Robust projective lag synchronization in drive-response dynamical networks via adaptive control

This paper investigates the problem of projective lag synchronization behavior in drive-response dynamical networks (DRDNs) with identical and non-identical nodes. An adaptive control method is designed to achieve projective lag synchronization with fully unknown parameters and unknown bounded disturbances. These parameters were estimated by adaptive laws obtained by Lyapunov stability theory. Furthermore, sufficient conditions for synchronization are derived analytically using the Lyapunov stability theory and adaptive control. In addition, the unknown bounded disturbances are also overcome by the proposed control. Finally, analytical results show that the states of the dynamical network with non-delayed coupling can be asymptotically synchronized onto a desired scaling factor under the designed controller. Simulation results show the effectiveness of the proposed method.     

A validated high-performance thin-layer chromatography method for the determination of two bioactive lignans,phyllanthin and hypophyllanthin,in the seasonal variation study of Phyllanthus amarus

JPC – Journal of Planar Chromatography – Modern TLC - Phyllanthus amarus Schum. & Thonn. belongs to the family Euphorbiaceae, commonly known as “Bhooamalakee” or...     

Production of textile filaments from carboxymethylated cellulosic pulps

Cellulose - Textile filaments were fabricated from a solution obtained from carboxymethylated cellulose dissolved in aqueous NaOH solution, by wet spinning in an acid coagulation bath. Spinning is...     

Amperometric determination of nanomolar mercury(II) by layered double nanocomposite of zinc/aluminium hydroxide-3(4-methoxyphenyl)propionate modified single-walled carbon nanotube paste electrode

Ionics - A mercury(II) sensor was developed by using single-walled carbon nanotube (SWCNT) paste electrode modified with layered double Zn/Al hydroxide-3(4-methoxyphenyl)propionate nanocomposite...     

High Pressure Super-Heated Electrospray Ionization Mass Spectrometry for Sub-Critical Aqueous Solution

The heating of electrospray ion source under atmospheric pressure is limited to the normal boiling point of the solution. The boiling takes place when the vapor pressure of the liquid at a given temperature equals the ambient pressure. By using a high pressure ESI source, which has been developed previously in our laboratory, a stable electrospray ionization of super-heated aqueous solution is performed up to a solution temperature of 180°C. The ion source is pressurized with pure nitrogen to a maximum pressure of 11 atm, and it is coupled to a commercial mass spectrometer via a custom-made ion transport capillary. A booster pump with variable pumping speed is added to the pumping system to regulate the pressure in the first pumping stage at 1?~?1.3 Torr. High pressure mass spectrometry is performed on several peptides and proteins to demonstrate its application in the temperature-controlled thermally induced denaturation and dissociation. Graphical Abstract

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Synthesis of Poly(ϵ-caprolactone) Grafted Poly(2-hydroxyethyl methacrylate) Functionalized Hydroxyapatite by RAFT and ROP

Poly(?-caprolactone) grafted poly(2-hydroxyethyl methacrylate) functionalized hydroxyapatite (HAP@PHEMA-g-PCL) nanocomposites were synthesized by the combination of reversible addition fragmentation chain transfer (RAFT) polymerization and ring-opening polymerization (ROP). The RAFT agent was anchored on the surface of hydroxyapatite nanocrystals (HAPs) through the silane condensation process of 3-chloropropyltrimethoxysilane followed by reaction with potassium xanthogenate. Poly(2-hydroxyethyl methacrylate) (PHEMA) was covalently functionalized on the surface of HAPs by RAFT polymerization. Then, poly(?-caprolactone) (PCL) was grafted on HAPs by ROP based on the hydroxyl groups of PHEMA to afford HAP@PHEMA-g-PCL. The structure and composition of HAP@PHEMA-g-PCL nanocomposites were characterized by FT-IR, XRD, and TGA analyses. The morphology and formation of the polymer encapsulating HAPs were demonstrated from SEM and TEM images, while the ¹H MNR analysis of the cleaved PHEMA-g-PCL confirmed the grafting.     

