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This article explains development of high strength and lightweight Ti6Al4V5Cr alloy by μ-plasma powder additive manufacturing (μ-PPAM) process for automotive, aerospace, military, dies and moulds, and other similar applications. Microstructure, formation of phases, porosity, microhardness, tensile properties, abrasion resistance, and fracture toughness of multi-layer deposition of Ti6Al4V5Cr alloy are studied and compared with Ti6Al4V alloy. Results reveal that the presence of chromium in Ti6Al4V5Cr alloy refined the grains of its β-Ti and α-Ti phases, increased volume % of β-Ti phase, and promoted formation of its equiaxed grains. It also increased tensile strength, microhardness, abrasion resistance, and fracture toughness of Ti6Al4V5Cr alloy. It enhanced solid solution strengthening and formed higher hardness imparting intermetallic Cr2Ti phase and changed fracture mode to mixed ductile and brittle mode with larger size dimples, cleavage facets, and micropores. But it decreased formation temperature of β-Ti phase and % elongation as compared to Ti6Al4V alloy. Chromium and vanadium content in β-Ti phase of Ti6Al4V5Cr alloy is 7 % and 2.1 % more than its α-Ti phase. This study demonstrates that inclusion of limited amount of chromium content to Ti6Al4V5Cr alloy by μ-PPAM process is very beneficial to enhance microstructure, mechanical properties, crack propagation resistance, and abrasive wear resistance of the Ti6Al4V5Cr alloy. It makes Ti6Al4V5Cr alloy very useful in many commercial applications that require higher strength than Ti6Al4V alloy along with lightweight requirement.

In this paper, we investigate the modified symmetric teleparallel gravity or f(Q) gravity, where Q is the nonmetricity, to study the evolutionary history of the universe by considering the functional form of f(Q)=αQn, where α and n are constants. Here, we consider the parametrization form of the deceleration parameter as q=q0+q1z/(1+z)2 (with the parameters q0(q at z=0), q1, and the redshift, z), which provides the desired property for a sign flip from a decelerating to an accelerating phase. We obtain the solution of the Hubble parameter by examining the mentioned parametric form of q, and then we impose the solution in Friedmann equations. Employing the Bayesian analysis for the Observational Hubble data (OHD), we estimated the constraints on the associated free parameters (H0,q0,q1) with H0 the current Hubble parameter to determine if this model may challenge the ΛCDM (Λ cold dark matter with the cosmological constant, Λ) limitations. Furthermore, the constrained current value of the deceleration parameter q0=−0.832−0.091+0.091 shows that the present universe is accelerating. We also investigate the evolutionary trajectory of the energy density, pressure, and EoS (equation-of-state) parameters to conclude the accelerating behavior of the universe. Finally, we try to demonstrate that the considered parametric form of the deceleration parameter is compatible with f(Q) gravity.

In this article, we attempt to describe the cosmic late-time acceleration of the universe in the framework of f(R,Lm) gravity, by using an effective equation of state, when bulk viscosity is taken into account. We presume a non-linear f(R,Lm) functional form, specifically, f(R,Lm)=R2+Lmα, where α is a free model parameter. We obtain the exact solution of our bulk viscous matter dominated f(R,Lm) model, and then we utilize the combined H(z) + Pantheon + Analysis datasets to estimate the best fit values of the free parameters of our model. Then, we characterize the behavior of the matter–energy density, effective pressure, and the equation of state (EoS) parameter, incorporating the viscous type fluid. The evolution profile of the effective EoS parameter depicts an acceleration phase of the cosmic expansion, whereas the pressure, with the effect of viscosity, exhibits negative behavior, that can lead to the accelerating expansion of the universe. Moreover, the cosmic matter–energy density shows the expected positive behavior. Further, we investigate the behavior of the statefinder parameters for the assumed f(R,Lm) model. We find that the evolutionary trajectory of the given model lies in the quintessence region. In addition, we employ the Om diagnostic test, that indicates that our model exhibits quintessence behavior. Lastly, we check the energy condition criteria and find that the violation of SEC occurs in the past, whereas NEC and DEC satisfy the positivity criteria. We find that our f(R,Lm) cosmological model, with the effect of bulk viscosity, provides a good fit of the recent observational data and can efficiently describe the cosmic expansion scenario.

