This article reports on the International Nanofluid Property Benchmark Exercise, or INPBE, in which the thermal conductivity of identical samples of colloidally stable dispersions of nanoparticles or “nanofluids,” was measured by over 30 organizations worldwide, using a variety of experimental approaches, including the transient hot wire method, steady-state methods, and optical methods. The nanofluids tested in the exercise were comprised of aqueous and nonaqueous basefluids, metal and metal oxide particles, near-spherical and elongated particles, at low and high particle concentrations. The data analysis reveals that the data from most organizations lie within a relatively narrow band (±10% or less) about the sample average with only few outliers. The thermal conductivity of the nanofluids was found to increase with particle concentration and aspect ratio, as expected from classical theory. There are (small) systematic differences in the absolute values of the nanofluid thermal conductivity among the various experimental approaches; however, such differences tend to disappear when the data are normalized to the measured thermal conductivity of the basefluid. The effective medium theory developed for dispersed particles by Maxwell in 1881 and recently generalized by Nan et al. [J. Appl. Phys. 81, 6692 (1997)], was found to be in good agreement with the experimental data, suggesting that no anomalous enhancement of thermal conductivity was achieved in the nanofluids tested in this exercise.

A Benchmark Study on the Thermal Conductivity of Nanofluids

The origin of plant cell and tissue culture can be found in a treatise published during the mid-18th century, entitled La Physique des Arbes, that describes the formation of callus tissue following the for mation of a ring of cortex from elm trees. Over the next two centuries, the discovery of plant growth hormones, in particular auxins and cytokinins, and detailed analyses on the nutritional requirements of plants, led to the formulation of media that could maintain actively dividing cultures derived from gymnosperms, and both dicotyledon ous and monocotyledonous angiosperms. However, much of the prog ress and technological development in the in vitro propagation of plant cells, tissues, and organs has occurred during the last 25 years. Recently, plant tissue culture techniques have been used as basic tools in the rapidly expanding field of plant biotechnology for the development and clonal propagation of new and/or improved plant varieties. Plant tissue culture is used for the micropropagation of commercially valuable cultivars that include ornamentals, oil palm, Glycyrrhiza, Pyrethrum, pine, Eucalyptus, sugar cane, and potatoes. Cultured plant tissue is also used for the selection of cells and, ul timately, the regeneration of plants that are tolerant to physical stresses such as pathogens, drought, and temperature extremes, and to chemical stress agents such as salinity, herbicides, proteins, and pyrethrins. In addition, new plants have been produced by the fusion of protoplasts prepared from cultured cells of different species in cluding sunflower and french bean, tomato and potato, and various cultivars of Datura. Finally, bacterial vectors and various mechanical methods have been used to introduce foreign genes into cultured plant tissues. Genetic transformation can result in profound changes in the phenotype and/or biochemical profile of the regenerated trans genic plants that are not characteristic of the wild type. An impressive variety of technologies in tissue culture, genetic manipulation, and molecular biology have been developed for nu merous plant species. Many of these techniques, sometimes referred to as plant biotechnology, have been extensively summarized and compiled in a well-balanced collection of easy-to-follow protocols presented in three separate, but complimentary, volumes. Plant Cell, Tissue and Organ Culture consists of 22 chapters (with 86 figures) and 5 appendices. The chapters cover critical aspects of (a) the es sential requirements for the operation of a plant tissue culture lab oratory; (b) the basic procedures of micropropagation, regeneration, and somatic embryogenesis; (c) some specific applications of organ culture systems such as embryo rescue and culture, and anther and microspore culture for haploid and double haploid production; (d) elementary transformation technology; and (e) useful microtechnique and analytical protocols specifically adapted to cultured tissues and cells. The appendices provide a convenient summary of media for mulations and commercial suppliers for the materials described in the text.

