserves, and the distribution of the ores in countries as well as their political stability, the import reliance, but also the recycling rates. Another issue is for instance related to the fact that CMs are by-products whose their production is largely dependent upon the demands of primary products. The extraction of CMs is further affected by environmental regulations and social acceptance, while maintaining a significant level of profitability. When both the EI and SR values of a given material are larger than a subjective threshold value, this material is considered as critical. The presence of substitute materials, described later for the case of wLED, is taken into account for both EI and SR categories. Finally, the environmental implication of a material extraction has only recently been added in certain assessment methodologies, such as the third criterion of criticality, aggregating greenhouse gas emissions and pollution in the broadest sense [28,29,31].
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Probing Interconnectivity in Hierarchical Microporous/Mesoporous Materials using Adsorption and Nuclear Magnetic Resonance Diffusion

Probing Interconnectivity in Hierarchical Microporous/Mesoporous Materials using Adsorption and Nuclear Magnetic Resonance Diffusion

mixture of FAU zeolite and Al-MCM-41 with the same ratio of microporous and mesoporous volumes as in mFAU, but with no hierarchy since no connections between the micro- and mesopores are present, is also considered. Thanks to the use of model materials with well- defined porosities, we show that adsorption can be described using a superimposition principle; i.e. the adsorbed amount at a given pressure can be obtained by a linear combination of the adsorption isotherms for the parent solids (zeolite and Al-MCM-41) where the weighing parameters are the volume fractions occupied by each phase. This result shows that adsorption does not allow distinguishing a true hierarchical material from a material made of independent micro and mesoporosities. In contrast, PFG NMR is shown to allow probing interconnectivity unambiguously in such hierarchical micro/mesoporous zeolites.
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Lock-in thermography for characterization of nuclear materials

Lock-in thermography for characterization of nuclear materials

1 Introduction Lock-in thermography is a non-destructive method which may be applied to test and to ensure remote control over materials in severe environment (e.g. nuclear installations) in a wide temperature range. The method is based on the laser heating of a sample with a modulated laser power at a given frequency f(Hz) followed by measurements of a thermal radiation emitted by the sample. The phase shifts D’ between the laser power and the thermal radiation measured at different modulated frequencies are then compared with those obtained with an analytical (3D + t) model developed at the LISL (DEN/DANS/DPC/SEARS) in case of the heating of a sample covered by a deposited layer [ 1 , 2 ]. Thus, it is possible to provide a tool to characterize some sample properties (thickness, thermal diffusivity, deposited layer/surface thermal contact resis- tance, characterization of under-surface defects and their evolution with time). The phase shift of heating tempera- ture is presented in Figure 1 .
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Detection of Special Nuclear Materials with tagged neutrons

Detection of Special Nuclear Materials with tagged neutrons

detect Special Nuclear Materials in cargo containers. A DT neutron generator, based on the 3 H( 2 H,n) α fusion reaction, produces 14 MeV neutrons which are tagged both in direction and time with an embedded alpha detector. Prompt neutrons and gamma rays emitted during neutron-induced fissions are detected by plastic scintillators, in coincidence with the alpha particle. Nuclear materials are differentiated from non-nuclear materials and cross- talk events using high multiplicity coincidences. The data acquisition electronics is made of compact FPGA boards. Experiments performed with a mock-up of the measurement system are reported and compared to calculations to validate numerical simulation and post-processing tools. Measurements have been performed with different targets made of iron, lead, or uranium, placed in metallic or wood cargo matrixes. The performances of a full scale cargo container inspection system, with a larger number of detectors optimized for container inspection, are also studied by numerical simulation. Random background due to neutrons which are not correlated with an alpha particle, counting statistics, time and energy resolutions of the data acquisition system, are all taken into account to model the measurements as realistically as possible. A wide range of inspections, with the suspicious item in different positions in different cargo matrixes, have been studied.
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