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In this paper, we discuss the existence and uniqueness of isolated periodic traveling wave solutions of a family of nonlinear reaction–convection–diffusion equations using the monotonicity of the ratio of Abelian integrals. A numerical study is also presented. [ABSTRACT FROM AUTHOR]

The purpose of this research was to develop glasses that are thermally reflective, radiation-resistant, and mechanically robust. We have synthesized the La(20-x)Pb10B70:Eux series of glasses in this regard. Then, characterization, radiation shielding, structural analysis (Raman, FT-IR, DTA, SEM, XRD, and EDX), dielectrics, thermoluminescence are planned. The XRD and SEM analyses of the test samples reveal a vitreous appearance. The chemical constituents are identified by the EDX analysis in terms of their percentage of atomic weight. The density (2.592 g/cm3) and molar volume (45.44 cm3 mol−1) of the fabricated glass were evaluated as physical properties. The glass transition temperature (approximately 273 °C) and thermal stabilities (0.656 percent) of glasses are determined to be solely dependent on Eu3+ ions, according to DTA investigations. FT-IR and Raman analyses were employed to determine the various structural vibrations of the sample glass. By employing the ultrasonic velocities of the test glasses, an assessment was conducted on the micro-hardness of the glass (5.01 GPa). The shielding characteristics of radiation, such as RPE (31.6 percent) and MAC (16.9 cm2/g), indicate that the shielding behavior is solely the result of the Eu3+ ions. It has been observed that TL properties are examined at gamma irradiation intensities ranging from 5 to 25 kGy. An evaluation was conducted on the frequency factor (3.225 × 1021 S−1) and A.E. (1.785 eV) of glasses. The findings indicate that the TL characteristics of glasses are solely influenced by the Eu3+ ions. Additionally, the investigation of the dielectric properties of glasses was ascertained. The analysis focused on the dielectric constant (8.891), dielectric loss (0.026), ac conductivity (0.735 × 10–8 Ω−1 cm−1), and A.E. (1.051 eV) values of the fabricated glass. The findings suggest that the dielectric properties of glasses are entirely determined by the presence of Eu3+ ions. Overall the LBPE-1.5 glass found to be best in the structural, mechanical, optical, dielectric, radiation shielding and thermoluminescence properties. [ABSTRACT FROM AUTHOR]

This paper explores wind energy control systems, with a special emphasis on the implementation of Enhanced Direct Torque Control (DTC) in wind turbines that use Doubly Fed Induction Machines (DFIM). The main goals are to improve the turbines' ability to withstand voltage fluctuations in the power grid and remove the need for crowbar protection by including an LCL filter. The study highlights the crucial importance of Enhanced DTC in ensuring the steady functioning of turbines under demanding grid circumstances, including as voltage swings. The use of an LCL filter is crucial in reducing high-frequency elements, thereby minimizing the effects of voltage dips. Furthermore, the research emphasizes the enhanced control structure produced via the removal of crowbar protection, eventually enhancing the dependability of the system. Finally, the proposed work enhances the optimization of wind turbines that use DFIM technology by using sophisticated control algorithms. This adds to improving the efficiency and sustainability of wind energy production. [ABSTRACT FROM AUTHOR]

Soil microbial communities are important drivers of biogeochemical cycling of nutrients, organic matter decomposition, soil organic carbon, and Greenhouse gas emissions (GHGs: CO2, N2O, and CH4) and are influenced by crop and soil management practices. The knowledge on the impact of conservation agriculture (CA) on soil bacterial diversity, nutrient availability, and GHG emissions in semiarid regions under rainfed conditions is vital to develop sustainable agricultural practices, but such information has not been systemically documented. Hence, studies were conducted for 10 years in rainfed pigeonpea (Cajanus cajan L.)-- castor bean (Ricinus communis L.) cropping system under semi-arid conditions to assess the effects of tillage and crop residue levels on the soil bacterial diversity, enzyme activity (Dehydrogenase, urease, acid phosphatase, and alkaline phosphatase), GHG emissions, and soil available nutrients (Nitrogen, phosphorus, and potassium). Sequencing of soil DNA through Illumina HiSeqbased 16S rRNA amplicon sequencing technology has revealed that bacterial community responded to both tillage and residue levels. The relative abundance of Actinobacteria in terms of Operational Taxonomic Unit (OTUs) at phyla, class as well as genera level was higher in CA (NTR1: No Tillage + 10 cm anchored residue and NTR2 NT + 30 cm anchored residue) over CT (conventional tillage without crop residues). CA resulted in higher enzyme activities (dehydrogenase, urease, acid phosphatase, and alkaline phosphatase) and reduction in GHG emissions over CT. CA recorded 34% higher and 3% lower OC, as compared to CT, and CTR1, respectively. CA recorded 10, 34, and 26% higher available nitrogen, phosphorus, and potassium over CT and CTR1, respectively. NTR1 recorded 25 and 38% lower N2O emissions as compared to CTR1 and CTR2, respectively. Whereas only NT recorded 12% higher N2O emissions as compared to CT. Overall, the results of the study indicate that CA improves the relative abundance of soil bacterial communities, nutrient availability, and enzyme activities, and may help to contribute to the mitigation of climate change, and sustainability in rainfed areas. [ABSTRACT FROM AUTHOR]

