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In the current work, organic cyclopenta-thiophene (CPT) based derivatives (FICR and FICD1-FICD5) were designed by the modulation of end-capped acceptor group of the reference molecule i.e., FICR, to explore their nonlinear optical (NLO) response. The effect of terminal acceptor and donor groups in the tailored compounds was explored by using DFT based quantum calculations. The UV-Vis analysis, frontier molecular orbitals (FMOs), transition density matrix (TDM), natural bond orbitals (NBOs), density of states (DOS), nonlinear optical (NLO) analyses were performed at M06/6-311G(d,p) functional. The LUMO-HOMO band gaps of FICD1-FICD5 were found to be smaller (1.75-1.92 eV) comparative to FICR (1.98 eV). Moreover, the global reactivity parameters (GRPs) were correlated with the results of other analyses. FICD2 and FICD5 with lowest band gap 1.73 and 1.75 eV showed less hardness (0.86 and 0.87 eV, respectively), high softness (0.58 and 0.57 eV -1 ), and larger absorption spectrum (815 and 813 nm) in gaseous phase and (889 and 880 nm) in solvent phase among all entitled compounds. All the designed chromophores (FICD1-FICD5) demonstrated a significant NLO response as compared to FICR. Particularly, FICD2 and FICD5 exhibited the highest average linear polarizability (<α>) [2.86 × 10 -22 and 2.88 × 10 -22 esu], first hyperpolarizability (β tot ) (8.43 × 10 -27 and 8.35 × 10 -27 esu) and second hyperpolarizability (γ tot ) (13.20 × 10 -32 and 13.0 × 10 -32 esu) values as compared to the other derivatives. In nutshell, structural modeling of CPT based chromophores with extended acceptors, can be significantly utilized to achieve potential NLO materials., (© 2024. The Author(s).)

In this paper, we have been study a hybrid nanofluid over an exponentially oscillating vertical flat plate. Therefore the fractional derivatives definition of Caputo-Fabrizio approach is applied to transform the classical model for this hybrid nanofluid to fractional model. Together with an oscillating boundary motion, therefore the heat transfer is cause as a result of the buoyancy force produce due temperature differences between the plate and the fluid. The dimensionless classical model is generalized by transforming it to the time fractional model using Caputo-Fabrizio time fractional derivative. Exact analytical solutions are obtained by using Laplace transform method to the set of dimensionless fractional governing equations, containing the momentum and energy equations subjected to the boundary and initial conditions. Numerical computations and graphical illustrations are used to checked the results of the Caputo-Fabrizio time-fractional parameter, the second-grade parameter, the magnetic parameter and the Grashof numbers on the velocity field. An assessment for time spin-off is shown graphically of integer order versus fractional-order for these non-Newtonian hybrid nanofluid through Mathcad software. The fluid velocity increases for increasing the value of the fractional parameter, second-grade parameter and Grashof number. Also for increasing the values of the MHD parameter the fluid velocity decreases., (© 2022. The Author(s).)

The paper aims to investigate the channel flow of second grade visco-elastic fluid generated due to an oscillating wall. The effect of heat and mass transfer has been taken into account. The phenomenon has been modelled in terms of PDEs. The constitutive equations are fractionalized by using the definition of the Caputo fractional operator with Fick's and Fourier's Laws. The system of fractional PDEs is non-dimensionalized by using appropriate dimensionless variables. The closed-form solutions of thermal and concentration boundary layers are obtained by using the Laplace and finite Fourier-Sine transforms, while the momentum equation is solved by a numerical approach by Zakian using [Formula: see text]. Furthermore, the parametric influence of various embedded physical parameters on momentum, temperature, and concentration distributions is depicted through various graphs. It is observed that the fractional approach is more convenient and realistic as compared to the classical approach. It is worth noting that the increasing values of [Formula: see text], [Formula: see text] and [Formula: see text] retard the boundary layer profile. For instance, this behaviour of [Formula: see text] is significant where boundary control is necessary. That is, in the case of resonance, the physical solution may be obtained by adding the effect of MHD. The Reynolds number is useful in characterising the transport properties of a fluid or a particle travelling through a fluid. The Reynolds number is one of the main controlling parameters in all viscous flow. It determines whether the fluid flow is laminar or turbulent. The evolution of the rate of heat, mass transfer, and skin friction on the left plate with various physical parameters are presented in tables. These quantities are of high interest for engineers. Keeping in mind the effect of various parameters on these engineering quantities, they make their feasibility reports., (© 2022. The Author(s).)