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Plant Cell, Tissue and Organ Culture

Several mechanisms in industrial use have significant applications in thermal transportation. The inclusion of hybrid nanoparticles in different mixtures has been studied extensively by researchers due to their wide applications. This report discusses the flow of Powell–Eyring fluid mixed with hybrid nanoparticles over a melting parabolic stretched surface. Flow rheology expressions have been derived under boundary layer theory. Afterwards, similarity transformation has been applied to convert PDEs into associated ODEs. These transformed ODEs have been solved the using finite element procedure (FEP) in the symbolic computational package MAPLE 18.0. The applicability and effectiveness of FEM are presented by addressing grid independent analysis. The reliability of FEM is presented by computing the surface drag force and heat transportation coefficient. The used methodology is highly effective and it can be easily implemented in MAPLE 18.0 for other highly nonlinear problems. It is observed that the thermal profile varies directly with the magnetic parameter, and the opposite trend is recorded for the Prandtl number.

Enhancement in Thermal Energy and Solute Particles Using Hybrid Nanoparticles by Engaging Activation Energy and Chemical Reaction over a Parabolic Surface via Finite Element Approach

The present study examines the impact of unsteady viscous flow in a squeezing channel. Silver–gold hybrid nanofluid particles with different shapes are inserted in the base fluid engine oil. Flow and heat transfer mechanism is detected in the presence of magnetohydrodynamics between the two parallel infinite plates. The thermal conductivity models, that is, Yamada–Ota and Hamilton–Crosser models are used to investigate various shapes (Blade, platelet, cylinder, and brick) of hybrid nanoparticles. The model is made up of paired high nonlinear partial differential equations that are then transformed into ordinary differential equations which are coupled and strong nonlinear using the boundary layer approximation. The MATLAB solver bvp4c package is used to solve the numerical solution of this coupled system. The influence of different parameters on the physical quantities is addressed via graphs. A comparison with already reported results is given in order to confirm the current findings. The analysis shows that surprisingly the Yamada–Ota model of the Hybrid nanofluid gains high temperature and velocity profile than the Hamilton–Crosser model of the hybrid nanofluid. Also, both the models show increasing trends toward increasing the volume fraction rate of silver‐gold hybrid nanoparticles. It is also inferred that the hybrid‐nanoparticles performance is far better than the common nanofluids.

Model‐based comparative study of magnetohydrodynamics unsteady hybrid nanofluid flow between two infinite parallel plates with particle shape effects

Comparative analysis on non-linear radiative heat transfer on MHD Casson nanofluid past a thin needle

Slippage impacton peristaltic transport of MHD hybrid nanofluids (TiO2–Cu/H2O) in an asymmetric channel is addressed. Impact of viscous dissipation and Hall current are analyzed in the modeling as well. Constitutive expressions for viscoelastic Jeffery fluid are employed. The mathematical expressions of the problem are transformed into a set of ordinary differential equations by employing appropriate quantities. Well-known long wavelength assumption is invoked. The obtained dimensionless model is then numerically solved with the help of Adams–Bashforth method. The effects of sundry parameters on flow distributions are demonstrated via plots.

Investigation on TiO2–Cu/H2O hybrid nanofluid with slip conditions in MHD peristaltic flow of Jeffrey material

A rapid propagation and acclimatization response of two different varieties of sugarcane (CP 77,400 and BL-4) was obtained in this study. The shoot apical meristem of different sizes was cultured on MS medium supplemented with different concentrations and combinations of BAP and kinetin either alone or in combination with each other or GA3. Best shoot formation response in CP 77,400 was obtained on MS medium containing 1.5mg/l BAP while in BL-4 the combination of 0.5 mg/l BAP with 0.25 mg/l Kinetin showed best shoot formation response from apical meristem. Meristem of 3.0 mm size proved to be the best size for micropropagation of sugarcane. Excellent multiplication response of In vitro formed shoots was obtained when the concentration of BAP was decreased to 1.0 mg/l in CP 77, 400 and 0.25 mg/l BAP & Kin in BL-4 (i.e. 0.25 mg/lBAP + 0.25 mg/l Kinetin. MS medium containing 1.0 mg/l NAA and 2.0 mg/l IBA showed 100% rooting response of In vitro regenerated shoots of both the varieties of sugarcane within eight days of inoculation. Best hardening response was obtained in Sand+ Soil + Peat (1:1:1) after three week of transplantation in glass house.

