Dose-response functions (DRFs) developed for the prediction of first-year corrosion losses of carbon steel and zinc (K1) in continental regions are presented. The dependences of mass losses on SO2 concentration, K = f([SO2]), obtained from experimental data, as well as nonlinear dependences of mass losses on meteorological parameters, were taken into account in the development of the DRFs. The development of the DRFs was based on the experimental data from one year of testing under a number of international programs: ISO CORRAG, MICAT, two UN/ECE programs, the Russian program in the Far-Eastern region, and data published in papers. The paper describes predictions of K1 values of these metals using four different models for continental test sites under UN/ECE, RF programs and within the MICAT project. The predictions of K1 are compared with experimental K1 values, and the models presented here are analyzed in terms of the coefficients used in the models.
Attitude motion of satellites orbiting an asteroid is examined. The highly irregular shape of the asteroids along with their rotational states can lead to very interesting attitude dynamics. As a start, the case of uniform rotation of the asteroid is examined and attention is focused on planar attitude motion (pitch). Four asteroids, Vesta, Eros, Gaspra, and Castalia, are considered. For the case of circular equatorial orbits, the radius for which resonant pitch oscillations are excited, is determined. It is noticed that for slowly rotating large asteroids such as Vesta, more than one resonant region can exist. Stability of pitch motion is significantly affected by the rotational state as well as the shape of the small body. General threedimensional attitude motion is considered next. Orbits corresponding to large 3D motion are identified.
This paper presents various models (dose-response functions, DRFs) for predicting the first-year corrosion losses of structural metals for areas with marine and marine-urban (industrial) atmospheres. The prediction results for the first-year corrosion losses (C 1 pr ) calculated by the DRF from the ISO 9223 standard and by the DRF developed by us are presented. A comparative assessment of the results is given. In this work, we used experimental data on the corrosion losses of carbon steel (CS), Zn, Cu, and Al over the first year of exposure (C 1 ex ) at coastal test locations conducted within the MICAT project and the Russian programmes. The atmosphere corrosivity parameters necessary for the DRFs were considered for these locations. It was shown that the development of DRFs that provide the most reliable C 1 pr requires experimental data from one-year metal exposures with orientation of the samples in the direction facing the predominant sea wind directions.
The corrosivity of atmosphere in the continental territory of Russia toward carbon steel, zinc, copper and aluminium was determined and estimated. The atmosphere corrosivity was determined from experimental data on first-year corrosion losses in representative test locations. The atmosphere corrosivity was estimated using first-year corrosion losses of structural materials calculated by means of dose-response functions: new ones (DRF N ) and those presented in ISO 9223 (DRF S ). Estimation of atmosphere corrosivity in the Russian Federation (RF) territory was performed using the data bank of the Institute of physical chemistry and electrochemistry of the Russian Academy of Sciences containing long-term annual average meteorological atmosphere parameters. The mapping of RF continental territory by categories of atmosphere corrosivity is presented. The atmosphere corrosivities estimated by DRF N and DRF S for each metal are compared. It has been shown that DRF N provides more reliable atmosphere corrosivity estimates.
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