Measurement of strains in zircon inclusions by Raman spectroscopy

We have carried out ab initio hybrid Hartree-Fock/Density Functional Theory simulations to determine the structure and vibrational modes of zircon, ZrSiO4, as a function of different applied strains. The changes in phonon-mode wavenumbers are approximately linear in the unit-cell strains, and have been fitted to determine the components of the phonon-mode Grüneisen tensors of zircon which reproduce the change in measured Raman shifts with pressure. They can therefore be used to convert Raman shifts measured from zircon inclusions in metamorphic rocks into strains that in turn can be used to determine the metamorphic conditions at the time that the inclusion was trapped. Due to the strong anisotropy in the thermal pressure of zircon, the phonon-mode Grüneisen tensor is not able to reproduce the temperature-induced changes in Raman shifts. Because zircon inclusions are normally measured at room conditions this does not prevent the calculation of their entrapment conditions

Lease or easement for a forest plot for linear objects: An economic aspect

In this article, we will consider the interesting, in our opinion, presented data of practitioners and scientists in terms of the study of more cost-effective disposal of forest plots provided for linear objects on the lands of the forest fund of Russia. In our opinion, today it is quite relevant to resolve issues around the payment for the use of forest plots for linear objects for our country: granting the right to lease or establish an easement for the considered plots, as well as conducting forecast financial calculations of these options for the provision of land for 2020. In this article, we only showed forward-looking calculations on the example of the Ural Federal District, which has almost 10% of the country's forest land (almost 60% of the district's area), for conclusions about the damage to the budget due to lost revenue due to the choice of the form of granting forest plots, a more complete study of the economic mechanism of land management of the country is necessary, such a task the authors have not yet set themselves. © The Authors, published by EDP Sciences, 2021

Urban Soils: The Results Of The Study Of The Territory Of The City Of Ekaterinburg

In this article, we will consider the interesting, in our opinion, presented data of practitioners and scientists in terms of studying the formation and composition of urban soils, which is the most objective and stable indicator of man-made pollution, it clearly reflects the spread of pollutants and their actual distribution in the components of the urban environment. In this article, we have only shown the results of the analysis of the soils of g.For the period of the last 10 years, it is possible that for conclusions about the impact of the existing situation of the city territory on the entire environment, a more complete study of not only the chemical composition of soils, but also the impact of the economic mechanism of land management on the state of the city is necessary, the authors have not yet set themselves such a task. © Published under licence by IOP Publishing Ltd

Raman elastic geobarometry for anisotropic mineral inclusions

Elastic geobarometry for host-inclusion systems can provide new constraints to assess the pressure and temperature conditions attained during metamorphism. Current experimental approaches and theory are developed only for crystals immersed in a hydrostatic stress field, whereas inclusions experience deviatoric stress. We have developed a method to determine the strains in quartz inclusions from Raman spectroscopy using the concept of the phonon-mode Grüneisen tensor. We used ab initio Hartree-Fock/Density Functional Theory to calculate the wavenumbers of the Raman-active modes as a function of different strain conditions. Least-squares fits of the phonon-wavenumber shifts against strains have been used to obtain the components of the mode Grüneisen tensor of quartz (γm1 and γm3) that can be used to calculate the strains in inclusions directly from the measured Raman shifts. The concept is demonstrated with the example of a natural quartz inclusion in eclogitic garnet from Mir kimberlite and has been validated against direct X-ray diffraction measurement of the strains in the same inclusion

Raman elastic geobarometry for anisotropic mineral inclusions

Elastic geobarometry for host-inclusion systems can provide new constraints to assess the pressure and temperature conditions attained during metamorphism. Current experimental approaches and theory are developed only for crystals immersed in a hydrostatic stress field, whereas inclusions experience deviatoric stress. We have developed a method to determine the strains in quartz inclusions from Raman spectroscopy using the concept of the phonon-mode Gr\ufcneisen tensor. We used ab initio Hartree-Fock/Density Functional Theory to calculate the wavenumbers of the Raman-active modes as a function of different strain conditions. Least-squares fits of the phonon-wavenumber shifts against strains have been used to obtain the components of the mode Gr\ufcneisen tensor of quartz (\u2060\u3b3m1 and \u3b3m3\u2060) that can be used to calculate the strains in inclusions directly from the measured Raman shifts. The concept is demonstrated with the example of a natural quartz inclusion in eclogitic garnet from Mir kimberlite and has been validated against direct X-ray diffraction measurement of the strains in the same inclusio

Silver zeolite-loaded silicone elastomers: a multidisciplinary approach to synthesis and antimicrobial assessment

A multidisciplinary approach has been applied to the preparation of antibacterial Ag zeolite/silicone elastomer composites aimed at products that satisfy a range of requirements, namely good mechanical properties after zeolite incorporation and strongly antibacterial. Zeolite X was synthesised and used as antibacterial agent after ion-exchange with silver. The high level of silver (14 wt%) within the zeolite enabled the preparation of antibacterial composites containing a relatively low level of zeolite (2 wt%). The composites showed strong efficacy against Escherichia coli and Staphylococcus epidermidis. Organic functionalization of the zeolite with organo-silanes prior blending with the matrix usefully improved composite mechanical properties and reduced color development in Ag zeolite containing silicone elastomers. Organo-silane modification did not substantially affect the antibacterial performance of the materials; the number of viable cells of both Gram-positive and Gram-negative bacteria was reduced to beyond detection limits within 24 hours of incubation. Efficacy of the Ag zeolite containing composites against the yeast Candida albicans was found to be substantially less than observed with the two bacteria. This study demonstrates that evaluation of polymer composites needs to be performed via a multidisciplinary approach in order to avoid compromising a particular aspect of the materials' design, characteristics or performance, including the use of reliable testing methods to determine the latter

Postnatal cerebellar development in a mouse

The cerebellum is a part of the central nervous system, which plays an important role in cognitive functions, discriminative sensibility, and the coordination of voluntary movements. Its development takes place in two stages: prenatal and postnatal. The cerebellar germ originates from the rhombic lip. There are two major groups of cells: glutamatergic and GABAergic neurons, which are generated at different spatial-temporal intervals. In the postnatal period, Purkinje cells and their synaptic contacts undergo the most significant development. Another key point is the formation of anchoring centers and the foliation of the brain.The cerebellum is a part of the central nervous system, which plays an important role in cognitive functions, discriminative sensibility, and the coordination of voluntary movements. Its development takes place in two stages: prenatal and postnatal. The cerebellar germ originates from the rhombic lip. There are two major groups of cells: glutamatergic and GABAergic neurons, which are generated at different spatial-temporal intervals. In the postnatal period, Purkinje cells and their synaptic contacts undergo the most significant development. Another key point is the formation of anchoring centers and the foliation of the brain