Highly collective atomic transport mechanism in high-entropy glass-forming metallic liquids

Quasielastic neutron scattering(QENS) has been used to study the atomic relaxation process and microscopic transport mechanism in high-entropy glass-forming metallic(HE-GFM) liquids. Self-intermediate scattering functions obtained from the QENS data show unusually large stretching, which indicates highly heterogeneous atomic dynamics in HE-GFM liquids. In these liquids, a group of atoms over a length scale of about 21 ? diffuses collectively even well above the melting temperature. However, the temperature dependence of diffusion process in one of the HE-GFM liquid is Arrhenius, but in the other HE-GFM liquid it is non-Arrhenius. Although the glass-forming ability of these HE-GFM liquids is very poor, the diffusion coefficients obtained from the QENS data indicate the long range atomic transport process is much slower than that of the best metallic glass-forming liquids at their melting temperatures.     

Evaluation of power extraction circuits on piezo‐transducers operating under low‐frequency vibration‐induced strains in bridges

The concept of piezoelectric energy harvesting (PEH) provides a promising solution for perpetually running low‐power electronic devices such as wireless sensor networks by harvesting ambient vibrations generated from civil structures such as long span bridges, city flyovers, elevated metro corridors, which are constantly under dynamic loads. However, its successful industrial‐scale deployment on civil structures is still not realised because of the low‐frequency of vibrations (typically <5 Hz) encountered there, coupled with the low levels of voltage generation. The vast majority of PEH‐related studies have only focused on PEH configurations and geometries, Often entailing secondary structures. d₃₁ mode, which is the most natural mode of excitation, has not been investigated in depth for piezo‐patches directly bonded on the main structure. Studies, which have focused on electronic conditioning circuitry, have been restricted to typically high‐voltage and high‐frequency scenarios only. This paper focuses on systematically studying the issues inflicting energy harvesting from the ambient vibrations induced flexural strains civil structures, such as city flyovers, using piezo elements in d₃₁ mode. Vibration measurements are first undertaken from a typical city flyover consisting of steel girders supporting a reinforced concrete (RC) deck. The basic site measurements are employed to perform a laboratory‐based parametric study to investigate the influence of parameters such as vibration frequency, voltage, and circuit components like diodes on PEH. On the basis of the experimental results, it can be concluded that power in microwatts range can be typically harvested from these civil structures through directly bonded piezo patches in d₃₁ mode. However, there are still issues associated with electronic circuitry accompanying harvesters, such as diodes and storage elements. The same are summarised and future directions envisioned.     

Design by optimization and comparative evaluation of vesicular gels of etodolac for transdermal delivery

Aim of the present study was to design vesicular gels of etodolac loaded liposomes and ethosomes for effective transdermal delivery. The physicochemical properties of vesicular gels were compared with 45% v/v ethanolic etodolac solution and commercial product (PROXYM®). The liposomes were prepared by film hydration technique whereas ethosomes were prepared by cold method respectively. Both the systems were characterized for various physicochemical properties. The size range of liposomes shows 186?nm–363?nm whereas for ethosomes 170?nm–261?nm respectively. The zeta potential of optimized liposomes and ethosomes was found to be ?36.5?mV and ?48.3?mV, respectively. The highest %EE of liposomes and ethosomes shows 71.5% and 78.5%, respectively. The permeation of liposomes shows in the range of 67.50%–86.06% whereas ethosomes shows 52.30%–99.49%, respectively. The optimization was done by 3² experimental design. The optimized vesicular dispersions were subjected to gel preparation using carbopol 940 NF. The prepared liposomal gel (ETO-LG) and ethosomal gel (ETO-EG) were optimized and characterized. The vesicular gels showed desirable results compared to other test formulations.     

Fabrication and characterization of hybrid nanofibers from poly(vinyl alcohol), milk protein and metal carbonates

Porous three dimensional nanofibrous membranes were fabricated from poly(vinyl alcohol) (PVA), milk protein and inorganic salts such as calcium carbonate (CaCO3) or magnesium carbonate (MgCO3). Microscopic investigations showed that the fibers have smooth morphology with an average diameter of 300-500 nm and a surface area of 5.29 m2g(-1). Thermal analysis of the composite nanofibers showed a decrease in glass transition temperature as compared to PVA nanofiber. Incorporation of CaCO3 and MgCO3 into the nanofiber matrix was confirmed by energy dispersive spectroscopy and X-ray diffraction analysis. The cytocompatibility of electrospun composite nanofiber sheets was evaluated using human lung fibroblasts (IMR-90). There was an increase in cell attachment and cell density on milk protein incorporated to PVA-CaCO3 and PVA-MgCO3 fibers within a week of cell seeding. The cytocompatibility and increase in cell adhesion property of the hybrid nanofiber may provide significant advantages for such materials in biomedical applications.     

