The great prospects for introducing the cold sintering process (CSP) into industry determine the importance of finding approaches to reduce the processing time and mechanical pressure required to ...obtain dense ceramics using CSP. The introducing zinc acetate into the initial ZnO powder of methods, such as impregnation, thermovapor autoclave treatment (TVT), and direct injection of an aqueous solution into a die followed by cold sintering process using a spark plasma sintering unit, was studied. The effect of the introduction methods on the density and grain size of sintered ceramics was analyzed using SEM, dynamic light scattering, IR spectroscopy, and XRD. The impregnation method provides sintered samples with high relative density (over 0.90) and significant grain growth when sintered at 250 °C with a high heating rate of 100 °C/min, under a uniaxial pressure of 80 MPa in a vacuum, and a short isothermic dwell time (5 min). The TVT and aqueous solution direct injection methods showed lower relative densities (0.87 and 0.76, respectively) of CSP ZnO samples. Finally, the development of ideas about the processes occurring in an aqueous medium with CSP and TVT, which are subject to mechanical pressure, is presented.
The article considers “digital twins” of the population as a tool for socio-demographic research and territorial management. The experience of creating digital twins of the population and interactive ...web-sites devoted to demographic issues is systematized. A methodology for creating a digital twin of the Arctic population is proposed, based on three methodological principles: consideration of the hierarchy of territories, spatial representation of data, and combining demographic statistics with new digital data sources. The author has developed the Digital twin of the Arctic population — an interactive website (dashboard) containing detailed data on the Arctic population, including municipal and settlement levels. It includes demographic statistics, census results and data from digital platforms. The Digital twin of the Arctic population covers such issues as the size, dynamics and composition of the population, resettlement, natural and migration movement, labor and employment, transport movements, science and education, and the impact of the pandemic on demographic processes. Tools of ranking, multivariate analysis, clustering and forecasting of indicator values are implemented for researchers. From the viewpoint of state and municipal management, the main interest is the demographic profiles of regions and territories, reflecting up-to-date information about the demographic situation. Using the Digital twin of the Arctic population, the author draws conclusions about the spatial patterns of the demographic development of the Russian Arctic.
We define quantum equivariant K-theory of Nakajima quiver varieties. We discuss type A in detail as well as its connections with quantum XXZ spin chains and trigonometric Ruijsenaars-Schneider ...models. Finally we study a limit which produces a K-theoretic version of results of Givental and Kim, connecting quantum geometry of flag varieties and Toda lattice.
The influence of the method of applying the activating additive ammonium chloride and its concentration on the density and microstructure of zinc oxide ceramic obtained by cold sintering at 244 °C ...was investigated. The activating agent was applied by two methods: impregnation and subsequent autoclave treatment. When the powder was activated by the impregnation method, the crystal sizes remained at the initial level of 0.17-0.19 μm. After the autoclave treatment, the crystal sizes increased to 0.31-0.53 μm. Samples of cold sintering ZnO with relative density up to 0.96 and average grain sizes 0.29-0.86 μm were obtained. ZnO powders and ceramic samples were analyzed using SEM, TGA/DSC, and XRD to reveal the effect of the powder activation method and cold sintering conditions on the material microstructure. The effect of ammonium chloride concentration on grain growth and microstructure of ceramic samples is shown. It was found that the average grain size of ceramic samples with an increase in additive concentration passes through a minimum. In cold sintering of the autoclave activated powder, the effect of reducing the average grain size was observed. The results of this work are discussed on the basis of the idea of the solid-phase mobility of the crystal structure arising when interacting with an aqueous medium.
The process of formation of a Langmuir–Schaefer (LS) matrix based on a mixed monolayer of arachidic acid (AA) and 8 nm CdSe/CdS/ZnS quantum dots (QDs) stabilized by molecules of trioctylphosphine ...oxide (TOPO) was investigated. The change in the morphology, monolayer compressibility, and area per elementary cell of the created mixed monolayers, depending on the ratio of the components, was studied. It is shown that the change in the morphology of Langmuir–Blodgett (LB) monolayers begins to occur at a ratio between the number of QDs and AA molecules of 1:24. Dendrimeric structures with a thickness of the order of 30–40 nm appear in the mixed monolayer when LB film deposition was carried out above the collapse surface pressure of a Langmuir film from only TOPO-covered QDs. Information on the dependence of the morphology of such structures on the molar ratio of the components is necessary for the production of ordered 2D nanostructures containing 0D and 1D objects with quantum bonds. Such nanostructures can be used in nanoelectronic and optoelectronic devices as a sensitive sensor element. The obtained results would be relevant for any type of spherical shape nanoparticles.
Optical Sensors for Bacterial Detection Guliy, Olga I; Karavaeva, Olga A; Smirnov, Andrey V ...