The standard formulation of General Relativity Theory, in the absence of a cosmological constant, is unable to explain the responsible mechanism for the observed late-time cosmic acceleration. On the other hand, by inserting the cosmological constant in Einstein’s field equations, it is possible to describe the cosmic acceleration, but the cosmological constant suffers from an unprecedented fine-tuning problem. This motivates one to modify Einstein’s spacetime geometry of General Relativity. The f(Q) modified theory of gravity is an alternative theory to General Relativity, where the non-metricity scalar Q is the responsible candidate for gravitational interactions. In the present work, we consider a Friedmann–Lemâitre–Robertson–Walker cosmological model dominated by bulk viscous cosmic fluid in f(Q) gravity with the functional form f(Q)=αQn, where α and n are free parameters of the model. We constrain our model with the Pantheon supernovae dataset of 1048 data points, the Hubble dataset of 31 data points, and the baryon acoustic oscillations dataset consisting of 6 data points. We find that our f(Q) cosmological model efficiently describes the observational data. We present the evolution of our deceleration parameter with redshift, and it properly predicts a transition from decelerated to accelerated phases of the universe’s expansion. Furthermore, we present the evolution of density, bulk viscous pressure, and the effective equation of state parameter with redshift. Those show that bulk viscosity in a cosmic fluid is a valid candidate to acquire the negative pressure to drive the cosmic expansion efficiently. We also examine the behavior of different energy conditions to test the viability of our cosmological f(Q) model. Furthermore, the statefinder diagnostics are also investigated in order to distinguish among different dark energy models.

The crop loss assessment in the present study is based on the premise that yield loss caused by maize stem borer, Chilo partellus (Swinhoe) depends upon the degree of leaf injury measured in the form of leaf injury rating (LIR) that would help in adopting management measures at appropriate time to prevent the loss. The yield of large number of individual plants in two popular maize hybrids, i.e. HQPM1 and DHM117 was recorded at all leaf injury ratings at ICAR-Indian Institute of Maize Research, Pusa Campus, New Delhi. With increasing LIR, the average yield of plants decreased. A set of formula was developed to calculate yield loss, yield loss percentage and monetary loss. A template to calculate the same was formulated in excel sheet by entering input data on LIR scores, average yield at LIR, frequency of plants under each LIR, yield potential of test cultivars and market price of maize grain. The template gives output on yield loss percentage due to C. partellus damage and the corresponding economic loss by entering frequency of plants under each LIR, yield potential of cultivar and the current market price of grain. By comparing economic loss with the management cost, the economic threshold level can be determined which is an essential prerequisite for robust integrated pest management. After the harvest, by deducting actual yield from the expected yield (C. partellus yield loss), the loss caused by other factors is also calculated by the template.

The standard formulation of general relativity fails to describe some recent interests in the universe. It impels us to go beyond the standard formulation of gravity. The f(Q) gravity theory is an interesting modified theory of gravity, where the gravitational interaction is driven by the nonmetricity Q. This study aims to examine the cosmological models with the presence of bulk viscosity effect in the cosmological fluid within the framework of f(Q) gravity. We construct three bulk viscous fluid models, i.e., (i) for the first model, we assuming the Lagrangian f(Q) as linear dependence on Q, (ii) for the second model the Lagrangian f(Q) as a polynomial functional form, and (iii) the Lagrangian f(Q) as a logarithmic dependence on Q. Furthermore, we use 57 points of Hubble data and 1048 Pantheon dataset to constrain the model parameters. Then, we discuss all the energy conditions for each model, which helps us to test the self-consistency of our models. Finally, we present the profiles of the equation of state parameters to test the models’ present status.

The objective of the present paper is to investigate an almost-pseudo-Ricci symmetric FRW spacetime with a constant Ricci scalar in a dynamic cosmological term Λ(t) and equation of state (EoS) ω(t) scenario. Several cosmological parameters are calculated in this setting and thoroughly studied, which shows that the model satisfies the late-time accelerating expansion of the universe. We also examine all of the energy conditions to check our model’s self-stability.

