This study explores the fabrication of hematite (α-Fe2O3) nanoparticles utilizing aqueous extracts of Plectranthus amboinicus, which act as reducing and stabilizing agents. The prepared hematite (α-Fe2O3) nanoparticles have been characterized by TGA, PXRD, FT-IR, Raman, DRS UV–visible, Photoluminescence, SEM, Particle size distribution, and zeta potential measurements (DLS), respectively. According

The aim of this paper is to show that a supercritical Neumann problem has at least one positive radial solution via recent variational principle and defining an energy functional with a hidden symmetry associated with the problem. Also, we study the problem in the setting of the Heisenberg group \({\mathbb {H}}^n\), which is a special case of locally compact groups.

The LSQR iterative method is a Krylov subspace method for solving least-squares problems. Early termination is rare, and it is common for LSQR to require many iterations before an approximation of the solution with desired accuracy has been determined. In this paper, we present a restarted LSQR method and we use a new technique for accelerating the convergence of restated by adding some approximate

Habitat-associated morphological divergence of the three-spined stickleback, Gasterosteus aculeatus populations was investigated in the southern Caspian Sea basin using landmark-based geometric morphometric method to understand the population structure of this invasive species. A total of 127 specimens were collected from three stations, including the Babol River estuary (center), Gomishan Wetland

Providing strategies for coping and managing NaCl salinity stress is the goal of many researches. Titanium dioxide nanoparticles (TiO2 NPs) are widely used as photo-catalytic agents due to their strong oxidative properties, optical stability, lack of toxicity, cheapness and availability. Here, the effects of various concentrations of NaCl salinity and titanium dioxide nanoparticles on certain growth

Microwave dielectric ceramics in the Ca1-xSrxTiO3 (0 ≤ x ≤ 0.7) composition series were fabricated via conventional solid state, mixed oxides route. The structural, microstructural and microwave dielectric properties of the sintered samples were investigated. The XRD patterns revealed the formation of a single-phase perovskite-structured compositions calcined at 1000 °C for 3 h in air. The structure

Background Researches implement microcantilevers (MCs) as a biosensing technique lately. Various researches develop such platforms experimentally. Herein, simulation is the method of the choice to predict accurate response of the biosensor during design. Objective The current study aims to provide a prediction method that enables adequate response order. Such results enable the enhanced design of the

In the present paper, we describe cubic spline combined with high accuracy compact formulation for computing approximate solution values to nonlinear convection-dominated diffusion equations, and apply the method to several variants of Burger’s type parabolic partial differential equations. A combination of cubic spline interpolating polynomial and quasi-variable grids sequence yields a two-level implicit

Utilizing the concepts of subordination we have introduced a generalized class Salagean-Type of complex-valued multivalent harmonic functions. We construct some properties of our class. The results obtained here include a number of known and new results as their special cases.

In this paper, we propose a numerical technique based on the method of fundamental solutions (MFS) for solving a classical optimal shape design problem. The problem contains a free boundary condition which should be approximated to find the optimal domain for the solution of Laplace equation. For solving the considered optimization problem, we introduce a meshless regularization technique based on

Imidazolium-based ionic liquids 1-hexyl-3-methylimidazolium hexaflorophosphate, and 1-hexyl-3-methylimidazolium tetrafloroborate were used to determine pH dependent-ionic forms of Valine and Aspartic acid in aqueous solutions. For this purpose, the partitioning behaviors of both compounds between the aqueous phase with different pH values and ionic liquid phase were investigated. The results revealed

In Southern and Southern East Asia, the eggplant fruit and shoot borer (BSFB) is the most harmful pest for eggplant. The pest is known to cause about 16 and 70% damage to shoots and fruits, respectively. It is of practical importance to precisely trace the genetic variability in the expanding geographical distribution of the pest. In the current study, the genetic variability was analysed among geographically

This article deals with a class of non-smooth mathematical programming with vanishing constraints. We introduce several kinds of constraint qualifications for these problems, and we study the relations between them. Then, we apply these constraint qualifications to obtain several stationary conditions. Finally, a sufficient condition for optimality of the problem is presented.