Thermodynamics and kinetics of NAD+ adsorption on a glassy carbon electrode

Thermodynamics and kinetics of nicotinamide adenine dinucleotide (NAD⁺) adsorption on a glassy carbon (GC) electrode surface was investigated at various electrode potentials and NAD⁺ concentrations using differential capacitance (DC) and attenuated total reflection Fourier transform infrared (ATR-FTIR) techniques. Equilibrium adsorption measurements confirmed that NAD⁺ spontaneously and strongly adsorbs on the GC electrode surface. The affinity of NAD⁺ towards adsorption on the GC electrode surface was found to increase with an increase in electrode potential (charge) to more positive values; the corresponding apparent Gibbs free energy of adsorption was ?32.80?±?0.25, ?35.61?±?0.86, and ?38.02?±?0.40 kJ mol^?1 on negatively, neutral, and positively charged electrode surfaces, respectively. The kinetics of NAD⁺ adsorption is also found to be highly dependent on the electrode surface potential (charge), and it increases with an increase in electrode potential (charge) to positive values. The adsorption process was modeled using a two-step kinetic model, in which the adsorption process involves the formation of two forms of NAD⁺ on the surface: the thermodynamically unstable (NAD⁺ _ads,rev) and stable (NAD⁺ _ads,stable) forms. ATR-FTIR further confirmed that NAD⁺, indeed, adsorbed on the GC electrode surface.     

Chitosan-Modified Carbon Nanotubes-Based Platform for Low-Density Lipoprotein Detection

We have fabricated an immunosensor based on carbon nanotubes and chitosan (CNT-CH) composite for detection of low density lipoprotein (LDL) molecules via electrochemical impedance technique. The CNT-CH composite deposited on indium tin oxide (ITO)-coated glass electrode has been used to covalently interact with anti-apolipoprotein B (antibody: AAB) via a co-entrapment method. The biofunctionalization of AAB on carboxylated CNT-CH surface has been confirmed by Fourier transform infrared spectroscopic and electron microscopic studies. The covalent functionalization of antibody on transducer surface reveals higher stability and reproducibility of the fabricated immunosensor. Electrochemical properties of the AAB/CNT-CH/ITO electrode have been investigated using cyclic voltammetric and impedimetric techniques. The impedimetric response of the AAB/CNT-CH/ITO immunoelectrode shows a high sensitivity of 0.953?Ω/(mg/dL)/cm² in a detection range of 0–120 mg/dL and low detection limit of 12.5 mg/dL with a regression coefficient of 0.996. The observed low value of association constant (0.34 M^–1s^–1) indicates high affinity of AAB/CNT-CH/ITO immunoelectrode towards LDL molecules. This fabricated immunosensor allows quantitative estimation of LDL concentration with distinguishable variation in the impedance signal.     

Preparation of multiwall carbon nanotubes (MWCNTs) stabilised by highly branched hydrocarbon surfactants and dispersed in natural rubber latex nanocomposites

The performance of single-, double- and triple-chain anionic sulphosuccinate surfactants for dispersing multiwall carbon nanotubes (MWNCTs) in natural rubber latex (NR-latex) was studied using a range of techniques, including field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA) and Raman spectroscopy. The conductivities of the nanocomposites were also investigated using four-point probe measurements. Here, MWCNTs were efficiently dispersed in NR-latex with the aid of hyperbranched tri-chain sulphosuccinate anionic surfactants, specifically sodium 1,4-bis(neopentyloxy)-3-(neopentyloxycarbonyl)-1,4-dioxobutane-2-sulphonate (TC14). This paper highlights that TC14 performs much better than that of the commercially available surfactant sodium dodecyl sulphate (SDS), demonstrating how careful consideration of surfactant architecture leads to improved dispersibility of MWCNTs in NR-latex. The results should be of significant interest for improving nanowiring applications suitable for aerospace-based technology.     

Selective cytotoxicity of organotin(IV) compounds with 2,3-dihydroxybenzyldithiocarbazate Schiff bases

Research on Chemical Intermediates - A series of tridentate ONS Schiff bases were synthesised via condensation by reacting 2,3-dihydroxybenzaldehyde with S-2-methylbenzyldithiocarbazate (S2MBDTC)...