Investigation of metal absorption and antibacterial activity on cotton fabric modified by low temperature plasma

In this work, the silver particle absorption and antibacterial activity of cotton fabric when modified by low temperature plasma were investigated. The modification consisted of plasma pre-functionalization followed by one-step wet treatment with silver nitrate solution. Oxygen and nitrogen were used as the working gases in the system, and the results were compared. The results showed that nitrogen plasma-treated samples can absorb more silver particles than oxygen-treated samples, and thus the antibacterial activity of the samples in this case, which was analyzed by the counting bacteria test, was increased considerably.     

Study of trace elements in milk by nuclear analytical techniques

This work is part of a project with the IAEA, in a coordinated program on Trace Elements in Human and Bio-Environmental Systems to evaluate their nutritional requirements, interrelations and the role of trace elements in health, metabolism, etc. Cow's milk being regarded as one of the most important and nutritious foodstuffs consumed by people. Hence as a first step, an elemental analysis for milk was carried out for this purpose; a few samples of pasteurized milk and local sample were investigated for essential and toxic trace elements. The secondary aim of this project was the assessment of various analytical techniques involved. However, in the present work, the methods involved were AAS, PIXE and NAA. The latter method was applied both instrumentally and radiochemically. Although the results pertaining to the various methods employed are not in good agreement. there is, however, some justification to clarify this internal inconsistency. The precision of NAA and AAS allows a greater degree of acceptance. Although PIXE is very fast and rather routine, the technique for trace element analysis needs certain adaptations and development.     

Green and mild laccase-catalyzed aerobic oxidative coupling of benzenediol derivatives with various sodium benzenesulfinates

The oxidative coupling reaction between hydroquinone or catechols and various sodium benzenesulfinates was investigated using the laccase from Trametes versicolor, in the presence of O₂ in a phosphate buffer solution at room temperature to afford sulfonyl benzenediols in 75–95% yield.     

Reversed-phase dispersive liquid-liquid microextraction with central composite design optimization for preconcentration and HPLC determination of oleuropein

A reversed-phase dispersive liquid-liquid microextraction (RP-DLLME) method was developed for the preconcentration and direct HPLC determination of oleuropein in olive's processing wastewater (OPW) and olive leaves extracts. In conventional DLLME, the sedimented phase is a micro-drop of a chlorinated organic solvent that is not compatible with RP-HPLC. Therefore, solvent evaporation and reconstitution with an appropriate solvent is often required. In RP-DLLME, this problem was overcome by overturning the solvent polarity in the ordinary DLLME and replacing the organic solvent with water. A central composite chemometrics design was used for multivariate optimization of the effects of five different parameters influencing the extraction efficiency of the method. In the optimized conditions, a mixture of 1.4 mL of an ethyl acetate extract of sample and 40 μL water (pH 5.0) was rapidly injected into 5.3 mL of cyclohexane. After centrifugation of the formed cloudy mixture, a micro-drop of the aqueous phase was sedimented at the conical bottom of the centrifuge tube. This phase, that contained the preconcentrated and partially purified analyte, was directly injected into an RP-HPLC column for analysis. A mean extraction recovery of 102.5 (±4.5) % with enrichment factors exceeding 38, was obtained for five replicated analysis. The detection limit of the method (3σ) for OE was 0.02 μg L⁻¹ for OPW and 2 × 10⁻³ mg kg⁻¹ for olive leaves samples. The results showed that, RP-DLLME is a promising technique which is quick, easily operated and can be directly coupled to HPLC.     

The effect of an axial external magnetic field on the output power of a small-bore CuBr laser

In this work, the effect of an axial external moveable magnetic field on the output power of a CuBr laser with small-bore tube has been investigated. In all experiments, by applying an EMF along the tube axis, the laser output power has been decreased and by moving the EMF toward the cathode region, more substantial decrease of output power has been observed. The effect is more significant at a magnetic field intensity of 1100 G, Ne gas pressure of 35 Torr, frequency of 19 kHz and voltage of 3.8 kV, such that there was no laser emission when the EMF was placed around the cathode.     

