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•Here comparative work is presented for nanofluid and hybrid nanofluid.•The flow behavior is observed over a vertical cylinder surface.•Three types of nanoparticles aluminum oxide (Al2O3), copper (Cu) and nickel (Ni) are accounted.

•Here peristaltic transport phenomenon is examined via asymmetric channel.•Ellis fluid model is utilized for the flow behavior.•Streamlines is presented.•Nonlinear radiative heat flux is used in energy expression.

•Oblique stagnation point flow over a stretching cylinder is considered.•Thermal and concentration slip conditions are imposed.•Runge-Kutta-Fehlberg method is used for the numerical solution.•The effects of thermal radiation and chemical reaction are presented.•Local Nusselt and Sherwood numbers are presented.

Many physiological ducts, like sperm vessels, intestines, common bile ducts, ducts of salivary glands, and ducts in the repertory system, are common ducts in which transport occurs due to the propagation of complex waves on the boundary. Electroosmotic flow phenomena are significant in membrane separation processes, protein and peptide delivery, iontophoresis in drug delivery through physiological ducts, and a lot of application in plant physiology regarding pressure control in xylem and phloem vessels. The aim of this theoretical study is to analyze the thermal characteristics of physiological fluid characterized by the Carreau-Yasuda model in a complex wavy channel. The two agents of flow, i.e., the propagation of complex waves on the walls of the channel and the electric field in the axial direction, are considered. Different zeta potentials at both walls of the asymmetric channel are employed. Basic conservation laws, along with the Poisson-Boltzmann equation, are utilized to model the problem in the Cartesian coordinate system. Theoretical and biological assumptions like greater wavelength, lubrication transport, and Debye-Hückel linearization transform the governing equations of PDE into a coupled system of ODE. The shooting method is used, which is Solve, a built-in function in the computational software Mathematica to compute the stream function, temperature profile, concentration profile, and various flow and heat transfer characteristics. The impact of various penetrating parameters is described through plots. The magnitude of the velocity profile is increased near the center of geometry by increasing the electroosmotic parameter in the lower half of the regime. Then the Sherwood number and the Bejan number show enhanced behavior by increasing the electroosmotic parameter. The current analysis predicts dynamic applications in thermodynamical systems, cooling systems, biochemistry, and drug delivery systems.

Single crystal Co(H2O)2Ni(CN)4·4H2O has been successfully synthesized by a slow diffusion method using trisodium citrate dihydrate for controlling the nucleation rate and the crystal growth. The single crystal X-ray diffraction results show the obtained crystals with a two-dimensional orthorhombic unit cell, assembled from cationic Co ions and anionic [Ni(CN)4]2-units connected by bridging cyanide groups.Single crystal Co(H2O)2Ni(CN)4·4H2O is successfully synthesized by a slow diffusion method using trisodium citrate dihydrate for controlling the nucleation rate and the crystal growth. The single crystal X-ray diffraction results show the obtained crystals have a two-dimensional orthorhombic unit cell, built up of cationic Co ions and anionic [Ni(CN)4]2-units connected by a bridging cyanide compound.

The phenomenon of bioconvection in nanomaterials presents novel applications in the biotechnology, biofuels, enzymes, biomedical engineering and energy systems. Current exploration explores the applications of bioconvection in Homann flow of nanofluid due to spiraling of disk theoretically. The generalized model namely tangent hyperbolic fluid is used to predicts the rheological and thermal impact. The stability of nanofluid is ensured with interaction of motile microorganisms. The Boungrino nanofluid model with thermophoresis and Brownian motion features is used to perform the analysis The thermal distribution of nanofluids is proceeded by utilizing the zero mass thermal constraints. The similarity variables are introduced in order to estimating the dimensionless formulation. The Keller Box method with higher efficiency is imposed with implicit finite difference numerical algorithm. The main observations reveal that with enhancing the radial velocity and azimuthal velocity decreases with increasing sparling angle. For highly viscous case, a decrement in the azimuthal velocity has been observed.

