Carbon xerogels as electrodes for supercapacitors. The influence of the catalyst concentration on the microstructure and on the electrochemical properties

Carbon xerogels, synthesized through the resorcinol–formaldehyde polycondensation and subsequently dried under subcritical condition, have been studied as electrodes for supercapacitors. In particular, the influence of the catalyst concentration has been investigated by systematically changing the amount of catalyst (Na₂CO₃) utilized to synthesize the xerogels. To clarify the effect of such variable, both the surface properties and the electrochemical behavior of xerogel-based supercapacitors have been examined. From the xerogels characterization, it can be inferred that the amount of catalyst used has a strong influence on the properties of the material. Contrary to what happens with carbon aerogels, the best properties are obtained with the xerogels synthesized with the least amount of catalyst: in this case the highest measured specific capacitance of the supercapacitor cells, which is assembled coupling two symmetric electrodes in series, is 25 F/g, value that corresponds to a single-electrode specific capacitance of 100 F/g. The maximum energy storage capacity in an aqueous electrolyte is 3.1 Wh/kg. Using more concentrated catalyst solutions, the gel microstructure becomes finer, composed of smaller particles and pores, which in turns leads to an increase of the capillary drying stresses and to the collapse of the organic structure. Consequently, the shrinkage of the gels is high and the final carbon xerogels do not posses sufficient surface area and porosity to store a significative amount of energy.     

Proximity to chipboard industries increases the risk of respiratory and irritation symptoms in children: The Viadana study

Emissions related to wood production processes are a recognized health hazard for professionally exposed subjects. The health effects of living close to wood industries are not known, particularly in the pediatric population. We aimed at investigating if living close to chipboard industries is a health hazard for the children in the Viadana district (Northern Italy).In December 2006, all the children (3-14 years) living in the Viadana district, where two big chipboard industries are located, were surveyed through a parental questionnaire (n = 3854). The children were geocoded, and the distance of their houses/schools from the closest wood plant was computed.Independently of sex, age, nationality, residential area, traffic, parents' education, passive/parental smoking, questionnaire compiler and his/her environmental concern, the children living at < 2 km from chipboard industries had a greater prevalence of respiratory (OR = 1.33, 95%CI: 1.11, 1.60), cough/phlegm (OR = 1.43, 95%CI: 1.08, 1.88), nose/throat/mouth (OR = 1.47, 95%CI: 1.23, 1.75), eye (OR = 1.24, 95%CI: 1.04, 1.48) symptoms, school-days lost (OR = 1.24, 95%CI: 1.04, 1.48), and emergency (OR = 2.14, 95%CI: 1.47, 3.11) and hospital (OR = 2.21, 95%CI: 1.17, 4.18) admissions. There was an inverse dose-response relationship between the adverse health outcomes considered and the distance from the plants. The attributable fractions for the children living close to the chipboard industries were substantial, ranging from 13% (eye symptoms) to 27% (cough/phlegm).The present findings suggest that emissions from chipboard industries might have a serious impact on children's health status and should therefore be reduced and closely monitored.     

Phase evolution and thermophysical properties of plasma sprayed thick zirconia coatings after annealing

Yttria partially stabilized zirconia (YSZ) thick thermal barrier coatings were fabricated by Atmospheric Plasma Spraying (APS) and isothermally annealed at 1315 °C for different durations. The phase composition of as-sprayed and heat-treated free-standing coatings was investigated by X-ray Diffraction (XRD) and the Rietveld method was employed for quantitative phase analysis. High-temperature exposure of YSZ coatings produced the partial decomposition of metastable t′ zirconia phase and the corresponding increase in the amount of stable tetragonal t, cubic c and monoclinic m phases with increasing the aging time.     

Densified aligned carbon nanotube films via vapor phase infiltration of carbon

We report a simple way to produce fully densified aligned carbon nanotube (ACNT) films. The simultaneous growth of nanotubes and densification of the ACNT films by carbon infiltration in the interstitial spaces between nanotubes are accomplished in a single step by the combination of the chemical vapor deposition and chemical vapor infiltration processes. Scanning electron microscope analysis and microbalance measurements showed that after infiltration, the diameters of nanotubes and bulk density of the ACNT films are increased by an order of magnitude (and hence the porosity of the ACNT films is decreased). Transmission electron microscope and Raman scattering analysis showed that after densification, the nanotubes are conformally coated by partially graphitized pyrolytic carbon. The compressive modulus of the densified ACNT films could be increased by three orders of magnitude compared to the pristine ACNT films. Electrical properties are also measured for the densified films showing marked differences with the ACNT films. The property enhanced densified ACNT films constitute a new form of carbon-carbon nanocomposites and could find applications as multifunctional nanocomposites.     