Sensors (Basel, Switzerland),
2023-Nov-24, Letnik:
23, Številka:
23
Journal Article
Recenzirano
Odprti dostop
Analytical devices for bacterial detection are an integral part of modern laboratory medicine, as they permit the early diagnosis of diseases and their timely treatment. Therefore, special attention ...is directed to the development of and improvements in monitoring and diagnostic methods, including biosensor-based ones. A promising direction in the development of bacterial detection methods is optical sensor systems based on colorimetric and fluorescence techniques, the surface plasmon resonance, and the measurement of orientational effects. This review shows the detecting capabilities of these systems and the promise of electro-optical analysis for bacterial detection. It also discusses the advantages and disadvantages of optical sensor systems and the prospects for their further improvement.
The aim of this article is to establish a link between the current social reality in Russia and the strictly theoretical challenges facing philosophy. The past 30 years have seen a marked change in ...relations between philosophy and society. In 1991, ideological restrictions, including in the field of philosophy, were lifted. As a result, Russian philosophy has focused mainly on eliminating its lag behind Western philosophy. This vector of development resulted in a disconnect between philosophy and society, the individual consciousness of philosophers and public consciousness. Formulating and accepting a valid epistemological grounding for the Russian civilization project equal in scale to the Western one became a pressing task of contemporary philosophical thought in Russia. This project calls for a new and more universal solution that would bring together disparate value systems existing in Russian society. This requires a huge philosophical effort to develop individual philosophical consciousness and bring it to the level of genuine self-consciousness of philosophy and society. The language of Russian philosophy needs to be developed, and indeed, restructured, which is a distinct task and area of effort for the philosopher. Philosophy must come to grips with the issue of (non)universality of reason. For Russian culture, vsesubyektnost'-the Utopian ideal of indispensable and indissoluble tselostnosf and the indispensable and indissoluble diversity of all subjects (agents)-could become the basis of a way of thinking that is entirely independent of European thought. This idea-seen as a Utopia, when considering how it could serve as a basis for a big culture to develop a complete civilization system-offers a boundless field of work at all levels, from the basic one associated with the philosophy of mind to the highest levels of culture and civilization development.
Interactions between C accumulation, resulting from plant residue mulching, and the accelerated decomposition of litter and soil organic matter due to higher enzyme activities remain poorly ...understood, particularly in urban forests. Here, the activities of four enzymes associated with carbon (C) and nitrogen (N) cycling after organic mulching were investigated in the rhizosphere and bulk soil of a 15-year-old Ligustrum lucidum urban forest. The enzymatic activities in the rhizosphere were closely correlated to those in bulk soil, however, they were more strongly affected by organic mulching and exhibited faster C and nutrient cycling. Moreover, the activity of urease in the rhizosphere and peroxidase in the bulk soil in autumn, as well as invertase in the rhizosphere in spring, decreased. Microbial C and N were most responsible for the observed increase in invertase activity in spring, during which microorganisms exhibited rapid growth and the highest activities, whereas soil organic C regulated urease activity in winter. Additionally, the activity of dehydrogenase increased by up to 75%; the degree of increase was typically dependent on the mulching amount. Generally, invertase and dehydrogenase activity increased with the abundance of dissolved organic matter and microbial biomass, whereas peroxidase exhibited the opposite trend. Taken together, these findings indicate that organic mulching efficiently increases enzymatic activity, particularly within the rhizosphere, thus accelerating soil C and N cycling. Hence, mulching may represent an effective measure for urban forest management and soil conservation.
The article considers a theoretical model of digital society based on four concepts: super-connectivity, platformisation, datafication, and algorithmic governance. The model describes how the ...digitalisation of society deepens: from the transfer of individual practices and social interactions to a new social order based on big data. Analysis of panel data from the 2003–2018 longitudinal survey (RLMS HSE) and geospatial data from the 'Virtual population of Russia' project shows that, despite considerable growth in specific indicators, the digitalisation of the Russian society across various social groups, territories and areas of public life appears fragmented. Elimination of this disparity is primarily hindered by the low stability of an individual's online practices. Analysis of the national projects approved in 2018 helped assess the prospects of the digital society in Russia and identify barriers to public adaptation to the changes.
To evaluate the level of soluble endoglin (sEng) in pregnant women with pregestational diabetes mellitus (DM) and to assess its predictive value for preeclampsia development.
Ninety pregnant women ...were enrolled in the study forming five comparison groups: type 1 DM (not planned, n = 20; planned, n = 20), type 2 DM (diet, n = 15; insulin therapy, n = 20), and the control group (n = 15). The primary outcome was clinically confirmed preeclampsia. Maternal serum concentrations of sEng were measured at 11+0-13+6 and 30+0-33+6 weeks.
sEng level was elevated in all patients with pregestational DM compared to the control group. Its plasma concentration increased with gestational age and in case of preeclampsia development. In patients with type 1 DM, serum sEng level did not depend on the presence of preeclampsia. This is evidence of severe metabolic disorder and endothelial dysfunction in these patients. The addition of sEng level to logistic models considering established risk factors (body mass index + age + HbA1c level) in the first and third trimesters significantly improved their performance for preeclampsia prediction.
Eng level may become an important marker for early prediction of preeclampsia in women with pregestational DM.
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