This work fulfills two major aspirations of the last century: the duality of electromagnetism with the inherent magnetic monopole and the unification of gravity and electromagnetism. This leads to two important outcomes: two new previously unknown interactions and the conclusion that gravitational law is slightly different for elementary particles.

The (3 + 1)-dimensional combined pKP-BKP equation is comprehensively explored in this paper. First, N-solitons, breathers, and diverse mixed solutions made up of breathers and kink solitons are among the exact solutions of the (3 + 1)-dimensional combined pKP-BKP equation by using the Hirota bilinear method. Second, lump solutions are obtained from the long-wave limit of the N-solitons and soliton molecules are created through introducing new resonance conditions to the N-solitons. Subsequently, by offering a variety of semi-rational solutions, including lump solutions, kink solitons, and breathers, we enhance the analysis of the (3 + 1)-dimensional combined pKP-BKP equation. The dynamic behavior of these exact solutions is shown using density plots with contour lines and three-dimensional graphs.

The soliton solution in the term of (A, B, C) triplet matrix is obtained. The inverse scattering problem for integration of the matrix sine-Gordon equation with a source is applied. Also, the matrix sine-Gordon equation with a source, specifically, the source consists of the combination of the eigenfunctions of the corresponding eigenvalue problem for the matrix Zakharov-Shabat system is studied.

This study aims to improve the numerical solution of the two-dimensional Eikonal equation, a fundamental partial differential equation in wave propagation and geometric optics, by creating highly efficient and precise recursive schemes. These schemes enhance computational performance, reduce numerical complexity, and increase solution accuracy for essential applications in seismic imaging, computer vision, and robotic path planning. We propose two innovative recursive schemes that enhance an advanced adaptation of the modified decomposition method. These schemes break down the nonlinear Eikonal equation into manageable components, enabling robust iterative solutions. The methodology is rigorously derived and confirmed through extensive numerical simulations across various examples, featuring multiple boundary conditions and domain complexities. Results indicate that the proposed schemes surpass existing methods in terms of accuracy, stability for complex geometries, and computational efficiency, as shown by faster convergence rates, making them suitable for large-scale challenges in applied mathematics and engineering. This work introduces two novel recursive schemes, specifically designed for the Eikonal equation, which extend the modified decomposition method with innovative adaptations. These schemes offer a unique blend of simplicity, scalability, and durability, addressing the limitations of traditional methods and providing novel numerical algorithms and insights that greatly enhance the computational toolkit for tackling nonlinear partial differential equations in scientific and industrial applications contexts.

We shall present some facts relevant to solving the problems of polarization optics in the frames of Stokes's vector and Jones's spinor formalisms. It is known that the completely polarized light can be described by Stokes 4-dimensional vector or alternatively by Jones complex 2-dimensional spinor. It is known that the Stokes formalism may be extended to a partially polarized light, but Jones approach does not. In the present paper, we introduce the concept of 4-dimensional Jones type spinor, first for a completely polarized light. This approach is extended to the partially polarized light. From 4-dimensional spinor follow both 4-vector and antisymmetric tensor of Stokes type. Stokes vector depends on four parameters, whereas the Stokes tensor depends on five parameters. By this reason, we can assume that the Stokes tensor contains more information about the partially polarized light than the Stokes vector. We have found relationships between the four components of Stokes vector and five components of Stokes tensor in analytical form, they are studied numerically as well. In addition, we shortly discuss relationships between polarization of the light and space models with spinor structure.

