Junctionless Gate-all-around Nanowire FET with Asymmetric Spacer for Continued Scaling

Silicon - In this paper, we have performed the scaling of asymmetric junctionless (JL) SOI nanowire (NW) FET at 10 nm gate length (LG). To study the device electrical performance various...     

Thermal analysis of buoyancy-motivated Casson fluid flow with time-independent chemical reaction under Lorentz forces

The present research study examines the magneto-hydrodynamic natural convection visco-elastic boundary layer of Casson fluid past a nonlinear stretching sheet with Joule and viscous dissipation effects under the influence of chemical reaction. To differentiate the visco-elastic nature of Casson fluid with Newtonian fluids, an established Casson model is considered. The present physical problem is modeled by utilizing the considered geometry. The resulting system of coupled nonlinear partial differential equations is reduced to a system of nonlinear ordinary differential equations by applying suitable similarity transformations. Numerical solutions of these reduced nondimensional governing flow field equations are obtained by applying the Runge-Kutta integration scheme with the shooting method (RK-4). The physical behavior of different control parameters is described through graphs and tables. The present study describes that the velocity and temperature profiles decreased for increasing values of Casson fluid parameter. Velocity field diminished for the increasing nonlinear parameter whereas velocity profile magnified for increasing free convection parameter. Thermal field enhanced with increasing magnetic parameter in the flow regime. The concentration profile decreased for the rising values of the chemical reaction parameter. The magnitude of the skin-friction coefficient enhanced with increasing magnetic parameter. Increasing Eckert number increases the heat transfer rate and increasing chemical reaction parameter magnifies the mass transfer rate. Finally, the similarity results presented in this article are excellently matched with previously available solutions in the literature.     

Sustainable green synthesis of silver nanoparticles by using Rangoon creeper leaves extract and their spectral analysis and anti‐bacterial studies

The plant‐based biological molecules possess exceptionally controlled assembling properties to make them suitable in the synthesis of metal nanoparticles. In the present study, an efficient simple one‐pot method was employed for the synthesis of silver nanoparticles (SNPs) from the Rangoon creeper (RC) aqueous leaf extract. Biomolecules present in the leaf extract play a significant role as reducing agent as well as capping agent in the formation of RC‐SNPs. The formation of RC‐SNPs was confirmed by using several analytical techniques such as Fourier‐transform infrared spectroscopy and ultraviolet–visible spectrophotometer studies. The presence of a sharp surface plasmon resonance peak at 449 nm showed the formation of RC‐SNPs. X‐ray diffraction analysis showed the crystalline nature of the RC‐SNPs with a face‐centred cubic structure. Elemental analysis of RC‐SNPs was done by using energy‐dispersive X‐ray spectroscopy and X‐ray photoelectron spectroscopy. The morphology of RC‐SNPs was examined by transmission electron microscopy (TEM) in the nano range 12 nm, and thermogravimetric‐differential thermal analysis demonstrated the mechanical strength of RC‐SNPs at various temperatures. The authors’ newly synthesised RC‐SNPs exhibited significant anti‐bacterial activity against Staphylococcus aureus and Escherichia coli. Inspec keywords: silver, nanoparticles, X‐ray photoelectron spectra, antibacterial activity, ultraviolet spectra, microorganisms, X‐ray chemical analysis, differential thermal analysis, X‐ray diffraction, transmission electron microscopy, visible spectra, nanofabrication, surface plasmon resonance, Fourier transform infrared spectra, mechanical strengthOther keywords: silver nanoparticles, ultraviolet–visible spectrophotometry, antibacterial activity, sustainable green synthesis, plant‐based biological molecules, assembling properties, reducing agent, capping agent, Fourier‐transform infrared spectroscopy, surface plasmon resonance, Rangoon creeper aqueous leaf extract, X‐ray diffraction, face‐centred cubic structure, elemental analysis, energy‐dispersive X‐ray spectroscopy, X‐ray photoelectron spectroscopy, transmission electron microscopy, TEM, thermogravimetric‐differential thermal analysis, mechanical strength, Staphylococcus aureus, Escherichia coli, Ag     

Practical alternatives for estimating the failure probabilities of censored life data

For censored life data, Kapur and Lamberson and O'Connor recommend the use of Johnson's formula for non-parametric estimation of the failure distribution, F(t). The formula is used to calculate the adjusted ranks of the recorded failures, which are input into the median rank estimation equation of F(t). It is our experience that Johnson's formula is fairly difficult for the reliability practitioner to understand and implement. Fortunately, an alternative formula has been developed which is much easier to use. It is demonstrated that the calculated adjusted ranks may be used in either the mean rank or median rank equations for the estimation of F(t). The question which we pose is the following: How does the performance of Johnson's estimator compare with that of the more commonly known and understood Kaplan-Meier, or product-limit, estimator?' To answer this question, the Kaplan-Meier procedure is evaluated with respect to its equivalent adjusted rank of recorded failures. The two procedures are determined to be equivalent with respect to adjusted rank criteria. Therefore, it is proved that with Johnson's estimator adapted for use with the mean rank estimator, the two procedures will yield identical estimates of the failure probabilities. Based upon this finding, it is our recommendation thatthe reliability practitioner use the alternative formula for generation of the adjusted ranks, followed by use of either the mean or median rank formula.     