This study was aimed at evaluating the acute and subchronic toxicity of ultrasonic extract of Dichroae radix (UEDR) in mice and rats. High performance liquid chromatography (HPLC) and thin layer chromatogrephy (TLC) were used to detect β-dichroine and α-dichroine in UEDR for quality control. The levels of β-dichroine and α-dichroine in UEDR were 1.46 and 1.53 mg/g, respectively. An oral LD 50 of 2.43 g/kg BW was observed in acute toxicity test. After 28-day repeated oral administration, compared with the control group, treatment-related changes in body weight (BW) and body weight gain (BWG), lymphocyte counts and ratios, as well as in the relative organ weights (ROWs) of liver, kidney, lung, and heart, were detected in the middle- and high-dose groups (P < 0.05, P < 0.01), no differences were noted in the serum biochemical parameters and necropsy examinations in both sexes at all doses. Histopathological examinations exhibited UEDR-associated signs of toxicity or abnormalities. After 14 days withdrawal, no statistically significant or toxicologically relevant differences were observed in any of the UEDR-treated groups, and the hispathological lesions in the high-dose group were alleviated. Findings showed that long-course and high-dose of UEDR administration was toxic, and showed dose-dependence, the toxic damage was reversible.

Artificial sheet materials, known as MetaSurfaces, have been applied to fully control both space and surface waves due to their exceptional abilities to dynamically tailor wave fronts and polarization states, while maintaining small footprints. However, previous and current designs and manufactured MetaSurfaces are limited to specific types of surfaces. There exists no general but rigorous design methodology for MetaSurfaces with generic curvature. The aim of this paper is to develop an analytical approach to characterize the wave behavior over arbitrary curvilinear MetaSurfaces. The proposed method allows us to fully characterize all propagating and evanescent wave modes from the MetaSurfaces. We will validate the proposed technique by designing, realizing and testing an ultrathin MetaSurface cloak for surface waves. Good results are obtained in terms of bandwidth, polarization independence and fabrication simplicity.

Understanding the enhancement of charge carrier generation and their diffusion is imperative for improving the efficiency of optoelectronic devices particularly infrared photodetectors that are less developed than their visible counterpart. Here, using gold nanorods as model plasmonic systems, InAs quantum dots (QDs) embedded in an InGaAs quantum well as an emitter, and GaAs as an active mediator of surface plasmons for enhancing carrier generation and photon emission, the distance dependence of energy transfer and carrier diffusion have been investigated both experimentally and theoretically. Analysis of the QD emission enhancement as a function of distance reveals a Förster radius of 3.85 ± 0.15 nm, a near-field decay length of 4.8 ± 0.1 nm and an effective carrier diffusion length of 64.0 ± 3.0 nm. Theoretical study of the temporal-evolution of the electron-hole occupation number of the excited states of the QDs indicates that the emission enhancement trend is determined by the carrier diffusion and capture rates.

Transformation optics (TO) offers a geometrical approach in designing optical components of any shapes. Although it has been proven to be a versatile and robust mathematical tool, TO has, however, limited control over electromagnetic (EM) field polarization in the process of coordinate transformation. Such a technique can be extended to a so-called "Field transformation (FT)" which provides direct control over the impedance and polarization signature of an arbitrary object. In this work, we demonstrate a FT application by designing and manufacturing a novel waveplate, which defies the fundamental limit of bandwidth and incident angles and has the ability of converting between TE (transverse electric) and TM (transverse magnetic) as well as LCP (left-handed circular polarization) and RCP (right-handed circular polarization). Such a waveplate can also be applied to different operating modes for both transmitted and reflected waves by adjusting its thickness and adding an optional metallic ground plane. The proposed design approach presents a remarkable degree of advance for designing future devices with arbitrary polarization controls, artificial waveguides or antenna substrates and polarization-enabled resonators with angle-insensitive functionalities. Our approach has far reaching implications applicable from radio to optical frequencies.

In the last decade, a technique termed transformation optics has been developed for the design of novel electromagnetic devices. This method defines the exact modification of magnetic and dielectric constants required, so that the electromagnetic behaviour remains invariant after a transformation to a new coordinate system. Despite the apparently infinite possibilities that this mathematical tool introduces, one restriction has repeatedly recurred since its conception: limited frequency bands of operation. Here we circumvent this problem with the proposal of a full dielectric implementation of a transformed planar hyperbolic lens which retains the same focusing properties of an original curved lens. The redesigned lens demonstrates operation with high directivity and low side lobe levels for an ultra-wide band of frequencies, spanning over three octaves. The methodology proposed in this paper can be applied to revolutionise the design of many electromagnetic devices overcoming bandwidth limitations.