Quantitative spectroscopic analysis of heterogeneous mixtures: the correction of multiplicative effects caused by variations in physical properties of samples

Spectral measurements of complex heterogeneous types of mixture samples are often affected by significant multiplicative effects resulting from light scattering, due to physical variations (e.g., particle size and shape, sample packing, and sample surface, etc.) inherent within the individual samples. Therefore, the separation of the spectral contributions due to variations in chemical compositions from those caused by physical variations is crucial to accurate quantitative spectroscopic analysis of heterogeneous samples. In this work, an improved strategy has been proposed to estimate the multiplicative parameters accounting for multiplicative effects in each measured spectrum and, hence, mitigate the detrimental influence of multiplicative effects on the quantitative spectroscopic analysis of heterogeneous samples. The basic assumption of the proposed method is that light scattering due to physical variations has the same effects on the spectral contributions of each of the spectroscopically active chemical components in the same sample mixture. On the basis of this underlying assumption, the proposed method realizes the efficient estimation of the multiplicative parameters by solving a simple quadratic programming problem. The performance of the proposed method has been tested on two publicly available benchmark data sets (i.e., near-infrared total diffuse transmittance spectra of four-component suspension samples and near-infrared spectral data of meat samples) and compared with some empirical approaches designed for the same purpose. It was found that the proposed method provided appreciable improvement in quantitative spectroscopic analysis of heterogeneous mixture samples. The study indicates that accurate quantitative spectroscopic analysis of heterogeneous mixture samples can be achieved through the combination of spectroscopic techniques with smart modeling methodology.     

Hybrid BWM-ELECTRE-based decision framework for effective offshore outsourcing adoption: a case study

The present study seeks to develop a decision framework of enabler to help managers in offshore outsourcing adoption by focusing on the relevant enablers and their intensities. A hybrid Best Worst Method (BWM) – ELimination and Choice Expressing REality approach is used to test the applicability of developed offshore outsourcing focused enabler’s across four automotive business organisations in India and the adoption score of framework among case organisations is evaluated too. The intensity of offshore outsourcing focused enablers is analysed through BWM and the ranking of organisations and adoption index scores are computed through ELimination and Choice Expressing REality method. The developed framework possesses high adoption rate in offshore outsourcing initiatives across the case organisations. Findings of the study reveal that among the main enablers; managerial and strategic enabler holds the highest weight followed by technological enablers and organisational enablers. This study further presents the sensitivity analysis to check the robustness of developed framework by conducting experiments in different conditions. This research work will facilitate managers and professionals involved in practising offshore outscoring initiatives and results in higher cost advantages on labour and raw material, increased economies of scale, and higher sustainable business development.     

Weibull Probability Model for Fracture Strength of Aluminium (1101)-Alumina Particle Reinforced Metal Matrix Composite

In recent times, conventional materials are replaced by metal matrix composites (MMCs) due to their high specific strength and modulus. Strength reliability, one of the key factors restricting wider use of composite materials in various applications, is commonly characterized by Weibull strength distribution function. In the present work, statistical analysis of the strength data of 15% volume alumina particle (mean size 15 μm) reinforced in aluminum alloy (1101 grade alloy) fabricated by stir casting metho...     

High‐Performance Partially Aligned Semiconductive Single‐Walled Carbon Nanotube Transistors Achieved with a Parallel Technique

