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The transport system of megalopolises is structured quite complex and it is not easy to decide on criteria of rational organization of transport services. The urban public transport services are to be improved through a more rational distribution of its resources. The article describes the idea of introducing and developing the project "City train" to improve the life of a contemporary city. The experience of different cities all over the world has been studied and summarized. It has been proven that the project has not lost its relevance to be realized in a post-pandemic city. The criteria of traffic convenience and transport availability and their impact on the population life quality are considered. The urban public transport services in Yekaterinburg are analyzed. A model is proposed to calculate the average time of a passenger's movement around the city, using a city train. The time saved when changing the road map of passengers is determined. The economic efficiency of the project is calculated based on the determination of the cost of labor resources and taking into account the gross regional product. [ABSTRACT FROM AUTHOR]

This work is devoted to the study of alkaline earth elements sorption by a MnO2-MN202 sorbent with the focus on radium separation from natural water in analytical methods. The sorbent consisted of manganese dioxide layer coated onto the surface of a macroporous organic support. The paper presents the data on the conditions for the synthesis of the sorbent and the results of experiments on the sorption of alkaline earth elements from aqueous solutions. The chemical yield of radium was 87 % after passing 1-L spiked water sample through the column followed by desorption by 1 M HCl. [ABSTRACT FROM AUTHOR]

The unique urban forests of Almaty, being part of the Ile-Alatau National Park, have the highest not only ecological, but also recreational value, which often causes their degradation. There are many rare and endemic species in the forests. Relic forests of Schrenk spruce, unique mountain deciduous and fruit forests, including relict forests dominated by Sievers apple trees, apricots, carcasses, whose areas have significantly decreased over the past century, need special protection. To study the spatial distribution and dynamics of urban forests of different species composition for 2014-2020, remote sensing methods, geoinformation analysis, mapping, statistical methods implemented by GIS tools were used. Forest inventory materials, Landsat-8 and Sentinel-2 images were involved. Two maps have been constructed showing the distribution of heterogeneous forests in 2014 and 2020. For quantitative assessments, algorithms for statistical processing of the attributes of the obtained vector layers in the GIS environment were used. The calculations showed that the main areas in the south of the study area are occupied by spruce forests (54%), in the north - by apple forests (16%). The latter are located within transport accessibility from residential areas of the city and are under ever-increasing anthropogenic load. It is shown that, in general, the areas of urban forests, due to the conservation status, have decreased slightly. However, the most valuable spruce and apple forests are characterized by the greatest losses, and to a lesser extent, poplar-aspen forests. The greatest losses of spruce forests were noted in the basins of the Malaya Almatinka and Kumbel rivers, apple forests - in the Esentai river basin. [ABSTRACT FROM AUTHOR]

The development of the North requires adaptation to the Arctic specifics of the territory. First of all, this concerns areas of active development and transportation of hydrocarbons. Using the Bolshezemelskaya tundra as an example, the article presents the results of assessing the possibility of using cryogels in the conditions of permafrost distribution. The use of cryogels, which are a modern composite eco-friendly material with adjustable properties, can help minimize the negative anthropogenic impact on the environment, reduce technogenic risks and economic costs, and ensure environmental safety. It is shown that the frequency of occurrence of natural and technogenic situations, the solution of which is possible with the use of cryogels, depends on the morphological structure of landscapes in the permafrost zone. The most common natural-anthropogenic situations in which the use of cryogels is possible are identified. The permafrost-landscape prerequisites for the spread of such situations are determined. The index "Cryogels application potential" was calculated separately for each type of zonal landscapes, taking into account geomorphological levels. It was revealed that the potential for the use of cryogels is very high, and the areas of their possible use vary greatly depending on the zonal belonging of the development site, increasing to the north. An analysis of the variability of the potential for the use of cryogels showed that with a decrease in the absolute elevations of the landscape surface, the following trends are revealed: a) its increase for situations of stabilization and increase in the bearing capacity of soil foundations of objects, prevention of exogenous processes, optimization of the filtration properties of soils of natural and technical systems, formation of a heat-insulating screen, reclamation of disturbed areas in the northern taiga; b) its decrease with the development of solifluction processes and the reclamation of disturbed areas in the forest-tundra and tundra. [ABSTRACT FROM AUTHOR]

