Release characteristics of polyphenols from microencapsulated Terminalia arjuna extract: Effects of simulated gastric fluid

Terminalia arjuna (TA) encapsulated microcapsules were prepared using two different wall materials consisting of a combination of maltodextrin + gelatine (MDG) and maltodextrin + gum acacia (MDGA). Total phenolic, tannin, and flavonoids content of TA ethanolic extract were found to be 19.6 ± 0.7 g/100 g extract, 7.5 ± 0.7 g/100 g extract, and 2.7 ± 0.2 g/100 g extract, respectively. In vitro release of polyphenols increased with the time of stirring in simulated intestinal fluid (SIF; pH 6.8). The encapsulation efficiency (EE) and release of polyphenols (after 60 min) were observed to be 42 ± 4.g/100 g; 77.0 g/100 g; and 31.0 ± 0.5 g/100 g; 72.0 g/100 g, respectively for MDGA and MDG microcapsules. This study concluded that MDGA provided higher EE and stability than MDG for TA extract.     

Purity and morphology of aluminium films

A continuous wire feed source of aluminium of 99.999% purity in conjunction with a composite ceramic boat has been used to deposit aluminium films of high purity in vacuum. The impurity content was analysed by proton-induced X-ray analysis with a Van de Graaff accelerator, supplemented by X-ray fluorescence, optical emission and Auger electron spectroscopy. The low impurity content achieved ( 50 atomic ppm) is attributed to the small quantity of molten aluminium maintained in the boat at one time.

The morphology of the Al films was studied by reflection electron diffraction, X-ray diffraction and scanning electron microscopy. Thick Al films grew with {111} and {311} texture orientations. The grain size variation with thickness generally followed the known variation with the deposition rate.     

Improving grinding performance by controlling air flow around a grinding wheel

In grinding, high specific heat is generated, and hence, appropriate control of temperature through effective flow of grinding fluid is necessary to obtain a quality ground surface. It is known that in conventional fluid delivery method, most of fluid is wasted due to presence of a stiff air layer around the grinding wheel. This air layer is generated around the wheel due to the rotation of the porous grinding wheel at a high speed. To improve grinding performance, hence, penetration into this air layer is required.In this work, a pneumatic barrier set-up has been developed for controlling the stiff air layer around the grinding wheel. The formation of stiff air layer has been studied experimentally by measuring the variation of air pressure around grinding wheel periphery at different parametric conditions of pneumatic barrier. This pneumatic barrier tends to break the stiff air layer before the fluid flow area or grinding zone. A remarkable amount of reduction in pressure of the air layer is observed at the fluid flow zone. To observe beneficial effects of suppressing the air layer, grinding experiments are performed under dry, flood cooling and flood cooling with pneumatic barrier setup. Reduction of grinding forces and surface roughness are clearly observed with the use of pneumatic barrier setup, and hence, its applicability.     

Vibration damping characteristics of carbon nanotubes-based thin hybrid composite spherical shell structures

The present work deals with the evaluation of elastic properties and dynamic analyses of thin hybrid composite shell structures, which consist of conventional carbon fiber as the reinforcing phase and multiwalled carbon nanotubes-based polymer as the matrix phase. The Mori-Tanaka and strength of material method has been implemented to determine the elastic properties of such hybrid composite structures without and with considering agglomerations. An eight-noded shell element, which considers stress resultant-type Koiter's shell theory and transverse shear effect as per Mindlin's hypothesis having five degrees of freedom at each node, has been utilized for discretizing and analysis of such hybrid shell structures. The Rayleigh damping model has been implemented in order to study the effect of carbon nanotubes (CNTs) on damping capacity of such hybrid composite shell structures. Different types of spherical shell panels have been analyzed in order to study the time and frequency responses. Results show that the elastic properties as well as damping properties of such hybrid composite structures improved with the addition of CNTs as compared to conventional carbon fiber reinforced composites laminates; effects of some important parameters on the vibration characteristic of such hybrid composite shell structures have also been presented. The effects of agglomeration parameters on the elastic properties and their influences on the dynamic responses considering different layers and stacking sequences have also been investigated.     

