This paper is the latest contribution to a sequence of studies aiming to replace collapses resulting from measurements by spontaneous collapses [1-2]. The aim of Time Dependent Perturbation Theory (TDPT) is to calculate the transition probability between stationary states induced by a time dependent perturbation ([3], p. 168). Processes supposedly spontaneous, such as absorption and emission of radiation, radioactive decay and chemical reactions, involve transitions between stationary states. We have shown that in the framework of Orthodox Quantum Mechanics (OQM) transitions between stationary states require collapses, in turn requiring measurements. Hence, they cannot be considered spontaneous processes [1-2]. To solve this problem we assume that collapses necessary to yield transitions between stationary states are not the result of measurements but of a tendency of the system to jump into some states called preferred states. We suggest a modification of the formalism of OQM where the concept of preferred states plays a paramount role. The resulting theory is named Theory of Spontaneous Collapses Induced by a Time Dependent Perturbation (SCSS). Differing from other theories of spontaneous collapses [4], it is in compliance with the statistical meaning of conservation of energy.

Substantial part of the recent progress in deeper understanding the properties of zeolites, their active sites, defects, interactions with guest species, as well as their sorption and catalytic behavior was done with coherent contributions from experimental studies and computational modeling based on quantum chemical methods. The significant progress of computational resources allowed simulations to approach complexity of real systems. 

The first topic is connected with the interpretation of experimental spectral features and acidity of OH groups in zeolites as well as the interplay between silanols and bridging hydroxyls. An advantage of our modeling is that one has consistent information about the spectral and structural features of each individual OH group. In this way we derived correlations of the calculated ¹H NMR chemical shifts and stretching O-H vibrational frequencies with the formed H-bonds [1]. The calculated acidity of the hydroxyl groups is found to be in the range of super acids in the gas phase, but it does not correlate with the NMR or IR spectral features [2].

The second topic is related to location of germanium centers in germanosilicate zeolite and influence of the template on it based on the relative stability of the structures. The results suggested that in the studied zeolite germanium centers tend to cluster in part of the double four rings, while other double four rings are composed only by silicon T atoms for both SCM-14 [3] and SCM-15 [4] structures. The simulations also clarified that the influence of the OSDA on the germanium distribution is strong and for SCM-15 the presence of OSDA even alters the stability order of the structures with different germanium distribution [5]. The research is supported by Bulgarian Science Fund, contract № КП-06-ДВ-2/16.12.2024.

Copper oxide (CuO) has emerged as a promising candidate for chemiresistive gas sensors due to its intrinsic p-type semiconducting nature, cost-effectiveness, and strong interaction with a wide range of toxic and volatile organic compounds. In this study, density functional theory (DFT) was employed to investigate the adsorption behavior of various gas molecules, including NO, NO₂, CO, CH₂O, ethanol, and acetone, on the CuO (111) surface.The adsorption energies revealed a clear trend in gas-surface interactions: NO exhibited the strongest binding (-2.96 eV), followed by CO (-2.34 eV), acetone (-1.90 eV), ethanol (-1.755 eV), formaldehyde (-0.471 eV), and NO₂ (-0.107 eV). Structural analysis of adsorption configurations indicated distinct bonding motifs and charge redistribution pathways that correlate with adsorption strength. Strong chemisorption was observed for NO and CO, while weaker physisorption dominated for NO₂ and formaldehyde.These findings provide fundamental insights into the selectivity and sensitivity of CuO-based gas sensors, highlighting NO and CO as the most responsive analytes. The study demonstrates that theoretical modeling can serve as a predictive tool for screening gas–sensor interactions, guiding the rational design of next-generation CuO-based sensing devices for environmental and health monitoring.

There are numerous aspects in the mathematical modeling of vacuum spacetime in Cosmology. Gravitation and electromagnetism are the two actions-at-distance phenomenological fields occurring in a vacuum (without mediating matter with infinite radius).  Nowadays, since the works of Permutter et al. [1] and Riess et al. [2], one of the biggest challenges in cosmology is to understand the physics behind the acceleration of the universe expansion, assumed to be due to an unknown dark energy and also the Universe missing mass assumed to be a dark matter required for maintaining the whole Universe. The Cosmological Constant was classically introduced ad hoc to explain the dark energy. 

The main motivation of the present paper is to develop a mathematical model of Generalized Continuum for analyzing the link between spacetime continuum, gravitation and electromagnetism with the only necessary three phenomenological fields on vacuum spacetime by avoiding micro-particles physics and cosmological fluids, despite their preeminent role in cosmology. The main application is to attempt to explain the concept of dark energy and dark matter. The work rather focuses only on phenomenological fields occurring in a vacuum Universe as a continuum. 

