Results of ground‐based measurements of the atmospheric electricity parameters at the network of middle‐ and high‐latitude observatories are used for the investigation of the space‐time structure of regular and irregular variations of the atmospheric electricity of fair weather Regular diurnal variations contain a complex superposition of universal, local, and magnetic local time controlled variations. Amplitudes of these components depend on season, latitude, and height of an observatory above the sea level. Subdivision of the irregular atmospheric electricity variations, in accordance with their space and time structure and physical nature, helps to extract the particularities of atmospheric electricity responses to the different geophysical events, such as the complex of global phenomena joined by the term “geoeffective solar flare” and inclusive solar proton events, Forbush decreases of galactic cosmic ray fluxes and planetary magnetic storms; and regional phenomena in atmospheric electricity conditioned by magnetospheric substorms in high latitudes and by the Chernobyl (Ukraine) nuclear accident (1986) in Eastern Europe.

The dynamics of the anthropogenic atmospheric pollution level is evaluated using atmospheric electrical data obtained at a network of stations. These stations are distributed at midlatitude plain and mountain stations and also at two high‐latitude stations on the Kola Peninsula. The anthropogenic atmospheric pollution level is estimated from a comparison of atmospheric electricity data measured on weekdays with data measured on Sundays, when work‐related pollution activities are reduced.

No abstract

The article is devoted to the development of an EUV microscope using a wavelength of 13.84 nm. Due to the use of a mirror lens with a large numerical aperture, NA = 0.27, and a short depth of focus, it has been possible to carry out z-tomography of bio-samples for the first time with this type of microscope. A 3D image was reconstructed, and a pixel resolution of 140 nm was obtained. A new simple algorithm for the 3D reconstruction of absorption images from z-tomography data has been proposed that takes into account lens aberrations and a point spread function. The algorithm reduces the inverse absorption task to the corresponding well-studied task of fluorescence microscopy, with an error of 10% for cells up to 10 µm thick.

The behavior of sputtering yield and the surface roughness of monocrystalline silicon of orientations ⟨ 100 ⟩ , ⟨ 110 ⟩ , and ⟨ 111 ⟩ under the ion-beam bombardment by neutralized Ar ions with energies of 200–1000 eV is studied. The significant dependence (modulation) of sputtering yield on incidence angle due to crystalline structure is observed. It is shown that a sharp increase in the sputtering yield and a decrease in the effective surface roughness at energies above 400 eV occurs. At energies of more than 400 eV for orientations ⟨ 100 ⟩ , ⟨ 110 ⟩ , and ⟨ 111 ⟩ at normal ion incidence, smoothing of the effective roughness in the range of spatial frequencies ν ∈ [ 4 . 9 ⋅ 1 0 − 2 − 6 . 3 ⋅ 1 0 1 µ m − 1 ] up to a value of 0.17 nm is observed. This makes it possible to use the ion-beam etching technique for finishing polishing, aspherization, and correction of local shape errors of single-crystal silicon substrates, which are of the greatest interest for synchrotrons of the 3rd+ and 4th generation and x-ray free electron lasers.