X-ray CT in the detection of palm weevils

Early detection of the red palm weevils (RPW) is a major challenge in agriculture among all kinds of palm trees due to the nature of the insect and the difficulty to trace them through their life stages associated with the tree life. Many methods have been applied for the weevil detection such as X-ray diffraction techniques, fluoroscopy and ultrasound. On the other hand, the idea of tomography has been used for other purposes such as the determination of the age of the tree and for applied environmental studies. Such technology can also reveal the weevil in principle. In this study, we explore the use of X-ray CT for weevil detection with the Monte Carlo method. A model of the stem of a palm tree is developed for simulations. MCNPX is chosen to carry out the simulations for the radiography tally in the code. The tally records the 2D data of the X-ray beams irradiating the tree model. An iterative reconstruction method for cone beam CT is applied to obtain the 3D slices of the tree model. We are exploring the minimum number of projection angles and the detectability of the weevil. We shall also report the sensitivity of weevil detection using X-ray CT with a large set of simulations with different weevil sizes and tree diameters.     

Eigenvalues of a statistical mechanics matrix

We consider the problem of finding the spectrum of an n × n matrix which arises in the study of a certain model of long-range interactions in a one-dimensional statistical mechanics system. Our analysis exhibits a curious resemblance of the suitably normalized distribution of eigenvalues to the Marčenko–Pastur law in the limit n → ∞.     

Strongly orthogonal geminals: size-extensive and variational reference states

Properties and some applications of strongly orthogonal geminals (APSG) are reviewed emphasizing the motivations for their use and their shortcomings. An overview presents some techniques capable of improving the APSG function.     

Cyclopalladated ferrocenylimine as an efficient catalyst for the syntheses of diarylmethane derivatives

The cyclopalladated ferrocenylimine adducts Ia , Ib , Ic were evaluated in the Suzuki cross‐coupling reaction of benzyl halides with arylboronic acids. The tricyclohexylphosphine adduct Ia exhibited highly catalytic activity for the coupling of aryl and heteroaryl boronic acids containing various functional groups with benzylic bromides and chlorides (up to 99% yield), furnishing diarylmethane derivatives with low catalyst loading (1 mol%). It is worth noting that catalyst Ia can be reused eight times without losing its catalytic activity. Copyright © 2012 John Wiley & Sons, Ltd.     

Solubility of methane in octane + ethanol at temperatures from 303.15 K to 333.15 K and pressures up to 12.01 MPa

Solubility of methane in octane + ethanol was measured at temperatures ranging from 303.15 K to 333.15 K and pressures ranging from 2.60 MPa to 12.01 MPa. Experimental data were analyzed using the Soave-Redlich-Kwong equation of state with three types of mixing rules, and the estimated average deviation from the experimental solubility data was less than 3.5 %.     

Design of polyglycidol-containing microspheres for biomedical applications

The paper presents a short review on the synthesis, characterisation and selected medical applications of poly(styrene/α-tert-butoxy-ω-vinylbenzyl-polyglycidol) (P(S/PGL)) microspheres. The soap-free emulsion-polymerisation of styrene and α-tert-butoxy-ω-vinylbenzyl-polyglycidol macromonomer (PGL) in water yielded core-shell microspheres with a low particle-diameter dispersity (ratio of the weight average particle diameter and the number average particle diameter). The interfacial fraction of PGL units, estimated by XPS, was in the range of 0–42 mole % depending on the concentration of the macromonomer in the polymerisation feed. The studies of adsorption of model proteins showed that the surface fraction of adsorbed protein was significantly reduced when the PGL interfacial fraction was higher than 40 mole %. The P(S/PGL) particles with covalently immobilised proteins were used for the preparation of photonic crystal assemblies suitable for applications in optical biosensors and the medical diagnostic test for the detection of Helicobacter pylori antibodies in the blood serum.     

The preparation and adsorption properties of electrospun aramid nanofibers

The focus of this work is the preparation of aramid nanofibers via electrospinning technology and the study of their adsorption properties. In this article, aramid nanofibers were prepared by electrospinning aramid fibers solution with the addition of lithium chloride (LiCl). It showed a good adsorption capacity when methylene blue (MB) was used as the model target. There were much larger adsorption amounts and faster kinetics of uptaking target species of electrospun aramid nanofibers to MB than that of electrospun polyethersulfone (PES) nanofibers. Compared with activated carbon, aramid nanofibers also have a much faster adsorption rate to MB. Aramid nanofibers were subsequently used to effectively remove endocrine disruptors such as bisphenol A (BPA), phenol (Phe), and p‐hydroquinone (BPhe) from their aqueous solutions. Additionally, molecule imprinted technology enhances aramid nanofibers with much higher adsorption amounts and special adsorption property for endocrine disruptors. These results showed that aramid nanofibers have the potential to be used in environmental applications. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012     

Synthesis and properties of new biotin compounds containing hexyltriethylene glycol chain

The synthesis of a new halogenide containing hexyltriethylene glycol chain functionalized with biotin is reported. The general possibility of this linker to use as the building block for biotinylated compounds syntheses is demonstrated. Two biotinylated esters with different properties for useful surface modification and as fluorescence probes for proteins marking were synthesized. The properties of mentioned compounds were investigated by using surface plazmon resonance ellypsometry and fluorescence spectroscopy.     

Soret and Dufour Effects on Double-Diffusive Free Convection Over a Vertical Truncated Cone in Porous Media with Variable Wall Heat and Mass Fluxes

This work studies the Soret and Dufour effects on the double-diffusive free convection over a downward-pointing vertical truncated cone with variable wall heat and mass fluxes in fluid-saturated porous media. A coordinate transformation is used to derive the nondimensional boundary-layer governing equations, and the obtained nonsimilar equations are then solved by the cubic spline collocation method. Results for local surface temperature and the local surface concentration are presented as functions of Soret parameters, Dufour parameters, power-law exponents, buoyancy ratios, and Lewis numbers. Results show that increasing the Dufour parameter tends to increase the local surface temperature, while it tends to decrease the local surface concentration. An increase in the Soret number leads to a decrease in the local surface temperature for buoyancy assisting flows, while it leads to an increase in the local surface temperature for buoyancy opposing flows. Increasing the Soret number tends to increase the local surface concentration. Moreover, the local surface temperature and the local surface concentration of the truncated cones with higher power-law exponents are lower than those with lower exponents.