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An ion optical analysis of a static mass analyzer, based on a second-order focusing magnetic mirror, was conducted while accounting for aberrations caused by the movement of ions outside the mean plane of the mass analyzer. As part of this study, an optimization algorithm was developed for the four-dimensional acceptance of the mass analyzer at a fixed resolution, formulated within the framework of the inverse problem.

The first-order input and output edge transfer matrix elements of the magnetic sector in a static mass spectrometer are derived based on the conservation law of the generalized momentum of ions in a magnetic field. The structure of the edge matrix is shown to be ambiguous and dependent on the effective model, which considers the displacement of ion trajectories in the edge field. A comparison of the results obtained with traditional methods, such as expanding the edge field components and trajectory equations into asymptotic series and integrating successive approximations, reveals significant differences in the first-order edge matrix elements in the effective model of the magnetic sector, where the ideal uniform field is bounded by Herzog boundaries, compared to the published data. Algorithms for matching the input and output axes of the magnetic sector, taking into account the action of the edge fields, are given.

AbstractWe derived identities that relate the angular and coordinate elements of the 2nd order transfer matrix, which determine the axial aberration of static mass analyzers in the fringing field of the magnetic sector with an arbitrary entrance of ions. These identities can be used as criteria for the correct calculation of the axial aberration of the mass analyzer and its resolution.

The research was performed to develop a scientific and methodological approach to the analysis of the dynamics of water erosion based on GIS technologies and Earth remote sensing data, using the fractal dimension index. This approach was tested by the example of a local area (Budennovskii test plot) of ploughed slope lands located in Budennovsk district of Stavropol krai. The research was based on modern geoinformation technologies and Earth remote sensing data for 2007, 2008, 2010, and 2022, which were used to create a retrospective digital relief model of the study area. Freely available images from the ALOS PULSAR and Sentinel-1 satellites, were taken as data sources, which significantly expanded the range of their application. The topography of the area of the Budennovskii test plot is dominated by southern slopes (28%), the mean slope steepness is 2.3°, and watercourses of six orders are typical. The value of the fractal dimension index (geometric complexity of the figure) increases from 0.79 in 2007 to 0.86 in 2022, which indicates the enhancement of water erosion processes. Identification of areas with a rise in this index will allow us to effectively plan measurers for erosion control, paying most attention to areas with significant increases. The proposed scientific and methodological approach may be applied in any agrarian region of Russia taking into account soil-climatic and morphometric features. It enables quick and reliable assessment of the degradation processes over vast areas.

AbstractAn objective criterion of the computation accuracy of ion trajectories aberration components in magnetic edge fields of static mass analyzers is derived.

Since its initial detection in Africa, the West Nile virus has disseminated widely across all continents, becoming endemic in numerous countries, including the Russian Federation. A substantial expansion of the West Nile virus range was observed in the European part of the Russian territory in 1999. In light of this epidemiological trend, research endeavours focusing on monitoring West Nile virus circulation activity in endemic regions of the country have gained paramount significance. A substantial dataset has been accrued from 2007 onwards regarding genomic variability and dissemination dynamics across the country throughout the entire monitoring period for the West Nile fever pathogen. The objective of this study was to characterise West Nile virus isolates that have been circulating in the Russian Federation and identify their molecular and genetic characteristics. A phylogenetic analysis of 55 complete genome sequences revealed that the West Nile virus population within the Russian Federation is genetically heterogeneous and is represented by four major clades. One of these clades is currently exhibiting extensive spread into new regions of the country.

We propose the design of a compact Mattauch–Herzog ion-optical system featuring a double-focusing static mass spectrometer with a cylindrical electrostatic deflector. This system offers second-order angle focusing and first-order energy focusing along the focal line. The collimating system ensures the optimal vertical acceptance of the mass analyzer and maximum ion transmission within the working mass range. The described ion-optical system serves as a foundation for small-sized mass spectrometers, weighing up to ~50 kg, including turbo-molecular and foreline pumps, while maintaining high analytical performance.

Thermoelectric properties of cobalt monosilicide CoSi and (Co 1 – x M x Si, M = Fe, Ni) alloys are studied. Alloy compositions with an iron content of up to 10 at % and nickel content of up to 5 at % are examined. The thermoelectric power and electrical resistivity are measured at temperatures in the range 100–800 K. Recent calculations of the band structure of cobalt monosilicide have revealed a number of significant differences from the standard semi-metallic model with the energy overlap of parabolic bands for electrons and holes. This requires the modification of previously employed models to describe the transport properties. The possibility of theoretical description of the experimental temperature and concentration dependences of the thermoelectric power and electrical resistivity with the use of different models for description of the electronic spectrum is analyzed.

AbstractThe axial aberration of the ion-optical system of a static mass analyzer is one of the main factors limiting the transmission and sensitivity of the instrument. We described an algorithm for selecting the optimal collimating system for a mass analyzer, which makes it possible to decrease this aberration effectively, with minimal loss in the intensity of the mass spectral lines. The algorithm is based on the representation of the considered aberration in the phase space as an ellipse and the optimal approximation of this aberration ellipse by a polygon with a given number of vertices. In the absence of constraints, the solution of the corresponding optimization problems is in phase polygons generated by regular polygons inscribed in a unit circle or circumscribed around a unit circle with the same number of vertices. After that, the unit circle along with the polygons is “stretched” to the size of the specified aberration ellipse along its main axes. Additional freedom of the rotation of the original polygon around the center of the unit circle can be used to position auxiliary slits of the collimating system more conveniently.

AbstractAxial aberration of the ion-optical system of a static mass analyzer is one of the factors limiting the transmittance and sensitivity of the device because of a need in significantly decreasing the vertical component of the ion beam emittance to get the required mass spectral resolution. We described an algorithm for selecting the optimal collimating system of the mass analyzer, which effectively decreases the contribution of axial aberration with minimal loss of the intensity of mass spectral lines.