We have investigated the influence of Ag doping on zinc oxide thin films. Pure and Ag doped, preferentially oriented transparent zinc oxide thin films were prepared by sol gel technique on a glass substrate using diethyl amine as a stabilizer. The X-ray diffraction analysis revealed that the films with hexagonal wurtzite type structure were polycrystalline in nature with a preferred grain orientation in the 101 direction. The crystallite sizes decreased from 34 nm to 27 nm after silver doping. Both photoluminescence and optical transmission measurements showed that the band gap increased after the Ag doping. The structure and optical characterization studies clearly indicated the incorporation of Ag in ZnO. Hence, the observed increase in the optical band gap and decrease in crystallite size can be directly attributed to the effect of Ag ion incorporation into the ZnO lattice.

In this paper we studied the laser-induced crater depth, mass, and emission spectra of laser-ablated high-density polyethylene (HDPE) polymer using the laser-induced plasma spectroscopy (LIPS) technique. This study was performed using a Nd:YAG laser with 100 mJ energy and 7 ns pulse width, focused normal to the surface of the sample. The nanoscale change in ablated depth versus number of laser pulses was studied. By using scanning electron microscope (SEM) images, the crater depth and ablated mass were estimated. The LIPS spectral intensities were observed for major and minor elements with depth. The comparison between the LIPS results and SEM images showed that LIPS could be used to estimate the crater depth, which is of interest for some applications such as thin-film lithography measurements and online measurements of thickness in film deposition techniques.

In this work, laser induced breakdown spectroscopy (LIBS) is used to investigate soil samples collected from different desert areas of Riyadh city in Saudi Arabia. Both qualitative analysis and plasma parameters are studied via the observed LIBS spectra. These experiments have been done using a Spectrolaser-7000 system with 50 mJ fundamental wavelength of Nd:YAG laser and detection delay time of 1 microsecond. Many spectral lines are highly resolved for many elements like Al, Fe, Mg, Si, Mn, Na, Ca and K. The electron temperatures Te and electron densities Ne, for the constituent of generated LIBS plasma, are determined for all the collected samples. It is found that both Te and Ne vary from one desert area to other. This variation is due to the change of the elemental concentration in different desert areas that affects the sample's matrices. Time dependent measurements have also been performed on the soil samples. While the signal-to-base ratio (SBR) reached its optimal value at 1 microsecond, the plasma parameters Ne and Te reach values of $4{\times}10^{17}cm^{-3}$ and 9235 K, respectively, at 2.5 microsecond. The later indicate that the plasma cooling processes are slow in comparison to the previously observed results for metallic samples. The observed results show also that in the future it is possible to enhance the exploitation of LIBS in the remote on-line environmental monitoring application, by following up only the values of Ne and Te for one element of the soil desert sample using an optical fiber probe.

This numerical study elaborate the Von Karman swirling flow of second grade fluid having temperature dependent viscosity. The governing non-linear partial differential equations converted into non-dimensional ordinary differential equations using suitable transformations. The system of resulting ordinary differential equations are solved using the well-known implicit finite difference scheme. Then the results are presented graphically and the impact of various involved parameters on velocity, temperature, and concentration profiles. Redial and transversal shear stress on the surface of the disk, local Nusselt and Sherwood numbers are presented through tables. It is found that Variable viscosity parameter θδ, Thermorpheratic parameter, Brownian motion and the suction parameter oppose the motion while the Non-Newtonian fluid parameter and the Prandtl number assist the fluid motion. Variable viscosity parameter enhance both temperature and concentration fields but reduces the magnitude of radial and transversal shear stresses. The results are compared with the existing results and found to be an excellent agreement.

In this paper peristaltic motion of an Oldroyd-4 constant nanofluid under the influence of Buoyancy forces is taken into account. The Buongiorno model is utilized to see the effects of Brownian motion and thermophoresis on the different features of the flow, heat transfer and concentration. In order to facilitate the solution of modeled equations first the governing equations are transformed to system of ordinary differential equations under the assumption of long wavelength and low Reynolds number. The resulting equations are solved using shooting method along with fourth order R. K. method. It is observed that the amplitude of heat flux rises and effective moment of nanoparticles from wall to the center line of the channel which enhance the thermal conductivity at the wall. This is due to the increase in the kinetic energy and Brownian motion. The effects of different parameters are illustrated through graphs and tabulated data is given to compare the effects of shear stress on walls of the channel with Newtonian fluids.