The present paper is based some fundamental assumptions to define the geometrical background of a Generalized Continuum model and the physical events occurring within it [3] : (1) the spacetime has a structure of differentiable four-dimensional manifold endowed with a metric, and independent connection with torsion; (2) only gravitation and electromagnetism are considered as physical fields, since they are the only actions-at-distance among the four universal fundamental forces [4]. The action is composed of the Einstein-Hilbert-Palatini (for gravitation) and Yang-Mills (for electromagnetism) Lagrangians.

The general methodology consists of exploiting the geometric structure of spacetime continuum by reminding Riemann and developing Riemann-Cartan manifolds. Accounting for the torsion field in addition to macroscopic deformation (metric and strain) was inspired from the work of Rainich (1925) [5] and Misner & Wheeler (1957) [6] by adding the property of multiply-connectedness to usual Riemann manifold in the framework of continuum mechanics. These two works were themselves inspired by the works of V. Volterra on dislocations and disclinations (1901) [7]. 

The idea is to reduce the phenomena of gravitation and electromagnetism to the geometric variables  as curvature and torsion fields on the continuum. Torsion will be a matter of concern all along this work, and implicitly we show that spacetime is more and more assimilated to an infinitely small sets of microcosms, as due to brusque cooling of the Universe at the beginning. Mathematical models extending the usual framework for field equation in classical continuum mechanics are developed within the Einstein-Cartan geometric background [8]. 

For the application in Cosmology, the introduction of an ad hoc hypothetical Cosmological Constant is no more necessary as shown by our results. Models nevertheless show the presence of non homogeneous and anisotropic fields definitely replacing an hypothetical Cosmological Constant. 

In sum, only electromagnetic and gravitational fields coupled with Generalized Continuum model might be sufficient to describe dark energy and by the way dark matter by means of the torsion field of the vacuum spacetime [8]. 

Zeolites as inorganic highly crystalline materials possess high hydrothermal stability even at high temperatures. Due to their microporosity, they exhibit selectivity for various reactions, including cracking and isomerization [1].In order to expand the possibilities for their application, there is interest in zeolites with extremely large pores. A recent notable discovery in the field of zeolite synthesis is the extremely large-pore size above 20 A⁰ aluminosilicate zeolite, ZMQ-1, achieved directly by synthesis using a quaternary phosphonium salt [2]. It exhibits robust hydrothermal stability during calcination and template removal under atmospheric conditions.

In order to obtain suitable templates for the synthesis of large-pore zeolites, we synthesized a series of phosphorus-containing coumarin derivatives [3]. In the present study an approach for synthesis of 3,3’-biscoumarins have been presented. Two types of coumarinphosphonium salts were applied as appropriate precursors for in situ generated ylides for Wittig olefination with aromatic aldehydes or coumarin carbaldehydes. In the present study an approach for synthesis of 3,3’-biscoumarins have been presented. Two types of coumarinphosphonium salts were applied as appropriate precursors for in situ generated ylides for Wittig olefination with aromatic aldehydes or coumarin carbaldehydes. The preferred stereochemistry of the formed π-bond between the two coumarin fragments has characterized as trans (E)-configuration in the obtained compounds. Several styryl coumarins containing phosphonic substituents in the lactone ring and suitable modification groups in the benzene ring have been prepared. Initial studies on their application as templates are in progress.R.N. acknowledge the European Union—NextGenerationEU, through the National Recovery and Resilience Plan of the Republic of Bulgaria, project No BG-RRP-2.004-0008.

The production of quality castings requires the use of modern computer programs that serve to simulate foundry processes as a tool for optimizing proposed production technologies. This paper focuses on the analysis of a computer simulation concerning the casting of a brake disc at a Slovak foundry. Notably, this brake disc has experienced issues such as shrinkages and micro shrinkages, which adversely affect the internal quality of the casting. Through this study, we aim to enhance our understanding of these challenges and explore solutions to improve the overall quality of cast components, making the process more efficient and cost-effective. Defects were identified in the ribs located in the upper section of the casting beneath the feeders. To address this issue, a comprehensive computer simulation was conducted, replicating the actual conditions of the casting and solidification process. The results revealed that the initially designed gating system, along with its feeder configuration, was inadequate in preventing the formation of these defects. 

In response, a new feeder layout was proposed, which successfully eliminated the defects based on the simulation outcomes. The input parameters for this simulation were meticulously set to reflect the actual requirements of the foundry closely. To facilitate this process, 3D models of the assemblies were created using SolidWorks CAD software, and filling and solidification simulations were carried out using the NovaFlow & Solid CV 4.6r42 simulation program. This approach ensured a thorough analysis and resolution of the issues at hand.