Polyphenol-Rich Beverages Enhance Zinc Uptake and Metallothionein Expression in Caco-2 Cells

ABSTRACT: The effect of red wine (RW), red grape juice (RGJ), green tea (GT), and representative polyphenols on Caco-2 cell ⁶⁵Zn uptake was explored. RW, RGJ, and GT enhanced the uptake of zinc from rice matrix. Fractionation of RW revealed that enhancing activity of zinc uptake was exclusively resided in the polyphenol fraction. Among the polyphenols tested, only tannic acid and quercitin stimulated the uptake of zinc while others did not influence the uptake. In tune with these results, only tannic acid and quercitin competed with zinquin (a zinc selective fluorophore) for zinc in vitro. Although all the polyphenols tested appear to enhance the expression of metallothionein (MT), the induction was higher with tannic acid, quercitin, and RW extract. Furthermore, phytic acid abrogated the tannic acid-induced MT expression. These results suggest that polyphenol-rich beverages, tannic acid, and quercitin bind and stimulate the zinc uptake and MT expression in Caco-2 cells.     

Electric field induced splitting of the preferred orientation in PMN-PT textured ceramics

We have performed studies of the orientation distribution in <001>_C textured, 0.03(Na_1/2Bi_1/2)TiO₃ - 0.97[0.715Pb(Mg_1/3Nb_2/3)TiO₃ - 0.285PbTiO₃] (0.03NBT-0.97[PMN-28.5PT]) ceramics by a pole figure method, comparing the results to those for PMN-PT single crystal and polycrystal samples. The pole figures about the (001) zone are found to have monoclinic, Ma, phase for textured ceramics in the annealed condition and were similar to those for electrically poled single crystals. However, electrical poling of the textured ceramics resulted in a doublet splitting of the orientation distribution about the direction that defined the original grain texturing. Studies of pole figures about other high-symmetry zones also revealed the development of some degree of preferred orientation along the in-plane directions after poling. Our findings demonstrate that E-field induced phase transformation and domain textures superimpose with that of preferred grain orientations, giving rise to a unique texture symmetry for PMN-PT. The texture symmetry changes are driven by minimization of the elastic strain energy, and have an important effect upon the piezoelectric properties.     

Spark plasma sintered Sm(2)Co(17)-FeCo nanocomposite permanent magnets synthesized by high energy ball milling

Nanocomposite Sm(2)Co(17)-5?wt% FeCo magnets were synthesized by high energy ball milling followed by consolidation into bulk shape by the spark plasma sintering technique. The evolution of magnetic properties was systematically investigated in milled powders as well as in spark plasma sintered samples. A high energy product of 10.2?MGOe and the other magnetic properties of M(s) = 107?emu?g(-1), M(r) = 59?emu?g(-1), M(r)/M(s) = 0.55 and H(c) = 6.4?kOe were achieved in a 5?h milled and spark plasma sintered Sm(2)Co(17)-5?wt% FeCo nanocomposite magnet. The spark plasma sintering was carried out at 700?°C for 5?min with a pressure of 70?MPa. The nanocomposite showed a higher Curie temperature of 955?°C for the Sm(2)Co(17) phase in comparison to its bulk Curie temperature for the Sm(2)Co(17) phase (920?°C). This higher Curie temperature can improve the performance of the magnet at higher temperatures.     

Heat transfer from a vertical fin array by laminar natural convection and radiation—A quasi‐3D approach

A quasi‐3D numerical model is developed to study the problem of laminar natural convection and radiation heat transfer from a vertical fin array. An enclosure is formed by two adjacent vertical fins and vertical base in the fin array. Results obtained from this enclosure are used to predict heat transfer rate from a vertical fin array. All the governing equations related to fluid in the enclosure, together with the heat conduction equation in both fins are solved by using the Alternating Direction Implicit (ADI) method for getting the temperatures along the height of the fin and the temperature of the fluid in the enclosure. Separate analysis is carried out to calculate the heat transfer rates from the end fins in the fin array. A numerical study has been carried out for the effect of fin height, fin spacing, fin array base temperature, and fin emissivity on total heat transfer rates and effectiveness of the fin array. The numerical results obtained for an eight‐fin array show good agreement with the available experimental data. Results show that the fin spacing is the most significant parameter and there exists an optimum value for the fin spacing for which the heat transfer rate from the fin array is maximum. Correlations are presented for predicting the total heat transfer rate, average Nusselt number, and effectiveness of the fin array. © 2011 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.20360     

Electrical and magnetic properties of nanocrystalline BiFeO3 prepared by high energy ball milling and microwave sintering

A new synthesis route with high energy ball milling and microwave sintering is used to obtain nanocrystalline BiFeO3 with improved dielectric and magnetic properties. Electrical and magnetic properties are compared with a conventionally sintered microcrystalline BiFeO3. It is found that the dielectric constant is increased more than one order of magnitude, electrical resistivity by six orders of magnitude and remnant polarization value is increased by 4-5 times for nanocrystalline BiFeO3 in comparison to conventionally sintered microcrystalline BiFeO3. Nanocrystalline BiFeO3 is seen to have ferromagnetic behavior whereas microcrystalline BiFeO3 is known to be antiferromagnetic.