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The former polarization of financial theorists regarding the importance of money is characteristic more than a decade confrontation monetarist and Keynesians, theirs long - term debate and opposition thesis " money it's not important " and " just is Money important ", The last two decades of the twentieth century are characteristic of the official common house thesis that " money it is important " The justification for the need for a theoretical analysis in this work and today is found in the fact that contemporary macroeconomic theory recognizes the end of radical anti-Keynesianism and at the same time the end of the intellectual monopoly of the dominant neoliberal doctrine that logically relies on and/or emerges from it, namely monetarism and all later theoretical derivatives. On the other hand, the goal of this work is not to reach the possibility of formulating new theoretical propositions, but rather to review the conflicting positions of representatives of different doctrines in financial theory to see current problems and controversies, and possibly still unresolved dilemmas, both in financial theory and in the management of monetary policy. and fiscal policies. in the world and here too.

We report on the synthesis of Pb[ChCN]2 (Ch = O, S, Se) and Pb[SeCN][OH] and their hitherto unknown crystal structures. All products were fully characterized by single-crystal and powder X-ray diffraction. Bulk analysis was performed by Rietveld refinement, elemental analysis, differential scanning calorimetry– thermogravimetric analysis (DSC–TGA), and solid-state Raman spectroscopy. Quantum-mechanical calculations based on the density functional theory allowed optimization of the structural parameters of these lead-based compounds, as well as assessment of their electronic structures and detailed assignment and interpretation of the vibrational spectra. In addition, the origin of bands related to difficulties in assigning the exact position of H atoms in the structures was resolved. [ABSTRACT FROM AUTHOR]

Materials with simultaneously excellent electrical conductivity (σ) and a high Seebeck coefficient (S) are important for thermoelectric applications. However, obtaining such materials is a challenging task as σ and S vary inversely with respect to each other. Here, a new fabrication process has been demonstrated that produces composite materials with desired properties. Electrically highly conducting copper sulphide (CuS) particles are encapsulated within a compound with a high Seebeck coefficient, i.e. copper iodide (CuI), to form core–shell type composites. The presented results show that the concept of producing such composites allows the optimisation of both σ and S to provide enhanced thermoelectric performance (measured using the figure of merit, zT) when compared to the individual starting materials. Quantum mechanical calculations are performed to elaborate on the Schottky barrier formed at the interface between copper iodide and copper sulphide and elucidate aspects of the improved transport mechanism. Furthermore, an optimized compositional ratio between the respective composite parts is identified, which at the same time exhibits a high power factor and reduced thermal conductivity. As a result, an improved value of 0.46 at room temperature has been observed, demonstrating that these simple, abundant, and non-toxic CuS/CuI composites are attractive candidates for thermoelectrics. [ABSTRACT FROM AUTHOR]

Copyright of Structural Integrity & Life / Integritet i vek Konstrukcija is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Calcium carbonates are critical in biomineralization processes and as functional materials. For many applications, isotope enrichment in these materials allows researchers to monitor reaction pathways and retrace environmental signatures. When using vibrational spectroscopy, isotopic composition is currently derived by summing the concentration of each isotopologue, assumed to be directly obtainable from the band intensity, divided by the content of the isotope within the different isotopologues (e.g., C16O3, C16O218O, C16O18O2 and C18O3). However, this approach relies on the assumption that each isotopologue band has an equivalent intensity when present at the same concentration within the crystal structure. Here, using a joint experimental and theoretical approach we test the spectral behavior of the O-isotopologues by examining the effect of a key isotopic tracer, 18O, on the vibrational spectra of the calcium carbonate phases calcite and vaterite. We demonstrate that isotopic substitution changes both band positions and band intensities to different extents, depending on the vibrational spectroscopy method used and the bands examined. For calcite, the υ1 symmetrical stretching Raman-active bands related to individual isotopologues are found to have very similar intensities and are not affected by changes in isotopologue distribution within the material. Fitting these bands resulted in a consistent underestimation of the isotopic enrichment of only 1%, thus they are expected to be useful for estimating 18O-enrichment extent in future experimental work. In contrast, vaterite vibrational bands change more extensively and thus cannot be used directly to determine the 18O concentration within the material. These results are expected to contribute to a deeper und less ambiguous understanding of evaluating isotopic enrichment effects in the vibrational spectra of calcium carbonates. [ABSTRACT FROM AUTHOR]