By employing the classic hydrodynamic model of semiconductor-plasmas, an analytical investigation is made to study the piezoelectric contributions to optical parametric amplification of acoustical phonons in magnetized doped III–V semiconductors. Assuming the origin of nonlinear interaction to lie in nonlinear-induced current density and electrostrictive polarization of the medium, expressions are

This study investigated the impact of the dietary supplementation of the water extract of algae Iyengaria stellata (IE) on the growth performance, fatty acid composition, antioxidant activity and disease resistance of shrimp Litopenaeus vannamei against Photobacterium damselae. A total number of 600 post larvae shrimp L. vannamei (mean 0.86 ± 0.01 g) were randomly divided into four groups (at three

Diabetes mellitus is associated with increased oxidative stresses, kidney damage, ocular neuropathy, and atherosclerosis. In the present study, the protective effect of Rubus fruticosus hydroethanolic extract on the biochemical parameters in streptozotocin (STZ)-induced diabetic rats were investigated. In this experimental study, 40 male Wistar rats were divided into five groups (n = 8) as control

Månsson and Shukur (Econ Model 28:1475–1481, 2011) proposed a Poisson ridge regression estimator (PRRE) to reduce the negative effects of multicollinearity. However, a weakness of the PRRE is its relatively large bias. Therefore, as a remedy, Türkan and Özel (J Appl Stat 43:1892–1905, 2016) examined the performance of almost unbiased ridge estimators for the Poisson regression model. These estimators

In this paper, we consider diffusive micropolar equations in porous media and present linear stability regimes of parameters. We find all parametric eigenvalues and eigenvectors of the linear part of the Brinkman–Eringen equations. Then, we show that this linear part of the operator is sectorial. We also find two critical parameters that dictated Hopf and saddle-node bifurcations of the problem. Finally

Biofilms on the tooth surface that are not removed regularly can lead to dental caries, gingivitis, or periodontal disease. Recently, numerous newly developed sterilization approaches and techniques based on nonthermal temperature gas plasma have been introduced in the medical field. This study investigates the influence of nitrogen-based nonthermal atmospheric pressure plasma jet (NTAPPJ) treatment

In the present investigation, significant physical parameters such as incubation time, temperature and pH were optimized for cellulase production by wild and mutant strains of thermophilic Thermomyces dupontii. For a comparative analysis, three independent variables which were selected from OVAT were subjected to RSM. As per response surface methodology (RSM) model, central composite design was used

We derive some classical and fractional properties of \(_pR_q(\lambda ,\eta ;z)\) function using fractional calculus approach involving Hilfer fractional derivative operator. Further, we introduce an integral operator which contains \(_pR_q(\lambda ,\eta ;z)\) function as a kernel: \(\begin{aligned} \left( {\mathcal{R}}_{\lambda ,\eta ,\mathbf{u}_{\mathbf{p}},\mathbf{v}_{\mathbf{q}},\omega ;a+} f\right)

In this paper, approximate duals and Q-approximate duals of standard Bessel sequences are studied, where Q is a bounded (not necessarily adjointable) operator on a Hilbert \(C^*\)-module. Particularly, we consider the stability of Q-approximate duals under morphisms of Hilbert \(C^*\)-modules and also their stability under small perturbations is discussed. Then, we get some properties of (a, m)-approximate

The jujube is very important in Iran’s horticultural sector, and its value-added is very high for per cubic meter of water consumed. The chromosome number and genetic diversity of 25 jujube trees from different regions of South Khorasan Province were assessed using 24 simple sequence repeat (SSR) and 16 random amplified polymorphic DNA (RAPD) markers. The polymorphism percentage was 100% and 67.59%

This paper introduces a new hybrid fractional model for image denoising. This proposed model is a combination of two models Rudin–Osher–Fatemi and fractional-order total variation. We try to use the advantages of two mentioned models. In this regard, after introducing an appropriate norm space, we prove the existence and uniqueness of the presented model. Furthermore, finite difference method is employed

