Iranian Journal of Science and Technology, Transactions A: Science最新文献

First, we establish some extended and refined results in the theory of viscosity solutions including a continuous dependence theorem, and a regularity result. Then, by investigating a certain type of partial differential equations, we expand the application of viscosity solutions to a broad range of higher-order partial differential equations. Finally, in the last section, we prove some corollaries that show the applicability of our results.

The Rudimentary Analysis of Edible Silver foil has been Investigated by a Magnetic Field (B)-supported LIBS. The Silver Plasma was Produced by Employing an Nd-YAG Pulsed Laser (100 mJ,1064 nm,) on the Surface of Silver foil in the Presence of B = 0.75 T, which Analyzed the Significant Enhancement in the LIBS Sensitivity by Detecting the Essential and Toxic Elements (C, Ag, Al, Fe, Ca, Cr, Si, Mg, Na) in Silver Plasma. The Enhancement Factor is up to four-fold and Optical Emission Intensity, Plasma Parameters like Plasma Temperature (T_e) and electron Number Density (n_e) were Enhanced in the Presence of a Magnetic Field (B). The Signal Enhancement in Silver Plasma was Ascribed to Magnetic Confinement and an Increase in Recombination rate after Relaxing the Plasma. Moreover, the Value of Thermal beta is Estimated Analytically (βt < 1) in this Study, which Confirms the Validity of Magnetic Confinement in all Samples. The Elemental Composition was Determined by the Calibration-Free LIBS (CF-LIBS) Approach with Zero Fields and B-field. The Result Revealed that Silver Foils were Fraudulently Adulterated by 25–35% Aluminum, and 0.8–1.08% Chromium, which Eventually Accumulates in the Human body via the food Chain Leading to high Risks to Human Health

In this study, we examined the potential ability of the sulfonated melamine–formaldehyde resin (SMFR) as an acidic heterogeneous catalyst in the multicomponent synthesis of 3, 4-dihydropyrimidine. The incorporation of sulfonic acid groups into the melamine–formaldehyde resin framework resulted in a highly active and recyclable catalyst, promoting reactions under mild and environmentally friendly conditions. Key advantages of this method include short reaction times, high product yields, and efficient catalysis with minimal catalyst loading. The synthesized compounds were structurally confirmed through FT-IR, ¹³C NMR, and ¹H NMR spectroscopy, demonstrating the efficiency and reliability of the catalytic system under green synthesis conditions.

Graphical Abstract

Let (V_3(z,f)= (3/4)z+(3/10)a_2z^2+(1/20)a_3z^3) and (sigma _3^{(alpha )}(z,f)=z+(2/(2+alpha ))a_2z^2+(2/[(2+alpha )(1+alpha )])a_3z^3) be the cubic polynomials representing, respectively, the 3rd de la Vall(acute{e})e Poussin mean and the 3rd Ces(grave{a})ro mean of order (alpha ; (alpha ge 0)) of a normalized analytic function (f(z) = z+sum _{k=2}^{infty } a_k z^k.) If (mathscr {K}) denotes the usual class of normalized convex univalent functions in the open unit disc ({mathbb {D}}) in the complex plane centered at the origin, we demonstrate that (V_3(z,f)prec sigma _3^{(alpha )}(z,f)) in (mathbb {D}) for all (fin mathscr {K}) and for all real numbers (alpha) satisfying (3le alpha le 19). For all (alpha ge 19,) we also identify a sharp real number (multiplier) (gamma (alpha )) such that (gamma (alpha )cdot V_3(z,f)prec sigma _3^{(alpha )}(z,f)) in (mathbb {D}) for all (fin mathscr {K}.) Here ‘(prec)’ denotes subordination between two analytic functions.

This article proposes a new formulation of the adaptive finite element and finite difference methods to obtain an approximate solution to the Riesz-Caputo space-time fractional partial differential equations. We propose the targeted algorithm for complexity addressing in one dimensional nonuniform meshes. The proposed technique uses a known gradient recovery method with optimal accuracy: the polynomial preserving recovery technique, and offers adaptivity. This procedure is based on extensive analytical results about error margins, stability criteria, etc. To emphasize its efficiency even more, the article gives numerous numerical examples showing the algorithm has advantages over the other numerical approaches. This shows the method’s efficiency and a useful implementation for these kinds of fractional partial differential equations posed in fractional calculus.

The purpose of this present article is to illustrate the approximation and related properties of Szász-Jakimovski-Leviatan type operators constructed using Beta functions. In this context, approximations are obtained by constructing a new class of Szász-Jakimovski-Leviatan Beta type operators, which are introduced through the Appell polynomials in Dunkl formulations. In the investigations, the approximation is studied in Korovkin’s and weighted Korovkin’s spaces involving local and global approximations. The rate of convergence is also obtained in terms of the weighted modulus of continuity, Lipschitz functions, Peetre’s K-functional, and some direct theorems. Consequently, in the final paragraph, approximations are studied through A-statistical convergence.

