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Takes a look at the state of Arab society. Classifies Arab individuals into eight categories – traditionalist, spectator, idealist, illusionist, transitional, revivalist, manipulator, and existentialist. Explores each of these in more depth, providing some specific illustrative examples. Claims that work values have changed in Arab society, with the new generation taking part in political and economic decision making. Reflects on the implications this could have for multinational corporations. Concludes that Arab society is in transition, discarding its old tribal and traditionalist beliefs to move towards the basis for a more modern economy. Provides some tables summarizing each typology of individual and the attributes required to conduct business successfully.

The purpose of this paper is to introduce the phase-lag models (Lord-Shulman, dual-phase-lag and three-phase-lag) to study the effect of memory-dependent derivative and the influence of thermal loading due to laser pulse on the wave propagation of generalized micropolar thermoelasticity. The bounding plane surface is heated by a non-Gaussian laser beam with a pulse duration of 10 nanoseconds.

The normal mode analysis technique is used to obtain the exact expressions for the displacement components, the force stresses, the temperature, the couple stresses and the micro-rotation. Comparisons are made with the results predicted by three theories of the authors’ interest. Excellent predictive capability is demonstrated at a different time also.

The effect of memory-dependent derivative and the heat laser pulse on the displacement, the temperature distribution, the components of stress, the couple stress and the microrotation vector have been depicted graphically.

Some particular cases are also deduced from the present investigation.

The numerical results are presented graphically and are compared with different three theories for both in the presence and absence of memory-dependent effect and with the results predicted under three theories for two different values of the time.

The purpose of this paper is to discuss the synthesis of new azo disperse dyes containing pyridine ring for dyeing acetate polyester and other fibres.

Cycloaddition reaction of 3-formylchromone (Compound 1) with ethyl vinyl ether (Compound 2) afforded 3-ethoxy-4,4a-dihyro-3H,10H-pyrano[4,3-b]chromen-10-one (Compound 3). Reaction of 3 with aqueous ammonium sulphite in ethanol furnishes 3-(2-hydroxybenzoyl)pyridine (Compound 5). Compound 5 was fully characterised by spectroscopic techniques. Ten arylazo derivatives of Compound 6 have been prepared for use as dyestuffs. The effect of the nature and orientation of substituents in the diazonium component on the colour of azo dyes is discussed. Dyeing performance of the dyes on different fibres has also been assessed.

Most of the dyes showed good affinity to polyester fibres. On the other hand, polyacrylic fibres were only stained to weak shades.

No details regarding the synthesis and dyeing performance of such dyes are reported before in the literature.

The purpose of this paper is to study the effects of thermal radiation and homogeneous-heterogeneous reactions in the three-dimensional hybrid nanofluid flow past a permeable stretching/shrinking sheet.

The combination of aluminum oxide (Al₂O₃) and copper (Cu) nanoparticles with total volumetric concentration is numerically analyzed using the existing correlations of hybrid nanofluid. With the consideration that both homogeneous and heterogeneous reactions are isothermal while the diffusion coefficients of both autocatalyst and reactant are same, the governing model is simplified into a set of differential (similarity) equations.

Using the bvp4c solver, dual solutions are presented, and the stability analysis certifies the physical/real solution. The findings show that the suction parameter is requisite to induce the steady solution for shrinking parameter. Besides, the fluid concentration owing to the shrinking sheet is diminished with the addition of surface reaction.

The present findings are novel and can be a reference point to other researchers to further analyze the heat transfer performance and stability of the working fluids.

objective of the present investigation is to examine the influence of Hall on the peristaltic mechanism of Johnson-Segalman fluid in a heated channel with elastic walls. The transmission of heat is carried out. Relevant equations are computed for heat transfer coefficient, temperature and velocity. Low Reynolds number assumptions and long wavelength are employed. The interpretation of various parameters is analyzed. The results indicate that the heat transfer coefficient, temperature and velocity are larger for viscous material in comparison with Johnson-Segalman material.

