Synthesis and characterization of PLA nanocomposites containing nanosilica modified with different organosilanes I. Effect of the organosilanes on the properties of nanocomposites: Macromolecular,morphological, and rheologic characterization

Polylactide nanocomposites containing different loadings of nanosilica were prepared by employing bulk ring opening polymerization from lactide. Nanosilica was used as such and after surface treatment with different amounts of two distinct silanes. The effects on the properties of the material were evaluated comparing the samples containing organosilane‐modified nanosilica with poly(lactic acid) (PLA) containing unmodified nanosilica. A standard linear PLA and an industrial “film grade” PLA (PLA Natureworks 4032D) were used as reference. Pure silica tends to decrease the molecular weight of the material, deactivating the catalytic system but when silanes are present on the surface, molecular weights are similar to the ones of standard and industrial PLA. Transmission electron microscopy analysis shows that silanes improve the dispersion of the mineral, while rheologic curves suggest that when silanes are present melt viscosity increases markedly at zero shear and decreases faster as the shear rate increases. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Vitrified and nonvitrified municipal solid wastes as ordinary Portland cement (OPC) and sand substitution in mortars

This work aims to evaluate the potential suitability of nonvitrified and vitrified bottom ashes to serve as substitute materials for both OPC and sand in mortars on an industrial scale. Three bottom ashes were selected as OPC substitutes: one was vitrified inside the incinerator plant (W1-C), one was carbonated under ambient conditions for 3 months (W2-C), and part of the carbonated bottom ash was further washed with Ca(OH)2 (W2-W-C). Composition and phases of the bottom ash sources were assessed by XRF and XRD, respectively. Thereafter, mortars were prepared by replacing 10, 20 or 30 wt% of OPC with these bottom ashes. It was shown that even though Ca(OH)₂ washing step (W2-W-C) led to an increment of the compressive strength in final mortars compared to the use of W2-C, it failed to reach the mechanical performance of OPC. On the contrary, the use of vitrified bottom ashes (W1-C) could lead to obtaining compressive strength comparable to that of standard mortar if added up to 10 wt%. Regarding the sand substitution, vitrified bottom ashes could reach suitable compressive strength when replacing 20 wt% of standard sand. The alkali aggregate reaction test confirmed the neutrality of substitution material added up to 50 wt%.     

A neuro‐fuzzy computational approach for multicriteria optimisation of the quality of espresso coffee by pod based on the extraction time,temperature and blend

We demonstrate how soft computing methods can be exploited to solve multicriteria quality optimisation problems in food science and technology. In particular, we link neuro‐fuzzy modelling techniques with simulated annealing to optimise/design the quality of espresso coffee by pod. The design variables are the extraction time (ranging from 10 to 30 s), temperature (80–110 °C) and blends (100% Arabica, 100% Robusta and Arabica Robusta: A20R80, A80R20 and A40R60); they are not the only variables that affect the sensory profile of a cup of espresso coffee, but have a strong impact on the sensory quality of the beverage. Based on the framework, we show that the particular problem is a nonlinear one. Hence, an espresso coffee characterised by a specific sensory profile can be extracted using different sets of parameter values. For example, the same sensory profile can be obtained using either pure Robusta extracted at 22 s and 94 °C or 90% Arabica and 10% Robusta extracted at 25 s and 99 °C. Yet, the global optimum with respect to the distance to the optimum sensorial values is obtained using 70% Arabica and 30% Robusta extracted at 15 s around 93 °C.     

The File Mover: high‐performance data transfer for the grid

The exploration in many scientific disciplines (e.g. High‐Energy Physics, Climate Modeling, and Life Sciences) involves the production and the analysis of massive data collections, whose archival, retrieval, and analysis require the coordinated usage of high‐capacity computing, network, and storage resources. To obtain satisfactory performance, these applications require the availability of a high‐performance, reliable data transfer mechanisms, able to minimize the data transfer time that often dominates their execution time. In this paper we present the File Mover, an efficient data transfer system specifically tailored to the needs of data‐intensive applications, that exploits the overlay networks paradigm to provide superior performance with respect to conventional file transfer systems. An extensive experimental evaluation, carried out by means of a proof‐of‐concept implementation of the File Mover for a variety of network scenarios, shows the ability of the File Mover to outperform alternative data transfer systems. Copyright © 2007 John Wiley & Sons, Ltd.     

单级功率因数校正LED驱动器

引言新的能源之星LED驱动器法规要求家用产品的功率因数(PF)达到0.7或更高,要求商用产品的功率因数(PF)达到0.9。本文将介绍一款适用于LED驱动器的极     

An experimental study on the conditions of safe oxidation of toluene with oxygen—carbon dioxide mixtures

The flammability limits of saturated vapours of toluene in oxygen—carbon dioxide mixtures have been measured up to 180°C and 10 atm using a directThe flammability data have been presented in a pressure versus temperature diagram. The convenience of this form of diagram to determine the conditions     

On the thermal decomposition of acrylic copolymer/ nitric acid liquors

The hazards of the ASAHI process for the wet-spinning of an acrylic copolymer (90% by weight polyacrylonitrile and 10% by weight methylacrylate) by watThe experimental program has been performed using a Sikarex-3 adiabatic calorimeter, for initial temperatures up to 50°C and acrylic copolymer concenThe experiments have shown that, at the highest PAN concentrations, self-heating of the liquors occurs even when starting from ambient temperature, proA two step reaction mechanism has been tentatively proposed. During the first step, reactive intermediates are formed through a slightly exothermic rea     

Flammability limits of saturated vapors: Toluene-oxygen-carbon dioxide mixtures

The flammability limits of saturated toluene-oxygen-carbon dioxide mixtures have been evaluated using a new experimental technique, the experiments beiThe good agreement obtained with the data available in the literature shows the effectiveness of this new technique, which proves also to be simpler, c     

On the flammability limits of saturated vapours of hydrocarbons

The upper flammability limits of saturated vapours of four hydrocarbons (cyclohexane, benzene, toluene and ethylbenzene) in oxygen—nitrogen and oxygeThe different reactivity of the four hydrocarbons is discussed, taking into account the pressure dependence of the flammability limits, which appeared