So far, although there have been several articles on partial differential equations with piecewise constant arguments, as far as we know, there is no article on neither a heat equation with piecewise constant mixed arguments that includes three extra diffusion terms, delayed arguments \([t-1], [t]\) and an advanced argument \([t+1],\) or exploring qualitative properties of the equation. With the motivation

In this research, the influence of the biasing voltage on hydrogen temperature and plasma confinement is investigated in the IR-T1 tokamak. The applied voltage was in the range of − 250 to + 250 V. Hydrogen (Hβ) temperature was estimated using measurements provided by the optical system based on a two-channel AvaSpec-ULS3648TEC-2-RS-USB2 visible light spectrometer on IR-T1 tokamak. The FWHM of Hβ spectral

The thermal performance of longitudinal radiative–convective fins with rectangular, trapezoidal, and concave parabolic profiles was analyzed by the homotopy perturbation method (HPM). The governing equation of the problem was obtained by establishing the energy balance for a longitudinal element on the longitudinal radiative–convective fin. In addition, thermal conductivity, convective heat transfer

In this research, the negative beta decay energy (\(Q_{\beta }^{ - }\)) is expressed in terms of the nuclear binding energies instead of the mass values of a wide spectrum of nuclei that extend between 2 ≤ Z ≤ 97. The quark-like model (QLM), which can efficiently identify nuclear binding energies, has been used to obtain a new formula to express a negative beta decay energy (\(Q_{\beta }^{ - }\)),

One of the fundamental problems in the field of image processing is denoising. The underlying goal of image denoising is to effectively suppress noise while keeping intact the significant features of the image, such as texture and edge information. The gradient of image is a famous feature descriptor in denoising models to distinguish edges and ramps. If the received signal of an image is very noisy

The inverse problem of reconstructing the timewise term along with the temperature in the nonlocal diffusion equation with initial and boundary conditions and additional measurement (an integral and partial heat flux) is, for the first time, numerically investigated. This inverse problem appears extensively in the modeling of various phenomena in engineering and physics. The inverse problem considered

The great ecological tolerance of aphaniid tooth-carps (Aphaniidae) suggests that the genetic-based adaptation to divergent osmoregulatory environments may be an important driver of the aphaniid fish diversity. This study was conducted to assess gill mRNA expression levels of two osmoregulatory genes, i.e., the CLC-3 and the Na+/K+-ATPase in two tooth-carps inhabiting the freshwater (FW) spring and

In this work, we find a system of generators for the Picard modular group \(SU(2,1,{\mathcal {O}}_{11})\). This system contains four transformations, two translations a rotation and an involution.

A fisheye-based optical head which contains eight lens elements was designed and developed for an imaging laser detection system. The field of view is more than 180 degrees in visible and near-infrared (NIR) wavelength. The F/# of the system is less than 3 and the effective focal length is about 2.4 mm which are critical for imaging laser detection systems in the NIR spectrum. The MTF characteristic

Electrochemical removal of synthesis solution containing 50 mg/L auramine-O through Ti/PbO2 electrodes and carbon felt air-diffusion electrode to in situ generate hydrogen peroxide (H2O2) by the oxygen (O2) reduction. The effects of operating conditions, FeSO4·7H2O concentrations, current density, initial concentration, initial pH value and sodium sulfate (Na2SO4) concentration were investigated. For

According to mathematical literature, the parametric spline functions have not been used directly for solving the integral equations so far. In this work, we develop the tension spline approximation to obtain the numerical solution of Volterra–Fredholm integral equation. First, the tension spline method was obtained and then the combination of this method with the quasi-linearization method has been

The Hopf algebraic structure problem for a two-parameter deformed white noise Heizenberg algebra based on the two-parameter deformation of canonical commutation relations is discussed. Firstly, in the basis of the (p, q)-Fock space, we present the Fock realization of the (p, q)-deformed quantum Heizenberg algebra, and we give its Hopf structure.