Inventory control and pricing for perishable products under age and price dependent stochastic demand

Multistage stochastic programming (SP) with both endogenous and exogenous uncertainties is a novel problem in which some uncertain parameters are decision-dependent and others are independent of decisions. The main difficulty of this problem is that nonanticipativity constraints (NACs) make up a significantly large constraint set, growing very fast with the number of scenarios and leading to an intractable model. Usually, a lot of these constraints are redundant and hence, identification and elimination of redundant NACs can cause a significant reduction in the problem size. Recently, a polynomial time algorithm has been proposed in the literature which is able to identify all redundant NACs in an SP problem with only endogenous uncertainty. In this paper, however, we extend the algorithm proposed in the literature and present a new method which is able to make the upper most possible reduction in the number of NACs in any SP with both exogenous and endogenous uncertain parameters. Proving the validity of this method is another innovation of this study. Computational results confirm that the proposed approach can significantly reduce the problem size within a reasonable computation time.     

A tetra-coordinate nickel(II) complex as neutral carrier for nitrate-selective PVC membrane electrode

The potentiometric response properties and applications of a tetra-coordinate nickel(II) complex with relatively high selectivity toward nitrate ion are described. The nickel(II) complex of 5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradeca-4,6,11,13-tetraene was used as a neutral carrier into plasticized poly(vinyl chloride) (PVC) membrane. The influence of several variables was investigated in order to optimize the potentiometric response and selectivity of the electrode. The resulting membrane electrode incorporating 31.0% PVC, 61.0% dioctyl phthalate (DOP) as plasticizer, 3% methyltrioctylammonium chloride (MTOAC) as a cationic additive and 5% carrier (all w/w) demonstrates a Nernstian response slope of −59.6 mV per decade over the concentration range of 5×10⁻⁶-1×10⁻¹ M NO₃⁻. The electrode exhibits a fast response time (≤10 s), a detection limit of 2.5×10⁻⁶ M, and can be used over a wide pH range of 4-12. The electrode shows improved selectivity in comparison to most of the previously reported nitrate-selective electrodes. It was successfully applied to the determination of nitrate ion in natural water samples.     

Superdense Coding with Uniformly Accelerated Particle

We study superdense coding with uniformly accelerated particle in single mode approximation and beyond single mode approximation. We use four different functions, the capacity of superdense coding, negativity, discord and the probability of success for evaluating the final results. In single mode approximation, all the four functions behave as expected, however in beyond single mode approximation, except the probability of success, the other three functions represent peculiar behaviors at least for special ranges where the beyond single mode approximation is strong.     

Large deflection of flexible tapered functionally graded beam

In this paper the semi-analytical analyses of the flexible cantilever tapered functionally graded beam under combined inclined end loading and intermediate loading are studied.In order to derive the fully non-linear equations governing the non-linear deformation,a curvilinear coordinate system is introduced.A general non-linear second order differential equation that governs the shape of a deflected beam is derived based on the geometric nonlinearities,infinitesimal local displacements and local rotation concepts with remarkable physical properties of functionally graded materials.The solutions obtained from semi-analytical methods are numerically compared with the existing elliptic integral solution for the case of a flexible uniform cantilever functionally graded beam.The effects of taper ratio,inclined end load angle and material property gradient on large deflection of the beam are evaluated.The Adomian decomposition method will be useful toward the design of tapered functionally graded compliant mechanisms driven by smart actuators.     

Dimeric ortho‐palladated homoveratrylamine as an efficient homogeneous catalyst for copper‐free Sonogashira cross‐coupling reaction

The catalytic activity of ortho‐palladated [Pd{C6H2(CH2CH2NH2)‐(OMe)2,3,4}(m‐Br)]2, a complex of homoveratrylamine in the copper‐free Sonogashira coupling reaction has been investigated. This complex is a catalyst that is efficient, stable and non‐sensitive to air and moisture in the Sonogashira reaction. In this homogeneous catalytic system, various aryl halides were efficiently coupled with phenylacetylene in mostly moderate to good yields in N‐methylpyrrolidone at 100 °C under copper‐free conditions. Copyright © 2012 John Wiley & Sons, Ltd.