Emotion regulation and decision making under risk and uncertainty.

It is well established that emotion plays a key role in human social and economic decision making. The recent literature on emotion regulation (ER), however, highlights that humans typically make efforts to control emotion experiences. This leaves open the possibility that decision effects previously attributed to acute emotion may be a consequence of acute ER strategies such as cognitive reappraisal and expressive suppression. In Study 1, we manipulated ER of laboratory-induced fear and disgust, and found that the cognitive reappraisal of these negative emotions promotes risky decisions (reduces risk aversion) in the Balloon Analogue Risk Task and is associated with increased performance in the prehunch/hunch period of the Iowa Gambling Task. In Study 2, we found that naturally occurring negative emotions also increase risk aversion in Balloon Analogue Risk Task, but the incidental use of cognitive reappraisal of emotions impedes this effect. We offer evidence that the increased effectiveness of cognitive reappraisal in reducing the experience of emotions underlies its beneficial effects on decision making. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Drug absorption and release properties of crosslinked hydrogels based on diepoxy-terminated poly(ethylene glycol)s and aliphatic polyamines — a study on the effect of the gel molecular structure

Crosslinked hydrogels with well-defined chemical structures and characteristics were prepared through the reaction between diepoxy-terminated poly(ethylene glycol)s of various molecular weights and aliphatic polyamines of different hydrocarbon chain length and functionalities, and the influence of some network parameters (molecular weight between crosslinking points, crosslinking degree, hydrophobic character) upon the absorption and release of drugs of different capacity to interact with the polymer chains was comparatively investigated. Diclofenac sodium (DCFNa) and 5-fluorouracil (5FU) were used as model drugs, based on their dissimilar hydrophobic character and ability of DCFNa to form crown ether-like complexes with PEG chains through the sodium cation. The experiments showed that the most important interactions occurring in these systems were mainly the hydrophobic ones and to a lesser extent the complexation of the Na⁺ ion by the PEG chains. Both of them were in favor of DCFNa, resulting in a larger incorporation and a slower release of this one in comparison with 5FU. For both drugs, loading was larger for hydrogels with shorter PEG chains and/or crosslinked with amines with longer hydrocarbon chain or higher functionality. Drug release tests showed a lower rate for stronger drug–network interactions in agreement with the absorption experiments.     

Thermoelastic Deformations of Cylindrical Multi-Layered Shells Using a Direct Approach

In this article we study the deformation of thermo-elastic multi-layered shells, using a Cosserat model. By this direct approach, the shell-like bodies are modeled as deformable surfaces with a triad of rigidly rotating directors assigned to every point. The thermal effects are described with the help of two independent temperature fields. Concerning cylindrical orthotropic layered shells, we establish a general solution procedure for a class of thermal stresses problems. These analytical solutions are compared in some special cases with the corresponding three-dimensional solutions and thus, the thermo-elastic coupling coefficients for shells are identified in terms of the material/geometrical parameters of the layers. Finally, we present a comparison between our theoretical results and the numerical solutions obtained by a finite element analysis of a 3-layered cylindrical shell.     

应用GT-Styrene~苯乙烯回收技术对裂解汽油的改质分析

通过采用GT-Styrene苯乙烯回收技术对传统的裂解汽油处理工艺进行改进,汽油的产品性能可以得到有效的改善,并回收有价值的苯乙烯产品和得到高质量的混合二甲苯产品。     

Interphase of polyoctenamer-single-wall carbon nanotubes by thermogravimetric analysis in air

Non-isothermal thermogravimetric analysis in air, of polyoctenamer-single wall carbon nanotubes (PO-SWNTs), loaded by various amounts of SWNTs up to 10% wt., at different heating rates (ranging from 5 to 40°C/min) is reported. The thermal degradation in the air of PO_SWNTs is dominated by a main single sigmoidal dependence, assigned to the polymer and eventually polymer-nanofiller interphase, over which a weaker sigmoid assigned to the thermo-oxidative degradation of the nanofiller is superimposed at higher temperatures. The temperature at which the nanocomposite's residual mass fraction reaches x% wt. of the initial mass, T_x%, is reported (for x = 5, 50, and 85). The dependence of T_x% on the heating rate and the loading by nanotubes is analyzed. The temperature derivative of the thermograms defines new parameters (inflection residual mass fraction and inflection temperature) and (degradation) width. Their dependence on the loading by SWNTs was reported. Estimation of the interphase in polymer-based nanocomposites is based on the postulate that the dependence of the inflection temperature on the composition of the nanocomposite obeys a Fox-like dependence, where the bulk polymer and the polymer trapped within the interphase are considered as a blend of two miscible polymers. Complementary Raman, x-ray diffraction, and differential scanning calorimetry support these results.     

