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

In this paper, we introduce a family of analytic functions given by (psi _{A,B}(z):= dfrac{1}{A-B}log {dfrac{1+Az}{1+Bz}},) which maps univalently the unit disk onto either elliptical or strip domains, where either (A=-B=alpha) or (A=alpha e^{igamma }) and (B=alpha e^{-igamma }) ((alpha in (0,1]) and (gamma in (0,pi /2])). We study a class of non-univalent analytic functions defined by ({{mathcal {F}}}[A,B]:=left{ fin {{mathcal {A}}}:left( dfrac{zf'(z)}{f(z)}-1right) prec psi _{A,B}(z)right}). Further, we investigate various characteristic properties of (psi _{A,B}(z)) as well as functions in the class ({{mathcal {F}}}[A,B]) and obtain the sharp radius of starlikeness of order (delta) and univalence for the functions in ({{mathcal {F}}}[A,B]). Also, we find the sharp radii for functions in ({{{mathcal {B}}}}{{{mathcal {S}}}}(alpha ):={fin {{mathcal {A}}}:zf'(z)/f(z)-1prec z/(1-alpha z^2),;alpha in (0,1)}), ({{mathcal {S}}}_{cs}(alpha ):={fin {{mathcal {A}}}:zf'(z)/f(z)-1prec z/((1-z)(1+alpha z)),;alpha in (0,1)}), and others to be in the class ({{mathcal {F}}}[A,B].)

In this work, the isoscalar giant monopole resonance (ISGMR) of even-A Cadmium (^{110,112,114,116}Cd) isotopes has been studied in the framework of self-consistent Skyrme Hartree–Fock–Bardeen, Cooper and Schrieffer (HF–BCS) and quasiparticle random phase approximation (QRPA). Ten Skyrme-type parameters are used in the calculations, i.e., SkP, eMSL09, MSL0, T44, BSK20, Ska, SV, QMC2, SII and SGOI having different values of the nuclear matter incompressibility modulus K_MN. The calculated strength distributions, centroid energy E_cen, constrained energy E_con, and scaling energy E_s of ISGMR are compared with available experimental data. It has found that the interactions with low incompressibility value more suitable to describe the ISGMR strength distributions for all isotopes, where the high K_NM shift the peak to upper energy and low strength while the low K_NM shift it to less energy and upper strength.

The production of molybdenum-99 (⁹⁹Mo) as the parent of radiopharmaceutical ^99mTc is the most widely used in the world. More than 90% of ⁹⁹Mo produced worldwide is obtained through the fission of ²³⁵U. The Hot Cells should be used to extract the ⁹⁹Mo from LEU targets irradiated in the reactor. In this study, the spectrum of gamma rays emitted from LEU targets was calculated for 4 and 6 days of irradiation and one day of cooling separately. Then for these conditions, the evaluation of zoning, the dose limit classification diagram, dose mapping, and the contour distribution map of the dose rate of the hot cell building, for hot cells with 60, 70, 80, and 90 cm barite concrete walls were done with MCNP6 code simulations. The results could be useful for safety management and control, creating safe and controlled areas for employees, and preventing unnecessary contact with radiation for daily traffic are determined. The operating room of a building with 90 cm hot cell walls was found completely safe for ⁹⁹Mo production.

This article suggests an accurate computational approach based on meshless barycentric rational interpolation and spectral method to solve a class of nonlinear stochastic fractional integro-differential equations. These equations have various applications in many aspects of science. The nonlinearity of the equations and the existence of the random factors make their most existing numerical simulations difficult. Therefore, developing an efficient and accurate solver is a challenge. The method introduced in this study converts the given problem into a set of algebraic equations that are nonlinear in nature. Hence, the difficulty of addressing the problem mentioned above is greatly diminished. This article highlights the advantages of meshless barycentric rational interpolation, such as their meshless nature and simplicity of usage in nonlinear problems and the high accuracy of this technique. Due to the random nature of the studied problems, the exact solutions to these problems are not available. Therefore, to ensure the accuracy of the calculated solutions, we provide an error evaluation that can be applied to different problems. We assess the precision of this meshless technique through numerical examples. The simple process of this method clearly reveals its superiority over other available methods. Furthermore, a noteworthy innovation in this research is achieving satisfactory accuracy with a small number of interpolation nodes and basis functions.

Preformed cluster model is applied to examine the ground state decay of various even isotopes of Z = 113 (Nh) parent nucleus with A = 278–292. Within the Skyrme energy density formalism, SVand SAMi Skyrme forces are used to identify the probable clusters from the considered emitters by investigating the fragment (cluster) mass yield (or cluster formation probability P₀). The calculations suggest that, for ^278–292113 parent nuclei, the maxima at cluster region arises due to the shell closure effects around neutron magic number N = 50. However, with the increase in mass of the emitter, the magicity of daughter also start to appear around N = 126.