In this paper, we define enriched (ψ, φλ)-weakly contractive map in convex metric spaces where ψ is continuous on [0,+∞) and φλ is not continuous on [0,+∞) and prove the existence and uniqueness of fixed points of these maps in complete convex metric spaces. We provide an example in support of our result. [ABSTRACT FROM AUTHOR]

In this article, we investigate an initial-boundary value problem posed for generalized Burgers equation (GBE) with linear damping via the method of matched asymptotic expansions. Asymptotic solutions are constructed for different sub-regions of the domain |$x > 0,~ t > 0$|⁠. A special solution is derived, and it describes the large-time asymptotic behavior of the solutions of the GBE for certain parametric ranges. We also observe that a stationary solution of the GBE describes the large-time behavior of solutions for certain parametric ranges. The existence and uniqueness of the relevant stationary solution are proved using a shooting argument. A numerical study is presented comparing the numerical solutions (obtained by the method of lines) with the asymptotic solutions constructed. [ABSTRACT FROM AUTHOR]

Maraging steels are ultra-high strength iron nickel-based alloys which are used in military applications like rocket motor casings, missiles, and ship hulls. In the current work, maraging steels of 250 grade butt joints with 2 mm thickness are welded by using Nd:YAG laser. The experiments were designed and conducted using the L16 orthogonal array. Various welding parameters selected for the current work are laser power, welding speed, and focal position, whereas tensile strength, hardness and depth of penetration were considered as the output responses. The influence of process variables on weld bead morphology was analysed experimentally. The microstructure, mechanical characteristics and numerical analysis of the optimum joint were also investigated. Analysis of variance (ANOVA) was used to determine the effect of different variables on tensile strength and depth of penetration. According to the results, laser power and welding speed are essential factors for tensile strength. The depth of penetration is strongly influenced by welding speed, focal position, and laser power. In order to predict the weld bead, finite element analysis was performed on ABAQUS 3D finite element software. The results reveal that finite element simulation and experimental observations are matched. [ABSTRACT FROM AUTHOR]

Rapid population increase, urbanization, soil degradation and inappropriate management practices have put tremendous pressure on natural resources, particularly on soil, water, and vegetation. Soil resource is vital for farming to provide food and nutritional security performing ecosystem functions and services and achieving Sustainable Developmental Goals (SDGs). Worldwide, ~33% soil resource has been adversely degraded by diverse processes. To protect soil resource from further degradation, there is a strong need of sustainable soil management practices for enhancing soil organic carbon (SOC), soil health, and crop production in a sustainable manner. "No-till farming (NT)/conservation agriculture (CA)" has been widely practiced worldwide on about 210 million ha. The long-term NT experiments play a significant role in improving soil health, SOC sequestration, and in-depth understanding of greenhouse gas (GHG) emission, climate change mitigation and optimizing resource use efficiency, to cater for the needs of the present- and future-generations. According to FAO, NT/CA is a farming system that promotes minimum soil disturbance (i.e., no tillage), maintenance of a permanent soil cover, and diversification of plant species. This system increases biodiversity and natural biological processes in above- and below-ground surface, which helps in enhanced water- and nutrient use-efficiency and sustained crop production. From the literature, it is evident that shift from traditional/conventional tillage (CT) with residue burning/removal to NT/CA farming has been recognized as an important soil management practice/strategy for sustaining soil health, reducing soil erosion and reversing soil degradation. This chapter deliberates the effect of NT/CA on soil health, nutrient stratification, SOC dynamics through modeling, SOC sequestration, GHG emissions, socio-economic condition in adoption and also suggesting the future perspectives on NT and CA. [ABSTRACT FROM AUTHOR]

ZnO-CaF 2 -P 2 O 5 glasses doped with different concentrations of V 2 O 5 (ranging from 0 to 1.0 mol %) were prepared. The prepared bio glasses are soaked in SBF for duration of 2, 3, 7 and 10 days in separate plastic containers and then kept in incubator maintained at body temperature 36.5 °C. The influence of valence states of vanadium ions (V 4+ /V 5+ ) with respect to the structural aspects by means of FTIR and Raman Spectra, elastic properties by means of relevant parameters, the thermal stability by means of DTA studies and other spectroscopic properties by using OA and ESR studies are studied. The raise in wavenumber and comparative areas of the two absorption bands corresponding to electronic transitions 2B 2g → E 2g , 2B 2g → 2B 1g respectively in optical absorption spectra of these CZPV glasses clearly indicate that vanadium ions have octahedral co-ordination with tetragonal compression due to modifier action of V 2 O 5 in the glass network. The optical absorption and ESR studies have revealed that vanadium ions exist in V 4+ states. The characteristic temperatures of these prepared glasses obtained from DTA curves explain modifications taking place in the structure of glass network. The structural changes are explained with the aid of FTIR and Raman studies. The bio active nature of the titled glasses is evident from dissociation and pH studies by SEM &EDS of these glasses before and after immersion into SBF., (Copyright © 2022 Elsevier Ltd. All rights reserved.)