Integrating services and tools in an ICT platform to support eco-innovation in SMEs

Small and medium-sized enterprises (SMEs) represent a key vector to introduce and diffuse eco-innovation in the market, because of their relevance to both the environment and the European gross domestic product. As they are often focused on continuous and incremental innovation of their products, the optimization of product eco-innovation paths can be considered a central aspect of their business. All phases of this process (awareness building and training, analysis, product (re)design and communication/certification) need to be supported to overcome the existing barriers, which mainly consist of lack of experience inside SMEs and cost of information, data, and tools. Information and Communication Technologies can play a role to lower some of the barriers, but currently the numerous services and tools available cover only specific aspects of the whole process, and are often too complex for their direct use by SMEs. The multilingual web-based platform Ecosmes.net here presented aims to integrate user-friendly and free-of-charge services and tools to support all phases of the product eco-innovation process in SMEs. The approach behind mainly consists in developing tailored, simplified tools, and in carrying out ??homogeneous product group?? studies, as a basis for the production of pre-elaborated information and data to be used with the tools developed. Experience gained in 5?years of applications has confirmed that Ecosmes.net can facilitate the start-up of the product eco-innovation process, but has also shown that not all the potentialities have been fully exploited. Moreover, as the eco-innovation market is not developed enough to allow economic management of these kinds of online services, a public initiative is advocated to face this challenge and support a continuous upgrading. Modes and opportunities are proposed and discussed in the conclusion.     

Enhanced utilisation of nonmarketable fish: physical,nutritional and sensory properties of ‘clean label’ fish burgers

Four ‘clean label’ formulations for fish burgers made with mechanically separated fish meat were characterised in sensory, textural and chemical terms. The formulations differed in the ratios of European sea bass to rainbow trout (50:50 and 30:70) and the ratios of fish to potato flakes (dry matter ratio, DMR: 2.5:1 and 1.5:1). The sensory profile was mainly influenced by DMR. Recipes with the higher DMR were positively correlated with sandy, dry and crusty attributes, salty taste and overall flavour. Soft texture was perceived for recipes with the lower DMR, although no differences in texture were detected by a texturometer. Lowering DMR increased ash and water content and decreased protein content, as expected. The results indicated that 100 g of burger provided more essential fatty acids than the recommended daily intake, irrespective of formulation. In conclusion, multiple factor analysis indicated that the main changes detected and perceived were due to DMR.     

A new design paradigm for the development of custom-fit soft sockets for lower limb prostheses

This paper presents a new 3D design paradigm for the development of specific custom-fit products, such as the soft socket of prostheses for lower limb amputees. It is centered on the digital model of the human body and, contrarily to the traditional process almost manually based, it considers the integration of methods and tools coming from different research and application fields: Reverse Engineering, Medical Imaging, Virtual Prototyping, Physics-based Simulation, and Rapid Prototyping. The paper describes the techniques adopted to acquire and create the digital model of the residual limb, the procedure to generate the socket model, the strategy developed for the functional simulation of the socket-stump interaction and, finally, the realization of the physical prototype. Each design step is described with the related problems and the obtained results. Both trans-tibial and trans-femoral amputees have been considered; however, for now the complete process has been validated for trans-tibial prostheses. Major outcomes of the proposed approach stand in a better quality of the final product, in a shorter involvement of the amputee implying a lower psychological impact, in a limited use of physical prototypes, and in a shorter development time. Moreover, the resulting paradigm answers to the Collaborative Engineering guidelines by optimizing the interaction between different domains and enhancing their contributions in a homogeneous development framework.     

Depressive personality styles, dysphoria, and social comparisons in everyday life.

"Sociotropic" people are supposedly vulnerable to dysphoria after negative interpersonal events, whereas "autonomous" people are supposedly vulnerable to achievement-related failures. The present study examined whether these personality styles are borne out in social comparison processes. For 3 weeks, 27 sociotropic and 35 autonomous undergraduates completed records of their social comparisons. Depressive personality style moderated comparison frequency and the affective consequences of comparisons, especially for dysphoric individuals: Dysphoric respondents were especially likely to make comparisons in domains that were congruent with their personalities, and comparisons in congruent domains were associated with greater mood change than comparisons in other domains, perhaps especially for dysphoric respondents. These results have implications for the literatures on social comparison and on depressive personality styles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Erythrocytes as a Model for Heavy Metal-Related Vascular Dysfunction: The Protective Effect of Dietary Components

Heavy metals are toxic environmental pollutants associated with severe ecological and human health risks. Among them is mercury (Hg), widespread in air, soil, and water, due to its peculiar geo-biochemical cycle. The clinical consequences of Hg exposure include neurotoxicity and nephrotoxicity. Furthermore, increased risk for cardiovascular diseases is also reported due to a direct effect on cardiovascular tissues, including endothelial cells, recently identified as important targets for the harmful action of heavy metals. In this review, we will discuss the rationale for the potential use of erythrocytes as a surrogate model to study Hg-related toxicity on the cardiovascular system. The toxic effects of Hg on erythrocytes have been amply investigated in the last few years. Among the observed alterations, phosphatidylserine exposure has been proposed as an underlying mechanism responsible for Hg-induced increased proatherogenic and prothrombotic activity of these cells. Furthermore, following Hg-exposure, a decrease in NOS activity has also been reported, with consequent lowering of NO bioavailability, thus impairing endothelial function. An additional mechanism that may induce a decrease in NO availability is the generation of an oxidative microenvironment. Finally, considering that chronic Hg exposure mainly occurs through contaminated foods, the protective effect of dietary components is also discussed.