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Ignition Point (ignition + point)
Selected AbstractsFlammability ranking of foliage species by factor analysis of physical and chemical pyric propertiesFIRE AND MATERIALS, Issue 6 2008Yanlong Shan Abstract In this paper, factor analysis is introduced to evaluate the flammability of 55 foliage species that may be used in China for construction of the fuel break network of forest strips with lower flammability. Six pyric parameters, i.e. air dry moisture content, absolute dry moisture content, ignition point, ash content, caloric value and extractive content, are measured and used as variables for factor analysis. The covariance analysis shows that four principal factors can be extracted to reflect the flammability in different physical and chemical senses. In terms of the contributions of the four factors to the variances and the physical significance of the relevant parameters, the four factors are, respectively, termed as ,flaming factor,' ,air dry factor,' ,ash factor' and ,absolute dry factor.' The stability of the factor analysis method is examined by a different number of samples considered, and the variation degrees of the orderings indicate that the method has high reliability to measure the total flammability of foliage species. The results of the flammability evaluation are verified by comparison with the recommended tree species in the Chinese technology standard. Copyright © 2008 John Wiley & Sons, Ltd. [source] Note on the determination of the ignition point in forest fires propagation using a control algorithmINTERNATIONAL JOURNAL FOR NUMERICAL METHODS IN BIOMEDICAL ENGINEERING, Issue 11 2008M. Bergmann Abstract This paper is devoted to the determination of the origin point in forest fires propagation using a control algorithm. The forest fires propagation are mathematically modelled starting from a reaction diffusion model. A volume of fluid (V.O.F.) formulation is also used to determine the fraction of the area which is burnt. After having developed the objective functional and its derivative, results from an optimization process based on the simplex method is presented. It is shown that the ignition point and the final time of the fire propagation are precisely recovered, even for a realistic, non-horizontal, terrain. Copyright © 2007 John Wiley & Sons, Ltd. [source] Preparation and characterization of microcapsulated red phosphorus and its flame-retardant mechanism in halogen-free flame retardant polyolefinsPOLYMER INTERNATIONAL, Issue 8 2003Qiang Wu Abstract Microcapsulated red phosphorus (MRP), with a melamine,formaldehyde resin coating layer, was prepared by two-step coating processes. The physical and chemical properties of MRP were characterized by Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and transmission electron microscopy (TEM) and other measurements. The flame retardant action and mechanism of MRP in the halogen-free flame retardant (HFFR) polyolefins (PO) blends have been studied using cone calorimeter, limiting oxygen index (LOI), thermogravimetric analysis (TGA) and dynamic FTIR spectroscopy. The results show that the MRP, which is coated with melamine,formaldehyde resin, has a higher ignition point, a considerably lower amount of phosphine evolution and of water absorption compared with red phosphorus (RP) itself. The data observed by cone calorimeter, LOI and TGA measurements from the PO/HFFR blends demonstrated that the MRP can decrease the heat release rate and effective heat of combustion, and increase the thermostability and LOI values of PO materials. The dynamic FTIR results revealed the flame-retardant mechanism that RP can promote the formation of charred layers with the P,O and P,C complexes in the condensed phase during burning of polymer materials. Copyright © 2003 Society of Chemical Industry [source] Homogeneous TiB2 Ceramics Achieved by Electric Current-Assisted Self-Propagating Reaction SinteringJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 10 2007David Salamon Using spark plasma sintering techniques, homogeneous microstructures of titanium diboride (TiB2) ceramics were obtained by sintering of boron and titanium powder mixtures. The results show that an additional electric current is essential for achieving a large number of evenly distributed ignition points that ensure that the self-propagating reaction simultaneously takes place within the entire volume. The effects of the electric current, the use of Mg additions, and the heating rates on the resulting TiB2 ceramic densities and microstructures are discussed. [source] | |||||||||||||