ITER (International Thermonuclear Experimental Reactor) is a nuclear fusion research and engineering project. It is supposed to be the first fusion device to test the integrated technologies, ...materials and operational regimes necessary for the commercial production of fusion-based electricity. Front (explored in this paper) and Back diagnostic racks are used as supporting structures of the so-called ITER Divertor Thomson Scattering (DTS) Diagnostic System that is created to measure plasma characteristics. They will be attached to the lower port walls (ITER ports are used to locate diagnostic equipment and its supporting structures) through the so-called Divertor Rails. The developed design of the Front (Diagnostic) Rack locking (e.g. Rack attachment to the rails mechanism) was analyzed in this research to be consistent with thermal stresses, electromagnetic and seismic loads taking into account some specific assembly and maintenance loads including preloading under installation. The analysis of the rack locking design's resistance to the mentioned loads should prove correspondence of the suggested common rack design with the structure integrity criterions. Construction strength under the most severe loading scenario was estimated in this research and appropriate conclusions were made. It was found out that the stress criterion was not fully satisfied, so a new rack locking design concept was proposed. Its main details are also described at the end of this article.
A neutron collimator is developed to attenuate the neutron flux and reduce the residual induced activity in the interportal space of the diagnostic system of neutral particle analyzers of the ITER ...tokamak reactor. The collimator is installed in the port plug of the ITER vacuum vessel in front of an inlet to the vacuum pipeline of the diagnostic system. The collimator design has a cellular structure with 80% transparency for the neutral atom beam that goes out of the plasma and is recorded by the analyzers. However, because of increased scattering of neutrons in the collimator, their flux in the interportal room in the service zone of diagnostic systems of equatorial port no. 11 is significantly reduced and allows the equivalent dose rate in this zone to be decreased by several times. Thermal analysis showed that, during the reactor operation in modes with generation of the maximum power of 500 MW, the plasma radiation will cause the heating of the collimating grid to a temperature not exceeding 250°C, which makes it possible to select the stainless steel (316L(N)-ITER grade) as a material for manufacturing the collimator. In this case the cyclic strength of the collimator meets the ITER requirements, and it can be used without replacement during the entire deuterium-tritium experiment of the tokamak reactor.
The microstructure, hardness and cavitation wear of T91 ferritic-martensitic steel are studied and compared with some other reactor steels of the Eurofer 97 and Cr18Ni10Ti grades. It is shown that ...the cavitation resistance of T91 steel is 34 times higher than the cavitation resistance of Eurofer 97 steel and 11 times higher than the resistance of traditionally used Cr18Ni10Ti austenitic steel. Unlike the Eurofer 97 ferritic-martensitic steel alloyed with tungsten and tantalum, the T91 steel alloyed with molybdenum and niobium has larger prior austenite grain sizes (20 vs. 6 μm), length and width of martensitic packets (30–40 and 3–10 vs. 10–20 and 2–4 μm, respectively), and microhardness (2.47 vs. 2.07 GPa).
•ITER Divertor Thomson scattering system collecting mirrors are heated up to 95 °C.•Mirror surface deformation and rotation values were obtained.•Optical system should be explored under seismic and ...electromagnetic loads as well.
ITER is a nuclear fusion research and engineering project. It is supposed to be the first fusion device designed for testing the integrated technologies, materials, and physical aspects necessary for development of the commercially available fusion-power plant. One of the important components of the project is optical diagnostic systems with collecting mirrors. These mirrors have to provide stability of optical systems under severe loads of different types that could possibly arise in the tokamak. The collecting mirrors of several ITER diagnostics have a large scale and should be installed into diagnostic ports. Thermal stress analysis of the mirror updated design is aimed to obtain deformation and rotation values of the mirrors’ reflecting surfaces in order to conduct ray tracing analysis and to edit mirrors alignment to provide correct functioning of the optical systems. The maximum temperature values of the Divertor Thomson Scattering collecting mirrors were estimated for the normal operation mode. The FE model of the second mirror takes into account all the force boundary conditions, basic kinematic boundary conditions and constraints. Boundary conditions taken for the simulation were applied on surfaces contacting with the diagnostic rack. Thermally stressed state was calculated and corresponding displacement and rotation distributions were obtained.
PdO sub(x)/SiO sub(2) + TiO sub(2)/Ti composites with different palladium contents have been fabricated by a combination of plasma electrolytic oxidation and template sol-gel synthesis on titanium ...substrates. The effect of multiplicity of deposition of titanium hydroxide gel with palladium nanoparticles on the composite composition and the surface morphology has been investigated. It has been established that the coatings surface is heterogeneous: it is built from alternating sites of different types with varying palladium content. Palladium is concentrated in nanosized structures of a diameter of 25-60 nm. The fabricated composites catalyze the reaction of oxidation of CO into CO sub(2) at temperatures above 170degreesC. It has been demonstrated that at the average concentration of palladium in coatings equal to 0.04 at.% the activation energy for this reaction is equal to ~55 kj/mol, whereas at 0.1-0.2 at.% it is equal to ~46 kJ/mol.
Personalized medicine - a new direction in medicine, which is based on the study of various biomarkers and the use of new methods of molecular analysis (primarily evaluating the activity of ...isoenzymes of cytochrome P450), allowing individualized approach to the selection of both the drugs and the selection of the dosing regimen for the purpose of maximize the effectiveness and safety of pharmacotherapy. This personalized medicine is to change the development and use of preventive and curative interventions. Genetic polymorphism isozymes of cytochrome P450 may determine the individual activity of a particular isozyme, and thus, to predict the clinical effectiveness, and in some cases, the risk of adverse reactions. The article is an example of the use of information on the activity of cytochrome P450 in clinical practice in matters of diagnosis, treatment and prevention of diseases. The scheme of the five best-known activity of isoenzymes of cytochrome P450 is shown.
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