A microprocessor based autoscanner for electromigration studies in thin films

Mass transport due to electromigration can be estimated if the diffusion coefficientD and the electromigration effective charge numberZ* are known. Neutron activated tracer scanning method determine the radioactivity at different positions. An automatic scanning system for determining the radioactive concentration profiles developed using a microprocessor is described in this paper. Using the radioactive concentration profiles the electromigration shift is determined. From this shift the electromigration effective charge numberZ* is calculated. The system developed was tested for tin thin films.     

Biosynthesis of TiO2 Nanoparticles Using Edible Mushroom (Pleurotus djamor) Extract: Mosquito Larvicidal,Histopathological, Antibacterial and Anticancer Effect

Journal of Cluster Science - The titanium dioxide nanoparticles (TiO2NPs) were synthesized by the aqueous extract from P. djamor. The UV–Vis spectrum of TiO2NPs showed maximum absorption at...     

RP-HPLC method for simultaneous estimation of lamivudine, tenofovir disoproxil fumarate and efavirenz in tablet formulation

A simple, rapid, and precise reversed-phase high-performance liquid chromatographic method for the simultaneous determination of lamivudine, tenofovir disoproxil fumarate and efavirenz in bulk and tablet dosage form has been developed and validated. Chromatography was performed on a 150 mm × 4.6 mm i.d., 5-μm particle, Phenomenex Luna C₁₈ column with 30: 45: 25 (v/v/v) acetonitrile: methanol: water as mobile phase at a flow rate of 0.5 mL/min. UV detection was done at 258 nm; lamivudine, tenofovir disoproxil fumarate and efavirenz were eluted with retention times of 3.27, 4.58 and 10.90 min, respectively. The method was validated in accordance with ICH guidelines. Validation revealed the method is specific, rapid, accurate, precise, reliable and reproducible. Calibration plots were linear over the concentration ranges 1–6 μg/mL for lamivudine and tenofovir disoproxil fumarate and 2–12 μg/mL for efavirenz. Limits of detection were 0.05, 0.09 and 0.11 μg/mL and limits of quantification were 0.15, 0.28 and 0.34 μg/mL for lamivudine, tenofovir disoproxil fumarate and efavirenz, respectively. The high recovery and low coefficients of variation confirm the suitability of the method for the simultaneous determination of these three drugs in bulk and tablets.     

Langmuir Monolayers from Substituted 5'-Phenyl-m-terphenyl Carboxylic Acids

A series of 5'-phenyl-m-terphenyl carboxylic acid (PTCA) derivatives with methyl, chloro, and fluoro substituents at both side phenyl rings have been synthesized and characterized as Langmuir monolayers at the air/water interface. A comparative analysis, based on the surface pressure and electric surface potential measurements under a variety of experimental conditions, is complemented with BAM images. Copyright 2001 Academic Press.     

Testing the accuracy of employee-reported data: An inexpensive alternative approach to traditional methods

Although Information Technology (IT) solutions improve the collection and validation of operational data, Operations Managers must often rely on self-reported data from workers to make decisions. The problem with this data is that they are subject to intentional manipulation, thus reducing their suitability for decision-making. A method of identifying manipulated data, digital analysis, addresses this problem at low cost. In this paper, we demonstrate how one uses this method in real-world companies to validate self-reported data from line workers. The results of our study suggest that digital analysis estimates the accuracy of employee reported data in operations management, within limited contexts. These findings lead to improved operating performance by providing a tool for practitioners to exclude inaccurate information.     

Novel vibrational resonance in multistable systems

We investigate the role of multistable states on the occurrence of vibrational resonance in a periodic potential system driven by both a low-frequency and a high-frequency periodic force in both underdamped and overdamped limits. In both cases, when the amplitude of the high-frequency force is varied, the response amplitude at the low-frequency exhibits a series of resonance peaks and approaches a limiting value. Using a theoretical approach, we analyse the mechanism of multiresonance in terms of the resonant frequency and the stability of the equilibrium points of the equation of motion of the slow variable. In the overdamped system, the response amplitude is always higher than in the absence of the high-frequency force. However, in the underdamped system, this happens only if the low-frequency is less than 1. In the underdamped system, the response amplitude is maximum when the equilibrium point around which slow oscillations take place is maximally stable and minimum at the transcritical bifurcation. And in the overdamped system, it is maximum at the transcritical bifurcation and minimum when the associated equilibrium point is maximally stable. When the periodicity of the potential is truncated, the system displays only a few resonance peaks.     

SiC Nanostructures Toward Biomedical Applications and Its Future Challenges

The present work reviews current research activities for possible applications of silicon carbide (SiC) nanostructures. The main attention is devoted to emerging biomedical applications which can bring a boon for a healthy society. Highlights toward the widespread of SiC nanostructures in new fields of applications are reviewed and explained. This article surveys some of the recent work using SiC nanostructures in biomedical field, sensing, and energy harvesting including a review on nanostructure biocompatibility research to date.

The review article begins with an overview of the state of art of silicon carbide along with their behavior, properties, and applications of SiC in bulk, thin films, and nanoscale forms, respectively. The multidisciplinary applications of SiC nanostructures are also highlighted. Different applications elaborated are as follows: (1) biomedical/nanomedical applications, (2) nanoelectronics, (3) sensing applications, (4) energy harvesting, and (5) other emerging areas. The possibility for employing SiC nanostructures to be accomplished in upgrading the existing devices is suggested based on their properties. This article is concluded with some challenges for future applications.     

Cellulose acetate nanocomposite ultrafiltration membranes tailored with hydrous manganese dioxide nanoparticles for water treatment applications

Hydrous manganese dioxide (HMO) nanoparticles incorporated cellulose acetate (CA) composite ultrafiltration (UF) membranes are prepared with the aim of improving the water permeation and BSA contaminant removal. The HMO nanoparticles are synthesized from manganese ion and characterized by FT‐IR, XRD, and FESEM. The effect of variation of HMO on CA membranes is probed using FT‐IR, EDAX, contact angle, SEM, and AFM analysis to demonstrate their chemical functionality, hydrophilicity, and morphology. CA/HMO membranes are showing the enhancement in pure water flux (PWF), water uptake, porosity, hydrophilicity, fouling resistance, BSA rejection, and flux recovery ratio (FRR). CA‐1 membrane displayed higher PWF (143.6 Lm²h^?1), BSA rejection (95.9%), irreversible fouling (93.3%), and FRR (93.3%). Overall results confirmed that the CA/HMO nanocomposite UF membranes overcome the bottlenecks and shows potential for water treatment applications.     

CONDENSATION OF SOME AROMATIC ALDEHYDES WITH DIMETHYL SULFONE

Abstract

Condensation of some aromatic aldehydes with dimethyl sulfone using sodium amide has been studied. Majority of the aldehydes afforded cis-2,6-diaryl-1,4-oxathian-4,4-dioxides as the exclusive product. 4-Methoxybenzaldehyde, in addition, provided the bis α,β-unsaturated sulfone as the major product while 4-nitrobenzaldehyde yielded only the Tischenko product by self-condensation. The products have been characterised by elemental analysis and spectral data.