Eocene vertebrate footprints from the uppermost layers of the Karaj Formation have been discovered in the Taleghan valley, Alborz Mountains, northern Iran. Trackways comprise carnivore and artiodactyl footprints. Footprints of primitive and small artiodactyl are assigned to Gambapes hastatus, with 16–18 mm footprint length. Carnivore trackways belong to the Felidae or Mesonychidae, recognized as Pycnodactylopus

Given a densely defined closed operator \(T:{\mathcal {D}}(T)\subset H\rightarrow K\), von Neumann defined \(W:=(I+T^*T)^{-1}\) and showed that \(0\le W\le I\), \({\mathcal {K}}(W)=\{0\}\) and \(T^*T=(I-W)W^{-1}=W^{-1}(I-W)\) with \({\mathcal {D}}(T^*T)={\mathcal {R}}(W)\). (Here, \({\mathcal {D}}(\cdot )\), \({\mathcal {R}}(\cdot )\), \({\mathcal {K}}(\cdot )\) and, later, \({\mathcal {G}}(T)\) stand

In this work firstly real semi-quaternion matrices and their properties are examined. Then, \(2n\times 2n\) complex adjoint matrix and \(4n\times 4n\) real matrix representation of a real semi-quaternion matrix are expressed. Further systems of linear real semi-quaternionic equations are investigated and in some of them the \(2n\times 2n\) complex adjoint matrix and the \(4n\times 4n\) real matrix

This paper addresses a computationally efficient robust tube-based model predictive control (RTBMPC) strategy of linear systems in the presence of bounded disturbance. In the RTBMPC strategy, a nominal system is introduced by ignoring the disturbances of uncertain system, and then the uncertain system will be controlled in a robust manner through its nominal system as well as an additional feedback

Let \(\alpha =\alpha (G)\) be the independence number of a simple graph G with n vertices and I(G) be its edge ideal in \(S=K[x_1,\ldots , x_n]\). If S/I(G) is Gorenstein, the graph G is called Gorenstein over K, and if G is Gorenstein over every field, then we simply say that G is Gorenstein. In this article, first we state a condition equivalent to G being Gorenstein, and using this, we give a characterization

In the present study, Caputo derivative-based a new fractional-order epidemic model is presented along with two explicit saturated incidences and saturated treatment rates. For this, a new fearful population compartment is incorporated into the susceptible-infected-recovered compartmental model, which emphasizes to consider two specific incidence rates: one from susceptible individuals’ compartment

In this paper, we introduce a new family of generalized blending-type bivariate Bernstein operators which depends on four parameters \(s_{1}\), \(s_{2}\), \(\alpha _{1}\) and \(\alpha _{2}\). Approximation properties of these operators are studied, and we obtain the rate of convergence in terms of mixed and partial modulus of continuities. Moreover, we prove a Korovkin- and a Voronovskaja-type theorems

Habitat suitability models can be generated using methods requiring information on presence of species or presence and absence of species. Rhinopoma muscatellum is one of the six mouse-tailed bats (Rhinopomatidae) and is known as an extremely frequent bat in Iran. In this study, 76 presence points were identified and recorded in distribution range of species. Presence-only (Domain, Bioclim, and one-class

Trinuclear metal clusters of Co, Mn, and Co/Mn hybrid of [Mn3(O)(CH3COO)6-(py)3ClO4], [Co3(O)(CH3COO)6-(py)3ClO4], [Co2Mn(O)(CH3COO)6-(py)3ClO4], and [CoMn2(O)(CH3COO)6-(py)3ClO4] were prepared and characterized by FT-IR and UV–Vis spectroscopic techniques. These homogeneous catalysts were investigated in the epoxidation of cyclohexene in the presence of H2O2/O2 under mechanical stirring conditions

In this work, several new characterizations are given for the boundedness and compactness of weighted composition operators from weighted Bergman spaces into nth weighted-type spaces.

