Changes in the spectral characteristics of biological tissues depending on temperature

This work was aimed at determining the optical characteristics of biological samples at different temperatures. The work investigated the change in the intensity and shape of the absorption spectra of various biological tissues in vitro, depending on the sample temperature

Implementation of discussion technologies in a personality-centered professional education

The conditions of modern labor market dictate the need for highly qualified specialists who creatively approach the performance of their professional activities, independently making competent productive decisions. In search of a solution to this problem, higher education institutions resort to the use of modern educational technologies. The article presents the forms of implementation of discussion technologies, their peculiarity, considers their importance and specificity of use in the conditions of personality-centered training and defines the goals of discussion technologies implementation in the course study. The study revealed an increase in the level of students’ training. The use of discussion technologies allowed them to study the topics of the course more deeply

Application of the similarity theory to analysis of photocatalytic hydrogen production and photocurrent generation

In this research some methods of the similarity theory were quantitatively applied to the description of the relationship between the efficiencies of the photocatalytic hydrogen production and photocurrent generation for the first time. Two possible similarity criteria, namely, such as the ratio of the number of electrons involved in the photocatalytic reaction to the generation of photocurrent ones and the ratio of energies transformed in the case of photocatalytic hydrogen evolution to the photocurrent, were obtained by the dimensional analysis. The literature data allow checking the first criterion. The application of the first possible similarity criterion to the samples with different chemical nature, solid solutions, series, in which the synthesis time or the ratio of catalyst components, electrolyte amount or its nature is changed, was analyzed. It was shown that the ratio of electrons may serve as the similarity criterion only under the conditions of geometric and physical similarities

Studying effects of external conditions of electrochemical measurements on the photoelectrochemical properties of semiconductors: cyclic voltammetry, impedance spectroscopy, and Mott – Schottky method

In this paper, the dependences of the semiconductors’ photoelectrochemical properties on the experimental conditions were studied for the solid solution of CdS and ZnS, graphitic carbon nitride, and the platinized carbon nitride. The cyclic voltammograms were obtained under different scan rates. The sample investigations were carried out by two ways, at the constant external voltage and varied amplitudes and at different external voltages and the fixed amplitude. The Mott – Schottky dependences were studied at different frequencies. The basic dependences of the changes in the photoelectrode target characteristics on the experimental condition were found. Some recommendations for the correct comparison of qualitative and quantitative photoelectrochemical data were formulated.https://doi.org/10.15826/elmattech.2023.2.01

Greening of Regional Economic Systems within the Framework of Sustainable Development Goals

Sustainable development was chosen by the United Nations as the key concept of the future in the 21st century, which led to the emergence of other economic concepts, such as green and blue economy, seen as contributing to the achievement of sustainable development goals (SDGs). In Russia, despite the ongoing processes of green transformation in some economic sectors and certain improvements in the green legislation and green finance, not all businesses and regions are ready to embrace sustainable development. This paper discusses two interconnected aspects of regional economic systems — their economic efficiency and environmental impact. The analysis focuses on the regions of the Ural Federal District and explores these regions’ transition to sustainable development by looking at their eco-intensity. Methodologically, the study relies on the methods of analysis and synthesis, statistical, comparative and causal analysis. Conceptually, we use the theoretical framework of sustainable development as a point of departure for our discussion. The results have shown, on the one hand, a decrease in the industrial pressure on the natural environment, related primarily to the enhanced resource efficiency of certain industries. On the other hand, less effort is now invested into minimising the negative impact on the environment in Ural regions. We have also identified those areas of sustainable development that hold most promise in the Russian context. Our findings can serve as a basis for the strategies of regional sustainable development and may be used for further research on socio-environmental and economic sustainability

Greening of Regional Economic Systems within the Framework of Sustainable Development Goals

Sustainable development was chosen by the United Nations as the key concept of the future in the 21st century, which led to the emergence of other economic concepts, such as green and blue economy, seen as contributing to the achievement of sustainable development goals (SDGs). In Russia, despite the ongoing processes of green transformation in some economic sectors and certain improvements in the green legislation and green finance, not all businesses and regions are ready to embrace sustainable development. This paper discusses two interconnected aspects of regional economic systems — their economic efficiency and environmental impact. The analysis focuses on the regions of the Ural Federal District and explores these regions’ transition to sustainable development by looking at their eco-intensity. Methodologically, the study relies on the methods of analysis and synthesis, statistical, comparative and causal analysis. Conceptually, we use the theoretical framework of sustainable development as a point of departure for our discussion. The results have shown, on the one hand, a decrease in the industrial pressure on the natural environment, related primarily to the enhanced resource efficiency of certain industries. On the other hand, less effort is now invested into minimising the negative impact on the environment in Ural regions. We have also identified those areas of sustainable development that hold most promise in the Russian context. Our findings can serve as a basis for the strategies of regional sustainable development and may be used for further research on socio-environmental and economic sustainability

Revision of the total nitrogen and phosphorus content in a cattle manure-based organic fertiliser in North-West Russia

This study aimed to verify the applicability of a mass balance method for estimating nitrogen (N) and phosphorus (P) content in the solid organic fertiliser produced from cattle manure in North-West Russia. The study compared the relevant established norms in Russia, the data calculated by the mass balance method, and the average experimental data on N and P content in cattle manure (ex-housing) and the organic fertilizer ready to use from the selected cattle-breeding complex with 1250 heads and a manure output of 70 t day-1. Three animal categories were considered. The difference between the calculated and experimental data was 10% maximum but the experimental data and the established norms differed by above 15%. This proves the demand to revise the norms in the Russian regulatory documents to improve the accuracy of fertiliser application rates and the estimation of agricultural land required. Even an increase of 10% in the nutrient content of the organic fertiliser results in an increase in the required agricultural land from 451 to 526 ha for spreading the organic fertiliser from the 1250 heads of cattle at the selected farm

Influence of optimal conditions of ultrasonic dispersion on the stability of suspensions of finely ground slags

The preparation in the jet mill of finely ground slag (FGS) from the waste of metallurgical production granulated blast-furnace slag, the obtaining of slag suspensions, and the behavior of FGS particles in an aqueous dispersion medium are considered in the paper. It was found that FGS particles in the suspension form micelles of two types with negative (micelle 1) and positive (micelle 2) charges of FGS surface. To increase the aggregative and sedimentation stability of FGS particles in suspensions, studies were carried out using ultrasonic dispersion. The results of investigations on the detection of optimal dispersion parameters for slag suspensions are presented. It was found that in the absence of temperature control, the process of coagulation of slag particles is accelerated and aggregative and sedimentation stability of suspensions of FGS is reduced. The slag particles in the suspension form aggregates that lead to a deterioration of the strength characteristics of the cement stone using suspensions of FGS. Optimal parameters of ultrasonic dispersion of slag suspensions are established: the frequency of ultrasonic vibrations is equal to 44 kHz; the dispersion temperature is 25 ± 2 °C; the dispersion time is 15 min. It was found that the application of ultrasonic dispersion to slag suspensions with the observance of dispersion conditions can increase the aggregative and sedimentation stability of FGS suspension by 2-3 times in comparison with the mechanical mixing of suspensions. The strength of samples with suspensions of FGS prepared using UST under the recommended dispersing conditions increased by 19 to 39% in the first day; for 28 days of hardening - by 19 - 36%, which allows using slag suspensions in the production of cement composite materials and concretes based on them