In the present article, we investigate the physical acceptability of the spatially homogeneous and isotropic Friedmann–Lemâitre–Robertson–Walker line element filled with two fluids, with the first being pressureless matter and the second being different types of holographic dark energy. This geometric and material content is considered within the gravitational field equations of the f(T,B) (where T is the torsion scalar and the B is the boundary term) gravity in Hubble’s cut-off. The cosmological parameters, such as the Equation of State (EoS) parameter, during the cosmic evolution, are calculated. The models are stable throughout the universe expansion. The region in which the model is presented is dependent on the real parameter δ of holographic dark energies. For all δ≥4.5, the models vary from ΛCDM era to the quintessence era.

The space-time geometry exterior to a new four-dimensional, spherically symmetric and charged black hole solution that, through a coupling of general relativity with a non-linear electrodynamics, is non-singular everywhere, for small r it behaves as a de Sitter metric, and asymptotically it behaves as the Reissner-Nordström metric, is considered in order to study energy-momentum localization. For the calculation of the energy and momentum distributions, the Einstein, Landau-Lifshitz, Weinberg and Møller energy-momentum complexes were applied. The results obtained show that in all prescriptions the energy depends on the mass M of the black hole, the charge q, two parameters a ∈ Z + and γ ∈ R + , and on the radial coordinate r. The calculations performed in each prescription show that all the momenta vanish. Additionally, some limiting and particular cases for r and q are studied, and a possible connection with strong gravitational lensing and microlensing is attempted.

Sitophilus oryzae is one of the most important stored grain pests of maize causing substantial losses. Owing to high cost, environmental and health hazards, chemical control does not provide an acceptable solution. Host plant resistance offers sustainable and cost-effective way to reduce the losses. A set of 162 diverse inbreds were evaluated to assess their responses to infestation of S. oryzae. Significant variation for (1) grain weight loss (GWL) (4.19–42.32%), (2) emergence of insect progeny (5.67–75.67), (3) germination of infested seeds (GIS) (0.00–81.33%), (4) pericarp thickness (PT) of the grain (47.32–194.83 μm) and (5) grain hardness (GH) (113.00–1,171.67 Newton) was observed among inbreds. GWL and emergence of insect progeny were positively correlated, while GIS was negatively correlated with both. PT and GH did not show any association with other characters. CML442 and CM394 earlier reported to be promising against S. zeamais, were also identified as resistant to S. oryzae. SKV21, Pant109, Pant124, MGB1, CML207 and LM13 were identified as resistant inbreds. These inbreds can potentially serve as valuable donors in the resistance breeding programme. The resistant inbreds can also be crossed with diverse susceptible inbreds to generate mapping populations for identifying QTLs conferring resistance to S. oryzae.

Study of antibiosis is used to identify the sources of resistance in plant germplasm. The quantitative determination of six parameters of antibiosis was carried out in 20 genotypes of maize (Zea mays L.) against Sesamia inferens (Walker). The number of larvae recovered from 30 plants of each genotype at three sampling intervals (7, 14 and 21 days after artificial infestation with neonates) was maximum (39) from WNZPBTL6 and minimum (13) from HKI 1040-11-7 and Basi local. The larval developmental period was found to range from 26-32 days. The expression of antibiosis in terms of prolonged larval period was observed in AEB(Y) C5 55-1 (32 days), PFSR S3 (31 days), CM 202 (31 days), and HKI PC4B (31 days), whereas shortest development period of 26.5 days was recorded in Basi local. Maximum and minimum pupal development period was recorded for AEB(Y)C5 34-7 (10 days) and AEB(Y) C 5-55-1 (7 days) respectively. Strong antibiotic effect of genotype E 30 was observed in terms of the least larval weight (20.53mg). The genotypes Basi local and HKI 164-4-ER-3 did not show much antibiosis as reflected from their maximum larval weight 48.32mg and 46.50mg respectively. The pupal weight ranged from 76.36-120.35 mg in the test genotypes. The leaf feeding symptoms in terms of leaf injury rating (LIR) at 21 days after infestation on a scale of 1 to 9, varied form 4.33-9. Positive correlations were observed between larval weight and LIR (0.52); pupal weight and LIR (0.20); pupal weight and larval recovery (0.27), whereas negative correlation were observed between larval weight and larval period (-0.49); larval weight and larval recovery (-0.46); larval period and pupal weight (- 0.40); and LIR and larval recovery (-0.21). The cumulative susceptibility level of genotypes indicated significant variation among genotypes against Sesamia which can be used to unravel the basis of resistance.