One of the most important issues in nuclear astrophysics is the lithium problem, which is the disagreement between the theoretical and experimental values of the lithium abundance of the Big Bang nucleosynthesis. Solving this problem or establishing compatibility between the two mentioned values can be considered as the confirmation of one part of the Big Bang Theory. Bayesian statistics is one of the most recent methods used to improve the calculation accuracy of the abundance of primary nuclei after the Big Bang and their reaction rates. In this study, Bayesian statistics is used to fit the S-factor and also calculate the rate of astrophysical reactions d(p,γ)³He and ³He(d,p)⁴He using available experimental data. The results of this study are in good agreement with similar Bayesian researches, and can be considered as an improvement compared to the results of the other (non-Bayesian) methods.

Saturated incidence rates and treatment responses are essential in epidemiology and clinical research. They signify peak event occurrences in a population, aiding in disease understanding and intervention planning. This study proposes a mathematical model of COVID-19, focusing on the impact of saturated incidence rates and treatment responses on its dynamical transmission. Via qualitative analysis, the existence and uniqueness of the model’s solution are verified, a positive invariant region is established, and the local stability analysis highlights the model’s resilience to minor perturbations. The model solution is obtained utilizing the homotopy perturbation method, and simulations with Maple 18 software reveal that increasing treatment intensity might not result in significant additional decrease in the number of infections, particularly in situations where the spread of infection is uncontrolled. Thus, the finding underscores the need to refine treatment strategies through a tailored approach and to optimize preventive measures.

The dispersion, threshold, and gain characteristics of the Brillouin scattered Stokes mode (BSSM) in ion-implanted semiconductor quantum plasmas are analytically investigated using coupled mode theory. Taking into account that the origin of stimulated Brillouin scattering lies in nonlinear induced polarisation of the medium, expressions are derived for complex effective Brillouin susceptibility (due to electrons and implanted colloids) and consequently the threshold pump amplitude and the gain constant of BSSM. Inclusion of quantum effects (QEs) is done via quantum correction term in the hydrodynamic model of semiconductor plasmas. QEs modify the dispersion, threshold and gain characteristics of BSSM in ion-implanted semiconductor plasmas. In contrast to the threshold and gain characteristics of BSSM, which are impacted only by electrons and are unaffected by implanted charged colloids, the Brillouin susceptibility caused by implanted colloids has a significant impact on the dispersion characteristics of BSSM. Finally, an extensive numerical study of the n-InSb/CO₂ laser system is performed for two different cases: (i) without QEs and (ii) with QEs. In both cases, the analysis offers two achievable resonances, at which the changes of sign as well as an enhancement of real part of effective Brillouin susceptibility and an enhancement of effective Brillouin gain constant are obtained. When QEs are included in the analysis, the entire spectrum shifts towards decreased levels of electron and colloidal carrier concentration.

Using the Coulomb Modified Glauber (CMG) model for interactivity of (^{84}{text {Kr}}_{36}) with NED (Nuclear Emulsion Detector) nuclei at 1 A GeV, we have examined the total nuclear reaction cross-section (CS) for target participants [(P_textrm{targ})], projectile participants [(P_textrm{proj})], and binary collisions [(B_textrm{C})] in this paper. We noted that there is a good compatibility between the average reaction CS with nuclear medium influence and the experimental findings. These estimated CS for nuclear reactions, [(P_textrm{proj})], [(P_textrm{targ})] and [(B_textrm{C})], are tally with the various target groups of the nuclear emulsion nuclei. We have also focused on the azimuthal correlation of gray particles and black particles, shower particles and their dependence on the projectile mass ((A_textrm{p})) at relativistic energy. The parameters which we have studied are the asymmetry coefficients ((<alpha>) and A). We have observed that the correlation increases linearly with (A_textrm{p}).

We consider analytic functions of the form (f(z)=sum _n{a_n z^n}) with (|f(z)|le 1) defined on the unit disc (mathbb {D}:={zin mathbb {C}:|z|<1}). Due to studies on the Bohr phenomenon concerning this class of functions, and recent results on the Bohr inequality of some integral operators, we are interested in Bohr inequalities pertaining to integral transforms. We first obtain a Bohr-type inequality for the (discrete) Fourier transform acting on the functions f defined above, alongside the associated Bohr radius. We find that this inequality is sharp, and that the constant dictating the Bohr radius cannot be improved. We obtain a secondary result by finding an expression for (a:=|a_0|) that maintains the Bohr inequality even if (r:=|z|) grows past the Bohr radius. We also investigate the behaviour of the Fourier transform of f as (rrightarrow 1), by finding the limiting bound for the aforementioned transform. We prove that this bound is actually also sharp. We then study the (discrete) Laplace transform of f and obtain its relevant Bohr inequality.