Modeling the high-T paramagnetic state of bulk UO\(_2\) by a non-spin-polarized calculation and neglecting the Hubbard-U correction for the f electrons in U atoms, the lattice thermal conductivity of bulk UO\(_2\) is investigated by the exact solution of the Boltzmann transport equation for the steady-state phonon distribution function. The resulting phonon dispersion shows good agreement with experiment

In this research, ZnAl2O4/SiO2 as nanocatalyst was produced via modified sol–gel procedure. The X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Fourier transform infrared spectroscopy (FT-IR) were performed to confirm the structure of nanocatalyst. The particle size was around 14 nm. Moreover, esterification of phthalic anhydride by 2-ethylhexanol

The effect of the thermal lens was demonstrated with all-optical switching for the new organic–inorganic hybrid salt: 1,1′-(ethylene-1,2-diyl)dipyridinium pentacyanidonitrosoferrate(II)pentahydrate. The development of thermal blooming of the probe laser beam at three input powers 20, 60, and 100 mW was observed. The evolution time of the thermal lens and the fitting of the experimental transient curve

In this work, the electron paramagnetic resonance (EPR) parameters (g-factors and A-constants) of the tetragonal VO2+ centers in LiHSO4 single crystals are theoretically investigated by the high-order perturbation formulae for these parameters based on two-spin–orbit-parameter model. Since the spin–orbit coupling coefficient of the ligand O2− is close to that of the central ion V4+ for the present

Recently, Lodhi and Mishra (J Comput Appl Math 319:170–187, 2017) presented the standard B-spline method based on quintic B-spline basis functions to solve a type of singularly perturbed boundary value problems (SPBVP). We note that their method provides only fourth-order convergence approximation to the solution of such problem. In this paper, we present a novel optimal B-spline technique, based on

This paper explores several characteristics of the pseudo-gamma (PG) distribution proposed by Mohsin et al. (J Appl Stat Sci 18(2):239–250, 2010) and finds it such a pliable distribution which approaches a variety of well-known distributions. The PG distribution is capable of describing the high probability at tails. An account of reliability features such as survival function, hazard rate function

In this paper, a Liénard-type differential equation with piecewise constant argument of generalized type is proposed. Existence and uniqueness of the solutions are investigated. Uniform asymptotic stability of the trivial solution is examined by the Lyapunov–Krasovskii method. The obtained theoretic results are exemplified and supported by a simulation.

In spite of point load method has been frequently used for assessment of the decay state of stones under weathering agents, its method in estimation of long-term durability of natural rocks remains limited. This study aims to assess the point load method efficiency in evaluation of long-term durability of limestone types due to frost action. For this reason, the frost process up to 100 cycles was applied

This research propounds a fractional-order Legendre functions operational matrix of fractional integration in order to solve the fractional delay differential equations. The fractional derivative is regarded in the Caputo sense. The suggested method is implemented to reduce the problem to the solution of a system of algebraic equations. Using the presented method, some examples are solved and numerical

In this work, pure and Bi-doped (0.01, 0.02 and 0.03) M Cu2Se thin films were deposited on glass substrate by simple chemical bath deposition method. The effect of Bi doping on Cu2Se films was analysed using their structural, morphological, optical and electrical properties recorded by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), diffuse reflectance spectra (DRS) and

The chemical co-precipitation method was used to prepare Ba0.88Sr0.12SO4:Dy1.5mol%,Tb1mol% nanocrystalline powder. Ba0.88Sr0.12SO4:Dy1.5mol%,Tb1mol% pellets were fabricated in order to measure gamma ray irradiation. A main TL glow peak around 207 °C, a small peak at 157 °C and a good linear response for doses in the range of 0.01–5 kGy were observed. The TLE spectra of the pellets were recorded at

Abstract A simple procedure for the synthesis of functionalized magnetic iron oxide supported sulfonic acid (Fe3O4@SiO2–Pr–NH2–SO2CH3) is reported. The product was characterized using Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), transmission electron microscopy (TEM)

Carbon nanotubes (CNTs) remain one of the most efficient reinforcing material for enhanced mechanical and electrical properties. In this study, the effects of multi-walled CNTs (MWCNTs) fillers on mechanical, structural, and electrical properties of polymethyl methacrylate (PMMA)/MWCNTs composites were studied. The PMMA/MWCNTs composites, containing varying MWCNTs concentration of 0.1, 0.3, and 0.5