Search

Arson is a dangerous crime; even a small amount of an ignitable liquid can cause considerable losses in property and even human life. According to the National Fire Protection Association, [...], The identification of ignitable liquids is very important and challenging aspect in arson crime investigations. The detection of gasoline and diesel fuel components using solid phase micro-extraction prior to gas chromatography-mass spectrometry for the forensic analysis of fire debris has been carried out. Previous works show that the absorption characteristics of the substrate are one of the most important factors in determining the evaporation rate of the accelerants. In order to determine the presence of the fuel residues, four of the most common substrate materials were tested in this work; wool, cotton, silk and polyester. The obtained results indicate that both gasoline and diesel fuel accelerants persisted longer on wool and silk than on the other selected substrates. Such information illustrates the influence of fuel persistence times after extinguishing and the best materials to be scanned for ignitable liquids at the fire scene. Keywords: arson, gasoline, diesel, gas chromatography-mass spectrometry, solid phase micro-extraction, SPME

High-speed imaging combined with the optical access provided by a research engine offer the ability to directly image and compare ignition and combustion phenomena of various fuels. Such data provide valuable insight into the physical and chemical mechanisms important in each system. In this study, crank-angle resolved imaging data were used to investigate homogeneous charge compression ignition (HCCI) operation of a single-cylinder four-valve optical engine fueled using gasoline, indolene, and iso-octane. Lean operating limits were the focus of the study with the primary objective of identifying different modes of reaction front initiation and propagation for each fuel. HCCI combustion was initiated and maintained over a range of lean conditions for various fuels, from [phi] =0.69 to 0.27. The time-resolved imaging and pressure data show that high rates of heat release in HCCI combustion correlate temporally to simultaneous, intense volumetric blue emission. Lower rates of heat release are characteristic of spatially resolved blue emission. Gasoline supported leaner HCCI operation than indolene. Iso-octane showed a dramatic transition into misfire. Similar regions of preferential ignition were identified for each of the fuels considered using the imaging data. [DOI: 10.1115/1.2898720] Keywords: homogeneous charge compression ignition, imaging, optical engine

RNA-based stable isotope probing (RNA-SIP) technique is used to label and identify anaerobic benzene-degrading organisms from gasoline-contaminated aquifer. The results have revealed that the Azoarcus population is involved in the benzene degradation in the gasoline-contaminated groundwater under denitrifying conditions.

Methanol, ethanol and i-propanol are converted under methanol-to-gasoline (MTH)-like and conditions over zeolite H-ZSM-5. The total conversion capacity is more than 25 times higher for i-propanol when compared to the lower alcohols and the selectivity toward alkanes and aromatics has declined rapidly over time on stream when i-propanol is used as the reactant.

The phase separation that occurs with the addition of small volumes of water in ethanol-gasoline blends is a significant issue with this fuel that results in engine knock. A simple demonstration that illustrates this issue is presented.

Author Affiliations: Petrol created from carbon dioxide Burning petrol makes carbon dioxide that can be converted back to petrol hydrocarbons when it is treated with hydrogen and catalysts. But current [...], A catalytic process could help to mitigate greenhouse-gas emissions. A catalytic process could help to mitigate greenhouse-gas emissions.

An overall stoichiometric mixture of air, gaseous ammonia, and gasoline was metered into a single cylinder, variable compression ratio, supercharged cooperative fuel research (CFR) engine at varying ratios of gasoline to ammonia. The engine was operated such that the combustion was knock-free with minimal roughness for all loads ranging from idle up to a maximum load in the supercharge regime. For a given load, speed, and compression ratio, there was a range of ratios of gasoline to ammonia for which knock-free, smooth firing was obtained. This range was investigated at its rough limit and also at its maximum brake torque (MBT) knock limit. If too much ammonia was used, then the engine fired with an excessive roughness. If too much gasoline was used, then knock-free combustion could not be obtained while the maximum brake torque spark timing was maintained. Stoichiometric operation on gasoline alone is also presented, for comparison. It was found that a significant fraction of the gasoline used in spark ignition engines could be replaced with ammonia. Operation on about 100% gasoline was required at idle. However, a fuel mix comprising 70% ammonia/30% gasoline on an energy basis could be used at normally aspirated, wide open throttle. Even greater ammonia to gasoline ratios were permitted for supercharged operation. The use of ammonia with gasoline allowed knock-free operation with MBT spark timing at higher compression ratios and higher loads than could be obtained with the use of gasoline alone.