Toward On‐and‐Off Magnetism: Reversible Electrochemistry to Control Magnetic Phase Transitions in Spinel Ferrites

The magnetoelectric effect, i.e., electric‐field control of magnetism in artificial heterostructures is usually limited to surface/interface atoms of the magnetic materials. In order to attain electrical control of magnetism in bulk ferromagnets, this study proposes to extend the definition of magnetoelectric phenomena to include reversible, chemistry‐controlled magnetization switching. A large and reversible change in the room temperature magnetization in strong ferromagnets is reported, with electrochemistry‐driven Li‐ion exchange; carefully chosen spinel ferrites demonstrate a reversible magnetization variation up to 50% for CuFe₂O₄ and 70% for ZnFe₂O₄. In case of CuFe₂O₄, the magnetization variation is predominantly associated with the preferential reduction of Cu²⁺ to Cu⁺ ions, and, hence, abides a nearly one‐to‐one relationship with the amount of injected Li‐ions. In addition, the reduction of Cu²⁺ also annihilates the Fe³⁺? O? Cu²⁺ magnetic interaction, resulting in a marked decrease in the Neél temperature of CuFe₂O₄. In contrast, the electrical tuning of superexchange interactions is found to play the decisive role in ZnFe₂O₄, where the simple electrochemical reduction model of magnetic cations can only explain a nominal fraction of the total magnetization variation, and indeed an electrochemically controlled reversible change in transition temperature is found necessary to account for the large magnetization variation observed.     

PILOTING PEN-BASED COMPUTERS

Organizations using pilot projects to determine if pen-based technology is appropriate for their user and organizational needs were interviewed for this article. Their acceptance of pen-based computers, technology assessment techniques, and implementation experiences are discussed. The article concludes with recommendations for IS managers who plan to adopt pen-based systems, with steps to ensure support for this new technology.     

Antioxidant potential of herbs and spices during deep frying of ghee

The present study was carried out to evaluate antioxidant potential of ashwagandha, clove, coriander, green tea, shatavari and vidarikand extracts as compared to BHA. Clove, coriander and green tea extracts showed significantly higher antioxidant activity than vidarikand, shatavari and ashwagandha extracts. Radical‐scavenging activity by DPPH model system revealed that clove and green tea extracts were superior to other extracts. All the natural antioxidants significantly reduced the formation of peroxides, FFA, thiobarbituric acid value and conjugated dienes. Ghee with added clove, green tea and coriander extracts showed higher induction period as compared to ghee containing vidarikand, ashwagandha, shatavari or BHA.     

Recent advances in optimization and game theoretic control for networked systems

The aim of this paper is to provide an overview, although unnecessarily complete, of recent advances in optimal control, optimization, and game theory for networked systems. First, the recent research results and progress in optimal control and game theory for logical domain networked systems are summarized. Then, the recent developments on networked optimization and game theory for continuous domain systems are presented afterward. Finally, after introducing some recent practical applications of optimal control and game theory on networked systems, we conclude the paper with a short discussion on future research perspectives.     

AN OBJECT-ORIENTED VIEW Productivity Comparison with Structured Development

Object-oriented methodologies may be conceptually superior to structured development, but new technology adoption and usage costs often hinder an organization's migration to this new development approach. This article focuses on some specific situations in which migration to an OO methodology becomes an attractive choice for an organization that is looking to improve software quality and productivity.     

Effect of organized anionic surfactant system on the kinetics of V(V)-organic substrate-initiated polymerization of acrylonitrile

The kinetics of polymerization of acyrlonitrile (AN) initiated by a V(V)-cyclohexanone redox system in the presence of a surfactant was studied over a temperature range of 30–50°C in acidic medium. The anionic surfactant sodium dodecyl sulfate (SDS) enhances the rate of polymerization (R_p) as well as rate of V(V) consumption (−R_v). The cationic surfactant, cetyltrimethylammonium bromide (CTAB), decreases both R_p and −R_v, while the nonionic surfactant, Triton-X-100, has no effect on the rate. The change of concentration of the surfactant, monomer, acid, and cosolvent on the rate of polymerization were examined. Both R_p and −R_v are computed in the presence of different organic substrates, i.e., cyclohexanone, cyclopentanone, glycerol, and citric acid. The viscosity-average molecular weight (M_v) of the polycrylonitrile, obtained at different [SDS], was determined using the Mark-Howink relationship. A suitable mechanistic scheme was proposed for the process. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 1825–1833, 1997