Stored grain weevil (Sitophilus oryzae) has emerged as important storage grain pest of maize, causing substantial economic losses. Owing to high costs and environmental hazards of pesticides, host plant resistance holds promise for effective control of weevils. In the present study, a set of experimental maize hybrids generated using line × tester mating design were evaluated against S. oryzae. Significant variation for grain weight loss (GWL) (6.0–49.1%), number of insect progeny emerged (NIP) (17.8–203.3), grain hardness (GH) (263.1–495.4 N), and pericarp thickness (PT) (60.3–161.0 μm) was observed. Strong positive association was observed between GWL and NIP. GH and PT did not show any correlation with GWL and NIP. Additive and non-additive gene actions were important for both GWL and NIP. Promising inbreds and experimental crosses identified can be effectively utilized in the resistance breeding programme. In majority of promising crosses having desirable SCA effects, one of the parents had desirable GCA effects, indicating that selection of inbred parents based on per se performance for generating resistant crosses may be possible. The commercial hybrid checks were highly susceptible compared to experimental hybrids. The inbreds and experimental hybrids identified hold promise in developing weevil resistant maize cultivars offering sustainable solution to management of weevils in maize.

In this research, friction stir processing (FSP) was carried out on Al0.3CoCrFeNi high-entropy alloys (HEAs) using two different tool geometries (cylindrical and square-shaped pin) at different tool rotational speed (TRS) of 800 and 1000 rpm. Phase analysis exhibited BCC phase in both casted and friction stir processed (FSPed) HEAs. FSP of HEAs with a square-pin tool produced more refined grains in the stir zone than the cylindrical-pin tool. It was also discovered that as the TRS increased, it produced more refined grain size in the stir zone. FSP with a square-pin tool generated a processed zone having highest hardness, ultimate tensile strength, and % elongation due to the evolution of more refined microstructure. Further, a numerical study was performed using ABAQUS/Explicit finite element software to understand the complex thermo-mechanical process and to study the stress distribution, temperature distribution, and material flow behaviour during FSP. The numerical study involved the Johnson-Cook models for defining material flow behaviour during FSP. A coupled Lagrangian-Eulerian technique was used to control mesh distortion while simulating excessive deformation. The peak temperature of the FSPed zone got enhanced as the TRS increased, and the temperature enhancement was higher with a square-pin tool than a cylindrical-pin due to pulsating motion. [ABSTRACT FROM AUTHOR]

In this study, the geometrically deformed compact objects in the f(Q, T) gravity theory under an electric field through gravitational decoupling via minimal geometric deformation (MGD) technique are developed for the first time. The decoupled field equations are solved via two different mimic approaches Θ00=ρ${\Theta}_{0}^{0}=\rho $ and Θ11=pr${\Theta}_{1}^{1}={p}_{r}$ through the Karmarkar condition. Physical viability tests are conducted on our models and examine how decoupling parameters affect the physical qualities of objects. The obtained models are compared with the observational constraints for neutron stars PSR J1810+174, PSR J1959+2048, and PSR J2215+5135, including GW190814. Particularly, by modifying parameters α and n, the occurrence of a "mass gap" component is accomplished. The resulting models exhibit stable, well‐behaved mass profiles, regular behavior and no gravitational collapse, as verified by the Buchdahl–Andréasson's limit. Furthermore, a thorough physical analysis that is based on two parameters: n (f(Q, T)–coupling parameter) and α (decoupling parameter) is provided. This work extends our current understanding of compact star configurations and sheds light on the behavior of compact objects in the f(Q, T) gravity. [ABSTRACT FROM AUTHOR]

The significant properties and phase transition of charged Anti‐de Sitter (AdS) black holes have been extensively studied in a variety of modified theories of gravity in the presence of numerous matter fields. The goal of the current research is to investigate the AdS black hole's thermodynamics under the impact of f(Q)$f(Q)$ gravity. Additionally, this paper explores the black hole's local stability and phase structure under the relevant gravity. Besides, Ruppeiner geometry is used to look into the AdS black hole's microscopic structure. The Ricci curvature scalar R to explain the interactions between the AdS black hole's microscopic particles under the influence of f(Q)$f(Q)$ gravity have been numerically computed. [ABSTRACT FROM AUTHOR]