PMMA-based nanocomposites reinforced with metal oxide nanoparticles are the subject of extensive investigation due to their significant potential in nextgeneration transparent electrodes and advanced photocatalytic systems. The central objective is to achieve a finely tuned balance among optical transparency, electrical conductivity, and photocatalytic efficiency – properties that are often mutually limiting in multifunctional materials. To this end, nanocomposite thin films were synthesized via the sol-gel process, incorporating varying concentrations (2%, 5%, and 8%) of metal oxides. ZnO doping was found to effectively preserve high optical transmittance within the visible spectrum. In parallel, the incorporation of Cu₂O led to a marked enhancement in electrical conductivity, achieving up to a 75% reduction in resistivity compared to undoped PMMA, thereby facilitating efficient charge transport. Photocatalytic activity was assessed via the degradation of methylene blue under irradiation, revealing significantly improved performance. Films doped with 8% ZnO exhibited the highest efficiency, with the C_t/C₀ ratio decreasing from 1 to 0.35, indicating substantial pollutant degradation. These findings underscore the promise of PMMA:ZnO and PMMA:Cu₂O nanocomposites as multifunctional materials ideally suited for applications requiring the synergistic integration of optical, electrical, and photocatalytic functionalities.

A theoretical investigation of two-gap superconductivity in iron-based superconductors is presented, using a self-consistent two-band model. This model is necessitated by the presence of two distinct superconducting energy gaps in these materials. The temperature dependence of the superfluid density $(\rho_s)$, London penetration depth $(\lambda_L)$, and lower critical magnetic field $(H_{c1})$ are calculated within this framework. Comparative analysis demonstrates that the two-band model provides a significantly improved description of these properties compared to a single-band BCS model. Furthermore, the individual energy gaps exhibit distinct temperature dependencies, and the contributions to the overall superfluid density from each electronic band are shown to be qualitatively different. The theoretical predictions are found to be in good quantitative agreement with available experimental data, thus validating the two-band model and emphasizing the crucial role of multi-band physics in the superconducting state of iron-pnictides.

Addressing a critical environmental data gap, this study quantifies elemental concentrations (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, Al, Sr, Li, Zn, Ag) in agricultural soils and staple crops (wheat, maize, sunflower) cultivated proximal to the Galati Steelworks, SE Romania. ICP-MS analysis revealed alarming nickel levels in soils, consistently exceeding the alert thresholds, alongside elevated chromium, copper, and zinc. Most crop elements were within typical ranges, showing limited bioaccumulation/exclusion (e.g., Pb, Ag). However, Sr is notably accumulated in plant leaves, as demonstrated by bioaccumulation factors higher than 1. This research provides essential baseline data for robust environmental risk assessment and choosing future pollution mitigation strategies in this industrially impacted agricultural landscape.

Energy and industrial development play a central role in the dynamics of atmospheric emissions. The strong growth in energy consumption and the expansion of industrial activities mainly concern sectors linked to transport, power generation, industrial processes, gaseous emissions, and thermodynamics applied to combustion systems. These emissions dynamics affect several sensitive areas, including atmospheric quality, agriculture, public health, the economy, and urban and natural ecosystems. This study provides an initial overview of emissions in three Moroccan cities: Casablanca, Marrakech, and Essaouira. It also describes the implementation of anthropogenic emissions nationally, including in an urban area with no specific inventory. The results show that the principal emissions sources in these cities are transport and energy consumption. In Casablanca, the variety of the sources is explained by high energy and industrial activity. More data on other cities would be valuable for a better understanding of emissions in Morocco. The modeling section indicates low emission levels, complicating the use of conventional models to simulate air pollution. Human activities generate around 90% of nitrogen and sulfur dioxide emissions. In regions close to the desert, such as Agadir, fine particles (PM₁₀) often come from dust, but anthropogenic emissions remain significant. The low emission levels revealed by the HTAP data underline the importance of using local, regional, or national databases to improve existing inventories and create new ones in other regions, such as Souss-Massa.

