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The problem of obtaining metal nanoparticles considering environmental risks in connection with the use of synthesis products in mixtures of new types of diesel fuel has been studied. An analysis of existing research on these topics was carried out. Based on the data sets obtained using the Dimensions and OpenAlex services, the characteristics of the studies were determined. To analyze the problem of green synthesis of nanoparticles, a dataset of 6,062 journal articles published from 2001 to October 2023 was used. The use of nanoparticles as diesel fuel components was investigated using a dataset of 540 journal articles published from 2005 to October 2023. The leading countries and organizations by the number of publications and citations have been identified. Based on the analysis of coauthorship, the issue of international cooperation is considered. The most significant publications were determined by the number of citations. Using methods of visual analysis of data on research keywords, their trends and prospects were determined. In addition, an assessment was made of the development of the problem of using “green” methods for obtaining nanoparticles used as components of diesel fuel.

The problem of obtaining copper-containing nanoparticles by chemical reduction has been studied. A comparison is made of traditional and “green” approaches to synthesis. The experimental data obtained during the synthesis of copper nanoparticles in the presence of a polymer stabilizer (polyvinylpyrrolidone) and a reducing agent (tert-butylamine-borane), as well as literature data on the synthesis of nanoparticles using plant and conditionally “green” substances (glucose, extracts of Ocimum sanctum and Celastrus paniculatus leaves, Sarcostemma acidum stem). The advantages and disadvantages of these approaches are identified and discussed. It is noted that the industrial applicability of “green” methods is limited due to the need to create completely new production of reagents for synthesis. In addition, the application of green synthesis is difficult due to scalability and standardization issues. Environmental pollution associated with the production of plant extracts also requires additional assessment. It has been established that traditional synthesis methods remain relevant for modern industry, and “green” methods have prospects for use in the distant future.

A method of effective elimination and localization of oil spills using a composite sorbent has been developed. The resulting material consists of polymer waste, mineral filler and surfactant. Due to the peculiarities of the method, the resulting sorbent allows the utilization of polymer waste and has a high oil capacity. The size of the sorbent can vary depending on the specified parameters, what simplifies storage and application.

In natural conditions, insertion of Agrobacterium T-DNA into the plant genome and its subsequent transfer via sexual reproduction has been shown for several dozens of species, including species from genera Nicotiana and Vaccinium. In the framework of investigation of possible function of cT-DNA in naturally transgenic species we have shown, that increasing of expression of rolC in Nicotiana tabacum is associated with increase of amount of glucose and total sugar content. Similar trend was observed for rolB/C-like gene in Vaccinium.

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This paper explores the image of a public servant of the Russian Federation whose qualities affect the opinion of population about public servants, public service, and the state in general. The paper is based on the results of sociological surveys and is aimed at answering the question whether professionalism is a system-building element in the image of a public servant, what other qualities create this image and how these qualities correlate with the qualities chosen by future public servants - students specializing in state and municipal management. The surveys have been conducted in two Russian cities (Moscow and Langepas (Khanty-Mansi autonomous district)). Participants of the Langepas survey were residents of the city, and those of the Moscow survey were residents of Moscow, respectively, including a group of first-year students specializing in state and municipal management. The data analysis has shown that professionalism based on continuous improvement of knowledge and skills is the system-building element in the image of a public servant. Moreover, the leading motive of professional activity is social and state benefit and the professional activity of a public servant is a necessity. The authority of a public servant depends on his activities and affects the authority of the state. [ABSTRACT FROM AUTHOR]

The article provides an analysis of use of heavy-duty gear trains in the mining industry. It was revealed that it is necessary to create a dynamic model to calculate the acting stresses and durability in order to assess the dynamic parameters of the gear train. The article provides the results of use of Nastran software shell in terms of stress-strain behavior of the girth gear. [ABSTRACT FROM AUTHOR]

Biphonation (two independent fundamental frequencies in a call spectrum) represents one of the most widespread nonlinear phenomena in mammalian vocalizations. Recently, the structure of biphonations was described in detail; however, their functions are poorly understood. For the dhole ( Cuon alpinus), biphonic calls represent a prominent feature of vocal activity. In this species, the biphonic call is composed of two frequency components – the high-frequency squeak and the low-frequency yap, which also occur alone as separate calls. In this study, we test the hypothesis that the complication of call structure, resulting from the joining of these calls into the biphonic yap–squeak may enhance the potential for individual recognition in the dhole. We randomly selected for analysis 30 high-frequency squeaks, 30 low-frequency yaps and 30 biphonic yap–squeaks per animal from five subadult captive dholes (450 calls in total). Discriminant analysis, based on 10 squeak parameter values, showed 80.7% correct assignment to a predicted individual. For 10 yap parameters, the correct assignment was only 44.7%. However, the analysis based on 10 parameters of the biphonic yap–squeak, selected as best contributing to discrimination, showed 96.7% correct assignment to a predicted individual. The results provide strong support for the hypothesis tested showing that the joining of two independent calls into a common vocalization may function to enhance individual recognition in the dhole. [ABSTRACT FROM AUTHOR]