The transmission of heat is carried out. Relevant equations are computed for heat transfer coefficient, temperature and velocity. Low Reynolds number assumptions and long wavelength are employed. The interpretation of various parameters is analyzed. The results indicate that the heat transfer coefficient, temperature and velocity are larger for viscous material in comparison with Johnson-Segalman material.

The formulation of paper is executed as follows. Section 2 comprises problem summary and mathematical design. Solution methodology is discussed, and expressions for temperature, velocity and coefficient of heat transfer are derived in Section 3. Graphical outcomes for the parameters are reported in Section 4. Conclusions are outlined in Section 5.

Peristaltic phenomenon of fluids has a definite role in many physiological, industrial and engineering processes. The mechanical devices for instance finger and roller pumps operate via this process, and it is quite significant for vasomotion of blood vessels, consumption of food via esophagus, chyme flow in gastrointestinal zone, toxic liquid flow in nuclear industry and transport of corrosive fluids.

Literature review witnesses that information about peristalsis of conducting fluid in a heated channel with flexible walls and Hall effect is scarce. So, our goal is to discuss the peristaltic activity of non-Newtonian fluids in flexible channel. Johnson-Segalman fluid is taken into account. This model is used to allow non-affine deformations. Experimentalists relate “spurt” with wall slip. That is why the work presented is original.

This study investigates the flow and heat transfer in a magnetohydrodynamic (MHD) ternary hybrid nanofluid (HNF), considering the effects of viscous dissipation and radiation.

The transport equations are transformed into nondimensional partial differential equations. The local nonsimilarity (LNS) technique is implemented to truncate nonsimilar dimensionless system. The LNS truncated equation can be treated as ordinary differential equations. The numerical results of the equation are accomplished through the implementation of the bvp4c solver, which leverages the fourth-order three-stage Lobatto IIIa formula as a finite difference scheme.

The findings of a comparative investigation carried out under diverse physical limitations demonstrate that ternary HNFs exhibit remarkably elevated thermal efficiency in contrast to conventional nanofluids.

The LNS approach (Mahesh et al., 2023; Khan et al., 20223; Farooq et al., 2023) that we have proposed is not currently being used to clarify the dynamical issue of HNF via porous media. The LNS method, in conjunction with the bvp4c up to its second truncation level, yields numerical solutions to nonlinear-coupled PDEs. Relevant results of the topic at hand, obtained by adjusting the appropriate parameters, are explained and shown visually via tables and diagrams.

The paper aims to the preparation of novel disperse dye based on azo salicylaldehyde derivatives TF-A [2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde] and full evaluation of their use as disperse dye TF-ASC [bis 2-hydroxy-5-((3-(trifluoromethyl)phenyl)diazenyl)benzaldehyde Schiff base with 4,4'-methylenedianiline] for dyeing polyester fabric at various conditions.

The dispersed dye was synthesized via Schiff base condensation in the presence of ceric ammonium nitrate cerium ammonium nitrate 10 mmole% as an eco-friendly catalyst at room temperature. The chemical structure of the prepared dye was characterized via elemental analysis, Fourier-transform infrared spectroscopy, 1H- and 13 C-NMR spectroscopic analysis tools. This study thoroughly examined the dyeing of disperse dye TF-ASC on polyester at various conditions. The characteristics of dyed polyester fabric were measured by colour measurements, as well as light, washing, crock fastness and finally, colour strength. The discrete fourier transform (DFT) theoretical studies, including E_HOMO, E_LUMO and optimized geometrical structure, were assumed and discussed in detail.

The results showed that the synthesized organic dye TF-ASC was highly functional and appropriate for this kind of dyeing method. The dyeing fabrics obtained from disperse dye TF-ASC, properties possess high colour strength as well as good overall fastness properties. These dyes had a high affinity for polyester fabric, with just a tiny change in dye affinity when the pH was changed, even under alkaline circumstances. The dye levelness and shade depth of the colour results were good, and there were a variety of hues from light brownish yellow to deep brownish yellow. The results obtained from DFT computational studies such as E_HOMO, E_LUMO, optimized structure, diploe moment µ and electrophilicity index deduced that prepared organic dye TF-ASC is more applicable as a dispersed dye.