Within this paper is described an analytical model for the analysis of quasistatic load distribution in four contact ball bearings. The quasistatic model was developed on the basis of the static model, applying Hertz's theory of contact and John-Harris's load distribution on ball. In this paper, the model is extended by introducing parameters such as positive/negative clearances into static equilibrium equations. Behavior analysis of the four point contact ball bearing (FKL LSQFR 308) was performed for different operating conditions. Within certain analyzes, the analysis of the influence of conceptual parameters (positive/negative clearances) on the operational characteristics of bearings was performed. The change in external load also varied. Verification of the static behavior of the ball bearing LSQFR 308 was performed by comparing the results obtained by quasistatic modeling and the results obtained using the finite element method. [ABSTRACT FROM AUTHOR]

Within the universal motor helical gear reducer, single row deep groove ball bearings are usually used, but for larger driver dimensions and heavily loaded shafts, spherical roller bearings are used. In order to achieve the maximum load capacity of the gearbox, within the same axis height, relatively large single-row ball bearings are necessary. In some cases, due to dimensions constraints, they cannot be installed in the gearbox, so many manufacturers, in certain cases, use somewhat smaller and more expensive single-row cylindrical roller bearings. Though these bearings are not specifically designed to transmit axial forces, they can bear axial loads. The idea of this paper is to point out this problem and the benefits that come from the use of cylindrical roller bearings. [ABSTRACT FROM AUTHOR]

Copyright of New Economist / Novi Ekonomist is the property of University of East Sarajevo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Photocatalysis, a promising solution to environmental challenges, relies on the generation and utilization of photogenerated charge carriers within photocatalysts. However, the recombination of these carriers often limits efficiency. Heterostructures, especially Cu 2 O/TiO 2 , have emerged as effective solutions to enhance charge separation. This study systematically explores the effect of interfacial morphologies on the band bending within Cu 2 O/TiO 2 anatase heterostructures by employing density functional theory. Through this study, eight distinct interfaces are identified and analyzed, revealing a consistent staggered-type band alignment. Despite variations in band edge positions, systematic charge transfer from Cu 2 O to TiO 2 is observed across all interfaces. The proposed band bending configurations would suggest enhanced charge separation and photocatalytic activity under ultraviolet illumination due to a Z -scheme configuration. This theoretical investigation provides valuable insights into the interplay between interfacial morphology, band bending, and charge transfer for advancing the understanding of fundamental electronic mechanisms in heterostructures.

Metal sulphides, including zinc sulphide (ZnS), are semiconductor photocatalysts that have been investigated for the photocatalytic degradation of organic pollutants as well as their activity during the hydrogen evolution reaction and water splitting. However, devising ZnS photocatalysts with a high overall quantum efficiency has been a challenge due to the rapid recombination rates of charge carriers. Various strategies, including the control of size and morphology of ZnS nanoparticles, have been proposed to overcome these drawbacks. In this work, ZnS samples with different morphologies were prepared from zinc and sulphur powders via a facile hydrothermal method by varying the amount of sodium borohydride used as a reducing agent. The structural properties of the ZnS nanoparticles were analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques. All-electron hybrid density functional theory calculations were employed to elucidate the effect of sulphur and zinc vacancies occurring in the bulk as well as (220) surface on the overall electronic properties and absorption of ZnS. Considerable differences in the defect level positions were observed between the bulk and surface of ZnS while the adsorption of NaBH 4 was found to be highly favourable but without any significant effect on the band gap of ZnS. The photocatalytic activity of ZnS was evaluated for the degradation of rhodamine B dye under UV irradiation and hydrogen generation from water. The ZnS nanoparticles photo-catalytically degraded Rhodamine B dye effectively, with the sample containing 0.01 mol NaBH 4 being the most efficient. The samples also showed activity for hydrogen evolution, but with less H 2 produced compared to when untreated samples of ZnS were used. These findings suggest that ZnS nanoparticles are effective photocatalysts for the degradation of rhodamine B dyes as well as the hydrogen evolution, but rapid recombination of charge carriers remains a factor that needs future optimization., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Amakali, Živković, Warwick, Jones, Dunnill, Daniel, Uahengo, Mitchell, Dzade and de Leeuw.)