Human papillomavirus (HPV) is a sexually transmitted infection that affects the cervix (the lower part of the uterus leading to the vagina) and is often associated with cervical cancer. This paper introduces a control-induced deterministic model to analyze and combat the spread of HPV and cervical cancer in India. We establish the nonnegativity and boundedness of the solution of the model and also provide the basic reproduction number (mathcal {R}_0). The existence of equilibria in the model is determined. An objective functional is formulated to reduce HPV and cervical cancer infections by raising awareness among the susceptible population through educational campaigns. The existence of the optimal control is proved, and the necessary conditions for the optimality system are derived. Utilizing Pontryagin’s maximum principle, we explicitly formulate the optimal control. Through numerical simulations, we elucidate the pivotal role of the control variable: that is, its absence leads to (mathcal {R}_0 > 1), indicative of sustained disease transmission, while its inclusion reduces (mathcal {R}_0 < 1), signaling a decline in outbreaks. Notably, varied control variable values exert substantial influence on the model dynamics. The stability of equilibria is established graphically. Moreover, the obtained findings underscore the efficacy of educational campaigns in mitigating HPV spread, offering promising avenues for disease control and prevention.

Deformative forces exert stress on rock formations, when sufficient, these forces turn penetrative, correspondingly causing the rocks to accommodate strain. Numerous strain measurement techniques (Finite strain analysis) have been documented by early pioneers in kinematics, among which R_f/ϕ method is utilized in the current investigation of the southern region of the Proterozoic Kaladgi basin near Bagalkot. The Kaladgis show significant structural disturbance (joints, faults, and shears), making them suitable for Kinematic Study. This study focuses on measurement of the strain across the doubly plunging fold, which includes both anticline and syncline in a fold system. Oriented samples were used for thin sections. Meticulously procured Optical photomicrographs of these samples were analysed using the R_f/ϕ approach in Ellipse Fit V3.11.0 software with designated tools and methods. The samples exhibit a strain range of R_s 1.16 to 1.99 for XZ sections and, ε_s (Strain amount) 0.099 to 0.427 which accounts the amount of force acting on a plane at an angle. In Flinn and Logarithmic diagrams to visualise data, all samples fall within the apparent flattening field, indicating compressional forces exerted on a spherical body resulted in a flattened oblate ellipsoid geometry (σ1 = σ2>>σ3) indicative of compressional tectonic and progressive deformation. These are defined by the Flinn parameter (k) and d value, a potential measure of strain intensity, (0.1189 to 0.6242) whose variation proves strain localisation defined by higher ellipticity of grains.

Since the prediction of the Quark Gluon Plasma, a new phase of matter, more than a decade ago, significant amounts of research has been dedicated to the study of relativistic nucleus-nucleus and hadrons-nucleus collisions. In this article we have focused our study on the emission feature of shower, grey and black particles emerged from the interactivity of (^{84}Kr) with different target nuclei of emulsion. We have studied average multiplicity of shower, grey and black particles as well as their dependence on mass of projectile and target nuclei. The results of the experiments indicate that the average multiplicity of black particles is roughly constant, while the average multiplicity of shower and grey particles rises with projectile mass ((A_{p})). The results were also compared with calculated values obtained from multisource thermal model and found to be consistent. We have also studied the normalized multiplicity distribution of shower, grey and black particles. The data were also compared with other available experimental observations and the calculated values obtained from the multisource thermal model. The observation shows that the emission feature of shower, grey and black particles were well explained by multisource thermal model.

The adsorption of the phosgene oxime (CX) molecule from different orientations on the pure (111) TiO₂ surface was studied using periodic DFT calculations. Adsorption energies are negative in all configurations, indicating the formation of stable adsorption systems. However, further analysis focused on the adsorption of the CX via its N atom on the surface, which exhibited the highest adsorption energy. Furthermore, the total density of states and HOMO–LUMO calculations were performed to investigate the effect of the CX adsorption on the electronic properties of the pure and doped (111) TiO₂ surfaces. It should be noted that the (Zr⁺⁴–S⁻²) and Ge⁺⁴ doped (111) TiO₂ surfaces have the highest and lowest adsorption energy with the values of − 85.92 and − 19.39 kcal/mol, respectively, compared to the other doped adsorption systems. Nevertheless, the (Ge⁺⁴) adsorption system exhibits the largest variation in band gap energy (2.20 and 2.73 eV for the Ge- adsorption system and Ge-surface, respectively ∼20% change) during CX adsorption, indicating the highest change in its electrical conductivity. Consequently, the Ge⁺⁴-doped adsorption system is a promising sensor of toxic CX molecule.