Single‐walled carbon nanotubes (SWNTs) are widely thought to be a strong contender for next‐generation printed electronic transistor materials. However, large‐scale solution‐based parallel assembly of SWNTs to obtain high‐performance transistor devices is challenging. SWNTs have anisotropic properties and, although partial alignment of the nanotubes has been theoretically predicted to achieve optimum transistor device performance, thus far no parallel solution‐based technique can achieve this. Herein a novel solution‐based technique, the immersion‐cum‐shake method, is reported to achieve partially aligned SWNT networks using semiconductive (99% enriched) SWNTs (s‐SWNTs). By immersing an aminosilane‐treated wafer into a solution of nanotubes placed on a rotary shaker, the repetitive flow of the nanotube solution over the wafer surface during the deposition process orients the nanotubes toward the fluid flow direction. By adjusting the nanotube concentration in the solution, the nanotube density of the partially aligned network can be controlled; linear densities ranging from 5 to 45 SWNTs/μm are observed. Through control of the linear SWNT density and channel length, the optimum SWNT‐based field‐effect transistor devices achieve outstanding performance metrics (with an on/off ratio of ~3.2 × 10⁴ and mobility 46.5 cm²/Vs). Atomic force microscopy shows that the partial alignment is uniform over an area of 20 × 20 mm² and confirms that the orientation of the nanotubes is mostly along the fluid flow direction, with a narrow orientation scatter characterized by a full width at half maximum (FWHM) of <15° for all but the densest film, which is 35°. This parallel process is large‐scale applicable and exploits the anisotropic properties of the SWNTs, presenting a viable path forward for industrial adoption of SWNTs in printed, flexible, and large‐area electronics.     

Ionic Liquids Assisted Synthesis of ZnO Nanostructures:Controlled Size,Morphology and Antibacterial Properties

Systematic analysis about the exploitation of imidazolium based ionic liquids（ILs）,[BMIM]BF₄[IL1],[EMIM]BF₄ [IL2]and[BMIM]PF₆[IL3]as the morphological template on the basic sol-gel method adopted synthesis of nanostructured zinc oxide（ZnO） is presented.X-ray diffraction（XRD）,particle size analysis（PSA） and scanning electron microscopy（SEM） have been employed for the characterization of structure and morphology of the synthesized ZnO particles.Well-defined capsule like shaped morphology with lower nanosize is observed for the ZnO nanoparticles with IL1 than those with IL2 and IL3.This confirms that IL1 served as an effective templating material due to their unique properties.Especially the effective aggregation of ZnO particles with a self-organized frame of IL1 was the essential factor to produce the lower nanosized ZnO with capsule shaped structure.The synthesized ZnO samples with IL2 and IL3 fabricated the flake like shaped and rod like shaped morphologies in the range of nanoscale.The formed ZnO nanoparticles with IL2 exhibit higher nanosize than the ZnO nanoparticles produced by IL1,owing to shorter length of alkyl group in its cation which restricts steric effect and permits the nanoparticles to grow longer.Even though IL3 produced the discrete ZnO nanorods,the hydrophobic nature of IL3 created the higher nanosize than the ZnO nanoparticles formed by other two ionic liquids.Antibacterial properties of the synthesized ZnO nanostructures were investigated against Staphylococcus aureus（gram positive） and Escherichia coli（gram negative） bacteria by Agar diffusion test method.Microbial experiments indicate that the synthesized ZnO samples show a wide spectrum of antimicrobial activities and performed better against S.aureus than E.coli with the same concentration of ZnO.     

Impact of hydrophilic binders on stability of lipid-based sustained release matrices of quetiapine fumarate by the continuous twin screw melt granulation technique

Dose dumping is the major drawback of sustained release (SR) matrices. The current research aimed to develop the stable lipid-based SR matrices of quetiapine fumarate (QTF) using Geleol^TM (glyceryl monostearate; GMS) as the lipid matrix carrier and Klucel^TM EF (HPC EF), Kollidon® VA64, and Kollidon® 12PF as hydrophilic binders. Formulations were developed using advanced twin screw melt granulation (TSMG) approach and the direct compression (DC) technique. Compared with the blends of DC, the granules of TSMG exhibited improved flow properties and tabletability. Solid-state characterization by differential scanning calorimetry of the prepared granules exhibited the crystalline nature of the lipid. Fourier transform infrared spectroscopy demonstrated no interaction between the formulation ingredients. The compressed matrices of TSMG and DC resulted in the sustained release of a drug over 16–24 h. Upon storage under accelerated conditions for 6 months, the matrices of TSMG retained their sustained release characteristics with no dose dumping in alcohol, whereas the matrices of DC resulted in the dose dumping of the drug attributing to the loss of matrix integrity and phase separation of lipid. Thus, it is concluded that the uniform distribution of a softened binder into a molten lipid carrier results in the stable matrices of TSMG.