Extinction of Wood Fire: A Near-Limit Blue Flame Above Hot Smoldering Surface

Flat low-temperature two-stage flames were established on a Powling burner using rich diethyl-ether/ air or n-heptane/air mixtures, and nitrogen monoxide NO was added into the fuel-air mixtures with a concentration of 240 ppm. The temperature development and chemical-species histories, especially of NO, nitrogen dioxide NO2 and hydrogen cyanide HCN were examined associated with an emission-spectrum measurement from the low-temperature flames. Nitrogen monoxide was consumed in the cool-flame region, where NO was converted to the NO2. The NO2 generated, however, fell suddenly in the cool-flame degenerate region, in which the HCN superseded. In the blue-flame region the NO came out again and developed accompanied with remained HCN in the post blue-flame region. The NO seeding into the mixture intensified the blue-flame luminescence probably due to the cyanide increase.

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Association of polycyclic aromatic hydrocarbons in moss with blood biomarker among nearby residents in Portland, Oregon

10.1101/2021.07.15.21260592 ◽

2021 ◽

Author(s):

Igor Burstyn ◽

Geoffrey H. Donovan ◽

Yvonne L. Michael ◽

Sarah Jovan

Keyword(s):

Polycyclic Aromatic Hydrocarbons ◽

Air Quality ◽

Dna Adducts ◽

Aromatic Hydrocarbons ◽

Human Health Risk ◽

Monitoring Methods ◽

Wood Fire ◽

Individual Determinants ◽

Polycyclic Aromatic ◽

Environmental Air

Polycyclic aromatic hydrocarbons (PAHs) are a component of air pollutants that are costly to measure using traditional air-quality monitoring methods. We used an epiphytic bio-indicator (moss genus: Orthotrichum) to cost-effectively evaluate atmospheric deposition of PAHs in Portland, Oregon in May 2013. However, it is unclear if measurements derived from these bioindicators are good proxies for human exposure. To address this question, we simultaneously, measured PAH-DNA adducts in blood samples of non-smokers residing close to the sites of moss measurements. We accounted for individual determinants of PAH uptake that are not related to environmental air quality through questionnaires, e.g., wood fires, consumption of barbecued and fried meats. Correlation and linear regression (to control for confounders from the lifestyle factors) evaluated the associations. We did not observe evidence of an association between PAH levels in moss and PAH-DNA adducts in blood of nearby residents, but higher level of adduct were evident in those who used wood fire in their houses in the last 48 hours. It remains to be determined whether bio-indicators in moss can be used for human health risk assessment.

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An experimental study on the effects of swirling oxidizer flow and diameter of fuel nozzle on behaviour and light emittance of propane-oxygen non-premixed flame

Thermal Science ◽

10.2298/tsci140706210j ◽

2017 ◽

Vol 21 (3) ◽

pp. 1453-1462 ◽

Cited By ~ 1

Author(s):

Alireza Javareshkian ◽

Sadegh Tabejamaat ◽

Soroush Sarrafan-Sadeghi ◽

Mohammadreza Baigmohammadi

Keyword(s):

Reynolds Numbers ◽

Flame Length ◽

Nozzle Diameter ◽

Fuel Flow ◽

Maximum Value ◽

Fuel Nozzle ◽

Flame Shape ◽

The Stability ◽

Blue Flame

In this study, the stability and the light emittance of non-premixed propane-oxygen flames have been experimentally evaluated with respect to swirling oxidizer flow and variations in fuel nozzle diameter. Hence, three types of the vanes with the swirl angles of 30?, 45?, and 60? have been chosen for producing the desired swirling flows. The main aims of this study are to determine the flame behaviour, light emittance, and also considering the effect of variation in fuel nozzle diameter on combustion phenomena such as flame length, flame shape, and soot free length parameter. The investigation into the flame phenomenology was comprised of variations of the oxidizer and fuel flow velocities (respective Reynolds numbers) and the fuel nozzle diameter. The results showed that the swirl effect could change the flame luminosity and this way could reduce or increase the maximum value of the flame light emittance in the combustion zone. Therefore, investigation into the flame light emittance can give a good clue for studying the mixing quality of reactants, the flame phenomenology (blue flame or sooty flame, localized extinction), and the combustion intensity in non-premixed flames.

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A Blue Flame in the System N2O5/O3

Nature ◽

10.1038/135433c0 ◽

1935 ◽

Vol 135 (3411) ◽

pp. 433-433

Author(s):

T. M. LOWRY ◽

J. T. LEMON

Keyword(s):

Blue Flame

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A composition to render wood fire-proof

Journal of the Franklin Institute ◽

10.1016/s0016-0032(26)91595-0 ◽

1826 ◽

Vol 1 (3) ◽

pp. 187-188

Author(s):

Fuchs

Keyword(s):

Wood Fire

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Low-perchlorate blue-flame pyrotechnic compositions

Zeitschrift für Naturforschung B ◽

10.1515/znb-2021-0088 ◽

2021 ◽

Vol 76 (9) ◽

pp. 489-494

Author(s):

Dominykas Juknelevicius ◽

Rutger Webb ◽

Thomas M. Klapötke ◽

Arunas Ramanavicius

Keyword(s):

Ammonium Perchlorate ◽

Luminous Intensity ◽

Pyrotechnic Compositions ◽

Energetic Compositions ◽

Blue Flame

Abstract An ammonium perchlorate (AP) and copper(II) benzoate pyrotechnic blue-flame composition was gradually “diluted” by adding an experimental perchlorate-free blue-flame composition based on aminoguanidinium nitrate (AGN), malachite, PVC powder and shellac resin. Flame’s luminous intensity and specific luminous intensity were recorded and analyzed. A copper-aminoguanidinium (CuAG) complex was also synthesized and tested as an energetic additive in perchlorate-free blue-flame composition. Green-flame color was observed when testing chlorine-free energetic compositions with CuAG.

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