This research is significant because it provides a new dye for dyeing polyethylene terephthalate fibres with exceptional brightness and levelness; the method of preparation is a useful pathway due to its being known as a green chemistry method.

The purpose of this paper is to prepare new disperse dyes and apply for dying polyester fabrics.

The synthetic reaction was carried out through two steps: preparation of arylhydrazones and alkylation using enaminone and dimethylaminovinyl-pyridazine. The high temperature method was used to apply these dyes to polyester fibres.

The study revealed that there is a significant effect of the new prepared disperse dyes on polyester fabrics. The structures of the prepared dyes were established based on elemental analysis and spectral data (infra red (IR), mass spectrometry (MS) and proton nuclear magnetic resonance (¹H-NMR), carbon 13^th nuclear magnetic resonance (¹³C-NMR)).

Disperse dyes containing heterocyclic moiety have attracted great academic and industrial attention owing to their significant. The potential of using disperse dyes easily prepared from arylhydrazones are promise broad applications for these dyes.

The presence of N-thienyl and N-pyridazinyl in the structure of the synthesised disperse dyes would be expected to add the bioactivity advantage. Also, it can be used in formulating the antimicrobial fabrics.

The N-thienyl and N-pyrdiazinyl derivatives of azo dyes are expected to be superior to in the application for fabrics. It may be useful for other applications like painting.

This paper helps to synthesise novel thiophene or pyridazine-based dyestuff for application in dying properties on polyester fabric and study their fastness properties.

The evaluation of high thermal efficiency has actively highlighted the unique behaviour of hybrid nanofluid. Thus, the purpose of this paper is to emphasize the hybrid nanofluid’s stagnation point in three-dimensional flow with magnetic field.

The defined ordinary differential equations systems are addressed using the bvp4c solver.

The results indicate that using dual solutions is possible as long as the physical parameters remain within their specified ranges. Hybrid nanofluid flow has been recognised for its superior heat transfer capabilities in comparison to both viscous flow and nanofluid flow. Furthermore, it has been demonstrated in the current study that augmenting the volume concentration of nanoparticles leads to a corresponding enhancement in the rate of heat transfer. When the velocity gradients ratio is augmented, there is a corresponding reduction in the thermal performance. The separation value grows as the magnetic parameter rises, which signifies the expansion of the boundary layer.

The originality of the paper highlights the general mathematical hybrid model of the three-dimensional problem with the magnetohydrodynamics (MHD) effect in the stagnation point flow. The comprehensive examination of the suggested model has not yet been thoroughly addressed in prior research.

The purpose of this paper is to numerically investigate the hybrid nanofluid flow with the imposition of magnetohydrodynamic (MHD) and radiation effects alongside the convective boundary conditions over a permeable stretching/shrinking surface.

The mathematical model is formulated in the form of partial differential equations (PDEs) and are then transformed into the form of ordinary differential equations (ODEs) by using the similarity variables. The deriving ODEs are solved numerically by using the bvp4c solver in MATLAB software. Stability analysis also has been performed to determine the stable solution among the dual solutions obtain. For method validation purposes, a comparison of numerical results has been made with the previous studies.

The flow and the heat transfer of the fluid at the boundary layer are described through the plot of the velocity profile, temperature profile, skin friction coefficient and local Nusselt number that are presented graphically. Dual solutions are obtained, but only the first solution is stable. For the realizable solution at the shrinking surface, the proliferation of nanoparticle volume fraction (copper) and magnetic (magnetohydrodynamics) parameters can impede the boundary layer separation. Also, Biot number could enhance the temperature profile and the heat transfer rate at the shrinking surface region. The incrementation of 0.1% of Biot number has enhanced the heat transfer rate by approximately 0.1% and the incrementation of 0.5% volume fraction for copper has reduced the heat transfer rate by approximately 0.17%.

The presented model and numerical results are original and new. It can be used as a future reference for further investigation and related practical application. The main contribution of this investigation includes giving the initial prediction and providing the numerical data for the other researchers for their future reference regarding the impacts of nanoparticles volumetric concentration towards the main physical quantities of interest in the presence of magnetic and radiation parameters with the convective boundary conditions.