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In this study, polystyrene composites (PS–GOf) with variable concentration (0.5; 1; 2; 3; 4; and 5 wt%) of GOfwere obtained through the in-situpolymerisation of the styrene in the presence of benzoyl peroxide and graphene oxide(GO) functionalized with 3-(methacryloyloxy)-propyltrimethoxysilane(γ-MPTS). For determining the morphological and structural particularities of polymeric composites transmission electron microscopy (TEM) measurements were performed. The influence of functionalized GO on thermal and combustion properties of polystyrene (PS)-based composite materials was determined through several methods: Thermogravimetry (TGA); derived thermogravimetry (DTG); microscale combustion calorimetry analysis (MCC); and chemical kinetic studies through TGA and MCC determinations at similar heating rates.

New fire-resistant thermosets are prepared based on a bisphenol A-epoxy resin which is thermally crosslinked in the presence of dicyandiamide and two phenols containing phosphorus atoms. The thermosets are characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, thermogravimetric analysis (TGA), and microscale combustion calorimetry (MCC) tests. A nonisothermal kinetic study is performed based on processing of TGA data applying the method proposed by Vyazovkin. The lifetime prediction analyses establish that the phosphorus-containing polymers could be used at a constant temperature of 200°C up to 200–780 min. The MCC tests reveal an improvement of the flammability behavior, as well as a significant heat release capacity reduction for phosphorus-containing samples compared to the sample which has no phosphorus component.

AbstractAcknowledging the importance of the bioeconomy as an important dimension of sustainable economic development, and particularly for E.U. strategies, this paper aims to identify and assess several bioeconomy modellers under the compelling effects of education and research–development–innovation activities. Within this frame of reference, the authors have assessed the role of intellectual capital in shaping bioeconomy outcomes, distinct for the new E.U.-13 and E.U.-15. A complex set of methods and macro-econometric models was applied on two balanced panels, compiled during 1995–2016, that bind random effects models with panel-corrected standard errors, spatial analysis and structural equation modelling. Overall, the importance of research, development, innovation and specific skills acquired in the field of bioeconomy is outlined, as key elements of E.U. economic strategies, being essential for all Member States.

Understanding fire behaviour indicators is very important, especially taking into account their integration in the primary fire evaluation process as part of the dynamic and continuous evaluation of risks to which people are exposed to. Construction fires are always characterised by certain critical behaviour factors such as smoke, air currents, heat and flames. Classical training methods for firefighters are practical exercises that are expensive and risky. The aim of the present article is to briefly present a new training method consisting of a dynamic 3D system based on immersive virtual reality. This paper presents results based on the characteristics and thermal values of the flashover in a case study. The phenomenon are simulated by using the Fire Dynamics Simulator, a computer program developed on a complex mathematical apparatus that can generate multiple output data (indicators such as temperatures, gas concentrations, speeds etc.). Results are validated by experimental tests in a testing metal facility from the Police Academy “A. I. Cuza”, Bucharest. The 3D graphic results offered by the simulation highlights the conditions and parameters to which the firefighters involved in putting-out a fire, in the presented training scenario, would be exposed.

Nowadays the world is facing an increasingly traffic, especially in the road. In order to short the distances and cross various road areas, road tunnels are built frequently and longest as possible. One of the greatest emergency situations that can occur in road tunnels, is represented by fire, involving all conditions relating to the nature and density of combustible materials existing, smoke, toxic gases and the combustion debris from fire fighting and action in order to minimize the negative consequences of it. Also, road tunnels represent semi-closed and closed spaces, with high fire risk, so no easy fire safety management opportunities can be used. Road tunnels can be framed in the category above mentioned, being exposed to a high traffic, because most of them are 20-30 years old and were built for the traffic estimated of those times. A simulation using Pyrosim software is based on the physical model in which one electrical fault accident involving a car appear. The accident, consisting in a fire event at one stationary car, is modeled at 1.5 m height. Considering an electrical fault followed by a fire, temperature and smoke spreading depending on time in this tunnel were obtained. Also, sprinklers have been used in the simulation time, in order to give an accurate firefighting simulation. There were obtained important values which allow us to realize an appropriate impact on the event in aim of minimizing the time for a promptly intervention and to limit the damages.

This paper tackles the physicochemical characterization of spent coffee grounds resulting from a blend of six types of coffee (Arabica and Robusta) used in different proportions in a professional DeLonghi coffee machine. Information was collected on their particle size distribution, morphological characteristics, composition and energy value. Since it is impossible to make pellets and briquettes out of pure spent coffee grounds that would meet sustainability standards, our paper suggests another use for coffee grounds as firelighters. Several firelighters containing agricultural waste, additives and 100% Arabica spent coffee grounds have been designed and manufactured. The firelighters thus obtained were first analyzed by microscale combustion calorimetry (MCC), a standard test method used to determine the flammability characteristics of materials. The firelighters obtained have high values of heat release capacity, and of the total flow of heat released, as well. The firelight containing coffee grounds also has a lower percentage of residue and a longer duration of the combustion process, which are important aspects considering the practical applications concerned.

Flame retardation of poly (vinyl alcohol) with oligophosphonates, either as singular flame retardant filler or in the presence of intumescent additives, is a key to achieving eco-friendly advanced composites with improved reaction-to-fire properties. Herein, following a facile synthetic approach, PVA/oligophosphonate/ammonium sulfate composites were prepared via casting method. It was demonstrated that a low content of phosphorus led to composites exhibiting improved flame retardant properties. The peak heat release rate was substantially reduced in all the cases, depending on the content of oligophosphonates-based flame retardants or ammonium sulfate intumescent additive. Thermogravimetric data showed that the incorporation of the flame retardant significantly increased the phosphorus-rich char yield at elevated temperature.

The purpose of this research: The large-scale use of the external cladding systems with polystyrene thermal insulation, for rehabilitation of existing and new buildings, requires the experimental determination of the fire performance of these thermal insulating systems, both as wholes, and from the materials point of view, which they are constituted from. This study aims to present the evaluation of the fire performance of some polystyrene thermosystems and of the elements that make up these systems. Methodology: Experimental tests are carried out related to the fire behavior of polystyrene thermal insulation systems used in building renovation, in order to determine the mechanisms of flames initiation and propagation on the surface of combustible facades under natural ventilation conditions, the behavior of thermosystems in different fires scenarios and determining the fire performance of the constituent elements of these thermosystems. As a result of the performed tests, it was found that the overall performance of the thermal system against the fire action during the testing was mainly influenced by the value of the thermal load density parameter, and by the way the thermosystem is built and put into operation. The contribution of the components of the thermal system to the ignition, burning, development and propagation of flames and smoke differed on a case-by-case basis, depending on the materials used to cover the polystyrene, and the time elapsed, since they were put into operation. In the direct fire area of the fire test, temperatures above 1000 deg C have been recorded that have led, in some cases, to complete damage to the thermosystem. It is intended to establish a concordance between the parameters resulting from the tests on the facades of buildings, and those measured during the fire reaction tests of the elements which the facades were made from. This highlights the need to introduce the requirement of performing fire performance tests for building facade systems, following a harmonized testing methodology across the European Union.