Rheological Aspects of Spanish Honeys

The purpose of this work was to investigate the rheological behavior of Spanish honeys under different conditions (at different temperatures and concentrations). All the samples were characterized to determine their physicochemical (moisture, ⁰Brix, pH, ash, conductivity, color, total acidity, diastase activity, 5-hydroxymethylfurfural content, sugar content) and thermal (glass transition temperature) profiles. The honeys samples (80.4–82 ⁰Brix) behaved as Newtonian fluid; as expected, their viscosity increased with the solid content and decreased with the temperature. Two experimental viscosity models (Arrhenius and Vogel–Taumman–Fulcher) were checked using the experimental data to correlate the influence of temperature on honey viscosity. A simplified model was proposed to describe the combined effect of the temperatures and concentrations (⁰Brix) on the viscosity of Spanish honeys. The dynamic viscosity and complex viscosity had the same magnitude at 40 °C, 45 °C, and 50 °C for of all the samples and the Cox Merz rule could be applied at these temperatures.     

Moth‐eye antireflection coating fabricated by nanoimprint lithography on 1 eV dilute nitride solar cell

We report on the performance of biomimicked antireflection coating applied to dilute nitride solar cell. The coating consists of nanostructures replicating the moth‐eye geometry and has been fabricated by nanoimprint lithography directly within the window layer covering the dilute nitride absorbing junction. The mean reflectivity within the spectral range of 320–1800 nm remains under 5% for incident angles up to 45°. The effect of the coating on the cell performance was assessed by measuring the current–voltage characteristics under simulated solar illumination. A clear performance increase was identified when comparing a solar cell with the moth‐eye coating with a solar cell having a standard SiN_x/SiO₂ coating. Copyright © 2012 John Wiley & Sons, Ltd.     

Rheological Properties of Honey from Burkina Faso: Loss Modulus and Complex Viscosity Modeling

This study evaluated the rheological behavior of Burkina Faso honey and the use of exponential and polynomial models to predict the influence of chemical composition and temperature on the viscoelastic parameters: complex viscosity (η*) and loss modulus (G’’). Samples were first characterized by evaluating: water activity, 5-hydroxy methyl furfural, sugars (fructose, glucose, and sucrose), electrical conductivity, moisture, and color. Dynamic rheological properties were obtained at different temperatures (5, 10, 15, 20, 25, 30, and 40°C). All the honeys displayed Newtonian behavior. Complex viscosity and loss modulus can be predicted based on the chemical composition and temperature using polynomial models (R² > 98.00%).     

New use of size exclusion chromatography in kinetics of mechanical degradation of polymers in solution

A new method to investigate the mechanical degradation of polymers in solution is described that uses size exclusion chromatograms of the initial polymer and of the degraded sample. The incipient parts of these chromatograms are analyzed to obtain kinetic data about degradation at the level of infinitesimal fractions. The procedure is based on the fact that mechanical degradation of the polymers is a first-order reaction and macromolecules are cleaved mostly in their central region. The rate constant and the variation in the rate constant with molecular weight are determined in a single experiment, avoiding additional fractionation steps. Moreover, the slope of the size exclusion chromatographic calibration curve is derived, opening new ways to determine polydispersities or even to make rapid calibration for unknown polymers. To verify the method, the rate constant and the molecular weight dependence of the rate constant were determined for the sonic degradation of polystyrene in toluene. The rate constant is found to vary with the square of the molecular weight, and its value is in good agreement with results reported using much more laborious methods. © 1993 John Wiley & Sons, Inc.