The study conducted in the State Nature Reserve "Bylina" (Kirov region, Russia) revealed 377 species of macrofungi, 19 out of which are considered rare, few are included in the Red Book of Russian Federation and/or the Red Book of Kirov region: Sarcosoma globosum, Skeletocutis odora, Clavariadelphus pistillaris. Several indicator species of aphyllophoroid fungi found in old undisturbed forests predominantly on large fallen dead-wood were marked within the investigated territory which confirms the status of the protected area; these are: Amylocystis lapponica, Antrodia albobrunnea, Asterodon ferruginosus, Ceriporia violacea, Cystostereum murrayi, Dichostereum granulosum, Diplomitoporus crustulinus, D. flavescens, Fuscopostia fragilis, Gloeophyllum abietinum, Junghuhnia collabens, Meruliopsis taxicola, Neoantrodia infirma, Phellinidium ferrugineofuscum, Physisporinus crocatus, Poriella subacida, Pycnoporellus fulgens, and Skeletocutis odora. [ABSTRACT FROM AUTHOR]

The initial prestress of the reinforcement does not remain constant, but already during the manufacturing process (when the reinforcement is tensioned), and also decreases over time due to losses caused by the physical and mechanical properties of concrete and reinforcement, the technology of manufacturing structures and elements. When tensioning the reinforcement on the stops, one distinguishes between the first losses occurring during the tension of the reinforcement (due to the relaxation of steel stresses; the temperature difference between the tensioned reinforcement and the device that perceives the tension forces; deformations of steel forms and anchors of the tensioning devices), and the second losses occurring after compression and increasing in the process operation of the structure (from shrinkage and creep of concrete). The article provides a rationale for the proposed methodology for the practical calculation of prestressing losses in reinforcement from shrinkage and creep of concrete at an arbitrary time of storage of reinforced concrete structures. In a numerical experiment, the optimal parameters of the calculation formulas of the proposed method are revealed. [ABSTRACT FROM AUTHOR]

The kinetics of rare earth elements leaching from phosphogypsum, a waste product from the extraction of phosphoric acid by sulfuric acid scheme of apatite processing, was studied. It was determined that the kinetics was limited both by the rate of the chemical reaction in the initial period of time and by internal diffusion during further leaching. Mechanical activation as a method to intensify the extraction of REE was investigated and allowed to reduce the apparent activation energy of the process by 30 %. [ABSTRACT FROM AUTHOR]

An overview of brief anthology and prospects of the novel, N3-phenacyluridine-derived hypnotics is presented, together with description of several new acyclonucleoside analogues of a kind. [ABSTRACT FROM AUTHOR]

The sorption of scandium and zirconium by weakly basic anion exchangers from sulfuric acid solutions was investigated. Anion exchanger with benzylamine functional group has a high sorption capacity for zirconium and relatively low sorption capacity for scandium, which makes it possible to use this sorbent to separate these elements. [ABSTRACT FROM AUTHOR]

One of the possible sources of scandium production - waste (slags) from processing of oxidized nickel ores, has been considered in present research work. The hydrometallurgical method has been selected as the primary for scandium extraction. Different reagents for leaching of scandium, such as sulfuric acid, various carbonate salts and fluorides, have been tested. Sulfuric acid has been recognized as an optimal leaching reagent. Sulfuric acid concentration of 100 g L-1 allowed recovering up to 97 % of scandium. [ABSTRACT FROM AUTHOR]

Batch testing and determination of appropriate biosorbent and experimental procedures for recovery of REEs from artificial solution as well as the efficiency of the process for recovery of REEs from artificial solution via biosorption are given in present research work. [ABSTRACT FROM AUTHOR]

A comparative study of rare earth, ferric and aluminum ions ion exchange behavior on gel sulfonated polystyrene cation exchange resins depending on the degree of the matrix cross-linking and pH of the solution is presented. Selective ion exchange of REEs is possible at the pH range of 1.5-2.0 using strongly acidic cation exchange resins containing more than 8% of DVB. The preliminary results of testing the efficiency of REEs recovery from the industrial uranium underground leaching solutions are also presented. [ABSTRACT FROM AUTHOR]