While climate variability in Romania since 1961 is well documented, studies spanning on longer periods are few, and use either modelled, or sparse observational data. This paper presents the 100-year trends in precipitation, air temperature (average, minimum and maximum), monthly air temperature range, potential evapotranspiration and water balance over Romania using data from 156 weather stations. The recently released, freely available RoCliHom dataset has been used for this purpose. Trend analysis was conducted with the nonparametric Mann-Kendall test, as it allows a direct comparison with the vast majority of previous studies on climatic changes in Romania. Our results indicate that, since 1924, air temperature had increased over the entire country in all months except autumn, showing that the warming signal has been consistent over the 100-year period. In contrast, annual precipitation amount looks stable at most stations, while 28% show increasing trends. Monthly temperature range had mostly decreased. Potential evapotranspiration has increased in winter, spring and especially in summer, when all stations present upward trends. Water balance had declined in August at almost half of the stations. Generally, the patterns of change are clear, without mixed trends (i.e., trends showing opposite signs for the same variable). Trend magnitudes of annual precipitation and air temperature are strongly correlated (p-value < 0.001) with elevation.

We present examples of specific calculations for determining earthquake parameters and estimating the seismic hazard. First, we examine an earthquake occurred on May 25, 2021, in Vrancea, Romania. We show how to calculate the parameters of this earthquake, and the parameters of the corresponding seismic source. These parameters include the tensor of the seismic moment, the earthquake magnitude and energy, the focal volume, slip, duration and the orientation of the seismic fault. Similar results are given for a Vrancea earthquake of November 3, 2022. Next, we give an example of estimating the seismic hazard, which includes the peak values of soil displacement, velocity and acceleration. These calculations are based on a previously presented theoretical procedure. Also, we give an estimation of the critical dimensions of a building on Earth’s surface, in order to be resistant to an earthquake with given magnitude.

The paper presents a simple yet efficient method for optimizing the spot size formed by a laser beam on a pixelated detector in relation to the detector’s exposure time and the spot detection SNR. The method is applied to the design of the CAS (Constellation Acquisition Sensor) system for the ESA LISA mission, allowing for the identification of the minimal risk design configuration of the CAS optical system. At the same time, the method allows for the identification of the non-compliances of the CAS system design with the ESA design requirements, and hence for the identification of design improvements that would render the CAS system compliant with the said requirements.

Pottery is exposed to many damage factors, including effects of salts, soot, and fats as a result of the soil it is buried in. And because of storing the wax in pottery vessels, or using it to close the pottery vessel. Pottery vessels are also used to preserve food products, such as milk, oils, and other products that appear on the texture of ancient pottery. Therefore, pottery cleaning is one of the first steps in the preservation process, and is the most important and accurate conservation work. Due to the inaccuracy of traditional cleaning, the study aims to evaluate and compare the cleaning with nanomaterial's. Agarose poultices loaded with SDS or Vulpex cleaning agent were prepared in the presence of Nano titanium dioxide. Different analytical techniques, such as the transmission electron microscope (TEM), USB digital optical microscope, scanning electron microscope (SEM-EDX), and measurement of color change have been used to evaluate the cleaning materials and the cleaning process. The results of the microscopic investigation used in the evaluation process revealed that using TiO₂ SDS NPS poultice and TiO₂ Vulpex NPS poultice perfectly removed salt, soot, dust, and wax deposits from the pottery samples' surface. The results of elemental analysis by (SEM-EDX) showed the salts and soot percentage of the treated samples with TiO₂ SDS NPS poultice and TiO₂ Vulpex NPS poultice respectively. The measurement of color change revealed that the treated samples with TiO₂ SDS NPS poultice gave unnoticeable alteration to the human eye.

Outdoor environments expose materials to intense and prolonged ultraviolet (UV) radiation, fluctuating temperatures, moisture, and airborne contaminants. This paper reviews the preparation methods of UV-resistant and transparent coatings and their main strengths and limitations. The advantages and disadvantages of preparation methods are summarized. The final properties of coatings depend on several factors, such as the type of metal nanoparticles, and preparation methods. The potential applications of prepared coatings in various industries, such as solar panels, architectural glass, and automotive industry, are highlighted.