预测FTIR光谱中烟气毒性组分体积分数的定量模型

分析烟气中毒性组分FTIR图谱的定量方法很多，鉴于每种方法都有其独特的优缺点，着重介绍了经典最小二乘法(CLS)和偏最小二乘法(PLS)。     

Leading fire signatures of spacecraft materials: Light gases, condensables, and particulates

The primary goal of this research is to provide recommendations for the eventual development of more effective and efficient fire sensors to be installed in space vehicles and habitats. An entirely new ground-based testing facility that generated fire signatures was developed to perform the combustion and pyrolysis experiments of eight different practical spacecraft materials. The flaming and smoldering of polymers approved by the National Aeronautics and Space Administration (NASA) generate three types of residues: condensables, light gases, and particulates. The residues were characterized by gas chromatography (GC), Fourier transform infrared (FTIR) spectroscopy, and transmission electron microscopy (TEM). The analysis was interpreted as a function of oxygen concentration, temperature, and flow direction. Key findings are that the combustion of some materials such as Kevlar and cotton can only be identified by light gases, while the combustion of other materials, such as silicone and melamine, is best detected using a particulate-specific sensor. The implications during a fire event, its suppression, astronaut health in post-event cleanup as well as material recommendations are briefly discussed.     

A comparative study of As(III) and As(V) in aqueous solutions and adsorbed on iron oxy-hydroxides by Raman spectroscopy

The sorption of the arsenite (AsO₃³⁻) and the arsenate (AsO₄³⁻) ions and their conjugate acids onto iron oxides is one of main processes controlling the distribution of arsenic in the environment. The present work intends to provide a large vibrational spectroscopic database for comparison of As(III) and As(V) speciation in aqueous solutions and at the iron oxide - solution interface. With this purpose, ferrihydrite, feroxyhyte, goethite and hematite were firstly synthesized, characterized in detail and used for adsorption experiments. Raman spectra were recorded from As(III) and As(V) aqueous solutions at various pH conditions selected in order to highlight arsenic speciation. Raman Scattering and Diffuse Reflectance Infrared Fourier Transform (DRIFT) studies were carried out to examine the respective As-bonding mechanisms. The collected data were curve-fitted and discussed according to molecular symmetry concepts. X-ray Absorption Near Edge Spectroscopy (XANES) was applied to confirm the oxidation state of the sorbed species. The comprehensive spectroscopic investigation contributes to a better understanding of arsenic complexation by iron oxides.     

Experimental study of water hammer-induced forces and deformations in dry pipe fire protection systems

When designing a fire protection system, every effort should be taken to ensure its maximum operational safety. Therefore, correct identification of the dynamic load affecting the system during water hammer occurrence is essential to increase the operational reliability of such fire protection systems on their design stage. A test stand with a simple deluge system was designed for the experiments. The layout consisted of a distribution duct and one straight branch line (including three different diameter values) equipped with three fire nozzles. However, the main objective of this study is not to study the water hammer itself but, rather, to study the forces and displacements induced by the water hammer. The measurement results will be used to calibrate a mathematical model created using MATLAB software. The verified model will in turn enable numerical determination of the dynamic force values for larger systems. Furthermore, these force values will allow for pinpointing the critical sections, for which it is necessary to prevent displacements or transfer the acting forces to the building structure.     

Combining engineering and data-driven approaches: Development of a generic fire risk model facilitating calibration

Fire risk models support decision making for engineering problems under the consistent consideration of the associated uncertainties. Empirical approaches can be used for cost-benefit studies when enough data about the decision problem are available. But often the empirical approaches are not detailed enough. Engineering risk models, on the other hand, may be detailed but typically involve assumptions that may result in a biased risk assessment and make a cost-benefit study problematic. In two related papers it is shown how engineering and data-driven modeling can be combined by developing a generic risk model that is calibrated to observed fire loss data. Generic risk models assess the risk of buildings based on specific risk indicators and support risk assessment at a portfolio level. After an introduction to the principles of generic risk assessment, the focus of the present paper is on the development of a generic fire risk model for single family houses as an example. The risk model considers the building characteristics of a single family house as well as the uncertainties associated with the fire spread in a building and the intervention of the fire brigade.     

Quantifying life safety Part II: Quantification of fire protection systems

In part I of the paper, an assembly building was analyzed in order to compute the failure probabilities, and thus the safety level, of current code-compliant buildings. In this second part, various fire protection systems are modeled within the fire and egress simulations in order to quantify their magnitude of impact. Since all fire protection systems can fail to perform as designed on demand, the potential failure along with its probability is accounted for in an event tree analysis. Comparing the resulting failure probabilities of the performance-based analyses with and without fire protection systems yields information about the magnitude of impact of the fire protection systems on the level of safety and hence allows a direct, objective, and quantitative comparison to other systems and designs. Accounting for the cost of the systems, a direct cost–benefit analysis can be conducted.     

Experimental study of the effects of a thermal plume entrainment mode on the flow structure: Application to fire

The aim of this work is to experimentally simulate two heat sources of fire, one placed at ground level, the other at a height above the ground, in order to determine the effect of source air entrainment on the resulting flow structure. The development of a free thermal plume was examined by generating a plume produced from an electrically heated disk at a constant temperature. We first studied the behavior of a thermal plume induced by a disk embedded in a horizontal plate placed at the level of the ground. This configuration ensured a regular lateral entrainment of air to the plume. The analysis of the average fields as well as the axial evolution of velocity and temperature showed an important widening of the profiles that encouraged a faster spread of the plume. We then determined the structure of the thermal plume generated by the same source placed at a height above the ground, ensuring simultaneous vertical and lateral entrainment of air into the resulting plume.     

Aerial firefighting against urban fire: Mock-up house experiments of fire suppression by helicopters

The Great Hanshin Earthquake in 1995 claimed approximately 6400 lives. The majority was killed in large fires after the earthquake. Roads were cut off and collapsed buildings blocked the access of fire engines to fire fields. Water mains were broken and lack of water prevented firefighting efforts. If aerial firefighting had been effectively applied, many lives could have been saved.     

Fire risk perception and building evacuation by vulnerable persons: Points of view of laypersons,fire victims and experts

Fire risk perception and its influence on building evacuation were studied in order to improve building evacuation processes. The sample adopted in this study consisted of (i) laypersons, mostly elderly; (ii) healthcare professionals working with vulnerable individuals who live with disability on an everyday basis, for their point of view on disabled persons; (iii) fire victims for their experience (persons who suffered burns in a fire).Qualitative research was used to study fire risk perception and to understand the attitudes and behaviours of individuals. The information was collected during interviews following a questionnaire that combined questions of a general nature, questions referring to the fire and questions focused on the experience of evacuating a building.Results of this inductive, exploratory and qualitative method showed differences between the analysis of experts, the point of view of laypersons and the experience of fire victims. They also showed that risk perception is influenced by psychological, social, physical, political (here regulatory and normative) and cultural factors. Fire risk perception is based on the individual-environment-risk paradigm. Among the factors characterising risk perception, we noted the preponderant role of trust emerges, as well as that of the human environments (daily and emergency), the physical environment (building) and the climate of safety in which the event takes place. These different dimensions of fire risk perception show that it is a combination of psychometric and cultural paradigms. Building evacuation is seen as a psychological process involving both emotion and cognition.The resulting model aims to improve the understanding of a building evacuation process and to provide tools to anticipate crises.