An efficient protocol for large scale production of sugarcane through micropropagation

This paper explores the influence of entropy production on MHD hybrid nanofluid (Al2O3–Cu/H2O) flow due to permeable stretching sheet with variable heat flux in the existence of electric field. The partial differential equations are converted into ordinary differential equations by using appropriate transformations. The obtained dimensionless model is then numerically solved with the help of Adams–Bashforth method. The velocity, temperature and entropy generation are obtained under the influence of various emerging quantities examined. It is concluded that existence of magnetic field and suction decelerates the motion of fluid, whereas it magnifies for greater values of an electric field which tends to resolve sticky effects. Furthermore, friction factor and heat transfer rate have been evaluated through tables and bar charts. Under some specific conditions, the present results are matched with the available results to check the accuracy and validity of the present study and we have observed a good agreement with it.

Entropy generation in electrical magnetohydrodynamic flow of Al 2 O 3 –Cu/H 2 O hybrid nanofluid with non-uniform heat flux

The present research work involves shoot formation, their multiplication and rooting in carnation Dianthus caryophyllous. For shoot formation both apical and nodal meristems were used. MS medium containing BAP alone or in combination with kinetin was tested. Best shoot formation response was obtained after 6 days of inoculation from apical meristem and after 7 days of inoculation from nodal meristem on MS medium supplemented with 4.0 mg/l BAP. Apical meristem showed more pronounced effect for shoot formation than nodal meristem. Well-developed shoots were shifted for their multiplication. Maximum number of multiple shoots were obtained on MS medium containing 1.0 mg/l BAP. These multiple shoots increased in their number when were given subsequent incubation period. Addition of Kinetin to BAP failed to show good shoot multiplication response. Shoots after attaining the size of 5.0 cm were shifted for rooting. Best rooting response was obtained on MS medium containing 1.0 mg/l NAA. Well rooted plants were shifted into glass house for hardening and acclimatization and were shifted to natural climatic conditions.

An efficient protocol for in vitro propagation of carnation (dianthus caryophyllus)

Present theoretical investigation is a mathematical illustration of an application to endoscopy by incorporating hybrid nanoparticles and an induced magnetic field with a rheological fluid model for more realistic results. Rheological fluid behavior is characterized by the Ostwald-de-Waele power-law model. A hybrid nanofluid mechanism is considered comprising platelet-shaped nanoparticles since nanoparticles are potential drug transportation tools in biomedical applications. Moreover, ciliary activity is encountered regarding their extensive applications in performing complex functions along with buoyancy effects. An endoscope is inserted inside a ciliated tube and peristalsis occurred due to ciliary activity in the gap between tube and endoscope. A non-Newtonian model is developed by mathematical formulation which is tackled analytically using homotopy analysis. The outcomes are interpreted graphically along with the pressure rise and streamlining configuration for the case of negligible inertial forces and long wavelength. A three-dimensional graphical interpretation of axial velocity is studied as well. Moreover, tables are prepared and displayed for a more physical insight.

https://www.mdpi.com/2079-6412/10/2/186/pdf

Aamir Ali

Papers

Investigation on TiO2–Cu/H2O hybrid nanofluid with slip conditions in MHD peristaltic flow of Jeffrey material

An efficient protocol for large scale production of sugarcane through micropropagation

Entropy generation in electrical magnetohydrodynamic flow of Al 2 O 3 –Cu/H 2 O hybrid nanofluid with non-uniform heat flux

An efficient protocol for in vitro propagation of carnation (dianthus caryophyllus)

MHD Effects on Ciliary-Induced Peristaltic Flow Coatings with Rheological Hybrid Nanofluid