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1.
Sci Prog ; 104(3_suppl): 368504221086707, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35322743

RESUMO

This study recycling the industrial byproducts of furnace slag and fly ash to produce slag/ash based zeolite. A scanning electron microscopic/energy dispersive X-ray spectroscopic (SEM/EDS) analysis of this zeolite indicates a high SiO2 content of 53.94%, an Al2O3 content of 23.20%, a silicon-to-aluminum ratio of 2.049, a density of 2.88 g/cm3, and a water content of 0.13% while the zeolite appears as a porous crystalline structure. Results of weighing experiments revealed effective adsorption of liquid salad oil and highly volatile organic solvents after reusing the zeolite up to 6 times. When an adsorbed liquid pollutant was desorbed and the heating temperature exceeded 170 °C and 350 °C, the samples exhibited two exothermic reactions, respectively, the mean maximum enthalpy were 0.427 and 0.461 mW, and the mean per gram of accumulated heat were 80.92 and 45.64 J/g. For all samples, the mean maximum loss of mass rate was 9.26%. Analogously, for gaseous pollutants, the samples exhibited an exothermic reaction when the heating temperature exceeded 180 °C; the average maximum enthalpy was 0.395 mW, the average per gram of accumulated heat was 119.60 J/g, and the average maximum loss of mass rate was 4.79%. This slag/ash based zeolite has the advantages of low cost, high thermal stability, reusability, etc., and can be used as a new adsorbent material for indoor ventilation equipment.

2.
J Forensic Sci ; 58 Suppl 1: S227-34, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23067017

RESUMO

An inn fire occurring in the middle of the night usually causes a great deal more injuries and deaths. This article examines the case study of an inn fire accident that resulted in the most serious casualties in Taiwan's history. Data based on the official fire investigation report and NFPA921 regulations are used, and the fire scenes are reconstructed using the latest Fire Dynamics Simulator (FDS) program from NIST. The personnel evacuation time and time variants for various fire hazard factors of reconstructive analysis clarify the reason for such a high number of casualties. It reveals that the FDS program has come to play an essential role in fire investigation. The close comparison between simulation result and the actual fire scene also provides fire prevention engineers, a possible utilization of FDS to examine the effects of improved schemes for fire safety of buildings.

3.
J Forensic Sci ; 57(1): 246-9, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22040381

RESUMO

This study demonstrated the use of metallographic analysis and NIST's Fire Dynamics Simulator (FDS) program to identify the cause of an actual electrical fire. A severely carbonized steel plate and a cable with a bead were found inside a damaged switchboard from the debris of a factory fire. By metallographic analysis, the copper spatter on the steel plate was found to imply a short circuit has occurred and that this was the probable ignition source of the fire was supported by the presence of a small amount of copper oxide and by the cavities with the tree-like grain microstructures in the bead. The heat estimated to have been released per unit area of the switchboard in question (approximately 236.29 MJ/m(2)) served as key input data for applying the FDS simulation of the blaze. The simulation indicated that thermal insulation polyethylene (PE) played an important role in the rapid fire spread.

4.
J Forensic Sci ; 56(6): 1639-44, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21854381

RESUMO

The location of the hydroelectric power plant poses a high risk to occupants seeking to escape in a fire accident. Calculating the heat release rate of transformer oil as 11.5 MW/m(2), the fire at the Taiwan Dajia-River hydroelectric power plant was reconstructed using the fire dynamics simulator (FDS). The variations at the escape route of the fire hazard factors temperature, radiant heat, carbon monoxide, and oxygen were collected during the simulation to verify the causes of the serious casualties resulting from the fire. The simulated safe escape time when taking temperature changes into account is about 236 sec, 155 sec for radiant heat changes, 260 sec for carbon monoxide changes, and 235-248 sec for oxygen changes. These escape times are far less than the actual escape time of 302 sec. The simulation thus demonstrated the urgent need to improve escape options for people escaping a hydroelectric power plant fire.

5.
J Hazard Mater ; 171(1-3): 1145-9, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19619941

RESUMO

In the past, process incidents attributed to organic peroxides (OPs) that involved near misses, over-pressures, runaway reactions, and thermal explosions occurred because of poor training, human error, incorrect kinetic assumptions, insufficient change management, and inadequate chemical knowledge in the manufacturing process. Calorimetric applications were employed broadly to test organic peroxides on a small-scale because of their thermal hazards, such as exothermic behavior and self-accelerating decomposition in the laboratory. In essence, methyl ethyl ketone peroxide (MEKPO) is highly reactive and exothermically unstable. In recent years, it has undergone many thermal explosions and runaway reaction incidents in the manufacturing process. Differential scanning calorimetry (DSC), vent sizing package 2 (VSP2), and thermal activity monitor (TAM) were employed to analyze thermokinetic parameters and safety index. The intent of the analyses was to facilitate the use of various auto-alarm equipments to detect over-pressure, over-temperature, and hazardous materials leaks for a wide spectrum of operations. Results indicated that MEKPO decomposition is detected at low temperatures (30-40 degrees C), and the rate of decomposition was shown to exponentially increase with temperature and pressure. Determining time to maximum rate (TMR), self-accelerating decomposition temperature (SADT), maximum temperature (T(max)), exothermic onset temperature (T(0)), and heat of decomposition (DeltaH(d)) was essential for identifying early-stage runaway reactions effectively for industries.


Assuntos
Butanonas/química , Calorimetria/métodos , Explosões , Acidentes , Varredura Diferencial de Calorimetria/métodos , Química Orgânica/métodos , Substâncias Perigosas , Temperatura Alta , Peróxido de Hidrogênio/química , Cinética , Peróxidos/química , Pressão , Reprodutibilidade dos Testes , Taiwan , Temperatura , Termodinâmica
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